Blood-Biomarkers for Glucose Metabolism in Preterm Infants.

This was an exploratory, prospective, longitudinal, cohort study that aimed to establish "healthy" reference levels related to growth parameters and glucose metabolites in preterm infants. This was conducted to further investigate growth and metabolic disturbances potentially related to neonatal illness. The study sample consisted of 108 preterm infants born before 32 weeks in 2018-2019 in the Capital Region of Denmark. Repetitive blood samples were acquired at the neonatal wards, while clinical data were obtained from the regional hospital medical record system. Thirty-four "healthy" preterm infants (31%) were identified. The "ill" infants were divided into four subgroups dependent on gestational age and small for gestational age. Reference levels for the growth parameters and metabolic biomarkers glucose, albumin, and adiponectin, and two glucose control indicators, glycated albumin and fructosamine, were determined for the "healthy" and "ill" subgroups. The "ill" extremely preterm infants had increased glucose levels (mean difference 0.71 mmol/L, 95% CI 0.23; 1.18 mmol/L) and glycated albumin (corrected; %) (mean difference 0.92 mmol/L, 95% CI 0.38 mmol/L;1.47 mmol/L) compared to the "healthy" infants. In "ill" extremely preterm infants and "ill" very preterm infants born small for gestational age, levels of biomarkers containing proteins were decreased. In the "Ill" extremely preterm infants and infants born small for gestational age, postnatal growth was continuously decreased throughout the postconceptional period. The short-term glucose-control indicator, glycated albumin (corrected; %), reflected well the high glucose levels due to its correction for the depleted plasma-protein pool.

Sensitivity and performance of three novel quantitative assays of SARS-CoV-2 nucleoprotein in blood.

To assess if SARS-CoV-2 (COVID-19) systemic disease can be determined by available nucleoprotein assays, we compared the performance of three commercial SARS-CoV-2 nucleoprotein (N) assays in plasma. A total of 272 plasma samples collected in the period November-December 2021 were analyzed by the methods Simoa SARS CoV-2 N Protein Advantage Kit [Quanterix Simoa], Solsten SARS-CoV-2 Antigen enzyme immunosorbent assay (ELISA) [Solsten ELISA], and Elecsys SARS-CoV-2 Antigen electrochemiluminescence immunoassay [Elecsys ECLIA]. Additionally, a dilution series of inactivated virus culture was analyzed by the three assays. The SARS CoV-2 PCR-status was not known for the patients. Linear correlation in the pairwise correlation between assays as well as linearity of dilution series of inactivated virus culture was estimated by Spearman score. Sensitivity and specificity were estimated by pairwise comparison. The three assays showed poor agreement on patient samples with regards to concentration. Performance on virus culture was excellent but with different level of detection (LOD). Positive vs negative results show comparable sensitivity and specificity of Quanterix Simoa and Solsten ELISA, with a higher LOD in Elecsys ECLIA and thus lower sensitivity and high specificity. N by all tested assays can be used as a marker for systemic COVID-19 disease.

Daily monitoring of viral load measured as SARS-CoV-2 antigen and RNA in blood, IL-6, CRP and complement C3d predicts outcome in patients hospitalized with COVID-19.

OBJECTIVES: We hypothesized that the amount of antigen produced in the body during a COVID-19 infection might differ between patients, and that maximum concentrations would predict the degree of both inflammation and outcome for patients. METHODS: Eighty-four hospitalized and SARS-CoV-2 PCR swab-positive patients, were followed with blood sampling every day until discharge or death. A total of 444 serial EDTA plasma samples were analyzed for a range of biomarkers: SARS-CoV-2 nuclear antigen and RNA concentration, complement activation as well as several inflammatory markers, and KL-6 as a lung marker. The patients were divided into outcome groups depending on need of respiratory support and death/survival. RESULTS: Circulating SARS-CoV-2 nuclear antigen levels were above the detection limit in blood in 65 out of 84 COVID-19 PCR swab-positive patients on day one of hospitalization, as was viral RNA in plasma in 30 out of 84. In all patients, complete antigen clearance was observed within 24 days. There were definite statistically significant differences between the groups depending on their biomarkers, showing that the concentrations of virus RNA and antigen were correlated to the inflammatory biomarker levels, respiratory treatment and death. CONCLUSIONS: Viral antigen is cleared in parallel with the virus RNA levels. The levels of antigens and SARS-CoV-2 RNA in the blood correlates with the level of IL-6, inflammation, respiratory failure and death. We propose that the antigens levels together with RNA in blood can be used to predict the severity of disease, outcome, and the clearance of the virus from the body.

Evaluation of OneTouch Verio(®), a new blood glucose self-monitoring system for patients with diabetes.

INTRODUCTION: Self-monitoring of blood glucose (SMBG) is important in diabetes management. Reliable and user-friendly instruments are essential. OneTouch Verio(®) is a new blood glucose concentration-measuring system designed to be used by patients with diabetes and healthcare professionals. The objective of the present study was to evaluate the analytical performance of the OneTouch Verio(®). METHOD: The OneTouch Verio(®) was evaluated by the Scandinavian evaluation of laboratory equipment for primary healthcare (SKUP) according to a protocol based on ISO 15197 and the American Diabetes Association (ADA) quality goals. Blood samples were collected and measured on the OneTouch Verio(®) by laboratory personnel and patients with diabetes (n = 91, randomized into groups receiving personal training or mail instructions for the OneTouch Verio(®) system). Results were compared to a validated routine method, imprecision and bias were calculated. User-friendliness was evaluated with a questionnaire. RESULTS: Quality specifications for blood glucose concentration monitoring systems according to ISO 15197 were fulfilled. The mean coefficients of variation (CV%) of repeatability was 3.4% when tested by laboratory personnel and within the goal of imprecision suggested by ADA. Mean CV% of repeatability for patient self-monitoring was 5.0% and 5.1% in the training- and the mail group, respectively. Total error was 6.4-10.0%. The OneTouch Verio(®) showed no hematocrit interference or variation between strip lots. CONCLUSION: The OneTouch Verio(®) displayed sufficient analytical quality and satisfactory user-friendliness. It is suitable for point-of-care testing of blood glucose concentration when handled by patients and healthcare professionals.

The influence of tissue ischemia on biomarker expression in colorectal cancer.

The aim of the present study was to investigate the influence of fixation delay and the perioperative ischemia on hypoxia inducible factor (HIF)-1α gene expression, HIF-1α protein expression, and immunohistochemical (IHC) expression of HIF-1α, GLUT-1, Bcl-2, and Ki-67 in colorectal cancer. The study included 25 surgically removed colorectal tumors. Three sets of samples were collected readily after removal and exposed to 0, 30, and 60 minutes of delay of fixation or freezing. The perioperative ischemia time was registered. In each set of the samples, HIF-1α gene expression was analyzed by quantitative real time polymerase chain reaction, protein concentration of HIF-1α was assessed by enzyme-linked immunosorbent assay, and IHC staining of HIF-1α, GLUT-1, Bcl-2, and Ki-67 was performed. Preoperative formalin-fixed paraffin-embedded biopsies and whole sections of the entire tumor were analyzed by IHC. We found that the HIF-1α gene expression, HIF-1α protein concentration, and IHC expression of HIF-1α, GLUT-1, Ki-67, and Bcl-2 were not systematically affected by either the fixation or freezing delay of the tissue, the perioperative ischemia time, or the total ischemia time (perioperative ischemia+delay of fixation or freezing) in colorectal tumors. However, the intraindividual variation was quite large, which may question the use of individually, non-standardized-handled single biopsies or small tissue samples for analysis of often rather heterogenously expressed biomarkers.

The importance of -460 C/T and +405 G/C single nucleotide polymorphisms to the function of vascular endothelial growth factor A in colorectal cancer.

PURPOSE: The present study investigated the functional influence of the single nucleotide polymorphisms (SNPs) -460 C/T and +405 G/C at vascular endothelial growth factor A (VEGF-A), mRNA and protein levels in colorectal cancer (CRC) and normal colorectal tissue. METHODS: Blood and tissue were collected from 113 patients surgically resected for colorectal cancer. SNPs were analysed from genomic DNA by PCR, the VEGF-A gene expression analysis was performed by RT-PCR and protein analysis by ELISA. RESULTS: The T-allele in the -460 C/T SNP and the C-allele in the +405 G/C SNP were associated with significantly lower VEGF-A protein levels in normal colorectal tissue. There were no differences in protein levels in the malignant tissue according to genotypes. No differences were observed at the gene expression levels either. CONCLUSION: The results indicate that the two SNPs have a functional influence on the VEGF-A protein levels in normal colorectal tissue. The possible clinical implications of the findings need further investigation.

Quantitative analysis of vascular endothelial growth factor receptors 1 and 2 in colorectal cancer.

Vascular endothelial growth factor A (VEGF-A) is a key regulator of angiogenesis that binds to the receptors VEGFR-1 and VEGFR-2. It is well known that VEGF-A levels are increased in colorectal cancer (CRC) tissue compared to normal colorectal tissue, but little is known regarding the expression of the VEGFR-1 and -2 receptors. The aim of the present study was to perform a quantitative analysis of VEGFR-1 and -2 at the mRNA and protein level in tumour and normal colorectal tissue from CRC patients. Tissues were collected from 110 patients who underwent surgical resection for CRC. Receptor status was analysed at the gene expression level by real time RT-PCR using ß-2-microglobulin and ß-actin as reference genes. Protein analysis was performed using the ELISA technique. Gene expression and protein concentrations of VEGFR-1 and -2 were significantly increased in CRC tissue compared to normal colorectal tissue (P<10-6 for both receptors). An association between the gene expression of VEGFR-2 in CRC tissue and disease stage was detected (P=0.055). Significant correlations were also found between the gene expression of VEGFR-1 and -2 in CRC tissue and normal colorectal tissue (P<10-4). The gene expression and protein concentrations of VEGFR-1 and -2 were increased in CRC tissue compared to normal colorectal tissue, indicating that both receptors are important in CRC. The clinical implications of these findings require further investigation.

HER-2 protein concentrations in breast cancer cells increase before immunohistochemical and fluorescence in situ hybridization analysis turn positive.

BACKGROUND: The level of HER-2/neu in breast cancer cells is normally measured by immunohistochemistry (IHC) and/or fluorescence in situ hybridization (FISH). It determines whether patients should be treated with trastuzumab (Herceptin). In this study, HER-2 protein in breast cancer tissue was measured using a quantitative method. METHODS: Tissue samples of malignant and adjacent benign breast tissue were collected from 118 consecutive women admitted for surgical treatment of breast cancer. The HER-2 protein concentration was determined by 2 HER-2 assays: ELISA and the Bayer ADVIA Centaur assay. Paraffin-embedded tissue sections of the corresponding tumors were analyzed by IHC and FISH. RESULTS: Increased HER-2 concentrations in cancer tissue were found compared to autologous reference tissue (p<0.0001, Wilcoxon test) and normal breast tissue (p<0.0001, Mann-Whitney test). Good concordance rates were observed between the methods: 95.8% for IHC and FISH; 86.4% for IHC and ELISA; and 87.3% for FISH and ELISA. The HER-2 positivity rate was determined to 26.3% by ELISA, 12.7% by IHC and 16.9% by FISH. No correlation was found with tumor grade, axillary node status or serum HER-2 levels. CONCLUSIONS: Detection of HER-2 overexpression by measuring HER-2 in tissue extracts by ELISA seems to be more sensitive than IHC and FISH. This suggests that some patients deprived of Herceptin treatment may benefit from this treatment and may also explain the conversion phenomenon from HER-2-negative to HER-2-positive observed in relapse and metastatic disease.