Barrier function of porcine choroid plexus epithelial cells is modulated by cAMP-dependent pathways in vitro

In the present paper, we demonstrate that the barrier properties of primary cultured epithelial cells isolated from porcine choroid plexus are regulated by cAMP-dependent signal transduction pathways in vitro. Triggering cAMP-connected cascades in cell layers grown on permeable filters with cAMP-analogues or forskolin led to a significant increase of transepithelial electrical resistances and a pronounced reduction in the permeation rate of a 4 kDa-dextran probe. In dose-response experiments using the cAMP-analogue 8-(4-chlorophenylthio)-cAMP transepithelial electrical resistances were observed to increase above a threshold concentration ranging between 10(-5.5) and 10(-5) M. Additional impedance studies performed with confluent cell layers grown on gold-film electrodes revealed that the observed changes in transepithelial resistances and presumably also in macromolecular permeation rates were not entirely caused by a reinforcement of intercellular junctions but also contained contributions from changes in the cell-substrate adhesion pattern. These inherent contributions to the electrical resistance and macromolecular permeability are caused by a restricted diffusion pathway between basal plasma membrane and culture substrate that have to be considered in data analysis, especially when leaky cell layers on filter substrates with low pore densities are used.     

Treatment of refractory complex-partial status epilepticus with propofol: case report

PURPOSE: We report a case of a 65-year-old woman who had a subarachnoid and intraventricular hemorrhage secondary to rupture of an anterior communicating artery aneurysm and developed nonconvulsive status epilepticus of the complex-partial type, refractory to phenytoin (PHT), phenobarbital (PB), valproate (VPA), and lorazepam (LZP). METHODS: Three weeks after diagnosis of nonconvulsive status epilepticus, general anesthesia was induced with propofol and titrated to burst suppression on the electroencephalogram (EEG). RESULTS: During propofol infusion, the serum VPA level declined markedly, and despite >3 g daily doses, did not return to the therapeutic range, until several days after propofol was discontinued. Continuous propofol infusion was stopped after 7 days, and the patient recovered consciousness. Despite further complications, she gradually regained normal function and was discharged home 4 months after surgery. CONCLUSIONS: This is the first case of nonconvulsive status epilepticus successfully treated with propofol.     

Nitric oxide does not play a major role in the regulation of systemic hemodynamic responses to acute normovolemic hemodilution

Background: The mechanisms of cardiovascular changes following acute normovolemic hemodilution (ANH) have not been fully elucidated. We tested the hypothesis that inhibition of nitric oxide synthesis attenuates ANH-induced cardiovascular responses.
Methods: We observed the effects of N^ω-nitro-L-arginine methyl ester (L-NAME) pretreatment on ANH-induced cardiovascular responses and compared these effects with those elicited by phenylephrine (PHE). Twenty dogs anesthetized with isoflurane were divided into two groups: one group was pretreated with L-NAME and the other with PHE. Both groups were normovolemically hemodiluted using 6% hydroxyethyl starch to reduce the hemoglobin concentration to approximately 50% of the pretreatment value.
Results: Pretreatment with either L-NAME or PHE caused a significant increase in mean aortic blood pressure (MAP) and systemic vascular resistance (SVR) with a significant decrease in cardiac output (CO) and stroke volume (SV). However, no remarkable differences in these variables were seen between groups. In both groups ANH produced increases in heart rate, CO, SV, and maximal left ventricular dP/dt with a significant decrease in SVR. No significant differences in these variables were apparent after ANH except that MAP was decreased in the PHE group but not in the L-NAME group.
Conclusion: Our results suggest that nitric oxide does not play a major role in mediation or modulation of the systemic vascular responses to ANH.     

Total versus tube-related additional work of breathing in ventilator-dependent patients

BACKGROUND: In tracheally intubated or tracheostomized spontaneously breathing patients, tube resistance can highly increase the patient's work of breathing. In this study we focused upon the relationship between total (WOBtot) and tube-related additional inspiratory work of breathing (WOBadd) and compared different ventilatory modalities for proper tube compensation. METHODS: In ten tracheostomized spontaneously breathing patients we measured WOBtot and WOBadd in the continuous positive airway pressure (CPAP) mode, under inspiratory pressure support of 5, 10, and 15 cmH2O in the pressure support ventilation (PSV) mode, and under flow-adjusted pressure support in the automatic tube compensation (ATC) mode. WOBadd and WOBtot were calculated on the basis of measured tracheal pressure and esophageal pressure, respectively. Inspiratory peak tracheal pressure above PEEP was taken as an estimate of pressure support beyond mere tube compensation (i.e., overcompensation). RESULTS: The percentage of the tube-related WOBadd on WOBtot in the CPAP mode was 52%. It decreased with increasing pressure support in the PSV mode from 32% (PSV 5 cmH2O) to 17% (PSV 15 cmH2O). WOBadd was only 15% of WOBtot in the ATC mode. In contrast to the other ventilatory modes, reduction of WOBadd in the ATC mode was achieved with the smallest amount of overcompensation, i.e. with minimal pressure assist beyond mere tube compensation. CONCLUSION: In tracheally intubated or tracheostomized spontaneously breathing patients, adequate compensation of tube resistance (i.e. with minimal overcompensation and minimal undercompensation) is best done by the ATC mode.     

Patient-controlled intranasal diamorphine for postoperative pain: an acceptability study

A patient acceptability study was conducted using patient-controlled intranasal diamorphine. Patients undergoing nonemergency orthopaedic or gynaecological surgery self-administered intranasal diamorphine for 24 h postoperatively. Pain, pain relief, sedation, respiratory rate, nausea and vomiting were assessed regularly. After 24 h, patients and their attending nurses completed a questionnaire assessing satisfaction and practical aspects of the technique. Satisfaction was reported as good or complete by 69% of patients and 69% of nurses. Pain relief was assessed as better than expected by 45% of patients and better than normal by 50% of nurses. Seventy-nine per cent of patients would be pleased to use patient-controlled intranasal diamorphine again and 89% of nurses would be happy for their patients to use it again. Sedation was uncommon and mild and there were no episodes of significant respiratory depression. Fifty-three per cent of patients reported no nausea and 74% did not vomit at any stage. There were seven withdrawals, four due to problems with the device and three due to therapeutic problems. The nasal spray may need modification to improve reliability. However, we found patient-controlled intranasal analgesia an effective technique, which was well tolerated by patients and nurses and was without unpleasant side-effects. Further work to determine how it performs compared with intramuscular or intravenous analgesia is now needed.     

吸毒人员吸毒方式、性行为特点与HBV感染的关系研究

目的 了解湖南省吸毒人员乙型肝炎病毒(HBV)感染情况以及吸毒方式、性行为特点与HBV感染的关系。方法 采用现况研究，通过整群抽样，随机抽取某男性戒毒所和某女性戒毒所中的吸毒人员，以问卷的方式调查吸毒人员的吸毒方式和性行为特点，并用酶联免疫吸附试验(ELISA)检测血清中HBsAg、抗-HB、HHcAg、抗-HBc、抗-HBc，采用Chi-square检验对数据进行统计分析。结果 吸毒人员HBV感染率为63．2％；静脉注射和非静脉注射吸毒者HBV感染率分别为64．0％和59．4％，两者差异无显著性(P＞0．05)；有婚外性行为和无婚外性行为的吸毒人员HBV感染率分别为65．4％和55．2％，两者差异有显著性(P＜0．05)；不同性伙伴个数HBV感染率比较有显著性差异(P＜0．01)。结论 吸毒人群是HBV的高危人群，静脉吸毒与非静脉吸毒对HBV的感染无显著性差异，婚外性行为是HBV感染的主要危险因素，性伙伴个数是影响HBV感染的重要因素之一。     

膳食脂肪与肺癌的可能机制研究进展

大量的流行病学研究表明膳食脂肪与肺癌的关系非常密切 ,但尚缺乏有关机制方面的研究。本文综述了高脂膳食引发肺癌的可能机制 ,包括脂肪酸比例失调、胰岛素抵抗、脂质过氧化、内分泌机制、细胞因子分泌异常、细胞膜流动性改变等 ,旨在为以后的病因学研究提供参考。     

应用飞行时间质谱仪快速鉴定细菌的初步研究

目的　研究基质辅助激光解析电离飞行时间质谱对细菌快速鉴定的影响因素。方法　应用 8种细菌 ,比较了不同培养基 (哥伦比亚血琼脂、伊红美兰琼脂、普通营养琼脂 )及培养时间对细菌质谱图的影响。结果　不同的培养基及培养时间会对细菌质谱图产生影响。结论　选择合适的培养基及培养时间可以提高细菌检测的准确率     

2型糖尿病和葡萄糖耐量异常患者游离脂肪酸升高及其意义

目的　观察 2型糖尿病 (DM)和葡萄糖耐量异常 (IGT)患者血清游离脂肪酸 (FFA)的水平 ,探讨FFA与胰岛素(INS)、胰岛素抵抗 (IR)和甘油三酯 (TG)的关系。方法　采用酶法测定 2 0例 2型DM和 2 0例IGT患者口服葡萄糖耐量试验 (OGTT) 0和 2h血清FFA水平 ,同步测定血浆葡萄糖 (PG)、血清INS以及空腹TG和胆固醇 (TC) ,并与 2 0例正常人对照。结果　 2型DM和IGT患者OGTT 0和 2hINS均显著高于正常对照组 ,且 2型DM患者INS高于IGT患者 ,P <0 .0 5 ;空腹FFA和胰岛素抵抗指数 (HOMA -IR) 2型DM患者高于IGT患者 ,IGT患者高于正常对照组 ,P <0 .0 1;TG和OGTT 2hFFA 2型DM患者高于IGT患者和正常对照组 ,P <0 .0 5 ,而IGT患者和正常对照组之间比较差异无显著性 ;多元逐步回归显示空腹FFA是HOMA -IR的独立影响因素。结论　不仅 2型DM患者而且IGT患者存在FFA异常升高 ,FFA升高与IR有关 ;2型DM和IGT患者存在IR和脂代谢紊乱 ,FFA反映脂代谢紊乱可能较TG更灵敏的指标     

改良分子信标—实时PCR快速检测副溶血弧菌

目的 :建立改良分子信标 -实时 PCR检测副溶血弧菌的快速方法 ,应用于副溶血弧菌食物中毒的快速诊断和海产品检验。方法 :根据 Gen Bank公布副溶血弧菌的耐热直接溶血毒素基因 (TDH)的保守序列 ,设计一对引物和改良分子信标探针 ,用 FAM荧光剂标记探针的 5′,并进行特异性和灵敏度分析 ;同时以 11种细菌作对照 ,建立改良分子信标检测副溶血弧菌的实时 PCR反应体系 ,应用于副溶血弧菌食物中毒快速诊断和食品微生物检测。结果 :检测 12种细菌 ,只有副溶血弧菌有荧光信号 ,与其他细菌无交叉反应 ,DNA灵敏度为 16 6 .6 fg/ μl,菌液灵敏度为 6 9cfu/ ml或 6 cfu/ PCR反应体系。改良分子信标 -实时 PCR反应体系检测 4 0株副溶血弧菌均出现特异的荧光信号 ,无干扰。对 3起细菌性食物中毒共 4 8份样品和 10 0份海产品进行检测 ,9份副溶血弧菌实时 PCR阳性 ,其中 7份副溶血弧菌细菌培养阳性 ,其余样品都为阴性。检测时间仅需 2 h。结论 :改良分子信标 -实时 PCR检测体系快速、灵敏度高 ,特异性强 ,可用于副溶血弧菌食物中毒的快速诊断 ,为食源性疾病的分子流行病学调查提供新的检测手段