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J Ota

Publications and source records attributed to J Ota.

At least 19 recordsLinked to original sources
PubMed2004

DNA microarray analysis of natural killer cell-type lymphoproliferative disease of granular lymphocytes with purified CD3-CD56+ fractions.

Natural killer (NK) cell-type lymphoproliferative disease of granular lymphocytes (LDGL) is characterized by the outgrowth of CD3(-)CD16/56(+) NK cells, and can be further subdivided into two distinct categories: aggressive NK cell leukemia (ANKL) and chronic NK lymphocytosis (CNKL). To gain insights into the pathophysiology of NK cell-type LDGL, we here purified CD3(-)CD56(+) fractions from healthy individuals (n=9) and those with CNKL (n=9) or ANKL (n=1), and compared the expression profiles of >12 000 genes. A total of 15 'LDGL-associated genes' were identified, and a correspondence analysis on such genes could clearly indicate that LDGL samples share a 'molecular signature' distinct from that of normal NK cells. With a newly invented class prediction algorithm, 'weighted distance method', all 19 samples received a clinically matched diagnosis, and, furthermore, a detailed cross-validation trial for the prediction of normal or CNKL status could achieve a high accuracy (77.8%). By applying another statistical approach, we could extract other sets of genes, expression of which was specific to either normal or LDGL NK cells. Together with sophisticated statistical methods, gene expression profiling of a background-matched NK cell fraction thus provides us a wealth of information for the LDGL condition.

Adolescent↗
PubMed2003

DNA microarray analysis of hematopoietic stem cell-like fractions from individuals with the M2 subtype of acute myeloid leukemia.

Acute myeloid leukemia (AML) may develop de novo or secondarily to myelodysplastic syndrome (MDS). Although the clinical outcome of MDS-related AML is worse than that of de novo AML, it is not easy to differentiate between these two clinical courses without a record of prior MDS. Large-scale profiling of gene expression by DNA microarray analysis is a promising approach with which to identify molecular markers specific to de novo or MDS-related AML. This approach has now been adopted with AC133-positive hematopoietic stem cell-like fractions purified from 10 individuals, each with either de novo or MDS-related AML of the M2 subtype. Sets of genes whose activity was associated with either disease course were identified. Furthermore, on the basis of the expression profiles of these genes, it was possible to predict correctly the clinical diagnosis for 17 (85%) of the 20 cases in a cross-validation trial. Similarly, different sets of genes were identified whose expression level was associated with clinical outcome after induction chemotherapy. These data suggest that, at least in terms of gene expression profiles, de novo AML and MDS-related AML are distinct clinical entities.

Antigens, CD↗
PubMed2003

[Repair for atrioventricular valve regurgitation using autologous pericardium: report of a case].

A 13-year-old boy with [SLL] single left ventricle first underwent ventricular septation using a dacron patch at 3 years of age. Eight years after the first surgery, he presented with general fatigue on exertion as the chief complaint. Right-sided atrioventricular valve regurgitation, and dilatation of the right heart were diagnosed. Eleven years after surgery, right heart failure was uncontrollable by medicine, and 2nd surgery was performed. At operation, the right-sided heart valve leaflet was tightly adherent to the dacron septation patch, and valve plasty was judged impossible. We repaired the right-sided atrioventricular valve using an autologous pericardial valve leaflet and sub-valvular tissue. The postoperative course was uneventful, and he has been free from any complication for 33 months.

Adolescent↗
PubMed2002

[Extracardiac fontan procedure in adult: report of a case].

We report a case of a 28-year-old female who underwent an extracardiac Fontan procedure. The subject was diagnosed as an atrioventricular septal defect (Rastelli classification: type C), a double outlet right ventricle, pulmonary artery stenosis, a hypoplasty of left ventricle, total anomalous venous return (Darling: Ib + IIb), and atrial flutter. She underwent a Blalock shunt and an aorto-pulmonary shunt at the ages of 3 and 9 years, respectively. Under a total CPB, an extracardiac total cavo-pulmonary connection (TCPC), using a 26 mm Hemashield graft, was completed. The postoperative course was uneventful. The complicated atrial anatomy and atrial arrhythmia indicated TCPC in this adult patient.

Adult↗
PubMed2001

Characterization of stage progression in chronic myeloid leukemia by DNA microarray with purified hematopoietic stem cells.

Chronic myeloid leukemia (CML) is characterized by the clonal expansion of hematopoietic stem cells (HSCs). Without effective treatment, individuals in the indolent, chronic phase (CP) of CML undergo blast crisis (BC), the prognosis for which is poor. It is therefore important to clarify the mechanism underlying stage progression in CML. DNA microarray is a versatile tool for such a purpose. However, simple comparison of bone marrow mononuclear cells from individuals at different disease stages is likely to result in the identification of pseudo-positive genes whose change in expression only reflects the different proportions of leukemic blasts in bone marrow. We have therefore compared with DNA microarray the expression profiles of 3456 genes in the purified HSC-like fractions that had been isolated from 13 CML patients and healthy volunteers. Interestingly, expression of the gene for PIASy, a potential inhibitor of STAT (signal transducer and activator of transcription) proteins, was down-regulated in association with stage progression in CML. Furthermore, forced expression of PIASy has induced apoptosis in a CML cell line. These data suggest that microarray analysis with background-matched samples is an efficient approach to identify molecular events underlying the stage progression in CML.

AC133 Antigen↗
PubMed2001

Sak serine-threonine kinase acts as an effector of Tec tyrosine kinase.

The murine sak gene encodes a putative serine-threonine kinase which is homologous to the members of the Plk/Polo family. Although Sak protein is presumed to be involved in cell growth mechanism, efforts have failed to demonstrate its kinase activity. Little has been, therefore, elucidated how Sak is regulated and how Sak contributes to cell proliferation. Tec is a cytoplasmic protein-tyrosine kinase (PTK) which becomes activated by the stimulation of cytokine receptors, lymphocyte surface antigens, heterotrimeric G protein-linked receptors, and integrins. To clarify the in vivo function of Tec, we have tried to isolate the second messengers of Tec by using the yeast two-hybrid screening. One of such Tec-binding proteins turned out to be Sak. In human kidney 293 cells, Sak became tyrosine-phosphorylated by Tec, and the serine-threonine kinase activity of Sak was detected only under the presence of Tec, suggesting Sak to be an effector molecule of Tec. In addition, Tec activity efficiently protects Sak from the "PEST" sequence-dependent proteolysis. Internal deletion of the PEST sequences led to the stabilization of Sak proteins, and expression of these mutants acted suppressive to cell growth. Our data collectively supports a novel role of Sak acting in the PTK-mediated signaling pathway.

Amino Acid Sequence↗
PubMed2001

[Not Available].

Explore the source record for details and available documents.

Journal Article↗
PubMed2000

Association of Cbl with Fms and p85 in response to macrophage colony-stimulating factor.

Tyrosine phosphorylation of Cbl and its association with signal-transducing molecules in response to macrophage colony-stimulating factor (M-CSF) were analyzed by using cell lines which express the wild-type and a mutant M-CSF receptor, Fms. We found that in a clone, F723 TF-1 cells expressing mutant Fms in which tyrosine 723 had been substituted with phenylalanine, the M-CSF stimulation-dependent association between Cbl and Fms was markedly impaired. However, phosphorylation of Cbl and its association with the p85 subunit of phosphatidylinositol 3-kinase were induced in these mutant cells as seen in the wild-type fms transfectant. These results suggest that phosphorylation of tyrosine 723 is particularly important for the recruitment of Cbl to the M-CSF receptor, but is not required for the phosphorylation and binding of Cbl to signal-transducing molecules such as p85.

Amidohydrolases↗
PubMed1999

[A late phase II clinical study of RP56976 (docetaxel) in patients with advanced or recurrent gastric cancer: a cooperative study group trial (group B)].

A late phase II clinical study of RP56976 (docetaxel) in patients with advanced or recurrent gastric cancer was performed to evaluate the anti-tumor activity and clinical toxicity as a multicenter cooperative trial. Docetaxel was administered intravenously at a dose of 60 mg/m2 every 3-4 weeks. Of 72 patients enrolled, 63 patients were eligible and 59 patients were evaluable for response. The anti-tumor effects obtained complete response (CR) in one patient partial response (PR) in 13, minor response (MR) in 3, no change (NC) in 20, and progressing disease (PD) in 22 patients. The overall response rate in 59 patients was 23.7% (14/59). For 14 CR or PR cases, a response appeared 10 to 107 days (median 33.5 days) and 1 to 8 (median 2) times of dosing after the initial administration. The response rate was 9.5% in the primary tumor, 31.3% livers, 50.0% abdominal tumor, and 24.1% lymph nodes, respectively. The major adverse reactions were gastrointestinal symptoms including nausea/vomiting, anorexia, fatigue, alopecia and fever. Leukocytopenia and neutrocytopenia were also observed with a high incidence, but they recovered after 8 days from the nadir. The results show that docetaxel is an effective anti-tumor agent for advanced or recurrent gastric cancer. It is necessary to conduct another clinical trial by concomitant administration with other anti-tumor agents.

Adenocarcinoma↗
PubMed1999

[A case of supravalvular mitral ring].

A two-year-old girl with supravalvular mitral ring successfully underwent the excision of the ring. The preoperative echocardiogram showed supravalvular mitral ring and almost normal mitral leaflets. We paid attention not to injury mitral valve at the excision of the ring because supravalvular mitral ring adhered to the mitral valve.

Child, Preschool↗
PubMed1998

Association of CrkL with STAT5 in hematopoietic cells stimulated by granulocyte-macrophage colony-stimulating factor or erythropoietin.

CrkL is an adapter protein comprising Src homology (SH) 2 and SH3 domains. We investigated the molecule(s) associated with CrkL in factor-dependent cell lines. In the granulocyte-macrophage colony-stimulating factor (GM-CSF)-dependent cell lines TF-1 and UT-7, an approximately 95-kDa tyrosine-phosphorylated protein was precipitated along with CrkL after GM-CSF stimulation. The same protein was also observed when we used the erythropoietin (EPO)-dependent cell line UT-7/EPO, in an EPO stimulation-dependent manner. We identified it as STAT5 (signal transducer and activator of transcription 5, 96 kDa) by STAT5-specific antibodies. The direct binding of the SH2 domain of CrkL to STAT5 was demonstrated in far Western blotting and pull-down experiments using the glutathione S-transferase (GST) fusion construct CrkL-SH2. The addition of the oligopeptide containing phosphotyrosine 694 in STAT5A impaired the association between GST-CrkL-SH2 and STAT5. Furthermore, in a gel shift assay using prolactin-inducible element (PIE) as the probe, the DNA binding activity of STAT5 was inhibited by the interaction with GST-CrkL-SH2 in vitro. Finally, we found that STAT5 associated with CrkL did not bind to PIE sequence. These results suggest that CrkL participates in the Janus kinase (JAK)-STAT pathway by direct association with STAT5.

Adaptor Proteins, Signal Transducing↗
PubMed1998

Identification of alternatively spliced transcripts encoding murine macrophage colony-stimulating factor.

We have isolated a novel cDNA encoding macrophage colony-stimulating factor (M-CSF) from a murine stromal cell line, ST2. The cDNA included an entire coding sequence of the M-CSF gene but contained an additional sequence of 140 base pairs (bp). Northern blot analysis demonstrated that other murine cell lines such as a fibroblastic cell line (L) and a stromal cell line (PA6) also expressed the transcripts corresponding to the clone. The nucleotide sequence analyses of the cDNA and the cloned M-CSF genome revealed that the 140-bp insertion sequence was part of intron 1 which separated exon 1 and exon 2: the former contained part of the amino acid residues of the signal sequence and the latter the rest of the signal sequence and the first 22 amino acid residues of the mature protein. The insertion of the 140-bp intron sequence not only changed the amino acid sequence of the signal peptide but also generated an in-frame termination codon. However, instead of the dysfunction of the original initiation codon, the 140-bp insertion sequence contained a putative ATG initiation codon that preserved the original open reading frame. Finally, we found that the cDNA directed the expression of a secreted and biologically active M-CSF protein when it was introduced into COS7 cells and M-CSF activity in the culture supernatants was measured using an M-CSF-dependent cell line. These results indicate the presence of an alternatively spliced M-CSF transcript which utilizes an alternate initiation codon in order to specify active M-CSF protein.

Alternative Splicing↗
PubMed1998

[An early phase II clinical study of S-1 in patients with breast cancer. S-1 Cooperative Study Group (Breast Cancer Working Group)].

An early phase II clinical study of S-1 in patients with advanced or recurrent breast cancer was undertaken by a cooperative study group (Breast Cancer Working Group) of 14 institutes in Japan. S-1 was administered twice daily at 75 or 50 mg (dose FT)/body for 28 consecutive days with 14 days rest (one course). Twenty-eight patients were enrolled, 27 were eligible for the study, and 25 were evaluable for efficacy. Four complete responses and seven partial responses were obtained, and the response rate was 40.7% (11/27) [ninety percent confidence interval for this response was 26.7-56.4%]. The major adverse reactions observed were myelosuppression represented by leukopenia 44.4% (12/27), neutropenia 40.7% (11/27), RBC decreased 37.0% (10/27), hemoglobin decreased 29.6% (8/27), anorexia 55.6% (15/27), nausea/vomiting 48.1% (13/27), and fatigue 33.3% (13/27). The results suggested that the efficacy and safety of S-1 were effective against advanced or recurrent breast cancer. The objective of study judged should be investigated in a late phase II clinical study.

Adult↗
PubMed1998

[Late phase II clinical study of RP56976 (docetaxel) in patients with advanced/recurrent gastric cancer: a Japanese Cooperative Study Group trial (group A)].

A late phase II clinical study of RP56976 (docetaxel) was conducted in patients with advanced/recurrent gastric cancer as a multicenter cooperative trial. Docetaxel was administered intravenously at a dose of 60 mg/m2 every 3-4 weeks. Of the 76 patients enrolled, 66 patients were eligible and 59 patients were evaluable for response. One patient showed complete response (CR), 13 patients partial response (PR), 1 patient minor response (MR), 19 patients no change (NC) and 25 patients had progressive disease (PD). The overall response rate in 59 evaluable patients was 23.7% (95% CI = 13.6-36.6%). The primary tumor showed a 4.3% (1/23) response, while the metastatic lesions in the abdomen, pelvic mass, lung, liver, and lymph nodes showed response rates of 62.5% (5/8), 33.3% (1/3), 33.3% (1/3), 14.8% (4/27), and 13.9% (5/26), respectively. About hematological toxicity, severe (Grade 3 or more) leukopenia was observed in 36 patients (56.3%) and neutropenia in 52 patients (81.3%). Other major toxicity (Grade 3 or more) included nausea/vomiting in 11 patients (17.2%), anorexia in 9 patients (14.1%), fatigue in 5 patients (7.8%), and alopecia in 7 patients (10.9%), all which were tolerable. The results show that docetaxel is an effective anticancer agent for advanced/recurrent gastric cancer.

Adult↗
PubMed1997

Biologic activity of proteoglycan macrophage colony-stimulating factor.

We compared the biologic activities of 85-kDa macrophage-CSF (85-kDa M-CSF), which is fully active, and a proteoglycan M-CSF (PG-M-CSF). Both originate from the same precursor, but the latter retains the carboxyl-terminal portion, which must be proteolytically removed from the precursor to generate 85-kDa M-CSF and which is uniquely modified by a chondroitin sulfate glycosaminoglycan chain. PG-M-CSF supported the formation of murine macrophage colonies such as 85-kDa M-CSF. Furthermore, PG-M-CSF stimulated the proliferation of murine bone marrow macrophages, an M-CSF-dependent murine cell line, and an M-CSF-responsive human cell line established by transfer of the human M-CSF receptor gene. PG-M-CSF and 85-kDa M-CSF had equivalent specific biologic activities on a molar basis in all bioassays. The activity of PG-M-CSF was not affected by enzymatically removing the glycosaminoglycan chain when assayed by the formation of macrophage colonies and proliferation of the bone marrow macrophages. We analyzed the phosphorylation on tyrosine residue(s) of the M-CSF receptor in response to these M-CSFs that trigger mitogenic responses. PG-M-CSF rapidly (within 10 min) induced receptor phosphorylation in human cells with the same potency as 85-kDa M-CSF. These results indicate that PG-M-CSF is not a latent form or precursor of 85-kDa M-CSF but a fully biologically active cytokine.

Animals↗
PubMed1997

[Clinical efficacy of GG032X tablets, a new dosage form of ondansetron (fast dispersing tablet), on cisplatin-induced nausea and emesis].

The inhibitory effects of GG032X tablets, a new dosage form (fast dispersing tablet) of ondansetron, 5-HT2 receptor antagonist, on nausea and emesis induced by cisplatin (CDDP), were investigated along with safety and usefulness. Subjects were chemotherapy patients starting CDDP administration for the first time, who were receiving a high single dose of CDDP (50 mg/m2 or more and intravenous drip infusion of less than 4 hours), or lower multiple doses of CDDP (a single dose of 10 mg/m2 or more, administered intravenously for 3-5 consecutive days). GG032X tablets were administered orally 1-2 hours before CDDP administration. In lower multiple doses of CDDP, GG032X tablets and CDDP were administered, as much as possible, at the same respective time when they were administered on the first day. Efficacy of GG032X tablets was evaluated in terms of inhibitory effect on nausea and emesis 24 hours after administration of a high single dose of CDDP, and of the inhibitory effect on nausea and emesis during the study period (3-5 days) in lower multiple doses of CDDP. Efficacy, safety and usefulness were evaluated in accordance with the evaluation criteria used in the clinical study of already-approved ondanstron tablets. In a high single dose of CDDP, the cases judged "effective" or better in the investigation of the inhibitory effect of the drug on nausea and emesis, accounted for 52.9% (63/119 cases). As for the overall safety rating, the cases judged as "safe" accounted for 87.0% (107/123 cases), and as a "minor safety problem" accounted for 13.0% (16/123 cases). As for the usefulness rating, the cases judged "useful" or better accounted for 52.1% (62/119 cases). Major adverse effects included headache, fever, atrial fibrillation and increases in total bilirubin, GOT and GPT values. None of these was serious, and the patients recovered without any treatment or by nosotropic therapy. Meanwhile, in lower multiple doses of CDDP, the inhibitory effect judged "effective" or better accounted for 70.6% (12/17 cases). As for the overall safety rating, all cases were judged "safe". In terms of usefulness, those cases judged "useful" or better accounted for 70.6% (12/17 cases). No adverse effect was observed. Study results of these two groups were almost the same as those for already-approved ondansetron tablets. According to the results of questionnaires for the patients who participated in the study and took GG032X tablets, the drug was found to be easy to take and had favorable results. Based on the above results, GG032X tablets were evaluated as having the same inhibitory effect as the already-approved ondansetron tablets against CDDP-induced nausea and emesis, and were considered safe and clinically useful.

Administration, Oral↗
PubMed1996

Ameloblastoma with prominent ossification in the mandible of a dog.

A rare case of ameloblastoma with prominent stromal ossification in an 8-year-old female dog was studied. A bony mass recurred rapidly in the right mandible at the first molar region. Histopathologic examination revealed the lesion to be an atypical variant of ameloblastoma. Epithelial cells showed marked cell atypia, and mitotic figures were rather common. The collagenous stroma was abundant, with prominent formation of bone trabecular rimmed by active osteoblasts. The tumor was highly proliferative and aggressive, and thought to be malignant in nature.

Ameloblastoma↗