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R Kishi

Publications and source records attributed to R Kishi.

At least 73 records · Page 4Linked to original sources
PubMed1990

[Acute and chronic effects of organic solvents on the central nervous system. Use of psychobehavioral performance tests in the assessment of toxicity].

Neurotoxicity of organic solvents is one of the most important emerging issues in the field of occupational health. Psychological testing has been proven useful not only in clinical diagnosis but also in experimental and epidemiological studies. Although various psychobehavioral performance test batteries have been applied in the study of neurotoxicity of organic solvents during these last two decades among European countries and America, only few studies have been made on these in Japan. It is therefore considered very important to review the major papers published to date, clarify the issues being currently discussed, and propose important studies for future. The present paper provides a review of the results obtained by the application of behavioral performance tests in the study of solvent toxicity. The studies reviewed are classified into the following five parts: 1. psychological test batteries developed to date, 2. human experimental studies and experimental field studies on the acute toxicity of organic solvents, 3. epidemiological studies on industrial workers, 4. characteristics of the central nervous system dysfunction caused by organic solvents, and 5. prognosis of workers diagnosed as chronic organic solvent intoxication. The paper also discusses the applicability of psychobehavioral techniques and addresses issues in data collection in the study of the effects of solvent exposure on the nervous system.

Behavior↗
PubMed1989

Effects of acute lead acetate exposure on adult guinea pigs: electrophysiological study of the inner ear.

The effects on humans of lead acetate exposure may involve the cranial nerves, since vertigo and sensory neuronal deafness have been reported in lead workers; however, there exist only a few reports concerning the dose effects of lead acetate both on the cochlea and the eighth cranial nerve. The effects of lead acetate on the cochlea and the eighth nerve were investigated systematically using cochlear microphonics (CM), whole-nerve action potential (AP), and endocochlear potential (EP) in guinea pigs (male albino Hartley). Guinea pigs were injected with 2 ml of a 1% solution of lead acetate (20 mg) once a week for 1-5 weeks. The threshold of whole-nerve AP (N1) was elevated by injection of lead acetate, even 40 mg, and whole-nerve AP (N1) output voltage decreased after injection of 100 mg of lead acetate. On the other hand, no change was observed in CM after lead acetate injection (100 mg) or in EP after lead acetate exposure (40 mg). The blood concentrations of lead acetate were as follows (mean): control, 4.5 micrograms/dl; Expt 1, 80 micrograms/dl; Expt 2, 126 micrograms/dl; Expt 3, 142 micrograms/dl. We conclude that dysfunction of the eighth nerve is induced by high-dose lead exposure, but that lead exposure does not induce electrophysiological dysfunction of the organ of Corti and the stria vascularis.

Animals↗
PubMed1989

Placental transfer and tissue distribution of 14C-styrene: an autoradiographic study in mice.

The distribution of 14C-styrene was studied in the pregnant mouse using a whole body low temperature autoradiographic technique. In unsectioned tissues studied by liquid scintillation the concentrations of styrene and its metabolites in maternal and fetal blood and organs and in the placenta and amniotic fluid were determined. The organs which had higher concentrations of volatile styrene were maternal lung, kidney, liver, adipose tissue, and brain in mice killed shortly after injection. Non-volatile metabolites were localised in the lung, liver, kidney, gall bladder, and intestine. There were considerable amounts of radioactivity in the fetuses, though the concentrations were not as high in the maternal tissues. Fetal tissue levels were almost the same as maternal brain in mice killed from one to six hours after injection. The concentrations of styrene and its metabolites in placenta and amniotic fluid were about twice those in the fetal tissues. The placenta seems to play the part of a barrier for the fetus.

Amniotic Fluid↗
PubMed1989

[Association between parental occupational exposure and childhood malignancy. A review of epidemiological studies].

The question whether occupational exposure of parents to chemicals, electromagnetism and radiation causes malignant disease in their offspring has gained much interest. The findings to date, however, have been conflicting perhaps due to differences in the methods employed in these studies. A review was made on 16 case-control epidemiological studies. In 11 studies significant relation was observed between malignant tumor (leukemia, brain tumor and others) and occupational exposure to hydrocarbons, spray paint or other chemicals, ionizing radiation and electromagnetism. Conversely, no association was observed in five studies, in which different populations, different techniques, and different control groups were employed. The purpose of this paper is to examine the role of occupational exposure of the parents to chemicals and other agents in the development of malignant tumors in their offspring in relation to the employed epidemiological methodology.

Adult↗
PubMed1989

[Burnout syndrome of human services professionals--doctors, nurses, caregivers, teachers and clerks (1). Maslach Burnout Inventory: factor structures for samples of human services professionals, and its relation with Zung's Self-rating Depression Scale (SDS)].

During the past decade, burnout syndrome has been widely discussed not only in the USA but also in Japan. To evaluate the state of "burnout," two major scales are available: the first is the Maslach Burnout Inventory (MBI) developed by C. Maslach and the other is the burnout scale by A. Pines. MBI is suggested to be independent of and incompatible with Pines' burnout scale, but, Pines' burnout scale is predominantly used in Japan, while both are used in the USA. Since hardly any studies of burnout using MBI have been made in Japan, we measured and analyzed MBI to evaluate the burnout state of doctors, nurses, caregivers, teachers and clerks who are engaged in "human services professions." The available data were subjected to factor analysis, reliability analysis and multiple regression analysis using Zung's Self-rating Depression Scale (SDS). The following results were obtained. 1) The factor analysis showed that the factor loading pattern was similar to that of Maslach's, but two different factors were emerged in addition to the standard factors in the intensity subscale. 2) In the relationship with the state of depression, burnout is closely related to depression but simultaneously has its own factors. This suggest that burnout is not a subtype of the depressive state.

Allied Health Personnel↗
PubMed1988

Neurobehavioural effects and pharmacokinetics of toluene in rats and their relevance to man.

The present study was designed to determine the critical concentrations in blood and brain associated with specific behavioural changes during and after exposure to toluene. The effects of a single four hour exposure to toluene on signalled bar press shock avoidance in rats were tested. Rats exposed to 125, 250, and 500 ppm toluene showed a decline in conditioned avoidance responses at 20 minutes exposure compared with the pre-exposure baseline, although they recovered to almost the same level of performance as that before exposure. Exposure to 1000 ppm toluene for about four hours and 2000 ppm for two hours produced a concentration related increase in incorrect responses, acceleration of the reaction time, and decreases in the effective avoidance response rate. Beginning at 4000 ppm toluene exposure, the response rate increased; thereafter, it gradually decreased and finally slight ataxia was observed. After 4000 ppm exposure, all rats showed signs of excitation such as a pronounced increase in response rate. From analysis of the temporal courses of the blood and brain toluene concentrations during and after each exposure, excitative performance decrements were noticed in rats with blood and brain concentrations about 27 micrograms/ml blood and 32 micrograms/g respectively. Anaesthetic performance decrements were seen when the blood toluene concentration increased to 120 micrograms/ml and that of the brain reached about 160 micrograms/g. According to our results, the effects on the central nervous system are considered to be a function of both the exposure concentration and its duration, which are closely related to the increase of brain and blood toluene concentration.

Animals↗
PubMed1987

Chromium content of organs of chromate workers with lung cancer.

The content of chromium was measured in organs of six chromate workers who had worked in a chromate chemical manufacturing plant, had been exposed to a considerable amount of chromium for over 10 years, and had died of lung cancer. The chromium in the lungs of workers averaged 51.5 micrograms/g (range 24.8-210 micrograms/g), while levels in the lungs of non-exposed controls were 0.07-1.01 micrograms/g. Organs other than the lungs of the workers also had more chromium than those of the controls. Moreover, it was apparent that the metal remained in the lungs long after exposure to chromate had ceased.

Adult↗
PubMed1986

[Effects of toluene vapors on signaled bar press shock avoidance performance in rats].

The effects of single exposure to toluene on signaled lever press shock avoidance behavior in rats were tested during and after exposure. The results obtained were as follows: Rats exposed to 125, 250 and 500 ppm toluene showed a decline in conditioned avoidance responses at 20 min exposure as compared to the pre-exposure baseline, although they recovered to almost the same level of performance as that before exposure. Exposure to 1,000 ppm toluene produced an exposure duration related to the increase in the number of total lever presses and the decrease in the effective response rate. The number of total lever presses increased drastically after 2,000 ppm toluene exposure. Effective avoidance response rate decreased to about 70% compared to the pre-test performance. Beginning at 4,000 ppm toluene exposure, the response rate increased, thereafter it gradually decreased and finally slight ataxia was observed. After 4,000 ppm exposure, all of the rats showed signs of excitation such as marked increase in the response rate. Acceleration of the reaction time was remarkably observed after 1,000 and 2,000 ppm exposure. As a whole, in the case of toluene exposure, concentration-related increases in lever presses and decreases in the effective avoidance response rate beginning at 1,000 ppm were observed. Animals showed excitatory response at 1,000 and 2,000 ppm toluene exposure and at other levels such as 4,000 ppm they showed depressive behavior. The effects were closely dependent on toluene concentration and exposure duration.

Animals↗
PubMed1985

[The effects of tetraethyl lead on behavior in rats].

The effects of 10 mg/kg and 5 mg/kg intraperitoneally administered triethyl lead on rats were observed through measurement of the following: changes in body weight, passive aggressiveness, wheel running activity, the performance level of Rota-Rod Treadmill, and emotional responses in the open field. The results obtained were as follows: Weight losses of TEL-treated rats were recorded from 2 days after injection to 20 days after injection. Scores of passive aggressiveness were drastically increased following administration of TEL. Maximum passive aggressiveness was observed 4 days after injection and it continued until 13 days after injection. Wheel running activity was decreased for 2 days after injection. It was observed that TEL-treated rats showed extreme reaction on the wheel running activity test for about 30 days after administration. Endurance on the Rota-Rod Treadmill was significantly reduced in the 10 mg/kg group. The amount of defecation, ambulation and rearing of the treated group as measured by covariance analysis did not differ from that of the controls. The whole time course of intoxication and the precise measurement of neurotoxicity due to TEL could be followed using the techniques of behavioral toxicology.

Aggression↗
PubMed1984

An experimental study of the effects of lead acetate on hearing. Cochlear microphonics and action potential of the guinea pig.

Guinea pigs were poisoned with repeated i.p. injections of 1% lead acetate. After 5 weeks, the animals were examined electrophysiologically by using cochlear microphonics (CM) and action potential (AP). The thresholds of maximum voltage of N1 in the AP of the animals injected with a total of 100 mg lead acetate were elevated about 15 dB and increased N1 latency was also observed. However, no significant changes in those of CM were found. The results suggest that lead acetate not only induces damage to the peripheral nerves, but also to the cranial nerves.

Action Potentials↗
PubMed1984

[A chronobiological study on toluene anesthesia in mice].

An experimental study of toluene exposure was performed on mice at various times of the day using the righting reflex and blood concentration as indicators. One hundred and sixty ICR mice were housed 8 mice per cage for 3 weeks with free access to food and water under a dark-light cycle consisting of alternate 12 hr periods of darkness and light: the dark period beginning at 7:00. The exposure was begun when the mice were 8 weeks old. They were exposed to 10,000 ppm of toluene for 40 min at 4:00, 10:00, 16:00 and 22:00, and they were sacrificed at the end of the exposure, after 3 min or after 30 min. The duration of anesthesia was 200.2 +/- 15.4 (sec) at 4:00, 361.1 +/- 21.5 (sec) at 10:00, 335.1 +/- 18.5 (sec) at 16:00 and 309.2 +/- 19.8 (sec) at 22:00. The duration of anesthesia at 4:00 was shorter than that of the other times of the day statistically (p less than 0.01). With regard to the toluene concentration in blood, there was no significant difference between those mice sacrificed at the end of exposure and those sacrificed after 3 min.

Anesthesia, Inhalation↗