LC-MS-MS方法检测人血浆中奥美沙坦的浓度

目的建立液-质联用法测定人血浆中奥美沙坦的浓度。方法用替米沙坦作内标,采用乙腈直接沉淀血浆样品,LC-MS-MS进行分析。色谱柱为Waters Xterra MS C18（2.1mm×50mm,5μm）,柱温为40℃,流动相为乙腈-0.1%甲酸（50∶50,v/v）,流速为0.3mL.min-1,进样量为10μL。ESI正离子方式进行扫描,MRM方式检测,用于定量分析的检测离子为m/z：448.27→429.7（奥美沙坦）和m/z：516.43→497.8,276.5（替米沙坦）。结果本方法线性范围是1.16-2280ng.mL-1,权重为1/w,r^2=0.999,最小检出浓度（LLOQ）为1.16ng.mL^-1。绝对回收率均在80%以上,相对回收率为85%-115%,日内、日间RSD均〈15%。结论本方法经济、简单、灵敏、快速,可用于奥美沙坦血药浓度检测和药物动力学研究。     

大鼠血浆中积雪甙浓度的HPLC/MS/MS测定

建立了HPLC／MS／MS测定大鼠血浆中的积雪甙。以柴胡皂甙D为内标，采用XTerra C18柱，流动相为O．1％乙酸和含O．1％乙酸的乙腈，梯度洗脱。质谱条件为电喷雾离子源，检测方式为多反应检测，定量分析离子为m／z981．5→493（积雪甙）和803→331（柴胡皂甙D），血浆样品采用固相萃取处理。检测限为0．5ng／ml。     

人血浆中马钱子碱的LC-MS/MS法测定

建立了LC-MS／MS法测定人血浆中马钱子碱浓度。采用C18柱，流动相为乙腈-0．2％甲酸溶液（60：40），乌头碱为内标。电喷雾离子源（ESI），正离子检测，采用多反应监测方式进行定量分析，检测离子分别为m／z395→324、263（马钱子碱），m／z646→586、526（内标）。血浆中马钱子碱浓度在4-400ng／ml范围内线性关系良好，最低定量限为4ng／ml。马钱子碱的萃取回收率为86．0％～91．0％，日内及日间RSD分别低于6％和7％。     

HPLC-MS/MS测定人体血浆中克拉霉素浓度的方法及方法学确证

目的建立测定人体血浆中克拉霉素浓度的高效液相色谱-串联质谱联法（HPLC-MS/MS）法。方法血浆样本用甲醇沉淀蛋白后,选用色谱柱Agilent-XDB-C8柱（2.1mm×150mm,5μm）,以甲醇（A相）：水（含0.1%甲酸）=85：15（V：V）的比例为流动相,流速为0.2ml/min,选用岛津（SHIMADZU）高效液相色谱系统,串联API3200型三重四极杆质谱仪,采用多重反应监测（MRM）扫描方式进行监测,电喷雾离子化源（ESI源）,正离子方式,用于定量分析的离子反应对分别为质荷比m/z748.4→m/z158.2（克拉霉素）和m/z515.3→m/z276.2（替米沙坦,内标）。结果本方法血浆中克拉霉素的线性范围为10～3000ng/ml（r〉0.99）,定量下限为10ng/ml,批内和批间相对标准偏差均〈15%,准确度（相对回收率）相对标准偏差也均〈15%。稳定性试验中,血浆中克拉霉素在方法学要求的各种贮存条件下均较稳定。结论该方法快速、灵敏、专属性强、重现性好,适用于人体内克拉霉素的药代动力学研究。     

液相色谱-串联质谱法测定人血浆中盐酸舍曲林浓度

目的：建立测定人血浆中盐酸舍曲林浓度的液相色谱-串联质谱法。方法：以替米沙坦为内标,内标法定量。流动相：乙腈-10mmol·L^-1乙酸铵-1%甲酸（70：30：0.1）;质谱采用离子喷雾离子化源,扫描方式为多重反应监测（MRM）,用于定量分析的离子反应分别为m/z306.3→m/z159.1（舍曲林）和m/z515.2→m/z276.1（替米沙坦）。结果：舍曲林和替米沙坦的保留时间分别为2.22min和2.44min;舍曲林的线性范围为0.5～50.0ng·mL^-1,r=0.9992,回归方程：Y=0.0021＋0.0217X,最低检测浓度为0.5ng·mL^-1;提取回收率在82%～90%范围内;日内相对标准差〈4%,日间精密度〈13%。结论：此法适合人体血浆盐酸舍曲林浓度的监测及生物利用度研究,结果准确、可靠。     

人血浆中辛伐他汀的HPLC-MS/MS测定

建立了HPLC-MS／MS法测定人血浆中辛伐他汀的浓度，并以24名健康志愿者进行了两种辛伐他汀片的生物等效性研究。采用C18柱，流动相为0．5％甲酸溶液和乙腈，梯度洗脱。质谱采用电喷雾离子化，定量分析离子分别为m/z482．0-441．0（辛伐他汀）和m／z468．0→427．0（洛伐他汀，内标）。辛伐他汀在0．2-50ng／ml范围内线性关系良好。方差分析和双单侧t检验表明两制剂生物等效。     

高效液相色谱串联质谱法测定人血浆中氨溴索浓度

目的：建立测定人血浆中氨溴索浓度的高效液相色谱串联质谱法,以用于氨溴索人体药动学研究。方法：以西替利嗪为内标,血浆样品经乙腈沉淀后,经HPLC—MS／MS分离-分析。采用Waters ODS C18柱（50mm×2．1mm,3．5μm）,以甲醇：5mmol·L^-1乙酸铵（72．5：27．5）为流动相,流速：0．20ml·min^-1,采用电喷雾离子源（ESI）,以多离子反应监测方式（MRM）进行正离子监测,氨溴索和内标西替利嗪的定量分析离子对分别为m／z 379．0→263．9和m／z 389．1→201．3。结果：氨溴索血浆浓度测定方法线性范围为1．99～398ng·ml^-1,r=0．9990。定量下限为1．99ng·ml^-1,方法回收率在85％～115％之间。日内和日间RSD〈15％。结论：本法灵敏、准确、可靠,适用于盐酸氨溴索人体药动学研究。     

人血浆中苦参素的HPLC-MS测定

建立了HPLC—MS法测定人血浆中苦参素浓度，并用于其胶囊的药物动力学研究。以非那雄胺为内标，采用C18柱，流动相为5mmol／L乙酸铵（含0．05％三乙胺）-甲醇（18：82，乙酸调至pH6．2）。质谱条件为电喷雾离子源，选择检测离子为m／z 265．2（苦参素）和m／z 373.3（非那雄胺）。苦参素在2．5～500ng／ml范围内线性关系良好。     

HPLC-MS-MS测定犬血浆中间尼索地平含量

目的：利用HPLC-MS-MS测定Beagle犬血浆中间尼索地平的含量，并计算药动学参数。方法利用Symmetry C18柱，20℃下，以乙腈-水（70∶30，v／v）为流动相，流速为0A．8ml／min，检测波长237nm。采用负离子多离子反应监测，用于定量分析的离子反应为m／z387．0→m／z122．0。血浆样品采用乙腈沉淀蛋白，进样质谱分析。结果方法的最低定量下限为0．25ng／ml；间尼索地平检测浓度在0．25～20ng／ml的范围内线性关系良好（r＝0．9943）。药代动力学参数：Cmax为（13．86±3．12）ng／ml，Tmax为（2．6±2．25）h，t1／2为（9．37±2．74）h，ke为（1．24±0．52）×10－3，AUC0-t为（88．46±4．79）ng·h－1·ml－1，AUC0-∞为（98．35±1．89）ng·h－1·ml－1。结论本法灵敏度高，操作方便，适合于Beagle犬血浆中间尼索地平的药动学研究。     

HPLC-MS/MS法测定大鼠血浆中金丝桃素的浓度

目的：建立HPLC-MS/MS法测定大鼠血浆中金丝桃素的浓度。方法：血浆样本加入适量内标,经乙腈直接沉淀蛋白后采用HPLC-MS/MS进行分析。色谱柱采用Ultimate C18柱（150 mm×2.1 mm,5.0μm）;流动相由乙腈-5 mmol·L^-1醋酸铵（含0.1%甲酸）（90∶10）组成,柱温35℃;流速0.5 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。金丝桃素和内标吡格列酮在负离子模式下定量分析离子对分别为m/z 503.2→m/z 405.1和m/z 355.0→m/z 41.9。结果：金丝桃素在0.1-13.2 ng·ml^-1线性关系良好（r〉0.99）,最低定量限为0.1 ng·ml^-1,提取回收率为84.19%-98.71%,日内、日间精密度均不高于18.47%。结论：该方法分析速度快、灵敏、准确,为临床进一步研究金丝桃素提供了基础。     

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.     

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.     

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.