Measurement of total and free prostate specific antigen (PSA) in human serum samples using an ultra-microanalytical system.

Prostate specific antigen (PSA) is a serine protease used for the screening of prostate cancer. The total portion of PSA (tPSA) can be found in its free form (fPSA), or bound to other proteins forming a stable complex. A heterogeneous sandwich-type UltraMicro Enzyme-Linked ImmunoSorbent Assay (UMELISA) has been developed for the measurement of tPSA and fPSA in human serum samples.

[Evaluation of the immobilization of one HIV-2 gp36 peptide in nitrocellulose membrane].

Introduction: antigen immobilization in solid supports is used for the development of several immunoassays. One of the first technologies developed was the protein adsorption by direct application to nitrocellulose.

Objective: to standardize the immobilization of a synthetic peptide of the HIV-2 transmembrane protein gp36 to nitrocellulose support for diagnostic purposes and to evaluate the performance parameters in a group of serum samples with recognized interesting reactivity.

[Design and evaluation of DAVIH VIH-2].

The results of the design and evaluation of DAVIH VIH-2 diagnosing system, an indirect Elisa for screening of HIV-2 antibodies, which uses a HIV-2 glycoprotein gp36 synthetic peptide in its solid phase, were exposed. In the system evaluation using WHO reference panels, 100% sensitivity, 99,81% specificity, 99,81% efficacy and very good concordance level (kappa = 0.978) were attained.

[Oral fluid and urine as alternative samples in confirmatory testing of HIV-1 infection].

The objective of this report was to evaluate oral fluid and urine as optional samples for HIV-1 confirmatory test using DAVIH-BLOT system (Laboratorios DAVIH, La Habana, Cuba), for which they were compared with their corresponding serum samples in a group of 125 individuals. In band pattern analysis, predominant antibodies in positives oral fluid and urine samples against p34, p68, gp41, gp120, were no different from their corresponding sera according to the proportion comparison test (p < 0,001). Relative sensitivity and specificity of this system were 100% in oral fluid and 98, 75% and 100% in urine samples respectively.