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Shouwen Zhang  Jie Wang 《Drug delivery》2016,23(9):3696-3703
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   
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目的探讨前列地尔联合长春西汀治疗急性脑梗死的疗效。方法选取2015年3-12月在我科接受治疗的90例急性脑梗死患者,随机分为治疗组(45例)和对照组(45例)。两组患者均给予抗血小板、降血脂等常规对症治疗,11 d为1个疗程。对照组给予长春西汀静脉输液治疗,治疗组在对照组基础上加以前列地尔治疗。比较两组临床治疗效果,治疗前后神经功能恢复情况、日常生活能力恢复情况、并发症发生率及安全性。结果治疗组总有效率为93.3%,对照组为71.1%,治疗组明显高于对照组,差异有统计学意义(P<0.05)。两组患者用药11 d后,神经功能缺损评分均高于治疗前,且治疗组明显高于对照组,差异均有统计学意义(P<0.05)。治疗组患者用药11d及90 d后日常生活能力恢复情况优于对照组,差异有统计学意义(P<0.05)。两组均无严重药物不良反应。结论前列地尔联合长春西汀治疗急性脑梗死疗效显著,值得临床推广应用。  相似文献   
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BackgroundCoronary artery bypass grafting (CABG) improves survival in patients with heart failure and severely reduced left ventricular systolic function (LVEF). Limited data exist regarding adverse cardiovascular event rates after CABG in patients with heart failure with midrange ejection fraction (HFmrEF; LVEF > 40% and < 55%).MethodsWe analyzed data on isolated CABG patients from the Veterans Affairs national database (2010-2019). We stratified patients into control (normal LVEF and no heart failure), HFmrEF, and heart failure with reduced LVEF (HFrEF) groups. We compared all-cause mortality and heart failure hospitalization rates between groups with a Cox model and recurrent events analysis, respectively.ResultsIn 6533 veterans, HFmrEF and HFrEF was present in 1715 (26.3%) and 566 (8.6%) respectively; the control group had 4252 (65.1%) patients. HFrEF patients were more likely to have diabetes mellitus (59%), insulin therapy (36%), and previous myocardial infarction (31%). Anemia was more prevalent in patients with HFrEF (49%) as was a lower serum albumin (mean, 3.6 mg/dL). Compared with the control group, a higher risk of death was observed in the HFmrEF (hazard ratio [HR], 1.3 [1.2-1.5)] and HFrEF (HR, 1.5 [1.2-1.7]) groups. HFmrEF patients had the higher risk of myocardial infarction (subdistribution HR, 1.2 [1-1.6]; P = .04). Risk of heart failure hospitalization was higher in patients with HFmrEF (HR, 4.1 [3.5-4.7]) and patients with HFrEF (HR, 7.2 [6.2-8.5]).ConclusionsHeart failure with midrange ejection fraction negatively affects survival after CABG. These patients also experience higher rates myocardial infarction and heart failure hospitalization.  相似文献   
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目的探讨经皮冠状动脉介入(PCI)和静脉溶栓在急性心肌梗死患者中的应用价值。方法选择我院2013年1月至2014年9月收治的60例急性心肌梗死患者作为研究对象,随机分为实验组和对照组各30例。实验组患者采用PCI治疗,对照组患者采用静脉溶栓治疗,比较两组患者血管再通率、死亡发生率、ST段回落情况、住院时间、近远期不良事件发生率、左室舒张末径和左室射血分数变化情况。结果实验组血管再通率显著高于对照组,差异有统计学意义(P<0.05),而近期和远期不良事件发生率均低于对照组,近期不良事件发生率组间比较差异有统计学意义(P<0.05),而远期不良事件发生率比较差异无统计学意义(P>0.05)。实验组患者死亡发生率、ST段回落和住院时间均低于对照组,差异均有统计学意义(P<0.05)。实验组左室射血分数在术后1个月、3个月和6个月时均显著高于对照组,差异均有统计学意义(P<0.05)。结论急性心肌梗死患者应用PCI治疗可显著提高血管再通率、降低死亡和不良事件发生率,有效改善心功能。  相似文献   
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李宁  徐琴  黄勇华 《河北医药》2016,(16):2405-2408
目的:观察脑心通胶囊(步长制药)治疗脑梗死合并心肌缺血患者的临床疗效。方法选取2013年10月至2014年12月北京21所医院神经内科收治的符合入组条件的急性脑梗死伴心肌缺血患者,非随机分为脑心通组(基础治疗基础上加用步长脑心通胶囊)和对照组(仅基础治疗)。对比分析第4周、8周、12周时2组心电图变化以及使用NIHSS和改良mRankin评估第12周时神经功能变化。结果入组544例,剔除16例(不良事件2例、自动放弃1例、违背规则1例、失访6例、其他6例),实际完成试验528例(包含测量资料缺失病例),其中脑心通组291例,对照组237例。心肌缺血改善的有效率脑心通组和对照组第4周差异无统计学意义(18.1%、14.9%, P =0.704);但第8周(27.7%、14.3%, P =0.001)和第12周(31.3%、16.9%,P <0.01)差异有统计学意义( P <0.05)。第12周时NIHSS减少≥2分脑心通组(77.7%)明显高于对照组(68.4%)( P <0.05),mRankin 减少≥1分脑心通组(67.7%)显著高于对照组(56.1%)( P <0.05)。多因素分析心电图改善的独立影响因素是脑心通( P =0.005)和第12周时AST的降低( P =00.47);神经功能改善的影响因素包括脑心通治疗、基线收缩压和肌酐水平、既往心脏病或高脂血症病史。结论脑心通胶囊联合基础治疗对脑梗死合并心肌缺血临床疗效确切。  相似文献   
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Objective: This study investigated the effect of regular swimming exercise according to the duration-intensity on neurocognitive function in a cerebral infarction rat model.

Methods: Forty male Sprague–Dawley 10-week-old rats, weighing 300 ± 50 g, were subjected to photothrombotic cerebral infarction. The remaining 36 rats were randomly divided into four groups (n = 9 per group: non-exercise (group A); swimming exercise of short duration-intensity (5 min/day, group B); swimming exercise of moderate duration-intensity (10 min/day, group C); and swimming exercise of long duration-intensity (20 min/day, group D). Exercise was performed five times a week for 4 weeks, beginning the day after cerebral infarction. Neurocognitive function was evaluated with the Morris water maze test. Immunohistochemistry and western blot analysis examined brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) at 4 weeks postinfarction.

Results: At 4 weeks postinfarction, escape latency was found to be shorter in group C than in any of groups A, B, or D. Immunohistochemistry revealed the most significant immunoreactivity for BDNF and VEGF in group C. Western blot analysis demonstrated that BDNF and VEGF proteins were markedly expressed in group C.

Conclusions: Regular swimming exercise of moderate duration-intensity may be the most effective exercise protocol for the recovery of neurocognitive function in cerebral infarction rat model.  相似文献   

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