Nitric oxide producing coating mimicking endothelium function for multifunctional vascular stents

The continuous release of nitric oxide (NO) by the native endothelium of blood vessels plays a substantial role in the cardiovascular physiology, as it influences important pathways of cardiovascular homeostasis, inhibits vascular smooth muscle cell (VSMC) proliferation, inhibits platelet activation and aggregation, and prevents atherosclerosis. In this study, a NO-catalytic bioactive coating that mimics this endothelium functionality was presented as a hemocompatible coating with potential to improve the biocompatibility of vascular stents. The NO-catalytic bioactive coating was obtained by covalent conjugation of 3,3-diselenodipropionic acid (SeDPA) with glutathione peroxidase (GPx)-like catalytic activity to generate NO from S-nitrosothiols (RSNOs) via specific catalytic reaction. The SeDPA was immobilized to an amine bearing plasma polymerized allylamine (PPAam) surface (SeDPA-PPAam). It showed long-term and continuous ability to catalytically decompose endogenous RSNO and generate NO. The generated NO remarkably increased the cGMP synthesis both in platelets and human umbilical artery smooth muscle cells (HUASMCs). The surface exhibited a remarkable suppression of collagen-induced platelet activation and aggregation. It suppressed the adhesion, proliferation and migration of HUASMCs. Additionally, it was found that the NO catalytic surface significantly enhanced human umbilical vein endothelial cell (HUVEC) adhesion, proliferation and migration. The in vivo results indicated that the NO catalytic surface created a favorable microenvironment of competitive growth of HUVECs over HUASMCs for promoting re-endothelialization and reducing restenosis of stents in vivo.     

Photodynamic immunopotentiation: in vitro activation of macrophages by treatment of mouse peritoneal cells with haematoporphyrin derivative and light

Peritoneal macrophages treated in vivo with haematoporphyrin derivative (HPD) exhibited significant enhancement of Fc receptor mediated ingestion activity. To examine this process more rigorously, we studied photodynamic activation of macrophages by exposure in vitro of mouse peritoneal cell cultures (containing macrophages and B and T-lymphocytes) to HPD and red fluorescent light. A short (10 s) exposure of peritoneal cells in medium containing 0.03 ng HPD/ml produced the maximal level of ingestion activity of macrophages. A singlet oxygen quencher, DABCO, inhibited the effect of HPD. Photodynamic treatment of macrophages alone did not activate the cells and activation was only observed when macrophages were mixed with photodynamically treated non-adherent cells (B and T-lymphocytes). These results imply that activation of macrophage is a consequence of peroxidation of lymphocyte membrane lipids by photodynamically generated singlet oxygen.     

N-正丁基-1-脱氧野尻霉素合成方法的改进

目的 改进N-正丁基-1-脱氧野尻霉素的合成方法。方法 本文通过酰化反应分别用丁酰氯和丁酸酐将丁酰基引入到2, 3, 4, 6-四苄基葡萄糖内酰胺的氮原子上,然后用氢化铝锂将两个羰基还原,得到N-正丁基-2, 3, 4, 6-四苄基-1-脱氧野尻霉素。结果与结论 本方法在改进部分可以将收率提高2~3倍,在氨解开环这一步,尝试用正丁基胺代替饱和氨气的甲醇溶液,并对其关环的产物以及副产物的生成机理进行了探讨。     

紫花前胡的化学成分研究

目的 对紫花前胡Peucedanum decursivum的化学成分进行研究.方法 采用95％乙醇提取,经多种色谱方法分离纯化,利用质谱、核磁共振等现代波谱技术鉴定结构.结果 从紫花前胡95％乙醇提取物的醋酸乙酯萃取物中分离得到12个化合物,分别鉴定为异佛手柑内酯(1)、佛手柑内酯(2)、茴芹内酯(3)、异茴芹内酯(4)、二氢欧山芹醇乙酯(5)、6-牛防风素(6)、前胡香豆素E(7)、花椒毒素(8)、甲氧基欧芹酚(9)、阿魏酸(10)、β-谷甾醇(11)、补骨脂素(12).结论 化合物1、4、5为首次从前胡属植物中分离得到,化合物2、3、6～10、12为首次从该植物中分离得到.     

款冬花的化学成分研究

目的：研究款冬花的化学成分。方法利用硅胶柱、高效液相等色谱技术对款冬花甲醇提取物进行分离纯化,通过波谱数据鉴定结构。结果从款冬花中共分得5个化合物,分别鉴定为：款冬酮（1）、14- acetoxy -7β-（4- methylsenecioyloxyl）-1α-（2＇- methylbutyryloxy）- notonipetranone（2）、6- acetyl -2,2- dimethylchroman -4- one（3）、3,4- epoxy -1,8- diangeloyloxy bisabola -7（14）-10- dien -2- one（4）以及橐吾香附酮醇（5）。结论化合物3～5为首次从该植物中分离得到。     

甘草酸协同麻黄碱的平喘作用机制研究

目的：探讨甘草酸协同麻黄碱的平喘作用机制。方法：利用基于CHO细胞的β₂肾上腺素受体（β₂-AR）激动药活性评价体系,豚鼠离体气管收缩和组胺引喘的活体动物模型观察甘草酸和麻黄碱联用的协同平喘效果。结果：甘草酸自身不能引起离体气管平滑肌舒张,平喘效果也不显著,但与麻黄碱联用可以通过提高β₂-AR的激动效果,明显增强平喘效果。结论：甘草酸通过调节β₂-AR信号通路增强麻黄碱的作用效果,两者联用有良好的协同作用。