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381.
FoxP3 + CD4 + regulatory T cells (Tregs) are important mediators of peripheral immune tolerance, acting via multiple mechanisms to suppress cellular immunity including antitumor responses. Although therapeutic strategies have been proposed to deplete Tregs in patients with breast cancer and other malignancies, dynamic changes in the Treg compartment as a function of stage and treatment of breast cancer remain poorly understood. Here, we evaluated peripheral blood CD4+ T cells and FoxP3+ CD4+ T cells from 45 patients with early or late stage breast cancer and compared percentages, absolute counts, and Treg function to those from healthy volunteers (HV) of comparable age. Patients having completed adjuvant chemotherapy and patients with metastatic cancer exhibited significantly lower absolute CD4 counts and significantly higher percentages of FoxP3+ CD4+ T cells. In contrast, the absolute counts of circulating FoxP3+ CD4+ T cells did not differ significantly among early stage patients, late stage patients, or HV. Functionally, FoxP3+ CD4+ T cells from all donor groups similarly expressed CTLA-4 and failed to secrete IFN-γ in response to stimulation. Thus, although Tregs comprise an increased percentage of circulating CD4+ T cells in patients with metastatic breast cancer and patients in remission after completing the adjuvant chemotherapy, the systemic Treg pool, as measured by absolute counts, appears relatively constant regardless of disease stage or treatment status. Total CD4+ T cell counts are not constant, however, suggesting that homeostatic mechanisms, or susceptibility to cytotoxic or malignant insults, fundamentally differ for regulatory and non-regulatory CD4+ T cells.  相似文献   
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Few studies in sub-Saharan Africa evaluate Institutional Review Boards (IRBs) capacity. The study aims to explore the composition of IRBs, training, and challenges experienced in the ethics review processes by members of research institutions and universities in Addis Ababa, Ethiopia. Our findings indicate that most IRBs members were trained on research ethics and good clinical practice. However, majority perceived the trainings as basic. IRB members faced several challenges including: investigators wanting rapid review; time pressure; investigators not following checklists; limited expertise in reviewing clinical trials, studies on genetics, and traditional medicine; lack of IRB offices for administrative work; competing tasks; limited staffing and the lack of a standardized review system. There is need for advanced training on research ethics to meet the evolving research needs. In addition, investments in IRBs are needed in terms of funding, and physical and human resources in Addis Ababa and Ethiopia in general.  相似文献   
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This paper presents an analysis of the attitudes of farmers towards a policy approach that combines the instrument of set-aside of farmland with agri-environmental measures under the Common Agricultural Policy (CAP) for achieving nature goals. One of the stated objectives of current agricultural and environmental policies is to give greater consideration to issues of nature conservation in agricultural landscapes. To fulfil this objective, there is an urgent need to develop approaches that, on the one hand, are capable of delivering tangible improvements in the ecological situation and nature conservation in agriculture and, on the other hand, are structured in such a way that farmers are willing to put them into practice. In addition, such approaches need to be economical and affordable for society. The Leibniz-Centre for Agricultural Landscape Research (ZALF) has developed the concept of ‘nature-conservation set-aside’, especially for landscapes that are under predominantly arable use. Conservation set-aside refers to parts of arable farmland especially well suited to nature conservation, which are mandatorily withdrawn from agricultural production (for those who claim payment) and on which ecologically valuable habitats are created through specific management activities. To determine what kind of problems might arise for farmers in the course of implementing this concept as an agri-environmental measure, a survey was carried out in four largely arable regions of Germany. The results of this survey show the attitudes of German farmers regarding set-aside farmland for nature conservation in regions dominated by arable farming, and they demonstrate which factors influence the implementation of conservation set-aside.  相似文献   
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During field surveys conducted in northern Jordan from June to November 2020, phytoplasma-like symptoms, including leaf yellowing/reddening and rolling, little leaf and witches' broom were observed in pomegranate. Disease incidence in 22 surveyed orchards ranged from 30% to 65%. Nested PCR-based amplification of 16S rRNA gene detected phytoplasmas in 17% of collected symptomatic pomegranate trees. Amplicon nucleotide sequence analyses allowed attributing the detected phytoplasmas to ‘Candidatus Phytoplasma solani’, ‘Ca. P. aurantifolia’, ‘Ca. P. asteris’ and ‘Ca. P. ulmi’. These phytoplasmas were found in plants showing specific symptoms and differentially distributed in the considered locations. Additionally, three cicadellids (Macrosteles sexnotatus, Cicadulina bipunctata and Psammotettix striatus) and two non-crop plants (Plantago major and Capsicum annuum) resulted hosting ‘Ca. P. asteris’ strains, and one cicadellid (Balclutha incisa) was carrying a ‘Ca. P. solani’ strain. A new pomegranate disease complex associated with multiple phytoplasmas, including ‘Ca. P. aurantifolia’ and ‘Ca. P. ulmi’, never reported before in this host plant, is described here. Moreover, preliminary indications are provided on its possible epidemiology in Jordan, involving two putative insect vectors (M. sexnotatus, B. incisa) first reported in the Country.  相似文献   
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Background  

Male Irs2 -/- mice develop fatal type 2 diabetes at 13-14 weeks. Defects in neuronal proliferation, pituitary development and photoreceptor cell survival manifest in Irs2 -/- mice. We identify retarded renal growth in male and female Irs2 -/- mice, independent of diabetes.  相似文献   
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