高效液相色谱法同时测定人血浆中单硝酸异山梨酯、阿司匹林和水杨酸

目的:建立同时测定人血浆中单硝酸异山梨酯、阿司匹林及其代谢物水杨酸浓度的高效液相色谱法。方法:以茶碱为内标,血浆经酸化后,乙酸乙酯提取,高效液相色谱质谱检测器(MSD)和二极管阵列检测器(DAD)串联在线测定血浆中单硝酸异山梨酯、阿司匹林和水杨酸的浓度;分析柱:Zorbax DB-C18(5μm,2.1 mmx150mm),保护柱:Zorbax DB-C8(5μm,2.1mm×12.5 mm),柱温30℃;流动相为A:3 mmol·L-1乙酸铵溶液(含冰乙酸0.022％),流速为0.17 mL·min-1,B:甲醇-乙腈(85:15),流速为0.03 mL·min-1。单硝酸异山梨酯和阿司匹林用高效液相-电喷雾质谱(HPLC/ESI-MS)选择离子检测,水杨酸用DAD检测。结果:血浆中单硝酸异山梨酯、阿司匹林和水杨酸线性范围分别为0.00625-1.2 μg·mL-1,0.025-1.2μg·mL-1,0.0625-12μg·mL-1;相对回收率分别为101.3％-103.0％,99.8％-119.7％,98.4％-104.0％;提取回收率均高于80％;日内、日间精密度均小于8％。结论:方法简便、快速、重现性好,可用于临床血药浓度监测和复方制剂的药代动力学和生物利用度研究。     

反相高效液相色谱法测定伪麻黄碱水杨酸盐血药浓度

目的:用反相高效液相色谱法测定伪麻黄碱水杨酸盐在兔血的药物浓度及药代动力学研究。方法:血清样品分别用硫酸铵沉淀蛋白,甲醇提取,用反相高效液相色谱法测定伪麻黄碱水杨酸盐。色谱柱:CLC-DOS 4.6 mm×150 mm,流动相:0.5％硫酸铵-甲醇(48:52),流速:0.8 mL·min~(-1),检测波长210 nm。结果:该方法回收率为99.95％～101.6％,RSD≤8.5％,在兔血中最低检测浓度1.14μg·mL~(-1)。回归方程为A=126.841C-127.976,r=0.999 3。结论:反相高效液相色谱可用于伪麻黄碱水杨酸盐测定。药代动力学参数符合静脉给药二室模型。     

HPLC法测定阿司匹林肠溶片中游离水杨酸含量

建立HPLC法测定阿司匹林肠溶片中游离水杨酸含量的方法。Diamonsil~(TM)(钻石)C_(18)为色谱柱,甲醇-水-冰醋酸(8:4:1)为流动相,检测波长302nm。水杨酸在1.58～31.66μg·ml~(-1)(r=0.99999)的浓度范围内线性关系良好;平均回收率为100.89％,RSD为1.06％(n=6)。本方法快速、准确。     

HPLC法同时测定复方单硝酸异山梨酯阿司匹林片含量

目的:建立用高效液相色谱同时测定复方单硝酸异山梨酯阿司匹林片中2种组分和主要降解产物水杨酸含量的方法。方法:采用Hypersil BDS C_(18)(250mm×4.6mm,5μm)色谱柱,流动相:0.02mol·L~(-1)磷酸二氢钾溶液-甲醇(60:40,用磷酸调节pH至2.8±0.1),流速1.0mL·min~(-1),检测波长220nm,柱温40℃,进样量10μL。结果:线性范围分别是:单硝酸异山梨酯0.0119～1.19mg·mL~(-1),r=0.9998(n=6);阿司匹林0.01～1.0mg·mL~(-1),r=0.9996(n=6);水杨酸0.01012～1.012mg·mL~(-1),r=0.9985(n=6)。平均回收率:单硝酸异山梨酯>99.0%,RSD为<1.0%;阿司匹林>99.0%,RSD为<0.9%。结论:本法分离度好,快速,简便。适用于复方制剂中3种组分的同时测定,可作为产品的质量控制方法。     

HPLC法测定益欣雪中的阿司匹林含量及水杨酸限量检测

目的建立益欣雪中阿司匹林含量测定及水杨酸限量检测的HPLC方法。方法色谱柱为shim-packCLC-ODS柱,流动相为乙腈-水(25;75)冰醋酸调pH值至3．0,流速1．omL．min^-1,检测波长为276nm(阿司匹林),300nm(水杨酸限量检测)。结果阿司匹林的平均回收率为100．4%(RSD=1．52％),重复性RSD为1．2％。水杨酸限量检测HPLC方法简单、有效、专属性高。结论方法可用于益欣雪的质量标准研究。     

RP—HPLC法测定正常人血浆中阿司匹林酯酶活性

目的:建立同时测定血浆中阿司匹林和水杨酸浓度的高效液相色谱法,采用水杨酸浓度与阿司匹林和水杨酸浓度之和的比值表示阿司匹林酯酶的活性。方法:色谱条件:采用 Phenomenex C_(18)(4.6 mm×150 mm,5μm)色谱柱,流动相为乙腈-0.072 mmol·L~(-1)磷酸(22:78,v/v),流速1.0 mL·min~(-1),检测波长228 nm,柱温30℃。测定阿司匹林和水杨酸浓度,计算水杨酸浓度与阿司匹林和水杨酸浓度之和的比值,绘制概率分布直方图。结果:100名健康人血浆阿司匹林酯酶活性呈正态性分布;33名健康女性和67名健康男性血浆中阿司匹林酯酶活性均显示呈正态性分布。结论:本方法简便、准确、快速,适合于体外血浆中阿司匹林酯酶活性测定研究。     

高效液相色谱法测定大鼠血浆中雷替曲塞浓度

目的:建立测定大鼠血浆中雷替曲塞的高效液相色谱方法。方法:血浆经甲醇沉淀蛋白后离心,上清液直接进样,HPLC- 紫外检测。色谱条件:Phenomenex Prodigy 5μODS3 100A色谱柱(5μm,0．46cm×25 cm)和Shim-pack GVP-ODS预柱。流动相为1％醋酸-甲醇-乙腈(60:25:15),流速1 mL·min-1。检测波长349 nm。结果:本法线性范围为25- 5000 ng·mL-1,最低定量限为25 ng·mL-1。血浆中雷替曲塞的绝对回收率为95．1％-105．8％,方法回收率为102．3％- 107．7％,日内RSD≤9．0％,日间RSD≤8．3％。结论:本方法适用于雷替曲塞在大鼠体内的药代动力学研究。     

HPLC同时测定阿司匹林类药物中阿司匹林的含量和游离水杨酸的限量

目的 采用HPLC法同时测定阿司匹林类药物中阿司匹林的含量和游离水杨酸的限量.方法 用1％冰乙酸的乙醇溶液处理供试品,采用Sepax GP-C18色谱柱(150 mm ×4.6 mm,5μn),0.2％ H3PO4水溶液-CH3 CN (79∶21)为流动相,流速1.0 mL·min-,柱温30℃,检测波长303 nm.结果 阿司匹林和水杨酸的线性范围分别为0.05 ～ 0.60 mg· mL-1(r=0.9993)和1.5 ～30 μg·mL-1(r =0.9999),平均加样回收率分别为97.00％ ～ 99.72％和98.25％ ～ 99.05(n =4).结论 所用方法简单、准确,可同时测定阿司匹林类药物中阿司匹林的含量和游离水杨酸的限量.     

高效液相色谱法测定复方苯甲酸乳膏中苯甲酸和水杨酸的含量

目的:建立高效液相色谱法(HPLC)测定复方苯甲酸乳膏中苯甲酸和水杨酸的含量。方法:色谱柱为Hypersil C_(18)柱(4.6nm×250mm,5μm),流动相为甲醇-水(44:56),流速0.8mL·min~(-1),检测波长为226nm。结果:苯甲酸和水杨酸分别在15.20～76.00mg·L~(-1)和7.64～38.20mg·L~(-1)范围内线性良好(r=0.9999);日内、日间RSD在0.030～4.79％,高、中、低浓度回收率在98.54％～101.20％。分析了3批样品,结果满意。结论:本方法简便,快速,准确,可作为复方苯甲酸乳膏的质量控制方法。     

高效液相色谱法分离测定阿司匹林片的含量及游离水杨酸的限度

目的:建立一种用高效液相色谱法分离检测阿司匹林和游离水杨酸的方法。方法:以HYPERSIL,BDS,C18(5μm,4.6×250mm)为固定相;乙腈-甲醇-0.01mol·L~(-1)磷酸二氢钾-三乙胺(10:50:40:0.11,磷酸调pH3.3～3.4)为流动相;检测波长280nm。结果:阿司匹林在2.0～10μg浓度范围内。水杨酸在0.06～0.3μg浓度范围内与峰面积呈线性关系。方法的平均回收率,阿司匹林为100.1％,RSD=0.65％(n=5);水杨酸为98.2％,RSD=1.28％(n=5)。结论:方法不需提取,溶解后直接进样,方便快捷,可作为质控方法。     

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.

     

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.     

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.     

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.