HPLC-MS(TOF)法测定人血浆中多奈哌齐的浓度

目的建立测定人血浆中多奈哌齐的HPLC-MS(TOF)法。方法血浆中加入内标氯雷他定后经碱化以异丙醇-正己烷(3∶97)提取血浆样品,用LC/MS(TOF)联用技术,以电喷雾(ESI)作为接口技术,选择多奈哌齐的准分子离子(［M+H］⁺,m/z 380)和内标氯雷他定的准分子离子(［M+H］⁺,m/z 383)作为测定离子,测定人血浆中多奈哌齐的浓度。结果多奈哌齐的回归方程:As/Ai=0.0137+0.1056C,r=0.9998;线性范围为0.1～15 μg·L^-1,定量限为0.1 μg·L^-1,方法回收率和提取回收率均大于90%。结论该测定方法灵敏度高、专属性好、快速,可满足人体内药代动力学研究要求。     

环维黄杨星D延长大鼠心室肌细胞APD作用的分子机制研究

目的　研究环维黄杨星D对分离的大鼠心室肌细胞内向整流钾电流 (IK1 )、瞬时外向钾电流 (Ito)、L 型钙电流(ICa L)和动作电位时程 (APD)的影响。方法　采用全细胞膜片钳技术记录大鼠心室肌细胞IK1 、Ito、ICa L 和APD。结果　 1和10 μmol·L- 1 环维黄杨星D明显延长分离大鼠心室肌细胞APD50 和APD90 ,10 μmol·L- 1 可明显降低静息膜电位 (RP)。环维黄杨星D对IK1 内向电流和外向电流均有明显抑制作用 ,当指令电压为 - 10 0mV时 ,1和 10 μmol·L- 1 环维黄杨星D分别使IK1 电流密度从给药前的 ( - 8.0± 1.1)pA pF降至 ( - 4 .1± 0 .7)pA pF和 ( - 3.4± 0 .8)pA pF ;当指令电压 - 30mV时 ,分别使IK1 电流密度从 ( 1.10± 0 .2 4 )pA pF降至 ( 0 .6 1± 0 .18)pA pF和 ( 0 .36± 0 .11)pA pF ;在钳制电位从 0到 + 6 0mV之间 ,环维黄杨星D明显抑制Ito,当指令电压 4 0mV时 ,1和 10 μmol·L- 1 环维黄杨星D分别使Ito电流密度从给药前的 ( 8.9± 2 .0 )pA pF降至 ( 5 .5± 1.2 )pA pF和 ( 4 .9± 0 .9)pA pF。环维黄杨星D浓度依赖性抑制ICa L,在指令电压为 10mV时 ,1和 10 μmol·L- 1 分别使ICa L电流密度从给药前的 ( - 9.9± 1.8)pA pF降至 ( - 6 .4± 1.4 )pA pF和 ( - 4 .2± 0 .6 )pA pF。结论　环     

大鼠经皮给药血浆中多奈哌齐浓度的UPLC-MS/MS法测定

建立了超高效液相色谱-串联质谱法测定大鼠血浆中的多奈哌齐.以氯雷他定为内标,液-液萃取处理血浆样品,采用ESI源正离子模式、多反应监测进行定量分析.监测离子对为m/z 380.3→m/z 243.2(多奈哌齐)和m/z 383.1→m/z337.1(氯雷他定).多奈哌齐在0.5～200 ng/ml范围内线性关系良好,方法回收率为94.1％～106.8％,日内、日间RSD均小于10％.     

高效液相色谱-串联质谱法研究环维黄杨星D分散片的生物利用度

目的建立人血浆中环维黄杨星D的测定方法,评价环维黄杨星D分散片与普通片剂在中国健康成年男性志愿者中的生物等效性。方法以左羟丙哌嗪为内标,血浆样品经氯仿萃取,Hyperity C18柱(150 mm×2.1 mm,5μm)分离后,采用高效液相色谱-串联质谱法检测。18名健康男性志愿者采用双周期随机交叉试验设计,分别单剂量口服环维黄杨星D分散片与普通片剂2 mg。结果环维黄杨星D与内标分离度好,内源性杂质不干扰测定,质量浓度在10～320 pg/mL(r=0.996 9)与峰面积比的线性关系良好,定量下限为10 pg/mL,萃取回收率为82.66%～89.58%(n=5),日内RSD为4.17%～9.96%(n=5),日间RSD为5.21%～10.31%(n=15)。单次服用2 mg环维黄杨星D分散片和普通片剂后的0～144 h药时曲线下面积(AUC0～144)分别为(5679.83±1548.21)pg.h/mL和(5 243.65±1 317.39)pg.h/mL,0～∞药时曲线下面积(AUC0～∞)分别为(7 464.21±2 128.08)pg.h/mL和(7 021.43±2 076.12)pg.h/mL,峰浓度(Cmax)分别为(202.81±43.30)pg/mL和(222.10±50.90)pg/mL,达峰时间(tmax)分别为(5.76±1.93)h和(5.22±1.03)h,半衰期(t1/2)分别为(54.67±12.43)h和(50.66±13.63)h。与普通片剂相比,环维黄杨星D分散片的相对生物利用度为(100.5±10.1)%。结论该方法准确度高、灵敏度好,可用于环维黄杨星D人体内过程研究。两种制剂为生物等效制剂。     

高效液相-质谱法联用测定大鼠体内去甲基斑蝥素血药浓度

目的:建立大鼠体内去甲基斑蝥素的 HPLC-MS 分析方法。方法:选用烟尿酸为内标,血浆样品经乙腈沉淀蛋白处理。色谱条件为 Hypersil SAX 阴离子交换色谱柱(4.6mm×250mm,5μm),甲醇-水(25∶75,含2.5%甲酸)为流动相,流速0.5mL·min~(-1),采用 HPLC-MS检测系统,AP-ESI 负离子模式,质谱检测参数如下:AP-ESI 负离子模式;雾化压力276kPa;温度350℃;保护气流量8 L·min~(-1);毛细管电压3500V;裂解电压为90V(NCTD)和120V(内标);SIM 检测,NCTD m/z185(M+H_2O-H)、烟尿酸m/z 179(M-H)。结果:血浆中去甲基斑蝥素检测方法的线性范围为0.2-20μg·mL~(-1),最低检测限可达2ng·mL~(-1)。血浆中去甲基斑蝥素的平均回收率为96.7%-100.3%,日内、日间 RSD 均小于8%。结论:本法灵敏、准确、选择性高,可用于去甲基斑蝥素的药代动力学研究。     

灌流液改性剂对环维黄杨星D微透析探针回收率的影响研究

目的考察灌流改性剂对环维黄杨星D微透析探针回收率的影响,验证使用改性灌流液条件下微透析探针体外相对回收率与相对损失率的一致性,为体内微透析研究提供实验依据。方法采用高效液相色谱法测定灌流液中环维黄杨星D含量,计算不同改性灌流液条件下微透析探针的体外相对回收率,优选合适的改性剂种类与用量,再分别采用增量法与减量法计算不同药物浓度水平下探针体外相对回收率与相对损失率,比较两者结果的一致性。结果常规灌流条件下,乙醇作为灌流液改性剂对环维黄杨星D相对回收率提高较多,优选灌流液配比为30%乙醇-林格氏液。在2.53~10.12μg·mL~(-1)内环维黄杨星D体外相对回收率和相对损失率具有高度的一致性。结论选择合适的灌流液改性剂可显著提高微透析探针相对回收率水平,对于同一根微透析探针环维黄杨星D体外相对回收率与外周液药物浓度无关,探针回收率可通过药物透过半透膜时的流失量来间接计算,结果较好地证明反透析法适合于环维黄杨星D微透析采样。     

LC／MS／MS测定大鼠血浆中普萘洛尔及其代谢物4-羟普萘洛尔、N-去异丙基普萘洛尔的浓度

目的:用高效液相色谱-质谱联用方法同时测定大鼠血浆中普萘洛尔及其代谢物4-羟普萘洛尔、N-去异丙基普萘洛尔的浓度。方法:大鼠血浆用乙醚萃取法处理后,采用 LC/MS/MS 方法,测定大鼠血浆中普萘洛尔及其代谢物4-羟普萘洛尔、N-去异丙基普萘洛尔的浓度。HPLC 条件:大连依利特 Hypersil BDS C_(18)柱(2.1 mm×50 mm,3μm),流动相:水(含0.1%甲酸)-乙腈(39:61,v/v),柱温:12℃,流速:200 μL·min~(-1),进样量:10 μL;质谱检测参数为电喷雾电离源(ESI);喷雾电压:3500 V;碰撞压力:0.1333 Pa;源内碰撞诱导电压:普萘洛尔,10 V;4-羟普萘洛尔,15 V;N-去异丙基普萘洛尔,15 V;扫描时间:0.3 s;检测离子:普萘洛尔 m/z 260[M H]~ ;4-羟普萘洛尔 m/z 276[M H]~ ;N-去异丙基普萘洛尔218[M H]~ 。结果:普萘洛尔线性范围2—1000 ng·mL~(-1),最低定量限为2 ng·mL~(-1)。4-羟普萘洛尔和 N-去异丙基普萘洛尔的线性范围1～200 ng·mL~(-1),最低定量限为1 ng·mL~(-1)。普萘洛尔的萃取回收率在90%以上,4-羟普萘洛尔和 N-去异丙基普萘洛尔的萃取回收率均为50%以上,日内、日间 RSD 皆小于15%。结论:适用于测定大鼠血浆中普萘洛尔及其代谢物4-羟普萘洛尔、N-去异丙基普萘洛尔的浓度及药动学的研究。     

国产与进口盐酸多奈哌齐片在健康人体的生物等效性

目的 研究国产与进口盐酸多奈哌齐片在健康人体的生物等效性.方法 20名男性健康志愿者随机交叉给药,分别单剂量口服国产(受试制剂)与进口盐酸多奈哌齐片(参比制剂),用高效液相飞行时间质谱(HPLC/TOF/MS)联用技术,测定人血浆中多奈哌齐的浓度,计算2者的药代动力学参数及相对生物利用度,并评价2制剂的生物等效性.结果 口服国产及进口盐酸多奈哌齐片5mg的主要药代动力学参数:t_(1/2)分别为(62.56±9.76),(65.70±12.80)h;t_(max)分别为(3.15±0.67),(3.10±0.55)h;C_(max)分别为(10.42±2.52),(10.06±2.02)ng·mL~(-1);AUC_(0-192)分别为(489.37±154.32),(484.76±150.13)ng·h·mL<-1>;AUC_(0-∞)分别为(566.52±193.84),(564.38±176.10)ng·h·mL~(-1).用AUC_(0-192)、AUC_(0-∞)估算多奈哌齐供试片的相对生物利用度分别为(100.7±9.2)%,(99.2 ±11.9)%.结论 2种盐酸多奈哌齐片为生物等效制剂.     

HPLC-MS法测定人血浆中克拉霉素含量的方法学研究

目的:建立人血浆中克拉霉素测定的 HPLC-MS 法。方法:血浆经1mol·L~(-1)氢氧化钠溶液碱化后,用乙醚提取。采用 Zorbax SB-C_(18)(150mm×2.1 mm,5μm)分析柱,以乙腈-水-冰醋酸(60:40:0.05)为流动相,流速为0.4 mL·min~(-1);用HPLC-ESI~+-MS 法,选择性离子检测方法。质谱检测参数如下:干燥气流速13 L·min~(-1),干燥气温度350℃,雾化气压207kPa,毛细管电压3000 V,碎片电压150 V。选择检测的离子为 m/z 748.5(克拉霉素),m/z 837.5(罗红霉素)。结果:血浆中克拉霉素检测方法的线性范围为0.01～10μg·mL~(-1),最低检测限可达1.1 ng·mL~(-1)。血浆中克拉霉素的方法回收率为92.7%～99.4%,日内 RSD<5.1%,日间 RSD<3.6%。结论:本法灵敏,准确,可用于克拉霉素的药代动力学研究。     

HPLC-MS／ESI法同时测定人血浆中盐酸特拉唑嗪盐酸哌唑嗪和甲磺酸多沙唑嗪

目的:建立同时测定血浆中盐酸特拉唑嗪、盐酸哌唑嗪和甲磺酸多沙唑嗪的 HPLC-MS/ESI 方法。方法:血浆样品0.5mL,加入10 ng·mL~(-1)二盐酸氟哌噻吨内标液50 μL,经饱和碳酸钠200 μL碱化和1.25 mL 正已烷-叔丁基甲醚(1:1)萃取;以Hypersil GOLD C_(18)柱(100 mm×2.1 mm,5 μm)为固定相,20 mmol·L~(-1)醋酸铵(0.05%甲酸,pH 4.2)-乙腈-甲醇为流动相,梯度洗脱分离,流速为0.2 mL·min~(-1);采用 HPLC-MS,选择离子检测(SIM)法测定盐酸特拉唑嗪([M H]~ ,m/z 388)、盐酸哌唑嗪([M H]~ ,m/z 384)、盐酸多沙唑嗪([M H]~ ,m/z 452和内标氟哌噻吨([M H]~ ,m/z 435)的血药浓度。结果:线性范围为1～100 ng·mL~(-1),r>0.9930(n=7);萃取回收率大于83.0%;方法回收率大于97.0%;日内、日间精密度 RSD 均小于10.0%。结论:该方法灵敏、专属、快速,适用于3种药物的血药浓度监测,以及药代动力学和生物等效性的研究。     

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.     

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.     

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.