Estimating energy expenditures for daily activities has become an important issue in the promotion of individual health.
From this point of view, the variety of estimation methods and their characteristics applied in many countries were surveyed.
Then the essential bases used to estimate energy expenditures with the relative metabolic rate (RMR) method and the active energy expenditure rate (Ea) method, which were originally developed and used in Japan, were substituted for daily activities recorded by means of time study, and illustrated.
Subsequently, a newly introduced method based on heart rate was explained with its variations and problems followed by practical reports on some populations in Japan.
Methods using questionnaires or other devices were also described.

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During the past three decades, industrial expansion in Japan has been remarkable, resulting in a numerous number of chemical substances got synthesized.
Unfortunately, our living environment has concomitantly been polluted with such substances released through industrial activities and our daily lives, and health injuries have occasionally occurred in the human population. Although the critical conditions in the 1960s were overcome by the countermeasures we took, the potential for environmental pollution still remains. In the present social and economical situation, the management of environmental pollutants should be decided depending upon more quantitative and predictive evaluation of their health effects. In this paper the author tries to evaluate the relation of air pollution to chronic bronchitis, bronchial asthma and pulmonary cancer from a quantitative point of view.

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Cardiovascular disease has been the leading cause of death since 1946 in Japan. In this paper, the relationship between mortality and nutritional factors was analyzed by 12 different regions in Japan during the period 1966-1985. Data in the Reports of the National Nutritional Survey in Japan were used as the nutritional factors, and calculation was made of age-adjusted mortality from ischemic heart disease (IHD), cerebral hemorrhage (CH) and cerebral infarction (CI). The results obtained were as follows:
1. Correlation coefficients were calculated based on the average value of 20 years in each 12 different regions. Correlation coefficients between the mortality from IHD and intake of total fat and n3-polysaturated fatty acids were positively significant for both sexes. Between the mortality from CH and vegetable protein and salt, they were positively significant (p<0.01) while cholesterol was negatively significant (p<0.01). Between the mortality from CI and vegetable protein, salt and carbohydrate, they were positively significant (p<0.01).
2. Correlation coefficients beteen slopes of CH and slopes of nutrients intakes, indicated cholesterol to be negatively significant (p<0.05) for women from 1966-1970, and salt to be positively significant for men (p<0.01) and women (p<0.05) from 1974-1985. In the period 1966-1970, the correlation coefficient between slopes of IHD and those of Keys' factor was positively significant (p<0.05) for women.
3. To clarify changes in the relationship between mortality and nutrients, correlation coefficients were calculated each year from 1966 to 1985. Significant positive correlation coefficients for IHD were found with animal protein and saturated fat starting from about 1975. Salt was associated with IHD in the 1960s but not following 1970. Those of nutrients for CH and CI did not change markedly during 18 years.
4. Multiple regression analysys with intake of salt and Keys' factor indicated that the influence of salt on cardiovascular disease to decreased and that that of low serum cholesterol on CH declined. Multiple correlation coefficients with salt and Keys' factor decreased for IHD (men) and CH (women).

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An investigation on measurement of birth weight in facilities was made in the northern part of Fukuoka Prefecture from March 1989 to January 1991. The purpose of the investigation was to clarify the reliability of birth weight data in obstetric facilities. The author interviewed the manager of each facility. The data of 112 cases were analyzed.
The following results were obtained:
1) Nurses and midwives measured birth weights in many facilities, but doctors rarely did. Birth weights were obtained within an hour after birth in almost all facilities. Tare and zero-adjustment were frequently checked in many facilities, but horizontal-adjustment was not checked in about a half of the facilities.
2) The types of scales were digital scales (48.2%), dial scales (31.3%), table-top platform scales (10.7%) and bathroom scales (9.8%). It was estimated that 70.6% of the all birth weights in these facilities were obtained with digital scales. The renewals of scales in the past 5 years has resulted in the widespread use of digital scales in facilities.
3) The accuracy and precision of each scale were examined with weights of 3000g. Digital scales were superior to the other types of scales in both accuracy and precision. The legal periodical inspection for scales improved accuracy.
Procedures for measuring birth weight are not generalized among and within facilities. Digital scales have many merits for handling and reading. The spread of digital scales in facilities may decrease the degree of many kinds of errors in measurement, especially rounding errors, and improve the reliability of the data in the area.

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Based on our previous health survey among Ishigaki fishermen in 1979, this study aimed at clarifying the relations of their work histories to physical characteristics, physiological functions, blood conditions and hearing levels. Medical examination was conducted in 1987 on 118 fishermen inclusive of 33 followed-up fishermen, and in 1989 noise-level and noise-induced temporary threshold shift of hearing was measured for different fishing methods. The results were as follows; 1) Fishing history was not specifically associated with any physical characteristics. 2) High HDL cholesterol, which was observed among divers using diving apparatus, was considered to be a survival effect for divers, since HDL cholesterol is amplified by intensive muscle work. 3) Abnormalities of ECG except for a high R wave were notably observed among the divers, who once changed from unassisted diving to diving with apparatus and then to fishing lines. The main reason for switching jobs was claimed to be caisson disease, and it was suggested that diving with apparatus was related to a high risk of health hazards in the central nervous system and/or respiro-circulatory system. 4) Acoustic acuity greatly declined with aging, and which was commonly observed in groups with different work histories. By way of explanation, exposure to ship engine sounds during daily travelling was the most likely cause. It was also revealed that several hours' exposure to the engine sounds was needed to detect a temporary threshold shift of hearing before and after work.

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We studied changes of humoral immunity, such as complement pathway activity, C₃ contents and contents of immunoglobulin, in mice injected subcutaneously with BeCl₂ or CuCl₂ once a week for 12 weeks.
Mean body weights of JCL: ICR female mice were approximately 30g in control mice (control group; n=7), in mice injected with Be (Be group; n=8) and in mice injected with Cu (Cu group; n=8). Values of classical complement pathway activity (CH₅₀) were 18.8±1.4U per ml, 15.3±1.8U per ml and 16.7±1.3U per ml in the control group, Be group and Cu group, respectively. The CH₅₀ values of Be and Cu groups were significantly lower than that of the control group (P<0.01). In contrast, values of alternative complement pathway activity (ACH₅₀) and contents of C₃ were almost constant in the three groups. The immunoglobulin content in the Be group tended to increase. The activity of alanine aminotransferase in the Be group was markedly higher than that in the control group (P<0.05), and the aspartate aminotransferase activity was also high.
The CH₅₀ value of mice injected with a small amount of Be once a week over a 12-week period decreased markedly, although either the ACH₅₀ value or C₃ content was the same as in the control group. The immunoglobulin content somewhat increased in the Be group. These results suggest the possibility that immune complex is induced by Be.

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Studies were undertaken to evaluate the fundamental conditions for a low-intensity voluntary wheel running model in rats and its chronic effects on health indexes.
Male Fischer rats (SPF) 5 weeks of age were housed in individual sedentary conditions or in individual wheel-cage units which allowed free access to voluntary wheel running for 8 months. Voluntary running averaged 640±198m/day, reached a peak (965m) at the 2nd month and waned over time, reaching a plateau after the 6th month (about 400-500m). Exercising rats consumed more food (+23%), but exhibited decreased body weight gains (-9%), suggesting a remarkable lowering of fat. A lowering effect on resting blood pressure (-5%) was also recognized. In addition, preventive effects on oxygen toxicity and effective bactericidal activity of neutrophils and pulmonary alveolar macrophages (PAM) were suggested.
Although the amount of exercise in this study was the smallest of the other precedeing ones conducted with a voluntary wheel running model, many potential health benefits were recognized. Such health promoting and protecive effects by low-intensity voluntary exercise and the harmfulness of forced exrcise in rats have been reported in researches on cancer, lowering fat and hypertension. Therefore it is important to set up conditions for low-intensity voluntary running. It was also demonstrated by this study that strictly controlled environmental conditions, such as room temperature and humidity, a 12-hr light-dark cycle and prevention of infection and psychological stress to rats, as well as using male rats, which are more inactive, were important factors to establish this model.

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The instantaneous effect of the sound of a passing truck on sleep of five male students, 23 to 25 years of age, was assessed. The peak levels of noise were adjusted to 55, 60, and 65dB (A) with intervals of 18 and 13 minutes, and a frequency of one per hour. Background noise in the experimental room was Leq 42dB (A). The sleep stage of each epoch was visually judged based on the criteria of Rechtschaffen & Kales. Data for pre-exposure epochs of sleep stage 2 and rapid eye movement (REM) were collected and 18 epochs, including two under noise exposure, were evaluated. Three sets of polygraphic data were sampled as controls from 10 minutes after 65dB (A) exposure to the next exposure.
Compared with the control, the percentage of stage 2 to shallower stages (stage 1, waking, or movement time (MT)) was significantly increased by exposure to 55, 60, and 65dB (A). The change lasted for one minute with exposure to 55dB (A), and 2 to 3 minutes with 60 and 65dB (A). A decrease in the percentage of stage 2 to deeper stages was observed at 2 to 4 minutes after exposure to 60 and 65dB (A). The percentage of stage 2 to MT increased at 60 and 65dB (A). The percentage of stage REM to other stages increased with the exposure to 60 or 65dB (A) within 4 minutes.
The threshold of instantaneous change of stage 2 to shallower stages due to the sound of a passing truck was at the peak level at less than 55dB (A), and that of stage REM to other stages at 55 to 60dB (A).

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To clarify which sites of the central nervous system are influenced by acute administration of alcohol at an early stage, auditory event-related potentials (ERP) using a target-selection paradigm were measured in 13 healthy volunteers. In the recorded waveforms of ERPs, the N100, P165, N200 and P300 latencies for the target tone and the N100 and P200 latencies for the non-target tone were determined in each subject before and 1- and 2-hr after ingestion of 200ml of alcohol (containing 25% ethanol) or of 200ml of water, for a total of six times on two different days. The P300 latency was significantly prolonged at 1- and 2-hr after alcohol ingestion; and, the N200 latency was significantly prolonged at 2-hr after alcohol ingestion. The 2-hr alteration in the P300 latency after alcohol ingestion was positively correlated with the ethanol dose per body weight. These data suggest that ethanol, in proportion to its dose, affects cognitive function estimated by the P300 latency earlier than other lower central nervous system functions. Evaluating subclinical effects on central nervous function, using the ERPs, of environmental neurotoxins such as organic solvents, researchers should pay particular attention not only to the degree of the drinking habit but also to the interval between the measurement and alcohol intake.

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The effect of copper sulfate (CuSO₄) on cultured human vascular endothelial (HVE) cells and cultured human fibroblasts (HAIN-55) was investigated. HVE cells were collected from umbilical veins by enzymatic digestion with collagenase. The viability, subsequent growth and DNA synthesis of both cell types were inhibited concentration-dependently by the addition of copper. The cytotoxic effect of copper on the morphology of these cells was also concentration-dependent. However, the cytotoxic effect of copper on the viability, subsequent growth and DNA synthesis was greater in HVE cells than in HAIN-55 cells. These results suggest that HVE cells are more susceptible to concentration-dependent copper cytotoxicity than HAIN-55 cells are, and that copper could induce vascular endothelial injury, which may be involved in the pathogenesis of cardiovascular disease.

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