PubMed Health⌕ Search

Biomedical subjects

O Katoh

Publications and source records attributed to O Katoh.

At least 55 records · Page 3Linked to original sources
PubMed1997

The coexistence of abdominal aortic aneurysm and advanced gastric cancer associated with recurrent angina after coronary artery bypass grafting.

A 76-year-old man with abdominal aortic aneurysm (AAA) and concomitant gastric cancer, who had undergone coronary artery bypass grafting (CABG), presented with recurrent exertional angina. Both lesions, the AAA and advanced gastric cancer, exhibited an absolute indication for urgent surgery. Coronary revascularization with percutaneous transluminal coronary angioplasty (PTCA) was carried out successfully before abdominal surgery. A one-stage abdominal operation was performed safely. The need for coronary revascularization complicates the treatment strategy for these patients with associated coronary artery disease. PTCA is the best option, especially if the patient presents with recurrent angina after prior CABG.

Aged↗
PubMed1997

c-kit Point mutation in patients with myeloproliferative disorders.

Myeloproliferative disorders (MPD) constitute a group of hematopoietic neoplasms at the myeloid stem cell level. Myeloid stem cells and/or progenitor cells from MPD have been considered sensitive to hematopoietic growth factors, including erythropoietin, thrombopoietin and stem cell factor (SCF). SCF is a ligand for c-kit receptor with tyrosine kinase. We analysed the gene alteration of the c-kit extracellular domain in MPD patients by PCR-SSCP and subsequent nucleotide sequencing. The point mutation in the N-terminal part of the domain, codon 52 (Asp-->Asn), was found in two patients with primary myelofibrosis and one with chronic myelogenous leukemia. We review the literature regarding the role of SCF/c-kit system in the oncogenesis of leukemia and MPD, and then discuss the significance of our finding in the context of growth advantage of the mutated clones over the normal clones.

Adult↗
PubMed1996

Decreased L-selectin expression in CD34-positive cells from patients with chronic myelocytic leukaemia.

Abnormal adhesive interaction between bone marrow stroma and progenitors, one of the causes of unregulated proliferation in chronic myelocytic leukaemia (CML), may be caused by some alterations in adhesion molecules on CML progenitors. We investigated the expression of adhesion molecules (CD44, VLA-5, VLA-4, LFA-1, ICAM-1, L-selectin and c-kit) on bone marrow CD34++ cells from 16 CML patients by three-colour flow cytometry. The mean percentage of cells expressing L-selectin in the CD34++CD38+(or)++ fraction from untreated CML patients was significantly lower, and that in the CD34++CD38- fraction tended to be lower than that from normal controls. Among 11 CML patients treated with interferon-alpha (IFN-alpha), the mean percentage of the cells expressing L-selectin in the CD34++CD38- fraction from three patients with a low percentage of Ph1(+) cells in bone marrow was significantly higher than that from five patients with a high percentage of Ph1(+) cells. In addition, L-selectin expression rate was inversely correlated to the percentage of Ph1(+) cells. There was no significant difference between the untreated patients and normal controls with regard to the expression rates of the other adhesion molecules in each CD34++ fraction except LFA-1. These data suggest that decreased L-selectin expression in CML CD34++ cells reflects one of the features of malignant CML progenitors.

ADP-ribosyl Cyclase↗
PubMed1996

No alteration in DNA topoisomerase I gene related to CPT-11 resistance in human lung cancer.

Mutations and reduced expression of DNA topoisomerase I (topo I) gene have been shown to be important in the acquisition of resistance to camptothecin and its analogues in vitro, but their significance has not been verified in vivo. We investigated possible topo I gene mutations and topo I mRNA expression levels in 127 samples obtained from 56 patients with lung tumors, including patients who had developed clinical resistance to topo I inhibitors. No mutations were detected in any of the samples examined and expression levels did not differ significantly between clinically resistant cases and others. However, the topo I mRNA expression level was significantly higher in small cell lung carcinomas than in non-small cell lung carcinomas (P < 0.05). These results suggest that topo I mRNA levels may affect CPT-11 sensitivity in human lung cancer. However, topo I gene mutations and reduced topo I mRNA expression may not be the main mechanism of clinically acquired resistance to camptothecin analogues in vivo.

Adult↗
PubMed1995

Expression of the vascular endothelial growth factor (VEGF) receptor gene, KDR, in hematopoietic cells and inhibitory effect of VEGF on apoptotic cell death caused by ionizing radiation.

Vascular endothelial growth factor (VEGF) has been identified as a peptide growth factor specific for vascular endothelial cells. In this study, we demonstrated the expression of the KDR gene transcript, which encodes a cell surface receptor for VEGF, in normal human hematopoietic stem cells, megakaryocytes, and platelets as well as in human leukemia cell lines, HEL and CMK86. Moreover, we showed the expression of VEGF gene transcript in these normal fresh cells and cell lines. To elucidate biological functions of VEGF on hematopoiesis, we determined whether this growth factor has mitogenic activity to hematopoietic cells or the ability to suppress apoptotic cell death. The liquid culture and colony-formation assay revealed that VEGF suppressed apoptotic cell death of both CMK86 cells and normal hematopoietic stem cells caused by gamma-ray irradiation, although mitogenic activity of VEGF was not detected. The ability of VEGF to suppress apoptotic cell death was independent of the change of cell cycle distribution. These data suggest that VEGF may play an important role in survival or maintenance of hematopoietic stem cells due to the prevention of apoptotic cell death caused by some stresses such as ionizing radiation and that VEGF may give leukemia cells some abilities of resistance against radiotherapy in an autocrine or paracrine manner.

Apoptosis↗
PubMed1995

Interaction of interleukin 7 (IL-7) with glycosaminoglycans and its biological relevance.

We have investigated the binding of interleukin 7 (IL-7) to sulfated glycosaminoglycans and evaluated its biological consequences. IL-7 binds to heparin and heparan sulfate, to a lesser extent to dermatan sulfate and does not bind to chondroitin sulfate. It was eluted from heparin by 0.3-0.6 M NaCl and from heparan sulfate by < 0.3 M NaCl. We also measured the affinity of IL-7 for heparin using an affinity co-electrophoresis method and found an affinity of 25 nM. In spite of these findings, IL-7 does not bind to the S17 cell line which supports lymphopoiesis. However, addition of heparin to cultures of an IL-7-dependent pre-B cell line (2E8) inhibited IL-7-stimulated proliferation and IL-7 complexed with heparin was more resistant than free IL-7 to protease treatment. Taken together, these results suggest that heparin may act as a carrier for IL-7, blocking its interaction with target cells and protecting it from degradation during transit.

Animals↗
PubMed1995

Coronary angioplasty of chronic total occlusions with bridging collateral vessels: immediate and follow-up outcome from a large single-center experience.

OBJECTIVES: The purpose of the present study was to assess the effect of bridging collateral vessels on the success of coronary angioplasty of chronic total occlusions in the context of state of the art technology and operator skill. BACKGROUND: Coronary angioplasty of chronic total occlusions has been associated with relatively low success rates. Because the presence of bridging collateral vessels in chronic total occlusion has been reported to be the major predictive factor in procedural failure, angioplasty is often not recommended in patients with such vessels. METHODS: Three hundred ninety-seven consecutive patients undergoing coronary angioplasty for chronic total occlusion were classified into two groups. Patients in group I had chronic total occlusion with bridging collateral vessels (97 patients, 109 total occlusions), and patients in group II had chronic total occlusion without such vessels (300 patients, 324 total occlusions). RESULTS: The mean +/- SD duration of occlusion was 46 +/- 66 months (range 2 to 170) in group I and 27 +/- 39 months (range 2 to 112) in group II (p < 0.05, high power value 0.83, group I vs. group II). Angioplasty for single-vessel disease was performed in a smaller proportion of patients in group I than in group II (22% vs. 36%, p < 0.05; power value 0.77). Procedural success was achieved in 82 chronic total occlusions in group I and 270 chronic total occlusions in group II (75% vs. 83%, p = 0.07; power value 0.53). The rates of restenosis and reocclusion were 54% and 16%, respectively, for group I and 56% and 13%, respectively, for group II (p = 0.76, 0.46; power value 0.51, 0.47). Complications were minor with no Q wave infarction or requirement for urgent bypass surgery in either group. Of 81 patients with unsuccessful coronary angioplasty, 1 patient from group I (1%) and 3 patients from group II (1%) required pericardiocentesis because of cardiac tamponade. Guide wire manipulation did not impair the flow of bridging collateral channels in group I. CONCLUSIONS: Coronary angioplasty can open chronic total occlusions, with or without bridging collateral channels, for safe and effective recanalization without major complications.

Aged↗
PubMed1995

Expression of c-Mpl and c-Mpl ligand gene in hematopoietic cells of individuals with and without myeloproliferative disorders and leukemia cell lines.

We examined the expression of c-Mpl (MPL) and c-Mpl ligand (ML) gene in hematopoietic cells in individuals with and without myeloproliferative disorders (MPD) and leukemic cell lines by RT-PCR. The MPL gene transcripts were detected in normal CD34+ cells, platelets, megakaryocytes and monocytes, while the ML gene was expressed in CD34+ cells, megakaryocytes, T cells, monocytes and bone marrow fibroblasts, as well as liver tissue. The ML gene product produced in the bone marrow microenvironment might, in part, be involved in hematopoiesis. The MPL gene expression was detected in platelets and peripheral blood mononuclear cells from the majority of patients with MPD including chronic myelocytic leukemia (CML), polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). In contrast, the ML gene expression was found in the majority of ET and CML patients, but not in PV or PMF patients. These findings suggest that even in MPD the megakaryocytopoiesis depends on the MPL signal transduction system, and that in ET and CML, the ML production by mononuclear cells in the bone marrow microenvironment might play a part in the higher megakaryocytopoiesis observed in these diseases. Both the MPL and ML gene expression were detected in all the leukemic cell lines tested, suggesting that this cytokine/receptor system is involved in cell growth through autocrine and paracrine systems.

Base Sequence↗
PubMed1995

Determination of various cytokines and type III procollagen aminopeptide levels in bronchoalveolar lavage fluid of the patients with pulmonary fibrosis: inverse correlation between type III procollagen aminopeptide and interferon-gamma in progressive patients.

We measured levels of cytokines and type III procollagen aminopeptides (procollagen III peptides) in bronchoalveolar lavage fluid obtained from 20 patients with stable pulmonary fibrosis (PF) and seven patients with progressive PF, and nine control subjects to determine the role of cytokines in the development of PF. Procollagen III peptide levels were markedly increased in progressive PF patients. Tumour necrosis factor-alpha, interleukin-6, transforming growth factor-beta and interferon-gamma (IFN-gamma) levels were elevated in both PF patients as compared with controls, with a tendency of higher levels in progressive patients, whereas interleukin-1 beta (IL-1 beta) level was decreased in both PF patients. When the correlation between procollagen III peptide and various cytokine levels was analysed the only significant correlation was inversely between procollagen III peptide and IFN-gamma in progressive PF patients. These results indicated that although multiple cytokines may be involved in the development of PF, the negative role of IFN-gamma in active collagen synthesis could be also important.

Adult↗
PubMed1995

c-kit point mutation of extracellular domain in patients with myeloproliferative disorders.

c-kit is a tyrosine kinase receptor whose ligand is stem cell factor (SCF). Gene alteration of the c-kit extracellular domain was analysed by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) in 25 patients with myeloproliferative disorders (MPD). In the N-terminal part of the domain, mobility shifts indicating sequence alteration were detected in three of the patients, two primary myelofibrosis (PMF) and one chronic myelogenous leukaemia (CML). The subsequent sequencing revealed the same point mutations at codon 52 causing amino acid substitution (Asp-->Asn). To our knowledge this is the first report with a c-kit point mutation found in human fresh tumour cells.

Adult↗
PubMed1995

Platelet derived growth factor expression, myelofibrosis and chronic myelogenous leukemia.

CML is often associated with myelofibrosis, and fibrosis in the accelerated phase is one of the diagnostic criteria for this accelerated phase. In this review, the mechanism of myelofibrosis associated with CML is discussed with emphasis on the cell origin of the production and release of platelet derived growth factor (PDGF) and its interaction with marrow fibroblasts. In the initial stage of myelofibrosis in chronic phase CML, atypical small megakaryocytes might leak PDGF, possibly PDGF-AB, together with other growth factors. As the clinical phase of the disease progresses to accelerated or blastic phase, a larger quantity of PDGF-AB or PDGF-BB might be secreted from blastic cells with myeloid phenotype. In addition some fibroblasts may be attracted by the PDGF and proliferate, and deposit collagen as well as fibronectin in the bone marrow stroma.

Blast Crisis↗
PubMed1995

[Neoadjuvant chemotherapy of liver tumors metastasized by sigmoid colon cancer: a case report of CDDP/5-FU intraarterial infusion therapy followed by hepatectomy].

A case of liver tumors metastasized by Sigmoid colon cancer was treated with intrahepatic arterial infusion of CDDP (10 mg) and 5-FU (250 mg) via subcutaneously implanted reservoir. After 20 administrations of CDDP and 5-FU, the tumors in the right lobe of the liver disappeared, but those in the left lobe remained. Therefore left hepatectomy was carried out. Six months after the hepatectomy, a nodule recurrence was disclosed in the right lobe of the liver. With re-elevated serum CEA level, subsequent intrahepatic arterial infusion of CDDP and 5-FU the nodule size reduced with normalization of the serum CEA level.

Aged↗
PubMed1994

Expression of fibroblast growth factor gene family and its receptor gene family in the human upper gastrointestinal tract.

All of 13 human esophageal cancer cell lines contained mRNAs for both basic fibroblast growth factor (bFGF) and its receptor, FGFR1/N-sam protein, while they did not have mRNAs for keratinocyte growth factor (KGF) despite the presence of mRNAs for the KGF receptor gene, K-sam. The results indicate that in human esophageal cancer, bFGF plays roles in an autocrine manner, while KGF acts as a paracrine mediator. In contrast, only one of seven human gastric cancer cell lines contained bFGF mRNAs, while three out of the seven had mRNAs for FGFR1/N-sam protein. The KGF gene was not expressed in any of the gastric cancer cell lines, while K-sam mRNAs were detected in six out of the seven. The results demonstrate that in most human gastric cancers, bFGF does not act as an autocrine mediator, while KGF acts as a paracrine factor. The mRNAs for the other four members of the fibroblast growth factor (FGF) family, including acidic FGF, int-2 protein, hst-1 protein, FGF5 protein and FGF6/hst-2 protein could not be detected in the esophageal and gastric cancer cell lines.

Adenocarcinoma↗
PubMed1994

A comparison study of IFN-gamma, ADA, and CA125 as the diagnostic parameters in tuberculous pleuritis.

Adenosine deaminase in pleural fluid (pADA), CA125 in serum (sCA125), and IFN-gamma in pleural fluid (pIFN-gamma) were measured in patients with pleurisy of various causes to evaluate their diagnostic utility in tuberculous pleuritis (TBP). We studied 39 pleural fluid samples, including 11 TBP and 28 non-TBP. With both pADA and sCA125, although the median values were much higher in TBP than in non-TBP groups, there was considerable overlap between the two groups. The sensitivity, specificity, and diagnostic efficiency were 81.8%, 89.3%, and 87.2%, respectively, when pADA values of more than 45 U ml-1 were considered, and they were 100%, 75.0%, and 84.2%, respectively, when sCA125 values of more than 35 U ml-1 were considered. In contrast, pIFN-gamma values were significantly higher in TBP patients (5.8 +/- 3.0 IU ml-1; mean +/- S.D.) than those in non-TBP patients (< 0.3 IU ml-1), leading to both a sensitivity and a specificity of 100%.

Adenosine Deaminase↗
PubMed1994

[A case of gauzeoma with recurrent massive hemoptysis mimicking aspergilloma].

A 52-year-old woman who had received a right upper lobectomy and thoracoplasty for the treatment of pulmonary tuberculosis 30 years prior to the present disorder, was admitted to out hospital with massive hemoptysis. We diagnosed aspergilloma clinically because chest X-ray showed a fungus ball-like mass with meniscus sign. Right middle and lower lobectomies were performed after the 7th bronchial arterial embolization for recurrent hemoptysis. The resected specimen showed a mass of old gauze, a so-called "gauzeoma". We have found no previous reports of gauzeoma with both meniscus sign and recurrent massive hemoptysis mimicking aspergilloma.

Aspergillosis↗