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1.
BACKGROUND: Decreased plasma adiponectin is associated with impaired endothelial function and, thereby, increased risk for cardiovascular events. Glucocorticoid (GC) affects vascular endothelial cells either favourably or harmfully depending upon the dosages and duration. We examined the effect of GC pulse therapy on vascular endothelial function. METHODS: Fourteen young patients with IgA nephropathy were evaluated for flow-mediated vasodilation (FMD), plasma levels of adiponectin both in high molecular weight (HMW adiponectin) form and in single molecular form (total adiponectin), hepatocyte growth factor (HGF), asymmetric dimethylarginine (ADMA), and high-sensitive C-reactive protein, before and after a course of GC pulse therapy. RESULTS: GC pulse therapy significantly decreased FMD (from 7.2 +/- 2.6 to 5.7 +/- 2.5%, P < 0.01). Meanwhile, plasma adiponectin levels were significantly augmented (total adiponectin: from 10.2 +/- 4.0 to 12.1 +/- 6.3 microg/ml, P < 0.05; HMW: from 6.5 +/- 3.2 to 7.7 +/- 3.3 microg/ml, P < 0.05). In parallel, elevated concentrations of serum HGF (from 0.28 +/- 0.12 to 0.63 +/- 0.38 ng/ml, P < 0.01) and plasma ADMA (from 0.45 +/- 0.07 to 0.53 +/- 0.04 nmol/ml, P < 0.05) were observed. CONCLUSIONS: GC pulse therapy impaired endothelial function while increasing plasma adiponectin levels, which may in turn restore the endothelial function in patients with IgA nephropathy.  相似文献   
2.

Aims

We explored the effect of remote ischaemic conditioning (RIC) on endothelial function and on circulating mediators.

Methods and results

In 20 healthy male volunteers (mean age 31?±?10 years), flow-mediated dilation (FMD) was measured before and after 20?min of arm ischaemia, followed by reperfusion. Remote ischaemic conditioning (RIC) was performed by applying 3 cycles of 5?min of ischaemia of the leg at the onset of index arm ischaemia. Each volunteer underwent the IR-induced vascular injury protocol with and without RIC in a crossover study design.In the control group, IR significantly reduced FMD (5.9?±?2.9% before IR vs. 2.2?±?3.7% after IR; p?<?0.001). This effect was significantly attenuated by performing RIC (FMD of 5.5?±?3.1% before IR vs. 4.0?±?3.4% % after IR; p for interaction?=?0.01). Serum levels of SOD and ADMA increased significantly whereas MCP-1 and VEGF levels decreased significantly.Only changes in SOD levels were significantly related to the degree of RIC induced protection (r²?=?0.34; p?=?0.018).

Conclusion

RIC has protective effects against endothelial IR injury. Our biomarker study suggests that anti-oxidative stress mediators, such as SOD, seem to be more involved in the pathogenesis of RIC-induced protection in humans than angiogenesis factors or chemo-attractant cytokines.  相似文献   
3.
目的探讨冠心病患者不对称二甲基精氨酸(ADMA)和同型半胱氨酸(Hcy)对一氧化氮合酶(NOS)和一氧化氮(NO)的影响。方法冠心病患者60例和健康体检者30例,测定其ADMA、Hcy、NOS和NO以及血糖、血脂等。结果冠心病组和对照组的ADMA分别为(1.30±0.58)μmol/L和(0.57±0.18)μmol/L、Hcy分别为(31.53±13.26)μmol/L和(20.98±6.39)μmol/L、NOS分别为(5.06±1.82)μ/mg蛋白和(7.03±1.37)μ/mg蛋白、NO分别为(2.56±0.95)nmol/L和(4.21±1.12)nmol/L,两组之间的差异显著(P<0.01)。经相关分析,NOS和NO分别与ADMA和Hcy呈负相关(P<0.05)。结论冠心病患者ADMA和Hcy显著增高,NOS活性降低和NO水平下降与ADMA和Hcy增高有关。  相似文献   
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5.
不对称二甲基精氨酸与动脉粥样硬化   总被引:1,自引:1,他引:1       下载免费PDF全文
不对称二甲基精氨酸与动脉粥样硬化@李建芝$暨南大学医学院组胚教研室!广东广州510632 @常青$暨南大学医学院组胚教研室!广东广州510632不对称二甲基精氨酸;;一氧化氮合酶;;一氧化氮;;动脉硬化~~~~  相似文献   
6.
目的:探讨氧化型—低密度脂蛋白(ox—LDL)对体外培养的人脐静脉内皮细胞(HUVECs)培养液中内源性一氧化氮合酶抑制剂一不对称二甲精氨酸(ADMA)的影响及尼莫地平的干预作用。方法:采用改良的Jaffe法原代培养人脐静脉内皮细胞(HUVECs),取3-6代HUVECs用于实验。用Cu^ 引发脂质过氧化过程,制备氧化型低密度脂蛋白。按实验要求加入不同浓度的ox—LDL和尼莫地平,与内皮细胞共同孵育(37℃,5%CO^2)24h后,收集细胞及培养液。高效液相色谱法(HPLC)测定ADMA、L—arg的浓度。流式细胞仪测定细胞内Ca^ 含量,同时测定培养液NO、ET含量。结果:与空白对照组比较,ox—LDL使HUVECs产生ADMA的量呈浓度依赖性增加,ET及细胞内Ca^ 量显著升高;而合成NO的量减少。尼莫地乎能显著减少ox—LDL诱导的ADMA增加,增加N0的合成,同时细胞内Ca^ 含量及CT降低,而合成N0的底物L-arg无明显变化。结论:ox—LDL增加内源性NOS抑制剂—ADMA的产生,导致内皮细胞的功能障碍。尼莫地平能减少ox—LDL诱导的ADMA增加,从而减轻ox—LDL诱导的内皮细胞代谢功能障碍。  相似文献   
7.
程迎  高晓平  陈和木  张旭 《安徽医学》2019,40(12):1319-1322
目的比较手部外骨骼机器人辅助双侧对称性训练与镜像疗法对脑卒中偏瘫患者手功能的康复效果。方法选取2018年6月至2019年7月在安徽医科大学第一附属医院康复医学科住院的脑卒中偏瘫患者36例,采用随机数字表法分为外骨骼组与镜像组,每组18例。外骨骼组患者利用手部外骨骼机器人进行双手同步对称性训练,镜像组给予镜像疗法。观察两组患者治疗前后手功能及日常生活活动能力的变化,比较两组患者治疗方法的疗效差异。结果治疗后,两组患者Fugl-meyer运动功能量表评分(FMA)及改良Barthel指数均较治疗前提高,差异有统计学意义(P<0.001)。治疗后,外骨骼组患者的FMA评分高于镜像组,差异有统计学意义(P=0.034)。治疗2周后,外骨骼组患者治疗有效率高于镜像组,差异有统计学意义(P=0.044),两组患者治疗显效率差异无统计学意义(P>0.05);治疗3、4周后,两组患者治疗有效率差异均无统计学意义(P>0.05),外骨骼组治疗显效率高于镜像组,差异均有统计学意义(P=0.035,P=0.022)。结论基于手部外骨骼机器人的双侧对称性训练能加速脑卒中患者手功能的恢复进程,对于手功能的改善程度优于镜像疗法。  相似文献   
8.
Asymmetric dimethylarginine (ADMA) is a naturally occurring amino acid found in tissues and cells that circulates in plasma and is excreted in urine. It inhibits nitric oxide synthases (NOs) and produces considerable cardiovascular biological effects. Several studies have suggested that plasma concentrations of ADMA provide a marker of risk for endothelial dysfunction and cardiovascular disease. In animal and in population studies ADMA has been associated with progression of CKD. Several mechanisms may be involved in this association, such as compromise of the integrity of the glomerular filtration barrier and development of renal fibrosis. This review summarizes the existing literature on the biology and physiology of ADMA focusing on its role in the progression of renal disease.  相似文献   
9.
Distal symmetric polyneuropathy (DSPN) is the most common chronic complication of diabetes mellitus. The pathogenesis of DSPN is not fully elucidated, but it is certainly multifactorial in nature and attributable to metabolic and microvessel disorders related to chronic hyperglycemia, diabetes duration, and several cardiovascular risk factors. Early diagnosis and appropriate management are extremely important, since up to 50% of DSPN cases may be asymptomatic, and patients are unaware of foot injury leading to foot ulcers and amputation. Simple, validated tests such as the Neuropathy Disability Score and/or Vibration Perception Threshold may be used to diagnose DSPN. Similarly, neurological dysfunction screening questionnaires should be used to assess the quality and severity of DSPN symptoms. Using both methods enables prediction of the prognosis of diabetic patients with DSPN. No causative treatment of DSPN is known, but the results of clinical trials indicate that several treatment options are highly effective in symptomatic treatment of painful DSPN. The appropriate treatment of DSPN may improve the outcome, preventing or delaying the development of numerous diabetic complications.  相似文献   
10.
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