• International Journal of Oral Biology
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• v.39 no.1
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• pp.41-47
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• 2014

Streptococcus mutans (S. mutans) is a facultative anaerobic bacterium mainly found in the oral cavity and is known to contribute to tooth decay and gingivitis. Recent studies on intestinal microbiota have revealed that microorganisms forming a biofilm play important roles in maintaining tissue homeostasis through their own metabolism. However, the physiological roles of oral microorganisms such as S. mutans are still unclear. In our current study, we identified that constituents released from S. mutans (CR) reduce arecoline-mediated cytotoxicity without producing toxic effects themselves. Arecoline, as a major alkaloid of areca nut, is known to mediate cytotoxicity on oral epithelial cells and induces a sustained intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) increase that is cytotoxic. The exposure of human gingival fibroblast (HGF) cells to CR not only inhibited the sustained $[Ca^{2+}]_i$ increase but also the initial $[Ca^{2+}]_i$ elevation. In contrast, CR had no effects on the gene regulation mediated by arecoline. These results demonstrate that S. mutans has physiological role in reducing cytotoxicity in HGF cells and may be considered a novel pharmaceutical candidate.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8673-8678
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• 2014

Purpose: This study aimed to determine the association between tobacco consumption (kretek) and betel quid chewing with oral cancer risk. Materials and Methods: A total of 81 cases of oral cancers were matched with 162 controls in this hospital-based study. Information on sociodemographic characteristics and details of risk habits (duration, frequency and type of tobacco consumption and betel quid chewing) were collected. Association between smoking and betel quid chewing with oral cancer were analysed using conditional logistic regression. Results: Slightly more than half of the cases (55.6%) were smokers where 88.9% of them smoked kretek. After adjusting for confounders, smokers have two fold increased risk, while the risk for kretek consumers and those smoking for more than 10 years was increased to almost three-fold. Prevalence of betel quid chewing among cases and controls was low (7.4% and 1.9% respectively). Chewing of at least one quid per day, and quid combination of betel leaf, areca nut, lime and tobacco conferred a 5-6 fold increased risk. Conclusions: Smoking is positively associated with oral cancer risk. A similar direct association was also seen among betel quid chewers.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.12
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• pp.5075-5080
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• 2016

Purpose: Factors associated with ever-use and differences between ever-users and non-users of tobacco among adolescent school students from low income families in Mumbai were assessed. Materials and Methods: A self-administered questionnaire, completed by 1918 students from grades 7, 8 and 9 in 12 schools managed by the city municipal corporation in July 2015, gathered data on socio-demographic characteristics, tobacco use and tobacco-related knowledge, attitudes and beliefs. Results: Although only 1% of respondents thought tobacco was cool, nearly 35% were unaware of associations between tobacco use and health problems. Male students were almost twice as likely (OR=2.5, P <= 0.05) to have ever used tobacco compared to females and Supari (areca nut) users were eight times more likely (OR=8.99, P < 0.001) than Supari non -users. Tobacco-users were more likely to agree with statements: 'People who use tobacco have more friends' (OR=2.8, P = 0.004), 'Smoking relieves stress' (OR=5.6, P = 0.002) and 'It is possible to purchase any tobacco product within 100 yards of school' (OR=10.8, P < 0.001). Conclusion: This study highlights the gains made by tobacco prevention campaigns in that almost all students did not consider tobacco as cool or a stress reliever. However, they still need education about health consequences of tobacco-use. In addition, Supari use has to be addressed in school-based tobacco prevention and cessation initiatives. Furthermore, programs must also address perceptions and norms related to peers and tobacco use and ensure active implementation of existing laws. Such integrated measures will help ensure tobacco-free spaces around schools.