RP-HPLC梯度洗脱法测定盐酸伊托必利的有关物质

目的:建立RP-HPLC梯度洗脱法测定盐酸伊托必利的有关物质。方法:Alltima C18柱(4.6 mm×250 mm,5μm);流动相为0.05 mol.L-1磷酸二氢钾溶液(调节pH至4.0)-乙腈进行梯度洗脱,流速1.0 mL.min-1,柱温35℃,检测波长258nm,进样量20μL。结果:本文色谱条件中盐酸伊托必利与杂质有较好分离,盐酸伊托必利浓度在1～10μg.mL-1范围内与峰面积线性关系良好(r=0.9999,n=5),最低检测限为6 ng。结论:本法简便、专属,重复性好,可用于测定盐酸伊托必利的有关物质。     

LC-MS/MS法测定人血浆中替利定和去甲替利定的质量浓度

目的:建立LC-MS/MS法测定人血浆中替利定和去甲替利定的质量浓度。方法:选用Agilent-Zorbax-Eclipse-XDB-C18色谱柱,以甲醇-1 mmol·L-1醋酸铵(75∶25)为流动相,采用正离子,多反应监测方式测定样品质量浓度。用于定量分析的离子对分别为[M+H]+m/z 274.3→m/z 155.1(替利定),[M+H]+m/z 260.2→m/z 155.1(去甲替利定)和[M+H]+m/z 284.8→m/z 192.9(地西泮)。结果:血浆样品中,替利定在0.5～250 ng·mL-1范围内线性关系良好(r=0.9936),最低定量质量浓度为0.5 ng·mL-1;去甲替利定在1～500 ng·mL-1范围线性关系良好(r=0.9948),最低定量质量浓度为1 ng·mL-1。二者日内与日间RSD均小于15%,平均回收率高,且稳定性均较好。结论:本方法简便快速、灵敏准确、特异性强,适用于盐酸替利定和去甲替利定的体内药代动力学研究。     

超高效液相色谱-串联质谱法测定人血浆中卡巴他赛与血浆蛋白的结合率

目的建立并应用超高效液相色谱-串联质谱法(UPLC-MS/MS)测定人血浆中卡巴他赛与血浆蛋白的结合率。方法以拉洛他赛为内标,样品经叔丁基甲醚液液萃取,采用ACQUITY BEH C18色谱柱(50 mm×2.1 mm,1.7μm);流动相:2 mmol·L-1醋酸铵水溶液-乙腈;流速:0.2 mL·min-1;进样量:5μL;柱温:35℃;采用ESI正离子源,定量分析离子反应分别为m/z 836.36→m/z 555.26(卡巴他赛)和m/z 832.25→m/z 551.08(内标拉洛他赛)。结合平衡透析法,测定了卡巴他赛的人血浆蛋白结合率。结果卡巴他赛浓度在5¹ 000 ng·mL-1范围内线性关系良好,定量下限为5 ng·mL-1,日内和日间精密度均小于15.0%,提取回收率为70.0%1 000 ng·mL-1范围内线性关系良好,定量下限为5 ng·mL-1,日内和日间精密度均小于15.0%,提取回收率为70.0%⁹1.4%,基质效应为87.4%91.4%,基质效应为87.4%¹00.9%,可用于卡巴他赛的血浆蛋白结合率研究。卡巴他赛在低、中、高三个浓度下的人血浆蛋白结合率为(87.8±4.0)%、(76.4±0.8)%和(73.5±6.4)%。结论本方法简单、快速、灵敏,能满足分析要求。卡巴他赛与人血浆蛋白结合率较高,与血浆蛋白结合能力在考察的浓度范围内无浓度依赖性。     

LC-MS/MS法同时测定人血浆伊曲康唑和羟基伊曲康唑浓度

目的:建立同时测定人血浆伊曲康唑和羟基伊曲康唑浓度的液相色谱-串联质谱法(LC-MS/MS)。方法:100μL血浆样品经液-液萃取后,以乙腈-水-冰醋酸(60:40:1.5)为流动相,经Neucleosil ODS柱(50 mm×2.0 mm,5μm)分离,采用电喷雾电离源,以多反应监测(MRM)方式进行正离子检测。用于定量分析的离子分别为m/z 705→m/z 392(伊曲康唑),m/z 721→m/z 408(羟基伊曲康唑)和m/z 383→m/z 337(内标氯雷他定)。结果:测定血浆伊曲康唑和羟基伊曲康唑的线性范围分别为:10～2 500 ng.mL-1和20～4 000ng.mL-1,最低定量限(LLOQ)分别为:10和20 ng.mL-1。日内、日间精密度(RSD)均<15.0%,准确度(RE)在±7.8%以内。结论:该方法分析时间短、灵敏度高、专属性强,适用于伊曲康唑和羟基伊曲康唑的药动学研究。     

高效液相-质谱串联法测定大鼠血浆中辛伐他汀及辛伐他汀酸的浓度

目的:建立HPLC-MS法测定大鼠血浆中辛伐他汀及其代谢物辛伐他汀酸的浓度。方法:血浆样本加入适量内标和醋酸铵缓冲液,以甲基叔丁基醚萃取后采用LC-MS进行分析。色谱柱采用Inertsil ODS-3柱(150 mm×2.1 mm,5.0μm);流动相由乙腈-2.5 mmol.L-1醋酸铵(含0.1%甲酸)(75∶25)组成,柱温35°C;流速0.3 mL.min-1;采用电喷雾离子源(ESI),以多反应监测方式(MRM)进行定量分析。辛伐他汀和内标洛伐他汀在正离子模式下定量分析离子对分别为m/z 419.2→m/z199.2和m/z 405.2→m/z 199.2;辛伐他汀酸和内标洛伐他汀酸在负离子模式下定量分析离子对分别为m/z 435.2→m/z319.2和m/z 421.4→m/z 319.2。结果:辛伐他汀和辛伐他汀酸在5.0～6 400 ng.mL-1内线性关系良好(r>0.999),最低定量限为0.1 ng.mL-1,提取回收率为87.91%～99.77%,日内、日间精密度均不高于8.95%。结论:该方法分析速度快、灵敏、准确,为临床进一步研究辛伐他汀提供了基础。     

HPLC-MS/MS法测定人血浆中尼古丁浓度

目的建立简单、快速且灵敏的液质联用法检测人血浆中尼古丁的浓度。方法 血浆样品经二氯甲烷萃取后,采用Thermo Hypurity CN柱(2.1mm×150mm,5μm)分离,以乙腈-20mmol.L-1甲酸铵(50∶50,v/v)为流动相,流速为0.30mL·min-1。采用电喷雾离子源(ESI源)正离子多反应监测(MRM)扫描分析,尼古丁和d-4-尼古丁的离子选择通道分别为:m/z163→130和m/z 167→133.9。结果尼古丁的线性范围为0.597～76.48ng·mL-1,最低检测浓度为0.597ng·mL-1,平均提取回收率为70.7%～86.8%,日内和日间变异均<15%。结论本方法简单、灵敏、快速、重现性好,适用于尼古丁的人体临床药物代谢动力学及生物等效性研究。     

人血浆中盐酸伊托必利含量测定及药物动力学研究

目的:建立一种测定人血浆中盐酸伊托必利血药浓度的反相高效液相色谱法,并用该法研究盐酸伊托必利颗粒的人体药物动力学.方法:采用外标法,血样经乙醚-氢氧化钠混合溶剂提取后,以nucleosil C18 250 mm×4.6 mm,5 μm色谱柱为固定相,乙腈-磷酸二氢钾为流动相,在257 nm波长处定量检测.结果:血药浓度在10.0～1 600.0 ng·ml-1范围内线性关系良好,最低检测浓度为10.0 ng·ml-1.日内、日间精密度RSD(%)均小于7%,低、中、高浓度(20,100,800ng·ml-1)的相对回收率分别为106.3%,104.6%,102.8%.用该法检测了20名健康受试者服用盐酸伊托必利颗粒后不同时间的血药浓度变化,并计算了有关药物动力学参数.结论:此方法简便、快速、精确,适用于伊托必利的血药浓度检测和药物动力学研究.     

LC-MS/MS法测定健康人血浆中的特比萘芬

目的:建立一种快速测定人血浆中特比萘芬血药浓度的LC-MS/MS法.方法:采用C18柱(4.6 mm×150 mm,5μm),柱温30℃,流动相为甲醇-水(含20 mmol·L-1乙酸铵)(95∶5),流速1.0 mL· min-1;气动辅助电喷雾离子化(ESI),正离子模式多反应离子检测(MRM);特比萘芬和内标(酮康唑)分别为:m/z 292.00→141.10,m/z 530.95→82.10.结果:特比萘芬在10.3～2054 ng·mL-1范围内线性关系良好(r=0.9978),定量下限10.27 ng·mL-1.特比萘芬低、中、高三个浓度批内及批间相对标准偏差、准确度、绝对回收率均符合方法学要求,无显著基质效应.结论:该方法专属性强、分析周期短,适合于临床上特比萘芬血浆含量的测定.     

高效液相色谱串联质谱法测定人体血浆中阿那曲唑的浓度

目的建立液质联用法来检测人体血浆中阿那曲唑的浓度。方法血浆样品经MTBE萃取后,选用来曲唑为内标。色谱柱为Thermo Hypurity C18柱(2.1 mm×150 mm,5μm);流动相为乙腈-0.1%甲酸(60∶40);流速为0.20 mL.min-1;采用ESI+MRM进行离子方式监测;源电压:3.6 kV;源温度:100℃;阿那曲唑和来曲唑的离子选择通道分别为:m/z294.69→225.41,286.25→217.60。结果阿那曲唑的线性范围为0.214~214 ng.mL-1,最低检测浓度为0.214 ng.mL-1,方法回收率在80%~120%,日内、日间RSD均<15%。结论本方法简单、灵敏,可以准确检测人体血浆中阿那曲唑的浓度。     

LC-MS/MS方法同时检测人血浆中异烟肼、乙胺丁醇和吡嗪酰胺的浓度

目的:建立同时检测人血浆中3种抗结核药物异烟肼、乙胺丁醇和吡嗪酰胺浓度的LC-MS/MS方法,用于肺结核患者及临床试验中三药血药浓度的测定。方法:以对乙酰氨基酚为内标,血浆样品经乙腈沉淀蛋白等处理后检测。采用AgilentZORBAX SB-Aq色谱柱(2.1 mm×100 mm,3.5μm)为分析柱,ZORBAX SB-Aq柱(2.1 mm×12.5 mm,5μm)为保护柱,以乙腈-5 mmol·L-1甲酸铵水溶液(含0.1%甲酸)(8:92,v/v)为流动相,使用电喷雾离子源(ESI),以正离子多反应监测(MRM)方式进行检测,异烟肼m/z 138.2→121.0,乙胺丁醇m/z 205.2→116.1,吡嗪酰胺m/z 124.1→81.1,对乙酰氨基酚m/z152.0→110.0。分析时间为5 min。结果:血浆中内源性物质对测定无干扰,异烟肼线性范围为0.1～6.0μg.mL-1,定量下限(LLOQ)为0.1μg.mL-1,乙胺丁醇线性范围为0.1～5.0μg.mL-1,定量下限(LLOQ)为0.1μg.mL-1,吡嗪酰胺线性范围为1.0～50.0μg.mL-1,定量下限(LLOQ)为1.0μg.mL-1。日内、日间精密度(RSD)均小于10%,准确率为90.4%～108.7%。结论:本方法特异性强,灵敏度高,测定结果可靠,适用于临床血浆样品的高通量分析。     

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.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

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.     

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.