比浊法测定阿奇霉素效价的研究

目的:建立测定阿奇霉素效价的方法。方法:采用比浊法测定阿奇霉素的效价,并与管碟法比较。结果:阿奇霉素检测浓度的线性范围为0.4～2.0I U.mL-1(r=0.999 1) ;回收率为99.70%～100.02%(RSD为0.22%～0.46%) ;比浊法与管碟法的测定结果无显著性差异。结论:本方法操作更快捷、方便。     

浊度法测定阿奇霉素的效价

目的建立浊度法测定阿奇霉素效价的方法。方法金黄色葡萄球菌为实验菌,加菌量1.5%~2.0%(V/V),培养温度35℃~37℃,培养时间4~6h测定。结果阿奇霉素线性浓度1.42u·mL-1~5.67u·mL-1,(R=0.99)。二剂量法的平均回收率103.4%(n=6),RSD为1.7%。结论本方法灵敏,快速、可作为测定阿奇霉素效价的方法。     

微生物浊度法与管碟法测定乙酰麦迪霉素制剂的效价

目的:建立浊度法测定乙酰麦迪霉素制剂(片剂与干混悬剂)效价的方法,并与管碟法进行比较。方法:浊度法以金黄色葡萄球菌为试验菌,加菌量为1.2%,(37±0.5)℃培养3～4h后于抗生素比浊法测量仪530nm波长处测定吸光度,与管碟法比较片剂与干混悬剂样品效价结果。结果:浊度法乙酰麦迪霉素检测浓度线性范围为0.3～3.0u.mL-(1r=0.9983);片剂和干混悬剂样品的平均回收率分别为101.99%(RSD=1.94%,n=9)、101.68%(RSD=1.68%,n=9);2种测定方法效价比较无显著性差异(t=1.473<4.303)。结论:与管碟法比较,本文建立的浊度法准确、可靠、快捷,检测限更低,影响因素较少,与管碟法均可作为测定乙酰麦迪霉素制剂效价的方法。     

微生物比浊法测定口服阿奇霉素的效价含量

目的 建立以微生物比浊法测定口服阿奇霉素效价含量的方法.方法 采用比浊法测定阿奇霉素的含量,并对微生物比浊法、管碟法测定阿奇霉素效价的结果进行评价.结果 阿奇霉素的线性范围为0.4～1.32 u·mL-1(r=0.995 9),分散片与颗粒的平均回收率分别为100.11%,100.27%,方法重复性良好(RSD为0.4%),比浊法与管碟法测定结果一致.结论 微生物比浊法具有简便、精确、快速的特点,可以应用于该产品的质量控制.     

浊度法测定吉他霉素片与乙酰吉他霉素干混悬剂中主药的效价

目的:建立测定吉他霉素片及乙酰吉他霉素干混悬剂中主药效价的浊度法。方法:以金黄色葡萄球菌为试验菌,吉他霉素加菌量1.0%～1.5%、乙酰吉他霉素加菌量2.0%～2.5%,于(37±0.5)℃培养4～5h后在530nm波长下测定吸光度。结果:吉他霉素、乙酰吉他霉素检测浓度线性范围分别为0.5～4.0、0.45～6.3IU.mL-1,回收率分别为101.7%、101.1%(RSD=1.9%、2.1%,n=9)。结论:所建立的浊度法灵敏、快速、影响因素较少,可用于测定吉他霉素片和乙酰吉他霉素干混悬剂中主药的效价。     

比浊法自动测定可利霉素片的效价

目的:建立比浊法测定可利霉素片效价的方法。方法:以金黄色葡萄球菌为试验菌,加菌量为0.5%(V/V),温度为(37±0.5)℃,培养时间3.5～4.0h测定。结果:抗生素线性最佳浓度范围为6.4～15.7 u.mL-1,平均回收率为100.7%(n=9),RSD=1.7%。结论:本方法灵敏、快速、实用,可作为测定可利霉素片效价的方法。     

浊度法测定12-去羟基阿奇霉素的效价

目的建立浊度法测定12-去羟基阿奇霉素效价的方法。方法以肺炎克雷伯菌为试验菌,加菌量0.6%-1.0%（V/V）,37℃±0.5℃培养4h左右测定。结果抗生素线性浓度为2.0-10.0U/ml,二剂量法原料的平均回收率为101.2%,RSD为2.2%（n=9）。结论本方法灵敏,快速,影响因素较少,可作为测定12-去羟基阿奇霉素的效价的方法。     

阿奇霉素胶囊的人体生物等效性研究

目的:研究2种阿奇霉素胶囊在健康人体内的药动学,并评价其生物等效性。方法:采用随机、双交叉自身对照试验设计,19名健康受试者单剂量口服阿奇霉素胶囊受试制剂与参比制剂500mg,服药后0～144h间隔取血,用液-质联用法测定阿奇霉素在血浆中的浓度,采用DAS2.0.1药动学软件计算药动学参数并进行生物等效性评价。结果:参比制剂与受试制剂的tmax分别为(2.658±0.914)、(2.816±1.193)h,Cmax分别为(248.579±89.395)、(236.737±62.668)ng·mL-1,AUC0～144分别为(3121.862±750.631)、(3006.864±784.840)ng.h.mL-1,AUC0～∞分别为(3446.478±834.751)、(3484.274±968.909)ng.h.mL-1。受试制剂的相对生物利用度为(99.2±26.7)%。结论:2种制剂生物等效。     

阿奇霉素干混悬剂的人体药动学及生物等效性研究

目的:评价2种阿奇霉素干混悬剂的生物等效性。方法:20名男性健康志愿者随机交叉口服受试制剂或参比制剂10袋(含阿奇霉素1.0g)后,采用反相高效液相色谱法测定血浆中的药物浓度,并计算有关药动学参数,通过方差分析和双单侧t检验和1～2α置信区间法进行生物等效性评价。结果:受试制剂与参比制剂中阿奇霉素的Cmax分别为(29.651±5.600)、(29.256±6.382)μg·mL-1,tmax分别为(2.25±0.444)、(2.400±0.503)h,t1/2分别为(37.910±10.181)、(37.980±9.220)h,AUC0～120分别为(458.139±47.368)、(463.114±42.267)μg.h.mL-1,AUC0～∞分别为(519.217±57.262)、(522.980±48.267)μg.h.mL-1。受试制剂相对于参比制剂的生物利用度为(99.5±8.9)%。结论:2种制剂生物等效。     

阿奇霉素凝胶的制备及质量控制

目的:制备阿奇霉素凝胶并建立质量标准.方法:研制阿奇霉素凝胶,采用硫酸呈色分光光度法测定制剂中阿奇霉素的含量.结果:阿奇霉素凝胶的平均回收率为(98.77±0.93)%.结论:该制剂制备工艺简单,性质稳定,质量可靠.     

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.