Biomedical subjects

Masaya Oda

Publications and source records attributed to Masaya Oda.

68 records · Page 4Linked to original sources

PubMed2002

Difference in disease-free survival curve and regional distribution according to subtype of spinocerebellar ataxia: a study of 1,286 Japanese patients.

Expansions of trinucleotide repeats have been discovered in spinocerebellar ataxia (SCA) types 1, 2, 6, 7, 12, and 17, Machado-Joseph disease (MJD/SCA3), and dentatorubropallidoluysian atrophy (DRPLA). However, the frequency of familial SCA in Japan remains unclear. The number of trinucleotide repeats was determined for 1,286 patients. Three hundred and thirty families (523 cases) were autosomal dominant group (A), and 165 families were positive for family history but not autosomal dominant group (B), while the remaining 598 cases were the sporadic group (C). The frequency of SCA subtypes in autosomal dominant group was: 1) 5.5% for SCA1; 2) 2.4% for SCA2; 3) 27.6% for MJD/SCA3; 4) 25.5% for SCA6; 5) 0.3% for SCA17; and 6) 7.3% for DRPLA. Abnormal expansion of SCA12 was not detected. Another 31.5% of the patients in the autosomal dominant group had unknown genetic abnormalities. Within group B, SCA6 was the most prominent and within the sporadic group MJD/SCA3 and SCA6 were the most common subtypes observed. The disease-free survival curve of SCA6 was different from that of other SCAs and the mean age at onset for SCA6 was found to be later than that of the other types. Regional differences were observed in the relative rate of SCA subtypes. MJD/SCA3 appears more common in the Kanto and Kyushu districts of Japan, whereas SCA6 is most common in the Chugoku district. In order to establish an effective social welfare system for SCA patients, clinical course and regional differences in the prevalence of SCA subtypes must be taken into consideration.

Adult↗

PubMed2002

Lewy bodies in progressive supranuclear palsy.

Lewy bodies (LBs), whose major component is alpha-synuclein, are a pathological hallmark of Parkinson's disease (PD) but have rarely been reported in progressive supranuclear palsy (PSP). Whether LBs in PSP represent the aging process or the coexistence of PD remains unclear. We found LBs in 5 of 16 patients with PSP. In 4 patients LBs were distributed widely throughout the brain stem and cerebrum in a pattern similar to that in PD. In the remaining patient one LB was found in the pontine reticular formation. Semiquantitative analysis showed that neuronal loss in the locus coeruleus and the dorsal vagal nucleus was more severe in patients with LBs than in patients without LBs. Double-labeling immunohistochemical studies showed co-localization of alpha-synuclein and tau in some neurons. Our study suggests that patients who have PSP with LBs constitute a subset of patients with PSP in whom Lewy body disease is also present.

Aged↗

PubMed2002

Cortical perivascular satellitosis in intractable epilepsy; a form of cortical dysplasia?

This report describes two cases of cortical dysplasia in patients with intractable epilepsy: the first case presents a 12-year-old male with a simple partial seizure of his left arm (case 1), while the second case presents an 8-year-old female with a complex partial seizure (case 2). Magnetic resonance images showed high signal intensity on T2-weighted and fluid attenuated inversion-recovery images in the cerebral cortex of right frontal convexity in case 1 and in the medial temporal lobe and anterior amygdala in case 2. The latter lesion showed focal contrast enhancement. Light microscopy revealed perivascular clustering of small round cells accompanied by dysplastic neurons in the second to sixth layers of the cerebral cortex. The perivascular small cells had uniformly round nuclei and plump, ground-glass-like cytoplasm. These cells closely apposed each other and were adhered to the capillaries. In case 2, a ganglioglioma was also found in the amygdala. Immunohistochemistry revealed that the perivascular small cells were vimentin and focally S-100 protein positive, but were negative for glial fibrillary acid protein, synaptophysin, neurofilament protein, microtubule-associated protein 2, neuronal nuclei antigen, nestin, carbonic anhydrase II, myelin basic protein, CD68, factor VIII, cytokeratin, epithelial membrane antigen, alpha-smooth muscle actin, CD20, CD45 and CD45RO. These data suggest that this is a previously undescribed form of cortical dysplasia comprising dysplastic neurons and immature perivascular cells of possible oligodendroglial or meningothelial lineage. We suggest the term cortical perivascular satellitosis be used to describe this lesion.

Amygdala↗

PubMed2002

Dinucleotide repeat polymorphisms in the neprilysin gene are not associated with sporadic Alzheimer's disease.

In the pathological process of Alzheimer's disease (AD), deposition of amyloid beta-peptide (A beta) in the brain parenchyma plays an important role. Neprilysin (NEP), a neutral endopeptidase, degrades A beta, and it is postulated that decreased NEP activity may contribute to the development of AD by promoting the accumulation of A beta. The human NEP gene possesses four dinucleotide repeat polymorphisms, and it is possible that these polymorphisms regulate the NEP expression levels and influence the pathological cascade of AD. Therefore, we investigated the association of these polymorphisms with AD. We performed genotyping of each polymorphism in 201 Japanese sporadic AD patients and 208 Japanese controls. There were no significant differences between the AD and control groups in allele frequencies of each polymorphism. We conclude that these polymorphisms in the NEP gene do not contribute to genetic risk factors for sporadic AD.

Aged↗

PubMed2002

Oxidative stress and disturbed glutamate transport in spinal muscular atrophy.

Spinal muscular atrophy (SMA) is a hereditary motor neuron disease, and three clinical subtypes of autosomal recessive SMA, including Werdnig Hoffmann disease (type 1), have been shown to be induced by deletion within the same genes. In order to clarify the pathogenesis of motor neuron degeneration in SMA, we immunohistochemically examine the expressions of oxidative stress-related materials (oxidative products) and glutamate transporters, which can prevent glutamate neurotoxicity, in five autopsy cases of SMA type 1. Age-matched controls did not show any deposition of oxidative products in the brain. In contrast, the abnormal deposition of 4-hydroxy-2-nonenal-modified protein, a product of membrane lipid oxidation, was observed in the spinal motor neurons in three cases, although the motor neurons did not show an increase of nitrotyrosine, which was observed in adult-onset amyotrophic lateral sclerosis. In addition, the nuclei of neurons and glial cells in the precentral gyrus, thalamus or cerebellar cortex were immunoreactive for 8-hydroxy-2'-deoxyguanosine in two cases, which was one of the most commonly used markers for oxidative DNA damage. Regarding glial glutamate transporters, three of five cases of SMA type 1 showed a reduction in immunoreactivity for excitatory amino acid transporter-1 (GLAST) in the ventrolateral nucleus of the thalamus, in which there was neither neuronal loss nor gliosis in routine histochemistry. One case, having mechanical ventilation, demonstrated a reduced expression of another glial glutamate transporter (GLT-1) throughout the central nervous system. These data suggest that oxidative stress and disturbed glutamate transport can partly be involved in the motor neuron devastation and/or latent thalamic degeneration in SMA type 1.

Adolescent↗

PubMed2002

Enhanced expression of endothelial nitric oxide synthase and caveolin-1 in human cirrhosis.

BACKGROUND/AIMS: Nitric oxide is synthesized in diverse mammalian tissues by a family of calmodulin-dependent nitric oxide synthases (NOS). Caveolin, the principal structural protein in caveolae, interacts with endothelial NOS (eNOS) leading to enzyme inhibition by a reversible process modulated by Ca++ -calmodulin. The aim of the present study was to examine the localizations of eNOS and caveolin-1 at protein level in normal human liver tissue, and how the expressions are altered in cirrhotic liver. METHODS: Fresh liver specimens were obtained from hepatic surgeries. Normal portions resected from cases of carcinoma metastasized to the liver were used as control specimens, and cirrhotic portions resected from cases of hepatocellular carcinoma with hepatitis C-related cirrhosis were used as cirrhotic specimens. Anti-eNOS and anticaveolin-1 antibodies were used for immunohistochemistry and Western blotting. Immunoelectron microscopy was conducted on ultra thin sections using immunoglobulin-gold combined with silver staining. RESULTS: Immunohistochemistry revealed that both eNOS and caveolin-1 were sparsely expressed on hepatic sinusoidal lining in normal liver specimens, and these findings were confirmed by Western blot. Both immunohistochemistry and Western blotting demonstrated over-expression of eNOS and caveolin-1 in cirrhotic liver specimens. Morphometric analysis of immunogold particle labeling for eNOS and caveolin-1 was performed on immunoelectron micrographs. In normal liver tissue, hepatic stellate cells and sinusoidal endothelial cells (SEC) expressed low levels of caveolin-1, and SEC expressed a very low level of eNOS. In cirrhotic liver, both caveolin-1 and eNOS expressions were significantly increased by approximately four-fold on SEC compared to normal liver. CONCLUSION: In cirrhotic human liver, marked increase of caveolin-1 in perisinusoidal cells may promote caveolin-eNOS binding and reduce the activity of eNOS despite an increased eNOS expression, leading to impaired NO production and increased hepatic microvascular tone.

Aged↗

PubMed2002

Promyelocytic leukemia protein is redistributed during the formation of intranuclear inclusions independent of polyglutamine expansion: an immunohistochemical study on Marinesco bodies.

Marinesco bodies (MBs) are ubiquitinated intranuclear inclusions observed in nigral pigmented neurons. They increase in number during aging, and their formation is considered to represent a cellular reaction to stress, but is not always associated with neuronal degeneration. We conducted immunohistochemical studies on MBs abundant in myotonic dystrophy brains and compared their nature with that of neuronal intranuclear inclusions (NIIs) in polyglutamine diseases. First, we examined the relationship between MBs and polyglutamine proteins and demonstrated that one of the polyglutamine proteins, ataxin-3, as well as a 19S proteasomal protein, was preferentially recruited into MBs even in the absence of expanded polyglutamine. This indicates that an alternative mechanism during the formation of MBs that is not related to polyglutamine expansion or neuronal degeneration may recruit ataxin-3 into nuclear inclusions in a protein-specific manner. Secondly, we investigated the relationship between MBs and promyelocytic leukemia protein (PML), a nuclear matrix-associated protein that is normally localized to intranuclear punctate structures (PML nuclear bodies) and is known to reorganize itself in association with polyglutamine aggregation. In nigral pigmented neurons in myotonic dystrophy, spherical, hemispherical or rod-like PML-immunoreactive structures, in addition to punctate structures, were observed in their nuclei. Similar PML redistribution was also observed in nigral pigmented neurons in aged controls and cases of hepatic encephalopathy, 2 other conditions in which abundant MBs are formed. Double immunofluorescence study revealed that these PML-positive structures undergo morphological changes in association with ubiquitin accumulation during MB formation. It is therefore indicated that PML reorganization does not represent a specific nuclear event involved in the pathogenesis of polyglutamine diseases, but may commonly occur during the formation of intranuclear inclusions as a reaction against various stresses that involve the ubiquitin-proteasome pathway.

Adult↗

PubMed2002

Magnetic resonance imaging of primary spinal intramedullary lymphoma.

The authors report 2 cases of primary spinal intramedullary lymphoma and review all previously reported magnetic resonance imaging findings on this disease. The most common finding was a solid and homogeneously enhanced mass that was hyperintense on T2-weighted images, without associated syringomyelia. In a few cases, swelling of the spinal cord was minimal.

Female↗

PubMed2002

Tortuosity of the white matter medullary arterioles is related to the severity of hypertension.

BACKGROUND: The clinical implication of the tortuosity of white matter medullary arterioles has never been clarified precisely. We quantitatively investigated the relationship between such vascular tortuosity and the severity of hypertension (HT), which was graded according to the WHO classification. METHODS: Forty-seven autopsied brains with age-adjusted stages of HT were evaluated. The largest tortuosity diameter and the largest vascular diameter in the same tortuous lesion were measured by light microscopic observation at the level of the corona radiata and centrum semiovale. A maximum ratio of these diameters was calculated for each patient. RESULTS: Maximum ratios were found in almost all arterioles and were significantly increased according to the HT stages. CONCLUSIONS: Arteriolar tortuosity in the hemispheric white matter may reflect the severity of HT and be an indicator of hypertensive small vessel disease of the brain.

Adult↗

PubMed2002

[An elderly case of microscopic polyangiitis following bronchial asthma].

A 78-year-old woman who had bronchial asthma for 15 years developed dysesthesia, neuralgia, muscle weakness and atrophy in both feet and her left hand. Prednisolone (maximum dose 80 mg) was not effective, and she displayed gait disturbance. Laboratory findings showed leukocytosis (neutrophils dominant), renal dysfunction, elevation of CRP and positive P-ANCA. Biopsy revealed vasculitis, and reduced density of myelinated fibers. Although steroid pulse therapy improved neuralgia and renal dysfunction, severe disability of motor function and sensory disturbance still remained. Vasculitis syndrome following bronchial asthma indicated Churg-Strauss syndrome (CSS), while severe renal dysfunction and lack of eosinophilia were symptoms compatible with microscopic polyangiitis (MPA). The present case showed properties of both MPA and CSS.

Aged↗

PubMed2002

[Frontal atypical teratoid/rhabdoid tumor evaluated by single-photon emission computerized tomography and positron emission tomography].

A case of frontal atypical teratoid/rhabdoid tumor (AT/RT) was presented in the findings of single-photon emission computerized tomography (SPECT) using 201Tl-chloride (Tl) and 123I-metaiodobenzylguanidine (MIBG), and positron emission tomography using 18F-fluorodeoxyglucose (FDG) and (11C-methyl)-L-methionine (Met). A 16-year-old female had an episode of Jacksonian seizures one month prior to admission. CT scans showed an isodensity mass with heterogeneous enhancement in the left frontal lobe. MR images revealed a tumor with solid and cystic components and perifocal edema. SPECT demonstrated intense accumulation of Tl and MIBG in the enhancing lesion 15 min and 30 min after intravenous injection of tracers, respectively. The 6-hr delayed SPECT showed no retention of MIBG in the enhancing lesion. FDG-PET and Met-PET revealed high uptake of tracers in the enhancing lesion. Met did not accumulate in the frontal white matter, which appeared hyperintense on T2-weighted MR images. The patient underwent an uneventful extirpation of the solid mass, where Met had accumulated. Microscopically, the solid tumor contained rhabdoid cells, spindle-shaped cells resembling mesenchymal cells, and nests of small cells. The tumor cells were immunoreactive for vimentin, cytokeratin, and epithelial membrane antigen. The MIB-1 labeling index was 25%. The histological diagnosis was AT/RT. Postoperative course was uneventful. A dose of 32.4 Gy was administrated to the whole brain and a boost of 27.8 Gy to the T2-hyperintensity lesion. Five months after the radiotherapy, MRI showed neither abnormal enhancing lesions nor the T2-hyperintensity lesion. Multifarious studies using SPECT and PET are useful for differential diagnosis and for choosing optimal therapeutic strategy for this type of tumor.

3-Iodobenzylguanidine↗

PubMed2002

[Third ventricular chordoid glioma: report of a surgical case].

We reported a rare case of third ventricular chordoid glioma and reviewed the literature. A 25-year-old male presented with a two-year history of voracious appetite. Three months prior to admission, he developed progressive memory impairment. CT scan showed a well circumscribed, slightly hyperdense mass without calcification in the third ventricle. The 4.5-cm oval mass occupying the anterior part of the third ventricle was homogeniously enhanced on MR images after administration of contrast medium. Small cystic components were present in the periphery of the mass. CT-guided stereotactic biopsy was performed. Microscopically, epithelioid tumor cells were embedded in mucinous stroma containing a lympho-plasmacytic infiltration. The tumor cells were immunoreactive for GFAP and vimentin. The MIB-1-positive rate was 1.2%. The histological diagnosis was a chordoid glioma. One month after the biopsy, a right frontal craniotomy was performed to remove the tumor via the anterior transcallosal interfornitial approach. The tumor arising from the anterior part of the third ventricle wall was soft, mildly vascular and light-grayish. The tumor was completely resected. The histological findings were identical with those of the biopsy specimens. Postoperatively, the patient developed diabetes inspidus, hyperthermia, worsening memory impairment, and transient hyponatremia. The patient's symptoms gradually improved and follow-up MR images showed no evidence of recurrent tumor 17 months after the resection. Despite low-grade appearance, attachment of the tumor to the hypothalamus preclude complete resection, and this may result in tumor recurrence and less favorable prognosis in the current reports. Early detection and aggressive resection followed by stereotactic radiotherapy are important in the management of chordoid glioma.

Adult↗

PubMed2002

[An infant autopsy case of severe multicystic leukoencephalopathy].

A boy aged 4 years and 2 months died of an unknown neurological disease, which had insidiously occurred around the age of one year. The case slowly developed sleeping tendency, spastic tetraplegia, optic nerve atrophy and flexion contracture but no epileptic seizures. There was neither consanguinity nor familial history of neurological disorders. The proband had intrauterine exposure to X-ray at the seventh fetal month. Laboratory examinations including antiviral antibodies and lysosomal enzymes provided no evidence for known brain disorders. Neuropathological examination revealed widespread multicystic destruction predominantly in the centrum semiovale. The subcortical arcuate fibers were spared. The commissural fibers as well as long tract fibers were also symmetrically affected. There was neither inflammatory reaction, calcification, Rosenthal fibers nor globoid cells. Axons were comparatively preserved. Tissue debris was not metachromatic in acid cresyl violet stain. Chemical analysis demonstrated no changes in fatty acid profiles. These clinicopathological features partly mimic leukoencephalopathy with vanishing white matter (van der Knaap), except for the lack of familial history and cerebellar signs, and the more extensive neuropathological lesions. Although the influence of intrauterine X-ray irradiation could not be neglected completely, reports of several similar cases in the literature suggests that this case had a new variant of child-onset multicystic leukoencephalopathy or leukodystrophy.

Brain Diseases↗

PubMedDate not supplied

The relation between visual hallucinations and visual evoked potential in Parkinson disease.

OBJECTIVE: The pathophysiology of hallucinations in Parkinson disease is poorly understood. This study investigated the relation between visual hallucination and visual evoked potentials (VEPs) in Parkinson disease. METHODS: Nineteen patients with Parkinson disease were studied. The authors divided patients into 2 groups: patients with visual hallucinations (VH group) and those without visual hallucinations (no-VH group). VEPs using a checkerboard stimulus were recorded under a drug-free state. RESULTS: On multivariate regression analysis, only the average P100 latency was selected and remained significant after the backward elimination method. CONCLUSION: The authors demonstrated a close association between visual hallucinations and elongated VEP latency in Parkinson disease. VEPs may become one of the predictors for visual hallucination.

Aged↗