空心莲子草有效部分的分离及抗病毒作用

采用铅盐沉淀法和两相溶剂萃取法提取空心莲子草的若干部分,进行抗病毒研究,结果表明石油醚,乙醚和醋酸乙酯提取物有抗EHFV作用。抗病毒有效成分为香豆精类化合物。     

Chloroactivated latex particles for covalent coupling of antibodies. Application to immunoassays

The aim of the present work is to prepare and characterize a functionalized latex with chloromethyl groups on the surface and to perform the covalent coupling of anti-human serum albumin (a-HSA) IgG protein. The chloromethyl-styrene latex (CMS) was synthesized by means of a core-shell emulsion polymerization in a batch reactor. The monodisperse-obtained latex was characterized by determining the diameter (TEM and PCS), the surface charge density (conductometric and potentiometric titration), the amount of chloromethyl groups on the surface (hydrolysis reaction), and the stability vs electrolyte concentration (turbidity measurements). Electrokinetic characterization was also performed (electrophoretic mobility versus pH and ionic strength). IgG was chemically bound to the latex particles under different sensitization and block-stabilization conditions. Colloidal stability of complexes was studied to select an immunolatex suitable for the development of latex immunoassays. The final part of this work consists of a study of the immunoreactivity of the IgG-latex complexes at different pH and ionic strength, in particular under physiological conditions. The results show that chemically bound IgG to chloromethyl latex provides an IgG-latex complex suitable for application in immunodiagnosis tests.     

A simple and rapid assay to evaluate purity of foot-and-mouth disease vaccine before animal experimentation

Currently, foot-and-mouth disease (FMD) vaccine purity is tested in cattle to detect antibodies against the non-structural protein (NSP) after repeated immunization with the final vaccine product. In case of vaccine failure, the manufacturing company would suffer significant economic loss. To prevent such unfortunate losses with the final vaccine product, in vitro testing is required to quantitate an NSP antigen during the manufacturing process prior to animal experiments. A novel lateral-flow assay device was developed using a monoclonal antibody (MAb) against the 3B NSP. To determine the minimal amount of NSP required to elicit antibodies in livestock, goats were immunized several times with various concentrations of either the recombinant 3AB (rec.3AB) protein or FMD virus culture supernatant. Antibodies against 3AB were elicited after a second immunization with 10.6 ng to 42.5 ng of rec.3AB and a third immunization with a 10-fold diluted FMD virus culture supernatant in goats. The lateral-flow assay device detected the minimal amount of rec.3AB and native NSP in FMD virus culture supernatant required to induce NSP antibodies in goats. The in vitro assay device is simple and economical, provides rapid results, and should be useful for FMD vaccine-manufacturing companies prior to conducting animal experiments to test the vaccine purity.     

Detection of anti-cytokine antibodies and their clinical relevance

Cytokines regulate many aspects of cell growth and differentiation and play pivotal roles in the orchestration of immune defence against invading pathogens. Though ‘self’ proteins, they are potentially immunogenic and can give rise to anti-cytokine autoantibodies (aCA). The main foci of the article are a critical summary of the various methodologies applied for detecting and measuring aCA and a broad review of studies of the occurrence, characterization and clinical relevance of aCA in normal healthy individuals, patients with autoimmune diseases or microbial infections and aCA in patients whose disease is treated with recombinant cytokine products. The need for technical and methodological improvement of assays, including validation and standardization, together with approaches to harmonize calculation and reporting of results is also discussed.     

Laboratory diagnosis of heparin‐induced thrombocytopenia

Heparin‐induced thrombocytopenia (HIT) is a clinical‐pathological disorder; thus, laboratory testing for the pathogenic platelet‐activating antiplatelet factor 4 (PF4)/heparin antibodies is central for diagnosis. The “iceberg” model summarizes the inter‐relationship between platelet activation assays and PF4‐dependent immunoassays, with platelet‐activating antibodies comprising a subset of anti‐PF4/heparin antibodies. The platelet serotonin‐release assay (SRA), performed by reference laboratories, has high sensitivity and specificity for HIT (~95% each), and is especially suited for detecting highly pathogenic HIT sera containing both heparin‐dependent and heparin‐independent platelet‐activating antibodies; this latter subgroup of antibodies explains “autoimmune HIT” disorders (delayed‐onset, persisting, spontaneous, heparin “flush,” fondaparinux‐associated). Recently, SRA‐negative HIT has become recognized, in which serum from some HIT patients contains subthreshold levels of platelet‐activating antibodies (by SRA) that become detectable using a PF4‐enhanced platelet activation assay. Unusual immunologic features of HIT include early antibody detectability (at onset of platelet count fall) and antibody transience (seroreversion). Widely available PF4‐dependent enzyme immunoassays (EIAs) have high sensitivity but poor specificity for HIT, although specificity is enhanced with IgG‐specific EIAs and strong positive results; unfortunately, EIA results are usually not available in real time. Automated rapid immunoassays, such as the chemiluminescence immunoassay (CLIA) and latex immunoturbidimetric assay (LIA), facilitate real‐time laboratory diagnosis. Recently available likelihood ratio (LR) data for positive (LR+) and negative (LR?) test results allow clinicians to adjust their pretest probabilities for HIT, using Bayesian analysis, into real‐time posttest probabilities that are dramatically increased (test positive) or decreased (test negative). Moreover, (semi‐)quantitative CLIA‐ and LIA‐positive results (weak, moderate, strong positive) can further refine the posttest probability of HIT.     

Reference values of thirty-one frequently used laboratory markers for 75-year-old males and females

Background

We have previously reported reference values for common clinical chemistry tests in healthy 70-year-old males and females. We have now repeated this study 5 years later to establish reference values also at the age of 75. It is important to have adequate reference values for elderly patients as biological markers may change over time, and adequate reference values are essential for correct clinical decisions.

Methods

We have investigated 31 frequently used laboratory markers in 75-year-old males (n = 354) and females (n = 373) without diabetes. The 2.5 and 97.5 percentiles for these markers were calculated according to the recommendations of the International Federation of Clinical Chemistry.

Results

Reference values are reported for 75-year-old males and females for 31 frequently used laboratory markers.

Conclusion

There were minor differences between reference intervals calculated with and without individuals with cardiovascular diseases. Several of the reference intervals differed from Scandinavian reference intervals based on younger individuals (Nordic Reference Interval Project).     

MODIFIED RESPONSES TO PGE2 IN POLYAMINE BIOSYNTHESIS BY T LYMPHOCYTES OF GASTRIC- AND CONJUNCTIVA BASAL CELL-CARCINOMA PATIENTS

The response to Prostaglandin (PG) E₂ of T cells from gastric carcinoma (GC)- and conjunctiva-basal cell carcinoma (conjunctiva-BCC)-bearing patients has been studied in relation to polyamine metabolism. Polyamines are crucial cofactors in cell growth as well as differentiation and many works report that lymphocyte spermine (SP), spermidine (SPD) and putrescine (PUT) levels may be related to tumor proliferation. The present work aims to detect the basal and PGE₂ induced concentrations of these polyamines and cAMP, ornithine decarboxylase (ODC), spermine N1-acetyltransferase (SAT) activities of T lymphocytes drawn from patients suffering from GC and conjunctiva-BCC since many carcinomas are characterized by high levels of PGE₂. Data obtained from lymphocytes of neoplastic subjects were compared with those derived from PGE₂-treated control lymphocytes. Results highlight a very significant increase of all the polyamine metabolites in PGE₂-treated T cells from neoplastic patients in respect to the untreated and PGE₂-treated control lymphocytes. Therefore, it is conceivable that the PGE₂ content increase, often occurring during the epithelial tumour development, may contribute, through enhancement of polyamine metabolism, to tumor progression.     

Assessment of soy aeroallergen levels in different work environments

Background Airborne soybean hull proteins are known causes of asthma epidemics around harbours and soy processing plants. Soy flour dust proteins may cause occupational allergy in food and feed industries. Objective To compare enzyme immunoassays (EIAs) for soy hull and soy flour aeroallergens, exposure assessment in various work environments. Methods Airborne dust samples (n=324) from soy unloading and/or processing plants, the animal feed industry and pig stables were analysed by two soy flour assays: one assay for measuring complete soy hull proteins and two assays for measuring the purified low‐molecular‐weight (LMW) soy hull allergens. Results Immunoblotting confirmed strong differences between antibody specificities and soy preparations. The results of the two soy flour assays and the assay for measuring complete soy hull proteins were highly correlated (r>0.85). The two LMW soy hull assays also showed a strong mutual correlation (r=0.91), but much less correlation with assays for measuring soy flour and complete soy hull. The levels of LMW soy hull proteins were the highest at sites of soybean unloading or processing, while soy flour levels were particularly high in the soy and animal feed industry. Conclusions The optimal EIA procedure for soy aeroallergen exposure assessment depends on the type of work environment and the local soy dust composition. Thus, the type of work environment should always be taken into account in future soy allergy studies in order to prevent a possible underestimation of the workers' actual risk of developing soy allergy.     

房水病毒载量和细胞因子检测在急性视网膜坏死诊断与治疗中应用的临床研究

目的探讨房水病毒载量和细胞因子检测在急性视网膜坏死(ARN)诊断治疗中的作用。 方法回顾性分析2017年3月至2021年7月于北京地坛医院眼科就诊ARN患者10例(13只眼)的病例资料。其中，男性8例(10只眼)，女性2例(3只眼)；年龄24~66岁，平均年龄(35.1±10.2)岁。采集所有患者的房水，明确病毒种类。将患者治疗前房水中病毒载量高于10⁵拷贝/ml定义为高载量组，低于者定义为低载量组。对所有患者均行静脉和玻璃体腔注射更昔洛韦治疗；对视网膜脱离者行玻璃体切除视网膜复位术或视网膜激光光凝术。检查所有患者治疗前后的最佳矫正视力、眼前节及眼底情况。采用聚合酶链式反应检测所有患者治疗前和每次随访时房水的病毒载量；采用流式细胞微球捕获芯片技术检测患者治疗前和随访时房水白细胞介素(IL)-6及IL-8的含量。房水病毒载量的下降速度以log(病毒载量)拷贝/ml表示。最佳矫正视力以例数和百分比表示；注射次数、房水病毒载量、IL-6及IL-8以中位数和四分位数表示。 结果ARN患者10例(13只眼)均为感染水痘带状疱疹病毒(VZV)导致，治疗后视网膜病变均得到有效控制，玻璃体腔注射次数为2~9次，平均中位数和四分位数6(5，9)次。继发视网膜脱离者4例(5只眼)，占38.46%(5/13)。其中，行玻璃体切除术者3例(3只眼)，占60.00%(3/5)；行视网膜激光光凝术1例(2只眼)，占40.00%(2/5)。患者治疗前房水VZV平均载量的中位数和四分位数为2.69×10⁵(4.27×10⁴，9.26×10⁷)拷贝/ml；治疗2周后病毒载量开始下降，logVZV平均每周下降(0.67±0.30)拷贝/ml；治疗6周后升高者3例(5只眼)，占38.46%(5/13)。患者治疗前房水IL-6和IL-8平均含量的中位数和四分位数分别为2993.3(1655.9，18751.3)pg/ml和253.6(195.8，1682.2)pg/ml；治疗2周后分别为398.1(251.2，2511.8)pg/ml和63.1(15.8，125.9)pg/ml，较治疗前明显下降。高载量组和低载量组患者的病程分别为(14.00±4.47)d和(11.33±8.26)d，前者时间长于后者19.07%。高载量组和低载量组患者平均注射次数的中位数和四分位数分别为7(6，9)和6.5(4，9)。高载量组和低载量组患者终末最佳矫正视力≥0.1者分别为2例(2只眼)和4例(4只眼)，分别占15.38%(2/13)和30.77%(4/13)；<0.1者分别为4例(5只眼)和2例(2只眼)，分别占38.46%(5/13)和15.38%(2/13)。高载量组和低载量组继发视网膜脱离者分别为4例(4只眼)和1例(1只眼)，分别占30.77%(4/13)和7.69%(1/13)。 结论ARN患眼房水的病毒载量在治疗后，经历平台期和对数下降期，并最终低至可检测阈值以下。房水IL-6和及IL-8含量可以评估眼内炎的严重程度。房水检测可以明确病毒种类，监测炎症反应和治疗效果，对于ARN的诊断与治疗具有重要参考价值。