国产与进口奥氮平片的人体药动学及生物等效性

目的:考察健康受试者口服奥氮平片的药动学,比较国产制剂与进口制剂的生物等效性.方法:采用双周期两制剂交叉试验设计,22例男性健康志愿者随机分为2组,交叉单次剂量口服国产或进口奥氮平片10mg,用高效液相色谱电化学检测法测定给药后不同时间点血浆中奥氮平的浓度,采用3P97非房室模型法生物等效性计算程序进行统计分析.结果:国产和进口奥氮平片单次口服后的血药浓度时间曲线相似,主要药动学参数Cmax分别为(20.77±4.86)和(19.31±4.80)μg·L-1;Tmax分别为(2.91±0.68)和(3.73±1.24)h;AUC0～144h分别为(643.94±156.35)和(636.53±187.19)μg·h·L1;AUC0～∞分别为(688.42±156.19)和(684.85±192.66)μg·h·L-1.国产奥氮平片对进口奥氮平片的相对生物利用度F-AUC0～144h为(105.2±25.0)%,F-AUC0～∞为(104.8±27.9)%.除Tmax外(P＜0.05),主要药动学参数Cmax,AUC0～144h和AUC0～∞均无显著性差异(P＞0.05).结论:国产和进口奥氮平片具有生物等效性.     

国产替米沙坦片健康人体生物等效性评价

目的:评价国产和进口替米沙坦片剂在健康人体的生物等效性.方法:采用高效液相色谱-荧光检测法测定18名健康志愿者单次、交叉口服替米沙坦片80 mg后血浆替米沙坦浓度.用3P97药动学软件进行药动学参数计算及生物等效性评价.结果:两种替米沙坦片的药-时曲线均符合二室模型,参比制剂、受试制剂的主要药动学参数为:Cmax分别为(931.0±367.7)μg·L-1和(894.2±421.7)μg·L-1;Tmax分别为(1.0±0.6)h和(1.4±0.8)h;T1/2β分别为(28.1±14.1)h和(27.0±10.8)h;AUC0-t分别为(4 085±2 313)μg·L-1·h和(3 920±2 199)μg·L-1·h;AUC0-∞分别为(4 751±2 742)μg·L-1·h和(4 352±2 569)μg·L-1·h.国产替米沙坦片的相对生物利用度F0-t为(97.5±15.6)%,F0-∞为(96.5±15.8)%.结论:方差分析和双单侧t检验证明两制剂具有生物等效性.     

马来酸依那普利片的健康人体生物等效性

目的:研究马来酸依那普利片的人体相对生物利用度和生物等效性.方法:健康志愿者20名,随机双交叉单剂量口服马来酸依那普利片试验制剂和参比制剂,剂量分别为20 mg,用高效液相色谱(HPLC)法测定血浆中依那普利的浓度.用DAS药动学程序计算相对生物利用度并评价两种制剂生物等效性.结果:受试制剂与参比制剂的Cmax分别为(272.6±42.2)μg·L-1和(263.5±42.2)μg·L-1;tmax分别为(0.81±0.11)h和(0.80±0.10)h;AUC(0-∞)分别为(664.7±105.1)μg·h·L-1和(661.2±99.5)μg·h·L-1)AUC(0-inf)分别为(698.0±116.3)μg·h·L-1和(689.0±106.0)μg·h·L-1.试验制剂与参比制剂的人体相对生物利用度为(102.3±19.7)%,结论:试验制剂与参比制剂具有生物学等效性.     

非那雄胺片在健康志愿者的生物等效性研究

目的:比较国产与进口非那雄胺片的人体生物等效性.方法:18例健康男性单次随机交叉口服非那雄胺10mg后,用HPLC法测定血清中各时的药物浓度,计算两者的药物动力学参数和相对生物利用度,进行生物等效性评价.结果:国产及进口非那雄胺片的主要药动学参数如下:AUC0-t分别为(1039.13±272.37)和(1008.60±244.77)μg·h·L-1,Cmax分别为(128.72±26.69)和(117.32±25.20)μg·L-1,Tmax分别为(2.69±0.39)和(2.69±0.49)h,供试制剂相对于参比制剂的人体生物利用度为(106.58±27.79)%.结论:国产与进口非那雄胺片具有生物等效性.     

比较国产与进口利鲁唑片的人体生物等效性

目的:研究利鲁唑片在正常人体内的药动学.方法:采用随机交叉设计,20例健康男性受试者随机交叉口服国产利鲁唑片和进口片剂,服药后0.25～24h内间隔取血.血样加入内标β-奈酚经预处理后用HPLC测定.计算主要药动学参数,并以进口片剂为参比制剂,估算国产利鲁唑片的生物利用度,判断生物等效性.结果:利鲁唑参比片和供试片的药-时曲线均符合二房室模型,其AUC0～24分别为(2 420.1±659.1)和(2 302.8±620.7)μg·h·L-1(P＞0.05);Cmax分别为(654.5±143.1)和(686.1±154.8)μg·L-1(P＞0.05);t1/2分别为(9.48±3.80)和(8.86±3.18)h(P＞0.05);Tmax分别(0.84±0.34)和(0.74±0.24)h(P＞0.05).以进口制剂为对照,用AUC0～24计算的国产片生物利用度为(96.19±12.89)%.结论:本实验建立的分析方法灵敏、准确、简便,统计学结果表明两制剂生物等效.     

西洛他唑片在健康志愿者体内的药动学及生物等效性

目的:研究国产西洛他唑片在人体的药动学和生物等效性.方法:20名男性健康志愿者随机交叉单剂量口服西洛他唑受试和参比制剂(Pletaal)100mg,采用反相高效液相色谱法测定其血药浓度,计算其药动学参数和相对生物利用度,评价两种制剂的生物等效性.结果:西洛他唑受试和参比制剂的主要药动学参数:t1/2分别为(11.9±4.6)h和(11.2±3.0)h,Tmax分别为(3.7±1.2)h和(4.0±1.2)h,Cmax分别为(749.2±348.7)μg·L-1和(655.2±222.1)μg·L-1,AUC0-48分别为(10 088.5±4 606.1)μg·L-1·h和(9 259.0±3 511.8)μg·L-1·h,AUC0-∞分别为(10 926.3±4 713.6)μg·L-1·h和(10 183.4±3 540.7)μg·L-1·h,西洛他唑受试制剂的相时生物利用度为(107.5±14.9)%.结论:经统计学分析,两种制剂具有生物等效性.     

盐酸特比萘芬片的人体生物等效性研究

目的:评价盐酸特比萘芬片人体生物等效性.方法:18例健康志愿者随机交叉口服单剂量(0.25 g)盐酸特比萘芬片试验制剂与参比制剂,采用LC-MS/MS法测定血浆中特比萘芬的血药浓度.结果:试验制剂与参比制剂的主要药动学参数Cmax分别为(941.6±196.5)和(917.1±264.8)μg·L-1,Tmax分别为(1.38±0.39)和(1.38±0.61)h,AUC0～72h分别为(4 696.4±1 192.8)和(4 596.9±1 189.8)μg·h·L-1,AUC0～∞分别为(4 838.7±1 188.1)和(4 755.9±1 183.2)μg·h·L-1.试验制剂对参比制剂的相对生物利用度F(以AUC0～72h作为评价依据)为(98±9)%.结论:盐酸特比萘芬片试验制剂与参比制剂生物等效.     

辛伐他汀片及其活性代谢产物在中国健康人体的药动学和生物等效性评价

目的:研究辛伐他汀片及其活性代谢物辛伐他汀酸在健康人体内的药动学特征和生物等效性评价。方法:24名健康受试者随机交叉、单剂量口服40 mg参比和试验辛伐他汀片后;采用LC-MS/MS测定血浆中辛伐他汀和辛伐他汀酸的浓度;应用DAS2.1.1软件计算药动学参数,并进行生物等效性评价。结果:参比和试验制剂辛伐他汀的主要药动学参数如下:Cmax分别为(6.8±4.0)μg·L-1和(6.9±4.5)μg·L-1;tmax分别为(2.4±1.9)h和(2.2±1.5)h;t1/2分别为(5.0±2.6)h和(6.3±6.7)h;AUC0-24分别为(38.1±27.0)μg·h·L-1和(36.5±24.2)μg·h·L-1;AUC0-∞分别为(40.7±29.3)μg·h·L-1和(41.8±28.7)μg·h·L-1。参比和试验制剂辛伐他汀酸的主要药动学参数如下:Cmax分别为(3.8±1.7)μg·L-1和(3.8±1.6)μg·L-1;tmax分别为(4.3±1.6)h和(4.2±1.0)h;t1/2分别为(5.8±3.2)h和(7.3±6.9)h;AUC0-24分别为(30.1±11.1)μg·h·L-1和(30.0±10.5)μg·h·L-1;AUC0-∞分别为(34.0±14.4)μg·h·L-1和(35.6±17.4)μg·h·L-1。以AUC0-24计算辛伐他汀和辛伐他汀酸的相对生物利用度分别为(105.7±55.6)%和(106.5±42.8)%。结论:经方差分析及双单侧t检验结果显示,辛伐他汀与辛伐他汀酸的试验制剂和参比制剂在人体内生物等效。     

理舒达人体药动学和相对生物利用度研究

目的:研究理舒达(辛伐他汀胶囊)的人体药动学和相对生物利用度.方法:采用双周期随机交叉试验设计.分别给予10例男性健康受试者理舒达或对照药(进口辛伐他汀片)20mg后,采用GC-MS检测法测定血浆中药物浓度.结果:试验药与对照药的主要药动学参数Cmax,Tmax,CL/F,t1/2,AUC0～24和AUC0～∞分别为(2.49±0.57)和(2.58±0.50)μg·L-1;(3.2±0.4)和(3.1±0.3)h;(2.08±0.59)×103和(2.17±0.47)×103L·h-1;(6.20±0.64)和(5.74±0.67)h;(18.20±4.06)和(17.84±3.59)μg·h·L-1;(19.32±3.59)和(19.80±4.05)μg·h·L-1.试验药的相对生物利用度F为(101.9±8.6)%.结论:试验药理舒达与对照药具有生物等效性.     

国产盐酸丁螺环酮片的人体相对生物利用度

目的:研究盐酸丁螺环酮片的药动学及相对生物利用度。方法:受试者交叉口服单剂量(15mg)受试制剂和参比制剂,用高效液相色谱法测定血药浓度。结果:受试及参比制剂的主要药动学参数Tmax分别为(0.87±0.18)h与(0.81±0.09)h,Cmax分别为(25.2±8.0)μg.L-1与(25.1±7.9)μg.L-1,AUC0?t分别为(52.7±17.9)μg.h.L-1与(51.9±17.2)μg.h.L-1,AUC0?∞分别为(55.1±18.2)μg.h.L-1与(54.9±17.0)μg.h.L-1,T1/2分别为(2.8±0.5)h与(2.8±0.4)h。两种制剂主要药动学参数比较差异无显著性(P>0.05),受试制剂相对于参比制剂的生物利用度为(102.7±5.9)%。结论:两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.