高效液相色谱法同时测定血清中咖啡因和氯唑沙宗的浓度

目的:建立同时测定血清中两种探针药物(咖啡因、氯唑沙宗)浓度的高效液相色谱法.方法:采用迪马C18色谱柱(250 mm×4.6 mm,5 μm);流动相:乙腈-0.02 mol·L-1 磷酸二氢钾溶液(1∶3,v/v),含0.01 mol·L-1三乙胺;流速:1.5 mL·min-1;紫外检测波长:280 nm;柱温:30℃.结果: 咖啡因在2.5～12.5 μg·mL-1、氯唑沙宗在2.5～12.5 μg·mL-1的浓度范围内线性关系良好,最低检测限分别为0.1 μg·mL-1、0.4 μg·mL-1,回收率分别为103.70%±4.36%、102.82%±4.39%.结论: 本法操作简便,灵敏度高,快速可靠,可用于血清中咖啡因和氯唑沙宗的浓度测定.     

高效液相色谱法测定人血浆中塞来昔布的浓度

目的:建立测定人血浆中塞来昔布浓度的高效液相色谱法.方法:以美国迪马公司钻石C18反相柱(250 mm×4.6mm,5μm)为色谱柱,流动相为甲醇-水(85:15),流速为0.8 mL·min-1,检测波长254 nm,以醋酸乙酯为提取剂.结果:塞来昔布高、中、低(800.0,200.0,25.0μg·L-1)3种浓度的平均回收率分别为100.15%,95.31%,92.20%,日内、日间差RSD均低于6%;分析方法的最低检测浓度为10.0μg·L-1,线性范围为25.0～1 000.0 μg·L-1.结论:该方法灵敏、准确、简单、快速,可用于临床血浓监测和药动学研究.     

HPLC法测定围手术期患儿血浆中瑞芬太尼浓度

目的:建立高效液相色谱法测定围手术期患儿血浆瑞芬太尼浓度.方法:采用Hypersil CN柱(250 mm×4.6 mm,5μm);流动相为乙腈-0.02 mol·L-1磷酸二氢钾水溶液内含三乙胺0.02%(30:70);流速1.0 ml·min-1;检测波长210nm;进样量为20 μl.结果:标准曲线在1.0～100.0 μg·L-1 内线性关系良好(r=0.999 3).最低检测浓度为1.0μg·L-1.提取回收率(76.51±0.82)%.方法回收率99.66%～102.40%.日内和日间RSD均小于15%.2μg·L-1组靶控浓度与实测浓度基本一致.结论:本方法快速、准确、灵敏、专一性好,适用于临床瑞芬太尼血药浓度检测和药动学研究.     

高效液相色谱法测定盐酸二甲双胍血药浓度

目的:建立一种快速、灵敏、准确的高效液相色谱法用于测定人血浆中盐酸二甲双胍浓度.方法:取血浆样品0.5 mL,用1.0 mL乙腈沉淀蛋白,取上清液10 μL进样,流动相为甲醇-磷酸盐(50 mmol·L-1用氢氧化钠调节pH 6.7),色谱柱为Silica柱(4.6 mm×250 mm,5 μm),紫外检测器,检测波长为233 nm.结果:盐酸二甲双胍在20～4 000 μg·L-1范围内线性关系良好,最低检测限为20μg·L-1.日内、日间精密度(RSD)小于4%.结论:该法操作简单,灵敏度高,适用于临床药动学研究.     

反相高效液相色谱法测定血浆中吗氯贝胺浓度

目的:建立人血浆中吗氯贝胺的反相高效液相色谱检测方法.方法:血浆样品在碱性条件下(pH 11.0)用二氯甲烷提取处理.色谱柱为μ-BondapakTM C18 (3.9 mm×15 0mm,10 μm),柱温37.0 ℃,流动相为乙腈-0.067 mol·L-1磷酸二氢钾溶液(1∶5,pH 2.6),流速1.0 mL·min-1,内标为甲氧氯普胺,检测波长为240 nm.结果:吗氯贝胺在40～4 000 μg·L-1范围内线性关系良好(r=0.999 9,n=8),血浆中最小检测浓度为10 μg·L-1(S/N=3),提取回收率为96.48%～100.38%,方法回收率在99.39%～103.07%之间,日内RSD≤8.14%,日间RSD≤6.25%.结论:该方法快速、准确、灵敏度高、专一性强,可用于吗氯贝胺血浆浓度监测和药动学及生物利用度研究.     

HPLC测定消毒液中苯扎溴铵

目的 建立高效液相色谱测定消毒剂中苯扎溴铵含量的方法.方法 采用Agilent XDB-C18柱(4.6 mm×150 mm,5 μm),以0.02 mol·L-1庚烷磺酸钠溶液(含0.1%三乙胺,用磷酸调节pH至3.45±0.1)-乙腈(35∶65)为流动相,检测波长262 nm,柱温30 ℃.结果 苯扎溴铵浓度在2.5～50 μg·mL-1内线性关系良好(r=0.999 9),平均回收率99.5%.结论 本方法灵敏、简便、准确.     

简单灵敏的LC-MS/MS方法检测人血浆中普伐他汀的浓度

目的:建立液质联用法测定人血浆中普伐他汀的浓度.方法:空白血浆加普伐他汀和内标,用Bond Elut C18小柱进行固相提取,然后用LC-MS/MS进行分析.采用Thermo Hypurity C18柱(150 mm×2.1mm,5 μm),流动相为乙腈-0.2%甲酸水溶液(85:15),流速0.2 mL·min-1,柱温40℃,进样量为2 μL.采用ESI正离子方式进行检测,用于定量分析的检测离子为m/z 447→327(普伐他汀钠)和m/z 482→272(瑞舒伐他汀).结果:本方法线性范围是2.52～660 μg·L-1,r2=0.994,最小检出浓度(LLOQ)为2.52 μg·L-1.绝对回收率均在70%以上,相对回收率在98%～102%之间,日内、日间RSD均<15%.结论:本方法简便、灵敏、准确,可用于普伐他汀血药浓度检测和药动学研究.     

反相高效液相色谱法测定人血浆中头孢地尼的浓度

目的:建立人血浆中头孢地尼浓度的反相高效液相色谱测定方法.方法:以甲硝唑为内标,血浆样品经三氯乙酸(TCA)沉淀蛋白处理,色谱柱为Nucleodur C18(250 mm×4.6 mm,5 μm),保护柱为自填C18柱,流动相为0.025 mol·L-1磷酸二氢铵溶液(pH 3.0)-乙腈(90.5:9.5),检测波长为286 nm,流速为1.0 ml·min-1.结果:头孢地尼的线性范围为0.05～2.00 μg·ml-1(r=0.999 8).日内精密度RSD为3.7%～5.9%,日间精密度RSD为3.5%～5.7%.绝对回收率为65.0%～72.4%.结论:该法灵敏、准确、简便,检测限低(LOQ),重现性好,可用于血浆头孢地尼浓度的测定.     

RP-HPLC法测定罗布麻和大花罗布麻不同部位中槲皮素的含量

目的 比较罗布麻和大花罗布麻叶不同部位中槲皮素的含量. 方法 采用回流法提取槲皮素;采用Hypersil BDS C18 (150 mm×4.6 mm,5 μm)色谱柱;以甲醇-1 g·L-1磷酸水溶液(50:50)为流动相;流速1.0 mL·min-1;柱温30 ℃;检测波长为360 nm. 结果 槲皮素质量浓度在6...     

HPLC法测定人血浆中盐酸二甲双胍的浓度

目的:建立HPLC法测定人血浆中的盐酸二甲双胍浓度.方法:血浆在酸性条件下以乙腈沉淀蛋白后,用二氯甲烷萃取纯化,以甲醇-5 mmol·L-1磷酸盐缓冲液(pH 6.6)(51:49,每100ml中含SDS 0.1 g)为流动相,色谱柱为Hypersil ODS C18柱(5 μm,4.6 mm×150 mm),检测波长为234 nm,柱温40℃.结果:线性范围为125～5 000 ng·ml-1,最低检测限为20ng·ml-1.低、中、高3种浓度的方法回收率分别为105.76%,93.60%和91.89%.日内、日间RSD均小于5%.结论:该法简便、准确、灵敏,可用于盐酸二甲双胍生物利用度和药物动力学研究.     

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.     

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.     

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.