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Biomedical subjects

F Ikuta

Publications and source records attributed to F Ikuta.

At least 37 records · Page 2Linked to original sources
PubMed1995

Clear cell variants of intracranial tumors: meningioma and ependymoma.

We report two cases of rare histological types of intracranial clear cell tumor. Case 1: The tumor, on the left frontal convexity in a 64-year-old woman, consisted largely of polygonal cells with clear cytoplasm which were divided into lobules of uneven size by abundant fibrous connective tissue. Most of the tumor cells were immunopositive for epithelial membrane antigen and vimentin. Ultrastructurally, the tumor cells showed conspicuous interdigitations of their plasma membranes with frequent junctional complexes, and contained numerous glycogen granules in the cytoplasm and its processes. Occasionally, amianthoid collagen fibers were found in the fibrous stroma. Our diagnosis of this tumor was clear cell meningioma. Case 2: The tumor, in the right cerebellar hemisphere in a 64-year-old woman, consisted of round, clear cells with a honeycomb-like pattern. The tumor cells were positive for glial fibrillary acidic protein, vimentin and S-100 protein. Ultrastructurally, the tumor was composed of round cells arranged in a cell-to-cell pattern, and the adjacent cells often formed microrosettes containing microvilli in their lumina. There were scattered cells with accumulatios of glycogen granules in their cytoplasm. Our diagnosis of this tumor was clear cell ependymoma. From the light microscopic features of these tumors, it does not necessarily seem easy to discriminate them from other intracranial tumors composed of similar clear cells, such as oligodendroglioma, central neurocytoma, hemangioblastoma and metastic renal cell carcinoma. Ultrastructural examination is crucial in the identification of the clear cell variants of meningioma and ependymoma.

Brain Neoplasms↗
PubMed1994

Occurrence of GD3 ganglioside in reactive astrocytes--an immunocytochemical study in the rat brain.

Immunocytochemical study of ganglioside GD3 (II3 alpha(NeuAc alpha 2-8NeuAc)-LacCer) was performed in the cold lesions produced in the cerebral cortex of the rat brain, using mouse IgM anti-GD3 monoclonal antibody (DSG-1). Seven and 15 days after cold lesioning, GD3-like immunoreactivity was observed in reactive astrocytes. Thirty and 50 days after cold lesioning, GD3-like immunoreactivity was observed in the cells that formed glial scars. Normal astrocytes were not immunoreactive. Therefore, it is possible that GD3 may play an important role in the astrocytic functions required for the process of repair of edematous lesions in the central nervous system.

Animals↗
PubMed1994

A novel mutation in Cu/Zn superoxide dismutase gene in Japanese familial amyotrophic lateral sclerosis.

Recently, several missense mutations in the Cu/Zn superoxide dismutase gene (SOD1) have been reported as a putative cause of chromosome-21q-linked familial amyotrophic lateral sclerosis (FALS). We have discovered a novel missense mutation (substitution of Thr for Ala4) in exon 1 (GCC to ACC) in two FALS patients from one Japanese FALS family. No mutations were found in 17 cases of sporadic ALS. The enzyme activity of recombinant fusion protein containing the Cu/Zn superoxide dismutase (SOD) with the Ala4-to-Thr mutation was significantly reduced in E. coli. On the other hand, in the expression system in insect cells using Baculovirus, the mutant SOD expressed an enzyme activity as high as wild-type SOD. These results suggest that the stability of SOD with the Ala4-to-Thr mutation is disrupted especially in the fusion protein. Autopsy was carried out on one of the two patients, and the pathological findings were typical of FALS with posterior column involvement. These results raise the possibility that mutation of the SOD1 is responsible for FALS with broader pathological involvement.

Amino Acid Sequence↗
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

Motor neuron disease with multi-system involvement presenting as tetraparesis, ophthalmoplegia and sensori-autonomic dysfunction.

We carried out a postmortem examination on two Japanese patients, 64- and 80-year-old men whose survival was prolonged with an artificial respirator. They had no family history of neuropsychiatric disorders and were suspected, clinically, as having a motor neuron disease that differed from amyotrophic lateral sclerosis (ALS). As well as upper and lower motor neuron impairment, they showed a variety of symptoms, such as sensory disturbances, hypohidrosis, impotence, ophthalmoparesis and/or atonic neurogenic bladder, and their protein content in cerebrospinal fluid was elevated markedly. Pathological examination revealed the following extensive nervous system involvement: (1) the upper and lower voluntary motor systems, including the IIIrd, IVth and VIth cranial nerve nuclei: (2) the reticular formation and its major afferent pathways; (3) the vestibulospinal and tectospinal systems; (4) the spinocerebellar system and the exteroceptive somatic afferent pathways; (5) the dentatorubral and pallidoluysian systems; and (6) the substantia nigra, locus ceruleus and intermediolateral and Onufrowicz's nuclei. Neither Bunina bodies, Lewy body-like hyaline inclusions nor ubiquitin immunoreactive skein-like structures were observed. The distribution of the lesions was quite different from that in patients with ALS and the other known related diseases. Recently, seven autopsied cases with clinical and histopathological similarities to our patients have been reported in Japan. Our conclusion is that our two and these seven patients should be classified as having a new motor neuron disease entity, which can be is differentiated from ALS.

Aged↗
PubMed1994

The neostriatum and nucleus accumbens in parkinsonism-dementia complex of Guam: a pathological comparison with Alzheimer's disease and progressive supranuclear palsy.

The neostriatum, nucleus accumbens and basal nucleus of Meynert (bnM) in the parkinsonism-dementia complex of Guam (Guam PDC) were examined immunohistologically, ultrastructurally, quantitatively and topographically, and the results were compared with those in Alzheimer's disease (AD) and progressive supranuclear palsy (PSP). Compared to neurologically normal controls, the number of large neurons in Guam PDC was reduced by approximately 70% in the caudate nucleus and putamen and by more than 90% in the nucleus accumbens. The decreased number of large neurons in the neostriatum was significantly correlated to that in the bnM. The remaining large neurons and many of the medium-sized neurons in the neostriatum and nucleus accumbens were immunopositive for tau protein and contained varying amounts of 21- to 25-nm-wide paired helical filaments (PHFs) admixed with straight tubules. Curly fibers and circularly arranged reactive astrocytes were seen in the nucleus accumbens of many PDC patients. Collectively, these findings, which are similar in part to those of AD and differ from those of PSP, suggest that the large neurons in the neostriatum and nucleus accumbens in Guam PDC degenerate through PHF formation, and that extremely severe loss of large neurons in the nucleus accumbens may be linked to marked degeneration of the limbic and ventral tegmental areas and nucleus dorsal raphe.

Adult↗
PubMed1994

Familial amyotrophic lateral sclerosis with a mutation in the Cu/Zn superoxide dismutase gene.

Several missense mutations within exons 1, 2, 4 and 5 of the gene for Cu/Zn-binding superoxide dismutase (SOD1) have been discovered to be involved in the development of chromosome 21q-linked familial amyotrophic lateral sclerosis (FALS). We describe here an autopsied patient with FALS, in whom we have recently identified a novel missense mutation in exon 1 of the SOD1 gene. The neuropathological findings were compatible with those described previously in patients with FALS with posterior column involvement. This suggests that mutations of the SOD1 gene may be responsible for this form of FALS.

Adult↗
PubMed1994

Amyotrophic lateral sclerosis of Guam: the nature of the neuropathological findings.

To elucidate the fundamental differences and similarities of the neuropathological features and etiopathogenesis of the amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex (PDC) of Guam, we conducted a topographic, quantitative and histological investigation of tau-containing neurons, neurofibrillary tangles (NFTs), Bunina bodies and ubiquitinated inclusion bodies in 27 non-ALS non-PDC Guamanian subjects, as well as 10 Guam ALS patients, 28 PDC patients, and 5 patients with combined ALS and PDC (ALS-PDC). The topographic distribution of NFTs was basically the same in each disease and also in the non-ALS non-PDC group. There were relatively few, if any, NFTs in non-ALS non-PDC subjects and ALS patients, but there were many, especially in the frontal and temporal cortex, in Guam PDC and ALS-PDC patients. The histological and ultrastructural features of Bunina bodies in Guam ALS and ALS-PDC patients were similar to those reported in classic ALS. The ratio of occurrence of the inclusion in Guam ALS and ALS-PDC patients was similar to that reported so far in classic ALS. Ubiquitinated skein-like inclusion bodies were observed in the spinal anterior horn cells in Guam ALS and ALS-PDC patients. These findings indicate that classic ALS does exist on Guam, that NFTs in Guam ALS patients are merely a background feature widely dispersed in the population, that the mechanism of neuronal degeneration of Guam ALS is basically different from that of PDC, and that Guam ALS occurs initially are classic ALS.

Adult↗
PubMed1994

Metastatic pineocytoma of the spinal cord after long-term dormancy.

An unusual tumor in the spinal cord of a 57 year old man is reported. At the age of 42 years, the patient had had a pineal region tumor that subsequently disappeared completely after local radiation therapy only. Eleven and 15 years later, at the ages of 53 and 57 years, respectively, solitary spinal cord tumors were found and removed. Pathological examination revealed that these tumors were of neurogenic origin and showed the characteristic features of pineal parenchymal tumors such as pineocytoma and pineoblastoma. Based on the cytology of individual tumor cells and the absence of mitotic figures and necrotic foci, this patient was diagnosed as having metastatic pineocytoma of the spinal cord. This case suggests that distant, subarachnoidal metastasis to the spinal cord can occur in pineocytomas even after long-term dormancy.

Brain Neoplasms↗
PubMed1994

Familial juvenile parkinsonism: clinical and pathologic study in a family.

We describe a family with juvenile-onset parkinsonism, which improved following sleep. Four of the five siblings in this family developed a similar onset of parkinsonism at an early age, and the parents were first cousins. In one of the siblings, a 67-year-old woman, pathologic changes at autopsy were confined to the substantia nigra pars compacta (SNPC) and locus ceruleus. The SNPC revealed obvious neuronal loss and gliosis in the medial and ventrolateral regions. In the remainder of the SNPC and the locus ceruleus, the population of neurons was reduced and there was low melanin content in most of the neurons but no detectable gliosis or extraneuronal free melanin pigment suggestive of a neurodegenerative process. There were no Lewy bodies. The entire pathologic picture was different from that of Lewy body Parkinson's disease.

Adult↗
PubMed1994

Topographic investigation of brain atrophy in parkinsonism-dementia complex of Guam: a comparison with Alzheimer's disease and progressive supranuclear palsy.

The topographic distribution of brain atrophy in nine patients with parkinsonism-dementia complex of Guam (Guam PDC) was evaluated quantitatively, and compared with that in six Japanese patients with Alzheimer's disease or senile dementia of Alzheimer type (AD), five Japanese patients with progressive supranuclear palsy (PSP), and nine Japanese control subjects. Characteristic features of Guam PDC were as follows: (1) severe atrophy of the frontal and temporal cortex with relative preservation of the white matter; (2) atrophy of the tectum, tegmentum and cerebral peduncle of the midbrain, and (3) atrophy of the tegmentum and base of the upper pons. In contrast, sectional areas of the tectum and cerebral peduncle of the midbrain were relatively well preserved in PSP, while in AD there was no significant atrophy in the brain stem.

Aged↗
PubMed1993

Widespread multiple system degeneration in a patient with familial amyotrophic lateral sclerosis.

We report a 57-year-old woman with familial amyotrophic lateral sclerosis (ALS) with posterior column involvement of 11 years duration. The patient had been on a respirator for more than 5 years before death. In addition to the well established pathology of this form of familial ALS, there were obvious degenerative changes in the brainstem tegmentum, including the reticular formation, cerebellar cortex, dentate and red nuclei, thalamus and mammillary body. Of great interest in this case was intracytoplasmic accumulation of neurofilaments in the remaining neurons in these areas, some of which, for instance, those in the oculomotor and abducens nuclei, still showed only minimal loss. This patient had survived considerably beyond the point of respiratory failure, which is the final stage in the natural history of the disease. We considered that in this patient the underlying degenerative process of the disease had become manifested in wider areas than recognized previously during the prolonged clinical course due to respiratory support. However, whether or not such widespread degeneration would occur in all patients with this disease who survive longer with the help of respiratory support awaits further studies.

Amyotrophic Lateral Sclerosis↗
PubMed1993

Novel eosinophilic intracytoplasmic inclusions in a meningioma.

BACKGROUND: Two forms of inclusion, extracellular and intracytoplasmic, have been reported in meningiomas. The authors recently encountered a case of meningothelial meningioma with unusual round eosinophilic intracytoplasmic inclusions. METHODS: Ultrastructural and immunohistochemical studies were performed on the surgically removed tissue. RESULTS: Ultrastructurally, the inclusions were found in the cytoplasm and processes of the tumor cells. Each inclusion consisted of a dense central mass of filaments with a looser, less dense periphery of radiating filaments. At the periphery, crystalloid lamellar structures and granules were intermingled frequently. No limiting membrane was observed. Immunohistochemically, the inclusions were unreactive for five classes of intermediate filaments, actin, ubiquitin, and amyloid. CONCLUSION: The intracytoplasmic inclusions were ultrastructurally distinct from those reported previously. The molecular aspect of these novel eosinophilic intracytoplasmic inclusions remained uncertain.

Biomarkers↗
PubMed1993

Specific expression of inositol 1,4,5-trisphosphate 3-kinase in dendritic spines.

Ultrastructural localization of inositol 1,4,5-trisphosphate 3-kinase (IP3K) in the rat cerebral cortex and hippocampus was studied immunohistochemically. In both regions, the major structure expressing a high level of IP3K was the dendritic spines of pyramidal neurons, where immunoreactivity was associated with the spine apparatuses and plasmalemma. The postsynaptic densities showed the most intense labelling. Taking into account the results of our previous observations, which demonstrated the restricted localization of the enzyme in the dendritic spines of Purkinje and basket cells in cerebellum, IP3K may be localized specifically in dendritic spines in various regions of the central nervous system, and involved in synaptic signal transduction at the spines.

Animals↗
PubMed1993

Developmental profile of inositol 1,4,5-trisphosphate 3-kinase in rat cerebellar cortex: light and electron microscopic immunohistochemical studies.

Developmental expression and intracellular distribution of inositol 1,4,5-trisphosphate 3-kinase in the rat cerebellar cortex were studied immunohistochemically. Immunoreactivity appeared first at postnatal day 1 in the rostral region of the cerebellum and by day 15 had extended throughout the whole cerebellum, being localized in the Purkinje cell layer. Shortly after the expression of the enzyme in each Purkinje cell, the labelling showed a tendency to accumulate in the dendrites in a fine granular pattern. Electron microscopy revealed that immunoreactivity was present in the Purkinje dendritic trunks with accentuation in the distal segments during the early postnatal period, thereafter becoming concentrated in the dendritic spines at later developmental stages. Labelling was associated mainly with the plasmalemma, including the postsynaptic densities and open coated vesicles, and the subplasmalemmal vesicles of the smooth endoplasmic reticulum. Immunoreactivity was also evident in the perisomatic processes of immature Purkinje cells, which are transient projections synapsing with climbing fibers. In developing Purkinje axons, immunoreactivity was accentuated in the distal segments, associated with the plasmalemma and synaptic vesicles. These results suggest that inositol 1,4,5-trisphosphate 3-kinase is involved in the dendritic arborization and subsequent spine synaptogenesis of Purkinje cells, and that the developing presynaptic nerve endings of these cells are another functional site for the enzyme.

Aging↗
PubMed1993

Association of IgG anti-GD1a antibody with severe Guillain-Barré syndrome.

We earlier reported cases of 2 patients with severe acute Guillain-Barré syndrome (GBS) associated with high-IgG anti-GD1a antibody titer. We now have investigated the autoantibody against GD1a or GM1 in 37 GBS patients using the enzyme-linked immunosorbent assay and have found a statistically significant association between IgG anti-GD1a antibody and the severity of the disease (need of a respirator for more than 1 month and a poor functional prognosis 3 months after neurologic onset). An autopsy which showed severe GBS associated with IgG anti-GD1a antibody produced the following findings: (1) severe axonal degeneration and segmental demyelination of peripheral nerves; (2) lymphocytic infiltration; and (3) marked central chromatolysis of the lower motoneurons.

Adolescent↗
PubMed1993

A quantitative pathological investigation of the cervical cord, roots and ganglia after long-term amputation of the unilateral upper arm.

A pathological study was conducted on an autopsied patient who had undergone amputation of the right arm at the level of the shoulder 38 years prior to death. The numbers of anterior horn cell, spinal ganglion cells and myelinated fibers in the anterior and posterior spinal roots at the cervical segments were examined quantitatively and compared with those of age-matched control subjects. On the amputation side, anterior horn cells, spinal ganglion cells and large myelinated fibers of the anterior and posterior roots were decreased in number. In addition, on the spared side, the medium-sized neurons of Rexed's lamina IX were shrunken, or decreased in number, and the number of small- and medium-sized myelinated fibers in the anterior roots was decreased. These findings indicate that the long-term effects of axonal amputation induce retrograde degeneration of the anterior horn and spinal ganglion cells on the amputation side, resulting in atrophy and a decrease of medium-sized neurons in the anterior horn even on the contralateral, spared side.

Amputation, Traumatic↗