Aloe‐emodin: A review of its pharmacology,toxicity, and pharmacokinetics

Aloe‐emodin is a naturally anthraquinone derivative and an active ingredient of Chinese herbs, such as Cassia occidentalis, Rheum palmatum L., Aloe vera, and Polygonum multiflorum Thunb. Emerging evidence suggests that aloe‐emodin exhibits many pharmacological effects, including anticancer, antivirus, anti‐inflammatory, antibacterial, antiparasitic, neuroprotective, and hepatoprotective activities. These pharmacological properties lay the foundation for the treatment of various diseases, including influenza virus, inflammation, sepsis, Alzheimer's disease, glaucoma, malaria, liver fibrosis, psoriasis, Type 2 diabetes, growth disorders, and several types of cancers. However, an increasing number of published studies have reported adverse effects of aloe‐emodin. The primary toxicity among these reports is hepatotoxicity and nephrotoxicity, which are of wide concern worldwide. Pharmacokinetic studies have demonstrated that aloe‐emodin has a poor intestinal absorption, short elimination half‐life, and low bioavailability. This review aims to provide a comprehensive summary of the pharmacology, toxicity, and pharmacokinetics of aloe‐emodin reported to date with an emphasis on its biological properties and mechanisms of action.     

PI3K抑制剂ZSTK-474对结直肠癌细胞增殖和侵袭的影响

目的:探讨PI3K抑制剂ZSTK-474对结直肠癌细胞增殖和侵袭的影响。方法:采用不同浓度（0、1、2、4、6、8和10 μmol/L）ZSTK-474处理结直肠癌HT-29和HCT-116细胞24 h和48 h，CCK8法检测细胞增殖活性并计算出ZSTK-474在两株结直肠癌细胞中的半数抑制浓度（IC50）。根据IC50的值选用浓度为4 μmol/L的ZSTK-474作用HT-29和HCT-116细胞24 h，同时设置加入等量的0.1%DMSO为对照。采用平板克隆形成实验检测细胞增殖，流式细胞仪检测细胞凋亡，qRT-PCR检测细胞PI3K、Akt的mRNA水平，Western blot 检测细胞PI3K、Akt的蛋白水平。结果:ZSTK-474可明显抑制HT-29和HCT-116细胞的增殖，且呈时间和剂量依赖性。ZSTK-474可抑制HT-29和HCT-116细胞的侵袭能力，但不影响其凋亡。ZSTK-474处理HT-29和HCT-116细胞24 h后，PI3K和Akt的mRNA和蛋白表达水平均显著下降。结论:ZSTK-474能够抑制结直肠癌细胞增殖，并且能抑制其侵袭。     

临床医学专业“5+3”一体化本科全程导师制创新人才培养的实践与探索

以培养创新型人才为目标，大连医科大学制定实施了“5+3”创新人才培养改革方案，以导师制培养为载体，在医学本科教育全过程中，制定分阶段创新能力培养体系，涵盖课程、讲座、实验设计、论文等基本科研能力训练，强化本科生科研能力培养。通过对首届“5+3”学生阶段性培养成果的统计学分析发现，“5+3”学生发表中文期刊、SCI，主持国家级创新项目、省级创新项目的比例均显著高于普通5年制学生，差异具有统计学意义（P<0.05）。虽然实施过程中存在一些问题和不足，但以导师制为核心的科研基础训练对提高学生科研思维和创新能力效果显著，对培养医学创新型人才具有可实施性。     

儿童支气管哮喘与注意缺陷多动障碍的关系及其危险因素

近年来儿童慢性疾病与神经精神疾病的关系及其致病机制已成为儿科领域研究的热点和难点。支气管哮喘(简称哮喘)是儿童期常见的慢性疾病之一,最新基于人群的大样本报道证实哮喘与儿童最常见的神经发育障碍性疾病注意缺陷多动障碍(ADHD)之间关系密切。现就哮喘和ADHD的具体关系及其危险因素最新研究进展进行综述,以期认识二者之间的关系及其危险因素,便于哮喘患儿的长程临床管理。     

Quantitative chemical exchange saturation transfer (qCEST) MRI – omega plot analysis of RF‐spillover‐corrected inverse CEST ratio asymmetry for simultaneous determination of labile proton ratio and exchange rate

Chemical exchange saturation transfer (CEST) MRI is sensitive to labile proton concentration and exchange rate, thus allowing measurement of dilute CEST agent and microenvironmental properties. However, CEST measurement depends not only on the CEST agent properties but also on the experimental conditions. Quantitative CEST (qCEST) analysis has been proposed to address the limitation of the commonly used simplistic CEST‐weighted calculation. Recent research has shown that the concomitant direct RF saturation (spillover) effect can be corrected using an inverse CEST ratio calculation. We postulated that a simplified qCEST analysis is feasible with omega plot analysis of the inverse CEST asymmetry calculation. Specifically, simulations showed that the numerically derived labile proton ratio and exchange rate were in good agreement with input values. In addition, the qCEST analysis was confirmed experimentally in a phantom with concurrent variation in CEST agent concentration and pH. Also, we demonstrated that the derived labile proton ratio increased linearly with creatine concentration (P < 0.01) while the pH‐dependent exchange rate followed a dominantly base‐catalyzed exchange relationship (P < 0.01). In summary, our study verified that a simplified qCEST analysis can simultaneously determine labile proton ratio and exchange rate in a relatively complex in vitro CEST system. Copyright © 2015 John Wiley & Sons, Ltd.