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  1. Jul 2018
    1. On 2017 Apr 12, Siegfried Hekimi commented:

      We obtained very different results that suggest that CLK-1 functions exclusively in ubiquinone biosynthesis and not in the nucleus to affect the mtUPR. In a paper entitled: A single biochemical activity underlies the pleiotropy of the aging-related protein CLK-1. By Liu et al. http://www.nature.com/articles/s41598-017-00754-z?WT.feed_name=subjects_energy-metabolism


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    1. On 2015 May 15, Kausik Datta commented:

      "P value of <0.1 was set as a meaningful difference with statistical significance."

      I am curious, how exactly was the acceptable P-value set at a non-traditional, less robust/discriminatory value? How was this considered 'meaningful', based on... which consideration(s)? Did the peer reviewers for this article raise this question to the authors, and if so, what was the authors' response?

      (Caveat: I don't have access to the full paper and, therefore, don't know if these questions have been answered in the discussion.)


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    1. On 2015 Sep 06, Lydia Maniatis commented:

      The claims of Blakeslee and McCourt are flawed on logical, methodological, theoretical, and empirical grounds.

      Perhaps the core error is the denial of perceptual facts, as described below (and as noted also by Gilchrist in his commentary on this article).

      In the Adelson checker-shadow illusion (to take one example), a check in apparent shadow looks white, while an equiluminant check, apparently in plain view, looks black. Aside from the additional presence of the apparent shadow, the experience of the two surfaces is similar to looking at a white check and at a black check under homogeneous illumination. Kohler (1935), describes a “real-world” version wherein a white and a black paper appear white and black, respectively, even if the illumination is adjusted so that the two surfaces are actually equiluminant.

      Imagine, now, what would happen if we asked a naive observer to report on “the intensity of the light coming from the surface of each of the two checks.” First, he or she would likely assume the question referred to the apparent illumination of the surfaces. In this case, the white, “shadowed” check should receive a lower rating than the black “plain-view” one. If we then tried to clarify that we want the observer to make matches based on “the amount of light each surface is sending to the eye,” (its luminance) I think the observer would have trouble a. understanding what we are asking and b. performing the required task. And I'm not sure anyone would be able to judge, with confidence, whether the two checks in the Adelson checkerboard are, or are not, in fact equiluminant. That's what makes the demo so impressive. Even if observers could estimate this value, the task would be difficult and the results unreliable. To achieve it, they would have to focus narrowly on each square, isolating it from the surround.

      Yet, Blakeslee and McCourt maintain that the latter task, which requires viewers to overide their spontaneous, salient perceptual experience, is “strictly based on appearance,” while the former, effortless experience is “based on an inferential judgment.” If, however, we define “appearance” as “what something looks like,” then the authors' arguments are obviously false, as can be confirmed by any observer.

      The authors' argue that the experience which is quite literally based on appearance, is actually a product of learning. This is a major claim (implying that learning can actually alter a percept from black to white), but the authors offer no evidence for it. All of the arguments and available evidence is against. As Gilchrist (2015) points out, even fish seem to naturally achieve this kind of learning. A child can see the Adelson checker-shadow effect as effortlessly as an adult. Our perceptions aren't affected by what we learn about the nature of light and the properties of surfaces, we don't have to learn how to judge when a surface is in shadow or merely darker than its neighbor, or when it is covered by various types of transparency, we don't even have to learn that at night things don't actually change color. Given the difficulty scientists have in analyzing and modelling percieved lightness, and given that massive, early exposure to artificial images mimicking illumination variation has no discernible effect on our perception of the “real” world, the claim that people go through a process of learning to make the inferences necessary to achieve veridical percepts in natural conditions does not seem credible. B and M have certainly not tested it.

      The quality that the authors argue is “strictly based on appearance” is a quality that they term “brightness,” defined as the perceptual correlate of luminance. The view that there is a perceptual correlate of luminance seems to be uncontroversial among lightness researchers (e.g. Kingdom, 2011; Gilchrist, 1999)), although Anderson (2014) seems to define brightness (more properly, in my opinion) as apparent illumination. The claim seems easy to refute.

      Suppose we observe a set of surfaces lacking cues to differential illumination, and that some appear white, some gray, some black. Suppose, then, that we observe the same set of surfaces, at a different time, under a different degree of illumination. Assume that have completely forgotten the previous experience with the surfaces, and are again asked to judge their white/gray/black character. Our responses will typically be similar to those we gave in the first (now forgotten) instance. In other words, even though the illumination (and consequently the luminance) of the surfaces will have changed, our responses will remain the same. If the range of luminances is complete enough, they will, in both cases, be correlated with reflectance and not with luminance. Thus, even under homogeneous illumination, we cannot say that we are perceiving luminance, or that perception is more direct than in other situations. As always, the percept is the product of a complex visual process based on luminance values and structural assumptions.

      When it comes to the case of non-homogenous (apparent) illumination, the authors seem to be treating illumination boundaries as though they were directly-perceived facts serving to support “inferentially” perceived lightness judgments. They say, for example, that “when the illumination component is clearly visible” the observer can use “brightness contrast” at the boundary to infer the magnitude of the illumination. There are a number of problems with this description.

      First, if a shadow is perceived – is “clearly visible” - as the cause of the luminance boundary, then viewers are perceiving a double-layer – a surface with lightness x and an apparent shadow of darkness y lying on top of it. They are not perceiving a single “brightness” value. The authors are using the term “brightness” when they actually mean luminance.

      Relatedly, the illumination boundary only becomes “clearly visible” after the visual process has inferred its presence based on the luminance structure – including the relative luminances at luminance boundaries - of the image. Whether the darker side of an edge will be perceived as being similar in reflectance, but lower in illumination than its neighbor, or as darker than its neighbor due to a lower reflectance, or any other combination of possibilities, depends on the global structure of the image. Given certain conditions, even a non-existent luminance edge may produce an apparent lightness difference, as in the case of illusory surfaces. So the argument that perceiving a surface as continuing beneath a “shadow” boundary is more inferential than perceiving a particular surface as gray due to its luminance relative to other surfaces in an image is naive. If “appearance-based” means “based on luminances”, then all perception is appearance-based. If it means that surfaces are perceived based on local luminance conditions, then it never is. Local conditions do not even determine photoreceptor activity in the horseshoe crab.

      As corroborating evidence, the authors point to a few references, including Blakeslee and McCourt (2008), which is supposed to prove the existence of “brightness” judgments. Their stimuli consist of the classic simultaneous contrast demo plus variations that create weak impressions of differential illumination. The “brightness” judgments are defined as those that arise when observers are instructed to focus narrowly on the targets. This is similar to applying a mask. Effectively, we are talking about the same visual process acting on a different stimulus, not about a different type of judgment. Due to the weakness of the structural cues to differential illumination in B and M's (2008) stimuli, the ability of observers to isolate the target in this way is very easy. The demand would be much more difficult, and the results surely very different, if the stimulus had been the Adelson checkerboard.


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    1. On 2014 Nov 25, Harri Hemila commented:

      A secondary analysis of this study has been published in Hemilä H, 2013, DOI. The secondary analysis calculated that when the participants suffered from the common cold, vitamin C increased histamine PC20 level by 3.2 fold (95% CI 2.0 to 5.1). After the participants had recovered, the effect of vitamin C was smaller so that there was a significant interaction between vitamin C effect on PC20 and the presence of the common cold (P = 0.003).


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    1. On 2016 Oct 11, UFRJ Neurobiology and Reproducibility Journal Club commented:

      In this article, the authors demonstrate that the response to an aversively conditioned context is different between rats that have undergone conditioning individually or collectively, and suggest that this is mediated by olfaction.

      Despite the interesting findings, we would like to point out that the statistical methods used for the results shown in Figures 2E and 4C do not support the conclusions made by the authors. In Figure 1B, the illustrated result was that the collectively conditioned group presented a significant decrease (p<0.01) in fear response 24 h after training when compared to animals conditioned individually. The same kind of comparison (collective vs. individual conditioning) was performed in Figure 2E, with the test performed 3.5 h after training; in this case, no statistical significance (p> 0.1) was found (even though a trend towards reduced freezing in the collectively conditioned group can be observed in the figure). Based on this, the authors conclude that “these data argue strongly that fear acquisition was similar in both groups and that neuronal mechanisms mediating fear memory consolidation and/or expression are involved in the markedly attenuated fear memory in Group animals.”

      This conclusion, however, is based on a common statistical misconception: namely, to infer that, if a significant difference at a given threshold is found between two groups in one condition (i.e. collective conditioning) but not in another (i.e. individual condition), this implies that there is a significant difference between the two conditions. This statistical reasoning is erroneous, since the differences found in both conditions can be similar in magnitude (as they seem to be in this case), and the fact that one but not the other is found to be significant at an arbitrary significance threshold can be a consequence of statistical power, variability, or mere chance. As discussed by (Nieuwenhuis S, 2011) to argue in favor of a difference in magnitude between two differences found in individual comparisons, the correct statistical approach would be to test whether there is a significant interaction between the two independent variables (in this case, group and time of testing), and not simply report that an effect was statistically significant while the other it was not.

      The same error occurs in Figure 4C, in which the collectively conditioned sham group presented a significant reduction compared to individually conditioned sham rats (p < 0.05) individually, while this difference between types of conditioning was not found (p > 0.1) in anosmic rats. Although the difference in this case indeed seems larger in the sham group, results for the interaction between type of conditioning and anosmia were not shown, and the post-hoc results presented cannot be used to conclude that the sense of smell is responsible for the difference between individual and collective conditioning. This does not mean that the sense of smell does not play a role, but to support this conclusion the authors should present a statistical analysis that actually tests this hypothesis.


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    1. On 2015 Jun 06, A Martinez-Arias commented:

      This manuscript claims the discovery of a new kind of Embryonic Stem (ES) cell, so called ‘region specific Epiblast stem cells (rsEpiSC). A close look at the protocols, genetics and cell behaviours indicates that what is reported is likely to be an improved method for the maintenance of EpiSCs and the closely related human ES cells; it would be misleading to describe a more stable population as a new entity.

      The main finding reported here is that inhibition of Wnt signalling in cultures of EpiSCs, and also human ES cells, leads to a stable pluripotent population. As briefly indicated below, this has been reported a number of times before, as has the ability of EpiSCs to integrate in postimplantation embryos, the other finding presented here as new. The observation that stabilized human ES cells can undergo a similar integration is, however, novel, though the degree to which this happens and its value will await further experiments.

      It is well known that ES and EpiS cells are, for the most part, heterogeneous populations in dynamic equilibria. In the case of ES cells this can be biased towards a stable state, called ‘ground state’, by application of two inhibitors, one for MEK and another for GSK3 [1]. It is also well known that in contrast with ES cells, when EpiSCs and human ES cells are presented with high levels of Wnt signalling they differentiate [2, 3] and over the last few years a number of reports have shown that inhibition of Wnt secretion or Wnt/ß-catenin signalling increases the self renewal of EpiSCs populations [4-6]. Thus a cocktail of Activin, FGF2 together with Wnt/ß-catenin inhibitors leads to efficient derivation of EpiSCs as well as their stable culture. This is confirmed in this report without acknowledging the earlier studies –interestingly some of these studies are referred to but only as discussing Wnt signalling in pluripotency. Having repeated this observation, the authors now notice that removal of Activin from the cocktail –but not inhibition of Activin signalling, which is not tested- improved the stability of the culture; this tweak is novel and mechanistically intriguing, though it is not pursued further. Thus the main message of the work is that EpiSCs grown or derived in the presence of FGF2 and Wnt inhibitors are stable (this is no new kind of ES cell).

      With regard to the ability of the cells to integrate in the posterior part of postimplantation embryos, there are also precedents showing that EpiSCs, which indeed are not able to integrate in preimplantation embryos under normal conditions, can and will integrate in postimplantation embryos [7, 8]. The point made here that ‘stable EpiSCs integrate preferentially in posterior regions of the embryo is not surprising as integration is likely to be easier in the region undergoing gastrulation, which is ongoing in the posterior region at the time of the injection. Furthermore, the conclusion that ‘rsEpiSCs’ are related to the posterior proximal epiblast of stage E6.5 is similar to that obtained by Kojima et al. that although it is possible to obtain EpiSCs from a range of stages during gastrulation, EpiSC lines tend to correspond to anterior primitive streak i.e. posterior proximal E6.5 [8]. The results presented here are compatible with the observation that EpiSCs derived from embryos at different stages of gastrulation can be different [8] i.e there might be many rsEpiSCs, which is probably not a helpful notion.

      One of the arguments used by the authors to claim the identification of a new type of stem cell is their transcriptional profile. However, EpiSC lines derived from different stages around gastrulation have different properties and transcriptional profiled and much of these differences are likely to be down to signalling [8]. Thus it is not that surprising that a population of EpiSCs severely deprived of Wnt and Activin signalling exhibits a special transcriptional profile and maps, in a PCA plot, away from other cells in different states and notably from EpiSCs grown in Activin and FGF2, a very different cocktail. It is likely that under appropriate experimental conditions, rsEpiSCs will be shown to correspond to one of the EpiSCs derived by Kojima et al. [8], though the changes and adaptations associated with growth in specific signalling environments would make the comparison challenging.

      In summary, this report is a protocol to obtain a state which is to EpiSCs what the ground state (2i) is to the ES cells. This is certainly useful but not enough to talk about a new kind of ES cells. Of course, this is an opinion. Nevertheless, the work provides further support to the importance of Wnt signalling in the control of the dynamics of stem cell populations.

      References [1] Ying QL, Wray J, Nichols J, Batlle-Morera L, Doble B, Woodgett J, et al. The ground state of embryonic stem cell self-renewal. Nature 2008;453:519-23. [2] Singh AM, Reynolds D, Cliff T, Ohtsuka S, Mattheyses AL, Sun Y, et al. Signaling network crosstalk in human pluripotent cells: a Smad2/3-regulated switch that controls the balance between self-renewal and differentiation. Cell Stem Cell 2012;10:312-26. [3] Davidson KC, Adams AM, Goodson JM, McDonald CE, Potter JC, Berndt JD, et al. Wnt/beta-catenin signaling promotes differentiation, not self-renewal, of human embryonic stem cells and is repressed by Oct4. Proc Natl Acad Sci U S A 2012;109:4485-90. [4] Kurek D, Neagu A, Tastemel M, Tuysuz N, Lehmann J, van de Werken HJ, et al. Endogenous WNT signals mediate BMP-induced and spontaneous differentiation of epiblast stem cells and human embryonic stem cells. Stem cell reports 2015;4:114-28. [5] Kim H, Wu J, Ye S, Tai CI, Zhou X, Yan H, et al. Modulation of beta-catenin function maintains mouse epiblast stem cell and human embryonic stem cell self-renewal. Nat Commun 2013;4:2403. [6] Sumi T, Oki S, Kitajima K, Meno C. Epiblast ground state is controlled by canonical Wnt/beta-catenin signaling in the postimplantation mouse embryo and epiblast stem cells. PLoS One 2013;8:e63378. [7] Huang Y, Osorno R, Tsakiridis A, Wilson V. In Vivo differentiation potential of epiblast stem cells revealed by chimeric embryo formation. Cell Rep 2012;2:1571-8. [8] Kojima Y, Kaufman-Francis K, Studdert JB, Steiner KA, Power MD, Loebel DA, et al. The transcriptional and functional properties of mouse epiblast stem cells resemble the anterior primitive streak. Cell Stem Cell 2014;14:107-20.


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    1. On 2015 Jun 30, Prashant Sharma, MD, DM commented:

      This paper basically addresses a cost-cutting issue that sometimes unfortunately still surfaces in resource-poor settings, wherein electrophoresis-derived hemoglobin fraction percentages are used for clinical decision making.

      While electrophoresis followed by elution and chemical or photometric measurement is acceptable, electrophoresis followed by densitometry, we found, is simply too unreliable to be used in tests that establish genetic diagnoses or are used to screen antenatal women for fetal diseases.

      We, the authors, would be happy to discuss the findings and our experiences with interested readers at the email provided at the publisher website.


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    1. On 2016 Dec 18, Zvi Herzig commented:

      The concerns for potential chronic toxicity in 2 of the 42 tested products refer to (1) terpene hydrocarbons in relation to Maximized Survey-Derived Intake (MSDI) levels and (2) diacetyl in relation to NIOSH-recommended safety limits.

      MSDIs are the normal exposures considered when food safety standards are established. Exceeding them isn't necessarily hazardous, but it implies a level not considered in the assessment. Therefore, it's important to consider other available safety limits when possible.

      The strictest 8 hr occupational exposure limit for terpenes is 20 ppm (111 mg/m3) Granström KM, 2010. Occupational safety limits consider a ~10 m3/workday respiration rate for active workers Kuempel ED, 2015. This corresponds to a safe terpenes inhalation limit of 1,110 mg/workday.

      The highest concentration of terpenes in this study is 106.7 mg/g. A mean consumption of 3 g e-liquid daily among EC users is noted. This corresponds to terpene consumption of 320.1 mg/day for the highest terpene concentration e-liquid -- a fraction of the aforementioned safety limit.

      Furthermore, with a high prevalence of switching between flavors Farsalinos KE, 2013, these quantities are further diluted in relation to chronic use. This study detected hydrocarbons at 2.5 mg/g on average, all hydrocarbons being terpenes. In contrast, a single cigarette delivers 4.9 mg of hydrocarbons, including 1.1 mg of terpenes Perfett TA, 2014. Despite the much higher exposure to terpenes in cigarette smoking, terpenes are not noted in any of the lists of cigarette smoke's notable toxicants.

      With regards diacetyl estimated to result in 126 µg/day exposure in one case, it should be noted that tobacco smokers inhale 5700 µg diacetyl per day Farsalinos KE, 2015, 45 times greater than the exposure resulting from using the product with the highest diacetyl level among 42 liquids tested in this study.


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    1. On 2016 Apr 05, Marko Premzl commented:

      The third party data gene data sets of eutherian adenohypophysis cystine-knot genes (128 complete coding sequences) and D-dopachrome tautomerase and macrophage migration inhibitory factor genes (30 complete coding sequences) HF564658-HF564815 were deposited in European Nucleotide Archive under research project "Comparative genomic analysis of eutherian genes" (https://www.ebi.ac.uk/ena/data/view/HF564658-HF564815). The 158 complete coding sequences were curated using tests of reliability of eutherian public genomic sequences included in eutherian comparative genomic analysis protocol including gene annotations, phylogenetic analysis and protein molecular evolution analysis (RRID:SCR_014401).

      Project leader: Marko Premzl PhD, ANU Alumni, 4 Kninski trg Sq., Zagreb, Croatia

      E-mail address: Marko.Premzl@alumni.anu.edu.au

      Internet: https://www.ncbi.nlm.nih.gov/myncbi/mpremzl/cv/130205/


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    1. On 2017 Mar 19, NLM Trainees’ Data Science Journal Club commented:

      The NLM Trainees Data Science Journal Club for this discussion consisted of several NLM staff members, including one of the paper’s authors. In brief, the authors employed a visual and a computational method to explore the contribution of individual drugs to a drug class-level signal in the context of adverse events. The authors used both techniques to identify class effects caused by all members of a drug class individually, as well as class effects based on a subset of drug class members.

      As background information regarding adverse events, one group member pointed out that there has to be enough evidence between a drug or class and an adverse event for it to be formally labeled an adverse event. As such, the type of comparison performed in this study has the potential to introduce false positives, where there is a co-occurrence between a drug and an event that is not to the level of a “label-able” event.

      In terms of methodology, the group discussed that, while this study is biased towards using case reports, the strength of evidence would likely be higher if based on randomized controlled trials; however, RCT’s are generally more focused on drug efficacy than safety.

      The question was raised as to whether study results might differ if the drugs or adverse events were mapped using different terminologies than ATC and MeSH, respectively. In response, the author pointed out that the FDA uses MEDRA to report events, but for the purposes of this study, it was more complicated to use than MeSH, as it would have required hand curation (beyond the automated curation the UMLS offers) to be useable. That said, the general methodology used by the authors is largely terminology agnostic and can be used with any terminology that is reasonably hierarchical.

      One group member was curious whether this process could be used for clinical decision support. Discussion revealed that this methodology is not suited for CDS, as the evidence would need to be clearer. For CDS use, the process would need to be based on drug labels or drug information systems, which are usually expressed at the individual drug level. It might be interesting to know if a class was affecting adverse events at the class level or based on a subset of the class, but this would not be the primary concern in a primary care setting. However, the results of the study could be valuable to drug safety professionals and those building adverse event repositories to support their review or decisions in regard to adverse event relationships.


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    1. On 2016 Aug 01, Joaquim Radua commented:

      Re: the first comment, I think there may be some unfortunate confusion. Raw p-values of current voxelwise meta-analyses have not the same meaning as usual p-values because they are not derived from the usual null hypothesis (“there are no differences between groups”), but from another null hypothesis (“all voxels show the same difference between groups”). Thus, up to the moment one of the only ways to "approximately" know if the results of a voxelwise meta-analysis are neither too liberal nor too conservative is to compare them with the results of a mega-analysis of the same data, and that's what it was done.


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    2. On 2016 Jul 14, Lars Schulze commented:

      Dear Christopher Tench,

      we agree that it is important to control the rate of false positives in meta-analyses. Please note, that our study did apply empirically validated thresholding procedures that have been shown to not only balance sensitivity and specificity, but also to be equivalent to a corrected P-value of 0.05 (Radua et al., 2012). To even further reduce the possibility of false positive results, we used an additional voxel-wise threshold with Z-values >1.

      Thus, our meta-analysis applied validated and recommended methods to control the inflation of false positive results.

      Sincerely, Lars Schulze


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    3. On 2016 Jun 19, Christopher Tench commented:

      The methods employed do not constitute a meta analysis as uncorrected p-values offer no protection against false positive results. Consequently the study provides no evidence of significant consistency across studies. Uncorrected p-values are not useful in meta analysis of neuroimaging studies.


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    1. On 2017 Jul 21, Horacio Rivera commented:

      Are citations related to a faulty writing style or simply to content? The results got by Weinberger et al. (2015) in their analysis of >1,000,000 abstracts may not be so surprising. Taking into account the pervasiveness of an improper writing style (Woodford FP, ed. Scientific Writing for Graduate Students, CBE 1986; Gopen&Swan, Am Sci 1990, 78: 550; Knight J, Nature 2003, 423: 376; Editorial, Nat Struct Mol Biol 2010, 17: 139), I guess that the decreased citation rate associated with half of 15 well-known stylistic features can equally be ascribed to the papers’ content. Actually, the opposite pattern found for the remaining features suggests that style alone is not a consistent predictor of citation rates. A more reliable study would compare a sample of "well written" vs "poorly written" abstracts, classified according to conventional wisdom by expert colleagues, instead of analyzing all available abstracts in a given period. I do two additional comments: 1. Rule 4 of the authors "Use the present tense" is unsuitable when dealing only with abstracts. At least in biomedicine, the general advice is to use the past tense in the "M&M" and "Results" sections that account for half or more of an abstract. Obviously, the results would have been the opposite ones if the rule "Use the past tense" had been applied. 2. The assertion that in "writing a paper, the limiting step is the ability to find the right article" appears nonsense inasmuch it disregards the crucial intellectual input required for successful writing. In other words, "to find the right article" is a preparatory rather than limiting step. To conclude, I praise the effort of Weinberger et al. (2015) in summarizing ten simple rules aimed to improve our writing style.


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    1. On 2015 May 17, Egon Willighagen commented:

      Like Open Access, "sharing" is a meaningless term if it is not linked to meaningful rights. The problems outlined in this paper result from the fact that their may be a wish to share data but only if it allows you to take back the data. Private, custom data licenses do just that. There is nothing wrong with this kind of sharing, but it must not be confused with Open Data. It must not be confounded with terms like "publicly available", because if it needs a signature, it's not publicly available. That makes the lead of this article quite misleading.

      For public or open data, three basic rights are part of the social agreement between the data owner (yes, fact in many countries; database rights, etc) and data user. These rights are: 1. make a copy, 2. make modifications, and 3. reshare (under the same conditions). By using a license (or waiver) that gives this rights automatically to the receiver, then there is no need for signatures. It also allows for anyone to make the mappings that are required to convert one format into another.


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    1. On 2016 Aug 23, Ben Goldacre commented:

      This trial has the wrong trial registry ID associated with it on PubMed: both in the XML on PubMed, and in the originating journal article. The ID given is NCT0033633. We believe the correct ID, which we have found by hand searching, is NCT00336336.

      This comment is being posted as part of the OpenTrials.net project<sup>[1]</sup> , an open database threading together all publicly accessible documents and data on each trial, globally. In the course of creating the database, and matching documents and data sources about trials from different locations, we have identified various anomalies in datasets such as PubMed, and in published papers. Alongside documenting the prevalence of problems, we are also attempting to correct these errors and anomalies wherever possible, by feeding back to the originators. We have corrected this data in the OpenTrials.net database; we hope that this trial’s text and metadata can also be corrected at source, in PubMed and in the accompanying paper.

      Many thanks,

      Jessica Fleminger, Ben Goldacre*

      [1] Goldacre, B., Gray, J., 2016. OpenTrials: towards a collaborative open database of all available information on all clinical trials. Trials 17. doi:10.1186/s13063-016-1290-8 PMID: 27056367

      * Dr Ben Goldacre BA MA MSc MBBS MRCPsych<br> Senior Clinical Research Fellow<br> ben.goldacre@phc.ox.ac.uk<br> www.ebmDataLab.net<br> Centre for Evidence Based Medicine<br> Department of Primary Care Health Sciences<br> University of Oxford<br> Radcliffe Observatory Quarter<br> Woodstock Road<br> Oxford OX2 6GG


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    1. On 2015 May 01, David Mage commented:

      "Close, but no cigar!" Human 5HT2A is autosomal. OMIM shows 182135 - 5-@HYDROXYTRYPTAMINE RECEPTOR 2A; HTR2A Cytogenetic locations: 13q14.2; SIDS and all respiratory deaths under 5 years of age have a 50% male excess suggesting an unidentified X-linked gene with a recessive non-protective allele with frequency q = 2/3 in Hardy-Weinberg Equilibrium may be involved (NB: 5HT2C is X-linked). See Mage DT, Donner EM. An explanation for the 25% male excess mortality for all children under 5. Scandinavian Journal of Forensic Science 2015;21(1) doi: 10.1515/sjfs-2015-0001


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    1. On 2016 Aug 23, Ben Goldacre commented:

      This trial has the wrong trial registry ID associated with it on PubMed: both in the XML on PubMed, and in the originating journal article. The ID given is NCT0102455. We believe the correct ID, which we have found by hand searching, is NCT01024595.

      This comment is being posted as part of the OpenTrials.net project<sup>[1]</sup> , an open database threading together all publicly accessible documents and data on each trial, globally. In the course of creating the database, and matching documents and data sources about trials from different locations, we have identified various anomalies in datasets such as PubMed, and in published papers. Alongside documenting the prevalence of problems, we are also attempting to correct these errors and anomalies wherever possible, by feeding back to the originators. We have corrected this data in the OpenTrials.net database; we hope that this trial’s text and metadata can also be corrected at source, in PubMed and in the accompanying paper.

      Many thanks,

      Jessica Fleminger, Ben Goldacre*

      [1] Goldacre, B., Gray, J., 2016. OpenTrials: towards a collaborative open database of all available information on all clinical trials. Trials 17. doi:10.1186/s13063-016-1290-8 PMID: 27056367

      * Dr Ben Goldacre BA MA MSc MBBS MRCPsych<br> Senior Clinical Research Fellow<br> ben.goldacre@phc.ox.ac.uk<br> www.ebmDataLab.net<br> Centre for Evidence Based Medicine<br> Department of Primary Care Health Sciences<br> University of Oxford<br> Radcliffe Observatory Quarter<br> Woodstock Road<br> Oxford OX2 6GG


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    1. On 2017 May 29, Rashmi Das commented:

      We thank Harri for his comment. It is really sad to see that Harri is trying to disseminate his personal opinion (HANDLE) THOUGH A DETAILED PEER-REVIEWED REPORT IS AVAILABLE AT COCHRANE LIBRARY. We need to share the sequence of events here, so that, things can become more transparent. After our publication of the Cochrane review in 2011, Harri published another review on the same topic in Open Respiratory Medicine Journal in same year. He provided comment on our 2011 Cochrane review in 2012, which we incorporated in 2013 version of the Cochrane review. In 2015, Harri made a report on the Cochrane review 2013 version (not 2011 version, which is still available there) and complained to the Cochrane Editor (Whatever has been mentioned in the ABOVE HANDLE: http://hdl.handle.net/10138/153180, which is a PERSONAL OPINION AND NOT A PEER-REVIEWED CONTENT). The Cochrane editors made a detailed inquiry (INVOLVED AN INDEPENDENT STATISTICIAN) and made the recommendation to withdraw the review NOT BASED ON TEXT PLAGIARISM BUT BASED ON INCONCLUSIVE DATA ANALYSIS (Detail available at: http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD001364.pub5/abstract;jsessionid=FCA801377C71E663B0004B9BBB92A908.f02t03). This report also mentions that we have acknowledged and cited his review (Hemilla 2011). But the irony is that the ABOVE HANDLE (Which contains DIRECT COPY OF THREE IMAGES/FIGURES FROM OUR PUBLICATION) IS BEING DISSEMINATED AS A PUBLICATION/REFERENCE TO SENT THE MESSAGE THAT WHAT HE HAS MENTIONED IS ENTIRELY RIGHT (BUT THE COCHRANE REPORT DOES NOT FULLY AGREE TO THIS). MOREOVER THE HANDLE IS STILL ACTIVE AFTER THE COCHRANE LIBRARY PUBLISHED THE REPORT AND REACHED THE CONCLUSION.


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    1. On 2015 Jul 14, Andrew Kewley commented:

      The authors show that questionnaires and other diagnostic methods lead to statistical overlap (mush) and therefore conclude that this group of disorders can be re-branded as a spectrum called "ALPIM".

      The sample group of this study is highly biased and cannot be generalised, so the question is, should this study be replicated with a community/population based study?

      But in the big picture, what is there to gain from this?

      Medicine demands specific criteria so that medical or psycho-social interventions can be targeted to those whom will benefit.

      Yes, diagnostic measure and criteria for the underlying illnesses needs to become more specific to become more useful. But ALPIM does not offer specificity of diagnosis, nor specific treatments, therefore I don't really see this as a worthwhile direction.


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    1. On 2015 May 28, Peter Good commented:

      Cochran et al. measured brain glutamate, glutamine, GABA, and other metabolites by MRS in the anterior cingulate cortex of ASD adolescents to test whether autistic behavior arises from imbalance of excitatory vs. inhibitory neurotransmitters. They found normal concentrations of excitatory transmitter glutamate, but significantly high non-transmitter glutamine and significantly low inhibitory GABA. They concluded high brain glutamine and/or low GABA might explain imbalance of excitatory vs. inhibitory transmission – i.e. autistic behavior.

      True, low brain GABA could be responsible – but implicating high brain glutamine in autistic behavior is risky at best, and potentially dangerous. Not only do ASD children consistently have low plasma glutamine, high brain glutamine appears to protect against ASD. This is most obvious in children with high brain glutamine from inborn urea cycle disorders (UCD) or propionic acidemia (PA) [Good 2014]. In UCD, failure of the liver urea cycle to detoxify blood ammonia at first pass allows high levels into the brain, which astrocytes detoxify by combining with glutamate to form glutamine. Krivitzky et al.: “Children in this cohort [UCD] show other behavioral/emotional strengths, including a minimal percentage with previous diagnoses of Autism spectrum disorders, mood disorders, and other psychiatric disorders.”[Krivitzky L, 2009] Saul Brusilow (MD) never mentioned autism or autistic behavior in any paper on UCD or hepatic encephalopathy (HE) [personal communication 2013]. Gropman et al., however, noted patients with partial deficiencies of urea cycle enzymes and late-onset presentations may show signs of autism [Gropman AL, 2007]. Cochran et al. also found the osmolyte myoinositol normal in ASD brains; when astrocyte glutamine is high in urea cycle disorders or HE, myoinositol is consistently low. Gabis et al., however, found myoinositol high in ASD astrocytes [Gabis L, 2008].

      Propionic acidemia is another inborn metabolic disorder where high blood ammonia becomes high brain glutamine. Al Owain et al.: “In the consensus conference about diagnosis and management of PA hosted in Washington, D.C. in January 2011, there was no reported association among the neurological sequelae of the disease between PA and autism.”[Al-Owain M, 2013] Other physicians who treat PA and UCD children also report they rarely show autistic behavior. Sabine Scholl-Bürgi (MD): “In our PA patient group none has an ASD.”[personal communication 2014]. Professor of pediatrics (MD): “I see lots of kids with PA and UCD but few (perhaps none) have ASD.”[personal communication 2013]

      Moreover, plasma concentrations of glutamine and GABA in ASD children are consistently opposite brain concentrations detected by Cochran et al. Plasma glutamine is consistently low [e.g. Moreno-Fuenmayor H, 1996; Aldred S, 2003; Shimmura C, 2011] and plasma GABA high [Cohen 2000; Dhossche D, 2002]. Ghanizadeh concluded: “The low level of plasma glutamine . . . is suggested as a screening test for detecting autism in children especially those with normal IQ. The decreased level has been reported before in all children with autism.”[Ghanizadeh A, 2013] Dhossche et al. thought high plasma GABA explained mood disorders and stupor. Burrus concluded a reaction between ammonia and propionic acid could produce a molecule structurally very similar to GABA [Burrus CJ, 2012].

      Glutamine is normally the most abundant amino acid in blood [Souba WW, 1991], a primary brain osmolyte, alternative fuel for brain neurons and astrocytes (especially during hypoglycemia) [Stelmashook EV, 2011], and primary fuel in rapidly replicating cells (e.g. blood vessel endothelial cells, intestinal enterocytes, liver cells, and lymphocytes) [Souba WW, 1987; Souba WW, 1991; Deutz NE, 2008]. Glutamine released from skeletal muscles for anabolic responses to infection may explain the dramatic ability of fever to relieve autistic behavior [Good P, 2013]. A new clue to this phenomenon was recently published at <www.autismstudies.net>.

      Autism Research Institute practitioners commonly give ASD patients oral glutamine to heal their intestines, from 250mg–8g/day, with few side effects (some hyperactivity) [Good P, 2013] – although one neurologist reported seizures. Only two practitioners, however, reported improved behavior from glutamine. Franco Verzella (MD) in Bologna, Italy gives ASD children 5–7g/day of oral glutamine after cleansing their intestines of pathogens like bacteria and Candida: “Multifactorial and multisystemic is the condition, so that the improvement has different aspects in different children. Most common: sedation, less stereotypes, better sleep, more concentration.”[personal communication 2013]

      Cochran and colleagues need to think twice about reducing brain glutamine in ASD children – whose plasma and brain glutamine are more likely TOO LOW than too high. Pangborn (2013) recommended the free amino acid taurine as a natural way to increase conversion of ammonia + glutamate to glutamine.

      Peter Good Autism Studies La Pine OR www.autismstudies.net autismstudies1@gmail.com

      Aldred S, Moore KM, Fitzgerald M, Waring RH. Plasma amino acid levels in children with autism and their families. J Autism Dev Disord 2003;33:93–97.

      Al-Owain M, Kaya N, Al-Shamrani H, et al. Autism spectrum disorder in a child with propionic acidemia. JIMD Rep 2013;7:63–66.

      Burrus CJ. A biochemical rationale for the interaction between gastrointestinal yeast and autism. Med Hypotheses 2012;79:784–785.

      Cohen BI. Infantile autism and the liver: a possible connection. Autism 2000;4:441–442.

      Deutz NEP. The 2007 ESPEN Sir David Cuthbertson Lecture: amino acids between and within organs. The glutamate-glutamine-citrulline-arginine pathway. Clin Nutr 2008;27(3):321–327.

      Dhossche D, Applegate H, Abraham A, et al. Elevated plasma gamma-aminobutyric acid (GABA) levels in autistic youngsters: stimulus for a GABA hypothesis of autism. Med Sci Monit 2002;8:PR1–PR6.

      Gabis L, Wei Huang, Azizian A, et al. 1H-magnetic resonance spectroscopy markers of cognitive and language ability in clinical subtypes of autism spectrum disorders. J Child Neurol 2008;23(7):766–774.

      Ghanizadeh A. Increased glutamate and homocysteine and decreased glutamine levels in autism: a review and strategies for future studies of amino acids in autism. Dis Markers 2013;35:281–286.

      Good P. Does infectious fever relieve autistic behavior by releasing glutamine from skeletal muscles as provisional fuel? Med Hypotheses 2013;80:1–12.

      Good P. Why do children with propionic acidemia or urea cycle disorders rarely show autistic behavior? Autism–Open Access 2014;4:3.

      Gropman AL, Summar M, Leonard JV. Neurological implications of urea cycle disorders. J Inherit Metab Dis 2007;30:865–879.

      Krivitzky L, Babikian T, Lee HS, et al. Intellectual, adaptive, and behavioral functioning in children with urea cycle disorders. Pediatr Res 2009;66:96–101.

      Moreno-Fuenmayor H, Borjas L, Arrieta A, et al. Plasma excitatory amino acids in autism. Invest Clin 1996;37:113–128.

      Pangborn JB. Nutritional Supplement Use for Autism Spectrum Disorder. San Diego: Autism Research Institute; 2013.

      Shimmura C, Suda S, Tsuchiya KJ, et al. Alteration of plasma glutamate and glutamine levels in children with high functioning autism. PLoS One 2011;6:e25340–e25346.

      Souba WW. Interorgan ammonia metabolism in health and disease: a surgeon’s view. J Parenter Enteral Nutr 1987;11:569–579.

      Souba WW. Glutamine: a key substrate for the splanchnic bed. Ann Rev Nutr 1991;11:285–308.

      Stelmashook EV, Isaev NK, Lozier ER, et al. Role of glutamine in neuronal survival and death during brain ischemia and hypoglycemia. Int J Neurosci 2011;121:415–422.


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    1. On 2016 Feb 16, Rafa Carretero commented:

      Why should I publish? I wonder that question again and again, and to be honest, I don't have any suitable answer yet. It's been a long time since I decided to make a PhD and to begin to publish scientific papers. I don't know if it's worth it. I've found this article useful because I firmly believe it's the librarian who encourages me constantly to catch up with my duties of publishing, although sometimes I cannot see the point of why I should invest as much effort in publishing, rather than procrastinating. The first aim of scientific publication is to build and share knowledge. Above this romantic, idealistic thinking, it must be clear to us our true motivations to publish, because over it, we have personal motivations. It's beneficial to us. Such a very good article made me to write more on this subject, so I eventually wrote a post to add a few thoughts to those mentioned in this paper: http://www.rafalinux.com/thesis/articles/25/why-should-i-publish Thank you.


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    1. On 2015 Sep 17, BSH Cancer Screening, Help-Seeking and Prevention Journal Club commented:

      The HBRC Journal Club reviewed this paper, which investigates the effects of a decision aid administered in primary care on men’s intention to undergo prostate cancer screening. The authors conducted a randomised trial in a large number of general practices in France, in a mix of rural and urban areas. The topic intersects with several challenging and controversial areas of public health policy.

      The authors report that the intervention (consisting of a double-sided sheet of A4 describing various aspects of PSA testing) reduced the proportion of recruited men who intended to be screened for prostate cancer. However, although the study is stated to be a pragmatic trial, it is unclear how the intervention and associated findings apply to standard practice. Specifically, men appear to have been provided with the decision aid despite having given no indication that they were interested in PSA screening or concerned about prostate cancer, whereas these are the scenarios in which a decision aid is more likely to be used (notwithstanding possible differences between general practice in the UK and France). It is likely that men who spontaneously raise the issue of PSA screening with their general practitioner have preconceptions about the harms and benefits that are different to men who are not yet aware of it, which would lead them to respond to the decision aid quite differently. Moreover, the control condition, in which participants received only a questionnaire about prostate screening, may have had the paradoxical effect of increasing intentions among men who had not previously been considering prostate screening by raising the option without giving any indication of the associated harms.

      We also discussed characteristics of the decision aid itself. Inevitably, designing information for lay people involves a balance between competing priorities: it needs to be concise enough to be manageable within a given context (general practice, in this case) but comprehensive enough to convey all the desired detail. It also needs to be comprehensible to the target audience, most of whom will not be familiar with medical terminology or statistics. These competing trade-offs are made clear in this study, in which it appears that brevity has been prioritised over completeness. For example, we noted that there is no explicit information about the (limited) benefits of PSA screening on the first page of the decision aid, nor is there an estimate of the risk of false positives and overdiagnoses within the icon array. One might take the principled view that it is important to provide this information in order for men to be able to make an informed choice. Alternatively, one might take a pragmatic view that such information would burden participants with unnecessary detail. However, what constitutes the optimal method is subject to debate and is often a matter of personal opinion.

      A strength of the design was the follow-up question on the reasons underpinning participants’ screening intentions since this highlighted some of the specific viewpoints that were altered by the intervention. However, the study was limited by omitting a measure of knowledge, which is a necessary component of informed decision-making. For example, the study could have assessed whether the intervention was successful in terms of making participants aware of the possibility of overdiagnosis and lack of evidence to support a reduction in all-cause mortality.

      The HBRC Journal Club found this to be an interesting study, which benefited from its large sample size, randomised design and ‘intention reasons’ as a secondary outcome measure. However, it was limited by unclear applicability to standard practice and lack of additional secondary outcomes. In particular, this study illustrates the challenges of generating universally accepted information about screening.

      Conflicts of interest. We report no conflict of interests and note that the comments produced by the group are collective and not the opinion of any one individual.


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    1. On 2015 Aug 24, Eiko Fried commented:

      We have published a commentary on this article in Frontiers of Psychiatry, in which we introduce Symptomics as a novel research paradigm for psychiatry and clinical psychology. We provide a brief summary of the commentary below.

      Summary:

      "Research has now shown that distinct depression symptoms differ in the risk factors that predispose them, their underlying biology, their response to specific life events, and their impact on impairment of psychosocial functioning. The recently published work by Hieronymus et al. adds the differential reactivity of depression symptoms to antidepressant medication to this prior body of work. The authors argue that the findings stress the importance of analyzing individual depression symptoms in future studies. We would like to extend their claim: these results mandate the examination of symptom-specific effects throughout the realm of psychopathology. Symptomics invites the application of new modeling efforts to the level of individual symptoms as fundamental building blocks of mental disorders. Focusing (A) on the level of symptoms and (B) analyzing the causal relations among them—as an alternative approach to the dominant focus on diagnoses—is likely to extend our understanding of psychopathology directly and significantly. As such, symptomics may herald a time of renewed research energy that could, finally, provide an inroad to achieve real understanding of the mechanisms underlying psychopathology."

      Reference:

      Fried EI, Boschloo L, van Borkulo CD, Schoevers RA, Romeijn J-W, Wichers MC, de Jonge P, Nesse RM, Tuerlinckx F, & Borsboom D (2015). Commentary: "Consistent superiority of selective serotonin reuptake inhibitors over placebo in reducing depressed mood in patients with major depression", Frontiers in Psychiatry 6, 1–3. DOI: 10.3389/fpsyt.2015.00117.

      URL: http://journal.frontiersin.org/article/10.3389/fpsyt.2015.00117/full


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    1. On 2015 Sep 16, Geriatric Medicine Journal Club commented:

      This is an importnat trial fo HZ/su, a a subunit vaccine containing varicella-zoster virus glycoprotein E and the AS01B adjuvant system. Post-herpetic neuralgic can be a disabling event in the elderly. This article was critically appraised at the August 2015 Geriatric Medicine Journal Club (follow #GeriMedJC on Twitter). One of the study authors was also present for the live discussion. The full discussion can be found at: http://gerimedjc.blogspot.com/2015/09/study-author-joins-us-for-successful.html?spref=tw This trial shows promise particularly in the older old where Zostavax has waning efficacy. Approval, price, and coverage remain to be determined.


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    1. On 2017 Aug 25, Lance Turtle commented:

      This review states that it addresses the safety and immunogenicity of three vaccines manufactured in China, two inactivated (one PHK derived, the other Vero cell derived) and the live attenuated JE vaccine SA14-14-2. However, table 2 references Feroldi et al 2012 (PMID: 22777096), which is a study exclusively of the chimeric JE vaccine (Imojev) and does not include live vaccine SA14-14-2.

      The references appear to be mislabelled which may account for some of the confusion, e.g. the section entitled “safety of the three vaccines” refers to the same paper by Feroldi et al (using a different number) as a source of data for the inactivated vaccine safety analysis.

      Although the discrepancy might be accounted for purely by mis-referencing, table 2 refers to two papers by Feroldi et al, only one of which contains any data on the vaccines under review. Therefore, I suspect that the analysis of data on the live vaccine SA14-14-2 has been contaminated by inclusion of data on another vaccine not specified in the authors’ review strategy. The usefulness of this review is questionable unless these discrepancies can be corrected, and the paper re-referenced (as far as I can see all of the references in the tables are wrong).


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    1. On 2016 Mar 12, Kjartan Vaarbakken commented:

      Thanks for your enourmous effort undertaking this review on laser therapy for knee osteoarthritis (OA).

      In an attempt to add some to the discussion by looking for dose-response relationships, I suggest that laser with continuous output of 100 to 800 mW, energy density of 48 to 50 J/cm2, and energy per point of 6 J - all performed 2 times a week - may be the thing to try in the next laser trial on knee OA? Maybe the World Association of Laser Therapy guideline has underestimated the energy needed to effectively treat an osteoarthritic knee joint? Or maybe there is deeper tissues within the joint being reached by putting in more light energy? As cartilage and bone? Or, the fact that higher laser doses is needed for anti-inflammatory effects, a high energy deliverance may be the right stimuli to impair a synovial inflammation?

      Please take a look at this link supposed to illustrate a possible dose-respons relationship: https://twitter.com/kvaarbakken/status/708593031998533634

      Best regards, Kjartan Vaarbakken Physiotherapist, MSc, PhD student Norwegian University of Science and Technology Trondheim, Norway http://www.ntnu.edu/employees/kjartan.varbakken


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    1. On 2016 Jun 24, Maddalena Boccia commented:

      On the behalf of all the authors, I must report that the paper refers to a study performed when no bug has yet been reported in GingerAle 2.1.1 and has been published online on Aprile 2015 (accepted on April 2nd 2015), well before the bug description. Thus, there is no way to avoid this referred bug. However, taking in to account the comment posted on Pubmed 1 week ago (we are sorry to see it only now, but we haven’t received any notification about this) about results showed in the present publication, we re-run the analyses with the GingerAle 2.3.6 version, using a cluster-level inference, that it is consider the most appropriate method for statistical inference in ALE meta-analysis at this moment (Eickhoff et al., In Press “Behavior, sensitivity, and power of activation likelihood estimation characterized by massive empirical simulation” NeuroImage). We find that the main corpus of results did not change and our main conclusion, that is that specific neural networks of brain areas underpin PTSD after different traumatic events and that these networks may be related to specific aspects of the traumatic events is undoubtedly valid. In order to clear any doubt, we are considering to report the results with the last GingerAle version in a Letter to Editor, a form of scientific communication which allows to properly comment any scientific doubt raised by a paper in a polite and data-founded/evidence-based way


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    1. On 2015 Sep 28, Gauthier Bouche commented:

      The placebo-controlled randomized trial reported in this article explores the effects of anti-inflammatory drugs (steroidal and non-steroidal) on the inflammation induced by surgery of rectal cancer. Knowing the critical role that the peri-operative period may have on long-term cancer outcomes (Horowitz M, 2015), results of this trial are of major importance for clinicians and researchers interested in this topic. Since the full article is only available in Chinese, it is important to report the number of recurrences in each of the group as only the final p-value is reported in the abstract. The number of recurrence was 1, 3 and 3 in group A (celecoxib), group B (methylpredinosolone) and group C (placebo) respectively. The statistical test used was a Chi-square test. In the method section, the authors do not specify any statistical hypothesis (power calculation) for the recurrence endpoint. Therefore the conclusion of the author that celecoxib does not lower postoperative recurrence rate of rectal cancer is not supported by the results. The trial was not sufficiently powered to detect a difference (even a large one).


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    1. On 2015 May 20, James C Coyne commented:

      The registration of this trial http://www.isrctn.com/ISRCTN26666654 clearly states the hypothesis that mindfulness-based cognitive therapy (MBCT) with support to taper/discontinue antidepressant medication is superior to maintenance antidepressant medication in preventing depression over 24 months. No rationale is given for anticipating the superiority of MBCT, but it clearly was not achieved in the present study in terms of any primary or secondary outcomes. Nonetheless, this article proclaims the finding of no differences as an achievement. The study has been widely publicized in the media as demonstrating that there are no differences between MBCT and antidepressants, which is clearly not a conclusion justified by the design or the results.

      The claims of the present article require a noninferiority design which requires, in turn, a much larger sample size.

      In a blog post http://blogs.plos.org/mindthebrain/2015/05/20/is-mindfulness-based-therapy-ready-for-rollout-to-prevent-relapse-and-recurrence-in-depression/, I detail a number of concerns about this study and suggest it does little to fill the gaps in what little we know about tapering depressed patients receiving antidepressants in primary care. The patients who were recruited to the study were judged by semi structured research diagnostic interviews to be in remission, but their status at the time of prescription of antidepressants is only reconstructed retrospectively. Primary-care physicians typically do not make decisions to prescribe antidepressants on the basis of a formal semi structured interview with symptom counts.

      This article provides no report of the treatment received by patients assigned to the maintenance antidepressant group and what quality and quality of care they received or even their adherence at the start of the study. Some studies suggest that a substantial proportion of primary care patients are already nonadherent six months after their initial prescription of antidepressants.

      NICE guidelines recommend maintenance therapy for two years, but these guidelines are based on experiences in tertiary specialty psychiatric populations where the course of depression may be more severe and the risk of relapse greater. Arguably, a descriptive observational study would’ve been less expensive and more informative if it assessed adherence, contact with providers, and symptoms and side effects of primary care patients who were prescribed antidepressants a year earlier.

      Results of this study would be much more informative if there had been better description of the care received in the control group or, better, a comparison/control group that provided equivalent amounts of attention, contact time, and support. It could well be that a specialized depression care manager with less training could have achieved equivalent results. Moreover, we simply don’t know if physicians advising their remitted patients to taper antidepressants would have achieved the same results.


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    1. On 2015 Apr 25, Martin Turner commented:

      This should be an interesting study, but I suspect the results may be ambiguous. I think you may be giving your diet group too much sodium. 3 g of sodium is 130 mmol which is close to average sodium intake. Extracellular fluid expands when sodium intake exceeds approximately 800 mg or 35 mmol/day (Freis. Circulation 53(4):589-595 1976). This study will require a substantial effort and it would be worth reducing the sodium intake of your diet group to approximately 800 mg or 35 mmol/day.


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    1. On 2015 May 02, Donald Forsdyke commented:

      DIABETIC PLASMA IS MORE ROULEAUGENIC THAN NORMAL PLASMA This fine paper reports an impressive in vivo method for evaluating rouleaux formation. The authors correctly state that rouleaux formation is "attributed to some changes in the plasma concentration" of certain proteins, "which modify the interaction between RBC." However, they go on to conclude that "diabetic erythrocytes have a higher propensity to form aggregates." To show this they would have had to study both RBCs from diabetic patients in normal subjects’ plasma and the converse (normal RBCs in diabetic patients’ plasma). But they do not report such experiments.

      Following their original premise, it would be predicted that, when suspended in plasma from diabetic patients, normal RBC (of the same blood group) would form rouleaux just as well as the RBC from diabetic patients. That the primary change is in the surrounding plasma has long been known. Indeed, normal plasma can be made rouleaugenic by either heating to generate polymeric albumin, or merely by slightly concentrating. In both circumstances, the plasma will aggregate autologous RBC (1).

      It appears that the aggregation is entropy-driven, showing a degree of specificity (like-RBC aggregating with like-RBC) analogous to the homoaggregation of macromolecules that can be induced by increasing the concentrations of surrounding but dissimilar macromolecules (2). The early history and theoretical implications of rouleaux formation are reviewed elsewhere (3), and in my webpages: see Entropy-Driven Protein Self-Aggregation at http://post.queensu.ca/~forsdyke/mhc001.htm

      (1) Forsdyke DR, Palfree RGE, Takeda A (1982) Formation of erythrocyte rouleaux in preheated normal serum: roles of albumin polymers and lysophosphatidylcholine, Canadian Journal of Biochemistry 60: 705-711.

      (2) Forsdyke DR, Ford PM (1983) Segregation into separate rouleaux of erythrocytes from different species. Evidence against the agglomerin hypothesis of rouleaux formation. Biochemical Journal 214: 257-260.

      (3) Forsdyke DR (1995) Entropy-driven protein self-aggregation as the basis for self/not-self discrimination in the crowded cytosol. Journal of Biological Systems 3: 273-287.


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    1. On 2016 Oct 19, David Nunan commented:

      We wrote an editorial on this open access editorial but ours was put behind a paywall. In addition, the open access editorial also received the following: - numerous promotional tweets from the @BJSM account (ours received one at the time of its release) - a podcast https://soundcloud.com/bmjpodcasts/you-cant-outrun-a-bad-diet-draseemmalhotra-on-weight-loss-strategies - Reference in a blog http://blogs.bmj.com/bjsm/2015/05/21/its-not-just-bjsm-talking-about-healthy-nutrition-real-food/

      To attempt to redress the balance, here we provide an abriged pre-published version of our editorial piece for interested readers.

      Malhotra and colleagues highlight the important health benefits of physical activity in cardiovascular disease, type 2 diabetes, dementia and cancer but dismiss any benefit for weight loss in obesity.1 However, the poor use of existing evidence to underpin this dismissal and the resultant press release generated headlines that send a misleading message to patients and the public.

      Poor use of evidence.

      An evidenced-based approach to clinical decision making involves understanding the best type of evidence to use, how to appraise it, and assessing its usefulness in practice. Such an approach determines the risk of bias and ensures decisions are guided by accurate, meaningful evidence. The GRADE guidelines cite expert opinion alone as very low quality evidence, with a high risk of bias.2 Unfortunately much of the evidence cited by Malhotra and colleagues was based on expert opinion or was not referenced. For example, when excluding a relationship between obesity and physical activity, the evidence cited was an opinion piece by Luke & Cooper3, which has been criticised for ignoring observational and experimental studies that support a relation between physical activity and obesity. They give no reference for their claim that according to the Lancet Global Burden of Disease report poor diet now generates more disease than physical inactivity, alcohol, and smoking combined.

      Current recommendations for physical activity in obese patients.

      To substantiate their dismissal Malhotra and colleagues would have to provide better evidence to justify why current guidance is wrong. The World Health Organisation currently recommends that obese and overweight individuals engage in regular physical activity (60 minutes a day for children and 150 minutes per week for adults).4 National Institute for Health and Care Excellence (UK) guidance advises health professionals should support obese patients in increasing their physical activity, particularly through activities that fit easily into their everyday life.5 Recognising the value of physical activity in promoting a healthy lifestyle, including in obese patients, the Academy of Medical Royal Colleges recently issued its report Exercise: the Miracle Cure, which summarised the evidence on physical activity and called on doctors “to promote the benefits of regular physical activity to their patients and to communities in their wider roles as ‘advocates for health’.”6 They also highlight systematic review evidence that body weight may stay the same despite a reduction in high risk visceral fat as a result of increased muscle mass.

      Current evidence for physical activity and obesity.

      The Malhotra editorial challenges the effectiveness of physical activity for weight loss in obese individuals. The guidelines and reports highlighted above present much of the evidence base and include a specific Cochrane systematic review by Shaw and colleagues7 which was ignored by the Malhotra editorial. This review included 43 studies reporting results from 41 randomised controlled trials including a total of 3476 participants. The duration of included studies ranged from 3 to 12 months (61% less than 4 months), including follow-up. Although methodological quality for included studies was variable according a risk of bias assessment, the Cochrane review authors report that exercise combined with diet resulted in greater weight reduction than diet alone (mean difference -1.0 kg; 95% confidence interval (CI), -1.3 to -0.7). They also note the finding that increasing exercise intensity increased the magnitude of weight loss (mean difference -1.5 kg; 95% CI -2.3 to -0.7). An additional finding was that exercise improved a range of secondary outcomes even when weight loss did not occur. The authors conclude exercise was an effective weight loss intervention, particularly when combined with dietary interventions but make no inference to the poor quality of included trials and little reference to the fact that diet alone appeared better than exercise alone (mean difference -3.6 kg, 95% CI -4.3 to -3). Whether these differences are meaningful requires good clinical judgement and open, honest discussion.

      These outcome and quality findings are repeated in a more recent systematic review assessing treatment (including diet, exercise or diet and exercise) for overweight and obesity in adult populations.8 When objectively assessing the best available evidence, for which we acknowledge the majority is of low quality, it would appear that diet alone (mainly low fat) is better than exercise alone but diet and exercise both are better than either. A further key point is that improvements in important health risk factors are observed with exercise even without weight loss.

      Conclusions

      There is little doubt that diet is key in the management of the obesity epidemic. What is less helpful, and does no-one, including the public and patients, any favours, is the production of opinion pieces that use evidence poorly or not at all.

      References 1. Malhotra A, Noakes T, Phinney S. Editorial: It is time to bust the myth of physical inactivity and obesity: you cannot outrun a bad diet. Br J Sports Med doi:10.1136/bjsports-2015-094911 2. Howard Balshem Mark Helfand, Holger J. Schünemann, Andrew D. Oxman, Regina Kunz, Jan Brozek, Gunn E. Vist, Yngve Falck-Ytter, Joerg Meerpohl, Susan Norris, Gordon H. Guyatt. GRADE guidelines: 3. Rating the quality of evidence July 30, 2010; Published Online: January 06, 2011 3. Luke A, Cooper RS. Physical activity does not influence obesity risk: time to clarify the public health message. Int J Epidemiol 2013; 42(6): 1831-6. 4. http://www.who.int/mediacentre/factsheets/fs311/en/. Accessed 28 April, 2015 5. http://www.nice.org.uk/guidance/cg43/resources/guidance-obesity-pdf. Accessed 28 April, 2015 6. http://www.aomrc.org.uk/general-news/exercise-the-miracle-cure.html. Accessed 28 April, 2015. 7. Shaw KA, Gennat HC, O’Rourke P, Del Mar C. Exercise for overweight or obesity. Cochrane Database of Systematic Reviews 2006, Issue 4. Art. No.: CD003817. DOI: 10.1002/14651858.CD003817.pub3. 8. Peirson L, Douketis J, Ciliska S, Fitzpatrick-Lewis D, Usman Ali M, Raina P. Treatment for overweight and obesity in adult populations: a systematic review and meta-analysis CMAJ Open. 2014 Oct-Dec; 2(4): E306–E317. Published online 2014 October 1. doi: 10.9778/cmajo.20140012.


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    1. On 2016 Jan 04, Amanda Capes-Davis commented:

      Anyone who uses MDA-MB-435 to study breast cancer needs to be aware that MDA-MB-435 comes from the same donor as M14, a widely used melanoma cell line. Although the origins of MDA-MB-435 and M14 continue to be debated, a strong body of evidence exists to say that MDA-MB-435 is misidentified and is actually melanoma.

      Concerns regarding the origin of MDA-MB-435 were first raised by Ross et al., 2000 (PMID 10700174). This cDNA microarray analysis of the NCI-60 cell line panel showed that MDA-MB-435 closely resembled melanoma cell lines rather than breast. Rae et al. (PMID 15679052, 17004106) later demonstrated that MDA-MB-435 shares a common origin with the M14 melanoma cell line. Numerous samples of both cell lines have been tested with the same finding.

      This finding has been debated based on phenotypic evidence. The article above notes that MDA-MB-435s expresses LHRHR. MDA-MB-435 has previously been shown to express other breast-specific markers e.g. Sellappan et al., 2005 (PMID 15150101). However, it should also be noted that MDA-MB-435 expresses melanoma-specific markers e.g. Ellison et al., 2002 (PMID 12354931).

      Phenotype can be helpful but is often confusing when looking at misidentified cell lines. For example, cell lines that are cross-contaminated with HeLa have been shown to express liver- and other tissue-specific markers, leading to the incorrect assumption that cell lines are authentic when they are actually HeLa derivatives e.g. Chang, 1978 and response by Nelson-Rees, 1978 (PMID 622561). It is important to make any phenotype-based decisions using a broad expression profile and not rely on one or two individual markers.

      It is also essential to test for donor origin using a method such as short tandem repeat (STR) profiling. STR profiling makes it clear that MDA-MB-435 and M14 share a common donor origin; review of their origins show that one of these cell lines must be misidentified.

      Donor origin continues to be a subject of debate for MDA-MB-435 e.g. Chambers, 2009 (PMID 19549886). Users of MDA-MB-435 must make decisions based on available data. In my view, MDA-MB-435 is an unsuitable model to study breast cancer and the model described above is more likely to be suitable for melanoma research.


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    1. On 2017 Nov 24, Amanda Capes-Davis commented:

      Following up from the comment by Deilson Elgui de Oliviera, ICLAC has new data on MDA-MB-435 and its origin (https://www.ncbi.nlm.nih.gov/pubmed/28940260).

      MDA-MB-435 came from the same donor as M14, a cell line that was established from a male with melanoma. Most publications have concluded that MDA-MB-435 is misidentified but the topic has been a controversial one. MDA-MB-435 can express breast-specific markers and its karyotype is XX, which would fit with its reported origin from a female with breast cancer.

      ICLAC went back to the original publications for these two cell lines and found that M14 was established and submitted for publication before MDA-MB-435. The originator, Dr Donald Morton, established a specimen repository at the John Wayne Cancer Institute (JWCI); we contacted JWCI to ask if early specimens were available. JWCI was able to supply early samples of the M14 cell line, a lymphoblastoid cell line from the same donor (ML14), and serum from the melanoma donor dating back to 1973. The originator's work made subsequent testing possible.

      Testing of these early samples showed that MDA-MB-435 came from the M14 donor, proving that MDA-MB-435 is misidentified. The XX karyotype was caused by chromosomal rearrangement; the donor's lymphoblastoid cell line is XY.

      This "Tale of Two Cell Lines" is a cautionary tale showing that phenotype can be misleading when working with cell lines. Always test your cell lines for authenticity. A cell line is itself a variable that can never be taken for granted.


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    1. On 2016 Aug 23, Ben Goldacre commented:

      This trial has the wrong trial registry ID associated with it on PubMed: both in the XML on PubMed, and in the originating journal article. The ID given is NCT0131821. We believe the correct ID, which we have found by hand searching, is NCT01318213.

      This comment is being posted as part of the OpenTrials.net project<sup>[1]</sup> , an open database threading together all publicly accessible documents and data on each trial, globally. In the course of creating the database, and matching documents and data sources about trials from different locations, we have identified various anomalies in datasets such as PubMed, and in published papers. Alongside documenting the prevalence of problems, we are also attempting to correct these errors and anomalies wherever possible, by feeding back to the originators. We have corrected this data in the OpenTrials.net database; we hope that this trial’s text and metadata can also be corrected at source, in PubMed and in the accompanying paper.

      Many thanks,

      Jessica Fleminger, Ben Goldacre*

      [1] Goldacre, B., Gray, J., 2016. OpenTrials: towards a collaborative open database of all available information on all clinical trials. Trials 17. doi:10.1186/s13063-016-1290-8 PMID: 27056367

      * Dr Ben Goldacre BA MA MSc MBBS MRCPsych<br> Senior Clinical Research Fellow<br> ben.goldacre@phc.ox.ac.uk<br> www.ebmDataLab.net<br> Centre for Evidence Based Medicine<br> Department of Primary Care Health Sciences<br> University of Oxford<br> Radcliffe Observatory Quarter<br> Woodstock Road<br> Oxford OX2 6GG


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    1. On 2015 Apr 26, Donald Forsdyke commented:

      The data in this interesting paper seem not incompatible with the hypothesis that the need to prevent recombination with other organisms drives a organisms GC%. This anti-recombination selective effect (resulting in the reproductive isolation needed for maintaining species integrity) is something the entire organism has to adapt to. Having adapted, it seems not unlikely that, in some cases, an artificial changing of GC% (as in the Kelkar paper) would be deleterious. This would be particularly evident in the case of 'lower' species that had not superimposed other mechanisms for maintaining reproductive isolation. Absence of superimposed mechanisms would prevent GC% values from seeking new equilibrium positions. For more see my text Evolutionary Bioinformatics (Springer, New York, 2011).


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    1. On 2016 Jun 23, Francisco Felix commented:

      Unfortunately, methodology section seems to be faulty in this publication. Some of the information I did not find when reading it: 1. What was the administration scheme of naringin (once daily, weekly, other)? 2. What was the dose of cisplatin used (as unlikely as it seems to be, the authors really have forgotten to report it)? 3. Have the behavioral tests been done 48 or 24h prior to animal killing? Both contradictory information were given. I am afraid this paper is not really useful without clarification upon these issues, once they are critical for the methodology the researchers used. Maybe editorial and peer reviewing process could have been a little more rigorous in this case? I disclose no conflicts of interest.


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    1. On 2015 Apr 25, David Keller commented:

      Unfortunately, this study did not measure any relevant clinical outcomes, such as weight loss

      This study reports that subjects who consumed thlylakoids (a spinach extract) had reduced hunger, increased satiety, reduced cravings for snacks, and other purely subjective measures. There was no reported improvement in clinically important outcomes, such as: actual weight loss; body fat composition; waist-to-hip ratio; lipid profile; blood sugar levels, and so on. It is common knowledge that consuming French pastries also reduces hunger, increases satiety and reduces cravings for snacks. What is needed is an intervention proven to reduce subjective cravings for food while promoting actual weight loss and other outcomes which directly affect health. This study does not present any clinical evidence to support the authors' recommendation that thylakoids be used as a food supplement.


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    1. On 2015 Sep 20, Eythor Kristjansson commented:

      The paper (Meisingset et al. BMC Musculoskeletal Disorders (2015) 16:56 DOI 10.1186/s12891-015-0517-2) reports the findings of a cross-sectional study, which examined set of tests to investigate cervical motor control. One of the tests that were used was the Fly Test©, which Meisingset et al cited “as described by Kristjansson et al., 2010” [1]. When I read the abovementioned article by Meisingset et al., [1] I found out that their article does not replicate the study by Kristjansson & Oddsdottir 2010, at all [2]. There are two main crucial differences in Meisingset et al. study and the original study by Kristjansson & Oddsdottir, 2010 [2], which make these 2 studies incomparable. First, there are several inbuilt parameters in the patterns in the original Fly Test©, and it is impossible for Meisingset et al., to know what inbuilt parameters were used and how we used these parameters. Meisingset et al. just copied the geometry of 2 patterns without permission from the publisher. Second, Meisingset et al. methodology is completely different from ours. Research results using different inbuilt variables within the patterns and completely different methodology can never be comparable. It is therefore not surprising that Meisingset et al. study found no difference in the performances between controls and neck pain group, besides that the controls performed worse in one sequence of what Meisingset et al., misleadingly call “the Fly Test”. Following are the main differences in methodology of the 2 studies: 1. Set-up: Our original study used a seated position, 1m from the screen whereas Meisingset et al. used standing position, 2.5m from the screen. It can be easily proven mathematically that different angles are produced on the screen depending on the patients distance from the screen. This alone will generate different results as longer distance (2.5 m) will produce narrower angle on the screen i.e. lesser ROM than a distance of 1m, as we used in our original paper. 2. Number of patterns and repetitions: Our original study used three patterns, easy-medium-difficult of uniform size and three repetitions for each pattern in random order, altogether 9 trials. Meisingset et al. used two patterns, easy and medium with 2 trajectory sizes; on smaller and one bigger. Furthermore, the control group in Meisingset et al study just performed the patterns once, while the neck pain group performed the patterns twice, not in random order. 3. Duration of patterns: Our original study used 25, 40, and 50 seconds for the easy-medium-difficult patterns, respectively whereas Meisingset et al. used 30 seconds for both patterns; easy and medium. Here, Meisingset et al. wrongly cited our original paper; see Table 1 in their study [1]. The velocity in Meisingset et al. study for the medium pattern must therefore be faster than in the easy pattern as longer distance is traveled in the medium pattern. I have one more serious concern about Mesingset et al. conclusion regarding what they misleadingly call “the Fly Test” in their study: In the Discussion section, Meisingset et al. cited Oddsdottir et al. 2013, regarding gender difference. Meisingset et al. write on p. 11 under the heading Trajectory movement control: “In the HC group (Healthy Control) we found that females had a consistently larger deviation in the Fly test compared to men in the HC group suggesting that the group differences in Kristjansson & Oddsdottir study, 2010 may be influenced by the different gender distribution in the groups”. Meisingset et al. continue: “However, Oddsdottir et al. found similar results between healthy females and men for the same Fly test [3]”. “This discrepancy between the studies requires further investigation before this test can be implemented in clinical practice.” Meisingset et al. are making reference to our database study [3]. The result section on p. 3 in our database study starts on the following statement: “The multivariate analysis of variance indicated a statistically significant effect for age (p < 0.001), but not for gender (p > 0.05). Therefore normative data were only distributed according to age”. It is impossible for us to understand how Meisingset et al. can cite our work in such a wrong way. References [1] Meisingset I, Woodhouse A, Stensdottir A-K, Stavdahl Ö, Lorås H, Gismervik S, Andersen H, Austreim K, Vasseljen O, Evidence for a general stiffening motor control pattern in neck pain: a cross sectional study. BMC Musculoskeletal Disorders (2015) 16:56 DOI 10.1186/s12891-015-0517-2 [2] Kristjansson E, Oddsdottir G."The Fly" - A new clinical assessment and treatment method for deficits of movement control in the cervical spine: reliability and validity. Spine 2010; 35: E1298–E1305 [3] Oddsdottir G, Kristjansson E, Gislason M. Database of movement control of the cervical spine: Reference normal of 182 asymptomatic people. Manual Therapy 2013; 18: 206–210.

      Competing interests: EK is the founder of NeckCare Ltd, a start-up innovation company developing the Fly Method©, and other innovative methods, for diagnostic and treatment purposes. The tasks created in the new Fly Method© are protected by patent rights.

      Meisingset I, 2015 http://www.nih.gov NIH Home


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    1. On 2016 Jan 12, Elaine Beller commented:

      This is a topic that has been debated on my Facebook feed recently. This group has performed a RCT, but reports within-group changes throughout, and not the between-group results. Some of the within-group results have P-values less than 0.05, and these are the ones that been reported in the abstract. This approach implies that there were no changes in the control group, and that both groups had similar baseline values (which is not so). I suggest the authors should give the results for the comparison between groups on final value, adjusted for baseline (ANCOVA).

      Bland and Altman have written several excellent artcles explaining why the within-groups approach should not be used. In one which is open-access, they say: "This approach is biased and invalid, producing conclusions which are, potentially, highly misleading. The actual alpha level of this procedure can be as high as 0.50 for two groups...",

      Comparisons against baseline within randomised groups are often used and can be highly misleading. Trials 2011, 12:264 doi:10.1186/1745-6215-12-264


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    1. On 2016 Dec 15, Morten Oksvold commented:

      This article has been retracted due to several problematic issues with data duplications.

      This case represents an excellent example for how an editorial and review process should NOT be performed:

      1. Apparent extensive duplication of data was not detected during the review process.
      2. Three issues of apparent duplications were reported to Science by Johannes M Dijkstra June 25th 2015.
      3. Dijkstra reported to Science regarding a fourth apparent data duplication August 13th.
      4. Science confirmed that they will publish a correction of the reported duplications September 24th.
      5. Science published a correction October 23rd 2015.
      6. The published correction poorly describes the details of the correction and the general explanation for how the published duplications were made is difficult to understand.<br>
      7. The extensive correction was not discussed with the authors' research institutes.
      8. Apparent data duplication in the corrected version was reported November 18th.
      9. Science published an expression of concern December 10th. Imperial College London investigates the case.
      10. Science finally retracted the article one year later (December 10th).
      11. The published retraction is only accessible for subscribers.

      Please see the full discussion at PubPeer:

      https://pubpeer.com/publications/B74CF2D21C4A180A5685A30DC06D29#fb113276


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    1. On 2016 Mar 03, Farrel Buchinsky commented:

      An interesting article about 21 children noting that there was a correlation between the number of surgeries and the preceding delay between symptoms developing and a diagnosis being made. This finding would be compatible with the possibility that the longer one delays the more a child is likely to need more surgeries. If that is true then that should encourage us to make the diagnosis as soon as possible so that we can operate as soon as possible and so that the child could undergo fewer surgeries rather than more surgeries. Given that this was not a randomized trial would the data also be compatible with another possibility? Could it be that children with the least delay may have gone into spontaneous remission had their delay continued and they had undergone no surgery?

      Two other observations struck me when I looked at the data. There was a statistically significant association between the age of symptom onset and the time between symptom onset and diagnosis. Children whose symptoms began before they were 5.5 y (66 months) had a median delay of 33 months and the children who were older than 5.5 y when their symptoms began had a median delay of 3.5 months. Many case series have demonstrated an association between younger age being associated with a more aggressive clinical course presumably resulting in greater number of surgeries. That was not seen in this group of 21 patients.

      Can you please check the statement, "The average time from symptom onset to diagnosis was 52.3 months". I calculate it to be 20.3 months. I used the following values: 1 3 24 7 33 36 48 3 4 4 54 7 21 26 38 3 43 59 1 1 10


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    1. On 2015 May 31, Amanda Capes-Davis commented:

      Delighted to see that the STR profiles produced in this study are now available through the NCBI BioSample database (http://www.ncbi.nlm.nih.gov/biosample/). BioSample users can browse human cell line STR profiles and also look for known misidentified cell lines. At the time of writing there are 2992 STR profiles entered into BioSample, meaning that a wide variety of cell lines now have STR profile information available.

      Many thanks to NCBI staff for their work in providing this resource!


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    1. On 2015 Apr 23, Christopher Southan commented:

      This is a valuable commentary but overlooks the importance of, as an adjunct to improved general transparency, also openly declaring the molecular structures of new therapeutic agents used in these trials. This aspect is detailed in "Challenges and recommendations for obtaining chemical structures of industry-provided repurposing candidates" http://www.ncbi.nlm.nih.gov/pubmed/23159359


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    1. On 2016 Aug 30, Ben Goldacre commented:

      This trial has the wrong trial registry ID associated with it on PubMed: both in the XML on PubMed, and in the originating journal article. The ID given is NCT0984021. We believe the correct ID, which we found in the text in an embedded link, is NCT01984021.

      This comment is being posted as part of the OpenTrials.net project<sup>[1]</sup> , an open database threading together all publicly accessible documents and data on each trial, globally. In the course of creating the database, and matching documents and data sources about trials from different locations, we have identified various anomalies in datasets such as PubMed, and in published papers. Alongside documenting the prevalence of problems, we are also attempting to correct these errors and anomalies wherever possible, by feeding back to the originators. We have corrected this data in the OpenTrials.net database; we hope that this trial’s text and metadata can also be corrected at source, in PubMed and in the accompanying paper.

      Many thanks,

      Jessica Fleminger, Ben Goldacre*

      [1] Goldacre, B., Gray, J., 2016. OpenTrials: towards a collaborative open database of all available information on all clinical trials. Trials 17. doi:10.1186/s13063-016-1290-8 PMID: 27056367

      * Dr Ben Goldacre BA MA MSc MBBS MRCPsych<br> Senior Clinical Research Fellow<br> ben.goldacre@phc.ox.ac.uk<br> www.ebmDataLab.net<br> Centre for Evidence Based Medicine<br> Department of Primary Care Health Sciences<br> University of Oxford<br> Radcliffe Observatory Quarter<br> Woodstock Road<br> Oxford OX2 6GG


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    1. On 2015 May 07, Ryan Radecki commented:

      Over 200,000 physicians belong to the American Medical Association. The Journal, therefore, of this Association has a significant audience and a long tradition. Continuing Medical Education inserts in JAMA may represent the basic education of many new developments for general practitioners.

      These authors perform a systematic review on “acute stroke intervention”. They identify and review 145 abstracts utilizing multiple combinations of MeSH terms and synonyms for “brain ischemia/drug therapy, stroke drug/therapy, tissue plasminogen activator, fibrinolytic agents, endovascular procedures, thrombectomy, time factors, emergency service, treatment outcome, multicenter study, and randomized controlled trial”. A massive undertaking, to be sure – considering these authors are also including intra-arterial and mechanical therapy in their review.

      Yet, as indicated in their evidence review chart in the supplement, these authors' strategy managed to identify only 17 RCTs – in the whole of systemic and endovascular therapy....

      http://www.emlitofnote.com/2015/04/a-laughable-tpa-systematic-review.html


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    1. On 2015 Jul 08, Radboudumc Psycho-Oncology Journal Club commented:

      This is a very interesting and clearly reported study that identifies which patients are more or less likely to participate in mindfulness-based stress reduction (MBSR), and the relationship between presence of and search for meaning and willingness to participate in MBSR. After discussing this paper in during our journal club meeting, the following points were raised:

      • 1. The results showed that being non-white is associated with higher levels of searching for meaning. As mentioned in the discussion spirituality and religious coping are important to African Americans. After reading the items of the subscale assessing search for meaning, such as ´I am seeking a purpose or mission for my life’, we wondered whether searching for meaning might be associated with spirituality or religiosity. We believe it would have been nice if a formal assessment of spirituality or religiosity had been included in this study.
      • 2. Meaning making and psychological distress are closely related. As this is a cross-sectional study, we wondered about the direction of this relationship. Does higher distress lead to searching for meaning? Or does continuously searching for meaning lead to distress?
      • 3. We know from practice that it is sometimes difficult to explain the rationale of MBSR to patients who might benefit from it. We read that participants in current study received a written description of MBSR, however no further elaboration of patients’ understanding of the purpose and rationale for MBSR was given. We believe it would have been helpful if a greater degree of depiction was provided to the reader about patients’ knowledge and understanding of the content and purpose of MBSR.<br>
      • 4. Related to point 3, we also wondered about the order of the questionnaires. At what point patients were asked whether they were willing to participate in MBSR. At the beginning or the end of the questionnaires?
      • 5. Given the findings about significant role of ethnicity, and the potential for cultural factors to influence uptake of MBSR, some members of our journal club wondered whether the research staff enrolling patients in this study were white or non-white


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    1. On 2017 May 20, Jonathan Lalsiamthara commented:

      Dear Jean-Jacques Letesson,

      Thank you for your concerns on this manuscript. We could have replied to you sooner if the queries were forwarded to the given corresponding author and also updates regarding this topic could have been promptly relayed to you.

      1 Our interest was to generate O-PS shortened S19 strain. Interestingly, this particular strain (IVRIGEBJ7) which has putative perosamine synthetase gene knocked-out has shown truncated O-PS profile. We also reported that it is rough intermediate (by comparing it with smooth and complete-rough strains) and proved that it is on the surface rather than inside cytoplasm. While we could have communicated with the strain name IVRIGEBJ7, to make it more meaningful we go by the target gene name 'per'. It can still be useful to report a potential vaccine candidate without knowing the actual genetic makeup, because historically S19 and RB51 have many unknown mutations when they were reported. Nevertheless, the whole-genome sequence (http://genomea.asm.org/content/3/6/e01336-15.full.pdf) of the mutant strain is now available on GenBank and complementation eventually confirmed the veracity of the mutation.

      2 Indeed there are two enzymes encoding perosamine synthetase. This manuscript reported knock-out of a putative one (which some workers may annotate it as wbkB). This might explain your concerns regarding “so called "per" mutant”, only that the enzymes are not exclusive to S19, but both are present across Brucella spp.

      3 It was discussed that similar “OPS profiles” i.e truncated OPS in PAGE- silver or -western blots were also observed in two given studies, delta pgm and RB51. The discussion did not claim anything about their phenotypes but related to their OPS properties. The typographical error should be “.. RB51 strain with wboA gene complemented”.


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    2. On 2017 Mar 23, Jean-Jacques Letesson commented:

      The basic scientific requirement to characterize a mutant is to prove that the phenotype characterized can be reverted to the WT phenotype by bringing in trans the WT gene.

      This has not be done in this study as no complementation was even evoked. Therefore the phenotype observed cannot be claimed as caused by the "per" deletion.

      There are in addition several fact in this paper that were either omitted, overinterpreted or even mistaken.

      1- Concerning the roughness of the so called "per" mutant

      -the O-PS of Brucella is an homopolymer of N-formylperosamine (meaning that the sole an unique sugar used to build the O-chain is this one) and that N-formylperosamine is the biosynthetic result of three sequential reactions catalyzed by enzymes (Gmd, per, Wbkc) encoded by three unique genes.

      -without "per" it is impossible to build a "bona fide" perosamine and thus an O-PS chain. In none of the Brucella species in which the "per" mutation has been tested, has a partial/shortened or whatsoever modified O-chain been described.

      -Considering that the S19 per mutant described in this paper is "mid-smooth" will thus need another gene encoding the "same" enzymatic activity that would only exist or be expressed in B. abortus S19 and not in any other Brucella species.

      -the epitopic composition of the O-PS should have been explored with a panel of MoAbs specific for Brucella O-PS and not with an uncharacterized polyclonal antibody that give a VERY POOR immunoreactivity on the O-PS of the WT S19

      2- To explain the (mid-smooth phenotype) and the truncated O-PS observed in the S19 per mutant, the authors evoke, in the discussion, that a similar observation was made for delta pgm of B. abortus S2308 and also for the B. abortus RB51 strain with wboA gene deletion mutation. THIS CLAIM IS ABSOLUTELY FALSE

      -the pgm mutant is completely ROUGH (but has an O-chain in the cytoplasm and is unable to link it to the core)

      -the wboA is completely ROUGH and in the reference they cite the strain is a complemented one that is still ROUGH but produce an O-chain in the cytoplasm. (Vemulapalli R, He Y, Buccolo LS, Boyle SM, Sriranganathan N, Schurig GG. Com-plementation of Brucella abortus RB51 with a Functional wboA Gene Results inO-Antigen Synthesis and Enhanced Vaccine Efficacy but No Change in RoughPhenotype and Attenuation. Infect Immun 2000;68:3927–32.)


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    1. On 2015 May 31, Amanda Capes-Davis commented:

      Please be aware that the KB cell line and any derivatives do NOT come from oral carcinoma. KB is known to be misidentified and is actually HeLa, from cervical carcinoma. It is important to test for misidentified cell lines; this can be done using authentication testing. Short tandem repeat (STR) profiling is a consensus test method that allows you to check for misidentification of human cell lines.

      KB is widely used in the scientific literature as an oral cancer cell line. It would be impossible to manually add comments to all abstracts that use the cell line as an oral cancer model. Journals such as Nature now require authors to check against published lists of known misidentified cell lines, and report on authentication testing. This approach will help to address the problem.

      The International Cell Line Authentication Committee (ICLAC) maintains a list of known misidentified cell lines at http://iclac.org/databases/cross-contaminations/.


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    1. On 2015 Apr 24, Pertti Hakkinen commented:

      Readers may also want to look at (but it is not in indexed in PubMed): Curry, K. K., D. J. Brookman, G. K. Whitmyre, J. H. Driver, R. J. Hackman, P. J. Hakkinen, and M. E. Ginevan. (1994) "Personal Exposures to Toluene During Use of Nail Lacquers in Residences -- Results of a Preliminary Study." JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY 4: 443-456.


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    1. On 2015 Apr 22, Martine Crasnier-Mednansky commented:

      A diauxie was observed for the pair glucose-succinate (Lazzarini RA, 1971) therefore glucose and succinate most likely are not used simultaneously. Thus in keeping with the questionable reasoning by the authors, the growth rate on the glucose-succinate pair (Table 1) should not be higher than the growth rate on either glucose or succinate.

      The physiological relevance of the preceding article by You C, 2013, on which this report is based, was commented on in PubMed Commons.


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    1. On 2015 Apr 30, Nursing Innovation Journal Club commented:

      My junior honors class reviewed this paper as one the assignments. I thought I would engage the authors in a couple of questions raised during our discussions of your paper. 1- This is important work, particularly as there are many patient safety issues identified during the transition from hospital-to-home. Have the authors considered financial outcomes associated with interprofessional collaborative practice? What types of financial outcome variables would you like to see in future research? 2-The AHA recently posted new guidelines for treating patients with heart failure in long-term care facilities. paper 1-http://circheartfailure.ahajournals.org/content/8/2/384.short?rss=1&ssource=mfr paper 2-http://circheartfailure.ahajournals.org/content/early/2015/04/07/HHF.0000000000000005 How can your work in this paper be expanded to include outside organizations like long-term care, home health, etc.?


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    1. On 2016 Aug 10, Sander Houten commented:

      In our paper, we described the molecular basis of alpha-aminoadipic and alpha-ketoadipic aciduria by sequencing DHTKD1 in 10 cases. Case 6 was compound heterozygous for c.1364G>A and c.1159+5G>A. The c.1159+5G>A mutation is likely to affect splicing because it changes a conserved position in the splice donor site of intron 6. In follow up studies, we have now addressed the consequences of the c.1159+5G>A mutation on splicing. For this, we generated cDNA from peripheral blood mononuclear cells and characterized the DHTKD1 transcripts. Our results revealed two different DHTKD1 transcripts in this individual. One transcript had the c.1364G>A mutation and a second transcript lacked exon 6. From this we conclude that as predicted, the c.1159+5G>A mutation leads to skipping of exon 6.


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    1. On 2015 Oct 12, Simon Young commented:

      There are a number of problems in this paper in the interpretation of the results, and in the discussion of the previous research on which this study was based. 1. The paper does not mention that tryptophan is taken up into brain by a transport system that is active towards all the large neutral amino acids (LNAA). The other LNAA compete with tryptophan for uptake into brain. When protein is ingested the plasma level of tryptophan increase, but so do plasma levels of the other LNAA. As a result, ingesting normal dietary proteins, or increasing the protein content of the diet, will not raise brain tryptophan or serotonin synthesis, as discussed in many reviews, e.g. Fernstrom JD, 1994. This has been confirmed in a human study involving CSF measures as an approximation of what happens in the brain Teff KL, 1989. While the paper by Lindseth at al does not describe the diets used, it mentions “A variety of foods containing tryptophan were served, including mozzarella cheese, soy products, pumpkin seeds, and egg whites.” This implies that the variation of the tryptophan content of the two diets was manipulated by altering the protein levels in the diet. Therefore the high tryptophan diet would not have raised brain tryptophan and serotonin synthesis relative to the low tryptophan diet. 2. The authors did not consider what factors other than tryptophan might be responsible for the effects on mood that they report. Given that the low tryptophan diet provided <5 mg/kg body weight/d and the high tryptophan diet provided >10 mg/kg body weight/d presumably the protein content of the diet for the high tryptophan group was at least double that for the low tryptophan group. There is some evidence that protein has a greater satiating effect than the other macronutrients Pesta DH, 2014, so it is possible that the participants were more hungry on the low protein diet causing a lowering of mood. This could explain the better mood during the hight tryptophan diet phase. The researchers make no mention of measuring the hunger of the participants or possible preferences for the different diets. Furthermore, various amino acids are converted to psychoactive compounds including phenylalanine and tyrosine (catecholamines), methionine (S-adenosylmethionine), histidine (histamine) and leucine (glutamate), but the authors considered only the effect of tryptophan. 3. The section of the paper on Implications for Practice mentions that “the benefits of a diet for patients susceptible to affective disorders seem important since tryptophan-dense diets also improved mood and decreased symptoms of depression among depressed individuals in other studies (Badrasawi et al., 2013; Markus et al., 2008; Neumeister et al., 1998)”. The Badrasawi et al study Badrasawi MM, 2013 looked at the effect of a dietary supplement on mood. A comment on that article in PubMed (accessed by the previous link) explains why any effect on mood could not have been due to tryptophan. The Markus et al study Markus CR, 2008 looked at the acute effects of a high tryptophan hydrolyzed protein supplement on mood, and is therefore not relevant to how alterations in habitual food intake might alter mood. The Neumeister et al study Neumeister A, 1998 looked at the effect of acute tryptophan depletion (ATD) on mood in recovered depressed patients. Information on the ATD technique as used by Neumeister et al is available Young SN, 2013. In the control condition participants are given an amino acid mixture that is similar to the amino acid content of human milk, a source that is presumably optimum for human consumption. Because there are more LNAAs in this mixture than tryptophan, it will lower brain tryptophan slightly, but presumably within, or close to, the normal physiological range. The active treatment is the same as the control mixture except that tryptophan is omitted. The mixture induces protein synthesis and as tryptophan is incorporated into protein its level in blood and tissues falls dramatically, e.g. 80% or more decrease. This lowers brain tryptophan and serotonin synthesis greatly. In the Neumeister et al study ATD lowered mood relative to the control condition. However, the relevance of a lowering of mood caused by a large and unphysiological decrease in tryptophan, relative to control treatment that caused a small and probably physiologically relevant decline of tryptophan is not relevant to the possible effects of “tryptophan-dense diets”. Tryptophan in purified form is an antidepressant Shaw K, 2002 and under some circumstances tryptophan in purified form can improve mood in healthy people Young SN, 2013, Young SN, 2002. Markus et al Markus CR, 2008 and others have shown similar effects using proteins that contain unusually high amounts of tryptophan but are present in very small amounts in the diet, such as alpha-lactalbumin. However, as discussed above real foods will not raise brain tryptophan and serotonin even if the intake of tryptophan is elevated. Thus, the rationale for the study is not sound.


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    1. On 2015 Apr 27, Torgil Vangberg commented:

      We are working on making the script compatible with SPM12, and it will certainly be of interest to see if T1- and T2-weighted inputs will offer any further improvement in accuracy. Actually we did not expect much improvement using multi-spectral inputs since the T2 scans had 4 mm slices, but still it improved the agreement with manual tracing. The algorithm has also been tested with good results on a separate datasets that had 1mm isotropic T1- and T2-weighted images.


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    2. On 2015 Apr 15, Gerard Ridgway commented:

      It's interesting to see that multi-spectral data improves agreement with manual tracings (even though the tracing used only T1-weighted images). I think this is complementary to our work showing improvements in SPM12 over older versions (Malone IB, 2015), since SPM12 can also handle multi-spectral data. For example, considering the standard deviation of the differences with respect to manual, this paper's best (lowest) single-modality result is 41.64 mL for a method based on SPM8's New Segment toolbox. We obtained a value of 35.4 mL with SPM12. With T1- and T2-weighted data, this new paper obtains an impressively low 26.7 mL, also with lower mean difference (bias) than we found. It would be interesting to know whether SPM12 can further improve results using T1-weighted and T2-weighted data.


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    1. On 2015 Jul 13, CREBP Journal Club commented:

      This article offers an example of a high quality cohort study. Our discussion centred on grading the risk of bias of this study. We agreed that the risk of bias for this study was low; thus, the results can be considered valid. The findings also corroborate those reported in previous similar cohort studies.<sup>1</sup> This study provides an example of how to appropriately conduct a cohort study and we plan to use it as an example for teaching. The study findings could be used to inform the content of motivational messages to encourage smoking cessation. We noted that most of the participants started smoking in adolescence or early adulthood and we believed these age groups could be an ideal target for smoking cessation interventions.

      1.Doll R et al. Mortality in relation to smoking: 50 years’ observations on male British doctors. Br Med J. 2004; 328: 1519–28.


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    1. On 2016 Mar 07, Joe Newton commented:

      The axon connections (in space-time) limit the range of interactions between different regions. Also, the action potential conduction velocities, (in a space-time frame) are expected the major determinants of where-when they are summed i.e. integrated at downstream neurons. Conduction velocity has been hypothesized (Med Hypotheses. 1999 Jan;52(1):77-83) and the first postulate is being confirmed by large consortium studies for normal and multiple diagnostic anomalies. Example (Mol Psychiatry. 2016 Feb 9. Subcortical volumetric abnormalities in bipolar disorder. Hibar DP et. al.) The results are unusually interesting and support the 1999 space-time event network. Feedback, i.e. "reciprocal" connections, are, for simplicity, not illustrated in the 1999 hypothesis . Action potential events are physically expected to heavily influence the coordination of the simultaneous dynamic control system network events.

      Critique is important to us.

      Congratulations, Joe Ray Newton


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    1. On 2015 Jun 03, thomas samaras commented:

      A number of studies have shown shorter people have lower blood pressure, TG, insulin, and higher HDL. All these are related to lighter weight in addition to shorter height. In addition,lower mTOR and higher adiponectin are related to smaller body size and lower CHD/CVD. Thus, many biological parameters appear to favor shorter, lighter body builds in terms of lower risk for coronary artery disease.

      See entry by Samaras below for an explanation of why shorter people do not have a genetic tendency toward CHD but actually are inherently protected from CHD. When compared to tall people of the same body proportions, the biological advantages of shorter, lighter bodies include lower blood pressure, lower BMI, lower left ventricular mass, longer telomeres due to lower attrition, higher sex hormone binding globulin, greater heart pumping efficiency,lower pulse wave velocity, lower DNA damage, and lower work load.

      Several references that expand on the relation of smaller body size to lower CHD and greater longevity are given in my comment below.


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    2. On 2015 Apr 14, thomas samaras commented:

      I have studied the relationship between height, chronic diseases, and longevity for almost 40 years. One of my papers appeared in the Indian Heart Journal (2013) that summarized worldwide findings showing shorter people have inherently lower heart disease. In 2014, I had a paper published in the Journal of Scientific Research & Reports that summarized key findings showing shorter people live longer. If tall people had inherently better hearts, then why do today's taller Americans have more coronary heart disease (CHD) compared to the early 1900s when we were a few inches shorter? Also women are shorter than men and have less CHD.

      Studies from the 20th C found that many populations were free of CHD and stroke. Yet, these people ranged from less than 5 feet to about 5 feet, 4 inches. These populations included Solomon Islands, Papua New Guinea, Kalahari Bushmen and the Congo pygmies. I know of no modern population that is free of CHD.(Major food changes and increased height have occurred over the last few decades).

      In 2007, The World Cancer Research Fund reported that until recently, CHD was rare. However, in parallel with industrial development, we have seen increases in height, weight and chronic disease (which includes CHD).

      Of course, both tall and short people can reach advanced ages without CHD. Many other factors are involved, such as genetics, diet, exercise, smoking, weight in relation to height, income level, etc. I found that height represents about 10% of the total longevity picture.

      Unfortunately, when it comes to human health and mortality, conflicting studies abound. However, confidence in a study's findings should be based on support from different types of studies (e.g., ecological, longitudinal, cross-sectional) that provide consistent results and include populations from different parts of the world and different ethnic groups.

      I have reported scores of examples showing that non-Western shorter people have less CHD than taller Westerners. See www.humanbodysize.com for a listing of over 45 papers, book chapters and books expanding on what is discussed here. Some papers and a book related to height and CHD are listed below.

      Samaras TT. Shorter height is related to lower cardiovascular disease risk—A narrative review. Indian Heart Journal 2013; 65: 66-71.

      Samaras, TT. Is short height really a risk factor for coronary heart disease and stroke mortality? A review. Med Sci Monit 2004; 10(4): RA63-76.

      Samaras TT. Evidence from eight different types of studies showing that smaller body size is related to greater longevity. Journal of Scientific Research & Reports 2014: 3 (16): 2150-2160, 2014; article no. JSRR.2014.16.003.

      He Q, Morris BJ, Grove JS, Petrovitch H, Ross W, Masaki KH, et al. Shorter men live longer: Association of height with longevity and FOXO3 genotype in American men of Japanese ancestry. Plos ONE 9(5): e94385. doi:10.1371/journal.pone.0094385

      Samaras TT. Human Scaling and Body Mass Index. In: Samaras TT (ed): Human Body Size and the Laws of Scaling: Physiological Performance,Growth, Longevity and Ecological Ramifications. New York: Nova Science Pub; 2007: pp 17-32.

      Bartke A. Healthy Aging: Is smaller better?-A mini-review. Gerontology 2012; 58: 337-43.


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    1. On 2016 Aug 23, Ben Goldacre commented:

      This trial has the wrong trial registry ID associated with it on PubMed: both in the XML on PubMed, and in the originating journal article. The ID given is NCT01362107. We believe the correct ID, which we have found by hand searching, is NCT01368107.

      This comment is being posted as part of the OpenTrials.net project<sup>[1]</sup> , an open database threading together all publicly accessible documents and data on each trial, globally. In the course of creating the database, and matching documents and data sources about trials from different locations, we have identified various anomalies in datasets such as PubMed, and in published papers. Alongside documenting the prevalence of problems, we are also attempting to correct these errors and anomalies wherever possible, by feeding back to the originators. We have corrected this data in the OpenTrials.net database; we hope that this trial’s text and metadata can also be corrected at source, in PubMed and in the accompanying paper.

      Many thanks,

      Jessica Fleminger, Ben Goldacre*

      [1] Goldacre, B., Gray, J., 2016. OpenTrials: towards a collaborative open database of all available information on all clinical trials. Trials 17. doi:10.1186/s13063-016-1290-8 PMID: 27056367

      * Dr Ben Goldacre BA MA MSc MBBS MRCPsych<br> Senior Clinical Research Fellow<br> ben.goldacre@phc.ox.ac.uk<br> www.ebmDataLab.net<br> Centre for Evidence Based Medicine<br> Department of Primary Care Health Sciences<br> University of Oxford<br> Radcliffe Observatory Quarter<br> Woodstock Road<br> Oxford OX2 6GG


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    1. On 2015 May 02, David Keller commented:

      A question of publishing ethics: how much financial conflict of interest is too much?

      Authors are required to include a list of their financial conflicts of interest at the end of each publication in most medical journals today. The monetary value of such conflicts can range from minor (such as accepting a free meal valued at $100 from a pharmaceutical sales representative) to major investments or income streams. Obviously, the latter case is of greater concern to the reader than the former, yet no information is currently provided with each publication to quantify financial conflicts. The readers, therefore, cannot distinguish between trivial conflicts versus enormous life-altering ones.

      I request Dr. Caplan to provide his views on the following question: should authors be required to declare the dollar amount of each financial conflict of interest at the end of each publication, in order to help readers distinguish between trivial and major conflicts? I invite him to exercise his ethical judgement on the conflicts of interest I discussed in my comments on an article published last month, at the following link:

      http://www.ncbi.nlm.nih.gov/pubmed/25636998#cm25636998_10015

      with reference to the $82,000 conflict of one author. How much credibility is lost by a paper affected by a conflict of this amount?


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    1. On 2015 Apr 13, Joe Newton commented:

      Major depression diagnosis in the absence of preexisting biomarkers is uncertain and a dilemma of psychiatry. However, measurable biomarkers of intracranial volumes are suggested by the large genetic and imaging consortium studies. (Stein JL, et al. 2012 Nat Genet. Apr 15;44(5):552-61). Nevertheless your paper is unusually interesting in suggesting ECT induced hippocampal volumes.<br> I have wondered for decades about how ECT improves nervous system coordination in a broad spectrum of abnormal behavioral responses.<br> Best wishes, Joe Ray Newton


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    1. On 2016 Jun 16, thomas samaras commented:

      Low BMI may be a reflection of lower socioeconomic status, smoking, or poor nutrition in the developed world. However, low BMI is not a problem according to a recent study by Aune et al. (2016) that found the best BMI was 20-22 for long-term mortality of life long non-smokers. This study involved a review of 230 studies, 30 million participants, and almost 4 million deaths. In addition, many pre-western people have BMIs of 19-22 and have virtually no CHD or stroke. Examples include 20th C populations in the Solomon Islands, Papua New Guinea and Kitava. In addition, the Kalahari bushmen and Congo pymies had no CHD or stroke around the middle of the 20th C. All these people were short and had low BMIs by today's standards. When these people adopt a Western diet, their BMIs and heights increase along with CHD and other chronic diseases.


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    2. On 2015 Jun 12, thomas samaras commented:

      If we look at non-Western populations, they tend to have low BMS's compared to developed countries and also have very low CHD. In many cases, short, low weight populations have no evidence of CHD or stroke; e.g., Solomon Islanders, Papua New Guinea, Kalahari Bushmen, Congo Pygmies, Yanomami Indians, and Kitavan Islanders. Their low CHD was evident in the mid 20th C and subsequent changes in nutrition and lifestyle have affected their current health. Studies summarizing these and other findings are discussed in two papers below. A paper on the relation of smaller body size to longevity is also listed.

      Samaras TT. Shorter height is related to lower cardiovascular disease risk—A narrative review. Indian Heart Journal 2013; 65: 66-71.

      Samaras, TT. Is short height really a risk factor for coronary heart disease and stroke mortality? A review. Med Sci Monit 2004; 10(4): RA63-76.

      Samaras TT. Evidence from eight different types of studies showing that smaller body size is related to greater longevity. Journal of Scientific Research & Reports. 2014: 3 (16): 2150-2160, 2014; article no. JSRR.2014.16.003.


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    1. On 2016 Aug 23, Ben Goldacre commented:

      This trial has the wrong trial registry ID associated with it on PubMed: both in the XML on PubMed, and in the originating journal article. The ID given is NCT0038. We believe the correct ID, which we have found by hand searching, is NCT00380562.

      This comment is being posted as part of the OpenTrials.net project<sup>[1]</sup> , an open database threading together all publicly accessible documents and data on each trial, globally. In the course of creating the database, and matching documents and data sources about trials from different locations, we have identified various anomalies in datasets such as PubMed, and in published papers. Alongside documenting the prevalence of problems, we are also attempting to correct these errors and anomalies wherever possible, by feeding back to the originators. We have corrected this data in the OpenTrials.net database; we hope that this trial’s text and metadata can also be corrected at source, in PubMed and in the accompanying paper.

      Many thanks,

      Jessica Fleminger, Ben Goldacre*

      [1] Goldacre, B., Gray, J., 2016. OpenTrials: towards a collaborative open database of all available information on all clinical trials. Trials 17. doi:10.1186/s13063-016-1290-8 PMID: 27056367

      * Dr Ben Goldacre BA MA MSc MBBS MRCPsych<br> Senior Clinical Research Fellow<br> ben.goldacre@phc.ox.ac.uk<br> www.ebmDataLab.net<br> Centre for Evidence Based Medicine<br> Department of Primary Care Health Sciences<br> University of Oxford<br> Radcliffe Observatory Quarter<br> Woodstock Road<br> Oxford OX2 6GG


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    1. On 2016 Apr 26, Jean-Luc Margot commented:

      This article includes the following claims: 1) the timing of peak pollination in Ephedra foeminea coincides with the full moon in July, 2) the plant can detect the full moon through light or gravity, 3) the full-moon detection trait is an evolutionary adaptation that aids the navigation by pollinating insects.

      These extraordinary claims are made on the basis of 3 data points. There is no warning or acknowledgment about the possibility that the approximate coincidence between the 3 observed pollination peaks and the full moon could be entirely fortuitous. A chance alignment at the level observed by the authors is expected in about 0.5% of similarly constructed studies. Because the phenological record is extensive, it is straightforward to identify multiple instances of seemingly striking coincidences between plant development phases and the full moon. When a sufficiently long record is examined, however, the apparent association with the full moon reliably disappears. It is likely that additional observations of pollination in E. foeminea will invalidate the claims described in the article.

      The authors invoked the detection of lunar tides by E. foeminea as a possible mechanism for the observed coincidence. Because of the form of the gravity potential, the gravity signals at new moon and full moon are roughly equivalent, and one would not expect a gravity trigger at full moon that does not also act at new moon, when pollination peaks were not observed. In addition, the lunar tidal signal is about 50,000 times weaker than the tides raised by a botanist making observations in the field.

      The journal Biology Letters declined to publish a comment that describes the limitations of the data and interpretation and that proposes an alternate hypothesis (chance). This comment was later published in the Journal of Biological Rhythms (J. L. Margot 2015).

      Regrettably, a review article on the Gnetales (S. M. Ickert-Bond and S. S. Renner 2016) states the poorly supported claim of a lunar influence on E. foeminea as fact, without describing the limitations of the data and interpretation, and without mentioning the alternate hypothesis.


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    1. On 2015 Apr 02, Jacob H. Hanna commented:

      We have republished a corrected version of our JCI 2004 paper on bioRxiv: http://biorxiv.org/content/early/2015/03/30/016816

      We will not seek to republish it elsewhere in any peer-reviewed journal, as it has been 10-12 years since publication, and the study lacks any novelty at this point in time.


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    1. On 2016 Nov 22, DP Zhou commented:

      After patients spend all their savings for medicines not covered by health insurance, they extort the doctors and the hospitals as the last option to recover some cost of medicines. This is seen most often in cancer patients, who must pay cash to buy additional length of survival.

      The medical education in China was established in close collaboration with the United States, especially Rockefeller Foundation and Yale University (1). The medical professionalism was particularly stressed, and private practice of medical graduates were strongly discouraged by Yen Fuqing (2), the founder of Shanghai Medical College and first Minister of Public Health of Republic of China.

      1, Bridie andrews and Mary Brown Bullock. Medical transitions in twentieth-century china, 2014, Indiana University Press.

      2, Yimin Qian and Zhiyuan Yan. Yan Fuqing. 2007, Fudan University Press.


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    1. On 2015 Jul 22, NephJC - Nephrology Journal Club commented:

      This editorial, along with the entire special issue, was discussed on June 16 and 17 2015 in the open online nephrology journal club, #NephJC, on twitter. Introductory comments are available at the NephJC website.

      The discussion was scintillating with more than a 100 participants, including most of the authors. A transcript and a curated (i.e. Storified) version of the tweetchat are available from the NephJC website. Some of the themes (amongst many) discussed were

      • the role of work in social media and recognition (or lack thereof) in academia

      • social media as a path for continuing lifelong learning

      • the use of social media for research in medical education

      Interested individuals can track and join in the conversation by following @NephJC or #NephJC, or visit the webpage at NephJC.com.


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    1. On 2015 Jun 01, UFRJ Neurobiology and Reproducibility Journal Club commented:

      Although the findings of the study are interesting, we would like to point out that, due to differences in the interpretation of the term “spontaneous recovery”, the comparison between these results and previous results from the literature (Monfils et al., 2009, Clem et al., 2010) performed by the authors is not warranted. Spontaneous recovery is an intrinsic characteristic of the extinction process, and has been defined as a recovery of responding to the conditioned stimulus with the passage of time following the conclusion of extinction. (Bouton et al., 2002). However, one should observe that, since the decay of fear within an extinction session involves different mechanisms than those involved in extinction from one session to the next (Plendl & Wotjak, 2010, Almeida-Corrêa et al., 2015), a difference between the end of an extinction session and the beginning of the next test session is actually to be expected, and does not constitute evidence of spontaneous recovery, as the freezing epochs are not comparable (Plendl & Wotjak, 2010). Thus, the adequate way to evaluate spontaneous recovery is to compare freezing between two test sessions of similar duration, spaced apart and happening after the extinction session (such as in Monfils et al., 2009 and Flavell et al. 2011). Furthermore, it is worth highlighting that the training-test interval in this article and in the ones cited in Table 1 are clearly not the same. In Monfils et al., 2009 and Clem et al., 2010, the return of fear is prevented in the retrieval-extinction group 1 month and 1 week after extinction, respectively, but neither show a return of fear 24h after the extinction session. Chan et al. 2010 also don’t see a return of fear in either experimental group when they are tested in the extinction context, while in Stafford et al. 2013, freezing during the extinction session is not shown. Thus, rather than contradicting the previous findings, as discussed by the authors, the current results actually confirm those of Monfils et al. (2009) and others – namely, that a retrieval session before extinction does not alter freezing in a session 24 h later. It is surprising that the authors discuss many variables that might have influenced the “contradictory” results between this and the abovementioned papers, but don’t consider the different definitions of spontaneous recovery and the different delays between extinction and testing used in the articles. To clear up these misunderstandings in future studies, we propose, as others have done (Plendl & Wotjak, 2010), that the term “spontaneous recovery”, irrespectively of the time interval, should be based on comparisons between test sessions of similar duration happening after extinction, which is not the case when the end of a long extinction session is compared to a short test session. As has been discussed in Riebe et al 2012, the increasing number in studies being published in fear extinction don’t follow harmonic experimental designs, nomenclature or data analysis, therefore making it difficult to compare studies among themselves. The newly explored sub-field of post-retrieval extinction seems to be repeating this pattern, and we would like to reinforce the importance of avoiding such repetition.


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    1. On 2017 Mar 05, thomas samaras commented:

      This results of this study are consistent with a similar study by Elsayed, et al. This study is also consistent with many longevity and mortality studies published over the last 40 years. For example, a short list is presented next.

      He, et al. Japanese-Hawaiian: shorter elderly have lower mortality and live longer Chmeilewski: Based on 800,000 deceased Polish men and women, shorter people live longer Samaras: Eight difference types of studies support the greater longevity of smaller people Samaras: shorter men lived longer based on a study of deceased San Diego veterans Mueller: shorter elderly West Point graduates had a lower mortality after 60 years of age Salaris: shorter deceased men in Sardinia lived longer Miller: shorter men and women who died in Ohio lived longer Willcox: short Okinawans have highest percentage of centenarians Wilhelmsen: men who were shorter at 67 years of age were more likely to reach 90 years of age Bartke: smaller body size promotes greater longevity


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    1. On 2016 Aug 14, Leigh Jackson commented:

      A very good overview. My personal conclusion:

      Consistent results of systematic reviews show that acupuncture is no better than sham for acute/subacute LBP, either for short term pain relief or functional improvement.

      Conflicting results of systematic reviews mean it is unclear whether acupuncture is effective for short term pain relief for chronic LBP; however, consistent results show no functional benefit.


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    1. On 2016 Jun 20, Darya Vanichkina commented:

      UCSC genome browser in-silico PCR on hg19 UCSC genes predicts that a different lincRNA (on a different chromosome; chr10:102,133,333-102,148,116 vs chr21) will be amplified using the primers reported to target linc00320. How was this off-target PCR controlled for? Was the PCR product sequenced to confirm correct template was being amplified?

      >uc001kra.4__LINC00263:555+727 173bp GACTCCTTTGGGAGACCAGTG AGGTCACAGGGGATTTGATGG GACTCCTTTGGGAGACCAGTGccctgttgtcgccctcactccgtgaggag atccacctatgatctcaggtcctcagaccaaccagcccaaggaacatctt gccaatttcaaatcggaagataggagtgtcaggcctctgagtccaagcta agCCATCAAATCCCCTGTGACCT

      >uc001kqz.4__LINC00263:555+724 170bp GACTCCTTTGGGAGACCAGTG AGGTCACAGGGGATTTGATGG GACTCCTTTGGGAGACCAGTGccctgttgtcgccctcactccgtgaggag atccacctatgatctcaggtcctcagaccaaccagcccaaggaacatctt gccaatttcaaatcggataggagtgtcaggcctctgagtccaagctaagC CATCAAATCCCCTGTGACCT


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    1. On 2015 Jun 02, Thomas Perls, MD, MPH commented:

      An important conclusion of this work is that the genetic basis of surviving to age 90 years (the 5th and 15th percentiles of survival for men and women belonging to the 1900 birth cohort) is weaker and different from the genetic basis of surviving to the top one percentile, which in turn is different for those surviving to the top 0.1 percentile of survival.

      The authors of a meta-analysis of largely nonagenarians (Deelen J, 2014) indicate that they were unable to reproduce the associations of the 281 SNPs in Sebastiani P, 2012 and used their negative result to assert that the findings were false positive associations. However, what this analysis of sibling relative risk of extreme longevity (Sebastiani P, 2016) indicates is that one should not be surprised by the lack of consistent results between these studies of people surviving to markedly different percentiles of survival and therefore having substantially different degrees of statistical power to discover variants associated with extreme survival. Reinforcing this point, when studies are similar in terms of a rare percentile of survival, a large number of the associated SNPs are actually replicated (Sebastiani P, 2013).


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    1. On 2015 Mar 27, Peter Hajek commented:

      This is a highly misleading conclusion from studies with little relevance for human health. There are clear data from long-term NRT use and population data from users of snus which show that long-term use of nicotine itself, outside pregnancy, carries minimal or no health risks. (There are also data that showing nicotine use prevents Parkinson's disease and lowers BMI, and in smokers switching to alternative nicotine delivery systems, it alleviates a host of negative effects). It makes no sense to demand that nicotine products with minimal or no health risk which can benefit smokers greatly are sold under medical supervision while tobacco products are purchased freely. Such demands just serve to protect tobacco sales.


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    1. On 2015 Jun 05, BSH Cancer Screening, Help-Seeking and Prevention Journal Club commented:

      This article was selected for the HBRC journal club held on June 2nd, 2015. The topic of ‘don’t know responses’ in perceived risk items is of particular relevance to our group and raised several useful discussion points. We thank the authors for taking this work forward, and encourage further study in the area.

      The general consensus of the journal club was that the use of two samples was a strength of the research. However, we noted differences in the availability of perceived risk items, the use of different predictors between the datasets, and perhaps most importantly, the availability of explicit ‘don’t know’ response options in one survey but not the other. This made comparisons between the samples and interpretation of the findings difficult. The authors should be credited with making use of available data, but it seems clear that their interesting findings warrant further investigation using study designs that explicitly set out to investigate this phenomenon. Following this, the journal club discussed the research team’s recent research endeavours in this area, presented at the Society of Behavioral Medicine Conference.1

      Conversation turned to the meaning of a ‘don’t know’ response. We felt this was important because observational studies do not allow us to disentangle true ‘don’t know’ responses from those who lack the motivation to complete all survey items. Hay and colleagues addressed this limitation by excluding participants with multiple ‘don’t know’ responses elsewhere in the questionnaire; a decision we agreed with. Suggestions for future research investigating the meaning of a ‘don’t know’ response included using semi-structured interviews purposively sampling participants who selected a ‘don’t know’ response, or verbal protocol (think-aloud) studies encouraging subjects to vocalize their thoughts when completing perceived risk items. While these methods have limitations of their own, the consensus was that they would be worthwhile approaches. We also recommend that future research should include a range of perceived risk items, including ‘feelings of vulnerability’ also known as ‘risk as feelings’; an item not available to Hay and colleagues.

      In sum, the HBRC journal club enjoyed reading this article, and encourages others to take note of their findings. These data have clear implications for scientists who use survey methodology, as well as those making policy level decisions based on their findings.

      References

      1. Kiviniemi M. T., Ellis E. M., Orom H, Waters E. A., Hay J. (2015) Providing a “don’t know” response option changes population perceived risk estimates. Annals of Behavioral Medicine. 49 (Suppl1): S1-S258, C120


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    1. On 2016 Jan 29, Martin Pusic commented:

      Thank you for this insightful review - we're glad that the article created such a rich discussion. Here are a couple of other thoughts:

      . "different tracks for different learners" - what a learning curve makes manifest is the time component of an assessment. As a medical educators, we have the privilege of teaching highly motivated learners who almost always get over whatever bar we set for them. If we grade ourselves as teachers by counting how many learners get over the bar, it is easy to perceive ourselves as successful; however, if instead we grade ourselves on the SLOPE of the learning curve, now we have a metric that challenges us to grade our efforts in terms of learning efficiency, which is amount of learning per unit of learning effort expended. This does three good things: 1) it orients us towards maximizing the most precious student commodity - time; 2) it prompts educators to consider more closely the PROCESS of learning as that's how you improve the slope and 3) it allows us to use the variability in paths/slopes to learn the best ways of teaching and learning. So it may be that we do not need customized learner development charts, as well as those work for pediatrics, but rather to learn from those outliers who fall away from the average curve so as to feed that back into the system to improve the learning for everyone.

      .in the "life-cycle of clinical education" we would also encourage you consider the asymptote. The asymptote defines the "potential" of a learning system. "How good can we possibly be, if we used this system an infinite number of times?" Improving the slope means we get people up to competence more efficiently. Improving the asymptote means we get even better competence. In some cases we only need "x" amount of minimum competence and we're fine (think hand washing); but in most areas of medicine, we can always do better. The path to competence is all-important, but our learning systems would do well to also map out the path from competence to excellence, defined as being the very best any of us can be. The asymptote, along with the very shallow slope of the learning curve as it approaches it, gives us an idea of what excellence takes.


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    2. On 2016 Jan 28, Clinton K Pong commented:

      Journal club review from a conference for Educators in Health Professions:

      Pusic et al present a useful argument for the development and application of Learning Curves in Clinical Education. The learning curve graphs a mathematically modelled relationship between effort and competence. The authors suggest applications to practice citing work in radiological interpretation learning and the limitations of the work to date. At our journal club, we further considered learning curve application in the life-cycle of clinical education.

      Theme 1: Undergraduate Education - the Steep Learning Curve of Med Ed

      Learning curves may follow & identify the learner throughout their learning from undergraduate time onwards. Early engagement with validated learning curves, if available, across multiple domains, may have the potential to inform the learner and assist in his/her application to education early in their career. Learning curves may become a useful tool in assisting the learner-in-difficulty but challenges us to consider if there is long-term benefit of remediation in medical training.

      Theme 2: Graduate Professional Training - Trainees falling off the "Growth Chart"

      We considered how generalizable learning curves would be in the specialties where complex communication/perception is the competence required – eg the learning of elderly medicine rather than the more measurable accuracy/time-taken per task.

      Does deliberate observation of practice confound performance in learning curves versus real-time learning in the clinically chaotic environment?

      The evidence presented (Fig 7) suggested to us that a competency-based curriculum could result in different tracks for different learners – would it be ethical to continue with a time-based curriculum with the cost implications thereof if the majority of learners reach competency in a shorter than prescribed time or the corollary. Are there opportunity costs in overtraining the accelerated learner? How would programs and health systems respond/accommodate and support the learners who requires more/less than standard time to complete?

      The curve may have a greater relevance in self-assessment metrics than formal assessment. Its creation informs reflective practice/analysis/germane learning and ideally would be used early in the training cycle. There may be risk in adding to the burden of extraneous cognitive load if performance anxiety mitigates the safety of the learning environment.

      The authors acknowledge that there is variation in the starting point and slope of the learning curve that mostly cannot be controlled. In time, there may be evidence to describe if a less steep slope implies a perpetual shift in the curve to the right compared to peers or whether performance may suddenly shift the curve to the mode or even to the left as learning breakthroughs occur? The cohort is too small to usefully study these variations in this domain of learning.

      Prediction models would be useful especially if wider work supports wide variations in trajectories of learning in complex clinical tasks.

      What is happening in the area under the curve above the standard competence – Do these learners use and practice transferable skills that keep them ahead on the next learning curve?

      Should we have customised learner development charts in multiple domains from the analogy of paediatric development milestones or growth curves – correction for some confounding factors could be achieved by customisation – for example - gender, age, ethnicity, population of reference – could these be used in clinical education to generate ‘growth of learner performance’ curves. Sub-analysis may lead to greater understanding of the non-thriving learners - the “under effort for time” learner versus the “under performance for effort” learner in the analogy of the skinny child versus the stunted child!

      Theme 3: Faculty Development - "Cultivating Deliberate Expertise"

      We considered how learning curve analysis could inform medical registration policy for re-certification if the decay curves were further developed. The unit time for performance degradation may not be identical in each cycle for revision learners. The theory of spacing learning activity to afford deeper learning over time may contribute to determining the appropriate cycle time.


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    1. On 2015 Oct 21, Chetna Malhotra commented:

      Thank you for your interest in the paper. You may also be interested in another paper from our team, using the same DCE, published in Health Policy (2015) comparing patient preferences with those of older adults in the community. A forthcoming manuscript by our team in BMC Palliative Care also uses a similar methodology to assess variation in physician recommendations for end-of-life care.

      The attributes for the DCE used in this manuscript were based on a review of literature as well as results from our own focus groups with older Singaporeans (Malhotra et al, 2012), thus enabling us to tailor the DCE to our local context. Due to space considerations, we were unable to present the regression table in the paper, but the rescaled regression coefficients are shown in figure 1 of the manuscript. The figure allows for easy interpretation of the regression results. The DCE experimental design was a main effects design and thus limited any post hoc testing for interactions. This could be an area of future research. Ethical considerations limited our ability to recruit patients who were not aware of their own diagnosis. This would be a common consideration for all palliative care researchers working in similar settings.


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    2. On 2015 Oct 13, Cicely Saunders Institute Journal Club commented:

      This paper was discussed at a Journal Club at the Cicely Saunders Institute, King's College London, on Wednesday 7th October 2015.

      This study is a nice example of how a discrete choice experiment (DCE) can be used in palliative and end-of-life care to assess preferences for aspects of care. It also raises some very interesting questions about the differences in priorities and the extent to which caregivers might be able to act as a proxy for patients, an important consideration for end-of life care. Our Journal Club discussed the work required to ensure sufficient attribute identification for a robust DCE, and wondered if the attributes decided upon in this paper sufficiently captured what is most meaningful for patients and caregivers at the end of life, i.e., there was no mention of a systematic review used to develop the attributes (see Bridges et al., 2011 for an example of DCE reporting guidelines). We also would have liked to see a table of the probit regression output for clarity on how the willingness-to-pay was calculated, and more detail on this in the methods. Furthermore, we found it confusing that the authors state in the discussion that their sample size was too small to explore interaction effects, while it appears they recruited 70% more than their minimum acceptable sample size – some explanation would have been helpful. Lastly, we wondered about the potential risk of bias of only including those patients who knew their diagnosis. This may limit the generalisability of the findings, even to a Singapore context. We enjoyed discussing this paper, and look forward to more papers using DCE methodology in palliative and end-of-life care.

      Commentary by Melinda Smith


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    1. On 2015 Apr 02, M Mangan commented:

      With florid rhetoric in the discussion, this paper far over-reaches what the actual research accomplished. In the work, researchers dumped a variety of solutions on bacteria, and found bacteria opened some channel proteins to deal with it. This is a very non-specific response to anything bacteria might encounter, such as even a change of pH or some membrane-impacting detergents or altered salinity. Appropriate controls--such as just the active ingredients they claim in the title--were not done. Nor were controls for surfactants. The work does not support the wild claims that have resulted.


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    1. On 2015 Jun 12, Philippe Terrier commented:

      There is a very unlikely result in table 3: the authors report regression result for the dependent variable CBMS: 1.000 x APStdDev - 1.000 x MLRange, R<sup>2</sup> =1.000 . This is a perfect prediction, which is impossible given the variability reported in table 1. Moreover, mean APSstDev is 1.3 (table 1) and mean MLRange is 7.3, in parallel, the mean CBMS score was 46 (p. 810, 3.2): applying the regression equation give 1.3-7.3=46 ! Maybe I do not understand the methodology, but that must be clarified.


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    1. On 2015 Sep 16, Geriatric Medicine Journal Club commented:

      We have so many guidelines with indications for when to start medications. Very few guidelines help the clinician assess when and how to stop medications. This article was critically appraised at the July 2015 Geriatric Medicine Journal Club (follow #GeriMedJC on Twitter). It was a lively discussion and the full transcript can be found at: http://embed.symplur.com/twitter/transcript?hashtag=GeriMedJC&fdate=07/31/2015&shour=00&smin=00&tdate=08/01/2015&thour=00&tmin=00 This pragmatic trial shows promise for conducting much needed deprescribing studies for other medications at end of life.


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    1. On 2016 Jun 21, Lydia Maniatis commented:

      The trick in science is to ask good questions, but that's more difficult than asking nonsense questions. Both types of questions can generate data, but only the former will, in some cases at least, produce data that is intelligible. The question and data here clearly fall into the latter category.

      The question being asked is how confident observers will be if we ask them to judge some aspect of a stimulus presented for only 200 milliseconds, and how will this judgment of confidence change when we vary the frequency distribution of some aspect of the display. (The logic of varying frequencies in this way is related to a never-really-explained and huge and falsifiable assumption that a. signal detection theory is appropriate for modelling perceptual processes and b. that varying the distribution of some experimental display is equivalent to the noise term in this SDT paradigm.)

      Why 200 milliseconds? Why were observers encouraged to respond quickly? Why do we care how observers feel (or at least respond when forced to express a feeling) about their performance in such extremely pinched and unnatural circumstances?

      As it happens, the authors found no consistency between individuals (apparently each person has some preference for responding, but so what?) and no consistency between this study and other studies with the same focus.

      The authors provide no justification for why they chose the particular task and the particular experimental parameters they did. What if they had used a different task? What if they had let observers see the stimulus for 500 milliseconds, or even an entire second? Would there be reason to expect different results? Why the forced choice? If you're really interested in confidence, then forcing observers to respond even if they have no real preference will just produce a false impression of confidence, a response based on some rule of thumb that doesn't necessarily measure confidence. You lose precisely the information that you're supposed to be interested in.

      The number of possible studies along these lines, using arbitrary tasks and arbitrary parameters, is infinite. Each one will certainly produce some result, and the results will just as certainly be widely variable and often mutually inconsistent. "Visual confidence" is a data mill in need of a rationale adequate to guide experimental control of variables, so that the results of different experiments can be compared with more confidence than the hopelessly vague speculation on display here:

      "In any case, the reasons why these inter-individual differences occurred in our study, but not in other studies (e.g. [9, 13]), remain to be clarified, but the stimuli or the procedure (e.g. the use of confidence ratings vs. confidence comparison) might have played a role in this issue. One could speculate that these inter-individual differences relate to the prior beliefs about the noise variance, or to the sensory sensitivity to motion variability or motion deviations. It is also possible that they relate to more cognitive phenomena like misperception of statistical variability ([20]), distortions in subjective probability weighting ([21]), or attitudes towards risk. In any case, past research has demonstrated that such individual differences do provide an interesting leverage when investigating choice behavior and metacognitive abilities, both from a behavioral and a neuroscientific perspective (e.g. [22㲴])."

      Could be anything; the pitfalls of theory-lite data collection.

      Throwing out three out of the 18 original participants based on "poor performance" or "extreme bias" in the confidence task is questionable methodologically and seems like a way to paper over the lack of robustness and consistency (and intelligibility) in the results of a task whose difficulty is of the nature of testing, e.g., figure-ground perception in a myope without their glasses. Adding theoretically trivial difficulty of this type makes the data fuzzy and allows flexibility and perpetual readjustment in their interpretation, and perpetual pretexts for more data collection.

      With respect to the idea that individual diffs might "relate to the prior beliefs about the noise variance":

      Not only is variance treated as "noise" in the signal detection scheme, but now we layer on top of this tenuous assumption another one, that the perceptual (or cognitive?) system might have prior beliefs about this variance/noise. Note that the experimenter-determined variance is never expressed in the stimulus as such. The stimuli experienced could be from any distribution that simply contains each sample experienced. How would we determine which distribution conforms to the supposed prior belief? If there is no way to determine this, then the possibility is not testable, and thus not scientific.


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    1. On 2015 Mar 24, Jorge H Ramírez commented:

      This abstract does not comply with the extension to the CONSORT statement: http://www.consort-statement.org/extensions?ContentWidgetId=562

      I am particularly concerned with the registration of this trial:

      The registration number should appear in this abstract according to the CONSORT Statement.

      I cannot confirm if the registration number appears in the full text of this manuscript because it's behind a paywall (i.e., not an open-access article).

      No results for the search query "duloxetine carnitine" were retrieved by ClinicalTrials.gov and WHO ICTRP (search date: March 24, 2015).

      A significant number of registered duloxetine trials remain unpublished despite being completed several years ago.(1)

      References

      1. Ramirez, Jorge H (2014): Duloxetine database | WHO ICTRP, ClinicalTrials.gov, Embase, PubMed, ISI, others. figshare. http://dx.doi.org/10.6084/m9.figshare.1096304


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    1. On 2015 Apr 01, Mario Capasso commented:

      The authors of this meta-analysis have reported into the manuscript this sentence: "the study performed by Capasso et al Nat Genet 2009 evaluating the association between BARD1 Arg378Ser polymorphism and neuroblastoma susceptibility reported the completely opposite result compared to the study performed Capasso et al Carcinogenesis 2013. We read these two papers carefully and didn’t find the interpretation about this phenomenon by the author." This is clearly wrong. Indeed, in the two papers, we reported the frequency of the minor allele (MAF) which in the American population is G, and in the Italian population is C. In both populations, the disease associated, or risk, allele is G, with a frequency of 0.51 and 0.42 in American cases and controls, and of 0.65 and 0.52 in Italian cases and controls. Therefore, while the minor allele is different, there is no difference in the neuroblastoma risk allele, and the results are consistent in the two populations.


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    1. On 2015 Nov 18, David Keller commented:

      One DaTscan exposes basal ganglia to an ionizing radiation dose equal to 21 CT scans, for what benefit?

      According to the DaTscan product information, this radio-pharmaceutical exposes the basal ganglia to 42.5 mSv of ionizing radiation, equivalent to having 21 brain CT scans [1], a level of radiation exposure with unknown effects on the already injured neurons of the substantia nigra (SN). Indeed, no clinical study has assessed the possible worsening of Parkinson's disease caused by a DaTscan, by means of accelerated death of SN neurons due to radiation exposure.

      The gold standard used in this study is clinical diagnosis, which causes zero radiation exposure to the SN, and a significantly more sensitive and specific diagnostic yield. Why, then, should any clinician order a DaTscan, at least until we know the effects of 42.5 mSv of ionizing radiation on the sick SN neurons of a Parkinson's patient?

      Reference:

      1: Keller DL. Proposal for a clinical trial to test the safety of a widely-used radionuclide scan. Comment on PMID: 26236969. In: PubMed Commons [Internet]. 2015 Sept 15 [cited 2015 Nov 20]. Available from http://www.ncbi.nlm.nih.gov/pubmed/26236969#cm26236969_11818


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    1. On 2015 Sep 16, Geriatric Medicine Journal Club commented:

      The related study (Delayed-start analysis: Mild Alzheimer's disease patients in solanezumab trials, 3.5 years. Alzheimer's & Dementia: Translational Research & Clinical Interventions. In press. 2015) was critically appraised at the August 2015 Geriatric Medicine Journal Club (follow #GeriMedJC on Twitter). The full discussion can be found at: http://gerimedjc.blogspot.com/2015/09/study-author-joins-us-for-successful.html?spref=tw This is an interesting study design, but the hype around the results may be disproportionate or premature to the magnitude of clinically meaningful benefit shown.


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    1. On 2016 Jun 01, Kenneth Witwer commented:

      It is reported that "miR-150 mRNA and protein expression levels" were assayed in this study, but miR-150, a 22-nucleotide RNA, is neither a messenger RNA nor a protein. The reverse transcription and RT-PCR steps described in the methods could not have amplified a microRNA specifically. Furthermore, both Western blots and immunohistochemistry images are shown and said to have been obtained with a "mouse polyclonal anti-miR-150 antibody." The target is repeatedly referred to as a protein, reducing the likelihood that typographical errors or translation issues interfered with reporting. Additional methodologic details would be helpful in resolving these problems, including primer sequences and the actual protein target and source of the antibody.


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    1. On 2015 Apr 22, Thomas Heston commented:

      Compared with the functional testing group, those undergoing an initial CT angiogram were 50% more likely to undergo catheterization (12.2% vs 8.1%) and almost twice as likely to undergo revascularization (6.2% vs 3.2%). These additional procedures, however, did not show any clinical benefit during a median follow-up period of 25 months, as measured by the primary outcome measure (3.3% in the CTA group vs 3.0% in the functional testing group). Thus, the obvious conclusion seems to be that CTA results in more radiation, more catheterizations, and more revascularizations --- without any improvement in clinical outcomes. The results from this study suggest that functional testing is the best initial noninvasive test in symptomatic patients with suspected coronary artery disease.


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    1. On 2015 Sep 16, Geriatric Medicine Journal Club commented:

      This study aims to look at a multicomponent intervention to prevent cognitive decline in at-risk elderly. This article was critically appraised at the July 2015 Geriatric Medicine Journal Club (follow #GeriMedJC on Twitter). The full discussion can be found at: http://embed.symplur.com/twitter/transcript?hashtag=GeriMedJC&fdate=07/31/2015&shour=00&smin=00&tdate=08/01/2015&thour=00&tmin=00


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    1. On 2016 Apr 25, Johannes M Dijkstra commented:

      The title of this article "CXCR3 chemokine receptor enables local CD8(+) T cell migration" is not substantiated by the experimental data, because increased presence of the CD8(+) T cells in the infected cell area may be explained by increased binding.

      Although not immediately clear to readers, the article is mostly about a time window effect at days 5-7 after infection. Important observations for the virus titers on those days should be shown if Fig. 3F, in which the data for the day 5 p.i. result are contradictory to the story. That figure is either an error, or needs serious discussion.

      Previously, I have posted these comments plus a few additional minor ones on the Immunity site below the article, but the authors did not respond, and Immunity made the comments close to invisible. Then I placed my comments as a correspondence article on F1000Research, where the advantage is that independent third parties can have their say as reviewers. For more explanation of the above points, please see that web-site http://f1000research.com/articles/4-922/v1 .

      However, the F1000Research system requires two reviewers before the publication can proceed, and I only managed to find one reviewer within the relevant research field. The one reviewer, Dr. J.R. Groom, as I interpret her words, agreed with me that Fig. 3F requires an explanation by the authors, but feels that the text by Hickman et al. on the migration versus binding issue is more nuanced than I portray it in my criticism. Her comments can be read in detail at http://f1000research.com/articles/4-922/v1 . Although I do agree with her that within the Hickman et al. text some nuances can be found, that does not take away that they boldly and in my opinion without substantiation concluded a migration enabling effect in the title and that most readers will understand the wordings by Hickman et al. similar to as reflected in Fig. 1 of the corresponding preview article by Beura and Masopust http://www.cell.com/immunity/fulltext/S1074-7613(15)00095-3 .

      Both Dr. Groom and I agree that the technical part of the experiments in the Hickman et al. article is mostly sound.


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    1. On 2015 May 15, M Felix Freshwater commented:

      Although not called a systematic review, in fact it was one for two obvious reasons: 1. Systematic reviews are defined by Cochrane as analyses of articles with “a clearly stated set of objectives with pre-defined eligibility criteria for studies”. The authors’ stated objective was “to identify the most highly cited microsurgery articles”, and the authors’ pre-defined eligibility criteria included articles that appeared in five high-impact peer-reviewed journals. 2. It was assigned a Level of evidence III. Using the ASPS level of evidence system a level III is a systematic review of retrospective cohort or comparative study; case-control studies; or while according to 2009 OCEBM level 3 is a systematic review of case control studies.<br />This review does not meet the minimum standards on how a proper systematic review should be reported that were codified in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and published in 2009.<br> Item 10 of PRISMA’s checklist describes the proper methodology for validating extracted data: “Describe … any processes for … confirming data from investigators.” The authors did not describe how they confirmed that their data extraction was accurate. AMSTAR, a validated checklist for measuring the quality of systematic reviews states: “There should be at least two independent data extractors and a consensus procedure for disagreements should be in place.” This review contains erroneous data, which may be a result of not reading the original papers and/or of not complying with PRISMA. One obvious example is the misidentification of the country of origin of the most highly cited clinical article. While the review stated that the country of origin was the United Kingdom, the paper itself never uses the phrase “United Kingdom” and clearly identifies its country of origin as Australia on its first and final pages. As this review deemed it worthy to analyze papers by country, any results and conclusions based upon country of origin are suspect. Without duplicating the study, it is impossible for any reader to know which other data in this review are flawed. This review provides an educational opportunity, as it affords the editors and peer reviewers to join other journals that publish papers on microsurgery including Annals of Plastic Surgery, Journal of Plastic, Reconstructive & Aesthetic Surgery, Journal of Hand Surgery (Am) and Journal of Hand Surgery (Euro), which have adopted PRISMA as a requirement when reporting systematic reviews. I suggest that the editor, who also is a co-author of this paper, enforce the use of PRISMA in order to lessen the possibility of future errors arising from inaccurate data extraction.


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    1. On 2017 Mar 03, Matthew Speir commented:

      To add on to what Kim Pruitt said in her comment, our previous "RefSeq Genes" track was not equivalent to what was provided by RefSeq. It was based on the realignment of their provided RNAs to the genome.

      However, we recently released an "NCBI RefSeq" track that is based entirely on coordinates and alignments provided by the RefSeq group. You can read about it more on our website: https://genome.ucsc.edu/goldenPath/newsarch.html#030317.


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    2. On 2015 Mar 18, Kim D Pruitt commented:

      As the head of NCBI’s RefSeq project I would like to make a clarification on the relevance of the authors' results to RefSeq. The authors refer to the RefSeq dataset and UCSC RefGene dataset as if they are equivalent. However, the RefGene data represents annotation derived from UCSC-generated alignments of approximately 1/3 of the RefSeq data. The analysis presented here is of the UCSC RefGene dataset and not the complete RefSeq set as obtained at NCBI which builds and curates RefSeq. NCBI also provides human genome annotation data that includes the comprehensive RefSeq transcript data set. Details about the annotated location of a given RefSeq transcript at NCBI may differ from that shown in the UCSC RefGene track.

      Therefore, the relevance of this analysis to RefSeq is unclear.


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    1. On 2015 Mar 18, Markus Meissner commented:

      This is a very nice review by Boucher and Bosch, summarising our current knowledge of apicomplexan invasion pathways. In the first part of the review the authors focus on novel structural data of the individual complexes known to be involved in gliding motility and invasion, while in the second part the current data regarding potential, alternative invasion pathways are presented. While the authors favour the more “traditional” linear motor system, data from diverse groups have been openly discussed, although some of the arguments might need further clarification. For example, the authors do not mention one important feature of the GAP45-depleted parasites. In these parasites the integrity of the IMC is lost AND other motor components dissociate and mislocalise to the cytosol of the parasite. Yet, these parasites are still capable of moving and invading, although the anchorage for the motor complex is missing. In case of act1KO it is in our opinion unlikely that parasites still have sufficient actin for gliding motility and invasion yet not for egress or apicoplast replication. Furthermore, the controversy regarding the effect of CytoD on host or parasite actin (see Rynig and Remington, 1978; Dobrowolski et al., 1996; Gonzales et al., 2009) and recent data on the role of aldolase ( Shen et al., 2014 ) seriously undermine the original rationale for the linear motor model, and in our view suggest that the earlier data supporting the model should be treated with as much scrutiny as the recent data arguing against it.<br> I agree with the authors that findings in Toxoplasma cannot necessarily be directly transferred to Plasmodium. However, this is also the case for other apicomplexans, which have undoubtly different (or alternative) invasion mechanisms, such as Theileria or Cryptosporidium. Of note, Theileria has a well conserved AMA1, but doesn't form a tight junction. While Theileria might use AMA1 for “zippering” into the host cell, it doesn’t use it for force transmission, since invasion is independent of host AND parasite actin (Shaw, 1999). More experiments are required to make sense out of these sometimes conflicting data, which can at this point be interpreted in multiple ways, and we fully agree with the authors that we need an open, unbiased discussion in order to solve the puzzle.


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    1. On 2016 Jun 03, Lydia Maniatis commented:

      The authors of this article perform a useful service: They experimentally falsify a claim that currently enjoys some favor. Falsifying (false) assumptions is a fundamental activity in science; a science incapable of rejecting false views is incapable of selecting true(er) ones, and thus incapable of progress.

      This simple fact is so antithetical to the current “don't criticize” ethos in vision science that the authors have (either by choice or editorial demand) been forced to bury the lead and accentuate the mildly positive and/or vague. Thus the title of the article is vague, implying nothing and the abstract reports a mixed salad of findings. For a statement of any conclusions we're directed to the article itself.

      From the intro, we learn that Christou and Koenderink (1997) have speculated that the presence of smooth occlusions is a key factor in seeing “shape-from-shading.” Amazingly, in the nearly 20 years since, no one – including its originators - has actually tested this claim. After explaining what a “reasonable” suggestion this is, Todd and Egan note that “virtually all past studies have included visible smooth contours.” So they propose to put this suggestion to a real test, but aren't allowed to state it this strongly so near the beginning of the article; they are merely going to “further examine” the issue.

      The discussion also drags its feet in getting to the point, since the first thing we learn is that “One of the basic findings of the present investigation is that observers’ perceptions of 3-D shape from shading are sheared slightly toward the direction of illumination. This phenomenon was first discovered by Koenderink et al. (1996a, 1996b) and Christou and Koenderink (1997).” (The “phenomenon” is context-specific, since perceptions of 3D shape will certainly not always be sheared in the direction of illumination – it will depend on the shapes. All that can be said is that this sometimes happens).

      Finally, we get to the point: “[Christou & Koenderink, 1997] speculated that the [high degree of] constancy was most likely due to information provided by visible smooth occlusion contours. The present investigation WAS DESIGNED SPECIFICALLY TO TEST THAT SUGGESTION, and the RESULTS SHOW CLEARLY that the absence of smooth occlusions in the masked conditions had a NEGLIGIBLE IMPACT [all caps mine] on the overall pattern of performance.”

      So Christou and Koenderink's purportedly “reasonable” suggestion is apparently false. That's the point, and the authors shouldn't have been forced (or internalized a reequirement) to pussyfoot around it. They should have stated it as clearly up front as they do (eventually) in their discussion.

      Falsification of FALSE theories is how science proceeds, and you can't show they're false unless you actually target specific assumptions for testing. Of course, proponents of the idea may, if they'd like, and can, make counterarguments.

      So kudos to the authors for directly testing the claim, as they did in a previous article on an another ad hoc suggestion. Next time, I hope they adopt a more direct reporting style as well.

      But on theory, there's more to be said, starting with https://pubpeer.com/publications/1220D804D501BB15474B6D0F33FC7D


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    1. On 2015 Aug 20, Lydia Maniatis commented:

      The authors here report having “investigated how texture and stereo cues are integrated to perceive 3D slant.” The problem here (as with other literature dealing with the same topic) is with the unqualified references to “texture cues.”

      2D “textures” are composed of 2D shapes, and 2D shape is dispositive when it comes to the perception of slant. If I start with a rectangle (or syncytium of rectangles) and I slant it so that it produces a trapezoidal 2D projection, then this projection will look like a slanted rectangle. If I start with a trapezoid and slant it so that it casts a rectangular 2D projection, then it will look like a fronto-parallel rectangle, not a slanted trapezoid. Perceived slant is a function of the shape of the projection.

      Because shape is the key factor mediating apparent slant, and because textures are composed of shapes, saying that we will study the role of “texture” without specifying and controlling for the effects of the particular shapes of which the texture is composed is like proposing to investigate the role of “food cues” on blood pressure, without caring about what type of food we are employing as our “stimulus.” Such practice ensures the enduring confusion and ambiguity that characterizes slant studies, which often seem to contradict each other.

      This study used “Voronoi” textures. Why? An earlier study (Todd et al, 2010) used textures composed of rectangles orthographically projected. Yet another study referred to by Saunders and Chen used Voronoi textures that were more regular than theirs. Do the authors believe that by using the type of structure the do, in which the cells' shape varies, and which has a particular degree of irregularity, they are controlling for the effects of shape? To continue my previous analogy, this would be like assuming that mixing many foods together will control for the effect of the individual nutrients on blood pressure.

      If we know a variable matters, then we don't control for it by mixing it up its values, we control for it by controlling for it. “Food” in this analogy is obviously not an appropriate level of analysis, and the results will vary with the choice of “food.” The same goes for “texture.” What is left after we subtract shape? At the least, the authors should have provided some rationale for their choice of texture.

      There is no doubt whatsoever that the choice of “texture” affects perceived slant. Erkelens (2013) used a “texture” composed of rectangles under perspective projection and found very good agreement with prediction, and an underestimation at all slants. Saunders and Chen found underestimation at low slants, and not at higher ones. They should explain why this low/high dichotomy should be found in their particular conditions, including their choice of pattern, and not in, e.g., Erkelens'. (Are they suggesting that by using “Voronoi” patterns, they have isolated the role of “texture,” independently of shape, and that their results are more valid?)

      The authors' decision to deal with the potential role of the outline containing their texture by randomly varying this shape reflects the tendency to embed confounds in the data in the hope that they will average out (rather than distort or flatten the results – averaging black and white makes grey) rather than to confront and control for them head on.

      Of course, they found that “texture” cues and disparity cues are somehow integrated (the claim that they are “optimally” integrated is difficult to judge, as it has been preceded by layers of speculation). The basic findings were a sure thing. The specifics of the data are uninterpretable due to lack of control of relevant variables.


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    1. On 2015 Apr 24, CHARLES KING commented:

      I feel there is a serious methodological flaw in the recently published Cochrane Review “Circulating antigen tests and urine reagent strips for diagnosis of active schistosomiasis in endemic areas” by Ochodo, et el., 2015. The inaccurate analysis used in the HSROC estimation skews the reported summary results on the diagnostic performance of both antigen tests and dipsticks, and a correct analysis would actually invalidate several of the conclusions and recommendations found in the current version of the review: My objection is to the use of egg count diagnostics as a reference standard for the diagnosis of Schistosoma infection. The stool egg count for S. mansoni and S. japonicum and the urine filtration egg count for S. haematobium have long been known to be poorly sensitive for low intensity infections. When subjects are repeatedly tested for 7-15 days in a row, single day egg count testing has a sensitivity of 40-60%. Although these imperfect tests remain in widespread use in field studies and control campaigns because they accurately detect persons with heavy infections, they cannot be relied upon to establish infection in all subjects. The failings of stool counting for S. mansoni were documented in the work of de Vlas and colleagues cited below [1,2]. The limitations of stool counting for S. japonicum have been established by Carabin, et al.,[3] and Hubbard, et al.,[4] and the limitations of egg counting for S. haematobium can be found in Savioli et al.,[5] and Warren, et al.[6]

      In all cases, egg counting cannot be considered a ‘gold standard’ diagnostic. Such a test, with ~50% sensitivity, is so inaccurate to be useless on a per-individual diagnostic basis. I feel that the appropriate comparison for the Ochodo, et al., review would have been Latent Class Analysis, in which two imperfect tests are compared in their attempt to classify an unmeasured ‘true’ infection status. Using egg count results as a reference standard in the HSROC was a serious error--reporting a new test’s performance benchmarked against an already flawed test is meaningless, and in fact, the reported comparisons are misleading to the practitioner or public health officer.

      Secondly, I feel that the exclusion of results from populations or areas without significant Schistosoma risk was also a tactical error. If we are concerned about the specificity of new tests, there is great value in measuring results among persons who have a very low prior probability of infection.

      I would strongly recommend that the Cochrane review be revised and re-issued after the authors revisit the data using the approach of Dendukuri, et al., 2012 [7] for situations where there is no gold standard. Their SAS code is available online, and the reanalysis could be done in a matter of a day. The Bayesian LCA should be informed by prior observations on the estimated specificity of single (or treble stool) examinations, and the known specificity estimates of dipsticks and antigen testing among non-endemic populations.

      The concern is that while the authors discuss and reiterate the lack of a gold standard and the insensitivity of the egg count procedures they go right ahead and use them as their comparator and they present strong conclusions that are biased by their approach. This will only add to policymakers’ confusion about the utility of these alternative test approaches.

      By way of disclosure, I have no relation to the manufacturers of these tests, and I have no conflict of interest in this matter.

      1. de Vlas SJ, Engels D, Rabello AL, Oostburg BF, Van Lieshout L, Polderman AM, Van Oortmarssen GJ, Habbema JD, Gryseels B, 1997. Validation of a chart to estimate true Schistosoma mansoni prevalences from simple egg counts. Parasitology 114 ( Pt 2): 113-21.
      2. de Vlas SJ, Gryseels B, 1992. Underestimation of Schistosoma mansoni prevalences. Parasitol Today 8: 274-277.
      3. Carabin H, Marshall CM, Joseph L, Riley S, Olveda R, McGarvey ST, 2005. Estimating the intensity of infection with Schistosoma japonicum in villagers of Leyte, Philippines. Part I: A Bayesian cumulative logit model. The Schistosomiasis Transmission & Ecology Project (STEP). Am J Trop Med Hyg 72: 745-753.
      4. Hubbard A, Liang S, Maszle D, Qiu D, Gu X, Spear RC, 2002. Estimating the distribution of worm burden and egg excretion of Schistosoma japonicum by risk group in Sichuan Province, China. Parasitology 125: 221-31.
      5. Savioli L, Hatz C, Dixon H, Kisumku UM, Mott KE, 1990. Control of morbidity due to Schistosoma haematobium on Pemba Island: egg excretion and hematuria as indicators of infection. Am J Trop Med Hyg 43: 289-295.
      6. Warren KS, Arap Siongok TK, Hauser HB, Ouma JH, Peters PAS, 1978. Quantification of infection with Schistosoma haematobium in relation to epidemiology and selective population chemotherapy. I. Minimal number of daily egg counts in urine necessary to establish intensity of infection. Journal of Infectious Diseases 138: 849-55.
      7. Dendukuri N, Schiller I, Joseph L, Pai M, 2012. Bayesian meta-analysis of the accuracy of a test for tuberculous pleuritis in the absence of a gold standard reference. Biometrics 68: 1285-1293.


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    1. On 2015 Mar 11, Alexis Clapin commented:

      Congratulation for your work.

      I would like to draw your attention on one of the four selected studies: MSCRG 1999 study(1). This study compared whole brain atrophy in relapsing-remitting MS patients treated with either Avonex or a placebo. One hundred forty patients are selected for this comparison. These patients participated to the initial MSCRG 1996 study (2), which was stopped earlier than planned. Among the 301 patients included, 172 were followed up for two years. The 140 patients are thus drawn from these 172 patients.

      When reviewing the MSCRG 1996 study, the FDA analysed the efficacy of Avonex on the relapse rate for different subgroups of patients to check if, as Biogen said, there was a lag time between initiation of treatment and onset of clinical benefit. FDA reviewers demonstrated (3)that there was no lag time but that patients followed up for two years were different from those followed up for less than two years. During the first year of the study, Avonex patients followed up for less than two years experienced a +29% increase of the relapse rate versus placebo while patients followed up for at least two years experienced a -29% decrease versus placebo. During the second year, relapse rate did not change (-32%). FDA finally concluded that patients followed for two years were different from those followed up for less than two years, but did not provide a comparison of the subgroups.

      The group of patients followed up for two years is thus a very odd subgroup of the randomised patients in the initial MSCRG 1996 study (2); obviously there are favouring the positive evaluation of the product.

      For further explanation of the bias in the MSCRG 1996 study, you can see this analysis (4) on the MSCRG 1996 study (2).

      The Cochrane collaboration recently considered that Avonex had a negative benefit/risk ratio (5). Their risk of bias analysis for the MSCRG (1996) (2) is more negative than the one you provide for the MSCRG 1999 study (1). To conclude, I am not sure that you can consider MSCRG 1999 (2) patients study as an unbiased subgroup of the initial MSCRG 1996 study (1). It is just a comparison of a group of best responders to Avonex to a group of worst responders to placebo.

      (1)http://www.ncbi.nlm.nih.gov/pubmed/10563615 (2)http://www.ncbi.nlm.nih.gov/pubmed/8602746<br> (3)http://www.fda.gov/downloads/Drugs/DevelopmentApprovalProcess/HowDrugsareDevelopedandApproved/ApprovalApplications/TherapeuticBiologicApplications/ucm086056.pdf (4)http://www.ncbi.nlm.nih.gov/pubmed/23662092<br> (5)http://www.ncbi.nlm.nih.gov/pubmed/23744561


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    1. On 2015 Jul 10, Matthew Shirley commented:

      I won't discount the utility of writing your own software to solve a problem, but I do take issue with the fact that this application note does not mention (reference) except in supplement #1 the existence of existing mature tools that accomplish much of what VASP aims to provide. The authors also do not clearly state what about the software is novel or better that these existing tools (only that it "makes no assumptions regarding the underlying disease transmission mechanism", which other programs arguably allow by integrating the results from multiple parameterized runs?). To be clear, I do not think these are reasons to prevent publication or development of this program - I just find the presentation of the research results a bit misleading.


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    1. On 2017 Mar 25, Gerhard Holt commented:

      Eliminating S.A.S.P. cells : Targeting Senescence Specific Surface Antigens

      with CAR-T cells, mAbs or Minicells ?

                                                 by Gerhard Holt
      

      Research into cellular aging and the Senescence-Associated Secretory Phenotype indicates that selective elimination of senescent cells may provide substantial benefits - potentially including increases in healthspan.[1]

      Many surface antigens may be differentially expressed on senescent/SASP cells relative to non-senescent cells. Ideally, the chosen cell surface antigen(s) would be highly specific to senescent/SASP cells to reduce collateral damage to non-senescent cells. For example, EFNB1 and/or EFNB3 may be appealing targets.[1]

      These "Senescence Specific Surface Antigen" targets might - if necessary - include potentially spurious surface antigens that may have negligible causal relation to SASP but are nevertheless fairly specific. One could presumably also target multiple "SSSA"s to achieve better coverage.

      Several methods to target cells expressing these SSSA's might be used - including :

      (1) CAR-T cells vs the antigen(s). [2]

      Pros :

      Extensive removal of target cells. Long lasting surveillance against subsequent reemergence of the senescent/SASP cells with those surface antigens.

      Cons :

      May cause collateral damage or impair other important functions (for example - potentially - wound healing).

      Questions :

      Could one potentially embed a switchable "suicide gene" in the CAR-T cells, or perhaps a reversible switch to transiently deactivate the CAR-Ts either systemically or locally?

      Could one also embed a highly specific artificial set of inducible surface antigens on the CAR-Ts to facilitate subsequent removal or modification by mAbs or minicells (see below)?[3]

      (In the longer term one might also potentially examine logic-gated CAR-T cell approaches for increased specificity, or to target the absence of a surface antigen that is differentially expressed on Non-senescent cells ? [3])

      (2) mAbs vs the antigen(s).

      Pro :

      Well established approach.

      Con :

      No longer term surveillance.

      (3) Minicells vs the antigen(s). [4]

      Pros :

      Highly specific targeting. Minicells could also be targeted to multiple different SSSA's.

      Can specifically carry cytotoxic medications to the target cells.

      Can add siRNAs to the minicells to perform more subtle intracellular actions (perhaps inducing apoptosis, reversing (or accelerating) aberrant intracellular processes, attracting CAR-T cells, or modifying natural immune responses to the cell, or expressing alternative surface antigens).

      Could be used in addition to CAR-T approaches, or perhaps as a backup to help selectively deactivate CAR-T cells if responses cause excessive collateral damage or if one needs to (perhaps temporarily) damp the response.

      Con :

      No long term surveillance.

      Conclusion :

      Targeting senescence specific surface antigens may be a useful way to selectively destroy senescent/SASP cells.

      The application of CAR-T cell, mAb, and minicell approaches might be effective in this task, and will hopefully be the subject of further research.

      REFERENCES :

      [1] Zhu, Y. Tchkonia, T. et al. (2015) The Achilles' heel of senescent cells: from transcriptome to senolytic drugs. Aging Cell. 2015 Aug;14(4):644-58. doi: 10.1111/acel.12344. Epub 2015 Apr 22.

      www.ncbi.nlm.nih.gov/pubmed/25754370

      [2] Kochenderfer JN et al. (2010) Adoptive transfer of syngeneic T cells transduced with a chimeric antigen receptor that recognizes murine CD19 can eradicate lymphoma and normal B cells. Blood. 2010 Nov 11;116(19):3875-86. doi: 10.1182/blood-2010-01-265041. Epub 2010 Jul 14.

      www.bloodjournal.org/content/bloodjournal/116/19/3875.full.pdf

      [3] Roybal, K.T., et al. (2016). Precision tumor recognition by T cells with combinatorial antigen-sensing circuits. Cell 164, 770–779. dx.doi.org/10.1016/j.cell.2016.01.011

      www.sciencedirect.com/science/article/pii/S0092867416000519

      [4] MacDiarmid, J.A. et al. (2009) Sequential treatment of drug-resistant tumors with targeted minicells containing siRNA or a cytotoxic drug. Nat. Biotechnol. 27, 643–651.

      www.nature.com/nbt/journal/v27/n7/pdf/nbt.1547.pdf


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    1. On 2015 Mar 11, David Mage commented:

      This comment was written from reading this abstract the instant it was uploaded before the link to the pdf was added by PUBMED. A final comment is added at the end as a CODA that was made necessary when the article was read. The medical literature has at this instant of writing 10778 PUBMED returns for SIDS (some are not on sudden infant death syndrome but with the same acronym). Most of them are worthless shots-in-the-dark hoping to hit something. The burgeoning literature has an insatiable demand for content and editors and reviewers are not guarding the gates, as true experts cannot review every article submitted in their fields before publication. Hundreds of articles are written on small sample size studies that report a glimmer of a correlation of SIDS with something that they hope by some undiscovered alchemical legerdemain can be converted into a causation. And yet, as the sample size increases the vision of gold always becomes one of pyrites. Its like the fisherman hooking something big leading to visions of a record size catch, only to find when it breaks the surface that it is an old tire. Temperature is involved with SIDS but in the completely opposite direction. SIDS rate maximizes in the winter, not in the summer. Hawaii, a state without seasons, (O.K., maybe beautiful weather and very beautiful weather) has a maximum SIDS rate in the Northern hemisphere winter (Mage DT, 2004) that we relate to the higher incidence of respiratory infection in Japan and the continental U.S. by a tourist infection vector (Mage DT, 2009). This writer served with the WHO and spent 3.5 years in Malaysia where the tropical seasonal heat and humidity on a normal day would put Montreal to shame on its hottest and most humid day. O.K. now lets look at Canada (Mage DT, 2005). For years 1985-89 and 1994-1998 there were in all of Canada during the winter (Jan-Mar) 504 SIDS and 368 SIDS in the summer (Jul-Sep). Oh high temperature, where is thy sting? CODA: The authors wrote perceptively a la Trofim Desinovich Lysenko - "Another issue is that Taiwan has a mild climate with a population accustomed to heat, which may mitigate the impact of temperature on SIDS." Ah yes, the parental accomodation to heat by living in semi-tropical Taiwan is passed on through their mutated-genes to their offspring who at birth have their parent's ability to withstand the fearsome heat waves uniquely endemic to Taiwan.


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    1. On 2015 Jul 25, Kamaldeep Bhui commented:

      see also: Health Technol Assess. 2015 Apr;19(31):vii-xxiv, 1-173. doi: 10.3310/hta19310.

      If you're interested in this paper, see also:

      Interventions designed to improve therapeutic communications between black and minority ethnic people and professionals working in psychiatric services: a systematic review of the evidence for their effectiveness.

      Bhui K(1), Aslam RW(1), Palinski A(1), McCabe R(1), Johnson MR(2), Weich S(3), Singh SP(3), Knapp M(4), Ardino V(4), Szczepura A(3).

      We need more debate and research on the components of interventions to improve therapeutic communications, and engage socially excluded or hard to reach populations.


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    1. On 2015 Mar 19, David Keller commented:

      High-dose Coenzyme Q10 was safe in the Parkinson Study Group trial

      In their reply to my letter [1] pointing out that the doses of Coenzyme Q10 tested may have been too small to treat statin-induced myopathy, Banach and Mikhailidis state: "Another question is whether higher dosages of CoQ10 have adverse effects. Contemporary data concerning the administration of CoQ10 at dosages higher than 1200 mg/d are limited" [2].

      To address these safety concerns, consider the Parkinson Study Group's trial of high-dose CoQ10; 600 subjects with early Parkinson disease were randomized to placebo or to high-dose CoQ10. 94 subjects received placebo, 87 received 1200 mg/d of CoQ10, and 86 received 2400 mg/d of CoQ10 [3]. Only 65 participants withdrew prematurely: 29 who received placebo, 19 who received 1200 mg/d of CoQ10, and 17 who received 2400 mg/d of CoQ10, and it was reported that "treatments were well tolerated with no safety concerns".

      While it was disappointing that high-dose Coenzyme Q10 did not slow the progression of Parkinson's disease, at least we learned that doses of up to 2400 mg per day seem to be safe and well-tolerated.

      References

      1: Keller DL. Coenzyme Q10 and statin-induced myopathy--I. Mayo Clin Proc. 2015 Mar;90(3):419-20. doi: 10.1016/j.mayocp.2015.01.006. PubMed PMID: 25744125.

      2: Banach M, Mikhailidis DP; Lipid and Blood Pressure Meta-analysis Collaboration (LBPMC) Group. In reply-Coenzyme Q10 and Statin-Induced Myopathy. Mayo Clin Proc. 2015 Mar;90(3):420-1. doi: 10.1016/j.mayocp.2015.01.003. PubMed PMID: 25744127.

      3: Parkinson Study Group QE3 Investigators, A randomized clinical trial of high-dosage coenzyme Q10 in early Parkinson disease: no evidence of benefit. JAMA Neurol. 2014 May;71(5):543-52. doi: 10.1001/jamaneurol.2014.131. PubMed PMID: 24664227.


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    1. On 2015 Mar 10, Donald Forsdyke commented:

      ADAPTATION DECOUPLED FROM SPECIATION. This fine new paper presents an impressive synthesis of phylogenetic data aiming to “explore how it bears on evolutionary hypotheses and mechanisms of speciation and diversification.” In keeping with the results of Venditti et al. (2010) that are cited, the major conclusion is that “if adaptation is largely decoupled from speciation, we should not expect it to be a driver of speciation.” Indeed, “Cases where the phenotype has changed little (e.g. cryptic species) … are interpreted here as evidence of uncoupling.” There is reference to geographic isolation as “the major model,” but it is noted that “time constraints should be similar with ecological speciation, and other models exist.”

      One of these “other models” is considered by Venditti et al. (2008 Biologist 55, 140-146), who note: “There is a growing appreciation amongst evolutionary biologists that rapid reproductive isolation is more common than previously thought and is often associated with what is known as sympatric speciation, or speciation between populations which share the same geographic range.” The idea of a non-geographic decoupling of adaptation from speciation was advanced by Darwin’s research associate George Romanes in 1886. As with Venditti et al. (2010), the present results nicely support Romanes, whose work is the major focus of my speciation text (The Origin of Species, Revisited, McGill-Queen's University Press, 2001). There is further elaboration both in our biography of the geneticist William Bateson (Treasure Your Exceptions, Springer, New York, 2008) and in my textbook Evolutionary Bioinformatics (Springer, New York, 2011).


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    1. On 2015 Jul 25, Egon Willighagen commented:

      David, you may want to read with J. Wales has to say about this [0]:

      But if the Professor has a more nuanced view that Wikipedia should not be cited "as a source" by university students then I agree completely! I think the same thing about citing Britannica or any other encyclopedia. Citing an encyclopedia for an academic paper at the University level is not appropriate

      0.http://www.quora.com/What-does-Jimmy-Wales-think-when-a-university-professor-discourages-students-from-citing-Wikipedia-as-a-primary-or-secondary-source


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