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Background and Objectives: To investigate the prolonged effects of a 12-month exercise-plus-diet intervention in Japanese adults at risk of impaired glucose or lipid metabolism., Methods and Study Design: A total of 180 participants were randomly divided into an intervention group (n=94), and a control group (n=86). An exercise-plus- diet intervention was conducted on the intervention group for 12 months. The effects were evaluated by questionnaire, physical examinations, and blood tests at baseline, 3 months, 12 months (the end of intervention), and 24 months (one year after the end of intervention). The control group took only the same examinations as the intervention group., Results: At the end of the 12-month intervention, body weight, waist circumference, fasting glucose, HbA1c, triglycerides, and LDL-cholesterol were improved in the intervention group compared to the control group (all p<0.05). One year after the end of the intervention, body weight, waist circumference, fasting glucose, triglycerides, and LDL-cholesterol were still decreased in the intervention group compared to the control group (all p<0.05), especially among non-overweight participants. Among overweight persons, only body weight in the intervention group was lower than the control group. The personal behaviours of physical activity and diet in the intervention group were also improved., Conclusions: The 12-month exercise-plus-diet programs were found to be effective in improving glucose and lipid metabolism, as well as personal behaviour one year after completion of the intervention.

To investigate the level of walking activity among residents of the Tohoku district in northern Japan, where no widespread public transport system has been developed, winter is severe. The participants were 50 town hall employees with an average age of 43.6+/-10.8 (SD) years. The walking activity of each participant was assessed using a pedometer for one week in summer and one week in winter. The participants' lifestyles, including their commuting methods, were assessed using a questionnaire. Forty-six participants (92%) usually commute to work by private car. The average numbers of steps/day on workdays and holidays were, in summer, 6,560+/-2,600 and 7,016+/-4,679, respectively, and, in winter, 5,236+/-2,253 and 4,770+/-3,039; these numbers were somewhat lower than those recorded in previous reports. We observed a significant reduction in walking during winter (F=19.016, p=0.0001), but no significant differences between workdays and holidays (F=0.001, p=0.966). A significant correlation between BMI and steps/day (r=-0.420, p<0.01) was obtained on workdays in winter. The unexpectedly low level of these participants' physical activity, especially in winter, is probably due to the fact that most of them commute by private car, which is likely a cause of the high incidence of obesity in this district. In addition, a seasonal effect should also be considered when physical activity is assessed, especially in cold climates.

Bioelectrical impedance analysis (BIA) is commonly used to measure the percentage of body fat (%BF), but its accuracy is controversial. In addition, the equations are specific to the group for which they were established. As far as we know, there is no study examining the accuracy of BIA in Japanese middle-aged and older people. We compared %BF assessed using BIA with that of dual-energy X-ray absorptiometry (DEXA) in 102 female and 51 male local residents aged 40 to 78 y. Simple correlation coefficients were 0.79 for females and 0.69 for males, which are statistically significant (p<0.001). However, BIA tended to overestimate %BF in the lower BF group and underestimate it in the BF higher group, and only 45.1% for female and 47.1% for male subjects were measured accurately, i.e., within 10% of the measurement by DEXA. This result suggests that this model of BIA is an alternative for estimating %BF in Japanese middle-aged and older people as well as when subjects are within a normal body fat range, but greater accuracy is needed for lean and overweight subjects.

Background: Many commercially available sports drinks contain 5-6% carbohydrates, some of which is fructose. However, a number of studies of abdominal complaints have indicated fructose malabsorption. In the present study, we examined colonic fermentation of a fructose-containing sports drink., Methods: Colonic fermentation was determined in normal subjects by measuring breath hydrogen after ingestion of 350 ml sports drink, cow s milk, or green tea with a 200 g rice ball., Results: The incidence of colonic fermentation after ingesting sports drink, milk, and green tea was five (62.5%), six (75%), and none (0%), respectively in eight subjects. Peak increases (ppm) after ingestion of sports drink and milk varied from 0 to 6 (3.1 +/- 0.9) and 0 to 12 (6.5 +/- 1.7), respectively., Conclusions: Although the increase of breath hydrogen was not associated with abdominal discomfort and its effect on exercise is still unclear, we suggest avoiding a large ingestion of fructose-containing sports drink before and during exercise.

The 28-year follow-up of a Japanese cohort, having collected vast amounts of data collected on total serum cholesterol (TC), provided an exceptional opportunity to examine TC temporal trends. The longitudinal statistical method of growth-curve analysis was used to elucidate the age-related changes in TC levels and to characterize these trends in relation to sex, birth cohort, time period, place of residence, and body mass index (BMI). Japanese TC levels at initial examination were remarkably lower than those in western countries. During the study period from 1958 to 1986, TC levels increased dramatically with age in both sexes. The slope of the cholesterol growth curve was steeper for women than for men, with the difference growing larger after age 40 years. Drastic changes in Japanese behavior and lifestyle, especially westernization of the diet, are thought to have affected the TC values as time-period effects. As a result of this temporal change, which affected different cohorts at different ages, TC values were higher in members of the younger cohort. The increase of the TC values as time-period effects were larger in earlier period than in later period. These time-period effects appeared to be almost similar in men and women. The TC growth curves also varied by city of residence. Subjects in urban areas had higher TC values than subjects in rural areas. Changes associated with BMI from 1958 to 1986 were only partially responsible for the increased steepness of the TC growth curve.

Although the close relation between blood pressure and physical development in adolescence has been established in cross-sectional and comparative cross-sectional studies, the entire trend of systolic blood pressure (SBP) during adolescence has not been elucidated in conjunction with physical development in a longitudinal study. Blood pressure (mmHg), body weight (kg), and body height (m) were measured annually for 418 subjects in Hiroshima and Nagasaki, Japan, from age 10 (1955 or 1956) through 18 years (1963 or 1964). The Gompertz growth model was used to determine the velocity of weight increase (VEL) during that age period. The relations between SBP from age 10 to 18 and VEL, weight, height, body mass index (BMI; weight/height2, kg/m2), and the age at which the measurements were made were investigated individually using random-coefficient growth-curve analysis. The SBP trend for the 10- to 18-year age period could be shown by the following prediction equations: for the 163 Hiroshima males, SBP = 82.38 + 0.89 VEL at age 1.15 years prior to the current examination (VEL (age - 1.15)) + 1.40 BMI; for the 57 Nagasaki males, SBP = 92.70 + 1.07 VEL (age - 1.15) + 0.79 BMI; for the 148 Hiroshima females, SBP = 104.88 + 1.63 VEL (age - 1.15) + 0.05 BMI; for the 50 Nagasaki females, SBP = 113.62 + 1.67 VEL (age - 1.15) - 0.59 BMI. VEL 1.15 years prior to the current examination was significantly and positively related to SBP in each city by sex group (p < 0.01), and current BMI was significantly related to SBP for males in Hiroshima (p < 0.01) and nearly so in Nagasaki (p = 0.06), but not for females in either city (p = 0.84 and 0.13, respectively). Because the plot of VEL was a convex curve, SBP peaked approximately 1-2 years after the peak in VEL and then decreased in both sexes. The entire SBP trend during adolescence can be expressed as an equation of VEL and BMI in males and of VEL in females. SBP does not increase linearly with age.

Adult T-cell leukemia (ATL), induced by human T- lymphotropic virus type-I (HTLV-I), is endemic in Nagasaki, Japan. To investigate the effects of atomic-bomb radiation on development of this specific type of leukemia, 6182 individuals in the Radiation Effects Research Foundation (RERF) Adult Health Study sample in Hiroshima and Nagasaki were examined for positive rate of HTLV-I antibody. Several lymphocyte parameters were also studied for 70 antibody- positive subjects in Nagasaki. The HTLV-I antibody-positive rate was higher in Nagasaki (6.36%) than in Hiroshima (0.79%) and significantly increased with increasing age, but no association was observed with radiation dose. Whether relationship existed between antibody titer levels and radiation dose among antibody-positive subjects was not The frequency of abnormal lymphocytes tended to be higher in antibody-positive subjects than in antibody-negative subjects, and higher in females than in males regardless of radiation dose. The lymphocyte count was lower in antibody-positive subjects than in antibody-negative subjects and lower in female than in male subjects. No evidence was found to suggest that atomic-bomb radiation plays an important role in HTLV-I infection.

Objective: To elucidate the current thyroid disease status for the Nagasaki Adult Health Study cohort of the Radiation Effects Research Foundation., Design: Survey study., Setting: Nagasaki, Japan., Participants: Cohort members of the Nagasaki Adult Health Study who received biennial health examinations from October 1984 to April 1987 (n = 2856). A total of 2587 subjects remained after exclusion of persons exposed in Hiroshima or in utero and those who were not in Nagasaki at the time of the bombing. Thyroid radiation dose by the dosimetry system established in 1986 was available for 1978 of the 2587 subjects., Main Outcome Measures: Thyroid diseases were diagnosed using uniform procedures including ultrasonic scanning. The relationship of the prevalence of each thyroid disease with thyroid radiation dose, sex, and age was analyzed using logistic models., Results: A significant dose-response relationship was observed for solid nodules, which include cancer, adenoma, adenomatous goiter, and nodules without histological diagnosis, and for antibody-positive spontaneous hypothyroidism (autoimmune hypothyroidism) but not for other diseases. The prevalence of solid nodules showed a monotonic dose-response relationship, yet that of autoimmune hypothyroidism displayed a concave dose-response relationship reaching a maximum (+/- SE) level of 0.7 +/- 0.2 Sv., Conclusions: The present study confirmed the results of previous studies by showing a significant increase in solid nodules with dose to the thyroid and demonstrated for the first time a significant increase in autoimmune disease among atomic bomb survivors. A concave dose-response relationship indicates the necessity for further studies on the effects of relatively low doses of radiation on thyroid disease.

A fixed population of about 120,000 subjects was selected from those A-bomb survivors and unexposed controls for the purpose of follow-up studies on their late health effects. One hundred twelve cases of thyroid cancer were found in the study period between 1958 to 1979. The relative risk increased with thyroid dose: the excess relative risk per Gray was 1.1. The prevalence of thyroid diseases was evaluated in 2,587 subjects in Nagasaki: one or more diagnoses for thyroid diseases were made in 447.

To examine the potential causes of increased levels of calcium in serum with increasing dose of atomic bomb radiation, which was obtained from the previous preliminary analysis, levels of parathyroid hormone (PTH) and calcitonin in serum were examined among 1459 subjects in Hiroshima and Nagasaki. A significant effect of radiation on levels of calcium, PTH and calcitonin in serum was found, even after patients with hyperparathyroidism were excluded. The level of calcium in serum increased with radiation dose; this can be explained partly by the increase in the level of PTH with radiation dose. However, the dose effect on calcium remained even after adjustment for PTH, calcitonin and confounding factors such as renal function, serum albumin level and medication. Parathyroid hormone increased initially by 6.8% per gray, but the dose response leveled off after about 1 Gy. The level of calcitonin increased with radiation dose, probably in part due to feedback mechanisms stimulated by the increase in calcium. However, after adjustment for the level of calcium, the increase in the level of calcitonin with dose was still found. Although the etiological mechanisms of the effect of radiation on serum levels of calcium, PTH and calcitonin are unclear, radiation exposure may affect secretion of PTH and calcitonin and regulation of calcium a long time after atomic bomb exposure.

The purpose of this study was to determine if exposure to atomic bomb radiation affects immune responsiveness, such as the occurrence of autoantibodies and levels of immunoglobulins. Rheumatoid factor, antinuclear antibody, antithyroglobulin antibody, anti-thyroid-microsomal antibody and immunoglobulin levels (IgG, IgM, IgA and IgE) were measured among 2,061 individuals exposed to atomic bomb radiation in Hiroshima and Nagasaki whose estimated doses ranged from 0 to 5.6 Gy. The prevalence and titers of rheumatoid factor were found to be increased in the individuals exposed to higher radiation doses. The IgA level in females and the IgM level in both sexes increased as radiation dose increased, although the effects of radiation exposure were not large. No effect of radiation was found on the prevalence of antinuclear antibody, antithyroglobulin antibody and anti-thyroid-microsomal antibody or on the levels of IgG and IgE.

Using the longitudinal data of the Adult Health Study (AHS) cohort collected during 1958-1986, we examined for the first time the relationship between exposure to ionizing radiation and the incidence of 19 nonmalignant disorders in the A-bomb survivors. Affected individuals were ascertained through the three-digit codes of the International Classification of Diseases which are encoded in the AHS database subsequent to diagnoses made on the basis of general laboratory tests, physical examinations, and history-taking conducted during biennial AHS examinations. The disease onset time was estimated using the mid-point between the AHS examination data when the disease was initially reported and the previously attended disease-free examination date. Dosimetry System 86 organ doses judged to be most appropriate were used. Tests of dose effects were performed assuming a linear relative risk model with stratified background incidence. For the entire study period, significant excess risk was detected for uterine myoma (P < 0.001), chronic liver disease and cirrhosis (P = 0.006), and thyroid disease (P < 0.0001), defined broadly as the presence of one or more of certain noncancerous thyroid conditions. The incidence of myocardial infarction was shown to be increased (P = 0.03) in later years (1968-1986) among the younger heavily exposed AHS subjects, confirming the results of the recent Life Span Study (LSS) noncancer mortality report on coronary heart disease. The findings for uterine myoma may serve as additional evidence indicating benign tumor growth as a possible consequence of radiation exposure. Our results indicating the involvement of radiation in the development of liver diseases are consistent with the report of increased mortality from liver cirrhosis with radiation dose in the LSS cohort. An effect of age at exposure was detected for nonmalignant thyroid disease (P = 0.02), with an increased risk for those exposed who were under 20 years of age, but not for older survivors. Thus the AHS data suggest that thyroid glands in the young are more radiosensitive not only to the development of malignancies, but also to the development of nonmalignant disorders as well. The findings hold independently of the dose effects observed for thyroid cancer. This study also shows that for the period 1958-1986 new occurrences of lens opacity are not increased with radiation dose (P = 0.39) in the AHS subjects.

To determine the effect of exposure to atomic bomb radiation on the occurrence of hyperparathyroidism, the prevalence was determined among a population of 3,948 atomic bomb survivors and their controls in Hiroshima. The diagnosis of hyperparathyroidism was based upon histopathological findings or the presence of consistent hypercalcemia and elevated levels of serum parathyroid hormone. Primary hyperparathyroidism was diagnosed in 19 persons (3 males, 16 females). Females had approximately a threefold higher overall prevalence of hyperparathyroidism than males (P less than 0.05). The prevalence rates of hyperparathyroidism increased with radiation dose (chi2(1) = 12, P less than 0.001) after adjusting for sex and age at the time of the bombing. The estimated relative risk was 4.1 at 1 Gy (95% confidence limits 1.7 to 14). There was some evidence that the effect of radiation was greater for individuals who were younger at the time of the bombing. In conclusion, exposure to atomic bomb radiation affected the occurrence of hyperparathyroidism, suggesting that doses of radiation lower than those used in radiotherapy may also induce this disorder.

An examination of registered cases of parathyroid tumor in Hiroshima Prefecture between 1974 and 1987 revealed 23 cases. An epidemiological study showed that the incidence of parathyroid tumors in Hiroshima Prefecture was significantly higher in the total exposed, especially among the proximally exposed (within 2,000 m from the hypocenter), than in the control nonexposed group (P less than 0.001). A similar trend was seen for parathyroid tumor associated with primary hyperparathyroidism.

Parathyroid tumors in A-bomb survivors in Hiroshima have been studied. Thirteen cases of parathyroid tumor were confirmed from 4,136 autopsy cases between 1961 to 1977, and an elevated incidence of tumor with increase of dose (T65D) was demonstrated (P less than 0.01). A high proportion of 42.9%, 6 out of 14 parathyroid tumors extirpated at Hiroshima University Hospital between 1956 and 1988, were atomic bomb survivors exposed within 4.1 km from the hypocenter. From an epidemiological study using 23 parathyroid tumor cases detected in Hiroshima Prefecture between 1974 and 1987, an elevated incidence of parathyroid tumors with increase of dose (proximally exposed, other exposed and control nonexposed) was demonstrated (P less than 0.001).

With 612 cases of malignant thyroid tumor, the follow-up observations were conducted from 7 to 11 years after initial examination, and 512 cases were follow up. It was found that 46 cases died of the primary cancer, while 13 died of other causes. The prognosis proved to be favorable with adenocarcinoma but with anaplastic carcinoma or squamous cell carcinoma the disease proved to be ultimately fatal. The survival rates 5 and 10 years after diagnosis were 97.4% and 95.8% for papillary adenocarcinoma, 95.6% and 92.5% for follicular adenocarcinoma, 7.7% and 7.7% for anaplastic carcinoma, 0% for squamous cell carcinoma, and 66.9% and 66.9% for malignant lymphoma. As to the causes of death, the obstruction due to the neck tumor ranks first, indicating that respiratory deaths are numerous. However, as there are histologically many deaths due to the transformation from adenocarcinoma to squamous cell carcinoma or anaplastic carcinoma, it is desirable to perform radical surgery at an early stage.