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21.
以实验性高脂血症大鼠为模型研究了调节源口服液对高脂大鼠红细胞膜流动性、肝匀浆膜流动性的影响。并对血脂、肝脂血浆及肝组织中脂质过氧化物(LPO)加以测定,结果显示:调节源口服液能显著降低血浆、肝组织中胆固醇含量(P<0.01),也同样能显著降低血浆、肝组织中脂质过氧化物的含量(P<0.01),提高了红细胞膜、肝组织匀浆膜流动性。  相似文献   
22.
目的了解来我院体检的辽西地区体检人员的血清总胆固醇(TC)和血清三酰甘油(TG)水平与性别之间的关系。方法对11817例地方体检人员的检查资料进行整理分析,按性别进行分组,分为男性体检人员组(6656例)和女性体检人员组(5161例),用酶法检测体检者TC和TG水平,运用统计学方法(t检验,卡方检验)对检验结果进行调查分析。结果男性体检人员组的TC和TG水平与女性体检人员组的TC和TG水平比较差异均有统计学意义(P<0.05)。男性体检人员组中TC异常的发生率为44.01%(2929/6656),女性体检人员组中TC异常的发生率为28.19%(1455/5161),男性体检人员组的TC异常的发生率和女性体检人员组的TC异常的发生率比较差异有统计学意义(P<0.05)。男性体检人员组中TG异常的发生率为45.43%(3024/6656),女性体检人员组中TG异常的发生率为16.93%(874/5161),男性体检人员组的TG异常的发生率和女性体检人员组的TG异常的发生率比较差异有统计学意义(P<0.05)。结论辽西地区男性的TC和TG水平高于女性,并具有显著性差异。TC和TG异常的发生与性别因素相关。  相似文献   
23.
Mechanistic exploration has pinpointed nanosized extracellular vesicles, known as exosomes, as key mediators of the benefits of cell therapy. Exosomes appear to recapitulate the benefits of cells and more. As durable azoic entities, exosomes have numerous practical and conceptual advantages over cells. Will cells end up just being used to manufacture exosomes, or will they find lasting value as primary therapeutic agents? Here, a venerable natural process—the generation of honey—serves as an instructive parable. Flowers make nectar, which bees collect and process into honey. Cells make conditioned medium, which laboratory workers collect and process into exosomes. Unlike flowers, honey is durable, compact, and nutritious, but these facts do not negate the value of flowers themselves. The parallels suggest new ways of thinking about next-generation therapeutics.  相似文献   
24.
25.
Axonal outgrowth is a fundamental process during the development of central (CNS) and peripheral (PNS) nervous system as well as in nerve regeneration and requires accurate axonal navigation and extension to the correct target. These events need proper coordination between membrane trafficking and cytoskeletal rearrangements and are under the control of the small GTPases of the Rho family, among other molecules. Reelin, a relevant protein for CNS development and synaptic function in the adult, is also present in the PNS. Upon sciatic nerve damage, Reelin expression increases and, on the other hand, mice deficient in Reelin exhibit an impaired nerve regeneration. However, the mechanism(s) involved the Reelin‐dependent axonal growth is still poorly understood. In this work, we present evidence showing that Reelin stimulates dorsal root ganglia (DRG) regeneration after axotomy. Moreover, dissociated DRG neurons express the Reelin receptor Apolipoprotein E‐receptor 2 and also require the presence of TC10 to develop their axons. TC10 is a Rho GTPase that promotes neurite outgrowth through the exocytic fusion of vesicles at the growth cone. Here, we demonstrate for the first time that Reelin controls TC10 activation in DRG neurons. Besides, we confirmed that the known CNS Reelin target Cdc42 is also activated in DRG and controls TC10 activity. Finally, in the process of membrane addition, we found that Reelin stimulates the fusion of membrane carriers containing the v‐SNARE protein VAMP7 in vesicles that contain TC10. Altogether, our work shows a new role of Reelin in PNS, opening the option of therapeutic interventions to improve the regeneration process.  相似文献   
26.
老年高血压患者颈动脉粥样硬化病变及相关因素   总被引:18,自引:0,他引:18  
目的探讨老年高血压患者的颈动脉粥样硬化病变程度及其与血脂、血尿酸、C-反应蛋白的关系。方法应用彩色多普勒超声检测22例正常老年人(对照组)、47例老年高血压患者(A组)、43例老年高血压合并冠心病患者(B组)的颈动脉内中膜厚度(IMT)、粥样硬化斑块、血流参数[收缩期峰值流速(Vmax)、阻力指数(RI)];同时检测血脂、血尿酸(UA)及C反应蛋白(CRP)。结果A组与对照组比较,平均IMT、最大IMT及CRP增高(均为P<0.001),斑块发生率、Vmax、RI、胆固醇(TC)、低密度脂蛋白(LDL-C)、UA增高(均为P<0.05);B组与A组比较,平均IMT、最大IMT、RI及CRP增加更为明显(均为P<0.001),斑块发生率、Vmax、TC、甘油三酯(TG)、LDL-C、UA也有相应变化(均为P<0.05)。结论老年颈动脉粥样硬化病变与许多危险因素有关,防治应采取综合措施。  相似文献   
27.
The purpose of the present study was to investigate hypolipidemic and anti-inflammatory effects of Artemisia vulgaris extract in hypercholesterolemic rats. Hypercholesterolemia was induced by feeding of rats with high fat diet containing 3% cholesterol in olein oil, for 8 weeks. Feeding of rats with high fat diet for 8 weeks, leading to a significant increase in serum triglycerides, total cholesterol, low density lipoprotein cholesterol, malondialdehyde and nitric oxide, tumor necrosis factor-α levels and a significant decrease in serum high density lipoprotein cholesterol level, liver hydroxymethylglutaryl-CoA reductase activity and paraoxonase-1 activities as compared to the normal control group. Treatment of high fat diet rats with Artemisia vulgaris extract for 4 weeks at a dose of 100 mg/kg per day, resulted in normalized serum lipid profile, a significant increase in paraoxonase-1 activity and decrease in serum malondialdehyde, nitric oxide and tumor necrosis factor-α level as compared to high fat diet-treated animals. Also the extract caused a significant decrease in hydroxymethylglutaryl-CoA reductase activity as compared with both high fat diet-treated animals and control ones. In conclusion, Artemisia vulgaris extract has hypolipidemic, anti-inflammatory, antioxidant properties; it may serve as a source for the prevention of atherosclerosis and cardiovascular diseases.  相似文献   
28.
BACKGROUND & AIMS: Hydrophobic bile salts trigger a rapid oxidative stress response as an upstream event of CD95 activation and hepatocyte apoptosis. METHODS: The underlying mechanisms were studied by Western blot, immunocytochemistry, protein knockdown, and fluorescence resonance energy transfer microscopy in rat hepatocytes and human hepatoma cell line 7 (Huh7). RESULTS: The rapid oxidative stress formation in response to taurolithocholate-3-sulfate (TLCS) was inhibited by diphenyleneiodonium, apocynin, and neopterin, suggestive for the involvement of nicotinamide adenine dinucleotide phosphate (NADPH) oxidases. TLCS induced a rapid serine phosphorylation of the regulatory subunit p47phox, which was sensitive to inhibition of sphingomyelinase and protein kinase Czeta (PKCzeta). Inhibitors of p47phox phosphorylation and p47phox protein knockdown abolished the TLCS-induced oxidative stress response and blunted subsequent CD95 activation. Consequences of TLCS-induced oxidative stress were c-Jun-N-terminal kinase activation and Yes-dependent activation of the epidermal growth factor receptor (EGFR), followed by EGFR-catalyzed CD95 tyrosine phosphorylation, formation of the death-inducing signaling complex, and execution of apoptosis. As shown by fluorescence resonance energy transfer experiments in Huh7 cells, TLCS induced a c-Jun-N-terminal kinase-dependent EGFR/CD95 association in the cytosol and trafficking of this protein complex to the plasma membrane. Inhibition of EGFR tyrosine kinase activity by AG1478 allowed for cytosolic EGFR/CD95 association, but prevented targeting of the EGFR/CD95 complex to the plasma membrane. Both processes, and TLCS-induced Yes and EGFR activation, were sensitive to inhibition of sphingomyelinase, PKCzeta, or NADPH oxidases. CONCLUSIONS: The data suggest that hydrophobic bile salts activate NADPH oxidase isoforms with the resulting oxidative stress response triggering activation of the CD95 system and apoptosis.  相似文献   
29.

Aim

To evaluate the serum paraoxonase 1 activity and determine its association with duration in type 2 Diabetes mellitus patients.

Methods

A total of 80 cases from type 2 diabetes mellitus and healthy controls were enrolled in the present case control study. Human serum PON1 concentration was measured by ELISA and western blotting and it activity was determined spectrophotometrically using 4-nitrophenyle acetate. Diagnostic accuracy of serum PON1 to identify type 2 Diabetes mellitus was calculated with ROC analysis.

Result

Serum concentration of LDL, VLDL, TG, A1C, FBS and TC levels showed significantly higher levels in type 2 diabetes patients as compared to healthy controls, however there were no significant differences found in the level of HDL. Serum PON1 concentration and activity monitored in patients with >1?year diabetes showed higher level (75.1?±?6.8?ng/mL) as compared to patients with >3?years diabetes (65.24?±?1.6?ng/mL), its level was further decreased in patients with >5 (53.8?±?2.6?ng/mL) and >7?years (48.1?±?2.7?ng/mL) of diabetes. PON1 concentration decreased as the duration of diabetes increased. PON1 level was further decreased due to habits like smoking and alcohol consumption.

Conclusion

Serum PON1 levels decrease in states of high oxidative stress like metabolic syndrome, obesity, uncontrolled diabetes, and dyslipidemia. It can be used as diagnostic marker for diabetes mellitus along with increased TG, LDL, VLDL and FBG.  相似文献   
30.
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