Microcalorimetric bioassay for acute cellular toxicity is based on metabolicheat production from cultured cells. The biological response to toxicants is the inhibition of theheat production rate in cells, and toxicity...Microcalorimetric bioassay for acute cellular toxicity is based on metabolicheat production from cultured cells. The biological response to toxicants is the inhibition of theheat production rate in cells, and toxicity is expressed as the concentration of toxicant that is50% effective to this inhibition (IC_(50)). In this paper, the effect of Na_2SeO_3 on Bacillussubtilis growth was investigated at 37℃ by microcalorimetry. The relationship between growth rateconstants (k) and concentration of Na_2SeO_3(c) shows a logarithmic normal distribution, and IC_(50)is 20.3 μg/mL. All these thermokinetic information is readily obtained by an LKB 2277-204 heatconduction microcalorimeter. Microcalorimetry is a quantitative, inexpensive, and versatile methodfor toxicology research.展开更多
微量元素硒对炎性肠道疾病的免疫调控效应一直是研究关注的焦点.本文采用葡聚糖硫酸钠诱导的实验性小鼠急性溃疡性结肠炎模型,观察了亚硒酸钠(Na_(2)SeO_(3))灌胃对肠道局部及相关淋巴组织中的天然免疫细胞、适应性免疫B细胞、细胞毒性...微量元素硒对炎性肠道疾病的免疫调控效应一直是研究关注的焦点.本文采用葡聚糖硫酸钠诱导的实验性小鼠急性溃疡性结肠炎模型,观察了亚硒酸钠(Na_(2)SeO_(3))灌胃对肠道局部及相关淋巴组织中的天然免疫细胞、适应性免疫B细胞、细胞毒性T细胞(cytotoxic T cells,CTL)和辅助性T细胞(helper T cells,T_(H))的不同亚群T_(H)1,T_(H)2,调节性T细胞(regulatory T cells,T_(reg))及滤泡辅助性T细胞(follicular helper T cells,T_(FH))等的功能分化调控效应,并在体外观察了Na_(2)SeO_(3)对T_(FH)细胞分化的调控规律.结果显示,亚硒酸钠灌胃补硒可以加重急性肠炎,并促进T_(FH)细胞在肠道局部及肠周围淋巴组织浸润和B细胞免疫球蛋白A(immunoglobulin A,IgA)分泌.这为微量元素硒免疫调控肠道炎性疾病研究提供了依据,也为硒的临床应用研究提供了实验数据.展开更多
文摘Microcalorimetric bioassay for acute cellular toxicity is based on metabolicheat production from cultured cells. The biological response to toxicants is the inhibition of theheat production rate in cells, and toxicity is expressed as the concentration of toxicant that is50% effective to this inhibition (IC_(50)). In this paper, the effect of Na_2SeO_3 on Bacillussubtilis growth was investigated at 37℃ by microcalorimetry. The relationship between growth rateconstants (k) and concentration of Na_2SeO_3(c) shows a logarithmic normal distribution, and IC_(50)is 20.3 μg/mL. All these thermokinetic information is readily obtained by an LKB 2277-204 heatconduction microcalorimeter. Microcalorimetry is a quantitative, inexpensive, and versatile methodfor toxicology research.
文摘微量元素硒对炎性肠道疾病的免疫调控效应一直是研究关注的焦点.本文采用葡聚糖硫酸钠诱导的实验性小鼠急性溃疡性结肠炎模型,观察了亚硒酸钠(Na_(2)SeO_(3))灌胃对肠道局部及相关淋巴组织中的天然免疫细胞、适应性免疫B细胞、细胞毒性T细胞(cytotoxic T cells,CTL)和辅助性T细胞(helper T cells,T_(H))的不同亚群T_(H)1,T_(H)2,调节性T细胞(regulatory T cells,T_(reg))及滤泡辅助性T细胞(follicular helper T cells,T_(FH))等的功能分化调控效应,并在体外观察了Na_(2)SeO_(3)对T_(FH)细胞分化的调控规律.结果显示,亚硒酸钠灌胃补硒可以加重急性肠炎,并促进T_(FH)细胞在肠道局部及肠周围淋巴组织浸润和B细胞免疫球蛋白A(immunoglobulin A,IgA)分泌.这为微量元素硒免疫调控肠道炎性疾病研究提供了依据,也为硒的临床应用研究提供了实验数据.