Assessment of microtubule stabilizers by semiautomated in vitro microtubule protein polymerization and mitotic block assays

Paclitaxel (Taxol) a clinically active anticancer agent, exerts its cytotoxicity by inducing tubulin polymerization, leading to cellular mitotic block. In contrast, other antimitotic drugs, such as colchicine, podophyllotoxin, and vinblastine, act by depolymerizing microtubules. We report here (a) a semiautomated assay which measures the tubulin-polymerizing activity of paclitaxel analogs and (b) a cellular assay to measure the potential of these compounds to block cells in mitosis. The microtubule-polymerizing assay measured the turbidity of bovine brain microtubule protein (MTP) polymerized by the test compound in a 96-well plate. We maximized the sensitivity of this assay by conducting the polymerization reaction at 20 °C, at which temperature the baseline reaction, i.e. the basic ability of the untreated MTP control to polymerize, was minimal. At 20 °C, the effect of 0.05 μg/ml of paclitaxel on MTP could be detected, whereas at 37 °C, >1 μg/ml of paclitaxel was required to detect a significant effect relative to untreated MTP. We describe the analysis of the complex curves of MTP polymerization with varying concentrations of test compounds. The polymerization of microtubules leads to cells being blocked in mitosis. This mitotic blocking effect in intact cells was determined using a cell settling chamber which allowed eight samples to be deposited on a slide. This method required a smaller number of cells (10³–10⁵), maintained cell morphology, and allowed for rapid screening of samples. The activity of several new paclitaxel analogs is reported. Received: 9 May 1996 / Accepted: 5 March 1997     

三种方法治疗肩周炎90例疗效比较

目的 比较肩周炎患者采用三种不同治疗方法的疗效。方法 选择90例肩周炎患者，随机分为三组，每组30例，各组条件基本一致，采用三种不同方法，进行疗效比较。A组口服消炎镇痛药芬必得每次0．6g，每日2次，通经活血药盘龙七每次0．6g，每日3次，10d为1个疗程；汽化药热疗，每日1次，10d为1个疗程。功能锻炼，每日数次。B组肩胛上神经阻滞（1％利多卡因10ml＋醋酸强的松龙25mg＋维生素B1 100mg＋维生素B12 500μg），口服盘龙七＋汽化药热疗＋功能锻炼。C组肌间沟臂丛神经阻滞（1％利多卡因10m1），待阻滞完善后行手法松解肩关节的粘连，松解粘连后采用痛点阻滞（2％利多卡因2ml＋醋酸强的松龙25mg＋维生素B1 100mg＋维生素B12 500μg），口服盘龙七＋功能锻炼。结果 三组治愈率：A组13％，B组66％，C组93％。C组明显优于A、B组（P〈0．05）。结论 综合疗法是治疗肩周炎较理想的治疗方法。     

Interaction of topiramate with glycine receptor channels

Glycine receptor channels are pentameric ligand-gated ion channels that respond to the application of inhibitory neurotransmitters by opening of a chloride-selective central pore. Topiramate (TPM) is a broad-spectrum antiepileptic drug used as add-on or monotherapy for focal seizures. In the present study the interaction of TPM with glycine receptor channels was studied on outside-out patches from HEK293 cells expressing alpha1beta glycine receptor channels. The patch clamp techniques combined with ultra fast solution exchange enabled us to investigate the kinetics of receptor channels in presence of TPM. Our study showed no agonistic or potentiating effect for TPM on glycine receptor channels. However, in presence of 1 mM glycine + 1 mM TPM, the desensitization got faster and the peak current amplitude decreased. After the end of glycine + TPM pulses, off-currents occurred, suggestive for a specific channel block mechanism.     

Effects of peribulbar bupivacaine as an adjunct to general anaesthesia on peri-operative outcome following retinal detachment surgery

Sixty premedicated, ASA physical status I or II patients weighing > 25 kg scheduled for elective retinal detachment repair were randomly assigned to receive either peribulbar block with 10 ml of 0.25% bupivacaine (block group) or intravenous morphine 150 microg.kg-1 (morphine group), prior to the induction of general anaesthesia (n = 30 in each group). Patients were evaluated for intra-operative oculocardiac reflex, peri-operative pain relief, recovery from anaesthesia and postoperative nausea and vomiting. Apart from significantly reducing the incidence of oculocardiac reflex (30% vs. 70%, p = 0.0019), peribulbar bupivacaine also attenuated the severity of the reflex. Postoperative pain relief was superior in the block group. More block group patients had the maximum recovery score in the immediate postoperative period (80% vs. 27%, p < 0. 0001) and they achieved complete recovery significantly faster than the morphine group (17.3 (14.7) min vs. 66.7 (29.7) min, p < 0.0001). The incidence (40% vs. 77%, p = 0.004) and severity of postoperative nausea and vomiting were significantly less in the block group. In summary, peribulbar bupivacaine, when administered together with general anaesthesia, attenuated oculocardiac reflex, provided comparable intra-operative and superior postoperative analgesia, resulted in significantly earlier and better recovery from anaesthesia, and significantly reduced the incidence and severity of postoperative nausea and vomiting.     

静脉全麻复合骶管阻滞在婴幼儿先天性心脏病介人封堵治疗的研究

目的比较静脉全麻复合单次骶管阻滞麻醉与单纯静脉全麻用于婴幼儿先天性心脏病介入封堵治疗的效果。方法616例婴幼儿先天性心脏病介入封堵治疗患者随机分成两组:骶管阻滞加静脉全麻(I组);另一组用全凭静脉麻醉(II组)。结果全麻药的用量,II组比I组明显增多(P<0.05);I组苏醒时间短,分泌物少,手术后呕吐发生率少(P<0.05)。结论静脉全麻复合小儿单次骶管阻滞麻醉比全凭静脉麻醉用于婴幼儿先天性心脏病介入封堵治疗麻醉费用少,生命体征平稳,麻醉并发症少,值得推广。     

线型和星型聚乙二醇-聚己酸内酯两亲嵌段共聚物聚集行为

分别以单甲氧基聚乙二醇和4臂聚乙二醇引发己酸内酯开环聚合制得线型和星型聚乙二醇-聚己酸内酯(PEG-PCL)两亲嵌段共聚物。IR1、H-NMR和GPC测试结果表明所合成的共聚物具有预期的结构。该PEG-PCL两亲嵌段共聚物中PEG组分具有结晶性。共聚物在水相中自组装形成聚集体,聚集体的水合直径小于50 nm。高浓度共聚物在水性介质中会发生凝胶-溶胶转变,在凝胶-溶胶转变温度以下,共聚物形成凝胶网状结构。共聚物中PEG组分的结晶性、在水相中生成的聚集体的水合直径以及凝胶-溶胶转变行为均与聚合物的组成以及分子形状密切相关。     

房室结阻断加永久起搏与房室结改良治疗心房纤颤的疗效研究

目的评价房室结阻断加永久起搏(AVNAP)和房室结改良(AVNM)治疗心房纤颤(AF)的效果.方法32例药物难治性AF患者,分成AVNAP(18例)和AVNM(14例)两组.采用NYHA心功能分级、左室射血分数(LVEF)、6 m in步行试验(6-MWT)、“SF-36问卷”生活质量评分等方法进行评价.结果平均随诊14月,AVNAP组LVEF由治疗前的(47±9)%增至(57±6)%(P<0.01),心功能分级由2.2±0.7降至1.4±0.5(P<0.05),6-MWT明显增加,SF-36生活质量评分明显改善.住院次数明显减少、停服抗心律失常药.AVNM组LVEF、心功能、6-MWT、生活质量的改善不如AVNAP组.结论对药物难治性AF、AVNAP和AVNM均有效,但AVNAP明显优于AVNM和常规药物治疗.     

硬膜外阻滞加静吸复合麻醉对腹腔镜结肠癌根治术应激反应的影响

目的评价硬膜外阻滞加静吸复合麻醉对腹腔镜结肠癌根治术应激反应的影响。方法28例择期行腹腔镜结肠癌根治术的患者,随机分为硬膜外阻滞加静吸复合麻醉组(GE组)和单纯静吸复合全麻组(G组),每组各14例。分别监测人工气腹前和气腹后1、2、3h的MAP、ECG、HR、SpO2及PETCO2的情况,并同时进行血气分析和血肾上腺素(E)及去甲肾上腺素(NE)浓度的测定。结果于气腹后1、2、3h时,E和NE值两组均较气腹前升高,但G组升高尤为显著(P<0.05),而组间比较,GE组明显低于G组(P<0.05);G组MAP、HR均较气腹前升高(P<0.05),GE组HR较气腹前降低(P<0.05),而组间比较,MAP、HR差异有统计学意义(P<0.05);PaCO2值与气腹前比较两组差异均有统计学意义(P<0.05);而气腹后3hpH值低于正常值,与气腹前比较差异有统计学意义(P<0.05)。结论硬膜外阻滞加静吸复合麻醉可有效地抑制腹腔镜结肠癌根治术中因较长时间气腹所引起的应激反应。