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Background:Orthostatic hypotension (OH) caused by autonomic dysfunction is a common symptom in older people and patients with idiopathic rapid eye movement sleep behavior disorder (iRBD). The orthostatic challenge test is a standard autonomic function test that measures a decrease of blood pressure during a postural change from supine to standing positions. Although previous studies have reported that changes in heart rate variability (HRV) are associated with autonomic dysfunction, no study has investigated the relationship between HRV before standing and the occurrence of OH in an orthostatic challenge test. This study aims to examine the connection between HRV in the supine position and the occurrence of OH in an orthostatic challenge test., Methods:We measured the electrocardiograms of patients with iRBD and healthy older people during an orthostatic challenge test, in which the supine and standing positions were held for 15 min, respectively. The subjects were divided into three groups: healthy controls (HC), OH-negative iRBD [OH (–) iRBD], and OH-positive iRBD [OH (+) iRBD]. HRV measured in the supine position during the test were calculated by time-domain analysis and Poincaré plots to evaluate the autonomic dysfunction., Results:Forty-two HC, 12 OH (–) iRBD, and nine OH (+) iRBD subjects were included. HRV indices in the OH (–) and the OH (+) iRBD groups were significantly smaller than those in the HC group. The multivariate logistic regression analysis for OH identification for the iRBD groups showed the model whose inputs were the HRV indices, i.e., standard deviation 2 (SD2) and the percentage of adjacent intervals that varied by more than 50 ms (pNN50), had a receiver operating characteristic curve with area under the curve of 0.840, the sensitivity to OH (+) of 1.000, and the specificity to OH (–) of 0.583 (p = 0.023)., Conclusions:This study showed the possibility that short-term HRV indices in the supine position would predict subsequent OH in iRBD patients. Our results are of clinical importance in terms of showing the possibility that OH can be predicted using only HRV in the supine position without an orthostatic challenge test, which would improve the efficiency and safety of testing.

Although low vitamin D status resulting from night work is a suspected cause of various health disorders, few studies have investigated the association between night-shift work and vitamin D status. Here, we examined serum 25-hydroxyvitamin D (25OHD) levels in 19 Japanese indoor workers, including night-shift workers, in blood samples collected at the annual medical checkup (late July) in a metal tool factory. Analyses were finally restricted to 14 male workers (33-59 yr) in 3 groups: fixed daytime work (n=6), and rotating shift work with (n=4) and without (n=4) night shifts. No significant differences in serum 25OHD levels were observed among the three groups (p=0.98, Kruskal-Wallis test). One to two participants in each group had 25OHD levels lower than the 20 ng/ml reference value for vitamin D deficiency even in summer. These results clearly indicate the need for large-scale studies to test the hypothesis that night-shift work is associated with lower 25OHD levels.

An Electret Condenser Microphone (ECM) fabricated by Micro Electro Mechanical System (MEMS) technology, or a silicon microphone, was employed as a novel apparatus for human pulse wave measurement. Since ECM frequency response characteristic, i.e. sensitivity, theoretically constant in the level at lower than resonance frequency as stiffness control, the slightest pressure difference at around 1.0Hz generated by human pulse waveform is expected to measure by this silicon microphone. However, with regard to MEMS-ECM as a single device, the difficulty arises in a possible sensitivity reduction due to a high input-impedance amplifier embedded in MEMS-ECM. We then determined the frequency response at around 1.0Hz, and based on this result we defined the compensation circuit by which the human pulse waveform was successfully obtained.

Summary Objective We investigated the effect of walking through woodland on salivary endocrinological stress markers, cortisol and chromogranin A (CgA). Design From 20 healthy males, saliva samples were collected immediately before and after the walk, and 20 min and 40 min after that. In addition, using visual analog scales, subjective perceptions of stress and of feeling tired and uplifted were evaluated. On another day, as a control, they sat around in their office and samples were collected at the same times. Salivary cortisol and CgA levels were determined by enzyme-linked immunosorbent assay (ELISA). Results Samples taken after the walk showed a significant increase in the levels of CgA. Meanwhile, there was no significant change in the levels of cortisol. In control samples, there was a statistically significant decrease in the levels of both CgA and cortisol. Feelings uplifted and tired increased and subjective perception of stress decreased significantly after the walk. During the control period, there were no such changes. Conclusion These findings suggest that, while walking in woodland becomes a physical stressor, such activity may also bring about feeling uplifted.

Using shogi, a representative table game popular in Japan, to model a stress situation, we investigated the modulatory effects of player characteristics on changes in the levels of cortisol and testosterone in the saliva of the players. Saliva samples were collected at the following time-points: (1) 30 min after awakening on the day of the shogi convention; (2) immediately before the game; (3) immediately after the game; (4) 30 min after the end of game; (5) 30 min after awakening the following morning. The study cohort comprised 90 healthy male university students who were members of a shogi club, who were subsequently classified into either the emotional strategy (Em) or cognitive strategy (Co) group based on their scores on a Lazarus-type stress coping inventory. Cortisol levels were significantly higher in the Em group than in the Co group the morning following the convention, and this difference was not affected by either outcome (victory or defeat) or perception (competitive or noncompetitive) of the match. A similar but non-significant trend was observed for testosterone levels. Our findings suggest that the Em group had a greater capacity to manage the stress from a shogi convention than the Co group.

Recently, Tai Chi, which is one of the Chinese traditional martial arts, has been receiving attention. The main feature of Tai Chi is its flowing movements including loosening up, relaxing, and practicing meditation with slow abdominal respiration. Tai Chi is widely taken as part of health-promotion activities or rehabilitation training, and significant mental and physical effects have been reported so far. In this review report, Tai Chi was confirmed to be beneficial not only as a rehabilitation training for old people or patients with various diseases but also as an exercise for healthy people. These findings suggest the potential of Tai Chi as a complementary and alternative therapy.

To investigate the influence of individual patterns of personality and behavior on the change in mood status after a brief period of Tai Chi exercise. The mood status in 22 healthy females was evaluated before and after a period of Tai Chi exercise using the Profile of Mood States (POMS) score. Patterns of personal behavior were also assessed by written questionnaire. In the type A behavior pattern group, the score for total mood disturbance decreased significantly after a brief period (20 min) of Tai Chi exercise. No change was observed in the type B behavior pattern group. These findings suggest that a brief period of Tai Chi exercise is mentally beneficial, particularly to individuals with type A characteristics.