洛伐他汀缓释片在Beagle犬体内的药动学特性与生物等效性

目的:研究洛伐他汀缓释片在Beagle犬体内的药动学特征及其口服相对生物利用度。方法:Beagle 犬12条随机分为2组,分别单次口服洛伐他汀缓释片和普通片备60 mg,用RP-HPLC法检测血药浓度。药动学参数用3P97软件分析。结果:洛伐他汀缓释片和普通片的tmax分别为(2．7±5 0．8)和(2．8±1．0)h,cmax分别为(137±43)和(176±59)μg·L-1,t1／2分别为(11±4)和(10±5)h;AUC0-(?)分别为(956±146)和(1 005± 147)μg·h·L-1。以AUC0-(?)计算,与普通片相比,洛伐他汀缓释片的相对生物利用度为(95±6)％。洛伐他汀缓释片和普通片AUC0-(?)对数比值的90％可信限为81．6％-112．2％。结论:洛伐他汀缓释片具有一定缓释特性,与普通片相比具有生物等效性。     

氯氮平缓释片在小猎兔犬体内的药动学特性与生物等效性

目的:研究氯氮平缓释片在小猎兔犬(Beagle犬)体内的药动学特征及其口服相对生物利用度。方法:6条Beagle犬随机分成2组,采用自身对照交叉实验设计,分别单次口服氯氮平缓释片和普通片各100mg,用RP-HPLC法检测血药浓度。药动学参数用统计矩法计算。结果:氯氮平缓释片和普通片的tmax分别为(7.3±s 1.0)和(3.3±0.8)h;Cmax分别为(986±274)和(1388±346)μg·L~(-1),t_(1/2)分别为(8.1±1.4)和(9.5±1.0)h;AUC_(0-t)分别为(17452±5618)和(14174±3420)μg·h·L~(-1)。以AUC_(0-t)计算,与普通片相比,氯氮平缓释片的相对生物利用度为(120±28)％。2种制剂的主要药动学参数经统计学检验,两者差异有显著意义(P<0.05)。结论:氯氮平缓释片具有一定缓释特性,生物利用度优于普通制剂。     

复方烟酸缓释片与烟酸普通片在犬体内药代动力学的比较研究

目的比较复方烟酸缓释片与烟酸普通片中烟酸及其代谢物烟尿酸在Beagle犬体内的药代动力学。方法6只Beagle犬采用随机交叉给药方案,单剂量口服500mg复方烟酸缓释片或烟酸普通片后,用RP-HPLC法同时测定Beagle犬血浆中烟酸及其主要代谢物烟尿酸的药物浓度,计算药动学参数和相对生物利用度。结果Beagle犬单剂量口服500mg复方烟酸缓释片和烟酸普通片后,烟酸主要药代动力学参数tmax分别为(2.17±0.61)h和(1.04±0.49)h,Cmax分别为(30.85±4.50)mg·mL-1和(68.05±20.48)mg·mL-1,t1/2分别为(0.69±0.43)h和(0.43±0.10)h,MRT分别为(2.12±0.62)h和(1.72±0.40)h,AUC0-12h分别为(62.17±21.13)mg·h·L-1和(138.67±44.86)mg·h·L-1;烟尿酸主要药代动力学参数tmax分别为(2.42±0.49)h和(1.50±0.45)h,Cmax分别为(0.76±0.34)mg·mL-1和(1.66±0.63)mg·mL-1,t1/2分别为(1.74±1.24)h和(1.64±1.03)h,MRT分别为(2.42±0.62)h和(1.79±0.38)h,AUC0-12h分别为(1.55±0.76)mg·h·L-1和(3.25±1.16)mg·h·L-1。结论单剂量口服复方烟酸缓释片,测得的Cmax、tmax和AUC与烟酸普通片均有显著性差异,受试缓释片的tmax长于参比普通片,Cmax低于参比普通片,说明受试缓释片无突释现象,有一定缓释效果。     

二甲双胍缓释片人体药代动力学及其相对生物利用度

目的研究国产盐酸二甲双胍缓释片在人体药代动力学行为并与普通片进行等效性评价比较,并估算其药代动力学参数。方法20名受试者分两组交叉服用缓释片和普通片,用RPHPLC法测定血浆中药物浓度,并估算相应的药动学参数。结果单剂量口服1000mg缓释片和普通片后估算的AUC0-24分别为11.95±2.62μg·h-1·ml-1和10.72±2.23μg·h-1·ml-1;Cmax分别为1.50±0.22μg·ml-1和2.34±0.30μg·ml-1;Tmax分别为3.38±0.8h和1.61±0.32h;t1/2分别为4.94±0.47h和3.20±0.38h;多剂量1000mg·d-1时AUCss分别为15.04±3.01μg·h-1·ml-1和14.51±2.69μg·h-1·ml-1;Cmax分别为1.68±0.25μg·ml-1和1.60±0.26μg·ml-1;Cmin分别为0.15±0.03μg·ml-1和0.12±0.04μg·ml-1;Cav分别为0.62±0.13μg·ml-1和0.61±0.11μg·ml-1;Tmax分别为3.61±0.60h和1.88±0.38h;AUC0-24和AUCss经对数转换后方差分析和双单侧t检验,显示两制剂吸收程度生物等效。结论受试制剂和参比制剂吸收程度生物等效,但具有缓释特性。盐酸二甲双胍缓释片的相对生物利用度单剂量时为(111.5±8.3)%,多剂量时为(103.6±9.2)%。     

家犬口服单剂量与多剂量阿昔洛韦缓释胶囊的药物动力学研究

目的　研究健康家犬口服单剂量与多剂量阿昔洛韦缓释胶囊的药物动力学。方法　采用HPLC测定口服药物后的血药浓度 ,计算药动学参数。结果　单剂量时阿昔洛韦缓释胶囊的Tmax、Cmax、AUC0 -τ和AUC0 -∞ 分别为 4.6 7± 0 .41h、1.2 0± 0 .14μg.ml-1、11.34± 1.38μg·h·ml-1和 13.5 8± 2 .0 2 μg·h·ml-1.普通片的上述参数分别为3.5 0± 0 .78h、2 .19± 0 .19μg .ml-1、12 .76± 1.0 1μg·h·ml-1和 13.0 1± 1.16 μg·h·ml-1。多剂量达稳态时阿昔洛韦缓释胶囊的Cmax、Cmin、AUC0 -τ、AUC0 -∞ 、峰谷比 (R)和波动系数 (DF)分别为 1.42± 0 .6 3μg·ml-1、0 .93± 0 .3 6 μg·ml-1、12 .76± 1.0 1μg·h·ml-1、13.0 1± 1.16 μg·h·ml-1、1.5 2± 0 .15和 46 .6 1%± 2 9.34 %;普通片的上述参数分别为(1.72± 0 .2 2 ) μg .ml-1、0 .44± 0 .18μg·ml-1、4.0 0± 0 .46 μg·h·ml-1、4.43± 0 .2 9μg·h·ml-1、4.6 4± 2 .2 8和 12 9.6 9%± 31.2 4%。结论　阿昔洛韦缓释胶囊在健康家犬体内具有明显的缓释作用 ,多剂量达稳态后 ,血药浓度的波动系数显著低于普通片剂。     

盐酸伪麻黄碱缓释片的人体药动学及生物等效性

目的研究盐酸伪麻黄碱(d-peseudoephedrine hydrochloride)缓释片与普通片在正常人体内的药动学和相对生物利用度.方法高效液相色谱法测定20名男性健康志愿者交叉po 60 mg普通片和缓释片后的血药浓度,求算药动学参数并进行统计学评价.结果单剂量po普通片和缓释片主要药动学参数Cmax分别为(317.9±99.6)μg·L-1和(205.1±29.8)μg·L-1;t1/2(Ke)分别为(3.9±0.5)h和(5.7±1.2)h;AUC0～24分别为(2 386.8±246.1)h·μg·L-1和(2 310.9±171.9)h·μg·L-1,相对生物利用度为(97.4±8.8)%.多剂量po普通片和缓释片Cmin分别为(126.6±18.2)μg·L-1和(147.9±18.2)μg·L-1;Cmax分别为(307.9±24.1)μg·L-1和(275.2±26.8)μg·L-1;FI分别为(0.79±0.22)和(0.58±0.14).结论两种制剂生物等效.     

褪黑素缓释片与普通片在犬体内药动学研究

目的:比较褪黑素普通片与缓释片在Beagle犬体内药动学参数。方法:6只Beagle犬随机、交叉、单剂量灌服褪黑素缓释片6mg或普通片3mg后,采用高效液相色谱法测定其血药浓度;以3p97软件计算药动学参数。结果:普通片和缓释片犬体内药-时曲线符合二室模型,Cmax分别为(11.27±3.77)、(8.31±5.11)ng/ml,tmax分别为(0.50±0.18)h、(1.00±0.37)h,t1/2ke分别为(1.21±0.52)h、(3.27±0.89)h,AUC0～t分别为(25.23±7.71)、(38.03±16.45)(ng·h)/ml。结论:与普通片比较,缓释片吸收较慢,药物达峰时间更长,峰浓度更低,消除更慢,维持时间更长。     

舒马普坦胶囊和片剂人体药物动力学及相对生物利用度研究

目的 研究国产舒马普坦胶囊、片剂在人体内的药物动力学及相对生物利用度。方法 采用随机、开放、3×3拉丁方设计,18名男性健康受试者分别单剂量口服试验制剂或参比制剂100 mg。采用HPLC-MS法测定给药后不同时间的血药浓度,采用双单侧t检验进行生物等效性判断。结果 进口参比制剂中舒马普坦的主要药物动力学参数Cmax为(41.68±18.38)μg·L-1;tmax为(2.08±0.65)h;AUC0→12为(152.14±61.63)μg·h·L-1;t1/2为(2.7±0.8)h。国产舒马普坦胶囊的主要药物动力学参数Cmax为(38.01±17.01)μg·L-1;tmax为(1.83±0.45)h;AUC0→12为(136.68±60.71)μg·h·L-1;t1/2为(2.7±1.0)h。国产舒马普坦片剂的主要药物动力学参数Cmax为(38.78±17.67)μg·L-1;tmax为(1.83±0.45)h;AUC0→12为(136.68±60.71)μg·h·L-1;t1/2为(2.7±1.0)h。国产胶囊剂和国产片剂对进口片剂的相对生物利用度分别为91.0％±14.8％和92.0％±11.6％。结论 经统计学分析,国产舒马普坦片剂和胶囊剂与进口制剂具有生物等效性,制剂间药物动力学参数无显著差异。     

单剂量口服硝苯地平缓释片的药动学及生物等效性

目的研究单剂量口服硝苯地平缓释片在人体内的药动学特点和国产硝苯地平缓释片的生物等效性.方法22名健康男性志愿者采用双周期交叉、自身对照试验设计.以尼群地平为内标,采用高效液相色谱-大气压化学源-质谱联用(HPLC-MS)的方法,测定人血浆中硝苯地平的浓度.结果单剂量口服20mg受试和参比制剂后血浆中硝苯地平的Cmax分别为(52.9±31.5)ug·L-1和(52.1±35.6)μg·L-1,Tmax分别为(4.1±1.2)h和(4.7±1.9)h,t1/2分别为(6.9±3.5)h和(7.7±4.5)h,AUC0-36 h分别为(410.7±188.1)μg·h·L-1和(440.4±271.7)μg·h·L-1,AUC0-∞分别为(437.6±206.8)μg·h·L-1和(477.9±290.4)μg·h·L-1.将22名受试者的经时血药浓度录入DAS(ver 1.0)程序,Tmax进行非参数秩和检验,Cmax、AUC0-36h、AUC0-∞、t1/2经对数转换后做方差分析,并经双向单侧t检验,两制剂的tmax、Cmax、AUC0-36h、AUC0-∞、t1/2差异均无显著性,两种制剂的相对生物利用度为(104.4±40.1%)(AUC0-36h.T/AUC0-36h.R×100%).结论两种制剂具有生物等效性.     

异福片的药物动力学与相对生物利用度

目的　研究两种异福片的药物动力学 ,并评价两者的生物等效性。方法　采用RP -HPLC测定 2 4名志愿受试者单剂量po异福片供试品与参比品后利福平和异烟肼血药浓度的变化 ,用 3p97药动学程序拟合药动学参数。结果　两种制剂中利福平AUC0→t分别是 16 3 6 6± 11.33μg·h·ml-1与 172 5 9± 76 .31μg·h ml-1,Tmax分别为 1.92± 0 .19h与 1.96± 0 .4 5h ,Cmax分别是 2 6 .4 2± 11.97μg·ml-1与 2 6 .18± 11.5 7μg·ml-1。两种制剂中异烟肼AUC0→t分别是 4 4 .2 6± 18.84 μg·h·ml-1与 4 6 .18± 16 .6 0μg·h·ml-1,Tmax分别为 1.83± 0 .33h和 1.88± 0 .31h ,Cmax分别是 7.73± 3.2 2 μg·ml-1与 7.76± 3.0 0 μg·ml-1。经剂量校正 ,两种制剂中两组份的lnAUC0→∞ 、lnAUC0→t、Cmax经方差分析均无显著性差异 (P >0 .0 5 ) ;Tmax用双单侧t检验进行生物等效性评价 ,无显著性差异 (P >0 .0 5 )。结论　两种制剂为生物等效制剂 ,异福片供试品中利福平和异烟肼的相对生物利用度分别为95 .86 %± 11.86 %和 95 .5 4 %± 12 .5 3%。     

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.