The Kurume Medical Journal
Online ISSN : 1881-2090
Print ISSN : 0023-5679
ISSN-L : 0023-5679
37 巻, SUPPLEMENT 号
選択された号の論文の17件中1~17を表示しています
  • Tsunetaka Matoba
    1990 年 37 巻 SUPPLEMENT 号 p. i
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
  • JUKKA STARCK, JUSSI PEKKARINEN, CHANG CHUN LIU
    1990 年 37 巻 SUPPLEMENT 号 p. S1-S11
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    Transmission of vibration from the handle of the tool to the handarm system was investigated by measuring vibration in pairs from the source and from the wrist and head. The frequency response function was applied to describe the transmission properties. The measurements were taken at work places to evaluate the effect of different work-related factors on the transmission. Laboratory measurements were conducted to evaluate the effect of different grip forces and the use of protective gloves on the transmission. The field measurements comprised five different groups of workers whose exposure to vibration was evaluated and whose observed symptoms of vibration-induced white finger (VWF) was compared to the predicted ones based on the exposure data and on ISO 5349. The comparison of the prevalence data was in good agreement for the forest workers. The ISO method seemed to underestimate the genesis of VWF in workers who had to use high grip forces and for whom the vibration comprised high values of impulsiveness. The present results suggest that the frequency response function as independent of the input signal may thus describe factors important to the transmission of vibration.
  • TADAYOSHI SAKURAI
    1990 年 37 巻 SUPPLEMENT 号 p. S13-S22
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    Chain saws were first used in Kyusyu in 1956 for cutting down trees and sawing timber in the national forests. In 1961, some workers complained of symptoms due to the vibrations, but countermeasures were not taken untill later. The working system and payment system in those times were different from the systems, today. The magnitudes of the chain saw vibrations were very large and the chain saws were operated for many hours, each day. Workers with VWF (vibration induced white finger) had to continue to operate the chain saws without restriction. Vibration disease is related primarily to the vibration of the tools, but also to the transmission of the vibration to the workers. From the official data on chain saws used in national forests, vibration transmission to the body was determined for workers from 1956 to 1984 by comparing the vibration magnitude on the body during work with modern chain saws and during vibration loading tests with an electro-dynamic shaker in the laboratory. The vibrations transmitted to the body in some rule in the observation. If the working posture of chain saw operator was the same as today, the vibration transmission was determined from the tool vibration, tool weight, joint fixation and orientation of the hands and the hands and the arms to the handle (joint elasticity). Older chain saws had 20 to 30 times larger vibration magnitudes than modern chain saws, and were also 2 to 3 times heavier. The vibrations transmitted to the foreheads of earlier workers were approximately the same magnitude as the vibrations at the back of the hands of present workers. Also the daily and annual hours of chain saw use were very long, and there were not sufficient measures to protect from the cold. The vibration in the former days led to more symptoms and lesions than in present times.
  • SYOGORO NISHI
    1990 年 37 巻 SUPPLEMENT 号 p. S23-S32
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    The characteristic symtoms of vibration disease, such as Reynaud's phenomnon and palmar superhydrosis, are associeted with a sympathetic hyperactivity. This paper discusses the possible sites and mechanisms of the vibration stress-induced facilitation and disinhibition in the sympathetic nervous system, particularly at the levels of the spinal cord and sympathetic ganglion. At the level of the preganglionic neurons, vibration stress may facilitate the activity of the alpha-1 adrenoceptors that mediate the slow excitatory postsyn-aptic potential and the spike-afterdepolarization. If the sympathetic hyperactivity is in part due to disinhibition, it could be produced by inhibition of the activity of the alpha-2 adrenoceptors that mediate the slow inhibitory postsynaptic potential in preganglionic neurons. At the level of the ganglion, muscarinic and peptidergic tranmission may be facilitated in vibration disease.
  • MASAYUKI IKI, NORIO KURUMATANI, TADASHIGE MORIYAMA, AKIRA OGATA
    1990 年 37 巻 SUPPLEMENT 号 p. S33-S44
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    It is well known that there are wide individual variations in the susceptibility of human hearing to noise exposure. The hearing of male forest workers were examined with vibrationinduced white finger (VWF) as an indicator of noise susceptibility of hearing. The results were as follows : 1. Hearing losses at 4 and 8 kHz in subjects with VWF were greater than those of unaffected men in a matched pair case-control study allowing for confounding due to differences of age and noise exposure. 2. The hearing loss at 4 kHz on the ipsilateral side of the hand with VWF was greater than the loss on the contralateral side in subjects with VWF in one hand. 3. The hearing loss at 4kHz in subjects with VWF progressed more rapidly during a fiveyear followup period than the loss in men with no history of VWF. These results indicate that the hearing of subjects with VWF was more vulnerable to noise than the hearing of subjects without VWF. It was suggested that a pathological change causing VWF, such as enhanced vasoconstriction due to elevated sympathetic nervous tone, could also cause this additional auditory vulnerability to noise exposure.
  • NORIAKI HARADA, MINORU NAKAMOTO, HIDEAKI KOHNO, HIROKAZU KONDO, MORISH ...
    1990 年 37 巻 SUPPLEMENT 号 p. S45-S52
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    Responses of the autonomic nervous system and the endocrine system to cold exposure were investigated. The subjects were all males, between 41 and 69 years of age. Seventy subjects with the vibration syndrome and vibration-induced white finger (VWF (+) group), 70 subjects with the vibration syndrome without VWF (VWF(-) group) and 70 healthy subjects (control group) were individually matched according to age. The subjects remained in a cold room at 7°C for 30 minutes. Catecholamines, cyclic nucleotides, thyroid hormones, ACTH and cortisol were measured before and during cold exposure. The VWF (+) group and the VWF (-) group had larger % increases of plasma norepinephrine, cyclic AMP, cyclic GMP, T3 and T4 levels than the control group. These findings indicate that the responses of the autonomic nervous system and the thyroid system to cold exposure are greater in the subjects with the vibration syndrome.
  • MARKUS FÄRKKILÄ, ILMARI PYYKKÖ, ESA HEINONEN
    1990 年 37 巻 SUPPLEMENT 号 p. S53-S60
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    Raynaud's phenomenon has been considered to be due to activation of the central sympathetic vasoconstrictor reflex, and may represent part of a larger dysfunction of higher autonomic centers. Symptoms, such as sweating disturbances, orthostatic hypotension, insomnia and impotence have been reported to be more common among vibration exposed workers. We studied 217 male forest workers and selected samples of this population for electromyographic (N=80), autonomic nervous system function, controlled breathing, tilting bed and valsalva manoeuvre (N=88) tests, and a full clinical neurological examination. Mean alcohol consumption was estimated to be 3.0 kg absolute alcohol/year. The total mean vibration exposure time was 14, 100 hours. The prevalence of Raynaud's phenomenon was 5%. The variations in heart rate (HRV) at rest and during deep breathing were observed. The traditional indexes of HRV (CV, CVS, MEAN) were computerized and calculated. There was a significant difference (p<0.001) between the HRV indexes during the deep breathing test in those with the shortest and the longest exposure to vibration. The values of HRV indexes were age dependent; and in multiple regression analysis, the total exposure time to vibration had an independent negative association to HRV. Also association of sensory neural hearing loss to Raynaud's phenomenon among vibration exposed workers indicates that there is an involvement of the central nervous system in the pathogenesis of vibration syndrome. The question, does vibration cause permanent changes in autonomic centers of the brain or do these centers only mediate vibration stress to end organs, remains unsettled.
  • TSUNETAKA MATOBA, TATSUYA ISHITAKE
    1990 年 37 巻 SUPPLEMENT 号 p. S61-S71
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    Vibration disease due to hand-held vibratory tools has various symptoms and signs which can be characterized by the severity. They include disorders of the central and autonomic nervous systems, as well as peripheral system disorders. The mechanism of Raynaud's phenomenon in vibration disease is proposed to be: Vibration and cold affect the local vessels and nerves directly, leading to enhanced release of chemical vasoconstictors. Vibration, noise, cold, ergonomic and biodynamic conditions, and emotional stress during work result in disorders of the central and autonomic nervous systems. In the early stages, the autonomic nervous system may be stimulated, and in the later stages it is suppressed. When local vessel injuries and disorders of the central and local autonomic nervous mechanisms controlling the vessels occur, vasospasms in the fingers develop when the whole body is exposed to cold. The cardiovascular system, other than the peripheral circulatory system, may adapt to vibration stress. The adaptation subsides 7 to 8 years after discon-tinuation of the use of hand-held vibratory tools.
  • An Experimental Study of Peripheral Circulation while Operating Chain-saws
    TAKASHI MIYAKITA, HAJIME MIURA, MAKOTO FUTATSUKA
    1990 年 37 巻 SUPPLEMENT 号 p. S73-S83
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    From the viewpoint of elucidating the etiological mechanism of vibration-induced white finger (VWF), a model experiment was designed using a chainsaw 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 chainsaw at a high working speed without actually cutting anything. In the second project (Experiment B), seven healthy subjects were exposed to three different kinds of experiments with combinations of handarm vibration, noise and tool weight at about 15°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 handarm vibration and the noise of a chainsaw 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 34 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 chainsaw at a high working speed than when they operated the chainsaw 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.
  • MASSIMO BOVENZI
    1990 年 37 巻 SUPPLEMENT 号 p. S85-S94
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    Two experiments were carried out to investigate the cardiovascular responses of vibration-exposed workers to autonomic stimulation. In the first experiment blood pressures, heart rate and systolic time intervals (STI) were measured during a cold test in 63 vibration-exposed foundry workers and 41 controls. STI, such as total electromechanical systole (QS2I) and left ventricular ejection time index (LVETI), were found to be shorter in the vibration-exposed workers with and without vibration white finger (VWF) than in the controls, both at rest and during cold provocation and recovery .(p<0.001). A significant inverse relationship between urinary excretion of free catechol-amines and the duration of STI was observed under resting conditions (0.001<p<0.03). In the second experiment, the above mentioned cardiovascular parameters were measured in 11 grinding operators with VWF and 11 controls during a hand grip test, an arithmetic test and an orthostatic test. Finger systolic pressures (FSP) during local cooling to 30, 15 and 10°C were also measured. QS2I and LVETI were more abbreviated in the VWF subjects than in the controls at rest and during both the circulatory stress tests and the recovery periods (0.001<p<0.05). The reduction in FSP by local cooling from 30°C to 15 and 10°C was greater in the VWF workers than in the controls (p<0.001). Significant correlations were observed between the reduction in FSP at 15 and 10°C and the duration of STI during circulatory stress activities (p<0.01). A multiple regression analysis pointed out that vibration exposure was the major determinant of STI during circulatory stress, while the importance of age and smoking and drinking habits in predicting STI was negligible. The findings of these studies suggest that the level of cardiac sympathetic activity is increased in VWF workers in comparison with controls. These experimental results are consistent with those of other investigators, indicating that excessive sympathetic reflex activity plays an important role in the pathogenesis of VWF.
  • LARS ERIK LINDBLAD, LENA EKENVALL
    1990 年 37 巻 SUPPLEMENT 号 p. S95-S99
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    In healthy subjects the physiological vasoconstriction to local cooling has been linked to sympathetic adrenoceptors of the alpha2-subtype. The present study was designed to determine if the vasoconstriction in response to local cooling in patients suffering from vibration white fingers can be diminished by alpha2-adrenoceptor inhibition. Six men with vibration white fingers, verified in a cold provocation test, were examined. To study the effect of local skin cooling blood flow was measured with laser doppler technique on the dorsum of dig. II or III. The temperature of the laser doppler probe was regulated by Peltier elements. Temperature could be lowered from 30°C to 20°C within 30s. Measurements were performed before and after local inhibition of the alpha2-adrenoceptors. This was achieved by the introduction of the selective alpha2-adrenoceptor inhibitor, rauwolscine, into the finger skin by iontophoresis. During control conditions local cooling consistently resulted in a marked vasoconstriction. Inhibition of the alpha2-adrenoceptors by rauwolscine completely abolished this effect. The present data indicate that substances inhibiting alpha2-adrenoceptors may be of therapeutic value in patients with vibration white fingers.
  • HANNU VIROKANNAS
    1990 年 37 巻 SUPPLEMENT 号 p. S101-S107
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    In the present study autonomic function was observed by measuring cardiovascular reflexes. The quiet breathing test, the deep breathing test and the Valsalva manoeuvre were used. The aim was to study the effects of long-term exposure to hand-arm vibration on the cardiovascular reflexes . The study group included 47 workers (lumberjacks and railroad workers) who were exposed to hand-arm vibration. 36% of the subjects had vibration induced white finger (VWF). Comparisons were also made with 5 primary Raynaud's cases. The changes of the R-R interval in the quiet and deep breathing tests had a significant negative correlation with the ages of the subjects. In all the results there was no evidence that hand-arm vibration could cause autonomic dysfunction in general, but there were signs that it could reduce the autonomic function among workers who are susceptibility to developing white finger reactions. Also, it is possible that the primary Raynaud's cases had reduced cardiovascular reflex responses.
  • NIELS OLSEN
    1990 年 37 巻 SUPPLEMENT 号 p. S109-S116
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    Vibration exposed workers with and without vibration-induced white finger (VWF), subjects with primary Raynaud's phenomenon and nonexposed controls were investigated in the present studies. The applied stimuli comprised cold stimuli, vibration exposure, and postural stimuli. The digital vasomotor responses to these stimuli were objectively quantified by measurements of finger systolic blood pressure and relative capillary blood flow rate in the skin of the finger. The results indicate that hyperreactivity of the central sympathetic nervous system may function as an/the abnormal element of the reflex mechanisms triggering the predominant portion of the vasoconstriction in episodic arterial closure of VWF. The hyperreactivity of the central sympathetic nervous system may be induced by prolonged exposure to handarm vibration, possibly by activation of the vibration elicited central sympathetic vasoconstrictor reflex mechanisms.
  • TADASHI NAKAMURA, YOSHIAKI HAYASHIDA
    1990 年 37 巻 SUPPLEMENT 号 p. S117-S122
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    The effects of several stressors on arterial blood pressure (BP), heart rate (HR), renal sympathetic nerve activity (RSNA) and renal blood flow (RBF) in conscious male rats were investigated. When conscious rats were exposed to smoke, the BP increased with marked decreases in HR and RBF. RSNA increased several times above the control level. During muscarinic blockade, smoke exposure reversed the HR response to an increase without any change in the RSNA. The results indicate that smoke exposure activates both the sympathetic and parasympathetic nervous systems. Whole body vibrations evoked increases in BP, HR and RSNA at frequencies less than 16 Hz. Higher frequency vibrations seemed to evoke no cardiovascular responses. It is suggested that cardiovascular responses to whole body vibration involve primarily the sympathetic nervous system.
  • TSUNETAKA MATOBA, HIROSHI KUWAHARA
    1990 年 37 巻 SUPPLEMENT 号 p. S123-S126
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
  • MARKUS FÄRKKILÄ, ILMARI PYYKKÖ
    1990 年 37 巻 SUPPLEMENT 号 p. S127-S128
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
    Vibration syndrome, or traumatic vasospastic disease, arose in Finland in the 1960s; when chain saws became lighter and more effective, and a whole day of exposure was possible. Vibration exposed workers have been studied since 1972 in Finland, and there has been a change in the prevalence and severity of vibration induced symptoms among forest workers (Pyykkö et al. 1986). As the vibration syndrome does not develop by only one mechanism (Färkkilä, 1978), the treatment and prevention is dependent on the factors causing the symptoms. In Finland the patient with vibration syndrome is compensated only when the following criteria are fulfilled : 1) he has been exposed to vibration long enough to develop the syndrome, and 2) all other diseases have been excluded, such as primary Raynaud's disease, collagen diseases, injuries and thoracic outlet syndromes. The patient with vibration syndrome is compensated only, when there are findings in at least two different tissues or organs, like white fingers as a sign of vasospastic disease, and EMG changes as a sign of neuropathy. The impairment from vibration induced white fingers or numbness is considered mild, and the estimated degree of invalidity is only 10-20 per cent. The patient is expected to work in professions without vibration exposure. In Finland autonomic symptoms and neck and shoulder symptoms are considered considered to be due to strenuous muscle work, temporary reversible stress and not linked to vibration exposure. Most patients are treated by general practioners who recommend lighter work, physiotherapy or drugs without compensation. If the patient fullfills the above criteria, the insurance company will pay for the treatment of symptoms which are definitely due to vibration exposure. All vibration exposed workers have had compulsory annual health examinations for hearing loss and hand arm symptoms paid for by the employer.
  • MASSIMO BOVENZI, ANTONELLA ZADINI
    1990 年 37 巻 SUPPLEMENT 号 p. S129-S130
    発行日: 1990/06/12
    公開日: 2009/08/11
    ジャーナル フリー
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