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  • Carstens Lyons posted an update 1 week, 2 days ago

    Four cases of a rare melanotic variant of malignant nerve sheath tumour (MNST) in dogs are described. All four cases presented with neurological clinical signs due to multicentric, intradural, intra- and extraparenchymal neoplasms that surrounded the spinal and cranial nerves and infiltrated the adjacent spinal cord and brain. The dogs were young (3 months to 3 years of age), all were female and four different breeds were represented. Characteristic histological features were interweaving fascicles of spindle-shaped cells, sometimes with an architecture reminiscent of Antoni A and B patterns. Some spindle cells showed prominent cytoplasmic melanin pigmentation and such cells were positive by Masson-Fontana stain. Immunohistochemistry performed in three cases was positive for S100 and vimentin, strongly positive for melan A in the melanized cells and negative for glial fibrillary acidic protein and periaxin. Non-melanized cells did not express melan A. Transmission electron microscopy findings in one case were consistent with a peripheral nerve sheath tumour and demonstrated cytoplasmic pre-melanosomes and melanosomes. Melanotic variants of MNSTs are rare in animals with only a solitary report of two previous canine cases in the literature.

    The appropriate age range for breast cancer screening remains a matter of debate. We aimed to estimate the effect of mammographic screening at ages 40-48 years on breast cancer mortality.

    We did a randomised, controlled trial involving 23 breast screening units across Great Britain. We randomly assigned women aged 39-41 years, using individual randomisation, stratified by general practice, in a 12 ratio, to yearly mammographic screening from the year of inclusion in the trial up to and including the calendar year that they reached age 48 years (intervention group), or to standard care of no screening until the invitation to their first National Health Service Breast Screening Programme (NHSBSP) screen at approximately age 50 years (control group). RO4987655 Women in the intervention group were recruited by postal invitation. Women in the control group were unaware of the study. The primary endpoint was mortality from breast cancers (with breast cancer coded as the underlying cause of death) diagnosed during the intring after more than 10 years of follow-up (RR 0·98 [0·79-1·22]; p=0·86).

    Yearly mammography before age 50 years, commencing at age 40 or 41 years, was associated with a relative reduction in breast cancer mortality, which was attenuated after 10 years, although the absolute reduction remained constant. Reducing the lower age limit for screening from 50 to 40 years could potentially reduce breast cancer mortality.

    National Institute for Health Research Health Technology Assessment programme.

    National Institute for Health Research Health Technology Assessment programme.Many organs are formed through folding of an epithelium. This change in shape is usually attributed to tissue heterogeneities, for example, local apical contraction. In contrast, compressive stresses have been proposed to fold a homogeneous epithelium by buckling. While buckling is an appealing mechanism, demonstrating that it underlies folding requires measurement of the stress field and the material properties of the tissue, which are currently inaccessible in vivo. Here, we show that monolayers of identical cells proliferating on the inner surface of elastic spherical shells can spontaneously fold. By measuring the elastic deformation of the shell, we infer the forces acting within the monolayer and its elastic modulus. Using analytical and numerical theories linking forces to shape, we find that buckling quantitatively accounts for the shape changes of our monolayers. Our study shows that forces arising from epithelial growth in three-dimensional confinement are sufficient to drive folding by buckling.The aggregation and joint analysis of large numbers of exome sequences has recently made it possible to derive estimates of intolerance to loss-of-function (LoF) variation for human genes. Here, we demonstrate strong and widespread coupling between genic LoF intolerance and promoter CpG density across the human genome. Genes downstream of the most CpG-rich promoters (top 10% CpG density) have a 67.2% probability of being highly LoF intolerant, using the LOEUF metric from gnomAD. This is in contrast to 7.4% of genes downstream of the most CpG-poor (bottom 10% CpG density) promoters. Combining promoter CpG density with exonic and promoter conservation explains 33.4% of the variation in LOEUF, and the contribution of CpG density exceeds the individual contributions of exonic and promoter conservation. We leverage this to train a simple and easily interpretable predictive model that outperforms other existing predictors and allows us to classify 1,760 genes-which are currently unascertained in gnomAD-as highly LoF intolerant or not. These predictions have the potential to aid in the interpretation of novel variants in the clinical setting. Moreover, our results reveal that high CpG density is not merely a generic feature of human promoters but is preferentially encountered at the promoters of the most selectively constrained genes, calling into question the prevailing view that CpG islands are not subject to selection.

    To obtain predictions for the course of the COVID-19 pandemic in Germany using the modified Bateman SIZ model and input variables based on the status quo in July 2020. To predict the effect of a change in t

    on the course of the pandemic. To evaluate the robustness and sensitivity of the model in response to a change in the input parameters.

    Start parameters for the modified Bateman SIZ model were obtained from observational data published by the Robert-Koch-Institute in Berlin for the period June 1 to July 13, 2020. The robustness and sensitivity of the model were determined by changing the input parameter for the doubling-time (t

    ) by ±5% and ±10%.

    The predictions show that small changes, ±5%, in the doubling-time, t

    for the rate of increase in the number of new infections, can have a major effect, both positive and negative, on the course of the pandemic. The model predicted that the number of persons infected with the virus would reach 1million within 8years. A 5% longer t

    would reduce the number of infected persons by ~75%.