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Dive into the research topics where Masamichi Hara is active.

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Featured researches published by Masamichi Hara.


Blood | 2010

Transplantation of allogeneic hematopoietic stem cells for adult T-cell leukemia: A nationwide retrospective study

Masakatsu Hishizawa; Junya Kanda; Atae Utsunomiya; Shuichi Taniguchi; Tetsuya Eto; Yukiyoshi Moriuchi; Ryuji Tanosaki; Fumio Kawano; Yasushi Miyazaki; Masato Masuda; Koji Nagafuji; Masamichi Hara; Minoko Takanashi; Shunro Kai; Yoshiko Atsuta; Ritsuro Suzuki; Takakazu Kawase; Keitaro Matsuo; Tokiko Nagamura-Inoue; Shunichi Kato; Hisashi Sakamaki; Yasuo Morishima; Jun Okamura; Tatsuo Ichinohe; Takashi Uchiyama

Allogeneic hematopoietic stem cell transplantation (HSCT) is increasingly used as a curative option for adult T-cell leukemia (ATL), an intractable mature T-cell neoplasm causally linked with human T-cell leukemia virus type I (HTLV-I). We compared outcomes of 386 patients with ATL who underwent allogeneic HSCT using different graft sources: 154 received human leukocyte antigen (HLA)-matched related marrow or peripheral blood; 43 received HLA-mismatched related marrow or peripheral blood; 99 received unrelated marrow; 90 received single unit unrelated cord blood. After a median follow-up of 41 months (range, 1.5-102), 3-year overall survival for entire cohort was 33% (95% confidence interval, 28%-38%). Multivariable analysis revealed 4 recipient factors significantly associated with lower survival rates: older age (> 50 years), male sex, status other than complete remission, and use of unrelated cord blood compared with use of HLA-matched related grafts. Treatment-related mortality rate was higher among patients given cord blood transplants; disease-associated mortality was higher among male recipients or those given transplants not in remission. Among patients who received related transplants, donor HTLV-I seropositivity adversely affected disease-associated mortality. In conclusion, allogeneic HSCT using currently available graft source is an effective treatment in selected patients with ATL, although greater effort is warranted to reduce treatment-related mortality.


Scandinavian Journal of Rheumatology | 2010

Mortality and cause of death in Japanese patients with rheumatoid arthritis based on a large observational cohort, IORRA

Ayako Nakajima; Eisuke Inoue; Eiichi Tanaka; Gurkirpal Singh; Eri Sato; Daisuke Hoshi; Kumi Shidara; Masamichi Hara; Shigeki Momohara; Atsuo Taniguchi; Naoyuki Kamatani; Hiroki Yamanaka

Objectives: To investigate mortality, cause of death, and risk factors related to mortality in Japanese patients with rheumatoid arthritis (RA). Methods: The IORRA cohort is a large observational cohort established in 2000 at the Institute of Rheumatology, Tokyo Womens Medical University. Essentially, all RA patients were registered and clinical parameters were assessed biannually. For patients who failed to participate in subsequent surveys, simple queries were mailed to confirm survival. Standardized mortality ratios (SMRs) were calculated and mortality risk factors were analysed using a Cox proportional hazard model. Results: We analysed 7926 patients (81.9% females; mean age 56.3 ± 13.1 years; mean disease duration 8.5 ± 8.3 years) with RA who enrolled in IORRA from October 2000 to April 2007. During the observational period (35 443.0 person-years), 289 deaths were reported. Major causes of death included malignancies (24.2%), respiratory involvement (24.2%) including pneumonia (12.1%) and interstitial lung disease (ILD) (11.1%), cerebrovascular disease (8.0%), and myocardial infarction (7.6%). As death was not confirmed in all patients, the SMR was deduced to be between 1.46 [95% confidence interval (CI) 1.32–1.60] and 1.90 (95% CI 1.75–2.07) for all patients, between 1.45 (95% CI 1.22–1.70) and 1.70 (95% CI 1.45–1.97) for men, and between 1.46 (95% CI, 1.29–1.65) and 2.02 (95% CI 1.82–2.24) for women. Factors associated with increased mortality included male gender, older age, worse physical disability, positive rheumatoid factor (RF), corticosteroid use, and presence of ILD. Conclusion: The mortality of Japanese RA patients is comparable to that in previous reports from western countries, even though the causes of death were significantly different.


British Journal of Haematology | 2009

Pregnancy-induced thrombocytopenia and TTP, and the risk of fetal death, in Upshaw-Schulman syndrome: a series of 15 pregnancies in 9 genotyped patients

Yoshihiro Fujimura; Masanori Matsumoto; Koichi Kokame; Ayami Isonishi; Kenji Soejima; Nobu Akiyama; Junji Tomiyama; Kazuhiko Natori; Yasunobu Kuranishi; Yutaka Imamura; Nobumasa Inoue; Satoshi Higasa; Masako Seike; Teruhiko Kozuka; Masamichi Hara; Hideo Wada; Mitsuru Murata; Yasuo Ikeda; Toshiyuki Miyata; James N. George

Upshaw–Schulman syndrome (USS) is a congenital thrombotic thrombocytopenic purpura (TTP) due to mutations in the gene that encodes for ADAMTS13 (ADAMTS13), but its clinical signs may be mild or absent during childhood. We have identified 37 patients with USS (24 females, 13 males) belonging to 32 families. The nine women from six families who were diagnosed during their first pregnancy are the focus of this report. Six of the nine women had episodes of thrombocytopenia during childhood misdiagnosed as idiopathic thrombocytopenic purpura. Thrombocytopenia occurred during the second–third trimesters in each of their 15 pregnancies, with 16 babies (one twin pregnancy), often followed by TTP. Of 15 pregnancies, eight babies were stillborn or died soon after birth, and the remaining seven were all premature except one, who was born naturally following plasma infusions to the mother that had started at 8 weeks’ gestation. All nine USS women had severely deficient ADAMTS13 activity. ADAMTS13 analyses demonstrated that eight women were compound heterozygotes of Y304C/G525D (2 siblings), R125VfsX6/Q1302X (2 siblings), R193W/R349C (2 siblings), I178T/Q929X, and R193W/A606P; one woman was homozygous for R193W. Only the R193W mutation has been previously reported. These observations emphasize the importance of measuring ADAMTS13 activity in the evaluation of thrombocytopenia during childhood and pregnancy.


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, P < 0.01; 10/21 v 1/15 at 4 weeks, P < 0.01). 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 (P < 0.01). These results suggest an advantage for allo‐PBSCT over allo‐BMT in terms of suppression of HHV‐6 reactivation and prevention of subsequent complications.


Blood | 2012

Impact of graft-versus-host disease on outcomes after allogeneic hematopoietic cell transplantation for adult T-cell leukemia: a retrospective cohort study

Junya Kanda; Masakatsu Hishizawa; Atae Utsunomiya; Shuichi Taniguchi; Tetsuya Eto; Yukiyoshi Moriuchi; Ryuji Tanosaki; Fumio Kawano; Yasushi Miyazaki; Masato Masuda; Koji Nagafuji; Masamichi Hara; Minoko Takanashi; Shunro Kai; Yoshiko Atsuta; Ritsuro Suzuki; Takakazu Kawase; Keitaro Matsuo; Tokiko Nagamura-Inoue; Shunichi Kato; Hisashi Sakamaki; Yasuo Morishima; Jun Okamura; Tatsuo Ichinohe; Takashi Uchiyama

Allogeneic hematopoietic cell transplantation (HCT) is an effective treatment for adult T-cell leukemia (ATL), raising the question about the role of graft-versus-leukemia effect against ATL. In this study, we retrospectively analyzed the effects of acute and chronic graft-versus-host disease (GVHD) on overall survival, disease-associated mortality, and treatment-related mortality among 294 ATL patients who received allogeneic HCT and survived at least 30 days posttransplant with sustained engraftment. Multivariate analyses treating the occurrence of GVHD as a time-varying covariate demonstrated that the development of grade 1-2 acute GVHD was significantly associated with higher overall survival (hazard ratio [HR] for death, 0.65; P = .018) compared with the absence of acute GVHD. Occurrence of either grade 1-2 or grade 3-4 acute GVHD was associated with lower disease-associated mortality compared with the absence of acute GVHD, whereas grade 3-4 acute GVHD was associated with a higher risk for treatment-related mortality (HR, 3.50; P < .001). The development of extensive chronic GVHD was associated with higher treatment-related mortality (HR, 2.75; P = .006) compared with the absence of chronic GVHD. Collectively, these results indicate that the development of mild-to-moderate acute GVHD confers a lower risk of disease progression and a beneficial influence on survival of allografted patients with ATL.


Annals of the Rheumatic Diseases | 2010

Association study of TRAF1-C5 polymorphisms with susceptibility to rheumatoid arthritis and systemic lupus erythematosus in Japanese

Kazumasa Nishimoto; Yuta Kochi; Katsunori Ikari; Kazuhiko Yamamoto; Akari Suzuki; Kenichi Shimane; Yusuke Nakamura; Koichiro Yano; Noriko Iikuni; So Tsukahara; Naoyuki Kamatani; Hiroshi Okamoto; Hirotaka Kaneko; Yasushi Kawaguchi; Masamichi Hara; Yoshiaki Toyama; Takahiko Horiuchi; Kayoko Tao; Koji Yasutomo; Daisuke Hamada; Natsuo Yasui; Hiroshi Inoue; Mitsuo Itakura; Hiroki Yamanaka; Shigeki Momohara

Objective: The primary aim of this study was to investigate the association of polymorphisms of TRAF1-C5, a newly identified rheumatoid arthritis (RA) risk locus in Caucasians, with susceptibility to RA and systemic lupus erythematosus (SLE) in Japanese populations. Gene expression levels of TRAF1 and C5 to assess the functional significance of genotypes were also analysed. Methods: A multicentre association study consisting of 4 RA case-control series (4397 cases and 2857 controls) and 3 SLE case-control series (591 cases and 2199 shared controls) was conducted. Genotyping was performed using TaqMan genotyping assay for two single nucleotide polymorphisms (SNPs) that showed the best evidence of association in the previous Caucasian studies. Quantifications of TRAF1 and C5 expression were performed with TaqMan expression assay. Results: Significant differences in allele frequency for both SNPs were observed between RA and control subjects (combined odds ratio  = 1.09), while no significant difference was detected between patients with SLE and controls. Interestingly, alleles rs3761847 A and rs10818488 G had increased the risk for RA in the present study, while they decreased the risk in the original studies. A significant difference was found between risk allele carriers and non-carriers of rs10818488 for the expression level of TRAF1 in phorbol myristate acetate-stimulated lymphoblastoid cell lines (p = 0.04). Conclusion: Association of TRAF1-C5 locus with RA susceptibility was detected in the Japanese populations with modest magnitude, while no significant association was observed for SLE. Significant positive effect of genotype on the expression of TRAF1 might support the genetic association between TRAF1 and RA.


British Journal of Haematology | 2005

Impact of human leucocyte antigen mismatch on graft-versus-host disease and graft failure after reduced intensity conditioning allogeneic haematopoietic stem cell transplantation from related donors.

Takanori Teshima; Keitaro Matsuo; Kosei Matsue; Fumio Kawano; Shuichi Taniguchi; Masamichi Hara; Kazuo Hatanaka; Mitsune Tanimoto; Mine Harada; Shinji Nakao; Yasunobu Abe; Atsushi Wake; Tetsuya Eto; Yoshinobu Takemoto; Masahiro Imamura; Satoshi Takahashi; Yoji Ishida; Yoshinobu Kanda; Masaharu Kasai; Yoichi Takaue

The impact of human leucocyte antigen (HLA) incompatibility between donor and recipient on graft‐versus‐host disease (GVHD) and graft failure after reduced‐intensity conditioning stem cell transplantation (RICT) remains to be elucidated. We retrospectively analysed outcome in 341 patients who underwent RICT from related donors for haematological malignancies. The overall cumulative incidence of grade II–IV acute GVHD (aGVHD) was 40% for all subjects; 39% in recipients with HLA‐matched donors, 44% in those with one‐locus‐mismatched donors, and 50% in those with two‐ to three‐loci‐mismatched donors. In a Cox regression model adjusted for potential confounders, the tendency for grade II–IV aGVHD (P = 0·01), chronic GVHD (cGVHD) (P = 0·05) and graft failure (P = 0·033) increased with HLA disparity. Use of peripheral blood grafts instead of marrow was a risk factor for cGVHD. Use of antithymocyte globulin was associated with reduced aGVHD and cGVHD. Overall survival (OS) in recipients of two‐ to three‐loci‐mismatched RICT at 2 years (18%) was significantly worse than that in patients who received one‐locus‐mismatched RICT (51%) and HLA‐matched RICT (48%) (P < 0·0001). A two‐ to three‐loci mismatch was identified as an independent risk factor for OS (P < 0·001), but there was no significant difference in OS between HLA‐matched and one‐locus‐mismatched RICT. HLA incompatibility between the donor and recipient is an important risk factor for graft failure, aGVHD, cGVHD and OS after RICT. RICT from a one‐locus‐mismatched donor may represent an effective alternative approach in patients with high‐risk malignancies who lack HLA‐matched related donors.


British Journal of Haematology | 1999

Additional translocation (8;21)(q22;q22) in a patient with Philadelphia-positive chronic myelogenous leukaemia in the blastic phase

Kensuke Kojima; Masaki Yasukawa; Fumihiko Ishimaru; Hiromichi Dansako; Yoshinobu Matsuo; Yukio Kimura; Yuichiro Nawa; Masamichi Hara; Mine Harada

We report a case of Philadelphia‐positive chronic myelogenous leukaemia in blastic phase with the additional translocation (8;21)(q22;q22), which is frequent in acute myeloid leukaemia but not in chronic myelogenous leukaemia. The t(8;21) was not detected in the chronic phase, and was the only additional chromosomal anomaly in the blastic clone. Reverse transcription‐polymerase chain reaction revealed the AML1/ETO fusion transcript in the cells of blastic phase but not in those of chronic phase. Regarding t(9;22), the breakpoint on chromosome 22 occurred in the μ‐BCR region of the BCR gene, resulting in hybrid BCR/ABL mRNA with an e19a2 junction. Our findings provided molecular evidence that t(8;21) can occur as an additional genetic change in Philadelphia‐positive chronic myelogenous leukaemia.


International Journal of Hematology | 1998

14q11 abnormality and trisomy 8q are not common in Japanese T-cell prolymphocytic leukemia.

Kensuke Kojima; Hajime Kobayashi; Shion Imoto; Toshitaro Nakagawa; Toshimitsu Matsui; Yosunori Kawachi; Kenji Oda; Tomofumi Yano; Hikaru Kobayashi; Masaaki Noguchi; Masamichi Hara; Kazuo Oshimi

We studied ten cases of Japanese T-cell prolymphocytic leukemia (T-PLL) collected over the last 9 years. Median age was 61 years with a male predominance (M:F, 8:2). The main disease features were splenomegaly, lymphadenopathy, hepatomegaly, skin lesions and serous effusions. The clinical course was progressive with a median survival of 10 months. Immunophenotyping showed that the prolymphocytes had a post-thymic phenotype (TdT-, CD1a-, CD2+, CD3+, CD5+, CD7+) with a predominant CD4+ immunophenotype. Cytogenetic analysis showed no consistent abnormalities. 14q abnormality and trisomy 8q, which are frequently seen in T-PLL of Western countries, were found in only two and zero cases, respectively. We conclude that the clinical and biological characteristics of T-PLL in Japan are almost the same as those in Western countries. However, the cytogenetic findings of T-PLL in Japan might be different.


European Journal of Haematology | 2011

The utility of positron emission tomography/computed tomography in the staging of extranodal natural killer/T‐cell lymphoma

Hideaki Fujiwara; Yoshinobu Maeda; Yuichiro Nawa; Masayuki Yamakura; Daisuke Ennishi; Yukihiro Miyazaki; Katsuji Shinagawa; Masamichi Hara; Kosei Matsue; Mitsune Tanimoto

Natural killer (NK)/T‐cell lymphoma cases are rarely discovered using positron emission tomography/computed tomography (PET/CT). We compared the utility of PET/CT and that of conventional methods (CMs; CT with IV contrast, biopsies from primary sites, and bone marrow examinations) in the staging of extranodal NK/T‐cell lymphoma. Nineteen untreated patients with extranodal NK/T‐cell lymphoma at three institutions were analyzed. PET/CT and CMs were applied for initial workups following diagnosis. PET/CT and CMs were compared and evaluated for their ability to detect tumor lesions and their influence on the staging and treatment strategies. In total, 116 lesions were detected by CM and PET/CT. Using PET/CT, 108 lesions (93%) were discovered. The number of nodal lesions was 28: all were positive by PET/CT and 26 (93%) by CMs. The number of extranodal lesions was 89: 84 (94%) and 54 (61%) lesions were positive by PET/CT and CMs, respectively. PET/CT was superior to CMs in detecting cutaneous lesions [31/31 lesions (100%) vs. 20/31 lesions (65%), respectively; P = 0.042]. Bone marrow involvement was confirmed pathologically in only seven patients; four cases (57%) were positive by PET/CT. Using CMs, ten patients (53%) were stages I–II and nine (47%) were stages III–IV. Using PET/CT, eight patients (42%) were in stages I–II and 11 (58%) were in stages III–IV. PET/CT findings altered the stage and treatment strategy in two cases (11%). Our study demonstrated that PET/CT is a useful tool for detecting extranodal lesions in NK/T‐cell lymphoma, particularly cutaneous lesions. PET/CT may therefore influence future staging and treatment strategies.

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