盐酸小檗碱片剂与胶囊剂体外溶出度考察

目的　对国内 6个不同厂家生产的盐酸小檗碱片及胶囊进行了体外溶出度考察。方法　按《中华人民共和国药典》2 0 0 0年版[1] 溶出度测定法第 2法 ,测定盐酸小檗碱片及胶囊的溶出度 ,提取参数 (T50 、Td、m) ,并对参数进行相关性研究。结果　除D厂的片剂的溶出度不符合药典规定外 ,其余 4个厂的片剂及F厂的胶囊在 45min时的溶出量均大于 70 %。结论　表明各厂家的产品溶出参数存在显著性差异 (P <0 0 1)。     

美洛昔康片剂与胶囊剂溶出度的比较

目的　测定 5个不同厂家的美洛昔康片剂与胶囊剂的溶出度 ,考察产品质量。方法　采用紫外分光光度法测定美洛昔康片剂与胶囊剂的溶出度。结果　 5个不同厂家的美洛昔康片剂及胶囊剂 4 5min内均溶出 70 %以上 ,溶出度参数T50 、Td、T80 、m及溶出速率常数Kr均存在显著性差异 (P <0 0 1)。结论　不同厂家产品的内在质量存在差异 ,提示临床用药时应加以注意     

8个不同厂家盐酸洛美沙星胶囊体外溶出度比较

目的：比较8个不同厂家生产的盐酸洛美沙星胶囊的体外溶出情况,以考察产品质量。方法：采用转篮法（转速为100r／min）进行体外溶出度试验,以紫外分光光度法测定洛美沙星的含量,分别以盐酸溶液（0．1mol／L）、水、磷酸盐缓冲液（pH6．8）和醋酸盐缓冲液（pH4．0）为溶出介质,测定盐酸洛美沙星胶囊的溶出度。结果：8个厂家的盐酸洛美沙星胶囊在盐酸溶液（0．1mol／L）的溶出介质中30min溶出量均达到80％以上,在其他不同溶出介质中溶出差异大。结论：不同厂家产品质量和生产工艺存在差异。     

盐酸小檗碱片剂与胶囊剂体外溶出度考察

目的 对国内6个不同厂家生产的盐酸小柒碱片及胶囊进行了体外溶出度考察。方法 按《中华人民共和国药典》2000年版^[1]溶出度测定法第2法，测定盐酸小檗碱片及胶囊的溶出度，提取参数(T50、Td、m)，并对参数进行相关性研究。结果 除D厂的片剂的溶出度不符合药典规定外，其余4个厂的片剂及F厂的胶囊在45min时的溶出量均大于70％。结论 表明各厂家的产品溶出参数存在显性差异(P＜0．01)。     

氟康唑胶囊和片剂溶出度考察

目的:考察氟康唑胶囊和片剂的溶出度.方法:采用浆法测定溶出度,以盐酸溶液(9-1000)作为溶出介质,转速80r·min-1,温度(37.0±0.5)℃;用紫外分光光度法测定含量.结果:四个不同厂家的氟康唑胶囊和片剂溶出度均符合中国药典2000年版规定,但不同厂家制剂溶出度稳定性存在差异.结论:此方法可用于氟康唑口服剂型的溶出度监测.     

氧氟沙星胶囊剂溶出度的测定

目的　采用转篮法测定氧氟沙星 (OFL X)胶囊的体外溶出度 ,以建立其溶出度的测定法。方法　按《中国药典》2 0 0 0年版溶出度的测定法测定 OFL X胶囊的溶出度。结果　实验数据根据威布尔分布模型计算出 T50 、Td 及 m。结论　方差分析表明 :不同厂家产品溶出度呈显著性差异 (P <0 .0 1)。 15 min时的累积溶出量之间无显著性差异 (P >0 .0 5 ) ,且符合《中国药典》2 0 0 0年版规定。     

5种罗红霉素胶囊的溶出度考察

以 0 .1mol/L盐酸 -5%乙醇为溶出介质 ,采用硫酸显色的方法 ,对国内 5种不同厂家的罗红霉素胶囊进行溶出度考察。结果表明 ,5种胶囊的含量均大于 95% ,但溶出速率却有非常显著性差异 (P <0 .0 1 )。其中C胶囊溶出最快 ,A胶囊溶出最慢 ,提示我们在选择药品时应重视溶出度检查     

盐酸雷尼替丁胶囊体外溶出度考察

目的 对不同厂家、不同批号的盐酸雷尼替丁胶囊进行溶出度考察.方法 以蒸馏水为溶出介质,采用转篮法对3个厂家4个批号的盐酸雷尼替丁胶囊进行溶出度测定,测得结果用Weibull分布模型提取参数进行方差分析,并采用相似因子法评价不同厂家药品溶出度的相似程度.结果 不同厂家的药品溶出参数存在显著性差异（P＜0.01）;相似因子分析发现不同厂家药品溶出度存在差异,同一厂家不同批号药品溶出度相似.结论 生产单位应对产品进行溶出度检查,并与国内外同类产品进行溶出度比较,以便更好地控制药品质量.     

3种不同厂家奥美拉唑胶囊体外溶出度的比较

目的比较3种不同厂家奥美拉唑胶囊的体外溶出度。方法溶出度测定采用转篮法，含量测定采用高效液相色谱法。结果3种不同厂家奥美拉唑胶囊的耐酸力及在pH值68溶出递质中的体外溶出度、溶出参数均差异无显著性(P＞005)，而在pH值58溶出递质中的体外溶出度差异有显著性(P＜005)。结论3种不同厂家奥美拉唑胶囊存在质量差异。     

尼群地平片溶出度测定

目的采用不同方法考察市售尼群地平口服片剂和软胶囊的溶出度 ,并提出尼群地平溶出度检查的标准。方法用含不同浓度的十二烷基硫酸钠 (SDS)醋酸盐缓冲液 (pH 4 5 )为溶出介质 ,采用紫外分光光度法检查 ,比较不同厂家尼群地平片和尼群地平软胶囊的体外溶出度。用相似因子法对片剂溶出度数据进行统计分析。结果用 0 3 %SDS醋酸盐缓冲液 (pH 4 5 ) ,除B片和D片之间的 (B片 D片 )相似因子F2 >5 0外 ,其余的F2 ≤ 5 0 ,可以显示出不同厂家生产的尼群地平片的溶出度差异。而用 0 1 %SDS醋酸盐缓冲液可以显示出尼群地平软胶囊与片剂的溶出度差异。结论不同厂家生产的尼群地平片的溶出度存在较大的差异 ,尼群地平片和软胶囊在溶出度方面整体存在较大差异 ,建议《中华人民共和国药典》规定尼群地平片剂的溶出度检查     

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.

---

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.