Method comparison for CA 15-3, CA 19-9, and CA 125 determination using the new LOCI technique of Dimension Vista 1500 and Immulite 2000 XPI.

We performed method comparison for the tumor markers CA 15-3, CA 19-9, and CA 125 measured by luminescent oxygen channeling immunoassay technology on the Dimension Vista 1500 and by classic luminescence technology on the Immulite 2000 XPI. Within-day and total imprecision were determined according to Clinical and Laboratory Standards Institute (CLSI) guidelines using three serum pools at different clinically relevant levels. In addition, parallel measurements on both systems were performed in a total of 738 routine serum samples (133 CA 15-3, 395 CA 19-9, and 210 CA 125).

Method comparison for determination of the tumor markers AFP, CEA, PSA and free PSA between Immulite 2000 XPI and Dimension Vista 1500.

Background: For the Luminescent Oxygen Channeling Immunoassay (LOCI) technology as established for Dimension Vista 1500, assays have been developed for the serum tumor markers AFP, CEA, PSA and free PSA. We performed a method analysis for these parameters using the Immulite 2000 XPI.

Methods: Determination of within-day and total imprecision of the methods was carried out according to CLSI guidelines with three serum pools.

N-terminal pro-B-type natriuretic peptide in the circulation of fetuses with cardiac malformations.

Cardiac malformations with impact on loading patterns have the potential to progress to irreversible loss of ventricular function during human fetal life. N-terminal pro-B-type natriuretic peptide (nt-proBNP) is a marker of cardiac dysfunction and involved in cardiac remodeling and fibrosis. We evaluated nt-proBNP levels in the circulation of human fetuses with cardiac defects.

Reference values for N-terminal pro-B-type natriuretic peptide in fetal circulation between 20 and 34 weeks of gestation.

Objective: We aimed to investigate the range of fetal NT-proBNP values in normal pregnancy between 20 and 34 weeks of gestation.

Method: NT-proBNP was measured in 56 fetal blood samples.

Results: Mean (+ or - 2 SD) NT-proBNP concentration was 1998 (242-3754) ng/L; a significant decline occurred with advancing gestational age (p=0.

Rapid profiling of peptide stability in proteolytic environments.

The notorious degradation susceptibility of peptides is a major obstacle to their use as medicinal drugs. Assays with which the stability of peptides in complex proteolytic environments can be determined are thus indispensable for peptide drug development. Herein, we describe a new peptide proteolysis assay that meets that demand.