目的:建立核磁共振一维碳谱定性鉴别低分子肝素类型的方法。方法:一维13C-NMR实验在装配5 mm BBO探头的Bruker Ascend-500核磁共振谱仪上采集。采样时间1.1s;弛豫时间1s;测量温度40℃;谱宽δ(ppm)236。结果:比较不同类型低分子量肝素标...目的:建立核磁共振一维碳谱定性鉴别低分子肝素类型的方法。方法:一维13C-NMR实验在装配5 mm BBO探头的Bruker Ascend-500核磁共振谱仪上采集。采样时间1.1s;弛豫时间1s;测量温度40℃;谱宽δ(ppm)236。结果:比较不同类型低分子量肝素标准品的碳谱精细结构信息发现,不同类型的低分子量肝素都有其特征的碳谱信号,因此可以通过碳谱特征信号对低分子量肝素进行区分。结论:核磁共振一维碳谱定性鉴别低分子肝素的方法专属性强,简单方便,是鉴别低分子量肝素较好的方法。展开更多
AIM： TO study if T-cell activation related to portasystemic shunting causes osteoclast-mediated bone loss through RANKL-dependent pathways. We also investigated if T-cell inhibition using rapamycin would protect agai...AIM： TO study if T-cell activation related to portasystemic shunting causes osteoclast-mediated bone loss through RANKL-dependent pathways. We also investigated if T-cell inhibition using rapamycin would protect against bone loss in rats. METHODS： Portasystemic shunting was performed in male Sprague-Dawley rats and rapamycin 0.1 mg/kg was administered for 15 wk by gavage. Rats received powderized chow and supplemental feeds to prevent the effects of malnutrition on bone composition. Weight gain and growth was restored after surgery in shunted animals. At termination, biochemical parameters of bone turnover and quantitative bone histology were assessed. Markers of T-cell activation, inflammatory cytokine production, and RANKL-dependent pathways were measured. In addition, the roles of IGF-1 and hypogonadism were investigated. RESULTS： Portasystemic shunting caused low turnover osteoporosis that was RANKL independent. Bone resorbing cytokine levels, including IL-1, IL-6 and TNFα, were not increased in serum and TNFα and RANKL expression were not upregulated in PBMC. Portasystemic shunting increased the circulating CD8＋ T-cell population. Rapamycin decreased the circulating CD8＋ T-cell population, increased CD8＋ CD25＋ T-regulatory cell population and improved all parameters of bone turnover. CONCLUSION： Osteoporosis caused by portasystemic shunting may be partially ameliorated by rapamycin in the rat model of hepatic osteodystrophy.展开更多
文摘目的:建立核磁共振一维碳谱定性鉴别低分子肝素类型的方法。方法:一维13C-NMR实验在装配5 mm BBO探头的Bruker Ascend-500核磁共振谱仪上采集。采样时间1.1s;弛豫时间1s;测量温度40℃;谱宽δ(ppm)236。结果:比较不同类型低分子量肝素标准品的碳谱精细结构信息发现,不同类型的低分子量肝素都有其特征的碳谱信号,因此可以通过碳谱特征信号对低分子量肝素进行区分。结论:核磁共振一维碳谱定性鉴别低分子肝素的方法专属性强,简单方便,是鉴别低分子量肝素较好的方法。
文摘AIM： TO study if T-cell activation related to portasystemic shunting causes osteoclast-mediated bone loss through RANKL-dependent pathways. We also investigated if T-cell inhibition using rapamycin would protect against bone loss in rats. METHODS： Portasystemic shunting was performed in male Sprague-Dawley rats and rapamycin 0.1 mg/kg was administered for 15 wk by gavage. Rats received powderized chow and supplemental feeds to prevent the effects of malnutrition on bone composition. Weight gain and growth was restored after surgery in shunted animals. At termination, biochemical parameters of bone turnover and quantitative bone histology were assessed. Markers of T-cell activation, inflammatory cytokine production, and RANKL-dependent pathways were measured. In addition, the roles of IGF-1 and hypogonadism were investigated. RESULTS： Portasystemic shunting caused low turnover osteoporosis that was RANKL independent. Bone resorbing cytokine levels, including IL-1, IL-6 and TNFα, were not increased in serum and TNFα and RANKL expression were not upregulated in PBMC. Portasystemic shunting increased the circulating CD8＋ T-cell population. Rapamycin decreased the circulating CD8＋ T-cell population, increased CD8＋ CD25＋ T-regulatory cell population and improved all parameters of bone turnover. CONCLUSION： Osteoporosis caused by portasystemic shunting may be partially ameliorated by rapamycin in the rat model of hepatic osteodystrophy.
