Structural dichroism in the antiferromagnetic insulating phase of V_2O_3

We performed near-edge x-ray absorption spectroscopy (XANES) at V K edge in the antiferromagnetic insulating (AFI) phase of a 2.8% Cr-doped V_2O_3 single crystal. Linear dichroism of several percent is measured in the hexagonal plane and found to be in good agreement with ab-initio calculations based on multiple scattering theory. This experiment definitively proves the structural origin of the signal and therefore solves a controversy raised by previous interpretations of the same dichroism as non-reciprocal. It also calls for a further investigation of the role of the magnetoelectric annealing procedure in cooling to the AFI phase.Comment: 4 pages 3 figures. To be published in Phys. Rev. B (2005

Functional characterization of the sciarid BhC4-1 core promoter in transgenic Drosophila

<p>Abstract</p> <p>Background</p> <p>Core promoters are <it>cis</it>-regulatory modules to which bind the basal transcriptional machinery and which participate in the regulation of transcription initiation. Although core promoters have not been extensively investigated through functional assays in a chromosomal context, the available data suggested that the response of a given core promoter might vary depending on the promoter context. Previous studies suggest that a (-57/+40) fragment constitutes the core promoter of the <it>BhC4-1 </it>gene which is located in DNA puff C4 of the sciarid fly <it>Bradysia hygida</it>. Here we tested this (-57/+40) fragment in distinct regulatory contexts in order to verify if promoter context affects its core promoter activity.</p> <p>Results</p> <p>Consistent with the activity of a core promoter, we showed that in the absence of upstream regulatory sequences the (-57/+40) fragment drives low levels of reporter gene mRNA expression throughout development in transgenic <it>Drosophila</it>. By assaying the (-57/+40) fragment in two distinct regulatory contexts, either downstream of the previously characterized <it>Fbp1 </it>enhancer or downstream of the UAS element, we showed that the <it>BhC4-1 </it>core promoter drives regulated transcription in both the germline and in various tissues throughout development. Furthermore, the use of the <it>BhC4-1 </it>core promoter in a UAS construct significantly reduced salivary gland ectopic expression in third instar larvae, which was previously described to occur in the context of the GAL4/UAS system.</p> <p>Conclusions</p> <p>Our results from functional analysis in transgenic <it>Drosophila </it>show that the <it>BhC4-1 </it>core promoter drives gene expression regardless of the promoter context that was assayed. New insights into the functioning of the GAL4/UAS system in <it>Drosophila </it>were obtained, indicating that the presence of the SV40 sequence in the 3' UTR of a UAS construct does not preclude expression in the germline. Furthermore, our analysis indicated that ectopic salivary gland expression in the GAL4/UAS system does not depend only on sequences present in the GAL4 construct, but can also be affected by the core promoter sequences in the UAS construct. In this context, we propose that the sciarid <it>BhC4-1 </it>core promoter constitutes a valuable core promoter which can be employed in functional assays in insects.</p

All-cause mortality and estimated renal function in type 2 diabetes mellitus outpatients: is there a relationship with the equation used?

BACKGROUND: We investigated the relationship between serum creatinine (SCr) and estimated glomerular filtration rate (eGFR), evaluated by different formulae, and all-cause mortality (ACM) in type 2 diabetes mellitus (T2DM) outpatients. METHODS: This observational cohort study considered 1365 T2DM outpatients, who had been followed up for a period of up to 11 years. eGFR was estimated using several equations. RESULTS: Seventy subjects (5.1%) died after a follow-up of 9.8 ± 3 years. Univariate analysis showed that diagnosis of nephropathy (odds ratio (OR): 2.554, 95% confidence interval (CI): 1.616-4.038, p < 0.001) and microvascular complications (OR: 2.281, 95% CI: 1.449-3.593, p < 0.001) were associated with ACM. Receiving operating characteristic (ROC) curves showed that the areas under the curve for ACM were similar using the different eGFR equations. eGFR values were predictors of ACM, and the hazard ratios (HRs) of the different equations for eGFR estimation were similar. CONCLUSION: In our cohort of T2DM outpatients, different eGFR equations perform similarly in predicting ACM, whereas SCr did not

Blood component therapy and coagulopathy in trauma: A systematic review of the literature from the trauma update group

Background Traumatic coagulopathy is thought to increase mortality and its treatment to reduce preventable deaths. However, there is still uncertainty in this field, and available literature results may have been overestimated. Methods We searched the MEDLINE database using the PubMed platform. We formulated four queries investigating the prognostic weight of traumatic coagulopathy defined according to conventional laboratory testing, and the effectiveness in reducing mortality of three different treatments aimed at contrasting coagulopathy (high fresh frozen plasma/packed red blood cells ratios, fibrinogen, and tranexamic acid administration). Randomized controlled trials were selected along with observational studies that used a multivariable approach to adjust for confounding. Strict criteria were adopted for quality assessment based on a two-step approach. First, we rated quality of evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria. Then, this rating was downgraded if other three criteria were not met: high reporting quality according to shared standards, absence of internal methodological and statistical issues not detailed by the GRADE system, and absence of external validity issues. Results With few exceptions, the GRADE rating, reporting and methodological quality of observational studies was "very low", with frequent external validity issues. The only two randomized trials retrieved were, instead, of high quality. Only weak evidence was found for a relation between coagulopathy and mortality. Very weak evidence was found supporting the use of fibrinogen administration to reduce mortality in trauma. On the other hand, we found high evidence that the use of 1:1 vs. 1:2 high fresh frozen plasma/packed red blood cells ratios failed to obtain a 12% mortality reduction. This does not exclude lower mortality rates, which have not been investigated. The use of tranexamic acid in trauma was supported by "high" quality evidence according to the GRADE classification but was downgraded to "moderate" for external validity issues. Conclusions Tranexamic acid is effective in reducing mortality in trauma. The other transfusion practices we investigated have been inadequately studied in the literature, as well as the independent association between mortality and coagulopathy measured with traditional laboratory testing. Overall, in this field of research literature quality is poor

Factors that could explain the increasing prevalence of type 2 diabetes among adults in a Canadian province: a critical review and analysis

Abstract: Background: The prevalence of diabetes has increased since the last decade in New Brunswick. Identifying factors contributing to the increase in diabetes prevalence will help inform an action plan to manage the condition. The objective was to describe factors that could explain the increasing prevalence of type 2 diabetes in New Brunswick since 2001. Methods: A critical literature review was conducted to identify factors potentially responsible for an increase in prevalence of diabetes. Data from various sources were obtained to draw a repeated cross-sectional (2001–2014) description of these factors concurrently with changes in the prevalence of type 2 diabetes in New Brunswick. Linear regressions, Poisson regressions and Cochran Armitage analysis were used to describe relationships between these factors and time. Results: Factors identified in the review were summarized in five categories: individual-level risk factors, environmental risk factors, evolution of the disease, detection effect and global changes. The prevalence of type 2 diabetes has increased by 120% between 2001 and 2014. The prevalence of obesity, hypertension, prediabetes, alcohol consumption, immigration and urbanization increased during the study period and the consumption of fruits and vegetables decreased which could represent potential factors of the increasing prevalence of type 2 diabetes. Physical activity, smoking, socioeconomic status and education did not present trends that could explain the increasing prevalence of type 2 diabetes. During the study period, the mortality rate and the conversion rate from prediabetes to diabetes decreased and the incidence rate increased. Suggestion of a detection effect was also present as the number of people tested increased while the HbA1c and the age at detection decreased. Period and birth cohort effect were also noted through a rise in the prevalence of type 2 diabetes across all age groups, but greater increases were observed among the younger cohorts. Conclusions: This study presents a comprehensive overview of factors potentially responsible for population level changes in prevalence of type 2 diabetes. Recent increases in type 2 diabetes in New Brunswick may be attributable to a combination of some individual-level and environmental risk factors, the detection effect, the evolution of the disease and global changes

Meiotic silencing and fragmentation of the male germline restricted chromosome in zebra finch

During male meiotic prophase in mammals, X and Y are in a largely unsynapsed configuration, which is thought to trigger meiotic sex chromosome inactivation (MSCI). In avian species, females are ZW, and males ZZ. Although Z and W in chicken oocytes show complete, largely heterologous synapsis, they too undergo MSCI, albeit only transiently. The W chromosome is already inactive in early meiotic prophase, and inactive chromatin marks may spread on to the Z upon synapsis. Mammalian MSCI is considered as a specialised form of the general meiotic silencing mechanism, named meiotic silencing of unsynapsed chromatin (MSUC). Herein, we studied the avian form of MSUC, by analysing the behaviour of the peculiar germline restricted chromosome (GRC) that is present as a single copy in zebra finch spermatocytes. In the female germline, this chromosome is present in two copies, which normally synapse and recombine. In contrast, during male meiosis, the single GRC is always eliminated. We found that the GRC in the male germline is silenced from early leptotene onwards, similar to the W chromosome in avian oocytes. The GRC remains largely unsynapsed throughout meiotic prophase I, although patches of SYCP1 staining indicate that part of the GRC may self-synapse. In addition, the GRC is largely devoid of meiotic double strand breaks. We observed a lack of the inner centromere protein INCENP on the GRC and elimination of the GRC following metaphase I. Subsequently, the GRC forms a micronucleus in which the DNA is fragmented. We conclude that in contrast to MSUC in mammals, meiotic silencing of this single chromosome in the avian germline occurs prior to, and independent of DNA double strand breaks and chromosome pairing, hence we have named this phenomenon meiotic silencing prior to synapsis (MSPS)

Identification of unannotated exons of low abundance transcripts in Drosophila melanogaster and cloning of a new serine protease gene upregulated upon injury

<p>Abstract</p> <p>Background</p> <p>The sequencing of the <it>D.melanogaster </it>genome revealed an unexpected small number of genes (~ 14,000) indicating that mechanisms acting on generation of transcript diversity must have played a major role in the evolution of complex metazoans. Among the most extensively used mechanisms that accounts for this diversity is alternative splicing. It is estimated that over 40% of <it>Drosophila </it>protein-coding genes contain one or more alternative exons. A recent transcription map of the <it>Drosophila </it>embryogenesis indicates that 30% of the transcribed regions are unannotated, and that 1/3 of this is estimated as missed or alternative exons of previously characterized protein-coding genes. Therefore, the identification of the variety of expressed transcripts depends on experimental data for its final validation and is continuously being performed using different approaches. We applied the Open Reading Frame Expressed Sequence Tags (ORESTES) methodology, which is capable of generating cDNA data from the central portion of rare transcripts, in order to investigate the presence of hitherto unnanotated regions of <it>Drosophila </it>transcriptome.</p> <p>Results</p> <p>Bioinformatic analysis of 1,303 <it>Drosophila </it>ORESTES clusters identified 68 sequences derived from unannotated regions in the current <it>Drosophila </it>genome version (4.3). Of these, a set of 38 was analysed by polyA⁺northern blot hybridization, validating 17 (50%) new exons of low abundance transcripts. For one of these ESTs, we obtained the cDNA encompassing the complete coding sequence of a new serine protease, named SP212. The <it>SP212 </it>gene is part of a serine protease gene cluster located in the chromosome region 88A12-B1. This cluster includes the predicted genes CG9631, CG9649 and CG31326, which were previously identified as up-regulated after immune challenges in genomic-scale microarray analysis. In agreement with the proposal that this <it>locus </it>is co-regulated in response to microorganisms infection, we show here that SP212 is also up-regulated upon injury.</p> <p>Conclusion</p> <p>Using the ORESTES methodology we identified 17 novel exons from low abundance <it>Drosophila </it>transcripts, and through a PCR approach the complete CDS of one of these transcripts was defined. Our results show that the computational identification and manual inspection are not sufficient to annotate a genome in the absence of experimentally derived data.</p

Evaluating the Relationship between Spermatogenic Silencing of the X Chromosome and Evolution of the Y Chromosome in Chimpanzee and Human

Chimpanzees and humans are genetically very similar, with the striking exception of their Y chromosomes, which have diverged tremendously. The male-specific region (MSY), representing the greater part of the Y chromosome, is inherited from father to son in a clonal fashion, with natural selection acting on the MSY as a unit. Positive selection might involve the performance of the MSY in spermatogenesis. Chimpanzees have a highly polygamous mating behavior, so that sperm competition is thought to provide a strong selective force acting on the Y chromosome in the chimpanzee lineage. In consequence of evolution of the heterologous sex chromosomes in mammals, meiotic sex chromosome inactivation (MSCI) results in a transcriptionally silenced XY body in male meiotic prophase, and subsequently also in postmeiotic repression of the sex chromosomes in haploid spermatids. This has evolved to a situation where MSCI has become a prerequisite for spermatogenesis. Here, by analysis of microarray testicular expression data representing a small number of male chimpanzees and men, we obtained information indicating that meiotic and postmeiotic X chromosome silencing might be more effective in chimpanzee than in human spermatogenesis. From this, we suggest that the remarkable reorganization of the chimpanzee Y chromosome, compared to the human Y chromosome, might have an impact on its meiotic interactions with the X chromosome and thereby on X chromosome silencing in spermatogenesis. Further studies will be required to address comparative functional aspects of MSCI in chimpanzee, human, and other placental mammals

Disease-specific and general health-related quality of life in newly diagnosed prostate cancer patients: The Pros-IT CNR study

Background: The National Research Council (CNR) prostate cancer monitoring project in Italy (Pros-IT CNR) is an observational, prospective, ongoing, multicentre study aiming to monitor a sample of Italian males diagnosed as new cases of prostate cancer. The present study aims to present data on the quality of life at time prostate cancer is diagnosed. Methods: One thousand seven hundred five patients were enrolled. Quality of life is evaluated at the time cancer was diagnosed and at subsequent assessments via the Italian version of the University of California Los Angeles-Prostate Cancer Index (UCLA-PCI) and the Short Form Health Survey (SF-12). Results: At diagnosis, lower scores on the physical component of the SF-12 were associated to older ages, obesity and the presence of 3+ moderate/severe comorbidities. Lower scores on the mental component were associated to younger ages, the presence of 3+ moderate/severe comorbidities and a T-score higher than one. Urinary and bowel functions according to UCLA-PCI were generally good. Almost 5% of the sample reported using at least one safety pad daily to control urinary loss; less than 3% reported moderate/severe problems attributable to bowel functions, and sexual function was a moderate/severe problem for 26.7%. Diabetes, 3+ moderate/severe comorbidities, T2 or T3-T4 categories and a Gleason score of eight or more were significantly associated with lower sexual function scores at diagnosis. Conclusions: Data collected by the Pros-IT CNR study have clarified the baseline status of newly diagnosed prostate cancer patients. A comprehensive assessment of quality of life will allow to objectively evaluate outcomes of different profile of care