Takeshi Suzue

The new school absentees reporting system for pandemic influenza A/H1N1 2009 infection in Japan

Objective To evaluate the new Japanese School Absentees Reporting System for Infectious Disease (SARSID) for pandemic influenza A/H1N1 2009 infection in comparison with the National epidemiological Surveillance of Infectious Disease (NESID). Methods We used data of 53,223 students (97.7%) in Takamatsu city Japan. Data regarding school absentees in SARSID was compared with that in NESID from Oct 13, 2009 to Jan 12, 2010. Results Similar trends were observed both in SARSID and NESID. However, the epidemic trend for influenza in SARSID was thought to be more sensitive than that in NESID. Conclusion The epidemic trend for influenza among school-aged children could be easily and rapidly assessed by SARSID compared to NESID. SARSID might be useful for detecting the epidemic trend of influenza.

Association between interpersonal relationship among high-school students and mental health.

ObjectivesAdolescents 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.MethodsPersons 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.ResultsIn 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.”ConclusionsMost 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.

A Method for On-Site Analysis of Urinary Benzene by Means of a Portable Gas-Chromatograph

Benzene is one of the toxic air pollutants released from automobile fuel, exhaust, tobacco smoke etc., and is commonly found in both indoor and outdoor air. Since benzene is a carcinogenic substance classified into group 1 (carcinogenic to humans) by the International Agency for Research on Cancer (IARC), it is important to assess the human health risk posed by exposure to environmental or occupational benzene. The analytical trials were performed to determine blood and urinary unchanged benzene as a specific index for low benzene exposure. But these methods require sophisticated and expensive instruments such as a gas chromatograph-mass spectrometer which can be used only in a laboratory. Moreover, benzene in biological fluids is volatilized so easily that it may cause the loss of samples during collection, transportation and preservation which is the most common cause of uncertainties. Therefore, the development of simple and specific methods to perceive benzene exposure are expected. In this study, we developed a method for on-site analysis of benzene in urine by head space-gas chromatography (HS-GC) employing a field portable GC, since on-site analysis can provide rapid data without time-consuming and loss-inducing processes such as transportation and preservation.

Possible sources of urinary benzene among nonoccupationally exposed Japanese subjects.

Unmetabolized benzene in urine (U-benzene) is known to be the best marker among the indices for the biological monitoring of occupational and environmental exposure to benzene. In this study, we determined the levels of U-benzene among Japanese university students exposed to benzene nonoccupationally and analyzed the relation between U-benzene levels and the possible factors responsible for environmental benzene exposure. In urinalysis, U-benzene concentration among 124 students was detected in the range from 18 (minimum detection limit) to 249 ng/l. The frequency distribution of U-benzene concentration peaked at 0–19 ng/l. Mean and median values of 40 and 20 ng/l for U-benzene concentration in nonoccupationally exposed subjects were lower than those in a previous study. Stepwise multiple linear regression analysis was performed to assess the potential sources of exposure to environmental benzene by analyzing the relation between U-benzene and personal, behavioral, and environmental factors. The results showed that only smoking habit (P < 0.01) and residential house age (P < 0.05) were independent determinants of U-benzene levels. In addition, U-benzene levels in relation to smoking and house age suggested that these factors could be associated with the synergistic elevation of U-benzene. The present study showed U-benzene levels among non-occupationally exposed Japanese subjects and revealed that the major exposure sources to benzene in the general environment were tobacco smoking and indoor air contamination.

Protective effect of D-psicose against testicular atrophy induced by di(2-ethylhexyl) phthalate

The pollutant di(2-ethylhexyl) phthalate (DEHP) is a suspected reproductive toxicant. To clarify the protective effect of D-psicose on DEHP-induced testicular atrophy, we exposed rats to 1% DEHP via their diet while receiving D-psicose supplementation. A significant negative correlation was found between plasma mono(2-ethylhexyl) phthalate (MEHP) concentrations and relative testicular weight in rats given the 1% DEHP-containing diet for seven days. There was, however, no significant difference in testicular weight compared with control in rats given the 1% DEHP-containing diet plus 2% D-psicose-supplemented water. Rats given the 1% DEHP-containing diet for 14 days showed severe testicular atrophy. Conversely, those given the diet plus 2 or 4% D-psicose-supplemented water did not develop testicular atrophy and exhibited complete spermatogenesis. Testicular weight was also restored almost completely by D-psicose. But, incomplete but significant protection was noted in rats receiving a 2% DEHP-containing diet plus 4% D-psicose-supplemented water for 14 days. The present study shows the almost complete protective effect of D-psicose against DEHP-induced testicular atrophy. Although the reproductive toxicity of DEHP in human beings remains unclear, D-psicose may act as a protective agent against oxidant-mediated testicular injury in mammals, including human beings.