PubMed Health⌕ Search

Biomedical subjects

M Taniike

Publications and source records attributed to M Taniike.

At least 37 records · Page 2Linked to original sources
PubMed1994

Targeted disruption of the Hexa gene results in mice with biochemical and pathologic features of Tay-Sachs disease.

Tay-Sachs disease, the prototype of the GM2 gangliosidoses, is a catastrophic neurodegenerative disorder of infancy. The disease is caused by mutations in the HEXA gene resulting in an absence of the lysosomal enzyme, beta-hexosaminidase A. As a consequence of the enzyme deficiency, GM2 ganglioside accumulates progressively, beginning early in fetal life, to excessive amounts in the central nervous system. Rapid mental and motor deterioration starting in the first year of life leads to death by 2-4 years of age. Through the targeted disruption of the mouse Hexa gene in embryonic stem cells, we have produced mice with biochemical and neuropathologic features of Tay-Sachs disease. The mutant mice displayed < 1% of normal beta-hexosaminidase A activity and accumulated GM2 ganglioside in their central nervous system in an age-dependent manner. The accumulated ganglioside was stored in neurons as membranous cytoplasmic bodies characteristically found in the neurons of Tay-Sachs disease patients. At 3-5 months of age, the mutant mice showed no apparent defects in motor or memory function. These beta-hexosaminidase A-deficient mice should be useful for devising strategies to introduce functional enzyme and genes into the central nervous system. This model may also be valuable for studying the biochemical and pathologic changes occurring during the course of the disease.

Animals↗
PubMed1994

Absence of MHC class II molecules reduces CNS demyelination, microglial/macrophage infiltration, and twitching in murine globoid cell leukodystrophy.

Globoid cell leukodystrophy (GLD) is a severe genetic demyelinating disorder with an increased number of Ia (immune response antigen) positive brain microglia/macrophages. To assess the role of aberrant Ia expression in the central nervous system (CNS), twitcher mice, which represent the murine model for GLD, were mated with Ia- transgenic mice. Compared with the Ia+ controls, Ia- twitcher mice showed a profound reduction in the severity of demyelinating lesions correlated with significantly fewer microglia/macrophages. Most importantly, Ia- twitcher mice showed significantly reduced twitching compared with ia+ twitcher mice. In contrast with experimental allergic encephalomyelitis (EAE), there was no significant amount of inflammatory T cell infiltrates, implying that T cells may not play a predominant role in this disease. These findings may have broad therapeutic implications for Alzheimer's disease, Parkinson's disease, and Huntington's disease, which display enhanced Ia expression in the CNS without obvious T cell infiltrates.

Animals↗
PubMed1994

Spacio-temporal progression of demyelination in twitcher mouse: with clinico-pathological correlation.

The twitcher (twi/twi) is an authentic murine model of human globoid cell leukodystrophy (GLD), caused by a deficiency of galactosylceramidase. Similar to human GLD, the twitcher shows progressive deterioration of neurological function and its neuropathology is characterized by a collection of periodic acid-Schift stain (PAS)-positive macrophages in the areas of demyelination. However, there are some differences in the clinico-pathological aspects between human and murine GLD. We investigated the spacio-temporal progression of neuropathology in the twitcher from postnatal day (PND) 10 to 45. No clinical symptoms or neuropathological changes were apparent in twi/twi until PND 15. Generally, infiltration of macrophages, concomitant with myelin degeneration, was recognized in the cerebellar white matter and the brain stem after PND 20, then in cerebral white matter after PND 25, and in cerebral and cerebellar gray matter after PND 30. The demyelination was very severe in the radix of the 8th and the 5th cranial nerves. The neurological symptoms such as tremor, spasticity and cranial nerve dysfunction were well correlated with the progression of pathological changes. Demyelination progressed in an orderly fashion such that myelin degeneration began 10 to 20 days after the commencement of myelination in any of the given nerve fiber tracts. This suggests that there are no significant differences in the metabolism of galactocerebroside in the myelin and myelin-forming cells in individual nerve fiber tracts throughout the murine brain. Over-expression of glial fibrillary acidic protein was already present before the initiation of obvious demyelination.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1993

Case of ring chromosome 7: the first report of neuropathological findings.

We report on a boy with ring chromosome 7 who had severe mental retardation, growth failure, microcephaly, cleft lip and palate, café-au-lait spots, nevus flammeus, and genital abnormalities, and died of pneumonia at age 20 months. On autopsy he had fusion of the anterior cerebral hemispheres, accompanied by agenesis of olfactory bulbs and tracts, closely resembling those found in semilobar holoprosencephaly. In addition, heterotopic Purkinje cell clusters in the cerebellar white matter, absence of pigmentation within the brainstem pigmented neurons, and severe hypomyelination in the whole brain were noted. The patient may represent the most severe manifestation of ring chromosome 7, and this is the first detailed neuropathological report on this subject.

Abnormalities, Multiple↗
PubMed1993

Nephrosialidosis: ultrastructural and lectin histochemical study.

The neuropathological findings in a Japanese male with nephrosialidosis are reported. Clinically, coarse face, psychomotor retardation, macular cherry-red spot and proteinuria were noted at 1 year and 7 months. He was diagnosed to have nephrosialidosis on the basis of a deficiency of alpha-neuraminidase activity in both lymphocytes and cultured skin fibroblasts, and of severe glomerular and tubular involvement on renal biopsy. He died of multiple organ failure at 8 years and 6 months. There were numerous vacuoles and storage materials in visceral organs, particularly in the glomerular and tubular epithelial cells of the kidney and Kupffer cells as well as hepatocytes in the liver. Neuropathological examination revealed severe neuronal storage in the selected part of the central nervous system: lower motor neurons of the brain stem and spinal anterior horn cells, as well as neurons in the basal nucleus of Meynert. In the peripheral nervous system, sympathetic ganglia were severely affected. There was little or no neuronal storage in the basal ganglia, cerebral cortex or cerebellum, and demyelination was not found. Electron microscopic examination showed fine wavy multilamellar structures in the spinal anterior horn cells or Zebra body-like structures in the neurons of the Meynert's basal nucleus. Lectin histochemistry was positive for wheat germ agglutinin, Ricinus communis agglutinin-1 and peanut agglutinin within distended neurons. We conclude that the neuropathological feature in nephrosialidosis is not specific except for the selectiveness of the anatomical sites of involvement. It shares some aspects found in other types of sialidosis or galactosialidosis.

Brain↗
PubMed1993

Different clinical features in monozygotic twins: a case of 7q--syndrome.

We present male monozygotic twins who showed quite different clinical features. Blood chromosome analysis revealed 46,XY/46,XY,del(7) (q32-->qter) mosaicism in both twins. However, cultured skin fibroblasts from the twins showed different karyotypes. Twin 1, with a normal phenotype, had normal chromosomes and was 46,XY. Twin 2, on the other hand, had the characteristic manifestations of 7q- syndrome and chromosomes of 46,XY,del(7) (q32-->qter). DNA fingerprint analysis of their peripheral blood samples revealed the same pattern. However, DNA fingerprint patterns of cultured skin fibroblasts and buccal mucosal cells were different when a 7q terminal marker, probe g3, was used. These identical twins with discordant phenotypes can be explained by the occurrence of twinning and simultaneous erroneous mitosis. In addition, there might be a vascular communication which probably resulted in blood exchange and chromosomal mosaicism of the lymphocytes of the monozygotic twins.

Abnormalities, Multiple↗
PubMed1992

Mitochondrial tRNA(Ile) mutation in fatal cardiomyopathy.

A patient with mitochondrial encephalomyopathy who died from progressive intractable cardiac failure at the age of 18 is reported. At the age of 4, he presented with short stature, but multiorgan disorders including deafness, focal glomerulosclerosis, epilepsy and dilated cardiomyopathy appeared later in his clinical course. Laboratory tests showed hyperlactatemia and hyperpyruvatemia. Histopathological findings demonstrated mitochondrial myopathy with ragged red fibers and focal cytochrome C oxidase-deficient fibers in skeletal and cardiac muscles. The activity of cytochrome C oxidase was 30% less than the control level in skeletal muscle. Sequencing of the entire mitochondrial tRNA genome revealed a novel point mutation in the tRNA(Ile) region (nt 4269). This A-to-G substitution was found in none of the 30 controls by screening using mispairing PCR and Ssp I digestion methods, suggesting that this new mutation was pathogenic in our case.

Adolescent↗
PubMed1992

A case of pigmentary type of orthochromatic leukodystrophy with early onset and globoid cells.

We report herein a sporadic case of the pigmentary type of orthochromatic leukodystrophy with early onset and very rapid clinical course. The patient's development was normal until 2 years old, when he experienced visual disturbance. Rapid deterioration resulted in death 1.5 years after the onset. Metachromatic leukodystrophy, globoid cell leukodystrophy and adrenoleukodystrophy were excluded by biochemical assays. Autopsy findings were compatible with the diagnosis of the pigmentary type of orthochromatic leukodystrophy. However, there were unique findings of severe neuronal loss and the collection of globoid-like cells in the interface of the gray matter and the white matter. Immunohistochemical staining of myelin basic protein, proteolipid protein and galactocerebroside demonstrated that these myelin constituents were equally preserved in the posterior column, while absent in the lateral and anterior columns of the spinal cord.

Autopsy↗
PubMed1992

Mitochondrial encephalomyopathies with the mutation of the mitochondrial tRNA(Leu(UUR)) gene.

Four families with mitochondrial encephalomyopathy are described. Probands of three families had typical clinical presentations of mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS), but the proband of family 4 lacked strokelike episodes. The mitochondrial DNA mutation of tRNA(Leu(UUR)) (transfer ribonucleic acid specific to leucine (UUR codon)) found in MELAS was examined in muscle DNA obtained from biopsy samples of the probands of four families and the maternal relatives of family 2. The mutation was detected in all muscle samples, and the degree of the mutated DNA was 68% to 84% by Southern blot analysis. However, the clinical patterns of the maternal relatives of family 2 were mild and distinctly different from MELAS. The same mutation was also detected in blood-derived DNA samples of all family members examined, including healthy mothers but not fathers, although the degree of mutation did not correlate with the clinical severity. These results confirmed the maternal inheritance of this disease and suggested that the mitochondrial DNA mutation (tRNA(Leu(UUR))) may cause clinical symptoms other than MELAS. The clinical findings of mitochondrial encephalomyopathy should be reinvestigated in terms of the mitochondrial gene mutation; the polymerase chain reaction method will be useful for screening for this mutation of mitochondrial DNA in blood samples.

Acidosis, Lactic↗
PubMed1992

A case of Hallervorden-Spatz disease: progressive and intractable dystonia controlled by bilateral thalamotomy.

We present a 10-year-old girl with Hallervorden-Spatz disease diagnosed clinically from the neurological manifestations and the characteristic MRI findings. Her main symptom, dystonia, was progressive and resistant to medication, but this dystonia was controlled by bilateral thalamotomy. No clinical progression of the symptoms was recognized at 21 months from the last operation.

Child↗
PubMed1992

Serial magnetic resonance imaging studies in a case of late onset globoid cell leukodystrophy.

The late onset type of globoid cell leukodystrophy (GLD) is a rare disorder and only three magnetic resonance imaging (MR) studies have been reported for this disease. We report a sporadic case of late onset GLD. The illness started at the age of 3 years and 8 months with spastic gait. He became bedridden at the age of 4 years and 7 months. The diagnosis was made by deficient activity of galactosylceramidase in lymphocytes, and the biochemical and morphological examinations of the biopsied sural nerve were also conducted. Computed tomography (CT) and MR study revealed that the degenerative change of the white matter was initially recognized in the occipital and parietal lobes and then extended forward. Literature of the CT or MR findings of GLD is also reviewed.

Biopsy↗
PubMed1991

[Peripheral neuropathy in two children with mitochondrial encephalomyopathy].

Peripheral neuropathy (PN) associated with mitochondrial encephalomyopathy (MEM) has been reported in adult patients, while children with both conditions are rare. Electrophysiological and pathological studies disclosed evidence of PN in a 3-year-old girl and an 8-year-old boy with MEM. In both patients, peripheral nerve conduction velocities were reduced, while amplitudes of evoked potentials were normal. No ragged red fibers were found in the biopsy muscle, while most of the muscle fibers showed poor activity with histochemical staining for cytochrome c oxidase (CCO). Biochemical studies revealed deficiency of CCO in both cases. In the latter patient, CCO activity was also absent in the intramuscular peripheral nerve using CCO staining, and histopathological studies of the sural nerve revealed a marked decrease in the number of large myelinated fibers and an unusual accumulation of the mitochondria in the Schwann cell cytoplasm. These results may support the hypothesis that a common pathogenesis exists in both peripheral nerve and muscle due to mitochondrial dysfunction.

Age Factors↗
PubMed1990

A case of chronic GM1 gangliosidosis presenting as dystonia: clinical and biochemical studies.

Clinical and biochemical studies are reported on a 32-year-old man with GM1 gangliosidosis who presented with a slowly progressive dystonia that began when he was aged 7 years and eventually became almost totally incapacitating at the age of 35. There was only mild intellectual deterioration, but myoclonus, seizures and macular cherry-red spots were never observed. Proton-density and T2-weighted MRI scans showed symmetrical hyperintense lesions of both putamina. No increase of GM1 ganglioside was found in plasma or cerebrospinal fluid, and the metabolism of GM1 ganglioside in cultured skin fibroblasts from the patient was also almost normal, although the residual activity of GM1 ganglioside beta-galactosidase activity was only 10% of normal. These findings suggest that impaired GM1 ganglioside metabolism is not present systemically as it is in the infantile and juvenile types of the disorder, but is mainly confined to the central nervous system in chronic GM1 gangliosidosis.

Adult↗
PubMed1990

Study of pathogenesis in twitcher mouse, an enzymatically authentic model of Krabbe's disease.

The twitcher mouse was investigated by examining in vivo synthesis of galactosylceramide (Galcer) and galactosylsphingosine (Galsph) in a sciatic nerve culture, and in vitro enzymic activities for synthesis of Galcer and Galsph in the spinal cord from normal and affected mice. For the in vivo study, the sciatic nerve was incubated for 24 h in medium containing [3H]galactose, or [3H]-sphingosine-labeled Galcer or Galsph. With [3H]galactose, reduced synthesis of Galcer was found as early as 1 week of age and synthesis decreased to about 15% of normal value at 4 weeks. Increased Galsph was detected after 7 days of feeding with galactose. In a study of [3H]sphingosine-labeled Galcer and Galsph feeding, Galcer did not induce Galsph synthesis in either normal or affected mice, and synthesis of Galcer from Galsph was found only in normal mice, suggesting that Galcer was synthesized from sphingosine after hydrolysis of Galsph. In vitro, the activities of UDP-galactose: ceramide galactosyltransferase and UDP-galactose: sphingosine galactosyltransferase were reduced to less than 50% of control after 2 weeks of age in affected mice. We conclude that (1) decreased Galcer was due to impaired synthesis of Galcer, (2) Galsph was synthesized from galactose and not from deacylation of Galcer, and (3) Galsph accumulation was due not to increased synthesis but to decreased hydrolysis.

Age Factors↗
PubMed1990

Juvenile Sandhoff disease: a Japanese patient carrying a mutation identical to that found earlier in a Canadian patient.

A 35-year-old Japanese man with juvenile Sandhoff disease is described. He showed progressive neurogenic muscular atrophy, cerebellar ataxia and mental deterioration, beginning at age 10 years. The accumulation of GM2 ganglioside in the submucosal nerve cell was confirmed by positive immunostaining using anti-GM2 ganglioside antibody. Biochemical evaluation revealed nearly absent beta-hexosaminidase A and B activities in leukocytes and cultured fibroblasts. Hydrolysis of [3H]globoside I in the intact fibroblasts was apparently disturbed but the rate of hydrolysis was higher than those seen in cells from patients with infantile Sandhoff disease. Analysis of the beta-hexosaminidase beta-subunit gene of the patient disclosed a point mutation (a G-to-A transition) within intron 12. The mutation generates a new splice junction resulting in a 24-base insertion between exons 12 and 13 in the processed mRNA and consequently an 8-amino acid insertion in the translation product. This mutation is identical to that originally found in a Canadian patient with juvenile Sandhoff disease. A possible relationship with the clinical phenotype and the gene abnormality is discussed.

Adult↗