Increased intake or supplementation of vitamin D is often recommended for normal bone health; however, its preventive effect on osteoporosis has not been fully evaluated. The aim of this review is to gather evidence of the efficacy of the optimization of vitamin D nutrition in preventing osteoporosis and osteoporotic fractures. PubMed was used for searching the relevant literature using the MeSH terms “Bone Density (limited to “human”, “female”, and “English” literature)” or “Fractures (limited to “human”, “age ≥45 years”, and “English” literature)”, and “Vitamin D”. The searches yielded 19 randomized controlled trials (RCTs), nine cohort studies, 19 case-control studies, 19 cross-sectional studies, and one meta-analysis. We attempted to answer three questions: 1) does increased vitamin D intake prevent bone loss in peri- and postmenopausal women?, 2) does increased vitamin D intake prevent osteoporotic fractures in the elderly?, and 3) does increased vitamin D intake positively affect peak bone mass attainment in young women? The answer to questions 1 and 2 is that a vitamin D intake of 10–17.5 μg/day (400–700 IU/day) or more is effective in preventing bone loss in late postmenopausal women and an intake of 17.5–20 μg/day (700–800 IU/day) or more together with a calcium supplement reduces the risk of osteoporotic fractures. For question 3, some lines of evidence support the negative effect of low vitamin D nutrition on the attainment of peak bone mass in young women. Further studies are needed to clarify the effect of vitamin D in this age group.

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Mercury is a metal that has long been used because of its many advantages from the physical and chemical points of view. However, mercury is very toxic to many life forms, including humans, and mercury poisoning has repeatedly been reported. The main chemical forms of mercury are elemental mercury (Hg⁰), divalent mercury (Hg²⁺) and methylmercury (CH₃-Hg⁺), the toxicities and metabolisms of which differ from each other. Methylmercury is converted from divalent mercury and is a well-known neurotoxicant, having been identified as the cause of Minamata disease. It bioaccumulates in the environment and is biomagnified in the food web. Human exposure to methylmercury is mainly through fish and seafood consumption. Methylmercury easily penetrates the blood-brain barrier and causes damage to the central nervous system, particularly in fetuses. In this paper, we summarize the global mercury cycle and mercury metabolism, toxicity and exposure evaluation, and the thresholds for the onset of symptoms after exposure to different chemical forms of mercury, particularly methylmercury.

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Objective: In this study, we examined the characteristics of depression determination using four representative self-rating depression scales (Geriatric Depression Scale, GDS; Self-rating Depression Scale, SDS; Center for Epidemiologic Studies Depression Scale, CES-D; and Carroll Rating Scale, CRS) applied to Japanese community-dwelling elderly.
Methods: Subjects were 563 community-dwelling independent elderly living in twelve prefectures (330 males, 68.9±6.3 yr; 233 females, 68.1±5.8 yr).
Results: Depression rates determined using SDS (45.8%) and CES-D (68.6%) were higher than those determined using GDS (5.7%) and CRS (14.7%). Although correlations of depression scale scores among the four scales were significant and comparable (r: 0.61 (GDS vs. SDS, p<0.01) to 0.78 (SDS vs. CES-D, p<0.01)), the agreement in depression determination varied among scales (kappa coefficients: 0.05 (GDS vs. CES-D, p>0.05) to 0.46 (SDS vs. CES-D, p<0.01)).
Conclusions: Similarities in depression determination were found between GDS and CRS, and between CES-D and SDS. Depression rates determined on the basis of cut-off point for each scale were higher for CES-D and SDS than for GDS and CRS. Depression determination using a four-point rating scale may overestimate a slightly depressive symptom, compared with that using a two-point scale.

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Objectives: To measure the prevalence rate of, and determine the association between food and drink related behaviors and diarrheal illness among Japanese tourists, and assess their health care needs.
Methods: Eligible Japanese tourists (1,480) aged ≥15 years traveling in Chiangmai Province in the north, Ayutthaya Province in the center, Kanchanaburi Province in the west, Pattaya City in the east, and Krabi Province in the south of Thailand were enrolled in the study. Of these tourists, 1,318 consented to participate in this study and completed questionnaires in Japanese, giving a response rate of 89.1%.
Results: Among these Japanese tourists 21.3% had diarrheal illness, and of these tourists, 5.0% had classical travelers' diarrhea (TD), 11.8% had mild TD, 3.3% had good food and drink related behaviors, and 75.4% had moderate level of perception of diarrhea related to drinking and eating. Multiple logistic regression analysis indicated three significant diarrheal illness predictors: large number of previous visits to Thailand, longer stay in Thailand, and the experience of visiting other countries. Furthermore, 56.9% suggested providing an adequate number of toilets at tourist destinations; 53.9% suggested providing a 24-hour emergency call facility for a public ambulance; and 51.9% suggested providing garbage bins and garbage disposal facilities at tourist destinations.
Conclusions: TD still affects experienced Japanese tourists who visit Thailand. Although the proportions of the good levels of food and drink related behaviors were low, there were indications that Japanese tourists perceived the risk of contracting TD.

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Objectives: The aim of this study is to examine the effects of stone crushing in West Bengal, India, by comparing pulmonary functions of stone crushing workers with those of nonexposed agricultural workers.
Methods: Two hundred seventy two stone crushing workers and 123 nonexposed workers were analyzed in terms of occupational and personal histories, radiological findings, and pulmonary function test (PFT) results including slow vital capacity (SVC), forced vital capacity (FVC) and peak expiratory flow rate (PEFR). Different lung volumes i.e. FEV₁, FEV_1%, and flow rates i.e. FEF_{200–1200 ml}, FEF_25–75% and FEF_75–85%, were analyzed with regard to sex, smoking habit, work status, age and work duration.
Results: Contrary to our expectations, the incidences of suspected (2.94%) and definite (1.84%) pneumoconioses were very low and the results of some PFT such as those for FVC and FEV_1%, in the exposed group were better than those in the nonexposed group, although a gradual decline the performance in PFT was observed with age and work duration. There was a higher prevalence of restrictive impairment among the exposed group and a higher prevalence of obstructive impairment in the nonexposed group.
Conclusions: Some of the results were unexpected. Possible reasons for these include (i) undetectable concentrations of free silica in the stone dust in the work environment of the exposed workers and (ii) factors, such as climate, in the work environment of the nonexposed agricultural workers that could cause pulmonary impairment. Further protective measures should be undertaken to prevent pulmonary impairment in both groups of workers.

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Objective: In this study, we evaluated postpartum stress using a postpartum depression scale and by measuring the level of a stress-related substance, to clarify the relationship between the stress-coping capabilities of women in the final stage of pregnancy and their postpartum stress reactions.
Methods: Between April 2004 and October 2004, 54 women participated in a questionnaire survey and the measurement of their secretory immunoglobulin A (s-IgA) level as a stress-related substance two times in the final stage of their pregnancy (prepartum) and in their early puerperium (postpartum) was carried out. The questionnaire used in the prepartum stage included the following parameters: “basic features”, “Sense of Coherence (SOC)” and “Japanese version of the self-assessment depression scale” of Zung. The questionnaire employed in the postpartum stage included the following parameters: “course of delivery”, “Self-evaluation of delivery experience”, and “Postpartum depression scale”.
Results: The depression score was higher and the s-IgA level was lower in the low-SOC score group than in the high-SOC score group, indicating that stress reactions were more intense in the low-SOC score group.
Conclusion: It was revealed that stress reactions were more intense for women with a low SOC score. Moreover, the finding of a relationship between the low SOC score in the prepartum stage and depressive tendency suggests that women who are likely to develop depressive tendency can be predicted in the prepartum stage, and the significance of measuring SOC in the prepartum stage is thus suggested.

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Objectives: Kendo protective equipment is used without washing for a long time. Staphylococcus saprophyticus, Micrococcus luteus, and Bacillus sphaericus are frequently isolated from the mask (‘men’ in Japanese) of kendo protective equipment during one year. To investigate the bactericidal effects of electrolyzed acidic water on these three bacteria, we observed their cellular structures by electron microscopy after treatment with such water.
Methods: Each bacterium isolated from ‘men’ was treated with electrolyzed acidic water and then observed under scanning and transmission electron microscopes.
Results: When S. saprophyticus was treated with electrolyzed acidic water and its cellular structures were observed under a transmission electron microscope, ghost cytoplasm was observed, in which no ribosomal granules or fibrous DNA structures were present, and the cell wall inner layer was detached from the outer layer. Under a scanning electron microscope, the structure of the cell wall surface layer was wrinkled, and round pores were partially formed, indicating that the cytoplasmic structures were flushed out of the cells treated with electrolyzed acidic water through the pores formed in the cell wall. In M. luteus, the destruction of ribosomal granules and that of DNA fibers were observed to be similar to those of S. saprophyticus. For B. sphaericus, the effect of electrolyzed acidic water was investigated using vegetative cells. A dissociation between the cytoplasm and cell wall wrinkled the cell surface layer.
Conclusion: On the basis of above findings, electrolyzed acidic water was found to destroy the cellular structures of the three bacterial species frequently isolated from kendo men within a short time. Electrolyzed acidic water may be useful for disinfecting of kendo equipment.

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