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Mirelle Lomar Viana Rosana das Graças Carvalho dos Santos Simone de Vasconcelos Generoso Jacques Robert Nicoli Flaviano dos Santos Martins José Augusto Nogueira-Machado Rosa Maria Esteves Arantes Maria Isabel Toulson Davisson Correia Valbert Nascimento Cardoso 《Amino acids》2013,45(5):1089-1096
This study investigated the nitric oxide (NO) role as a mediator of arginine on bacterial translocation (BT) and gut damage in mice after intestinal obstruction (IO). The effects of pretreatment with arginine with or without NO inhibition on the systemic and local immunological response were also assessed. Mice were categorized into four groups. Group ARG received chow containing 2 % arginine, while group ARG + l-NAME received the same diet plus l-NAME (N-nitro-l-arginine methyl ester) by gavage. The IO and Sham groups were fed standard chow. After 7 days, animals were gavaged with radiolabeled Escherichia coli, anesthetized and subjected to IO, except the Sham group. Animals were euthanized after 18 h, and BT was evaluated in the mesenteric lymph nodes, blood, liver, spleen and lungs. In another experiment, the intestinal injury was assessed regarding intestinal permeability and ileum histological analyses. Intestinal secretory immunoglobulin A (sIgA) levels, serum IFN-γ and IL-10 cytokines were assessed. Arginine reduced BT, but NO inhibition enhanced BT compared with the ARG group (p < 0.05). Intestinal permeability in the ARG and ARG + l-NAME groups was similar but decreased when compared with the IO group (p < 0.05). Histological preservation was observed. Arginine treatment increased IL-10 and sIgA levels when compared with the Sham and IO groups (p < 0.05). The cytokines and sIgA concentrations were similar in the ARG + l-NAME and Sham groups. Arginine appeared to reduce BT and its effects on the modulation of cytokines and secretory IgA in mice after IO are mediated by NO production. 相似文献
73.
Mário S. Diniz Hugo M. Santos Pedro M. Costa Isabel Peres Maria H. Costa José L. Capelo 《Biomarkers》2013,18(6):589-598
The main objective of this work was to evaluate arsenic effects on metallothionein (MT) induction by exposing a freshwater Asiatic clam (Corbicula fluminea) to different concentrations of this metalloid. The presence of MT-like proteins was detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis and compared with a standard rabbit MT. In addition, the polarographic response showed good correspondence between standard MT and MT-like curves from C. fluminea, allowing MT quantification. The results show that clams exposed to different concentrations of arsenic are able to induce significant levels of MTs. Although variability was found in MT induction, significant differences in MT levels were found after 28 days of exposure in all treatments in comparison with the controls, suggesting that exposure to arsenic induced MT-like proteins in C. fluminea. 相似文献
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The diet of the gracile mouse opossum Gracilinanus microtarsus was studied in a cerrado remnant in south-eastern Brazil through the analysis of faeces sampled from adult individuals. Patterns of food resource consumption were assessed using the statistics of per cent occurrence. Intrapopulation variation in the number of food items detected in faeces as a function of relevant factors was inferred using generalized linear models. The latter statistical formalism also allowed variation in the number of food items detected in faeces to be interpreted in terms of rate ratios among levels of significant factors. Insects, spiders, snails and fruits were detected in the faeces of G. microtarsus , with insects, particularly termites, beetles and ants, being the most frequently detected food resource. These food resources were consumed in proportion to their relative abundance in the cerrado, suggesting that G . microtarsus is an opportunistic forager feeding primarily on insects. The generalized linear model identified sex, season and food resource as significant factors affecting the number of food items detected in faeces, as well as interactions between sex and season and season and food resource. Rate ratios calculated between sexes within seasons showed that the number of food items detected in the faeces of males was larger than that detected in the faeces of females in the warm-wet and cool-dry seasons. Rate ratios calculated between seasons within sexes showed different trends in the number of food items detected in faeces for each significant food resource. It is suggested that differences in the number of food items detected in faeces between sexes within season and between seasons within sexes are related to energetic requirements associated with reproduction. 相似文献
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Production of moss‐dominated biocrusts to enhance the stability and function of the margins of artificial water bodies 下载免费PDF全文
Ricardo Cruz de Carvalho Patrícia dos Santos Cristina Branquinho 《Restoration Ecology》2018,26(3):419-421
Margins of water reservoirs associated with dams can have high‐frequency tides, promoting soil erosion and nutrient leaching. We propose the use of biocrusts for restoration and ecological engineering purposes, due to their poikilohydric character, to stabilize reservoir margins. We promoted biocrust growth under controlled conditions, testing two types of substrate: native sand and organic substrate. After 2 months, biocrusts grew on organic substrate covering almost all the area, but not on native sand. This fast and easy nature‐based solution for soil stabilization can be used as an environmental engineering tool in highly degraded sites. 相似文献
79.
Kenyi Saito-Diaz Hassina Benchabane Ajit Tiwari Ai Tian Bin Li Joshua J. Thompson Annastasia S. Hyde Leah M. Sawyer Jeanne N. Jodoin Eduardo Santos Laura A. Lee Robert J. Coffey R. Daniel Beauchamp Christopher S. Williams Anne K. Kenworthy David J. Robbins Yashi Ahmed Ethan Lee 《Developmental cell》2018,44(5):566-581.e8
80.
Fleur E van de Geijn Manfred Wuhrer Maurice HJ Selman Sten P Willemsen Ya?l A de Man André M Deelder Johanna MW Hazes Radboud JEM Dolhain 《Arthritis research & therapy》2009,11(6):R193