Kiyohisa Takahashi

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The effect of ACTH and/or adrenalectomy on serotonin (5-HT)2 receptor binding sites was evaluated in the neocortex of rat forebrain. One day after the adrenalectomy or sham operation, ACTH (50 µg/day) was injected subcutaneously into adult male SD rats for 10 consecutive days. Saturation analysis showed that subchronic ACTH treatment significantly increased(More)
We tested whether the human Clock (hClock) gene, one of the essential components of the circadian oscillator, is implicated in the vulnerability to delayed sleep phase syndrome (DSPS) and non-24-hour sleep-wake syndrome (N-24). Screening in the entire coding region of the hClock gene with PCR amplification revealed three polymorphisms, of which two(More)
OBJECTIVES Depressive symptoms are observed in a relatively large series of patients with delayed sleep phase syndrome (DSPS). This study was undertaken to investigate the prevalence, characteristics, and factors associated with depressive symptoms among DSPS patients. METHODS This study targeted 90 consecutive patients (54 men, 27.1±9.2 years old)(More)
STUDY OBJECTIVES The objective of this study was to clarify sleep characteristics and pathophysiology in patients with delayed sleep phase syndrome (DSPS), which is a major circadian rhythm sleep disorder subtype. DESIGN Polysomnography was performed for 2 consecutive nights and core body temperature was sampled for 7 consecutive days, including the(More)
Recent studies have shown that functional variations in clock genes, which generate circadian rhythms through interactive positive/negative feedback loops, contribute to the development of circadian rhythm sleep disorders in humans. Another potential candidate for rhythm disorder susceptibility is casein kinase I epsilon (CKIepsilon), which phosphorylates(More)
OBJECTIVE The current study attempts to define the psychological features of patients with delayed sleep-phase syndrome (DSPS). METHOD We administered the Yatabe-Guilford test (Y-G test), Minnesota Multiphasic Personality Inventory (MMPI), Picture-Frustration study (P-F study) and Rorschach test to two groups, one of patients with DSPS (case group) and(More)
Delta wave deficits during sleep have been observed in patients with schizophrenia. Decreased slow-wave sleep is reported to be associated with negative symptoms. Frontal lobe dysfunction is also believed to underlie negative symptoms of schizophrenia. This study was designed to identify functional abnormalities in schizophrenia manifested on patients'(More)
This study aimed to identify brain regions with the least decreased cerebral blood flow (CBF) and their relationship to physiological parameters during human non-rapid eye movement (NREM) sleep. Using [(15)O]H(2)O positron emission tomography, CBF was measured for nine normal young adults during nighttime. As NREM sleep progressed, mean arterial blood(More)
Intracellular calcium concentrations ([Ca++]i) in blood platelets from 11 depressed patients and 11 healthy controls were investigated. The resting [Ca++]i of platelets from depressed patients was 69.4±2.9 nM while that from controls was 74.6±4.0 nM. Serotonin (5-HT), at a concentration of 10 µM, increased [Ca++]i by 129.2±3.9 nM in platelets from depressed(More)
This report concerns pathological astrocytic tubular structures (astrocytic tubules, As-Tbs) that coexist with glial filaments in astrocytic processes in brains with presenile-onset Alzheimer-type dementia. The formation of As-Tbs appears to be related to the duration of disease and the intensity of Alzheimer histopathology. In three cases in which the(More)