Antioxidant effects of continuous intake of electrolyzed hydrogen water in healthy adults.

Chronic oxidative stress induces deterioration of health and a risk for the onset of various diseases. Previous clinical studies revealed that electrolyzed hydrogen water (EHW) is effective to reduce oxidative stress during hemodialysis in patients with chronic dialysis. In the present observational study, we investigated the antioxidant effects of a daily continuous intake of EHW in healthy adults. The concentrations of serum reactive oxygen metabolites-derived compounds (d-ROMs) and blood urea nitrogen in healthy volunteers (n = 64) who had a habit of intake over 500 mL/day of EHW at least 5 days a week for longer than 6 months were lower than those of age- and sex-matched controls (n = 470) without the habit of EHW intake. Oxidation stress index which the ratio between concentrations in d-ROMs and biological antioxidant potential was correlated with the serum concentration of high-sensitivity C-reactive protein or low-density lipoprotein cholesterol in the EHW group. These results suggest that the continuous intake of EHW induces antioxidant effects and may contribute to alleviate the risk of various oxidative stress-related dysfunctions and diseases in healthy adults.

Mental fatigue is linked with attentional bias for sad stimuli.

Previous studies have revealed that patients with chronic fatigue syndrome and affective disorders (such as depression and anxiety disorders) exhibit a vigilant attentional bias toward negative emotional stimuli. However, it remains unclear whether the change in an attentional bias for negative emotional stimuli can be induced by mental fatigue in healthy individuals. To address this question, we examined healthy participants' (n = 27) performance in a visual probe task and emotional Stroop task before and after the mental-fatigue-inducing task. We demonstrated that acute mental fatigue induced by the long-lasting working memory task led to the alteration of cognitive processing of negative emotional information in the healthy volunteers.

Hydrogen-rich water for improvements of mood, anxiety, and autonomic nerve function in daily life.

Health and a vibrant life are sought by everyone. To improve quality of life (QOL), maintain a healthy state, and prevent various diseases, evaluations of the effects of potentially QOL-increasing factors are important. Chronic oxidative stress and inflammation cause deteriorations in central nervous system function, leading to low QOL. In healthy individuals, aging, job stress, and cognitive load over several hours also induce increases in oxidative stress, suggesting that preventing the accumulation of oxidative stress caused by daily stress and daily work contributes to maintaining QOL and ameliorating the effects of aging. Hydrogen has anti-oxidant activity and can prevent inflammation, and may thus contribute to improve QOL. The present study aimed to investigate the effects of drinking hydrogen-rich water (HRW) on the QOL of adult volunteers using psychophysiological tests, including questionnaires and tests of autonomic nerve function and cognitive function. In this double-blinded, placebo-controlled study with a two-way crossover design, 26 volunteers (13 females, 13 males; mean age, 34.4 ± 9.9 years) were randomized to either a group administered oral HRW (600 mL/d) or placebo water (PLW, 600 mL/d) for 4 weeks. Change ratios (post-treatment/pre-treatment) for K6 score and sympathetic nerve activity during the resting state were significantly lower after HRW administration than after PLW administration. These results suggest that HRW may reinforce QOL through effects that increase central nervous system functions involving mood, anxiety, and autonomic nerve function.

Low putamen activity associated with poor reward sensitivity in childhood chronic fatigue syndrome.

Motivational signals influence a wide variety of cognitive processes and components of behavioral performance. Cognitive dysfunction in patients with childhood chronic fatigue syndrome (CCFS) may be closely associated with a low motivation to learn induced by impaired neural reward processing. However, the extent to which reward processing is impaired in CCFS patients is unclear. The aim of the present functional magnetic resonance imaging (fMRI) study was to determine whether brain activity in regions related to reward sensitivity is impaired in CCFS patients. fMRI data were collected from 13 CCFS patients (mean age, 13.6 ± 1.0 years) and 13 healthy children and adolescents (HCA) (mean age, 13.7 ± 1.3 years) performing a monetary reward task. Neural activity in high- and low-monetary-reward conditions was compared between CCFS and HCA groups. Severity of fatigue and the reward obtained from learning in daily life were evaluated by questionnaires. Activity of the putamen was lower in the CCFS group than in the HCA group in the low-reward condition, but not in the high-reward condition. Activity of the putamen in the low-reward condition in CCFS patients was negatively and positively correlated with severity of fatigue and the reward from learning in daily life, respectively. We previously revealed that motivation to learn was correlated with striatal activity, particularly the neural activity in the putamen. This suggests that in CCFS patients low putamen activity, associated with altered dopaminergic function, decreases reward sensitivity and lowers motivation to learn.

Imaging the passionate stage of romantic love by dopamine dynamics.

Using [(11)C]raclopride, a dopamine D2/D3 receptor antagonist, we undertook a positron emission tomography (PET) study to investigate the involvement of the dopaminergic neurotransmitter system when subjects viewed the pictures of partners to whom they were romantically attached. Ten subjects viewed pictures of their romantic partners and, as a control, of friends of the same sex for whom they had neutral feelings during the PET study. We administered [(11)C]raclopride to subjects using a timing for injecting the antagonist which had been determined in previous studies to be optimal for detecting increases in the amount of dopamine released by stimulation. The results demonstrated statistically significant activation of the dopaminergic system in two regions, the medial orbitofrontal cortex (mOFC) and medial prefrontal cortex, the former of which has been strongly implicated in a variety of rewarding experiences, including that of beauty and love. A positive correlation was obtained in mOFC between excitement levels and dopaminergic activation only in the love but not in the control condition.

Fatigue correlates with the decrease in parasympathetic sinus modulation induced by a cognitive challenge.

BACKGROUND: It is known that enhancement of sympathetic nerve activity based on a decrease in parasympathetic nerve activity is associated with fatigue induced by mental tasks lasting more than 30 min. However, to measure autonomic nerve function and assess fatigue levels in both clinical and industrial settings, shorter experimental durations and more sensitive measurement methods are needed. The aim of the present study was to establish an improved method for inducing fatigue and evaluating the association between it and autonomic nerve activity. METHODS: Twenty-eight healthy female college students participated in the study. We used a kana pick-out test (KPT) as a brief verbal cognitive task and recorded electrocardiography (ECG) to measure autonomic nerve activity. The experimental design consisted of a 16-min period of ECG: A pre-task resting state with eyes open for 3 min and eyes closed for 3 min, the 4-min KPT, and a post-task resting state with eyes open for 3 min and eyes closed for 3 min. RESULTS: Baseline fatigue sensation, measured by a visual analogue scale before the experiment, was associated with the decrease in parasympathetic sinus modulation, as indicated the by ratio of low-frequency component power (LF) to high-frequency component power (HF), during the KPT. The LF/HF ratio during the post-KPT rest with eyes open tended to be greater than the ratio during the KPT and correlated with fatigue sensation. Fatigue sensation was correlated negatively with log-transformed HF, which is an index of parasympathetic sinus modulation, during the post-KPT rest with eyes open. CONCLUSIONS: The methods described here are useful for assessing the association between fatigue sensation and autonomic nerve activity using a brief cognitive test in healthy females.

An autopsy case of macroglobulinemia complicated with syndrome of inappropriate secretion of ADH (SIADH) like hyponatremia, hypopituitarism and AL amyloidosis.

An 88-year-old male patient with macroglobulinemia was admitted to our hospital because of severe hyponatremia and unconsciousness. Laboratory findings showed decreased inhibition of antidiuretic hormone (ADH) and he was diagnosed with syndrome of inappropriate secretion of ADH (SIADH). Hyponatremia improved with only limitation of water intake and the patient was followed up on a continuing outpatient basis. However, soon after discharge from hospital, his legs started swelling with edema and hyponatremia worsened. He was re-admitted due to a fall at home. Hyponatremia was observed at re-admission. A CRH challenge test showed partial dysfunction of ACTH secretion. Corticosteroid therapy was performed, but the patient subsequently died from pneumonia. Pathological findings at autopsy revealed invasion of plasma cells and amyloid depositions in multiple organs, including the pituitary, adrenal cortex, heart, liver, kidney, lymph nodes and bone marrow. Consistent with these results, fibrosis was observed in the anterior lobe of the pituitary, suggesting that the autopsy findings were related to the clinical observations and diagnosis. This is the first reported case of macroglobulinemia complicated with multiple hormone dysfunction.

Effects of mild-stream bathing on recovery from mental fatigue.

BACKGROUND: Bathing in hot water is very common in Japan; people bathe in order to clean their bodies and to recover from physical and mental fatigue. However, there have been few reports examining the effects of bathing on recovery from mental fatigue. The purpose of this study was to examine the effects of mild-stream bathing on recovery from mental fatigue. MATERIAL/METHODS: During mild-stream bathing, a mild stream continuously passes from the sole to the calf, thigh, waist and back, thus providing a massage function. In a double-blinded, placebo-controlled, crossover experiment, 14 male healthy volunteers were randomized into normal bathing and mild-stream bathing experiments. After a fatigue-inducing mental task for 4 hours, subjects took a normal or mild-stream bath. RESULTS: Heart rate was higher, muscle stiffness in the waist was lower and plasma cortisol levels tended to be lower after mild-stream bathing when compared to normal bathing. In addition, after mild-stream bathing, mental task performance, as assessed by reaction times on an advanced trail making test, was better than that after normal bathing. CONCLUSIONS: The present results suggest that improved working memory processing, diminished waist muscle tone, and attenuated mental stress are induced by mild-stream bathing. Therefore, mild-stream bathing appears to be more effective for alleviating mental fatigue than normal bathing.