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31.
Ultraviolet light enhances the generation of reactive oxygen species that are responsible for skin photoageing. The aim of this randomized, vehicle‐ and active‐controlled double‐blind, intra‐individual monocentric study was to evaluate in situ the antioxidant activity of a dermo‐cosmetic product in photoaged skin. Twenty healthy volunteers had defined skin areas randomized to receive a topical product containing 3 antioxidants (pre‐tocopheryl®, retinaldehyde and glycylglycine ole‐amide), its vehicle and a positive antioxidant control cream. The products were applied daily for 30‐day period. The skin areas were exposed to a controlled dose of UVA rays, and the skin oxidative status was evaluated 4 and 24 hours post‐UVA exposure at D0 (basal value) and after 15 and 30 days of product application. Skin layers were collected by stripping, and antioxidant capacity was measured using the ferric reducing ability of a plasma assay. Lipid peroxidation (LPO) was assessed using the malonyldialdehyde test. The tested product significantly improved the skin antioxidant capacity after 15 and 30 days and significantly decreased the basal level of the skin LPO. The skin LPO level significantly decreased 4 and 24 hours after UVA exposure at 15 and 30 days. These findings were comparable to positive control treated sites and were significantly different from the vehicle and untreated sites. This minimally invasive methodology enabled a quantitative evaluation of potent antioxidant activity in situ in the stratum corneum reflecting real‐life skin conditions and confirming the benefits of the topical application of a product containing 3 antioxidants in the prevention of UVA‐induced oxidative damage. 相似文献
32.
In insects, lipid digestion is controversial because insects have no bile salts to solubilize dietary lipids. One hypothesis is that a secretory type of phospholipase A2 (sPLA2) provides lysophospholipid (LPL) from dietary phospholipids (PLs). We identified a sPLA2, Se‐sPLA2, in beet armyworm, Spodoptera exigua, that hydrolyses PLs at sn‐2. Our goal was to investigate its role in lipid digestion. Se‐sPLA2 was expressed in the entire alimentary canal. Incubating the isolated midgut in a cell culture medium led to secretion of Se‐sPLA2 and other proteins. Ex vivo RNA interference (RNAi) of Se‐sPLA2 expression in isolated midgut culture led to significantly decreased Se‐sPLA2 secretion into the medium. Feeding double‐stranded RNA specific to Se‐sPLA2 to larvae suppressed sPLA2 activity in gut contents. A recombinant Se‐sPLA2 was susceptible to benzylideneacetone (BZA), a specific PLA2 inhibitor. After feeding BZA to larvae, we recorded significant decreases in gut content sPLA2 activity, body growth and total haemolymph lipid contents. RNAi against Se‐sPLA2 resulted in reduced digestibility. Addition of a specific LPL, 1‐palmitoyl‐sn‐glycero‐3‐phosphocholine, to BZA‐treated larvae rescued digestibility and larval growth. These results strongly bolster our hypothesis that Se‐sPLA2 secreted from the midgut acts in lipid digestion by providing necessary LPL to solubilize dietary neutral lipids. 相似文献
33.
[目的]通过现代检验技术研究筋疽(糖尿病足非缺血性坏疽)湿热毒盛证的糖脂代谢指标。[方法]收集136例筋疽(糖尿病足非缺血性坏疽)患者进行不同证型间指标的比较。[结果]湿热毒盛证患者空腹血糖(FBG)、糖化血红蛋白(HbA1c)、餐后2 h血糖(2 hPBG)、晚期糖基化终末产物(AGEs)、白蛋白(ALB)、总胆固醇(TC)、高密度脂蛋白(HDL-C)与其他证型比较存在统计学差异(P<0.05)。湿热毒盛证患者C-反应蛋白(CRP)、人可溶性血管细胞黏附分子1(sVCAM-1)与其他证型组间比较存在统计学差异(P<0.01)。[结论]筋疽(糖尿病足非缺血性坏疽)湿热毒盛证形成的原因与低营养状态下糖脂代谢紊乱引起的高血糖及持续炎症反应相关。 相似文献
34.
35.
目的:探讨2型糖尿病(T2DM)患者不同脂质参数与糖尿病肾病(DKD)发生的相关性。方法:检测226例T2DM患者血清TC、TG、LDL-C、HDL-C水平及相关生化指标,计算血浆致动脉硬化指数(AIP)以及脂质三角相关指标(TC/HDL-C、TG/HDL-C、LDL-C/HDL-C)。根据DKD临床诊断标准和Mogensen分期标准分为:Ⅰ~Ⅱ期组136例,Ⅲ期组55例,Ⅳ~Ⅴ期组35例。应用多因素logistic回归分析不同脂质参数与DKD发生的关系。结果:与Ⅰ~Ⅱ期组相比,随着DKD分期加重,TC、TG、LDL-C、LDL-C/HDL-C、AIP水平明显增高(P<0.01)。LDL-C/HDL-C和AIP与24 h尿蛋白水平呈正相关(r=0.724;r=0.769,均P<0.05)。LDL-C/HDL-C和AIP是T2DM合并DKD患者的独立预测因子(P=0.002;P=0.004)。结论:LDL-C/HDL-C和AIP对T2DM合并DKD病情进展有较高的预测价值,可为临床诊治提供参考。 相似文献
36.
目的:探讨舌三针联合康复训练对脑梗死后假性延髓麻痹所致构音障碍疗效,以期提高脑卒中后患者生命质量。方法:选取2016年12月至2019年1月海南省人民医院收治的脑梗死后假性延髓麻痹所致构音障碍患者78例进行回顾性分析,按照治疗方法不同分为对照组和观察组,每组39例。对照组常规西医+康复训练治疗,观察组在以上基础上加用舌三针治疗,均连续治疗6周。观察2组治疗前、完成治疗后血脂、Frenchay构音评分、血液流变学、言语空气动力学指标变化并比较。完成治疗后总结疗效情况。结果:1)2组治疗完成后反射、呼吸、唇、颌、软腭、喉、舌、言语评分和治疗前比较均显著上升(P<0.05),且观察组上升幅度显著高于对照组(P<0.05)。2)2组治疗完成后三酰甘油(TG)、总胆固醇(TC)、低密度脂蛋白(LDL-C)较治疗前均显著下降,高密度脂蛋白胆固醇(HDL-C)较治疗前比较均显著上升(P<0.05),且观察组上升幅度显著高于对照组(P<0.05)。3)2组治疗完成后全血高低切黏度、血浆黏度、红细胞压积较治疗前均显著下降(P<0.05),且观察组优于对照组(P<0.05)。4)对照组治疗前、完成治疗后各指标比较差异无统计学意义(P>0.05),观察组治疗完成后平均声压级(MSDV)、音调(P)、最长发声时间(MPT)、平均气流率(MFR)、声门下压(SGP)、声门阻力(GR)、发声效率(VE)较治疗前均显著升高(P<0.05),且观察组优于对照组(P<0.05)。5)观察组治愈率38.46%、总有效率89.74%,显著高于对照组治愈率23.08%、总有效率79.49%(P<0.05)。结论:舌三针联合康复训练能通过促进脑微循环,改善血脂,促进言语功能来改善脑梗死后假性延髓麻痹所致构音障碍症状,提高生命质量。 相似文献
37.
Iva Justini Ana Kati Deni Uri
i Boena urko‐Cofek Branka Blagovi Gordana anadi Jurei 《Environmental toxicology》2020,35(3):346-358
The yeast Saccharomyces cerevisiae is a useful model for studying the influence of different stress factors on eukaryotic cells. In this work we used the pesticide imidacloprid, in the Confidor formulation, as the stress factor and analyzed its influence on the metabolic activity, proteome and lipid content and composition of Saccharomyces cerevisiae yeast. During the cultivation of yeast, the lowest recommended application dose of Confidor (0.025%, v/v) was added to the growth media and its influence on the mitochondria, cytosol with microsomes, and the whole yeast cells was monitored. The results show that under the stress provoked by the toxic effects of Confidor, yeast cells density significantly decreased and the percentage of metabolically disturbed cells significantly increased comparing with untreated control. Also, there was a downregulation of majority of glycolytic, gluconeogenesis, and TCA cycle enzymes (Fba1, Adh1, Hxk2, Tal1, Tdh1,Tdh3, Eno1) thus providing enough acetyl‐CoA for the lipid restructuring and accumulation mechanism since we have found the changes in the cell and mitochondrial lipid content and FA composition. This data suggest that lipids could be the molecules that orchestrate the answer of the cells in the stress response to the Confidor treatment. 相似文献
38.
目的:观察中药益气活血通络汤治疗高血压合并糖耐量减低的临床疗效。方法:将64例高血压合并糖尿病患者,随机分为2组各32例,对照组口服硝苯地平片治疗;观察组加用中药益气活血通络汤,以治疗前后收缩压(SBP)、舒张压(DBP)、三酰甘油(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)、血糖、胰岛素、胰岛素敏感性指数(ISI)、胰岛素抵抗指数(HOMA-IR)为观察指标。结果:治疗3个月后,观察组疗效优于对照组(Z=-1.998,P<0.05)。与治疗前比较,2组经治疗后SBP、DBP、TC、TG、LDL-C均下降,HDL-C上升,差异有统计学意义(P<0.05);观察组治疗后SBP、DBP、TC、TG、LDL-C、HDL-C与对照组治疗后比较,差异有统计学意义(P<0.05)。与治疗前比较,2组经治疗后空腹和餐后2 h血糖、胰岛素、HOMA-IR均下降,ISI上升,差异有统计学意义(P<0.05);且经治疗后,观察组上述所有指标改善情况均优于对照组,差异有统计学意义(P<0.05)。2组患者在3个月的治疗期间中均未出现严重不良反应。结论:中药益气活血通络汤治疗高血压合并糖耐量降低疗效较好且安全性高,能显著降低血压,改善血脂。 相似文献
39.
Context: Baicalin has many pharmacological activities, including protective function against myocardial ischemia by antioxidant effects and free radical scavenging activity. However, its rapid elimination half-life in plasma and poor water solubility limits its clinical efficacy.Objective: Novel baicalin-loaded PEGylated nanostructured lipid carriers (BN-PEG-NLC) were developed to improve bioavailability of BN, to prolong retention time in vivo and to enhance its protective effect.Methods: In this study, BN-PEG-NLC were prepared by the emulsion-evaporation and low temperature-solidification method using a mixture of glycerol monostearate and polyethylene glycol monostearate as solid lipids, and oleic acid as the liquid lipid. The physicochemical properties of NLC were characterized. The pharmacokinetic and pharmacodynamic behaviors of BN-PEG-NLC or BN-NLC were evaluated in acute MI rats.Results and discussion: The particle size, zeta potential, and entrapment efficiency for BN-PEG-NLC were observed as 83.9?nm, ?32.1?mV, and 83.5%, respectively. The release profiles of BN from both BN-PEG-NLC and BN-NLC were fitted to the Ritger–Peppas modal, which presented burst release initially and prolonged release afterwards. Pharmacokinetics results indicated that BN-PEG-NLC exhibited a 7.2-fold increase in AUC in comparison to BN solution, while a 3-fold increase in comparison to BN-NLC. Biodistribution results revealed that BN-PEG-NLC exhibited higher heart drug concentration compared with BN-NLC as well as BN solution. In the present study, BN-PEG-NLC significantly ameliorated infarct size.Conclusion: The results of the present study imply that PEG-NLC could be the biocompatible carriers for heart-targeted drug delivery to improve myocardial ischemia. 相似文献
40.
《The Journal of emergency medicine》2020,58(2):e47-e50
BackgroundBupropion overdose is a commonly encountered presentation in the emergency department (ED). While the majority of cases resolve with supportive care, serious adverse effects, including seizures, cardiogenic shock, and death, can occur. Intravenous lipid emulsion (ILE) therapy has been utilized for a multitude of poisonings with varying levels of success. Although a number of cases suggest the value of ILE therapy in cases of bupropion overdose, more recent data propose that its role may be overstated.Case ReportA young woman presented to the ED with altered mental status complicated by seizure after bupropion overdose. She subsequently developed cardiogenic shock requiring vasopressor support. Bedside echocardiogram revealed a decreased left ventricular ejection fraction (LVEF). She received ILE therapy with significant improvement in both hemodynamic status and LVEF by bedside ultrasound.Why Should an Emergency Physician Be Aware of This?Although the majority of patients presenting with bupropion overdose improve with supportive care, life-threatening sequelae are possible. ILE therapy has shown promise in a variety of different overdose situations, although the evidence in cases of bupropion poisoning has been varied, and it has traditionally been utilized as a last-line rescue modality. Based on hemodynamic parameters and bedside ultrasound, this case suggests that early initiation of ILE therapy should be considered in these cases, as the potential benefits likely outweigh the theoretical risks. 相似文献