The purpose of this study is to investigate the effects of walking 10,000 steps per day on coronary risks including insulin resistance in Japanese. Twenty-one white-collar male workers (46.1±5.3 year-old) perform preventive lifestyle prescription. After 6 month, they showed improvements in BMI (p<0.05), VLDL (p<0.05), HDL cholesterol (p<0.001), and plasma insulin at 2 hr. post 75 g OGTT (p〈0.05). The participants increased their walk steps from 8,239±4,302 to 10,083±4,115 steps/day (p=0.09), and the increments of steps correlated with those of body mass index (r=−0.58, p<0.05), VLDL (r=−0.57, p<0.05), tryglycerides (r=−0.54, p<0.05), and blood glucose at 1 hr. post OGTT (r=−0.50, p<0.05) respectively. Especially 8 subjects with improved HOMA-R demonstrated more favorable modifications, and their gained 3,900 steps/day can meet the ACSM recommendation of physical activity. These outcomes could support a scientific aspect of anecdotal belief that walking 10,000 steps per day is effective to maintain one's optimum health.

A follow-up study was conducted until the end of 1980 on 28, 643 rural inhabitants who had undergone mass health screening between 1971 and 1978. For those who died, the causes of death were confirmed by death certificates.
The results obtained were as follows:
1) During the observation period, there were 876 death (about 3% of participants). The mortality was three times greater for males than for females and increased with age. These differences between sexes were statistically significant except the group of 29years old or under.
2) Forty-two percent of the total deaths were for cerebro-cardiovascular diseases, 32% for malignant neoplasms and 26% for others. For males, the mortality of cerebro-cardiovascular diseases was greater than those of other causes of death. On the other hand, the mortality of malignant neoplasms was higher among females.
3) The mortality rate per 1, 000 person-years of observation was 5.2 (11.8 for males and 3.2 for females). Cause- specific mortality rates were 1.7 per 1, 000 person-years for malignant neoplasms (3.1 for males and 1.2 for females); 1.2 for cerebrovascular diseases (2.8 for males and 0.7 for females), 0.9 for cardiovascular diseases (2.3 for males and 0.5 for females), 0.3 for accidents and 0.2 for pneumonia. The mortality rates of each aged-group according major causes of death were higher among males than among females except two groups of 29 years old or under and 70 years old or over of cerebral bleeding.

During the 1970's many cases of serious silicosis occurred among migrant workers doing tunnel construction.
We studied the prevalence of silicosis in the eastern part of Toyama prefecture. Questionnaires were sent to all male inhabitants aged 30 or over in the five selected areas. Eight hundred and eighty-five of respondents (41%) had worked as migrant workers. Of these, 580 men (66%) had worked on the job with exposure to dust such as tunnel construction. Of this number, 482 men were examined by chest roentgenography. Of the 482 migrant workers whose job exposed them to dust, 424 silicosis cases (88%) were found. These patients included 195 cases of category 1, 123 cases of category 2, 59 cases of category 3 and 47 cases of category 4 silicosis.
Most of the patients retired and returned to their home villages without having been given any diagnosis and medical care at their places of employment. The silicosis in 297 cases (70% of the total number of disease patients) was first detected in the course of our research.
Two thousand and seventy-seven of the respondents for questionnaire in 1977 and 1978 were followed-up until the end of 1983. For those who died, the causes and dates of death were confirmed by death certificates. The mean person-years of observation per a person was 5.9. The subjects were divided into three groups.
The mortality rate per 1, 000 person-years of migrant workers who had worked in jobs with exposure to dust was 22.3. The mortality rate was significantly higher than that of migrant workers who had not worked in jobs with exposure to dust (14.9) and those who were not migrant workers (9.1). Especially significance is the excess mortality rate of migrant workers whose jobs exposed them to dust in ages 40 to 69.
The mortality rates for pulmonary tuberculosis, pneumonia & bronchitis and pneumoconiosis among migrant workers whose jobs exposed them to dust were higher than those among non-migrant workers.

All residents aged 40 years or more in Oyabe City, Toyama Prefecture, Japan were involved in an annual medical check-up between 1987 and 1988. The cohort was followed and death certificates from cancers were confirmed prospectively. During follow-up to December 31st, 1994, 100 deaths (28 gastric, 17 lung and 55 other cancers) from cancers occurred, and these subjects were included in this study as the case group. Subjects in the control group, matched for gender and age with the cases, were selected randomly from participants whose serum samples had been stocked during annual medical check-up. The concentration of serum thiocyanate in all (79.8 μmol/l), gastric (86.7 μmol/l) and lung (90.0 μmol/l) cancer patients were significantly higher than that of relevant controls (64.3 μmol/l, 59.0 μmol/l and 61.0 μmol/l, respectively; and p<0.001, p<0.001 and p<0.05, respectively). After adjusting for BMI, blood pressure and total serum cholesterol, the results of multiple logistic regression analysis showed that the risk of all cancers (OR=3.40, 95% confidence interval (95% CI): 1.67−6.96, p<0.01), gastric cancer (OR=7.98, 95% CI: 1.91−33.34, p<0.05) and lung cancer (OR=8.83, 95% CI: 1.19−65.65, p<0.05) were elevated significantly with logarithm transformed values of serum thiocyanate increased. The present findings suggested that in epidemiological studies confirmation of smoking status with biomarkers such as serum thiocyanate may be important, although considering the small sample size, a relatively weaker risk to interested factors rather than the strong relationship between smoking and cancer was noted.
L ; Mole, unit of measurement ; lower case pea ; Serum ; Smoking

The purpose of this study is to establish the normal physiological values of glycosylated hemoglobin (HbA₁ and HbA_1C) among Japanese rural inhabitants and to evaluate its potential as a screening tool for diabetes mellitus. Six hundred and seventy-five people aged 35-64 years (210 males and 465 females) were examined. Oral glucose tolerance tests were perfomed on 135 inhabitants of them by giving a 50-gm.
Frequency distributions of HbA₁ and HbA_1C fitted approximately to the log-normal distribution.
Geometric means and standard deviations in bracket were 7.95 (1.11)% for HbA₁ in men, 8.13 (1.12)% for HbA₁ in women, 5.17 (1.10)% for HbA_1C in men and 5.16 (1.11)% for HbA_1C in women
Group average values of HbA₁ and HbA_1C tended to increase with age in both men and women except a male group aged 60 years and over. There were no significant differences between mean values of glycosylated hemoglobin in men and those in women. HbA₁ was positively correlated with age in women and negatively correlated with hemoglobin in both men and women. HbA_1C was positively correlated with age in men and women, body mass index, systolic blood pressure and serum cholesterol in women, and negatively correlated with hemoglobin in men.
In order to evaluate glycosylated hemoglobin as a screening tool for the identification of unknown persons with diabetes, we calculated the sensitivity (the extents to which the participants who were found to have a diabetic OGTT also had an abnormal glycosylated hemoglobin) and specificity (the extents to which the participants who were not diabetic had normal glycosylated hemoglobin). The sensitivities for the person aged 59 years or under using HbA₁ were 72.7-100% and the specificities 67.3-75.0 percent. Futhermore the sensitivities for the same aged person using HbA_1C were 81.8-100% and the specificities 78.8-81.3 percent. The validities for both HbA₁ and HbA_1C were higher than those for glucosuria or blood glucose. But glycosylated hemoglobin was not useful as a screening tool for the person aged 60 years and over because of the low specificity.

The purpose of this study is to investigate the prevalence of and to classify the types of silicosis patients who were working at that time as migrant workers in the eastern part of Toyama Prefecture. Migrant workers are known in Japanese as “dekasegi” This term refers to workers who migrate seasonally from their home towns to areas where work is more available.
Questionnaires were sent to all male inhabitants aged 30 or over in the selected five areas. Eighty-seven percent of the questionnaires were answered and returned. Based on the results, 482 inhabitants were selected as migrant workers with experience in jobs where they were exposed to large amount of dust. Chest roentgenography and subjective symptoms were examined in these subjects.
The results obtained were follows;
(1) Eight hundred and eighty-five of the respondents (41%) had worked as migrant workers.Of these, 580 men (66%) had worked in jobs with exposure to dust.
(2) Of the 482 migrant workers whose jobs exposed them to dust, 424 silicosis cases (88%) were found by chest roentgenographic examination. Silicosis is classified into four types according to the national Pneumoconiosis Law on the basis of chest roentgenographic findings. These patients included 195 cases of type 1, 123 cases of type 2, 59 cases of type 3 and 47 cases of type 4 silicosis.
(3) The prevalence of disease symptoms in the silicosis patients included ; cough 39%, phlegm 40%, shortness of breath 41%, palpitations 17% and wheezing in 20% of the cases. The silicosis patients showed a higher frequency of respiratory disease symptoms than those dust-exposed workers who did not evidence signs of silicosis.
(4) The silicosis patients were found in 98% of the migrant workers whose exposure to dust lasted a period of more than 20 years, 89% in men whose work was between 10 and 19 years and 76 % in men who had worked less than 10 years.
(5) The silicosis in 297 cases (70% of the total number of disease patients) was first detected during the examinations in the course of this research.

Double product (DP, heart rate × systolic blood pressure) during an incremental exercise test has been known to start to increase steeply at a workload, i. e. double product break point (DPBP), which corresponds to the blood lactate threshold. The study was to investigate the relationship between DP transition and ST segment depression in electrocardiogram during exercise. Thirty-one patients of angina pectoris of effort and 140 elderly persons performed a continuous incremental exercise test using a stationary bicycle ergometer. During the entire test, HR and blood pressure were measured every 15 seconds and an electrocardiogram was recorded continuously. DPBP was then calculated. In ten of the 31 patients, ST level depression above -0.1 mV with a typical ischemic form in lead V 5 was observed during the test. However, workload at the DPBP was significantly lower than that of the ischemic threshold on the electrocardiogram (i. e. -0.1mV of ST depression) in relation to work load (46+/-16 vs. 78+/-20 watts), HR (96+/-13 vs. 117+/-13 bpm), SBP (160+ /-20 vs. 199+/-31 mmHg) and DP (15400+/-3400 vs. 23400+/-4900 bpm × mmHg) . In elderly persons, DPBP could be determined without the ischemic ST depression in 96% of 327 tests. This study indicated that the DPBP would be an objective index of exercise intensity with lower risk for exercise prescription in cardiac patients and elderly persons.

To study diffrences in dietary factors among communities with different living environments, we carried out a survey by the Cardiac Study method in 241 people (106 men and 135 women) aged between 50 and 54 years who were selected by random sampling from a total of 37, 000 inhabitants in a small city. The city was geographically divided into town, flatland farming area, and mountainous farming area, and the results of the survey were compared among these areas.
The mean Na excretion in 24-hour specimens of urine was slightly higher in the mountainous farming area than in the other two-areas. The mean serum total cholesterol was higher in men in the town than in those in the other areas.
Factor analysis of the data for nutrient intake patterns revealed a lower fat intake in the two farming areas than in the town in the men, and a higher intake of animal foods in the town and a lower fat intake in the mountainous area in the women.
These results show that risk factors for circulatory diseases such as urinary Na excretion, serum cholesterol level, and nutrient intake patterns differ even among small areas if the living environment differs.

Hypertension is one of the major risk factors for cardiovascular disease, the prevention of which is acknowledged to be critically important. Human beings are the only animal species which consume large quantities of salt, and their consumption has increased with the advancement of civilization. Many observational and interventional epidemiologic studies have demonstrated that a high intake of salt results in elevation of blood pressure, and that a salt-reduced diet induces blood pressure reduction in patients with hypertension as well as in individuals with normal blood pressure. Reduced salt intake, blood pressure reduction, and a remarkable decrease in mortality due to stroke in Japan are important examples of this effect. A decrease in the mean blood pressure in an entire population can contribute significantly to decreased incidence of cardiovascular diseases. A population-based strategy for preventing hypertension, including a salt-reduced diet, is therefore desirable. Proposed measures include public health education by the mass media, reduced salt content in processed foods, salt reduction in foods served by schools or organizations and at restaurants, and labeling of salt content. Further studies are needed of population-wide salt reduction methods, and the effectiveness of such methods.

OBJECTIVEMaternal exposure to dioxins [polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (DFs)] during pregnancy is known to affect infant growth and neurodevelopment in humans and animals. The aim of this study was to investigate the relationship between newborn size and the concentration of dioxin isomers in breast milk and to subsequently evaluate the potential toxicity of each dioxin isomer among mothers living in sea coast areas who are at a high risk of contamination due to a high consumption of fish.

METHODSA total of 75 milk samples were obtained within 1 month of delivery from Japanese mothers living in the coastal areas of the Japan Sea. The relationships between the levels of seven dioxins and ten furan isomers in maternal breast milk, measured by high-resolution-gas chromatography/mass spectrometry, and the birth size of newborns, which is related to fetal growth, were investigated after adjustment for confounding factors.

RESULTSThe concentrations of 1,2,3,6,7,8-HxCDD (hexachlorodibenzo-p-dioxin), 2,3,4,7,8-PeCDF (pentachlorodibenzofuran), 2,3,4,6,7,8-HxCDF, and three dioxin toxic equivalent (TEQ) levels (PCDDs-TEQ, PCDFs-TEQ, and total-TEQ) in maternal breast milk were inversely correlated to newborn length even after adjustment for gestational weeks, infant sex, and maternal age and height. These isomers were abundant among the 17 isomers tested and reflected the TEQ levels. Only 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), the most toxic isomer, was negatively correlated with newborn head circumference, even after adjustment for gestational weeks, infant birth weight, and other confounding factors.

CONCLUSIONSBased on our results, fetal growth may be influenced by maternal total exposure to dioxins, but only exposure to 2,3,7,8-TCDD would appear to possibly affect fetal head size during pregnancy.