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The article presents a study related to joint effect of radiation and diet. lonising radiation is a known risk factor of cancer, while fruit and vegetables consumption is thought to reduce the risk of cancer. A cohort of 36,228 atomic bomb survivors of Hiroshima and Nagasaki, for whom radiation dose estimates were currently available, had their diet assessed in 1980. The follow up period for cancer mortality was 20 years. In the additive model, a daily intake of fruit and vegetables significantly reduced the risk of cancer deaths by 13%, compared with an intake of once or less per week.

In Japan, cohort studies on stroke have been mainly conducted in rural areas, with few studies comparing stroke mortality between urban and rural areas. We aimed to explore urban-rural difference in stroke mortality throughout Japan using a representative sample of the general Japanese population, the NIPPON DATA80. This study included 9309 subjects (4080 men and 5229 women) aged 30 years or older who were residents of 294 areas in 211 municipalities of Japan in 1980 and followed-up until 1999. Population size of the municipality in which the aforementioned areas were located was used to distinguish between urban and rural areas, because municipalities in Japan are classified as village, town or city principally by population size. We applied a multilevel logistic regression model to take into account the hierarchical data structure of individuals (subjects) (level 1) nested within areas (level 2), and then calculated odds ratios and 95% confidence intervals (CIs) of deaths from total stroke. Statistically significant variance between areas was not observed in men but was in women. Age-adjusted odds ratios of the areas in the medium (population30,000 and <300,000) and small municipalities (<30,000) compared with the areas in the large municipalities (300,000) were 1.31 and 1.40 in men, and 1.32 and 1.62 in women, respectively. Multivariate-adjusted odds ratios (adjusted for age, body mass index, total cholesterol, diabetes, hypertension, current smoking, and daily alcohol consumption) of the areas in the medium and small municipalities compared with the areas in the large municipalities were 1.29 and 1.36 in men, and 1.34 and 1.68 in women, respectively. In conclusion, stroke mortality tended to be higher in rural areas than in urban areas in Japan, especially among women. [ABSTRACT FROM AUTHOR]

Background: Radiation-induced bone sarcoma has been associated with high doses of ionizing radiation from therapeutic or occupation-related exposures. However, the development of bone sarcoma following exposure to lower doses of ionizing radiation remains speculative.Methods: A cohort analysis based on the Life Span Study (n = 120,321) was performed to assess the development of bone sarcoma in atomic-bomb survivors of Hiroshima and Nagasaki followed from 1958 to 2001. The excess relative risk per gray of ionizing radiation absorbed by the bone marrow was estimated. Additional subject demographic, survival, and clinical factors were evaluated.Results: Nineteen cases of bone sarcoma (in eleven males and eight females) were identified among the 80,181 subjects who met the inclusion criteria, corresponding to an incidence of 0.9 per 100,000 person-years. The mean ages at the time of the bombing and at diagnosis were 32.4 and 61.6 years, respectively. The mean bone marrow dose was 0.43 Gy. Osteosarcoma was the most commonly identified bone sarcoma. The most common bone sarcoma site was the pelvis. The overall unadjusted five-year survival rate was 25%. A dose threshold was found at 0.85 Gy (95% confidence interval, 0.12 to 1.85 Gy), with a linear dose-response association above this threshold. The linear slope equaled an excess relative risk of 7.5 per Gy (95% confidence interval, 1.34 to 23.14 per Gy) in excess of 0.85 Gy.Conclusions: On the basis of what we believe is one of the longest and largest prospective studies assessing the development of bone sarcoma in individuals exposed to ionizing radiation, it appears that the development of radiation-induced bone sarcoma may be associated with exposure to much lower doses of ionizing radiation than have previously been reported. Such new insights may potentially improve bone sarcoma prevention measures and broaden our understanding of the role of ionizing radiation from various sources on the development of malignant tumors. This study stresses the need to become increasingly aware of the various health risks that may be attributable to even low levels of ionizing radiation exposure.Level Of Evidence: Prognostic Level I. See Instructions to Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Although there have been several reports on the prevalence of atopic dermatitis (AD) in Japanese schoolchildren based on questionnaires, there has been no nation-wide study of the frequency of this condition diagnosed by dermatologists in regular health check-ups of schoolchildren.The objective of this work was to evaluate precisely the prevalence of AD in elementary schoolchildren in Japan based on regular health check-ups by dermatologists.In 2001/2, elementary schoolchildren: first graders (age 6–7 years) and sixth graders (age 11–12 years) were examined by dermatologists in eight prefectures of Japan (Hokkaido, Iwate, Tokyo, Gifu, Osaka, Hiroshima, Kochi and Fukuoka). In each prefecture, public elementary schools were randomly selected from urban and rural districts. We planned to examine about 700 schoolchildren in each of urban first, urban sixth, rural first and rural sixth grades from the eight areas, a total of 22 400 children (700 × 4 × 8). AD was diagnosed by the dermatologists based on the Japanese Dermatological Association criteria for the disease.The point prevalence of AD was 11·2% overall (2664 of 23 719) ranging from 7·4% (Iwate) to 15·0% (Fukuoka) in the eight areas. Seventy-four per cent, 24%, 1·6% and 0·3% of those afflicted were in the mild, moderate, severe and very severe groups, respectively. Overall, the prevalence of first graders was slightly higher than that of sixth graders (11·8% vs. 10·5%,P < 0·01). There was no apparent difference in prevalence between urban and rural districts, or between boys and girls.The prevalence of AD in Japanese elementary schoolchildren was about 10%, three-quarters of those being mildly affected. This is the first nation-wide study made of Japanese elementary schoolchildren examined by dermatologists to evaluate the frequency of AD. [ABSTRACT FROM AUTHOR]

Purpose: The well-documented increases in malignant tumours in the A-bomb survivors have recently been supplemented by reports that non-cancer diseases, including cardiovascular disease, may also have increased in incidence with increasing radiation dose. Given that low-level inflammatory responses are widely accepted as a significant risk factor for such diseases, we undertook a detailed investigation of the long-term effects of ionizing radiation on the levels of the inflammatory markers C-reactive protein (CRP) and interleukin 6 (IL-6) in A-bomb survivors. Materials and methods: Blood samples were taken from 453 participants in a long-term epidemiological cohort of A-bomb survivors. Plasma levels of CRP and IL-6 were measured using standard antibody-mediated procedures. Relationships between CRP or IL-6 levels and radiation dose were then investigated by multivariate regression analysis. Blood lymphocytes from each individual were used for immunophenotyping by flow cytometry with murine monoclonal antibodies to CD3, CD4 and CD8. Results: CRP levels were significantly increased by about 31% Gy[sup -1] of estimated A-bomb radiation (p = 0.0001). Higher CRP levels also correlated with age, male gender, body mass index and a history of myocardial infarction. After adjustments for these factors, CRP levels still appeared to have increased significantly with increasing radiation dose (about 28% increase at 1 Gy, p = 0.0002). IL-6 levels also appeared to have increased with radiation dose by 9.3% at 1 Gy (p = 0.0003) and after multiple adjustments by 9.8% at 1 Gy (p = 0.0007). The elevated CRP and IL-6 levels were associated with decreases in the percentages of CD4[sup +] helper T-cells in peripheral blood lymphocyte populations. Conclusions: Our results appear to indicate that exposure to A-bomb radiation has caused significant increases in inflammatory activity that are still demonstrable in the blood of A-bomb survivors and which may lead to increased risks of... [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the late effect on cancer mortality risk of the radiation exposure of atomic bomb survivors who comprised a study population different from that previously studied by the Radiation Effects Research Foundation (RERF). We examined survivors residing in Hiroshima Prefecture, who were followed up between 1968 and 1989 by the Research Institute for Radiation Biology and Medicine (RIRBM) at Hiroshima University. We used the doseevaluation system known as Atomic Bomb Survivors 1993 Dose (ABS93D), which was based on the Dosimetry System 1986 for the survivors registered with RERF. The dose estimation was applied in a total of 35,123 subjects. Among survivors who had been alive for 20 years after the bombing, the relative mortality risk of leukaemia at 1 Gy of organ dose was 2.37 (90% confidence interval: 1.36-3.39), which was significantly higher than the zero dose control group. Similarly, significantly higher risks were observed for all cancers except leukaemia, including cancers of the lung, colon and female breast. Comparison is made with RERF results regarding temporal changes in the relative risk. Although we observed slightly lower relative risks than RERF values for the cancer of the stomach and lung, and for all cancer except leukaemia, no marked trends for any cancer were observed in this study. Though there were some differences in population between RERF and RIRBM, no marked discrepancies were observed. [ABSTRACT FROM AUTHOR]