HPLC测定房水及血液中环孢霉素A浓度的实验研究

目的建立一种新的反相高效液相色谱法(RP-HPLC),用于测定房水及全血中的环孢霉素A(CsA)浓度。方法RP-HPLC测定房水及全血中的CsA浓度:ODS-C18柱(250mm×4.6mm,5μm);流动相为乙腈-水(70∶30);柱温60℃;检测波长210nm。结果采用乙腈-水-正己烷-甲醇的处理方法,CsA的峰面积与其浓度具有很好的线性关系:Y=339.2 X+4505.2,r=0.9991,CsA线性范围为62.6～626μg·L-1,最低检测浓度50μg·L-1,回收率98.7～103.6%,日内和日间变异系数小于4.0%,兔房水CsA浓度为144～466μg·L-1;大鼠全血CsA浓度在210～600μg·L-1。结论该样品与处理方法及HPLC检测方法简单、准确、经济,干扰少,可用于CsA的房水及血药浓度检测。     

改良RP-HPLC测定全血中环孢素A的浓度

目的建立一种简便的RP-HPLC法测定全血中环孢素A（CsA）的浓度,为临床合理应用CsA提供依据。方法全血样品1 mL经乙醚提取,正己烷洗涤去干扰后,采用Zorbax SB-C18柱（4.6 mm×150 mm,3.5μm）分离,流动相为乙腈-甲醇-水-异丙醇（60∶10∶29∶1）,流速1.5 mL.min^-1,柱温70℃,检测波长210 nm;环孢素D（CsD）为内标。结果CsA全血浓度在25-1 600 ng.mL^-1内线性关系良好（r=0.999 8）,平均方法回收率99.51%,日内、日间RSD均小于5%,最低检测限5 ng.mL^-1。结论本法简便快速,灵敏度高,重复性好,线性范围广。用于患者全血中CsA浓度监测,效果良好。     

改良RP-HPLC测定全血中环孢素A的浓度

目的 建立一种简便的RP-HPLC法测定全血中环孢素A(CsA)的浓度,为临床合理应用CsA提供依据。方法 全血样品1 mL经乙醚提取,正己烷洗涤去干扰后,采用Zorbax SB-C₁₈ 柱 (4.6 mm×150 mm,3.5 μm) 分离,流动相为乙腈-甲醇-水-异丙醇(60∶10∶29∶1),流速1.5 mL·min^-1,柱温70 ℃,检测波长210 nm;环孢素D(CsD)为内标。结果 CsA全血浓度在25~1 600 ng·mL^-1内线性关系良好(r=0.999 8),平均方法回收率99.51%,日内、日间RSD均小于5%,最低检测限5 ng·mL^-1。结论 本法简便快速,灵敏度高,重复性好,线性范围广。用于患者全血中CsA浓度监测,效果良好。     

HPLC法测定63名肾移植患者环孢素的全血浓度

目的建立测定全血中环孢素(CsA)浓度的HPLC方法。方法全血样品1 mL,乙醚提取,正己烷洗涤去干扰后采用Diamomil C_(18)柱(200 mm×4.6 mm,5μm)分离;流动相为乙腈-甲醇-水-异丙醇(58:24:17:1,V/V);流速1.0 mL·min~(=1);柱温65℃;检测波长210 nm;环孢素D为内标。结果CsA全血质量浓度为50～2 500μg·L~(-1)时线性关系良好(r=0.995 1)。方法回收率91.43%～96.48%,萃取回收率75.87%～84.96%,日内RSD<6.65%(n=5)。日间RSD<7.86%(n=5)。结论本方法较简便,准确可靠,可用于CsA药动学研究。     

高效液相色谱法测定肾移植受者环孢素A的血药谷值及两小时浓度

目的:建立全血中环孢素A(CsA)的RP-HPLC测定法,监测肾移植受者全血中CsA的C0、C2值.方法:RP-HPLC法色谱条件为:SB-C18柱,流动相为乙腈-甲醇-异丙醇-水(58:18:1:23),流速:1.4 mL·min-1,柱温70℃,检测波长208 nm.结果:CsA在51.25～1230μg·L-1范围内有良好的线性关系,r=0.999 3.绝对回收率为77.1%～90.2%,日内RSD≤10(n=6),日间RSD≤11.5(n=6).结论:此法简便、重现性好,可用于器官移植受者CsA的C0、C2的血药浓度监测.     

高效液相色谱法检测人全血环孢素A浓度

目的 建立RP-HPLC法测定全血中环孢素A(CsA)浓度的方法.方法 全血样品经乙醚单步萃取后,采用SB-C18色谱柱(4.6×150 mm,5 μm)进行分离,流动相为乙腈-甲醇-水-异丙醇(58:18:23:1),流速1.4 ml/min,柱温70℃,检测波长208 nm.结果 CsA在50～1 200 ng/ml范围内线形关系良好,最低检测浓度为15 ng/ml,方法平均回收率96.95%,日内RSD 4.31%～6.75%,日间RSD 5.58%～6.97%.结论 本方法稳定性好,灵敏度高,简便快速,可以满足临床器官移植患者CsA血药浓度监测的需要.     

HPLC法测定全血中环孢素浓度

目的建立测定全血中环孢素(CsA)浓度的固相萃取HPLC法。方法全血样品用硫酸锌甲醇混合液处理,取上清液进样C18(10 mm×3.9 mm)柱,经水冲洗去杂质后,用纯甲醇洗脱CsA,进入C18(250 mm×4.2 mm)柱,以流动相:乙腈-甲醇-水(60∶10∶30,V/V/V)洗脱后进行定量测定。结果本法最低检出浓度为40μg.L-1,线性范围为62.5~2 000μg.L-1,方法回收率为90%~95%,提取回收率>80%(n=5),日内RSD为3.25%~4.12%,日间RSD为3.37%~6.87%。结论本法测定CsA前处理步骤简便,结果可靠,可用于临床标本检测。     

反相高效液相色谱法测定全血中环孢素的浓度

目的:建立一种简便可行的RP-HPLC法测定全血中环孢素(CsA)的浓度,为临床合理应用CsA提供参考。方法:全血样品1ml经乙醚单步提取,正已烷洗涤去干扰后采用C_(18)柱(200mm×4.6mm,5μm)分离;流动相为乙腈-甲醇-水(72:6:22);流速为1.5ml·min~(-1);柱温为60℃;检测波长为210nm;环孢素D(CsD)为内标。结果:CsA全血浓度在50～1000ng·ml~(-1)范围内呈良好的线性关系(r=0.9996),平均方法回收率为96.6%～99.2%,平均萃取回收率为59.5%～65.3%;日内、日间RSD均小于6%,最低检测限为10ng·ml~(-1)。结论:本法简便、快速、准确可靠,用于移植术后患者及再生障碍性贫血患者的CsA血药浓度监测,效果良好。     

反相高效液相色谱法测定肾移植术后全血环孢素A浓度

目的建立单步萃取反相高效液相色谱法测定人全血中环孢素A(CsA)浓度。方法患者血样经乙醚单步萃取,环孢素D(CsD)为内标,C18色谱柱,乙腈-水(80:20)为流动相,流速1.0ml/min,柱温70℃,检测波长214nm。结果CsA全血浓度在50～600ng/ml范围内线性关系良好,r=0.9998,最低检测浓度为20ng/ml,平均回收率100.44%,日内和日间RSD均低于5%。结论反相高效液相色谱法简便灵敏、准确可靠、经济,可用于临床人体器官移植术后全血中CsA浓度的监测。     

RP-HPLC测定兔眼房水中环孢素浓度

目的:建立RP-HPLC测定兔眼房水中环孢素浓度,为环孢素局部缓释给药系统的药物动力学研究提供依据.方法:以环孢素D为内标物,兔眼房水标本0.2 ml经乙醚单步提取挥干后,20μl甲醇溶解回收,以C18硅胶键合相为固定相,乙腈:水(88:12)为流动相,紫外检测波长为200 nm,流速:0.1 ml·min-1;柱温:75℃.结果:CsA兔眼房水浓度在25～500ng·ml-1范围内呈良好的线性关系,r=0.996 5,方法的相对回收率为100.6%,绝对回收率为85.7%,日内和日间RSD均小于10%,最低检测限为10 ng·ml-1.结论:本方法灵敏度高,操作简单快速,结果可靠,可用于兔眼房水中CsA浓度检测.     

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.     

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.