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Biomedical subjects

M Okawa

Publications and source records attributed to M Okawa.

At least 19 recordsLinked to original sources
PubMed1995

Effects of vitamin B12 on human circadian body temperature rhythm.

To clarify the effect of vitamin B12 on the human circadian clock, five healthy male adults participated in two constant routine procedures, 2 or 3 weeks apart. In one, subjects received intravenous saline injections (placebo trial) and in the other, intravenous injections of methylcobalamin (MB12) (drug trial). Intravenous administration of MB12 increased rectal temperature in the later hours of the daytime during the constant routine. The activity did not change between treatments in any period during the constant routine. During the later hours of the constant routine, alertness assessed with visual analog scale was higher in the drug trial than in the placebo trial. The period in which drug treatment produced greater alertness almost coincided with that in which MB12 elevated rectal temperature. These results may provide evidence of an effect of vitamin B12 on the circadian clock.

Adult↗
PubMed1995

Enzymatic synthesis of mannobioses and mannotrioses by reverse hydrolysis using alpha-mannosidase from Aspergillus niger.

Various manno-oligosaccharides including alpha-D-man-(1 --> 2)-D man and alpha-D-man-(1 --> 2)-alpha-D-man-(1 --> 2)-D-man were formed when a highly concentrated mannose solution was incubated in the presence of alpha-mannosidase from Aspergillus niger. alpha-D-Man-(1 --> 2)-D-man and alpha-D- man-(1 --> 2)-alpha-D-man-(1 --> 2)-D-man were isolated by activated carbon chromatography followed by high performance liquid chromatography using an amino-silica column. In addition to the above oligosaccharides, alpha-D-man-(1 --> 3)-D-man, alpha-D-man-(1 --> 6)-D-man, and alpha-D-man-(1 --> 2)-alpha-D-man-(1 -->6)-D-man were also isolated.

Aspergillus niger↗
PubMed1995

Incidental Lewy body disease in a patient with REM sleep behavior disorder.

We studied an 84-year-old man with a 20-year history of nocturnal violent behavior during sleep, but no other clinically evident neuropsychiatric disorders. Polysomnographic investigations confirmed that he suffered from REM sleep behavior disorder (RBD). Histopathologic examination revealed he had Lewy body disease with a marked decrease of pigmented neurons in the locus ceruleus and substantia nigra. These histologic findings represent the first documented evidence of a loss of brainstem monoaminergic neurons in clinically idiopathic RBD and suggest that Lewy body disease might provide an explanation for idiopathic RBD in the aged.

Aged↗
PubMed1995

[Multiple colonic ulcers in a patient with Sjögren's syndrome].

A 25-year-old female with Sjögren's syndrome was admitted to our hospital because of fever and abdominal pain. Multiple colonic ulcers were demonstrated by gastrographin enema and colonoscopy. Histological examination revealed the presence of necrotizing vasculitis in the submucosal region. Large dose of prednisolone (60 mg/day) brought a prompt relief of her symptoms and an improvement of positive inflammatory signs. Pseudoaneurysm in the arteria colica media, which had been demonstrated by abdominal selective angiography at the time of diagnosis, became extinct after the steroid treatment. Healing of ulcers were also noted by colonoscopy. A variety of extraglandular symptoms has been reported in Sjögren's syndrome. Multiple colonic ulcers due to vasculitis are rarely complicated but may have a great impact on the prognosis of the disease.

Adult↗
PubMed1995

[Rest-activity and body-temperature rhythm disorders in elderly patients with dementia--senile dementia of Alzheimer's type and multi-infarct dementia].

We simultaneously monitored rest-activity and body temperature (BT) rhythm in demented patients with sleep and behavior disorders using ambulatory wrist-worn actigraph and long-term monitoring system for 5-7 consecutive days. Subjects consisted of 19 patients with senile dementia of Alzheimer's type (SDAT) (M/F = 7/12, mean age = 71.7 years), 16 patients with multi-infarct dementia (MID) (M/F = 9/7, mean age = 75.2 years) and 9 normal controls (M/F = 4/5, mean age = 70.4 years). Both dementia groups showed a significant increase in percentage of nighttime activity. In the SDAT group, a significant positive correlation between the degree of dementia and total activity was observed, but not observed in the MID group. A significant high amplitude of BT rhythm was observed in the SDAT group comparing that in the MID or the control group. These findings indicate that the SDAT patients had a disrupted rest-activity rhythm with the severity of intellectual deterioration and increased night activity, while the circadian BT rhythm was remarkably well preserved, i.e. there was a dissociation between rest-activity and BT rhythms in the SDAT group. On the other hand, the disruption of the rest-activity and BT rhythm in the MID patients was characterized by a concomitant decrease of amplitude, which seems to have no relation with the severity of dementia. Different mechanisms could be involved in characteristic disruption of the circadian rhythms in the 2 dementia groups.

Aged↗
PubMed1995

The Comprehensive Assessment List for Affective Disorders (COALA): a polydiagnostic, comprehensive, and serial semistructured interview system for affective and related disorders.

This supplement describes the development and structure of the Comprehensive Assessment List of Affective Disorders (COALA) system, which was recently developed for a collaborative follow-up study of a broad spectrum of affective disorders in Japan and which consists of a series of semistructured interviews for affective and related disorders. The COALA distinguishes itself from the extant semistructured interviews by being able to provide polydiagnostic, comprehensive and serial assessments. It is polydiagnostic because it derives diagnoses according to 29 historical and modern diagnostic systems through computer algorithms. It is comprehensive because it not only depicts the symptoms profile and rates their severity according to various endogenicity indices and severity rating scales but also measures, in the psychosocial domain, the life events and their characteristics. In addition, it has sections for past illnesses and family history. It is serial because the system includes follow-up semistructured interviews that can be administered monthly and that monitor changes in the psychopathological and psychosocial features. The theoretical underpinnings of the COALA system, especially its polydiagnostic approach to a broad spectrum of affective disorders and its treatment of psychosocial factors, are discussed in view of recent proposals for the future nosological research. The findings of the interrater reliability study (n = 107) are also presented, with satisfactory to excellent results for almost all of the psychopathological and psychosocial variables, all of the composite severity ratings and most of the polydiagnostic evaluations.

Female↗
PubMed1992

[Effects of magnesium sulfate on brain damage by complete global brain ischemia].

The efficacy of magnesium sulfate in preventing ischemic brain damage was evaluated in 36 adult mongrel dogs subjected to an 18 min period of complete global brain ischemia. Twenty-four of 36 dogs were divided into two groups; no-therapy group (n = 12) and magnesium-treated group (n = 12). The infusion of magnesium sulfate 2.5 mmol.kg-1 was started immediately with reperfusion over 48h. In each group, acute study I and chronic study were done. In the acute study I, there were no differences between two groups in hemodynamic parameters and intracranial pressure, but delayed post-ischemic hypoperfusion was significantly improved in magnesium-treated group. In the chronic study, the neurologic outcome, which was evaluated up to 7 days after ischemia, was significantly better in magnesium-treated group than in no-therapy group. In acute study II, residual 12 dogs were divided into two groups; magnesium-administered without ischemia group (n = 6) and magnesium-administered after ischemia group (n = 6). In the acute study II, magnesium significantly crossed the blood-brain barrier into cerebrospinal fluid in magnesium-administered after ischemia group, but not in magnesium-administered without ischemia group. Magnesium might improve the neurologic outcome due to its broad and no-specific calcium entry blocking properties rather than the improvement of the delayed post-ischemic hypoperfusion. These results suggest that magnesium therapy is very useful for cerebral resuscitation after cardiac arrest.

Animals↗
PubMed1991

Multi-center study of seasonal affective disorders in Japan. A preliminary report.

A multi-center study on seasonal affective disorder (SAD) was conducted from the autumn of 1988 to the spring of 1989 with the cooperation of 16 facilities in Japan. Forty-six SAD patients were identified among 1104 respondents to our advertisements in mass media, or patients seen at the outpatient clinics. Essentially similar findings to other previous reports were obtained in terms of onset age of the first episode, duration of episode, high proportion of depression in first-degree relatives and atypical vegetative symptoms. However, a nearly equal sex ratio, together with a high proportion of unipolar depression, is characteristic of the present study. Increased appetite and carbohydrate craving were predominant only in female patients, whereas hypersomnia was prominent in both sexes. Effective response to light therapy was found in 17 SAD patients. However, a controlled study on a large number of patients is required to allow final conclusions on the efficacy of light therapy in Japanese SAD patients.

Adolescent↗
PubMed1991

Atypical depressive symptoms possibly predict responsiveness to phototherapy in seasonal affective disorder.

Phototherapy was administered to 24 depressed patients with seasonal affective disorder (SAD), of which 62%, 24%, and 14%, respectively, showed improvements of greater than or equal to 50%, 25-50%, and less than 25% based on the Hamilton rating scale for depression for SAD (HAMSAD). No patients showed aggravation or side effects. Although the improvement rate in HAMSAD correlated significantly with the pretreatment severity of atypical symptoms of depression, it did not correlate with that of typical symptoms. This suggests that phototherapy is a useful treatment in SAD and that responsiveness to phototherapy in SAD can possibly be predicted by the atypical depressive symptoms before treatment.

Adolescent↗
PubMed1991

Circadian rhythm disorders in sleep-waking and body temperature in elderly patients with dementia and their treatment.

Circadian rhythms in elderly patients with severe dementia and behavioral disorders such as wandering, agitation and/or delirium were examined. The subjects consisted of 24 patients with dementia (5 with senile dementia of Alzheimer's type and 19 with multi-infarct dementia), aged 56-89 (means = 75.5 +/- 8.7) and 8 control patients without dementia or with dementia of slight degree, aged 65-81 (means = 75 +/- 5.4). The sleep-wake state of the patients was judged every hour by nurses over periods of 1-4 mo and recorded in the form of a sleep diary. Oral temperature was recorded for 4-7 consecutive days. For the treatment of sleep-wake rhythm disorders, social interaction with nurses was encouraged in addition to drug therapy. The patients showed various types of sleep-wake disorders such as reversed day-night rhythm or irregular sleep-wake rhythm corresponding to a decreased amplitude of the sleep-wake rhythm. Circadian rhythm of oral temperature was irregularly disturbed in 59.0% of the patients in the dementia group and in only 12.5% of the patients in the control group. The effects of treatment by enforcement of social interaction with nurses was effective in reducing behavioral problems and sleep-wake rhythm disorder in 30.0% of the patients tested. However, body temperature rhythm disorganization remained after the treatment. These observations indicate that behavioral disorders such as delirium, agitation or wandering in patients with severe dementia might be closely related to disrupted biological rhythms of sleep-waking and the autonomic system (body temperature).

Aged↗
PubMed1991

Effects of 1 alpha, 25-dihydroxyvitamin D3-26,23-lactone and its intermediate metabolites on bone metabolism in vivo and in vitro.

Which intermediate metabolite of 23(S)25(R)-1 alpha,25-(OH)2D3-26,23-lactone causes the unique biological functions of 1 alpha,25-(OH)2D3-26,23-lactone different from that of 1 alpha,25-(OH)2D3 was examined comparatively. The three intermediate metabolites, 1 alpha,25(R)26-(OH)3D3, 1 alpha,23(S)25(R)26-(OH)4D3, and 23(S)25(R)-1 alpha,25-(OH)2D3-26,23-lactol stimulated bone resorption, as 1 alpha,25-(OH)2D3 did, in vitamin D-deficient rats. On the other hand, 1 alpha,25-(OH)2D3-26,23-lactone only inhibited bone resorption. 1 alpha,25-(OH)2D3, 1 alpha,25-(OH)2D3-26,23-lactone and the other three metabolites stimulated MNC formation from hematopoietic blast cells in a manner correlated with their binding affinities for the 1 alpha,25-(OH)2D3 receptor. However, CM obtained from 1 alpha,25-(OH)2D3-26,23-lactone-treated MC3T3-E1 cells inhibited MNC formation, probably by the action of some inhibitory factors elaborated by the cells treated with 1 alpha,25-(OH)2D3-26,23-lactone, whereas CM obtained from 1 alpha,25-(OH)2D3 or other metabolite-treated MC3T3-E1 cells stimulated MNC formation. These facts indicate that only 1 alpha,25-(OH)2D3-26,23-lactone has an inhibitory action of bone resorption and that the lactone ring plays a major part in its expression.

Animals↗
PubMed1991

Mouse osteoblastic cells (MC3T3-E1) at different stages of differentiation have opposite effects on osteoclastic cell formation.

Using our new culture system for multinucleate cells (MNCs) that have many characteristics of osteoclasts, we examined the effects of factors produced by osteoblastic cells on osteoclastic cell formation. Conditioned medium (CM) from undifferentiated osteoblastic MC3T3-E1 cells during their growth phase inhibited MNC formation in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. Diluted CM (1:81) from differentiated cells obtained after cultivation for more than 20 days stimulated MNC formation, but at lower dilutions inhibited their formation. Dialyzed CM (greater than 2000 mol wt) from the differentiated cells was more stimulatory than undialyzed CM and showed no inhibitory effect on MNC formation. The inhibitory effect was observed with filtered (less than 3000 mol wt) CMs and was specific for osteoblastic cell CM. Prostaglandin E2 (PGE2) was detected in the CM from undifferentiated or differentiated MC3T3-E1 cells at concentrations (317 +/- 66 and 1287 +/- 179 pg/ml, respectively) sufficient to inhibit MNC formation, and this inhibition was partially abolished with CM (at 3-fold dilution) in indomethacin-treated cells (PGE2, less than 20 pg/ml), suggesting PGE2-mediated inhibition of MNC formation and the presence of another factor(s) besides PGE2 that influenced MNC formation. In contrast to day 3 CM plus 1,25-(OH)2D3, day 60 CM plus 1,25-(OH)2D3 induced MNC formation even in the absence of GM-CSF, and this induction was inhibited by an antibody to GM-CSF. Secondary colony formation assays showed the presence of a GM-CSF-like factor in the day 60 CM. These findings indicate that osteoblastic cells are involved in the process of osteoclastic cell formation, with at least two soluble factors produced by osteoblasts, a GM-CSF-like factor, which is stimulatory, and PGE2, which is inhibitory. The effects of CMs also differed depending on the stage of osteoblast differentiation.

Animals↗