426 research outputs found

    A Catalog of Coding Sequence Variations in Salivary Proteins’ Genes Occurring during Recent Human Evolution

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    Saliva houses over 2000 proteins and peptides with poorly clarified functions, including proline-rich proteins, statherin, P-B peptides, histatins, cystatins, and amylases. Their genes are poorly conserved across related species, reflecting an evolutionary adaptation. We searched the nucleotide substitutions fixed in these salivary proteins’ gene loci in modern humans compared with ancient hominins. We mapped 3472 sequence variants/nucleotide substitutions in coding, noncoding, and 5â€Č-3â€Č untranslated regions. Despite most of the detected variations being within noncoding regions, the frequency of coding variations was far higher than the general rate found throughout the genome. Among the various missense substitutions, specific substitutions detected in PRB1 and PRB2 genes were responsible for the introduction/abrogation of consensus sequences recognized by convertase enzymes that cleave the protein precursors. Overall, these changes that occurred during the recent human evolution might have generated novel functional features and/or different expression ratios among the various components of the salivary proteome. This may have influenced the homeostasis of the oral cavity environment, possibly conditioning the eating habits of modern humans. However, fixed nucleotide changes in modern humans represented only 7.3% of all the substitutions reported in this study, and no signs of evolutionary pressure or adaptative introgression from archaic hominins were found on the tested genes

    RET/PTC3 translocation in a rare hemorrhagic brain metastasis of papillary thyroid cancer post Chernobyl radiation affects vessels ultrastructure

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    Abstract Background Slow progression and good prognosis are the usual characteristics of papillary thyroid carcinoma (PTC). The presence of brain metastases (0.4–1.2%) is suggestive of a worse prognosis. RET/PTC rearrangements were particularly prevalent in PTCs developed after Chernobyl nuclear accident. Case description A 50-year-old woman born in Slovakia, exposed to radiation resulting from the accident at the Chernobyl nuclear power plant, affected since 2017 by papillary thyroid cancer and in therapy at our hospital, experimented cerebral hemorrhagic metastasis. Biopsy analyses revealed a RET/PTC3 rearrangement, so our aim was to find possible morphological relation between hemorrhagic metastasis and RET/PTC3 translocation. Results Immunohistochemical analysis showed diffuse and intense positivity for VEGF in endothelial cells of the neoplasm’ vascular network. Transmission electron microscopy images showed vessels with unorganized pattern and uneven diameters. In particular, metastasis endothelial cells (MECs) showed irregular shape and size, thickened cytoplasm and swelling of endoplasmic reticulum. MECs organized in irregular monolayers or multiple layers, surrounded by a thickened but unstructured extracellular matrix. Absence of strong junctional complexes among MECs resulted in a further weakened vessels wall. Conclusion RET/PTC3 translocation causes VEGF overexpression via STAT3 signaling cascade and the increased amount of VEGF adds to the greater amount of VEGFRs expressed by MECs. Our ultrastructural investigation show that this condition creates a massive growth of altered vessels prone to bleeding. The clinical significance of our study consists in alert oncologist and surgeons on possible arising of hemorrhagic brain metastases in patients with PTC and RET/PTC3 translocation exposed to ionizing radiation as people living in areas caught up in Chernobyl or Fukushima disasters

    Timing of surgery following SARS‐CoV‐2 infection: an international prospective cohort study

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    Peri-operative SARS-CoV-2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS-CoV-2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre-operative SARS-CoV-2 infection were compared with those without previous SARS-CoV-2 infection. The primary outcome measure was 30-day postoperative mortality. Logistic regression models were used to calculate adjusted 30-day mortality rates stratified by time from diagnosis of SARS-CoV-2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre-operative SARS-CoV-2 diagnosis. Adjusted 30-day mortality in patients without SARS-CoV-2 infection was 1.5% (95%CI 1.4–1.5). In patients with a pre-operative SARS-CoV-2 diagnosis, mortality was increased in patients having surgery within 0–2 weeks, 3–4 weeks and 5–6 weeks of the diagnosis (odds ratio (95%CI) 4.1% (3.3–4.8), 3.9% (2.6–5.1) and 3.6% (2.0–5.2), respectively). Surgery performed ≄ 7 weeks after SARS-CoV-2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5% (0.9– 2.1%)). After a ≄ 7 week delay in undertaking surgery following SARS-CoV-2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2–8.7) vs. 2.4% (95%CI 1.4–3.4) vs. 1.3% (95%CI 0.6–2.0%), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS-CoV-2 infection. Patients with ongoing symptoms ≄ 7 weeks from diagnosis may benefit from further delay
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