Electrochemiluminescence Immunoassay Research Articles

The role of toxoplasma, rubella, cytomegalo virus, herpes virus infection as a risk factor for sensory hearing loss in children

Toxoplasma, rubella, cytomegalovirus and herpes virus infection (TORCH) are syndromes that are considered risk factors for deafness.. This study aims to prove the risk factors which play the most significant role in the incidence of Sensory Hearing Loss in children. This used a case-control design, conducted at JIH Yogyakarta Hospital started from December 2023 to June 2024. All participants aged less than 5 years underwent oto-acoustic emission (OAE) examination, then determined presence or absence toxoplasma, rubella, cytomegalovirus and herpes virus using the electrochemiluminescence immunoassay (ECLIA) method. The inclusion criteria for the case group were: 1) patients diagnosed with sensory hearing loss (SHL), while the control group was normal. The exclusion criteria for the case and control groups there were non-infectious risk factors. Based on a type I error of 5% and type II error of 20%. The recommended sample size is 18 samples per group. Statistical analysis used stratified statistical analysis. The results of this study show that the combination of rubella + CMV had the greatest odds ratio (OR: 8) of sensory hearing loss, CMV OR: 0.62, herpes simplex virus OR: 0.28, combination of rubella + herpes simplex virus OR: 0.28, toxoplasma + CMV OR: 0.28, rubella obtained OR: 1 .5, and the combination of rubella + CMV + herpes simplex virus OR: 0.1. Based on these results the combination of rubella + CMV had the greatest OR compared to the combination of other risk factors and single risk factor.

The fabrication of phosphotungstate@UIO-Au/reduced graphene oxidation for electrochemical ultrasensitive detection of alpha-fetoprotein.

As an early multi-purpose tumor marker of hepatocellular carcinoma, alpha-fetoprotein (AFP) plays a vital role in early diagnosis and treatment. To achieve the early and accurate determination of AFP, the POMOF was fabricated by embedding H3PW12O40 (PW12) into UIO-66-NH2, further immobilized on reduced GO (rGO) and fabricated an innovative POMOF nanocomposite (PW@UIO-Au/rGO) as an electrochemical immunosensor (ECI-sensor). The PW@UIO-Au/rGO achieved 17-fold signal enhancement owing to their synergistic effect, enabling PW@UIO-Au/rGO exhibit high oxidase-like catalytic activity, facilitating their sensing performance. Under optimal experimental conditions, the proposed PW@UIO-Au/rGO ECI-sensor presented excellent sensing performance over a wide range from 0.01 ng mL-1 to 500 ng mL-1 with ultra-low detection of 4.0 pg mL-1. Notably, sensing results in real serum samples were verified by the clinical enzyme-linked immunosorbent assay (ELISA) and electrochemiluminescence immunoassay (ECL) methods with excellent accuracy and consistency, indicating the excellent environmental tolerance of the proposed ECI-sensor. This work provided a promising strategy for designing feasible ultra-sensitive probe for sensing AFP in clinical test.

Development of a Sensitive and Reliable Meso Scale Discovery-Based Electrochemiluminescence Immunoassay to Quantify TDP-43 in Human Biofluids

Development of a Sensitive and Reliable Meso Scale Discovery-Based Electrochemiluminescence Immunoassay to Quantify TDP-43 in Human Biofluids

The role of vitamin D metabolism in regulating bone turnover in adolescents with perinatally-acquired HIV in southern Africa: a cross-sectional study in Zimbabwe and Zambia.

Vitamin D dysregulation can occur in people living with HIV, disrupting calcium homeostasis and bone turnover. We aimed to investigate the potential mechanisms by which vitamin D regulates bone turnover in adolescents living with perinatally-acquired HIV (ALWH) in southern Africa. A pre-planned secondary analysis was performed of baseline data from the VITALITY trial [PACTR20200989766029] which enrolled ALWH (11-19years) taking antiretroviral therapy for ≥6months, and recorded socio-demographic, clinical and dietary data. After over-night fasting, vitamin D metabolites [25(OH)D, 1,25(OH)2D, 24,25(OH)2D], intact parathyroid hormone (PTH) and bone turnover markers (BTMs) [CTX and P1NP] were measured. Tandem Mass Spectrometry measured vitamin D metabolites, whilst intact PTH and BTMs were analysed by electrochemiluminescence immunoassay. Stratified by 25(OH)D [<75 vs ≥75nmol/L], associations between standardized concentrations (β = standard deviations) of vitamin D metabolites, intact PTH and BTMs were assessed using structural equations modelling (SEM) adjusted for age, sex and country (Zimbabwe/Zambia). Among the 842 ALWH enrolled, the median dietary calcium intake was 100mg [IQR:55-145]. The SEM showed PTH was positively associated [β 0.21, 95%CI: 0.1,0.32] with 1,25(OH)2D, only when 25(OH)D was <75nmol/L vs ≥75nmol/L [β 0.23, 95%CI: -0.13,0.59], with evidence of an interaction [β -0.11, 95%CI: -0.20,-0.02]. A positive relationship between 25(OH)D and 24,25(OH)2D was seen irrespective of 25(OH)D concentration. 24,25(OH)2D was inversely related to BTMs, particularly when 25(OH)D was <75nmol/L [CTX: β -0.15, 95%CI: -0.24,-0.06, and P1NP: β -0.14, 95%CI: -0.22,-0.06]. There was interaction between dietary calcium and 25(OH)D on PTH [β -0.15, 95% CI: -0.22,-0.07] suggesting an interaction between low 25(OH)D and low dietary calcium which increases PTH. In conclusion, associations between 25(OH)D, PTH, 1,25(OH)2D and BTMs in ALWH appear dependent upon 25(OH)D concentrations <75nmol/L and calcium intake. A novel, potentially causal pathway between 25(OH)D, 24,25(OH)2D and BTMs was seen. Findings enhance understanding of vitamin D metabolism in people living with HIV.

Association of serum vitamin C concentrations with Alzheimer’s disease mortality among U.S. adults

ABSTRACT Background The association between vitamin C status and Alzheimer’s disease (AD) mortality remains unclear. Methods A total of 4864 adults aged 60 years or above from the National Health and Nutrition Examination Survey III 1988–1994 were included in this study. Serum vitamin C levels were measured by the fully automated electrochemiluminescence immunoassay. Death and underlying causes of death were ascertained by linkage to death records through December 31, 2019. Cox proportional hazards regression models were used to evaluate the association between serum vitamin C and AD mortality. Results During 65,251 person-years of follow-up (a median follow-up of 12.0 years), 158 deaths occurred from AD. After adjustment for age, sex, race/ethnicity, socioeconomic status, lifestyle and dietary factors, body mass index, baseline diseases and vitamin C supplement use, compared with participants with deficiency serum vitamin C concentrations (< 53 µmol/L), the multivariate-adjusted HR (95% CI) for AD mortality was 0.62 (0.39-0.99) for participants with adequate serum vitamin C concentrations (53-70 µmol/L) and 0.64 (0.34-1.18) for participants with saturate serum vitamin C concentrations (> 70 µmol/L). Conclusion In this nationally representative sample of US adults, higher serum vitamin C was significantly associated with lower risk of AD mortality. These findings suggest that maintaining adequate vitamin C status may aid in lowering AD mortality risk.

A fluorescence-based lateral flow immunoassay using AIEgen-encapsulated nanoparticles to rapidly and sensitively detect pro-gastrin-releasing peptide.

Afluorescence lateral flow immunoassay (F-LFIA) is presentedusing nanoparticles with encapsulated molecules whose emission is caused by aggregation as the fluorescent label to quantitatively detect gastrin-releasing peptide precursor(proGRP) in serum. The detection system was optimized to achieve a broad linear detection range of 10 ~ 5000 pg/mL and a detection limit of 6 pg/mL for F-LFIA. The proposed method exhibited good sensitivity, specificity, and reproducibility. The performance and applicability of the F-LFIA were evaluated in the analysisof 183 human serum samples, and the results were strongly correlated with those of the electrochemiluminescence immunoassay. The proposed F-LFIA can serve as a precise and rapid detection method to detect proGRP and has potential for the early diagnosis of small-cell lung cancer (SCLC).

Prolactin Role in COVID-19 and Its Association with the Underlying Inflammatory Response.

The COVID-19 pandemic has prompted interest in identifying reliable biomarkers to predict disease severity and guide clinical decisions. Prolactin (PRL), a hormone traditionally associated with lactation, has gained attention for its role in immune modulation. This study aimed to assess PRL as a biomarker for disease severity in COVID-19. A prospective cohort of 142 patients with moderate to severe COVID-19, defined as a WHO-CPS 5 or 6, was recruited from the University General Hospital of Patras. Baseline PRL levels were measured using an electrochemiluminescence immunoassay, and serum cytokines, including IL-1β, IL-6, IL-8, IL-10, IL-12p70, and TNF-α, were quantified through flow cytometry. Clinical outcomes, including mortality and the need for invasive mechanical ventilation (IMV), were recorded. Results indicated that PRL levels were significantly higher in female patients (12.95 ng/mL vs. 9.40 ng/mL, p < 0.001) but they did not correlate with key severity indices such as CCI, SOFA score upon admission or inflammatory markers. No significant associations between baseline PRL levels, cytokine concentrations, and clinical outcomes in COVID-19 were noted. Our findings suggest that PRL may lack prognostic reliability for disease severity compared to more established predictive markers and that its role in the immune response remains uncertain.

Urine lipoarabinomannan concentrations among HIV-negative adults with pulmonary or extrapulmonary tuberculosis disease in Vietnam.

Lipoarabinomannan (LAM) is a promising target biomarker for diagnosing subclinical and clinical tuberculosis (TB). Urine LAM (uLAM) testing using rapid diagnostic tests (RDTs) has been approved for people living with HIV (PLWH), however there is limited data regarding uLAM levels in HIV-negative (HIV-ve) adults with clinical TB. We conducted a clinical study of adults presenting with clinical TB-related symptoms at the National Lung Hospital in Hanoi, Vietnam. The uLAM concentrations were measured using electrochemiluminescent (ECL) immunoassays and compared to a microbiological reference standard (MRS) using GeneXpert Ultra and TB culture testing. Estimated uLAM concentrations above plate specific calculated limit of detection (LOD) were considered uLAM positive. Additional microbiological testing was conducted for possible extrapulmonary TB (EPTB). Among 745 participants enrolled, 335 (44.9%) participants with presumptive pulmonary TB (PTB) and 6 (11.3%) participants with presumptive EPTB had confirmed TB disease. Overall, the S/A antibody pair had a sensitivity of 39% (95% Confidence Interval [CI] 0.33, 0.44) and a specificity of 97% (95% CI 0.96, 0.99) compared to the MRS. The F/A antibody pair had a sensitivity of 41% (95% CI 0.35, 0.47) and a specificity of 79% (95% CI 0.75, 0.84). S/A provided greater discriminatory ability compared to F/A for both individuals with presumptive PTB (AUROC: 0.74 vs 0.63, p<0.0001) and presumptive EPTB (0.76 vs 0.54, p = 0.045) when using the MRS. Among HIV-ve participants in an adult cohort in Vietnam, the concentrations of uLAM remained relatively low for people with clinical TB, which may present challenges for improving RDT sensitivity.

Noninvasive, Multimodal Inflammatory Biomarker Discovery for Systemic Inflammation (NOVA Study): Protocol for a Cross-Sectional Study.

Prolonged systemic inflammation is recognized as a major contributor to the development of various chronic inflammatory diseases. Daily measurements of inflammatory biomarkers can significantly improve disease monitoring of systemic inflammation, thus contributing to reducing the burden on patients and the health care system. There exists, however, no scalable, cost-efficient, and noninvasive biomarker for remote assessment of systemic inflammation. To this end, we propose a novel, multimodal, and noninvasive approach for measuring inflammatory biomarkers. This study aimed to evaluate the relationship between the levels of inflammatory biomarkers in serum (gold standard) and those measured noninvasively in urine, sweat, saliva, exhaled breath, stool, and core body temperature in patients with systemic inflammation. This study is a single-center, cross-sectional study and includes a total of 20 participants (10 patients with systemic inflammation and 10 control patients). Eligible participants provide serum, urine, sweat, saliva, exhaled breath, and stool samples for biomarker analyses. Core body temperature is measured using a sensor. The primary end point is the level of C-reactive protein (CRP). The secondary end points are interleukin (IL)-1β, IL-6, IL-8, IL-10, and tumor necrosis factor-α levels. The tertiary end points are fractional exhaled nitric oxide, calprotectin, and core body temperature. Samples will be collected in 2 batches, enabling preliminary analysis of the first batch (patients 1-5 from each group). The full analysis will include both batches. CRP and cytokine levels will be measured using enzyme-linked immunosorbent assay and electrochemiluminescence immunoassay. For statistical analysis, the Shapiro-Wilk test will be used to evaluate the normality of the distribution in each variable. We will perform the 2-tailed t test or Wilcoxon rank sum test to compare the levels of inflammatory biomarkers between patients with systemic inflammations and control patients. Pearson and Spearman correlation coefficients will assess the relationship between inflammatory biomarkers from noninvasive methods and serum biomarkers. Using all-subset regression analysis, we will determine the combination of noninvasive methods yielding the highest predictive accuracy for serum CRP levels. Participants' preferences for sampling methods will be assessed through a questionnaire. The study received ethics approval from the independent research ethics committee of Canton Zurich on October 28, 2022. A total of 20 participants participated in the study measurements. Data collection started on February 22, 2023, and was completed on September 22, 2023. Participants were on average 52.8 (SD 14.4; range 24-82) years of age, and 70% (14/20) of them were women. The analysis results reporting findings are expected to be published in 2025. This study aims to evaluate the feasibility of noninvasive, multimodal assessment of inflammatory biomarkers in patients with systemic inflammation. Promising results could lead to the creation of noninvasive and potentially digital biomarkers for systemic inflammation, enabling continuous monitoring and early diagnosis of inflammatory activity in a remote setting. DERR1-10.2196/62877.

Investigation of 25-hydroxy vitamin D deficiency in healthy adults aged 18-65 years in Istanbul, Türkiye

Background :To determine the prevalence of 25-hydroxy vitamin D (25(OH)D) deficiency in healthy adult patients who presented to our hospital in Istanbul province and to present the difference between vitamin 25(OH)D levels by gender, age group, season, and month. Materials and Methods: The vitamin 25(OH)D levels of 9,778 adults who presented to the internal medicine checkup outpatient clinic of our hospital between January 2022 and December 2023 were analyzed retrospectively. Individuals with chronic disorders were excluded from the study. The adult patients included in the study were divided into two groups by age (18-50 and 51-65 years). Serum 25(OH)D levels were measured using the electrochemiluminescence immunoassay method. A serum 25(OH)D level was regarded as deficient if below 20 ng/mL, insufficient if 20-30 ng/mL, and sufficient if above 30 ng/mL. The 25(OH)D levels of the patients were investigated by age, gender, season, and month. Results: After measurement, vitamin D levels were deficient in 57.2% of the patients (n=5,592), insufficient in 28.2% (n=2,756), and sufficient in 14.6% (n=1,430). The mean vitamin D level of the 18-50 age group was significantly lower than that of the group 51-65 age group (p=0.001; p&lt;0.01). The vitamin D levels did not statistically significantly differ by gender (p=0.085, p&gt;0.05). The mean vitamin D levels were 17.99±10.88 ng/mL in winter, 18.11±12.69 ng/mL in spring, 22.08±11.58 ng/mL in summer, and 21.67±10.82 ng/mL in fall. There were statistically significant differences according to the season and month of hospital presentation (p=0.001; p&lt;0.01). Conclusion: The prevalence of vitamin D deficiency (below 20 ng/mL) in healthy adults aged 18-65 years in Istanbul was 57.2%. This prevalence varied across seasons and months, indicating that sunlight is not being used sufficiently. Vitamin D deficiency in Istanbul presents a major problem that needs to be remedied.

Complement proteins and complement regulatory proteins are associated with age-related macular degeneration stage and treatment response

BackgroundDysregulation of the complement system is involved in development of age-related macular degeneration (AMD). The complement cascade is regulated by membrane bound complement regulatory proteins (Cregs) on mononuclear leukocytes among others. This study aims to investigate systemic complement proteins and Cregs in AMD stages and their association with treatment response in neovascular AMD (nAMD).MethodsIn this clinical prospective study, treatment-naïve patients with nAMD, intermediate AMD (iAMD) and healthy controls were recruited and systemic complement proteins C3, C3a and C5a were investigated with electrochemiluminescence immunoassays, and Creg expression (CD35, CD46 and CD59) on T cells (CD4 + and CD8+) and monocytes (classical, intermediate and non-classical) investigated with flow cytometry. Treatment response in nAMD patients was evaluated after loading dose and after one year, and categorized as good, partial or poor. Complement proteins and Creg expression levels were compared between healthy controls, iAMD and nAMD, as well as between good, partial and poor nAMD treatment response groups. Polymorphisms in the CFH and ARMS2 genes were analyzed and compared to complement proteins and Creg expression levels in nAMD patients.ResultsOne hundred patients with nAMD, 34 patients with iAMD and 61 healthy controls were included. 94 nAMD patients completed the 1-year follow-up. Distribution of treatment response in nAMD was 61 (65%) good, 26 (28%) partial, and 7 (7%) poor responders. The distribution of 1-year treatment response was 50 (53%) good, 33 (36%) partial, and 11 (11%) poor responders. The concentrations of systemic C3, C3a, and the C3a/C3-ratio were significantly increased in patients with nAMD compared to healthy controls (P < 0.001, P = 0.002, and P = 0.035, respectively). Systemic C3 was also increased in iAMD compared to healthy controls (P = 0.031). The proportion of CD46 + CD4 + T cells and CD59 + intermediate monocytes were significantly decreased in patients with nAMD compared to healthy controls (P = 0.018 and P = 0.042, respectively). The post-loading dose partial treatment response group had significantly lower concentrations of C3a and C5a compared to the good response group (P = 0.005 and P = 0.042, respectively). The proportion of CD35 + monocytes was significantly lower in the 1-year partial response group compared to the 1-year good response group (P = 0.039). High-risk CFH genotypes in nAMD patients was associated with increased C3a, C3a/C3-ratio, and expression levels of CD35 + CD8 + T cells and CD46 + classical monocytes, while expression level of CD46 + non-classical monocytes was decreased.ConclusionElevated concentrations of systemic complement proteins were found in patients with iAMD and nAMD. Decreased Creg expression levels were found in patients with nAMD. Partially responding nAMD patients had a dysregulated complement system and Cregs compared to good responders.

Photoinduced Electrochemiluminescence Immunoassays.

Optimization of electrochemiluminescence (ECL) immunoassays is highly beneficial for enhancing clinical diagnostics. A major challenge is the improvement of the operation conditions required for the bead-based immunoassays using the typical [Ru(bpy)3]2+/tri-n-propylamine (TPrA) system. In this study, we report a heterogeneous immunoassay based on near-infrared photoinduced ECL, which facilitates the imaging and quantitative analysis of [Ru(bpy)3]2+-modified immunobeads at low anodic potential. The photovoltage generated by the photoanode under near-infrared light promotes oxidation processes at the electrode/electrolyte interface, thus considerably lowering the onset potential for both TPrA oxidation and ECL emission. The anti-Stokes shift between the excitation light (invisible to the human eyes) and the visible emitted light results in a clear and stable signal from the immunobeads. In addition, it offers the possibility of site-selective photoexcitation of the ECL process. This approach not only meets the performance of traditional ECL immunoassays in accuracy but also offers the additional benefits of lower potential requirements and enhanced stability, providing a new perspective for the optimization of commercial immunoassays.

Prevalence and risk factors for blood-borne viruses among multi-transfused patients in Sana'a City, Yemen

Background: Blood-borne viruses (BBVs), like hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) among multi-transfused patients (MTPs), remain a major public health problem in Yemen. This study aimed to determine the seroprevalence of BBVs and associated risk factors among MTPs. Methods: A cross-sectional study was conducted on MTPs at the Yemeni Society for Thalassemia, National Oncology Center, and Al Kuwait University Hospital in Sana’a City. Data were collected through face-to-face interviews using a predesigned questionnaire. Blood samples were drawn and tested for HBsAg, anti-HCV, and HIV-1,2 by using an electrochemiluminescence immunoassay technique. Results: Among 361 MTPs, the overall seroprevalence of BBVs was 6.8%; seropositivity of HBsAg, anti-HCV, and anti-HIV-1,2 was 3.9%, 2.9%, and 0.0%, respectively. An increase in family size and low income were significantly associated factors with HBV infection. In addition, increases in age and blood transfusion units were found to be significant predictors for HCV (p&lt;0.05). Conclusion: Although the seroprevalence of BBVs is low, it remains a major problem among MTPs. The most frequent infection was HBV, followed by HCV, with a significantly higher rate among leukemia patients. Regular mentoring for viral markers and mandatory implementation of HCV antigen-antibodies testing as well as advanced technology in blood screening are highly recommended.

N-terminal prohormone of brain natriuretic peptide predicts recurrent cardiovascular events in patients with acute coronary syndrome both in the acute and post-discharge setting: a TRACER substudy

Abstract Background N-terminal prohormone of brain natriuretic peptide (NT-proBNP) is a circulating peptide released by the heart in response to increased wall tension and stretching, for example, occurring during myocardial and/or atrial dysfunction. NT-proBNP is a diagnostic and prognostic marker in patients with heart failure but might also have prognostic utility in the acute phase of patients with acute coronary syndrome (ACS) and at one month after ACS. Purpose To assess the prognostic value of NT-proBNP over time in patients with ACS both in the acute setting and when re-assessed after one month. Methods The TRACER study randomized 12,944 patients with non-ST-segment elevation ACS (NSTE-ACS) to treatment with vorapaxar vs. placebo. Plasma samples for biomarker analyses were obtained at randomization (median 21 hours after hospital admission) in 6,800 patients and at an outpatient visit after one month in 5,313 patients. NT-proBNP was analysed using the Elecsys electrochemiluminescence immunoassays method. The primary composite endpoint in this substudy was the one-year risk of cardiovascular (CV) mortality, myocardial infarction, or ischaemic stroke. Associations between continuous natural log-transformed NT-proBNP levels and outcomes were assessed using Cox regression models accounting for study treatment and established risk factors. Results The median concentration of NT-proBNP during hospitalization for ACS and after one month was 496 ng/L and 264 ng/L, respectively. Higher age, female sex, a history of heart failure, and lower body mass index were independently associated with higher levels of NT-proBNP among patients in the acute setting, with renal disease also being an important factor after one month. The composite outcome of CV mortality, MI, or ischaemic stroke occurred in 901 patients (incidence rate 10.1 per 100 person-years) included at baseline and in 381 patients (incidence rate 5.4 per 100 person-years) included at one month. Higher circulating levels of NT-proBNP were independently associated with a higher risk of the composite endpoint at baseline (adjusted hazard ratio with 95% confidence interval comparing the third vs. the first sample quartile: 1.25 [1.03 – 1.51]) and at one month (1.56 [1.15 – 2.11]) (Figure 1 and 2). Incorporating NT-proBNP at baseline into a model with other established risk factors increased the concordance index of the multivariable model from 0.656 to 0.660 (p &amp;lt; 0.001), and after one month, from 0.711 to 0.733 (p &amp;lt; 0.001). These findings remained consistent across the various components of the composite endpoint. Conclusions In patients with ACS, the level of NT-proBNP is an indicator of increased risk of CV outcomes both in the acute setting and, even more pronounced, one month after the index ACS. Measuring NT-proBNP provided incremental prognostic information beyond established risk factors, both in the acute and post-discharge settings.Fig 1.NT-proBNP quartile groupsFig 2.NT-proBNP and CV outcome

Troponin T as a risk marker for recurrent cardiovascular events in the post-discharge setting one month after acute coronary syndrome: a TRACER substudy

Abstract Background Troponin T (TnT) is a protein found in cardiac myocytes that is released during myocardial injury, such as myocardial infarction (MI). TnT levels rapidly rise during an MI, remain elevated for several days, and are a key criterion for diagnosing MI. Additionally, circulating TnT levels may offer prognostic information later, particularly during the rehabilitation phase after an acute coronary syndrome (ACS). Purpose To examine the relationship between circulating TnT at one month after hospitalisation for ACS and subsequent cardiovascular (CV) events. Methods The TRACER trial randomly assigned 12,944 patients diagnosed with non-ST-segment elevation ACS (NSTE-ACS) to receive either vorapaxar or placebo. Plasma samples were obtained after one month, and high-sensitivity (hs)-TnT was measured among 5,313 patients using the Elecsys electrochemiluminescence immunoassays. In this sub-study, the primary composite endpoint was the one-year risk of CV mortality, MI, or ischaemic stroke. Associations with outcomes were evaluated using Cox regression models, both unadjusted and adjusted for clinical baseline characteristics. Results The median concentration of hs-TnT was 11 ng/L one month after hospitalisation for ACS. Higher levels of hs-TnT at one month were associated with older age, coronary artery bypass surgery during the index ACS, male sex, a history of heart failure, renal disease, and diabetes mellitus. The composite outcome of CV mortality, MI, or ischaemic stroke occurred in 381 patients (incidence rate 5.4 per 100 person-years). Hs-TnT at one month after ACS was independently associated with the risk of the composite CV endpoint (relative hazard ratio with 95% confidence interval comparing the third vs. the first sample quartile: 2.40 [1.80 – 3.20]) (see Figure 2). Similarly, hs-TnT, when added to a model including established risk factors, increased the concordance index of the multivariable model from 0.711 to 0.740 (p&amp;lt;0.001). The results were consistent across the different components of the composite endpoint. Conclusions The level of hs-TnT provides useful information on the risk of future CV events in patients when measured one month after an ACS. This information might be useful for optimising secondary preventive treatment following an ACS.Figure.Hs-TnT and composite CV outcome

Ultrasensitive ECL immunoassay for CA15-3 via self-enhanced L012-loaded ZnNi-MOF as an emitter and CeO2–Pt as a co-reaction accelerator

Improvement in the sensitivity and accuracy of ECL-based biosensors, to a great extent, depends on the fabrication of high-performance electrochemiluminescence (ECL) sensors. Herein, polyethyleneimine (PEI)-grafted bimetallic ZnNi metal-organic framework (ZnNi-MOF/PEI) nanospheres were synthesized to prepare a L012-based ECL immunosensor for detecting carbohydrate antigen 15-3 (CA15-3). The introduced PEI was utilized not only as a bridging element for L012 luminophore and detection antibody (Ab2) immobilization but also as a co-reactant for generating the self-enhanced ZnNi-MOF/PEI-L012@Ab2 ECL signal probe. Furthermore, Pt nanoparticle-functionalized CeO2 nanorods (CeO2–Pt) featuring high-efficiency electrocatalytic properties, as a co-reaction accelerator, could catalyze H2O2 to generate abundant reactive oxygen species (ROS), further augmenting the ECL signal of ZnNi-MOF/PEI-L012@Ab2. In the presence of CA15-3 antigen, the capture antibody (Ab1)-conjugated CeO2–Pt complex (CeO2–Pt@Ab1) and ZnNi-MOF/PEI-L012@Ab2 would get closer to each other, with the formation of a “signal-on” sandwich-type ECL immunosensor. The ZnNi-MOF-assisted ECL biosensor achieved a detection limit of down to 5.75✕10−5 U mL−1. This work shows distinguished potential for measuring low levels of biomarkers that may help in the clinical diagnosis of breast cancer.

Solid-phase electrochemiluminescence immunosensing platform based on bipolar nanochannel array film for sensitive detection of carbohydrate antigen 125.

Development of simple solid-phase electrochemiluminescence (ECL) immunosensor with convenient fabrication for high-performance detection of tumor biomarkers is crucial. Herein, a solid-phase ECL immunoassay was constructed based on a bipolar silica nanochannel film (bp-SNA) modified electrode for highly sensitive detection of carbohydrate antigen 125 (CA 125). Inexpensive and readily available indium tin oxide (ITO) electrode was used as the supporting electrode for the growth of bp-SNA. bp-SNA consists of a bilayer SNA film with different functional groups and charge properties, including negatively charged inner layer SNA (n-SNA) and positively charged outer layer SNA (p-SNA). The nanochannels of bp-SNA were used for the immobilization of ECL emitter tris(bipyridine)ruthenium(II), while the outer surface was utilized for constructing the immunorecognition interface. Due to the dual electrostatic interaction composed of electrostatic attraction from n-SNA and electrostatic repulsion from p-SNA, ECL emitter could be stably confined within bp-SNA, providing stable and high ECL signals to the modified electrode. After amino groups on the outer surface of bp-SNA were derivatized with aldehyde groups, recognition antibodies could be covalently immobilized, and an immunosensor was obtained after blocking nonspecific sites. When CA 125 binds to the antibodies on the recognition interface, the formed complex reduces the diffusion of the co-reactant tripropylamine (TPrA) to the supporting electrode, decreasing the ECL signal. Based on this mechanism, the constructed immunosensor can achieve sensitive ECL detection of CA 125. The linear detection range is from 0.01 to 100U/mL, with a detection limit of 4.7mU/mL. CA 125 detection in serum is also achieved. The construction immunosensor has advantages including simple and convenient fabrication, high stability of the immobilized emitter, and high selectivity, making it suitable for CA 125 detection.

Evaluation of a multiplexed immunoassay for assessing long-term humoral immunity Orthopoxviruses

BackgroundThe 2022 Monkeypox virus (MPXV) global outbreak boosted development of multiple serological assays to aid understanding of Mpox immunology. ObjectivesThe study aimed to assess a multiplexed solid-phase electrochemiluminescence immunoassay (Meso Scale Discovery (MSD)) for simultaneous detection of antibodies against MPXV, including A35, E8 and M1 antigens, along with corresponding Vaccina Virus (VACV) homologues and demonstrate its accuracy in assessing antibody titres post-vaccination and infection. MethodsAssay performance was assessed for simultaneous detection of antibodies against MPXV and corresponding VACV antigens. Sensitivity and specificity were evaluated with paediatric negatives (n = 215), pre- and post-IMVANEX vaccinated (n = 80), and MPXV (Clade IIb, n = 39) infected serum samples. ResultsThe assay demonstrated high specificity (75.68 % (CI: 69.01–81.29) - 95.98 % (CI:92.54–97.87)) and sensitivity (62.11 % (CI:52.06–71.21) - 98.59 % (CI:92.44 %–99.93 %)) depending on the Orthopoxvirus antigen. Preferential binding was observed between MPXV-infected individuals and MPXV antigens, while vaccinated individuals exhibited increased binding to VACV antigens. These results highlight differential binding patterns between antigen homologues in related viruses. ConclusionOverall, this assay demonstrates high sensitivities in detecting antibodies for multiple relevant MPXV and VACV antigens post-infection and post-vaccination, indicating its utility in understanding immune responses to Orthopoxviruses in current and future outbreaks and evaluating the immunogenicity of new-generation Mpox-specific vaccinations.

Proposal for fasting insulin and HOMA-IR reference intervals based on an extensive Brazilian laboratory database.

Fasting insulin and the homeostasis model assessment of insulin resistance (HOMA-IR) index are relatively simple and reliable noninvasive markers of insulin resistance (IR). Given the relevance of correctly diagnosing IR, we emphasize the importance of establishing reliable reference intervals (RIs) for these markers. This study aimed to determine the RIs of fasting insulin and HOMA-IR index in adults living in Rio de Janeiro and, secondarily, to verify potential RI differences between sexes. Serum insulin levels of 146,497 individuals (ages 20-60 years) who underwent blood sampling in the state of Rio de Janeiro were obtained retrospectively through access to an extensive laboratory database. Insulin was measured using the electrochemiluminescence immunoassay method. After applying exclusion criteria, 21,684 individuals (18,576 [86%] women) were included. The RIs were estimated using a computational mining approach that integrates a selection of R packages. The 95% RIs in women and men and in the overall population were, respectively, 2.54-13.30 μU/mL (15.3-80.12 pmol/L), 2.43-11.89 μU/mL (14.6-71.7 pmol/L), and 2.52-13.14 μU/mL (15.2-79.2 pmol/L) for fasting insulin levels and 0.39-2.86, 0.38-2.81, and 0.39-2.86 for HOMA-IR values. Despite significant differences in insulin levels and HOMA-IR index between men and women, the use of sex-specific RIs was not justified. The RIs of fasting insulin levels and HOMA-IR values found in the overall population can be applied to both sexes. Thus, for our population, we suggest the RIs of 2.52-13.14 μU/mL (15.1-78.8 pmol/L) for fasting insulin and 0.39-2.86 for the HOMA-IR index.

Highly Sensitive Electrochemiluminescence Biosensing Method for SARS-CoV-2 N Protein Incorporating the Micelle Probes of Quantum Dots and Dibenzoyl Peroxide Using the Screen-Printed Carbon Electrode Modified with a Carboxyl-Functionalized Graphene.

Obtaining stable electrochemiluminescence (ECL) emissions from a hydrophobic luminophore in aqueous solutions and designing a method without the use of an exogenous coreactant are promising for ECL biosensing. Here, a highly sensitive signal-on ECL immunoassay for the SARS-CoV-2 N protein was developed using micelles as an ECL tag. The micelles were prepared by coencapsulating the luminophore hydrophobic CdSe/ZnS quantum dots and coreactant dibenzoyl peroxide within the hydrophobic core of micelles. The ECL probe was obtained by covalently bonding a SARS-CoV-2 N protein-binding aptamer onto the micelle surface. The construction of the immunosensor was initiated by the immobilization of the anti-SARS-CoV-2 N protein antibody onto the screen-printed carbon electrode (SPCE) with a -COOH-functionalized surface. The surface functionalization of SPCEs was achieved through paste-exfoliated graphene, which was modified with a -COOH group through supramolecular-covalent scaffolds on SPCE. Upon achieving sandwich complexes on the immunosensor, an efficient ECL signal response at -1.4 V versus Ag/AgCl was obtained in phosphate buffer solution. The ECL assay was used for the sensitive determination of SARS-CoV-2 N protein with the linear range from 0.01 to 50 ng mL-1, and the detection limit was 3.0 pg mL-1. The immunosensor showed good reproducibility and stability, and the ECL immunoassay was used to determine the SARS-CoV-2 N protein in serum samples. The proposed approach to obtain micelles is versatile for the preparation of stable ECL luminophores by using hydrophobic materials, and the strategy provides an alternative for ECL bioassays based on the coreactant route.