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Tatsuro Ohta

Publications and source records attributed to Tatsuro Ohta.

13 recordsLinked to original sources
PubMed2005

Personality of seasonal affective disorder analyzed by Tri-dimensional Personality Questionnaire.

BACKGROUND: Although there have been numerous reports in personality of mood disorders, there have been few reports in regard with personality of winter seasonal affective disorder (SAD). Furthermore, no reports have been published concerning summer SAD personality characteristics. Thus, this study was conducted to assess the personality of winter and summer SAD using Tri-dimensional Personality Questionnaire (TPQ) that have been used in a variety of mental disorders. METHODS: A total of 6135 Japanese were evaluated with TPQ, the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Self-rating Depression Scale (SDS). Winter, summer and non-SAD groups were classified by SPAQ. We compared the difference of personality trait among these three groups in consideration of gender, age and SDS score influence. RESULTS: Winter SAD demonstrated higher "Novelty Seeking" and "Harm Avoidance"; summer SAD showed higher "Harm Avoidance" than the non-SAD group. "Harm Avoidance" in both SAD groups was re-analyzed using SDS score as a covariate, and "Novelty Seeking" in winter SAD using age as a covariate. As a result, the significance of high "Novelty Seeking" and high "Harm Avoidance" in winter SAD was excluded. However, "Harm Avoidance" remained the significant difference between summer and non-SAD. LIMITATION: SAD was diagnosed only by SPAQ and not by interview. The state-dependency of "Harm Avoidance" was not confirmed in identical patients over lapse of time. CONCLUSION: Patients with winter SAD have high "Harm Avoidance" dependent on the depressive state that is in accordance with non-seasonal depression. Patients with summer SAD have high "Harm Avoidance" possibly independent from the depressive state.

Adolescent↗
PubMed2004

How do individuals sleep around the world? Results from a single-day survey in ten countries.

BACKGROUND AND PURPOSE: To describe between-country differences in both the prevalence and type of sleep disorders seen across the globe, and to provide information on how impaired sleep impacts daytime functioning. PATIENTS AND METHODS: The study is a large-scale, global cross-sectional survey conducted on International Sleep Well Day (March 21), 2002. A standardized questionnaire was used in 10 countries under the guidance of local survey managers. In addition, the Athens Insomnia Scale (AIS) and the Epworth Sleepiness Scale (ESS) were completed. Subjects included in the study were adults from 10 countries representing different continents with clear variations in lifestyle. RESULTS: The total number of questionnaires collected was 35,327. Overall, 24% of subjects reported that they did not sleep well. According to self-assessments using the AIS, 31.6% of subjects had 'insomnia', while another 17.5% could be considered as having 'sub-threshold insomnia'. According to ESS scores, 11.6% of subjects were found to be 'very sleepy' or 'dangerously sleepy' during the day. CONCLUSIONS: Although there seem to be important global variations in the prevalence of insomnia, its symptoms and their management, about one in four individuals do not think they sleep well. Moreover, self-reported sleep problems could be underestimated in the general population. Overall, there is a need for increased awareness of the importance of disturbed sleep and the improved detection and management of sleep disorders.

Aging↗
PubMed2003

Psychiatric features of seriously life-threatening suicide attempters: a clinical study from a general hospital in Japan.

OBJECTIVE: Although attempted suicide is one of the strongest predictors of completed suicide, few Japanese studies have described psychiatric differences between those who attempt suicide by overdose (OD) and those who use more violent methods (MV). METHODS: A total of 22 consecutively admitted MVs were compared to 78 ODs. All patients were referred for psychiatric evaluation during the same 3-year period. RESULTS: The MV group was predominantly male (68%), whereas the OD group was predominantly female (72%). Using DSM-IV criteria, depressive disorders were most common in both groups, followed by psychotic disorders. The OD group had significantly more borderline patients. Contrary to previous reports, prior psychiatric contact was low in the MV group. MVs were more likely to complain of financial problems and to retain a definite wish to die after the attempt. CONCLUSIONS: This study identified meaningful differences between the two groups of patients who attempted suicide.

Adult↗
PubMed2003

Cross-regional survey of seasonal affective disorders in adults and high-school students in Japan.

BACKGROUND: In Asian countries, there is no epidemiological report on seasonal affective disorder (SAD) in different age groups and different geographic regions surveyed at the same time. The aim of this study was to estimate the prevalence rates of SAD and risk factors for SAD in adults and high-school students, with special reference to the difference of winter SAD between northern and southern regions in Japan. METHODS: A total of 3237 high-school students and 4858 workers living in Japan (31.3-43.5 degrees N) responded to this epidemiological survey using Japanese version of the Seasonal Pattern Assessment Questionnaire (SPAQ). RESULTS: The overall prevalence rates of winter SAD (subsyndromal winter SAD) and summer SAD (subsyndromal summer SAD) in high-school students were 0.91(2.21) and 0.81(2.57)%, respectively. In workers, these rates were 0.45(1.16) and 0.43(0.71)%, respectively. Although no regional difference was noted in high-school students with winter seasonal type, the estimated odds ratio of this type for northern workers was nearly 3-fold higher than the southern counterparts. The prevalence rates of each seasonal type were not significantly different between two sexes in both age groups. No clear dependence on latitude was seen with regard to summer SAD in both age groups. LIMITATIONS: The effect of climate on SAD could not be entirely excluded from geophysical factor as indexed by latitude. CONCLUSIONS: SAD was less common in adults than in high-school students. While latitude was a major determinant of winter type in adults, socio-cultural factors or other contributing factors might affect the development of this type in high-school students.

Adolescent↗
PubMed2003

Comorbidity in attention deficit-hyperactivity disorder.

Attention deficit-hyperactivity disorder (ADHD) has been noted for its high rate of comorbidity. The present study is the first report in Japan evaluating the proportion of comorbidity in ADHD cases presenting in the clinical setting, aiming at clarifying the picture of ADHD in Japan. The subjects consisted of 68 child and adolescent cases meeting criteria for ADHD (Diagnostic and Statistical Manual of Mental Disorders, 4th edn) under treatment at a child psychiatry clinic (IQ > 50, mental age >or= 4 years old). Disorders evaluated as comorbid disorders were mood disorders, anxiety disorders, elimination disorders, sleep disorders, tic disorders, oppositional defiant disorder (ODD), conduct disorder (CD), school refusal, and epilepsy. Comorbidity with mood disorders, anxiety disorders, ODD, and CD, were found to be lower than the high rates conventionally reported in North America. The lower age of the present subjects, primarily in infancy and elementary school age with few adolescent cases, and a bias towards milder cases from an outpatient clinic without inpatient facilities are believed to be factors accounting for this disparity. Furthermore, it was a notable fact that mentally delayed cases (IQ: 51-84) amounted to 34% of the cases, indicating the necessity to consider intelligence level when formulating a treatment strategy for ADHD.

Adolescent↗
PubMed2002

Investigation of cellular metallic elements in single neurons of human brain tissues.

The purpose of this report is to introduce the potential of synchrotron radiation X-ray fluorescence (SRXRF) spectroscopy, by describing the application of this method to mapping and quantification of metallic elements in neurons from brain tissues affected by Alzheimer's disease (AD). In this study, clear images of Fe, Zn and Ca within certain single neurons were obtained. There was a high degree of correlation between Zn and Ca in the groups of cells with lower and relatively higher levels of Ca. These results demonstrate that further investigation with larger numbers of neurons using SRXRF spectroscopy may contribute to advancing the knowledge of the mechanisms of metal-induced cell degeneration in human brain tissues, including those affected by AD.

Aged↗
PubMed2002

Attenuating effects of the isolated rearing condition on increased brain serotonin and dopamine turnover elicited by novelty stress.

Isolation and acute environmental change are risk factors in human depression. In the present study, we investigated the differences in the brain monoamine activity of rats between two rearing conditions, isolated and group. Moreover, we examined the responses to novelty stress. Male F344 rats aged 11 weeks were divided into the above two groups. Four weeks later they were further divided into non-stress and stress groups. The latter received 20 min exposure to novelty stress. Isolation significantly changed brain monoamine levels, with the levels of dopamine (DA) in the nucleus accumbens and midbrain, dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the midbrain, and 5-hydroxyindoleacetic acid (5-HIAA) in the hippocampus increasing. Serotonin (5-HT) levels also increased in all brain areas except the raphe nuclei. HVA levels in the raphe nuclei decreased. Novelty stress significantly altered brain monoamine levels. DA, DOPAC, and HVA levels in the prefrontal cortex decreased, as did those of 5-HT in the prefrontal cortex and hippocampus. DA levels in the nucleus accumbens increased. Isolation attenuated the enhanced brain monoamine turnover elicited by novelty stress. The enhanced DA turnover ratio in the prefrontal cortex of the group-reared group was attenuated in the isolated-reared group, and the unchanged DA turnover ratio in the nucleus accumbens of the group-reared group declined in the isolated-reared group. The enhanced 5-HT turnover ratio in the prefrontal cortex, nucleus accumbens, and hippocampus of the group-reared group was attenuated in the isolated-reared group. Isolation may exacerbate adaptation to stress, and be related to the etiology of human depression.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2002

Influence of aging and social isolation on changes in brain monoamine turnover and biosynthesis of rats elicited by novelty stress.

Aging is a risk factor of human depression. Middle-aged or older men are vulnerable to adverse life events and an absence of social contact and easily become depressed. In the present study, we investigated the influence of aging on responses to life events in socially isolated conditions. We applied isolation-rearing (4 W) to two age groups, older (18 M) and younger (11 W), of male F344 rats that had been reared in a group and then examined responses to novelty stress (20 min). Changes in brain monoamines and their metabolites such as dopamine (DA), serotonin (5-HT), dihydroxyphenylacetic acid (DOPAC), homovanilic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA) were measured in six regions: the prefrontal cortex, nucleus accumbens, hippocampus, amygdala, midbrain, and raphe nuclei. MANOVA was carried out for rearing condition, age, and novelty stress. Isolation significantly changed monoamines and their metabolites, except in amygdala and raphe nuclei. Aging significantly altered them in all regions, although novelty stress did not. In the amygdala and midbrain, isolation significantly changed monoamine biosynthesis, with monoamine turnover remaining unchanged. In the prefrontal cortex and nucleus accumbens, aging significantly altered turnover, while biosynthesis remained unchanged. Novelty stress significantly varied only the turnover in the prefrontal cortex. The interaction between isolation and aging indicated that aging influences changes in turnover and biosynthesis elicited by isolation primarily at the center of the mesolymbic DA system, the midbrain, and in raphe nuclei of the 5-HT system. In peripheral regions of the mesolymbic system, aging primarily affects changes in turnover induced by isolation.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2002

Evaluating mental fatigue in patients with obstructive sleep apnea syndrome by the Maastricht Questionnaire.

Mental fatigue in patients with obstructive sleep apnea syndrome (OSAS) was investigated and compared with subjects without OSAS. The study series comprised 189 habitual snoring patients and 75 controls. To measure subjective mental fatigue and somnolence, subjects were asked to complete the Maastricht Questionnaire (MQ) and the Epworth Sleepiness Scale (ESS), respectively, and patients also underwent diagnostic polysomnography. According to the apnea and hypopnea index, patients were classified into the following groups: primary snorers, or having mild, moderate, or severe OSAS. The lowest MQ and highest ESS scores were found in those patients with severe OSAS. It is proposed that the lowest MQ score is due to mental fatigue impairing awareness in patients with severe OSAS, probably because of attention loss.

Female↗
PubMed2002

Rapid eye movement-localized apnea in a female patient with chronic insomnia.

A middle-aged female patient with chronic insomnia showed rapid eye movement (REM)- localized obstructive sleep apnea. She visited the Sleep Disorders Clinic and complained of insomnia with loud snoring. Once, in the past, her sleep complaints had disappeared after weight reduction but, 6 months later, she complained of excessive daytime sleepiness. Overnight polysomnography revealed REM-localized apnea. Careful follow up is strongly recommended for a female patient with chronic insomnia who shows REM-localized apnea.

Disorders of Excessive Somnolence↗
PubMed2002

Plasma biopterin levels and depressive state in pregnancy and the early puerperal period.

Plasma total biopterin and tetrahydrobiopterin levels of 14 normal pregnant and 15 normal puerperal women (within 1 week after delivery) were measured. In the first group, total biopterin levels were already increased (average: 18.2 pmol/ml) in the second trimester and remained high until the early puerperal period. In the second trimester, the ratio of tetrahydrobiopterin to total biopterin levels decreased to 72.3% and even further to 66.1% in the third trimester. This tendency continued until the puerperal period. Compared with the control group (12 healthy nonpregnant women), total biopterin levels increased during pregnancy and the puerperal period (p < 0.001), and the ratio in the third trimester and the early puerperal period decreased (p < 0.001). The depressive state according to Zung's score appeared most markedly in the third trimester with a mean score of 48, and tended to recover to a mean score of 36.2 in the early puerperal period. In this period, a correlation was found between Zung's score and the total biopterin levels (r = 0.80), and the ratio of tetrahydrobiopterin levels to the total biopterin levels (r = -0.92). In the early puerperal period, total biopterin levels were higher in subjects with Zung's scores > or = 36 (p < 0.001); the ratios of this group were lower than those of subjects with Zung's scores <36 (p < 0.001). Plasma biopterin levels in pregnancy and the early puerperal period closely resembled those of patients with mood disorders who show depressive symptoms from a psychoneurological perspective. Therefore, it seems possible that a depressive state in pregnancy and the early puerperal period has the same pathology as depression.

Adult↗