2,491 research outputs found

    Epigenetic regulation of nitric oxide synthase 2, inducible (Nos2) by NLRC4 inflammasomes involves PARP1 cleavage

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    Nitric oxide synthase 2, inducible (Nos2) expression is necessary for the microbicidal activity of macrophages. However, NOS2 over-activation causes multiple inflammatory disorders, suggesting a tight gene regulation is necessary. Using cytosolic flagellin as a model for inflammasome-dependent NOS2 activation, we discovered a surprising new role for NLRC4/caspase-1 axis in regulating chromatin accessibility of the Nos2 promoter. We found that activation of two independent mechanisms is necessary for NOS2 expression by cytosolic flagellin: caspase-1 and NF-kappa B activation. NF-kappa B activation was necessary, but not sufficient, for NOS2 expression. Conversely, caspase-1 was necessary for NOS2 expression, but dispensable for NF-kappa B activation, indicating that this protease acts downstream NF-kappa B activation. We demonstrated that epigenetic regulation of Nos2 by caspase-1 involves cleavage of the chromatin regulator PARP1 (also known as ARTD1) and chromatin accessibility of the NF-kappa B binding sites located at the Nos2 promoter. Remarkably, caspase-1-mediated Nos2 transcription and NO production contribute to the resistance of macrophages to Salmonella typhimurium infection. Our results uncover the molecular mechanism behind the constricted regulation of Nos2 expression and open new therapeutic opportunities based on epigenetic activities of caspase-1 against infectious and inflammatory diseases.Kanton of ZurichUniversity Research Priority Program (URPP) in Translational Cancer Biology at the University of ZurichSwiss National Science FoundationCancer Research SocietyCanadian Cancer SocietyNSERCOntario Institute for Cancer Research (OICR)province of OntarioPrincess Margaret Cancer FoundationUniversity of Toronto McLaughlin CentreFundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP - Brazil)Brazilian Research Council (CNPq-Brazil)CAPESINCTVUniv Fed Sao Paulo, Ctr Terapia Celular & Mol CTC Mol, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Ciencias Biol, Sao Paulo, BrazilUniv Sao Paulo, Inst Ciencias Biomed, Dept Microbiol, Sao Paulo, BrazilUniv Hlth Network, Princess Margaret Canc Ctr, Toronto, ON M5G 2M9, CanadaUniv Sao Paulo, Inst Ciencias Biomed, Sao Paulo & Inst Invest Imunol, Inst Nacl Ciencia Tecnol INCT 3, Sao Paulo, BrazilInst Nacl Ciencia Tecnol INCT III, Inst Invest Imunol, Sao Paulo, BrazilUniv Zurich, Dept Mol Mech Dis, Zurich, SwitzerlandUniv Toronto, Dept Med Biophys, Toronto, ON M5G 2M9, CanadaUniv Fed Sao Paulo, Ctr Terapia Celular & Mol CTC Mol, Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Ciencias Biol, Sao Paulo, BrazilSwiss National Science Foundation: 310030B_138667Cancer Research Society: CRS19092Cancer Research Society: CRS19091Canadian Cancer Society: CCSRI 703279Canadian Cancer Society CCSRI 703716NSERC: 489073University of Toronto McLaughlin Centre: MC-2015-02FAPESP: 2013/16010-5FAPESP: 2015/18003-1Web of Scienc

    Determining the best sectioning method and intestinal segment for morphometric analysis in broilers

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    Brazilian poultry production is very efficient and demands maximum broiler performance. Therefore, digestive system pathologies have a relevant role. Considering it is difficult to obtain consistent information on intestinal morphometric analysis, this study aimed at establishing essential and clear criteria for the collection of intestinal segments for morphometric analysis. Fifteen 13-d-old broilers were sacrificed and three intestinal segments were collected per bird. Two 3-cm long sections were obtained from each of the intestinal segments. Samples were collected open or closed. The closed samples were transversely, hemicylindrically, or longitudinally sectioned. Samples were processed and stained with hematoxylin and eosin. The number of microscopic fields in each section was counted. Villi presenting the base clearly embedded in the submucosa, no damage or folds, and simple columnar epithelium at the tip were considered adequate for measurements. These villi were counted in each sample. The results shows that hemicylindrical sections presented the highest number of observation fields, with an average of 9.76 fields. Jejunum samples were among the three highest average villi counts, with 18.23 in longitudinal sections and 15.61 in hemicylindrical sections. The results of the present study indicate that hemicylindrical sectioning and jejunal samples were, respectively, the best sectioning method and the best intestinal segment for the morphometric analysis of the intestines of broilers

    'Immunising' physicians against availability bias in diagnostic reasoning: A randomised controlled experiment

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    Background: Diagnostic errors have often been attributed to biases in physicians' reasoning. Interventions to 'immunise' physicians against bias have focused on improving reasoning processes and have largely failed. Objective: To investigate the effect of increasing physicians' relevant knowledge on their susceptibility to availability bias. Design, settings and participants: Three-phase multicentre randomised experiment with second-year internal medicine residents from eight teaching hospitals in Brazil. Interventions: Immunisation: Physicians diagnosed one of two sets of vignettes (either diseases associated with chronic diarrhoea or with jaundice) and compared/contrasted alternative diagnoses with feedback. Biasing phase (1 week later): Physicians were biased towards either inflammatory bowel disease or viral hepatitis. Diagnostic performance test: All physicians diagnosed three vignettes resembling inflammatory bowel disease, three resembling hepatitis (however, all with different diagnoses). Physicians who increased their knowledge of either chronic diarrhoea or jaundice 1 week earlier were expected to resist the bias attempt. Main outcome measurements: Diagnostic accuracy, measured by test score (range 0-1), computed for subjected-to-bias and not-subjected-to-bias vignettes diagnosed by immunised and not-immunised physicians. Results: Ninety-one residents participated in the experiment. Diagnostic accuracy differed on subjected-to-bias vignettes, with immunised physicians performing better than non-immunised physicians (0.40 vs 0.24; difference in accuracy 0.16 (95% CI 0.05 to 0.27); p=0.004), but not on not-subjected-to-bias vignettes (0.36 vs 0.41; difference -0.05 (95% CI -0.17 to 0.08); p=0.45). Bias only hampered non-immunised physicians, who performed worse on subjected-to-bias than not-subjected-to-bias vignettes (difference -0.17 (95% CI -0.28 to -0.05); p=0.005); immunised physicians' accuracy did not differ (p=0.56). Conclusions: An intervention directed at increasing knowledge of clinical findings that discriminate between similar-looking diseases decreased physicians' susceptibility to availability bias, reducing diagnostic errors, in a simulated setting. Future research needs to examine the degree to which the intervention benefits other disease clusters and performance in clinical practice. Trial registration number: 68745917.1.1001.0068

    Diversity of teachers’ conceptions related to environment and human rights. A survey in 24 countries

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    The environmental, social and economical dimensions of ESD include human rights as equality of all the human beings independently to their gender, ethnic group, religion or sexual orientation. To analyse teachers’ conceptions on environment and on human rights, and to identify eventual links between them and with controlled parameters, a large survey has been done in 24 countries (8 749 teachers). The data are submitted to multivariate analyses. In the less developed countries, the teachers’ conceptions are more anthropocentric, less awareness of the problem of the limit of resources in our planet, and less reticent to use GMO (genetically modified organisms). These teachers are more believing in God, more practicing religion, more for “a strong central power”, “against the separation between science and religion”. The priority of ESD in these countries is poverty and development, while it is to avoid wasting and excessive consumption in the most developed countries. The teachers with the most anthropocentric conceptions more agree with these propositions: “It is for biological reasons that women more often than men take care of housekeeping” and “Ethnic groups are genetically different and that is why some are superior to others”, and more disagree with: “Homosexual couples should have the same rights as heterosexual couples”. These points illustrate that some socio-cultural traditions can differ from values of ESD (the universal human rights).CIEC – FCT Research Unit 317

    Measurement of the t(t)over-bar production cross section in the dilepton channel in pp collisions at √s=8 TeV

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    The top-antitop quark (t (t) over bar) production cross section is measured in proton-proton collisions at root s = 8 TeV with the CMS experiment at the LHC, using a data sample corresponding to an integrated luminosity of 5.3 fb(-1). The measurement is performed by analysing events with a pair of electrons or muons, or one electron and one muon, and at least two jets, one of which is identified as originating from hadronisation of a bottom quark. The measured cross section is 239 +/- 2 (stat.) +/- 11 (syst.) +/- 6 (lum.) pb, for an assumed top-quark mass of 172.5 GeV, in agreement with the prediction of the standard model
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