ABSTRACT
BACKGROUND/AIMS: Nail biting is a common oral habit in children and young adults. However, its effect on the oral carriage of Enterobacteriaceae is unclear. The purpose of the study was to evaluate the differences in prevalence of Enterobacteriaceae in saliva samples from subjects with and without a nail-biting habit. METHODS: Saliva samples were taken from 25 subjects who were nail-biters and 34 subjects with no oral habit. The mean chronological age for all subjects was 13.5 +/- 1.9 years. The saliva samples were studied microbiologically. A Pearson chi-squared test was performed to compare the prevalence of Enterobacteriaceae in the saliva samples of the subjects with and without nail-biting habits. RESULTS: Statistically significant differences were found in the prevalence of Escherichia coli and total Enterobacteriaceae between both groups (P < 0.001). E. coli, Enterobacter aerogenes, Enterobacter cloacae and Enterobacter gergoviae were found in the saliva samples of 19 of the 25 nail-biting subjects (76%), whereas E. coli, E. aerogenes and E. cloacae were detected in the saliva samples of only nine of the 34 subjects who were not nail-biters (26.5%). CONCLUSION: According to the results of the present study, the Enterobacteriaceae were more prevalent in the oral cavities of children with nail-biting habits than in children with no oral habit.
Subject(s)
Enterobacteriaceae/isolation & purification , Mouth/microbiology , Nail Biting , Adolescent , Child , Dental Plaque Index , Enterobacter/classification , Enterobacter/isolation & purification , Enterobacter aerogenes/isolation & purification , Enterobacter cloacae/isolation & purification , Escherichia coli/isolation & purification , Female , Humans , Male , Nail Biting/adverse effects , Oral Hygiene , Saliva/microbiologyABSTRACT
Diabetes mellitus, the most common serious metabolic disorder, is characterized by functional and structural changes in the peripheral and central nervous systems. Glial cells provide structural and metabolic support for retinal neurons. During diabetes, one of the early pathogenic events is retinal glial reactivity. We studied the effects of melatonin, which is known to reduce oxidation-based neurotoxicity, on glial reactivity and lipid peroxidation in the retina of diabetic rats. Diabetes was induced by a single injection of streptozotocin (STZ), and these diabetic rats were treated daily either with melatonin (10 mg/kg) or saline vehicle. After 6 weeks of diabetes, we determined the extents of lipid peroxidation and glial reactivity in retina. Lipid peroxidation, measured on the basis of malondialdehyde and 4-hydroxyalkenals concentrations, was increased in diabetic rats (p<0.01) and this increase was prevented by melatonin treatment (p<0.05). Furthermore, gial reactivity, determined immunohistochemically from the levels of glial fibrillary acid protein (GFAP), was also increased significantly (p<0.01). Melatonin administration partially prevented this increase in GFAP content (p<0.05). In conclusion, glial reactivity is an early pathogenic event in diabetic retina and both reactive gliosis and accumulation of malondialdehyde and 4-hydroxyalkenals are prevented by melatonin supplementation.
