In vitro stability and permeability studies of liposomal delivery systems for a novel lipophilic endomorphin 1 analogue

The influence of inlet air humidity variations on fluid bed drying end-point detection was the primary focus here. Various drying end-point criteria based on temperature and humidity measurements were compared. Seasonally changing inlet air humidity affects the moisture content of the finished granules, as long as the drying process remains unchanged. However, a specific moisture content of the finished granules is commonly desired after fluid bed drying. When experimental batches of varying inlet air humidity were compared at the beginning of the drying phase, the temperature of the granules increased linearly as the humidity of the inlet air increased. This effect causes variation in moisture contents of the final granules of different batches when the fixed temperature of the mass is used as an end-point criterion. With varying inlet air humidity, the often used ΔT temperature difference method resulted in more precise estimation of the drying end-point than the constant temperature criterion. In this study new insights were found into the correlation between moisture content and temperature of the fluidising mass. Fluidisation activity greatly affected detection of drying end-point. Use of the ΔT criterion requires proper fluidisation throughout the process.     

Form conversion of anhydrous lactose during wet granulation and its effect on compactibility

The purpose of this study was (a) to evaluate the factors affecting the form conversion of anhydrous lactose to the monohydrate form during wet granulation using water as the granulating agent and (b) study the effect of lactose form conversion on its compaction properties. A two-level full factorial design with two center points was used to evaluate the factors affecting form conversion. The three variables evaluated were percentage of microcrystalline cellulose (low 0 and high 20), water to intragranular solids ratio (low 0.10 and high 0.18) and drying conditions (tray drying and fluid bed drying). The presence of microcrystalline cellulose in the formulation did not provide any benefit in reducing the percent lactose conversion. But, the conversion was significantly reduced by decreasing the amount of water added to the granulation and/or by decreasing the drying time, using a fluid bed dryer compared to a tray dryer. In the second part of the study, complete conversion of the anhydrous lactose to monohydrate was achieved by storing the anhydrous form under 25 °C/97% RH for 4 weeks. Physical characterization (compactibility, surface area and surface morphology) was performed on the form converted material and compared to the as received anhydrous lactose. The physical characterization results indicated that even though anhydrous lactose undergoes complete form conversion to monohydrate form under high humidity and/or during wet granulation, it retains its inherent higher as received material compactibility and the BET surface area and porosity of the form converted material are higher than that of the as received anhydrous lactose.     

盐酸二甲双胍流化床制粒工艺的影响因素研究

摘 要 目的：研究流化床制粒工艺参数对盐酸二甲双胍颗粒物理性质的影响。方法: 以盐酸二甲双胍颗粒物理性质作为评价指标,采用单因素试验法分别考察了流化床制粒过程中的设备因素（喷枪高度、喷枪孔径）和工艺参数（黏合剂用量、进风温度、进风速度、进液速度、雾化压力）对其产生的影响。结果: 设备因素中喷枪高度、喷枪孔径对颗粒物理性质影响较小,工艺参数中黏合剂用量、进风温度、进风速度、进液速度、雾化压力对颗粒物理性质影响均较大。结论: 流化床制粒工艺中黏合剂用量、进风温度、进风速度、进液速度、雾化压力对盐酸二甲双胍颗粒会产生较大影响,可按照颗粒性质要求进行控制。     

中心复合设计-效应面法优化盐酸米诺环素缓释片处方

摘 要 目的：制备盐酸米诺环素缓释片并优化处方。方法: 采用干法制粒压片工艺制备盐酸米诺环素缓释片,以羟丙甲纤维素E50（HPMC E50）和羟丙甲纤维素K100LV（HPMC K100LV）的用量为考察因素,1,2,4,8 h的累积释放度为评价指标,采用中心复合设计 效应面法优化盐酸米诺环素缓释片的处方,并通过体外释放度比较自研片剂和原研片剂在4种释放介质中的溶出相似性。结果: 盐酸米诺环素缓释片处方中HPMC E50和HPMC K100LV的用量分别为35 mg和70 mg,制得的缓释片在各时间点的释放度与原研片剂相似,4种释放介质中自研片剂和原研片剂的溶出相似因子f₂分别为79.06、84.62、75.46和72.95。结论:采用中心复合设计 效应面法优化的盐酸米诺环素缓释片处方制得的片剂体外释放度符合要求,为下一步的工业化生产提供依据。     

响应面法优化罗麦颗粒成型工艺的研究

摘 要 目的：优化罗麦颗粒剂的最佳成型工艺。方法: 以合格颗粒收率及吸湿性为指标对赋形剂的种类进行筛选,通过对制粒效果的考察,优选赋形剂的最佳混合比例。以合格颗粒收率、溶化性、吸湿性、感官评价的总评“归一值”作为评价指标,选取辅料倍数、乙醇浓度、柠檬酸用量为主要影响因素,采用3因素5水平中心组合设计—响应面法优化罗麦颗粒成型工艺。结果: 确定了糖粉和麦芽糊精为颗粒的赋形剂,且糖粉和麦芽糊精的最佳混合比例为3∶1。罗麦颗粒的最佳成型工艺是赋形剂用量为提取物的5倍量,润湿剂为85%乙醇,柠檬酸含量为0.3%。结论:运用中心组合设计—响应面法制备所得的罗麦颗粒具有合格收率高、吸湿性小、溶化性好、口感柔和且服用量适中等优点,表明优化罗麦颗粒湿法制粒的工艺合理、可行。     

枕骨内板的蛛网膜颗粒(附6例报告)

目的:探讨枕骨蛛网膜颗粒压迹的CT及MR表现,以与病理性缺损相区别。方法:本组6 例均进行了CT及MR平扫及MR增强扫描。结果:枕骨蛛网膜颗粒压迹位于枕内粗隆下方平面,多为双侧性(4例),也可为单侧性(2例),CT扫描示枕骨局限性骨质缺损由内板伸入板障,少数可累及外板,境界清楚,无硬化边,脑脊液密度:MR各序列为脑脊液信号,并与蛛网膜下腔相通。结论:枕骨蛛网膜颗粒压迹CT表现有特点,MR表现更具特征,可确定诊断     

偎脓长肉理论指导下药疮交互作用机制探讨

偎脓长肉是中医治疗疮面的特色外治理论之一.邪腐已去应用生肌类药物外敷疮面促使"脓"生,可保护疮面、促进愈合.中药偎出之脓属"津液"范畴,在药偎脓生过程中药物和疮面充分作用,药物有效成分主动促进疮面发生一系列的微环境改变.药物作用于疮面后,疮面产生脓,使得药物与疮面形成了温度、湿度适宜的微环境,有利于药物有效成分的释放及...     

水提醇沉法中醇沉浓度对板蓝根泡腾片制备过程的影响

目的:研究水提醇沉法中醇沉浓度对板蓝根泡腾片制备过程的影响.方法:考察不同醇沉浓度对板蓝根浸膏得率、指标成分转移率、提取物粉体学性质、制备工艺的影响.结果:醇沉浓度对板蓝根浸膏得率、腺苷转移率、浸膏饱和吸湿量、泡腾片崩解时间等无显著性影响,但对喷雾干燥工艺、干法制粒工艺有明显影响.结论:水提醇沉法中醇沉浓度对板蓝根泡腾片制备过程有明显影响,提示选择醇沉浓度时应当根据实验目的,整个制剂过程的系统试验结果予以确定.     

Expression of vascular endothelial growth factor in exuberant tracheal granulation tissue in children

Prolonged tracheotomy and endotracheal intubation often induce symptoms of airway obstruction and delay decannulation and extubation. Bronchoscopic examination of patients undergoing these treatments usually shows the presence of exuberant (pseudopapillary or nodular) granulation tissue occupying the airway lumen. An immunohistochemical analysis was undertaken of vascular endothelial growth factor (VEGF) expression in exuberant tracheal granulation tissue (n=17) obtained from children treated with prolonged tracheotomy or endotracheal intubation. Increased levels of VEGF protein and mRNA were expressed mainly by tracheal epithelial cells that migrated to cover the granulation tissue and partly by pericapillary macrophages in this tissue, whereas normal tracheal epithelium did not express VEGF. The VEGF expression level correlated significantly with the severity of the exuberant granulation tissue response (p=0·0018). As VEGF induces angiogenesis and vascular permeability, characteristics of granulation tissue, and plays a pivotal role in granulation tissue development, enhanced VEGF expression may be involved in the development of exuberant tracheal granulation tissue. Copyright © 1999 John Wiley & Sons, Ltd     

结肠靶向空白微丸制备工艺的研究

目的采用离心包衣造粒法制备结肠靶向空白微丸。方法采用离心包衣造粒机制备空白丸芯,以蒸馏水为粘合剂,以产率、粒径分布、表面形态和圆整度为微丸丸芯质量评价指标,优化工艺条件。以Eudragit S100为包衣材料对空白微丸进行包衣,并初步考察其在模拟胃肠道的体外溶解性能。结果微晶纤维素(MCC)为制备微丸丸芯的优选辅料。制备空白微丸的最佳工艺条件为:主机转速22.00 Hz,风机转速22.00 Hz,喷气压力0.15 MPa,供粉速度15～20 r/min,喷浆流量8～40 mL/min,滚圆时间4 min。结论以Eudragit S100为包衣材料制备的空白微丸可以达到在结肠定位释放的目的。