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1.
目的 对比研究朝鲜淫羊藿酸性多糖酯化还原前后的理化特性,并探讨其改善油酸诱导的肝癌HepG2细胞脂质堆积活性的差异。方法 采用高效凝胶渗透色谱法测定朝鲜淫羊藿酸性多糖(EFPA)的均一性和分子量,高效液相色谱法测定EFPA和酯化还原后朝鲜淫羊藿酸性多糖(EFPA-R)的单糖组成;采用油酸(OA)处理HepG2细胞诱导建立脂质蓄积模型,不同浓度EFPA与EFPA-R(10、30、100、300 μg·mL-1)分别和OA共同作用于细胞24 h,采用CCK-8试剂盒测定细胞存活率,油红O染色观察细胞内脂滴蓄积情况,并采用试剂盒测定细胞内总胆固醇(TC)、甘油三酯(TG)含量。结果 EFPA为成分均一的多糖组分,分子量为125.8 kDa,由甘露糖、葡萄糖、半乳糖、葡萄糖醛酸和阿拉伯糖组成,摩尔比为1.7∶7.4∶1.4∶1.8∶1.0,葡萄糖占比最大,EFPA-R由甘露糖、葡萄糖、半乳糖和阿拉伯糖组成,摩尔比为0.8∶10.6∶2.1∶1.0;在10-300 μg·mL-1范围内,EFPA和EFPA-R对HepG2细胞的抑制作用较弱,作为给药浓度;与空白组相比,模型组细胞中TC、TG含量显著升高(P < 0.01),细胞内红色脂滴显著增多,与模型组相比,EFPA可显著降低细胞中TC、TG含量(P < 0.01),明显减少细胞内红色脂滴(P < 0.05或P < 0.01),EFPA-R干预后细胞则无明显变化。结论 EFPA可明显改善HepG2细胞脂质堆积情况,且呈现剂量依赖性,而半乳糖醛酸(GalA)的存在可能是其抑制HepG2细胞脂质蓄积的关键因素。  相似文献   
2.
多囊卵巢综合征(polycystic ovary syndrome,PCOS)是一种内分泌代谢紊乱综合征,临床表现高度异质性。肥胖是PCOS异质性临床表现之一,超过50%的PCOS患者超重或肥胖。肥胖型PCOS主要表现为高雄激素血症、中心型肥胖和糖脂代谢紊乱,非肥胖型PCOS主要表现为黄体生成激素(luteinizing hormone,LH)水平异常升高。尽管肥胖型和非肥胖型PCOS均存在内分泌代谢异常,然而肥胖可加重PCOS糖脂代谢紊乱;肥胖型PCOS还表现脂肪代谢的异常。综述肥胖型PCOS患者的临床特征、性激素水平、糖脂代谢特征,旨在为肥胖型和非肥胖型PCOS患者新的分型诊治提供参考。  相似文献   
3.
Lipid nanoparticles (LNPs) are becoming popular as a means of delivering therapeutics, including those based on nucleic acids and mRNA. The mRNA-based coronavirus disease 2019 vaccines are perfect examples to highlight the role played by drug delivery systems in advancing human health. The fundamentals of LNPs for the delivery of nucleic acid- and mRNA-based therapeutics, are well established. Thus, future research on LNPs will focus on addressing the following: expanding the scope of drug delivery to different constituents of the human body, expanding the number of diseases that can be targeted, and studying the change in the pharmacokinetics of LNPs under physiological and pathological conditions. This review article provides an overview of recent advances aimed at expanding the application of LNPs, focusing on the pharmacokinetics and advantages of LNPs. In addition, analytical techniques, library construction and screening, rational design, active targeting, and applicability to gene editing therapy have also been discussed.  相似文献   
4.
5.
PurposeTo determine if cone-beam CT and digital subtraction angiography analysis of pelvic arterial anatomy has predictive value for radiation exposure and technical success of prostatic artery embolization (PAE).Materials and MethodsThis prospective, nonrandomized, single-center study included 104 consecutive patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia. Cone-beam CT was performed in 160/208 (76.9%) hemipelves to determine prostatic artery (PA) origin. Classification of pelvic arterial tortuosity was possible in 73/104 (70.2%) patients. Learning curves of 2 interventionalists who performed 86.5% of PAEs were analyzed.ResultsTortuosity of pelvic arteries was classified as mild in 25 (34.2%) patients median age 64 years, moderate in 40 (54.8%) patients median age 69 years, and severe in 8 (11.0%) patients median age 70 years (mild vs moderate, P = .002; mild vs severe, P = .019); median fluoroscopy times were 24, 36, and 46 minutes (P = .008, P = .023); median contrast volumes were 105, 122.5, and 142 mL (P = .029, P = .064); and bilateral PAE rates were 84.0%, 77.5%, and 62.5% (P = .437), respectively. PA origin from superior vesical artery was most frequent (27.5%) and showed higher dose area product (median 402.4 vs 218 Gy ∙ cm2, P = .033) and fluoroscopy time (median 42.5 vs 27 min, P = .01) compared with PA origin from obturator artery, which was least frequent. Interventionalist experience revealed significant impact on procedure times (median 159 vs 130 min, P = .006).ConclusionsTortuosity of pelvic arteries was more frequent in older patients and predicted worse technical outcomes of PAE. PA origin from obturator artery was associated with lower dose area product and fluoroscopy time, especially compared with PA origin from superior vesical artery. Interventionalist experience showed significant influence on technical outcome.  相似文献   
6.
A growing body of data suggests that therapies based on Toll-like receptors (TLR) targeting, in particular TLR4, holds promise in curing autoimmune and inflammatory pathologies still lacking specific treatment, included several rare diseases. While TLR4 activators (agonists) have already found successful clinical application as vaccine adjuvants, the use of TLR4 blockers (antagonists) as antisepsis agents or as agents against inflammatory diseases (including arthritis, multiple sclerosis, neuroinflammations) and cancer is still at a preclinical phase of development. This minireview focuses on recent achievements on the development of TLR4 modulators based on lipid A structure simplification, in particular on compounds having disaccharide or monosaccharide structures. As the TLR4 activity of natural TLR4 ligands (lipopolysaccharide, LPS and its biologically active part, the lipid A) depends on both the structure of endotoxin aggregates in solution and on single-molecule interaction with MD-2 and CD14 receptors, the rational design of TLR4 modulators should in principle take into account both these factors. In the light of the most recent advances in the field, in this minireview we discuss the structure–activity relationship in simplified lipid A analogs, with cationic or anionic amphiphilic structures.  相似文献   
7.
ObjectiveThe beneficial effects of carnitine supplementation on nonalcoholic fatty liver disease are unclear. We conducted a systematic review and meta-analysis to evaluate the effects of carnitine supplementation on liver function, lipid profile, body mass index, body weight, and homeostasis model assessment of insulin resistance in patients with nonalcoholic fatty liver disease.MethodsA comprehensive search of PubMed, Web of Science, Scopus, Cochrane Library, and Google Scholar databases were performed. Only randomized placebo-controlled human studies that examined the effects of carnitine supplementation on liver function, lipid profile, body mass index, body weight, and homeostasis model assessment of insulin resistance up to September 2019 were included. Fixed effects or random-effects models were applied to compute the pooled effect size. Heterogeneity assessments were performed using Cochran’s Q test and I-squared statistics. The quality of the studies was assessed using the Jaded scale.ResultsA total of 5 articles were selected, including 334 individuals (167 in control and 167 in intervention groups). The results demonstrated that carnitine supplementation significantly reduced homeostasis model assessment of insulin resistance (HOMA-IR) (WMD: −0.91; 95 % CI: −1.11, −0.72; p < 0.001, I2 = 0.0 %) and the levels of aspartate aminotransferase (AST) (WMD: −16.62; 95 % CI: −28.11, −5.14; IU/l; p = 0.005, I2 = 93.5 %), alanine aminotransferase (ALT) (WMD: -33.39; 95 % CI: −45.13, −21.66; IU/l; p < 0.001, I2 = 93.4 %), and triglycerides (TG) (WMD: −22.13; 95 % CI: −38.91, −5.34; mg/dl; p = 0.01; I2 = 0.0 %). However, the results of the pooled effect size did not show any significant effect of carnitine supplementation on body mass index (BMI) (WMD: 0.07; 95 % CI: −0.15, 0.29; p = 0.55; I2 = 0.0 %), body weight (WMD: −0.28; 95 % CI: −2.23, 1.68; p = 0.78; I2 = 45.7 %), the levels of gamma-glutamyl transferase (γGT) (WMD: −11.31; 95 % CI: −24.35, 1.73; IU/l; p = 0.09, I2 = 61.1 %), cholesterol (WMD: −13.58; 95 % CI: −46.77, 19.60; mg/dl; p = 0.42; I2 = 94.9 %), high-density lipoprotein-cholesterol (HDL-C) (WMD: 1.36; 95 % CI: −0.96, 3.68; mg/dl; p = 0.25; I2 = 64.7 %), and low density lipoprotein-cholesterol (LDL-C) (WMD: −14.85; 95 % CI: −45.43, 15.73; mg/dl; p = 0.34; I2 = 96.4 %).ConclusionsThis analysis shows that carnitine supplementation for patients with nonalcoholic fatty liver disease demonstrates a reduction in AST, ALT, TG levels and HOMA-IR. However, no significant effect of carnitine supplementation was observed on BMI, body weight, the levels of γGT, TC, HDL-cholesterol and LDL-cholesterol.  相似文献   
8.
目的 针对中医药大数据平台传统的加密方案效率不高的问题,提出一种高效的基于属性的内积加密的数据脱敏算法。方法 Hash(哈希)算法是应用广泛的高效的数据加密方法,但传统的哈希算法基于单一的控制策略,效率不高。本文提出一种基于属性的内积加密的数据脱敏算法,把批量的敏感数据分割为不同长度数据颗粒度,与特定密文的哈希进行内积处理。结果 在面对中医药大数据平台的海量数据加密的场景,与传统的哈希加密算法相比,本文提供的加密算法具有很好的性能。结论 为了保障个人隐私数据不被泄露,中医药大数据平台中的个人医疗数据需要加密脱敏后,才能进行分析处理或对外发布。本文提出的算法具备灵活的数据颗粒度、策略和高效的性能表现,适用于海量的中医药数据脱敏。  相似文献   
9.
目的:探究金水宝片联合依诺肝素对维持性血液透析患者血脂代谢的影响。方法:选取2018年12月至2019年3月马鞍山十七冶医院血液净化中心进行透析的患者154例作为研究对象,根据用药不同分为对照组和观察组,每组77例。对照组常规应用依诺肝素抗凝,观察组在对照组抗凝基础上加用金水宝片,各组均干预3个月,比较2组患者血脂变化及持续血液透析并发症发生情况。结果:治疗后,观察组患者三酰甘油、总胆固醇及低密度脂蛋白胆固醇水平下降,高密度脂蛋白胆固醇升高,与治疗前比较差异均有统计学意义(P<0.05),与对照组治疗后比较,差异有统计学意义(P<0.05);观察组总并发症发生率明显低于对照组,2组比较差异有统计学意义(P<0.05);2组患者维持性血液透析不良反应发生率均较低,组间比较差异无统计学意义(P>0.05)。结论:金水宝片联合依诺肝素有助于改善维持性血液透析患者血脂代谢水平,降低维持性血液透析相关并发症,值得临床推广应用。  相似文献   
10.
了解小颗粒致密低密度脂蛋白中抗氧化维生素含量、氧化特性 ,探讨其对血管内皮细胞脂质过氧化的影响。采用二次密度梯度超速离心的方法分离制备小颗粒致密低密度脂蛋白 ,高压液相色谱测定其抗氧化物质维生素A、E和 β 胡萝卜素 ;连续监测小颗粒致密低密度脂蛋白在 2 34nm的吸光度以测定其氧化敏感曲线 ;在血管内皮培养液中分别加入不同浓度的小颗粒致密低密度脂蛋白 ,培养后测定培养液丙二醛的浓度。实验成功分离小颗粒致密低密度脂蛋白 ,与大而轻低密度脂蛋白相比 ,维生素A、E和 β 胡萝卜素等抗氧化物质及总抗氧化能力明显减少 ,只有大而轻低密度脂蛋白的 6 5 %、39%和 2 4 % ,故小颗粒致密低密度脂蛋白氧化的延迟时间只有大而轻低密度脂蛋白的 37.5 % ,但硫代巴比妥酸反应物质值及氧化速率分别是大而轻低密度脂蛋白的 1 .7倍和 1 .2 8倍 ;培养液中丙二醛含量随加入脂蛋白的浓度和作用时间而增高 ,2 4h时小颗粒致密低密度脂蛋白 5 0mg组、1 0 0mg组、1 5 0mg组与相同剂量大而轻低密度脂蛋白组比较丙二醛显著增高 (P <0 .0 5 )。上述结果提示 :小颗粒致密低密度脂蛋白中抗氧化物质及抗氧化能力下降 ,氧化敏感性增高 ,并促进内皮细胞过氧化损伤  相似文献   
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