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T Tomoda

Publications and source records attributed to T Tomoda.

At least 19 recordsLinked to original sources
PubMed2001

Activated Notch2 signaling inhibits differentiation of cerebellar granule neuron precursors by maintaining proliferation.

In the developing cerebellar cortex, granule neuron precursors (GNPs) proliferate and commence differentiation in a superficial zone, the external granule layer (EGL). The molecular basis of the transition from proliferating precursors to immature differentiating neurons remains unknown. Notch signaling is an evolutionarily conserved pathway regulating the differentiation of precursor cells of many lineages. Notch2 is specifically expressed in proliferating GNPs in the EGL. Treatment of GNPs with soluble Notch ligand Jagged1, or overexpression of activated Notch2 or its downstream target HES1, maintains precursor proliferation. The addition of GNP mitogens Jagged1 or Sonic Hedgehog (Shh) upregulates the expression of HES1, suggesting a role for HES1 in maintaining precursor proliferation.

Animals↗
PubMed2000

Discoidin domain receptor 1 functions in axon extension of cerebellar granule neurons.

In the developing cerebellum, granule neuron axon outgrowth is a key step toward establishing proper connections with Purkinje neurons, the principal output neuron of the cerebellum. During a search for genes that function in this process, we identified a receptor tyrosine kinase discoidin domain receptor 1 (DDR1) expressed in granule cells throughout their development. Overexpression of a dominant-negative form of DDR1 in immature granule cells results in severe reduction of neurite outgrowth in vitro, in dissociated primary culture, and in vivo, in organotypic slices of neonatal cerebellum. Granule cells that fail to extend axons are positive for differentiation markers such as TAG-1 and the neuron-specific class III beta-tubulin, suggesting that development is affected after granule cells commit to terminal differentiation. DDR1 activation appears to be mediated by its ligand, collagen, which is localized to the pial layer of the developing cerebellum, thereby leading to granule cell parallel fiber extension. Our results therefore indicate that collagen-DDR1 signaling is essential for granule neuron axon formation and further suggest a unique role of pia in cerebellar cortex histogenesis.

Animals↗
PubMed2000

Computerized tomographic ureteroscopy for diagnosing ureteral tumors.

PURPOSE: Helical computerized tomography (CT) image acquisition has led to the availability of improved data sets for CT endoscopic imaging that represent virtual endoscopy using CT. We assessed the usefulness of CT ureteroscopic imaging for diagnosing ureteral tumors. MATERIALS AND METHODS: A total of 16 patients with ureteral stenosis underwent surface rendering CT ureteroscopy after the intravenous administration of contrast material and furosemide. To distinguish ureteral tumors from ureteral strictures 2 observers blinded to other patient history and evaluation data independently and prospectively evaluated CT ureteroscopy with reformatted CT ureterograms in these 16 patients. CT ureteroscopic images were then correlated with surgical and pathological findings, which served as the gold standard. RESULTS: Surgical and pathological findings in the 16 patients revealed 16 ureteral tumors, including carcinoma in 10 (carcinoma in situ in 1, fibroepithelial polyps in 2 and hyperplastic polypoids in 4), inflammatory intrinsic stricture in 2 and extrinsic stricture in 4 caused by retroperitoneal fibrosis in 2 and lymph node metastasis in 2. CT ureteroscopy correctly detected all lesions except 1 carcinoma in situ, 1 polypoid carcinoma and 1 hyperplastic polypoid. The sensitivity and specificity of CT ureteroscopy for detecting ureteral tumors and carcinoma were 81% and 100%, and 80% and 75%, respectively, when tumors without stalks were considered carcinoma. CONCLUSIONS: CT ureteroscopy is useful for visualizing the complex morphology of ureteral tumors and distinguishing tumor from ureteral stricture.

Adult↗
PubMed2000

[Treatment of renal cell carcinoma extending into the right atrium with extra-corporeal circulation using high-grade hypothermia: a case report].

A 68-year-old woman underwent surgical treatment for renal cell carcinoma associated with tumor thrombus extending into the right atrium. Although the tumor thrombus reached the level of the right atrium, there were no other apparent metastases. Combination therapy with interferon alfa plus tegafur/uracil (UFT) was attempted with the expectation of reducing the tumor thrombus, but there was no change. Successful management was achieved with right radical nephrectomy, right auriculotomy, and partial cavectomy using cardiopulmonary bypass under high-grade hypothermia. After removal of the tumor and thrombus, blood loss was 13,900 ml during the patient's recovery. She had mild heart failure for about two weeks after the operation, but recovered. She was discharged on the 40th day after the operation. Proper preparation for blood transfusion is the key point of this operation.

Aged↗
PubMed1999

A mouse serine/threonine kinase homologous to C. elegans UNC51 functions in parallel fiber formation of cerebellar granule neurons.

The formation of the cerebellar circuitry depends on the outgrowth of connections between the two principal classes of neurons, granule neurons and Purkinje neurons. To identify genes that function in axon outgrowth, we have isolated a mouse homolog of C. elegans UNC51, which is required for axon formation, and tested its function in cerebellar granule neurons. Murine Unc51.1 encodes a novel serine/threonine kinase and is expressed in granule cells in the cerebellar cortex. Retroviral infection of immature granule cells with a dominant negative Unc51.1 results in inhibition of neurite outgrowth in vitro and in vivo. Moreover, infected neurons fail to express TAG-1 or neuron-specific beta-tubulin, suggesting that development is arrested prior to this initial step of differentiation. Thus, Unc51.1 signals the program of gene expression leading to the formation of granule cell axons.

Amino Acid Sequence↗
PubMed1999

Persistently high Epstein-Barr virus (EBV) loads in peripheral blood lymphocytes from patients with chronic active EBV infection.

Chronic active Epstein-Barr virus infection (CAEBV) is a severe illness with unusual EBV activation that persists for years, and its pathogenesis is largely unknown. After the creation of an accurate and reproducible polymerase chain reaction system to quantify EBV DNA, virus loads in peripheral blood lymphocytes (PBL) were determined in 54 children: 15 with CAEBV, 16 with infectious mononucleosis (IM), and 23 healthy children. Children with CAEBV and those with IM had high virus loads. Lower loads were detected in 47% of seropositive healthy donors. There were two distinct differences between children with CAEBV and those with IM: The former had greater viral replication (10(3)-10(7) copies/2.5x10(5) PBL) than those with IM, and viral replication declined in children with IM whereas active replication persisted for years in subjects with CAEBV. Persisting high virus loads are a possible diagnostic criterion for CAEBV. EBV loads may enable classification and prognosis of EBV infections.

Adolescent↗
PubMed1998

Identification of mouse ULK1, a novel protein kinase structurally related to C. elegans UNC-51.

A novel protein kinase related to the C. elegans serine/threonine kinase UNC-51 was cloned from mouse. The UNC-51-Like Kinase (ULK)1 is encoded by a cDNA of 1051 amino acids with calculated MW of 113 kDa. Comparison of the ULK1 and UNC-51 shows the highest conservation in the amino-terminal kinase domain, which is followed by a proline/serine-rich (PS) domain and a conserved carboxyl-terminal (C) domain. ULK1 mRNA is expressed in various tissues, and is mapped to mouse chromosome 5F and rat chromosome 12q16.3, by fluorescent in situ hybridization. HA-tagged ULK1 is expressed as a protein of approximately 150 kDa in COS7 cells and is auto-phosphorylated in vitro in its PS domain. We propose that ULK1, UNC-51 and a yeast protein kinase Apg1p comprise a novel subfamily of protein kinase, which is structurally conserved among eukaryotes.

Amino Acid Sequence↗
PubMed1998

Focal pachypolymicrogyria in three siblings.

The malformation of focal pachypolymicrogyria might be the manifestation of an X-linked recessive disorder according to the results of this study. Three siblings revealed focal pachypolymicrogyria on magnetic resonance imaging (MRI) and had a strong family history of epilepsy and mental retardation. All three siblings had the same mother; the father of Patient 1 was not related to the mother, but the father of Patients 2 and 3 was related to her. The MRI of the father of Patients 2 and 3 demonstrated focal pachypolymicrogyria. The mother's MRI was normal. In this family, epilepsy or mental retardation was found mainly in the males (Patient 3 was an exception), and they were all born to female members of this family, not male. Patient 3 was probably a homozygote with an X-linked recessive inheritance, and therefore, she demonstrated the most severe clinical findings.

Adolescent↗
PubMed1998

Primary changes in liver damage by aspirin in rats.

BACKGROUND: It has been known that acetylsalicylic acid (ASA) causes liver cell damage, however, its mechanisms remain obscure. METHODS AND RESULTS: To clarify the earliest change in the course of liver cell damage induced by oral administration of ASA, rats that had received ASA at 50 mg/kg and 150 mg/kg bodyweight orally for 7 days were investigated. Mitochondria were isolated for measurements of mitochondrial respiration, and for electron microscopic observations, small pieces of liver were excised and fixed. Uncoupling of oxidative phosphorylation was observed in mitochondria isolated from ASA-treated rats. Although no histological changes were evident, lamellar structures in bile canaliculi were ultrastructurally observed in all rats treated with ASA. CONCLUSIONS: This laminar structure, which is negative for bilirubin staining, seems to be one of the most sensitive indicators of ASA-induced liver damage.

Administration, Oral↗
PubMed1998

[The efficacy of re-TUR after 3 weeks of initial TUR treatment for locally advanced bladder cancer].

BACKGROUND: Radical cystectomy was usually performed for the patient with advanced bladder cancer. The choice of surgical procedure whether bladder preserved therapy or radical cystectomy has sometime plagued us in bladder cancer treatment. Because we don't have clear guideline for the treatment of locally advanced bladder cancer (T2-T3a N0M0). We devised a radical treatment for the patients with locally advanced bladder cancer without radical cystectomy. PATIENTS AND METHODS: We performed re-TUR treatment after 3 weeks of initial TUR for 13 patients with grade 2 and locally advanced bladder cancer diagnosed with pelvic CT scan, transurethral ultrasonography or bimanual examination under the anesthesia. RESULTS: We could successfully preserve all cases of bladder with the use of this devised TUR (periods 9-45 months median 22 months). This method has significantly reduced the cystectomy rate in such locally advanced cases compared with the cystectomy rate prior to 1993 (p < 0.001). CONCLUSION: This method has significance on treatment for locally advanced papillary bladder cancer as bladder preserving therapy with careful observation.

Aged↗
PubMed1998

[A case of multiple organ failure with massive intestinal bleeding caused by methicillin-resistant Staphylococcus aureus in a postcystectomy patient--efficacy of mask continuous positive airway pressure training and intraarterial embolization].

A 51-year-old man underwent radical cystectomy with tubeless cutaneous ureterostomy. Methicillin-resistant Staphylococcus aureus (MRSA) enteritis developed postoperatively. MRSA caused critical infections such as pneumonia and sepsis, which subsequently progressed to adult respiratory distress syndrome, massive melena and multiple organ failure. The patient was rescued by intensive management including mask continuous positive airway pressure, systemic vancomycin administration and intraarterial embolization to stop jejunal bleeding.

Carcinoma, Transitional Cell↗
PubMed1997

Induction of protein tyrosine phosphatase epsilon transcripts during NGF-induced neuronal differentiation of PC12D cells and during the development of the cerebellum.

We have investigated a possible role played by protein tyrosine phosphatase epsilon (PTPepsilon), which was recently cloned and predominantly expressed in brain, in neural differentiation and function. During neuronal cell differentiation of PC12D cells triggered by NGF or FGF, PTPepsilon transcripts were transiently induced at a time between the appearance of transcripts for immediate-early genes and for neuronal cell-specific markers. PTPepsilon was the only PTPase whose transcripts were induced during PC12D cell differentiation among over two dozen PTPase transcripts so far examined. Moreover, in situ hybridization revealed that PTPepsilon transcripts were detected in the neural tube of day 12 postcoitum embryo, and in the nervous system including brain, spinal cord, and ganglions in a ubiquitous manner in late gestational stages. In 4-day-old neonatal mice, the transcripts were widely distributed in the central nervous system where the strongest expression was detected in the hippocampus, cerebral cortex, and olfactory bulb. Interestingly, in day 7 and 16 neonatal brains, the strongest PTPepsilon gene expression was localized in the granular cells of cerebellum, which might indicate that PTPepsilon is involved in the differentiation of the granular cells. The biological significance of PTPepsilon in neuronal differentiation and brain functions is discussed.

Animals↗
PubMed1997

Identification of a receptor-type protein tyrosine phosphatase expressed in postmitotic maturing neurons: its structure and expression in the central nervous system.

We have isolated a rat cDNA encoding a receptor-type protein-tyrosine-phosphatase (RTP) expressed in brain and kidney (RPTP-BK) and characterized its expression in the developing central nervous system. RPTP-BK has seven fibronectin type III-like repeats in the extracellular region and a unique catalytic phosphatase domain in the cytoplasmic region. Bacterial expression of its phosphatase domain showed that the dephosphorylation of phosphotyrosine residues was mediated by the cytoplasmic catalytic domain. Sequence comparison revealed that RPTP-BK is homologous with GLEPP1, a rabbit PTP expressed in renal glomerular epithelia, and has the same phosphatase domain as murine PTPphi expressed in macrophages. RPTP-BK has also significant homology with Drosophila DPTP10D in the phosphatase domain, whose expression is localized exclusively in growth cones of the embryonal brains. The gene for RPTP-BK is well conserved among other species, and the expression in the brain but not in the kidney is developmentally regulated during the neonatal stage. Hybridization in situ showed that RPTP-BK is highly expressed in the postmitotic maturing neurons of the olfactory bulb, developing neocortex, hippocampus and thalamus. Because the expression of RPTP-BK in the developing neocortex is correlated with the stage of axonogenesis in cortical neurons, RPTP-BK might be crucial in neural cell development of the mammalian central nervous system.

Amino Acid Sequence↗
PubMed1997

Two primary doses of diphtheria-tetanus-acellular pertussis vaccine induce immunological responses to Bordetella pertussis as strong as those induced by three primary doses.

Pertussis vaccinations are administered worldwide under various conditions and schedules with diphtheria-tetanus-pertussis (DTP). In Japan, a general vaccination with three primary doses of diphtheria-tetanus-acellular pertussis (DTaP) at 4-week intervals and one booster dose 12 months after the primary series have been used since 1981. Decreasing the number of doses of the vaccination would lessen the physical and economic costs. To compare the immunological response to two versus three primary doses, we assessed antibody and cellular immune responses in health children. The anti-filamentous hemagglutinin (anti-FHA) and anti-pertussis toxin (anti-PT) antibody responses to two primary doses of DTaP before a booster were significantly lower than the responses to three primary doses. Although these antibody levels were low in children who received two primary doses, the FHA-induced DNA synthesis was equal to that of the children who received three doses. The anti-FHA and anti-PT antibody levels 4 weeks after the booster following two doses were similar to the levels following three doses, and high antibody titers were maintained over a long period. In areas where contact with bacteria is expected, two primary doses of DTaP may be adequate to induce the necessary level of immunological responses.

Adhesins, Bacterial↗
PubMed1997

A chimeric serine/threonine kinase receptor system reveals the potential of multiple type II receptors to cooperate with transforming growth factor-beta type I receptor.

Receptor-type serine/threonine kinases (RSKs) have been organized into two distinct classes known as types I and II on the basis of sequence similarity. However, experiments have shown ligand specificities in the two classes and as a result type I and type II receptors can often bind to a common ligand. The transforming growth factor-beta- (TGF-beta) specific receptors represent such a case, where both type I and II receptors (T beta RI and T beta RII) are observed. Of additional interest is the observation that heteromeric associations of type I and II receptors can also enable signaling. To further elucidate the function of various RSKs, the extracellular domains of both alpha and beta chains from human granulocyte-macrophage colony-stimulating factor receptors were linked to transmembrane cytoplasmic domains of RSKs. Chimeric receptors of human granulocyte-macrophage receptor (hGMR) alpha with T beta RI and hGMR beta with T beta RII were expressed in murine pre-B cell-derived Ba/F3 cells. These chimeras formed heteromeric complexes, transmitted TGF-beta signals, and were down-modulated in response to human granulocyte-macrophage colony-stimulating factor. However, experiments utilizing these chimeric receptors in different combinations revealed that only heteromeric associations of transmembrane cytoplasmic domains mediated signaling and down-modulation. Chimeric receptors with transmembrane cytoplasmic domains of activin receptor type II and bone morphogenetic protein receptor type II also provided signals in conjunction with chimeric T beta RI. As a result, these type II receptors may share a common potential to signal via T beta RI. hGMR-RSK chimeric receptors may be useful tools for the identification and characterization of the divergent signals mediated by individual RSKs.

Activin Receptors, Type I↗
PubMed1997

Reflex sympathetic dystrophy in childhood: a case report.

A case report is presented of a 15-year-old girl with reflex sympathetic dystrophy (RSD). She was referred to hospital because of left upper limb pain. Her left upper limb was cold, edematous and blue with a limited active range of movement. The serum concentration of noradrenaline was lower on the painful side than on the healthy side, and neurotropin, which has an antinociceptive effect to hyperalgesia, was clearly effective. Early diagnosis and management is essential in the treatment of RSD and administration of neurotropin is a useful and non-invasive treatment without severe adverse effects.

Adolescent↗