固相萃取结合高效液相色谱法测定人血浆中酒石酸唑吡坦的浓度

目的:建立固相萃取结合高效液相色谱法测定人血浆中酒石酸唑吡坦浓度。方法:血样经固相萃取法提取,采用大连依利特色谱柱(Hypersil BDS C₁₈),流动相:甲醇-乙腈-水（45∶45∶110）,流速1.0ml·min^-1,柱温:35℃;检测波长:254 nm,内标法定量。结果:血浆中酒石酸唑吡坦浓度在0.511 5⁴.092 0μg·ml^-1线性关系良好,相对回收率大于90%,精密度日间、日内RSD均小于10%。结论:该测定方法简单、快速、准确、干扰小,适用于临床测定酒石酸唑吡坦药物浓度。     

HPLC法测定酒石酸唑吡坦口腔崩解片的含量

目的建立酒石酸唑吡坦口腔崩解片含量测定的反相高效液相色谱法。方法色谱柱为AlltimaC8柱(250mm×4.6mm,5μm),流动相为甲醇-0.1mol·L-1醋酸铵溶液(60∶40);流速为1.0mL·min-1;检测波长310nm。结果线性范围为20～200μg·mL-1,r=0.9999,平均回收率为99.92%,RSD=0.32%(n=15)。结论本法灵敏度高,重现性好,结果准确、可靠。     

UHPLC法测定辐射后的酒石酸唑吡坦片含量

目的建立UHPLC法测定辐射后的酒石酸唑吡坦片含量,考察不同辐射剂量对酒石酸唑吡坦片含量的影响。方法采用超高效液相色谱法,对γ射线辐射的酒石酸唑吡坦片进行含量测定。采用C₁₈柱以乙腈-甲醇-0.05 mol/L磷酸溶液(用三乙胺调节pH值至5.5)(18∶26∶56)为流动相,流速为0.7 ml/min,检测波长为254 nm。结果酒石酸唑吡坦浓度在5～80μg/ml范围内线性良好,r=0.999 6;平均加样回收率为98.2%,RSD为1.72%,重复性为0.87%。0、8、25和80 kGy辐射量下酒石酸唑吡坦含量分别为105.1%、106.4%、102.7%和105.4%。结论超高效液相色谱法分析周期短、结果准确,适用于辐射后酒石酸唑吡坦片的含量测定,辐射后酒石酸唑吡坦片含量基本保持不变。     

高效液相色谱法测定人血浆中羧甲司坦浓度

目的:建立高效液相色谱法测定人血浆中羧甲司坦浓度.方法:采用邻苯二甲醛为柱前衍生化试剂,反相高效液相色谱法检测羧甲司坦衍生物:Hypersil BDS C18柱(4.6 mm×150 mm,5 μm);流动相:甲醇-0.05 mol·L-1醋酸钠缓冲液(pH 5.9)-四氢呋喃(15:84:1);流速:1. 0 mL·min-1;进样量:5μL,使用荧光检测器检测激发波长:338 nm,发射波长:450 nm.结果:标准曲线线性、范围1.0～40.0 mg·L-1(r=0.999 9,n=6),血浆中羧甲司坦最低检测限为0.5 mg·L-1,日内RSD为0.3%～1.3%,日间RSD为0.4%～4.5%,准确度为97.9%～102.7%,羧甲司坦回收率为99.5%～103.0%.结论:该方法分离效果好,方法学结果满意,适用于人血浆中羧甲司坦的检测.     

高效液相荧光色谱法测定人血浆中唑吡坦的浓度

目的：建立测定人血浆中唑吡坦浓度的高效液相荧光色谱法。方法：血浆样品经甲醇沉淀后,以甲醇-1％醋酸液（40：60）为流动相,流速为0．3ml·min^-1,色谱柱为Agilent Zorbax C18（150mm×3mm,3．5μm）,柱温为22℃,荧光检测波长：激发波长（λex）254nm,发射波长（λem）390nm。结果：血浆内源性杂质不干扰待测物测定,唑吡坦的线性范围为2～300μg·L^-1,定量下限为2μg·L^-1,日内、日间RSD均〈5％。样品经3次冻融及再沉淀后,4℃下6h内稳定性良好。结论：该法灵敏、快速、准确,操作简便,线性范围宽,可用于唑吡坦的临床药动学研究。     

柱前衍生HPLC-FLD法测定人血浆中羧甲司坦

目的:建立血浆样品中羧甲司坦的柱前衍生 HPLC—FLD 测定法。方法:色谱柱:Agilent C_(18),(5μm,4.6 mm×150mm);柱温:30℃;流动相:0→25 min,A～B(89:11),A:40 mmol·L~(-1)磷酸二氢钠水溶液(1 mol·L~(-1)氢氧化钠调 pH 为7.8),B:甲醇-乙睛-水(45:45:10);25→32 min A 为100%;32→40 min,A—B(89:11);流速:0.8 mL·min~(-1);检测波长:激发波长338 nm,发射波长450 nm;进样量:2.0 μL,柱温30℃。结果:最低检测限为0.1018μg·mL~(-1);线性范围为0.1018～13.00μg·mL~(-1)(r=0.9999);低、中、高3种浓度日内(n=6)、日间(n=8)RSD 分别为4.0%,2.0%,0.7%和4.2%,2.6%,0.7%;3种浓度的绝对回收率分别为92.4%,97.2%,99.4%,RSD 分别为2.4%,1.3%,0.59%;相对回收率分别为96.96%,100.45%,100.35%,RSD 分别为2.91%,2.21%,0.50%。结论:本法准确、灵敏、易于操作,可用于羧甲司坦的体内分析及临床药学研究。     

石墨炉原子吸收光谱法测定酒石酸唑吡坦原料药中的痕量钯

目的:建立测定酒石酸唑吡坦原料药中痕量钯的方法。方法:采用石墨炉原子吸收光谱法,样品用1%盐酸溶液溶解后直接测定。采用横向平台石墨管,检测波长为244.79 nm,光谱带宽为0.2 nm,空心阴极灯工作电流强度为6 m A,扣背景方式为塞曼效应,测量模式为峰高,进样量为20μl。结果:钯的检测质量浓度线性范围为0~100 ng/ml(r=0.999 0);精密度、重复性试验的RSD≤2.0%;加样回收率为97.78%~103.07%,RSD=1.6%(n=9);检测限为1.48 ng/ml。结论:该方法操作简便、迅速,具有良好的精密度和准确度,可用于酒石酸唑吡坦原料药中痕量钯的测定。     

高效液相色谱法测定人血浆中西洛他唑浓度

目的:建立测定人血浆中西洛他唑浓度的高效液相色谱法.方法:西洛他唑血浆样品以2 mol·L -1 氢氧化钠-无水乙醚(1∶4)提取,以地西泮为内标.Hypersil C 18 柱( 4.6 mm×200 mm, 5 μm),流动相为乙腈-水 (45∶55),流速: 1.0 mL·min -1 ,检测波长:285 nm.结果:标准曲线线性范围 20.0 ～ 1 200.0 μg·L -1 (r= 0.999 9 ).血浆中西洛他唑最低检测限为10 μg·L -1 .平均提取回收率为( 81.52 ± 3.81 )%,平均方法回收率( 97.4 ± 4.5 )%, 日内及日间RSD均<11%.结论:所建立的HPLC方法灵敏、专一、准确、精密,简便,适用于西洛他唑的药动学研究及治疗药物浓度监测.     

HPLC法检测中成药及保健品中非法添加的10种镇静催眠类药物

目的应用HPLC法建立改善睡眠类中成药及保健品中可能添加的酒石酸唑吡坦、褪黑激素、马来酸咪达唑仑、苯巴比妥、奥沙西泮、阿普唑仑、硝西泮、艾司唑仑、氯硝西泮和地西泮的检查方法。方法采用Alltima C_(18)色谱柱(150 mm×4.6 mm,5μm);流动相为乙腈-0.01 mol·L~(-1)磷酸二氢铵溶液(磷酸调节至pH值为2.7)(35∶65);流速:0.5 mL·min~(-1);检测波长:220 nm。结果 10种镇静催眠类化学药物能在该色谱条件下得到分离和鉴定,从8批样品中检出1批非法添加化学药物。结论该方法简便、快速、准确,可用于中成药及保健品中非法添加镇静催眠类化学药物的检测。     

SPE-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方法.方法:采用固相萃取(SPE)血浆中头孢吡肟.色谱柱为大连依利特Hypersil BDS C18,流动相为甲醇-磷酸盐缓冲液(20:80),柱温为30℃,流速为1 ml·min-1,检测波长为257 nm,进样量20 μl.结果:头孢吡肟检测浓度线性范围为1.0～200 mg·L-1(r＝0.999 9);最低检测限为1 mg·L-1;低、中、高3种浓度头孢吡肟的方法回收率分别为118.0%,97.0%,95.0%,日内RSD分别为1.7%,3.6%,2.1%,日间RSD分别为8.2%,4.9%,2.6%.结论:该方法简便、灵敏度高,适用于测定人血浆中头孢吡肟的含量.     

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.