Immunoturbidimetry

The concentration of calprotectin in feces is a well-studied marker of gastrointestinal inflammation in humans. However, little is known about fecal calprotectin in farm animals. In this work, we have validated an immunoturbidimetric method for fecal calprotectin (Bühlmann fCAL® turbo assay, Schönenbuch, Switzerland) in porcine and bovine fecal samples. Linearity was evaluated by serial dilution (R2  > 0.97 was obtained for both species). Accuracy was assessed by a recovery study, with results between 80 and 120% for low, medium, and high samples in both species...

OBJECTIVE: Free light chains (FLCs) can be measured in both urine (uFLC) and serum (sFLC) in immunochemistry. We aim to compare FLC levels in serum and urine assessed among healthy volunteers and measured upper reference limits (URLs) of urinary FLC to creatinine ratio (uFLC/uCr) in mg/g to compare with the manufacturer's recommended URLs. PATIENTS AND METHODS: Eligibility criteria: normal serum and urine FLC measure and negative serum/urinary immunofixation. Immunoturbidimetry was used to assess both κ and λ FLCs...

OBJECTIVES: Human heart-type fatty acid binding protein (HFABP) is a biomarker for diagnosis, risk assessment, and prognosis of acute myocardial infarction, and we aimed to establish an immunoassay for HFABP quantitation. METHODS: Human HFABP monoclonal antibodies (mAbs) were developed, evaluated by enzyme-linked immunosorbent assay, and a chemiluminescence enzyme immunoassay (CLEIA) generated. Analytical performance of the CLEIA was evaluated by measuring serum HFABP...

High-sensitivity C-reactive protein (hs-CRP) is an inflammatory biomarker and can accurately predict the development of cardiovascular disease (CVD). We synthesized a core-shell structure PPy-Au nanocomposite in situ by chemically oxidizing pyrrole (Py) with HAuCl4 and the produced Au nanoparticles realized the doping in the polymerization. Analysis of morphology and energy spectrum as well as electrochemical characterization confirmed the successful one-pot synthesis. The conductive polymers with porous structure provide abundant sites for anti-CRP binding and effectively enhanced the sensitivity of the label-free BSA/anti-CRP/PPy-Au/GCE immunosensor...

BACKGROUND: Chronic kidney disease (CKD) has a rising global prevalence and is expected to become the fifth leading cause of death by 2030. Increased albuminuria defines the early stages of CKD and is among the strongest risk factors for progressive CKD and cardiovascular disease. The value of population screening for albuminuria to detect CKD in an early phase has yet to be studied. We aimed to evaluate the effectiveness of two home-based albuminuria population screening methods. METHODS: Towards Home-based Albuminuria Screening (THOMAS) was a prospective, randomised, open-label implementation study that invited Dutch adults aged 45-80 years for albuminuria screening...

Human Serum Albumin (HSA) undergoes Post-Translational-Modifications (PTMs) leading to isoforms affecting its oncotic and non-oncotic properties. HSA is comprised of several isoforms whose abundance may vary with pathologies such as diabetes, kidney and liver diseases. Studying their impact separately may help to understand their sources and potential pathogenicity and further their evaluation as biomarkers. The present study examined semi-synthetic HSA isoforms to investigate independently their structure by means of advanced mass spectrometry techniques (LC-TOF-MS and ICP-MS), influence on the HSA binding/antioxidant activities using a binding capacity test, and potential impact on albumin quantification by a routine immunoturbidimetric assay...

OBJECTIVE:  Our study aimed to analyze the phenotype and genotype of a pedigree with inherited dysfibrinogenemia, and preliminarily elucidate the probable pathogenesis. METHODS:  The one-stage clotting method was used to test the fibrinogen activity (FIB:C), whereas immunoturbidimetry was performed to quantify the fibrinogen antigen (FIB:Ag). Furthermore, DNA sequence analysis was conducted to confirm the site of mutation. Conservation analysis and protein model analysis were performed using online bioinformatics software...

The association between plasma lipids and breast cancer (BC) has been extensively explored although results are still conflicting especially regarding the relationship with high-density lipoprotein cholesterol (HDLc) levels. HDL mediates cholesterol and oxysterol removal from cells limiting sterols necessary for tumor growth, inflammation, and metastasis and this may not be reflected by measuring HDLc. We addressed recently diagnosed, treatment-naïve BC women (n = 163), classified according to molecular types of tumors and clinical stages of the disease, in comparison to control women (CTR; n = 150) regarding plasma lipids and lipoproteins, HDL functionality and composition in lipids, oxysterols, and apo A-I...

Carbamylation is a nonenzymatic post-translational modification observed during the reaction between cyanate and amino acids and/or proteins that may occur during some pathologies such as chronic kidney disease. Evidence suggests that carbamylation may interfere with the quantification of some analytes measured using immunoturbidimetric assays. C-reactive protein (CRP) is an inflammatory response protein that is commonly quantified through immunoturbidimetry in clinical laboratories. Because the presence of modified proteins in serum can lead to impaired quantification, this study aimed to verify the impact of in vitro carbamylation on the measurement of CRP in a CRP standard solution and serum pool...

INTRODUCTION: The association between high-density lipoprotein cholesterol (HDLc) with the incidence and progression of breast cancer (BC) is controversial. HDL removes excess cholesterol from cells and acts as an antioxidant and anti-inflammatory. BC is a heterogeneous disease, and its molecular classification is important in the prediction of clinical and therapeutic evolution. Triple-negative breast cancer (TNBC) presents higher malignancy, lower therapeutic response, and survival rate...

BACKGROUND: Elevated concentrations of ferritin seem to be detrimental to human health while being quite common in the elderly. Data on dietary, anthropometric, and metabolic correlates of circulating ferritin levels in the elderly are scant. OBJECTIVES: We aimed to identify a dietary pattern, anthropometric, and metabolic traits associated with plasma ferritin status in an elderly cohort (n = 460, 57% male, age: 66 ± 12 y) from Northern Germany. METHODS: Plasma ferritin levels were measured by immunoturbidimetry...

BACKGROUND: Current WHO serum ferritin (SF) thresholds for iron deficiency (ID) in children (<12 μg/L) and women (<15 μg/L) are derived from expert opinion based on radiometric assays in use decades ago. Using a contemporary immunoturbidimetry assay, higher thresholds (children, <20 μg/L; women, <25 μg/L) were identified from physiologically based analyses. OBJECTIVE: We examined relationships of SF measured using an immunoradiometric assay from the era of expert opinion with 2 independently measured indicators of ID, hemoglobin (Hb) and erythrocyte zinc protoporphyrin (eZnPP), using data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994)...

BACKGROUND: D-dimer exhibits a certain prognostic value in hepatocellular carcinoma (HCC) patients who underwent hepatectomy and microwave ablation, while its value in estimating the clinical benefit of drug-eluting beads transarterial chemoembolization (DEB-TACE) remains unclear. Hence, this study aimed to investigate the correlation of D-dimer with tumor features, response and survival to DEB-TACE in HCC patients. METHODS: Fifty-one HCC patients treated with DEB-TACE were recruited...

Lipoprotein(a) is an inherent CVD risk biomarker that varies by race, and the levels of Lp(a) in Saudi women are relatively unexplored. We aimed to examine the effect of age and menopause on Lp(a) and explore the correlation between adiposity and cardiometabolic risk factors with Lp(a) in Saudi women. The third aim was to determine the predictors of elevated Lp(a) in this population. In this cross-sectional study of 229 women, we compared Lp(a) serum levels, adiposity indices, and lipid and glycemic profiles between menopausal groups...

BACKGROUND: Complement activation has been associated with adverse pregnancy outcomes (APO) in SLE. Pregnant women with SLE were studied to evaluate whether complement dysregulation within the first two pregnancy trimesters predicts APO. METHODS: Pregnant women fulfilled classification criteria for SLE. APO included neonatal death, preterm delivery before 36 weeks and small for gestational age newborn. Pre-eclampsia was also evaluated. Erythrocyte complement receptor 1 (ECR1) and erythrocyte-bound C4d (EC4d) were measured by flow cytometry...

Aim To investigate the relationship between C-reactive protein, anthropometric parameters, and lipids in women in the menopausal transition. Methods This cross-sectional study included 150 women divided into three groups: premenopausal (n=50), perimenopausal (n=50), and postmenopausal (n=50). All women were interviewed, body mass index (BMI) and waist-hip ratio (WHR) values were calculated, and a blood sample was taken for laboratory analysis. The values of the lipids were determined including triglycerides, total cholesterol, and high-density lipoprotein (HDL) cholesterol, while low-density lipoprotein (LDL) and very-low-density lipoprotein (VLDL) cholesterol values were obtained through formulas...

AIM: The aim of this study was to explore the association between serum lipoprotein-associated phospholipase A2 (Lp-PLA2 ) level and acute coronary syndrome (ACS), and to analyse the correlations of Lp-PLA2 concentration with high-sensitivity C-reactive protein (hs-CRP) level, body mass index (BMI), triglyceride (TG), troponin I (TNI), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) levels, and severity of coronary artery disease. METHODS: A total of 75 patients were divided into an unstable angina (UA) group ( n = 54) and an acute myocardial infarction (AMI) group ( n = 21)...

(1) Background: There are no reliable and widely available markers of functional iron deficiency (FID) in cancer. The aim of the study was to evaluate the role of transferrin (Tf) as a marker of cancer of the ovary (CrO) and related FID. (2) Methods: The study groups consisted of 118 patients with CrO and 69 control females. Blood serum iron status was determined on a Beckman Coulter AU (USA) analyzer. Tf quantification was performed by immunoturbidimetry. The relative contents of apo- and holo-Tf (iron-free and iron-saturated Tf, respectively) were determined in eight patients and a control female by immunochromatographic analysis based on the use of monoclonal single-domain antibodies (nanobodies)...

BACKGROUND: Haptoglobin (Hp), a liver derived acute phase inflammatory protein (APP), has scarcely been studied in juvenile idiopathic arthritis (JIA). Hp can occur in blood as two isoforms (Hp1 and Hp2) in precursor and mature forms. Routine clinical chemistry immunoturbidimetry does not discern these forms. It is unknown how different forms relate to disease activity in JIA. Our aims were to determine allele frequency and plasma concentrations of different Hp forms at higher versus lower JIA disease activity and compare to other APPs...

BACKGROUND: "Pneumonia Prevention No.1" belongs to 'traditional Chinese medicine prescription for prevention of viral pneumonia and influenza' was urgently formulated by Notice on Printing the Novel Coronavirus Diagnosis and Treatment Scheme for COVID-19 (Trial Version 3) and Traditional Chinese Medicine Prevention and Treatment Scheme for COVID-19 in Hubei Province (Trial). Because the prescription drug has the bidirectional regulation function of human immune function, moderate improvement of immune function can effectively resist virus invasion, while excessive immune function will produce immune overresponse...