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31.
Thymic CD4(+)CD25(+) cells from ducks were characterized for mammalian T regulatory cells' suppressive and cytokine production properties. The cross reactivity of anti-chicken CD25 monoclonal antibody with duck CD25 was confirmed by evaluating Concanavalin-A-stimulated CD25 upregulation in splenocytes. CD4(+)CD25(+) cells were detectable in the thymus, spleen, cecal tonsil, and lung (airsacs), but not in the bursa. Duck CD4(+)CD25(+) cells had approximately nine-fold higher IL-10 mRNA, 12-fold higher TGF-β, 16-fold higher CTLA-4, and nine-fold higher LAG-3 mRNA amounts than thymic CD4(+)CD25(-) cells. Thymic CD4(+)CD25(+) cells had no detectable levels of IL-2 mRNA. Duck CD4(+)CD25(+) cells had a three-fold higher IL-10 mRNA amount than chicken CD4(+)CD25(+) cells. Duck CD4(+)CD25(+) cells were anergic in vitro. Duck CD4(+)CD25(+) cells suppressed naive cell proliferation at effector: responder cell ratios above 0.5:1 in both contact-dependent and -independent pathways. It could be concluded that thymic CD4(+)CD25(+) cells in ducks are most likely the counterpart of mammalian T regulatory cells.  相似文献   
32.
Serum lipid levels were measured in 66 healthy sloth bears (Melursus ursinus ursinus) living under semicaptive conditions with access to natural food resources in the Bannerghatta Biological Park (Karnataka, India), a portion of their native habitat range in the Indian peninsula. Total cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, and low-density lipoprotein cholesterol levels were analyzed. The effects of age, body weight, and season on these lipid parameters were statistically evaluated. There were no correlations between age and any of the serum lipid parameters analyzed. Positive correlations of body weight to both triglyceride and HDL cholesterol levels in these bears were identified. In addition, seasonal trends in physiological serum lipid values, potentially due to variations in the sloth bear diet, were identified. Serum triglyceride levels were higher during postmonsoon season and cholesterol levels were higher during winter compared to other seasons. Serum lipid values obtained from sloth bears in this study were also compared to previously published data on other members of the family Ursidae. This is the first report of serum lipid values as a reference for sloth bears. These values can be used as sensitive predictors of overall health and nutritional status to aid in the captive management and feeding of these bears.  相似文献   
33.
The objective of this study was to identify the effect of in vitro lipopolysaccharide (LPS) treatment on regulatory T cells (Tregs) from chickens. Tregs had approximately 30-fold higher TLR 2-type 2 and six-fold higher TLR 4 mRNA content than CD4+CD25- cells. Tregs were treated with either 0 or 1 μg/ml LPS for 0, 2, and 4d. LPS treatment increased the IL-2 mRNA amount in Tregs at 2 and 4d post-LPS treatment. LPS treatment increased the IL-10 mRNA amount in Tregs at 4d post-LPS treatment. The total live cell numbers were approximately two-fold higher at 2d and three-fold higher at 4d in the 1 μg/ml LPS-treated groups than in the 0 μg LPS-treated controls. LPS treatment abrogated suppressive properties of Tregs at 2d post-LPS treatment. At 4d post-LPS treatment, Tregs became supersuppressive. In conclusion, chicken Tregs are differentially activated to facilitate immune response during the early stage of inflammation and to facilitate immune suppression at a later stage of inflammation.  相似文献   
34.
Mechanisms that direct reprogramming of differentiated somatic cells to induced pluripotent stem cells (iPSCs), albeit incomplete in understanding, are highly conserved across all mammalian species studied. Equally, proof of principle that iPSCs can be derived from domestic cattle has been reported in several publications. In our efforts to derive and study bovine iPSCs, we encountered inadequacy of methods to generate, sustain, and characterize these cells. Our results suggest that iPSC protocols optimized for mouse and human somatic cells do not effectively translate to bovine somatic cells, which show some refractoriness to reprogramming that also affects sustenance. Moreover, methods that enhance reprogramming efficiency in mouse and human cells had no effect on improving bovine cell reprogramming. Although use of retroviral vectors coding for bovine OCT4, SOX2, KLF4, cMYC, and NANOG appeared to produce consistent iPSC‐like cells from both fibroblasts and cells from the Wharton's jelly, these colonies could not be sustained. Use of bovine genes could successfully reprogram both mouse and human cells. These findings indicated either incomplete reprogramming and/or discordant/inadequate culture conditions for bovine pluripotent stem cells. Therefore, additional studies that advance core knowledge of bovine pluripotency are necessary before any anticipated iPSC‐driven bovine technologies can be realized.  相似文献   
35.
An increased understanding of the importance of forest diversity for ecosystem services such as medicine, wood, climate control, etc., has lead to greater interest in the study of forests. This study aims to analyze the diversity, composition, and distribution pattern of tree species in Pachamalai Reserve Forest in the Eastern Ghats of Tamil Nadu State. Data were collected in the quadrant method, where 10 × 10 m2 plots at different altitudes from 230 to 930 m with 50-m regular intervals were plotted. A total of 73 tree species belonging to 35 families with the density of 1,372 individuals were enumerated from 3 ha. Overall, the most dominant tree species family was Fabaceae (21 species). The highest number in terms of density of tree species was observed for Pongamia pinnata and the most dominant on the basis of basal area was Tamarindus indica. The species inventory was calculated by Shannon-Weiner index (3.916), Simpson index (0.0206), and Margalef index (9.9667). With the increasing altitudinal gradient, the maximum species richness was observed in the middle elevation zone from 580 to 780 m. The results from the study could be helpful for monitoring and sustaining the forest resources, and important in preventing the loss of biodiversity and mitigating climate change.  相似文献   
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