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The stress hormone cortisol (CORT) is slowly incorporated into the growing hair shaft of humans, nonhuman primates, and other mammals. We developed and validated a method for CORT extraction and analysis from rhesus monkey hair and subsequently adapted this method for use with human scalp hair. In contrast to CORT "point samples" obtained from plasma or saliva, hair CORT provides an integrated measure of hypothalamic-pituitary-adrenocortical (HPA) system activity, and thus physiological stress, during the period of hormone incorporation. Because human scalp hair grows at an average rate of 1 cm/month, CORT levels obtained from hair segments several cm in length can potentially serve as a biomarker of stress experienced over a number of months.In our method, each hair sample is first washed twice in isopropanol to remove any CORT from the outside of the hair shaft that has been deposited from sweat or sebum. After drying, the sample is ground to a fine powder to break up the hair''s protein matrix and increase the surface area for extraction. CORT from the interior of the hair shaft is extracted into methanol, the methanol is evaporated, and the extract is reconstituted in assay buffer. Extracted CORT, along with standards and quality controls, is then analyzed by means of a sensitive and specific commercially available enzyme immunoassay (EIA) kit. Readout from the EIA is converted to pg CORT per mg powdered hair weight. This method has been used in our laboratory to analyze hair CORT in humans, several species of macaque monkeys, marmosets, dogs, and polar bears. Many studies both from our lab and from other research groups have demonstrated the broad applicability of hair CORT for assessing chronic stress exposure in natural as well as laboratory settings.  相似文献   
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In vivo biomedical research is pivotal to translate in vitro findings into clinical advances. Small academic institutions with limited resources find it virtually impossible to build and maintain typical rodent facilities for research. Zebrafish research has been demonstrated to be a valuable alternative for in vivo research in pharmacology, physiology, development and genetic studies. This article demonstrates that a functional zebrafish facility can be built in an easy and affordable manner. We demonstrate that such a facility could be built in about one working day with minimal tools and expertise. The cost of the 27 1.8 L fish tank zebrafish facility constructed in this study was approximately $1,500. We estimate that the maintenance of an initial working 150 fish colony for 3 months is $1,000. This project involved students, who were introduced to aquaculturing of zebrafish for research proposes.  相似文献   
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《生物信息学》课程教学模式探讨   总被引:1,自引:0,他引:1       下载免费PDF全文
胡杨 《生物信息学》2018,16(2):72-75
在教学实践的基础上,结合生物信息学课程的学科特点,以及现代教育技术,就开设生物信息学课程的必要性及构建最合适的复合型教育模式展开了初步的探讨,为我国生物信息学课程的教学实施提供指导。随着时代的不断进步和发展,生物信息学的内涵也在不断扩大,包括生物信息学所涉及到的计算机基础知识、生物学基础知识、生物信息学研究领域、生物信息学应用领域等等。在生物信息学的教学实施过程中,将多个基础学科交叉融合是必备的,这不仅有助于增强学生对生物信息学科的了解,也对于学生在后续的生物信息学研究中起到了基石的作用。因此,如何将这些涉及范围广、涉及内容深的生物信息学基础课程恰当的传授给学生是教师们最需要考虑的问题,从而形成一套独特的教学体系,使生物信息学的教学工作更顺利,完整的进行下去。  相似文献   
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目的:研究存活素(Survivin)、碱性成纤维细胞生长因子(bFGF)、血管内皮生长因子(VEGF)在宫颈癌组织中的表达及其与临床病理特征的关系。方法:选择2015年1月-2017年12月期间武汉大学人民医院收治的宫颈癌患者95例为宫颈癌组,宫颈上皮内瘤变患者70例为宫颈上皮内瘤变组,取同期在我院进行治疗的宫颈炎患者50例纳入对照组。采集三组患者的宫颈组织标本,采用免疫组化SP法对各组织标本中的Survivin、bFGF、VEGF的阳性率、表达水平进行检测,并分析Survivin、bFGF、VEGF与宫颈癌临床病理特征的关系以及各指标表达水平的相关性。结果:宫颈癌组、宫颈上皮内瘤变组的Survivin、bFGF、VEGF的阳性表达率、表达水平均高于对照组,且宫颈癌组高于宫颈上皮内瘤变组(P0.05)。Survivin、bFGF、VEGF的表达与宫颈癌患者的年龄、病理类型、分化程度无关(P0.05),而与宫颈癌肿瘤的分期、淋巴结转移有关(P0.05)。Spearman相关性分析显示,Survivin、bFGF、VEGF三者间的表达水平两两呈正相关(P0.05)。结论:Survivin、bFGF、VEGF的表达水平与宫颈癌的发生、发展有密切关联,并且三种指标间呈明显的正相关性,可能对于宫颈癌肿瘤组织的浸润、转移、分期发挥协同作用。  相似文献   
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Although immunotherapy continues to demonstrate efficacy in a variety of refractory cancers, currently, no any immunotherapeutic strategy is clinically used for gastric cancer (GC) except its microsatellite instable subtype. Thus, it is important to identify molecular biomarkers for predicting the responders to GC immunotherapy. TP53 mutations frequently occur in GC and are associated with unfavorable clinical outcomes in GC. We performed a comprehensive characterization of the associations between TP53 mutations and immune activities in GC based on two large-scale GC cancer genomics data. We compared expression and enrichment levels of 787 immune-related genes and 23 immune gene-sets among TP53-mutated GCs, TP53‐wildtype GCs, and normal tissue, and explored the correlations between p53-mediated pathways and immune activities in GC. Strikingly, almost all analyzed immune gene-sets were significantly downregulated in enrichment levels in TP53-mutated GCs compared to TP53‐wildtype GCs. These less active immune pathways and cell types in TP53-mutated GCs included 15 immune cell types and function, tumor-infiltrating lymphocytes, regulatory T cells, immune checkpoint, cytokine and cytokine receptor, human leukocyte antigen, pro‐inflammatory, and parainflammation. Moreover, we identified a number of p53-mediated pathways and proteins that were significantly associated with immune activities in GC. Furthermore, we demonstrated that the TP53 mutation itself could result in the depressed immune activities in GC and other cancer types. We revealed that chromosomal instability was an important mechanism for the depressed tumor immunity in TP53-mutated cancers. Finally, we showed that immune cell infiltration and immune activities were likely positively associated with survival prognosis in GC. Our findings suggest that p53 may play an important role in activating tumor immunity in GC and other cancer types and that the TP53 mutation status could be useful in stratifying cancer patients responsive to a certain immunotherapy.  相似文献   
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An improved, forthright, and highly efficient one-pot synthesis of a wide range of pharmaceutically exciting diverse kind of functionalized 2-amino-3-cyano-4H-pyrans and especially bis-pyrans compounds is developed using piperazine as a low-cost and environmentally benign commercially available basic catalyst in aqueous media. The attractive features of this process are simple procedure, short reaction times, high yields, no column chromatographic separation and commercial availability and recyclability of the catalyst. Also, piperazine can catalyze the synthesis of the target compounds on a larger scale. Furthermore, rational mechanism was suggested via GC-Mass analysis of the trapped intermediates.  相似文献   
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