It has been reported that endocrine disrupters (EDs) have several biological activities, especially on endocrine systems. We studied the effect of EDs such as diethyl stilbesterol (DES), 4,4'-isopropylidene diphenol (BPA), bis (2-ethylhexyl) phthalate (EHP) and p-nonylphenol (NP) on murine spleen cells in vitro. DES, BPA, EHP and NP enhanced concanavalin A- and lipopolysaccharide-induced proliferative responses of spleen cells. The activity was most effective at the concentration of 10^-7M. These EDs stimulated both T cells and B cells. They also enhanced cytokine productions such as interleukin (IL)-4 and interferon-γ, and the total immunoglobulin G production of spleen cells. Furthermore, these EDs enhanced cytokine productions such as tumor necrosis factor and IL-1 by macrophages. These results suggest that EDs have a modulating activity on immune responses.

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The attenuation characteristics of the earplug using a dummy head (KEMAR; Knowles Electronics Manikin for Acoustic Research) were measured, when it was exposed to pure tones or broadband noises at three different sound pressure levels (SPLs) of 70, 80 and 90 dB SPL in the wide frequency range from 250 to 20k Hz. We ascertained the satisfactory capacity of noise attenuation except for from 10k to 14k Hz. The noise attenuation level increased with frequency until 2k Hz, became almost constant until 8k Hz, then decreased at around 10k to 14k Hz, and recovered in the range from 16k to 20k Hz. The frequency characteristics were identical among three different sound pressure levels and almost identical between pure tones and broadband noises. The change of frequency characteristics affected by the depth of the earplug that was inserted into the artificial ear canal of the KEMAR was also investigated. Measured sound pressure level by the built-in microphone in the KEMAR revealed a region in which the measured sound pressure levels were relatively higher around 10k Hz. The freguency of the region moved higher when the earplug was inserted more deeply. Therefore it was considered that this phenomenon was related to the resonance frequency of the cylinder-like cavity made between the end section of the earplug and the diaphragm of the built-in microphone.

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Australia is a developed country with a high standard of living, small population and large land area. Manufacturing is currently the largest economic contributor, although mining and agriculture are also significant industries. There are around 10 million employees in total, with retail trade and manufacturing being the largest employers. Manufacturing currently has the highest incidence of workplace injury, although around 5% of all Australian workers suffer from some kind of occupational disease or injury every year. Occupational Health and Safety (OHS) legislation is individually managed and enforced by the 8 states and territories. Training and registration for OHS professionals varies between the specialities and usually requires a combination of academic qualifications and workplace experience. Non-medical personnel constitute a large proportion of OHS professionals in Australia.

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A large number of lymphocytes are recruited to the sites of inflammation where they form an essential component for the response to infection, injury, autoimmune disorders, allergy, tumor invasion, atherosclerosis and so on. The recruitment of leukocytes into tissue is regulated by a sequence of interactions between the circulating leukocytes and the endothelial cells. Leukocyte integrins play a pivotal role in leukocyte adhesion to endothelial cells. During the process, the activation of integrins by chemokines is essential for integrin-mediated adhesion in which a signal transduced to the leukocyte converts the functionally inactive integrin to an active adhesive configuration. Such a regulation is most emphasized in inflammatory processes, in which leukocytes migrate from circulation into the tissue. The concept, concerning chemokines in diseases and health, would be an enormous help in clarifying pathological processes of inflammation as well as the new pharmacological approaches to more specifically control particular inflammation.

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Normal pressure hydrocephalus (NPH) is a clinical syndrome associated with dementia, gait disturbance and urinary incontinence. Gait disturbance is usually the initial sign and most important symptom, but its objective evaluation has not been established. We analyzed the gait of an idiopathic NPH before and after ventricular shunting with the gait analysis system. Before shunting, the stride was short and irregular, and the truncal movement was unsteady. Three-dimensional patterns of angular relationshiups between 3 joints, namely the ankle, knee and hip were small and irregular. The vector profile of floor reaction force showed a monophasic pattern with absence of the peak at toe-off. After shunting, the step enlarged and the truncal movement was steady. The three-dimensional patterns of angular relationships between the 3 joints were nearly normalized. The vector profile of floor reaction force showed an appearance of the peak at toe-off, which formed a biphasic pattern, similar to the pattern of a normal person. The gait analysis is a useful method to evaluate gait disturbance in idiopathic NPH.

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Two cases of Swyer-James syndrome are reported. Case 1; A 25-year-old man was admitted to our hospital to be treated for Mycobacterium avium infection. Chest X-ray film revealed hyperlucency in the right lower lung. High-resolution CT showed a low attenuation area and bronchiectasis in the right lower lobe. He had had two episodes of pneumonia in his childhood. 3D CT scan showed a narrowing of right lower pulmonary arteries. Case 2; A 65-year-old woman was admitted to our hospital with dyspnea on effort. Chest X-ray film revealed hyperlucency in the right lung. Chest CT scan on inspiration and expiration detected air-trapping, which is characteristic of this syndrome. In both cases, the volume of the hyper lucent lung was normal. From these clinical findings, we diagnosed these two cases as Swyer-James syndrome and in this paper described the clinical features and treatment.

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We report four cases of non-clostridial gas gangrene. All cases were associated with diabetes mellitus as the underlying disease. Case 1: a 60-year-old male developed an ulcerative lesion on the dorsum of his left foot. Peptostreptococcus asaccharolyticus, Citrobacter freundii and Staphyrococcus epidermidis were identified in culture from odoriferous pus. Case 2: a 81 -year-old female developed a lesion on her vulva spreading to the right lower abdomen. Bacteroides bivius, Peptostreptococcus asaccharolyticus and Streptococcus faecalis were identified in culture of the odoriferous pus. Case 3: a 80-year-old male developed a swollen area with ulcer on the right foot. Bacteroides fragiris, Enterococcus faecalis, Proteus mirabilis, Enterococcus avium and Enterococcus faecalis were identified by culture. Case 4: a 52-year-old female developed swelling of her left groin. Enterococcus faecalis and Streptococcus anginosus were identified in culture from the odoriferous pus. In all patients, a radiological examination revealed the presence of subcutaneous gas in the lesion. Prognosis of non-clostridial gas gangrene is usually poor. These four patients, however, all survived. Once an infectious sign is seen in the diabetic patient, it is important to discover a gas figure by using the radiological examination (plain film or computed tomography). Earlier diagnosis and debridement are the most important for a better prognosis. Because workers with diabetes mellitus are now increasing in number, occupational physicians should always keep in mind that a serious infectious disease like non-clostridial gas gangrene can develop even from minor accidental trauma, and they should control the working environment in the workplace where accidents often happen.

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Determining factors for adaptation to a new workplace in light of 3 cases that have taken early retirement due to occupational maladjustment are discussed. The character traits of these 3 cases are regarded as individual factors because of their conspicuousness. In regard to adaptation to new workplaces, two of my cases were unable to adapt in their previous workplaces because of their avoidant personality. They were also unable to adjust to their present workplaces. When the worker's character traits tend to cause occupational maladjustment, appropriate approaches including counseling and occupational adjustment should be recommended to the worker.

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Wistar male rats and ddY male mice were exposed to 500-10000 ppm of methyl bromide gas up to 8 hours, and the survival time and weights of brain, lung, liver, kidneys, spleen and testes were measured. The survival time decreased with the gas concentration almost exponentially. In general, rats had a longer survival time than mice under the same exposure concentration. Difference of survival time between rats and mice was remarkable at low concentrations but small at high concentrations. Spleen weight decreased significantly and kidney weights tended to increase at 2000 ppm or greater exposure concentrations. Difference between wet and dry lung weight in the exposure group was significantly greater than that in the control group, especially for high concentrations, which suggested pulmonary edema or bronchopneumonia.

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