紫外分光光度法和高效液相色谱法测定利巴韦林片含量的比较

目的:建立紫外分光光度法测定利巴韦林片的含量.方法:采用紫外分光光度法和高效液相色谱法分别测定利巴韦林片的含量.结果:紫外分光光度法平均回收率为100.9%,RSD=0.57%(n=5);高效液相色谱法平均回收率为99.9%,RSD=0.86%(n=5).结论:紫外分光光度法简便、快速,两种方法测定结果一致(P＞0.05).     

差示分光光度法测定安乃近片的含量

目的:建立测定安乃近片含量的新方法。方法:采用差示分光光度法。以0.1mol.L-1盐酸溶液为介质制备参比液,以0.1mol.L-1氢氧化钠溶液为介质制备样品液,通过在波长283nm处,测定2种溶液的差示吸收值直接测定安乃近的含量,并将结果与其他方法(紫外分光光度法、高效液相色谱法和碘量法)比较。结果:安乃近检测浓度线性范围为10.35～51.75μg.L-(1r=0.9998),平均回收率为99.94%,RSD=0.27%(n=5);4种方法含量测定结果基本一致。结论:建立的新方法测定结果准确,方法简便、专属性强,可用于该制剂的含量测定。     

紫外分光光度法测定安乃近片的含量

目的:寻找准确而简便地测定安乃近片含量的方法。方法:根据安乃近的0.01mol/L HCl溶液在257nm波长处有最大吸收的特点,采用紫外分光光度法。结果:浓度在15～25μg/ml范围内呈良好的线性关系,得回归方程c=38.11A-0.478,r=0.9999。平均回收率为99.2％(n=3),与碘量法相比较,无明显差异。结论:实验表明,用紫外分光光度法测定安乃近片的含量,操作简便,结果准确,令人满意。     

安乃近片溶出度测定法的研究

建立安乃近片溶出度测定方法。选用中国药典 2 0 0 0年版溶出度测定法第一法 ,紫外分光光度法检测。结果 :测定波长为 2 5 7nm ,浓度在 10～2 5 μg·ml- 1范围内 ,与吸收度呈良好线性关系 (r =0 9999) ,平均回收率为 10 0 78%、RSD为 0 5 2 (n =4 ) ,每片溶出量应为标示量的 75 %以上。本法适合于安乃近片溶出度测定     

氟康唑壳聚糖滴眼液的制备及疗效观察

目的:研制氟康唑壳聚糖滴眼液.方法:采用紫外分光光度法测定氟康唑的含量.对28例患真菌性角膜炎患者进行疗效观察.结果:采用紫外分光光度法测定含量,其线性范围为25～300μg·ml-1,最低检测浓度为25μg·ml-1,平均回收率99.86%,RSD为0.36%(n=5),r=0.999.经治疗痊愈78.6%,好转17.9%,无效3.5%,总有效率96.4%.结论:该滴眼液疗效确切,紫外分光光度法测定含量方法简便、快速、准确.     

紫外分光光度法测定双苯氟嗪片的含量、含量均匀度及溶出度

目的:建立紫外分光光度法测定双苯氟嗪片含量、含量均匀度及溶出度的方法.方法:采用紫外分光光度法测定含量、含量均匀度和溶出度.溶剂为0.1 mol·L-1的盐酸溶液;测定波长为248 nm;含量及含量均匀度的测定浓度为12.5 μg·mL-1,溶出度的测定浓度为10μg·mL-1.采用对照品比较法计算含量、含量均匀度和溶出度.结果:双苯氟嗪在4～28 μg·mL-1的范围内线性关系良好,r=0.999 9(n=7).平均回收率为99.7%,RSD为0.16%(n=9).结论:该法简便,准确,可作为双苯氟嗪片含量、含量均匀度及溶出度的测定方法.     

紫外分光光度法测定谷胱甘肽片的含量

目的:建立紫外分光光度法测定谷胱甘肽片的含量.方法:紫外分光光度法,检测波长:230nm.结果:平均回收率为100.5%,n=5,RSD为1.18%.结论:方法可靠,操作简便,可用于谷胱甘肽片的质量控制.     

5种中药重金属的检测研究

目的:探讨紫外分光光度法在监测中药重金属含量中的应用.方法:采用紫外分光光度法测定桔梗、丹参、党参、川芎、地龙重金属的含量.结果:对照品重金属的检测浓度在0～5μg·ml-1,质量浓度范围内与吸收度呈良好线性关系(r=0.9993);平均回收率为98.46%,RSD=1.49%(n=6);桔梗、丹参、党参的重金属含量为25.60、27.12、24.44μg·g-1;川芎、地龙的重金属含量偏高,分别为47.38、50.56μg·g-1.结论:紫外分分光光度法可用于检测中药重金属的含量.     

紫外分光光度法测定拉米夫定片的含量

目的探讨用紫外分光光度法测定拉米夫定片的含量。方法以水为空白,检测波长为280nm。结果回归方程为C=15.6608A-0.19628,r=0.9999,拉米夫定质量浓度线性范围是2.5～20.0μg/mL,平均回收率为99.92%,RSD=0.37%(n=5)。结论紫外分光光度法简便快速,重现性好,适用于拉米夫定片的含量测定。     

紫外分光光度法测定瑞巴派特片中瑞巴派特的含量

目的:建立紫外分光光度法测定瑞巴派特片含量的方法。方法:以pH=6.8的磷酸盐缓冲液为溶剂,在(326±2)nm波长处测定含量。结果:瑞巴派特浓度在9.8～49.2μg/mL范围内与吸收度呈良好的线性关系,相关系数r=0.9999,平均回收率为99.8%RSD=0.4%(n=5)。结论:紫外分光光度法操作快速、简便,结果准确,适合于该制剂的含量测定。     

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.     

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.     

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.     

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.