Is cowpox misnamed? A review of 10 human cases.

Twelve separate outbreaks of confirmed cowpox, 10 involving humans, were reviewed. Six of the patients, including three children, had severe infections and five were admitted to hospital. In three outbreaks both people and cows were affected but it was not known how the infections entered the herds. In seven outbreaks no direct contact with cattle was established and clinical and serological examination failed to show evidence of cowpox in the bovine population. Comparison of these data with information about infections known to be enzootic in cattle leads to the suggestion that cows are not the natural reservoir of cowpox. This should be remembered when diagnosis is considered. The role of small wild animals as hosts and vectors of "cowpox" should be investigated.     

Is confidence in the monitoring of GE foods justified?

Often the limits of detection of genetically engineered organisms (GEOs, LMOs, GMOs) determine what legislation sets as thresholds of allowable contamination of the human food chain with GEOs. Many countries have legislation that is triggered by certain thresholds of contamination. Importantly, international trade in food and animal feed is becoming increasingly vulnerable to interruptions caused by the ambiguity GEOs can create when shipments are monitored at the border. We examine the tools available for detection. Four key error-generating stages are identified with the aim of prompting a higher uniform standard of routine analysis at export and import points. Contamination of the New Zealand corn crop with GEOs is used as a case study for the application of monitoring tools and vulnerability to errors. These tools fail to meet emerging food safety requirements, but some improvements are in development.     

Is LB1 diseased or modern? A review of the proposed pathologies

The fossil remains of Homo floresiensis have been debated extensively over the past few years. This paper gives a review of the various pathologies ascribed to LB1, the type specimen of H. floresiensis, and associated individuals. This paper will assess the arguments for growth anomalies, microcephaly, Laron syndrome and cretinism. Additionally, some of the analyses done by proponents of the pathology theory will be methodologically evaluated. Subsequently, a brief overview of the alternative hypotheses regarding the origin of H. floresiensis will be given.     

Is the German suspension of MON810 maize cultivation scientifically justified?

We examined the justifications invoked by the German government in April 2009 to suspend the cultivation of the genetically modified maize varieties containing the Bt insect-resistance trait MON810. We have carried out a critical examination of the alleged new data on a potential environmental impact of these varieties, namely two scientific papers describing laboratory force-feeding trials on ladybirds and daphnia, and previous data on Lepidoptera, aquatic and soil organisms. We demonstrate that the suspension is based on an incomplete list of references, ignores the widely admitted case-by-case approach, and confuses potential hazard and proven risk in the scientific procedure of risk assessment. Furthermore, we did not find any justification for this suspension in our extensive survey of the scientific literature regarding possible effects under natural field conditions on non-target animals. The vast majority of the 41 articles published in 2008 and 2009 indicate no impact on these organisms and only two articles indicate a minor effect, which is either inconsistent during the planting season or represents an indirect effect. Publications from 1996 to 2008 (376 publications) and recent meta-analyses do not allow to conclude on consistent effects either. The lower abundance of some insects concerns mainly specialized enemies of the target pest (an expected consequence of its control by Bt maize). On the contrary, Bt maize have generally a lower impact than insecticide treatment. The present review demonstrates that the available meta-knowledge on Cry1Ab expressing maize was ignored by the German government which instead used selected individual studies.     

Is it possible to define a better ASCUS class in cervicovaginal screening? A review of 187 cases

OBJECTIVE: To try to better define the cytologic diagnosis of atypical squamous cells of undetermined significance (ASCUS) in a cervical screening protocol. STUDY DESIGN: Smears from 187 patients with cytologic diagnoses of ASCUS and histologic or two years' cytologic/colposcopic follow-up were reviewed. When an ASCUS diagnosis was confirmed, it was done strictly on the basis of the morphologic criteria recommended by the Regione Emilia Romagna Screening Protocol in 1997, trying also to subclassify ASCUS into favor reactive or favor neoplasia. RESULTS: Seventy ASCUS cases were negative (37.4%). Three cases (1.6%) were low grade squamous intraepithelial lesion, and seven (3.8%) were high grade squamous intraepithelial lesion. One hundred seven ASCUS cases (57.2%) were confirmed. Among the 70 negative cases, 36 (51.4%) had reactive changes on biopsy, 30 (42.9%) koilocytosis, 3 cervical intraepithelial neoplasia (CIN 1) and one CIN not otherwise specified (5.7% total). CONCLUSION: Reclassification of ASCUS cases using tighter criteria reduced them to a rate of 57.2% but missed 30 patients with histologic diagnoses of koilocytosis and 4 with histologic diagnoses of CIN.     

Zinner’s syndrome: report of two cases and review of the literature

Background

Congenital malformations of the seminal vesicle are uncommon, and most of them are cystic malformations. If an insult occurs between the 4th and the 13 h gestational week, the embryogenesis of the kidney, ureter, seminal vesicle, and vas deferens could be altered. Cysts of the seminal vesicle may appear with a mass effect, dysuria, epididymitis, or obstruction of the gastrointestinal and genitourinary tracts. Approximately two thirds of them are associated with ipsilateral renal agenesis, because both the ureteral buds and seminal vesicles originate from the mesonephric (Wolffian) duct. They were first described by Zinner in 1914, and 200 cases of seminal vesicle cysts associated with ipsilateral renal agenesis have been reported in the literature. Most patients with this anomaly are asymptomatic until the third or fourth decade of life. Some cases have nonspecific symptoms such as prostatism, urinary urgency, dysuria, painful ejaculation, and perineal discomfort. Transrectal ultrasonography provides good visualization of the pelvic structures and allows guidance for aspiration of the cysts.

Case presentation

We present two cases of seminal vesicle cyst. The first patient had dysuria, increased frequency of urination, and haematuria. He was operated and benefited from a removal of the cyst with right ureterectomy and left ureteral reimplantation. The second patient had disorder of the digestive transit and he benefited from a laparoscopic removal of the cyst.

Conclusions

Seminal vesicle cysts combined with ipsilateral renal agenesis are rare urological anomalies. Usual symptoms that are caused by the seminal vesicle cysts are bladder irritation and obstruction as well as pain in the perineum and scrotum. Epididymitis is frequently found. Treatment consists to removing the seminal vesicle cyst.

     

Does the type of matrix matter? A quantitative review of the evidence

It has been increasingly recognized that the type of matrix surrounding habitat patches can affect biodiversity in landscapes, but there were only qualitative reviews of the subject focused on particular taxonomic groups. We present a quantitative review of studies from 1985 to 2008 that compared effects of different matrix types on individuals, populations and communities. We compiled 104 studies, most on animals, covering a broad range of landscape types and spatial scales. Most studies were empirical, focused on individuals and communities, and evaluated abundance/richness in the patch as the dependent variable. The type of matrix surrounding habitat patches influenced the studied parameters in 95% of the studies, but such effects were overall smaller compared to patch size or isolation effects. Matrix type effects were strongly species-specific, with different species responding differently to matrix type in 96% of studies comparing species or group of species. In 88% of studies, matrix types more similar in structure to the patch had higher quality for the studied organisms from the point of view of functional connectivity. Overall, the type of matrix is important, but patch size and isolation are the main determinants of ecological parameters in landscapes. Matrix quality generally increases with increasing structural similarity with habitat patches, a pattern that could be used as a general guideline for management of the matrix in fragmented landscapes.     

ATP synthase: what dictates the size of a ring?

Recent data suggest the source of F(0)F(1) ATP synthase determines a significant and surprising difference in the size of a putative rotating ring of integral membrane subunits of F(0); this can be correlated with biochemical data suggesting there is variation in the number of protons translocated per ATP synthesised.     

The review of randomization in the Canadian National Breast Screening Study: Is the debate over?

The randomization procedure in the Canadian National Breast Screening Study (NBSS) is assessed in this issue (see pages 193 to 199) by Drs. John C. Bailar III and Brian MacMahon. They conclude that although there was ample opportunity for the randomization process to be subverted, no evidence of subversion was found. This is unlikely to allay all concerns about randomization, because there are still puzzling differences between the arms of the NBSS in a number of baseline variables. For example, the existence of prior health claims for breast cancer for women who entered the NBSS in Manitoba has raised the possibility that subversion occurred. Although the question may never be resolved, one lesion is clear: randomization in clinical trials should be managed in a manner that makes subversion impossible. As for the clinical implications of the NBSS for women in their 40s, physicians may now look to the results of randomized trials that have been published more recently. A meta-analysis of these results suggests that screening mammography reduces deaths from breast cancer among women in their 40s, but continued follow-up over the next few years will be needed to settle the debate.     

A review of criticisms of phylogenetic nomenclature: is taxonomic freedom the fundamental issue?

The proposal to implement a phylogenetic nomenclatural system governed by the PhyloCode), in which taxon names are defined by explicit reference to common descent, has met with strong criticism from some proponents of phylogenetic taxonomy (taxonomy based on the principle of common descent in which only clades and species are recognized). We examine these criticisms and find that some of the perceived problems with phylogenetic nomenclature are based on misconceptions, some are equally true of the current rank-based nomenclatural system, and some will be eliminated by implementation of the PhyloCode. Most of the criticisms are related to an overriding concern that, because the meanings of names are associated with phylogenetic pattern which is subject to change, the adoption of phylogenetic nomenclature will lead to increased instability in the content of taxa. This concern is associated with the fact that, despite the widespread adoption of the view that taxa are historical entities that are conceptualized based on ancestry, many taxonomists also conceptualize taxa based on their content. As a result, critics of phylogenetic nomenclature have argued that taxonomists should be free to emend the content of taxa without constraints imposed by nomenclatural decisions. However, in phylogenetic nomenclature the contents of taxa are determined, not by the taxonomist, but by the combination of the phylogenetic definition of the name and a phylogenetic hypothesis. Because the contents of taxa, once their names are defined, can no longer be freely modified by taxonomists, phylogenetic nomenclature is perceived as limiting taxonomic freedom. We argue that the form of taxonomic freedom inherent to phylogenetic nomenclature is appropriate to phylogenetic taxonomy in which taxa are considered historical entities that are discovered through phylogenetic analysis and are not human constructs.     

Alpha,beta-elimination reaction of O-acetylserine sulfhydrylase. Is the pyridine ring required?

O-Acetylserine sulfhydrylase (OASS) catalyzes the elimination of acetate from O-acetyl-L-serine (OAS) followed by addition of bisulfide to give L-cysteine. Site-directed mutagenesis has been used to replace the active site serine, S272, which forms a hydrogen bond to N1 of pyridoxal 5'-phosphate (PLP) with alanine and aspartate. Based on UV-visible spectral and steady-state kinetic studies, both mutant enzymes catalyze the elimination reaction with an efficiency equal to that of the wild-type enzyme. Data are consistent with an anti-E(2) reaction proposed for the elimination reaction.     

Epstein�CBarr virus-associated inflammatory pseudotumor of the spleen: report of two cases and review of the literature

We report two rare examples of Epstein–Barr virus (EBV)-associated inflammatory pseudotumor of the spleen. One patient presented with night sweats, abdominal pain, and weight loss and was found to have a splenic mass on CT scan suspected of lymphoma. The splenic mass in second patient was found incidentally at the time of work up for kidney stones. The pathologic examination of these splenectomy specimens showed similar histologic features. However, the spindle cells were composed of EBV-infected follicular dendritic cells in one case whereas the second case lacked significant follicular dendritic cell proliferation and showed only focal EBV-infected cells suggesting that these proliferations are heterogenous in nature.     

Is Qualitative Research Second Class Science? A Quantitative Longitudinal Examination of Qualitative Research in Medical Journals

Background

Qualitative research appears to be gaining acceptability in medical journals. Yet, little is actually known about the proportion of qualitative research and factors affecting its publication. This study describes the proportion of qualitative research over a 10 year period and correlates associated with its publication.

Design

A quantitative longitudinal examination of the proportion of original qualitative research in 67 journals of general medicine during a 10 year period (1998–2007). The proportion of qualitative research was determined by dividing original qualitative studies published (numerator) by all original research articles published (denominator). We used a generalized estimating equations approach to assess the longitudinal association between the proportion of qualitative studies and independent variables (i.e. journals'' country of publication and impact factor; editorial/methodological papers discussing qualitative research; and specific journal guidelines pertaining to qualitative research).

Findings

A 2.9% absolute increase and 3.4-fold relative increase in qualitative research publications occurred over a 10 year period (1.2% in 1998 vs. 4.1% in 2007). The proportion of original qualitative research was independently and significantly associated with the publication of editorial/methodological papers in the journal (b = 3.688, P = 0.012); and with qualitative research specifically mentioned in guidelines for authors (b = 6.847, P<0.001). Additionally, a higher proportion of qualitative research was associated only with journals published in the UK in comparison to other countries, yet with borderline statistical significance (b = 1.776, P = 0.075). The journals'' impact factor was not associated with the publication of qualitative research.

Conclusions

Despite an increase in the proportion of qualitative research in medical journals over a 10 year period, the proportion remains low. Journals'' policies pertaining to qualitative research, as expressed by the appearance of specific guidelines and editorials/methodological papers on the subject, are independently associated with the publication of original qualitative research; irrespective of the journals'' impact factor.     

Mitotic death: a mechanism of survival? A review

Mitotic death is a delayed response of p53 mutant tumours that are resistant to genotoxic damage. Questions surround why this response is so delayed and how its mechanisms serve a survival function. After uncoupling apoptosis from G1 and S phase arrests and adapting these checkpoints, p53 mutated tumour cells arrive at the G2 compartment where decisions regarding survival and death are made. Missed or insufficient DNA repair in G1 and S phases after severe genotoxic damage results in cells arriving in G2 with an accumulation of point mutations and chromosome breaks. Double strand breaks can be repaired by homologous recombination during G2 arrest. However, cells with excessive chromosome lesions either directly bypass the G2/M checkpoint, starting endocycles from G2 arrest, or are subsequently detected by the spindle checkpoint and present with the features of mitotic death. These complex features include apoptosis from metaphase and mitosis restitution, the latter of which can also facilitate transient endocycles, producing endopolyploid cells. The ability of cells to initiate endocycles during G2 arrest and mitosis restitution most likely reflects their similar molecular environments, with down-regulated mitosis promoting factor activity. Resulting endocycling cells have the ability to repair damaged DNA, and although mostly reproductively dead, in some cases give rise to mitotic progeny. We conclude that the features of mitotic death do not simply represent aberrations of dying cells but are indicative of a switch to amitotic modes of cell survival that may provide additional mechanisms of genotoxic resistance.