The cytotoxic effects evoked by exposure to environmental chemicals having electrophilic properties are often attributable to covalent attachment to intracellular macromolecules through sulfhydryl groups or enzyme-mediated redox cycling, leading to the generation of reactive oxygen species (ROS). When huge amounts of ROS form they overwhelm antioxidant defenses resulting in the induction of oxidative stress. Nitric oxide (NO) which plays a crucial role in vascular tone, is formed by endothelial NO synthase (eNOS). Since a decrease in systemic NO production is implicated in the pathophysiological actions of vascular diseases, dysfunction of eNOS by environmental chemicals is associated with cardiopulmonary-related diseases and mortality. In this review, we introduce the mechanism-based toxicities (covalent attachment and redox cycling) of electrophiles. Therefore, this review will focus on the possible mechanisms for the induction of oxidative stress and impairment of NO production caused by environmental chemicals.

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Objective: To ascertain the extent of under-utilization and insufficiency or inappropriateness in provision of health services as one of the possible causes of high mortality from pediatric pneumonia in pilot areas in Vietnam.
Method: The household survey on morbidity and treatment of acute respiratory infections, simple cough, and cold and pneumonia, was conducted in two communities with 10% sampling of the child population.
Results: Both under-treatment of “fast breathing”, a proxy for pneumonia, and over-treatment of simple cough and cold with antimicrobials by health workers, mothers, and private practitioners were common.
Conclusions: A household survey on morbidity and treatment was found to be useful to clarify actual practices in the treatment of acute respiratory infections in the community, which cannot be obtained by mere interview with health workers or mothers. Since a change of knowledge did not automatically lead to change of practice, the training of health workers, health education of mothers and provision of antimicrobials at village health stations would not guarantee improved practice of health workers and mothers. Therefore, constant supervision for health workers, continued health education of mothers and involvement of private practitioners are needed to improve the situation.

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Objective: To assess intake of folate/folic acid and food sources in Japanese female dietitians.
Subjects and Methods: We evaluated folate consumption based on four season 7 consecutive day weighed diet records (WDRs) provided by 80 Japanese female dietitians and compared the results with data from a national survey. We then selected informative foods for folate intake on the basis of 2,240 WDRs according to contribution and multiple regression analyses.
Results: Daily folate consumption (mean±SD) among Japanese dietitians was 413±158 μg from raw foods and 343±128 μg from cooked foods. Average residual rate after cooking was 84±8%. Folate intake in summer was lower than that in other seasons by analysis of variance. According to contribution and multiple regression analyses, the major contributors were vegetables, fruit and green tea.
Conclusions: Daily folate intake among Japanese female dietitians was far greater than the 200 μg recommended daily allowance for the Japanese. Irrespective of selection methods and raw/cooked foods, major folate sources were found to be green tea along with vegetables and fruit.

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Objectives: To investigate the association of smoking habits with blood pressure (BP) and intraocular pressure (IOP), and to examine whether the smoking-BP association is related to the IOP level.
Methods: This study was conducted on the basis of a cross-sectional design using annual health check-up data during one-year between August, 1999 and August, 2000 for 611 middle and old-aged Japanese residents living in Ibaraki prefecture, Japan.
Results: After adjustment for age, gender, body mass index and alcohol intake score, the proportion of hypertensives, and the mean systolic and diastolic blood pressure (SBP and DBP) of the subjects without antihypertensive medications were the highest (50.4%, 129.6 mmHg and 75.9 mmHg, respectively) in the “smokers of 25 or more cigarettes per day with intraocular pressure (IOP) >15 mmHg” of six subgroups crossed by three smoking categories (non-smokers, 1 to 24 cigarettes per day, and 25 or more cigarettes per day) and two IOP categories (less than 15 mmHg, and 15 mmHg or greater). On the other hand, the adjusted proportion of hypertensives, and the adjusted mean SBP and DBP decreased with increasing smoking category in the individuals with less than 15 mmHg of the IOP (p for trend=0.028 for proportion of hypertensives, 0.008 for the SBP, and 0.001 for the DBP, respectively).
Conclusions: Heavy smoking may be specifically related to ‘high BP accompanied by high IOP’, although the BP may be inversely associated with smoking under the condition without high IOP.

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Objectives: To evaluate the impacts of health examinations (HE) and smoking on disease mortality risk in Japan.
Methods: By using the large cohort database of a Japanese life insurance company, 720,611 subjects aged 20 to 80 years, who had contracted for life insurance between April 1, 1995 and March 31, 1998, were followed up until September 30, 1999. Cox’s proportional hazard model was used to estimate age-adjusted relative risk (RR) for disease death.
Results: After adjusting for age, disease mortality in smokers was significantly higher than that in non-smokers (men, RR 1.51, 95% CI: 1.25−1.81; women, RR 1.54, 95%CI: 1.12−2.11). Meanwhile, disease mortality in HEees (those who had got HE within the past 2 years) was significantly lower than that in non-HEees (men, RR 0.70, 95% CI: 0.56−0.88; women, RR 0.71, 95% CI: 0.54−0.92). The magnitude of the impact of HE on disease mortality risk varied according to smoking status. Non-smokers showed a significantly lower risk associated with HE, whereas smokers did not.
Conclusions: HE may allow an appreciable reduction in disease mortality, however, the reduction effect may be limited to non-smokers. Smoking cessation may be essential to improve the preventive effects of HE.

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Objectives: To examine parental influence on the development of obesity in 9-year-old Japanese children.
Methods: A 6-year follow-up study of obesity among 6,102 children born in Toyama prefecture.
Results: After adjusting for obesity at age 3, either paternal obesity or maternal obesity at the age 3 survey more than doubled the risk of obesity at age 9 in both genders. Increases in parental body mass indexes (BMIs) from the age 3 survey through the age 9 survey were significantly associated with obesity at age 9 in girls.
Conclusions: Not only parental obesity but also increases in parental BMIs were likely to be associated with development of obesity in children.

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