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991.
SD大鼠羊水间充质干细胞向神经样细胞体外诱导分化   总被引:1,自引:0,他引:1  
目的:探讨体外诱导羊水间充质干细胞(AF-MSCs)分化成神经干细胞.方法:10只SD怀孕大鼠,180-240 g,胎龄16d,过量腹腔麻醉致死,开腹全部切除子宫,在无菌的条件下抽取全羊水,采用贴壁法分离AF-MSCs,体外培养扩增,观察细胞生长特性,流式细胞仪检测AF-MSCs表面抗原表达及细胞周期.取第3代AF-MSCs,加入预诱导液(DMEM/F12、100 mL/L FBS、1 mmol/Lβ-MEM)诱导24 h,然后加入诱导液(DMEM/F12、100 mL/L FBS、5 mmol/L β-MEM)诱导24 h,最后在分化维持培养液(DMEM/F12、20μg/L EGF、20μg/L bFGF)中培养,行免疫荧光染色,检测NSE和GFAP的表达.结果:成功分离、培养和传代SD大鼠AF-MSCs,流式细胞术检测提示大鼠AF-MSCs的G0/G1期细胞比例约为87.5%、S+G2+M期比例为12.5%,表达CD44为98.3%、GD29为70%、和CD105为33.2%、不表达CD45为0.5%,CD34为1%,DLA-DR(MHC class Ⅱ)为0.1%.诱导后,AF-MSCs能表达神经细胞标示物NSE和GFAP,且可在体外继续存活2 wk左右.结论:羊水中也存在MSCs,与其他来源的MSCs特点相符:羊水可以作为一种新的胎儿MSCs来源,而且能在体外诱导分化为神经细胞.  相似文献   
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Monitoring and evaluation of programme to eliminate lymphatic filariasis (LF) depends on epidemiological assessment using appropriate indicators. Minimum efforts using reliable tests are necessary to guide the programme managers in decision-making. Impact of Mass Drug Administration (MDA) towards filariasis elimination can be assessed by the detection of microfilariae (mf) or parasite DNA (infective), filarial antigens (infected) and antibodies (exposure). It is also important to monitor drug resistance and variation in genetic structure of parasite populations using molecular markers. We developed a method to carry out parasitological, molecular, immunological and genetic analysis from a minimum volume of blood sample (about 150 μl) drawn from finger tip of an individual residing in LF endemic area. The method involves separation of sera for immunological assays and isolation of mf of Wuchereria bancrofti from the blood clots for counting, which were then used for W. bancrofti specific PCR, screening for albendazole sensitivity/resistance alleles by AS-PCR, RAPD profiling and ITS 2 PCR for genotyping. A protocol is also suggested for the separation of sera for assays to detect antigen and antibodies and isolation of mf from clots for genetic analysis. The protocol developed has shown potential application in monitoring several immunological, parasitological and molecular parameters from a limited amount of blood sample collected by finger prick, in large-scale operations.  相似文献   
996.
目的:分析自身免疫性溶血性贫血(AIHA)患者血液中红细胞相关抗体(EAIg)免疫分型的临床意义。方法;采用流式细胞仪和抗人单克隆抗体检测24例AIHA患者的EAIg,并分析其亚型及其与临床的关系。结果:24例AIHA患者直接抗人球蛋白试验(Coombs)仅8例阳性,阴性16例,而FCM检测出其中13例EAIg阳性,类型分布以IgG+C3型多见,且贫血、溶血程度重,余依次为C3型、IgG型。结论:AIHA免疫分型可判定疾病的严重程度以及为临床治疗提供依据。  相似文献   
997.
AIMS: Recently, markers of inflammation, haemostasis, and blood rheology have received much attention as risk factors for coronary heart disease and stroke. However, their role in peripheral arterial disease (PAD) is not well established and some of them, including the pro-inflammatory cytokine interleukin-6 (IL-6), have not been examined before in prospective epidemiological studies. METHODS AND RESULTS: In the Edinburgh Artery Study, we studied the development of PAD in the general population and evaluated 17 potential blood markers as predictors of incident PAD. At baseline (1987), 1519 men and women free of PAD aged 55-74 were recruited. After 17 years, 208 subjects had developed symptomatic PAD. In analysis adjusted for cardiovascular risk factors and baseline cardiovascular disease (CVD), only C-reactive protein, fibrinogen, lipoprotein (a), and haematocrit [hazard ratio (95% CI) corresponding to an increase equal to the inter-tertile range 1.30 (1.08, 1.56), 1.16 (1.05, 1.17), 1.22 (1.04, 1.44), 1.22 (1.08, 1.38)] were significantly (P < 0.01) associated with PAD. However, these markers provided very little prognostic information for incident PAD to that obtained by cardiovascular risk factors and the ankle brachial index. Other markers including IL-6, intracellular adhesion molecule 1, d-dimer, tissue plasminogen activator antigen, and plasma and blood viscosities showed weak associations, which were considerably attenuated when CVD risk factors were accounted for. CONCLUSIONS: Our prospective data showed that several inflammatory, haemostatic, and rheological markers are associated with incident PAD; however, their clinical utility is likely to be limited. Future research is necessary to validate the importance of these biomarkers explicitly on PAD and to address the causality of the reported associations.  相似文献   
998.
Aims/hypothesis To test the hypothesis that adipose tissue lipolysis is enhanced in patients with Type 2 diabetes mellitus, we examined the effect of exercise on regional adipose tissue lipolysis and fatty acid mobilisation and measured the acute effects of exercise on the co-ordination of adipose tissue and splanchnic lipid metabolism.Methods Abdominal, subcutaneous adipose tissue and splanchnic lipid metabolism were studied by conducting measurements of arterio-venous concentrations and regional blood flow in six overweight Type 2 diabetic subjects before, during and after exercise.Results Exercise induced an increase in adipose tissue lipolysis and fatty acid release. However, the increase in adipose tissue blood flow was small, limiting fatty acid mobilisation from this tissue. Some of the fatty acids were released in excess in the post-exercise phase. The splanchnic fatty acid uptake was unchanged during the experiment but splanchnic ketogenesis increased in the post-exercise phase. The arterial glucose concentration decreased during exercise and continued to decrease afterwards, indicating an imbalance between splanchnic glucose production and whole-body glucose utilisation.Conclusions/interpretation Regional subcutaneous, abdominal adipose tissue lipolysis is no higher in patients with Type 2 diabetes than in young, healthy subjects. Exercise stimulates adipose tissue lipolysis, but due to an insufficient increase in blood flow, a high fraction of the fatty acids liberated by lipolysis cannot be released to the blood. Splanchnic glucose release is smaller than whole-body glucose utilisation during exercise and post-exercise recovery.Abbreviations ICG indocyanine green - 3-OHB 3-hydroxybutyrate - TAG triacylglycerol - VO2,max peak oxygen consumption  相似文献   
999.

Introduction

The migration of African populations to Europe poses problems of adaptation that may increase the risk of cardiovascular disease. We assessed the cardiovascular risk of Cape Verdean university students studying in Portugal (CV-PT) compared to Cape Verdean university students in Cape Verde (CV-CV) and to Caucasian university students in Portugal (PT-PT).

Methods

A cross-sectional study was performed comparing three university populations, 54-62% female, aged 19-28 years: CV-PT (n=104), CV-CV (n=100) and PT-PT (n=100). Anthropometric data, blood pressure (BP), pulse wave velocity (PWV), albuminuria and estimated 24-h urinary sodium excretion (UNa+) using the Kawasaki formula were measured.

Results

The CV-PT group had higher body mass index and sodium intake (UNa+: CV-PT 235±91, CV-CV 197±85, PT-PT 194±90 mmol/24 h; p<0.001), more sedentary lifestyles and worse socioeconomic, integration and adaptation indices compared to CV-CV and PT-PT. CV-PT and CV-CV also had higher systolic BP (CV-PT 119±12 mmHg, CV-CV 121±15 mmHg, PT-PT 107±14 mmHg; p<0.001), PWV (CV-PT 8.7±1.1, CV-CV 8.8±1.8, PT-PT 8.0±1.2 m/s; p<0.04), and albuminuria (CV-PT 13.0±34.1, CV-CV 9.2±21.2, PT-PT 5.7±6.4 μg/mg creatinine; p<0.04).

Conclusion

Cape Verdean university students in Portugal (CV-PT) have higher albuminuria, BP and PWV values than PT-PT and CV-CV students, associated with less healthy lifestyles, higher cardiovascular risk and worse socioeconomic conditions. The higher cardiovascular risk in these African immigrants means that it is important to implement measures to address modifiable risk factors, to improve integration and to promote healthy lifestyles.  相似文献   
1000.
目的:观察应用输血治疗的恶性血液病化疗患者外周血T细胞亚群及NK细胞活性,探讨去白细胞输血对恶性血液病患者免疫活性细胞的影响。方法:将120例化疗期间需要接受输血治疗的恶性血液病患者分为2组:A组59例接受去白细胞输血;B组61例接受常规输血。2组每次的输血量、输血次数及化疗方案基本相同。对2组治疗前后的T细胞及NK细胞活性进行检测,并与对照组进行比较。结果:①恶性血液病患者各项免疫活性细胞表达均低于对照组(P〈0.01);②治疗前A、B2组免疫活性细胞表达差异无统计学意义,治疗后A组的NK细胞活性明显高于B组(P〈0.01);A组治疗后CD^3-、CD4^+、CD4^+/CD8^+、NK细胞活性明显高于治疗前(P〈0.05);③B组发生非溶血性发热反应(NHFTR)率明显高于A组(P〈0.01)。结论:T细胞亚群、NK细胞活性在恶性血液病患者中受到明显抑制;与常规的输血治疗方法相比,去白细胞输血能明显改善恶性血液病患者的细胞免疫功能,尤其是对NK细胞,并能有效预防NHFTR。  相似文献   
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