Gender differences in sleeping hours and recovery experience among psychiatric nurses in Japan

In their attempts to balance sleep routines with service schedules, nurses working in shifts are at risk for developing sleep disorders. Furthermore, nurses often experience considerable stress. In recent years, research has acknowledged the importance of activities other than work, and in particular recovery experiences. Therefore, the current study aimed to explore gender differences in sleeping hours and recovery experience of psychiatric nurses from a 16-hour shift to two days off duty. We found that males went to bed late and that females rose slightly early on days where they worked night shifts. On average, the sleeping hours of males were about 2 hours longer than were those of females. Furthermore, sleeping hours was positively related to mastery in males, while in females working hours was negatively related to psychological detachment and relaxation. Before the night shift, females engaged more housekeeping and used short sleeping hours during rest to compensate for the lack of sleep. Thus, recovery experience had different relationships with various life activities between male and female nurses. The results highlighted the need for health management intervention

An Association Analysis between Mitochondrial DNA A10398G Polymorphism and Temperament in Japanese Young Adults

The mitochondrial (mt) DNA C5178A and A10398G polymorphisms have been reported to be associated with mental disorders such as bipolar disorder. However, the effects of these polymorphisms on temperament in healthy people are poorly understood. Evaluating healthy subjects can have the advantage of providing new strategies for maintaining psychological health and preventing mental illness. We examined the association between mtDNA polymorphisms and temperament in Japanese students. There was no significant difference in examined temperament when analysed by genotypes, 5178–10398 haplotypes, or sex. The subgroup analysis based on sex indicated that there was an interactive effect of the mtDNA A10398G polymorphism and sex on anxiety and obsession. This finding is preliminary and cannot exclude the possibility of false-positive due to small sample size (144 subjects) and multiple statistical testing. Further studies involving a larger sample size or other ethnic groups are necessary to confirm that mtDNA A10398G polymorphism can be a genetic factor for temperament

Preferable percentage body fat estimation equation for Japanese athletic children: Comparison using Japanese and non-Japanese specific equations

Objectives: To compare estimated percentage body fat (%BF) values from available equations and determine the preferable equation to be used in athletic and non-athletic Japanese children and adolescents. Methods: Body density (BD) of 250 non-athletic and 234 athletic boys and 292 non-athletic and 180 athletic girls (less than 18 years old) was determined by the underwater weighing method (UWW) and %BF estimated using the following equations: (1) Siri (Eq(Siri)), (2) Brozek et al. (Eq(Brozek)), (3) Lohman et al. (Eq(Lohman84)), (4) age- and gender-specific Lohman (Eq(Lohman86)) and (5) Tobe et al. (Eq(Tobe)). Using %BF values estimated from Japanese-specific Eq(Tobe) as the reference, estimated %BF values and estimation patterns were compared. Also, using < 5% in boys and < 15% in girls as a minimum level for ‘essential lipids’ and using the sum of two skinfolds developed for Japanese as criterion for obesity, likelihood of underestimation and sensitivity/specificity using each equation were determined. -- Results: Estimated %BF from the tested equations were significantly different to each other (P<0.01). Compared to Eq(Tobe), Eq(Brozek) and Eq(Lohman84) showed a considerable over- and underestimation in children with low %BF. Also Eq(Lohman86) showed gender differences in estimation pattern which may be attributed to ethnic differences in the timing of puberty. For athletic groups, proportions of underestimated individuals reduces when using Eq(Siri). -- Conclusion: Although further confirmation is required, Eq(Tobe) may be the preferred choice for %BF estimation in non-athletic Japanese children and Eq(Siri) for children who participate in regular physical training

Preferable percentage body fat estimation equation for Japanese athletic children : comparison using Japanese and non-Japanese specific equations

Objectives: To compare estimated percentage body fat (%BF) values from available equations and determine\ud the preferable equation to be used in athletic and non-athletic Japanese children and adolescents.\ud Methods: Body density (BD) of 250 non-athletic and 234 athletic boys and 292 non-athletic and 180 athletic\ud girls (less than 18 years old) was determined by the underwater weighing method (UWW) and %BF\ud estimated using the following equations: (1) Siri (Eq(Siri)), (2) Brozek et al. (Eq(Brozek)), (3) Lohman et al.\ud (Eq(Lohman84)), (4) age- and gender-specific Lohman (Eq(Lohman86)) and (5) Tobe et al. (Eq(Tobe)). Using %BF values\ud estimated from Japanese-specific Eq(Tobe) as the reference, estimated %BF values and estimation patterns\ud were compared. Also, using < 5% in boys and < 15% in girls as a minimum level for ‘essential lipids’ and\ud using the sum of two skinfolds developed for Japanese as criterion for obesity, likelihood of underestimation\ud and sensitivity/specificity using each equation were determined. --\ud Results: Estimated %BF from the tested equations were significantly different to each other (P<0.01).\ud Compared to Eq(Tobe), Eq(Brozek) and Eq(Lohman84) showed a considerable over- and underestimation in children\ud with low %BF. Also Eq(Lohman86) showed gender differences in estimation pattern which may be attributed to\ud ethnic differences in the timing of puberty. For athletic groups, proportions of underestimated individuals\ud reduces when using Eq(Siri). --\ud Conclusion: Although further confirmation is required, Eq(Tobe) may be the preferred choice for %BF estimation\ud in non-athletic Japanese children and Eq(Siri) for children who participate in regular physical training.\u