Influence of smoking on methylation and hydroxymethylation levels in global DNA and specific sites of KRT14, KRT19, MIR-9-3 and MIR-137 genes of oral mucosa.

Objective: The aim of this study was to investigate the influence of smoking on the methylation and hydroxymethylation status of global DNA and specific sites of KRT14, KRT19, miR-9-3 and miR-137 genes in the healthy oral mucosa.

Methods: Samples of oral epithelial cells were collected using mouthwash from a population of former and current smokers and those who had never smoked. Genomic DNA was extracted, and global DNA methylation and hydroxymethylation was performed using an ELISA-based technique; DNA methylation at specific sites was performed using Methylation-Specific PCR (MSP) (KRT14, miR-9-3 and miR-137) or Methylation-Sensitive Restriction Enzymes (MSRE) (KRT19).

Endocrine cells and nerve ganglia of the small intestine of the Opossum Didelphis aurita Wied-Neuwied, 1826 (Mammalia: Didelphidae).

The nervous and endocrine systems jointly control intestinal movements, secretions of their glands and also participate of the processes of nutrient digestion and absorption. Therefore, the central objective of this study was to verify the existence of a possible relationship between the number of nervous cells and ganglia of the submucosal and myenteric plexuses and the number of endocrine cells in the small intestine of adult D. aurita.