Teruomi Tsukahara

Rice as the most influential source of cadmium intake among general Japanese population.

The objective of the present study is to examine whether rice is still a leading source of cadmium (Cd) burden among general populations in Japan. For this purpose, 10 prefectures were selected from all over Japan (including the northern- and southern-most Hokkaido and Okinawa prefecture, respectively). Cadmium levels in urine of never-smoking women (corrected for creatinine; Cd-Ucr) were compared with the rice- and wheat product-based Cd intake, which were estimated from Cd contents in rice and wheat (in the forms of bread, noodle and flour) consumed by residents in the areas, and per-capita daily consumption of rice and wheat. Stepwise multiple regression analysis taking Cd-Ucr as a dependent variable and rice- or wheat product-based Cd intakes as independent variables showed that rice was the most influential and almost exclusive variable with a partial correlation coefficient of 0.770-0.832, explaining 59-69% of total variation in Cd-Ucr. The effects of other sources including wheat were essentially negligible.

Effects of weather variability and air pollutants on emergency admissions for cardiovascular and cerebrovascular diseases

We examined the effect of ambient temperature, air pressure and air pollutants on daily emergency admissions by identifying the cause of admission for each type of stroke and cardiovascular disease using generalized linear Poisson regression models allowing for overdispersion, and controlling for seasonal and inter-annual variations, days of the week and public holidays, levels of influenza and respiratory syncytial viruses. Every 1°C decrease in mean temperature was associated with an increase in the daily number of emergency admissions by 7.83% (95% CI 2.06–13.25) for acute coronary syndrome (ACS) and heart failure, by 35.57% (95% CI 15.59–59.02) for intracerebral haemorrhage (ICH) and by 11.71% (95% CI 4.1–19.89) for cerebral infarction. An increase of emergency admissions due to ICH (3.25% (95% CI 0.94–5.51)), heart failure (3.56% (95% CI 1.09–5.96)) was observed at every 1 hPa decrease in air pressure from the previous days. We found stronger detrimental effect of cold on stroke than cardiovascular disease.

A novel device (SD-101) with high accuracy for screening sleep apnoea-hypopnoea syndrome

Background and objective:  The SD‐101 is a non‐restrictive, sheet‐like medical device with an array of pressure sensors, to detect sleep‐disordered breathing by sensing gravitational alterations in the body corresponding to respiratory movements. This study evaluated the accuracy of the SD‐101 for screening sleep apnoea‐hypopnoea syndrome (SAHS) by comparison with polysomnography.

α1-Microglobulin levels and correlation with cadmium and other metals in urine of non-smoking women among general populations in Japan

The present study was initiated to examine urinary α1-microglobulin (α1-MG-U) levels among non-smoking women in the general population in Japan. A previously established database on spot urine samples from adult woman volunteers in 10 non-polluted areas all over Japan was re-examined. The data examined were on α1-MG-U, cadmium, calcium, magnesium and zinc levels in urine (Cd-U, Ca-U, Mg-U and Zn-U, respectively), urinary creatinine (CR or cr), urine specific gravity (SG or sg), smoking habits and age. Thus, 8975 never-smoking women were selected for statistical analyses. The grand geometric mean (GM) for α1-MG-U among the population was 2.1 mg/L or 2.5 mg/g cr, depending on the correction for urine density. It was 1.1 µg/L or 1.3 µg/g cr for GM Cd-U. The inter-area difference in α1-MG-U was <1.5 mg/g cr or <0.7 mg/L; the area with the highest or lowest GM Cd-U was not always highest or lowest in GM α1-MG-U. The correlation coefficient (0.53) between log Cd-U and log α1-MG-U (both without urine density correction) became substantially smaller when the analyte levels were corrected for CR (0.25) or SG (0.26). In multiple regression analysis, the power of influence of the five independent variables (log Cd-U, Ca-U, Mg-U, Zn-U and age) in combination was small (R 2 ≦ 0.13). In contrast, logistic regression analysis suggested that α1-MG-U might be elevated as a function of an increase in Cd-U, depending on the cut-off values. Discussion was made on dose (Cd-Ucr) and response (α1-MG-Ucr) relationship based on information available in literatures to show that the increment in α1-MG-Ucr per Cd-Ucr was much greater when Cd-Ucr was large, e.g., in excess of 10 µg/g cr.

Swine-Origin Influenza A Outbreak 2009 at Shinshu University, Japan

BackgroundA worldwide outbreak of swine flu H1N1 pandemic influenza occurred in April 2009. To determine the mechanism underlying the spread of infection, we prospectively evaluated a survey implemented at a local university.MethodsBetween August 2009 and March 2010, we surveyed 3 groups of subjects: 2318 children in six schools attached to the Faculty of Education, 11424 university students, and 3344 staff members. Subjects with influenza-like symptoms who were diagnosed with swine flu at hospitals or clinics were defined as swine flu patients and asked to make a report using a standardized form.ResultsAfter the start of the pandemic, a total of 2002 patients (11.7%) were registered in the survey. These patients included 928 schoolchildren (40.0%), 1016 university students (8.9%), and 58 staff members (1.7%). The incidence in schoolchildren was significantly higher than in the other 2 groups (P < 0.0001) but there were no within group differences in incidence rate between males and females. During the period of the survey, three peaks of patient numbers were observed, in November 2009, December 2009, and January 2010. The first peak consisted mainly of schoolchildren, whereas the second and third peaks included many university students. Staff members did not contribute to peak formation. Among the university students, the most common suspected route of transmission was club activity. Interventions, such as closing classes, schools, and clubs, are likely to affect the epidemic curves.ConclusionSchoolchildren and university students are vulnerable to swine flu, suggesting that avoidance of close contact, especially among these young people, may be effective way in controlling future severe influenza pandemics, especially at educational institutions.

The effects of workplace occupational mental health and related activities on psychological distress among workers: a multilevel cross-sectional analysis.

Objective: To investigate the association of workplace occupational mental health (OMH) and related activities with psychological distress of workers in Japan. Methods: A total of 121 workplaces and their 3540 workers were surveyed using questionnaires assessing selected workplace OMH activities, demographic characteristics, psychological distress, and psychosocial work environment of the workers. A multilevel analysis was conducted. Results: Promotion of communication correlated significantly and negatively with psychological distress among workers after adjusting for the covariates (P < 0.01). Occupational mental health activities correlated marginally significantly and negatively with psychological distress (P = 0.06). Their moderating effect for the worker-level association between psychosocial work environment and psychological distress was not significant. Conclusions: The findings suggest that promotion of communication in the workplace is associated with reduced psychological distress among workers. In addition, OMH activities may also be useful in reducing psychological distress.

How the H1N1 influenza epidemic spread among university students in Japan: Experience from Shinshu University

BACKGROUND A worldwide outbreak of influenza A/H1N1 occurred in 2009. Little information is available regarding how the epidemic spread among young people, who composed the majority of individuals infected with this virus. We assessed the route of transmission of H1N1 among university students at Shinshu University, Japan. METHODS A total of 11,424 students were monitored between August 2009 and March 2010, and those who were diagnosed with confirmed, probable, or suspected H1N1 at a hospital or clinic were registered based on self-report to the university. Data including date of onset and suspected infection route were collected from the affected patients. RESULTS Of the 11,424 students, 1,016 (8.9%) were infected with H1N1. In most infected students, the suspected transmission route was associated with club activity, followed by close contact with friends and through lectures or laboratory work. After suspension of activity by clubs with more than 2 infected members, the number of infected individuals decreased. CONCLUSION H1N1 influenza spread in the university through specific routes, including club activity, close contact with friends, and lectures or laboratory work. During future outbreaks of influenza, interventions to reduce transmission through these routes may be effective infection control strategies in university students.

Seasonal Difference in Percutaneous Absorption of N,N-Dimethylformamide as Determined Using Two Urinary Metabolites

Seasonal Difference in Percutaneous Absorption of N,N‐Dimethylformamide as Determined Using Two Urinary Metabolites: Yoko TSUDA, et al. Department of Preventive Medicine and Public Health, Shinshu University School of Medicine—

The Relationship between Attitudes toward Suicide and Family History of Suicide in Nagano Prefecture, Japan

Certain attitudes toward suicide may be a risk factor for suicide among the bereaved. To explore this possibility, we examined the relationship between attitudes toward suicide and family history of suicide. We focused on two specific attitudes indicating resignation in a survey: #1 “When a person chooses to die by suicide, the suicide is inevitable” (i.e., inevitability belief); and #2 “A suicide cannot be stopped by any person, because suicide is unpreventable” (i.e., unpreventable belief). The data of 5117 fully completed questionnaires were analyzed. Logistic regression analysis revealed that the two attitudes of resignation were significantly associated with a family history of suicide. The adjusted odds ratio for #1 was 1.39 (95% CI, 1.07–1.79) for individuals having experienced suicide by a family member or relative, while that for #2 was 1.57 (95% CI, 1.27–1.95) for experiencing a suicide by a family member or relative and 1.25 (95% CI, 1.05–1.49) for experiencing a suicide by a friend, business associate, partner or other. These two attitudes of resignation toward suicide were significantly associated with a family history of suicide. These attitudes might increase suicide risk among the bereaved.

Occupational Exposure to N,N-Dimethylformamide in the Summer and Winter

We evaluated total body burden of N,N-dimethylformamide (DMF) taken through the lung and skin by personal exposure of workers to DMF and urinalysis of N-methylformamide (NMF) and N-acetyl-S(N-methylcarbamoyl)-cysteine (AMCC). A total of 270 workers were engaged in four different jobs in a workplace distant from main production lines emanating high levels of DMF. They were not required to wear any personal protective equipment including respirators or gloves. We found that log-transformed urinary levels of NMF and AMCC increased with an increase in log-transformed concentrations of exposure to DMF. Urinary levels of NMF and AMCC were significantly higher in the summer than the winter, although there was no significant seasonal difference in the concentrations of exposure to DMF. Our findings suggested that the increased urinary levels of NMF and AMCC in the summer resulted in increased skin absorption of DMF due to an increased amount of DMF absorbed by the moisturized skin under humid and hot conditions. Seasonal changes in the relative internal exposure index confirmed the present finding of enhanced summertime skin absorption of DMF. AMCC is thought to be a useful biomarker for assessments of cumulative exposure to DMF over a workweek and for evaluations of workers’ health effects.