RP-HPLC测定加替沙星滴眼液的含量

目的 建立测定加替沙星滴眼液含量的高效液相色谱法.方法 采用Hypersil ODS C18柱(5μm,4.6 mm×250 mm)为色谱柱,流动相为1%三乙胺溶液(磷酸调pH至4.5)-乙腈(86:14,v/v),流速为0.9 ml/min,检测波长325 nm,柱温50℃.结果 加替沙星线性范围为7.5-240 μg/ml,r=0.9999;平均回收率为99.7%,RSD=0.40%.结论 该方法简便、快速、灵敏,可作为该制剂含量测定.     

HPLC法测定不同产地川芎中阿魏酸的含量

目的:建立HPLC法,测定不同产地川芎中阿魏酸含量.方法:采用DiamonsilTM(钻石)C18色谱柱(250mm×4.6mm,5μm),流动相为甲醇-水-冰醋酸(30:68:2v/v),流速为1.0mL·min-1,检测波长为320nm.结果:阿魏酸质量浓度在3.16～31.6mg·L-1内呈良好的线性关系,平均回收率为98.0%,RSD为1.47%(n=9),4个产地川芎中的阿魏酸质量百分含量分别为0.198%、0.208%、0.217%、0.187%.结论:本法可用于川芎中阿魏酸的含量测定;44个产地川芎中以四川省都江堰市产川芎中阿魏酸含量最高.     

高效液相色谱法测定氯强油搽剂中氯霉素和醋酸泼尼松的含量

目的:建立高效液相色谱法测定氯强油搽剂中氯霉素和醋酸泼尼松的含量。方法:测定氯霉素含量用Spherisorb C18柱(4.6mm×250mm,5μm),流动相为甲醇-0.02mol.L-1磷酸二氢钾(用磷酸调pH至3.0)(60∶40,v/v),流速为0.9mL.min-1,检测波长为242nm;测定醋酸泼尼松含量用C18色谱柱(4.6mm×250mm,5μm),以甲醇-水(60∶40,v/v)为流动相,检测波长为240nm,流速为1.0mL.min-1。结果:氯霉素在100.1~500.4mg.L-1范围内线性关系良好(r=0.999 6),平均回收率为100.2%;醋酸泼尼松在10~150mg.L-1范围内线性关系良好,峰面积积分值与浓度呈良好线性关系(r=0.999 6);平均回收率为99.4%(RSD=1.7%)。结论:高效液相色谱法可以用于该制剂得含量测定和质量控制,方法简便、灵敏、结果准确。     

高效液相色谱法测定利福布汀的含量

目的 建立测定利福布汀的HPLC方法,并测定市售胶囊制剂中利福布汀的含量.方法 以Lichrospher100(RP-85.0μm×250mm)为分析柱,乙腈-甲醇-0.04mol/LKH2PO4(54:10:36,v/v)为流动相,流速1ml/min,柱温:40℃,进样量:5.0μl,254nm处紫外检测;对硝基苯酚为内标.结果 利福布汀在3.75～150.00μg/ml范围内,峰面积对浓度呈良好的线性关系(r=0.99987),平均回收率为100.24%,RSD为0.90%(n=6).结论 本法简便、快速、准确、灵敏度高、重现性好,适用于利福布汀的质量控制和临床血药浓度的监测.     

高效液相色谱法测定西罗莫司血药浓度

目的:建立快速测定人全血中西罗莫司浓度的高效液相色谱方法.方法:色谱柱为Zorbax Eclipse XDB C18(4.6mm×150mm,5μm);流动相为甲醇-乙腈-去离子水(50∶22∶28,v/v);流速1.2mL·min-1;紫外检测波长278nm;柱温50℃.结果:西罗莫司浓度测定的线性范围为2.5～50.0μg·L-1,最低检测浓度为2.0μg·L-1,平均回收率为103.2%,日内RSD小于5%,日间RSD小于4%.结论:本方法简便、快速,定量准确,可用于西罗莫司临床药动学研究,也可用于西罗莫司常规血药浓度监测.     

反相高效液相色谱法测定维生素E霜中维生素E的含量

目的:探讨测定维生素E霜中维生素E含量的方法.方法:采用反相高效液相色谱法,以Nova-pak C18柱(3.9mm×150mm,4μm)为色谱柱,甲醇-水(98:2)为流动相,检测波长285 nm,流速1 mL/min,柱温25℃,进样10μL测定维生素E的含量.结果:维生素E在1.2～6.0μg/mL浓度范围内与峰面积呈良好的线性关系,测得样品平均回收率为98.87%,RSD为1.03%,样品中维生素E的含量分别为19.8,19.5,19.7 mg/g.结论:反相高效液相色谱法操作简便快速,结果准确可靠,适用于维生素E霜中维生素E的含量测定.     

高效液相色谱法测定槐米中槲皮素的含量

目的建立槐米中槲皮素的含量测定方法。方法利用甲醇-0.4%磷酸溶液(60∶40,v/v)检测波长375 nm,其中甲醇为色谱纯,磷酸为分析纯,流速为0.8 mL/min。色谱柱:Diamonsil(TM)C18(416 mm×250 mm,5μm)。结果槲皮素在1.964¹9.64 mg/mL的浓度范围内峰面积和浓度呈良好的线性关系r=0.9994;测得回收率为98.6%,RSD为1.8%。结论方法准确可靠、简便,适用于槐米中槲皮素的含量测定。     

反相高效液相色谱法测定GCLE含量及有关物质

目的 建立反相高效液相色谱法测定GCLE的含量及检查有关物质.方法 ODS-C18色谱柱(150mm×4.6mm,5μm);以乙腈:四氢呋喃:水(用1mol/L磷酸调pH3.5)(45:15:40,v/v/v)为流动相;检测波长为254nm;流速1.0ml/min;柱温25℃.结果 GCLE进样浓度在0.2537～1.0150mg/ml范围内,浓度与峰面积呈良好的线性关系(r=0.9998),日间精密度RSD=0.17%(n=6).结论 该方法简便、快速、准确且重现性好,可作为GCLE含量测定及有关物质控制方法.     

高效液相色谱法测定氨甲环酸乳膏中氨甲环酸的含量

目的建立HPL C法测定氨甲环酸乳膏中氨甲环酸的含量。方法供试品溶液制备条件采用正交试验优化。含量测定色谱条件采用Diamonsil C18色谱柱(250 mm×4.6 mm,5μm);流动相0.23%十二烷基硫酸钠溶液-甲醇(60∶40,v/v);检测波长220 nm;流速0.8 mL·min-1;柱温30℃;进样量20μL。结果提取溶剂为水-甲醇溶液(5∶5,v/v),80℃水浴搅拌加热4 min,冷却后定容,冰浴1.5 h,0.22μm微孔滤膜滤过。乳膏基质不影响氨甲环酸乳膏的含量测定。氨甲环酸在0.500 5⁴.040 mg·mL-1峰面积与浓度呈良好线性关系,r=0.999 0;最低检测限为0.49μg;最低定量限为1.64μg;平均回收率均>99%,RSD均<1.5%(n=3)。结论该方法准确、简便,专属性强,重现性好,可作为该制剂的质量控制方法。     

HPLC测定盐酸异丙嗪糖浆中盐酸异丙嗪的含量

目的:建立高效液相色谱法测定盐酸异丙嗪的含量.方法:以十八烷基硅烷键合硅胶(4.6mm×150 mm,5μm)为色谱柱,以0.5%三乙醇胺溶液(用磷酸调pH至2.5):乙腈(65:35 v/v)为流动相,流速为1.0 mL/min,检测波长为249mm.结果:盐酸异丙嗪在22.8～68.4μg/mL(r=0.9999)范围内浓度与峰面积呈良好的线性关系,平均回收率为99.97%,RSD为0.45%.结论:本测定方法简便、快速、准确,重复性好,可以有效控制盐酸异丙嗪糖浆的含量.     

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.