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Manabu Ikeda

Publications and source records attributed to Manabu Ikeda.

35 records · Page 2Linked to original sources

Heterogeneity of cerebral blood flow in frontotemporal lobar degeneration and Alzheimer's disease.

This study was designed to quantify the heterogeneity on cerebral blood flow single-photon emission tomography (SPET) images in frontotemporal lobar degeneration (FTLD) and Alzheimer's disease (AD) using a three-dimensional fractal analysis. Twenty-one FTLD patients, 21 AD patients and 11 healthy controls underwent technetium-99m hexamethylpropylene amine oxime SPET scanning. Patients with FTLD and AD matched for sex, age and the severity of dementia as estimated with the Clinical Dementia Rating and were determined to be in the early stage of illness. We delineated the SPET images using a 35% cut-off and a 50% cut-off of the maximal voxel radioactivity and measured the number of voxels included in the contours of two different cut-offs. The fractal dimension (FD) was calculated by relating the logarithms of the cut-offs and the numbers of voxels, and it was defined as the heterogeneity of the cerebral perfusion. We divided the SPET images into two sets, anterior and posterior, with equal numbers of coronal SPET slices. We calculated total FD, anterior FD and posterior FD for total, anterior and posterior SPET images. Anterior FDs for FTLD and AD were 1.55 +/- 0.34 and 1.24 +/- 0.19 (P = 0.0002). The ratios of anterior to posterior FD for FTLD and AD were 1.81 +/- 0.41 and 1.32 +/- 0.14 (P < 0.0001). Use of the anterior FD and the ratio of anterior to posterior FD separated FTLD patients from AD patients and controls with a sensitivity of 85.7% and a specificity of 93.8%. Anterior FD and the ratio of anterior to posterior FD may be useful in distinguishing FTLD from AD.

Aged↗

Epidemiology of frontotemporal lobar degeneration.

A few epidemiologic studies have dealt with the prevalence of frontotemporal lobar degeneration (FTLD), including Pick's disease. The aim of this study was to review the epidemiologic studies of FTLD in western countries and to compare them with those in Japan. A community-based study of early-onset dementia in London revealed that 12% of cases with frontotemporal dementia (FTD) fulfilled the Lund-Manchester criteria in contrast to 34% of cases with Alzheimer's disease (AD) in a sample of 185 cases. The Cambridge Group has recently examined the prevalence of early-onset dementia in a community-based study. Of 108 cases, 15.7% had FTLD and 25% had AD. FTLD included 13 FTD cases, and 2 each with semantic dementia (SD) and nonfluent progressive aphasia (PA). Almost one third of cases with FTLD (29%) had a positive family history. Of our consecutive 330 outpatients with dementia (hospital setting without age limitation), 42 (12.7%) had FTLD and 215 (65.1%) had AD. In our series of patients, 22 FTD, 15 SD and 5 PA cases were identified. There was no family history in all subtypes of FTLD. Epidemiologic studies, both community-based and hospital-based, demonstrate that FTLD is a more common cause of early-onset dementia than previously recognized. Regarding the subtypes of FTLD, in Japan, compared with the data from the UK, FTD is less common, SD may be more common and PA is equally common. The reason for this discrepancy is supposed to be mainly based on the role of heredity.

Age Distribution↗

[Pick complex].

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Basal Ganglia↗

Delusions of Japanese patients with Alzheimer's disease.

BACKGROUND: Delusions constitute one of the most prominent psychiatric complications in Alzheimer's disease (AD). However, there is little consensus of the prevalence and associated factors for delusions in AD. AIMS: To reveal the characteristics of delusions among Japanese patients with AD. METHOD: 112 consecutive patients with AD were recruited over a one year period and administered the Neuropsychiatric Inventory (NPI). RESULTS: Delusions were present in 53 patients (47.3%). Delusions of theft were the most common type of delusion (75.5% of patients with delusions), followed by misidentification delusions and delusions of suspicion. More hallucination, agitation, and female gender were found in the delusions group. CONCLUSIONS: The authors found a high frequency of delusions, particularly of delusions of theft and suggested that gender was associated with the expression of delusions in Japanese patients with AD.

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Surface dyslexia in a Japanese patient with semantic dementia: evidence for similarity-based orthography-to-phonology translation.

We studied the reading performance of a Japanese-speaking patient, TI, with bilateral but asymmetrical (left more than right) temporal-lobe atrophy, severe anomia, and poor word comprehension. Most Japanese kanji characters correspond to several different legitimate pronunciations in different contexts, with varying degrees of correspondence consistency. TI made many errors in reading aloud words that violate statistically typical character-sound correspondences, especially for less common words, but had relatively preserved ability to read aloud strings in which the assignment of the typical pronunciation for each component character yields the correct pronunciation for the whole word. The degree of consistency of character-sound correspondences affected his performance on both words and nonwords in a graded manner. One interpretation is that TI's surface dyslexic reading reflects intact direct computation of phonology from orthography, but without the additional constraint from word meaning that is, in this framework, considered critical for correct pronunciation of lower-frequency words with atypical character-sound correspondences. Another interpretation is that TI's performance reflects partially damaged lexical knowledge of whole-word orthography and phonology, coupled with spared sublexcal knowledge of character-sound correspondence rules. Whichever of these interpretations is preferred, this study offers the most detailed information yet available on the characteristics of surface dyslexia in Japanese.

Dementia↗

Delayed-type hypersensitivity in sheep induced by synthetic peptides of bovine leukemia virus encapsulated in mannan-coated liposome.

Four sheep were immunized with synthesized peptides, derived from bovine leukemia virus (BLV) envelope glycoprotein, encapsulated in mannan coated liposomes as adjuvant. On the seventh day after the immunization, the sheep were intradermally challenged with BLV antigen, or synthesized peptides. The areas challenged with antigen were increased skin thickness and biopsied sequentially for immunohistological examinations. Strong delayed-type hypersensitivity was induced in sheep immunized and challenged with peptides encapsulated in mannan-coated liposomes. The major phenotype of the infiltrating lymphocytes was CD5(+). The ratio of CD4(+) to CD8(+) cells was about 1:1.

Adjuvants, Immunologic↗

Relation between phenotype of tumor cells and clinicopathology in bovine leukosis.

Thirty-three cases of enzootic bovine leukosis (EBL) and 14 cases of sporadic bovine leukosis (SBL) were examined by immunohistochemistry using 6 monoclonal antibodies against leukocyte differentiation molecules of bovine leukocytes. There were 17 cases of B-1a cell type, 10 cases of B-1b cell type and 6 cases of B-2 cell type in EBL, and 5 cases originating from B cells (B-2 cell type) and 9 cases originating from immature T cells in SBL. The average age for the EBL cases of B-1a cell type was 8.6 years, B-1b cell type was 6.5 years, and of B-2 cell type was 4.5 years. In cases of SBL, immature T cell type patients were younger than B-2 cell type ones. The lymphoma originating from B cells differed from that originating from T cells in morphology. In T cell tumors, the nucleus of tumor cells was round, the edge of the cytoplasm obvious, and tumor cells were sporadically present and proliferated. When compared with T cells, the region among B cells was obscure. But, there was no relation between phenotype and the histologic classification of tumor cells. In EBL, beyond the lymph node, tumors of B-1a and B-1b types had developed in the heart and abomasum, and those of the B-2 type tended to occur in liver. In SBL, B-2 type and T type cells formed tumors in the liver, kidney, thymus, and one case of T-cell type tumor formed on the skin. We would like to propose a new classification of bovine leukosis as EBL, calf type B-cell lymphoma, juvenile T-cell lymphoma and skin type T-cell lymphoma.

Abomasum↗

[The prevalence of mild cognitive impairment (MCI) among the community-dwelling elderly: findings from the 2nd Nakayama study].

To determine the prevalence of Mild Cognitive Impairment (MCI) in community dwelling elderly, a door to door population survey was carried out on all persons aged 65 years and older residing at home on the prevalence day (1 August 1999). All assessments were conducted by neuropsychiatrists. The diagnosis was made with the Geriatric Mental State (GMS)--Automated Geriatric Examination for Computed Assisted Taxonomy (AGECAT) (Copeland et al, 1986). AGECAT organicity levels 1 and 2 (sub-cases) are referred to as MCI. Of 1461 inhabitants, 1156 (79.1%) completed the protocol. The prevalence of MCI was 5.3%, with 1.7% organic brain syndrome level 2 and 3.6% organic brain syndrome level 1. MCI is associated with an increased risk of developing dementia. However, research on the prevalence of MCI has produced inconsistent data. The operational consensus criteria of MCI should be established for future community-based longitudinal study.

Age of Onset↗

[Cotard syndrome].

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Anti-Anxiety Agents↗

[Porphyria].

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5-Aminolevulinate Synthetase↗

The Stereotypy Rating Inventory for frontotemporal lobar degeneration.

A many behavioral disturbances, Stereotypic behaviors are among the best discriminators of Frontotemporal Lobar Degeneration (FTLD). A recent preliminary report suggests many of the behavioral symptoms, including stereotypic behaviors in FTLD patients, respond to medication with selective serotonin re-uptake inhibitors. However, there is no scale that evaluates stereotypic behaviors comprehensively. To assess the wide range of stereotypic behaviors encountered in FTLD, we developed a new instrument, the Stereotypy Rating Inventory (SRI). The SRI assesses five distinctive stereotypic behavioral disturbances often seen in patients with FTLD: eating and cooking behaviors, roaming, speaking, movements, and daily rhythm. The SRI uses the same technique as the Neuropsychiatric Inventory (NPI) in that both the frequency and the severity of each behavior are determined. The studies reported here demonstrate the content and concurrent validity, as well as inter-rater and test-retest reliability, of the instrument. Scores of FTLD patients (n=26) on the SRI were much higher than those of patients with Alzheimer's disease (n=46), patients with vascular dementia (n=26), and normal control subjects (n=40). The SRI appears to be a useful instrument for detecting stereotypic behaviors and monitoring of therapies in FTLD patients.

Aged↗

Reducing the burden of caring for Alzheimer's disease through the amelioration of "delusions of theft" by drug therapy.

BACKGROUND: Delusions of theft (delusions involving the theft of possessions) are one of the most frequent neuropsychiatric manifestations of Alzheimer's disease (AD). OBJECTIVE: The current study investigated the presence and extent of such delusions before and after drug treatment in a group of AD patients, and the consequent effects on the burden of care on caregivers. METHOD: The study was an open-label cohort design. The delusions studied consisted only of those involving theft of possessions. Sixteen AD patients served as subjects in order to assess the efficacy of Risperidone administration, in the reduction or elimination of these delusions. The caregiver burden was evaluated using the Zarit Caregiver Burden Interview (ZBI) before the administration of Risperidone and 12 weeks after administration, for cases where delusions of theft were eliminated or reduced. RESULTS: The burden of care on caregivers was significantly reduced (p < 0.001) through the elimination or reduction of delusions of theft. CONCLUSION: Delusions of theft are considered to be a major factor in increasing the burden of care, and the treatment of these, through appropriate drug therapy, is therefore of great importance in the continuation of satisfactory care in the home.

Aged↗

[A case of motor neuron disease with progressive aphasia and dementia].

We report a 71-year-old woman showing rapidly progressive non-fluent aphasia and dementia accompanied by motor neuron disease (MND). There was no family history of dementia or motor neuron disease. There was 10 months history of dysarthria and dysphagia. On examination, she showed profound difficulty in articulation. Her comprehension was impaired in that she was unable to obey three-stage command. Her written language was also impaired with phonological spelling errors, syntactic errors, and perseveration. Neuroradiological investigations showed atrophic changes and hypoperfusion of left temporal and bilateral parietal region revealed by MRI and SPECT, respectively. Her subsequent decline was rapid. It might be likely that aphasia is much more common in dementia with bulbar MND than is currently recognized because bulbar palsy might mask the language disorder.

Aged↗