In hepatic toxicity induced in rats by two injections of thioacetamide (TAA, 350 mg/kg with an interval of 8 hr), the action of quercetin was investigated. After 96 hr, TAA administration resulted in hepatic necrosis, significant increases in serum transaminase activity, and increases in hepatic lipoperoxidation. Thioacetamide-induced hepatotoxicity also showed changes in antioxidant enzymes in the liver of rats, with alterations in p-ERK 1/2 (phosphorylated extracellular-signal related kinase 1/2) as well as an imbalance between proapototic protein Bax and anti-apoptotic protein Bcl-2 expression. With administration of the flavonoid quercetin (50 mg/Kg i.p.) for four consecutive days following TAA, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activity were close to normal values in rats. Histological findings suggested that quercetin had a preventive effect on TAA-induced hepatic necrosis. Quercetin treatment caused significant decreases in lipid peroxide levels in the TAA-treated rats, with some changes in antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Quercetin also inhibited the change of the p-ERK1/2 by TAA and significantly prevented the increase in Bax/Bcl-2 ratio, thus preventing apoptosis. Findings indicate that quercetin may have a preventive effect on TAA-induced hepatotoxicity by modulating the oxidative stress parameters and apoptosis pathway.

Aim. This study aimed to assess the antioxidant activity of quercetin (Q) in an experimental model of cirrhosis induced by CCl4 inhalation. Materials and Methods. We used 25 male Wistar rats (250 g) that were divided into 3 groups: control (CO), CCl4, and CCl4 + Q. The rats were subjected to CCl4 inhalation (2x/week) for 16 weeks, and they received phenobarbital in their drinking water at a dose of 0.3 g/dL as a P450 enzyme inducer. Q (50 mg/Kg) was initiated intraperitoneally at 10 weeks of inhalation and lasted until the end of the experiment. Statistical analysis was by ANOVA Student Newman-Keuls (mean ± SEM), and differences were considered statistically significant when P < 0.05. Results. After treatment with quercetin, we observed an improvement in liver complications, decreased fibrosis, as analyzed by picrosirius for the quantification of collagen, and decreased levels of matrix metalloproteinase 2 (MMP-2) compared with the CCl4 group. It also reduced oxidative stress, as confirmed by the decrease of substances reacting to thiobarbituric acid (TBARS), the increased activity of antioxidant enzymes, and the reduced glutathione ratio and glutathione disulfide (GSH/GSSG). Conclusion. We suggest that the use of quercetin might be promising as an antioxidant therapy in liver fibrosis.

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The main goal of this study is to alert researchers who work with cell cultures for the risk of contamination by structures called nanobacteria (NB). NB are tiny structures with size varying from 80 to 500 nm, commonly occurring in clusters and producing a biofilm which contains carbonate or hydroxyl apatite. The most likely source of cell culture contamination by such organisms is serum used as supplement in culture media. The presence of NB leads to a progressive culture deterioration with accumulation of granules (probably phagocytized NB) in cytoplasmic vacuoles, an increasing number of dead cells in the supernatant and degeneration of cells that remained attached to the bottom of the vessel. NB can also be found in culture supernatants where they are found in clusters with variable size and displaying brownian movement. In this study, 19 cell lineages, 8 batches of sera and 1 batch of growth supplement from different sources were analyzed. Samples from sera were cultured in Eagle's Minimum Essential Medium (E-MEM) or incubated directly at 37ºC. Tests carried out to detect the presence of extracellular bacteria, Mycoplasma sp and viruses were all negative. Analysis by scanning electron microscopy (SEM) revealed tiny oval structures less than 500 nm in size, isolated or in small groups, in all material analyzed except in one fetal bovine serum batch.

Two chicken single-chain variable antibody fragments (scFv) designated scFv154 and scFv88, previously shown to react with either all or very virulent (vv) infectious bursal disease virus (IBDV) strains, respectively, were evaluated for use in an enzyme-linked immunosorbent assay (ELISA) for differentiation of vvIBDV. Specificity and sensitivity of the vvIBDV ELISA was assessed when scFv154 and scFv88 were expressed as soluble antibodies (sAb), phage antibodies (pAb) or hyper-phage antibodies (hpAb). The highest test sensitivity and specificity was obtained using hpAb154 to detect all IBDV and pAb88 to differentiate vvIBDV strains. Such an ELISA was eight to 16 times more sensitive for IBDV antigen detection than the mouse monoclonal antibody ELISA. Using field samples, the scFv ELISA was able to differentiate between flocks infected with vvIBDV and those infected with classical or variant IBDV. In one instance IBDV was detected in a flock found to be negative by the monoclonal antibody ELISA. The results showed that scFv can be utilized as highly specific and sensitive ELISA reagents for the detection and discrimination of avian pathogens.

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O presente estudo tem como objetivo analisar a percepção dos líderes sobre as práticas organizacionais em bancos públicos do Rio Grande do Sul, que geram o desenvolvimento de um ambiente intraempreendedor. A pesquisa foi desenvolvida com uma abordagem quantitativa e qualitativa. Líderes do setor bancário em atividade profissional no sul do Brasil responderam ao Instrumento de Avaliação do Empreendedorismo Corporativo, o CEAI (KURATKO; HORNSBY; COVIN, 2014), que foi complementado com duas perguntas abertas sobre a percepção de práticas que aprimoram ou fragilizam o intraempreendedorismo em seu ambiente de trabalho. Somando às informações qualitativas, também foi realizada uma entrevista com uma gerente de educação corporativa de uma das instituições pesquisadas. Os dados quantitativos foram tratados pela análise da estatística descritiva e inferencial, enquanto aos qualitativos aplicou-se a Análise de Conteúdo. Entre os principais resultados, destaca-se que as dimensões recompensa/reforço e discrição no trabalho foram as mais reconhecidas pelos líderes nas práticas organizacionais que aprimoram as atividades intraempreendedoras. O apoio da gestão foi reconhecido, bem como foram apontadas as dificuldades quando há esta falta de apoio. Os líderes percebem o empoderamento para o desenvolvimento de suas ideias com fragilidades nos fatores relacionados ao apoio e ao investimento institucional para a sua continuidade. As maiores oportunidades estão relacionadas à disponibilidade de tempo e aos limites organizacionais. O dinamismo organizacional bancário pode ser caracterizado por especificações de trabalho que inibem a flexibilidade necessária para aprimorar as práticas intraempreendedoras. O estudo apresenta limites em relação às características das instituições bancárias pesquisadas, podendo também ser tema para futuras pesquisas a investigação em bancos privados, além de um estudo mais aprofundado sobre a percepção dos liderados em relação ao tema do intraempreendedorismo. Palavras-Chave: Intraempreendedorismo. Setor bancário. Liderança.   Abstract: This study aims to analyze the perception of leaders about organizational practices in public banks in Rio Grande do Sul, which generate the development of an intrapreneurial environment. The research was developed with quantitative and qualitative approaches. Leaders of the banking sector in professional activity in southern Brazil responded to the Corporate Entrepreneurship Assessment Instrument, CEAI (KURATKO; HORNSBY; COVIN, 2014), which was complemented with two open questions about the perception of practices that improve and weaken intrapreneurship in your work environment. In addition to the qualitative information, an interview was also conducted with a corporate education manager from one of the institutions surveyed. Quantitative data were treated by the analysis of descriptive and inferential statistics, while qualitative data was applied by Content Analysis. Among the main results, it is highlighted that the dimensions reward / reinforcement and discretion at work were the most recognized by leaders in organizational practices that enhance intrapreneurial activities. Management support was acknowledged, but with an outstanding result. Leaders perceive the empowerment to develop their ideas with weaknesses in the factors related to support and institutional investment for their continuity. The greatest opportunities are related to the availability of time and organizational limits. Banking organizational dynamism can be characterized by job specifications that inhibit the flexibility needed to improve intrapreneurial practices. The study presents its limits in relation to the characteristics of the banking institutions surveyed, and may also be the subject for future research to investigate private banks and also a more in-depth study on the perception of those led in relation to the theme of intrapreneurship. Keywords: Intrapreneurship. Banking sector. Leadership.