Evaluation of an enzyme immunoassay for detection of Neisseria gonorrhoeae in an adolescent population

We compared a modified procedure of Gonozyme , an enzyme immunoassay for detection of gonococcal antigen in urogenital specimens, with bacterial culture for Neisseria gonorrhoeae in a hospital-based adolescent clinic. In 839 patients studied, prevalence of urogenital gonorrhea by culture was 14.3%. The sensitivity of the immunoassay was 90.0%, and the specificity was 98.1%; predictive values for a positive and a negative test result were 88.5% and 98.3%, respectively. Gonozyme was highly accurate in 57 males studied; sensitivity, specificity, and predictive values were 100%. In 782 females, sensitivity was 87.5%, specificity was 98.0%, positive predictive value was 85.7%, and negative predictive value was 98.2%. Patients with false-negative immunoassay results had lower colony counts on culture. Gonozyme is an acceptable substitute for culture in males and in females with intermediate or high prevalence of gonorrhea. Results can be available within three hours.     

Absence of antibodies to HTLV-III in health workers after hepatitis B vaccination

A proportion of the plasma for the triply inactivated, plasma-derived hepatitis B vaccine produced in the United States is obtained from homosexual men. Because homosexual men are a high-risk group for the acquired immunodeficiency syndrome (AIDS), concern has emerged that the vaccine could harbor the AIDS agent. To evaluate this risk, we tested 15-month postvaccination serum samples for antibodies to human T-cell lymphotropic virus type III in 100 health care workers who had received inactivated hepatitis B vaccine lots made from plasma collected between 1977 and 1979 and 100 who had received placebo injections. None of the 200 health workers had serological evidence of human T-cell lymphotropic virus type III infection. These serological findings lend additional support to earlier epidemiologic and immunologic observations suggesting that hepatitis B vaccine does not transmit infection with an AIDS virus.     

Intrathecal synthesis of antibodies to HTLV-III in patients without AIDS or AIDS related complex

De novo synthesis in the central nervous system of IgG antibodies to human T cell lymphotropic virus type III (HTLV-III) (lymphadenopathy associated virus) was shown in seven of 10 seropositive men who had syphilis but not the acquired immune deficiency syndrome (AIDS) or AIDS related complex. None of these men showed neurological symptoms when the serum and cerebrospinal fluid were collected. Pleocytosis was present in all 10. Of the seven men who showed evidence of intrathecal synthesis of antibodies, five had increased total concentrations of IgG and four had oligoclonal IgG bands in their cerebrospinal fluid. Oligoclonal bands were also present in one man who did not have any antibodies. Longitudinal study of one man showed that seroconversion preceded intrathecal synthesis of antibody specific to HTLV-III. The appearance of antibody in the cerebrospinal fluid was accompanied by a transient rise in mononuclear cell count and the appearance of oligoclonal bands. The presence of clones of B cells specific to HTLV-III in the central nervous system of these patients without persisting neurological symptoms suggests that HTLV-III enters the central nervous system in the early stages of infection.     

Seroepidemiology of HTLV-III antibodies in a remote population of eastern Zaire

A human retrovirus--human T cell lymphotropic virus-III (HTLV-III)--has recently emerged as the probable cause of acquired immunodeficiency syndrome (AIDS). In May 1984, 250 outpatients at a hospital in a remote area of eastern Zaire were surveyed for AIDS type illnesses and the prevalence of antibodies against HTLV-III determined by an enzyme linked immunosorbent assay using disrupted whole HTLV-III virus as the antigen. No clinical cases of AIDS were diagnosed among these patients. Overall, 31 (12.4%) had clearly positive ratios (greater than or equal to 5.0) and a further 30 (12.0%) had borderline ratios (3.0- less than 5.0). Western blots of serum samples from subjects with antibodies yielded bands consistent with HTLV-III as found in American patients with AIDS and members of groups at risk of AIDS. The prevalence of antibody was highest in childhood (p = 0.02); among adults prevalence rose slightly with age. HTLV-III antibodies were more common among the uneducated (p = 0.006), agricultural workers (p = 0.03), and rural residents (p = 0.006), but the Western blot bands were generally weak in this group. By contrast, one urban resident had strong bands. The relatively high prevalence of antibodies among the rural poor in this area of Zaire suggests that HTLV-III or a closely related, cross reactive virus may be endemic in the region. A different natural history of infection, perhaps in childhood, may also explain the findings.     

Usefulness of enzyme immunoassay (EIA) for screening of anti HIV antibodies in urinary specimens: A comparative analysis

Background

Standard HIV testing is done using serum or plasma. FDA approved ELISA to screen urine for IgG antibodies to HIV-1 in 1996. It is a simple, noninvasive test and is appropriate for developing countries where health care personnel may not be professionally trained or where clean needles for drawing blood may not always be available.

Methods

436 individuals with high-risk behavior and strong clinical suspicion of HIV infection were screened for IgG antibodies to HIV-1 in urine by ELISA. Urine HIV testing was performed by enzyme immunoassay, at the ongoing Voluntary Confidential Counseling and Testing Center (VCCTC) at a large tertiary care microbiology lab. The individuals enrolled for the study had high-risk exposure to the virus and majorities were from a state with a high incidence of HIV infection. In all individuals, both serum and urine were tested for IgG antibodies to HIV-1.

Results

Overall, 135 individuals (30.96%) were HIV-positive, of whom 96 (71%) had never previously tested positive; 87% of those who tested positive received their results, and most were referred for medical care. Sensitivity, specificity and predictive values of HIV-1 urine ELISA test kit were determined. Sensitivity was found to be 89.6%; 95% CI [82.9–94.0], specificity 97.3%; 95% CI [94.6–98.8], positive predictive value 93.8%; 95% CI [87.8–97.1] and negative predictive value 95.4%; 95% CI [92.3–97.4].

Conclusion

Efficiency, sensitivity, and specificity of the urine-based screening for HIV-1 test kits were excellent as compared to the reference test.     

Usefulness of enzyme immunoassay (EIA) for screening of anti HIV antibodies in urinary specimens: A comparative analysis

Background

Standard HIV testing is done using serum or plasma. FDA approved ELISA to screen urine for IgG antibodies to HIV-1 in 1996. It is a simple, noninvasive test and is appropriate for developing countries where health care personnel may not be professionally trained or where clean needles for drawing blood may not always be available.

Methods

436 individuals with high-risk behavior and strong clinical suspicion of HIV infection were screened for IgG antibodies to HIV-1 in urine by ELISA. Urine HIV testing was performed by enzyme immunoassay, at the ongoing Voluntary Confidential Counseling and Testing Center (VCCTC) at a large tertiary care microbiology lab. The individuals enrolled for the study had high-risk exposure to the virus and majorities were from a state with a high incidence of HIV infection. In all individuals, both serum and urine were tested for IgG antibodies to HIV-1.

Results

Overall, 135 individuals (30.96%) were HIV-positive, of whom 96 (71%) had never previously tested positive; 87% of those who tested positive received their results, and most were referred for medical care. Sensitivity, specificity and predictive values of HIV-1 urine ELISA test kit were determined. Sensitivity was found to be 89.6%; 95% CI [82.9–94.0], specificity 97.3%; 95% CI [94.6–98.8], positive predictive value 93.8%; 95% CI [87.8–97.1] and negative predictive value 95.4%; 95% CI [92.3–97.4].

Conclusion

Efficiency, sensitivity, and specificity of the urine-based screening for HIV-1 test kits were excellent as compared to the reference test.     

改良亲和酶标法检测乳腺癌细胞ER

0　引言　乳腺癌术后选择何种治疗方法,主要依据乳腺癌组织中雌激素受体(ER)的检测决定的.ER阳性者选择内分泌治疗,其有效率为50%～75%;ER阴性者,治疗有效率只有8%～10%,一般采取其他治疗方法.为了提高检测ER亲和酶标法的灵敏度和准确度,我们以经典DCC法作参照,对亲和酶标法进行改良,获得了较好的结果.1　材料和方法1.1　材料　本院普外科经临床及病理确诊、手术切除的乳腺癌患者标本18例,立即取癌组织约1g送生化室作ER的生化测定(DCC法)[1],同时取癌组织(≥0.5mm×0.5mm×0.3mm)1～2块作石蜡包理.连续切片,片厚5μm.1.2　方法1.2.1…     

单克隆抗体酶联免疫吸附测定甲胎蛋白方法的建立

应用二种抗甲胎蛋白(AFP)不同抗原决定簇的单克隆抗体分别与纤维素及酶结合,建立酶联免疫吸附测定(ELISA)法。应用这种方法测定18例人血清标本,结果与放射酶免疫测定比较,二者趋于一致。此外,本文对单克隆抗体的ELISA与抗血清的RIA进行了比较与讨论。     

Screening test for HTLV-III (AIDS agent) antibodies. Specificity, sensitivity, and applications

The third member of the human T-cell leukemia (lymphotropic) retrovirus family (HTLV-III) is a newly discovered retrovirus that has been closely associated with the acquired immunodeficiency syndrome (AIDS). In our application of an enzyme-linked immunosorbent assay (ELISA) for HTLV-III antibodies, 72 (82%) of 88 patients with AIDS were positive, 14 (16%) were borderline, and two (2%) were negative. In contrast, only 1% of 297 volunteer blood donors were positive, 6% were borderline, and 93% were negative, demonstrating that this ELISA for HTLV-III antibodies is highly specific and sensitive for AIDS (excluding borderline results, 98.6% and 97.3%, respectively). Among persons at high risk for AIDS, 8% had borderline results, with positive and negative results readily distinguished as bimodal distributions that paralleled the temporal and geographic trends in AIDS. None of the 188 laboratory and health care employees working with patients with AIDS or their specimens were positive for HTLV-III antibodies, indicating that current precautions for health care workers appear adequate. This ELISA for HTLV-III antibodies will be a useful screening test among blood donors and populations at risk for AIDS, will aid in the diagnosis of suspected AIDS, and will help in defining the spectrum of diseases that are etiologically related to HTLV-III.     

生物素-链霉亲和素技术一步法检测人心肌肌钙蛋白T

目的：用已获得的两株抗人心肌肌钙蛋白T(cTnT)单克隆抗体N15C和N16D建立检测cTnT的生物素—链霉亲和素技术一步法。方法：应用酯化生物素对N15C进行标记,应用辣根过氧化物酶对N16D进行标记。将待检血清或抗原标准品、生物素标记的N15C和酶标记N16D加入经链霉亲和素包被的96孔酶标板微孔中,然后加入OPD,硫酸终止反应后,在λ=490nm处读取A值,根据标准曲线求出各样本值。结果：建立的方法检测cTnT,检测灵敏度为1．0μg／L,可定量检测范围为2．0～32．0μg／L。11例AMI患者和10例正常人用该法进行血清检测,与Enzymun—Test TnT试剂盒相比,阳性符合率为82％,特异性为100％。经重复检测表明本方法检测低浓度cTnT批内变异系数为4．70％,批间变异系数为9．36％;检测高浓度cTnT批内变异系数为3．20％,批间变异系数为8．25％。结论：该方法特异性高,重复性好,较常规双抗体夹心ELISA法有更高的灵敏度。     

国产化学发光免疫分析系统检测AFP的性能评价

目的:探讨不同化学发光检测系统测定甲胎蛋白(AFP)结果的可比性,探讨不同检测系统的临床适用性。方法:依据美国临床实验室标准化协会(CLSI)EP9-A2文件的规定,以罗氏cobas-e601电化学发光免疫分析仪检测结果为参比系统(X),以迈瑞CL-2000i全自动化学发光免疫分析仪测试结果为待对比系统(Y),通过检测AFP指标,对两套系统结果进行对比分析和偏倚评估。结果:两检测系统对AFP的检测结果具有良好的相关性,相关系数大于0.95;预期偏差均在可接受范围内,具有良好的一致性。结论:国产迈瑞CL-2000i全自动化学发光免疫分析仪检测AFP能够满足临床需要,可以推广应用。     

酶免疫测定法对外周血单个核细胞内IL-4的检测

目的 :评价酶免疫测定法检测人产生IL 4的单个核细胞的有效性。方法 :使用酶免疫测定法和流式细胞术测定类风湿性关节炎患者 (RA组 )和正常人 (对照组 )外周血单个核细胞中产生IL 4的细胞数。结果 :用两种方法测各组所得结果均高度相关 (患者组r=0 .95 7,对照组r =0 .96 9) ;与对照组相比 ,RA患者产生IL 4的细胞数明显升高 (t=2 .478,P <0 0 5 )。结论 :酶免疫测定法可代替流式细胞术测定胞内细胞因子 ,并可用于临床Th1和Th2分群。     

Monoclonal antibodies in ABO serology: an evaluation

Monoclonal anti-A and anti-B reagents produced from mouse 'hybridoma' cells have been evaluated by comparative and standard serological techniques and found suitable for use as potent routine blood grouping reagents. They have an avidity time of only 9-12 seconds and their reactions are pH dependent with optimal reactions around neutral pH. The antisera gave good agglutination reactions at room temperature. The cost effectiveness and advantages of monoclonal antibodies include their high potency and the possibility of their production in unlimited amounts from in-vitro cultures.     

A "dipstick" enzyme immunoassay for detection of antibody to Brucella abortus in cattle sera

An enzyme immunoassay that utilizes antigen bound to a matrix which can be removed from the substrate to stop development is described. The assay which is performed in glass or plastic disposable tubes uses Gel-Bond film strips for attachment of antigen. The only equipment requirements are a rotary shaker and a spectrophotometer (optional). The antigen coated strips are passed through a series of tubes containing test serum, wash solution, antibody-enzyme conjugate, wash solution and substrate-chromogen taking about 45 minutes to perform. In testing sera with or without antibody to Brucella abortus a very high correlation existed between same day tests and tests performed over several days as well as with data on the same sera obtained by an enzyme immunoassay in a microtiter format.     

Determination of Progesterone Receptor by Chemiluminescent Enzyme Immunoassay

Itis well known thatthe origin and the progressof the hormone- dependenttumors have close relationto the status of hormone receptors,especially inbreast cancer and endometrial cancer.The level ofprogesteronereceptor(PR) can notonly show the ef-fect of hormone therapy,but indicate the prognosisof patients as well.The assays for determination ofhormone receptor commonly used now in clinicalpractice have some disadvantages.Chemiluminescentenzyme immunoassay(CLEIA) used in this study isderived …     

改良哥伦比亚巧克力培养基分离流感嗜血杆菌

目的：评价自制的改衣哥伦比亚巧克力琼脂培养对流感嗜血杆菌的分离效果。方法：将Ｈ接种于ＩＣＣＡ和其他４种Ｈｉ培养基上,计算和比较５种培养基中Ｈｉ的平均生长指数;用ＩＣＣＡ对８７８份呼吸道标本进行培养后检测Ｈｉ。结果;ＩＣＣＡ培养的Ｈｉ平均生长指数为１７．７９     

化学发光微粒子免疫法检测人附睾蛋白方法学性能评价

目的 对Abbott Architect i2000SR检测系统应用化学发光微粒子免疫技术定量测定人附睾蛋白（HE4）的分析性能进行评价。方法 参考美国临床实验室标准化协会（NCCLS）文件,制定定量检测方法的方法学评价方案,通过Abbott Architect i2000SR检测系统测定HE4的批内精密度、批间精密度、线性范围、携带污染率和参考区间。结果 低、高值混合血清批内精密度CV分别为1.80%、 2.34%;批间精密度CV分别为2.03%、 2.70%;线性范围为19.8~1573.5 pmol/L;携带污染率为-0.02%;参考区间为0.0~140.0pmol/L。结论 Abbott Architect i2000SR检测系统测定HE4的精密度好、线性范围宽、携带污染率低,参考区间与厂家提供的一致,检测性能可满足临床要求。