Epidemiological surveys suggest an important role for niacin in the causes of Parkinson’s disease, in that niacin deficiency, the nutritional condition that causes pellagra, appears to protect against Parkinson’s disease. Absorbed niacin is used in the synthesis of nicotinamide adenine dinucleotide (NAD) in the body, and in the metabolic process NAD releases nicotinamide by poly(ADP-ribosyl)ation, the activation of which has been reported to mediate 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Parkinson’s disease. Recently nicotinamide N-methyltransferase (EC2.1.1.1) activity has been discovered in the human brain, and the released nicotinamide may be methylated to 1-methylnicotinamide (MNA), via this enzyme, in the brain. A deficiency in mitochondrial NADH:ubiquinone oxidoreductase (complex I) activity is believed to be a critical factor in the development of Parkinson’s disease. MNA has been found to destroy several subunits of cerebral complex I, leading to the suggestion that MNA is concerned in the pathogenesis of Parkinson’s disease. Based on these findings, it is hypothesized that niacin is a causal substance in the development of Parkinson’s disease through the following processes: NAD produced from niacin releases nicotinamide via poly(ADP-ribosyl)ation, activated by the hydroxyl radical. Released excess nicotinamide is methylated to MNA in the cytoplasm, and superoxides formed by MNA via complex I destroy complex I subunits directly, or indirectly via mitochondrial DNA damage. Hereditary or environmental factors may cause acceleration of this cycle, resulting in neuronal death.

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Objectives: The purpose of this study was to examine trends in induced abortions in Japan.
Methods: The Ministry of Health, Labour, and Welfare compiled data on induced abortions, live births, and the population of women aged 15–49 years. These data were provided by 47 prefectures in Japan and were used to examine the number of induced abortions and various characteristics of women who received abortions from 1955 through 2001. We examined abortion numbers, abortion ratios (number of legal abortions per 1,000 live births) and abortion rates (number of legal abortions per 1,000 women aged 15–49). We were particularly interested in examining abortion trends among adolescents. These trends were also compared to those in the United States.
Results: A total of 341,588 legal induced abortions were reported in Japan in 2001, representing a 2.5% increase from 1998 to 2001. From 1998 to 2001, the abortion ratio (292) increased by 5.4%; from 1996 through 2001, the abortion rate (11.8) increased by 8.3%. Women less than 20 years old contributed most to these increases. In 1999, the abortion ratio among Japanese adolescents was 5.7 times as high as the ratio among U.S. adolescents, while the abortion rate among U.S. adolescents was 1.8 times as high as the rate among Japanese adolescents.
Conclusions: Recent increases in induced abortion among Japanese women may be related to several factors, including changes in sexual behavior among adolescents and a decline in their use of contraceptives. More appropriate educational efforts and interventions are needed to prevent unintended pregnancies.

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Purpose: It is known that a moderate to large volume of alcohol produces deterioration in obstructive sleep apnea (OSA), however, no consensus has been achieved with respect to the influence of a moderate volume of alcohol on mild to moderate OSA. In this study, we investigated the influence of alcohol on OSA-associated parameters in healthy middle-aged males drinking a moderate volume of alcohol (<1 g alcohol/kg bodyweight per day).
Methods: Subjects were 23 healthy males (mean age of 46.0) with a habitual ingestion of moderate amounts of alcohol. Respiratory sleep parameters were measured through the fitting of an Apnomonitor III (Chest Inc.) and portable sleep monitoring device (Actiwatch: AMI Inc.) to subjects on three nights; an alcohol-free night, a night on which they drank alcohol with dinner, and a night on which they drank alcohol within 30 minutes before retiring to bed. The measurements were categorized into the early and late halves of assumed sleep for analysis.
Results: The apnea-hypopnea index was significantly higher when drinking alcohol before retiring [mean (SD): 7.8 (8.2) events/hour] than the values on the alcohol-free day [2.9 (4.5) events/hour] and when drinking alcohol with dinner [3.8 (5.3) events/hour]. Furthermore, drinking alcohol before retiring resulted in lower arterial blood oxygen saturation (SpO₂) during the early half of sleep [94.8 (1.4) %] when compared to the values on the alcohol-free day [95.7 (1.3) %] and drinking alcohol with dinner [95.4 (1.6) %]. In addition, the percentage of time with SpO₂ <92% (hypoxic event) during the early half of sleep [4.9 (9.3) %] was significantly higher than the values on the alcohol-free day [1.2 (1.8) %] and when drinking alcohol with dinner [1.4 (1.8) %].
Conclusion: These results suggest that moderate ingestion of alcohol within 30 minutes before retiring aggravates OSA-associated parameters in healthy males.

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Objectives: In utero and lactational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) results in a wide variety of developmental effects in pups at doses much lower than those causing overt toxicity in adult animals. We investigated the relationship between tissue concentrations of TCDD in dams and fetuses and developmental effects on pups.
Materials and Methods: Pregnant Long-Evans rats were given TCDD at a single oral dose of 12.5, 50, 200, or 800 ng of TCDD or [³H]-TCDD/kg bw on gestation day (GD) 15. Dams were sacrificed on GD16 and GD21, and the tissue concentrations of TCDD were measured in dams and fetuses. Pups were sacrificed on postnatal day (PND) 49 and PND63 for males and PND70 for females, and the reproductive effects and tissue concentrations of TCDD were determined.
Results: The sex ratio (male/female) on GD21 was significantly reduced at 50 ng TCDD/kg and at 12.5 and 50 ng TCDD/kg at birth, but not at other doses. Delayed puberty was observed in males at 200 ng TCDD/kg and in males and females at 800 ng TCDD/kg. Anogenital distance, testis weight, epididymal sperm count, sperm motility, and ejaculated sperm count were not affected. Estrous cyclicity was not different from that of the control in any treatment group. A dose-dependent decrease in weight of seminal vesicle and prostate on PND49 was observed. Prostate weight was significantly decreased at 800 ng TCDD/kg. At this dose, maternal body burden and TCDD concentration in fetuses were 290 pg TCDD/g and 52 pg TCDD/g on GD16, respectively.
Reduced prostate weight is a sensitive and commonly observed endpoint so that the body burdens of dams and fetuses at the LOAEL of this endpoint could be served as the basis for establishing TDI for dioxins.

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Objectives: To determine the prevalence of cases and episodes of needlestick injury among three groups of health care workers in the past one-year, the level of knowledge on blood-borne diseases and universal precautions and the practice of universal precautions. Other factors associated with the occurrence of needlestick injuries and the reporting of needlestick injuries were also analysed.
Methods: A cross-sectional study was conducted in May 2003 to study the needlestick injuries among 285 health care workers (doctors, nurses, medical students) in a public teaching hospital in Negeri Sembilan, Malaysia.
Results: The prevalence of needlestick injuries among the respondents was 24.6% involving 71 cases i.e. 48.0% among doctors, 22.4% among medical students, and 18.7% among nurses and the difference was statistically significant (p<0.001). There were a total of 174 episodes of needlestick injury. Prevalence of episode of needlestick injuries was highest among doctors (146%), followed by nurses (50.7%) and medical students (29.4%). Cases of needlestick injuries attained lower scores on practice of universal precautions compared to non-cases (p<0.001). About 59% of cases of needlestick injury did not report their injuries.
Conclusions: The study showed that needlestick injuries pose a high risk to health care workers and it is underreported most of the time. Many needlestick injuries can be prevented by strictly following the practice of universal precautions.

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Objectives: To prepare a dietary recommendation for young Japanese for the prevention of coronary heart disease, we surveyed the dietary habits, serum lipids, serum fatty acids and blood pressure levels among male and female students.
Methods: In this study, 175 male and 246 female university students were interviewed for the frequency of consumption of selected food items and the habit of skipping breakfast. Serum fatty acids were analyzed by gas chromatography.
Results: The frequencies of consumption of dishes cooked with oil and intake of vegetables were higher in female students than in male students. Serum n-6 polyunsaturated fatty acids were slightly higher in female students than in male students while that of serum n-3 polyunsaturated fatty acids was 6.4% in both sexes. For both males and females, those who skipped breakfast at least once a week were less likely to consume vegetables and fruits than those who did not. Female students who skipped breakfast were also less likely to consume fish and had lower composition of n-3 polyunsaturated fatty acid and higher systolic and diastolic blood pressure levels than males. For female, the intake of milk and dairy products correlated inversely with systolic blood pressure levels and the intake of n-3 polyunsaturated fatty acids correlated inversely with diastolic blood pressure levels. For males, the intake of fruits and consumption of dishes cooked with oil correlated inversely with systolic and diastolic blood pressure levels.
Conclusion: Our findings suggest that increased intake of fish, milk and dairy products, fruits and vegetables from early adulthood and a regular dietary pattern are important to reduce the risk factors for coronary heart disease.

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A general delay in menarche in female athletes has been confirmed based on comparisons of mean ages between athletes and non-athletes; however, it has not been possible to judge such delays individually. If delayed menarche could be evaluated for an individual, the athlete could be advised as to necessary precautions. In this study, the age at maximum peak velocity (MPV) of height, adopted as an index of physical maturation, was identified by the wavelet interpolation method (WIM). The relationship between the age at menarche and age at MPV of height in female athletes and non-athletes was then examined. For the athlete group, health examination records of 90 female ball game players in the first year of university in the Tokai area, all of whom had participated in national level competitions, were reviewed for the period from the first grade of elementary school until the final year of high school (from 1985 to 1996). A similar examination was conducted for the control group, among whom a final group of 78 female non-athletes were selected. The age at menarche was determined by questionnaires, and the longitudinal data for height and weight were obtained from the health examination records. Based on a comparison of the difference between the age at MPV of height and age at menarche in ball game players and the control group, a tendency was seen for the difference between the two ages to narrow as the age at MPV of height rose. A corrected regression evaluation of age at menarche against age at MPV of height was derived in the control group, and the evaluation system was applied to ball game players. The delay in menarche in ball game players could be individually evaluated.

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