Comparison of the haemodynamic effects of intermittent positive pressure ventilation with high frequency jet ventilation

The cardiorespiratory effects of intermittent positive pressure ventilation and high frequency jet ventilation with and without positive end expiratory pressure were compared in patients following valvular heart surgery (mitral and/or aortic). Twenty patients received intermittent positive pressure ventilation and high frequency jet ventilation with 0, 0.5 and 1.0 kPa positive end expiratory pressure. High frequency jet ventilation was well tolerated. The addition of 1.0 kPa positive end expiratory pressure was associated with preservation of the arterial oxygen tension without any increase in shunt or significant adverse haemodynamic effect. The results are discussed and compared with a previous study of high frequency jet ventilation following aortocoronary bypass graft surgery.     

High-quality recording of bioelectric events

A multichannel instrumentation amplifier, developed to be used in a miniature universal eight-channel amplifier module, is described. After discussing the specific properties of a bioelectric recording, the difficulties of meeting the demanded specifications with a design based on operational amplifiers are reviewed. Because it proved impossible to achieve the demanded combination of low noise and low power consumption using commercially available operational amplifiers, an amplifier equipped with an input stage with discrete transistors was developed. A new design concept was used to expand the design to a multichannel version with an equivalent input noise voltage of 0·35 μV RMS in a bandwidth of 0·1–100 Hz and a power consumption of 0·6 mW per channel. The results of this study are applied to miniature, universal, eight-channel amplifier modules, manufactured with thick-film production techniques. The modules can be coupled to satisfy the demand for a multiple of eight channels. The low power consumption enables the modules to be used in all kinds of portable and telemetry measurement systems and simplifies the power supply in stationary measurement systems.     

Bent knees and tiptoeing: late manifestations of end-stage Parkinson's disease.

We describe a unique gait phenomenon of bent knees in 9 patients with idiopathic Parkinson disease (mean age, 73.1 +/- 11.1 years), 3 of whom also manifested tiptoeing. The bent-knee posture appeared only during ambulation; in the recumbent position, full or nearly full extension was possible in all patients. The abnormality emerged after long-standing disease (6-23 years from onset) and failed to respond to dopaminergic treatment. Most of the patients also had bent spine (camptocormia). The pathogenesis of these phenomena are unknown, but they might represent a rare type of dystonia.     

糖基化终末产物对大鼠肾系膜细胞纤溶酶原激活物抑制物-1表达韵影响

目的：观察糖基化终末产物（AGEs）对大鼠肾系膜细胞纤溶酶原激活物抑制物-1（PAI-1）表达的影响及其与细胞外基质（ECM）成分含量的关系。方法：体外培养正常大鼠肾系膜细胞，分别用糖化牛血清白蛋白（AGEs）及未经糖化的牛血清白蛋白（BSA）处理，以常规培养的肾系膜细胞作为对照，检测不同时间、不同浓度AGEs对纤维连接蛋白（FN）、Ⅳ型胶原、PAI-1表达的影响。MTT法检测AGEs对系膜细胞增殖的作用，ELISA测定条件培养基中FN、Ⅳ型胶原及PAI-1蛋白含量，逆转录聚合酶链式反应（RT—PCR）检测系膜细胞PAI-1 mRNA的表达。结果：与相应浓度的BSA比较，AGEs（0—200mg／L）对系膜细胞增殖无明显影响，但可不同程度地刺激系膜细胞FN、Ⅳ型胶原、PAI-1蛋白的产生。RT—PCR检测显示，给予AGEs（100mg／L）的系膜细胞PAI-1 mRNA的表达明显增加（P〈0．01）。结论：AGEs促进系膜细胞PAI—1的表达，提示AGEs通过上调PAI-1的表达而减少细胞外基质降解，可能是糖尿病肾病细胞外基质积聚的原因之一。     

Low molecular weight advanced glycation end products predict mortality in asymptomatic patients receiving chronic haemodialysis.

BACKGROUND: Advanced glycation end products (AGEs) have biological properties that may contribute to the premature cardiovascular mortality of haemodialysis patients. This study examines the hypothesis that low molecular weight forms of fluorescent AGEs (LMW fluorescence) predict mortality in haemodialysis patients. METHODS: The LMW fluorescence was measured in 85 patients treated with chronic haemodialysis and prospectively followed for 4 years. The primary outcome of all-cause mortality was assessed using Cox proportional hazards regression model. RESULTS: At the end of the follow-up period 37 (44%) patients died. The median LMW fluorescence level was 24.2 arbitrary units (range: 10.6-148.1 AU) and the receiver operator characteristic (ROC) curve cut-off for mortality was 37.0 AU. The LMW fluorescence predicted death both as a binary variable at the ROC cut-off, and as a continuous log-transformed variable when adjusted for age, albumin and C-reactive protein (CRP). Adjusted for age, albumin and CRP, the hazard ratio for mortality was 3.05 (1.41-6.60, P = 0.005) for LMW fluorescence as a binary variable and 2.71 per log unit (1.37-5.38, P = 0.004) as a continuous log-transformed variable. CONCLUSION: The low molecular weight forms of AGEs predict mortality in patients receiving chronic haemodialysis, and may be important in the mechanisms leading to atherosclerosis and inflammation in such patients.     

血浆中高级糖化终产物的水平与糖尿病并发症的关系研究

目的 探讨高级糖化终产物与糖尿病并发症的关系。方法 采用本实验室自行研制的竞争性酶联免疫吸附分析方法，测定了糖尿病有并发症组病人血浆95例，糖尿病无并发症组人血浆65例，正常对照65例。结果：在糖尿病有并发症组中，高级糖化终产物（AGEs）浓度[（6．625（1．691）U／mL，n=95]明显高于糖尿病无并发症组[（5．904（2．071）U／mL，n=65，P=0．017]，也明显高于正常人组[（5．337（1．138，n=65，p〈0．005]。以有无并发症为应变量进行多元logistic回归分析显示，血浆AGEs浓度〉6．085U／ml者，糖尿病并发症发生的危险性增加（OR值为2．989，95％可信限为1．407—6．350）。多元逐步线性回归显示：糖尿病病程、冠心病史与血浆AGEs浓度之间有线性关系。结论血浆AGEs浓度是糖尿病发生并发症的独立危险因素。     

安桃乐气体吸入在分娩镇痛中对母婴影响的观察分析

目的:探讨安桃乐(ENTONOX)气体吸入对分娩镇痛及母婴结局的影响。方法:将181名无产科或内科合并症的住院产妇随机分成两组,一组由家属全程陪护,另一组由家属全程陪护+安桃乐气体吸入,观察两组产妇的镇痛效果、产程进展、分娩方式、新生儿Apgar评分情况、产后出血量。结果:ENTONOX吸入对分娩镇痛有效率达98.2％,显效率达80.7％,对产程进展有促进作用,对分娩方式、围产儿结局、产后出血量无显著性差异。结论:ENTONOX吸入镇痛是一种安全、有效的辅助分娩技术,作用迅速、费用低廉,是产妇乐意接受的镇痛方法。     

Select types of supporting cell in the inner ear express aquaporin-4 water channel protein

Aquaporins (AQPs) confer a high water permeability on cell membranes and play important parts in secretory and absorptive epithelia in kidney and other organs. Here we investigate whether AQPs are expressed in the sensory epithelia of the inner ear, where a precise volume regulation is crucial. By use of specific antibodies it was found that the inner ear contains AQP1 and 4 while being devoid of detectable levels of AQP2, 3 or 5. Immunofluorescence and postembedding immunogold labelling revealed a strictly non-epithelial distribution of AQP1, confirming previous data. In contrast, AQP4 protein and mRNA (visualized by in situ hybridization) were concentrated in select types of supporting cell, including Hensen's cells and inner sulcus cells. Immunogold particles signalling AQP4 were confined to the basolateral plasma membrane of Hensen's cells and to the basal plasma membrane of Claudius cells and inner sulcus cells. AQP4 was also found in supporting cells of the vestibular end organs, but was absent from transitional epithelial cells and dark cells. Strong labelling for AQP4 and AQP4-mRNA was associated with the central part of the cochlear and vestibular nerves. Hair cells were consistently unlabelled. Our findings indicate that AQP4 may facilitate osmotically driven water fluxes in the sensory epithelia of the inner ear and thus contribute to the volume and ion homeostasis at these sites.     

Is monoamine oxidase inhibitor induced myoclonus serotoninergically mediated?

Summary In the present study a single case observation of myoclonus during sleep-wave transition was monitored in a depressed patient treated with the monoamine oxidase inhibitor, phenelzine. The myoclonus had a rhythm of 1 c/second and lasted for two years, the duration of phenelzine treatment. Myoclonus appeared neither during wakefulness nor during sleep, but at wake-sleep-wake transitions. This switch myoclonus was associated with phasic muscle hyperactivity during REM sleep.Methysergide a 5-HT suppressor, decreased the switch myoclonus frequency and the REM muscle hyperactivity, indicating serotoninergic involvement in the mechanism of phenelzine induced myoclonus.