Multicenter evaluation of the Elecsys® anti-HCV II assay for the diagnosis of hepatitis C virus infection.

Routine screening of patients at risk of hepatitis C virus (HCV) infection has become a priority given recent improvements in therapeutic options and the asymptomatic nature of most chronic infections. The aim of this study was to evaluate the performance of the Elecsys® Anti-HCV II assay, a new qualitative antibody immunoassay, compared with currently available assays, and assess its suitability for routine diagnostic testing. The sensitivity of the Elecsys® Anti-HCV II, ARCHITECT® Anti-HCV, AxSYM® HCV 3.0, PRISM® HCV, Vitros® ECi Anti-HCV, Elecsys® Anti-HCV, and ADVIA Centaur® HCV assays was compared using commercially available seroconversion panels and samples from patients known to be HCV positive and infected with HCV genotypes 1-6. Specificity was investigated using samples from blood donors, unselected hospitalized patients, and patients with potential cross-reacting factors or from high-risk groups. The Elecsys® Anti-HCV II assay detected more positive bleeds than the comparator assays, was more sensitive in recognizing early HCV infection, and correctly identified all 765 samples known to be HCV positive, regardless of genotype. The overall specificity of the Elecsys(®) Anti-HCV II assay was 99.84% (n=6,850) using blood donor samples, 99.66% (n=3,922) using samples from unselected hospitalized patients, and 99.66% (n=2,397) using samples from patients with potentially cross-reacting factors or from high-risk groups. The specificity of the Elecsys® Anti-HCV II assay was superior or equal to the comparator assays. In conclusion, the Elecsys® Anti-HCV II assay is a sensitive and specific assay suitable for routine use in the reliable detection of anti-HCV antibodies.

Effects of exercise training on endothelial progenitor cells in patients with chronic heart failure.

BACKGROUND: The enhancement of circulating endothelial progenitor cells (EPCs) obtained by exercise training can be beneficial to patients with cardiac disease. Changes in the levels and differentiation of CD34(pos)/KDR(pos) EPCs, as well as the plasma concentration of vascular endothelial growth factor (VEGF) and stromal cell-derived factor (SDF)-1 EPC-mobilizing cytokines, were evaluated in patients with chronic heart failure after 8 weeks of supervised aerobic training (SAT) and 8 weeks of subsequent discontinued SAT (DSAT). METHODS AND RESULTS: The levels of circulating EPC and EPC differentiation potential of 22 patients who underwent SAT were studied by fluorescence-activated cell sorter analysis and colony forming-unit assay, respectively. The plasma levels of VEGF and SDF-1 were measured by enzyme-linked immunosorbent assay. In response to SAT, the levels of both EPC and VEGF/SDF-1 markedly increased (P < .001 vs baseline) but returned to the baseline levels after DSAT. A similar change was observed with the EPC clonogenic potential, but on DSAT the baseline level was incompletely attained. CONCLUSIONS: In response to SAT, patients with chronic heart failure show enhanced EPC levels and clonogenic potential that is mirrored by increased plasma VEGF and SDF-1 levels. DSAT can interfere with the maintenance of training-acquired VEGF/SDF-1-related EPC levels and clonogenic potential.