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Pieces of the preeclampsia puzzle.   总被引:1,自引:0,他引:1  
Introduction Several interesting articles have been published recently thataddress novel mechanisms for preeclampsia. These mechanismsall involve circulating factors, a favourite topic for preeclampsiaresearchers. These factors may interfere with angiogenesis,engage angiotensin (Ang) II signalling, and directly impairendothelial function. VEGF, PlGF and sFlt1 Vascular endothelial growth factor (VEGF) must be very busyduring pregnancy. The growth factor’s receptor, fms-liketyrosine kinase 1 (Flt1), exists in two forms, namely a membrane-boundreceptor tyrosine kinase that transmits angiogenic signals anda soluble secreted ectodomain (sFlt1), which may capture VEGFand keep the growth factor from its active bound receptor. Maynardet al. [  相似文献   
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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   
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低浓度乙醇对血管内皮细胞损伤的保护作用   总被引:2,自引:0,他引:2  
目的研究乙醇对氧化低密度脂蛋白(ox-LDL)诱导的人脐带静脉内皮细胞损伤的保护作用与内源性一氧化氮合酶抑制物的关系。方法在培养的人脐带静脉内皮细胞中加入ox-LD(L100μg/ml)诱导内皮细胞损伤。检测细胞培养液中非对称性二甲基精氨酸(ADMA)、丙二醛(MDA)、乳酸脱氢酶(LDH)、一氧化氮(NO)和肿瘤坏死因子-(αTNF-α)的含量。结果体外给予ox-LD(L100μg/ml)显著诱导内皮细胞损伤,增加培养液中ADMA、MDA、LDH和TNF-α水平,而降低NO水平。两个剂量乙醇(5或15μg/ml)均能显著抑制ox-LDL所致ADMA、MDA、LDH和TNF-α浓度升高和NO的降低。结论低剂量乙醇对ox-LDL诱导的人脐带静脉血管内皮细胞损伤有保护作用,其保护作用与降低ADMA和TNF-α浓度有关。  相似文献   
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Objective

The beneficial effects of fish and n-3 polyunsaturated fatty acids (PUFAs) consumption on atherosclerosis have been reported in numerous epidemiological studies. However, to the best of our knowledge, the effects of a fish-based diet intervention on endothelial function have not been investigated. Therefore, we studied these effects in postmenopausal women with type 2 diabetes mellitus (T2DM).

Materials/Methods

Twenty-three postmenopausal women with T2DM were assigned to two four-week periods of either a fish-based diet (n-3 PUFAs ≧ 3.0 g/day) or a control diet in a randomized crossover design. Endothelial function was measured with reactive hyperemia using strain-gauge plethysmography and compared with the serum levels of fatty acids and their metabolites. Endothelial function was determined with peak forearm blood flow (Peak), duration of reactive hyperemia (Duration) and flow debt repayment (FDR).

Results

A fish-based dietary intervention improved Peak by 63.7%, Duration by 27.9% and FDR by 70.7%, compared to the control diet. Serum n-3 PUFA levels increased after the fish-based diet period and decreased after the control diet, compared with the baseline (1.49 vs. 0.97 vs. 1.19 mmol/l, p < 0.0001). There was no correlation between serum n-3 PUFA levels and endothelial function. An increased ratio of epoxyeicosatrienoic acid/dihydroxyeicosatrienoic acid was observed after a fish-based diet intervention, possibly due to the inhibition of the activity of soluble epoxide hydrolase.

Conclusions

A fish-based dietary intervention improves endothelial function in postmenopausal women with T2DM. Dissociation between the serum n-3 PUFA concentration and endothelial function suggests that the other factors may contribute to this phenomenon.  相似文献   
9.

Aim

The aim of the study was to evaluate the association between high plasma ADMA levels, a biomarker of endothelial dysfunction, with the progression of albuminuria and chronic kidney disease (CKD) in hypertensive patients, with and without type 2 diabetes mellitus.

Methods

We successfully contacted 213 of 644 patients who had been evaluated between 2004 and 2005 and for whom basal data were available. After the exclusion of 51 patients, 162 hypertensive patients who were free from albuminuria were stratified into the following 4 groups according to the presence of diabetes and plasma ADMA percentiles: general hypertensive patients with high levels of plasma ADMA (>P4 or ADMA?>?0.61?μmol/L), general hypertensive patients with low levels of plasma ADMA (≤P4), diabetic hypertensive patients with high levels of plasma ADMA (>P4), and diabetic hypertensive patients with low levels of plasma ADMA (≤P4).

Results

The patients were prospectively evaluated over 5.8?years. High ADMA levels were associated with the progression of albuminuria in hypertensive patients, with and without type 2 diabetes. Major increases in the ADMA value during follow-up were associated with the progression of CKD, and direct correlations between ADMA changes and GFR changes were observed in the whole group and in the subgroup of diabetic patients.

Conclusions

We suggest that high plasma ADMA levels might be a biomarker of renal disease progression and might even be an early predictor of albuminuria and its progression to the late stages of renal disease in hypertensive and diabetic hypertensive patients.  相似文献   
10.
目的:通过观察非对称性二甲基精氨酸(ADMA)对树突状细胞(dendritic cells,DCs)成熟及免疫的影响来探讨AS形成的可能机制。方法:贴壁法分离人外周血单核细胞,在含重组人粒-巨噬细胞集落刺激因子(rhGM-CSF 20ng/ml)和重组人白细胞介素-4(rhIL-4,10ng/ml)的完全培养基中培养,五天后收集imDC,用1、8、16umol/L的ADMA干预未成熟DC 24h。用流式细胞术检测DC细胞表面分子的表达、吞噬能力及DC的凋亡,用混合淋巴细胞反应检测成熟DC刺激T淋巴细胞增殖的能力,用ELISA检测DC细胞因子的分泌。结果:生理浓度ADMA并不刺激DC成熟及分化;但病理浓度ADMA抑制DC成熟;抑制DC诱导的T淋巴细胞增殖;诱导DC凋亡:抑制DC分泌IL-12细胞因子、TNF-α及IL-10细胞因子。结论:生理浓度ADMA并不刺激DC成熟及分化;但病理浓度AD-MA抑制DC成熟和免疫。  相似文献   
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