Chiral separation of β-blockers after derivatization with (−)-menthyl chloroformate by reversed-phase high performance liquid chromatography

Optimum conditions of chiral derivatization reaction of beta-blockers acebutolol, arotinolol, beta-xolol, bisoprolol, celiprolol, metoprolol and pindolol) with (-)-menthyl chloroformate were investigated for the resolution by HPLC. With more than 30 times molar excess of (-)-menthyl chloroformate chiral derivatization reactions were completed within one hour at room temperature except arotinolol and celiprolol. Diastereomeric derivatives of beta-blockers were well resolved on the ODS column using acetonitrile-methanol-water as a mobile phase.     

Synthesis of 4-hydroxy-1-thiocoumarin derivatives-1: An efficient synthesis of thioflocoumafen

An efficient procedure for the preparation of 4-hydroxy-3-{1,2,3,4-tetra-hydro-3-[4-(4-triflu-oromethylbenzyl oxy)phenyl]-1-naphthyl}thiocoumarin (thioflocoumafen, 1a and 1b) is described. The key step in the synthesis involves the condensation reaction of 3-(4-methoxyphenyl)-1-tetralol (2) with 4-hydroxy-1-thiocoumarin (3).     

Studies on constituents of Korean basidiomycetes (L)

To find antitumor metabolites in Korean basidiomycetes, the shake-cultured mycelia of eight of the higher fungi were extracted with hot water and the extracts, after being partially purified, were subjected toin vivo antitumor test. When administeredi.p. at the dose of 30mg/kg/day for ten consecutive days into the female ICR mice, which had been implanted with 1×10⁵ cells of sarcoma 180 twenty-four hours before the first injection, the extracts ofAgaricus campestris, Lyophyllum decastes, Lyophyllum ulmarium, Armillaria tabescence andCalvatia exipulitormis respectively showed inhibition ratios of 64.1%, 65.4%, 60.0%, 53.0% and 49.3%. These five species were selected for further study, whereas the extracts ofPhallus impudicus, Coprinus comatus andPholiota squarrosa which showed the inhibition ratios of 31.2%, 33.5% and 19.0% were discontinued.     

Selective neuronal survival and upregulation of PCNA in the rat inner retina following transient ischemia

In this study we investigated the extent and time course of neuronal cell death and the regulation of the proliferating cell nuclear antigen (PCNA) in the different retinal cell layers following ischemia-reperfusion injury. Retinal ischemia was induced by controlled elevation of the intraocular pressure for a duration of 60 min. Changes in thickness and cell numbers in the retinal cell layers were analyzed at various time points (1 h to 4 weeks) after reperfusion. In parallel, apoptotic cell death was determined by the TUNEL method and the expression of PCNA analyzed by immunocytochemistry. In addition, we tested whether PCNA is expressed in neurons by double immunocytochemistry. The reduction in thickness was found to be less pronounced in the inner nuclear layer (INL). Correspondingly, cell numbers decreased by only 33% in the inner retina, but by more than 80% in the outer nuclear layer (ONL). Alterations in glial cell numbers did not contribute significantly to postischemic changes in the INL and ONL as assessed by using immunocytochemical markers for microglial and Müller cells. The time course of cell death determined by the TUNEL technique also differed markedly in the retinal layers being rapid and transient in the inner retina but delayed and prolonged in the ONL. PCNA immunoreactivity was undetectable in the normal retina, but was specifically induced in neurons of the inner retina within 1 h after reperfusion and was sustained for at least 4 weeks. We conclude that in contrast to photoreceptors in the ONL, a significant proportion of inner retinal neurons is resistant to ischemic insult induced by transiently increased intraocular pressure and that PCNA may possibly play a role in the selective postischemic survival of these cells.     

甘草饮片超微粉碎前后甘草酸溶出行为的比较研究

目的 :考察超微粉碎前后甘草饮片中甘草酸溶出行为变化规律。方法 :以甘草酸含量为测定指标 ,分别对不同的样品进行测定实验。结果 :超微粉碎后甘草酸的溶出显著提高 ,且粉碎时间越长 ,粒度越细 ,甘草酸溶出越易。结论 :超微粉碎后有助于甘草饮片中甘草酸的溶出 ,粉碎粒度对甘草酸的溶出有显著的影响。     

穿破石挥发性成分的研究

目的 :研究穿破石中的挥发性成分。方法 :利用水蒸气蒸馏法提取穿破石挥发油 ,用GC-MS进行测定 ,结合计算机检索技术对分离的化合物进行结构鉴定 ,应用色谱峰面积归一化法计算各成分的相对百分含量。结果 :鉴定出 64个化学成分 ,其中相对百分率含量大于 1%的有23个成分 ,含量较高的是L 芳樟醇 (L-linalool)9.852%。结论 :64个挥发性成分均为首次从该植物中得到。     

桂枝汤及其活性成分对EP3受体激动剂诱导发热的影响

的 :研究桂枝汤及其有效成分对EP₃ 受体激动剂诱导大鼠发热的影响。方法 :对比观察侧脑室注射sulprostone(Sul)发热模型组与桂枝汤、肉桂醛、肉桂酸和白芍总苷治疗组大鼠体温变化。结果 :桂枝汤和肉桂醛灌胃均能抑制Sul脑室注射诱导的体温升高 ,白芍总苷腹腔注射可使发热大鼠体温降至正常以下 ,而肉桂酸倾向于增强该发热反应。结论 :抑制EP₃ 受体后与发热相关的信号转导通路可能是桂枝汤、肉桂醛和白芍总苷的解热作用机理之一 ,而肉桂酸可能对该通路无明显影响。     

千斤拔挥发性成分的研究

目的：研究千斤拔中的挥发性成分。方法：利用水蒸气蒸馏法提取千斤拔(Radix Flemingiae philippinensis）挥发油，用GC—MS进行测定，结合计算机检索技术对分离的化合物进行结构鉴定，应用色谱峰面积归一化法计算各成分的相对百分含量。结果：鉴定出39个化学成分，其中相对百分率含量大于4％的分别确定为α—雪松烯(1)，γ—雪松烯(2)，β—雪松烯(3)，β—愈创烯(4)，Italiccnc(5)。结论：千斤拔挥发油中近80％成分已查清。     

nCPAP治疗对阻塞性睡眠呼吸暂停综合征患者动态血压的影响

目的:探讨经鼻持续气道正压通气(nCPAP)治疗,对阻塞性睡眠呼吸暂停综合征(OSAS)合并高血压患者动态血压的影响。方法:22例男性患者行多导睡眠图(PSG)监测及动态血压检查确诊为OSAS合并高血压的患者,观察nCPAP治疗前后患者动态血压、多导睡眠图等多项指标变化。结果:nCPAP治疗后患者PSG参数明显改善:睡眠时最低SaO_2从(71.0±12.3)％上升到(91.7±7.3)％(P<0.01);RDI显著降低;同时24小时血压明显下降,治疗前血压(16.5±1.6/11.6±2.3Kpa),治疗后血压(13.7±1.5/9.3±1.4Kpa)(P<0.01)。结论:经鼻持续气道正压通气治疗阻塞性睡眠呼吸暂停综合征,不但可以纠正患者的呼吸暂停,改善临床症状,而且可能降低患者的血压。     

南昌链霉菌生物合成梅岭霉素种子制备优化

以参数相关理论为指导,优化南昌链霉菌生物合成梅岭霉素种子制备工艺。结果表明,培养20～35h后,pH7.30～7.50,总糖<0.35%,pmv>10%,溶磷<100μg/ml,菌丝分化启动有利于提高梅岭霉素的发酵效价。