抗体夹心酶联免疫吸附法测定重组E.coli L-门冬酰胺酶研究

用重组E.coliL-门冬酰胺酶免疫家兔，DEAE-纤维素柱层析纯化IgG，采用二步戊二醛交联法将辣根过氧化物酶标记抗体，建立抗体夹心酶联免疫吸附法，测定大鼠血浆中重组E.coliL-门冬酰胺酶浓度。本测定方法的线性范围为1～64U/L，灵敏度为0.4U/L。建立的抗体夹心酶联免疫吸附法测定大鼠血浆中重组E.coliL-门冬酰胺酶具有良好的精密度、回收率、灵敏度和特异性。     

双抗原夹心酶联免疫法检测抗白细胞介素-3的抗体

目的 :建立一种多用途、快速简便和易行的检测抗白细胞介素 3(IL 3)抗体的酶联免疫检测方法。方法 :以高纯度的基因工程人白细胞介素 3(rhIL 3)包被酶标板 ,以辣根过氧化物酶标记rhIL 3,建立了检测抗rhIL 3抗体的一步法双抗原夹心法。结果 :特异性 :与相似的蛋白分子 (其它细胞因子抗体 )无交叉反应 ,实验动物和人的正常血清反应呈阴性。灵敏度 :最低检出限为抗IL 3的单抗 5ng/ml。精密性 :组间和组内变异系数均 <1 2 %。应用于rhIL 3长期毒性实验取得良好的检测效果。结论 :此法特异性强、灵敏度高、方法稳定、操作简便 ,与其它细胞因子的单抗无交叉反应 ,能在同一条件下检测不同种属动物血清中的IL 3抗体 ,用于IL 3长期毒性实验等明显优于间接酶联免疫法。     

两种方法检测抗-HIV抗体的结果分析

用ELISA酶标二抗法及ELISA双抗原夹心法对健康献血者1500价标本进行抗—HIV检测,以及对8分阳性参比血清进行测定,发现双抗原夹心法与二抗的ELISA相比较有相近的灵敏度和更好的特异性。     

检测黑猩猩腺病毒68型抗原的双抗体夹心ELISA的建立

目的  建立定量黑猩猩腺病毒68型（chimpanzee adenovirus type 68，AdC68）含量的双抗体夹心ELISA，并验证其可行性。方法  用表达绿色荧光蛋白（green fluorescence protein，GFP）的非复制型AdC68（AdC68GFP）感染HEK293细胞，收获病变细胞并进行超速离心纯化AdC68GFP。用纯化AdC68GFP免疫家兔制备抗AdC68GFP抗体。以抗AdC68GFP抗体为包被抗体，辣根过氧化物酶标记的抗腺病毒HEXON IgG为酶标抗体，建立双抗体夹心ELISA，确定该法的线性范围，并验证该法的准确度、精密度、专属性和适用性。结果  纯化AdC68GFP的蛋白浓度为38.8 µg/ml，其中HEK293细胞的蛋白浓度低于0.3 µg/ml。双抗体夹心ELISA的最适包被抗体和酶标抗体浓度分别为1∶50和1∶500。该法的线性范围为0.06~3.88 µg/ml，线性相关系数为0.999 6。高、低浓度AdC68GFP样品的回收率分别为93.17%和94.33%，变异系数分别为6.72%和3.44%。该法可特异性检测AdC68GFP抗原，未发现与HEK293细胞蛋白发生交叉反应。应用该法检测AdC68GFP纯化过程中的样品可反映病毒的纯化效果。结论  建立的双抗体夹心ELISA具有良好的准确度、精密度和特异性，可用于AdC68纯化工艺过程中对病毒蛋白含量的快速检测。     

抗体夹心酶免疫吸附法测定重组E.coli水蛭素HV3研究

将重组E. coli水蛭素HV3和BSA交联后免疫豚鼠和家兔,DEAE-纤维素柱层析纯化IgG.用这两种抗体和酶标二抗羊抗兔IgG-HRP建立三抗体夹心酶联免疫吸附法,测定重组E. coli水蛭素HV3的含量.本测定方法的线性范围为0～2 ng/ml,灵敏度为0.04 ng/ml.建立的三抗体夹心酶联免疫吸附法测定重组E.coli水蛭素HV3具有良好的精密度、回收率、灵敏度和特异性.     

磁分离酶联免疫检测激素的方法学评价

目前在国内检测人血清内的激素可采用放射免疫(RIA)、酶免疫(EIA)和时间分辨荧光免疫等方法[1] 。瑞士雪兰诺诊断中心发明的磁分离酶联免疫是一种非同位素标记的酶免疫检测技术,称为磁性抗体免疫技术(MAIA)。我们用磁分离酶联免疫方法测定了30份人血清标本中的六种内分泌激素(FSH、LH、PRL、P、E2 、T) ,通过其线性特征、显色稳定性、精密度、特异性等实验结果,并与放射免疫法测定结果作比较,对该方法作出初步的评价。1　实验原理MAIA双抗夹心法测FSH、LH、PRL是以待测物作为抗原,同时与碱性磷酸酶(ALP)标记抗体和异硫氰酸荧…     

应用酶联免疫吸附实验检测肠出血性大肠杆菌O157:H7

目的:制备和纯化O157:H7抗原,免疫家兔和豚鼠,获得高效价的抗O157:H7免疫血清并进行纯化及酶标记.建立对O157:H7感染患者快速诊断方法,做到早期发现及时治疗,有效控制疫情的蔓延. 方法ELISA双抗体夹心法检测O157:H7抗原.步骤:包被特异性抗体,加处理后的粪便等标本,然后加入抗O157:H7酶结合物,最后加入底物显色.结果本课题所研制的抗O157:H7酶结合物只对O157:H7呈阳性反应,而与其他相关细菌无交叉反应.结论应用酶联免疫吸附试验(即双抗体夹心法)对肠出血大肠杆菌O157:H7抗原的检测较常规法实验程序简捷、快速、敏感.临床和现场验证结果表明,其方法具有灵敏度高,特异性强操作简单等特点,为肠出血性大肠杆菌O157:H7的鉴定及快速诊断提供了一种新的检测手段.     

促红细胞生成素酶联免疫吸附测定法的研究

目的:建立血清促红细胞生成素(erythropoietin, EPO)的酶联免疫检测(ELISA)方法,观察其临床应用价值.方法:制备EPO多克隆抗体,异丙醇洗涤处理酶标板以增强其吸附能力,利用交叉反应法选择出抗原、抗体及酶标抗体的最佳的配对工作浓度.反应后,观察本方法的灵敏度、回收率、特异度、稳定性等指标,观察效果.以正常血清为对照组,测定缺铁性贫血组、乳腺癌组,并与放射免疫检测对比.结果:酶标板结合蛋白能力增强.抗体、酶标抗体、抗原最佳工作浓度分别为1∶1 000,1∶6 000,1∶800.灵敏度为0.46 U/L,与生长激素、铁蛋白交叉反应率低;高浓度、低浓度样品平均回收率分别为96.3%、97.3%,批内和批间变异分别为8.31%、7.82%,稳定性好.乳腺癌组、缺铁性贫血组EPO水平均明显高于正常对照组.放射免疫检测及酶联免疫检测检出结果差别无统计学意义.结论:本血清EPO双抗体夹心ELISA法的建立在诊断相关疾病方面有一定的临床应用价值.     

鼠源神经生长因子临床受试者血清抗体检测

目的：采用酶联免疫测定法（ELISA）检测鼠神经生长因子临床用药病人的血清抗体。方法：通过直接标记鼠神经生长因子（NGF），建立了一种检测人抗鼠NGF抗体的检测方法：即双抗原夹心法检测人抗鼠NGF抗体。将此方法应用于检测临床用药病人的血清抗体，并与间接法进行了比较。结果：双抗原夹心源检测94份正常人血清，无一份假阳性，在检测临床病人血清时，亦得到了较好的结果。而间接法的非特异性则达10％。结论：双抗原夹心法方法可靠，可用于鼠源神经生长因子临床试验；血清样本检测证明临床实验病人血清抗鼠NGF抗体含量与正常人无显著差异。     

基于IgY的ELISA用于囊尾蚴循环抗原的检测

目的 建立基于IgY的双抗体夹心ELISA用于囊尾蚴病的诊断.方法 制备并纯化抗囊尾蚴循环抗原(CA)卵黄抗体(IgY),建立以抗CA的IgY为捕获抗体,酶标记抗CA的单克隆抗体1A5为检测抗体的双抗体夹心ELISA法,共检测样品450份,并与捕获抗体和检测抗体均为单克隆抗体的ELISA法比较,验证方法的敏感性、特异性与实用性.结果 成功制备并鉴定了特异性IgY抗体,建立了基于Igy的双抗体夹心ELISA检测体系.IgY-ELISA和双单抗-ELISA检测囊尾蚴CA的灵敏度分别为8.3 μg/L和13.9 μg/L.IgY-ELISA检测囊尾蚴病患者血清与脑脊液的CA阳性率分别为100％ (139/139)与89.5％ (17/19),囊尾蚴病猪血清的阳性率100％ (222/222),健康人与健康猪血清的阴性率为100％.结论 建立的基于lgY的双抗体夹心ELISA检测囊尾蚴CA用于囊尾蚴病诊断,具有较高的特异性和敏感性,可用于囊尾蚴病的辅助诊断.     

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.     

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.     

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.