No abstract

Backgroundepigenomes can be influenced by environmental factors leading to the development of diseases.ObjectiveTo investigate the influence of sun exposure on global DNA methylation and hydroxymethylation status and at specific sites of the miR-9-1, miR-9-3 and MTHFR genes in skin samples of subjects with no history of skin diseases.MethodsSkin samples were obtained by punch on sun-exposed and sun-protected arm areas from 24 corpses of 16-89 years of age. Genomic DNA was extracted from skin samples that were ranked according to Fitzpatrick's criteria as light, moderate, and dark brown. Global DNA methylation and hydroxymethylation and DNA methylation analyses at specific sites were performed using ELISA and MSP, respectively.ResultsNo significant differences in global DNA methylation and hydroxymethylation levels were found among the skin areas, skin types, or age. However, gender-related differences were detected, where women showed higher methylation levels. Global DNA methylation levels were higher than hydroxymethylation levels, and the levels of these DNA modifications correlated in skin tissue. For specific sites, no differences among the areas were detected. Additional analyses showed no differences in the methylation status when age, gender, and skin type were considered; however, the methylation status of the miR-9-1 gene seems to be gender related.Study limitationsthere was no separation of dermis and epidermis and low sample size.Conclusionsun exposure does not induce changes in the DNA methylation and hydroxymethylation status or in miR-9-1, miR-9-3 and MTHFR genes for the studied skin types.

Leprosy patients may present with immune system impairment and have a higher hepatitis B virus (HBV) seroprevalence, justifying the investigation of occult HBV infection in these individuals. The aim of this study was to verify the frequency and the clinical factors associated with occult HBV infection in leprosy patients. Between 2015 and 2016, leprosy patients from a reference center in Brazil were interviewed to assess clinical data. Blood samples were collected for the screening of HBV serological markers using enzyme‐linked immunosorbent assay. Patients with negative hepatitis B surface antigen (HBsAg) that had positive anti‐HBc and/or anti‐HBs were selected for HBV DNA detection using real‐time polymerase chain reaction. SPSS was used for data analysis. Among 114 selected patients, six were identified with occult infection (5.3%) and five of them with multibacillary leprosy. Three patients with occult infection had a history of a type 2 reaction (P = 0.072; OR, 4.97; 95% CI, 0.87‐28.52). Only two patients with occult infection had isolated anti‐HBc, while three had isolated anti‐HBs, including those with the highest HBV DNA titers. In conclusion, in leprosy patients with negative HBsAg and positive anti‐HBc and/or anti‐HBs, occult HBV infection occurs in 5.3% and can be found even in patients with isolated anti‐HBs.

No abstract

No abstract