鲁米诺-Ag(Ⅲ)化学发光新体系用于石杉碱甲的测定

目的:建立测定石杉碱甲的流动注射化学发光法。方法:在碱性介质中,石杉碱甲对鲁米诺-Ag(Ⅲ)化学发光体系有显著的增敏作用,建立了化学发光检测石杉碱甲的新方法。结果:在优化的条件下,石杉碱甲浓度在1.0×10-8～5.0×10-7mol·L-1范围内与化学发光强度呈线性关系;对浓度为2.0×10-7 mol·L-1的石杉碱甲溶液11次平行测定的RSD为2.6%;检出限为8.0×10-9 mol·L-1。结论:该方法简单、快速、灵敏,适用于药物制剂中石杉碱甲的含量测定。     

铈(Ⅳ)-亚硫酸钠体系化学发光分析法测定卡马西平

目的:建立一种测定片剂卡马西平含量的化学发光分析新方法。方法:在酸性条件下,卡马西平对铈(Ⅳ)和亚硫酸钠弱的化学发光有明显的增敏作用,并结合流动注射技术,建立了流动注射化学发光分析法测定卡马西平的新方法。结果:在优化的实验条件下,增敏的化学发光强度ΔI与卡马西平浓度在1.00×10-8～1.00×10-6g·mL-1的范围内呈良好的线性关系,检出限为6.0×10-9g·mL-1,RSD片剂含量测定;增敏为3.4%(3.0×10-7g·mL-1,n=11),并成功地应用于片剂中卡马西平含量的测定。结论:本方法操作简单且快速,适合于卡马西平的分析。     

基于纳米金催化鲁米诺-氯化汞化学发光新体系测定木犀草素

目的:基于纳米金对鲁米诺-氯化汞化学发光体系有良好的催化作用,建立测定木犀草素含量的高灵敏流动注射-化学发光分析法。方法:采用流动注射技术,实验研究了影响化学发光的各种因素;根据体系的化学发光光谱和紫外-可见吸收光谱结果,探讨了可能的化学发光机理。结果:0.1 mol·L-1氢氧化钠、4.0×10-4 mol·L-1鲁米诺、6.08×10-5 mol·L-1纳米金与1.0×10-3 mol·L-1 HgCl2组成最优的化学发光体系。在优化的实验条件下,本方法测定木犀草素的线性范围为2.0×10-9～1.0×10-7 g·mL-1(r=0.9929),检出限为1.5×10-9 g·mL-1,RSD为2.1%(C=1.0×10-8 g·mL-1,n=11)。纳米金作为电子转移的媒介,在鲁米诺-氯化汞反应过程中起催化作用;木犀草素和鲁米诺竞争与氯化汞发生反应,抑制了鲁米诺氧化成鲁米诺自由基,导致发光强度的降低。结论:利用本法成功地测定了血清与合成样品中木犀草素的含量。     

流动注射化学发光体系测定妥布霉素

本文利用妥布霉素对KMnO4-Na2SO3化学发光体系的发光有增敏的作用,结合流动注射技术,建立了流动注射化学发光法测定妥布霉素的新方法.在最佳条件下,妥布霉素溶液的浓度在5.0×10-7～1.0×10-5mol·L-1范围内与化学发光强度呈现良好的线性关系.该方法的检测限为1.0×100-7mol·L-1.对实际样品进行回收实验,结果令人满意,并对可能的发光机理进行了初步的探讨.     

鲁米诺-高锰酸钾化学发光法测定芦丁片中芦丁的含量

目的:建立一种快速、灵敏地测定芦丁含量的新方法。方法:利用在碱性条件下,芦丁对鲁米诺-高锰酸钾体系有强烈的增强作用的原理,结合流动注射技术,建立了流动注射化学发光法检测芦丁的新方法;反应试剂的浓度分别为:鲁米诺(2.0×10-5mol/L)、高锰酸钾(8.0×10-5mol/L)、氢氧化钠溶液(0.05mol/L),主泵(P1)、副泵(P2)流速分别为2.12、3.45ml/min,光电倍增管负高压为600V,采样时间为15s。结果:芦丁的检测质量浓度线性范围为2.0×10-9～2.0×10-7g/m(lr=0.9991),检出限为8.3×10-10g/ml,平均加样回收率为101.57%,RSD=1.69%(n=3)。结论:该方法简单、快速、灵敏性高,为芦丁药物的质量控制和体内分析提供了一种新的检测方法。     

流动注射化学发光法测定盐酸麻黄碱

目的:建立灵敏的流动注射化学发光分析测定盐酸麻黄碱的方法。方法:基于盐酸麻黄碱在酸性条件下对Ce(Ⅳ)-Na2 SO3化学发光反应的增敏作用,建立了流动注射化学发光测定盐酸麻黄碱的新方法。结果:在优化的条件下,测定盐酸麻黄碱的线性范围为8.0×10-8～2.0×10-6 g.mL-1(r=0.9941),检出限为2×10-8 g.mL-1。结论:该方法简便,且有较高的灵敏度和准确度,对麻黄碱药物分析以及毒品检测都有重要的意义。     

流动注射化学发光法测定姜黄素

目的:以Ce(Ⅳ)作为氧化剂,建立化学发光法测定中药成分姜黄素。方法:用Ce(Ⅳ)直接氧化姜黄素能产生弱发光,而罗丹明B(RhB)能大大增强此弱发光,由此建立了测定姜黄素的FIA-CL分析法。结果:测定姜黄素的线性范围为5.0×10-9~1.0×10-7mol.L-1,其检出限为3.0×10-9mol.L-1;对于1.0×10-8mol.L-1姜黄素进行11次测定的RSD为2.9%。结论:本方法简便、快捷且具有较高的灵敏度,可用于中药姜黄中姜黄素的分析。     

鲁米诺—高碘酸钾化学发光法测定盐酸阿朴吗啡

目的:在碱性条件下盐酸阿朴吗啡(Apomorphini Hydrochloridum)对luminol—KIO4化学发光体系具有很强的增敏作用,据此建立了流动注射化学发光法测定盐酸阿朴吗啡新方法。方法:线性范围为5.5×10-3～0.1 mg.L-1,检出限为4.4×10-3mg.L-1,RSD(n=10,c=0.02 mg.L-1)为2.6%,结果:已用于阿朴吗啡在尿样和血样中含量的测定,尿样中的加标回收率为97.32%～104.69%,血样中加标回收率为106.30%～110.57%。结论:由于其易见光分解,需使用合理的前处理手段。     

直接化学发光法测定土大黄苷及其机理研究

目的建立了一种快速、简便测定土大黄苷含量的流动注射化学发光新方法。方法在硫酸酸性介质条件下,高锰酸钾可直接氧化土大黄苷产生较强的化学发光,基于此建立了测定土大黄苷的新方法。结果在优化的条件下,测定土大黄苷的线性范围为1.0×10-8～1.0×10-6g·mL-1,检测限为0.2μg·L-1,对1.0×10-7g·mL-1的土大黄苷连续进行11次平行测定得到的相对标准偏差是1.4%。结论此方法灵敏度高,检测限低,快速准确。     

黄芩苷在多壁碳纳米管修饰玻碳电极上的电化学行为及其测定

目的建立了检测黄芩苷含量的电化学分析新方法。方法采用循环伏安法研究黄芩苷在多壁碳纳米管修饰玻碳电极上的电化学行为及其电极反应机理,以差示脉冲伏安法建立了检测黄芩苷含量的电化学分析新方法。结果在优化的条件下,电化学信号强度电流值I与黄芩苷浓度在1×10-9~5×10-7mol.L-1和6×10-7~5×10-6mol.L-1范围呈线性关系,相关系数为0.9956和0.9934。该方法的黄芩苷浓度检出限为1×10-10mol.L-1,平行测定6次得RSD为1.04%,回收率为98.0~102.0%。结论利用多壁碳纳米管修饰的玻碳电极分析法,建立了测定黄酮类药物黄芩苷的含量新方法,并应用于清开灵注射液中黄芩提取物（黄芩苷计）的含量测定,结果令人满意。     

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.     

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.