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31.
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   
32.
目的观察丙泊酚麻醉对老龄大鼠认知功能及海马神经元γ-氨基丁酸A(GABA)受体表达的影响。方法50只SD老年大鼠随机分为丙泊酚组和对照组,每组25只。丙泊酚组大鼠腹腔注射1%丙泊酚中/长链脂肪乳注射液6 mL/kg,对照组腹腔注射等体积的生理盐水。麻醉后1 d进行Morris水迷宫实验,分别采用HE染色和尼氏体染色观察海马区神经细胞及尼氏体(Nissl体)形态学变化,Western Blot检测GABA蛋白量表达。结果麻醉后,2组大鼠肛温、心率、呼吸频率、血氧饱和度比较,差异均无统计学意义(P>0.05)。随着实验时间的延长,2组大鼠逃逸潜伏期、总里程数逐渐减小,丙泊酚组大鼠各时间点逃逸潜伏期、总里程均高于对照组,差异有统计学意义(P<0.05)。丙泊酚组大鼠穿越平台区域次数、时间小于、短于对照组,差异有统计学意义(P<0.05)。对照组海马区Nissl体存在于细胞浆及树突,染色较深,神经细胞排列整齐,形态规则;丙泊酚组Nissl体消失,神经细胞数量减少,细胞核破裂、丢失。丙泊酚组大鼠海马GABA蛋白表达量低于对照组,差异有统计学意义(P<0.05)。结论丙泊酚对大鼠认知功能有影响,并与海马区GABA的表达相关。  相似文献   
33.
Platelet function has been described by many laboratory assays, and PL-11 is a new point-of-care platelet function analyzer based on platelet count drop method, which counts platelet before and after the addition of agonists in the citrated whole blood samples. The present study sought to compare PL-11 with other three major more established assays, light transmission aggregometry (LTA), VerifyNow? aspirin system and thromboelastography (TEG), for monitoring the short-term aspirin responses in healthy individuals. Ten healthy young men took 100?mg/d aspirin for 3-day treatment. Platelet function was measured via PL-11, LTA, VerifyNow and TEG, respectively. The blood samples were collected at baseline, 2 hour, 1 day during the aspirin treatment and 1 day, 5?±?1 days, 8?±?1 days after the aspirin withdrawal. Moreover, 90 additional healthy subjects were recruited to establish a reference range for PL-11. Platelet function of healthy subjects decreased significantly 2 hours after 100?mg/d aspirin intake and began to recover during 4–6 days after the aspirin withdrawal. Correlations between methods were PL-11 vs. LTA (r?=?0.614, p?<?0.01); PL-11 vs. VerifyNow (r?=?0.829, p?<?0.01); PL-11 vs. TEG (r?=?0.697, p?<?0.001). There was no significant bias between PL-11 and LTA at baseline (bias?=?1.94%, p?=?0.804) using Bland-Altman analysis, while the data of PL-11 were significantly higher than LTA (bias?=?24.02%, p?<?0.001) during the aspirin therapy. The reference range for PL-11 in healthy young individuals was from 66.8 to 90.5% (95%CI). When aspirin low-responsiveness was defined as LTA?>?20%, the cut-off values for each method were, respectively: PL-11?>?50%, VerifyNow?>?533 ARU, TEG?>?60.2%. The results of different platelet function assays were uninterchangeable for monitoring aspirin response and correlations among them were also varied. Correlations among PL-11 and other three major assays suggested the ability of PL-11 to assess the treatment effects of aspirin. But a large cohort study is needed to confirm the cut-off value of aspirin response detected by PL-11.  相似文献   
34.
目的 观察单次9 h高压氧(hyp erbaric oxygen,HBO)治疗对局灶性脑梗死大鼠凋亡诱导因子 (apoptosis-inducing factor,AIF)、线粒体膜电位(mitochondrial membrane potential,MMPo)的影响,探讨 HBO治疗的神经保护作用。 方法 108只SD大鼠制作永久性大脑中动脉闭塞模型,随机分为对照组和HBO组,每组各54只。造 模成功3 h后,HBO组实行HBO干预,压力0.2 MPa持续9 h,对照组呼吸常压空气。采用Garcia评分评估 大鼠神经功能,比较两组造模后13 h、24 h和72 h神经功能改善情况,并在各时间点检测大鼠缺血半 暗带脑组织凋亡细胞数、线粒体和细胞核AIF表达及MMPo水平。 结果 ①神经功能评分:HBO组13 h(P <0.001)、24 h(P =0.04)神经功能评分改善比对照组更明显。 ②凋亡细胞数:HBO组13 h、24 h凋亡细胞数较对照组更少(均P <0.001)。③AIF在线粒体和细胞核的 表达:13 h、24 h、72 h各时间点HBO组AI F在线粒体的表达均较对照组多(均P <0.001);各时间点HBO 组AIF在细胞核的表达均较对照组少(均P <0.001)。④MMPo:各时间点HBO组MMPo均高于对照组(均 P <0.001)。 结论 HBO治疗可改善大鼠神经功能,稳定MMPo,抑制AIF由线粒体向细胞核转移可能是其神经保 护作用的机制之一。  相似文献   
35.
刘杰  李葱  高英 《现代肿瘤医学》2019,(14):2601-2604
炎性肌纤维母细胞瘤(inflammatory myofibroblastic tumor,IMT)作为一种低度恶性潜能的间叶组织来源的肿瘤,病因及发病机制不明。主要见于儿童和青少年,最常见的部位是肺、肠系膜、网膜,发生于乳腺的比较罕见,且往往单发。乳腺炎性肌纤维母细胞瘤的临床症状及影像学特点均不典型,术前易造成误诊,本文复习国内外文献报道的乳腺炎性肌纤维母细胞瘤,从发病机制、临床表现、影像学特征、病理学特征、鉴别诊断、治疗及预后等方面作一系统综述。  相似文献   
36.
刘洁  王斐  杨侠  胡爱丽 《陕西中医》2020,(3):318-320,349
目的:观察黄连解毒汤对重度颅脑损伤合并肺部感染患者血气指标和炎症因子的影响,探讨其治疗效果。方法:随机抽签方式将77例重度颅脑损伤合并肺部感染患者分为两组。对照组35例接受常规治疗,研究组42例在常规治疗基础上,联合黄连解毒汤直肠灌注及全身擦浴治疗。评估两组临床效果,记录两组呼吸机使用时间、ICU入住时间及治疗费用,测定两组治疗前后血气指标和炎症因子。结果:两组临床治疗效果间差异无统计学意义(P>0.05)。与对照组比,研究组呼吸机使用时间和ICU入住时间明显缩短,ICU治疗费用显著减少(P<0.01)。治疗后两组SaO、PaO2水平明显上升,PaCO2及血清PCT、IL-1β、HMGB-1、CRP水平明显下降(P<0.05)。组间比较,研究组SaO、PaO2水平高于对照组,PaCO2及血清PCT、IL-1β、HMGB-1、CRP水平低于对照组(P<0.05)。结论:黄连解毒汤直肠灌注联合全身擦浴可明显控制重度颅脑损伤合并肺部感染患者感染病症,改善血气指标,调节炎症反应,缩短呼吸机使用时间和ICU入住时间,减少患者的治疗费用。  相似文献   
37.
This study aimed to compare the differences in characteristics and prognoses between Asian and white patients receiving immunotherapy for nonsmall cell lung cancer (NSCLC). We studied 390 patients who received atezolizumab as part of the POPLAR or OAK trial, and analyzed the differences in baseline characteristics, outcomes and genetic mutations in blood samples between Asian and white patients. Overall survival (OS) was longer in Asian compared to white patients (median OS: 18.7 vs. 11.1 months; p = 0.005). Race was identified as an independent prognostic factor for OS (Asian vs. white: hazard ratio 0.647, 95% confidence interval 0.447–0.936, p = 0.021), together with performance status, histology, baseline sum of the longest tumor diameters (BLSLD) and number of metastatic sites. The two groups also differed in terms of characteristics including smoking history, BLSLD, epidermal growth factor receptor (EGFR) mutation frequency, programmed death-ligand 1 expression and blood-based tumor-mutation burden. Blood mutations of STK11, EGFR, KEAP1, POLE, GRM3, ATM and STAG2 were associated with treatment response, and TP53, KEAP1, APC, RB1, CREBBP, EPHA5 and STAG2 mutations were associated with OS. The blood-based mutation profiles differentiated between Asian and white patients, especially in relation to EGFR (23.8 vs. 8.5%), TP53 (30.2 vs. 46.9%) and STK11 (1.6 vs. 12.3%) mutations (all p < 0.05). The different clinicopathological features and mutation profiles in Asian and white patients may explain the superior outcome following atezolizumab treatment in Asian patients with NSCLC. The results of this study have important implications for further studies on racial disparities in relation to immunotherapy.  相似文献   
38.
皮肤鳞状细胞癌是具有发病率高、发展快、可转移、易误诊等特点的一种恶性肿瘤,对人类的健康造成威胁。随着中医的发展和现代医学实验研究技术的进步,中医药在皮肤鳞状细胞癌的现代研究方面也取得一定成果。目前临床上治疗鳞状细胞癌多采取手术及药物化疗等,因不良反应的存在,患者接受度低。中药具有多靶点、安全性高、不良反应少等优势,在治疗皮肤鳞状细胞癌中中医具有一定优势,本文将围绕中药单体、中药复方,以及针灸在治疗皮肤鳞状细胞癌的研究进展展开论述和思考。  相似文献   
39.
40.
侯万举  曹洁  王娟 《天津医药》2019,47(2):155-158
目的 研究血清窖蛋白-1 (Cav-1) 在慢性阻塞性肺疾病 (COPD) 相关肺动脉高压 (PAH) 患者中的表达及其意义。方法 选取稳定期COPD患者65例, 根据是否合并PAH分成COPD组 [肺动脉收缩压 (PASP) <40 mmHg, 35例] 及COPD-PAH组 (PASP ≥40 mmHg, 30例)。另选取在本院健康体检的志愿者30例作为对照组。对比各组基线资料、 动脉血气分析、 肺功能指标, 以及血清Cav-1、 白细胞介素 (IL) -6和肿瘤坏死因子-α (TNF-α) 的表达水平。绘制受试者工作特征 (ROC) 曲线, 评价Cav-1对COPD合并PAH的诊断价值。结果 COPD-PAH组与COPD组第一秒用力呼吸容积 (FEV1) /用力肺活量 (FVC)、 FEV1占预计值百分比 (FEV1%) 及氧分压 [p (O2 )] 低于对照组, 而二氧化碳分压 [p (CO2 )]、 PASP均高于对照组 (P<0.01)。COPD-PAH组p (O2 ) 低于COPD组, p (CO2 )、 PASP均高于COPD 组 (P<0.01)。对照组、 COPD组及COPD-PAH组Cav-1表达水平呈逐渐降低趋势, 而IL-6、 TNF-α表达水平呈逐渐升高趋势 (P<0.01)。血清Cav-1诊断COPD合并PAH的ROC曲线下面积为0.902 (0.821~0.955), 最佳截断值为 6.66 μg/L, 此时诊断敏感度为76.7%, 特异度为85.7%, 与多普勒超声诊断仪测量PASP结果比较一致性较好 (Kappa 值=0.627)。结论 血清Cav-1在COPD相关PAH患者表达明显下调, 可以作为预测COPD相关PAH的新型血清标志物。  相似文献   
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