Search PubMed⌕ Search

Biomedical subjects

M Futatsuka

Publications and source records attributed to M Futatsuka.

At least 37 records · Page 2Linked to original sources
PubMed1995

Adaptation of the resettled Kenyah Dayak villagers to riverine environment in east Kalimantan: a preliminary report.

The Kenyah Dayak in East Kalimantan (Indonesia), who migrated from their mountainous homeland to a riverine village in the 1940s, have subsisted on slash-and-burn rice cultivation. To cope with rapidly increasing population, the villagers have not changed their farming practice to increase land productivity but instead have exploited fields in remote riverbanks, using motorized canoes.

Agriculture↗
PubMed1995

[Mercury].

Explore the source record for details and available documents.

Humans↗
PubMed1995

Hand-arm vibration in tropical rain forestry workers.

Working conditions and health hazards including vibration syndrome related to forestry work using chain-saws were studied in Papua New Guinea and Indonesia. The subjects comprised 291 workers including 97 chain-saw operators. The health examination consisted of peripheral circulatory and sensory tests in the upper extremities. The vibration spectrum measured at the handle of the chain-saw indicated that these acceleration levels would lead to a moderately high risk of hand-arm vibration syndrome (HAVS). The peripheral circulatory function tests revealed dysfunction after more than five years vibration exposure. However, in general, the results of the function tests and subjective complaints showed fewer health problems compared to those of Japanese forestry workers. The reason of such differences of vibration effects seem to be the following: (1) warmer climate (more than 25 degrees C throughout the year), (2) young workers and short work experience. (3) short time vibration exposures on working days in the natural forests, (4) seasonal changes in logging work (5) healthy workers effects. Thus, we found no clear evidence that the workers of our study suffered from HAVS. A principal component analysis was applied. The factor score of the components of the reactive dynamics of peripheral circulation differed significantly after more than five years' exposure. On the other hand, we cannot deny the possibility that subclinical dysfunction of peripheral circulation may be caused by chain-saw operation in the tropics in future. Further investigations on the HAVS among forestry workers in the tropic environment are needed.

Adult↗
PubMed1994

Vibration exposure and prevention in Japan.

Working conditions of vibration exposure have generally improved, but many difficult problems must be solved such as (1) hygienic improvements in a variety of vibrating tools; (2) improving working conditions, for example, by limiting the time of operation in spite of economic difficulties such as those faced by those who work on a piece rate basis; (3) gathering more complete information about the risk population because of the large number of self-employed in informal employment sectors; and (4) finding work places after rehabilitation for patients, particularly in mountainous rural areas or in small scale industries. Historical observation of vibration and preventive measures in Japanese national forests was presented on the basis of the results of a retrospective cohort study in Kyushu, Japan. Prevalence rate of VWF remarkably changed from 58.4% in the groups that began to operate chain saws in 1960 to only a few cases in the groups who started the operation after 1971. When we compare the relationships between the results of long term cohort study and the consequences of preventive measures of vibration syndrome, the most important factor is the decrease of vibration exposure (improvement in chain saws plus the time restriction system). The comprehensive prevention system used in Japanese national forests consists of the following: (1) Health care system; (2) Work regulation system; (3) System for improving mechanized tools; (4) Warming system to protect against cold conditions; and (5) Education and training system.

Humans↗
PubMed1994

Correlations among examination findings, subjective symptoms and classification of stages in vibration syndrome.

From data collected in 1966, 1973, 1986 and 1989, we analyzed the correlations among examination findings, subjective symptoms, stages in the disorder of vibration syndrome and vibration exposure. As vibration syndrome progressed and vibration exposure accumulated, abnormality of examination findings, the prevalence of vibration induced white finger (VWF), numbness (N) and other subjective symptoms increased. Abnormality of examination findings and prevalence of subjective symptoms in the VWF(+) N(+) group were greatly different from those in the VWF(-) N(-) group. Both findings and symptoms showed closer correlations with VWF(+) than with N(+). Stages in the disorder traced the progression from VWF(-)N(-) to VWF(-)N(+), then to VWF(+)N(+/-), and finally to VWF(+/++)N(+/++). Pathophysiologically, it seems that VWF(+) and N(+) relayed many more cold and pain signals from the hand to the central nervous system. Such signals may activate autonomic nervous activity. In the recovery, subjective symptoms correlated more closely with N(+) than with VWF(+). This is because VWF involves the autonomic nervous system's hyperactivity and hypersensitivity to cold, both of which subside gradually in the recovery; N, however, involves pathological changes in nerve tissue which are irreversible.

Adult↗
PubMed1993

Comparative study of modification and degradation of neurofilament proteins in rats subchronically treated with allyl chloride, acrylamide, or 2,5-hexanedione.

Allyl chloride (ALL), acrylamide (ACR), and 2,5-hexanedione (2,5-HD) are all industrial neurotoxicants and known to produce accumulation of neurofilament (NF) proteins in both the central and peripheral nervous systems. To clarify whether any common mechanisms underlie these neurofilamentous axonopathies, the ability of ALL, ACR, and 2,5-HD to cross-link the NFs and the effects on NF degradation by Ca(2+)-activated neural protease were investigated in spinal cords from rats subchronically treated with these chemicals. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by immunoblot analysis revealed the appearance of high-molecular-weight species of NF triplets immunoreactive to each anti-68K, anti-160K, and anti-200K NF antibody in the 2,5-HD-treated rats, whereas it was not found in those treated with ALL or ACR. A time course study on the degradation of NF proteins conducted by the co-incubation with Ca2+ showed degradation resistance in all three NF subunits from animals treated with 2,5-HD, while no significant alterations in the rate of NF degradation were observed in the ALL- or ACR-treated group. The present results suggest that neurofilament-filled axonopathy induced by ALL or ACR and axonopathy induced by 2,5-HD may not share a common mechanism, though the initial step for the pathogenesis of this chemically induced neurotoxicity is not fully understood at present.

Acrylamide↗
PubMed1993

HTLV-I, HIV-I, and hepatitis B and C viruses in Western Province, Papua New Guinea: a serological survey.

Seven hundred and twenty-three serum samples from individuals in 13 Gidra-speaking villages in Western Province, Papua New Guinea were tested for evidence of infection with human T-lymphotropic virus type I (HTLV-I), human immunodeficiency virus type I (HIV-I), hepatitis B virus (HBV) and hepatitis C virus (HCV). No samples were positive for antibodies to HIV-I. Antibodies to HTLV-I were found in 13 samples (1.8%), HBV surface antigens (HBsAg) were found in 86 samples (11.9%), and antibodies to HCV were found in 30 samples (4.1%). Six (46.2%) of 13 HTLV-I positive samples were positive for HCV or HBsAg. The seropositive rate varied in different villages and the incidence of HTLV-I and HCV was higher in coastal and riverine areas than inland.

Female↗
PubMed1993

[Difference by sex and age of mercury concentration in red blood cells].

The mercury concentration in red blood cells (RBCs) is one of the most useful indicators for people exposed to methylmercury. Sex- and age-related differences in mercury concentrations in red blood cells were studied by considering fish consumption in 1,253 adults (511 males and 742 females) participating in a mass health examination conducted in a town of Kumamoto Prefecture in 1989. The results were as follows: 1. The mercury concentrations in RBCs showed lognormal distributions for both sexes with a higher mode in males than in females. The geometric mean of the mercury concentrations in the RBCs was 28.5 ng/g (ranging from 5.6 to 71.0 ng/g) for males and 20.4 ng/g (ranging from 3.7 to 70.4 ng/g) for females and was significantly higher in males than in females. The mercury concentration in RBCs decreased with aging for both sexes. 2. The mercury concentrations in RBCs significantly increased with the amount of fish consumption for both sexes. The mercury concentrations in RBCs were significantly higher in drinkers than in non-drinkers for males and the concentrations increased significantly with body weight for females. 3. The mercury concentrations in RBCs were higher in males than in females and decreased with aging for both sexes under conditions of a constant level of fish consumption. 4. In couples who consumed same amount of fish, the mercury concentrations in RBCs were significantly higher in husbands than in wives. These results suggest that the mercury concentrations in RBCs are higher in males than in females and decreases with aging under a constant level of fish consumption.

Adult↗
PubMed1992

An epidemiological study with risk analysis of liver diseases in the general population living in a methyl mercury polluted area.

STUDY OBJECTIVE: The aim was to determine the actual prevalence of liver disease and to investigate the contribution of various risk factors to liver disease among the population in a methyl mercury polluted area. DESIGN: The study was a population based cross sectional mass screening survey. A case-control study was designed to estimate the role of various risk factors for liver diseases. SETTING: The study was confined to a small rural town 10 km north of Minamata City. SUBJECTS: 1406 persons aged 50 to 69 years were examined (78.3% of the total population of this age in the locality). MEASUREMENTS AND MAIN RESULTS: Measurements of liver disease were made on the basis of haematological, physical, and ultrasonographic examinations. Data on liver risk factors were collected by questionnaire, and by measurement of body height, weight (obesity), and hepatitis B surface antigen (HBsAg). The prevalence rate of liver tumour was 0.5% in males, liver cirrhosis was found in 0.5% of males and 0.1% of females, and hepatitis was seen in 5.4% of males and 1.0% of females. Frequency rates of risk factors for liver disease among subjects with obesity were significantly higher in the female patient group, and the frequency rate among subjects with alcoholic drinking habits was significantly higher in the male patient group. The odds ratio of past history of blood transfusion showed the highest value among other related factors (7.73) and the attributable risk for this was very high (87.1%); HBsAg was next in rank (odds ratio 3.04; attributable risk 67.1%). CONCLUSIONS: The prevalence of liver disease in this methyl mercury polluted area was not increased, contrary to what was expected based on the standard mortality ratios. The main risk factors for liver disease in this area appear to be alcoholic drinking habits and a history of blood transfusion.

Aged↗
PubMed1992

Occupational asthma induced by the fungicide tetrachloroisophthalonitrile.

A 48 year old male farmer had recurrent episodes of dyspnoea, shortness of breath, and wheezing after being in his plastic greenhouse when the fungicide tetrachloroisophthalonitrile had been sprayed. A bronchial provocation test with a control challenge and a patch skin test confirmed that his asthma was induced by tetrachloroisophthalonitrile.

Agricultural Workers' Diseases↗
PubMed1992

[A cross-sectional study of lipid peroxide levels (plasma TBA levels) in a mass health examination].

Differences in plasma thiobarbituric acid (TBA) levels were studied by sex and age in 1,178 adults (471 males and 707 females) participating in a mass health examination conducted in a town of Kumamoto Prefecture in 1989. The relationships between plasma TBA levels and obesity, the consumption of cigarettes, alcohol, and fish, and various indices for health status derived from the data of physiological examinations were analyzed in age-groups 40-59 and 60-79 for both sexes. The prevalence of abnormal physiological findings by plasma TBA levels were further investigated. The results were as follows; 1. The highest plasma TBA levels for males were observed in the group aged 40-49, with levels gradually decreasing with age thereafter. The plasma TBA levels for females increased with age and the highest levels were obtained at age 60-69. The plasma TBA levels for males were significantly higher than for females at aged 40-49. 2. Plasma TBA levels for both sexes increased with obesity and the amount of fish consumed. 3. Plasma TBA levels in all examined groups had significant and strong positive correlations with serum total cholesterol levels and atherogenic indices, and had significant positive correlations with serum calcium and gamma-GTP levels. 4. A stepwise multiple regression analysis showed that plasma TBA levels for males were associated with serum total cholesterol, gamma-GTP, fish consumption and serum HDL-cholesterol in that order. The levels for female were associated with serum total cholesterol, body mass index, serum HDL-cholesterol and serum calcium in that order. The relationship with serum HDL-cholesterol was a negative correlation. 5. Prevalence of abnormal values of serum total cholesterol, atherogenic index and body mass index were significantly higher in the high-plasma TBA level group than in the group with median-plasma TBA level. These results suggest that plasma TBA levels may be useful as an index of undesirable lipid metabolism. Further studies should be performed to establish the significance of the relation of plasma TBA levels to fish consumption.

Adult↗
PubMed1991

Present mercury levels in red blood cells of nearby inhabitants about 30 years after the outbreak of Minamata disease.

Samples of red blood cells (RBCs) from 1178 inhabitants, consisting of 546 males and 795 females (over 40 years old), of a coastal town near Minamata City were analyzed for total mercury. The mercury concentrations in the RBCs showed lognormal distributions for both sexes with higher values in males than in females. The geometric mean of the mercury concentrations in the RBCs was 27.5 ng/g (ranging from 8.0 to 69.1 ng/g) for males and 20.4 ng/g (ranging from 7.0 to 63.7 ng/g) for females. The mercury concentrations in the RBCs decreased with advancing age. A significant regression between the geometric mean of the mercury concentrations in the RBCs and age was obtained for both sexes. The mercury concentrations in the RBCs from male inhabitants of the coastland area were significantly higher than those from male inhabitants of the inland area. In terms of occupation, the highest mercury concentrations were observed in the RBCs from fisherman. No significant difference in the present mercury concentrations in the RBCs was observed between the cases with Minamata disease and the controls.

Aged↗
PubMed1991

[Neurotoxicity of allyl chloride in rats. Dose-effect relationship following long-term exposure].

To elucidate the dose-effect relationship of neurotoxicity of allyl chloride (AC) in Donryu rats, 5 animals each were exposed to 10, 50 and 100 ppm AC for 8 h/d and 5 d/wk for a period of 34 wk. Nerve conduction velocities of the tail nerve in rats were determined before and after 4, 8, 12, 16, 22, 28 and 34 wk of exposure, and the width of landing foot-spread after 8, 12, 16, 28 and 34 wk. Animals subjected to 100 ppm AC showed significant (p less than 0.01) reduction of motor and sensory nerve conduction velocities and nerve action potentials (NAP) after 28 wk when clinical signs of neuropathy were observed, i.e., weakness of hindlimbs and significantly (p less than 0.01) extended landing foot-spreads. Motor distal latency was retarded in rats exposed to 100 ppm AC at the last period of exposure. In rats exposed to 50 and 100 ppm AC, no remarkable electrophysiological findings or abnormal clinical signs were observed except for depressed amplitude of NAP in 50 ppm-exposed rats when compared with those exposed to 10 ppm.

Action Potentials↗
PubMed1991

A preliminary study on the function tests of the vibration syndrome in tropical rain forest workers.

Working situations and health hazards directly related to the work of the tropical rain forest workers were studied in Papua New Guinea. The results of the function tests of the vibration syndrome were reported in the preliminary step of this study. Among 61 workers including 16 chain saw operators no clear evidence was found that was related to the health effects of hand-arm vibration, but a possibility existed of an occurrence of subclinical dysfunction of peripheral circulation and peripheral neuropathies. The principal component analysis suggests that the reactiveness of peripheral circulation significantly reflects the duration of the chain saw operation.

Adult↗
PubMed1990

Validity of function tests on the upper extremities in establishing a prognosis in vibration syndrome.

The validity of function tests on the upper extremities as prognostic tools in vibration syndrome was evaluated over a sequence of observation periods. The subjects examined were 672 forest workers using chain saws who had had some complaints and who had shown abnormal findings in the function tests. The function tests consisted of peripheral circulatory and sensory tests, including cold provocation and motor tests of functional capacity in the upper extremities. From the results of testing, 23 variables were selected and examined by multivariate analysis. The four principal components were extracted by principal component analysis, and the factor score of the peripheral circulatory disturbances component was found to be highly correlated with the severity of VWF (Vibration-induced White Finger). The course of VWF and the nail compression test had high standard regression coefficients with the severity of vibration syndrome. The course of finger numbness, pinching power, pain threshold, skin temperature and X-ray findings in the elbow joints had high discriminant function values for the evaluation of the severity of vibration syndrome.

Discriminant Analysis↗
PubMed1990

[An epidemiological study on relationship between life style and colorectal cancer].

In Kumamoto prefecture, 2,359 cases were diagnosed as colorectal cancer and operated in 5 years from 1983 to 1987. Their records were analysed to determine the annual incidences in the cecum, ascending, transverse, descending, sigmoid colon and rectum. The female age-adjusted mortality from cancer of the cecum and ascending colon was slightly surpassed that of the male's. While the incidences of colonic and rectal cancer were 21.0 per 100,000 in 1983, they have increased to 26.0 per 100,000 in 1987. As for the crude mortality, it was 11.5 per 100,000 in 1983 and 13.5 per 100,000 in 1987 respectively. Increasing of the incidence was greatest in people over 50 years of age.

Adult↗
PubMed1990

Hand-arm vibration, noise, temperature and static load--an experimental study of peripheral circulation while operating chain-saws.

From the viewpoint of elucidating the etiological mechanism of vibration-induced white finger (VWF), a model experiment was designed using a chain-saw under laboratory conditions. Finger skin temperature and finger blood flow were measured simultaneously as indicators of peripheral circulatory movement, using a thermister and an apparatus for measuring tissue blood flow based on the thermal diffusion method. In the first project (Experiment A), five healthy subjects operated a chain-saw at a high working speed with-out actually cutting anything. In the second project (Experiment B), seven healthy subjects were exposed to three different kinds of experiments with combinations of hand-arm vibration, noise and tool weight at about 15 degrees C room temperature. In the third project (Experiment C), the effects of tool weight and grip force were examined. In the fourth project (Experiment D), patients suffering from vibration disease were exposed to hand-arm vibration and the noise of a chain-saw for 2 minutes. In experiment A, the mean value of the normalized finger skin temperature decreased gradually with cyclic changes corresponding to each exposure and break period. Changes in finger blood flow had almost the same pattern as the changes of skin temperature, but the recovery of blood flow during a 30 sec break period was notable and a slight elevation of the base line was observed. In experiment B, the mean value for the normalized finger skin temperature decreased much more when the subjects operated a chain-saw at a high working speed than when they operated the chain-saw with the noise isolated by double hearing protection. On the other hand, the results obtained in experiment C indicated that the effect of tool weight should be considered as an important factor for investigating the acute changes in peripheral circulation. In experiment D, some patients showed an unusual pattern in the change of blood flow during a post exposure period which was not seen in healthy subjects.

Adult↗