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Katsuya Yamamoto

Publications and source records attributed to Katsuya Yamamoto.

At least 19 recordsLinked to original sources
PubMed2006

Isodicentric Philadelphia chromosome in acute lymphoblastic leukemia with der(7;12)(q10;q10).

We describe here the first case of acute lymphoblastic leukemia (ALL) with an isodicentric Philadelphia [idic(Ph)] chromosome. A 35-year-old man was diagnosed as ALL because of the infiltration of CD10(+)CD19(+)CD33(+)CD34(+) lymphoblasts in the bone marrow and the expression of p190-type BCR/ABL fusion transcript. Chromosome analysis showed 45,XY,der(7;12)(q10;q10),der(9)t(9;22)(q34;q11),idic der(22)t(9;22)(q34;q11). The idic(Ph) chromosome was spindle-shaped and supposed to be formed by two Ph chromosomes joined at their q terminals, whereas idic(Ph) chromosomes in chronic myelogenous leukemia (CML) have been shown to be fused at the satellite regions of p arms. The results indicate that the structure of idic(Ph) chromosomes appears to be different between ALL and CML. The patient did not respond to any chemotherapy and could not achieve remission. This chromosome aberration in ALL may suggest poor prognosis as observed in some cases of CML. Furthermore, considering other three reported cases, der(7;12)(q10;q10) may be one of the recurrent translocations in ALL.

Adult↗
PubMed2006

High-performance polymer-based monolithic capillary column.

In this report, we introduce a new entry of high-performance polymer-based monolithic capillary column for mainly small molecules. This capillary column was prepared using a newly introduced epoxy monomer with diamines. Simply heat-induced polycondensation in an appropriate porogenic solvent afforded a really homogeneous co-continuous monolithic structure having submicrometer-size skeletons with micrometer-size through-pores. We were also able to prepare chiral monolithic columns using a chiral epoxy monomer as well as a chiral diamine. A 21.5-cm-long, 100-mum-i.d. column afforded up to 40 000 theoretical plate numbers (N) for alkylbenzenes in 60% aqueous acetonitrile as a reversed-phase-mode stationary phase. Due to a quite low column pressure drop, a 150-cm-long column was prepared. This long column afforded up to 200 000 plates for alkylbenzenes with only a 4-MPa column pressure drop. In contrast, in 100% acetonitrile, this column has "HILIC" property to show up to 60 000 plates for methanol with a 17.5-cm-long column. In this mode, we were able to separate nucleic acids. In addition, we have prepared a chiral column with both of the chiral epoxy monomers and an amine. This column was able to chirally discriminate a racemic alcohol in a reversed-phase mode.

Journal Article↗
PubMed2006

A biphenotypic transformation of 8p11 myeloproliferative syndrome with CEP1/FGFR1 fusion gene.

We describe here the first case of 8p11 myeloproliferative syndrome (EMS) with t(8;9)(p11;q33), who unusually demonstrated B-lymphoblastic/monoblastic biphenotypic transformation. A 57-year-old woman was admitted because of leukocytosis and diagnosed as EMS. Bone marrow was infiltrated with myeloperoxidase (MPO)-, CD10+, CD19+, CD20+, CD34+, HLA-DR+ small lymphoblasts and MPO+, CD2+, CD4+, CD13+, CD14+, CD33+, HLA-DR+ large monoblasts. The karyotype was 46,XX,t(8;9)(p11;q33)[20] and the CEP1/FGFR1 fusion transcript between CEP1 exon 38 and FGFR1 exon 9 was detected. This case clearly indicates that the blastic transformation in EMS with t(8;9) could arise in the stem cells, which differentiate into not only myelomonocytic but also B-lymphocytic lineages.

Base Sequence↗
PubMed2005

Casein kinase Iepsilon down-regulates phospho-Akt via PTEN, following genotoxic stress-induced apoptosis in hematopoietic cells.

Here, we show a functional role of casein kinase I (CKI) epsilon in hematopoietic cell survival through the modification of phosphatidylinositol 3-kinase (PI3K)/Akt signaling. Introduction of wild-type (WT)-CKIepsilon into interleukin-3 (IL-3)-dependent 32D cells increased the sensitivity to genotoxic stresses, such as gamma-irradiation, etoposide, and IL-3 deprivation, whereas kinase-negative (KN)-CKIepsilon suppressed it. Contrary to KN-CKIepsilon, WT-CKIepsilon attenuated the IL-3-induced activation of Akt with the increase of PTEN activity. Similarly, the increase of Akt activation, as well as PTEN inactivation, was accompanied both by a decrease of CKIepsilon expression induced by all-trans retinoic acid and by the addition of a specific inhibitor for CKIepsilon in HL-60 cells. CKIepsilon seems to activate PTEN by physical interaction. These results suggest that the CKIepsilon-induced down-regulation of PI3K/Akt signaling through PTEN lead to amplified sensitivity to apoptosis. Thus, the suppression of CKIepsilon in many human leukemia cell lines may play a role in the cell immortalization.

Animals↗
PubMed2005

A der(13)t(7;13)(p13;q14) with monoallelic loss of RB1 and D13S319 in myelodysplastic syndrome.

Deletions or translocations of chromosome band 13q14, the locus of the retinoblastoma gene (RB1), have been observed in a variety of hematological malignancies including myelodysplastic syndrome (MDS). We describe here a novel unbalanced translocation der(13)t(7;13)(p13;q14) involving 13q14 in a patient with MDS. A 66-year-old woman was diagnosed as having MDS, refractory anemia with excess of blasts (RAEB-1) because of 7.4% blasts and trilineage dysplasia in the bone marrow cells. G-banding and spectral karyotyping analyses showed complex karyotypes as follows: 46,XX,der(6)t(6;7)(q11;?),der(7)del(7)(?p13)t(6;7)(q?;q11)t(6;13)(q?;q?),der(13)t(7;13)(p13;q14). Fluorescence in situ hybridization (FISH) analyses demonstrated that one allele of the RB1 gene and the microsatellite locus D13S319, located at 13q14 and telomeric to the RB1 gene, was deleted. Considering other reported cases, our results indicate that submicroscopic deletions accompanying 13q14 translocations are recurrent cytogenetic aberrations in MDS. The RB1 gene or another tumor suppressor gene in the vicinity of D13S319, or both, may be involved in the pathogenesis of MDS with 13q14 translocations by monoallelic deletion.

Aged↗
PubMed2005

Therapy-related myelodysplastic syndrome with inv(16)(p13q22) and I type CBFbeta/MYH11 after autologous transplantation: undetectable fusion transcript in pretransplant progenitor cells.

We describe here a unique case of therapy-related myelodysplastic syndrome (t-MDS) with inv(16)(p13q22) after autologous stem cell transplantation for lymphoma. The rare and smallest I type CBFbeta/MYH11 fusion transcript with a breakpoint at nucleotide 399 of CBFbeta and at nucleotide 2134 of MYH11 was detected in the bone marrow cells by reverse transcription polymerase chain reaction analysis. However, the fusion transcript was undetectable in the pretransplant peripheral blood stem cells. These results suggest that the stem cell damage leading to t-MDS may be induced mainly by the conditioning regimen for transplantation. Taken together with previous reports, the I type fusion transcript is preferentially induced with chemotherapy.

Chromosomes, Human, Pair 16↗
PubMed2005

Opercular to interhemispheric source distribution of benign rolandic spikes of childhood.

We evaluated the source distribution of benign rolandic spikes of childhood along and across the central sulcus in 15 patients, aged between 7 and 15 years, who suffered from seizure disorders. Previous routine EEG showed centrotemporal spikes, but none of them had major abnormalities on brain magnetic resonance imaging or neurological deficits. The equivalent current dipoles (ECDs) of the spikes measured by whole-head magnetoencephalography (MEG) were compared to the spike distributions detected by simultaneous scalp EEG according to the international 10-20 system. Locations and orientations of the MEG spikes corresponded to the EEG spike distribution as follows: superiorly oriented spike MEG dipoles in the opercular area corresponded to T3/4 negative peaks (8 spike groups in 6 patients); anteriorly oriented spike dipoles in the rolandic area corresponded to C3/4 or P3/4 negative peaks (17 spike groups in 13 patients); laterally oriented spike dipoles in the interhemispheric area corresponded to Cz/Pz negative peaks (4 spike groups in 3 patients); and others (4 spike groups in 4 patients). Rolandic spikes include three main types according to the ECD location from the opercular to the interhemispheric areas. The functional anatomy of benign rolandic spikes was correlated with partial seizure semiology. All three rolandic spike types can be explained by a precentral origin, assuming that the surface negative potential is continuous from the gyral to fissural cortices.

Adolescent↗
PubMed2005

The role of transcriptional coactivator TRAP220 in myelomonocytic differentiation.

The TRAP220 subunit of the thyroid hormone receptor-associated polypeptide transcription coactivator complex (TRAP/Mediator complex), mammalian counterpart of the yeast Mediator complex, is proposed to act on a variety of major and specific biological events through physical interactions with nuclear receptors. The vitamin D receptor (VDR) and retinoic acid receptor (RAR), coupled with retinoid X receptor (RXR), are nuclear receptors which have important roles for monopoiesis and granulopoiesis, respectively. In this study, we present the functional role of TRAP220 in nuclear receptor-mediated monopoiesis and granulopoiesis. The mouse Trap220(-/-) yolk sac hematopoietic progenitor cells were resistant to 1,25-dihydroxyvitamin D(3)-stimulated differentiation into monocytes/macrophages. Furthermore, flow cytometric analyses showed that HL-60 cells, human promyelocytic leukemia cell line, wherein TRAP220 was down-regulated, did not differentiate efficiently into monocytes and granulocytes by stimulation with 1,25-dihydroxyvitamin D(3) and all-trans retinoic acid, correspondingly. The expression of direct target genes of VDR or RAR, as well as the differentiation marker genes, was low in the knockdown cells. These results indicated a crucial role of TRAP220 in the optimal VDR- and RAR-mediated myelomonocytic differentiation processes in mammalian hematopoiesis.

Animals↗
PubMed2005

Successful treatment with defibrotide for sinusoidal obstruction syndrome after hematopoietic stem cell transplantation.

Sinusoidal obstruction syndrome (SOS) (formerly known as hepatic veno-occlusive disease (VOD)) is a life-threatening complication subsequent to hematopoietic stem cell transplantation. However, no completely satisfactory strategies for the treatment of SOS have been established yet. Defibrotide is a single-stranded polydeoxyribonucleotide with anti-thrombotic, anti-ischemic, anti-inflammatory and thrombolytic properties, but without systemic anticoagulant effects, and some encouraging results have been reported in western countries. We treated four patients with defibrotide for SOS, since there seemed to be no possibility to cure the patients with conventionally available treatments in Japan. All patients showed evidence of multiple organ failure at the start of the treatment. Defibrotide was administered intravenously in normal saline in four divided doses for 14 to 27 days. Three patients (75%) responded to the therapy, while one died of SOS and cytomegalovirus infection despite intensive therapy. None of the patients suffered from significant adverse effects such as severe hemorrhage. This is the first report dealing with the treatment with defibrotide of Japanese patients with SOS. Because defibrotide is considered to be promising for the treatment of SOS, it is important to start a phase II study as soon as possible.

Adult↗
PubMed2004

Hydrocephalus due to cerebrospinal fluid overproduction by bilateral choroid plexus papillomas.

CASE REPORT: A 10-month-old boy, with congenital deafness and blindness associated with chromosomal deletion [46XY, del(13)(q32)], presented with intractable ascites 9 months after ventriculo-peritoneal shunting for congenital hydrocephalus. Revision of the ventriculo-atrial shunt resulted in shunt failure 1 month later. External ventricular drainage revealed cerebrospinal fluid (CSF) overproduction (2,000 ml/day). Magnetic resonance imaging showed marked lobular enlargement of the bilateral choroid plexuses extending from the trigone to the body and inferior horn of the lateral ventricle. Multi-staged resection was performed via bilateral temporo-occipital transcortical approaches, and CSF production significantly decreased to 100 ml/day postoperatively. Histological assessment of the villous surface suggested villous hyperplasia of the choroid plexus and thorough evaluation including the proximal portion of the lobular lesion near the attachment revealed choroid plexus papilloma. He was discharged after ventriculo-peritoneal shunting without additional neurological deficits except for hyperreflexia of the left extremities. CONCLUSION: CSF overproduction caused by bilateral choroid plexus papillomas can result in hydrocephalus. Radical resection of the bilateral ventricular lesions should be considered for this entity. Thorough evaluation of the surgical specimen is recommended because histological examination of only the lobular surface of the choroid plexus lesion may fail to identify choroid plexus neoplasm.

Cerebrospinal Fluid↗
PubMed2004

Unbalanced translocation der(11)t(11;12)(q23;q13): a new recurrent cytogenetic aberration in myelodysplastic syndrome with a complex karyotype.

Cytogenetic abnormalities are observed in approximately one half of cases of myelodysplastic syndrome (MDS). Partial or complete chromosome losses and chromosome gains are frequently found, but there is a relatively high incidence of unbalanced translocations in MDS. We describe here two cases of MDS with an unbalanced translocation, der(11)t(11;12)(q23;q13). Both patients were 69 years of age and diagnosed with refractory anemia with excess of blasts in transformation (RAEB-t) according to the high percentage of blasts in the peripheral blood. Cytoplasmic hypogranulation of neutrophils was evident as a dysplastic change. The blasts were positive for CD4 and CD41a as well as CD13, CD33, CD34 and HLA-DR in both cases. Chromosome analysis showed complex karyotypes including a der(11)t(1;11)(q11;p15)t(11;12)(q23;q13) in case 1 and der(11)t(11;12)(q23;q13) in case 2 plus several marker chromosomes. Spectral karyotyping confirmed the der(11)t(11; 12)(q23;q13) and clarified the origin of marker chromosomes, resulting in del(5q) and del(7q). Fluorescence in situ hybridization (FISH) analyses with a probe for the MLL gene demonstrated that the breakpoints at 11q23 were telomeric to the MLL gene in both cases. FISH also showed that the breakpoint at 11p15 of the case 1 was telomeric to the NUP98 gene. Considering another reported case, our results indicate that the der(11)t(11;12)(q23;q13) is a recurrent cytogenetic abnormality and may be involved in the pathogenesis of advanced-stage MDS.

Aged↗
PubMed2004

[Survey of vaccination and viral infections for children with severe myoclonic epilepsy in infancy].

A study group for establishment of a proposed immunization program for neurologically high risk children (Chief, Kihei Maekawa) sponsored by the Ministry of Health, Labour and Welfare of Japan is preparing a proposal for patients with epilepsy. Severe myoclonic eplepsy in infancy (SMEI) is an intractable epilepsy which often presents with status epilepticus and triggered by hyperthermia and viral infections. In this study we investigated the history of vaccination in children with SMEI to compare the risk of vaccination with that of natural contraction of infection. Fifty-eight patients with SMEI, aged from 2 to 25 years, were enrolled in this study. A total of 359 vaccines were given to these subjects. The vaccination rates were high for BCG (71%) and polio (1st; 71%, 2nd; 53%), and then fell gradually after the onset of SMEI (DPT-1st; 48%. DPT-2nd; 45%, DPT-3rd; 38%, DPT-4th; 24%, mumps; 21%, varicella; 19%, rubella 31%). However, the measles vaccine was given at a relatively high rate (55%) before the age of three. When patients suffered from measles, rubella, mumps or influenza, they had a high risk of severe neurological complications, such as convulsive status, disturbance of consciousness and encephalopathy. These complications were documented in 63% of all episodes of naturally contracted infections. This rate was significantly higher (p < 0.0001) than that associated with vaccination (7.2%). However, hyperthermia and convulsion developed more frequently (p = 0.012) after measles vaccine was given, as compared to other vaccines. Thus, administration of these vaccines to patients with SMEI in conjunction with other preventive measures against seizure induced by hyperthermia, may meet the needs of their parents.

Adolescent↗
PubMed2003

Breast cancer with endocrine differentiation: report of two cases showing different histologic patterns.

We report two cases of breast cancer with endocrine differentiation. Case 1 was a 56-year-old woman with a 2-cm tumor in the upper outer quadrant of the right breast and right axillary lymphadenopathy. Excisional biopsy suggested carcinoma and we performed breast-conserving surgery with lymph node dissection. Histologic examination revealed breast cancer with endocrine differentiation resembling small cell carcinoma of the lung, with one nodal metastasis. Case 2 was a 71-year-old woman with a 2.5-cm tumor in the upper outer quadrant of the right breast. Aspiration cytology suggested carcinoma and we performed mastectomy with lymph node dissection. Histologic examination revealed a carcinoid tumor, as one of the breast cancers with endocrine differentiation, but no nodal metastasis. The two patients are now disease-free 26 and 12 months after surgery, respectively.

Aged↗
PubMed2003

A novel t(2;6)(p12;q23) appearing during transformation of follicular lymphoma with t(18;22)(q21;q11) to diffuse large cell lymphoma.

Follicular lymphoma is characterized genetically by t(14;18)(q32;q21), whereas t(18;22)(q21;q11), a rare variant form of t(14;18), has been preferentially observed in chronic lymphocytic leukemia (CLL). We describe here an unusual case of follicular lymphoma with a t(18;22)(q21;q11), that progressed to diffuse large cell lymphoma with a novel t(2;6)(p12;q23). Spectral karyotyping revealed that add(2)(p12) and add(6)(q23) were derived from a t(2;6)(p12;q23). Fluorescence in situ hybridization analysis confirmed rearrangements of the BCL2 gene at 18q21 and the BCL6 gene at 3q27. Our results indicate that a reciprocal translocation involving 6q23 could be implicated in the progression of follicular lymphoma and that t(18;22) may have a specific role in the pathogenesis of follicular lymphoma as well as CLL.

Adult↗
PubMed2003

Effective anti-viral therapy for hemophagocytic syndrome associated with B-cell lymphoma.

A rheumatoid arthritis (RA) patient treated with low-dose methotrexate (MTX) therapy suffered from hemophagocytic syndrome (HPS) associated with B-cell lymphoma (B-LAHS). Administration of acyclovir and intravenous immunoglobulin promptly resolved laboratory test abnormalities accompanied with HPS. Moreover, hemophagocytic histiocytes and lymphoma cells in the bone marrow disappeared without anti-cancer therapy. Two months after reintroduction of MTX for RA flare, lymphoma re-grew rapidly without bone marrow involvement and HPS. Two cycles of combination chemotherapy induced the lymphoma to a complete remission/unconfirmed (CRu), but then the chemotherapy was discontinued due to severe side effects. In this case, on the basis of RA and MTX induced immunosuppressive state, Epstein-Barr virus (EBV) infection was associated with the development of HPS and lymphoma. Anti-viral therapy alone was effective against HPS and lymphoma at initial presentation and improved her general condition. This case indicates that anti-cancer therapy should be preceded by anti-viral therapy and withdrawal of immunosuppressive therapy in patients under immunosuppressive therapy, as long as the clinical situation permits.

Acyclovir↗
PubMed2003

Morphologic, flow cytometric and cytogenetic evaluation of bone marrow involvement in B-cell lymphoma.

BACKGROUND AND OBJECTIVES: Flow cytometric immunophenotypic analysis (FC) and cytogenetic analysis are essential techniques for the diagnosis and classification of many hematologic disorders. The roles of these analyses in B-cell lymphoma to detect bone marrow (BM) involvement in clinical staging and to evaluate the effectiveness of treatments have not yet been determined. The aim of this study was to evaluate the usefulness of FC and cytogenetic analysis in the assessment of BM involvement in B-cell lymphoma. DESIGN AND METHODS: We retrospectively analyzed the usefulness of three-color FC and cytogenetic analysis in detecting BM involvement by examining 104 BM specimens from patients with B-cell lymphoma. RESULTS: By morphologic evaluation of BM biopsy (BMB), the BM was involved in 11 specimens (10.6%), not involved in 92 specimens (88.5%) and involvement could not be determined in 1 specimen (0.9%). FC identified a monoclonal B-cell population in 24 samples (23.1%). FC detected BM involvement in all but one BMB positive sample, and showed negative results in a BMB undetermined sample. Conclusively, FC found a monoclonal B-cell population in 14 of 92 BMB negative samples (15.2%). In particular, FC detected smaller amounts of BM involvement than did morphologic evaluation. Cytogenetic analysis revealed clonal abnormalities in only 9 of 104 samples (8.7%). However, 2 of these 9 samples were from patients with aggressive lymphoma with complex structural chromosomal abnormalities detectable only by cytogenetic analysis. INTERPRETATION AND CONCLUSIONS: Although morphologic evaluation of adequate amounts of BMB specimens remains essential for the evaluation of BM involvement, three-color FC is more sensitive in detecting BM disease than morphologic or cytogenetic analysis. Cytogenetic analysis seems to have low sensitivity and specificity, but this method may improve the detection of BM involvement in a small number of aggressive lymphomas that have many mitotic cells.

B-Lymphocytes↗