How, what, and why: housing, water & sanitation and wealth patterns in a cross-sectional study of the Guarani Birth Cohort, the first Indigenous birth cohort in Brazil.

Background: Despite the importance of social determinants of health, studies on the effects of socioeconomic, sanitary, and housing conditions on Indigenous child health are scarce worldwide. This study aims to identify patterns in housing, water & sanitation, and wealth (HSW) in the first Indigenous birth cohort in Brazil-The Guarani Birth Cohort. Methods: Cross-sectional study using baseline data from The Guarani Birth Cohort. We used Multiple Correspondence Analysis and Cluster Analysis. The clusters identified were ordered in increasing degrees of access to public policies and wealth, defining the patterns of HSW. Finally, we explored the association between the patterns and one of the health outcomes, hospitalization, in the birth cohort. Findings: Three patterns were identified for housing and water & sanitation, and four for wealth status, resulting in 36 combinations of patterns (3 × 3 × 4). More than 62% of children in the cohort were found with the lowest wealth patterns. The distribution of children across patterns in one dimension was not fully determined by the other two dimensions. Statistically significant associations were found between precarious households and extreme poverty, and hospitalization. Interpretation: We observed substantial heterogeneity in the distribution of children across the 36 combinations. These findings highlight that, should the dimensions of HSW be associated with health outcomes, as seen for hospitalization, they should be considered separately in multivariable models, in order to improve the estimation of their independent effects. Funding: National Council for Scientific and Technological Development, Brazil (CNPq); Oswaldo Cruz Foundation, Brazil (Fiocruz); Research Foundation of the State of Rio de Janeiro, Brazil (FAPERJ).

Deregulation of annexin-A1 and galectin-1 expression in precancerous gastric lesions: intestinal metaplasia and gastric ulcer.

OBJECTIVE: Annexin-A1 (ANXA1/AnxA1) and galectin-1 (LGALS1/Gal-1) are mediators that play an important role in the inflammatory response and are also associated with carcinogenesis. We investigated mRNA and protein expression in precancerous gastric lesions that participate in the progression cascade to gastric cancer, such as intestinal metaplasia (IM) and gastric ulcer (GU). METHODS: Quantitative real-time PCR (qPCR) and immunohistochemical techniques were used to analyze the relative quantification levels (RQ) of ANXA1 and LGALS1 mRNA and protein expression, respectively. RESULTS: Increased relative expression levels of ANXA1 were found in 100% of cases, both in IM (mean RQ = 6.22 ± 0.06) and in GU (mean RQ = 6.69 ± 0.10). However, the LGALS1 presented basal expression in both groups (IM: mean RQ = 0.35 ± 0.07; GU: mean RQ = 0.69 ± 0.09). Immunohistochemistry revealed significant positive staining for both the AnxA1 and Gal-1 proteins in the epithelial nucleus and cytoplasm as well as in the stroma of the IM and GU groups (P < 0.05) but absence or low immunorectivity in normal mucosa. CONCLUSION: Our results bring an important contribution by evidencing that both the AnxA1 and Gal-1 anti-inflammatory proteins are deregulated in precancerous gastric lesions, suggesting their involvement in the early stages of gastric carcinogenesis, possibly due to an inflammatory process in the gastric mucosa.

Polymorphisms of the DNA repair genes XRCC1 and XRCC3 in a Brazilian population

In several DNA repair genes, polymorphisms may result in reduced repair capacity, which has been implicated as a risk factor for various types of cancer. The frequency of the polymorphic alleles varies among populations, suggesting an ethnic distribution of genotypes. We genotyped 300 healthy Southeastern Brazilian individuals (262 of European ancestry and 38 of African ancestry) for polymorphisms of codons 194 and 399 of the XRCC1 base excision repair pathway gene and of codon 241 of the XRCC3 homologous recombination repair pathway gene. The allele frequencies were 0.07 for the Arg194Trp and 0.33 for the Arg399Gln codons of the XRCC1 gene and 0.35 for the Thr241Met codon of the XRCC3 gene. The genotypic frequencies were within Hardy-Weinberg equilibrium. These frequencies showed ethnic variability when compared with those obtained for different populations from several countries.

Polymorphisms of DNA repair genes XRCC1 and XRCC3, interaction with environmental exposure and risk of chronic gastritis and gastric cancer.

AIM: To evaluate the association between polymorphisms XRCC1 Arg194Trp and Arg399Gln and XRCC3 Thr241Met and the risk for chronic gastritis and gastric cancer, in a Southeastern Brazilian population. METHODS: Genotyping by PCR-RFLP was carried out on 202 patients with chronic gastritis (CG) and 160 patients with gastric cancer (GC), matched to 202 (C1) and 150 (C2) controls, respectively. RESULTS: No differences were observed among the studied groups with regard to the genotype distribution of XRCC1 codons 194 and 399 and of XRCC3 codon 241. However, the combined analyses of the three variant alleles (194Trp, 399Gln and 241Met) showed an increased risk for chronic gastritis when compared to the GC group. Moreover, an interaction between the polymorphic alleles and demographic and environmental factors was observed in the CG and GC groups. XRCC1 194Trp was associated with smoking in the CG group, while the variant alleles XRCC1 399Gln and XRCC3 241Met were related with gender, smoking, drinking and H pylori infection in the CG and GC groups. CONCLUSION: Our results showed no evidence of a relationship between the polymorphisms XRCC1 Arg194Trp and Arg399Gln and XRCC3 Thr241Met and the risk of chronic gastritis and gastric cancer in the Brazilian population, but the combined effect of these variants may interact to increase the risk for chronic gastritis, considered a premalignant lesion. Our data also indicate a gene-environment interaction in the susceptibility to chronic gastritis and gastric cancer.