不同厂家盐酸二甲双胍片体外溶出度考查

目的：对8个不同厂家的盐酸二甲双胍片进行体外溶出度考查，为临床合理用药提供依据。方法：《中国药典》2005年版规定的溶出度测定法。结果：各厂家产品的溶出参数m除D、F厂与A、H厂有显著性差异（P〈0．05）外，其余均无显著性差异；而T50，Td除B厂与D、F厂，E厂与G厂，C厂与H厂之间无显著性差异（P〉0．05）外，其余均有显著性差异（P〈0．05）。结论 实验结果为临床选药提供了参考。     

不同剂型左氧氟沙星溶出度的测定及比较

目的考察不同厂家不同剂型左氧氟沙星（胶囊、片剂）的体外溶出度,为药品采购及临床用药提供参考。方法采用转篮法进行体外溶出度实验,以紫外分光光度法进行含量测定,计算累积溶出百分率,以威布尔方程拟合溶出参数Ro、Td、m。结果左氧氟沙星胶囊剂及片剂的体外溶出度均符合2005版《中国药典》规定,但片剂与胶囊剂的Td间有显著性差异（P〈0．05）。结论左氧氟沙星片剂溶出度比胶囊快,药品采购及临床用药时应加以注意。     

4厂家左氧氟沙星片溶出度考察

目的:比较4厂家左氧氟沙星片的溶出度,为临床用药提供参考。方法:采用紫外分光光度法,分别测定4厂家左氧氟沙星片不同时间内的累积溶出百分率,并以威布尔公式计算出溶出参数T50、Td、T80、m的值,再对参数进行方差分析。结果:4厂家左氧氟沙星片溶出度均符合2000年版《中国药典》规定,但其T50、Td、T80、m值间均有显著性差异(P<0.01)。结论:有关厂家应严格按照《中国药典》规定控制产品的内在质量,以保证临床用药安全、有效。     

氧氟沙星片剂的溶出度研究

本文采用转篮法对国产及进口几个厂家生产的盐酸氧氟沙星片剂进行了体外溶出度测定，并对其溶出参数（Td、T50、m）进行了统计处理。结果表明：不同厂家的产品之间，其溶出参数有显著性差别（p＜0．001）。     

6厂家左氧氟沙星片质量评价

目的 :考察6厂家左氧氟沙星片的质量。方法 :参照相关标准考察6厂家17个批号左氧氟沙星片质量 ,并采用同一溶出条件考察各样品溶出曲线。结果 :6厂家左氧氟沙星片质量均符合规定 ,但溶出特性、治疗费用均有显著性差异 (P<0 01)。结论 :不同厂家生产的左氧氟沙星片质量有差异 ,拥有专利的原研发厂家药品价格较高 ,但质量较稳定。     

不同厂家盐酸西替利嗪片的体外溶出度比较

目的测定5厂家盐酸西替利嗪片的体外溶出度,为临床用药提供参考。方法采用转篮法测定溶出度,用威布尔分布模型拟合溶出曲线,并对提取形状参数（m）,溶出药物50％所需时间（T50）,溶出药物63．2％所需时间（Td）进行方差分析。结果5厂家盐酸西替利嗪片的含量、含量均匀度及体外溶出度均符合2005年版《中国药典（二部）》的相关规定,不同厂家产品间的溶出参数T50,Td,m有显著性差异（P〈0．01）。结论5厂家盐酸西替利嗪片的溶出度存在差异,临床应用时应加以注意,药监部门应加强生产质量的动态监测和药品生产工艺管理,以保证产品质量的均衡性。     

不同厂家羟乙基芦丁片体外溶出度的考察

对国内4个厂家生产的6批羟乙基芦丁片的体外释放度进行考察,为其质量控制提供参考。采用转篮法和紫外分光光度法进行释放度测定。结果不同厂家产品的溶出参数（T50、Td、T80）有极显性差异（P＜0.01),溶出参数m值均无显性差异（P＞0.05)。经两两Q检验,同一厂家溶出度参数无显性差异,不同厂家（除B1厂外）均无显性差异。因此,必须对羟乙基芦丁片进行溶出度测定,以控制其质量。     

不同厂家格列齐特片溶出度考察

目的 :比较6厂家格列齐特片的溶出度 ,为临床选用提供参考。方法 :采用分光光度法分别测定A、B、C、D、E、F厂格列齐特片的累积溶出度 ,绘制其溶出曲线 ,计算参数T50、Td、m的值 ,并对T50、Td 值进行两两比较。结果 :E厂格列齐特片的T50、Td 值与其它5厂有显著性差异 (P<0 01) ,其余5厂格列齐特片的T50、Td 值间无显著性差异 (P>0 05)。其中 ,E厂格列齐特片在180min时的累积溶出率<75 %,不符合《中国药典》规定 ,其它5厂格列齐特片的溶出度均符合规定。结论 :建议有关厂家对影响制剂溶出度的辅料及生产工艺进行改进 ,以提高产品质量。     

6厂家左旋氧氟沙星不同剂型溶出度考察

目的：对6个厂家不同剂型的左旋氧氟沙星进行溶出度考察。方法：以盐酸溶液（9→1000）为溶出介质，采用紫外分光光度法进行测定。结果：各厂产品溶出参数差异非常显著（P＜0．01）。结论：实验结果为临床选药提供了参考。     

15个厂家盐酸二甲双胍片溶出度的比较

目的：比较15个厂家盐酸二甲双胍片的体外溶出度，为临床用药提供参考。方法：采用转篮法进行体外溶出度实验，以紫外分光光度法进行含量测定，计算累计溶出百分率。以威布尔方程拟合溶出参数，并用方差分析对组间溶出参数进行统计学分析。结果：15个厂家盐酸二甲双胍片的体外溶出度均符合《中国药典》2005年版的规定，但各厂家盐酸二甲双胍片的溶出参数m、T30、T50、Td和T80间存在显著性差异（P〈0．01）。结论：不同厂家盐酸二甲双胍片的溶出参数存在差异，临床用药时应加以注意。     

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.     

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.