The evaluation of the density of the active sweat gland on the dorsum of the foot induced by iontophoresis of 1% pilocarpine was made repeatedly using the silastic impression mold technique in 83 subjects (52 normal volunteers: 24 subjects younger than 50 years of age and 28 subjects 50 years of age or older, 20 men and 32 women: 20 diabetic patients and 11 patients with other neurological disorders), from 12 to 82 years of age, and the reliability of such evaluation was assessed. After 8 to 14 days following the first evaluation, the second one was performed. The reliability was expressed as an intra-class correlation. The intra-class correlation was greater in the subjects 50 years of age or older (0.909) than in the subjects younger than 50 years of age (0.653). It was similar between males (0.921) and females (0.803). On the other hand, it was less in diabetic patients (0.543) than in the normal volunteers (0.857) and patients with other neurological disorders (0.809). The silastic impression mold technique is widely applicable in evaluating the sweat gland function. However, it should be kept in mind that the reliability is variable among the groups defined clinically and that it is low in the diabetic patients.

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Health hazards due to exposure to chromium in the chromium plating industry has been documented in only a few epidemiological studies. A prospective cohort study was conducted to examine the health hazards of chromium plating with a follow-up period of over sixteen years. Subjects were 1193 male metal platers in the small-scale chromium plating plants in Tokyo. They were divided into a chromium plater subgroup (n＝623) and non-chromium plater subgroup (n＝567) and were followed up from October 1976 through December 1992. The 95% confidence interval (95%CI) of the standardized mortality ratio (SMR) was used to evaluate statistical significance. In the chromium plating subgroup, the risk of chronic hepatitis or liver cirrhosis was significantly elevated (SMR 2.34; 95%CI 1.17－4.19) and a trend toward statistical significance was seen for the risk of lung cancer (SMR 1.18; 95%CI 0.99－3.04). No significantly elevated risk was seen in the non-chromium plating subgroup. We concluded that, as the number of disease-specific deaths was small, further follow-up is necessary.

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A 46-year-old housewife had complaints of insidiously progressive muscle weakness and paresthesia in the distal lower limbs. On neurological examination, a slight to moderate degree of muscle weakness with slight atrophy was observed in the bilateral intrinsic hand muscles. A severe degree of muscle weakness with moderate atrophy was observed in tibialis anterior, gastrocnemius and soleus muscles. Muscle stretch reflexes were decreased in the upper limbs and absent in the lower limbs, without pathologic reflexes. She had a steppage gait. Vibratory sensation was slightly decreased in the hands and moderately decreased in the feet. Touch, pain and temperature sensations were also moderately decreaised only in the feet. On laboratory examination, glycosuria (5.6 g/dl) was noted. Fasting blood sugar was 226 mg/dl with an elevated hemoglobin A_1C level (12.7%). The right median motor and sensory nerve conduction velocities were 14.8 and 20.3 m/sec, respectively, with a markedly prolonged distal latency. No muscle action potential was obtained from stimulation of the right tibial nerve. Also, no nerve action potential was elicited from stimulation of the right sural nerve. A fascicular biopsy of the right sural nerve revealed the presence of both demyelinated and remyelinated axons, and an onion-bulb formation with a marked decrease in the density of the myelinated fibers. Based on the neurological examination and nerve conduction studies of the family members, a younger sister, younger brother and an elder daughter of the proband were found to be affected by demyelinating polyneuropathy. Diabetes mellitus was not found among the family members with laboratory evidences of demyelinating polyneuropathy. Based on the family history, an uncle on the mother's side of the proband, the proband's grandmother and a younger daughter of a proband's brother were considered to be affected. The uncle and grandmother had diabetes mellitus. Therefore, we concluded that this family had HMSN type I with autosomal dominant inheritance. In the studies on fluorescence in situ hybridization, and restriction fragment length polymorphism of the genomic DNA of the proband, a DNA duplication in the 17p11.2-12 region was not observed. However, the direct sequencing analysis of DNA fragments from genomic DNA encoding the Po gene of the proband revealed a substitution of histidine for arginine at the codon 98 in the extramembranous domain of Po. She was heterozygous for the mutant allele and normal allele. Alterations in the tertiary structure of the extramembranous domain of Po may result in an impairment of the peripheral myelin compaction. This is the second Japanese family with the same mutation (Arg⁹⁸→His) of myelin Po as reported previously by us, and this type of case is rare in the literature. Therefore, the mutation at the codon 98 may play a critical role in the development of the myelin abnormality in HMSN type IB.

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We evaluated the image quality of three-dimensional (3D) spiral CT using a Somatom Plus CT scanner (Siemens, Germany). A T-shaped acrylate plastic model was made and scanning was performed with a table speed of 5 mm/sec for 24 seconds. The thickness of the X-ray beam was 5 mm with one second per rotation. The various images of the model were created based on the shaded surface display (SSD) method and the effect of threshold and rotation (spin and tilt) on the quality of the 3D images was studied. The increase of threshold caused a rapid decrease in the diameter of the stick observed on the film, and this phenomenon was particularly remarkable on the transverse stick and the junctional portion of the longitudinal stick. The change of spin or tilt did not affect the diameter of the stick on the film. It was found that the depth perception of the stick could be achieved with the gray scale technique. We concluded that the interpretation of the 3D spiral CT image obtained with SSD needs caution and the diagnosis should not be made only on this image.

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An analysis of the recent use of an Anonymous FTP Server in the University of Occupational and Environmental Health, Japan for the distribution of software and documents through Internet was examined. The following points were confirmed. The use of the Anonymous FTP server for receiving files from outside the university rapidly increased after making the Anonymous FTP server public. The average file transfer rate in use from outside the university was less than ten percentage points from that of local use. The time for local use was stabilized, but the time for use outside the university was variable.

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A formula to estimate ground level UV-B from meteorological data was developed for the purpose of utilization in ecologic and/or environmental epidemiologic studies. Estimated values were obtained for various regional points in Japan. There was a very high correlation (r＝0.98) between estimated and observed values at four weather stations during 1991－93. Ranks of the UV-B level for the 1990 year mean and decennial period means during 1961－1989 approximately equated ranks of latitude. However, ≧10% variation in period means or ≧10 difference in rank was observed at several regional points. Estimated UV-B level is affected by meteorological conditions including solar radiation and total ozone, and may serve as a refined and improved exposure index compared to conventional indices used in prior studies.

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Air condition systems are indispensable for amenity in the work environment. It is known that Legionella species are widely distributed in the water of cooling towers, and that the bacteria are responsible for community-acquired pneumonia (Legionnaires' disease) and for influenza-like symptoms (Pontiac fever). Furthermore, Legionella species are associated with building-related illness. In Japan, however, prevention and countermeasures are inadequate against legionellosis compared to those of Europe and the USA. This is because occupational and environmental medicine in Japan has not been based on a microbiological point of view, and that workplace inspections have not covered cooling towers. Therefore, Legionella species in the water of coolig towers have not been routinely monitored in the work environment. This review describes the microbiological characteristics of Legionella species, their habits in the environment, the source and route of infection, the pathogenesis, the symptoms and treatment of legionellosis, outbreaks of this disease throughout the world, and how to deal with this organism in the work environment to prevent legionellosis.

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In order to clarify the knowledge and skills necessary to become occupational physicians and the required under- and post-graduate education and training system, an AHP (Analytic Hierarchy Process) analysis was conducted in colloboration with 10 occupational physicians who had graduated from UOEH. After classifying the contents of their work and the necessary knowledge and skills necessary to fulfill their duties by the KJ method, the AHP technique was employed in order to determine the relative importance of 5 education and training courses: 'Under-graduate general education', 'Under-graduate medical education', 'The fundamental occupational health course', 'Post-graduate clinical residency', and 'On the job training'. Regarding knowledge and skills to fulfill the duties of an occupational physician, those of 'Social medicine', 'Information science' and 'Clinical medicine', in this order, were regarded as important. For the contents of an Occupational physician's work, 'Medical surveillance of workers' and 'Environmental management of workplaces' were evaluated as important. For the educational setting in order to master the necessary knowledge and skills, 'On the job training' was regarded as the most important, and then 'The fundamental occupational health course', and 'Post-graduate clinical residency' followed in this order.

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