盐酸伐昔洛韦片的人体生物等效性

目的研究2种盐酸伐昔洛韦片的生物等效性。方法18名健康受试者单剂量交叉口服500和600 mg 2种规格的盐酸伐昔洛韦片,采用HPLC-UV检测法测定血药浓度。数据经DAS软件处理。结果盐酸伐昔洛韦供试制剂600 mg片与参比制剂500 mg片的主要药动学参数如下:AUC0→Tn分别是(11.15±2.05)、(9.82±2.09)mg.h.L-1;AUC0→∞分别为(11.80±2.24)、(10.51±2.20)mg.h.L-1;ρmax分别是(2.85±0.62)、(2.40±0.51)mg.L-1;tmax分别是(2.19±0.30)、(2.19±0.25)h;t21分别是(2.51±0.45)、(2.80±0.35)h。将两制剂主要药动学参数AUC0→Tn、AUC0→∞、ρmax经剂量校正后对数转化,作生物等效性分析,按AUC0→Tn计算,受试片的相对生物利用度为(94.30±8.62)%。tmax经非参数秩和检验,两制剂差异无统计学意义。结论2种规格的盐酸伐昔洛韦生物等效。     

人血浆中阿昔洛韦的HPLC-MS法的建立及盐酸伐昔洛韦片的生物等效性研究

目的:建立人血浆中盐酸伐昔洛韦在人体内代谢产物阿昔洛韦的HPLC-MS分析方法,分析临床用药每人0.3 g盐酸伐昔洛韦片时,阿昔洛韦在人体内的药动学过程和特征,评价受试制剂和参比制剂的生物等效性.方法:采用双交叉随机实验设计:20名健康男性受试者随机交叉口服两种盐酸伐昔洛韦片0.3 g后,采用HPLC-MS法测定人血浆中阿昔洛韦浓度,计算药代动力学参数.结果:20名健康男性受试者口服受试制剂和参比制剂0.3 g后,估算的阿昔洛韦的消除半衰期分别为3.07±0.31 h和3.05±0.25 h,达峰时间分别为0.9±0.2 h和1.0±0.2 h,达峰浓度分别为2054.8±757.8 ng·mL-1和2137.0±563.2 ng·mL-1,AUC0-15分别为5899.3±1757.3μg·mL-1和6032.4±1702.3μg·h·L-1.用面积法(AUC0-15)估算的受试制剂的相对生物利用度为98.9%±16.6%.结论:本试验建立的测定方法灵敏、准确、简便.新制剂盐酸伐昔洛韦片和市售盐酸伐昔洛韦片的药代动力学参数相近,统计学结果表明:两种盐酸伐昔洛韦片生物等效.     

盐酸伐昔洛韦片的人体药动学及生物等效性

目的研究盐酸伐昔洛韦片在健康人体内的药动学及相对生物利用度。方法采用双周期交叉试验设计,利用建立的高效液相色谱法测定了20名健康男性受试者口服盐酸伐昔洛韦片后不同时间血浆中伐昔洛韦的活性代谢物阿昔洛韦的浓度,同时绘制血浆药物浓度-时间曲线并计算出主要药动学参数。结果20名受试者分别口服含盐酸伐昔洛韦片300 mg的受试制剂和参比制剂后,血浆中伐昔洛韦的活性代谢物阿昔洛韦的tm ax分别为(0.90±0.35)和(0.98±0.36)h,mρax分别为(2.55±0.64)和(2.49±0.61)mg.L-1,t1/2分别为(2.00±0.33)和(1.94±0.22)h;用梯形法计算,AUC0-14分别为(5.80±0.89)和(6.05±1.04)mg.h.L-1,AUC0-∞分别为(6.16±0.95)和(6.35±0.98)mg.h.L-1;以AUC0-14计算,盐酸伐昔洛韦片的相对生物利用度平均为(96.9±12.4)%。结论盐酸伐昔洛韦片2种制剂具有生物等效性。     

盐酸伐昔洛韦泡腾片在人体内的生物等效性

目的考察两种盐酸伐昔洛韦片的人体生物等效性。方法采用双制剂双周期自身交叉对照的方法,将18名健康男性受试者随机分为两组,单剂量口服盐酸伐昔洛韦受试制剂和参比制剂各0.6 g;血浆中阿昔洛韦浓度用HPLC法测定,DAS软件计算药物动力学参数,并对其进行生物等效性评价。结果盐酸伐昔洛韦受试制剂和参比制剂的Cm ax分别为2.54±0.32、2.59±0.44μg.m l-1;Tm ax分别为2.28±0.31、2.22±0.26 h;AUC0→Tn分别为10.75±1.804、11.35±2.548μg.h.m l-1,AUC0→∞分别为11.49±2.06、12.09±2.757μg.h.m l-1;t1/2分别为2.55±0.69 h、2.67±0.76 h。按盐酸伐昔洛韦药-时曲线下0→Tn的面积计算,相对生物利用度为96.1%。结论盐酸伐昔洛韦受试制剂与参比制剂相比,AUC、Cm ax符合生物等效性要求,Tm ax比较差异无统计学意义,受试制剂和参比制剂具有生物等效性。     

单次口服盐酸伐昔洛韦缓释片在健康人体的药代动力学

目的研究盐酸伐昔洛韦缓释片(抗病毒药)在健康人体内的药代动力学特征。方法12名健康志愿者按拉丁方设计分别口服3种单剂量(600,1200,1800mg)盐酸伐昔洛韦缓释片,用高效液相色谱-紫外检测法测定血浆中盐酸伐昔洛韦活性代谢物阿昔洛韦浓度,用DAS1.0软件计算药代动力学参数。结果12名受试者血药浓度随其单次给药剂量的增加而呈现升高趋势,口服盐酸伐昔洛韦缓释片600,1200,1800mg的AUC0～24分别为(6.61±1.38),(13.38±3.76)和(20.62±8.20)mg.h.L-1;Cmax分别为(1.67±0.37),(3.10±0.87)和(4.73±2.15)mg.L-1,不同剂量组的AUC0-24/dose、Cmax/Dose比值间无显著性差异。结论在600～1800mg内,盐酸伐昔洛韦缓释片在健康人体内过程呈线性药代动力学特征。     

盐酸伐昔洛韦在健康志愿者体内的生物等效性

目的:评价国产盐酸伐昔洛韦片在20名男性健康志愿者体内的生物等效性。方法:采用高效液相色谱荧光检测法测定20名健康志愿者单剂量、交叉口服盐酸伐昔洛韦片300 mg后血浆中阿昔洛韦浓度。用DAS软件进行药动学参数计算及生物等效性评价。结果:试验制剂或参比制剂C_max分别为(1．919±0．416)μg·ml-1和(1．805±0．566)μg·ml-1,t1/2分别为(3．263±0．564)h和(3．067±0．476)h,tmax分别为(1．175±0．373)h和(1．275±0.499)h,AUC0→t,AUC0→∞平均值分别为(6.504±1．369)μg·ml-1·h和(6．176±1．504)μg·ml-1·h,相对生物利用度F0-tn％、F0-∞％分别为(99．568±29．316)％、(107．292±17．844)％。结论:两种盐酸伐昔洛韦片剂具有生物等效性。     

盐酸伐昔洛韦缓释片家犬药动学研究

目的:研究盐酸伐昔洛韦缓释片(HVSRT)与盐酸伐昔洛韦片(HVT)在家犬体内药动学,为人体生物利用度研究提供依据和参考.方法:以市售HVT为参比制剂,采用反相高效液相色谱法测定血浆中阿昔洛韦浓度,按单剂量、多剂量给药方案研究并计算药动学参数.结果:HVRST与HVT单剂量给药后,血浆中阿昔洛韦的Tmax分别为(3.5±1.1)和(2.3±1.4)h,Cmax分别为(3.81±1.46)和(4.24±1.51)μg·mL-1,MRT分别为(5.4±1.6)和(4.6±0.8)h,AUC0～τ分别为(25.53±8.96)和(26.22±8.92)μg·h·mL-1,AUC0～∞分别为(29.42±7.15)和(29.41±1.89)μg·h·mL-1,HVSRT相对生物利用度F(0-Tn)为(97.02±12.54)%.HVRST和HVT多剂量给药达稳态后,血浆中阿昔洛韦的Cmax分别为(4.51±0.91)和(7.07±2.36)μg·mL-1,Cmin分别为(1.20±0.32)和(0.58±0.15)μg·mL-1,FI分别为(135.2±14.3)%和(481.3±101.3)%.结论:HVSRT与HVT生物等效,且HVRST具有明显的缓释特征,能持久地维持比HVT更平稳的血药浓度.     

安吡昔康胶囊的人体生物等效性

目的:进行试验制剂安吡昔康胶囊与参比制剂安吡昔康片的单剂双交叉人体生物等效性考察。方法:采用高效液相色谱法测定安吡昔康代谢物吡罗昔康血浓度,以DAS软件计算吡罗昔康主要药动学参数,评价两制剂的生物等效性。结果:安吡昔康试验制剂和参比制剂活性代谢物吡罗昔康主要药动学参数t1/2分别为(44.7±9.0)h和(46.2±13.0)h,Tmax分别为(7.7±2.2)h和(7.2±1.6)h,Cmax分别为(2.6±0.5)mg.L-1和(2.6±0.5)mg.L-1,AUC0~144分别为(187.3±32.1)mg.L-1.h和(188.7±30.0)mg.L-1.h,AUC0-∞分别为(216.6±36.6)mg.L-1.h和(219.1±40.2)mg.L-1.h。试验制剂人体相对生物利用度(100.2±15.9)%。结论:安吡昔康试验制剂和参比制剂中吡罗昔康主要药动学参数周期间和剂型间无显著性差异,为生物等效制剂。     

盐酸伐昔洛韦片的人体药动学及生物等效性研究

目的:研究单剂量口服盐酸伐昔洛韦片的药动学特征,并评价2种制剂的生物等效性。方法:采用双周期交叉试验方法,18名健康志愿者分别单剂量口服2种盐酸伐昔洛韦片600mg,采用高效液相色谱法测定血浆中药物浓度,计算药动学参数,并进行统计分析。结果:盐酸伐昔洛韦片受试制剂与参比制剂的主要药动学参数tmax分别为(1.69±0.25)、(1.72±0.26)h,Cmax分别为(3.34±0.58)、(3.40±0.49)μg·mL-1,t1/2分别为(2.73±0.31)、(2.97±0.33)h,AUC0～14分别为(11.22±2.21)、(11.12±1.90)μg·h·mL-1,AUC0～∞分别为(11.76±2.15)、(11.61±1.86)μg·h·mL-1。受试制剂相对于参比制剂的生物利用度为(101.06±11.72)%。结论:2种制剂具有生物等效性。     

盐酸伐昔洛韦片人体生物等效性研究

目的研究盐酸伐昔洛韦片在健康人体内的生物等效性。方法20名受试者单剂量、交叉口服盐酸伐昔洛韦片受试制剂和参比制剂后,采用高效液相色谱-荧光检测法测定其体内代谢转化物阿昔洛韦的血药浓度,以BAPP2.0程序计算药动学参数和生物等效性数据。结果受试制剂和参比制剂的阿昔洛韦,其Cmax分别为(2.04±0.48)、(1.94±0.37)μg·mL-1,tmax分别为(1.3±0.6)、(1.4±0.6)h,t1/2分别为(2.53±0.42)、(2.55±0.43)h,AUC0～12分别为(5.82±0.99)、(5.54±0.84)μg·h·mL-1,AUC0～∞分别为(6.04±1.04)、(5.76±0.94)μg·h·mL-1。经方差分析和配对t检验,受试制剂与参比制剂的药动学参数无显著性差异(P>0.05),受试制剂的相对生物利用度为(105.7±13.9)%。结论2种制剂具有生物等效性。     

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.