LC-MS/MS法测定坦索罗辛在比格犬血浆中的浓度及其缓释制剂的药动学研究

目的:建立坦索罗辛血药浓度LC-MS/MS测定方法,并研究坦索罗辛缓释制剂在比格犬体内的药代动力学。方法:6只比格犬空腹单次口服给予含有0.4 mg的盐酸坦索罗辛缓释胶囊,给药前(0 h)、给药后不同时间点各采血0.3 mL,分离血浆后,加入内标愈创木酚甘油醚,经乙酸乙酯萃取,以甲醇:水:甲酸(80∶20∶0.2,V/V/V)为流动相,在反相C18色谱柱进行分离。采用电喷雾离子源(ESI源)的正离子方式检测,扫描方式为选择反应监测(SRM),用于定量分析的离子反应为m/z409.0→m/z228.0(坦索罗辛)和m/z199.0→m/z125.0(内标,愈创木酚甘油醚)。结果:坦索罗辛在线性范围内0.05～10.0 ng/mL线性良好,定量下限为0.05 ng/mL,批内、批间精密度(RSD)均小于13.4%。盐酸坦索罗辛缓释制剂0.4 mg口服给药后AUC0-24 h为(7.82±1.92)ng.h.mL-1、AUC0-∞为(8.04±2.02)ng.h.mL-1t、1/2为(2.96±2.13)h。结论:LC-MS/MS法灵敏度高、分析快速,适用于比格犬血浆中坦索罗辛的药动学研究,坦索罗辛缓释胶囊口服给药后半衰期短,消除快。     

盐酸美金刚缓释胶囊在中国健康受试者的生物等效性研究

目的 研究空腹及餐后状态下口服两种不同厂家生产的盐酸美金刚缓释胶囊在中国健康受试者体内的生物等效性。方法 本研究采用单中心、随机、开放、两周期、双交叉、单次给药的试验设计，空腹组和餐后组各入组28例健康受试者，每周期单次空腹/餐后口服盐酸美金刚缓释胶囊受试制剂或参比制剂28 mg,采用经过验证的LC-MS/MS法测定血浆中美金刚的血药浓度，计算药代动力学参数，进行两种盐酸美金刚缓释胶囊的人体生物等效性及安全性评价。结果 空腹组受试制剂和参比制剂的t_1/2分别为(66.99±13.32)和(66.79±10.43)h,t_max中位数分别为28.00(14,40)h和30.00(14,40)h,C_max分别为(31.42±4.47)和(30.69±4.26)ng·mL^-1,AUC_0-t分别为(3 592.17±578.74)和(3 533.52±516.64)h·ng·mL^-1,AUC_0-∞分别为(3 776.91±674.44)和(3 ...     

不同处方头孢克肟胶囊在比格犬体内的药动学

目的 研究两种不同处方头孢克肟胶囊受试制剂与参比制剂在比格犬体内的生物等效性。方法 8只比格犬采用3周期给药方法,单次灌胃50mg头孢克肟胶囊受试制剂或参比制剂,LC-MS/MS法测定比格犬体内头孢克肟血药浓度,计算药动学参数并进行生物等效性评价。结果 单次灌胃自制制剂和参比制剂后,参比制剂、受试制剂A和B的主要药动学参数Cmax分别为(11.24±26.39)、(14.33±8.29)和(10.24±5.36)ng/mL,Tmax分别为(2.69±1.31)、(3.52±1.58)和(2.75±1.76)h,AUC0-48h分别为(0.11±0.19)、(0.14±0.06)和(0.11±0.32)ng·h/mL,AUC0-∞分别为(0.13±0.20)、(0.16±0.09)和(0.12±0.04)ng·h/mL。结论     

不同处方头孢克肟胶囊在比格犬体内的药动学

目的 研究两种不同处方头孢克肟胶囊受试制剂与参比制剂在比格犬体内的生物等效性。方法 8只比格犬采用3周期给药方法,单次灌胃50mg头孢克肟胶囊受试制剂或参比制剂,LC-MS/MS法测定比格犬体内头孢克肟血药浓度,计算药动学参数并进行生物等效性评价。结果 单次灌胃自制制剂和参比制剂后,参比制剂、受试制剂A和B的主要药动学参数Cmax分别为(11.24±26.39)、(14.33±8.29)和(10.24±5.36)ng/mL,Tmax分别为(2.69±1.31)、(3.52±1.58)和(2.75±1.76)h,AUC0-48h分别为(0.11±0.19)、(0.14±0.06)和(0.11±0.32)ng·h/mL,AUC0-∞分别为(0.13±0.20)、(0.16±0.09)和(0.12±0.04)ng·h/mL。结论 受试制剂A与参比制剂生物不等效,受试制剂B与参比制剂生物等效,两种受试制剂生物不等效。     

盐酸氨溴索缓释混悬剂在犬体内的生物等效性研究

目的:研究盐酸氨溴索缓释混悬剂在犬体内的药动学特征,进行生物等效性评价。方法:以市售盐酸氨溴索缓释胶囊为参比制剂,采用双周期试验设计,选用6只Beagle犬分别灌服参比制剂或受试制剂(盐酸氨溴索缓释混悬剂)75 mg,给药后1、2、3、4、5、6、8、10、12、14、24 h取前肢静脉血5 ml,采用高效液相色谱法测定盐酸氨溴索的血药浓度,以非隔室模型法计算药动学参数,分析生物等效性。结果:受试制剂和参比制剂的药动学参数t1/2分别为(4.21±0.15)、(4.48±0.22)h,tmax分别为(5.00±0.00)、(4.33±0.52)h,cmax分别为(1.90±0.27)、(2.06±0.18)μg/ml,AUC0-24 h分别为(21.70±3.11)、(20.55±1.38)μg·h/ml,其中cmax和AUC0-24 h90%的可信区间均在88.9%¹13.8%内,受试制剂对参比制剂的相对生物利用度为105.2%。结论:盐酸氨溴索缓释混悬剂具有缓释效果,且与参比制剂生物等效。     

右旋兰索拉唑缓释胶囊在Beagle犬体内的药动学及生物等效性

目的研究右旋兰索拉唑缓释胶囊在Beagle犬体内的药动学特征及生物等效性。方法采用LC-MS/MS法测定10只Beagle犬单次和多次口服右旋兰索拉唑缓释胶囊受试制剂和参比制剂后的血药质量浓度,计算药动学参数。结果单次口服受试制剂和参比制剂后,血浆中右旋兰索拉唑的t1/2分别为(1.2±1.0)和(1.0±0.7)h,tmax分别为(2.3±1.0)和(2.6±1.1)h,ρmax分别为(2.388 6±0.639 1)和(2.348 5±0.728 6)mg·L-1,AUC0-t分别为(5.601 4±1.627 4)和(5.602 3±1.865 7)mg·h·L-1,AUC0-∞分别为(5.653 6±1.630 9)和(5.657 5±1.878 6)mg·h·L-1。以AUC0-t计算,受试制剂中右旋兰索拉唑的相对生物利用度为(101.6±8.9)%。多次口服给药后的主要药动学参数与单次口服基本一致。结论右旋兰索拉唑的药动学参数在Beagle犬体内个体差异较大,右旋兰索拉唑缓释胶囊的两种制剂生物等效。     

右兰索拉唑缓释胶囊在比格犬体内的药动学

目的：研究右兰索拉唑缓释胶囊在比格犬体内的药动学特征。方法：将6只比格犬随机分为2组,采用双周期双交叉给药方法,单次灌胃60 mg右兰索拉唑缓释胶囊受试制剂或参比制剂,LC-MS/MS法测定比格犬体内右兰索拉唑血药浓度,计算药动学参数并进行生物等效性评价。结果：单次灌胃受试制剂和参比制剂后,比格犬血浆中右兰索拉唑的t_1/2分别为（1.34±0.73）和（1.42±0.63） h,T_max分别为（5.7±0.52）和（5.8±1.17） h,C_max分别为（385.5±37.14）和（380.5±53.3） ng·mL^-1,AUC_0-t分别为（1 463.9±213.2）和（1 502.3±147.8） ng·h·mL^-1,AUC_0-∞分别为（1 476.4±215.7）和（1 514.3±149.5） ng·h·mL^-1。结论：右兰索拉唑缓释胶囊受试制剂与参比制剂在比格犬体内生物等效。     

水飞蓟素磷脂复合物微孔渗透泵控释片比格犬体内药动学及体内外相关性研究

目的 评价水飞蓟素磷脂复合物微孔渗透泵(SM-PC MPOP)控释片的体外释药特性、比格犬体内药动学及其体内外相关性。方法 释放介质为pH7.5的磷酸盐缓冲液(添加0.5%十二烷基硫酸钠),以高效液相色谱法(HPLC)检测SM-PC MPOP的体外释放特征。用6只比格犬进行双周期交叉对照实验,按照30 mg/kg的剂量给药。HPLC法测定比格犬血浆内水飞蓟素的主要成分水飞蓟宾的质量浓度,应用药动学软件进行数据分析。结果 SM-PC MPOP在12 h累积释放度超过85%。药动学研究情况表明,受试制剂(SM-PC MPOP)和参比制剂(市售水飞蓟素胶囊)在比格犬体内的主要药动学参数：T_max分别为(3.2±0.4)、(0.9±0.1)h,C_max分别为(0.298 6±0.068 9)、(0.629 9±0.076 5)μg/ml,AUC_0→24分别为(2.996 8±0.583 3)、(2.268 9±0.432 8) h·μg/ml,SM-PC-MPOP对市售水飞蓟素胶囊的相对生物利用度为(162.21±30.82)%...     

头孢氨苄缓释片犬体内药动学研究

目的以上市头孢氨苄普通胶囊为参比制剂,考察24h给药一次的头孢氨苄缓释片beagle犬体内药动学。方法 Beagle犬单剂量口服受试制剂和参比制剂,采用HPLC法进行生物等效性评价。结果方法学研究结果显示线性范围0.5～50μg/mL,高中低相对回收率均大于80%,日内日间精密度均小于15%,最低定量限0.5μg/mL。参比制剂与受试制剂药动学参数分别为:Cmax为(35.02±8.67)和(22.8±74.11)μg/mL,AUC0-∞为(164.59±17.79)和(201.15±89.87)μg/(h·mL),Tmax为(2.1±1.0)和(4.2±0.4)h。受试制剂相对生物利用度为(104.4±21.4)%。结论两种制剂生物等效。     

布洛芬缓释胶囊单剂量与多剂量给药的人体药动学及生物等效性研究

目的:研究布洛芬缓释胶囊单剂量与多剂量给药的人体药动学及生物等效性.方法:分别给予32名健康男性志愿者口服单剂量、多剂量布洛芬缓释胶囊受试制剂以及参比制剂300mg.根据双周期自身随机交叉实验设计,使用高效液相色谱法(HPLC)对血浆中布洛芬浓度进行测定.其中人体药动学参数采用DAS2.0程序进行计算,并对两种制剂生物等效性进行分析.结果:单剂量口服受试制剂以及参比制剂后tmax分别为(5.6±1.3)h、(4.9±1.1)h,Cmax分别为(12.8±5.5)μg/mL、(13.6±5.8)μg/mL,AUC0-24分别为(96.5±49.6)μg·h/mL、(95.9±45.2)μg·h/mL,AUC0-∞分别为(101.5±501.7)μg·h/mL、(101.6±46.8)μg·h/mL.多剂量口服受试制剂以及参比制剂后tss,max分别为(4.9±1.1)h、(4.6±1.0)h,Css,max分别为(14.2±5.5)μg/mL、(14.7±6.3)μg/mL,Css,min分别为(4.0±1.6)μg/mL、(3.8±2.3)μg/mL,Cav分别为(8.3±3.6)μg/mL、(8.5±4.4)μg/mL,AUCss分别为(98.8±39.8)μg·h/mL、(103.2±50.9)μg·h/mL,DF分别为(118.1±35.2)％、(132.1±34.8)％,差异均无统计学意义(均P＞0.05).经由双单侧t检验以及90％置信区间分析,根据参比制剂为标准,分别给药后,试验制剂的90％置信区间在可信区间内.结论:布洛芬缓释胶囊单剂量与多剂量给药中受试制剂与参比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.     

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.     

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.