顺铂壳聚糖微球的制备及特性研究

对顺铂壳聚糖微球的制备、载药量、大小及分布、形态及表面状态、体外释放及降解性进行了研究。微球用乳化-化学交联技术制备,平均粒径为74.80μm,顺铂含量为20.83%±0.36%。电镜扫描显示,微球球形圆整,表面粗糙。生理盐水中放置1h微球轻微溶胀,其体外释药符合一级方程,微球经⁶⁰Co辐射灭菌达到无菌要求。犬肝动脉栓塞后一个月,病理切片可见栓塞区仍有壳聚糖微球存在。     

顺铂明胶微球的研制及相关生物学特性

目的 研制包裹有顺铂的颗粒型可降解性栓塞剂。方法 采用改良的双相乳化冷凝聚合法制备顺铂明胶微球，以原子吸收光谱分析为基础，测定顺铂明胶微球的包裹率、载药率及体外释药特性。结果 顺铂明胶微球颗粒直径均匀，药物包裹率91％。载药率17.4%，体外4b内缓释96％。结论 本法制得的顺铂明胶微球性质稳定，微球降解速率及药物释放速度基本符合临床要求。     

栓塞制剂—顺铂微球的研究

本文用非生物降解材料乙基纤维素制备了顺铂微球,用于肿瘤的栓塞治疗。进行的体外制剂学研究、动物体内外毒性考察、栓塞实验及人体临床应用结果显示:顺铂微球具有显著的栓塞肿瘤血管之效果,且可缓解,降低全身毒性,实现靶向给药之目的。     

靶向给药系统—顺铂肝动脉栓塞微球的研究

用改良的油/油(o/o)溶媒蒸发法制备的顺铂-乙基纤维素非生物降解微球作为肝动脉栓塞化疗的新剂型。试用 TLC 和 UV 比值(A_(301nm)/A_(247nm)结合,301nm 处的吸光度进行了药物含量及体外稳定性的检测。兔肝动脉灌注顺铂微球后血清铂浓度的上升与下降速度均较灌注顺铂溶液缓慢,兔灌注顺铂微球后,组织铂含量较低,衰减速度也较慢。对原发性肝癌病人用顺铂微球和临床常规栓塞治疗的比较表明,疗效有显著差异。     

载环孢素A海藻酸钙-壳聚糖微球的制备及体外释放特性

目的:针对角膜移植术后免疫抑制治疗需求,制备眼部局部给药的小粒径载环孢素A缓释微球,并进行体外释放考察。方法:以海藻酸钠、壳聚糖为载体材料,采用静电液滴工艺,通过向制备体系添加表面活性剂,制备小粒径载环孢素A微球,设计正交试验优化处方工艺,扫描电镜观察微球表面形态,动态透析法考察微球的体外释放特性。结果:所制微球形态良好,粒径分布窄,平均粒径为(12.4±0.8)μm,包封率为(82.8±1.8)%,载药量为(50.1±1.2)%,体外释放行为用Higuchi方程拟合效果最好。结论:采用静电液滴工艺,通过减小制备体系的表面张力,制备了球形度优良、粒径小、包封率和载药量较高的载环孢素A的壳聚糖-海藻酸盐缓释微球,所得制剂的体外释药规律服从扩散机制。     

顺铂白芨胶微球在犬体内的药动学

目的研究顺铂白芨胶微球肝动脉灌注后体内药动学过程,判别其体内靶向性和缓释性能,为其临床治疗提供科学依据.方法犬麻醉后经股动脉穿刺引入5F单弯血管造影导管,透视下插至肝动脉分别灌注顺铂白芨胶微球和顺铂注射液,不同时间点采血,通过原子吸收光谱法检测血药浓度,通过DAS2.0药动学计算软件计算顺铂不同剂型在犬体内的药动学参数.结果白芨胶微球中的顺铂和顺铂注射液在犬体内的药动学模型为二室模型,其中顺铂注射液药动学参数t1/2α(2.3±0.9)h,t1/2β(75.1±2.0)h,AUC(0-t)(49.2±1.8)mg·h·L-1,AUC(0-∞)(64.3±3.8)mg·h·L-1,MRT(0-t)(58.0±1.9)h,MRT(0-∞)(120.7±10.2)h,C(max)(1.72±0.17)mg·L-1,t(max)(0.057±0.098)h;顺铂白芨胶微球的顺铂药动学参数t1/2α(11.5±4.3)h,t1/2β(143.2±42.4)h,AUC(0-t)(31.2±1.5)mg·h·L-1,AUC(0-∞)(47.4±6.O)mg·h·L-1,MRT(0-t)(62.1±1.7)h,MRT(0-∞)(152.4±48.2)h,C(max)(0.77±0.05)mg·L-1,t(max)(1.30±0.27)h.结论顺铂白芨胶微球在体内栓塞治疗的同时,通过其被动靶向作用在肝组织缓慢释放药物,降低其在外周血液和组织的药物浓度,长时间提高其在病灶部位的有效浓度,达到提高临床治疗效果,减少其不良反应的目的.     

顺铂壳聚糖微球犬肝动脉栓塞的研究

研究了顺铂壳聚糖微球经犬肝动脉栓塞后体内药动学过程、靶向特征及栓塞效果,并初步应用于临床。经肝动脉给药材24h,栓塞组肝组织顺铂浓度为顺铂溶液组的2.92倍,而其血浓峰值及药时曲线下面积(AUC)均低于溶液组。血管造影显示,微球栓塞后肝脏外周血管明显减少,病理切片可见栓塞部位组织坏死。微球栓塞后GPT,GOT及ALP有一过性升高,3周后基本恢复正常;微球临床初步应用效果较好。结果表明,以壳聚糖为载体材料制备的微球是一种良好的癌症化疗栓塞剂。     

白及胶栓塞微球的制备

目的 制备白及胶微球并探讨主要影响因素. 方法 采用乳化、冷凝固化、化学交联技术首次制备出白及胶微球,考察化学交联剂浓度和交联时间对微球影响, 通过对微球吸水率检测其溶胀度;研究微球与红细胞在37 ℃放置24 h, 观察红细胞的形态研究微球的血液相容性;采用⁶⁰Co进行照射灭菌. 结果 制备的白及胶微球平均粒径为54.36 μm , 粒径范围50～90 μm占总数的78.37 %; 初步确定化学交联剂浓度为3%, 交联时间2 h;微球在pH值=7.4的缓冲液中有一定的溶胀性; 血液相容性良好. 2.5×10 4Gy 的⁶⁰Co可以达到灭菌的要求. 结论 通过正交实验获得的制备工艺不仅可以制备临床需要的白及胶微球, 同时也为制备白及胶含药微球提供参考的实验条件.     

星点设计-效应面法优化去甲斑蝥素壳聚糖-丝素蛋白栓塞微球的制备

目的:制备去甲斑蝥素壳聚糖-丝素蛋白栓塞微球(Norcantharidin-loaded chitosan-fibroin micro-spheres for embolization,NCTD-CS-SF-MS),考察其包封率,载药量及外观形态,并对其体外释放特性进行考察。方法:采用乳化-交联固化法制备NCTD-CS-SF-MS,其中以液体石蜡为油相,壳聚糖(chitosan CS)与丝素蛋白(silk fibroin SF)的物理混合溶液为水相,Span-80为乳化剂,戊二醛为交联剂。星点设计-效应面法优化制备工艺,扫描电镜观察微球表面形态及X-射线衍射(XRD)、差示量热扫描(DSC)表征微球特性。采用体外动态透析法测定微球在不同介质条件下的释药性能。结果:制备的微球形态圆整,大小均匀,平均粒径约(184±5)μm,载药量(15.08±2.85)%,包封率(27.46±1.25)%。微球在0.1 mol.L-1 HCl、PBS(pH=7.4)和生理盐水中的释放均遵循Weibull方程。结论:所优化的制备工艺简单易行,缓释作用显著。     

栓塞颌面血管瘤动脉的平阳霉素白蛋白微球的制备

目的　制备平阳霉素白蛋白微球 ,提高平阳霉素抑制血管瘤的作用。方法　以化学交联法在单因素考察的基础上进行均匀试验设计 ,筛选出栓塞血管瘤动脉的平阳霉素白蛋白微球的最佳制备工艺 ,考察了微球的形态和粒度分布及体外释药特性。结果　化学交联法制得的微球表面圆整、光滑 ,平均粒径为 83.6± 10 .5 μm ,药物平均包封率为 34.3% ;载药量为4 0 .2 % ;释药特性可用Higuichi和单指数方程描述。结论　以化学交联法制备的平阳霉素白蛋白微球粒径符合栓塞要求 ,体外具有明显缓释效果。     

Synthesis,Cytotoxicity and Antileishmanial Activity of Some N-(2-(indol-3-yl)ethyl)-7-chloroquinolin-4-amines

We report herein the condensation of 4,7-dichloroquinoline (1) with tryptamine (2) and D-tryptophan methyl ester (3) . Hydrolysis of the methyl ester adduct (5) yielded the free acid (6) . The compounds were evaluated in vitro for activity against four different species of Leishmania promastigote forms and for cytotoxic activity against Kb and Vero cells. Compound (5) showed good activity against the Leishmania species tested, while all three compounds displayed moderate activity in both Kb and Vero cells.     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Lung disease and PKCs

The lung offers a rich opportunity for development of therapeutic strategies focused on isozymes of protein kinase C (PKCs). PKCs are important in many cellular responses in the lung, and existing therapies for pulmonary disorders are inadequate. The lung poses unique challenges as it interfaces with air and blood, contains a pulmonary and systemic circulation, and consists of many cell types. Key structures are bronchial and pulmonary vessels, branching airways, and distal air sacs defined by alveolar walls containing capillaries and interstitial space. The cellular composition of each vessel, airway, and alveolar wall is heterogeneous. Injurious environmental stimuli signal through PKCs and cause a variety of disorders. Edema formation and pulmonary hypertension (PHTN) result from derangements in endothelial, smooth muscle (SM), and/or adventitial fibroblast cell phenotype. Asthma, chronic obstructive pulmonary disease (COPD), and lung cancer are characterized by distinctive pathological changes in airway epithelial, SM, and mucous-generating cells. Acute and chronic pneumonitis and fibrosis occur in the alveolar space and interstitium with type 2 pneumocytes and interstitial fibroblasts/myofibroblasts playing a prominent role. At each site, inflammatory, immune, and vascular progenitor cells contribute to the injury and repair process. Many strategies have been used to investigate PKCs in lung injury. Isolated organ preparations and whole animal studies are powerful approaches especially when genetically engineered mice are used. More analysis of PKC isozymes in normal and diseased human lung tissue and cells is needed to complement this work. Since opposing or counter-regulatory effects of selected PKCs in the same cell or tissue have been found, it may be desirable to target more than one PKC isozyme and potentially in different directions. Because multiple signaling pathways contribute to the key cellular responses important in lung biology, therapeutic strategies targeting PKCs may be more effective if combined with inhibitors of other pathways for additive or synergistic effect. Mechanisms that regulate PKC activity, including phosphorylation and interaction with isozyme-specific binding proteins, are also potential therapeutic targets. Key isotypes of PKC involved in lung pathophysiology are summarized and current and evolving therapeutic approaches to target them are identified.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.     

Gender-related symptoms and correlates of alcohol dependence among men and women with a lifetime diagnosis of alcohol use disorders

This study explored gender-related symptoms and correlates of alcohol dependence in a crosssectional study of 150 men and 150 women with a lifetime diagnosis of alcohol use disorders (AUD). Participants were recruited in equal numbers from treatment settings, correctional centres and the general community. Standardized measures were used to determine participants' use of substances, history of psychiatric disorders and psychosocial stress, their sensation seeking and family history of substance use and mental health disorders. Multivariate analyses were used to detect patterns of variables associated with gender and the lifetime severity of AUD. Men had a longer history of severe AUD than women. Women had similar levels of alcohol dependence and medical and psychological sequelae as men, despite 6 fewer years of AUD. More women than men had a history of severe psychosocial stress, severe dependence on other substances and antecedent mental health problems, especially mood and anxiety disorders. There were differences in family history of alcohol-related problems approximating same-gender aggregation. The severity of a lifetime AUD was predicted by its earlier age at onset and the occurrence of other disorders, especially anxiety, among both men and women. The limitations in the generalizability of these findings due to sample idiosyncrasies are discussed.