999 resultados para Suppressive environment


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There is a molecular crosstalk between the trophoblast and maternal immune cells of bovine endometrium. The uterine cells are able to secrete cytokine/chemokines to either induce a suppressive environment for establishment of the pregnancy or to recruit immune cells to the endometrium to fight infections. Despite morphological differences between women and cows, mechanisms for immune tolerance during pregnancy seem to be conserved. Mechanisms for uterine immunesuppression in the cow include: reduced expression of major histocompatability proteins by the trophoblast; recruitment of macrophages to the pregnant endometrium; and modulation of immune-related genes in response to the presence of the conceptus. Recently, an eGFP transgenic cloned embryo model developed by our group showed that there is modulation of foetal proteins expressed at the site of syncytium formation, suggesting that foetal cell can regulate not only by the secretion of specific factors such as interferon-tau, but also by regulating their own protein expression to avoid excessive maternal recognition by the local immune system. Furthermore, foetal DNA can be detected in the maternal circulation; this may reflect the occurrence of an invasion of trophoblast cells and/or their fragment beyond the uterine basement membrane in the cow. In fact, the newly description of exosome release by the trophoblast cell suggests that could be a new fashion of maternal-foetal communication at the placental barrier. Additionally, recent global transcriptome studies on bovine endometrium suggested that the immune system is aware, from an immunological point of view, of the presence of the foetus in the cow during early pregnancy.

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In Brazil, as in other sugar cane (Saccharum spp.) producing countries, varieties and clones have been continuously developed and tested in order to obtain varieties better adapted to changes in climate, soils and management, seeking a better performance in soils and climates of low agricultural suitability for the culture. In this study, the initial vegetative growth and performance of five sugar cane clones (CT96-3095, CT95-3079, CT95-1425, CT96-3024, CT92-1882) and two varieties (SP81-3250 and SP91-1049) were evaluated in an environment characterized by soils of low fertility and sandy texture. The experiment was carried out in a randomized design with seven treatments, consisting of the two sugar cane varieties and five clones. The plots contained six 15 meters sugar cane rows with a line spacing of 1.50 m. The average tiller number, tiller leaf area, vegetative cover, shoot biomass and rate of cover between rows of sugarcane were determined through six assessments in the first half of 2008. At the end of the evaluation (116 days after planting) the results showed that the clones (CT96-3095, CT95-3079, CT95-1425, CT96-3024, CT92-1882) were not significantly superior to the two considered varieties (SP81-3250 and SP91-1049).

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There is a molecular crosstalk between the trophoblast and maternal immune cells of bovine endometrium. The uterine cells are able to secrete cytokine/chemokines to either induce a suppressive environment for establishment of the pregnancy or to recruit immune cells to the endometrium to fight infections. Despite morphological differences between women and cows, mechanisms for immune tolerance during pregnancy seem to be conserved. Mechanisms for uterine immunesuppression in the cow include: reduced expression of major histocompatability proteins by the trophoblast; recruitment of macrophages to the pregnant endometrium; and modulation of immune-related genes in response to the presence of the conceptus. Recently, an eGFP transgenic cloned embryo model developed by our group showed that there is modulation of foetal proteins expressed at the site of syncytium formation, suggesting that foetal cell can regulate not only by the secretion of specific factors such as interferon-tau, but also by regulating their own protein expression to avoid excessive maternal recognition by the local immune system. Furthermore, foetal DNA can be detected in the maternal circulation; this may reflect the occurrence of an invasion of trophoblast cells and/or their fragment beyond the uterine basement membrane in the cow. In fact, the newly description of exosome release by the trophoblast cell suggests that could be a new fashion of maternal-foetal communication at the placental barrier. Additionally, recent global transcriptome studies on bovine endometrium suggested that the immune system is aware, from an immunological point of view, of the presence of the foetus in the cow during early pregnancy.

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Several improvements in ovarian cancer treatment have been achieved in recent years, both in surgery and in combination chemotherapy with targeting. However, ovarian tumors remain the women's cancers with highest mortality rates. In this scenario, a pivotal role has been endorsed to the immunological environment and to the immunological mechanisms involved in ovarian cancer behavior. Recent evidence suggests a loss of the critical balance between immune-activating and immune-suppressing mechanisms when oncogenesis and cancer progression occur. Ovarian cancer generates a mechanism to escape the immune system by producing a highly suppressive environment. Immune-activated tumor infiltrating lymphocytes (TILs) in ovarian tumor tissue testify that the immune system is the trigger in this neoplasm. The TIL mileau has been demonstrated to be associated with better prognosis, more chemosensitivity, and more cases of optimal residual tumor achieved during primary cytoreduction. Nowadays, scientists are focusing attention on new immunologically effective tumor biomarkers in order to optimize selection of patients for recruitment in clinical trials and to identify relationships of these biomarkers with responses to immunotherapeutics. Assessing this point of view, TILs might be considered as a potent predictive immunotherapy biomarker.

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Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis of horses caused by bites of Culicoides spp. IBH does not occur in Iceland where Culicoides are absent. However, following importation into continental Europe where Culicoides are present, >or=50% of Icelandic horses (1st generation) develop IBH but suppressive effect on IL-4 production mediated by IL-10 and TGF-beta1.

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This paper reports on the experiences of an extracurricular program in English language learning (ELL) that was implemented in an institute of technology in the hinterland of the People's Republic of China (PRC). Following the guidelines set out in an impact study of the reform of curriculum change in Hong Kong (Adamson & Morris, 2000), this study takes account of the context of the particular socio-cultural and political environment in which the research program takes place. Three distinct phases emerged in the career of the extracurricular program - the establishment of the program; successful implementation; and the decline. The study identifies three key factors that shaped these phases: teacher motivation; student motivation and its various influences; and available resources (including collegial and administrative support). The findings suggest that of the key factors impacting on the ELL extracurriculum, student motivation was the most influential.

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