香叶木苷凝胶剂的制备及体外释药特性研究

目的:筛选香叶木苷凝胶剂的最优处方,并考察其体外释药特性。方法:以卡波姆940为基质制备香叶木苷凝胶剂;以累积释放率为考察指标,卡波姆940、乙醇、丙三酮用量以及pH值为考察因素设计L9(34)正交试验,优化香叶木苷凝胶剂的处方并验证。以香叶木苷软膏剂为参照,采用透析袋扩散法考察按最优工艺所制香叶木苷凝胶剂的体外释药特性。结果:香叶木苷凝胶剂最优处方为卡波姆940 1.5 g、乙醇15 m L、丙三醇8 g、pH 6。按最优处方所制凝胶剂呈黏稠状棕黄色半固体,涂展性良好;释药2 h时的平均累积释放率为(12.67±0.12)%。体外释药试验结果显示,香叶木苷凝胶剂在12 h内释放较快,然后逐渐放缓,12、24 h时的累积释放率分别为(71.93±0.42)%、(80.47±0.54)%,其释药符合Higuchi方程;香叶木苷软膏剂释放较慢,12、24 h时的累积释放率分别为(41.74±0.18)%、(62.63±0.59)%,其释药符合一级方程。结论:成功优化了香叶木苷凝胶剂的处方;所得香叶木苷凝胶剂释药性良好。     

原料药粒径对盐酸普萘洛尔渗透泵片释药行为的影响

目的:研究原料药粒径等对盐酸普萘洛尔渗透泵片释药行为的影响。方法:取不同批号盐酸普萘洛尔及同批号重结晶前、后的原料药均按相同处方制备成渗透泵片,考察药物体外释放情况及释药24h后衣膜形态;并对上述不同原料药的粒径分别以光学显微镜和激光粒度分析仪进行证实。结果:以原料药粒径较小的渗透泵片释放完毕后衣膜变形,且不能维持零级释放,原料药粒径较大的渗透泵片结果与之相反。不同原料药经仪器证实粒径确有差异。结论:原料药的粒径可影响制备的渗透泵片的释放行为,提示性状稳定的原料药的合理选择在制剂过程中不可忽视。     

染料木素MePEG-PLGA共聚物胶束体内外抗肿瘤作用

目的 探讨染料木素MePEG-PLGA共聚物胶束对人肝癌SMMC-7721细胞的体内外抗肿瘤作用。方法 采用MTT法、Annexin V-FITC/PI染法分别考察染料木素MePEG-PLGA共聚物胶束对人肝癌SMMC-7721细胞的细胞毒性、细胞凋亡、细胞周期的影响;通过荷肝SMMC-7721瘤裸鼠体内抗肿瘤试验,考察染料木素胶束的体内抗肿瘤效应。结果 染料木素胶束对肝癌SMMC-7721细胞的抑制率均高于染料木素,最高抑制率分别可达83.26%,78.25%。流式细胞仪检测结果显示,染料木素胶束组能够提高染料木素对SMMC-7721细胞凋亡的诱导能力,并且呈浓度依赖性。5,10,20 μg·mL^-1的染料木素组和染料木素胶束组药物作用于SMMC-7721细胞48 h时,染料木素胶束能够明显提高染料木素对细胞G₂/M期细胞的阻滞作用,并且呈现浓度依赖性。体内抗肿瘤试验结果表明,相同浓度的染料木素胶束组的抑瘤效果显著强于染料木素乳剂组,呈浓度依赖性,最高抑瘤率可达55.41%。结论 染料木素MePEG-PLGA共聚物胶束在体内和体外均有显著的抗肝癌作用。     

盐酸美金刚缓释微丸的制备及体外释放度考察

目的:制备盐酸美金刚缓释微丸,并对其体外释放度进行考察。方法:采用流化床包衣法制备盐酸美金刚载药微丸,再用Eudragit RL 30D和Eudragit RS 30D进行包衣,制成盐酸美金刚缓释微丸,并考察盐酸美金刚缓释微丸的体外释药行为。结果:体外释放度试验显示,制备的盐酸美金刚缓释微丸在24 h内平稳释放且释药完全,释药规律符合零级释药模型。结论:用本方法制备的盐酸美金刚缓释微丸具有缓释效果。     

薏苡仁油纳米粒的体外释药特性

目的:考察比较薏苡仁油纳米粒与薏苡仁油原料的体外释药特性。方法:以薏苡仁油主成分甘油三油酸酯为指标性成分,采用超高效液相色谱-质谱联用(UPLC-MS)技术,建立薏苡仁油纳米粒体外释放量的测定方法;分别考察比较薏苡仁油纳米粒及薏苡仁原料在不同释放介质的释药行为,并运用多种数学模型对释药实验结果进行分析。结果:薏苡仁油纳米粒中的药效成分初期有一快速释放,2 h释放度超过30%,随后药效成分持续缓慢释放,至72 h药物释放度达90%;其释放过程以Weibull分布模型拟合最佳,相关系数r大于0.98;薏苡仁油原料48 h释放度达90%以上。结论:与薏苡仁油原料相比,薏苡仁油纳米粒口服给药系统能使药效成分达到缓释作用,且其释药行为符合Weibull分布模型。     

盐酸普萘洛尔延时脉冲微丸的制备与体外释放研究

目的:基于有机酸诱导原理制备盐酸普萘洛尔延时脉冲微丸,并研究其体外释药行为。方法:以低渗型丙烯酸树脂为包衣材料,采用空白丸心上药法制备含有机酸的载药微丸,考察处方因素对药物释放的影响,应用Box-Behnken效应面设计优化处方。通过有机酸与包衣膜相互作用试验探索其体外释药机制。结果:药物与琥珀酸分层的微丸具有较理想的脉冲释药特征,最优处方体外释药时滞约为4h,时滞后2h累积释放量90%以上,其体外释放曲线符合logistic模型。有机酸能够降低衣膜的玻璃化转变温度并促进其水化,从而提高包衣膜渗透性而加速释放。结论:所得微丸具有良好的体外脉冲释放效果。     

毛兰素TPGS/F68混合胶束的制备及质量评价

目的 制备毛兰素混合胶束,评价该胶束的质量,并考察其体外释药特性.方法 采用薄膜分散法,以聚乙二醇1000维生素E琥珀酸酯、泊洛沙姆188为载体,制备毛兰素混合胶束.采用正交试验,以包封率为指标优化制备工艺;以临界胶束浓度、粒径等作指标对混合胶束的表征;考察混合胶束的体外释药特性.结果 毛兰素混合胶束的最佳处方为:毛兰...     

双氯酚酸钾双层片体外释放及其影响因素

目的 :考察双氯酚酸钾双层片的体外释放特征及其影响因素。方法 :采用紫外分光光度法 ,按照《中国药典》的转篮法测定体外释放度。采用Higuchi方程模拟体外释药行为 ,对主要释药参数进行统计学分析。结果 :双层片溶出参数T0 3=0 10h ,Td=3 30h ,T0 9=9 19h。压力对体外释放度速率无显著性影响 ;不同转速对双层片的早期释药行为有显著性影响 ,对中、后期释药行为无显著性影响 ;溶出介质的 pH对体外释放度有极显著性影响。结论 :双层片在体外具有良好的缓释和速释特征 ,适宜的溶出介质是体外释放度试验的关键 ,其最终确定有赖于体内试验     

布地奈德结肠定位片的体外释放度实验方法及其释药机制研究

建立3步释放度实验法考察布地奈德结肠定位片的体外释药行为，并通过模型拟合阐明其释药机制。分别模拟胃、小肠和结肠部位的pH值、肠道菌群、特异性生物酶、蠕动和转运时间等生理参数，设计定位片体外释放度试验，24 h内定时取样，HPLC法测定布地奈德的累积释放度，采用多种数学模型对定位片的释药曲线进行拟合度分析。结果表明，布地奈德结肠定位片在2 h内无药物释放，6 h累积释放度约为5%，24 h累积释放度达77.5%，其体外释药行为符合First-order模型。本实验建立的3步释放度实验可作为评价布地奈德结肠定位片结肠靶向性的方法，定位片的释药行为遵从以渗透压作为主要释药动力的微孔型渗透泵的释药机制。     

复方甲硝唑缓释栓的制备及体外释放度考察

目的:制备适合老年人用的复方甲硝唑缓释栓,并考察其体外释放度。方法:以甲硝唑和硝酸咪康唑为主药,羟丙基甲基纤维素为骨架材料,利用热熔法制备缓释栓剂;同时采用篮法,以0.5%十二烷基硫酸钠溶液为介质,硝酸咪康唑为对象,进行体外释放度评价。结果:所制制剂外观、性状良好,可持续12h释药,体外释放行为符合Higuchi方程。结论:该制剂制备工艺合理、简单易行,并具有良好的体外释药特性,符合缓释制剂的要求。     

染料木素MePEG-PLGA共聚物胶束的制备及其药动学研究

目的 制备染料木素(GEN)MePEG-PLGA共聚物胶束,考察其理化性质、初步稳定性及静脉给药后大鼠体内的药动学行为。方法 采用改良的自乳化溶剂挥发法制备胶束,考察其形态、包封率、载药量、粒径和Zeta电位;采用动态膜透析技术考察其释药行为,并对其释药规律进行拟合;将胶束冻干品置于4 ℃冰箱中保存,分别于放置1 d、10 d、1个月、3个月、6个月后取样,考察其包封率和载药量变化;对健康大鼠尾静脉注射GEN胶束,采用HPLC测定GEN在大鼠体内的血药浓度,采用DAS 2.0软件处理血药浓度数据,SPSS 17.0软件对主要药动学参数进行统计学分析。结果 制备所得胶束的包封率为(84.43±2.93)%,载药量为(2.63±0.91)%,粒径为(63.75±4.12)nm;GEN胶束的释药行为最符合Weibull模型;GEN胶束冻干品6个月渗漏率为2.45%,载药量下降0.18%;大鼠尾静脉注射GEN胶束和GEN乳剂40 mg·kg^-1后,主要药动学参数AUC_0-t分别为(99.46±4.77)mg·L^-1·h和(57.51±1.37)mg·L^-1·h,t_1/2分别为(7.48±1.15)h和(4.95±1.15)h,C_max分别为(16.03±1.20)mg·L^-1和(16.73±1.10)mg·L^-1,CL分别为(0.36±0.02)L·h^-1·kg^-1和(0.67±0.02)L·h^-1·kg^-1。结论 制备所得的GEN胶束形态规整,粒径分布狭窄,包封率较高,具有一定的缓释特征,稳定性良好,并且明显改变了GEN的药动学行为,使其消除减慢,同时提高了药物的生物利用度。     

金雀异黄素对正常的和过氧化氢损伤的内皮细胞的影响(英文)

目的 :观察金雀异黄素 (genistein)对体外培养的血管内皮细胞 (ECV 3 0 4)生长的影响和对过氧化氢引起ECV 3 0 4细胞损伤的保护作用。方法 :将ECV 3 0 4细胞与金雀异黄素 0 .1～ 1 0 0 μmol·L-1共同孵育 2 4～ 96h ,通过MTT法测定细胞存活率。为了观察金雀异黄素对过氧化氢引起ECV 3 0 4细胞损伤的保护作用 ,将细胞分成 3组 ,分别为对照组、过氧化氢损伤模型组和金雀异黄素治疗组 ,治疗组ECV 3 0 4细胞先与金雀异黄素 6.2 5～ 1 0 0 μmol·L-1共同孵育 3 0min ,然后模型组和治疗组ECV3 0 4细胞均加入过氧化氢 1 0mmol·L-1孵育 ,3 0min后以MTT法测定OD值 ,以此反映各组ECV 3 0 4的生存情况。结果 :金雀异黄素对于正常ECV 3 0 4细胞生长的作用与浓度和作用时间有关 ,浓度为1 0 0 μmol·L-1时 ,作用 2 4,48h能明显促进ECV3 0 4生长 (P <0 .0 1 ) ,而作用 96h则表现为明显的抑制作用 (P <0 .0 5 ) ;浓度为 1 0 μmol·L-1时 ,作用48,72h对ECV 3 0 4细胞生长也有促进作用 (P <0 .0 5 ) ;而当金雀异黄素浓度降低为 0 .1 ,1 μmol·L-1时 ,对ECV 3 0 4细胞生长无明显影响。过氧化氢 1 0mmol·L-1可使ECV 3 0 4的存活率明显下降(P <0 .0 5 ) ;预先给予金雀异黄素 2 5 ,5 0 ,1 0 0 μmol·L-1能浓度依赖性地     

一种新型海洋多糖纳米材料的制备及载药特性研究

目的 以天然海洋多糖聚甘露糖醛酸(PM)为原料,制备一种生物相容、生物可降解纳米材料,以难溶性药物他克莫司（FK506）为模型药物制备载药胶束,并对其体外释药特性进行考察。方法 以油胺为疏水端,与PM通过酰胺反应制备纳米材料,利用FT-IR、1H-NMR对其结构进行表征。通过超声乳化法制备FK506胶束,利用原子力显微镜与马尔文激光粒度仪分析载药胶束的形态、粒径及zeta-电位。利用高效液相色谱法测定FK506胶束的载药量和包封率。采用体外透析法分析FK506胶束的体外释放特性。结果 油胺与PM等摩尔比投料反应的枝接率为56.8%,FK506胶束外形为球状且分散均匀,粒径大小在 100~150 nm,zeta-电位为?50 mV,多分散系数＜0.2,载药量和包封率分别为17.6±0.21% 和97.7±1.19%。体外释药分为2个阶段,前12 h释放较快,释放药物的64.5±5.8%,后一阶段药物释放较慢,至48 h时可释放药物89.2±6.9%。结论 成功制备生物可降解的PM纳米材料,以其为载体制得的FK506胶束可以提高FK506的溶解性,在体外具有明显的缓释特征,PM纳米材料具有良好的应用前景。     

Pharmaceutical evaluation of genistein-loaded pluronic micelles for oral delivery

The purpose of the present study was to determine whether Pluronic F127 polymeric micelles could improve the oral bioavailability of a poor water-soluble drug, such as genistein. Genistein is a phytoestrogen that has estrogenic activity. F127 triblock copolymer consists of PEO100-PPO65-PEO100. Genistein was incorporated in the Pluronic F127 polymeric micelles by a solid dispersion method. The genistein release of genistein-loaded polymeric micelles was studied in vitro (in pH 1.2 and pH 6.8). And the oral bioavailabilities of genistein powder and genistein-loaded micelles were estimated at a dose of 4.0 mg/kg as genistein in rats. Drug loading amount and drug loading efficiency were 11.18% and 97.41%, respectively. The average size of the genistein-loaded polymeric micelles was 27.76 nm. And genistein release of the genistein-loaded polymeric micelles in vitro was 58% (pH 1.2) and 82% (pH 6.8). The bioavailability of genistein-loaded polymeric micelles was better than genistein powder. Consequently, Pluronic F127 polymeric micelles are an effective delivery system for the oral administration of genistein.     

异黄酮genistein对小鼠恶性黑色瘤转移的实验性治疗

目的:研究异黄酮genistein 对肿瘤转移的治疗作用。方法:B16-BL6 细胞由尾静脉注入C57BL/6 小鼠体内,于d 15 观察动物肺转移灶。genistein 混悬于2% 卵磷脂中,从接种瘤细胞前1 天开始ip,剂量为100 和200mg·kg^-1·d^-1 。结果:genistein 可抑制肺转移灶形成,200 mg·kg^-1 用药组小鼠转移灶数目明显减少;作为对照,腹腔给予环磷酰胺100 mg·kg^-1 后,形成的转移灶数目无明显变化,但形成的转移瘤灶体积减小。当genistein 和环磷酰胺合用时,转移小鼠的存活时间明显延长。结论:genistein 可抑制肿瘤转移,其作用与细胞毒药物不同, 与细胞毒药物合用可提高其抗肿瘤转移的作用。     

Multiple effects and stimulation of insulin secretion by the tyrosine kinase inhibitor genistein in normal mouse islets.

1. Islets from normal mice were used to test the acute effects of genistein, a potent tyrosine kinase inhibitor, on stimulus-secretion coupling in pancreatic beta-cells. 2. Genistein produced a concentration-dependent (10-100 microM), reversible, increase of insulin release. This effect was marginal on basal release or in the presence of non-metabolized secretagogues, and much larger in the presence of glucose or other nutrients. The increase in insulin release caused by 100 microM genistein was abolished by adrenaline or omission of extracellular Ca2+. It was not accompanied by any rise of cyclic AMP, inositol phosphate or adenine nucleotide levels. 3. Although genistein slightly inhibited ATP-sensitive K+ channels, as shown by 86Rb efflux and patch-clamp experiments, this effect could not explain the action of the drug on insulin release because the latter persisted when ATP-sensitive K+ channels were all blocked by maximally effective concentrations of glucose and tolbutamide. Genistein was also effective when ATP-sensitive K+ channels were opened by diazoxide and the beta-cell membrane depolarized by 30 mM K, but ineffective in the presence of diazoxide and normal extracellular K. 4. Genistein paradoxically decreased Ca2+ influx in beta-cells, as shown by the inhibition of glucose-induced electrical activity, by the inhibition of Ca2+ currents (perforated patches) and by the lowering of cytosolic [Ca2+]i (fura-2 technique). Genistein thus increases insulin release in spite of a lowering of [Ca2+]i in beta-cells. 5. Daidzein, an analogue of genistein reported not to affect tyrosine kinases, was slightly less potent than genistein on K+ and Ca2+ channels, but increased insulin secretion in a similar way.(ABSTRACT TRUNCATED AT 250 WORDS)     

Genistein-induced apoptosis of human breast cancer MCF-7 cells involves calpain-caspase and apoptosis signaling kinase 1-p38 mitogen-activated protein kinase activation cascades

The molecular mechanisms of genistein-induced apoptosis of human breast cancer MCF-7 cells were investigated. Genistein showed 50% cell growth inhibition at IC50=27.5+/-0.8 micromol/l in 24 h incubation under 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay conditions. Genistein is known to express both cell growth activity at nanomolar concentrations and anti-cell growth activity at micromolar concentrations. It was found that genistein at 100 micromol/l concentration effectively induced apoptosis of MCF-7 cells in 24 h. Genistein-induced apoptosis involved activation of calpain, caspase 7 and poly(ADP ribose) polymerase. Dantrolene, an inhibitor of Ca release from the endoplasmic reticulum, inhibited genistein-induced activation of calpain and caspase 7, in addition to effectively negating genistein-induced apoptosis. MCF-7 cells treated with genistein also showed increased phosphorylation of p38 mitogen-activated protein kinase, whereas no effect was observed for extracellular signal-regulating kinase 1/2. Phosphorylation of apoptosis signaling kinase 1, an upstream regulator of p38 mitogen-activated protein kinase, was also increased by genistein treatment. Genistein-induced phosphorylation of apoptosis signaling kinase 1 and p38 mitogen-activated protein kinase was diminished by the presence of dantrolene. These results suggest that genistein-induced apoptosis in MCF-7 cells is mediated through calpain-caspase 7 and apoptosis signaling kinase 1-p38 mitogen-activated protein kinase activation cascades that involve Ca release from the endoplasmic reticulum.     

金雀异黄素对猪血小板聚集和胞浆游离钙的影响

AIM: To study the effects of genistein on aggregation and cytosolic free calcium concentration in platelets. METHODS: Using turbidimetry to analyse aggregation and using Fura-2 fluorescence technique to determine Ca2+ level. RESULTS: Genistein strongly inhibited the pig platelet aggregation induced by thrombin (250 U.L-1). When genistein concentrations were 5 and 20 mumol.L-1, the inhibition rates on the aggregation were 52% and 73%, respectively. Genistein inhibited the rise of cytosolic free calcium concentration in platelets stimulated by thrombin (500 U.L-1) in the presence of extracellular Ca2+ 1 mmol.L-1. When genistein concentrations were 10, 20, 40, and 80 mumol.L-1, the inhibition rates were 24%, 40%, 63%, and 65%, respectively, but no effect on thrombin-induced internal Ca2+ release from dense tubular system. CONCLUSION: Genistein is a potential anti-platelet agent, mainly due to an inhibition of Ca2+ influx.     

Investigation of the release behavior of diethylhexyl phthalate from the polyvinyl-chloride tubing for intravenous administration

The release behavior of diethylhexyl phthalate (DEHP) from a polyvinyl-chloride (PVC) tube, which is part of an intravenous administration set, was investigated with the coexistence of polysorbate 80 (Tween 80) in various solutions such as physiological saline (PS), distilled water for injection (DWI) and glucose solution (TZ). The cumulative amount of DEHP released after 5 h was in the following order; PS, DWI>50% TZ. From a comparison of the amount of released DEHP and the critical micelle concentration (CMC) of various solutions, the lower the CMC of the solution, the higher the amount of DEHP released from the PVC tubing. When the concentration of Tween 80 was kept constant at 1 mg/ml, the cumulative amount of DEHP released with a flow rate 90 ml/h was higher than that at 60 ml/h. These results suggest that the release of DEHP from the PVC tubing is closely correlated with the interaction of Tween 80 and DEHP such as the formation of micelles, the collision of micelles against the surface of the PVC tubing and the diffusion properties of DEHP and/or Tween 80 in the liquid medium.     

Genistein-induced neuronal apoptosis and G2/M cell cycle arrest is associated with MDC1 up-regulation and PLK1 down-regulation

The aim of the present study is to investigate the effect of genistein on human neuroblastoma SK-N-MC cells. MTT proliferation assay, LDH cytotoxicity assay, flow cytometric analysis, real-time quantitative RT-PCR and western blotting were used to investigate the effect of genistein on cell survival, cellular toxicity, cell cycle progression, and mRNA and protein alterations of selected DNA damage-, cell cycle- and apoptosis-related genes in SK-N-MC cells. Genistein suppressed cell proliferation, increased LDH release and modulated cell cycle distribution through accumulation of cells at G2/M- and S-phase and sub-G0 (cell death) with a concurrent decrease of cells at G0/G1 phase. Genistein increased the MDC1 (Mediator of DNA damage Checkpoint protein 1), p53, p21(waf1/cip1), Cdc2 and Bax mRNA levels in a dose-dependent manner. However, PLK1 (Polo-Like Kinase 1) and Cyclin B1 mRNAs were down-regulated after genistein treatment. Furthermore, Genistein did not alter Chk2 (Checkpoint Kinase 2), Bcl-2 and Cdc25C mRNA levels. On western blotting analyses; genistein increased the protein level of MDC1, p53, p21(waf1/cip1), and Bax in a dose-dependent manner. Genistein also increased the phosphorylation of Chk2 and Cdc25C at Thr-68 and Ser-216, respectively. In addition, consistently with PLK1 down-regulation, the phosphorylation of Cdc25C at Ser-198 was markedly decreased after genistein treatment. Additionally, Chk2, Cdc25C, Cyclin B1, p-Cyclin B1 (Ser-147), and Cdc2 as well as Bcl-2 proteins were down-regulated after genistein treatment. Altogether, these results suggest for the first time the involvement of MDC1 up-regulation after genistein treatment in DNA damage-induced Chk2 activation- and PLK1 down-regulation-mediated apoptosis and cell cycle checkpoint pathways.