Search for H→γγ produced in association with top quarks and constraints on the Yukawa coupling between the top quark and the Higgs boson using data taken at 7 TeV and 8 TeV with the ATLAS detector

A search is performed for Higgs bosons produced in association with top quarks using the diphoton decay mode of the Higgs boson. Selection requirements are optimized separately for leptonic and fully hadronic final states from the top quark decays. The dataset used corresponds to an integrated luminosity of 4.5 fb−14.5 fb−1 of proton–proton collisions at a center-of-mass energy of 7 TeV and 20.3 fb−1 at 8 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. No significant excess over the background prediction is observed and upper limits are set on the tt¯H production cross section. The observed exclusion upper limit at 95% confidence level is 6.7 times the predicted Standard Model cross section value. In addition, limits are set on the strength of the Yukawa coupling between the top quark and the Higgs boson, taking into account the dependence of the tt¯H and tH cross sections as well as the H→γγ branching fraction on the Yukawa coupling. Lower and upper limits at 95% confidence level are set at −1.3 and +8.0 times the Yukawa coupling strength in the Standard Model

Contributions of common genetic variants to risk of schizophrenia among individuals of African and Latino ancestry

Schizophrenia is a common, chronic and debilitating neuropsychiatric syndrome affecting tens of millions of individuals worldwide. While rare genetic variants play a role in the etiology of schizophrenia, most of the currently explained liability is within common variation, suggesting that variation predating the human diaspora out of Africa harbors a large fraction of the common variant attributable heritability. However, common variant association studies in schizophrenia have concentrated mainly on cohorts of European descent. We describe genome-wide association studies of 6152 cases and 3918 controls of admixed African ancestry, and of 1234 cases and 3090 controls of Latino ancestry, representing the largest such study in these populations to date. Combining results from the samples with African ancestry with summary statistics from the Psychiatric Genomics Consortium (PGC) study of schizophrenia yielded seven newly genome-wide significant loci, and we identified an additional eight loci by incorporating the results from samples with Latino ancestry. Leveraging population differences in patterns of linkage disequilibrium, we achieve improved fine-mapping resolution at 22 previously reported and 4 newly significant loci. Polygenic risk score profiling revealed improved prediction based on trans-ancestry meta-analysis results for admixed African (Nagelkerke’s R2 = 0.032; liability R2 = 0.017; P < 10−52), Latino (Nagelkerke’s R2 = 0.089; liability R2 = 0.021; P < 10−58), and European individuals (Nagelkerke’s R2 = 0.089; liability R2 = 0.037; P < 10−113), further highlighting the advantages of incorporating data from diverse human populations

Cytokine-induced beta-galactoside alpha-2,6-sialyltransferase in human endothelial cells mediates alpha 2,6-sialylation of adhesion molecules and CD22 ligands.

Sialic acids decorating blood and cell surface proteins can play important roles in various biological processes. The inflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-1, as well as bacterial lipopolysaccharide, can activate vascular endothelium, increasing expression of several surface glycoproteins. Here we show that treatment of cultured human endothelial cells (HEC) with TNF-alpha, interleukin-1, or lipopolysaccharide causes increased expression of the enzyme beta-galactoside alpha-2,6-sialytransferase (alpha 2-6STN). TNF-alpha was most effective, inducing a 3.5-fold enhancement of cell-associated sialytransferase activity by 72 h. In addition, activated HEC secreted a large portion of the induced sialyltransferase activity into the medium. Analysis of labeled HEC showed both a relative and an absolute increase of alpha 2,6-linked sialic acid on N-linked oligosaccharides after TNF-alpha stimulation. This coincided with increased expression of endothelial glycoproteins bearing N-linked glycans with alpha 2,6-linked sialic acid detected by the lectin Sambucus nigra agglutinin. The cytokine-inducible endothelial cell adhesion molecules E-selectin, ICAM-1, and VCAM-1 are among these glycoprotein substrates for alpha 2-6STN. These changes also correlated with a substantial increase in binding sites for CD22 beta, a mammalian lectin known to recognize oligosaccharides carrying multiple copies of alpha 2,6-linked sialic acid. Northern analysis revealed increased levels of mRNA encoding alpha 2-6STN. Thus, activation of endothelial cells during inflammatory and immunological processes may induce alpha 2-6STN, which can participate in sialylation of other activation-dependent molecules

Aplicação da técnica de PCR na detecção de Yersinia enterocolitica em suínos abatidos sem inspeção PCR technique application in Yersinia enterocolitica detection in non-inspected swine

Avaliou-se a contaminação de carcaças e tonsilas de suínos por Y. enterocolitica em estabelecimentos de abate não inspecionados, comparando a pesquisa microbiológica convencional com a técnica da reação em cadeia de polimerase (PCR) e o tipo de amostra analisada (de tonsila ou de carcaça), como subsídio ao monitoramento microbiano em sistemas de análise de perigos e pontos críticos de controle. Calcularam-se os custos dos dois testes. Não se detectou Y. enterocolitica pela técnica microbiológica convencional, mas, pela técnica de PCR foi possível detectar a bactéria em 40% das carcaças e em 43% das tonsilas, incluindo cepas patogênicas nas tonsilas. Não houve diferença entre os resultados positivos para as amostras de tonsilas e esfregaços de superfície das carcaças. A PCR apresentou-se como uma alternativa na detecção do agente e uma técnica aparentemente mais eficaz, econômica e rápida. Os resultados indicam a PCR como um importante recurso para o controle de qualidade da carne suína.The contamination of swine carcasses and tonsils by Yersinia enterocolitica in slaughterhouses without inspection was evaluated. The conventional microbiological analysis was compared with the PCR technique of carcass or tonsil swabs, as a subsidy to the microbiological evaluation in the HACCP system. The costs of the two techniques were also calculated. Y. enterocolitica was not detected by the conventional microbiological analysis. Using the PCR, it was possible to detect this bacterium in carcass (40%) and tonsil (43%) samples. There was no difference between the positive results for the carcass and tonsil samples. The PCR showed to be a more effective, fast and economic alternative for the Y. enterocolitica detection, as compared to the conventional microbiological analysis