阿霉素聚乳酸微球的含量测定

阿霉素（ADM）的含量测定方法国内已报道有很多种,如荧光分光光度法测定明胶磁性微球中阿霉素的含量,紫外分光光度法测定阿霉素磁性明胶微球的含量,反相高效液相色谱一荧光检测法测定阿霉素磁性豪微球等啊。本实验用溶解法将聚乳酸的网状结构破坏后,再采用紫外一可见分光光度法测定聚乳酸微球中阿霉素的含量。该方法快速、准确、结果满意。     

氨甲喋呤铁磁性微球的制备及物理性质测定

目的：制备氨甲喋呤铁磁性微球，探讨工艺条件对成球的影响，并测定微球的粒径，磁性物质和药物的含量以及药物释放度等主要物理性质。方法；以人血白蛋白作载体，磁铁粉作磁响应物质用加热固化法制备抗肿瘤药物ＭＴＸ的磁性微球，显微镜下观察微球形态大小，计算粒径分布，重量法测定磁性物质的含量，紫外分光光度法测定ＭＴＸ含量及体外释放度。     

复方阿霉素磁性白蛋白微球的制备及含量测定

目的：将阿霉素与维拉帕米（ＶＰＭ）制成复方磁性微球制剂以抑制阿霉素耐药性的产生和降低其不良反应。方法：实验采用加热固化制备复方磁性白蛋白微球,用充体法蛊磁粉以紫外和双波长分光光度法分别测定维拉帕米和阿霉素的含量。结果：微球粒径较均匀,收率为７８％,制剂中阿素ＶＰＭ含量分别为０．１５％,１５％。结论：微球的制备及呈测定方法均简单可行。     

磁性靶向紫杉醇微球制备的初步研究

目的：制备磁性靶向紫杉醇微球.方法：以紫杉醇和纳米Fe3O4为材料制备出磁性靶向紫杉醇微球,并利用高分辨透射电子显微镜（HRTEM）观察微球的形貌,同时采用紫外可见分光光度法测定微球的载药量和包封率.结果：磁性靶向紫杉醇微球的载药量为3.013%,包封率为35.26%.结论：通过实验研究制备了磁性紫杉醇微球,具有靶向定位功能,形成一种磁靶向给药系统.     

紫外分光光度法测定胰岛素注射液的含量

胰岛素是治疗糖尿病的重要药物,胰岛素制剂的含量测定一直都采用生物测定法。近年来又发展了高效液相色谱法、放射免疫法和酶免疫法等。但这些方法往往受到某些条件的限制。紫外分光光度法是药物制剂含量测定中常用的方法之一,Shan-Yang Lin曾用紫外分光光度法在波长220nm处测定了胰岛素——聚乳酸微球和乙基纤维素微球中胰岛素的含量。本试验探索了用紫外分光光度法来测定胰岛素及其注射液含量的方法。     

多柔比星磁性葡聚糖微球的制备及特性检测

目的:制备多柔比星磁性葡聚糖微球并检测其特性。方法:采用吸附法制备多柔比星磁性葡聚糖微球。高倍显微镜观察微球粒径大小及形态,紫外分光光度法检测微球中多柔比星的含量,测定微球磁吸附率,计算求和值 S,确定最佳投料比(药物:载体),绘制药物微球体外释放曲线。结果:制备的多柔比星磁性葡聚糖微球最佳投料比为1:15,磁吸附率为100%。微球外形圆整,分散性好。多柔比星30 min 释放28%;60min 释放45%;6h 释放65%。结论:制备的多柔比星磁性葡聚糖微球缓释性好,磁响应性强,可作为一种治疗顽固性疼痛的靶向神经损毁剂。     

亚甲蓝磁性明胶微球的制备及特性试验

目的：制备亚甲蓝磁性明胶微球并检测其特性。方法：采用乳化-交联法制备亚甲蓝磁性明胶微球，高倍镜观察微球粒径大小及形态，紫外-可见分光光度法检测微球中亚甲蓝的含量及其体外释放规律。结果：亚甲蓝磁性明胶微球粒径38—50μm，在4000GS的磁场下动作距离为70—80mm，载药量为9．8％，180min体外累积释放量为90％。结论：亚甲蓝磁性明胶微球是一种新剂型，制备工艺简便，具有较好的磁响应性和一定缓释性。     

莪术油明较微球剂的含量测定

目的：研究莪术油明胶微球的含量测定方法。方法：莪术油明胶微球用胰酶-超声法消解,硫酸－香草醛显色后,用可见－分光光度法进行测定,结果：胰酶的用量,超声时间,消解时间,对测定均有影响。结论：所建立的方法准确,可靠,适用于莪术油明磁微球剂的含量测定。     

庆大霉素聚氰基丙烯酸丁酯毫微球冻干注射剂的制备及其特性

用乳化聚合法制备庆大霉素聚氰基丙烯酸丁酯毫微球，经冷冻干燥制成冻干型注射剂。用一阶导数分光光度法测定药物的结合率和载药量；以浊度作为评价冻干毫微球重分散性能的指标，筛选配方和工艺；用透射电镜测定了冻干前后粒度分布的变化；对体外释药进行了考察；还对毫微球的其他理化特性进行了测定。     

喷雾干燥牛血清白蛋白微球中地塞米松磷酸钠和5-氟尿嘧啶的含量测定

用等吸收双波长紫外分光光度法测定了喷雾干燥牛血清白蛋白微球中地塞米松磷酸钠和 ５氟尿嘧啶的含量。回收率及重现性均好。方法快捷、准确。     

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.     

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.     

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.