Biomedical subjects

M Mizuguchi

Publications and source records attributed to M Mizuguchi.

At least 127 records · Page 7Linked to original sources

PubMed1994

Expression of Bcl-2 protein in murine neural cells in culture.

To explore the role of the protooncogene bcl-2 in the prevention of programmed cell death in the nervous system, we investigated its expression in mouse neural cells in primary culture. The 26 kDa protein product, Bcl-2, was detected by immunocytochemistry and immunoblotting in cultured neurons, astrocytes and oligodendrocytes, but the immunoreactivity of microglial cells was not detectable by immunoblotting. The subcellular distribution of Bcl-2 was similar between in vivo (brain) and in vitro (culture) and between cultured neurons and astrocytes, while the content was higher in astrocytes than in neurons. The substantial expression of bcl-2 in primary cultured brain cells suggests that it has some physiological control in the brain over programmed cell death, which may be exerted not only in neurons but also in some glial cells such as astrocytes.

Animals↗

PubMed1994

Distribution of leptomeningeal glioneuronal heterotopia in alobar holoprosencephaly.

OBJECTIVE: To clarify the pathogenetic significance of the topographic distribution of leptomeningeal glioneuronal heterotopia, a common finding in holoprosencephaly. DESIGN: Gross, histological, and immunohistochemical observations of alobar holoprosencephaly in brain specimens taken at autopsy. SETTING: Referral center. MATERIALS: Brains removed at autopsy from five consecutive patients with alobar holoprosencephaly. MAIN OUTCOME MEASURES: Immunoperoxidase staining for glial fibrillary acidic protein. RESULTS: In all brains, leptomeningeal glioneuronal heterotopia showed an identical distribution, ranging from the basal prosencephalon to the pons, with the thickest distribution occurring in the basal prosencephalon. CONCLUSION: The constant localization implicates leptomeningeal glioneuronal heterotopia in severe dysgenesis of midline prosencephalon, the basic pathogenesis of the anomaly.

Choristoma↗

PubMed1994

High expression on Kunitz-type protease inhibitor-containing substances in the cerebral vessels of patients with Down syndrome.

Down syndrome (DS) brains, from 19 gestational weeks to 50 years of age were studied by immunohistochemical methods with a polyclonal antibody against synthetic peptide comprising part of the Kunitz-type protease inhibitor (KPI) domain of Alzheimer disease amyloid precursor protein (APP), residues 301 to 323 of APP 770. In DS, positive KPI immunoreactivity was observed in early infancy and from child to adulthood on the tunica media of the arteries in the leptomeninges, cerebral cortex and white matter, but negative or little in controls. In DS with Alzheimer type dementia, KPI immunoreactivity in the arteries was reduced, but a gross granular reactivity was noted in neurons and glial cells. The high expression of KPI in DS vessels may be one of the predisposing factors to vascular diseases and amyloid deposition associated with DS.

Adolescent↗

PubMed1994

Hyperplastic polyps following treatment of acute gastric ulcers.

Although hyperplastic polyps are the most common polyps of the stomach, the etiology of these polyps is not completely understood. We report a 61-year-old woman who developed gastric hyperplastic polyps following acute gastric lesions. She was admitted for endoscopic injection sclerotherapy of esophageal varices. After the end of sclerotherapy, acute gastric lesions developed. For treatment of the lesions, omeprazole was used for 8 weeks followed by famotidine for 8 weeks. At the end of the treatment, she developed multiple gastric hyperplastic polyps, suggesting that acute gastric lesions and/or treatment of the gastric lesions are related to the development of hyperplastic polyps in the stomach.

Esophageal and Gastric Varices↗

PubMed1994

Myoclonic epilepsy and a maternally derived deletion of 15pter-->q13.

Deletion of a 15pter-->q13 segment of maternal origin was observed in a mentally retarded infant. In addition to the symptoms common to deletions of proximal 15q, the phenotype included myoclonic epilepsy of early infantile onset. The deletion was caused by a 3:1 disjunction in the mother, who was a carrier of t(15;22)(13q;p11) translocation.

Chromosome Deletion↗

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

Pulmonary carcinoma associated with hamartoma in an 11-year-old boy.

PURPOSE: We describe a poorly differentiated adenocarcinoma of the lung in an 11-year-old boy who had had a pulmonary hamartoma for at least 8 years. CONCLUSIONS: A hamartoma, even if clinically silent, may lead to the development of malignant tumors on rare occasions.

Adenocarcinoma↗

PubMed1993

[Movement disorders in miscellaneous disorders--inherited metabolic diseases].

A variety of inheritable metabolic disorders produce movement disorders. A lists of conditions associated with tremor, athetosis, chorea, dystonia and myoclonus are presented as a guide for the differential diagnosis of such abnormal involuntary movements. The list includes aminoacidopathies, lipidoses, mucopolysaccharidoses, mucolipidoses, organic acidemias, mitochondrial cytopathies and disorders of carbohydrate, purine, and metal metabolism. Clinical, pathological and biochemical features of movement disorders of three typical examples, Wilson's disease, Lesch-Nyhan syndrome and glutaric acidemia type 1, are described.

Diagnosis, Differential↗

PubMed1992

Differential distribution of cellular forms of beta-amyloid precursor protein in murine glial cell cultures.

The production and localization of cell-associated forms of beta-amyloid precursor protein (APP) of Alzheimer's disease was investigated in primary cultures of mouse glial cells. In both oligodendrocytes and astrocytes, immunofluorescence staining with an antibody against the carboxy terminus of APP revealed an intense cytoplasmic immunoreactivity. Immunoblotting of the cell extracts detected differences in the composition of APP between oligodendrocytes and astrocytes, notably the abundance of 107 kDa subtype in oligodendrocytes. Differences in immunoblot patterns were also noted between two buffer-insoluble, membrane-rich subcellular fractions of the glial cells, nuclear-mitochondrial and microsomal; the 119 kDa APP was enriched in the former, whereas the 73 and 115 kDa APPs in the latter. The results suggest that each APP subspecies may play a distinct functional role in different cell types and subcellular fractions.

Amyloid beta-Protein Precursor↗

PubMed1992

Ultrastructural localization of inositol 1,4,5-trisphosphate 3-kinase in rat cerebellar cortex.

Subcellular localization of inositol 1,4,5-trisphosphate 3-kinase in the rat cerebellar cortex was studied immunohistochemically using a monoclonal antibody. Electron microscopy revealed intense immunoreactivity in the dendritic spines of Purkinje cells forming synapses with the parallel fibers, climbing fibers and recurrent collaterals of Purkinje cell axons. The labelling was associated with the hypolemmal cisternae, surrounding matrix and plasmalemma including the postsynaptic densities. Weaker immunoreactivity was present in the dendritic spines of basket cells and in certain segments of Purkinje cell recurrent collaterals. The postsynaptic regions of the dendritic trunks of Purkinje and basket cells were negative. These results indicate that inositol 1,4,5-trisphosphate 3-kinase is distributed amongst the spines of various synaptic relations with different electrophysiological properties, and that axon terminals of certain cell types are another functional site for the enzyme.

Animals↗

PubMed1992

Development of inositol 1,4,5-trisphosphate 3-kinase immunoreactivity in cerebellar Purkinje cells in vivo and in vitro.

Development profiles in vivo and in vitro of inositol 1,4,5-trisphosphate 3-kinase (IP3K) were investigated immunohistochemically in the cerebellar Purkinje cells. In in vivo preparations of rat cerebellum, IP3K immunoreactivity appeared in Purkinje cell bodies and dendrites shortly after birth, increased rapidly by postnatal day 5, and was subsequently confined to their dendritic processes by day 20. The appearance and shift of IP3K immunoreactivity in Purkinje cells showed an identical time course even when Purkinje cells were placed under culture conditions commencing on day 0, suggesting that Purkinje cells have their own biological clock on the expression of IP3K in the absence of external influences.

Animals↗

PubMed1992

beta-Amyloid precursor protein of Alzheimer's disease in cultured bovine oligodendrocytes.

The production of beta-amyloid precursor protein (beta APP) in cultured oligodendrocytes isolated from adult bovine brains was examined by immunohistochemistry and immunoblotting. Immunostaining of oligodendrocytes with antibodies specific for the carboxy terminus of beta APP demonstrated positive immunoreactivity of oligodendroglial cytoplasm. Immunoblot analysis of cellular extracts detected two distinct bands with estimated molecular weight of 118 and 105 kDa. The amount of these beta APP subspecies increased considerably in response to their attachment to the poly-L-lysine substratum.

Alzheimer Disease↗

PubMed1992

Calbindin D-28k and parvalbumin immunohistochemistry in developing rat retina.

The developmental profiles of two calcium-binding proteins, calbindin-D28k (CaBP) and parvalbumin (PV), were investigated immunohistochemically in the developing rat retina. CaBP-immunoreactivity appeared first on embryonic day 17 in the horizontal, amacrine and ganglion cells; on embryonic day 21 in the inner plexiform layer; and on post-natal day 6 in the outer plexiform layer. The reaction intensity had increased to its maximum level by post-natal day 10. PV-immunoreactivity was first noted on embryonic day 19 in the amacrine and ganglion cells and reached its maximum on post-natal day 10. Two distinct subpopulations of amacrine cells were clearly recognized after post-natal day 6; one was positive for CaBP and the other for PV. Some morphological differences were noted between the two.

Animals↗

PubMed1992

Alzheimer's disease beta-amyloid precursor protein in rat neural cells in culture.

Immunochemical studies were performed on Alzheimer's beta-amyloid precursor protein (APP) in rat brain and cultured rat neural cells. Multiple APP subtypes were detected on immunoblots of brain homogenate with several antisera specific for subsequences of APP. In rat neural cell cultures, it was demonstrated that the composition of APP subtypes differed among cell types and subcellular fractions, and that APP subtypes in PC12h cells varied in their heparin binding affinity, suggesting distinct functional roles for different APP subtypes. Compatible with the possible role of APP in cell-matrix interaction, an increase in oligodendroglial APP was observed following their attachment onto poly-L-lysine substratum.

Alzheimer Disease↗

PubMed1991

Phospholipase C isozymes in neurons and glial cells in culture: an immunocytochemical and immunochemical study.

Expression of 3 brain isozymes of phospholipase (PLC-beta, PLC-gamma and PLC-delta) was investigated in relation to cell types found in rat CNS cultures. Immunoreactivity of cultured neurons, astrocytes and oligodendrocytes was demonstrated for all of the 3 isozymes by immunocytochemical staining and immunoblotting, with some differences in reaction intensity. Immunoblotting revealed that the level of expression was neurons greater than oligodendrocytes greater than astrocytes for PLC-beta and PLC-gamma, and astrocytes greater than oligodendrocytes greater than neurons for PLC-delta.

Animals↗

PubMed1991

Alpha 1-antichymotrypsin supports short-term survival of cerebral neurons in culture.

alpha 1-Antichymotrypsin (ACT) is a component of the amyloid deposits in Alzheimer's disease. To elucidate its biological activities in the central nervous system, dissociated cultures of rat cerebral neurons were grown in a serum-free medium containing ACT. The addition of ACT (0.1-1 microgram/ml) enhanced survival of microtubule-associated protein 2-immunoreactive neurons under the culture conditions examined.

Animals↗

PubMed1991

Developmental changes of three phosphoinositide-specific phospholipase C isozymes in the rat nervous system.

Developmental changes of 3 phosphoinositide-specific phospholipase C isozymes (PI-PLC-beta, PI-PLC-gamma and PI-PLC-delta) in the rat nervous system were studied by immunohistochemical and immunochemical methods. PI-PLC-gamma immunoreactivity was intensely expressed in the radial fibers from the late fetal to early newborn stages, while weaker PI-PLC-beta reaction was also demonstrated in these structures. PI-PLC-beta and PI-PLC-gamma immunoreactivity appeared in neurons of various regions after the first postnatal week and then increased to the adult stage. Bergmann glia and some astrocytes also showed weak immunoreactivity for both isozymes from the newborn stage, while such immunoreactive astrocytes were relatively restricted in distribution in the white matter and hippocampus at the adult stage. PI-PLC-delta immunoreactivity appeared in astrocytes of entire cerebral regions from the second postnatal week, although weak antigenicity was also present in some neurons. Immunoblot analysis revealed that the immunoreactivities of 3 PI-PLC isozymes were present in both fetal and adult brains, with strong reactions of PI-PLC-beta and PI-PLC-delta in adult brain and that of PI-PLC-gamma in fetal brain. These results suggest that each PI-PLC isozyme plays important roles in different cell types in the course of their differentiation, and that some PI-PLC isozymes, especially PI-PLC-gamma, may be involved in cellular division and growth during the histogenesis of the central nervous system.

Animals↗