常见抗生素与新型抗菌药物在临床上的研究应用进展

摘要：抗生素的研发与使用有效杀灭和抑制了众多病原菌，挽救了无数人的生命，但由于抗生素的不合理使用，导致细菌耐 药不断出现，耐药菌的感染已严重地威胁人类的生命健康。为此，本文主要对近年来临床上常用的抗生素如β-内酰胺类、喹诺酮 类、氨基糖苷类药物以及新型抗菌药物如抗菌肽和纳米颗粒的应用研究进行总结分析与探讨，为临床上治疗疾病提供一些参考。     

基于SSR标记与化学成分构建十堰地区天师栗核心种质库＊

目的 利用筛选出十堰的天师栗中高多态性SSR位点评价天师栗种质资源的遗传多样性，结合有效药用成分含量，构建十堰地区天师栗核心种质库。方法 收集十堰地区114份天师栗种质资源，以七叶树基因组为参考，采用荧光毛细管电泳筛选出高多态性SSR位点，对天师栗种质资源进行遗传多样性分析。利用HPLC测定不同种质干燥娑罗子中七叶皂苷的含量。采用最小距离逐步聚类取样策略（LDSS），根据遗传多样性保留程度初步筛选出核心种质，并对该核心种质与原始种质的遗传多样性参数进行T检验，选择与原种质差异不显著的核心种质为最佳核心种质。结果 筛选出13对高多态性SSR分子标记，遗传多样性评价结果表明十堰地区天师栗种质资源遗传多样性较高，遗传分化较小，存在着较大的基因流，114份种质资源未分为不同的亚群，周家坝和辽叶居群间具有较近的遗传亲缘关系，且周家坝居群娑罗子中的七叶皂苷A及七叶皂苷B含量普遍较高。最终筛选出的核心种质共23份，占总种质资源的20.17%，其中周家坝12份样本、辽叶6份样本、普龄5份样本。结论 将SSR分子标记与主要有效药用成分结合，采用LDSS取样策略构建十堰地区天师栗种质资源核心种质库的方法具有可行性，能够有效的保存与管理天师栗种质资源，也为当地天师栗品种改良、新品种选育研究等提供了研究基础。     

Lysophosphatidylcholine‐induced cytotoxicity and protection by heparin in mouse brain bEND.3 endothelial cells

A pathological feature in atherosclerosis is the dysfunction and death of vascular endothelial cells (EC). Oxidized low‐density lipoprotein (LDL), known to accumulate in the atherosclerotic arterial walls, impairs endothelium‐dependent relaxation and causes EC apoptosis. A major bioactive ingredient of the oxidized LDL is lysophosphatidylcholine (LPC), which at higher concentrations causes apoptosis and necrosis in various EC. There is hitherto no report on LPC‐induced cytotoxicity in brain EC. In this work, we found that LPC caused cytosolic Ca²⁺ overload, mitochondrial membrane potential decrease, p38 activation, caspase 3 activation and eventually apoptotic death in mouse cerebral bEND.3 EC. In contrast to reported reactive oxygen species (ROS) generation by LPC in other EC, LPC did not trigger ROS formation in bEND.3 cells. Pharmacological inhibition of p38 alleviated LPC‐inflicted cell death. We examined whether heparin could be cytoprotective: although it could not suppress LPC‐triggered Ca²⁺ signal, p38 activation and mitochondrial membrane potential drop, it did suppress LPC‐induced caspase 3 activation and alleviate LPC‐inflicted cytotoxicity. Our data suggest LPC apoptotic death mechanisms in bEND.3 might involve mitochondrial membrane potential decrease and p38 activation. Heparin is protective against LPC cytotoxicity and might intervene steps between mitochondrial membrane potential drop/p38 activation and caspase 3 activation.     

Improvements in epidermal function prevent relapse of psoriasis: a self‐controlled study

While therapeutic approaches for psoriasis are widely available, preventive regimens are lacking. We aimed to determine whether improvements in epidermal function could prevent psoriasis relapse. Two self‐controlled cohort studies were designed, enrolling two cohorts of patients with psoriasis (n = 30 and n = 60) to be treated topically with an in‐house‐prepared emollient or ATOPALM^® cream applied twice daily to one forearm for 20 and 30 days, respectively, while the same sites on the contralateral arm served as the untreated control. Epidermal function on both arms was assessed prior to and at the end of the trials. Delayed relapse on the treated arm was seen in 54.5% and 71% of patients in the first and second cohort, respectively. The time of psoriatic relapse correlated with the extent of abnormalities in baseline epidermal function. These results suggest that improvements in epidermal function with topical emollients can prevent/attenuate the development of psoriasis.