Koichi Osaki
Kurume University
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Featured researches published by Koichi Osaki.
Bone Marrow Transplantation | 1997
Katsuto Takenaka; Hisashi Gondo; K Tanimoto; Koji Nagafuji; Tomoaki Fujisaki; Shin-ichi Mizuno; Toshihiro Miyamoto; Takashi Okamura; S Hayashi; Tetsuya Eto; Koichi Osaki; Kazuo Yamasaki; Tsunefumi Shibuya; Naoki Harada; Takanori Teshima; E Matsuishi; T Minematsu; Y Minamishima; Mine Harada; Yoshiyuki Niho
Cytomegalovirus (CMV) infection and CMV-associated disease were monitored using the CMV antigenemia assay in 72 patients who received allogeneic bone marrow transplantation (BMT), and their incidences were compared between related and unrelated donor transplant patients. The incidence of CMV infection after BMT was significantly higher in patients who received transplants from HLA-matched unrelated donors than from HLA-matched sibling donors (87% vs 53%, P < 0.05). cmv-associated disease developed in 73% of unrelated and in 14% of sibling donor transplant patients (P < 0.01). the peak levels of cmv antigenemia were significantly higher in unrelated donors than in sibling donor transplant patients (16 vs 1 CMV antigen-positive cells per 50 000 WBCs, P < 0.01). the median number of cmv antigen-positive cells on first detection was also significantly higher in unrelated donor transplant patients (15 vs 1, P < 0.01). the detection of cmv antigen-positive cells preceded the development of cmv-associated disease in 18% of unrelated donor transplant patients, suggesting a lower predictive value of cmv antigenemia for subsequent cmv- associated disease in unrelated donor bmt. careful monitoring and further studies are needed for the early diagnosis and prevention of cmv-associated disease in unrelated donor bmt.
International Journal of Hematology | 2008
Eijiro Oku; Taisuke Kanaji; Yuka Takata; Koichi Oshima; Ritsuko Seki; Satoshi Morishige; Rie Imamura; Korenori Ohtsubo; Michitoshi Hashiguchi; Koichi Osaki; Kazuaki Yakushiji; Kohji Yoshimoto; Hideaki Ogata; Hirofumi Hamada; Kenji Izuhara; Michio Sata; Takashi Okamura
Periostin is a secreted protein that shares structural homology with the insect axon guidance protein fasciclin 1. Periostin is expressed predominantly in collagen-rich fibrous connective tissues that are subjected to constant mechanical stresses. We have shown previously that periostin is a novel component of subepithelial fibrosis in bronchial asthma. Here, we investigated the relationship between periostin and bone marrow (BM) fibrosis. Periostin was expressed in the stroma and stromal cells of BM fibrosis specimens and to a great extent its expression levels correlated closely to the grade of fibrosis, as estimated by silver staining. However, in the present study, we found no relationship between plasma periostin levels and the extent of BM fibrosis. We also demonstrated that periostin is secreted by human BM hTERT stromal cells and that its secretion is enhanced by TGF-β, a cytokine produced by clonal proliferation of megakaryocytes and/or monocytes. These results indicate that periostin is a component of BM fibrosis and that it may play a role in the disease progression.
Acta Haematologica | 2013
Satoshi Morishige; Eijiro Oku; Yuka Takata; Yoshizo Kimura; Fumiko Arakawa; Ritsuko Seki; Rie Imamura; Koichi Osaki; Michitoshi Hashiguchi; Kazuaki Yakushiji; Shin-ichi Mizuno; Koji Yoshimoto; Koji Nagafuji; Koichi Ohshima; Takashi Okamura
The 8p11 myeloproliferative syndrome is a rare neoplasm associated with chromosomal translocations involving the fibroblast growth factor receptor 1 (FGFR1) gene located at chromosome 8p11–12. FGFR1 encodes a transmembrane receptor tyrosine kinase. The resultant fusion proteins are constitutively active tyrosine kinases that drive the proliferation of hematopoietic cells, whose uncontrolled growth can present as a myeloproliferative neoplasm. We report here the case of a 50-year-old man harboring the t(8;22)(p12;q11) chromosomal translocation in cells from both bone marrow and lymph nodes. He presented with acute leukemia and lymphoma with trilineage features. A novel mRNA in-frame fusion between exon 4 of the breakpoint cluster region (BCR) gene at chromosome 22q11 and exon 9 of FGFR1 gene on chromosome 8p11–12 was identified by reverse transcription polymerase chain reaction analysis and was confirmed by DNA sequencing. Because the patient was refractory to chemotherapy, cord blood transplantation was performed in progressive disease. It resulted in a successful outcome in which cytogenetic complete remission has been maintained for 2 years till date.
Bone Marrow Transplantation | 2000
Hisashi Gondo; C Okamura; Koichi Osaki; Kazuya Shimoda; Yoshinobu Asano; Takashi Okamura
A 38-year-old Japanese woman with severe aplastic anemia received an allogeneic bone marrow transplant from her serologically HLA-identical father. Cyclosporine and methotrexate were administered to prevent graft-versus-host disease (GVHD). However, grade III acute GVHD developed on day 44, which was successfully treated with methylprednisolone and tacrolimus. Fluconazole therapy was started for oral candidiasis on day 112, but she complained of headache soon after. In addition to glycosuria and increased serum creatinine levels, Pelger–Huët anomaly of granulocytes was found in her blood, which disappeared after discontinuation of tacrolimus. Transient occurrence of Pelger–Huët cells may be associated with tacrolimus toxicity due to drug interaction with fluconazole. Bone Marrow Transplantation (2000) 26, 1255–1257.
International Journal of Hematology | 2009
Korenori Ohtsubo; Michio Sata; Takumi Kawaguchi; Satoshi Morishige; Yuka Takata; Eijiro Oku; Rie Imamura; Ritsuko Seki; Michitoshi Hashiguchi; Koichi Osaki; Kazuaki Yakushiji; Taisuke Kanaji; Kohji Yoshimoto; Takato Ueno; Takashi Okamura
To investigate the association between hepatitis C virus (HCV) and B cell proliferation, we searched for the clonal B cells by flow cytometric analysis of the surface immunoglobulin kappa (κ):lambda (λ) light chain ratios of the circulating B (CD19+) cells in 240 HCV-positive patients and 150 negative controls with liver diseases. Clonal B cells with light chain restriction (κ:λ ratio >3:1 or <1:2) were analyzed for CD5 expression and the presence of monoclonal immunoglobulin heavy-chain (IGH) gene rearrangements and the t(14;18) chromosomal translocation. Clonal B cells were detected in 7 cases with HCV (2.9%), but was never detected in the controls (p < 0.05). Of the 7 cases, all had monoclonal IGH gene rearrangements and one had the t(14;18) chromosomal translocation. These HCV-related clonal B cells are not uniform in the intensity of CD5 expression and showed no increase in the frequencies of CD5+ population compared with non-clonal B cells. No “chronic lymphocytic leukemia-phenotype” cells were found. The loss of clonality was observed in 2 cases treated with interferon and in one case treated with splenectomy. The longitudinal study is required to determine whether these circulating clonal B cells progress to lymphoproliferative disorders in future or not.
Acta Haematologica | 2006
Korenori Ohtsubo; Eijiro Oku; Rie Imamura; Ritsuko Seki; Michitoshi Hashiguchi; Koichi Osaki; Kazuaki Yakushiji; Kohji Yoshimoto; Hideaki Ogata; Hiroaki Nagamatsu; Eiji Ando; Kazuhide Shimamatsu; Takashi Okamura; Michio Sata
We report a 66-year-old man with hepatitis C virus (HCV)-related cirrhosis and simultaneous hepatic relapse of non-Hodgkin’s lymphoma (NHL) and of hepatocellular carcinoma (HCC). Although the liver is frequently involved by NHL, hepatic colocalization of NHL and HCC is rarely detected by imaging techniques. HCV has been suggested to be lymphotrophic as well as hepatotrophic, and therefore has attracted speculation about a causative role in some cases of lymphoma. The patient had a past history of cutaneous diffuse large B cell lymphoma (DLBCL) in concurrence with HCC 32 months previously. Complete remission (CR) had been maintained for both diseases until February 2004, when ultrasonography and computed tomography (CT) showed multiple liver tumors. Two of these, appearing hyperattenuating in the arterial phase of contrast-enhanced CT, were diagnosed histopathologically as HCC, and treated with radiofrequency ablation. The other tumors, hypoattenuating in the portal phase CT, were diagnosed histopathologically as DLBCL, and treated with cyclophosphamide, tetrahydropyranyl-Adriamycin, vincristine and prednisolone (THP-COP) in combination with rituximab. CR was achieved for both DLBCL and HCC. Given the previously demonstrated immune system tropism and perturbation by HCV, the virus might have contributed to the occurrence of the NHL as well as the HCC.
Acta Haematologica | 2007
Eijiro Oku; Rie Imamura; Shuichiro Nagata; Yuka Takata; Ritsuko Seki; Korenori Otsubo; Michitoshi Hashiguchi; Koichi Osaki; Kazuaki Yakushiji; Kohji Yoshimoto; Hideaki Ogata; Michio Sata; Takashi Okamura
An untreated 66-year-old woman with chronic myelogenous leukaemia (CML) in the chronic phase was initially given imatinib mesylate, rapidly achieving a good cytogenetic response with treatment. However, acute promyelocytic leukaemia complicated by a disseminated intravascular coagulation occurred 9 months after beginning imatinib treatment. Promyelocytic crisis of CML was diagnosed by demonstration of both BCR/ABL and PML/RARα chimeric genes in leukaemic cells by karyotypic and fluorescence in situ hybridization analysis. Clonal evolution with addition of the PML/RARα translocation may have arisen in the early chronic phase of CML, with expansion of this clone during imatinib treatment. Promyelocytic crisis of CML is rare; furthermore, we know of no previous report of promyelocytic crisis occurring during treatment with imatinib.
International Journal of Hematology | 2002
Tsuyoshi Muta; Koichi Osaki; Yujirou Yamano
A 58-year-old man with a 4-month history of atypical chronic myeloid leukemia (aCML), treated with INF-α and hydroxyurea, presented with severe localized bone pain with involvement of upper limbs on July 17, 2000. Cytogenetic analysis of peripheral blood cells showed 46,XY,t(9;22)(p23;q11) and no BCR-ABL fusion gene was detected by fluorescence in situ hybridization (FISH). On October 30, 2000, x-rays revealed extended destruction of the bilateral proximal upper limbs; pain in the femoral bones appeared in December, and the patient couldn’t walk. Roentgenograms taken on January 4,2001, showed diffuse lytic changes in bilateral femoral bones. On January 23,2001, fixation of pending fractures in the bilateral femoral bones with an intramedullary rod had produced good results. The infiltration of immature myeloid cells was diagnosed by the histological findings of a bone specimen from the right femur. Because the serum levels of parathyroid hormone (PTH), PTH related protein, and calcitonin were normal, we considered that the bone destruction was caused by the invasion of immature myeloid cells. Four months later, the patient showed a marked increase in peripheral immature granulocytes. A bone marrow specimen showed blastic marrow, and he died of a brain hemorrhage. This report suggests that aCML might cause destructive bone lesions prior to the disease progression. To our knowledge, this is the first published case of aCML in which the chromosomal abnormality t(9;22)(p23;q11) was detected.Int J Hematol. 2002;76:344-348.
SpringerPlus | 2014
Kuniki Kawaguchi; Takayuki Nakamura; Masayuki Nohara; Satoko Koteda; Kei Nomura; Satoshi Morishige; Eijiro Oku; Rie Imamura; Fumihiko Mouri; Ritsuko Seki; Koichi Osaki; Michitoshi Hashiguchi; Kohji Yoshimoto; Koji Nagafuji; Takashi Okamura
A 65-year-old Japanese male with therapy-related myelodysplastic syndrome was admitted for unrelated cord blood transplantation. A cord blood unit from a male donor was obtained from the Japan Cord Blood Bank Network. The patient then received a conditioning regimen consisting of fludarabine, intravenous busulfan, and total body irradiation. Successful engraftment was obtained. The bone marrow examination on day 28 revealed trilineage engraftment, and chimerism analysis by variable number of tandem repeat polymerase chain reaction confirmed complete donor chimerism. At that time, conventional cytogenetics of the bone marrow aspirate showed 20 out of 20 metaphases with the 47, XXY karyotype characteristic of Klinefelter syndrome. Klinefelter syndrome is the most common genetic cause of human male infertility with a reported prevalence of 0.1–0.2% in the general population. In Japan Cord Blood Bank Network, there is no informed consent from parents about the possibility that post-unrelated cord blood transplantation patient evaluation may reveal donor-origin inherited diseases including cytogenetic abnormality. It is desirable to have opportunities in Japan discussing whether parents will be notified of the possibility that post-unrelated cord blood transplantation evaluation may reveal donor-derived illness incidentally.
Blood | 1998
Taisuke Kanaji; Takashi Okamura; Koichi Osaki; Mika Kuroiwa; Kazuya Shimoda; Naotaka Hamasaki; Yoshiyuki Niho