Chemiluminescent Enzyme Immunoassay Research Articles

Incidence rates of hepatitis C virus infection among blood donors in Japan: a nationwide retrospective cohort study.

The classification of many new cases of hepatitis virus infection as overt hepatitis does not reflect the true incidence of infection because the disease takes an asymptomatic course in some cases. In this retrospective cohort study, we aimed to estimate the incidence rates of new hepatitis C virus (HCV) infections among the blood donors. A 5-year retrospective cohort study was conducted to estimate the incidence rates by using the medical records of the blood donors between 2008 and 2013 for HCV infection. HCV seroconversions were investigated using a chemiluminescent enzyme immunoassay and then confirmed by nucleic acid amplification tests. The incidence rate of HCV infection was 0.40 per 100,000 person-years (95% confidence interval, 0.27-0.57) for HCV RNA seroconversion only and 7.32 per 100,000 person-years (95% confidence interval, 6.73-7.95) if either HCV RNA or anti-HCV seroconversion were taken into consideration. No significant difference of new HCV infections was found between the sexes. The incidence rate of HCV infection of this study was lower than that detected in a previous 1994-2004 study in which HCV incidence was 1.86 per 100,000 person-year, which reflects the presence of an effective blood screening system and health strategies targeting hepatitis control and prevention.

A novel role for zinc transporter 8 in the facilitation of zinc accumulation and regulation of testosterone synthesis in Leydig cells of human and mouse testicles

ObjectiveZinc is intimately involved in testosterone production. Zinc transporter 8 (ZnT8) is found to be localized in insulin secretory granules as a β-cell specific Zn transporter. The effect of ZnT8 and related zinc accumulation in steroidogenesis, however, is still unknown. The present study aimed to explore whether ZnT8 plays a role in the facilitation of zinc accumulation and regulation of testosterone synthesis in testicles. MethodsLeydig cells were isolated from the testicles of human, CD-1 suckling and ZnT8-KO mice. Zn accumulation in mitochondria was induced by hCG stimulation. Transfection of hZnT8-EGFP and RNA interfere of mZnT8 were done in MLTC-1 cells. ZnT8 expression and its co-localization with steroidogenic acute regulatory (StAR) protein were analyzed with RT-PCR, Western blot and dual-fluorescent staining protocols. Serum testosterone levels in mice were determined with chemiluminescent enzyme immunoassay. ResultsZnT8 was found to be presented in Leydig cells and up-regulated in suckling mouse Leydig cells and MLTC-1 cells after hCG administration, by which zinc accumulation occurred in mitochondria. ZnT8 gene silencing or knockout inhibited stimulated progesterone and testosterone production, reduced stimulated zinc accumulation and down-regulated phosphorylated steroidogenic acute regulatory (StAR) expression in Leydig cells. Furthermore, an inhibitor (H89) of PKA blocked hCG-stimulated progesterone caused by ZnT8 over-expression and zinc treatment. ConclusionThe present study provided the first evidence that ZnT8 transports Zn into Leydig cell mitochondria with gonadotropin stimulation and suggests that ZnT8 may play a role in testosterone production via the PKA signaling pathway.

Performance of Hepatitis B Core-Related Antigen Versus Hepatitis B Surface Antigen and Hepatitis B Virus DNA in Predicting HBeAg-positive and HBeAg-negative Chronic Hepatitis.

BackgroundWe examined changes in hepatitis B core-related antigen (HBcrAg) during the four sequential phases of chronic hepatitis B virus (HBV) infection: hepatitis B e antigen (HBeAg)-positive chronic infection (EPCI) and hepatitis (EPCH), followed by HBeAg-negative chronic infection (ENCI) and hepatitis (ENCH). We compared the performance of serum HBcrAg, hepatitis B surface antigen (HBsAg), and HBV DNA in predicting EPCH and ENCH.MethodsWe enrolled 492 consecutive patients: 49 with EPCI, 243 with EPCH, 101 with ENCI, and 99 with ENCH. HBcrAg was detected by chemiluminescent enzyme immunoassays. HBsAg and HBeAg were detected by chemiluminescent microparticle immunoassays. HBV DNA was detected by real-time PCR. Predictive performance of HBcrAg, HBsAg, and HBV DNA was evaluated using ROC curves.ResultsAreas under ROC curves (AUCs) of HBcrAg, HBsAg, and HBV DNA for predicting EPCH were 0.738, 0.812, and 0.717, respectively; optimal cutoffs were ≤1.43×105 kU/mL, ≤1.89×104 IU/mL, and ≤3.97×107 IU/mL, with sensitivities and specificities of 66.3% and 77.6%, 65.0% and 93.9%, and 60.5% and 79.6%, respectively. AUCs of HBcrAg, HBsAg, and HBV DNA for predicting ENCH were 0.887, 0.581, and 0.978, respectively; optimal cutoffs were >26.8 kU/mL, >2.29×102 IU/mL, and >8.75×103 IU/mL, with sensitivities and specificities of 72.7% and 95.1%, 86.9% and 39.6%, and 89.9% and 92.1%, respectively.ConclusionsHBsAg and HBV DNA were the best predictors of EPCH and ENCH, respectively. HBcrAg is an important surrogate marker for predicting EPCH and ENCH.

Presepsin: A Anew Marker for Early Diagnosis of Septicemia

AbstractBackground: Sepsis is a life-threatening condition that arises when the body's response to an infection and injures of its own tissues and organs. The fatality rate of patients with sepsis has remained as high as 30-60% despite advances in antibiotic therapy and modern life support.Aim of Study: Early and rapid diagnosis of septicemia by presepsin and comparing its level to the blood culture technique as a gold standard for diagnosis of septicemia.Patients and Methods: This is a case control study. Forty five (45) post traumatic patient admitted to Intensive Care Unit (ICU) in Assiut University Hospitals who met one or more of the inclusion criteria (according to American College of Chest Physicians ACCP)/Society of Critical Care Medicine (SCCM), in addition to 15 apparently healthy subject as control group matching for age and sex. PATHFAST® Presep-sin is a Chemiluminescent Enzyme Immunoassay (CLEIA) for the quantitative measurement of presepsin concentration in whole blood or plasma were used.Results: In this study, the reference limits of presepsin were 57-337pg/ml, the sensitivity and specificity of presepsin were 97.1% and 63.6% respectively in comparing to the sensitivity and specificity of WBCs was 63% and 11% respec-tively and the sensitivity and specificity of hsCRP was 64% and 63% respectively. The diagnostic value in the present study were set (879.73±403.9pg/ml) for SIRS group, (1011.19 ±219.3pg/ml) for sepsis group, and (1621.1±429.95) for severe sepsis group. The presepsin level was significantly increased in patients with positive blood culture (sepsis and severe sepsis group) comparing to patient with negative blood culture (SIRS group) at the time of admission and after 3 day follow-up. Also a significant increase in presepsin levels was observed compared to controls in the lowest to highest groups of sepsis severity during the first 3 day of intensive care treatment (p <0.001), which was not observed for WBCs and hsCRP.Conclusion: The presepsin has a higher sensitivity and specificity in early diagnosis of sepsis as a biomarker, and its concentrations is not only useful for diagnosis of sepsis and evaluating its severity, but also used as a predictor for the prognosis of sepsis.

Clinical evaluation of a novel and highly sensitive immunoassay for anti-hepatitis B core antigen using a fully automated immunochemical analyzer.

Recently, the measurement of hepatitis B surface antigen and anti-hepatitis B core antigen (HBcAb) and/or anti-hepatitis B surface antigen has been recommended before various therapies to identify patients at risk of hepatitis B virus (HBV) reactivation. However, a recent study reported that HBV reactivation occurred in HBcAb-negative patients, indicating that it is challenging to identify patients with a history of HBV infection using conventional HBcAb reagent. We developed a highly sensitive HBcAb (HBcAb-HS) assay for reducing the risk of HBV reactivation. The HBcAb-HS assay is an automated chemiluminescent enzyme immunoassay system, which is suitable for clinical use. The cut-off was set at 0.020IU/mL from the distribution patterns of HBcAb-negative specimens, and we evaluated the performance of this assay compared with conventional reagents. This new assay showed a 27-81-fold greater sensitivity than conventional HBcAb reagents; the quantified measurement range was from 0.005IU/mL to 1.500IU/mL, and it showed excellent quantitative performance and correlated well with two conventional assays, using the HBcAb-positive specimens. Moreover, it showed 100% specificity for the 469 purchased HBcAb-negative specimens. Notably, this newly developed HBcAb-HS assay showed positivity in the preserved specimens before HBV reactivation, for which conventional HBcAb reagents gave negative results, and the HBcAb-HS assay could detect the lower HBcAb levels even after intensive immunosuppressive therapies, including autologous hematopoietic stem cell transplantation. The clinical efficacy of the newly developed, highly sensitive HBcAb assay would enable the identification of patients at risk of HBV reactivation more accurately.

Automation vs. Experience: Measuring Alzheimer's Beta-Amyloid 1-42 Peptide in the CSF.

Cerebrospinal fluid (CSF) biomarkers can enhance the early and accurate etiologic detection of Alzheimer’s disease (AD) even when symptoms are very mild, but are not yet widely available for clinical testing. There are a number of reasons for this, including the need for an experienced operator, the use of instruments mostly reserved for research, and low cost-effectiveness when patient samples do not completely fill each assay plate. Newer technology can overcome some of these issues through automated assays of a single patient sample on existing clinical laboratory platforms, but it is not known how these newer automated assays compare with previous research-based measurements. This is a critical issue in the clinical translation of CSF AD biomarkers because most cohort and clinicopathologic studies have been analyzed on older assays. To determine the correlation of CSF beta-amyloid 1–42 (Aβ42) measures derived from the automated chemiluminescent enzyme immunoassay (CLEIA, on Lumipulse® G1200), a bead-based Luminex immunoassay, and a plate-based enzyme-linked immunoassay enzyme-linked immunosorbent assay (ELISA), we analyzed 30 CSF samples weekly on each platforms over 3 weeks. We found that, while CSF Aβ42 levels were numerically closer between CLEIA and ELISA measurements, levels differed between all three assays. CLEIA-based measures correlated linearly with the two other assays in the low and intermediate Aβ42 concentrations, while there was a linear correlation between Luminex assay and ELISA throughout all concentrations. For repeatability, the average intra-assay coefficient of variation (CV) was 2.0%. For intermediate precision, the inter-assay CV was lower in CLEIA (7.1%) than Luminex (10.7%, p = 0.009) and ELISA (10.8%, p = 0.009), primarily due to improved intermediate precision in the higher CSF Aβ42 concentrations. We conclude that the automated CLEIA generated reproducible CSF Aβ42 measures with improved intermediate precision over experienced operators using Luminex assays and ELISA, and are highly correlated with the manual Aβ42 measures.

Clinical evaluation of hepatitis B core-related antigen in chronic hepatitis B and hepatocellular carcinoma patients

BackgroundHepatitis B core-related antigen (HBcrAg) has been revealed as an important marker of Hepatitis B virus (HBV) infection recently. We aimed to evaluate the HBcrAg assay for indication of HBV loads in chronic hepatitis B (CHB) and hepatocellular carcinoma (HCC) patients and assess the association between HBcrAg/cccDNA and HCC recurrence. MethodsHBcrAg was measured by chemiluminescence enzyme immunoassay. Intrahepatic covalently closed circular DNA (cccDNA) was measured by real-time PCR with TaqMan fluorescent probes based on liver specimens from 89 HCC patients. ResultsHBcrAg correlated positively with HBV DNA irrespective of HBeAg status. Both HBcrAg and HBV DNA were associated with cccDNA in patients with elevated serum HBV DNA (>4 log IU/mL). In patients with non-elevated HBV DNA (≤4 log IU/mL), no relationship between HBV DNA and cccDNA was observed, but we still documented a modest correlation between HBcrAg and cccDNA. Finally, the recurrence-free survival rates were significantly lower in HCC patients with high intrahepatic cccDNA and serum HBcrAg levels than those with low cccDNA/HBcrAg levels (p = 0.035, p = 0.003 respectively). ConclusionsHBcrAg not only can serve as a biomarker to assess HBV loads in patients as well as provide a good method for monitoring cccDNA in HCC, but also can be used as a good prognostic predictor for HCC patients.

Development of peptide-based chemiluminescence enzyme immunoassay (CLEIA) for diagnosis of dengue virus infection in human

Dengue is the most prevalent mosquito-borne viral disease in tropical and subtropical regions worldwide. Since its clinical symptoms are non-specific and easily mistaken as other kinds of infection, laboratory diagnosis is required to confirm dengue infections. In this study, ten peptides (E1-E10) from the envelope protein of dengue virus (DENV) were first identified using bioinformatic tool. The screened peptides were then synthesized for the peptide-based chemiluminescence enzyme immunoassay (CLEIA). Two peptides, E1 and E7, were found as the best candidate antigen and therefore used as downstream application in the development of low-cost peptide-based anti-DENV immunoglobulin M antibodies (IgM) indirect CLEIA. 176 serum samples were used to study the presence of anti-DENV IgM antibodies to evaluate the diagnostic ability of IgM-CLEIA. Receiver operating characteristic curve (ROC) was used to estimate the diagnostic cut-off value. The sensitivity and the specificity reached 82.5% and 94.6% respectively when peptide E1 was used, but declined to 79.2% and 92.9% respectively when peptide E7 was used. Therefore, the combination of E1 and E7 was used to improve the sensitivity and the specificity to 85.0% and 96.4% respectively in 1.5 h assay time, providing a potentially practical use for the diagnosis of DENV infections in patients' serum.

Comparison of whole‐blood tacrolimus concentrations measured by different immunoassay systems

Different measured values for tacrolimus were obtained with different automated immunoassays. We aimed to examine the differences in the blood tacrolimus concentrations measured by the major immunoassay systems commercially available in Japan. Whole-blood samples from 118 patients were assayed by 3 commercial assays: chemiluminescent enzyme immunoassay (CLIA), affinity column-mediated immunoassay (ACMIA), and enzyme-multiplied immunoassay technique (EMIT). Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used for reference. The correlation coefficient of immunoassay vs LC-MS/MS was excellent for ACMIA (.83) and CLIA (.81) and good for EMIT (.71). The mean error was negative for ACMIA and positive for CLIA and EMIT. The mean absolute error and root-mean-square error were almost the same for ACMIA and CLIA and lower than those for EMIT. The ACMIA and CLIA yield considerably better results than the EMIT for monitoring blood tacrolimus concentrations.

Prolactin selectively transported to cerebrospinal fluid from blood under hypoxic/ischemic conditions.

AimThe aim of this study was to determine and to verify the correlation between the amount of prolactin (PRL) levels in the blood and in the cerebrospinal fluid (CSF) by various causes of death as an indicator for acute hypoxia in autopsy cases. It is to confirm the cause of the change in prolactin level in CSF by in vitro system.Materials and methodsIn autopsy materials, the PRL levels in blood from the right heart ventricle and in the CSF were measured by chemiluminescent enzyme immunoassay, and changes in the percentage of PRL-positive cells in the pituitary gland were examined using an immunohistochemical method. Furthermore, an inverted culture method was used as an in vitro model of the blood-CSF barrier using epithelial cells of the human choroid plexus (HIBCPP cell line) and SDR-P-1D5 or MSH-P3 (PRL-secreting cell line derived from miniature swine hypophysis) under normoxic or hypoxic (5% oxygen) conditions, and as an index of cell activity, we used Vascular Endothelial Growth Factor (VEGF).Results and discussionSerum PRL levels were not significantly different between hypoxia/ischemia cases and other causes of death. However, PRL levels in CSF were three times higher in cases of hypoxia/ischemia than in those of the other causes of death. In the cultured cell under the hypoxia condition, PRL and VEGF showed a high concentration at 10 min. We established a brain-CSF barrier model to clarify the mechanism of PRL transport to CSF from blood, the PRL concentrations from blood to CSF increased under hypoxic conditions from 5 min. These results suggested that PRL moves in CSF through choroidal epithelium from blood within a short time. PRL is hypothesized to protect the hypoxic/ischemic brain, and this may be because of the increased transportation of the choroid plexus epithelial cells.

Prozone-like phenomenon found in chemiluminescent enzyme immunoassay using magnetic particles for measurement of serum anti-single stranded DNA antibody titers: Definition and management

BackgroundSerum anti-single stranded DNA antibody (anti-ssDNAab) is used as a marker for systemic lupus erythematosus. We found a ‘prozone-like phenomenon,’ which was different from an original prozone phenomenon, in chemiluminescent enzyme immunoassay using magnetic particles for the measurement of serum anti-ssDNAab titers. We investigated mechanisms of the prozone-like phenomenon and countermeasures to prevent it from being overlooked. MethodsThis study examined 679 samples from patients tested for anti-ssDNAab titer at our hospital. In addition, the BF photometry OD value 2 (OD2), an index of optical density, was monitored simultaneously. ResultsThe undiluted samples with a prozone-like phenomenon showed extremely lower OD2. Those samples were able to be distinguished from other samples by setting OD2 criteria based on the 95% prediction interval. Significant differences (p < 0.05) were found in the titer ratios (ten-fold diluted against undiluted) between groups with >1.5 and other groups with <1.5 for the ratios of OD2. ConclusionsWe proposed two valuable methods to find a prozone-like phenomenon: one by setting OD2 criteria based on the 95% prediction interval and the other by analyzing the ratios both in titers and OD2 between undiluted and 10-fold diluted samples.

Performance of protein induced by vitamin K absence or antagonist-II assessed by chemiluminescence enzyme immunoassay for hepatocellular carcinoma detection: a meta-analysis

Objectives: In the setting of surveillance for hepatocellular carcinoma (HCC) detection, the use of serum biomarkers in addition to ultrasonography (US) is still a matter of debate. Hence, we performed a meta-analysis to evaluate the diagnostic accuracy of protein induced by vitamin K absence or antagonist-II (PIVKA-II) and alpha-fetoprotein (AFP) alone or in combination for HCC detection in patients at risk of tumor development.Materials and methods: We performed a systematic search in PubMed and Scopus database for original articles published in English from 2011 to 2017, investigating the accuracy of PIVKA-II alone or in combination with AFP (reported as area under the curve [AUC]) for HCC detection among patients at risk of tumor development. Furthermore, we focused on studies in which serum PIVKA-II was assessed by highly sensitive chemiluminescence immunoassay (CLEIA).Results: A total of 11 studies (873 patients with HCC and 1244 patients with advanced liver disease/cirrhosis) were included in the meta-analysis. The weighted summary AUC (sAUC) of PIVKA-II and AFP for the discrimination between patients with HCC and those without was 0.791 (0.746–0.837) and 0.767 (0.732–0.803), respectively. The combination of PIVKA-II + AFP results in a sAUC of 0.859 (0.837–0.882). The performance for HCC detection of PIVKA-II + AFP was significantly superior to each biomarker used alone (ΔsAUC = 0.068, p = .032 and ΔsAUC = 0.092, p < .001, respectively).Conclusion: In clinical practice, the use of PIVKA-II + AFP in addition to US examination may improve the effectiveness of surveillance among patients at risk for HCC development.

Diagnostic and clinical role of serum proteinase 3 antineutrophil cytoplasmic antibodies in inflammatory bowel disease.

Proteinase 3 antineutrophil cytoplasmic antibodies (PR3-ANCAs) are well-known serological markers for granulomatosis with polyangiitis, but their role as serological markers for inflammatory bowel disease remains uncertain. The present study aimed to evaluate the diagnostic and clinical role of PR3-ANCAs as markers for inflammatory bowel disease. Using a new methodology with chemiluminescence enzyme immunoassay, serum PR3-ANCA titers were assessed in 102 patients with ulcerative colitis (UC), 67 patients with Crohn's disease (CD), 44 controls with other intestinal diseases, and 66 healthy controls. Associations with clinical data were investigated. The diagnostic role of PR3-ANCAs was evaluated by receiver operating characteristic analysis. Proteinase 3 antineutrophil cytoplasmic antibody titers were significantly higher in patients with UC than in those with CD patients, patients with intestinal diseases (intestinal controls), and healthy controls (all P<0.001). Receiver operating characteristic analysis demonstrated an area under the curve of 0.85 (95% confidence interval: 0.83-0.87) and showed that the manufacturer's cutoff value (3.5U/mL) had a sensitivity of 39.2% and specificity of 96.6% for UC. There was a significant difference between PR3-ANCA-positive and PR3-ANCA-negative patients with regard to disease duration (P<0.05) and disease severity (P<0.01). Proteinase 3 antineutrophil cytoplasmic antibodies were significantly more prevalent in patients with UC than in those with CD and controls. Our results suggested the role of PR3-ANCAs as serological markers for aiding in diagnosing UC and evaluating disease severity. Further prospective studies are needed across multiple populations of patients and ethnic groups.

Design and preparation of bi-functionalized short-chain modified zwitterionic nanoparticles

An ideal nanomaterial for use in the bio-medical field should have a distinctive surface capable of effectively preventing nonspecific protein adsorption and identifying target bio-molecules. Recently, the short-chain zwitterion strategy has been suggested as a simple and novel approach to create outstanding anti-fouling surfaces. In this paper, the carboxyl end group of short-chain zwitterion-coated silica nanoparticles (SiO2-ZWS) was found to be difficult to functionalize via a conventional EDC/NHS strategy due to its rapid hydrolysis side-reactions. Hence, a series of bi-functionalized silica nanoparticles (SiO2-ZWS/COOH) were designed and prepared by controlling the molar ratio of 3-aminopropyltriethoxysilane (APTES) to short-chain zwitterionic organosiloxane (ZWS) in order to achieve above goal. The synthesized SiO2-ZWS/COOH had similar excellent anti-fouling properties compared with SiO2-ZWS, even in 50% fetal bovine serum characterized by DLS and turbidimetric titration. Subsequently, SiO2-ZWS/COOH5/1 was chosen as a representative and then demonstrated higher detection signal intensity and more superior signal-to-noise ratios compare with the pure SiO2-COOH when they were used as a bio-carrier for chemiluminescence enzyme immunoassay (CLEIA). These unique bi-functionalized silica nanoparticles have many potential applications in the diagnostic and therapeutic fields. Statement of significanceReducing nonspecific protein adsorption and enhancing the immobilized efficiency of specific bio-probes are two of the most important issues for bio-carriers, particularly for a nanoparticle based bio-carrier. Herein, we designed and prepared a bi-functional nanoparticle with anti-fouling property and bio conjugation capacity for further bioassay by improving the short-chain zwitterionic modification strategy we have proposed previously. The heterogeneous surface of this nanoparticle showed effective anti-fouling properties both in model protein solutions and fetal bovine serum (FBS). The modified nanoparticles can also be successfully functionalized with a specific antibody for CLEIA assay with a prominent bio-detection performance even in 50% FBS. In this paper, we also investigated an unexpectedly fast hydrolysis behavior of NHS-activated carboxylic groups within the pure short-chain zwitterionic molecule that led to no protein binding in the short-chain zwitterion modified nanoparticle. Our findings pave a new way for the designing of high performance bio-carriers, demonstrating their strong potential as a robust platform for diagnosis and therapy.

Detection of urinary survivin using a magnetic particles-based chemiluminescence immunoassay for the preliminary diagnosis of bladder cancer and renal cell carcinoma combined with LAPTM4B.

The aim of the present study was to establish a simple step magnetic particles (MPs) based chemiluminescence enzyme immunoassay (CLEIA) for the detection of urinary survivin, and to investigate the diagnostic value of urinary survivin and lysosome-associated protein transmembrane-4β (LAPTM4B) in bladder cancer (BC) and renal cell carcinoma (RCC). The MPs-based CLEIA was developed on the basis of a double antibodies sandwich immunoreaction and luminol-H2O2 chemiluminescence system. The parameters of the method were optimized and evaluated. Urine samples were obtained from 200 BC patients, 81 RCC patients and 114 healthy individuals, and the MPs-based CLEIA method was employed to detect their urinary survivin. At the same time, the urinary LAPTM4B levels of the BC patients, RCC patients and the healthy controls were measured. The diagnostic efficiency of urinary survivin and LAPTM4B in BC and RCC was evaluated separately and jointly. A one-step MPs-based CLEIA for the detection of urinary survivin with good accuracy and precision was established. The signals were dependent on survivin concentrations in the range, 0 to 200 ng/ml, and the detection limit was 0.949 ng/ml. The areas under the receiver operating characteristic curves (AUC) were 0.771 in BC and 0.763 in RCC for urinary survivin. Urinary survivin was correlated with the tumor stage (P=0.002), lymph node metastasis (P=0.017), distant metastasis (P=0.005) and tumor size (P=0.02) of BC; however, no association with the clinicopathological parameters in RCC was observed. The AUCs for urinary LAPTM4B were 0.738 in BC and 0.704 in RCC, respectively. The AUCs for them combined were 0.842 in BC and 0.920 in RCC. The MPs-based CLEIA was performed well in the detection of urinary survivin. Urinary survivin and LAPTM4B could serve as potential biomarkers for the preliminary diagnosis of BC and RCC, and in combination they a achieved a greater diagnostic performance.

Ratio of pro-B-type natriuretic peptide (BNP) to total BNP is decreased in mild, but not severe, acute decompensated heart failure patients: A novel compensatory mechanism for acute heart failure

BackgroundA recent study showed that both glycosylation of pro-B-type natriuretic peptide (BNP) and the proBNP/total BNP ratio are decreased in acute decompensated heart failure (ADHF). However, the following points regarding the proBNP/total BNP ratio have not been determined in patients with ADHF: 1) the relationship with the severity of ADHF, 2) the changes in the ratio during treatment, and 3) the relationship with cyclic guanosine monophosphate (cGMP)-generating activity. MethodsPlasma proBNP and total BNP (proBNP+mature BNP) were measured in patients with ADHF (n=154). Measurement was performed on admission, 3 and 7days after admission, and before discharge using recently developed sandwich chemiluminescence enzyme immunoassays. The percent proBNP was calculated as: (proBNP/total BNP)×100. ResultsOn admission, %proBNP was higher in patients with severe ADHF than in patients with mild ADHF (median: 61.7% vs. 56.2%, respectively; p<0.01), while the plasma cGMP/total BNP ratio, an index of the biological activity of BNP, was lower (p<0.001). In patients with severe ADHF, the higher %proBNP and lower cGMP/total BNP ratio were unchanged during hospitalization, whereas %proBNP increased gradually in patients with mild ADHF and the cGMP/total BNP ratio also increased at 3days after admission. ConclusionThese findings suggest that in patients with mild ADHF, compensation for heart failure occurs via increased proBNP processing, leading to increase of mature BNP and activation of the BNP/cGMP cascade. In contrast, this compensatory mechanism may be impaired in patients with severe ADHF and a vicious cycle can potentially occur.

An ultrasensitive chemiluminescence immunoassay for fumonisin B1 detection in cereals based on gold-coated magnetic nanoparticles.

In the present study, a novel highly sensitive magnetic enzyme chemiluminescence immunoassay (MECLIA) was developed to detect fumonisin B1 (FB1 ) in cereal samples. The gold-coated magnetic nanoparticles (Fe3 O4 @Au, GoldMag) were used as solid phase carrier to develop a competitive CLIA for detecting FB1 , in which FB1 in samples would compete with FB1 -ovalbumin coated on the surface of Fe3 O4 @Au nanoparticles for binding with FB1 antibodies. Successively, horseradish peroxidase labeled goat anti-rabbit IgG (HRP-IgG) was conjugated with FB1 antibodies on the microplate. In substrate solution containing luminol and H2 O2 , HRP-IgG catalyzed luminol oxidation by H2 O2 , generating a high chemiluminescence signal. The FB1 immune GoldMag particles were characterized by Fourier transform infrared spectroscopy, scanning electron microscope and zeta potential analysis, etc. RESULTS: The concentrations and the reaction times of these immunoreagents were optimized to improve the performances of this method. The established method could detect as low as 0.027 ng mL-1 FB1 from 0.05 ng mL-1 to 25 ng mL-1 , demonstrating little cross-reaction (less than 2.4%) with other structurally related compounds. The average intrassay relative SD (RSD) (n = 6) was 3.4% and the average interassay RSD (n = 6) was 5.4%. This method was successfully applied for the determination of FB1 in corn and wheat and gave recoveries of between 98-110% and 91-105%, respectively. The results of the present study suggest that the MECLIA approach has potential application for high-throughput fumonisin screening in cereals. © 2018 Society of Chemical Industry.

Elevated serum Krebs von den Lungen-6 in systemic sclerosis: a marker of lung fibrosis and severity of the disease.

We aimed to assess the clinical significance of Krebs von den Lungen-6 (KL-6) in the diagnosis and severity of interstitial lung disease (ILD) in a French cohort of patients with systemic sclerosis (SSc). Serum KL-6 concentrations were measured with chemiluminescent enzyme immunoassay (CLEIA) in 75 SSc patients. Patients were divided into two groups according to the presence of interstitial lung disease (SSc-ILD versus SSc-without ILD) on chest High-Resolution Computed Tomography. Pulmonary function tests, main manifestations and severity of the lung disease (Medsger's severity scale) were collected. KL-6 serum concentrations were significantly higher in SSc-ILD patients than in those without ILD (p < 10-4) and were inversely correlated with forced vital capacity, total lung capacity and diffuse lung capacity of carbon monoxide. Serum KL-6 level superior to 872U/ml appeared as the optimal cut-off value associated with ILD. Patients with a restrictive pulmonary syndrome and dyspnoea had significant higher KL-6 serum concentrations. SSc patients with anti-topoisomerase 1 antibodies had higher KL-6 serum levels than patients with anti-centromere antibodies (p < 10- 4). ILD and anti-topoisomerase 1 antibodies were independent factors associated with KL-6 in multivariate analysis. Interestingly, KL-6 serum concentrations positively increased with the patient lung severity. Our study confirms that KL-6 is an accurate biomarker for the diagnosis of SSc-ILD in a French cohort of patients. High KL-6 levels should prompt physicians to assess ILD with pulmonary imaging and pulmonary functions tests. Prospective clinical studies are still required to determine whether levels of KL-6 might predict progression of ILD as well as its usefulness in the timing of therapeutic intervention.

Association of CA 15-3 and CEA with Clinicopathological Parameters In Patients With Metastatic Breast Cancer

Background. Breast cancer is the most common cancer and the leading cause of cancer death for women, a third of women are diagnosed with breast cancer at a late stage when the disease has a poor prognosis. Serum tumor markers have been widely used as noninvasive tools for measuring treatment response, early diagnosis of recurrence and predicting prognosis. In breast cancer, the most widely used serum tumor markers are cancer antigen 15-3 (CA 15-3) and carcinoembryonic antigen (CEA). The aim of this study was to investigate the association of serum CA15-3 and CEA levels with clinicopathological parameters in patients diagnosed with metastatic breast cancer (MBC). Patients and methods. This retrospective study was conducted on 50 patients who had used to predict response to chemotherapy in patients with metastatic breast cancer. The concentration of serum CA15-3 and CEA levels were measured using chemiluminescent enzyme immunoassays (ABBOTT ARCHITECT). The upper limits of normal for CA15-3 and CEA were 31.3 U/ml and 5 ng/ml, respectively. Result. Of the 50 patients, elevated CA 15-3 and CEA levels at initial diagnosis of recurrence were identified in 37 (74%) and 32 (64%) patients, respectively. Elevated CA 15-3 and CEA levels were significantly associated with breast cancer molecular subtypes (P=0.005 and P=0.008, respectively). Elevated CA 15-3 level was correlated with bone metastasis (P=0.047). Conclusion. CA 15-3 and CEA level elevation at initial diagnosis of recurrence were found to be associated with breast cancer molecular subtype; these serum tumor markers are frequently increased in the HER2-enriched and triple negative (TN) molecular subtypes of breast cancer.

Development of a chemiluminescent enzyme immunoassay to detect cadmium in cereal samples

ABSTRACT In this study, we develop a sensitive indirect competitive chemiluminescent enzyme immunoassay (ic-CLEIA) to detect cadmium (Cd) in cereals. A luminol-hydrogen peroxide chemiluminescence system catalysed by horseradish peroxidase (HRP) was used as the signal detecting system. The method showed a half-maximal inhibition concentration (IC50) of 0.5 ng/mL and a limit of determination (LOD) of 0.06 ng/mL. The assay indicated an effective linear range from 0.16 to 1.56 ng/mL. There were no obvious cross-reactivities with other metal ions, including Hg2+, Pb2+, As2+, Ag+, Fe3+, Cu2+, Cr2+, Au3+, Ca2+, Mg2+, Mn2+ and Zn2+. Recovery rates ranged from 79.2% to 120.0% for rice, maize, wheat, brown rice and glutinous rice samples. Twenty-five practical cereal samples were analysed, and the comparative analysis of the results showed a strong correlation (r = 0.984) between the CLEIA and the GFAAS methods. The results indicated that the ic-CLEIA developed was acceptable to screen for cadmium in cereal samples.