国产与进口盐酸沙格雷酯片在健康人体的生物等效性

目的 研究国产与进口盐酸沙格雷酯片(抗血栓药)的相对生物利用度,评价2者的生物等效性.方法 采用双周期自身交叉试验设计,单剂量口服给药.24名健康男性受试者分别单剂量口服受试制剂和参比制剂,血浆样品采用高效液相色谱-串联质谱法检测.结果 受试制剂及参比制剂盐酸沙格雷酯片的主要药代动力学参数:Cmax分别为(710.25±305.79),(653.33±311.06)μg·L-1;tmax分别为(0.39±0.23),(0.38±0.19)h;t1/2分别为(0.72±0.10),(0.67±0.10)h;AUC0-tn分别为(473.80±216.83),(440.17±440.17)μg·h·L-1;AUC0-∞分别为(479.88±224.77),(443.79±144.70)μg·h·L-1;受试制剂盐酸沙格雷酯片的相对生物利用度F0-tn、F0-∞分别为(110.24±38.24)%,(110.64±39.07)%.结论 受试制剂和参比制剂具有生物等效性.     

富马酸酮替芬颗粒与富马酸酮替芬片在健康人体的生物等效性

目的 研究富马酸酮替芬颗粒与富马酸酮替芬片(均为平喘药)的相对生物利用度,评价2者的生物等效性.方法 采用双周期自身交叉试验设计,单剂量口服给药.24例健康男性受试者分别单剂量口服受试制剂和参比制剂,血浆样品采用高效液相色谱串联质谱法检测.结果 受试制剂富马酸酮替芬颗粒及参比制剂富马酸酮替芬片的主要药代动力学参数:Cmax分别为(247.76±99.61),(229.24±96.44)ng·L-1;tmax分别为(2.38±0.97),(2.46±1.14)h;t1/2分别为(14.85±5.76),(14.69±7.91) h;AUC0-tn分别为(2641.07±1025.19),(2764.19±1231.50) ng·L-1·h;AUC0-∞分别为(3192.01±1272.20),(3431.11±1902.72) ng·L-1·h;受试制剂富马酸酮替芬颗粒的相对生物利用度F0-tn、F0-∞分别为(100.08±21.81)%,(102.75±30.33)%.结论 受试制剂和参比制剂具有生物等效性.     

硫唑嘌呤片在健康人体的生物等效性

目的研究硫唑嘌呤片(免疫抑制剂)在健康人体的相对生物利用度并评价其生物等效性。方法20名健康志愿者自身交叉、单剂量口服硫唑嘌呤受试和参比制剂各100 mg后,用反相高效液相色谱法测定血浆中其代谢物6-巯基嘌呤浓度。应用DAS软件计算药代动力学参数和相对生物利用度。结果6-巯基嘌呤受试制剂和参比制剂的平均药物浓度-时间曲线均符合一室模型,主要药代动力学参数:t1/2分别为(1.30±0.25),(1.30±0.34)h;tmax分别为(1.25±0.16),(1.24±0.21)h;Cmax分别为(48.44±17.09),(52.32±24.37)μg.L-1;AUC0-t分别为(89.49±19.25),(91.90±25.31)μg.h.L-1;AUC0-∞分别为(96.11±19.74),(98.36±24.66)μg.h.L-1。与参比制剂比较,受试制剂的相对生物利用度F0-t为(99.62±15.29)%,F0-∞为(99.39±13.59)%。结论2种硫唑嘌呤制剂具有生物等效性。     

奈韦拉平片在健康人体的药代动力学和生物等效性

目的 研究2种国产奈韦拉平片(抗病毒药)在健康人体内的药代动力学,并评价这2种制剂的生物等效性.方法 20例健康成年男性受试者随机分组,按自身对照单次口服奈韦拉平片200 mg后,采用HPLC法测定奈韦拉平的血浆浓度,非房室模型法计算各主要药代动力学参数,并进行方差分析和生物等效性评价.结果 参比制剂与受试制剂奈韦拉平的tmax分别为(3.5±2.1)、(3.0±1.9)h;Cmax分别为(2.6.±0.5)、(2.6±0.5)mg·L-1;t1/2分别为(57.6±10.4)、(58.6±10.2)h;MRT分别为(55.6±6.5)、(56.8±5.0)h;AUC0-t分别为(167.6±36.1)、(171.8±32.7)mg·L-1·h;AUC0→∞分别为(169.9±36.6)、(174.2±33.1)mg·L-1·h;CL/F分别为(1.2±0.3)、(1.2±0.2)L·h-1;Vd/F分别为(100.3±20.4)、(99.4±20.8)L;受试制剂相对于参比制剂的生物利用度为(103.7±11.6)%.结论 受试制剂与参比制剂具有生物等效性.     

尼莫地平缓释片在中国健康人体的生物等效性

目的 研究尼莫地平(抗缺血性脑损伤药)缓释片的相对生物利用度,并评价其生物等效性.方法 采用随机交叉试验设计,20名中国健康男性志愿者分别单次和多次口服尼莫地平缓释片受试制剂与参比制剂,用液相色谱一串联质谱法测定血浆中尼莫地平的血药浓度,计算药代动力学参数及相对生物利用度.结果 单次口服2种尼莫地平缓释片,受试制剂和参比制剂的主要药代动力学参数:tmax分别为(2.63±0.71),(2.88±0.79)h;Cmax分别为(13.18±5.21),(13.05±5.11)μg·L-1;t1/2分别为(3.15±0.79),(3.34 ±1.10)h;MRT0-1分别为(5.58±0.93),(5.78 ±1.06)h;MRT0-∞分别为(5.93±0.89),(6.24 ±1.14)h;AUC0-t分别为(73.84±28.09),(76.85±30.09)μg·h·L-1;AUC0-∞.分别为(75.24±28.18),(78.58±30.08)μg·h·L-1;F为(97.70±12.10)%.连续多次口服2种尼莫地平缓释片,给药第3 d血药浓度达稳态后,受试制剂和参比制剂主要药代动力学参数:tmax分别为(2.43±0.37),(2.40±0.38)h;C-max分别为(17.51±4.22),(16.52 ±4.16)μg·L-1;C-min分别为(3.58±1.92),(2.96 ±1.67)±μg·L-1;Cav分别为(7.29±1.97),(7.23±2.15)μg·L-1;t1/2分别为(4.10±1.42),(3.78±1.09)h;MRT0-t分别为(5.63 ±0.82),(5.71±0.92)h;MRT0-t分别为(6.65 ±1.47),(6.37±o.96)h;AUCss 分别为(87.44±23.69),(86.74±25.75)μg·h·L-1;DF分别为(1.99±0.72),(1.96±0.68);F为(102.20±10.70)%.结论 受试制剂与参比制剂具有生物等效性.     

盐酸克林霉素胶囊在中国健康受试者体内的药代动力学及生物等效性研究

目的评价盐酸克林霉素胶囊在中国健康受试者中的药代动力学特征,并评价两种制剂的生物等效性。方法空腹、餐后各入组24例健康受试者,采用随机、开放、两序列、两周期双交叉给药的试验设计,受试者单次口服盐酸克林霉素胶囊受试药物和参比药物150 mg,采用液相色谱-串联质谱法(LC-MS/MS)检测人血浆中克林霉素的浓度,使用WinNonlin7.0软件计算药代动力学参数,评价两种制剂的生物等效性。结果单剂量空腹给药受试药物和参比药物克林霉素的主要药代动力学参数如下:Cmax分别为(2.91±0.86),(2.83±0.83)μg·mL^-1,AUC0-t分别为(7.86±3.06),(7.39±2.39)μg·h·mL^-1,AUC0-∞分别为(8.06±3.23),(7.59±2.50)μg·h·mL^-1。单剂量餐后给药受试药物和参比药物克林霉素后的主要药代动力学参数如下:受试制剂和参比制剂的Cmax分别为(1.98±0.52),(2.05±0.41)μg·mL^-1,AUC0-t分别为(9.68±3.35),(9.16±2.66)μg·h·mL^-1,AUC0-∞分别为(9.53±2.98),(9.60±3.24)μg·h·mL^-1。两药物的主要药代动力学参数Cmax、AUC0-t、AUC0-∞经对数转换后进行方差分析,其90%置信区间空腹状态下分别为94.75%~111.37%,198.81%~111.74%,98.34%~111.66%;餐后状态下分别为84.81%~104.19%、94.33%~112.92%,93.99%~113.64%。结论空腹和餐后状态下,两种盐酸克林霉素胶囊的主要药代动力学参数相近,具有生物等效性。     

普伐他汀片在健康人体的生物等效性

目的 建立测定血浆普伐他汀的高效液相色谱一串联质谱法,并评价普伐他汀钠片(降血脂药)试验制剂与参比制剂的相对生物利用度和生物等效性.方法 按两种制剂双周期自身对照交叉试验设计,20名男性健康志愿者分别单剂量口服2种普伐他汀钠片(参比制剂和受试制剂)40 mg后,用高效液相色谱一串联质谱法测定血药浓度,计算药代动力学参数,并评价2种制剂的生物等效性.结果 口服普伐他汀钠片参比制剂及受试制剂40 mg后的主要药代动力学参数:tmax分别为(0.79±0.28),(0.88±0.32) h; Cmax分别为(55.06±22.09),(57.75±30.47) mg·L-1;t1/2分别为(2.38±0.69),(2.31±0.49) h;AUCO-t分别为(110.49±45.25 ),(108.81±52.16)ng·h·L-1; AUC0-∞分别为(115.58±47.08),(113.60±54.38) mg·h·L-1.受试制剂对参比制剂平均相对生物利用度为(103.76±16.70)%.结论 2种普伐他汀钠片生物等效.     

洛伐他汀胶囊在健康人体的生物等效性研究

目的:考察两种洛伐他汀胶囊在健康人体的生物等效性.方法:20名健康男性志愿者单剂量口服试验制剂或参比制剂,采用LC/MS/MS法测定全血中药物浓度,用DAS2.1软件计算药代动力学参数.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(4.67±2.34),(5.30±2.62)h;tmax分别为(1.90±0.50),(2.13±0.39)h;Cmax分别为(8.37±0.84),(8.29±1.00)ng·mL-1;AUC0-t分别为(32.25±6.49),(32.71±7.59)ng.h·mL-1;AUC0-∞分别为(33.62±6.94),(34.71±8.62)ng·h·mL-1.试验制剂的相对生物利用度F=(99.60±8.30)%.结论:受试制剂和参比制剂具有生物等效性.     

烟酸缓释片在健康人体的生物等效性

目的 研究烟酸缓释片(广谱凋血脂药)在健康人体的药代动力学,并评价其生物等效性.方法 30名男性健康志愿者随机交叉单剂量口服试验制剂或参比制剂1.5 g,用高效液相色谱-串联质谱法测定血浆中烟酸浓度.结果 单剂量口服烟酸试验制剂或参比制剂1.5 g,药代动力学参数如下:AUC0-t分别为(20.05±16.29),(21.61±18.06)μg·h·mL-1;AUC0-∞分别为(20.81±16.30),(22.81±18.47)μg·h·mL-1;Cmax分别为(8.72±6.81),(9.57±8.22)μg·mL-1;tmax分别为(4.41±1.34),(4.31±1.29)h;t1/2分别为(4.00±4.90),(2.91±3.39)h,烟酸缓释片的相对生物利用度为(96.6±30.9)%.结论 受试制剂与参比制剂生物等效.     

甲磺酸酚妥拉明口腔崩解片在健康人体的药代动力学和生物等效性

目的 研究甲磺酸酚妥拉明(抗男性勃起功能障碍药)口腔崩解片和分散片在健康人体的药代动力学及生物等效性.方法 20名健康志愿者随机双交叉、单剂量口服受试制剂和参比制剂,剂量均为40 mg,剂间间隔为1周,用反相高效液相色谱-紫外检测法测定血浆中甲磺酸酚妥拉明浓度,用DAS药代动力学程序计算有关药代动力学参数、相对生物利用度,并评价2种制剂生物等效性.结果 受试与参比制剂的药代动力学参数tmax分别为(0.69±0.20)和(0.81±0.32)h,t1/2分别为(4.99±1.48)和(4.41±1.73)h,Cmax分别为(34.50±8.79)和(35.17±11.19)mg·L-1,AUC0-t分别为(100.30±23.14)和(99.95±27.51)mg·h·L-1,AUC0-∞分别为(104.81±23.46)和(104.85±28.61)mg·h·L-1.甲磺酸酚妥拉明的相对生物利用度为(103.10±20.60)%.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.

     

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.