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M Taniike

Publications and source records attributed to M Taniike.

At least 19 recordsLinked to original sources
PubMed2006

Lipocalin-type prostaglandin D synthase (beta-trace) is upregulated in the alphaB-crystallin-positive oligodendrocytes and astrocytes in the chronic multiple sclerosis.

Lipocalin-type prostaglandin D synthase (L-PGDS), which is mainly synthesized in leptomeningeal cells and oligodendrocytes (OLs) in rodents and humans, is secreted into the human cerebrospinal fluid (CSF) as beta-trace. L-PGDS protects OLs and neurones against apoptosis in twitcher mice, a murine model of Krabbe's disease, and is the second only to a stress protein, alphaB-crystallin, as the most abundant gene product upregulated in the demyelinating focus of multiple sclerosis (MS). Here we report that although the CSF level of L-PGDS is not increased in MS patients, L-PGDS is increased in the white matter of MS patients, especially in the shadow plaque as compared with the normal white matter. L-PGDS immunoreactivity was intensely expressed in OLs within the shadow plaques and in hypertrophied astrocytes within the chronic plaques of MS patients. Both L-PGDS-positive OLs and astrocytes expressed a stress protein, alphaB-crystallin. These results suggest that the upregulation of L-PGDS occurs in OLs and astrocytes as a stress reaction.

Adult↗
PubMed2005

Acute myocardial infarction caused by a septic coronary embolism diagnosed and treated with a thrombectomy catheter.

Acute myocardial infarctions are common in bacteraemia but are seldom diagnosed during life. A 64 year old man with severe chest pain who had fever for several days due to possible bacteraemia was shown by ECG and echocardiography to have possible lateral infarction. Immediate coronary angiography showed possible thrombus in the left circumflex artery, which was treated by thrombectomy catheter. Bacterial thrombus was removed and was verified by histological examination. A stent was implanted without complications. Acute myocardial infarction caused by septic embolism is usually fatal; however, thrombectomy may be useful in these cases.

Cardiac Catheterization↗
PubMed2000

Mature oligodendrocyte apoptosis precedes IGF-1 production and oligodendrocyte progenitor accumulation and differentiation during demyelination/remyelination.

We have documented changes in the oligodendrocyte population during demyelinating insult to the adult CNS. Feeding of cuprizone to adult mice led to apoptotic death of mature oligodendrocytes followed by profound demyelination of the corpus callosum. A regenerative response was initiated even during active demyelination. Oligodendrocyte progenitors have begun to proliferate and then accumulate within the lesion. Many of these cells may have migrated from the sub-ventricular zone and fornix before their accumulation in the demyelinating corpus callosum. The accumulation of differentiating oligodendrocyte progenitors was followed closely by the reappearance of mature oligodendrocytes and remyelination. Interestingly, an increase in IGF-1 mRNA was detected at Week 3 through Week 7, suggesting potential involvement in remyelination. Other factors, however, such as PDGF, NT3, FGF, jagged, and notch remained unchanged. These results suggest that the mature oligodendroglial population depleted by apoptosis is replaced by a newly formed oligodendroglial population derived from progenitors; these accumulate and seem to differentiate during remyelination.

Animals↗
PubMed1999

Lineage switch in childhood leukemia with monosomy 7 and reverse of lineage switch in severe combined immunodeficient mice.

Morphophenotypic lineage switches occur in a small percentage of those with acute leukemia, and the underlying mechanisms are not clear. In this study, we attempted to induce a lineage switch in acute myelocytic leukemia (AML) with monosomy 7, whose lineage had switched from acute T-lymphocytic leukemia (T-ALL) during chemotherapy, in severe combined immunodeficient (SCID) mice. Although the transplanted myeloid cells were engrafted in SCID mice without cytokine administration, T-ALL developed in SCID mice treated with recombinant human granulocyte-macrophage colony-stimulating factor or recombinant human interleukin 3. Analysis of the nucleotide sequences of the rearranged T-cell receptor gamma-chain (TCR-gamma) gene revealed that this lineage switch resulted from the selection of the T-lineage subclone in SCID mice, which had expanded at onset. In addition, we found that the T-lineage and myeloid cells belonged to the distinct subclones, which were different in TCR-gamma gene rearrangements, but were derived from a common clone with an identical N-ras gene mutation for both subclones. In in vitro cultures, only the myeloid subclone grew; the T-lineage subclone failed to grow even in the presence of recombinant human granulocyte-macrophage colony-stimulating factor or recombinant human interleukin 3. These results suggested that the initial diagnostic T-lymphoid subclone, whose growth was dependent on these cytokines and the hematopoietic microenvironment, emerged from a bipotential T-lymphoid/myeloid leukemic stem cell, and further genetic event(s) induced the myeloid subclone, which grew independently of these cytokines and the microenvironment.

Acute Disease↗
PubMed1999

An apoptotic depletion of oligodendrocytes in the twitcher, a murine model of globoid cell leukodystrophy.

Morphological alterations of oligodendrocytes (OLs) leading to their depletion were studied in the genetic demyelinating mutant, twitcher, a murine model of globoid cell leukodystrophy (GLD). With pi-glutathione-S-transferase immunostaining, OLs with multiple varicose processes were recognized in the early stages and adjacent areas of demyelination and then the OLs cytoplasm as well as the processes became shrunken with progression of the disease. These shrunken OLs were labeled by the TUNEL method, indicative of apoptotic cell death. The ultrastructural features of apoptotic cells were noted in these OLs and DNA laddering was noted in the twitcher brain in advanced stages. This is the first report describing the gradual depletion of OLs by apoptosis in genetic demyelination.

Animals↗
PubMed1998

A case of Kearns-Sayre syndrome showing a constant proportion of deleted mitochondrial DNA in blood cells during 6 years of follow-up.

Kearns-Sayre syndrome (KSS) and Pearson syndrome (PS) show quite different phenotypes despite the same underlying genetic defect, i.e. a large deletion of one population of mitochondrial (mt) DNA. The main feature of KSS is progressive encephalomyopathy; on the other hand, PS shows fatal hematological problems in early infancy. Through Southern blot analysis of mtDNA of blood cells, deletion has been consistently found in patients with PS but usually undetectable in KSS patients. Therefore, their different clinical phenotypes have been explained by the different tissue distribution of mutant mtDNA. Recently, a few cases were reported which had features of PS in infancy and later developed KSS. These observations suggest that phenotypes may also be modified by the selection process involving mtDNA within different tissues. We found a case of KSS, who initially presented endocrinological dysfunction such as insulin-dependent diabetes mellitus (IDDM) and growth hormone (GH) deficiency, and had not developed external ophthalmoplegia until the age of 17. Although he did not show any symptoms of PS, a marked proportion of mtDNA was deleted not only in muscle but also in blood cells. Analysis of his blood cells showed an unchanged proportion of deleted mtDNA at three estimations within 6 years of the follow-up period. This case provides evidence that deleted mtDNA in blood cells also has a stable replicative capacity and that a large proportion of deleted mtDNA in blood cells may not accompany hematological problems.

Anemia, Sideroblastic↗
PubMed1998

Suppressed UDP-galactose: ceramide galactosyltransferase and myelin protein mRNA in twitcher mouse brain.

The developmental changes in expression of steady-state mRNA that encode proteins that are important for myelination (myelin basic protein, myelin-associated glycoprotein, proteolipid protein, UDP-galactose: ceramide galactosyltransferase) and glial fibrillary acidic protein were investigated in the brain of the twitcher mouse, a model of human globoid cell leukodystrophy. This disease is caused by a mutation in the gene encoding the lysosomal enzyme, galactosylceramidase, which catalyzes the degradation of the myelin lipid galactosylceramide. Before postnatal day (PND) 20, the levels of myelin protein mRNA were similar in twitcher and normal mice. With progression of demyelination after PND 25-30, myelin protein mRNA levels gradually decreased. The period of maximum expression of the myelin protein genes in twitcher mice was, however, similar to that of normal control mice. mRNA levels for the gene that encodes the enzyme UDP-galactose:ceramide galactosyltransferase which is responsible for catalyzing the final step in galactosylceramide synthesis, was exceptionally down-regulated from the early stages of the disease. The increase of glial fibrillary acidic protein (GFAP) mRNA levels preceded morphological evidence of demyelination.

Animals↗
PubMed1998

A case of giant axonal neuropathy showing focal aggregation and hypophosphorylation of intermediate filaments.

We report here the clinicopathological features of a typical case of giant axonal neuropathy (GAN). Scanning electron microscopy of the hair of this case revealed an extraordinarily irregular cuticle. Focal accumulation of intermediate filaments in axons, Schwann cells, muscle fibers and skin fibroblasts were also found under an electron microscopy. When examined immunocytochemically, muscle fibers exhibited local disruption of the filamentous network in the subsarcolemmal space and in the central cytoplasm accompanied by focal accumulation of desmin. The intracellular network of vimentin was also disrupted, exhibiting global accumulation in some of the cultured skin fibroblasts. Decreased interneurofilament spacing was found in enlarged axons, suggesting the presence of hypophosphorylation of neurofilaments in this patient. These findings suggest general disorganization, abnormal distribution and possible defective phosphorylation of intermediate filaments in GAN.

Axons↗
PubMed1998

[A case of juvenile type dentatorubral-pallidoluysian atrophy (DRPLA) with psychomotor retardation since infancy].

We report here a case of an 11-year-old boy with juvenile type of dentatorubral-pallidoluysian atrophy (DRPLA). His psychomotor development has been delayed since infancy and cerebellar ataxia was noted at the age of 2 years, indicating an early onset. At the age of 6 years, he had progressive myoclonus epilepsy (PME) and underwent a series of neuroradiological, electrophysiological and pathological examinations, which failed to reveal the etiology. Gene analysis performed at the age of 11 years revealed an expanded CAG repeat at the DRPLA locus in both the patient and his asymptomatic father. In the absence of a positive family history, a diagnosis of DRPLA may be difficult due to its clinical variability. We conclude that DRPLA should be taken into account in the differential diagnosis of childhood PME and that gene analysis should be performed to confirm a diagnosis of DRPLA.

Anticipation, Genetic↗
PubMed1997

Expression of major histocompatibility complex class I antigens in the demyelinating twitcher CNS and PNS.

The expression of the major histocompatibility complex Class I antigens (Class I) was investigated in the nervous system of twitcher (C57BL/6J-twi), a murine model of Krabbe disease in humans. Class I mRNA expression was low in wild type and in twitcher mice prior to the onset of demyelination. However, immunoreactivity for Class I antigens was demonstrated in the spindle-shaped cells in the sciatic nerve and in ramified microglia, endothelial cells and Bergmann glia. In twitcher, transcription of Class I mRNA increased significantly with the progression of demyelination and Mac-1+ macrophages/microglia express Class I immunoreactivity. Class I immunoreactivity was also found in CD3+ T-cells that were scattered in demyelinating lesions. CD8+ or CD4+ cells were also found in the demyelinating area. The results of this study indicate that immunoreactivity to Class I antigens is detected in certain cells even in the wild-type mice and that Class I expression is enhanced in the twitcher nervous system paralleling the progression of demyelination. Expression of MHC molecules in non-immunological demyelinating disease such as twitcher may suggest a role of Class I molecules in the progression of demyelination. Alternatively, the expression may be a non-specific cellular response to the breakdown of myelin.

Animals↗
PubMed1996

Molecular cloning and expression of cDNA for murine galactocerebrosidase and mutation analysis of the twitcher mouse, a model of Krabbe's disease.

The cDNA for a murine galactocerebrosidase was isolated from a murine testis cDNA library on the basis of its homology with the cDNA for human galactocerebrosidase and a PCR method was used to clone the 5' end. It has a 2,278-nucleotide sequence including a 2,004-nucleotide open reading frame, which encodes 668 amino acid residues. The identity between the human and murine amino acid sequences was very high, being calculated to be 84%. Sequencing of cDNA from liver of the twitcher mouse revealed a nonsense mutation at codon 339 (TGG-->TGA). The most abundant mRNA of the murine galactocerebrosidase gave a 3.6-kb band, which was not detected in twitcher mice. This suggests that the cDNA (2,278 bp) we characterized represents a minor species generated by an alternate poly(A) signal and that most of the mRNA has a much longer 3'-untranslated region. Genome analysis revealed that this mutation was homozygous in the twitcher and heterozygous in the carrier but was not present in normal mice. The normal mouse cDNA but not the mutant cDNA of the galactocerebrosidase transfected into COS1 cells gave rise to an increase in enzymatic activity. We concluded that this mutation results in the deficiency of galactocerebrosidase in the twitcher mouse.

Amino Acid Sequence↗
PubMed1995

Murine model of genetic demyelinating disease: the twitcher mouse.

Twitcher mouse is an authentic murine model of human genetic demyelinating disease, globoid cell leukodystrophy (GLD), or Krabbe disease. Since its discovery at the Jackson Laboratory (Bar Harbor, ME) this model has been used extensively for the morphological, biochemical-enzymatic studies to clarify pathogenesis and also for therapeutic manipulation of genetic demyelinating disease in humans. As a result of these studies, now we know that (1) GLD is caused by a deficiency of lysosomal enzyme galactosylceramidase, and a toxic metabolite, psychosine, accumulates in the tissue, including the nervous system, damaging myelin forming cells and resulting in secondary demyelination; (2) morphological features of demyelination and associated cellular reactions in demyelination in this mutant are similar to those seen in autoimmune or toxic demyelination; and (3) with enzyme supplementation provided by bone marrow transplantation, remyelination occurs to some extent in demyelinated fibers in both central and peripheral nervous systems of twitcher mouse.

Animals↗
PubMed1995

Proliferative capacity of oligodendrocytes in the demyelinating twitcher spinal cord.

The proliferative capacity of oligodendrocytes was investigated in the spinal white matter of the twitcher mouse, a murine model of a genetic demyelinating disease globoid cell leukodystrophy (GLD), in which degeneration of oligodendrocytes due to metabolic perturbation has been well documented. In normal mice at 30 and 45 days of age, proliferating cells labeled with 5-bromo-2'-deoxyuridine (BrdU) were scarce, and the majority of BrdU-labeled cells did not immunostain with antibodies for oligodendrocytes, astrocytes, or microglia/macrophages. Only a few cells with markers for oligodendrocytes, carbonic anhydrase (CA), or the Pi form of glutathione-S-transferase (Pi), were labeled with BrdU. In the twitcher spinal cord, total numbers of BrdU-labeled cells were almost 6 times that of the normal littermate mice at 30 days of age, and 28 times at 45 days of age. However, this increase was largely due to an increase of cells labeled with F4/80, a marker for the microglia/macrophages. CA or Pi positive cells only constituted less than 10% of all labeled cells. With progression of demyelination from 30-45 days, total numbers of CA positive or Pi positive oligodendrocytes decreased, but percentages of cells double-labeled with BrdU and CA or Pi remained fairly constant. The results indicated that oligodendrocytes proliferated, to some extent, in the twitcher despite the genetic metabolic defect, and their decrease in number with progression of disease was not due to declined proliferation but rather cellular degeneration as the result of an intrinsic metabolic perturbation.

Animals↗
PubMed1995

Neuropathology of mice with targeted disruption of Hexa gene, a model of Tay-Sachs disease.

A murine model of Tay-Sachs disease, the prototype of the GM2 gangliosidoses, was produced through the targeted disruption of the Hexa gene encoding the subunit of alpha-hexosaminidase A. The mice were completely devoid of beta-hexosaminidase A activity and accumulated GM2 ganglioside in the CNS in an age-dependent manner. Neurons with membranous cytoplasmic bodies (MCBs), identical to those described in Tay-Sachs disease, were identified in the brain of these mice. The neurons with MCBs were periodic acid-Schiff-positive on frozen sections and immunostained with anti-GM2 ganglioside antibody. However, unlike Tay-Sachs disease in which neurons throughout the brain are affected, the localization of storage neurons in these mice appeared to be limited to certain regions, i.e., cerebral cortex, the hippocampus, amygdala, hypothalamus, mammillary nucleus, etc. Storage neurons were absent in the olfactory bulb, cerebellar cortex and spinal anterior horns. The difference in the distribution of storage neurons suggests a difference of ganglioside metabolism between humans and mice. This model is useful for the study of the pathogenic mechanisms of neuronal storage in Tay-Sachs disease and for the evaluation of therapeutic strategies.

Animals↗
PubMed1995

Focal cytochrome c oxidase deficiency in the brain and dorsal root ganglia in a case with mitochondrial encephalomyopathy (tRNA(Ile) 4269 mutation): histochemical, immunohistochemical, and ultrastructural study.

This is the first report with histochemical and immunohistochemical techniques of an autopsy case with mitochondrial encephalomyopathy caused by the mitochondrial tRNA(Ile) (nt4269) A to G mutation showing focal cytochrome c oxidase (COX) deficiency of neuronal cells. The 18-year-old male patient had cardiomyopathy, hearing disability, mental retardation, and seizures. Muscle biopsy exhibited many ragged-red fibers and focal COX deficiency. A postmortem histochemical study on frozen sections of the cerebral cortex, cerebellum, brain stem, and dorsal root ganglia revealed a loss of COX activity in some neuronal cells. On immunohistochemical staining, COX was also defective in a mosaic pattern. Focal COX deficiency may cause variable neurological manifestations in mitochondrial encephalomyopathies.

Adolescent↗
PubMed1995

Molecular defects in Krabbe disease.

Krabbe disease (globoid cell leukodystrophy) is an autosomal recessive neurodegenerative disorder that affects both the central and peripheral nervous systems due to an enzymatic defect of the galactocerebrosidase. In this study, molecular defects in Krabbe disease were investigated in 11 patients (seven Japanese and four non-Japanese) using cultured skin fibroblasts. A Japanese late infantile patient had a missense mutation of Pro at codon 302 to Ala and a non-Japanese patient had a missense mutation of Val at codon 550 to Gly. The reduced enzymatic activities expressed from the cDNAs with these missense mutations and from the previously reported nonsense mutation (E369X, Glu at codon 369 to stop codon) were confirmed. Genomic DNA analyses revealed that the P302A and E369X mutations were heterozygous and the V550G mutation was homozygous in these patients. A 12 base deletion with a 3 base insertion was found in three unrelated Japanese infantile patients, but not in 30 controls. The mutation was homozygous in two patients and heterozygous in one patient. We could not find any confirmed mutation in the coding region in the other six patients. These findings suggest that mutations in infantile and late infantile patients are relatively heterogeneous.

Amino Acid Sequence↗