HPLC法测定盐酸莫西沙星中R-异构体含量

目的:建立HPLC法对盐酸莫西沙星S-和R-异构体进行拆分并测定其中R-异构体含量。方法:采用AD-H手性柱(DAICEL CHIRALPAK,250 mm×4.6 mm,5μm),流动相为正己烷-异丙醇-二乙胺-乙酸(85∶15∶0.2∶0.1),流速1.0 mL.min-1,柱温35℃,检测波长293 nm;进样量10μL。结果:盐酸莫西沙星异构体之间的分离度为3.4,R-异构体的线性范围为0.54～5.40μg.mL-1(r=0.9995),检测限为1.1 ng,平均回收率(n=9)为99.2%。结论:该方法操作简便,结果准确,可用于盐酸莫西沙星中R-异构体含量测定。     

HPLC法测定盐酸莫西沙星有关物质

目的 建立高效液相色谱法测定盐酸莫西沙星原料有关物质。方法 采用Inertsil Phenyl柱苯基键合硅胶(4.0 mm×250 mm,5μm)色谱柱,以四丁基硫酸氢铵缓冲液-甲醇为流动相,梯度洗脱,流速1.3 mL/min,柱温50℃,检测波长293 nm。结果 盐酸莫西沙星与15个已知杂质A～O均能良好分离。6个厂家盐酸莫西沙星样品测定结果显示,已知杂质及其他最大单个杂质含量均小于0.05%,杂质总含量小于0.06%。结论 本方法灵敏、专属性强,准确度高,可用于盐酸莫西沙星原料药有关物质测定。     

盐酸莫西沙星片剂有关物质超高效液相色谱法的建立

目的: 建立盐酸莫西沙星片剂有关物质超高效液相色谱法,提高检测效率。方法: 采用超高效液相色谱法,色谱柱为ACQUITY UPLC BEH Phenyl( 2. 1 mm × 100 mm,1. 7 μm) ; 流动相 A 为四丁基硫酸氢铵缓冲液-甲醇( 80∶ 20) ,流动相 B 为四丁基硫酸氢铵-甲醇( 20∶ 80) ; 进行梯度洗脱; 检测波长 293 nm; 流速为 0. 4 m L·min^{- 1}。结果: 建立了盐酸莫西沙星片剂有关物质的超高效液相色谱法,此方法的精密度、线性及准确度较好,线性范围为 0. 001 ～ 1 mg·m L^{- 1}。结论: 此方法分离效率高,可对盐酸莫西沙星片剂中全部杂质进行有效控制。     

线栓法致大鼠MCAO/IR模型缺血/再灌时间与发病机制研究进展

目的：建立盐酸莫西沙星氯化钠注射液有关物质检查的方法。方法采用苯基柱（4.6 mm ×150 mm,5μm）,流动相为乙腈-盐溶液（30：70）,检测波长为293 nm,流速为1.30 mL·min-1,柱温为30℃。结果莫西沙星与各已知杂质及降解产物均分离良好,系统适用性良好,杂质A、B、C、D、E线性良好。杂质B、杂质E校正因子分别为1.42、3.40。结论本方法检查盐酸莫西沙星氯化钠注射液有关物质专属性强、灵敏度高、准确可靠、重现性好。     

骨水泥链珠中莫西沙星体外洗提动力学研究

目的建立测定不同时间盐酸莫西沙星骨水泥链珠体外洗提液中莫西沙星含量的方法,研究其体外洗提动力学特征。方法采用高效液相色谱法,色谱柱为Inertsil ODS-3柱(4.6×150mm,5μm),流动相为1%三乙胺溶液(磷酸调节pH 3.8)-乙腈(83∶17),流速为1.0mL·min^-1,检测波长为296nm,柱温为40℃,进样量为10μL。结果盐酸莫西沙星在1~80μg·mL^-1范围内线性关系很好(r=1);精密度RSD<2.0%;加样回收率为98.75%~100.84%(RSD=1.21%,n=9)。盐酸莫西沙星骨水泥链珠中莫西沙星在336h内的释放总量为48mg,释放率26.7%,释放过程中T 1/2为118h,T max为24h,C max为32.92μg·mL^-1,AUC 0-t为3576μg/(mL·h),AUC 0-∞为4378μg/(mL·h),莫西沙星的体外洗提符合二室模型特征。结论该方法操作简便,重复性好,灵敏度高,可用于莫西沙星的体外测定。本研究可为盐酸莫西沙星骨水泥链珠的临床使用时长、用量及制备莫西沙星骨水泥链珠缓释制剂提供参考。     

HPLC测定盐酸莫西沙星的含量和有关物质

目的 采用HPLC法测定盐酸莫西沙星的含量及其有关物质.方法 采用Hypersil ODS2色谱柱(250 mm×4.6 mm,5μm),以10％四丁基氢氧化铵水溶液、硫酸和磷酸二氢钾的混合溶液-甲醇-乙腈为流动相,梯度洗脱,检测波长296 nm,流速1.0 mL· min-.结果 1 ～ 200 μg· mL-盐酸莫西沙星与峰面积的线性关系良好(r=0.9999),精密度试验的RSD=0.6％,重复性试验的RSD =0.6％ (n =6);平均回收率为99.4％,RSD =0.5％ (n =9).结论 所用方法具有良好的稳定性、精密度及重复性,适用于测定盐酸莫西沙星的含量及其有关物质.     

盐酸莫西沙星片在健康志愿者体内两种条件下的药动学研究

目的 研究盐酸莫西沙星片在健康志愿者体内两种条件下的药动学.方法 采用随机交叉自身对照试验设计,24名健康男性志愿者随机交叉单剂量空腹(或餐后)口服400 mg盐酸莫西沙星片.采用HPLC-UV法测定受试者血浆中莫西沙星的浓度,计算药动学参数,评价制剂在两种条件下的药动学行为.结果 空腹条件下,盐酸莫西沙星片的主要药动学参数为:Tmax =1.55 ±0.96 h,Cmax=3.45±0.88 μg·mL-1,AUC0-t=58.77±13.02 μg·mL-1·h,AUC0-∞=60.50±13.71 μg·mL-1·h;餐后条件下,盐酸莫西沙星片的主要药动学参数为:Tmax =2.66±1.48 h,Cmax=3.16±0.70 μg·mL-1,AUC0-t=57.01±9.95μg· mL-1·h,AUC0-∞=59.00± 10.60 μg·mL-1· h.结论 餐后与空腹条件相比,除了Tmax有所延迟外,其余药动学参数均无太大差别,表明食物可能会减缓盐酸莫西沙星的吸收.     

HPLC测定复方莫西沙星滴耳液中的莫西沙星和地塞米松

目的 采用HPLC法同时测定复方莫西沙星滴耳液中的盐酸莫西沙星和醋酸地塞米松.方法 采用Shim-Pack VP-C18色谱柱(150 mm×4.6 mm,5 μm),柱温30℃,流动相为磷酸盐缓冲液-甲醇(40;60,磷酸调pH3.0);流速为1.0 ml·min-1;检测波长为241 nm;进样量20μl.结果 盐酸莫西沙星0.3-2.4μg(r=0.9999,n;5)、醋酸地塞米松0.03-0.24 μg(r=0.9999,n=5)与峰面积的线性关系良好,平均回收率分别为98.73%(RSD=0.89%)、98.24%(RSD=0.75%).结论 所建方法 简便、快速、准确、重复性好,可用于复方莫西沙星滴耳液的质量控制.     

盐酸莫西沙星氯化钠注射液在Beagle犬体内的药物动力学

建立了HPLC法测定Beagle犬血浆中的莫西沙星,研究Beagle犬静脉滴注盐酸莫西沙星氯化钠注射液后的体内药动学.采用C_(18)色谱柱,0.05 mol/L磷酸盐缓冲液(含0.01 mol/L四丁基硫酸氢铵,pH 3.8)-乙腈(85:15)为流动相,检测波长295nm.莫西沙星在0.1～25.6μg/ml浓度范围内线性关系良好.Beagle犬静脉滴注盐酸莫西沙星氯化钠注射液后药动学呈二室开放模型,c_(max)13.70μg/ml,AUC_(0-∞) 117.20μg·ml~(-1)·h,t_(1/2α) 5.326 h,t_(1/2β)7.82h.     

反相高效液相色谱法测定盐酸莫西沙星氯化钠注射液的含量

目的:采用反相高效液相色谱法测定盐酸莫西沙星氯化钠注射液的含量.方法:色谱柱为DIKMA Inertsil Ph,4.6 mm～250 mm 5μm,流动相为磷酸盐缓冲液(取磷酸二氢钾1.0 g、四丁基硫酸氢铵0.5 g和磷酸3.4 g,加水溶解并稀释至1000 mL)-甲醇=72:28;检测波长293nm;流速1.3mL/min;柱温45℃;进样量10μL.结果:盐酸莫西沙星在82.12～110.35μg/mL范围内与峰面积呈良好的线性关系,r=0.9992,日间、日内RSD均小于1.5%.结论:本方法准确可靠,可用于盐酸莫西沙星氯化钠注射液的质量控制.     

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.

     

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.