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71.
力竭运动大鼠心室肌蛋白质组表达特征 总被引:3,自引:0,他引:3
目的:采用蛋白质组学技术,建立安静和递增运动负荷训练后力竭大鼠心室肌蛋白质组的差异性表达谱,初步筛选出心室肌对力竭运动产生反应的目标蛋白质。方法:实验于2007-03在湖南师范大学生命科学学院蛋白质化学与蛋白质组学国家教育部重点实验室和省级运动人体科学实验室完成。①实验分组:10只SD雄性大鼠随机分为对照组和运动组,每组5只。②实验方法:运动组经过7周的大强度递增运动负荷训练后(最后一次力竭),对两组心室肌组织的全蛋白进行双向凝胶电泳分离。结果:经图像分析,在运动组的电泳图谱上共展现蛋白质点(338±17)个,对照组展现蛋白质点(352±17)个。运动后差异表达的蛋白质点共有99个。对其中差异表达的9个蛋白质点进行质谱鉴定,共鉴定出7个蛋白质,Stress-70protein,NADH-ubiquinone oxidoreductase Mr75000subnunit,Long-chain specific acyl-CoA dehydrogenase,Tropomyosin-1alphachain在运动后"缺失",Nitrilase family,member2在运动后表达上调在5倍以上,一个相对分子质量为21000的未知蛋白在运动后表达下调在5倍以上,另外有两个点经鉴定均为Myosin-6,在运动后表达量相反。这些蛋白质属于收缩蛋白、能量代谢酶、分子伴侣等。结论:递增运动负荷训练后力竭时,大鼠心室肌蛋白质组明显地发生了反应。运动后"缺失"和下调的蛋白质点与心肌收缩的调控和能量代谢的方式转变以及细胞的应激反应有关,其中,成功筛选出6种在运动医学领域尚未涉足的、具有运动应激特点的目标蛋白质。 相似文献
72.
肺源性心脏病急性发作期免疫功能的改变 总被引:3,自引:0,他引:3
目的:观察肺源性心脏病(简称肺心病)急性发作期患者免疫功能的变化。方法:选择南华大学附属第一医院2004-11/2006-01收治慢性肺心病急性发作期患者60例为肺心病组,于急性加重期入院第2天7:00,空腹抽取静脉血,采用流式细胞仪检测T细胞亚群CD3 、CD4 、CD8 及自然杀伤细胞活性,免疫浊度法检测体液免疫指标(IgG,IgM,IgA及补体C3)。以同期60例健康体检者为对照。结果:120例是否受试者均进入结果分析。①T细胞亚群:肺心病组CD3 ,CD4 水平低于对照组(0.52±0.06,0.62±0.04;0.32±0.06,0.41±0.06;P均<0.05),CD4 /CD8 高于对照组(1.96±0.26,1.84±0.78,P<0.05)。②免疫血清指标:肺心病组IgA、补体C3及自然杀伤细胞活性低于对照组[(1.26±0.74),(2.45±0.85)g/L;(6200±217),(9960±302)mg/L;0.34±0.08,0.57±0.07;P均<0.05]。结论:肺源性心脏病急性发作期患者的细胞免疫和体液免疫功能均受损,尤以细胞免疫功能受损更突出,且与病情呈平行关系。 相似文献
73.
Histamine levels in stored platelet concentrates. Relationship to white cell content 总被引:1,自引:0,他引:1
The histamine levels in samples from platelet concentrates (PC) were measured at various storage times by a radioenzymatic assay. Elevated histamine levels were detected in 5 of 14 PC after 3 days of storage (range, less than 1 to 13.3 ng/ml) and in 9 of 14 PC after 5 days (range, less than 1 to 22.2 ng/ml). A very good linear correlation (r = 0.913) was found between the initial white cell content of the PC and the histamine level at 5 days of storage. The rise in histamine content was not influenced by the type of plastic container. The results indicate a process of histamine release by the white cells during storage. Although histamine is metabolized rapidly in vivo, a critical histamine threshold could be reached in man by the rapid infusion of stored PC containing high levels of histamine. This could explain some unexpected transfusion reactions in patients receiving PC. 相似文献
74.
Walker AS; Peto TE; Babiker AG; Darbyshire JH 《QJM : monthly journal of the Association of Physicians》1998,91(6):423-438
The Concorde trial compared immediate (Imm) with deferred (Def) AZT
monotherapy in asymptomatic HIV-positive participants. Haematological and
immunological markers and weight were measured throughout, and correlated
with clinical endpoints. Markers associated with disease progression (CD4
lymphocyte count and percentage, platelets, p24 antigen and beta 2
microglobulin favoured Imm: those associated with toxicity (haemoglobin,
neutrophils and white cell count) favoured Def. CD8 and total lymphocyte
count did not differ significantly between groups. In multivariate
analysis, the combination of baseline CD4, p24 antigen and beta 2m was the
best baseline predictor of disease. Including change in CD4 and beta 2m at
12 weeks, or changes over follow- up in these markers significantly
improved the fit. Markers were also incorporated into the definition of
'clinical' endpoints. Hazard ratio estimates from end-points that included
CD4 < 50 and CD4 < 25 were closest to those for AIDS or death alone,
but added very few extra events. Use of other landmark CD4 counts (100 or
greater) or relative decreases in counts (25% or more) increased the number
of events, but overestimated the effect of immediate AZT. Although AZT had
a beneficial effect on the surrogate markers of efficacy evaluated, these
changes did not predict clinical outcome, nor could the markers be usefully
incorporated into an endpoint definition.
相似文献
75.
76.
Angela AG van Tilborg Chris H Bangma Ellen C Zwarthoff 《International journal of urology》2009,16(1):23-30
Early detection of bladder cancer and its recurrences is essential for improved prognosis and long-term survival. The detection and follow-up of these patients is currently based on cystoscopy, which is expensive and invasive, and, in most cases, cytology, which is non-invasive but not very sensitive. During recent years, many urine-based tests have been developed and tested in different patient populations. In this review we discuss new developments for biomarkers in bladder cancer that have potential use in surveillance and screening. In almost all publications authors compare sensitivity of the test with a concomitantly executed cystoscopy, for example, determine cross-sectional sensitivity. However, it has also been shown that false positive test results may be followed by a positive cystoscopy in the near future, showing that cystoscopy itself does not provide 100% sensitivity. This suggests that for a proper evaluation of urine-based tests, longitudinal studies should be carried out and the results communicated to the urologist. 相似文献
77.
AG Stewart 《British journal of pharmacology》2009,158(4):933-935
The active resolution of inflammation is recognized as offering new opportunities to generate novel anti-inflammatory agents. The emerging appreciation of the importance of active resolution in regulation of inflammation also creates an imperative to examine developing and existing agents for their potential to influence these pathways. This themed issue of the British Journal of Pharmacology contains papers that discuss the roles of annexin-1, lipoxins and related lipid products of fish oils as well as other mechanisms involved in active resolution and their receptor targets.This article is part of a themed issue on Mediators and Receptors in the Resolution of Inflammation. To view this issue visit http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009 相似文献
78.
Background and purpose:
In the mammalian brain, histaminergic neurotransmission is mediated by the postsynaptic histamine H1 and H2 receptors and the presynaptic H3 autoreceptor, which also acts as a heteroreceptor. The H1 receptor has been implicated in spatial learning and memory formation. However, pharmacological and lesion studies have revealed conflicting results. To examine the involvement of histamine H1 receptor in spatial reference and working memory formation, H1 receptor knockout mice (KO) were tested in the eight-arm radial maze. Previously, we found that the H1 receptor-KO mice showed reduced emotionality when confronted with spatial novelty. As it is known that emotions can have an impact on spatial learning and memory performance, we also evaluated H1 receptor-KO mice in terms of emotional behaviour in the light–dark box.Experimental approach:
Mice lacking the H1 receptor and wild-type mice (WT) were tested for spatial reference and working memory in an eight-arm radial maze with three arms baited and one trial per day. Emotional behaviour was measured using the light–dark test.Key results:
The H1 receptor-KO mice showed impaired spatial reference and working memory in the radial maze task. No significant differences between H1 receptor-KO and WT mice were observed in the light–dark test.Conclusions and implications:
The spatial memory deficits of the H1 receptor-KO mice might be due to the reported changes in cholinergic neurochemical parameters in the frontal cortex and the CA1 subregion of the hippocampus, to impaired synaptic plasticity in the hippocampus, and/or to a dysfunctional brain reward/reinforcement system. 相似文献79.
80.
Patty H Spruit Sabine Siesling Marloes AG Elferink Ernest JA Vonk Carel JM Hoekstra 《Radiation oncology (London, England)》2007,2(1):1-6