苯磺酸氨氯地平片在健康人体的生物等效性

目的 研究苯磺酸氨氯地平片(抗高血压药)的相对生物利用度,并求证该制剂的生物等效性.方法 24名男性健康受试者随机交叉给药,先后口服单剂量试验制剂及参比制剂苯磺酸氨氯地平片剂5 mg,采用LC-MS/MS法测定血药浓度,计算2者的药代动力学参数及相对生物利用度,并评价2制剂的生物等效性.结果 口服试验制剂及参比制剂5 mg的主要药代动力学参数如下:t1/2分别为(47.15±17.28)、(43.22 ± 16.63)h;tmax分别为(5.81±2.09)、(6.38±2.33)h;Cmax分别为(4.77±1.28)、(4.37±1.14)ng·mL-1;AUC0-t分别为(176.39±57.95)、(182.55±58.36)ng·mL-1h;AUC0-t分别为(185.65±59.01)、(192.83±62.72)ng·mL-1h;试验制剂对于参比制剂的平均相对生物利用度F值:AUC0-t为(98.1±18.5)%,AUC0-∞为(98.6±20.0)%;tmax经非参数检验无显著性差异,试验制剂的平均生物利用度(AUC0-t、AUC0-∞)均大于98%,2种制剂的Cmax、AUC0-t和AUC0-∞双向单侧t检验和[1-2α]置信区间法的等效性分析均为合格,tmax经非参数秩和检验无显著性差异.结论 2种氨氯地平片剂为生物等效制剂.     

奥硝唑片在健康人体的生物等效性

目的 评价奥硝唑片(抗厌氧菌药)试验制剂与国产上市剂型在健康人体的生物等效性.方法 22例健康男性受试者随机分组,按照自身对照单次口服奥硝唑片1500 mg后,用高效液相色谱法测定血浆中奥硝唑的浓度,采用DAS软件计算主要药代动力学参数.结果 试验制剂和参比制剂的主要药代动力学参数如下:t1/2分别为(13.69±3.20)h和(14.31±4.30)h;tmax分别为(1.89 ±1.26)h和(1.73±1.10)h;Cmax分别为(29.13±3.57)μg·mL-1和(28.22±4.19)μg·mL-1;AUC0-t分别为(619.3±98.9)μg·h·mL-1和(601.1±92.9)μg·h·mL-1;AUC0-∞分别为(626.4±102.0)μg·h·mL-1和(609.0±94.3)μg·h·mL-1.试验制剂对于参比制剂的平均相对生物利用度F按照AuC0-t与AUC0-∞计算分别为(103.4±10.1)%,(103.2±10.1)%.结论 试验制剂和参比制剂为生物等效性制剂.同时2种制剂服用安全,耐受性良好.     

乳酸左氧氟沙星分散片健康人体生物等效性研究

目的对乳酸左氧氟沙星分散片和左氧氟沙星片进行生物利用度比较,判定两种制剂是否为等效制剂。方法20名男性健康受试者随机交叉给药,分别口服单剂量乳酸左氧氟沙星分散片(试验制剂)及乳酸左氧氟沙星片(参比制剂)200mg,采用HPLC法测定血药浓度,计算两者的药动学参数及相对生物利用度,并求证两种制剂的生物等效性。结果口服200mg试验制剂或参比制剂的主要药动学参数t1/2β分别为(5.68±1.79)和(5.38±1.52)h;tmax分别为(0.84±0.79)和(0.95±0.47)h;cmax分别为(2.27±0.47)和(2.26±0.58)μg.mL-1;AUC0-t分别为(14.90±2.14)和(15.62±2.49)μg.mL-1.h;AUC0-∞分别为(15.17±2.34)和(15.87±2.67)μg.mL-1.h。试验制剂对于参比制剂的平均相对生物利用度F值:AUC0-t为(97.23±17.71)%,AUC0-∞为(97.43±17.76)%。两种制剂的AUC0-t,AUC0-∞及cmax经对数转换后双单侧t检验,结果接受两种制剂生物等效的假设。cmax的90%置信区间结果为88.1%～117.3%,AUC0-t为89.2%～102.5%,AUC0-∞为89.3%～102.9%,tmax经秩和检验无显著性差异。整个试验期间,受试者均未发生药物不良反应。结论按照生物等效性判定标准,可判定两种制剂生物等效。     

格列喹酮片在健康人体生物等效性研究

目的:研究两种格列喹酮片在健康人体内的药动学特征,并评价两种制剂间的生物等效性。方法:18名健康男性志愿受试者随机交叉单剂量口服试验制剂和参比制剂60 mg,清洗期1周,采用HPLC法测定血清中格列喹酮浓度。结果:受试者口服试验制剂和参比制剂后,主要药代动力学参数如下:t1/2分别为(4.78±1.87),(4.19±1.57)h,tmax分别为(3.06±1.08),(3.28±1.49)h,Cmax分别为(0.87±0.35),(0.90±0.33)μg.mL-1,AUC0-t分别为(4.35±1.66),(4.62±1.23)μg.h.mL-1,AUC0-∞分别为(4.98±1.72),(5.19±1.42)μg.h.mL-1。试验制剂的相对生物利用度AUC0-t为(95.8±34.1)%,AUC0-∞为(97.7±29.4)%。结论:两种格列喹酮片为生物等效制剂。     

石杉碱甲缓释片多剂量给药在健康人体的生物等效性

目的 研究石杉碱甲缓释片(中枢兴奋药)多剂量给药在健康人体的相对生物利用度及生物等效性.方法 采用双周期自身随机交叉试验设计.24名健康受试者多次口服试验制剂或参比制剂,用液相色谱-串联质谱测定血浆中药物浓度,药代动力学参数用DAS软件处理获得.结果 试验制剂石杉碱甲缓释片组与参比制剂石杉碱甲片组的Cmin(ss)分别为(0.54±0.21)和(0.78±0.20)ng·mL-1;Cmax(ss)分别为(1.65±0.45)和(1.83±0.37)ng·mL-1;Css分别为(1.05±0.28)和(1.22±0.28)ng·mL-1;tmax分别为(3.50±1.90)和(1.10±0.40)h;AUC0-t(ss)分别为(30.70±8.20)和(35.10±8.93)ng·h·mL-1;AUC0-∞(ss)分别为(36.90±10.30)和(41.30±11.10)ng·h·mL-1;AUCss分别为(25.30±6.80)和(14.60±3.41)ng·h·mL-1;受试制剂的生物利用度F0-tn为(87.7±11.6)%.受试制剂和参比制剂的AUC0-t和AUC0-∞经对数转换后进行方差分析,2制剂间无显著性差异(P＞0.05).2制剂间tmax有显著差异(P＜0.05),受试制剂tmax明显比参比制剂有所延长,具有缓释的特征.结论 国产石杉碱甲缓释片与石杉碱甲片具有生物等效性,同时受试制剂具有明显的缓释特征.     

克拉霉素分散片的健康人体生物等效性研究

目的:研究克拉霉素分散片在健康人体的药动学及生物等效性.方法:采用两制剂双周期双交叉前后自身对照试验设计.20名健康志愿者分别口服克拉霉素分散片受试制剂或参比制剂500 mg,采用高效液相色谱-质谱法(LC-MS)测定血浆中克拉霉素的浓度,经DAS 2.1软件处理后得药动学数据,并进行等效性检验.结果:受试制剂的t1/2为(3.72±0.42)h,Cmax为(2 350.7±604.2)ng·mL-1,Tmax为(1.48±0.36)h,AUC0-t为(12 425±1 975)ng·h·mL-1;参比制剂的t1/2为(4.22±1.15)h,Cmax为(2 045.0±379.5)ng·mL-1,Tmax为(1.76±0.52)h,AUC0-t为(11 954±2 152)ng·h·mL-1.以AUC0-t计算,与参比制剂比较,受试制剂平均相对生物利用度为(101.7±7.3)%,AUC0-t,AUC-∞和Cmax均拒绝生物不等效假设.结论:测定结果经方差分析及双单侧t检验,表明两种制剂具有生物等效性.     

洛芬葡锌那敏分散片中布洛芬与复方锌布颗粒中布洛芬在健康人体的生物等效性

目的建立准确、灵敏的液相色谱-质谱联用法(LC-MS/MS),并比较健康受试者单剂量口服洛芬葡锌那敏(非甾体抗炎药)分散片(受试制剂)和复方锌布颗粒(参比制剂)后的生物等效性。方法采用随机开放、双周期自身交叉单剂量给药试验设计(清洗期为2周)。20名志愿受试者分别单次空腹口服等剂量洛芬葡锌那敏分散片(受试制剂)和复方锌布颗粒(参比制剂)(相当于布洛芬300 mg)。以吲达帕胺为内标,用ESI负离子选择性反应监测(SRM)模式测定血浆中布洛芬浓度,计算药代动力学参数及进行临床生物等效性评价。结果洛芬葡锌那敏分散片(受试制剂)中布洛芬的Cm ax为(24.11±12.15)μg.mL-1,tm ax为(2.23±0.84)h,AUC0-t为(70.81±31.02)μg.h.mL-1,AUC0-∞为(72.67±31.11)μg.h.mL-1,t1/2为(1.59±0.32)h。复方锌布颗粒(参比制剂)中布洛芬的Cm ax为(24.94±9.25)μg.mL-1,tm ax为(1.81±0.84)h,AUC0-t为(70.53±27.31)μg.h.mL-1,AUC0-∞为(72.81±27.08)μg.h.mL...     

左氧氟沙星分散片人体相对生物利用度及生物等效性研究

目的 研究国产左氧氟沙星片剂的相对生物利用度,并且评价该制剂的生物等效性.方法 20名男性健康受试者随机交叉双周期给药,分别口服单剂量左氧氟沙星试验制剂及参比制剂,采用反相高效液相色谱法测定血药浓度,计算两者的药动学参数及相对生物利用度,并评价试验制剂的生物等效性.结果 口服左氧氟沙星200 mg试验和参比制剂的主要药代力学参数,t1/2分别为(11.0±3.2)h和(9.5±2.6)h;Tmax分别为(0.90±0.46)h和(1.3±0.62)h;Cmax分别为(2.7±0.75)μg·mL-1和(2.65±0.70)μg·mL-1; AUC0～T分别为(16.6±3.0)μg·h·mL-1和(16.5±2.6)μg·h·mL-1;AUC0～∞分别为(18.2±3.9)μg·h·mL-1和(19.2±3.5)μg·h·mL-1.按实测值AUC0-T 计算,试验制剂对于参比制剂的平均相对生物利用度为(100.6±10.2)%.Cmax、AUC0-T和AUC0-∞三个药动学参数制剂间均无显著性差异(P>0.05),服药周期对Cmax,AUC0-T和AUC0-∞三个参数亦无明显影响(P>0.05),Cmax、AUC0-T和AUC0-∞三个药动学参数均存在明显的个体间差异(P<0.05).统计结果显示,AUC0-T的置信区间为100.7%～113.0%,AUC0-∞的置信区间为100.1%～112.2%,Cmax的置信区间为95.0%～115.4%,均符合等效标准;Cmax,AUC0-T和AUC0-∞三个参数的双向t检验结果同样符合等效标准;Tmax经非参检验结果合格.结论 左氧氟沙星分散片试验制剂相对参比制剂生物等效.     

精氨洛芬片剂与颗粒剂在健康受试者体内的生物等效性

目的 研究精氨洛芬(非甾体抗炎药)片剂与颗粒剂在中国健康志愿者体内的生物等效性.方法 20名健康男性受试者分别随机交叉口服精氨洛芬片(试验制剂)及其颗粒(参比制剂)0.4 g,用HPLC-UV法测定给药后不同时间点的血浆布洛芬浓度;用DAS程序对试验数据进行统计处理,评价2种制剂的生物等效性.结果 试验制剂和参比制剂的药代动力学参数如下:Cmax分别为(50.60±9.12)、(50.53±8.58)nag·L-1,tmax分别为(0.51±0.20)、(0.34±0.11)h,AUC0～t分别为(118.63±21.42)、(115.75±20.23)mg·h·L-1,AUC0～∞分别为(121.18±22.18)、(118.55±21.83)mg·h·L-1.试验制剂与参比制剂AUC0-t之比和Cmax之比的90%可信区间分别为97.5%～107.6%和93.3%～107.2%.结论 试验制剂和参比制剂吸收程度等效(AUC0-t,AUC0-∞和Cmax均生物等效性);但吸收速度不等效(tmax不等效).     

国产酒石酸唑吡坦的生物利用度和生物等效性研究

目的:研究国产酒石酸唑吡坦在中国健康受试者体内的生物利用度和生物等效性.方法:采用高效液相色谱法测定18例健康受试者单剂量口服受试制剂或参比制剂10 mg后血浆中唑吡坦的浓度,采用BAPP2.0生物统计软件对2种制剂的Cmax,Tmax和AUC0-t进行统计分析.结果:酒石酸唑吡坦受试制剂与参比制剂的实测Tmax均为(0.9±0.3)h,实测Cmax分别为(173.94±57.49)和(173.74±47.99)μg·L-1, 梯形法计算AUC0-t分别为(543.19±252.06)和(551.01±254.65)μg·h·L-1,t1/2Ke分别为(2.22±0.61)和(2.12±0.40)h.2种制剂的主要药动学参数经统计分析差异无显著性.酒石酸唑吡坦受试片剂的相对生物利用度为(99.9±20.7)%.结论:受试制剂和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.

---

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.

     

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.     

2-(Acetoxyphenyl)-(Z)-styryl sulfides as cyclooxygenase inhibitors

2-(Acetoxyphenyl)-(Z)-styryl sulfides are described as selective cyclooxygenase-2 (COX-2) inhibitors, useful for treating inflammation and COX-2-mediated disorders including neoplasia. 2-(Acetoxyphenyl)-(Z)-styryl sulfide is claimed to be the most potent COX inhibitor in the series with a COX-2 selectivity ratio of 33. This compound is also claimed to be superior to celecoxib (Celebrex^®, Pfizer) in inhibiting cell growth of colorectal carcinoma cells. In this evaluation, the COX inhibitory activity of this compound is compared to that previously disclosed for diarylheterocycles and 2-(acetoxyphenyl)alkyl sulfides. The validity of the DLD-1 cell line in the growth inhibition studies is questioned based on recent literature reports indicating the lack of COX-2 expression in this cell line.     

Sleep-disordered breathing with chronic opioid use

Chronic opioid use for pain relief or as substitution therapy for illicit drug abuse is prevalent in our societies. In the US, retail distribution of methadone and oxycodone has increased by 824 and 660%, respectively, between 1997 and 2003. μ-Opioids depress respiration and deaths related to illicit and non illicit chronic opioid use are not uncommon. Since 2001 there has been an emerging literature that suggests that chronic opioid use is related to central sleep apnoea of both periodic and non-periodic breathing types, and occurs in ～ 30% of these subjects. The clinical significance of these sleep-related abnormalities are unknown. This review addresses the present knowledge of control of ventilation mechanisms during wakefulness and sleep, the effects of opioids on ventilatory control mechanisms, the sleep-disordered breathing found with chronic opioid use and a discussion regarding the future research directions in this area.     

Drug targets for cognitive enhancement in neuropsychiatric disorders

The investigation of novel drug targets for treating cognitive impairments associated with neurological and psychiatric disorders remains a primary focus of study in central nervous system (CNS) research. Many promising new therapies are progressing through preclinical and clinical development, and offer the potential of improved treatment options for neurodegenerative diseases such as Alzheimer's disease (AD) as well as other disorders that have not been particularly well treated to date like the cognitive impairments associated with schizophrenia (CIAS). Among targets under investigation, cholinergic receptors have received much attention with several nicotinic agonists (α7 and α4β2) actively in clinical trials for the treatment of AD, CIAS and attention deficit hyperactivity disorder (ADHD). Both glutamatergic and serotonergic (5-HT) agonists and antagonists have profound effects on neurotransmission and improve cognitive function in preclinical experiments with animals; some of these compounds are now in proof-of-concept studies in humans. Several histamine H3 receptor antagonists are in clinical development not only for cognitive enhancement, but also for the treatment of narcolepsy and cognitive deficits due to sleep deprivation because of their expression in brain sleep centers. Compounds that dampen inhibitory tone (e.g., GABA_A α5 inverse agonists) or elevate excitatory tone (e.g., glycine transporter inhibitors) offer novel approaches for treating diseases such as schizophrenia, AD and Down syndrome. In addition to cell surface receptors, intracellular drug targets such as the phosphodiesterases (PDEs) are known to impact signaling pathways that affect long-term memory formation and working memory. Overall, there is a genuine need to treat cognitive deficits associated with many neuropsychiatric conditions as well as an increasingly aging population.