HPLC法测定人血浆中拉莫三嗪的浓度及其影响因素研究

目的:建立测定人血浆中拉莫三嗪(LTG)浓度的方法,分析LTG血药浓度的相关影响因素。方法:血浆样品以甲醇处理后采用高效液相色谱(HPLC)法进行测定,其中内标为氯霉素,流动相为乙腈-磷酸盐缓冲液(30∶70),色谱柱为Luna C18,流速为1ml/min,检测波长为306 nm。对收集的病例进行分组,应用逐步回归法分析影响LTG血药浓度的各类因素;应用相关分析法分析不同组别中的影响因素。结果:拉莫三嗪的血药浓度在0.5²0.0μg/ml范围内线性关系良好(r=0.999 5),最低检测限为0.5μg/ml;低、中、高3种质量浓度的平均方法回收率分别为(94.39±1.57)%、(95.57±2.22)%、(91.81±2.11)%;LTG血药浓度与LTG给药剂量、联用丙戊酸(VPA)呈正相关(r分别为0.641 7、2.568 0,P<0.05),与联用苯巴比妥(PB)呈负相关(r=-2.048 2,P<0.05);性别、年龄及体质量与其不存在显著的相关关系(P>0.05)。结论:本试验建立的HPLC法操作简便、快捷、回收率高、精密度好,适用于临床上常规监测LTG的血药浓度;LTG血药浓度可受LTG给药剂量、联合应用VPA及PB等因素的影响,因此在临床有必要开展其血药浓度监测,实行个体化给药。     

HPLC法测定氯霉素滴眼液在兔眼房水中的质量浓度

目的:测定氯霉素滴眼液在兔眼房水中的质量浓度。方法:在6只兔眼结膜囊内滴入氯霉素滴眼液100μl,于滴眼后5、15、30、60、120、180 min取眼房水,加甲醇后涡旋、离心,高效液相色谱法测定上清液中氯霉素质量浓度。色谱柱为Hypersil ODS C18,流动相为甲醇-0.34%磷酸二氢钾水溶液(55∶45),检测波长为273 nm,流速为1.0 ml/min,柱温为30℃,进样量为20μl。结果:氯霉素检测质量浓度的线性范围为0.125~4μg/ml(r=0.998 6,n=6),方法回收率为91.28%~98.35%、提取回收率为88.89%~96.92%(n=3),日内RSD为2.98%、日间RSD为3.34%(n=5);各时间点眼房水样品中氯霉素质量浓度分别为0、(0.331±0.041)、(0.251±0.049)、(0.133±0.052)、(0.068±0.042)、(0.035±0.043)μg/ml。结论:本方法灵敏、结果准确,可用于兔眼房水中氯霉素质量浓度的测定。     

高效液相色谱法测定氯霉素搽剂的含量

目的:建立氟霉素搽剂中氯霉素的含量测定方法。方法:采用高效液相色谱法。色谱柱:Nova-Pak C_(18)柱(150×3.9mm,4um);流动相:0.05mol/L 磷酸二氢钾溶液-甲醇-乙腈(80:40:15);流速:1ml/min;检测波长:278nm;进样量:20μl。采用外标法测定含量。结果:本色谱条件下空白辅料不干扰主峰,氯霉素在0.5～5.0μg/ml 的浓度范围内,峰面积与进样量呈良好的线性关系(r=0.9999),含量测定的回收率为99.3%～100.6%,RSD 为0.58%。结论:该方法专属性强,操作方便,结果准确,重现性好。     

反相高效液相色谱法测定氟脲苷的血药浓度

目的:建立人血清中氟脲苷的HPLC测定方法。方法:待测血清40μl,加入10%高氯酸50μl作为沉淀试剂,提取两次,取上清液进样分析;色谱柱Shim-pack VP-ODS;流动相甲醇-水(14∶86);流速1 ml/min;检测波长268 nm。结果:在0.2~20 mg/L的范围内浓度与峰面积呈良好的线性关系(r=0.999 7),低、中、高三个浓度质控样品RSD在0.92%~10.92%之间,方法回收率为102.61%~114.13%,最低检测限为0.2 mg/L。结论:本方法灵敏度高,操作简单易行,为测定人血浆中氟脲苷的含量奠定了方法学基础。     

用HPLC法测定人血浆中头孢吡肟的浓度

目的:建立测定人血浆中头孢吡肟浓度的HPLC法。方法:色谱柱为Kromasil C_(18)柱(250 mm×4．6 mm, 5μm),流动相为甲醇-乙腈-水(5:4:91),流速1．0 mL/min,检测波长254 nm。以对乙酰氨基酚为内标,血浆样品用高氯酸沉淀蛋白质后取上清液进样分析。结果:头孢毗肟峰面积与血药浓度在1．0～200．0μg/mL范围内线性关系良好(r=0．9999)。日内RSD＜6％(n=5),日间RSD＜10％(n=5)。低、中、高3种浓度(2．0、50．0、150．0μg/mL)的方法回收率分别为(111．33±2．36)％、(100．95±0．51)％和(98．50±0．91)％,提取回收率分别为(104．21±2．15)％、(96．67±0．49)％和(94．72±0．87)％。结论:本方法简便、快速、准确、精密度好,可用于头孢吡肟的临床药动学研究。     

石丹颗粒的药动学研究

目的 考察石丹颗粒中的指标性成分在大鼠体内的药动学特征,建立LC-MS/MS法同时测定大鼠血浆中毛蕊异黄酮葡萄糖苷、迷迭香酸、甘草苷的血药浓度.方法以淫羊藿苷为内标,血浆样品乙腈沉淀后,经LC-MS/MS分离分析,采用Agilent ZORBAX SB-C18色谱柱(250mm×4.6mm,5μm);流动相为A乙腈,B:0.1%的甲酸水溶液,梯度洗脱:0~10min,A-B(12∶88)~A-B(68∶32);10~11min,A-B(68∶32)~A-B(12∶88);11~15min,A-B(12∶88)~A-B(12∶KG-*3/588);流速:1mL·min-1;采用电喷雾离子源(ESI);以离子监测(SIR)扫描方式对正负离子进行监测.结果根据药动学参数得到,毛蕊异黄酮葡萄糖苷达峰时间为32.5min,迷迭香酸的达峰时间在25min,甘草苷的达峰时间为32.5min.3种成分的半衰期分别为:140min、98min、762min.结论 该方法准确、灵敏、稳定性好、回收率高,适用于石丹颗粒药动学的研究.     

法莫替丁分散片的相对生物利用度研究

目的:研究法莫替丁分散片的相对生物利用度。方法:采用固相提取的方法对血清样品进行处理,用HPLC法对 处理样品进行测定,对法莫替丁分散片在10例健康男性志愿者体内的药动学和相时生物利用度进行研究。结果:达峰时间 (Tmax)为2.50±0.24h;峰浓度(Cmax)为129.07±12.98ng/ml;消除半衰期(T_(1/2β))为1.84±0.17h;药时曲线下面积(AUC) 为747.77±84.31ng·h·ml~(-1)。相对于普通片剂的生物利用废为96.26％。结论:法莫替丁分散片与普通片剂具有生物等效 性。     

高效液相色谱法测定氟尿嘧啶在人体内的血药浓度

目的:建立血清中氟尿嘧啶浓度的HPLC测定方法。方法:血清经处理后,采用Nova-Pak C_(18)柱,流动相为甲醇-0.3％乙酸溶度(2:98),检测波长266 nm。结果:氟尿嘧啶浓度在0.226～36.16μg·ml~(-1)范围内与峰面积呈良好的线性关系,血清中药物最低检测浓度为0.028 25 μg·ml~(-1);高中低3种浓度的日内 RSD(n=5)分别为2.2％,2.4％和3.5％,方法回收率为99.8％,107.5％和91.7％。结论:本方法灵敏度高,操作简便易行,结果准确可靠,能满足氟尿嘧啶血药浓度的测定。     

HPLC 法测定复方氯甲霜中氯霉素及甲硝唑的含量

目的 对复方氯甲霜的质量标准进行再提高研究。方法 色谱柱为AgiLent XDB-C18(150mm×4.6mm,5um);流速为1ml/min;柱温为30℃;进样量为10ul;氯霉素的流动相为甲醇-庚烷磺酸钠缓冲溶液(32:68);紫外检测波长为277nm;甲硝唑的流动相为甲醇-水(20:80);紫外检测波长为320nm;结果 氯霉素、甲硝唑进样量分别在5.56～111.2μg? mL_?1,26.02～260.2 μg.mL_?1浓度范围内与峰面积呈良好的线性关系,r分别为1.0000和0.9996(n=6);平均回收率分别为103.8 %,99.6 %,RSD分别为1.73 %和0.43 %(n=9)。结论 本方法简便快速、准确、重复性好,可用于该制剂中氯霉素及甲硝唑的含量测定。     

兔血浆中纳曲酮LC-MS/MS分析方法的建立及其在纳曲酮-3-O-辛酸酯药动学研究中的应用

目的建立快速灵敏的液相色谱-串联质谱法,研究纳曲酮-3-O-辛酸酯在兔体内的药动学。方法纳曲酮辛酸酯进入体内后可快速水解为纳曲酮,因此纳曲酮-3-O-辛酸酯在兔体内的药动学参数可基于纳曲酮的血浆样品浓度检测而获得。血浆样品预处理采用甲基叔丁基醚液液萃取方法,以纳洛酮为内标。采用Agilent Zorbax SB-C18(100 mm×2.1 mm,3.5μm)型色谱柱,以甲醇/0.1%甲酸水溶液(50∶50,V/V)作为流动相,流速0.2 mL·min^-1;正离子多反应监测模式:纳曲酮(m/z 342.2→324.1),内标纳洛酮(m/z 328.1→310.2);选用12只新西兰大耳白兔,分别im给予等摩尔剂量的纳曲酮和纳曲酮-3-O-辛酸酯,于给药前及给药后不同时间点取血,所得的血药浓度数据采用非房室模型计算主要药动学参数。结果血浆内源性物质均不干扰样品峰,建立的LC-MS/MS体内分析测定方法的绝对回收率>76%,线性范围为0.5~100μg·L^-1(r²>0.999)。兔im给予纳曲酮1.0 mg·kg^-1后纳曲酮的主要药动学参数为:Tmax为(6.7±2.6)min,Cmax为(681±153)μg·L^-1,T_1/2为(40.0±7.5)min,AUC0-t为(25850±4642)μg·min·L^-1,MRTtn为(43.7±6.1)min。兔im给予等摩尔剂量的纳曲酮辛酸酯1.2 mg·kg^-1后,纳曲酮的主要药动学参数为:Tmax为(240.0±120.0)min,Cmax为(61.3±10.6)μg·L^-1,T_1/2为(295.7±133.0)min,AUC0-t为(30650±6775)μg·min·L^-1,MRTtn为(406.1±5.0)min。结论本研究建立的LC-MS/MS方法灵敏度高,适用于纳曲酮-3-O-辛酸酯的药动学研究。与im等摩尔剂量的纳曲酮相比,纳曲酮-3-O-辛酸酯的达峰时间和半衰期显著延长,达峰浓度显著降低。     

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.     

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.     

Synthesis,Cytotoxicity and Antileishmanial Activity of Some N-(2-(indol-3-yl)ethyl)-7-chloroquinolin-4-amines

We report herein the condensation of 4,7-dichloroquinoline (1) with tryptamine (2) and D-tryptophan methyl ester (3) . Hydrolysis of the methyl ester adduct (5) yielded the free acid (6) . The compounds were evaluated in vitro for activity against four different species of Leishmania promastigote forms and for cytotoxic activity against Kb and Vero cells. Compound (5) showed good activity against the Leishmania species tested, while all three compounds displayed moderate activity in both Kb and Vero cells.     

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.