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Biomedical subjects

A Homma

Publications and source records attributed to A Homma.

At least 55 records · Page 3Linked to original sources
PubMed1994

Corticobasal degeneration: etiopathological significance of the cytoskeletal alterations.

We have studied brain tissues from three patients with corticobasal degeneration (CBD) histologically, ultrastructurally and immunohistochemically. Ballooned neurons in the cerebral cortex and severe degeneration of the substantia nigra were observed in them all and weakly basophilic neurofibrillary tangles (NFTs) were distributed widely in the basal ganglia and brain stem. Ultrastructural examination demonstrated that the NFTs comprised characteristic 15-nm-wide straight tubules, which showed positive immunohistochemical staining with an antibody against tau, but not ubiquitin. Tau-immunoreactive neuronal cell bodies without NFTs also were found in the cerebral cortex and subcortical nuclei, predominantly in the brain stem, and the greatest number of tau-positive glial inclusions occurred in the cerebral gray and white matter of the pre- and post-central gyri. These inclusions comprised tubular structures with diameters of about 15 nm and were localized in the oligodendroglial cellular cytoplasm and processes. These findings indicate that there is a close cytoskeletal pathological relationship between CBD and progressive supranuclear palsy.

Aged↗
PubMed1994

The transfer of vaccine technology to developing countries. The Latin American experience.

Technological advances by developed countries are producing safer, more potent vaccines. In addition, the transfer of the technology of vaccine production to some developing countries has been taking place during the past five decades, thereby making possible the participation of developing countries in the production and supply of the essential biologicals that are required for immunization programs. Examples of successful transfers of technology, the decisive elements and factors that contribute to the transfers, and the major obstacles to such transfers are presented.

Caribbean Region↗
PubMed1994

The Cognitive Abilities Screening Instrument (CASI): a practical test for cross-cultural epidemiological studies of dementia.

The Cognitive Abilities Screening Instrument (CASI) has a score range of 0 to 100 and provides quantitative assessment on attention, concentration, orientation, short-term memory, long-term memory, language abilities, visual construction, list-generating fluency, abstraction, and judgment. Scores of the Mini-Mental State Examination, the Modified Mini-Mental State Test, and the Hasegawa Dementia Screening Scale can also be estimated from subsets of the CASI items. Pilot testing conducted in Japan and in the United States has demonstrated its cross-cultural applicability and its usefulness in screening for dementia, in monitoring disease progression, and in providing profiles of cognitive impairment. Typical administration time is 15 to 20 minutes. Record form, manual, videotape of test administration, and quizzes to qualify potential users on the administration and scoring of the CASI are available upon request.

Aged↗
PubMed1994

Opportunities and challenges in international collaborative epidemiologic research of dementia and its subtypes: studies between Japan and the U.S.

Estimates of the prevalence rates for dementia vary significantly among countries. Such variation may be explained, at least in part, by methodologic differences in studies. The disparities in prevalence rates of dementia subtypes, particularly Alzheimer's disease and multi-infarct dementia, are especially apparent in studies conducted in Eastern and Western countries. In Japan and China, the prevalence of multi-infarct dementia exceeds that of Alzheimer's disease, whereas in the West, Alzheimer's disease predominates in the vast majority of studies. Clearly, cross-cultural studies of incidence using standard methods are needed to investigate whether a true difference in risk exists, and which risk factors differentially contribute to this variation. Migrant studies of genetically homogeneous populations offer a unique opportunity to answer these questions. This article explores the value of migrant studies, their application to etiologic questions of dementia and its subtypes, and recommendations concerning how to conduct such studies.

Aged↗
PubMed1994

Relationship of behavioral complications and severity of dementia in Japanese elderly persons with dementia.

Management of behavioral symptoms in patients with age-associated dementia is essential to improve quality of life for them and their caregivers. Although many results have been reported about the burden on caregivers of demented relatives, no guidelines for managing behavioral symptoms of demented patients have been developed. One of the major reasons for the lack of practical guidelines is that dementia behavioral syndromes have been understood to be a socio-psycho-somato disorder. Also, no standardized procedures to assess behavioral symptoms are yet available. In this article, the relationship of behavioral symptoms to the severity of dementia is examined by different assessment procedures, with the aim of understanding their manifestation mechanisms. In 223 patients with age-associated dementia, including 99 with Alzheimer type dementia, 32 behavioral symptoms were assessed according to frequency, severity, and intensity, which was assessed corresponding to a value score multiplied by a frequency score multiplied by a severity score. The results by an analysis of covariance with intensity, frequency, and severity of symptoms as dependent variables; severity of dementia as an independent variable; and age, sex, and activities of daily living scores as covariates, indicated that some behavioral symptoms are significantly related to severity of dementia, which is hypothesized to correspond to organic changes in the brain, while other symptoms are not related to severity of dementia. Also, the pattern of relationship varied according to assessment procedures.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMed1994

[The effect of induction chemotherapy with CBDCA, 5-FU and UFT in head and neck cancer].

Induction chemotherapy of low-dose CBDCA, 120-hour continuous infusion 5-FU and UFT was applied to 22 patients with untreated head and neck cancer. CBDCA 75 mg/m2 was given on day 1 and, subsequently, 5-FU 1,500 mg/m2/day for 120-hour continuous infusion was started. UFT was administered every day orally at 400-600 mg/day as biochemical modulation. If tumors were reduced and side effects were mild, these schedules were repeated after two weeks. Three patients (14%) achieved a CR and 11 (50%) a PR, for an overall response rate of 64%. Anorexia, nausea, vomiting and stomatitis were the predominant toxicities. They were mild and well tolerable, although severe diarrhea was observed in one case. Good general conditions of patients were kept because of low grade of toxicities. They were important factors for the tolerance of subsequent radiotherapy and surgery. Based on these results, we conclude that the combination of low-dose CBDCA, 5-FU and UFT as biochemical modulation is effective in head and neck cancer.

Administration, Oral↗
PubMed1992

[Psychosomatic state of centenarians].

A survey to investigate the psychiatric and physical characteristics of centenarians was conducted from 1987 to 1989 in the Tokyo metropolitan area with a team of psychiatrists and psychologists using a semi-structured interview form. In that 3-three period, out of 509 centenarians living in Tokyo, 294 persons and their caregivers (57.8%) including the 65 institutionalized centenarians were examined. Two hundred and fifteen centenarians were not able to be interviewed due to various reasons. Out of 294 centenarians, 76 persons (25.9%) were interviewed by telephone. Also out of these, 176 (59.8%) were living with their son's or daughter's family. Ten male centenarians (12.8%) were living with their wives, while no female was living with a spouse. Five men and four women were living alone. There was a marked difference of education in years between both sexes. Mean years of education were 10.2 in the male and 5.5 in the female. According to the Clinical Dementia Rating, 31.6% out of 218 centenarians interviewed were not demented and those with dementia were even distribution of mild, moderate and severe dementia. There were marked differences according to sex, similar to that found in ADL. Of 63 males, 46.0% were not demented, whereas 25.8% of 155 females were not demented. Only 3.2% of males were severely demented, but in females 27.1% showed severe dementia. HDS scores decreased in relation to the advance in severity of dementia. Approximately 27% of the cases had no previous physical histories; 21.8% for the male and 29.2% for the female.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMed1992

[Assessment and treatment of patients with dementia of the Alzheimer type].

Recently more than a dozen clinical trials for dementia of the Alzheimer type (DAT) have been conducted in Japan using almost the same diagnostic criteria and assessment procedures. Cholinomimetic drugs such as AChE or M1 agonist are the most common in the current clinical drug trials. DSM-IIIR and NINCDS-ADRDA are usually employed as diagnostic criteria. In the recent report on the sensitivity and specificity of these diagnostic criteria, it has been indicated that the clinician or researcher who wishes to ensure that patients classified as DAT are more likely DAT should choose DSM-III, whereas the investigator who wishes to include the greatest number or DAT cases, seldom assigning a diagnosis of no DAT to a true case, should choose NINCDS-ADRAD. Also, development of exclusion criteria for DAT would be essential to improve interrater reliability of these diagnostic criteria. In the recent clinical trials outside Japan, a dual assessment procedure consisting of objective psychometric test(s) to assess cognitive impairment and global clinical impression of change is a standard method to evaluate the clinical efficacy of drugs for DAT. In psychometric tests, Alzheimer's Disease Assessment Scale (ADAS) is the most common in the US and Hasegawa's Dementia Scale (HDS) in Japan. A Japanese version of ADAS-cog. has been already developed for use in clinical trials in Japan. Also, HDS has recently been revised to improve the sensitivity of the test. In addition, Clinical Dementia Rating (CDR) that is one of the common measures staging severity of dementia in Japan might be a better alternative to the conventional Clinical Global Impression of Change (CGIC) in the US.(ABSTRACT TRUNCATED AT 250 WORDS)

Alzheimer Disease↗
PubMed1991

Behavioral evaluation of Alzheimer disease in clinical trials: development of the Japanese version of the GBS Scale.

GBS scale with four subscales and 26 total items is a behavior rating scale for dementia syndromes, and is now being used as one of the measures to assess the effects of drug therapy in dementia in Japan. In this article, the reliability and validity of the Japanese version of GBS Scale (GBSS-J) in 246 patients with dementia are examined. Two pairs of raters independently rated 20 patients to test inter-rater reliability of the 26 items. Pearson's correlation coefficients indicated good agreement between the raters except for nine items. The validity of the 26 items was examined by comparing them with the Functional Assessment Staging. Physical disability was evaluated by the Rapid Disability Rating Scale. Twenty items of GBSS-J measured the severity of dementia with sufficient validity. In addition, the items of eating, impaired physical activity, impaired wakefulness, and irritability were related to severity of physical disability rather than to dementia by the results from an analysis of variance and covariance. Although internal reliabilities by Cronbach's alpha of the three subscales were relatively high except for the subscale of different symptoms common in dementia, a factor analysis of the 26 items raised questions concerning the construct validity of the original four subscales.

Aged↗
PubMed1990

[Effect of ascorbic acid for periodontal ligament fibroblast of human deciduous and permanent teeth].

Ascorbic acid (AsA) plays an important role in the formation of collagen in the periodontal ligaments. However, the biochemical role of AsA on the cell metabolism of periodontal ligaments remains undeveloped. This study attempts to explore the effect of AsA and L-Ascorbic acid-2-phosphate (AsA-P) on the cell proliferation and differentiation, and the activity of cell attachment and spreading of conditioned medium (CM) prepared from human fibroblasts derived from the periodontal ligaments of deciduous teeth (HPLF-Y) and permanent teeth (HPLF) according to the explanation methods described by Saito et al. The effect of AsA and AsA-P on DNA synthesis was observed as 15 to 20 percent enhancement in comparison with that of the control for both HPLF-Y and HPLF with exception of AsA-P for HPLF at the 7 day of cell culture. The ALPase activity of HPLF-Y and HPLF at confluent phase was stimulated significantly by the presence of AsA and AsA-P. By morphological observation, the cell spreading activity of the CM of HPLF-Y exposed with AsA-P was higher than that of exposed with AsA. An induction of the cell attachment factors from HPLF-Y is enhanced intensively by the treatment of AsA-P. Therefore, AsA-P may regulate intensively the proliferation and differentiation of HPLF-Y in terms of DNA synthesis and ALPase activity including the enhanced secretion of attachment and spreading factors.

Alkaline Phosphatase↗
PubMed1989

Recent developments in gerontopsychiatric research on age-associated dementia in Japan.

In this review article, we describe the historical background of gerontopsychiatry in Japan and elucidate research studies on dementia. To date, 19 relatively large-scale epidemiological investigations on dementia have been conducted in the community. These results suggest that approximately 4-5% of the population over age 65 has dementia. Multi-infarct dementia is more prevalent than the Alzheimer's type dementia. Three hypotheses for this finding are suggested. Finally, we propose a theoretical model correlating the relationship between degree of cognitive dysfunction and caregiver's stress.

Aged↗
PubMed1989

[Reliability and validity of the Japanese version of the GBS scale].

The Japanese version of the GBS Scale (GBSS-J) was administered to 246 elderly patients with dementia in a geriatric hospital to test the inter-rater reliability and validity of the items and the subscales of the GBSS-J. The inter-rater reliability of the 26 items was tested by rating 20 patients. After the raters conferred with each other how to rate the items of the scale, the items were rated independently. Pearson's correlation coefficients indicating the agreement between the rates were as good as more than. 660 except for the items of impaired wakefulness and confusion. The validity of the 28 items was examined by comparing them with the stages of Functional Assessment Staging (FAST). Hasegawa's dementia scale (HDS) was employed as an external standard to test the items of the subscale of intellectual functions. Physical disability was checked by using the Rapid Disability Rating Scale (RDRS). Mean scores of the 20 items except for the 6 items included in the subscale of different symptoms common in dementia significantly increased as the FAST stage advanced. These results indicated that the 20 items of the GBSS-J measured the severity of dementia with sufficient validity. In addition, according to the results of analysis of variance and covariance, the items of motor insufficiency in taking food, impaired physical activity, impaired wakefulness and irritability were related to the severity of physical disability rather than that of dementia. Also, the 10 items of the subscale of intellectual functions showed significant correlations with the scores of HDS, while the item of impaired wakefulness showed a significant, although fairly low correlation.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1985

Limited in vivo susceptibility of the South American monkey -Cebus apella- to type 1 poliovirus: physical and histopathological observations after intraspinal inoculation.

Type 1 polioviruses (an attenuated strain, Sabin 1 LSc 2ab and a virulent strain, Mahoney) were inoculated intraspinally into the South American Cebus monkey Cebus apella. Neither physical symptoms nor histological changes in the central nervous system were observed after inoculation of attenuated Sabin strain. But the virulent Mahoney strain caused flaccid paralysis in two of three monkeys. In these two paralyzed monkeys, definite specific histological changes were observed with spreading of the lesions to places far from the inoculation site, i.e., the cervical cord and brain. These results suggest that Cebus apella has limited susceptibility to type 1 poliovirus.

Animals↗