Diameters of the common carotid artery and aorta change in different directions during acute asphyxia in the fetal lamb

The aim of this experimental ultrasound study on six fetal lambs was to evaluate how blood flow variables and vessel diameters of the descending aorta and the common carotid artery change during fetal asphyxia in the acute preparation. When acute asphyxia was induced by obstructing the maternal aortic blood flow all fetuses reacted with significant decrease in the aortic diameter and blood flow. In the common carotid artery vessel diameter and the blood flow increased significantly. The results support the theory of a brain sparing effect during fetal distress with significant changes of blood vessel diameters occurring in opposite directions in the aorta and the common carotid artery, thereby contributing to the centralisation of circulation.     

铁道车祸危险因素与行车安全经济效益的探讨

作者以1380名机车乘务员为研究对象,测查其生理心理指标,探讨发生车祸的危险因素,分析34年车祸流行的规律,并对行车安全的社会经济效盖进行了估算。研究结果显示,社会安定是减少车祸、保证行车安全的重要因素。通过多因素分析,揭示车祸的危险因素是低文化程度、过度疲劳、睡眠不足、视运动反应迟钝和弱神经类型,其间存在交互作用。实践表明,推行安全行车千日活动,可获巨大社会经济效益(1∶7)。     

Evidence for differential effects of 8-OH-DPAT on male and female rats in the Anxiety/Defense Test Battery

The Proxemics/Activity test and the Eat/Drink test, two components of the Anxiety/Defense Test Battery, were developed to measure defensive reactions to situations associated with a natural predator (cat). In the present studies the behavioral effects of 8-OH-DPAT treatment (0.01–1.0 mg/kg, SC) were entirely consistent with anxiety/fear reduction. These effects included an increase in time spent near the cat compartment, and a complimentary decrease in time spent farthest from this compartment, together with an increase in transits and locomote behavior. 8-OH-DPAT (1.0 mg/kg) also increased eat frequencies and durations (highly preferred food) both during and following cat presentation, without influencing drinking. This finding is discussed with reference to previous findings with 8-OH-DPAT in studies assessing both food intake and anxiolysis. Interestingly, 8-OH-DPAT was more potent in a majority of its effects in female subjects, a finding consistent with recent neurochemical data. These findings provide important behavioral evidence for a sexual differentiation in 5-HT function, and support the case for greater emphasis on female subjects in animal models of anxiety.Supported by NIH MH42803 and RCMI Grants RR03061 and RR01825     

高血压病患者血清瘦素含量与胰岛素抵抗水平的相关性研究

目的：探讨高血压病患者血清瘦素水平与胰岛素抵抗的关系。方法：测定217例高血压病患者(男92例，女125例)的空腹血清瘦素含量、空腹血糖、胰岛素、收缩压、舒张压和体质量指数(BMI)，稳态模式评估法计算胰岛素抵抗指数(HOMA-IR)。分析瘦素与其他各项参数的相关性。结果：以HOMA—IR的25％位点，作为判断胰岛素抵抗的切割点，把高血压病患者分为胰岛素抵抗组(IR)和胰岛素敏感组(IS)，血清瘦素浓度IR组显著高于IS组(P＜0．05)。血清瘦素浓度与HOMA—IR呈显著正相关(男性r＝0．407，P＜0．01；女性r＝0．254，P＜0．01)；校正年龄和BMI后，男性组两者仍呈显著正相关(r＝0．219，P＜0．05)，女性组两者无相关；逐步回归分析显示，男性组HOMA—IR为血清瘦素浓度的独立预测因素。结论：男性高血压病患者血清瘦素浓度与胰岛素抵抗直接相关，女性则无直接相关性。性别差异的机制有待进一步探讨。     

Porins and lipopolysaccharide stimulate platelet activating factor synthesis by human mesangial cells.

Porins, a family of hydrophobic proteins located in the outer membrane of the cell wall of gram-negative bacteria and lipopolysaccharide (LPS), were shown to stimulate the synthesis of platelet activating factor (PAF), a phospholipid mediator of inflammation and endotoxic shock, by cultured human glomerular mesangial cells (MC). The synthesis of PAF induced by porins was rapid (peak at 20 min) and independent either from contamination by LPS or from generation of an endotoxin-induced cytokine such as tumor necrosis factor (TNF) since it was not prevented by cycloheximide, an inhibitor of protein synthesis or anti-TNF blocking antibodies. LPS also stimulated PAF synthesis by MC. However, the kinetic of PAF synthesis induced by LPS was biphasic with an early and transient peak at 10 minutes and a second and sustained peak at three to six hours. This second peak required an intact protein synthesis and was prevented by anti-TNF antibodies, suggesting the dependency on LPS-induced synthesis of TNF. Experiments with labeled precursors demonstrated that in MC, either after stimulation with porins or LPS, PAF was synthesized via the remodeling pathway that involves acetylation of 1-0-alkyl-sn-glyceryl-3-phosphorylcholine (2-lyso-PAF) generated from 1-0-alkyl-2-acyl-sn-glyceryl-3-phosphorylcholine by phospholipase A2 (PLA2) activity. Porins and LPS, indeed, induced PLA2-dependent mobilization of [14C]-arachidonic acid that was inhibited by p-bromodiphenacylbromide (PBDB). PBDB, an inhibitor of PLA2, also blocked PAF synthesis by preventing the mobilization of 2-lyso-PAF, the substrate for PAF-specific acetyltransferase.(ABSTRACT TRUNCATED AT 250 WORDS)     

白细胞介素-13功能研究进展

白细胞介素－13主要由活化的Th2(CD4^ )细胞分泌，诱导单核巨噬细胞分化及延长寿命；促进MHC－Ⅱ，CD23表达；抑制炎性和趋化因子产生；诱导B细胞增殖，活化，刺激IgM,IgG的产生和重链的转换；使血管细胞粘附分子－1表达；抑制人类免疫缺陷病毒（HIV）复制；间接诱导巨噬细胞和NK细胞参与抗肿瘤作用。在变态反应性疾病和哮喘中引起呼吸道高反应性，嗜酸粒细胞性炎症，粘液分泌过多，基膜纤维化等，其受体是与IL－4Rα形成功能复合体而发挥作用。IL－13信号转导途径除了JAK／STAT6以外，尚有IRS－1,Fes，磷酸激酶，BCL－6／SOCS等途径。     

QuickVue Influenza Test for Rapid Detection of Influenza A and B Viruses in a Pediatric Population

The performance of a lateral-flow immunoassay, the QuickVue Influenza Test, for detection of influenza A and B viruses in comparison with that of cell culture was evaluated by using nasopharyngeal aspirates, in viral transport medium, from children with respiratory tract infections. The sensitivity and specificity were 79.2 and 82.6%, respectively.     

Fibromyalgia syndrome: the beneficial effects of exercise.

This article highlights positive outcomes for a convenience sample of six women (49-64 years of age) with fibromyalgia syndrome (FMS) who participated in an exercise program over 5 years. This group showed improvement with various FMS symptoms,fitness, and psychosocial factors early in the program, then showed further improvement as a result of adding new exercises to the protocol during the fourth and fifth years. Data suggest that certain people with FMS can improve their functional capacity with exercise over time, and move to even higher levels of physical function while aging and coping with FMS. Practical advice is provided for rehabilitation nurses regarding exercise and FMS.     

Spontaneous angina caused by spasm of the left coronary artery]

A 42 year old woman presented with a one year history of retrosternal chest pain and back pain on effort and at rest sometimes accompanied by minor syncopal attacks. Transient atrioventricular block was documented during one such episode associated with hypotension. Coronary angiography showed spontaneous spasm of the left main coronary artery with clinical symptoms but no electrocardiographic changes. The spasm was relieved by injection of SIN-1. The similarity between the previous clinical symptoms and those observed at coronary angiography was in favour of the diagnosis of spasm of the left main coronary artery without atherosclerotic coronary disease. Treatment with calcium atherosclerotic coronary disease. Treatment with calcium blockers and platelet antiaggregants led to total regression of her symptoms with a follow-up of 5 months.