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Biomedical subjects

F Ikuta

Publications and source records attributed to F Ikuta.

At least 127 records · Page 7Linked to original sources
PubMed1988

Hereditary dentatorubral-pallidoluysian atrophy: clinical and pathologic variants in a family.

We describe a family showing dentatorubral-pallidoluysian atrophy. Three patients appeared through three successive generations and displayed a wide variety of clinical pictures. The male proband with onset in childhood showed progressive myoclonus epilepsy syndrome. The father experienced cerebellar ataxia, myoclonus, and mild dementia starting in middle age; the paternal grandmother had progressive symptoms of cerebellar ataxia, choreiform movements, and dementia, but neither myoclonus nor epilepsy in senescence. Neuropathologic examination of two patients, the proband and the paternal grandmother, revealed combined degeneration of the dentatorubral and pallidoluysian systems and obvious degeneration involving the striatum in the proband and the cerebellar cortex in the grandmother. The present study indicates that this disease can include many clinical and pathologic variants even in the same family.

Adolescent↗
PubMed1988

[Early development of cerebral blood vessels: on the relationship between cerebral histogenesis and internal vascularization].

The purpose of this study is to evaluate the morphological relevance to cerebral histogenesis and internal vascularization during early fetal development of rats. Using light and electron microscopes, fetal brains and spinal cords from embryonic day 11 (E11) to E 16 were observed with special attention to new blood vessel formation in the parenchyma. At stages of the neural groove and neural tube blood vessels were confined in the perineural mesenchyma around the matrix cell layer whose cytoarchitecture was arranged in a pseudostratified pattern and did not include the blood vessels. At the prosencephalic stage (E 13), primordium of the striatum which localized in the ventrolateral portion of the cerebral neopallium made up the migrating zone in outer most of the matrix cell layer and blood vessels firstly appeared in this area. Similarly, the blood vessels were also recognized at the ventro-lateral portion of the mesencephalon where the migrating zone was initially formed on E 13. In the cervical spinal cord, the blood vessels were initially recognized on E 12, when the migrating zone was formed at the area of anterior horn. At the early telencephalic stage during E 14-E 15, blood vessels were evenly distributed in the lateral cerebral neopallium, while the cerebral neopallium in the midline where took place later evolution than lateral neopallium was still remaining in the state of matrix cell layer only, and was also lacking the blood vessels. In this area, first appearance of the vessels was E 15 or E 16.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

[Mitochondrial angiopathy in the cerebral blood vessels of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and strokelike episodes)].

MELAS is a distinctive syndrome manifested by mitochondrial myopathy, encephalopathy, lactic acidosis, and recurrent stroke-like episodes such as seizures, alternating hemiparesis, hemianopsia, or cortical blindness. Pathologically the disorder is characterized by multiple, solitary or continuous foci of necrosis (infarct or softening), varying in size and stage, predominantly involving the bilateral cerebral cortices and to a lesser degree cerebral white matter, basal ganglia, brainstem and cereblum. The distribution of the lesions does not correspond to vascular territories, suggesting that they are not due to usual thrombotic or embolic process. The exact nature and pathogenesis of these lesions with characteristic distribution pattern remain to be elucidated. We studied systematically cerebral blood vessels from two autopsied patients with MELAS by electron microscopy. All the main cerebral arteries including anterior, middle and posterior cerebral, basilar and vertebral arteries were examined at their proximal portions at the cerebral base and at their peripheral portions at the cortical surface as well as within brain parenchyma. We found marked accumulation of mitochondria in the cell bodies of smooth muscle cells and endothelial cells and numerous smooth muscle cells showing degeneration or necrosis, sporadically or in clusters in the tunica media. These abnormalities were most prominent in the walls of pial arterioles and small arteries up to 250 mu in diameter, and less frequent and severe in the larger pial arteries and intracerebral arterioles and small arteries. These vascular changes are different from any of those described in various disorders known to involve the cerebral blood vessels and are thus characteristic to the cerebral blood vessels of MELAS. We think that these peculiar vascular changes called mitochondrial angiopathy are caused by primary mitochondrial dysfunction in the vascular smooth muscle cells and endothelial cells themselves, as is the same in the skeletal and cardiac muscles in this disease, and that they constitute the pathogenic base of the brain lesions with unusual distribution pattern and nature in MELAS.

Acidosis, Lactic↗
PubMed1987

The occurrence of catecholamine neurons in a parietal lobe ganglioglioma.

A parietal lobe ganglioglioma in a 2-year-old girl was investigated ultrastructurally and immunohistochemically, using antiserum against tyrosine hydroxylase (TH), a rate-limiting enzyme of the catecholamine (CA)-synthesizing pathway. The tumor was composed essentially of neuronal and astrocytic cells. Ultrastructurally, numerous dense core vesicles measuring between 56 nm and 136 nm (mean, 90 nm) in diameter were observed in the neuronal cytoplasm and processes. The fact that the TH immunohistochemistry revealed many positive neuronal cells in the tumor tissue was of considerable interest. The implications and possible significance of the presence of CA neurons in this ganglioglioma are discussed.

Brain Neoplasms↗
PubMed1987

Selective involvement of large neurons in the neostriatum of Alzheimer's disease and senile dementia: a morphometric investigation.

In order to evaluate the quantitative changes in the neostriatum of Alzheimer type (SDAT), sections of the caudate head (CN) and putamen (PT) from 4 AD/SDAT and 6 age-matched control cases were stained with Klüver-Barrera, and the cell body and nuclear areas of the neurons were measured by a digitizer. This study revealed a significant decrease in the number of large neurons (nuclear area; greater than 101 micron 2) and good preservation of the number of small neurons (nuclear area; less than 100 micron 2) in CN and PT of AD/SDAT.

Aged↗
PubMed1987

Paragangliomas of the craniocervical region. An immunohistochemical study on tyrosine hydroxylase.

An immunohistochemical study on tyrosine hydroxylase (TH), a rate-limiting enzyme in the catecholamine synthesizing pathway, was made on three craniocervical region paragangliomas, two of which showed metastases to the cervical lymph nodes. In all of the original tumors, the majority of tumor cells showed positive immunostaining for TH of variable intensity in their cytoplasm regardless of their cytological features such as cellular and nuclear pleomorphism. The finding suggests that most tumor cells are capable of production of catecholamines and are derived from chief cells in the normal paraganglia. In cervical lymph nodes, however, no positive immunostaining for TH was observed in metastatic tumor cells, in contrast with the findings in the original tumors. The absence of TH immunoreactivity in metastatic tumor cells appears to be noteworthy in considering their malignant potential. Application of the TH immunohistochemistry to further cases appears important for the better understanding of this neoplasm, a catecholamine-producing tumor.

Adult↗
PubMed1987

Involvement of choroid plexus in mitochondrial encephalomyopathy (MELAS).

Morphological study of the choroid plexuses of two patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) revealed an enormously increased number of mitochondria with structural abnormalities in almost all of the choroidal epithelial cells. The majority of the cells also showed loss of microvilli and collapsed or attenuated apical cytoplasmic processes with increased electron density and lysosome-like dense bodies. The blood vessels of the choroid plexus showed the features of mitochondrial angiopathy previously described in the pial arteries of the same patients. These findings are interpreted as the morphological expression of a primary biochemical defect of the mitochondrial function in the choroid plexus, and as the probable explanation for increased CSF lactate and pyruvate levels in this disease.

Adolescent↗
PubMed1987

Esthesioneuroepithelioma: a tumor of true olfactory epithelium origin. An ultrastructural and immunohistochemical study.

A case of esthesioneuroepithelioma was investigated ultrastructurally and immunohistochemically, using antibodies against neurofilament protein (NFP), glial fibrillary acidic protein (GFAP), keratin, neuron-specific enolase (NSE), S-100 protein (S-100), and tyrosine hydroxylase (TH). The tumor initially manifested as an epidural mass in the anterior cranial fossa in a 64-year-old man, and about 3 1/2 years later, autopsy further revealed extensive metastases to the lymph nodes of the neck and thoracic cavity. In the cranial and nasal cavities, the tumor was composed of fairly uniform, ill-defined cells arranged in nests which were surrounded by a fibrovascular stroma. These histological features were reproduced in the metastatic tumor nodules with frequent occurrence of tubular arrangements of the tumor cells. Ultrastructurally, two different cell types were well recognized by their characteristic morphological features, which were reminiscent of sensory neurons and sustentacular cells of the olfactory epithelium. No dense-cored secretory granules were observed in the tumor cells. Immunohistochemically, the tumor showed a variable number of cells positive for NFP, keratin, NSE and S-100. NFP was present in a relatively small number of cells, which were found diffusely in the nests. Keratin was observed in the cells mainly located at the periphery. NSE-positive cells tended to form irregular clusters in the center. A few S-100-positive cells were found, without any particular arrangement.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMed1987

Mitochondrial angiopathy in cerebral blood vessels of mitochondrial encephalomyopathy.

We studied cerebral blood vessels of two autopsied patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). All the main cerebral arteries in the proximal portion at the brain base and more distal portion at the cortical surface, as well as within the brain parenchyma were examined by electron microscopy. There was a striking increase in number of mitochondria in the smooth muscle and endothelial cells, which were most prominent in the pial arterioles and small arteries up to 250 micron in diameter and less frequent and severe in the larger pial arteries and intracerebral arterioles and small arteries. These vascular changes have not hitherto been described in MELAS, or in other disorders affecting blood vessels of the brain and other organs. It is suggested that the vascular changes are caused by primary mitochondrial dysfunction in the vascular smooth muscle and endothelial cells of the brain and that they constitute the pathogenic base of the brain lesions and their unusual distribution pattern in MELAS.

Adolescent↗
PubMed1987

Ultrastructural alterations of neuronal cells in a brain stem ganglioglioma.

A brain stem ganglioglioma in a 9-year-old female was examined ultrastructurally. The constituent neuronal (ganglion) cells displayed various ultrastructural features of neuronal degeneration including Hirano, Lafora and zebra bodies, inclusion-like aggregates of neurofilaments and large dilatations of rough endoplasmic reticulum. Although similar observations have been reported in peripheral neuronal tumors, this is the first reported occurrence in ganglioglioma, an uncommon tumor in the central nervous system. The coincidence of these alterations in the present tumor appeared to be of great interest, however, their exact etiology remained uncertain.

Brain Neoplasms↗
PubMed1987

An autopsy case of a syndrome with muscular atrophy, decreased subcutaneous fat, skin eruption and hyper gamma-globulinemia: peculiar vascular changes and muscle fiber degeneration.

This is the first autopsy case report of a syndrome with autosomal recessive inheritance, muscular atrophy, contracture, skin eruption, hyper gamma-globulinemia, decreased subcutaneous fat, mental retardation and abnormal ECG findings. Skeletal muscles showed severe, discrete, multifocal muscular fibrosis which replaced several primary fasciculi. The tongue, heart and extraocular muscles showed identical but less severe findings. In the involved muscle fasciculi, veins and venules as well as arteries and arterioles showed medial hyperplasia and luminal constriction. Degeneration of endothelial cells of arterioles and narrowing of the lumen of terminal arterioles by the debris were observed. The peripheral nerves in the muscles were relatively well preserved. The correlation and pathogenesis of these findings are discussed.

Central Nervous System↗
PubMed1987

Glial filaments in the subcutaneous tumors of mouse glioma clones differently expressing glial fibrillary acidic protein. An immunohistochemical and ultrastructural study.

Glial filaments contain vimentin and glial fibrillary acidic protein (GFAP). The question of how glial filaments change morphologically according to the expression of vimentin and/or GFAP has remained unclear. In this study, immunohistochemical and ultrastructural examinations were performed on the subcutaneously transplanted tumors of two clones (F6B3 and G10A10) derived from a mouse glioma. F6B3 tumor expressed GFAP and vimentin in large quantities. G10A10 tumor expressed plenty of vimentin but only a little of GFAP. Ultrastructurally, F6B3 tumor contained abundant cytoprocesses in most of which numerous intermediate filaments (IFs) were arranged in a parallel array. On the other hand, only a small number of the processes were seen in G10A10 tumor, which showed a few IFs arranged either randomly or sparsely in the processes. Both tumors commonly had the IFs accompanied by visible sidearms, but there was a difference in that the smooth and firm IFs were confined to part of F6B3 tumor. Thus, the comparison made between the two models presented differences in the content, arrangement and morphology of IFs, as well as in the manner of GFAP expression, suggesting correlation between these differences.

Animals↗
PubMed1987

Subarachnoid dissemination of a pituitary adenoma.

The authors present an unusual case of a pituitary adenoma that developed into intracranial and intraspinal dissemination following intracranial surgery with adjunctive radiation, and review metastasis of pituitary adenomas in the central nervous system briefly in light of other reported cases.

Adenoma↗
PubMed1987

[An autopsy case of myoclonus epilepsy associated with ragged-red fibers (Fukuhara disease)].

In 1980, Fukuhara et al. have reported two patients with "myoclonus epilepsy associated with ragged-red fibers" (MERRF), which is at present accepted as a distinctive clinical entity among the mitochondrial encephalomyopathies. We describe here postmortem findings of the case whose clinical findings were reported in detail by Fukuhara et al. (1980) as Case 1. The neuropathological findings were summarized as follows: 1) degeneration of dentate nucleus, red nucleus, globus pallidus, subthalamic nucleus and pontine tegmentum, 2) degeneration of the Clarke's column, spinocerebellar tract, posterior column and corticospinal tract, as well as of the posterior spinal nerve root and sural nerve, and 3) degeneration of substantia nigra, locus ceruleus, cerebellar cortex and inferior olivary nucleus. The lesions were degenerative in nature, and their distribution was different from those of dentato-rubropallidoluysian atrophy, Joseph's disease or Friedreich's ataxia. It was concluded that MERRF is a single disease entity also from pathological point of view.

Adult↗
PubMed1987

[Selectivity of cell degeneration and histological peculiarities of the repair process in the developing rat spinal cord after ethylnitrosourea administration].

We observed the selectivity of cell degeneration and histological peculiarities of the repair process in the lesion of developing rat spinal cord. Each of the 21 pregnant rats was given a single injection of ethylnitrosourea (ENU), 60 mg/kg body weight, in the tail vein on embryonic day 16. Each fetus was removed surgically from the dam every 2 hours for 24 hours and every 24 hours for 5 days. These fetuses were fixed by the transcardial perfusion to observe them with light and electron microscope. Degeneration was induced selectively in certain cells of the proliferating phase of the matrix cell layer and in the migrating neuroblasts in the alar plate. Individually affected cells were eliminated by phagocytes in the pre-existing extracellular space. No reactive gliosis, fibrosis, abnormal vascularization or infiltration of granulocytes and lymphocytes was observed at any time.

Animals↗