Moderate exercise, postprandial lipaemia and triacylglycerol clearance

Moderate intensity exercise reduces postprandial triacylglycerol (TG) concentrations. We tested whether this reflects increased TG clearance. Eight normotriglyceridaemic men, aged 48.3 +/- 7.3 years (mean +/- SD), performed two oral fat tolerance tests (blood samples taken in the fasted state and for six hours after a high-fat meal containing 1.00 g fat, 0.97 g carbohydrate, 58 kJ energy kg-1 fat-free body mass) and two intravenous fat tolerance tests (blood samples in the fasted state and after a bolus injection of Intralipid, 0.1 g fat kg-1 body mass). The afternoon before one oral and one intravenous test, subjects walked briskly for 90 min; no exercise was performed before the control tests. Prior exercise reduced fasting TG concentration similarly in the oral (16 +/- 7 %) (mean +/- SEM) and intravenous (18 +/- 7 %) tests, and reduced postprandial TG concentrations in the oral test by 18 +/- 6 % (all P < 0.05). However, prior exercise did not increase Intralipid clearance (disappearance curve slopes: control, 4.69 +/- 0.49 % min-1; exercise, 4.85 +/- 0.40 % min-1). These data suggest that mechanisms other than increased TG clearance mediate the lower postprandial TG concentrations seen after moderate exercise.     

结肠炎诱发肝脏屏障功能障碍的研究进展

肝脏屏障是肝脏抵御外源性有害物质侵袭的主要结构,在维持肝脏分泌功能,调控胆汁转运及细胞间信息传递中发挥重要作用。内毒素、炎性因子及胆汁酸等诱发肝脏屏障蛋白改变及屏障功能障碍,可能参与结肠炎性肝病发生。探究结肠炎对肝脏屏障的影响及机制,从肝脏屏障角度阐释结肠炎性肝病的发生机制有望为其防治提供线索和依据。     

Gene dosage--limiting role of Aire in thymic expression, clonal deletion, and organ-specific autoimmunity

Inactivation of the autoimmune regulator (Aire) gene causes a rare recessive disorder, autoimmune polyendocrine syndrome 1 (APS1), but it is not known if Aire-dependent tolerance mechanisms are susceptible to the quantitative genetic changes thought to underlie more common autoimmune diseases. In mice with a targeted mutation, complete loss of Aire abolished expression of an insulin promoter transgene in thymic epithelium, but had no effect in pancreatic islets or the testes. Loss of one copy of Aire diminished thymic expression of the endogenous insulin gene and the transgene, resulting in a 300% increase in islet-reactive CD4 T cells escaping thymic deletion in T cell receptor transgenic mice, and dramatically increased progression to diabetes. Thymic deletion induced by antigen under control of the thyroglobulin promoter was abolished in Aire homozygotes and less efficient in heterozygotes, providing an explanation for thyroid autoimmunity in APS1. In contrast, Aire deficiency had no effect on thymic deletion to antigen controlled by a systemic H-2K promoter. The sensitivity of Aire-dependent thymic deletion to small reductions in function makes this pathway a prime candidate for more subtle autoimmune quantitative trait loci, and suggests that methods to increase Aire activity would be a potent strategy to lower the incidence of organ-specific autoimmunity.     

急性心肌梗死患者糖代谢状况分析

目的探讨急性心肌梗死患者的糖代谢状况。方法连续选择自2010年10月～2011年9月在我院住院的235例急性心肌梗死患者为研究对象,无明确糖尿病史的患者在出院前均常规行口服葡萄糖耐量（OGTT）试验,以明确糖代谢状况。结果急性心肌梗死患者中糖尿病患病率为44.7%,糖调节受损患病率为25.1%,总的糖代谢异常患病率为69.8%。除去既往有糖尿病史的患者,新诊断的糖尿病和糖调节受损患病率分别为24.9%和34.1%。结论急性心肌梗死患者中大多数存在糖代谢异常,行OGTT可及早发现糖代谢异常患者。     

重症监护病房病原菌分布及耐药性变迁

目的了解本院重症监护病房（ICU）最近3年来的病原菌分布情况及其抗菌药物耐药性的变化,为临床合理使用抗菌药物提供科学依据。方法对本院2010年1月～2012年8月所有患者的分离菌株进行回顾性调查与分析。结果 ICU感染细菌以革兰阴性杆菌为主,但阳性球菌有上升趋势,阴性杆菌分离菌种从肺炎克雷伯菌转为鲍曼不动杆菌,阳性球菌以金黄色葡萄球菌为主,两者增加的均是高耐药菌株。肺炎克雷伯菌对亚胺培南、鲍曼不动杆菌对米诺环素、阳性球菌对万古霉素保持高度的敏感性。结论 ICU分离出的细菌以多重耐药菌株增加为主,应加强监测,临床医生应结合本地区细菌流行特点,合理选用抗生素。     

基因芯片技术在结核分支杆菌耐药突变基因检测中的应用

目的通过基因芯片检测系统，快速检测临床样品中结核分支杆菌耐药突变情况。方法根据结核分支杆菌标准株H37Rv序列，设计了覆盖rpoB、katG，inhA基因突变区的系列寡核苷酸探针，制作膜芯片，检测临床样品中结核分支杆菌基因突变情况，以此判断耐药结果。结果在305例临床病例中，共检出阳性病例125例，其中阳性敏感病例64例，阳性突变病例61例，阳性率为40．98％，在125例阳性样品中，共发现有8种突变类型，其中10例531L，占7．94％，19例315M，占阳性样品中总数的15．08％。结论PCR与膜芯片杂交技术可临床检测结核分支杆菌对利福平和异烟肼的耐药性，并具有快速、简便、敏感的特点。     

Influenza virus-induced dendritic cell maturation is associated with the induction of strong T cell immunity to a coadministered,normally nonimmunogenic protein

We evaluated the proposal that during microbial infection, dendritic cells (DCs) undergo maturation and present a mixture of peptides derived from the microbe as well as harmless environmental antigens. Mice were exposed to an aerosol of endotoxin free ovalbumin (OVA) in the absence or presence of influenza virus. In its absence, OVA failed to induce B and T cell responses and even tolerized, but with influenza, OVA-specific antibodies and CD8+ cytolytic T lymphocytes developed. With or without infection, OVA was presented selectively in the draining mediastinal lymph nodes, as assessed by the comparable proliferation of infused, CD8+ and CD4+, TCR transgenic T cells. In the absence of influenza, these OVA-specific T cells produced little IL-2, IL-4, IL-10, and IFN-gamma, but with infection, both CD4+ and CD8+ T cells made high levels of IL-2 and IFN-gamma. The OVA plus influenza-treated mice also showed accelerated recovery to a challenge with recombinant vaccinia OVA virus. CD11c+ DCs from the mediastinal lymph nodes of infected mice selectively stimulated both OVA- and influenza-specific T cells and underwent maturation, with higher levels of MHC class II, CD80, and CD86 molecules. The relatively slow (2-3 d) kinetics of maturation correlated closely to the time at which OVA inhalation elicited specific antibodies. Therefore respiratory infection can induce DC maturation and simultaneously B and T cell immunity to an innocuous antigen inhaled concurrently.     

Lipid and carbohydrate metabolism in uraemia

Lipid and carbohydrate metabolism variables were studied in twenty-eight patients with chronic renal failure (mean GFR 7.7 +/- 2.5 ml/min) and uraemic symptoms. 71% of the patients had hypertriglyceridaemia (greater than or equal to 2.2 mmol/l). Total serum cholesterol was normal while VLDL cholesterol was high and alpha-lipoprotein cholesterol was low. The fractional elimination rate of Intralipid was low and inversely correlated to serum triglyceride levels. Intravenous glucose tolerance was reduced with normal or slightly increased fasting blood glucose and insulin values before and during the test. Serum triglycerides were correlated to plasma insulin but not to residual renal function or serum urea levels. The cause of hypertriglyceridaemia and lowering of alpha-Lp cholesterol is not unequivocally clear. Present evidence indicate that retarded catabloism of triglyceride-rich lipoproteins is important but accentuated release of triglyceride-rich lipoproteins may have occurred in a number of cases. The commonly used treatment with beta-blocking agents for hypertension in chronic renal failure may accentuate certain of the metabolic responses in uraemia.     

胃肠耐受性监测对急性脑血管病患者治疗转归的影响

目的探讨胃肠耐受性监测对急性脑血管病患者治疗转归的影响。方法将170例急性脑血管病患者随机分为观察组(90例)及对照组(80例),两组均常规予控制颅内压、营养神经、调整血糖血压、改善脑循环、防治并发症治疗,按急性脑血管病常规护理,密切监测生命体征、意识、瞳孔,观察组增加胃肠耐受性监测。观察比较两组并发症的发生率及住院时间。结果观察组并发症的发生率为18%,显著低于对照组42%(P<0.05);观察组住院时间(23.99±6.15)d比对照组(27.25±6.54)d明显缩短(t=3.35,P<0.05)。结论急性脑血管病患者,在常规护理同时,还应进行胃肠耐受性监测,及早改善胃肠功能,降低并发症的发生率,使患者获得更好的治疗转归,缩短住院时间。     

免疫耐受标志物在器官移植中的研究进展

尽管器官移植在过去的50余年中取得了明显进步,但免疫抑制剂应用带来的相关不良反应是影响移植受体长期存活的因素之一,免疫耐受是解决这一问题的关键.近年来,临床上发现部分器官移植受体发生了临床免疫耐受.研究发现,外周血中调节性T淋巴细胞、B淋巴细胞数量和部分基因表达在肾移植免疫耐受者有明显差异;外周血中调节性T淋巴细胞、树突状细胞、γδTCR+T淋巴细胞数量和部分基因表达在肝移植免疫耐受者有明显差异,提示上述指标作为器官移植免疫耐受标志物的潜在价值.MicroRNA由于其在免疫系统中的重要作用,初步研究提示其可作为潜在的免疫耐受标志物.