[Medical genetics services in VenezuelaServiços de genética médica na Venezuela].

Objective: To characterize medical genetics services in Venezuela and describe the distribution of their resources, services, technologies, and professional training.

Methods: A descriptive, documentary study of genetic services was conducted between February and November 2016, involving a review of primary documentary sources and the use of a data collection form in research institutions to obtain information on the availability of human resources, clinical care, and diagnostic services, as well as professional training. Furthermore, the Venezuelan Society of Human Genetics database was used to identify the human resources available in genetics centers.

Paradoxical roles of IFN-gamma in models of Th1-mediated autoimmunity.

T-cell responses to antigens are classified on the basis of the cytokines they produce as either Th1 (IFN-gamma, IL-2) or Th2 (IL-4, IL-10), with these Th types being indicative of either cell-mediated or antibody-mediated responses, respectively. Using this classification, T-cell responses in MHC-class-II-restricted autoimmune diseases appear to be predominantly of the Th1 type, based on the presence of high levels of IFN-gamma. This simplistic classification has recently been challenged, however, as disease incidence and severity are frequently elevated in animals that have a deficient IFN-gamma response.

Genetic ablation of interferon-gamma up-regulates interleukin-1beta expression and enables the elicitation of collagen-induced arthritis in a nonsusceptible mouse strain.

Objective: To determine whether the lack of interferon-gamma (IFNgamma) alters resistance to collagen-induced arthritis (CIA) in a nonsusceptible mouse strain, and if so, to identify changes in the antibody, cellular type II collagen (CII)-specific immune responses, and cytokine gene expression that might account for the altered susceptibility.

Methods: CIA-resistant C57BL/6 and C57BL/6 IFNgamma-/- mice were immunized with bovine CII in Freund's complete adjuvant (CFA) or in CFA alone. Animals were monitored for signs of arthritis for up to 80 days; arthritis severity was assessed visually and histologically.

Extended HLA haplotypes in a Carib Amerindian population: the Yucpa of the Perija Range.

Eleven MHC loci haplotypes have been defined among a Carib speaking Amerindian population; the Yucpa, inhabiting the northern section of the Perija Range, on the limits between Colombia and Venezuela. This tribe has been known with the name of "Motilones mansos" and is located close to the Chibcha-Paeze speaking Bari or "Motilones bravos." Seventy-three full blooded Yucpa living at the villages of Aroy, Marewa, and Peraya, were selected using a genealogy previously collected by an anthropologist and tested for Bf-C4AB complement allotypes and by serology, high resolution PCR-SSO and SBT typing for HLA class 1 and class 2 alleles.

HLA class II associations with rheumatic heart disease are more evident and consistent among clinically homogeneous patients.

Background: Discrepancies in reported HLA class II associations with rheumatic heart disease (RHD) may have been due to inaccuracies of serological typing reagents and/or lack of defined clinical classification of patients analyzed. The molecular association between HLA and RHD was investigated in patients with defined clinical outcome.

Methods And Results: Class II allele/haplotype distribution was determined in 2 groups of RHD patients (n=88) and a control group (n=59).

Risk factors in the pathogenesis of invasive group A streptococcal infections: role of protective humoral immunity.

An impressive change in the epidemiology and severity of invasive group A streptococcal infections occurred in the 1980s, and the incidence of streptococcal toxic shock syndrome cases continues to rise. The reason for the resurgence of severe invasive cases remains a mystery-has there been a change in the pathogen or in host protective immunity? To address these questions, we have studied 33 patients with invasive infection caused by genotypically indistinguishable M1T1 strains of Streptococcus pyogenes who had different disease outcomes. Patients were classified as having severe (n = 21) and nonsevere (n = 12) invasive infections based on the presence or absence of shock and organ failure.

Superantigen-based immunotherapy: a phase I trial of PNU-214565, a monoclonal antibody-staphylococcal enterotoxin A recombinant fusion protein, in advanced pancreatic and colorectal cancer.

Purpose: To establish the maximum-tolerated dose (MTD) and define the toxicities of a single-dose infusion of PNU-214565, a recombinant Escherichia coli-derived fusion protein of Staphylococcal enterotoxin A (SEA) and the Fab-fragment of the C242 monoclonal antibody in patients with advanced colorectal and pancreatic carcinomas. To investigate the capability of PNU-214565 to induce a superantigen (SAg) response resulting in cytokine production and tumor regression.

Patients And Methods: Twenty-one patients (age range, 39 to 76 years; median, 64; 12 men, nine women; 18 colorectal, three pancreatic cancers) were treated with a single 3-hour infusion of PNU-214565, with doses ranging from 0.

Extended HLA haplotypes among the Bari Amerindians of the Perija Range. Relationship to other tribes based on four-loci haplotype frequencies.

Extended HLA haplotypes among Bari Amerindians living at the Perija Range on the limits between Colombia and Venezuela have been defined using serology for class I, electrophoresis and immuno-fixation for Bf and C4, and PCR-SSO for class II loci typing. Haplotypes were assigned based on family studies and gene frequencies were calculated using a subset of less related subjects selected from the genealogy. No rare class III variants were observed, but the characteristic low HLA diversity of isolated Amerindians populations present also in the Bari extends to Bf and C4.