扑热息痛缓释微丸的制备

目的制备扑热息痛缓释微丸,并对其体外释药情况进行研究。方法采用挤出滚圆法制备扑热息痛素丸,在流化床内采用丙烯酸树脂水分散体对其包衣,制备扑热息痛缓释微丸。用释放度测定法考察影响药物释放的各种因素,对包衣微丸体外释药机理进行研究。结果包衣材料为丙烯酸树脂NE30D(Eudragit NE30D),质量分数增加6%时包衣微丸在pH 6.18的磷酸盐缓冲液中呈现良好的缓释效果,体外释药过程基本符合Higuchi方程:Y=31.213t1/2+0.425(r=0.993 2)。结论采用挤出滚圆法和丙烯酸树脂流化床包衣,成功地制备了扑热息痛缓释微丸,其体外释药缓慢、持续平稳。     

氧化苦参碱缓释胶囊的制备及体外释放特性研究

目的制备氧化苦参碱24h缓释胶囊并对其体外释放特性进行研究。方法采用流化床包衣法,先将氧化苦参碱与聚乙烯吡咯烷酮溶于85%乙醇中,喷于空白丸芯制成含药微丸,再以乙基纤维素水分散体（Surelease）作为主要包衣材料进行包衣,得微丸装胶囊。建立体外分析方法并进行体外释药模型拟合。结果该缓释胶囊的释药符合Higuchi方程,具有缓释制剂的体外溶出特征。结论苦参碱缓释胶囊制备工艺简单,释药稳定,具备优良缓释制剂的特征。     

盐酸青藤碱缓释微丸的研制

目的：制备盐酸青藤碱缓释微丸，并对其体外释药行为进行研究。方法：采用离心造粒技术制备盐酸青藤碱素丸，在流化床内采用丙烯酸树脂水分散体对其包衣，制备盐酸青藤碱缓释微丸。对包衣材料种类、配比及用量进行选择，对包衣微丸体外释药机理进行研究。结果：包衣材料Eudragit NE30D增重5％时，包衣微丸在水中呈现良好的缓释效果，体外释药过程基本符合Higuchi方程：Y=0．0938＋0．0846t（r=0．9965）。结论：采用离心造粒技术和丙烯酸树脂流化床包衣，成功地制备了盐酸青藤碱缓释微丸，其体外释药缓慢、平稳。     

法罗培南钠缓释微丸的制备及体外释放特性考察

目的制备法罗培南钠缓释微丸,并对其体外释药特性进行研究。方法挤出滚圆法制备载药丸芯;以乙基纤维素N-100为包衣材料,以聚维酮k30为致孔剂,流化床包衣制备法罗培南钠缓释微丸;考察包衣增重、致孔剂用量等因素对缓释微丸释放度的影响,并考察其体外释药特征及释药机制。结果所制备的微丸有明显的缓释特征,体外释放符合Higuchi释药动力学方程。结论制备的法罗培南钠缓释微丸具有较理想的体外缓释效果。     

甲磺酸双氢麦角毒碱缓释微丸的研制

目的：制备甲磺酸双氢麦角毒碱缓释微丸,并研究其体外释药情况。方法：采用离心造粒法制备甲磺酸双氢麦角毒碱素丸,在流化床内采用丙烯酸树脂水分散体对其包衣,制备甲磺酸双氢麦角毒碱缓释微丸。用释放度测定法考察影响药物释放的各种因素,研究包衣微丸体外释药机制。结果：所制微丸体外释药过程基本符合Higuchi方程：Y=0．41＋29．22t1/2（r=0．9782）。结论：甲磺酸双氢麦角毒碱缓释微丸体外释药缓慢、平稳。     

法莫替丁缓释微丸的悬浮包衣法制备

采用淀粉和蔗糖为赋形剂制备法莫替丁含药微丸，以乙基纤维素为包衣材料，采用悬浮包衣法制备了法莫替丁缓释微丸，并用正交设计筛选出了最佳制备工艺参数。释放度研究结果表明：在进风温度为45℃，喷雾压力为147kPa及输液速度为10ml/min的条件下进行包衣，可制得在12h内释药符合Higuchi模型动力学过程的缓释微丸。     

离心造粒法制备罗红霉素缓释小丸

目的：制备罗红霉素缓释小丸,并对其体外释药情况进行研究。方法：采用离心造粒技术制备微晶纤维素空白丸核和罗红霉素含药丸芯,以聚丙烯酸树脂Eudragit NE30D为包衣液制成膜控缓释小丸,考察包衣增重、致孔剂用量等因素对缓释小丸释放度的影响。结果：通过单因素考察确定了包衣液处方,所制备的小丸具有明显的缓释特征,体外释药过程符合一级动力学模型。结论：制备的罗红霉素缓释小丸符合12h缓释要求。     

含药树脂微囊法制备口服缓释混悬液Ⅰ.右美沙芬口服缓释混悬液

采用含药树脂微囊法制备了右美沙芬口服缓释混悬夜，研究了影响含药树脂药物吸附和释放的因素及体外释药和健康志愿者体内的药动学。结果表明该混悬液在服用12h后，尚有101．9ng／m1的有效血药浓度。     

阿昔洛韦缓释微丸的研制

目的制备阿昔洛韦缓释微丸,并对其体外释药情况进行研究。方法采用离心造粒技术制备阿昔洛韦素丸,在流化床内采用丙烯酸树脂水分散体对其包衣,制备阿昔洛韦缓释微丸。对包衣材料种类、配比及用量进行选择,对包衣微丸体外释药机理进行研究。结果包衣材料EudragitNE30D与L30D-55质量比为12∶1、增重8%时包衣微丸在pH6.8的磷酸盐缓冲液中呈现良好的缓释效果,体外释药过程基本符合Higuchi方程:Y=0.405+30.021t(r=0.9912)。结论采用离心造粒技术和丙烯酸树脂流化床包衣,成功地制备了阿昔洛韦缓释微丸,其体外释药缓慢、持续、平稳。     

克拉霉素缓释包衣微丸的制备及体外释放度研究

目的制备克拉霉素缓释包衣微丸,并对其体外释放度进行考察。方法采用挤出滚圆技术制备克拉霉素含药微丸。以优化的丙烯酸树脂类Eudragit NE30D和Eudragit L30D-55混和水分散体为包衣材料,采用流化床包衣技术,制备缓释包衣微丸。考察自制缓释微丸的体外释药速率,并与市售的克拉霉素缓释胶囊进行比较。结果通过释药行为的评价,得到优化的包衣处方为5∶1的Eudragit NE30D和Eudragit L30D-55混和包衣材料,其体外释放行为在不同的pH溶出介质中与市售制剂产品没有明显差异,体外释药过程符合一级释放模型。结论采用挤出滚圆和流化床技术,以及优化的Eudragit NE30D和Eudragit L30D-55混和水分散体包衣材料,成功制备了克拉霉素缓释包衣微丸。     

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.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.     

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.