高效液相色谱法测定血浆和尿中头孢唑肟浓度

本文建立了高效液相色谱法测定人血浆和尿中头孢唑肟浓度。血样经高氯酸沉淀蛋白后,直接进样测定;尿样稀释后直接进样测定。固定相为C_(18),5μm颗粒,流动相为乙腈:水:磷酸:二乙胺—1:9:0.013:0.017(v/v)。检测波长为UV254nm(血浆)和290nm(尿),采用内标法定量。方法的线性范围分别为1～160μg/ml(血浆)和10～1600μg/ml(尿),检测限为2ng,平均回收率分别为99.0±1.0%(血浆)和100.3±0.6%(尿)。日内及日间CV%均小于5%。     

大鼠血浆中环丙沙星的HPLC荧光分析检测法及其体内药物动力学研究

建立测定大鼠血浆中环丙沙星的RP HPLC荧光检测法和研究其体内的药物动力学。以格帕沙星为内标 ,血浆样品经乙腈沉淀蛋白 ,取上清夜进行HPLC检测。流动相为 0 0 5mol/L磷酸盐缓冲液( pH3 0 )—乙腈—甲醇 ( 77∶13∶10 ,v/v/v) ,荧光检测 ,λEX=2 76nm ,λEM=448nm。血浆样品在 0 0 0 2 5～ 0 5μg/ml范围内线性关系良好 ,平均提取回收率为 97 1% ,日间和日内精密度RSD均小于 8 0 % ,最低检测限达到 1 0ng/ml。环丙沙星在大鼠体内的过程符合双隔室开放型一级吸收动力学模型、药动学参数分别为 :T1/2(ka) =0 44h ,T1/2 (α) =0 92h ,T1/2 ( β) =5 6 6h ,Tmax=1 0 4h ,Cmax=0 35 μg/ml,AUC =1 86h·μg/ml。     

高效液相色谱法测定复方利福平片中利福平、异烟肼及吡嗪酰胺的含量

用HPLC法测定复方利福平片中利福平、异烟肼及吡嗪酰胺的含量。方法 :采用SpherisorbCN(2 50mm× 4 6mm ,5μm)色谱柱 ,流动相采用 0 0 1mol/L庚烷磺酸钠溶液 (pH2 2 )—乙腈 (44∶56,v/v) ,流速为 2 0ml/min,检测波长为 2 54nm。结果 :利福平在 71 76～ 1 66 40 μg/ml、异烟肼在 47 64～ 1 1 1 1 6μg/ml、吡嗪酰胺在 1 37 76～ 32 1 44μg/ml范围内线性良好 ,r分别为 0 9999、 0 9991、 0 9999(n =9) ,平均回收率分别为 :99 57%、 99 51 %、 1 0 0 1 0 % ,RSD分别为 :0 71 %、 0 51 %、0 62 % (n =7)。结论 :本法简便、准确、灵敏度高     

血浆中美托洛尔的快速手性分离

本文建立了血浆中美托洛尔(Ⅰ)的直接手性分离方法。色谱条件采用Chiralcel OD分析柱(250×4.6 mm,id),RCSS硅胶预柱,流动相为异丙醇-正己烧-二乙胺(25:75:0.05,v/v),流速1.0 ml/min,荧光检测225 nm/295 nm。样品制备于每份0.5～1.0 ml血浆中加入100μl 1mol/L NaOH,涡旋10s,加正己烧3ml,振摇10min,离心(2000g,10min),水层于CO_2和甲醇混合液中冷冻,有机层于60℃挥去溶剂,残渣用50μl外标(S-烯丙洛尔)溶液(2μg/ml;溶剂为正己烷-异丙醇,5:1,v/v) 溶解,涡旋15s,进样     

HPLC法测定人血清中头孢呋肟浓度

本文建立了快速、简便测定人血清中头孢呋肟反相HPLC法,采用5×20mn不锈钢柱内填10um YWG-C_(18)H_(37)17定相,流动相甲醇:水:冰醋酸(28:71:1v/v),流速1.2ml/min,以头孢噻肟为内标物,紫外检测波长290nm,用10％三氯醋酸作蛋白沉淀剂,与血清之比为1:2(v/v)。头孢呋肟的日内回收率为100.34±6.60％,日间回收率为99.69±6.33％。头孢呋肟最低检测限为2ng,最低检测浓度为0.2μg/ml。在0.25～10μg/ml浓度范围内线性良好,相关系数r=0.9999。     

HPLC法定量测定血浆和组织中的头孢唑啉钠

用 HPLC 方法定量测定兔血浆和组织中的头孢唑啉钠,检出灵敏度分别为0.1μg/ml 和1μg/ml,线性范围为0.1～200μg/ml 和1～40μg/g,峰高比和头孢唑啉浓度的相关系数 r~2大于0.999。变异系数为2.54%和3.12%。方法操作简单,重复性好,灵敏度高,     

高效液相色谱法测定人血清美西律浓度

目的:用高效液相色谱法测定血清中盐酸美西律浓度。方法:以卡马西平为内标,采用C_(18)柱及保护柱;流动相为甲醇:磷酸缓冲液(55:45v/v),含乙腈0.5％(v/v);流速为0.6ml/min;提取液为正庚烷;采用紫外检测,检测波长为220nm。结果:美西律与内标分离良好,保留时间分别为9.64min和14.18min;在血清中提取的绝对回收率为84.61％;盐酸美西律在0.3～3.0μg/ml范围内线性关系良好,相关系数γ=0.9998,回归方程为Y=2.4337X-0.2595;日内及日间变异均<6％;最低检测浓度为 0.025μg/ml。结论:本方法适用于盐酸美西律的药物动力学研究。     

高产液相色谱法测定复方利福平片中利福平、异烟肝及吡嗪酰胺的含量

用HPLC法测定复方利福平片中利福平、异烟肼及吡嗪酰胺的含量.方法采用Spherisorb CN(250mm×4.6mm,5μm)色谱柱,流动相采用0.01mol/L庚烷磺酸钠溶液(pH2.2)-乙腈(4456,v/v),流速为2.0ml/min,检测波长为254nm.结果利福平在71.76～166.40μg/ml、异烟肼在47.64～111.16μg/ml、吡嗪酰胺在137.76～321.44μg/ml范围内线性良好,r分别为0.9999、0.9991、0.9999(n=9),平均回收率分别为99.57%、99.51%、100.10%,RSD分别为0.71%、0.51%、0.62%(n=7).结论本法简便、准确、灵敏度高.     

自动柱切换高效液相色谱法同时测定血浆中的SMZ和TMP

应用自制自动柱切换装置建立了同时测定SMZ及TMP血药浓度的HPLC方法.采用μBondapak C 18(50mm×4.6mm.37～50μm)为预处理柱,水为预处理流动相.分析柱为Hypersil BDS C18(150mm×4.6mm,5μm)柱,分析流动相为甲醇:磷酸缓冲液=35:65.检测波长230nm.SMZ和TMP分别在2.5～80μg/ml及0.125～4μg/ml范围内线性良好(r_1=0.999 7,r_2=0.9998).平均方法回收率分别为98.59%及95.71%;日内精密度分别为2.11%及2.67%,日间精密度分别为2.51%及2.89%;两者的最低血浆检测浓度可达SMZO.1μg/ml,TMPO.02μg/ml.方法迅速、简便、灵敏.     

布比卡因和利多卡因的临床血浓度监测

本文报告用高效液相色谱法同时测定血浆中布比卡因、利多卡因浓度。方法的线性范围分别为0.2～8μg/ml(布比卡因)和0.4～10μg/ml(利多卡因);r 值分别为0.9974和0.9900;检测限分别为0.06和0.03μg/ml;CV%一般均小于10%。并进行了方法的专一性试验。应用本法对布比卡因硬膜外阻滞后的血药浓度进行了监测,平均高峰浓度为1.73±0.70μg/ml,测得最高浓度为3.21μg/ml,未见不良反应发生。     

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.