Detection results of blood donors with HBsAg reactivity to single reagent: a retrospective analysis / 中国输血杂志

【Objective】 To retrospectively analyze the detection results of blood donors with HBsAg reactivity to single reagent detected by enzyme-linked immunosorbent assay (ELISA) in our center, so as to provide basis for further consolidating the blood donor team. 【Methods】 Samples of blood donors who had been deferred for at least 6 months due to HBsAg reactivity to sole ELISA assay were collected, and HBsAg ELISA and NAT were further performed. Meanwhile, HBsAg/HBsAb/HBeAg/HBeAb/HBcAb were detected by Roche electrochemiluminescence immunoassay, and the results were statistically analyzed. 【Results】 Among these 51 selected samples, 45 were negative to two assays, 6 were reactive to sole assay, with reactivity-yield rate at 11.76% (6/51). The results of NAT/ECLIA were all negative. For five indicators of hepatitis B virus infection, 23 samples were all negative and 28 were partially positive, mainly anti-HBs, anti-HBc and anti-HBe. 【Conclusion】 The follow-up detection of HBsAg ELISA sole-reagent reactive samples, supplemented with the detection of HBV serological markers, can reduce the number of deferred blood donors, increase the willingness to donate blood again, and protect the rights and interests of blood donors.

Confirmation of HBV infection of HBsAg-negative NAT suspicious sample from blood donors / 中国输血杂志

【Objective】 To explore the HBV infection of initially reactive but discriminatory test non-reactive (NAT suspicious) samples of voluntary blood donors after PANTHER individual nucleic acid testing (ID-NAT) in Tianjin. 【Methods】 From January to August 2021, after routine testing and PANTHER ID-NAT, a total of 66 HBsAg-NAT reactive but discriminatory test non-reactive samples(referred to as NAT suspicious samples) were tested from 69 362 blood samples. Among which, 23 samples were selected by simple random sampling method and enriched by ultra-high speed centrifugation. HBV DNA was detected by supersensitive fluorescence quantification PCR (qPCR)and ID-NAT, and electrochemiluminescence was supplemented for two and half pairs of hepatitis B detection. 【Results】 Among 23 suspicious NAT samples, 14 were confirmed HBV DNA positive by serological and molecular biological tests, and the anti-HBc positive rate of HBV infected individuals was 92.8%. 92.8% (13/14) of the infected individuals were occult hepatitis B virus infection(OBI). A total of 10 samples were detected for viral load by qPCR, of which 5 were quantifiable, with viral load of (11~464) IU/mL and a median of 15.4 IU/mL. 【Conclusion】 60% of the NAT suspicious samples were detected as HBV DNA positive. Anti-HBc testing can exclude most OBI undetectable by NAT, and the sensitivity of NAT should be improved to ensure the safety of blood transfusion.

Verificación del desempeño general del método Elecsys® Chagas en la detección de anticuerpos específicos contra Trypanosoma cruzi / Verification of the general performance of the Elecsys® Chagas method in the detection of specific antibodies against Trypanosoma cruzi

Resumen La enfermedad de Chagas es una parasitosis producida por Trypanosoma cruzi, prevalente principalmente en el continente americano, y observada en regiones no endémicas, producto de viajes y migraciones. El objetivo de este estudio fue comparar el desempeño del ensayo Elecsys® Chagas (Roche Diagnostics Alemania) (ECLIA) para el diagnóstico de la infección chagásica crónica con el método estándar y evaluar su posible empleo en reemplazo del método automatizado existente. Se estudiaron 77 muestras de sueros pertenecientes a pacientes con diagnóstico presuntivo de enfermedad de Chagas, procesadas por los distintos métodos disponibles en la Sección Parasitología del Hospital Muñiz: inmunoensayo quimioluminiscente de micropartículas (CMIA) (Abbott), enzimoinmunoanálisis de adsorción (ELISA) (Wiener) y hemaglutinación indirecta (HAI) (Lab. Lemos S.R.L.). Los resultados de los métodos ELISA y HAI fueron comparados con los obtenidos en la prueba ECLIA, y estos a su vez con el método automatizado disponible. De las muestras analizadas, 22 (28,57%) presentaron IgG anti-T. cruzi y 55 (71,43%) resultaron negativas. Con el método ECLIA se logró un 100% en los parámetros de desempeño, con diferencias en los intervalos de confianza. La razón de verosimilitud positiva y la razón de verosimilitud negativa clasificaron al ensayo como excelente y la potencia global del test apoyó esa afirmación. Los métodos inmunológicos automatizados ayudan a la performance diagnóstica en la etapa crónica de la enfermedad de Chagas, permiten minimizar errores, favorecen la velocidad de emisión de los resultados y, debido a su alta sensibilidad y especificidad, en ciertos escenarios podrían proponerse para usar como única técnica.

Abstract Chagas disease is a parasitosis caused by Trypanosoma cruzi, prevalent mainly in the American continent, and observed in non-endemic regions as a result of travel and migration. The objective of this study was to compare the performance of the Elecsys® Chagas (Roche Diagnostics Alemania) (ECLIA) assay for the diagnosis of chronic Chagas infection with the diagnostic standard, and to evaluate its possible use as a replacement for the existing automated method. A total of 77 serum samples belonging to patients with a presumptive diagnosis of Chagas disease were evaluated, processed by the different methods available in the Parasitology Section of Hospital Muñiz: microparticle chemiluminescent immunoassay (CMIA) (Abbott), enzyme-linked immunosorbent assay (ELISA) (Wiener) and indirect hemagglutination (HAI) (Lab. Lemos S.R.L). The results of the ELISA and HAI methods were compared with those obtained in the ECLIA test, and these in turn with the available automated method. Of the samples analysed, 22 (28.57%) presented IgG anti-T. cruzi and 55 (71.43%) were negative. With the ECLIA method, 100% was achieved in the performance parameters, with differences in the confidence intervals. The positive likelihood ratio and the negative likelihood ratio classify the essay as excellent, and the overall power of the test supports this statement. Automated immunological methods help diagnostic performance in the chronic stage of Chagas disease, allow minimising errors, favour the speed of issuance of results, and due to the high sensitivity and specificity, in certain scenarios, they could be proposed for use as single technique.

Resumo A doença de Chagas é uma parasitose causada pelo Trypanosoma cruzi, prevalente principalmente no continente americano, e observada em regiões não endêmicas em decorrência de viagens e migrações. O objetivo deste estudo foi comparar o desempenho do ensaio Elecsys® Chagas (Roche Diagnostics Alemanha) (ECLIA) para o diagnóstico da infecção crônica de Chagas com o método padrão e avaliar seu possível uso em substituição do método automatizado existente. Foram avaliadas 77 amostras de soro pertencentes a pacientes com diagnóstico presuntivo de doença de Chagas, processadas pelos diferentes métodos disponíveis na Seção de Parasitologia do Hospital Muñiz: imunoensaio quimioluminescente de micropartículas (CMIA) (Abbott), ensaio imunoenzimático de adsorção (ELISA) (Wiener) e hemaglutinação indireta (HAI) (Lab. Lemos S.R.L). Os resultados dos métodos ELISA e HAI foram comparados com os obtidos no teste ECLIA, e estes por sua vez com o método automatizado disponível. Das amostras analisadas, 22 (28,57%) apresentaram IgG anti-T. cruzi e 55 (71,43%) foram negativos. Com o método ECLIA, foram obtidos 100% nos parâmetros de desempenho, com diferenças nos intervalos de confiança. A razão de verossimilhança positiva e a razão de verossimilhança negativa classificam o ensaio como excelente, e a potencia geral do teste conformou essa afirmação. Os métodos imunológicos automatizados auxiliam no desempenho diagnóstico na fase crônica da doença de Chagas, permitem minimizar erros, favorecem a rapidez na emissão dos resultados e, devido à alta sensibilidade e especificidade, em determinados cenários, poderiam ser propostos para uso como técnica única.

Detection and analysis of hepatitis B virus serum markers in children treated in Wuhan Children's Hospital / 公共卫生与预防医学

Objective To investigate the status of hepatitis B virus (HBV) infection in children in Wuhan, and to analyze the expression pattern and distribution of serum markers. Methods Five serum markers of HbsA, HbsAb, HbeAg, HbeAb and HBcAb were detected by electrochemiluminescence immunoassay in 67 027 children aged 0-18 years including inpatients, outpatients, and physical examinees in Wuhan Children's Hospital. SPSS24.0 statistical software was used to analyze the results by age and gender. Results The “all negative” detection rate of all 67,027 children was 18.98%. There was a significant difference in the positive rate of HBcAb between male and female. The positive rate of HBcAb was higher in 0~28 days and 1~12 months group and decreased significantly after 1 year old. The positive rate of HBcAb was 5.02% in 1-14 years old but increased slightly in 15-18 years old. Among HBsAb positive children, the positive rate of HBsAb reached the peak of 95.65% in 1~2 years old group and the lowest of 68.90% in 6~14 years old group, and gradually decreased before 15 years old. Among the children with HBsAb concentration ≥100 IU/L, the proportion of 1~2 years old group was the highest (76.99%), and the proportion of 6~14 years old group was the lowest (40.99%). A total of 20 HBsAb serum marker expression patterns were detected, and the detection rates of “single HBsAb+”, “all negative”, “HBsAb+/HBcAb+”, and “HBsAb+/HBeAb+/HBcAb+” were 71.40%, 18.98%, 4.80% and 4.20%, respectively. Among them, 11 kinds of uncommon expression patterns were detected, and 9 kinds of uncommon expression patterns were detected in neonates, with a detection rate of 1.21%, which was higher than that in other age groups. Among all serological patterns, only the detection rate of “single HBcAb+” showed a statistical difference between male and female. Conclusion The HBV infection rate in all ages of 0~18 years old children in Wuhan is low. “Single HBsAb+” is the main serological pattern, and the concentration distribution of HBsAb is mostly in the range of 100-999 IU /L. There is a high “all negative” detection rate. School-age children should be inoculated with hepatitis B vaccine, which may be beneficial to reduce the risk of infection.

Study on Reentry Evaluation Mode for Blood Donors Used to be HBV Reactive in Jiangsu Province / 中国实验血液学杂志

OBJECTIVE@#To evaluate the risk of reentry in HBV reactive blood donors and feasibility of HBV reentry strategy.@*METHODS@#HBsAg+ or HBV DNA+ donors who had been quarantined for more than 6 months in Jiangsu Province could propose for reentry application. Blood samples were routinely screened by dual-ELISA for HBsAg, anti-HCV, HIV Ab/Ag, and anti- Treponema pallidum and those non-reactive ones were tested by minipool nucleic acid testing (NAT) for three times. To identify occult HBV donors, samples of NAT non-reactive were further tested by electrochemiluminescence immunoassay (ECLIA) for HBV seromarkers (including HBsAg, HBsAb, HBeAg, HBeAb, and HBcAb). Donors of only 4 ECLIA patterns were accepted to reentry, including all 5 HBV seromarkers negative, anti-HBs only but having history of hepatitis B vaccine injection, HBcAb only, HBsAb+ / HBcAb+ with HBsAb more than 200 IU/L. Additionally, the detection rate of HBV infection was compared between routine screening mode and ECLIA, as well as the reentry qualified rate of HBsAg+ and HBV DNA+ blood donors.@*RESULTS@#From Oct. 2016 to Aug. 2019, a total of 737 HBV reactive donors had applied for reentry, including 667 HBsAg+ reactive and 70 HBV DNA+ reactive donors. Among 3 screening methods, the highest HBV detection rate (43.15%, 318/737) was observed on ECLIA, while only 4.75% (35/737) on ELISA and 3.12% (23/737) on NAT, respectively. Among 4 qualified patterns of HBV serological markers, the highest proportion was found in the all negative group (22.90%, 155/677), followed by the group with HBsAb+ only and history of hepatitis B vaccine injection (19.35%, 131/677), and the median concentration of HBsAb was 237.7 IU/L. The unqualified rate of HBV DNA+ donors was 82.86%, which was significantly higher than 47.98% of HBsAg+ donors.@*CONCLUSION@#Routine screening tests merely based on ELISA and NAT could miss occult HBV donors and may not be sufficient for blood safety. HBsAb concentration and vaccine injection history should be included in the evaluation of HBV reactive donors who intend to apply for reentry. There is a relatively larger residual risk of occult HBV infection in blood donors quarantined for HBV DNA reactive.

Establish deferral criterion for HIV serological testing in blood donors / 中国输血杂志

【Objective】 To establish deferral criterion of HIV ELISA (enzyme-linked immunosorbent assay) and electrochemiluminescence immunoassay(ECLIA) by using receiver operating characteristic curve(ROC) method to screen HIV reactive blood donors suitable for entering the re-entry process and improve the management efficiency of reactive blood donors. 【Methods】 The test results of 92 001 blood donors from February to September 2019 were analyzed, and 177 reactive samples were screened by conventional screening mode (twice ELISA and once nucleic acid), supplemented with electrochemiluminescence immunoassay assay (ECLIA), and confirmed by Western blotting (WB). Screening reactive samples were divided into three groups: group A was both serological and nucleic acid reactivity, group B was only serological reactive, and group C was only nucleic acid reactivity. Its efficacy in blood donor classification was assessed by drawing ROC curves with 99% specific corresponding S/CO low values as the deferral criterion of the corresponding serological method. 【Results】 1) A total of 177 HIV reactive samples were detected in conventional mode, including 34 in group A, 142 in Group B and 1 in Group C. The positive predictive value (PPV) was 100%, 0.75% and 100%, respectively. ECLIA detection mode (once ECLIA and once NAT), a total of 67 HIV reactive samples including 34 in group A, 32 in group B and 1 in group C, with positive predictive values of 100%, 3.7% and 100%, respectively.2) The HIV test results showed diversity, with 36 true positive samples including 1 HIV elite controller and 3 early HIV infections (1 HIV ELISA antigen/antibody window and 2 ELISA HIV antibody window), and 32 serological and NAT cases were reactive infections.3) The deferral limit of ELISA 1 and ELISA 2 in conventional screening mode were 20.25 and 9.85, respectively, can screen 97.14% (34/35) of all true positive samples in group A and B, except for one ELISA HIV antibody window (ELISA 2 reactivity). The positive predictive values were 93.94% and 92.85%, respectively. The ECLIA deferral limit of 7.83 can screens all true positive samples in Groups A and B (35/35)in ECLIA mode. The positive predictive value was 94.59%. 【Conclusion】 The establishment of deferral limits in this study can effectively screen HIV-positive blood donors, and the number of screened blood donors is greatly reduced, which is helpful to fine and scientific management of HIV-reactive blood donors. The deferral limit values of different testing reagents are quite different, so each laboratory should choose appropriate testing methods to establish the deferral limit values suitable for the laboratory according to its own testing ability, so as to provide technical support for optimizing the process of returning blood donors to the team.

ECLIA and confirmation results of HIV reactive samples in blood screening / 中国输血杂志

【Objective】 To perform electrochemiluminescence immunoassay (ECLIA) and Western blotting (WB) confirmation tests for HIV reactive samples in blood screening, and analyze the correlation between ELISA (enzyme-linked immunosorbent assay), ECLIA results and confirmed infection, so as to provide data support for the application of ECLIA in blood screening. 【Methods】 177 HIV reactive samples in blood screening testing detected by our laboratory from February to October 2019 were collected, of which 137 were reactiv to isolated ELISA reagent e, 39 to dual ELISA reagent, and 1 in window period. Ten maker-negative samples were randomly selected to undergo ECLIA with the above 177 samples. HIV reactive samples were sent to Centers for Disease Control and Prevention (CDC) for confirmation tests, and the results were analyzed and compared. 【Results】 Among the 177 HIV reactive samples, 66 were ECLIA reactive, 111 negative, and the 10 maker-negative samples remained negative. The sensitivity, specificity, positive predictive value, negative predictive value and total concordance rate of ECLIA were 97.1%, 81.1%, 55%, 99.1% and 84.2%, respectively, showing better performance than that of two ELISA reagents(P0.05). The positive predictive value and specificity were tested by chi-square test, and the difference between ECLIA and reagent 2 was statistically significant (P<0.05). The ECLIA results showed significant correlation with the confirmation results with good consistency(examed by Kappa test). Among the three reagents, ECLIA presented highest accuracy and largest Youden index. 【Conclusion】 ECLIA presents high detection sensitivity, which can improve the detection ability of early HIV infection and shorten the window period of HIV detection, therefore should be popularized in blood screening.

Visualization analysis of lecithin in drugs based on electrochemiluminescent single gold microbeads / 药物分析学报

Fast and high-throughput determination of drugs is a key trend in clinical medicine.Single particles have increasingly been adopted in a variety of photoanalytical and electroanalytical applications,and microscopic analysis has been a hot topic in recent years,especially for electrochemiluminescence (ECL).This paper describes a simple ECL method based on single gold microbeads to image lecithin.Lecithin reacts to produce hydrogen peroxide under the successive enzymatic reaction of phospholipase D and choline oxidase.ECL was generated by the electrochemical reaction between a luminol analog and hydrogen peroxide,and ECL signals were imaged by a camera.Despite the heterogeneity of single gold microbeads,their luminescence obeyed statistical regularity.The average luminescence of 30 gold microbeads is correlated with the lecithin concentration,and thus,a visualization method for analyzing lecithin was established.Calibration curves were constructed for ECL intensity and lecithin concentra-tion,achieving detection limits of 0.05 mM lecithin.This ECL imaging platform based on single gold microbeads exhibits outstanding advantages,such as high throughput,versatility and low cost,and holds great potential in disease diagnostics,environmental monitoring and food safety.

Analysis of NAT non-reactive results implicated in HBsAg ELISA reactive blood donors by multi-assays / 中国输血杂志

【Objective】 To investigate NAT non-reactive results implicated in HBsAg ELISA reactive voluntary blood donors in Shenzhen. 【Methods】 HBsAg ELISA+ but NAT-blood samples were collected, and HBsAg was further retested by TRFIA, Roche ECLIA and neutralization test. HBV DNA of individual donation was detected by commercial Roche MPX and Uultrio Elite, and virus nucleic acid was extracted via 2.5 mL. Molecular characterizations of HBsAg+ /NAT-samples were determined by quantitative polymerase chain reaction(qPCR) and nested PCR amplifification of the precore and core promoter regions and HBsAg(S) region. HBV serological markers were detected, and the samples with suspicious results were followed up and detected by multi-assay. 【Results】 Among 67 602 samples, 73(0.11%) HBsAg ELISA+ and NAT-blood samples were enrolled in the study. 15(20.5%, 15/73) were confirmed HBsAg+ by TRFIA, ECLI and five alternative DNA assays, and the other 2(2.7%, 2/73) were further identified as HBsAg+ by follow-up study. In 17 confirmed HBsAg+ samples, the viral loads ranged undetectable to 378 IU/mL, with the median of 10.1 IU/mL. Weak correlation was found between HBsAg and HBV DNA load(R2=0.394 4). 【Conclusion】 Some Hepatitis B virus infected blood samples may miss even with different HBsAg assays. Multi-assays with high sensitivity should be combined for blood screening to ensure blood safety..The inconsistent results should be followed up and further tested for hepatitis B serological markers to assist the confirmation.

Avaliação comparativa de dosagem do marcador tumoral CA 15-3 em cadelas hígidas ou com neoplasia mamária / Comparative evaluation of tumor marker CA 15-3 dosage in dogs, healthy or with breast cancer

O antígeno CA 15-3 é uma proteína presente no soro utilizado no acompanhamento de mulheres com câncer de mama, essencialmente na detecção de metástases. Os objetivos deste estudo foram avaliar a efetividade e a viabilidade da utilização do marcador tumoral CA 15-3 em cadelas, comparando-se os valores do marcador entre cadelas sem e com neoplasia mamária, avaliando-se alterações nos valores do marcador após a mastectomia, e suas correlações entre o tipo histológico. Foi realizada a quantificação sérica do marcador tumoral CA 15-3 (teste de eletroquimioluminescência), em vinte cadelas hígidas (grupo controle) e vinte cadelas com neoplasia mamária (grupo teste). Os animais com neoplasia tiveram a dosagem do marcador realizada antes e 10 dias após a mastectomia. Ainda, foi realiza a citologia vaginal no momento da mastectomia e foram estabelecidos três grupos de acordo com a fase estral de cada cadela, Diestro, Proestro e Anestro. As massas tumorais foram encaminhadas para exame histopatológico. A avaliação dos dados de citologia vaginal entre os grupos Diestro, Proestro e Anestro pelo teste de ANOVA não demonstrou diferença estatística significativa entre os valores encontrados. E na análise para a comparação dos valores do marcador tumoral com os tipos histológicos de neoplasias, divididas em dois grupos, benignas e malignas, utilizando o teste de Mann-Whitney Rank Sum Test, o teste não demonstrou diferença estatística significativa visto que p>0,05. Os valores encontrados do marcador no grupo controle foram uma média de 0,19+0,39 U/mL, no grupo pré-mastectomia 1,56+0,39 U/mL e pós-mastectomia 0,66+0,27 U/mL. Em análise estatística com a comparação de grupo pré e pós-mastectomia, e do grupo controle com o grupo pré e pós-mastectomia observou-se significância com p< 0,005. Assim, observou-se diferença nos valores do marcador antes e depois da remoção cirúrgica da neoplasia, sugerindo seu possível uso como controle de crescimento tumoral pós-mastectomia individual. Porém há muita variação dos resultados nos diferentes métodos existentes, e não há ainda um padrão dos valores de referência para cada método, sendo necessários mais estudos sobre o uso dos marcadores.(AU)

The CA 15-3 antigen is a protein present in the serum, used to monitor women with breast cancer, mainly in metastatic disease detection. The objective of this study was to evaluate the effectiveness and feasibility of the CA 15-3 tumor marker in dogs, comparing the marker values between dogs with or without breast cancer, to estimate changes in marker values after mastectomy, and their correlation between the histological types. Serum quantification of the tumor marker CA 15-3 (electrochemiluminescence test) was performed in twenty healthy bitches and twenty others with mammary neoplasia. Bitches with cancer had the content of the tracer performed before and 10 days after mastectomy. The vaginal cytology was performed at the moment of the mastectomy, dividing the animals into three different groups (diestrus, proestrus and anestrus). All the mammary tumors were examined histopathologically. The evaluation of the vaginal cytology data of the groups Diestro, Proestro and Anestro by the ANOVA test did not show a statistically significant difference between the values ​​found. In the analysis histological types of tumor marker values of neoplasms, divided into two groups, benign and malignant, using the Mann-Whitney Rank Sum Test, there was no statistical significant difference at p>0.05. The values of the marker in the control group had an average of 0.19+0.39 U/mL, of the pre-mastectomy group 1.56+0.39 U/mL, and of the post-mastectomy group 0.66+0.27 U/mL. The statistic was performed comparing groups pre- and post-mastectomy, and the control group with group pre- and post-mastectomy with a statistical significance p< 0.005 in both tests. There was a difference of marker values ​​before and after surgical removal of the neoplasia, suggesting its possible use in post-mastectomy tumor control. But exist variation of results with the different existing methods, and there will be still a standard reference value for each method.(AU)

Comparison of Four Automated Carcinoembryonic Antigen Immunoassays: ADVIA Centaur XP, ARCHITECT I2000sr, Elecsys E170, and Unicel Dxi800

BACKGROUND: Carcinoembryonic antigen (CEA) is one of the tumor markers available for evaluating disease progression status after initial therapy and monitoring subsequent treatment modalities in colorectal, gastrointestinal, lung, and breast carcinoma. We evaluated the correlations and differences between widely used, automated CEA immunoassays at four different medical laboratories. METHODS: In total, 393 serum samples with CEA ranging from 3.0 to 1,000 ng/mL were analyzed on ADVIA Centaur XP (Siemens Diagnostics, Tarrytown, NY, USA), ARCHITECT i2000sr (Abbott Diagnostics, Abbott Park, IL, USA), Elecsys E170 (Roche Diagnostics, Indianapolis, IN, USA), and Unicel DxI800 (Beckman Coulter, Fullerton, CA, USA), and the results were compared. Deming regression, Passing-Bablok regression, and Bland-Altman analyses were performed to evaluate the data correlation and % differences among these assays. RESULTS: Deming regression analysis of data from Elecsys E170 and UniCel DxI800 showed good correlation (y=3.1615+0.8970x). According to Bland-Altman plot, no statistically significant bias (−1.78 ng/mL [95% confidence interval: −4.02 to 0.46]) was observed between Elecsys E170 and UniCel DxI800. However, the relative differences of CEA concentrations between assays exceeded the acceptable limit of 30%. Regarding the agreement of positivity with cut-off value 5.0 ng/mL, ARCHITECT i2000sr and Elecsys E170 showed the highest agreement (95.2%), whereas ADVIA Centaur XP and ARCHITECT i2000sr showed the lowest agreement (70.7%). CONCLUSIONS: Agreements between automated CEA immunoassays are variable, and individual CEA concentrations may differ significantly between assays. Standardization of serum CEA concentrations and further harmonization are needed.

A comparative study of two methods for detecting procalcitonin / 国际检验医学杂志

Objective To use cyclic amplified fluorescence immunoassay method and electrochemiluminescence immunoassay method for quantitative detection of procalcitonin (PCT),and to evaluate the consistency of the test results.Methods With the method of electrochemiluminescence used as the contrast method and the cyclic enhanced fluorescence immunoassay method used as experimental method,samples of 219 hospitalized patients were measured in two ways.The results were divided into three groups:the serum group (Core serum group) and the micro blood group (Core micro blood group) which were detected in cyclic amplified fluorescence immunoassay method and the serum group (Roche serum group) which was detected by electrochemiluminescence immunoassay method.The data of three groups were compared with each other in paired t test,and correlation analysis,the relative sensitivity,the relative specificity,and Jorden index at the medical decision level (0.5 ng/mL and 2.0 ng/mL) were calculated and the Kappa Consistency Test was calculated.Results There were no statistical differences in three groups (P＞0.05).The Core serum group was positively correlated with the Roche serum group (r =0.993,P＜0.01).The linear regression equation was Y =-0.061+1.041X(0.04≤X≤60).The Core micro blood group was positively correlated with the Roche serum group(r=0.989,P＜0.01).The linear regression equation was Y=0.022+1.023X(0.04≤X≤60).The Core micro blood group was positively correlated with the Core serum group (r=0.986,P＜0.01).The linear regression equation was Y=0.129+0.973X(0.04≤X≤60).The relative sensitivity of the three comparison groups was greater than 92％ and the relative specificity was greater than 95％ at the medical decision level (0.5 ng/mL and 2.0 ng/mL),and the Jorden index and Kappa values were greater than 0.9.It indicated a better consistency.Conclusion Cyclic amplified fluorescence immunoassay and electrochemiluminescence immunoassay detection results were very consistent,which meet the clinical testing requirements.

Amplification Effect of CdS Quantum Dots on Electrogenerated Chemiluminescence of Ru(bpy)32+and Its Application in Determination of Catechol / 分析化学

The effect of CdS quantum dots (QDs) on the electrochemiluminescence (ECL) signal of Ru(bpy)32+ was studied. It was found that CdS QDs could enhance the anodic ECL of Ru(bpy)32+ by 4 times. The sensitization mechanism was discussed and the influence factors including concentrations of Ru (bpy)32+ and CdS QDs, pH of solution and scan rate on ECL intensity were investigated. On the basis of quenching effect of catechol on the ECL signal of CdS QDs-Ru(bpy)32+,a system for sensitive determination of catechol was established with a detection limit of 5.5 nmol/L (S/N=3). This method was applied to the detection of catechol in tea sample with satisfactory results.

Análisis de técnicas treponémicas y no treponémicas en el tamizaje serológico de sífilis / Analysis of treponemical and non treponemical techniques for syphilis blood bank screening

Introducción: las infecciones producidas por el Treponema pallidum causante de la sífilis han alcanzado gran trascendencia entre las enfermedades infecciosas transmitidas por transfusión (ITT) y un nuevo repunte a nivel mundial. Debido a las diferentes etapas clínicas que presenta la enfermedad, el desempeño de cada prueba de detcción varía y se limita. Así, la elección de una técnica de tamizaje adecuada se convierte en un punto fundamental para garantizar la calidad y seguridad de cada hemocomponente despachado. Objetivo: analizar y evaluar la eficacia de cuatro técnicas de tamizaje serológico. Métodos: se realizó un estudio comparativo transversal con 1 376 muestras seleccionadas al azar a nivel nacional en el mes de diciembre 2015. Se compararon las técnicas de inmunocromatografía (IC), floculación (VDRL), electroquimioluminiscencia (ECLIA) y microelisa. Se analizó la eficacia individual de cada técnica y comparativa con respecto a la gold standard (FTA-ABS) utilizando para ello el coeficiente de correlación Cohen-Kappa (К). Resultados: las cuatro pruebas presentaron un nivel de concordancia del 98,67 por ciento. Del total de resultados discrepantes el 63,16 por ciento fueron generados por VDRL, la cual al mismo tiempo demostró tener el menor rendimiento (k=0,14) y alcanzó los valores más bajos de sensibilidad (s=69 por ciento) y especificidad (e=45 por ciento), lo cual contrastó con la IC que demostró el mayor rendimiento (k=0,863, s=100 por ciento, e=0,8 2 por ciento), seguido de la ECLIA (k=0,801, s=96 por ciento, e=0,82 por ciento) y el microelisa (k=0,711, s=100 por ciento, e=0,64 por ciento). Conclusión: se evidencia la necesidad de utilizar pruebas de nuevas tecnologías en el tamizaje serológico de sífilis y remplazar el uso de VDRL, ya que una correcta selección asegura el descarte de hemocomponentes en el número correcto (evitando grandes pérdidas de sangre y de dinero) y, en especial se asegura la calidad sanitaria de cada hemocomponente(AU)

Introduction: Infections produced by Treponema pallidum, which causes syphilis, have reached an important high level among infectious transmitted by transfusion (ITT). Due to the different clinical stages of the disease, the performance of each test is varied and limited. Thus, the choice of a suitable screening technique becomes a fundamental point in a blood bank, to guarantee the quality and safety of each blood component dispatched. Objective: The aim of this study was to analyze and evaluate the performance of four serological screening techniques. Methods: A cross-sectional study was conducted with 1 376 randomly selected samples nationwide in December 2015. The techniques used were immunochromatography (IC), flocculation (VDRL), electrochemiluminescence (ECLIA) and microelisa, and we compared the performance of each one and with respect to the gold standard (FTA-ABS) by using the Cohen-Kappa correlation coefficient (K). Results: The four tests had a concordance level of 98.67 percent. Of the total discrepant results the 63.16 percent were generated by VDRL, which at the same time showed the worst performance (k=0,14) and reached the lowest values ​​of sensitivity (s=69 percent) and specificity (e=45 percent). That contrasted with IC, which showed the best performance (k=0,883, s=100 percent, e=82 percent), followed by ECLIA (k=0,801, s=96 percent, e=0,82 percent) and microelisa (k=0,711, s=100 percent, e=0.64 percent). Conclusion: There is a necessity to use tests with new technologies in the serological screening of syphilis and to replace the use of VDRL in a blood bank, due to a correct selection, ensures the quality and the disposal of blood components in the correct number avoiding great losses of blood and money(AU)

Ultrasensitive Determination of L-Cysteine Based on Its Enhancement to Electrochemiluminescence of CdS Quantum Dots with Cd2+Rich Surface / 分析化学

A novel electrochemiluminescence ( ECL) method for the determination of L-cysteine ( L-Cys) was established. water-soluble CdS quantum dots ( QDs) with Cd2+rich surface were synthesized via a controllable one-poe approach. The mercapto group in L-cysteine molecule can specifically interact with excessive Cd2+on the surface of CdS QDs, resulting in enhancement of ECL intensity of the CdS QDs, which can be used for the detection of L-Cys. Under the optimal experimental conditions, the enhancement of ECL intensity was linear with the concentration of L-Cys in the range of 5. 0×10-9-1. 0×10-5 mol/L. The limit detection of (S/N=3) was 1. 2×10-9 mol/L. In comparison with other methods for detecting L-Cys, this method is more simple and selective, and can be applied to detect L-Cys in real sample with satisfactory results.

Screening analysis of positive thyroid autoantibody in waterborne high iodine ar-ea healthy people / 中国免疫学杂志

Objective:To investigate the correlation between positive rate of thyroid autoantibodies in healthy people and thy -roid dysfunction.Methods:Fasting blood from 3218 healthy examined people in Cangzhou were collected and the serum was separa -ted.Automatic electrochemiluminescence immunoassay systems and reagents were used to determine the concentration of thyroid stimu -lating hormone(TSH),free triiodothyroninthyroid(FT3),free thyroxine(FT4),peroxidase antibody(TPOAb)and thyroglobulin antibody ( TgAb ) .TPOAb>34 U/ml and TgAb>115 U/ml was positives.Statistical analysis of test results .statistica analysis of test reults.Results:The positive rate of thyroid autoantibodies of tested population was 16.19%.The positive rates of TPOAb and TgAb were 14.57%,12.74%separately.The detection rate of TPOAb and TgAb was 11.12%in tested population.The positive rate of TPO-Ab and TgAb and TPOAb+TgAb were 6.92%,5.68%,5.03%separately in 1532 male subjects and were 21.53%,19.16 ,16.67%separately in 1686 female subjects,which were significantly higher in female group than that in male group (P<0.001).They gradually increased with age and reached a peak above 70 years old in female group and in 50-59 in male group.The positive rate and OR of thy-roid autoantibodies in hyperthyroidism and subclinical hyperthyroidism and in hypothyroidism and subclinical hypothyroidism and in hy -pothyroidism and subclinical hypothyroidism were statistically significant .Conclusion:The positive incidence of thyroid autoantibodies is higher in healthy people of Cangzhou .It is essential to follow-up these people of normal thyroid function with positive autoantibodies in order to facilitate prevention and early diagnosis and treatment of thyroid disease .

Clinical analysis of prediction for recurrence of gynecological tumors through serum HE4, CA72-4 and VEGF levels / 中国医学装备

Objective:To explore the predictive value of human serum epididymis protein 4 (HE4), carbohydrate antigen 72-4 (CA72-4) and vascular endothelial growth factor (VEGF) for the recurrent risk of gynecological tumor. Methods: A total of 142 patients with gynecologic malignant tumors were divided into the observation group, and all of them were followed up, and their recurrence rate within 2 years after operation was calculated. At the same time, 50 healthy women were divided into control group. The peripheral venous blood of all subjects were collected to test serum HE4 and VEGF levels by using enzyme-linked immunosorbent assay (ELISA). The serum CA72-4 was detected by using Roche electrochemiluminescence immunoassay. Three indicators of two groups were compared. Results: Before treatment, the serum HE4, CA72-4 and VEGF levels of the observation group were significantly higher than those of the control group (t=58.971,t=26.795,t=42.021;P<0.01). And the positive rate of HE4, CA72-4 and VEGF of the gynecological tumor group were significantly higher than those of the control group (x2=50.061, x2=37.596,x2=43.765,P<0.01). Within post-operative 2 years, there were 84 cases were recurrence in observation group. And the HE4, CA72-4 and VEGF of recurrent patients were significantly higher than that of non-recurrent patients (t=53.075,t=22.211,t=55.948,P<0.01).The sensitivity and negative predictive value of the combined detection of 3 indicators were significantly larger than that of single detection of CA72-4 (x2=8.537,x2=5.345, P<0.05).Conclusion: Patients with gynecological malignant tumor have high expression of serum HE4, CA72-4 and VEGF and the combined detection of 3 indexes possessed more sensitive, and it has greater predictive value for the recurrent risk of gynecologic malignant tumor.

Progress of Metal Nanoclusters-based Electrochemiluminescent Analysis / 分析化学

In the past ten years, the development of electrochemiluminescent ( ECL ) analytical methods based on various types of nanostructures has become a research hotspot. Nanocluster, an intermediate between molecules and conventional nanoparticles, is renowned for its luminescent feature. The first report on ECL for nanoclusters can be traced back to 2009 . Here we summarized the main research progresses since 2011 . Firstly, the preparation of ECL-related nanoclusters was briefly introduced. Then, the mechanisms and applications of ECL by nanoclusters were described. To improve ECL performances, two main strategies, i. e. , nanostructure-based ECL enhancement and biological signal amplification were proposed. Besides, the nanoclusters as the energy transfer receptors in ECL systems were also discussed. In prospect part, the future development of ECL by nanoclusters was considered. We believed that the synthesis of high quality nanoclusters, the reveal of ECL structure-activity relationships, the rationale design and application of near-infrared ECL, and the role of ECL in the interdisciplinary research were the main problems we faced in the future.

An Electrochemiluminescent Method to Detect A Dipeptide Related to Diabetes / 分析化学

In this work, a simple and fast approach for dipeptide detection was developed. AuNPs were decorated onto the surface of indium tin oxide ( ITO ) glass to serve as the working electrode to trigger the electrochemiluminescence ( ECL) of luminol. The property of this electrode was characterized by transmission electron microscopy ( TEM ) , scanning electron microscopy ( SEM ) , electrochemistry and spectroscopic method. Under the optimum conditions, the dipeptide His-Ala could be detected within a linear range from 2. 44×10-11 mol/L to 1. 22×10-7 mol/L, with a detection limit of 2. 42×10-12 mol/L (S/N=3). In human body, the glucagon-like peptide 1(GLP-1) might lose activity during degradation under the enzymatic action of dipeptidyl peptidase IV (PDD-IV), meanwhile release same concentrated His-Ala dipeptide. Thus, the detection of His-Ala dipeptide was of great significance for investigation of diabetes not only for understanding the relation between GLP-1, PDD-IV and its inhibitor, but also the drug discovering because of its potential availability as the target to control the blood GLP-1 level of type II diabetics.

A Magnetic Graphene and Paper-based Electrochemiluminescence Sandwich Immunoassay / 分析化学

Based on the electrochemiluminescence and magnetic suspension immunoassay strategy, a new magnetic graphene and paper-based screen-printed electrode ( SPE ) electrochemiluminescence sandwich immunoassay was developed by combination of the unique physical and chemical properties of magnetic graphene and the advantages such as low cost and low-volume sample consumption of paper-based SPE. Taking human IgG as the model analyte, EDC/NHS method was used to couple capture antibody ( Ab1 ) and magnetic graphene, and direct labeling method was used to label signal antibody ( Ab2 ) with Ru NHS ester. Nonspecific adsorption was highly reduced by the magnetic suspension sandwich immunoassay strategy, and the concentration information of the analyte was obtained by paper-electrochemiluminescence detection. Experimental study of immobilization and labeling effect of Ab1 and Ab2 showed that the magnetic graphene not only improved the load of immune substances, but also promoted the electron transfer. The developed magnetic suspension and paper-based electrochemiluminescence immunoassay could realize the quantitative detection of IgG and had certain application prospect in low cost and rapid immune detection field.