In previous papers we reported that endocrine disrupters (EDs) such as diethyl stilbesterol (DES), 4, 4'-isopropylidene diphenol (Bisphenol A: BPA), bis (2-ethylhexyl) phthalate (EHP) and p-nonylphenol (NP) stimulated proliferative responses and cytokine productions of murine spleen cells and thymus cells in vitro. In this paper we report the effect of EDs on murine macrophage functions in vitro. DES, BPA, EHP and NP stimulated thioglycolate-induced peritoneal exudate cells (macrophages) to produce cytokines such as interleukin (IL)-1, IL-6, IL-12, tumor necrosis factor and macrophage chemotactic protein-1. The effect of these EDs was observed at the concentrations of 10^-6-10^-8 M, and the maximum response was obtained at 10^-7 M. The accessory function for T cell activation and CD86 expression, an important molecule for accessory function, was enhanced in EDs-treated macrophages. These results suggest that EDs have modulating activities of macrophage functions.

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To investigate the effect of diesel exhaust or particle-free diesel gas on immune responses in IgE low responder mice, C57BL/6 mice immunized intranasally with sugi basic protein were exposed to diesel exhaust or diesel gas components. We evaluated the changes in lymphocyte subpopulations, cell proliferation, chemokine production of cervical lymph nodes cells, and antigen-specific-antibody levels in plasma. Exposure to diesel gas decreased the percentage of CD4⁺ and TCR-β⁺ T cells of cervical lymph nodes from immunized mice. Culture supernatants of cervical lymph nodes cells from diesel gas-exposed mice had significantly increased levels of macrophage inflammatory protein-1α and thymus and activation-regulated chemokine, but exposure to diesel exhaust did not affect it. Antigen-specific IgG2a titers in plasma were significantly enhanced after their exposure to diesel exhaust or gas. In contrast, exposure to diesel exhaust or gas markedly decreased antigen-specific IgG1 titers in immunized mice. These facts indicate that concurrent exposure to allergen and diesel exhaust or diesel gas modulates chemokine production in cervical lymph nodes cells and antibody production in plasma differentially.

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Exposure to Magnetic Fields (MF) may affect the health of workers in an occupational environment. However, there is no clear evidence that the emission of MF from the visual display terminals (VDT) affects workers' mental status or induces stress in office environments. The purpose of our study was to investigate whether exposure to the MF during VDT work affects mental fatigue or induces stress related to psycho-physiological changes in workers. Thirty-seven students were voluntarily recruited to participate in this study. We created experimental conditions that a pair of the liquid crystal display (LCD) terminals separated by screens was closely placed in front of the visual suface of the cathode ray tube (CRT) units. All participants were not able to recognize whether the power of the CRT Units was ON or OFF while they worked with the LCD terminals. When the CRT unit was ON, participants who worked with the LCD terminal were called CRT-ON group. On the other hand, when the CRT unit was OFF, participants who worked with the CLD terminal were called CRT-OFF group. Incredibly short profiles of mood states (ISP) and subjective symptom questionnaires were used as indices of the mental fatigue as well as psychological stress before and after VDT work. Furthermore, salivary chromogranin A and urinary 8-hydroxydeoxyguanosine (8-OH-dG) were collected to measure physiological changes before and after VDT work. The results of the questionnaires and salivary and urinary stress markers showed that the exposure to the MF during VDT work did not significantly induce mental fatigue or psychological stress in comparison with the CRT-OFF group. Contrary to the results from the exposure, mood states of vigor decreased greatly (P<0.05) whereas the states of fatigue and confusion increased significantly (P<0.001) after VDT work. In the questionnaires for subjective symptoms, participants complained remarkably regarding 14 out of 25 conditions after VDT work. Moreover, urinary 8-OH-dG excretion increased significantly after VDT work. Taken together, the results of this study did not detect any bad health effects of MF exposure on the VDT participants but suggested that VDT work itself affects their mental fatigue and psychophysiological status.

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The purpose of our study was to investigate the social support network for working mothers, including physical, emotional and informational sources, and to discuss strategies to reduce stress caused by their multiple role strain. We asked 18 participants to fill in a questionnaire and conducted semi-constructed interviews. The results of this study showed that more than half of the working mothers want to continue their career because of self growth and the rewards from their job. Many mothers responded that a sympathetic understanding by their husbands, families and people at workplaces is essential to create a balance between their career and housework. As a result, their husbands mainly provide physical support in housekeeping and child caring, whereas their mothers provide physical and emotional support from knowledge based upon their own experience. Almost all working mothers complained of a shortage of nurseries and child caring facilities as well as limited availability of flexible services. In conclusion, the results of our study suggested that the identity of the traditional gender role needs to be changed to a contemporary one, like a husband fully participating in his child's rearing activities by reconsidering his working hours. Moreover, community services to support working mothers should be increased.

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We investigated the body cooling capacity of water-circulated cooling pants during lower body exercise in a hot environment. Five subjects were asked to ride a bicycle ergometer and to keep a work rate of 75 W continuously for 20 minutes. They then rest on the ergometer for 15 minutes, in a climate chamber kept at WBGT = 31.5℃. They repeated the same procedure three times under three different conditions; 1) wearing cooling pants with cold water supply; 2) wearing cooling pants without water supply; 3) wearing short pants instead of cooling pants. Esophageal temperature and heart rate of the subjects, when their cooling pants were supplied with cold water, were lower compared with the condition without water supply, and were almost the same as the condition wearing short pants. Water-circulated cooling pants should effectively cool the body at work where the worker has to wear pants that cover his legs to prevent injury.

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The aim of this study was to examine the effects of bone metabolism impairment after a gastrectomy, as well as the effects of dietary life and physical activity on bone density, in order to obtain basic information on lifestyles that prevent osteoporosis. The study subjects were 27 male patients who had been diagnosed as having gastric cancer at a university hospital and had received a gastrectomy. All subjects gave their informed consent. The level of the bone metabolism impairment was examined by bone cell density measurement, ultrasound densitometer and by the measurements of bone metabolism parameters, i.e., BAP, DPD, NTx, corrected Ca. Physical activity was measured by the number of steps, and dietary life was investigated using a questionnaire. The SOS value, which is an index to the bone metabolism impairment, decreased 3 weeks after the gastrectomy. Although the SOS value recovered once, it decreased after 6 months again. Afterwards, it recovered to the preoperative level in 12 months. The levels of BAP, which are the osteogenesis markers, significantly decreased 3 weeks after the gastrectomy and increased three months later. DPD level, which is a bone resorption marker, increased significantly. The effect of physical activity and dietary life on the bone density was not recognized. Though the bone metabolism impairment appeared 3 weeks after the gastrectomy, the bone formation process after bone resorption was affected by individual differences. Consequently, it was impossible to clarify the factors of lifestyles which affect bone metabolism impairment.

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We observed two cases of nonrecurrent inferior laryngeal nerve (NRILN). Case 1, a 71 year old man was diagnosed as having papillary carcinoma. NRILN was found during his operation. It directly branched from the right cervical trunk of the vagus nerve at the level of the cricoid cartilage and then entered the larynx after running behind the thyroid gland. Case 2, a 64 year old woman was diagnosed as having primary hyperparathyroidism. In this patient, the NRILN branched at the level of the inferior pole of the thyroid gland, rose up beside the tracheal wall and entered the larynx. In both patients, preoperative CT scan and postoperative MR angiography revealed the aberrant right subclavian artery. A postoperative barium swallow test showed the compression of the esophagus by this anomalous artery in case 1. Although it is possible to predict the presence of NRILN by preoperative imaging tests, the branching level from the vagus nerve is unpredictable. Surgery must be performed with this point in mind, if the presence of NRILN is suspected.

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A simple method of biological monitoring has been developed for occupational benzene exposure. Personal benzene exposure monitoring using a passive sampler and GC/FID was carried out on 74 workers from a benzene-treated company. Their urines were collected before and after work-shift. After treatment of urine samples using solid phase extraction (SPE), trans, trans-muconic acid (t, t-MA) concentration in the elute was analysed by HPLC. Correlation between benzene exposure (X: ppm) and urinary t, t-MA concentration (Y: mg/g・creatinine) for non-smokers was Y=0.948X+0.586 (r=0.798, P<0.01) and Y=0.885X+0.894 (r=0.871, P<0.01) for smokers, respectively. The t, t-MA concentration on 1 ppm TLV exposure to benzene was estimated as 1.5 and 1.8 (mg/g・creatinine) for non-smokers and smokers, respectively. These values are in agreement with some investigators. This indicates that our simple method for biological monitoring of benzene exposure can be of great service.

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