顶空气相色谱法测定盐酸依匹斯汀中溶剂残留

建立顶空气相色谱法分析盐酸依匹斯汀中溶剂残留.采用DB-1大口径毛细管柱,以正丙醇为内标进行定量.甲醇、乙醚、三氯甲烷、四氢呋喃的线性范围分别为7.9 ～ 317.0μg·ml-1 (r=0.9996),0.7～35.5μg·ml-1(r=0.9998),1.5～73.5μg·ml-1 (r=0.9992),0.9～44.4μg·ml-1(r=0.9994),回收率分别为101.64%,97.18%,99.32%,101.12%,RSD分别为1.97%,1.10%,2.40%,0.84%.本方法简单、准确、灵敏度高、重现性好.     

头孢拉定及其胶囊剂中有关物质检查方法的探讨

目的:对头孢拉定原料及制剂的有关物质检查方法进行探讨.方法:对现行版药典中的头孢拉定及其制剂的有关物质检查方法进行比较和实验观察.结论:可用<中国药典>中检查拉定原料有关物质的方法对胶囊剂进行检查,并认为有必要增加此项目.同时建议对原料有关物质检查项中杂质对照的点样方法进行修改.     

Effect of inflammation on endothelial cells induced by poly-L-lactic acid degradation in vitro and in vivo

Abstract

As a promising candidate, biodegradable Poly-L-lactic Acid (PLLA) has been extensively used in coronary artery stents. In our previous reports, PLLA stents implanted in porcine coronary arteries showed safety without stent thrombosis. However, inflammatory responses were observed, which needed further study. In this study, human aortic endothelial cells (HAEC) were treated with different volume percentages of extract of pre-degraded PLLA (extract of PLLA) in vitro, and the cell growth curve and morphological changes were examined. The expression of inflammatory cytokines such as NF-κB, VEGF and VCAM-1 were also observed by ELISA. In addition, PLLA stent was implanted in porcine coronary artery to examine morphological changes, functional marker eNOS and inflammatory responses. The extract of PLLA caused significant growth inhibition and release of NF-κB, VEGF and VCAM-1 in HAEC with volume percentage-dependence. Although re-endothelialization and expression of eNOS was observed, expression of NF-κB and lymphocytes surrounding PLLA were also found after PLLA stents were implanted in the artery. This study demonstrated the effects of inflammation on endothelial cells induced by PLLA degradation in vitro and showed the inflammation in vivo, suggesting that anti-inflammatory strategy is necessary for PLLA stent implantation in the artery.     

Cajal间质细胞的研究进展

Cajal间质细胞(interstitial cells of Cajal,ICC)是一类主要分布于胃肠道的间质细胞,是胃肠道的起搏细胞(pacemaker cell)和信号传导细胞,与肌细胞以及末梢神经元有着紧密的关系,具有激发和促进胃肠蠕动的作用.借助于电子显微镜技术,清楚观察到了ICC位置分布和内部精细结构;应用免疫荧光等生化技术,发现了其特殊表达的C-kit蛋白;利用电生理技术,得知多种胃肠动力障碍疾病也与其异常有关.多年来,学者逐渐在胃肠道、胆道、膀胱、子宫等部位发现了ICC的踪迹,并试图阐述其与某些疾病的发生机制.本文就ICC的起源、形态学、受体和功能、以及与其相关的疾病等作一综述.     

Towards clinical data-driven eligibility criteria optimization for interventional COVID-19 clinical trials

ObjectiveThis research aims to evaluate the impact of eligibility criteria on recruitment and observable clinical outcomes of COVID-19 clinical trials using electronic health record (EHR) data.Materials and MethodsOn June 18, 2020, we identified frequently used eligibility criteria from all the interventional COVID-19 trials in ClinicalTrials.gov (n = 288), including age, pregnancy, oxygen saturation, alanine/aspartate aminotransferase, platelets, and estimated glomerular filtration rate. We applied the frequently used criteria to the EHR data of COVID-19 patients in Columbia University Irving Medical Center (CUIMC) (March 2020–June 2020) and evaluated their impact on patient accrual and the occurrence of a composite endpoint of mechanical ventilation, tracheostomy, and in-hospital death.ResultsThere were 3251 patients diagnosed with COVID-19 from the CUIMC EHR included in the analysis. The median follow-up period was 10 days (interquartile range 4–28 days). The composite events occurred in 18.1% (n = 587) of the COVID-19 cohort during the follow-up. In a hypothetical trial with common eligibility criteria, 33.6% (690/2051) were eligible among patients with evaluable data and 22.2% (153/690) had the composite event.DiscussionBy adjusting the thresholds of common eligibility criteria based on the characteristics of COVID-19 patients, we could observe more composite events from fewer patients.ConclusionsThis research demonstrated the potential of using the EHR data of COVID-19 patients to inform the selection of eligibility criteria and their thresholds, supporting data-driven optimization of participant selection towards improved statistical power of COVID-19 trials.     

An Embryonic Diapause-like Adaptation with Suppressed Myc Activity Enables Tumor Treatment Persistence

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