[show abstract][hide abstract] ABSTRACT: The aim of this study was to evaluate the carotid arterial intima-media thickness (IMT) and its relation to clinical parameters in Japanese children. Fifty-two healthy children (39 boys and 13 girls), aged 6-14 years, were enrolled in this cross-sectional investigation study. IMT of the common carotid artery was determined using ultrasonography. We also investigated anthropometric parameters, blood pressure (BP), lifestyles and blood examinations. The mean value of IMT was 0.4 ± 0.1mm, which was lower than the normal value (1.0mm) in adults. IMT was positively correlated with age (r=0.340) and height (r=0.346) in boys, while it was positively correlated with body mass index (BMI) (r=0.584) and diastolic BP (DBP) (r=0.563) in girls. In addition, IMT was associated with sleeping hours and hours of watching television (TV) by using stepwise regression analysis. In conclusion, IMT increased with aging, and it was linked to some clinical parameters of atherosclerosis and lifestyles in children. Therefore, this reference data will be helpful for future assessment of age-related change in Japanese children in clinical practice, and IMT might be a good predictor of atherosclerosis in Japanese children.
[show abstract][hide abstract] ABSTRACT: Healthy Japan 21 (Japanese National Health Promotion in the 21st Century) was started in 2000 to promote extension of healthy life expectancy and improve health-related quality of life (HRQOL). The present study aims to describe HRQOL of Japanese subjects using the EuroQol questionnaire (EQ-5D) and investigate the influence of social background, health-related behaviors, and chronic conditions on HRQOL using representatives in Takamatsu, Japan.
Data were obtained from a 2005 Takamatsu City health survey mailed to 2,500 randomly selected Japanese individuals in Takamatsu, a medium-sized city. We examined data from 915 Japanese adults. The questionnaire addressed social background, health-related behaviors, chronic conditions, EQ-5D items, and self-rated health. The impact of social background, health-related behaviors, and chronic conditions on Japanese HRQOL was examined through multivariate regression, adjusting for age and sex.
EQ-5D scores decreased with age, particularly for respondents who were unemployed or retired. Adjusting for sex and age, the results showed that age, unemployment/retirement, feeling severe stress, and musculoskeletal and gastrointestinal diseases were significantly associated with decreased HRQOL. Conversely, sufficient sleep (7-8 h/day) and having a hobby were significantly associated with increased HRQOL.
Information is lacking regarding HRQOL in Japanese populations. This study furthers our understanding of some important determinants influencing Japanese HRQOL, using the EQ-5D in Takamatsu, Japan. Our results also resembled some findings from similar studies in other countries. We hope to use the EQ-5D with other health survey questionnaires to gather more data about HRQOL of Japanese people.
Environmental Health and Preventive Medicine 01/2011; 16(1):25-35.
[show abstract][hide abstract] ABSTRACT: Adolescents have many anxieties, and having someone to consult is important for them to maintain their mental health. This study examines: whether students have someone to consult; if they have, whether there are differences in their depressive state and in their degree of satisfaction with their school lives depending on whom they consult; and how their mental health is affected by their human relations.
Persons whom high-school students consult about their worries, Depression Self-Rating Scale for Children (DSRS-C), and satisfaction of high-school students with their school lives were surveyed in 2,646 students of public high schools in A Prefecture, and the persons selected for consultation were classified into four groups ("no one," "friends," "adults," and "friends and adults") and analyzed.
In terms of whom they consult we found that high-school students, especially girls, frequently consult "friends and adults." Mean DSRS-C score was significantly higher for those who consulted "no one" than for those who consulted "friends" or "friends and adults." Regarding hopelessness, the mean score of those who consulted "no one" was significantly higher than for those who consulted "friends and adults." Those who consulted "no one" had significantly lower mean score for satisfaction with school life than did those who consulted "friends and adults."
Most of the students selected "friends and adults" for persons to consult, but boys were more likely to have "no one" to consult. Students (boys and girls) having no one to consult are likely to be more depressive and less satisfied with their school lives.
Environmental Health and Preventive Medicine 09/2009; 15(1):57-62.
[show abstract][hide abstract] ABSTRACT: We have recently found that exposure to acute restraint stress suppresses antigen-specific antibody production, including IgE, in a murine model of allergic rhinitis. Although age-related alterations in immune responses are known, it remains unclear whether aging modulates the antibody production under stressful conditions. In this study, we set out to determine the effects of aging on antibody production under acute restraint stress in mice.
Both young and aged CBA/J mice were repeatedly sensitized intranasally with phospholipase A2 (PLA2) without adjuvants. Restraint stress was applied using uniform cylinders once a week for a continuous 8h period, on 5 occasions in total. Blood samples were taken at 0, 20 and 30 days after primary sensitization, and production of PLA2-specific antibodies and levels of IL-4, IFN-gamma, IL-10 and IL-1 beta in sera were determined by ELISA.
Repeated intranasal sensitization with PLA2 induced PLA2-specific IgE, IgG1 and IgG2a production in aged mice. We found that exposure to restraint stress significantly inhibited production of PLA2-specific IgE, IgG1 and IgG2a in aged mice. In addition, antibody production under restraint stress decreased significantly in aged mice when compared with young mice. No IL-4, IFN-gamma, IL-10 or IL-1 beta were detected in sera from non-stressed or stressed aged mice.
Aging exacerbates the immunosuppressive role of acute restraint stress in antigen-specific antibody production in mice.
[show abstract][hide abstract] ABSTRACT: To investigate the preventive effects of d-psicose, one of rare ketohexoses, on di-(2-ethylhexyl) phthalate (DEHP)-induced testicular injury, prepubertal male Sprague-Dawley rats were exposed to DEHP via their diet or orally, while under treatment with d-psicose. The rats given a diet-containing 1% DEHP alone for 7-14 days showed severe testicular atrophy accompanied by aspermatogenesis. On the other hand, those given the diet plus 2% but not 1% d-psicose-supplemented water for 14 days did not develop testicular atrophy, and exhibited an almost complete spermatogenesis. There was no significant difference in plasma mono-(2-ethylhexyl) phthalate (MEHP) levels between the d-psicose-free and d-psicose-treated groups. The testicular malondialdehyde (MDA) level after a single oral administration of 2g/kg of DEHP showed a similar pattern of increase to the plasma MEHP level and peaked in 24h suggesting a close and dose-dependent relation between plasma MEHP and testicular reactive oxygen species (ROS) levels. Pretreatment with d-psicose at a concentration of 2% and 4% resulted in an almost complete but not absolute suppression of testicular MDA production among rats administered 2g/kg of DEHP. The microarray analysis showed the induction of oxidative stress related genes including the thioredoxin, glutathione peroxidase 1 and 2, glutaredoixn 1 after 24h of the DEHP treatment in the testis. These results show that d-psicose prevents DEHP-induced testicular injury by suppressing the generation of ROS in the rat testis. This effect may be due to the direct scavenging by d-psicose of ROS generated in the testis.
[show abstract][hide abstract] ABSTRACT: To determine the biochemical effect of di-(2-ethylhexyl) phthalate (DEHP) on testes, liver, kidneys and pancreas on day 10 in the process of degeneration of the seminiferous epithelium.
Diets containing 2% DEHP were given to male Crlj:CD1(ICR) mice for 10 days. The dose of DEHP was 0.90 +/- 0.52 mg/mouse/day. Their testes, livers, kidneys and pancreata were examined for detection of mono-(2-ethylhexyl) phthalate (MEHP), nitrogen oxides (NOx) produced by peroxidation of nitric oxide (NO) with free radicals, and lipid peroxidation induced by the chain reaction of free radicals.
Histological observation and serum analysis showed the presence of severe spermatogenic disturbance, Leydig cell dysfunction, liver dysfunction and dehydration. Unexpectedly, the concentration of MEHP in the testes was extremely low compared with that in the liver. However, the concentration of the NOx in the testes was as high as the hepatic concentration. Furthermore, free radical-induced lipid peroxidation was histochemically detected in the testes but not in the liver.
The results indicate that DEHP-induced aspermatogenesis is caused by the high sensitivity of the testicular tissues to MEHP rather than the specific accumulation or uptake of circulating MEHP into the testes.
Asian Journal of Andrology 04/2007; 9(2):199-205. · 2.14 Impact Factor
[show abstract][hide abstract] ABSTRACT: This study assessed screening thresholds for determining workers exposure to toluene (Tol) by urinary Tol (Tol-U) and proposed applicable criteria for on-site settings. Participants' urine samples (n = 21) were collected at the end of the workday during the latter half of a week and the Tol-U concentration was assayed. Simultaneously, each worker's exposure dose to Tol in the breathing zone during work, Tol-TWA (time-weighted average), was measured. Tentative criteria were proposed. Level I, less than Tol-U 38 microg/l, has the least chance of exceeding Tol-OEL 50 ppm (occupational exposure limit for Tol recommended by the Japan Society for Occupational Health), probability 95% <. Level II, Tol-U 38-60 microg/l, has a low possibility of exceeding Tol-OEL. Level III, Tol-U 60-110 microg/l, has a high possibility of exceeding Tol-OEL. Level IV, more than Tol-U 110 microg/l, clearly exceeds Tol-OEL, probability 95% <.
Industrial Health 04/2006; 44(2):280-2. · 0.87 Impact Factor
[show abstract][hide abstract] ABSTRACT: Migration experiments with polystyrene were performed in two-sided contact with n-heptane and distilled water as the food simulants at temperatures of 10, 24 and 40, and 40, 60 and 90 degrees C, respectively. The surface/volume ratios in the migration cell were set at 8.04 and 10.05 dm2 l(-1) for n-heptane and distilled water, respectively. Styrene monomer, styrene dimers and styrene trimers migrating to the food simulants were determined by GC-FID analysis. Heptane fully extracted the styrene monomer and the oligomers from the polystyrene sheet, whereas in the distilled water only the migrated styrene trimers could be detected. To determine the apparent diffusion coefficient, the migration process was analysed based on Fick's law. The higher the molecular weight of the oligomers, the more significant the reduction in the diffusion coefficient. Higher molecular weight oligomers also had lower activation energy of diffusion when the temperature dependence of diffusivity was analysed by the Arrhenius equation. The diffusion coefficient of the trimers was much higher for heptane contact than for water. The activation energy of the diffusion of trimers for water contact was higher than that for heptane.
Food Additives and Contaminants 08/2005; 22(7):693-9. · 2.13 Impact Factor
[show abstract][hide abstract] ABSTRACT: Di-(2-ethylhexyl) phthalate (DEHP), now regarded as an endocrine disruptor, can experimentally induce spermatogenic disturbance in laboratory animals. Our previous study demonstrated that antioxidant vitamins (vitamins C and E) supplementation during DEHP-treatment significantly protected the rat seminiferous epithelium from DEHP-gonadotoxicity. In the present study, we gave these antioxidant vitamins to mice already having fully developed aspermatogenesis because of DEHP to determine whether or not the vitamins can cure the injured seminiferous epithelium. CD-1 male mice were fed on a DEHP-containing diet for 15 days and then fed on the DEHP-free normal diet with or without supplementation of vitamins C and E in drinking water for another 50 days. The results showed that severe aspermatogenesis was induced by the DEHP-treatment but that the damaged seminiferous epithelium spontaneously recovered whether the vitamins were provided or not. This indicates that the DEHP-induced aspermatogenesis was reversible. However, the supplementation of antioxidant vitamins significantly accelerated regeneration of the injured seminiferous epithelium, suggesting that the vitamins have a therapeutic effect on DEHP-induced aspermatogenesis.
International Journal of Andrology 11/2004; 27(5):274-81. · 3.57 Impact Factor
[show abstract][hide abstract] ABSTRACT: We carried out an investigation to clarify the real state of indoor air pollution by chlorpyrifos (termiticide) and exposure to chlorpyrifos of residents by measuring its urinary metabolite 3,5,6-trichloro-2-pyridinol (TCP) as an exposure index, such as biological monitoring.
The investigation was conducted in 43 individual houses with termiticide application (whether the termiticide was chlorpyrifos is uncertain) and 3 control houses without any termiticide application in Kagawa, Japan. Urine samples were collected from 46 healthy adult residents of the aforementioned houses.
Chlorpyrifos in indoor air in the control houses was not detected (ND<1 ng/m(3), n=3), while 41 of 43 houses with termiticide application showed 1-350 ng/m(3). Although the chlorpyrifos concentrations in these 41 houses did not exceeded the indoor air quality guideline of 1000 ng/m(3), but 3 houses were higher than the guideline 100 ng/m(3) for children in Japan. Urinary TCP concentrations of 0.1-7.8 ng/mg·creatinine were detected in 41 residents from the 41 houses where chlorpyrifos had been detected. The chlorpyrifos concentration and the urinary TCP revealed a positive correlation (r=0.5468, p<0.01, n=41).
The immediate health hazard from air born chlorpyrifos in the examined houses was negligible, but the findings suggest that it is necessary to monitor chemicals which may contaminate indoor air and to assess the risk of prolonged exposure to such chemicals. The measuring of urinary metabolite TCP of chlorpyrifos via biological monitoring would be useful, allowing comprehensive evaluation of the exposure to chlorpyrifos in indoor air.
Environmental Health and Preventive Medicine 09/2003; 8(4):139-45.
[show abstract][hide abstract] ABSTRACT: The migration of five surrogate contaminants, anthracene, benzophenone, dimethyl phthalate, methyl stearate and pentachlorophenol, from paper and paperboard into water through a polyethylene (PE) coating layer was investigated. Virgin paper and paperboard coated with PE films of 0.012 and 0.030 mm thickness were spiked evenly with standard 1-ml solutions containing 5mg of each surrogate. The spiked papers were placed in contact with the PE coating layer at 10 and 24 degrees C for 21 days. The resulting surrogate migration through the PE layer into 100ml water was measured by an analytical method developed here that used gas chromatography equipped with a flame ionization detector. Non-polar surrogates of anthracene and methyl stearate did not show any significant migration. In the case of the thin layer coating of 0.012 mm, polar water-soluble contaminants of benzophenone, dimethyl phthalate and pentachlorophenol showed an equilibrated or maximized migration after 1 day, even at a refrigerated temperature of 10 degrees C. A thick PE coating of 0.030 mm thickness delayed the progress of contaminant migration, which was also slower at lower temperature. Our results indicate that polyethylene coatings should not be seen as a complete barrier against possible contaminants in paper packaging materials under chilled or ambient conditions. Several variables such as coating thickness, temperature and suspected contaminants need to be considered to control the possible contamination risk from recycled or printed paper.
Food Additives and Contaminants 01/2003; 19(12):1200-6. · 2.13 Impact Factor
[show abstract][hide abstract] ABSTRACT: In recent years, attention has been paid to the influence of the particle fraction < or = 2.5 microns in diameter (PM2.5) among suspended particulate matter (SPM) on health. However, the present status of particle contamination in Japan has hitherto not been adequately clarified. To determine particle contamination in the outdoor air around Kagawa Medical School located on a hill in the suburb of Takamatsu City, we measured SPM according to diameter between February 1999 and January 2000.
Mass concentrations of SPM were determined using an Andersen air sampler and light scattering counts were measured using a particle counter at the same site.
Of the entire year, the total SPM concentration (PM11) was 20-30 mg/m3, and the particle fraction < or = 2.1 microns in diameter (PM2.1) accounted for 25-60%. Both the PM11 and PM2.1 concentrations were the lowest in August when the wind blew mainly from rural areas, but high in January and February when the wind blew mainly from urban areas and April when yellow sand was wind borne from China. The SPM particle count in April was markedly high when a misty aerosol containing yellow sand was extent. The SPM count for each diameter class rapidly decreased after rainfall during passage of storm fronts, but this was especially marked for smaller diameters. During the measurement period in August, air from rural areas often passed the measurement point, and the particle concentration < or = 1 micron in diameter was markedly lower than that in April.
The results suggest that the SPM levels around Kagawa Medical School located in the suburb of Takamatsu City are associated with seasonal climate and the wind direction from which the prevailing blew.
[Nippon kōshū eisei zasshi] Japanese journal of public health 08/2002; 49(7):706-12.
[show abstract][hide abstract] ABSTRACT: A survey has been conducted on subjective health status, experience of life events in recent 1 year, and health practices in the rural of Kagawa prefecture. The survey was performed from March 1995 to May 1995 with 4,013 participants, aged 40 to less than 80. The proportion of respondents who recognized their physical conditions as good decreased with age. However, the proportion of respondents who recognized their life satisfaction as good increased with age. 'Health-related' life events were the most common experienced life events for both male and female. The proportion of respondents who had life events of type 'family', 'financial', 'at workplace or job', 'in the community', and 'others' decreased with age. Men had higher proportion of 'at workplace or job' life events. The higher proportion of respondents who experienced life events recognized their subjective health status poor. For male, it observed that poor physical health status had significant association with experience of type 'in the community' and 'environmental' life events. Poor mental health status significantly associated with experience of type 'at workplace and job' life events for male, and with 'health-related' and 'family' life events for female. Poor life satisfaction significantly associated with 'at workplace or job' and 'in the community' life events for male, and with 'health related' and 'family' life events. Higher proportion of the respondents who experienced life events and recognized their subjective health status poor had low health practice scores. Logistic regression analysis showed that experience of life events and poor subjective health status had significant association with the poor health practices, especially with 'body weight changed' for both male and female.
Nippon Eiseigaku Zasshi (Japanese Journal of Hygiene) 08/2001; 56(2):514-22.
[show abstract][hide abstract] ABSTRACT: Phthalate esters, now regarded as endocrine disruptors, are widely used in the plastics industry. In particular, di-(2-ethylhexyl) phthalate (DEHP) is produced in large quantities, and is used in blood storage bags, catheters and haemodialysis instruments. Previous studies have demonstrated that treatment of rats with DEHP induces testicular atrophy with liver enlargement, although the precise nature and mechanism of the action of DEHP on these organs remains unclear. In the present study, we produced an experimental model of DEHP-induced spermatogenic disturbance in rats by feeding them a DEHP-containing diet. Liver enlargement occurred in rats fed either a 1 or 2% DEHP-containing diet. However, testicular atrophy accompanied by aspermatogenesis was induced by feeding with the 2% but not with the 1% DEHP-containing diet. This suggests that the critical DEHP dose for gonadotoxicity is higher than that for hepatotoxicity. Using the 2% DEHP-dose, the effect of simultaneous administration of antioxidant vitamins (= vitamins C and E) was next examined. It was found that the vitamin supplementation significantly prevented the testicular injury. The results suggest that antioxidant vitamins can protect the testes from DEHP-toxicity.
International Journal of Andrology 05/2000; 23(2):85-94. · 3.57 Impact Factor
[show abstract][hide abstract] ABSTRACT: Obesity is a risk factor for life-style-related diseases, and is based on three factors: genetic, environmental, and life-style. In adults, it is difficult to achieve and maintain normal body weight, so it is more effective to intervene from infancy to establish weight control. Legally required health checkups in infants of 18 and 36 months present important opportunities for obesity prevention. We consider genetic analysis to be a very important factor for obesity prevention in infancy. However, since health checkups don't involve the collection of blood, genetic analysis is considered difficult. In this study, we attempted the typing of beta3 adrenergic receptor gene polymorphism as a genetic factor from non-invasively obtained samples, buccal mucosa, hair and cerumen in 96 infants at their 18- and 36-month health checkups. Sampling buccal mucosa, hair and cerumen instead of blood caused almost no anxiety to the child or parent, so 94.1% cooperation with sampling was obtained. From buccal mucosa, about 76% of the samples could be used for the typing of polymorphism (81% by enzyme method, 59% by kit method). From hair, about 44% of the samples permitted typing of polymorphism, but from cerumen only about 4% of the samples could be used. Results from buccal mucosa and hair typed about 90% of infant polymorphism. These results suggest that this method would be practical at periodic health checkups, and would probably be applicable to mass screenings for genetic factor analysis for other diseases.
Environmental Health and Preventive Medicine 01/2000; 4(4):190-8.
[show abstract][hide abstract] ABSTRACT: We determined concentrations of chlordanes (5 chlordane compounds and 2 metabolites) in tissues and organs of mice following a prolonged exposure to Chlordane (technical grade chlordane) at levels as low as those in indoor air.After exposure to 4.22-11.36 μ g/m(3) Chlordane (total of 5 compounds) in the air for 1-6 months, 6.44-13.00 ppm chlordanes (total of 7 compounds) were detected in mice (2 tissues and 6 organs). The adipose tissue among the 2 tissues / 6 organs examined contained the highest chlordanes. The ratio of the adipose tissue chlordanes to the liver chlordanes was approximately 5.6 times, followed by the muscle (0.9), lungs (0.4), kidneys (0.4), heart (0.3), spleen (0.2) and brain (0.1). In addition, trans-nonachlor, oxychlordane and heptachlorepoxide in chlordanes were at a high level.The level of Chlordane exposure (dose) and the level of chlordanes accumulation in each tissue or organ of the mice except for the heart were closely correlated (r=0.9388-0.7130), and showed a linear relationship. The tendency of chlordanes accumulation in light of the linear relationship was adipose ≫ liver ≥ muscle.Thus, even with a low level of Chlordane in indoor air, chlordanes may be steadily accumulated in the bodies of human residents with prolonged exposure similarly. The present findings suggest that it is necessary to investigate die risk of organochlorine chemicals contamination in indoor air at prolonged exposure.
Environmental Health and Preventive Medicine 01/1999; 3(4):184-9.