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Dive into the research topics where Katsuto Takenaka is active.

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Featured researches published by Katsuto Takenaka.


British Journal of Haematology | 1999

Monitoring of human herpesviruses after allogeneic peripheral blood stem cell transplantation and bone marrow transplantation

Yoshinobu Maeda; Takanori Teshima; Masao Yamada; Katsuji Shinagawa; Shinji Nakao; Yuju Ohno; Kensuke Kojima; Masamichi Hara; Koji Nagafuji; Shin Hayashi; Shunnichi Fukuda; Hitoshi Sawada; Kosei Matsue; Katsuto Takenaka; Fumihiko Ishimaru; Kazuma Ikeda; Kenji Niiya; Mine Harada

Herpesviruses frequently cause serious complications after allogeneic bone marrow transplantation (allo‐BMT). Recent studies have shown more rapid immune reconstitution after allogeneic peripheral blood stem cell transplantation (allo‐PBSCT) compared with allo‐BMT. However, it has not been clarified whether the improved immune reconstitution after allo‐PBSCT is associated with a lower incidence of herpesvirus infections. We monitored the emergence of Epstein‐Barr virus (EBV), cytomegalovirus (CMV), human herpesvirus 6 (HHV‐6) and HHV‐7 DNA by a nested‐double polymerase chain reaction in peripheral blood leucocytes from 22 allo‐BMT and 16 allo‐PBSCT patients. Each virus had an unique temporal profile of detection. HHV‐6 DNA was detected most frequently at 3 weeks after transplantation, whereas CMV and EBV DNA were detected later (2–3 months). Detection rates of HHV‐6 DNA at 3 and 4 weeks after allo‐BMT were significantly higher than those after allo‐PBSCT (9/16 v 2/13 at 3 weeks, Pu2003<u20030.01; 10/21 v 1/15 at 4 weeks, Pu2003<u20030.01). Detection rates of the other three herpesviruses after the two types of allogeneic transplantation were not significantly different throughout observation period. Furthermore, detection of HHV‐6 DNA within the first 4 weeks was associated with delayed platelet engraftment after both allo‐BMT and allo‐PBSCT (Pu2003<u20030.01). These results suggest an advantage for allo‐PBSCT over allo‐BMT in terms of suppression of HHV‐6 reactivation and prevention of subsequent complications.


Bone Marrow Transplantation | 2001

Hepatic graft-versus-host disease presenting as an acute hepatitis after allogeneic peripheral blood stem cell transplantation

Nobuharu Fujii; Katsuto Takenaka; Katsuji Shinagawa; Kazuma Ikeda; Yoshinobu Maeda; Kazutaka Sunami; Yasushi Hiramatsu; Keitaro Matsuo; Fumihiko Ishimaru; Kenji Niiya; Tadashi Yoshino; Noriyuki Hirabayashi; Mine Harada

Hepatic graft-versus-host disease (GVHD) generally presents as cholestatic jaundice, and increased serum alkaline phosphatase (ALP) is followed by hyperbilirubinemia and clinical jaundice. Currently accepted standards for evaluating the clinical severity of GVHD are based not on serum aminotransferase levels but on the serum bilirubin level. We describe a 17-year-old Japanese female who had increased aminotransferases without cholestasis on day 23 after allogeneic peripheral blood stem cell transplantation (allo-PBSCT). Liver biopsy revealed lymphocytic infiltration of the portal tracts and pericentral necrosis of the lobuli. The limiting plates were not clearly defined due to cellular infiltrates. There was periductal lymphocytic infiltration and vacuolization of the biliary epithelial cells with exocytosis, compatible with GVHD of cholangiohepatitic type. These findings indicate that acute hepatic GVHD may present as acute hepatitis and this should be included in the differential diagnosis for patients with increased aminotransferases after allogeneic stem cell transplantation. Bone Marrow Transplantation (2001) 27, 1007–1010.


International Journal of Hematology | 2002

Ocular Manifestation of Acute Graft-Versus-Host Disease After Allogeneic Peripheral Blood Stem Cell Transplantation

Takashi Saito; Katsuji Shinagawa; Katsuto Takenaka; Keitaro Matsuo; Tadashi Yoshino; Katsuyuki Kiura; Kenji Niiya; Mine Harada

A 26-year-old woman with acute myeloid leukemia underwent allogeneic peripheral blood stem cell transplantation from an HLA-identical brother. Eighteen days after transplantation, the patient developed grade II acute graft-versus-host disease (GVHD) and was treated with corticosteroids. On day 38, the patient complained of eye pain and lacrimation. A slitlamp examination revealed corneal ulcers and pseudomembranous formation in both eyes. Histologic and immunohistochemical examinations of the pseudomembrane disclosed an infiltrate dominated by T cells. A cytogenetic study of the pseudomembrane by fluorescence in situ hybridization identified a Y chromosome in the infiltrated mononuclear cells. Surveillance cultures from conjunctival swabs were negative.Thus, we diagnosed these ocular manifestations as an ocular involvement of acute GVHD.


Leukemia & Lymphoma | 2001

High-dose Chemotherapy with Hematopoietic Stem Cell Transplantation is Effective for Nasal and Nasal-type CD56+ Natural Killer Cell Lymphomas

Katsuto Takenaka; Katsuji Shinagawa; Yoshinobu Maeda; Masanori Makita; Teruh ko Kozuka; Atsuko Ashiba; Kazuh ko Yamamoto; Nobuharu Fujii; Yuichiro Nawa; Yasushi Hiramatsu; Kazutaka Sunami; Fumihiko Ishimaru; Tadashi Yoshimo; Katsuyuki Kiura; Mine Harada

CD56+ natural killer (NK) cell lymphomas occur frequently in the nasal and nasopharyngeal regions and carry a poor prognosis. We have studied seven cases with NK-cell lymphomas. These lymphomas showed the following immunophenotype: CD56+, CD2+, sCD3 and Epstein-Barr virus-encoded small RNAs (EBERs)+. Six patients had localized (stage I or II) disease involving the nasopharyngeal region, while one had stage III disease. One patient with stage I disease achieved a complete remission (CR) after treatment with involved-field irradiation, but subsequently relapsed and died. The remaining six patients received combination chemotherapy as primary treatment: five patients with localized stage I or II disease and one patient with advanced stage III disease. Responses to initial chemotherapy were generally poor. These six patients received a variety of salvage chemotherapy regimens, but never achieved a CR. Subsequently, four of six patients showed a highly aggressive clinical course and died of disseminated disease within 1 year from the diagnosis. Three of six patients received high-dose chemotherapy supported by syngeneic, autologous or allogeneic peripheral blood stem cell transplantation. Two of the three transplant patients achieved a CR and are now surviving in continuous CR. Our clinical experience suggests that myeloablative high-dose chemotherapy and bone marrow rescue by hematopoietic stem cell transplantation may be an effective salvage treatment modality for refractory NK-cell lymphomas and could be considered as a part of the initial therapy for these patients.


Blood Coagulation & Fibrinolysis | 2002

Life-threatening bleeding and acquired factor V deficiency associated with primary systemic amyloidosis

Emori Y; Sakugawa M; Kenji Niiya; Toru Kiguchi; Kensuke Kojima; Katsuto Takenaka; Katsuji Shinagawa; Fumihiko Ishimaru; Kazuma Ikeda; Mitsune Tanimoto; Yamasaki R; Ohara N; Mine Harada

Acquired factor X deficiency has been described in patients with amyloidosis but acquired factor V deficiency is quite rare. We report here a case of life-threatening bleeding and acquired factor V deficiency associated with primary amyloidosis. A 50-year-old man who had no previous hemorrhagic diathesis was referred to our hospital because of recurrent epistaxis, gingival bleeding and hemospermia. The laboratory examination revealed that both the prothrombin time (PT) and the activated partial thromboplastin time (aPTT) were significantly prolonged, and factor V activities were markedly decreased to 14-39% of the normal value. Other coagulation factors such as fibrinogen, prothrombin, factor VII, factor VIII, factor IX and factor X were subnormal and normal. Transaminases were slightly elevated but serological tests of hepatitis B and hepatitis C were negative. Mild hepatosplenomegaly was noted without sign of liver cirrhosis. The PT and aPTT obtained 8 years ago when he received a cholecystectomy due to cholecystitis were both normal. Specific assays for the detection of factor V inhibitor were repeatedly performed but no factor V inhibitor was found. Furthermore, a significant recovery of the infused factor V was noted shortly after an intravenous administration of 5-10 U fresh frozen plasma, but it did not last more than 6 h. Melena, bleedings into the left shoulder and buttock, and finally mortal retroperitoneal hemorrhage developed despite repeated infusions of large amounts of fresh frozen plasma. Acquired factor V deficiency associated with primary amyloidosis was suspected but histological diagnosis was not obtained because of the severe bleeding tendency. Autopsy revealed hepatosplenomegaly and massive deposits of AL amyloid in the liver, spleen, heart and other parenchymal organs. Perivascular amyloid deposition and factor V deficiency are both thought to be the cause of the severe hemorrhagic tendency seen in this patient.


Bone Marrow Transplantation | 2000

Allogeneic peripheral blood stem cell transplantation for the treatment of chronic active Epstein–Barr virus infection

Nobuharu Fujii; Katsuto Takenaka; Akio Hiraki; Yoshinobu Maeda; Kazuma Ikeda; Katsuji Shinagawa; Atsuko Ashiba; Mitsuru Munemasa; Kazutaka Sunami; Yasushi Hiramatsu; Fumihiko Ishimaru; Kenji Niiya; Tadashi Yoshino; Mine Harada

The prognosis of chronic active Epstein–Barr virus infection (CAEBV) is very poor. We describe a 24-year-old male with severe CAEBV who was treated with allogeneic peripheral blood stem cell transplantation (allo-PBSCT). On admission, EBER-1 in lymphocytes infiltrating the liver, EBV-DNA in peripheral blood mononuclear cells (PBMC) and monoclonal NK cell proliferation were confirmed. After unsuccessful chemotherapy, he received an allo-PBSCT from his HLA-identical sister. Although he died of pulmonary hemorrhage on day +19, EBV-DNA was undetectable by PCR in PBMC, and the post-mortem liver showed no EBER-1-positive lymphocytes. This experience suggests that EBV-positive lymphocytes in CAEBV may be eradicated by allo-PBSCT, thereby raising the possibility of a new treatment modality. Bone Marrow Transplantation (2000) 26, 805–808.


Bone Marrow Transplantation | 1999

Successful treatment of advanced natural killer cell lymphoma with high-dose chemotherapy and syngeneic peripheral blood stem cell transplantation

Yuichiro Nawa; Katsuto Takenaka; Katsuji Shinagawa; S Deguchi; N Matsumura; S Koyama; Yasushi Hiramatsu; Eijiro Omoto; Tadashi Yoshino; Mine Harada

CD56+ angiocentric lymphoma has currently been recognized as a distinct clinical entity which is the prototype of the putative NK cell lymphomas. A 16-year-old Japanese girl with advanced CD56+ angiocentric lymphoma received high-dose chemotherapy supported with syngeneic peripheral blood stem cell transplantation (PBSCT). Prior to syngeneic PBSCT, she received six cycles of conventional chemotherapy before transplantation, resulting in a partial response. PBSC were mobilized with granulocyte colony-stimulating factor (G-CSF) and collected from her identical twin. High-dose cyclophosphamide, MCNU, etoposide, and carboplatin were used for pretransplant conditioning. Syngeneic PBSCT was well tolerated. She achieved complete remission and is now surviving in continuous complete remission for more than 30 months after syngeneic PBSCT. Thus, marrow-ablative chemotherapy facilitated by autologous or allogeneic PBSCT should be considered as part of the primary therapy for poor prognosis NK cell lymphomas.


Transfusion | 2002

Predictive value of circulating immature cell counts in peripheral blood for timing of peripheral blood progenitor cell collection after G–CSF plus chemotherapy-induced mobilization

Teruhiko Kozuka; Kazuma Ikeda; Takanori Teshima; Kensuke Kojima; Keitaro Matsuo; Akihiro Bessho; Kazutaka Sunami; Yasushi Hiramatsu; Yoshinobu Maeda; Toshio Noguchi; Kazuhiko Yamamoto; Nobuharu Fujii; Toshi Imai; Katsuto Takenaka; Katsuji Shinagawa; Fumihiko Ishimaru; Kenji Niiya; Norio Koide; Mitsune Tanimoto; Mine Harada

BACKGROUND: Enumeration of CD34+ cells in peripheral blood (PB) before apheresis predicts the number of CD34+ cells collected, although flow cytometric techniques used are complex and expensive. In an attempt to determine the optimal timing for peripheral blood progenitor cell (PBPC) collection, the usefulness of circulating immature cell (CIC) counts in PB was evaluated.


Leukemia & Lymphoma | 2001

Lamivudine and glycyrrhizin for treatment of chemotherapy-induced hepatitis B virus (HBV) hepatitis in a chronic HBV carrier with non-Hodgkin lymphoma.

Keitaro Matsuo; Katsuto Takenaka; Hiroyuki Shimomura; Nobuharu Fujii; Katsuji Shinagawa; Katsuyuki Kiura; Mine Harada

We report a chronic hepatitis B virus (HBV) carrier with non-Hodgkin lymphoma (NHL) who developed HBV hepatitis following conventional dose chemotherapy and was successfully treated with lamivudine and glycyrrhizin. A 55 year-old male patient with primary testicular NHL (diffuse large B-cell type) relapsed. During the salvage chemotherapy, the patient showed elevated serum levels of transaminase and HBV-DNA due to HBV reactivation. Treatment with lamivudine, an antiviral nucleoside analog, was started at a dose of 100mg/day. Shortly after the treatment the HBV-DNA level was suppressed, and sustained elevation of transaminase levels were normalized after additional treatment with glycyrrhizin. This experience suggests that lamivudine combined with glycyrrhizin may be effective for controlling HBV replication and treating chemotherapy-induced HBV hepatitis in chronic HBV carriers with NHL.


International Journal of Hematology | 2002

Successful treatment of progressive NK cell lymphoma with allogeneic peripheral stem cell transplantation followed by early cyclosporine tapering and donor leukocyte infusions

Masanori Makita; Yoshinobu Maeda; Katsuto Takenaka; Katsuji Shinagawa; Kazutaka Sunami; Yasushi Hiramatsu; Nobuharu Fujii; Fumihiko Ishimaru; Kazuma Ikeda; Kenji Niiya; Tadashi Yoshino; Mine Harada

We describe a patient with progressive natural killer (NK) cell lymphoma who was treated successfully with allogeneic peripheral blood stem cell transplantation (allo-PBSCT) followed by early cyclosporine (CsA) tapering and donor leukocyte infusion (DLI). Because the disease showed early resistance to conventional chemoradiotherapy, we performed high-dose chemotherapy followed by allo-PBSCT. After achieving hematologic engraftment, the patient underwent early tapering of CsA and DLI in an attempt to induce a graft-versus-lymphoma effect. Although the disease was in a progressive state at the time of transplantation, complete remission was obtained after allo-PBSCT. As of this report, the patient has been well for more than 2 years.

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