Objective: Serum 25−hydroxyvitamin D [25(OH)D] is a vitamin D metabolite and a good indicator of vitamin D nutritional status. Low 25(OH)D levels accelerate age−related bone loss in women. The aim of this study was to assess 25(OH)D levels using population−based samples from women in a community in Japan. Subjects and Methods: Of all 187 adult women living on a solitary island (Niigata, Japan), 150 (80.2%) were enrolled in a cross−sectional study in early June 1998. After excluding 6 subjects who were undergoing treatment for osteoporosis, 144 female subjects were analyzed. Serum 25(OH)D₂ and 25(OH)D₃ were determined by high−performance liquid chromatography. The sum of 25(OH)D₂ and 25(OH)D₃ was calculated, yielding 25(OH)D, for which a concentration of less than 30 nmol/L was defined as vitamin D insufficiency. Demographic data such as age, height, weight, and body mass index (BMI) were also recorded. Results: The average age of the subjects was 61.3 years (SD 12.8), ranging from 21 to 87. The average concentrations of 25(OH)D₂ and 25(OH)D₃ were 0.5nmol/L (SD 3.2) and 64.6nmol/L (SD 17.6), respectively. The number of subjects with 25(OH)D concentration less than 30nmol/L was 4 of 149(2.7%). Serum 25(OH)D concentrations were not significantly correlated with age (r=−0.065, p=0.441) or BMI (r=0.086, p=0.310). Conclusion: The present population−based study confirms adequate levels of 25(OH)D and low prevalence of vitamin D insufficiency in Japanese women. Further research should be directed toward clarifying which dietary factors determine vitamin D nutrition.

抄録全体を表示

To evaluate the protective effects of Ginkgo biloba extract (GBe) which has antioxidant activity against peripheral neuropathy due to diabetes mellitus, slow axonal transport and morphology of sciatic nerve including endoneurial microvessels were examined in 12 rats with diabetes mellitus induced by streptozotocin (STZ, 60mg/kg, b.w., i.p.). Six of the diabetic rats were treated with 0.1% of GBe for 6 weeks from one week after the STZ injection. Serum glucose and lipid peroxide levels in GBe−treated diabetic rats were significantly lower than those in untreated diabetic rats (p<0.01, respectively), though the serum glucose level was higher than that in the control rats. L−[³⁵S] methionine pulse radiolabeling with subsequent gel fluorography demonstrated that mean velocities (Vmean) of actin and β−tubulin, i.e. slow component b(SCb) transport in untreated diabetic rats were significantly lower than those in control rats (p<0.05, respectively); mean diameter of axons in the former rats was significantly smaller than that in the latter (p<0.01). Vmean of actin transport in GBe−treated diabetic rats was significantly faster than that in untreated diabetic rats (p<0.05). Vmean of slow axonal transport was significantly correlated with mean diameter of axons in the three groups of rats combined (p<0.01). On electron microscopy, severe altered endoneurial microvessels decreasing in luminal area together with endothelial cell degeneration or hypertrophy, pericyte debris and basement membrane thickening were observed in untreated diabetic rats; on the other hand these findings were less prominent in the diabetic rats treated with GBe. It is suggested that GBe treatment may protect disturbed slow axonal transport and pathological alterations of peripheral nerve with abnormal endoneurial microvasculature from diabetes mellitus by antioxidant activity.

抄録全体を表示

To survey risk factors in coronary heart disease, we compared serum fatty acid composition and lipids for university students in Japan (33 males and 29 females) and in the Netherlands (20 males and 19 females). No significant differences were found between the mean levels of cholesterol (Chol) and triglycerides (TG) between the subjects in the two countries. The mean levels of polyunsaturated fatty acid (PUFA), monounsaturated fatty acid (MUFA) and saturated fatty acid (SFA) of Japanese students were similar to those of the Dutch students. In both countries, the levels of Chol showed a positive correlation with the levels of PUFA, n−6 PUFA, linoleic acid (C18: 2n−6), and arachidonic acid (AA, C20: 4n−6) but no correlation with the percentages of PUFA and the ratio of PUFA/SFA. On the other hand, the TG levels correlated inversely with the percentage of PUFA and the ratios of PUFA/SFA in both countries. When compared to those of Japanese students, low eicosapentaenoic acid (EPA, C20: 5n−3) and high AA were found in the Dutch students (p < 0.001, respectively). The total amounts of n−3 PUFA in the Dutch were significantly lower than those in the Japanese (p < 0.001) but no differences among those of n−6 PUFA. The ratios of EPA/AA and n−3/n−6 PUFA of the Dutch students were lower than those of the Japanese students (p < 0.001, respectively). The ratio of EPA/AA showed a positive correlation with EPA but not with AA in both countries. The levels of Toc which will decrease the risk of coronary vascular disease (CVD) were lower in Japan than those in the Dutch in both sexes (p < 0.01, respectively). These results suggest that the low EPA and high AA levels and the low n−3/n−6 PUFA ratio may lead to greater incidence of CVD.

抄録全体を表示

To identify life−related factors causing increased mortality, 2, 769 rural residents aged 29−77 were investigated through a self−administered questionnaire in 1990. Death certificates and migration information were inspected during the 4.5−year follow−up period. Age, obesity, life attitude, job, marital status, drinking and smoking habits, previous or current illness, and frequency of participation in health examinations were checked during the baseline survey. The person−year mortality rate was higher among irregular participants in health examinations than among regular participants both among males and females. From Cox’s multiple regression analysis, factors with a significantly high hazard ratio (HR) for mortality were irregular participation (HR=2.05), increase of age (HR=1.54, for 10 years), previous or current illness (HR=2.44), unemployment (HR=1.95), and living without a spouse (HR=2.61) for males; and for females they were having previous or current illness (HR=15.21) and living without a spouse (HR=2.94). Thus, irregular participation in health examinations, unemployment and aging showed a relationship with a higher mortality only in males. A previous or current illness and living without a spouse were related in both sexes.

抄録全体を表示

There is a general recognition of the role of low birthweight(LBW) as a major determinant of infant mortality rates. Since the rate of LBW has been increasing over the past fifteen years in Japan, we decided to ascertain the risk factors related to it, and also to verify whether or not maternal leisure−time physical activities including sports activities, before pregnancy and during gestation, affected the rate of LBW babies. In our study of the 2, 682 questionnaires delivered within a year to the Municipal Health Centers of the three cities chosen for this study, 1, 714 questionnaires were analyzed. The results in a univariate analysis showed that maternal height, pre−pregnancy weight, length of gestation, smoking, hospitalization before the 37th week of gestation, a history of LBW, and occupational activities were significantly associated with LBW. In logistic regression analyses, mothers of smaller stature, less pre−pregnancy weight, less length of gestation and mothers who were, furthermore, hospitalized before the 37th week of gestation, smoked, had previously delivered a LBW baby or had experienced stressful events during pregnancy were more likely to have LBW babies. The results showed that maternal leisure−time physical activities before and/or during pregnancy had no bearing on the delivery of a LBW baby.

抄録全体を表示