The relationship between examination-related academic stress, salivary antioxidant capacity and exercise patterns of final-year Saudi dental students.

OBJECTIVE: To study the impact of examination stress on the total antioxidant capacity (TAC) of senior dental students and compare changes in TAC between students who exercise regularly and those who do not. METHODS: A questionnaire designed to evaluate physical activity levels, body mass index (BMI) and academic performance was distributed to 325 senior dental students. Of the 312 who responded, a total of 70 were enrolled in the study, of whom 60 completed the study. The students were composed of a low-activity group (n = 30), who had a Goddard-Sheppard (GS) exercise score of <25, and a high-exercise group (n = 30), who had a GS score >60. Dental Environment Stress (DES) questionnaires and salivary samples were collected at the first week of the semester and at the week of the examinations. Salivary TAC was measured using a commercially available Radical Absorbance Antioxidant Assay measurement kit (Zen-Bio ORAC™, AMS Biotechnology, Abington UK). A total of 60 students completed the study. RESULTS: A significant increase in DES values and a significant reduction in salivary TAC values were observed in the week of the examination compared to baseline scores. Although no differences were observed in the DES scores between the high-exercise and low-exercise groups, the high-exercise group showed a significantly lower reduction in examination week salivary TAC compared to their counterparts in the low-exercise group. Regression models showed a significant association between the TAC, exercise scores and DES scores in the week of the examinations. CONCLUSION: Regular exercise may help protect students against the oxidative stress associated with academic stress.

Tumor necrosis factor-α and -ß genetic polymorphisms as a risk factor in Saudi patients with vitiligo.

Vitiligo is an acquired depigmentary disorder of the skin, characterized by multiple susceptibility loci and genetic heterogeneity. The etiology of vitiligo is unknown but several hypotheses, including an autoimmune origin, have been proposed. Tumor necrosis factor (TNF)-α, a pleiotropic proinflammatory cytokine, has been shown to play a critical role in several autoimmune diseases including vitiligo. The aim of present study was to determine the association of TNF-α and -ß gene polymorphisms with vitiligo in Saudi patients. TNF-α and -ß genes were amplified in 123 Saudi patients and 200 matched controls using polymerase chain reaction to search for polymorphisms involved at positions -308, and intron 1 +252. The frequency of the TNF-α (-308) GA genotype was higher and the frequencies of the GG and AA genotypes were significantly lower in vitiligo patients compared to controls. These findings suggested that genotype GA-positive individuals at position -308 of TNF-α are susceptible to vitiligo, whereas the GG and AA genotypes might exert a protective effect. The frequency of allele A (TNF-α 2-allele) was significantly higher and that of allele G (TNF-α 1-allele) was lower in vitiligo patients compared to controls, indicating an association of allele A with susceptibility to vitiligo in Saudi patients. The results of our examination of TNF-ß (intron 1 +252) polymorphisms showed a significant increase in the frequency of the GG genotype and allele G (TNF-ß 1-allele) in vitiligo patients, suggesting a susceptibility of the GG genotype and allele G for vitiligo. By contrast, the high frequency of the GA genotype in controls might indicate a protective effect. The results of the present study strongly support a link between TNF-α (-308) and -ß (intron 1 +252) polymorphisms and vitiligo in Saudi patients.

Incidence of Herpes (Pemphigoid) Gestationis inRiyadh Armed Forces Hospital Programme.

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