No evidence for association of the CD40, CD40L and BLYS polymorphisms, B-cell co-stimulatory molecules, with Brazilian endemic Plasmodium vivax malaria

Background: Plasmodium vivax is the most prevalent malaria species in Brazil. The parasite-host coevolutionary process can be viewed as an 'arms race', in which adaptive genetic changes in one are eventually matched by alterations in the other. Methods: Following the candidate gene approach we analyzed the CD40, CD40L and BLYS genes that participate in B-cell co-stimulation, for associations with P. vivax malaria. The study sample included 97 patients and 103 controls. We extracted DNA using the extraction and purification commercial kit and identified the following SNPs: 21C.T in the CD40 gene, 2726T.C in the CD40L gene and the 2871C.T in the BLyS gene using PCR-RFLP. We analyzed the genotype and allele frequencies by direct counting. We also compared the observed with the expected genotype frequencies using the Hardy-Weinberg equilibrium. Results: The allele and genotype frequencies for these SNPs did not differ statistically between patient and control groups. Gene-gene interactions were not observed between the CD40 and BLYS and between the CD40L and BLYS genes. Overall, the genes were in Hardy-Weinberg equilibrium. Significant differences were not observed among the frequencies of antibody responses against P. vivax sporozoite and erythrocytic antigens and the CD40 and BLYS genotypes. Conclusions: The results of this study show that, although the investigated CD40, CD40L and BLYS alleles differ functionally, this variation does not alter the functionality of the molecules in a way that would interfere in susceptibility to the disease. The variants of these genes may influence the clinical course rather than simply increase or decrease susceptibility. © Royal Society of Tropical Medicine and Hygiene 2013. All rights reserved.

Association of the Leptin Gene with Carcass Characteristics in Nellore Cattle

Advances in DNA technology have created biotechnological tools that can be used in animal selection and new strategies for increasing herd productivity and quality. The objective of the present work was to associate the genotypes of leptin gene exon 2 polymorphisms with productive traits in Nellore cattle. Blood was collected from Nellore males and PCR-RFLP reactions were performed with the restriction enzymes ClaI and Kpn2I. The gene frequencies resulting from digestion by ClaI were 0.60 and 0.40 for allele A and T, respectively; the genotypic frequencies were AA = 0.20 and AT = 0.80. The gene frequencies from digestion by Kpn2I were 0.81 for allele C and 0.194 for allele T; the genotypic frequencies were CC = 0.62 and CT = 0.38. The populations in both cases were not in Hardy-Weinberg equilibrium (p > 0.05), and the TT genotype was not found. Significant associations were noted between leptin gene exon 2 polymorphisms and five productive traits in Nellore cattle: carcass fat distribution, the intensity of red muscle coloration, pH, marbling, and post-slaughter fat thickness. © 2013 Copyright Taylor and Francis Group, LLC.

The Association of Caribbean States (ACS): a commentary

Includes bibliography

Public administration problems in Latin America and solutions from the United Nations of America

Includes bibliography

Proposals for the liberalization of trade and investment in the Association of Caribbean States (ACS)

Includes bibliography

Notes on the Colloquium of the Association of Caribbean Historians on "Political Ideas and Tendencies in the History of the Caribbean" and "Cities in the Caribbean"

Comentarios sobre el 8o Coloquio de la Asociacion de Historiadores Caribenos en el que se analizo las ideas politicas y las ciudades en la historia del Caribe

Estudio económico de los Estados Unidos 1987 = Economic survey of the United States of America 1987

Incluye Bibliografía

Estudio económico de los Estados Unidos, 1988 = Economic survey of the United States of America, 1988

Incluye Bibliografía

Association of killer cell immunoglobulin-like receptor polymorphisms with chronic hepatitis C and responses to therapy in Brazil

ABSTRACT: Soroprevalence for Hepatitis C virus is reported as 2.12% in Northern Brazil, with about 50% of the patients exhibiting a sustained virological response (SVR). Aiming to associate polymorphisms in Killer Cell Immunoglobulin-like Receptors (KIR) with chronic hepatitis C and therapy responses we investigated 125 chronic patients and 345 controls. Additionally, 48 ancestry markers were genotyped to control for population stratification. The frequency of the KIR2DL2 and KIR2DL2+HLA-C^Asp80 gene and ligand was higher in chronic infected patients than in controls (p < 0.0009, OR = 3.4; p = 0.001, OR = 3.45). In fact, KIR2DL3 is a weaker inhibitor of NK activity than KIR2DL2, which could explain the association of KIR2DL2 with chronic infection. Moreover, KIR2DS2 and KIR2DS2+HLA-C^Asp80 (p < 0.0001, OR = 2.51; p = 0.0084, OR = 2.62) and KIR2DS3 (p < 0.0001; OR = 2.57) were associated with chronic infection, independently from KIR2DL2. No differences in ancestry composition were observed between control and patients, even with respect to therapy response groups. The allelic profile KIR2DL2/KIR2DS2/KIR2DS3 was associated with the chronic hepatitis C (p < 0.0001; OR = 3). Furthermore, the patients also showed a higher mean number of activating genes and a lower frequency of the homozygous AA profile, which is likely secondary to the association with non-AA and/or activating genes. In addition, the KIR2DS5 allele was associated with SVR (p = 0.0261; OR = 0.184).The ancestry analysis of samples ruled out any effects of population substructuring and did not evidence interethnic differences in therapy response, as suggested in previous studies.