Hirokazu Murakami

Gunma University, Maebashi, Gunma Prefecture, Japan

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Publications (120)188.12 Total impact

  • Hiroshi Handa, Takayuki Saitoh, Hirokazu Murakami
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    ABSTRACT: Immunomodulatory drugs (IMiDs) including lenalidomide, a single compound shows various pharmacological action such as the stimulation of T cells and natural killer (NK) cells, the suppression hematopoietic tumor proliferation, suppression of neo-vascularisation, and anti-inflammatory action. It has been thought that IMiDs stimulates CD8+ cytotoxic T cells primarily, it is recently shown that they also stimulate CD4+ helper-T cells similarly. Lenalidomide stimulates T cells and NK-cell through production of Th1 type cytokines IL-2 and IFN-γ from CD4+ helper-T cells. Lenalidomide also activate T cells indirectly by inhibiting regulatory T cells and myeloid derived suppressor cells (MDSC) which inhibit the activation of T cells, but controversy still exist about effects on regulatory T cells.
    Nihon rinsho. Japanese journal of clinical medicine. 01/2015; 73(1):156-61.
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    ABSTRACT: Introduction: In some previous studies, vitamin B12 treatment showed immunomodulatory effects and restored the immunological abnormalities in patients with pernicious anemia (PA). In the present study, peripheral blood T cell subsets, including regulatory T cells (Tregs), were examined before and after vitamin B12 treatment in PA patients. Patients and Methods: The percentages of CD4, CD8, Th1, Th2 and Tregs were examined in 23 PA patients before vitamin B12 treatment, in 23 other PA patients after vitamin B12 treatment and in 28 healthy controls. Results: The mean percentage of CD8+ T cells was significantly higher in the control group (23.0%; 95% CI, 20.4-25.6%) than in the pre- (16.0%; 95% CI, 12.1-20.0%) and posttreatment groups (15.2%; 95% CI, 11.8-18.6%; p < 0.05). The CD4/CD8 ratio was significantly lower in the control group (2.01; 95% CI, 1.66-2.34) than in the pre- (3.45; 95% CI, 2.55-7.80) and posttreatment groups (2.97; 95% CI, 2.22-3.72; p < 0.05). There was no significant difference in the mean Th1/Th2 ratio among these groups. There were significant increases in the mean percentage of Tregs in the pre- (6.29%; 95% CI, 5.04-7.54%) and posttreatment groups (7.77%; 95% CI, 6.34-9.20%) compared with the control group (4.18%; 95% CI, 3.92-4.47%; p < 0.05). Conclusions: The percentage of Tregs was significantly higher in PA patients than in normal subjects, and this high Treg percentage was not different before and after vitamin B12 treatment. Other immunological alterations also did not recover after vitamin B12 treatment, so that these immunological changes appear to be the cause of PA and are not induced by vitamin B12 deficiency. © 2014 S. Karger AG, Basel.
    Acta Haematologica 08/2014; 133(1):83-88. · 0.89 Impact Factor
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    ABSTRACT: Various prognostic markers for multiple myeloma (MM) have been identified, and stratification using these markers is considered important to optimize treatment strategies. The international staging system (ISS) is now a widely accepted prognostic staging system for MM patients; however, its validity is controversial in the era of new therapeutic regimens, since ISS had been established before introduction of new agents. We retrospectively reviewed prognostic factors in order to seek out an alternative staging system more suitably applied to MM patients treated with novel agents. We analyzed 178 newly diagnosed MM patients who received either conventional chemotherapy without novel agents (CT; n=79) or chemotherapy with novel agents (NT; n=99). Although median overall survival (OS) of patients treated with CT is significantly different depending on stages of ISS, ISS had no effect on OS among patients treated with NT. Meanwhile, we identified hemoglobin (Hb) and plasmacytoma as independent risk factors for OS in patients who received NT. Using these two parameters, we stratified NT patients into three stages; stage 1 (Hb≥10 g/dl and absence of plasmacytoma), stage 2 (not stage 1 or 3), and stage 3 (Hb < 10 g/dl and presence of plasmacytoma). We found that there were significant differences in median OS among the three stages (8.13, 5.95, and 2.45 years for stages 1, 2, and 3, respectively). This preliminary study suggests that this alternative staging system based on Hb and plasmacytoma is a simple and useful way to predict prognosis of MM patients in the novel agent era.This article is protected by copyright. All rights reserved.
    European Journal Of Haematology 06/2014; · 2.41 Impact Factor
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    ABSTRACT: Herein, we report a patient with polycythemia vera (PV) who exhibited Philadelphia chromosome (Ph) positive CML-like clinical features after 13 years of hydroxycarbamide administration and successful treatment with a tyrosine kinase inhibitor (TKI). She was 64 years old when initially diagnosed with PV and was confirmed to be negative for BCR-ABL translocation. Thirteen years later, with increasing white blood cell and platelet counts, a BCR-ABL positive clone emerged and the JAK2V617F mutation disappeared. After TKI treatment, the BCR-ABL copy number decreased and the JAK2V617F mutation was again detected. Furthermore, MPN clinical features were observed. This case provides insights into the clonal divergence and growth advantage of the Ph positive clone over the MPN clone. Whether JAK2V617F is an MPN initiating event or a secondary mutation has been a point of discussion for the past several years. This issue is also considered in the present report.
    [Rinshō ketsueki] The Japanese journal of clinical hematology 06/2014; 55(6):687-91.
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    ABSTRACT: Novel agents such as thalidomide, lenalidomide and bortezomib have dramatically changed the treatment paradigm of multiple myeloma (MM). However, it is not clear whether these agents improve the prognosis of elderly patients who have undergone autologous stem cell transplantation (auto-SCT). We retrospectively analyzed the outcome of 318 newly diagnosed patients aged 65-70 years who were treated between January 1, 2004, and December 31, 2009. As initial therapy, 192 patients were treated with conventional chemotherapy, 88 with novel agent-containing regimens, 21 with conventional chemotherapy plus auto-SCT and the remaining 17 with novel agents plus auto-SCT. The median progression-free survival was 19.1, 24.5, 26.8 and 35.2 months, respectively, and the 5-year overall survival (OS) was 40, 62, 63 and 87%, respectively. Initial therapy with novel agents (p < 0.001) or auto-SCT (p < 0.02) significantly improved OS compared with the group without these treatment modalities. Salvage therapy with novel agents also significantly improved survival after relapse compared with conventional chemotherapy alone (p < 0.04). In a multivariate analysis, the use of novel agents was an independent prognostic factor significantly associated with extended OS (p < 0.003). These results indicate that novel agents and auto-SCT had a major impact on OS in eligible patients in this subgroup of MM. © 2014 S. Karger AG, Basel.
    Acta Haematologica 03/2014; 132(2):211-219. · 0.89 Impact Factor
  • Satoru Watanabe, Yoshiyuki Yamada, Hirokazu Murakami
    Journal of Allergy and Clinical Immunology 02/2014; 133(2):AB248. · 11.25 Impact Factor
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    ABSTRACT: A 58-year-old woman with primary intraocular lymphoma (PIOL) of her right eye was treated with combination chemotherapy (methotrexate, procarbazine and vincristine) followed by irradiation to her brain and right eye. However, the disease recurred in the right eye four months later. She was treated with intravitreal injection of methotrexate and high-dose chemotherapy in combination with autologous stem cell transplantation after salvage therapy consisting of cytarabine, etoposide and rituximab. With this treatment strategy, she has been in remission for more than one year with no deterioration of either leukoencephalopathy or cognitive function. Intravitreal injection of methotrexate and high-dose chemotherapy may now be regarded as one of the treatment choices for relapsed PIOL.
    [Rinshō ketsueki] The Japanese journal of clinical hematology 02/2014; 55(2):244-8.
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    ABSTRACT: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematological malignancy. Plasmacytoid DCs (pDCs), which are defined as lineage marker (Lin)(-)HLA-DR(+)CD56(-)CD123(+)CD11c(-) cells, are considered to be the normal counterpart of BPDCNs. However, BPDCN can be distinguished from pDCs by uniform expression of CD56. In this study, to identify a normal counterpart of BPDCN, we searched for a Lin(-)HLA-DR(+)CD56(+) population and focused on a minor subpopulation of Lin(-)DR(+)CD56(+)CD123(+)CD11c(-) cells that we designated as pDC-like cells (pDLCs). pDLC constituted 0.03% of peripheral blood mononuclear cells (PBMCs), and the pDLC/pDC ratio was higher in bone marrow cells than in PBMCs. pDLC clearly expressed BDCA2, BDCA4, and myeloid antigens, which are frequently expressed by BPDCN. pDLCs exhibited modest expression of Toll-like receptors and produced less interferon-α after CpG stimulation, but presented very low endocytic ability unlike mDCs. These functional differences were attributed to the expression profile of transcriptional factors. After in vitro culture with Flt3-ligand and GM-CSF, pDLCs expressed CD11c and BDCA1. These data suggested that pDLCs are a distinct subpopulation, with an immunophenotype similar to BPDCNs. Moreover, our results indicate that pDLCs might be immature DCs and might contribute to the immunophenotypical diversity of BPDCNs.
    PLoS ONE 11/2013; 8(11):e81722. · 3.53 Impact Factor
    This article is viewable in ResearchGate's enriched format
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    ABSTRACT: DNA methyltransferase (DNMT) 3B7 is the most expressed DNMT3B splice variant. It was reported that the loss of DNMT3B function led to overexpression of the MEthylated in Normal Thymocyes (MENT) and accelerated mouse lymphomagenesis. We investigated the DNMT3B7 expression and its relationship to MENT expression and promoter methylation in human lymphomas. DNMT3B7 and MENT expression were significantly (p<0.0001, p<0.01) higher in lymphomas than in non-malignant. Expression of DNMT3B7 and MENT were associated with MENT promoter hypomethylation. DNMT3B7 overexpression might interfere with the normal DNA methylation mechanism required for silencing the MENT proto-oncogene, and may accelerate human lymphomagenesis.
    Leukemia research 09/2013; · 2.36 Impact Factor
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    ABSTRACT: Reported is a rare case IgG4-related disease that developed 10 years after combination chemotherapy for non-Hodgkin lymphoma. A 59-year-old Japanese man with longstanding bronchial asthma was referred to our hospital for bilateral hilar lymph node enlargement. The initial diagnosis was diffuse large B cell lymphoma (DLBCL) by supraclavicular lymph node biopsy. Serum IgG was high (4550 mg/dL) at diagnosis. The patient achieved complete response following six cycles of combination chemotherapy. Ten years later, bilateral submaxillary gland swelling was observed. Serum IgG and IgG4 were 2909 and 1470 mg/dL, respectively. The patient was diagnosed with IgG4-related disease by submandibular lymph node biopsy. Due to the difficulty in distinguishing IgG4-related disease from DLBCL through imaging findings alone, pathological confirmation of such lesions by biopsy is mandatory before proceeding to treatment.
    International journal of hematology 05/2013; 98(1). · 1.17 Impact Factor
  • Hirokazu Murakami, Takayuki Saito, Hiroshi Handa
    Gan to kagaku ryoho. Cancer & chemotherapy 05/2013; 40(5):583-8.
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    ABSTRACT: A 45-year-old woman with acute myelogenous leukemia developed platelet transfusion refractoriness (PTR) after the engraftment of an allogeneic peripheral blood stem cell transplantation (PBSCT) from her multiparous sister, which was attributed to HLA antibodies that could not be detected in the patient's serum before transplantation. She achieved neutrophil engraftment by day 18 and megakaryocytopoiesis and complete donor chimerism was confirmed in the bone marrow on day 21. IgG-class HLA antibodies were detected in her serum on day 24 after PBSCT; however, on day 15, no HLA antibodies were detected. The specificity of the antibodies that emerged in the patient closely resembled that of the antibodies found in the donor. The donor had probably been immunized during pregnancy by their partner's HLA-antigens expressed by the fetus. Consequently, transplanted donor-derived cells provoked HLA antibodies in the recipient early after PBSCT, and those HLA antibodies induced PTR. The presence of HLA antibodies should be examined at least in pregnant female donors whose recipients developed PTR attributable to HLA antibodies after SCT.
    [Rinshō ketsueki] The Japanese journal of clinical hematology 02/2013; 54(2):214-8.
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    ABSTRACT: We evaluated the prognostic significance of the serum level of the soluble form of interleukin-2 receptorα (sIL-2Rα) and investigated its association with CD25 expression on tumor cells in diffuse large B-cell lymphoma (DLBCL). Three hundred and thirty-eight adult patients with newly diagnosed DLBCL were eligible for this retrospective study. 32.2% of patients were treated with CHOP-like regimen and 67.8% with R-CHOP-like regimen. CD25 expression on the surface of tumor cells was evaluated in 143 cases and its relationship with sIL-2Rα level was also investigated. Both overall survival (OS) and progression-free survival (PFS) were poorer in patients with higher sIL-2Rα, in both R-CHOP and CHOP groups. sIL-2Rα > 1,000 U/mL and performance status (PS) ≥ 2 were independently associated with poorer OS, and sIL-2Rα > 1,000 U/mL, age > 60 years, and ≥ 2 extranodal sites were independently associated with poorer PFS in the R-CHOP group. The sIL-2Rα level was higher in the CD25-positive group than in the CD25-negative group in stage 3 or 4 disease (p = 0.010). Multiple linear regression analysis showed CD25 expression to be independently correlated with sIL-2Rα levels. High sIL-2Rα is an important risk factor for survival in DLBCL treated with not only CHOP-like, but also R-CHOP-like regimens, regardless of the tumor's expression of CD25. [J Clin Exp Hematop 53(3) : 197-205, 2013].
    Journal of Clinical and Experimental Hematopathology 01/2013; 53(3):197-205.
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    ABSTRACT: The murine stem cell virus (MSCV) promoter exhibits activity in mouse hematopoietic cells and embryonic stem cells. We generated transgenic mice that expressed enhanced green fluorescent protein (GFP) under the control of the MSCV promoter. We obtained 12 transgenic founder mice through 2 independent experiments and found that the bodies of 9 of the founder neonates emitted different levels of GFP fluorescence. Flow cytometric analysis of circulating leukocytes revealed that the frequency of GFP-labeled leukocytes among white blood cells ranged from 1.6% to 47.5% across the 12 transgenic mice. The bodies of 9 founder transgenic mice showed various levels of GFP expression. GFP fluorescence was consistently observed in the cerebellum, with faint or almost no fluorescence in other brain regions. In the cerebellum, 10 founders exhibited GFP expression in Purkinje cells at frequencies of 3% to 76%. Of these, 4 mice showed Purkinje cell-specific expression, while 4 and 2 mice expressed GFP in the Bergmann glia and endothelial cells, respectively. The intensity of the GFP fluorescence in the body was relative to the proportion of GFP-positive leukocytes. Moreover, the frequency of the GFP-expressing leukocytes was significantly correlated with the frequency of GFP-expressing Purkinje cells. These results suggest that the MSCV promoter is useful for preferentially expressing a transgene in Purkinje cells. In addition, the proportion of transduced leukocytes in the peripheral circulation reflects the expression level of the transgene in Purkinje cells, which can be used as a way to monitor transgene expression properties in the cerebellum without invasive techniques.
    PLoS ONE 11/2012; 7(11):e51015. · 3.53 Impact Factor
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    ABSTRACT: Marked splenomegaly as the main presenting sign in follicular lymphoma (FL) is rare. The clinical and morphologic findings of 3 FL patients with massive splenomegaly and slight or no lymphadenopathy are presented. All cases had massive splenomegaly, and 2 had minimal peripheral lymphadenopathy with bone marrow infiltration, which is the major involved site besides the spleen. Histologically, various sizes of micronodules, composed of medium-sized centrocytes, were present in the white pulp in 2 cases in whom splenectomy was performed. The other case was complicated by nephrotic syndrome and showed aggregates of packed small lymphocytes in the spleen and renal parenchyma. Tumor cells were positive for CD10, CD20, bcl-2, and bcl-6. Since these cases are clinically similar to splenic marginal zone lymphoma, recognition of this disease and selection of the appropriate therapy are needed.
    Acta Haematologica 05/2012; 128(1):47-52. · 0.89 Impact Factor
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    ABSTRACT: To investigate the clinical significance of granulocytic sarcoma (GS) in adults with acute myeloid leukemia (AML), 434 consecutive patients with AML were analyzed retrospectively. Forty-five patients (10.4%) with GS at diagnosis were younger (P < 0.001), presented with higher white blood cell counts (P = 0.03) and were more likely to conform to French-American-British M4 (P = 0.001) and M5 (P = 0.045) classifications than those without GS. In contrast, no significant difference in frequency of cytogenetic abnormalities was found between the GS and non-GS groups. Treatment outcomes in 260 patients (40 with GS) who underwent intensive chemotherapy, excluding patients with acute promyelocytic leukemia, were investigated. Complete remission rates did not differ significantly between the GS and non-GS groups (75.0% vs 79.1%; P = 0.192, respectively) or the 5-year overall survival (OS) rates (39.9% vs 38.7%; P = 0.749, respectively). However, the GS group had a significantly higher relapse rate than the non-GS group (74.2% vs 55.3%; P = 0.048) and a significantly lower 5-year disease-free survival rate (8.2% vs 25.7%, respectively; P = 0.005). When considered together with the results of multivariate analysis, which identified the presence of GS as an independent predictor for disease-free survival time, these findings indicate that GS might identify a high-risk subset of patients with AML.
    Cancer Science 05/2012; 103(8):1513-7. · 3.53 Impact Factor
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    ABSTRACT: We analyzed the change of peripheral blood T cell subsets after moving into a house with a Healthy Air system (HAS) elimination system for various allergens, e.g. pollens, house dusts, etc. The 20 subjects were divided into an allergic group (13 subjects) and control group (7 subjects). We measured complete blood counts (CBC), white blood cell differentiation (DIFF), CD4/CD8 ratio, Th1/Th2 ratio, and percentage of CD4+CD25+T-cells and regulatory T-cells in peripheral blood, and these data were compared before and 3 and 6 months after moving into the HAS house. There was no significant difference in CBC, DIFF, CD4/CD8 ratio, and Th1/Th2 ratio before and after the move. The mean levels and 95% confidence interval of CD4+CD25+T-cells in the allergic group were as follows: before, 16.66% (12.99-20.34%); at 3 months, 13.86% (10.49-17.22%); and at 6 months, 12.66% (9.28-16.05%), respectively. Those in the control group were as follows: before, 13.60% (5.27-21.93%); at 3 months, 12.51%(5.41-19.61%); and at 6 months, 11.77% (3.93-19.61%), respectively. CD4+CD25+T-cells were significantly decreased at 6 months after the move compared to before the move in the allergic group (p < 0.01). However, there was no significant difference between before and after the move in the control group. The mean levels of regulatory T-cells were not different between before and after the move in both groups. The mean level of CD4+CD25+T-cells in subjects that had improved allergic condition was significantly decreased at 6 months after the move compared to before the move (p < 0.05). These results suggest that decreases in allergens in the home environment may affect lymphocyte subsets.
    Rinsho byori. The Japanese journal of clinical pathology 05/2012; 60(5):414-21.
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    ABSTRACT: Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by the production of autoreactive antibodies against platelet antigens. Although dysfunction of multiple aspects of cellular immunity is considered to be important in the pathogenesis of ITP, it has not been clarified which cell types play a principal role. We enrolled 46 untreated patients with chronic ITP and 47 healthy adult volunteers, and investigated by flow cytometry the percentage and absolute number of cells in their peripheral blood that participate in the regulation of cellular immunity. These included plasmacytoid dendritic cells (pDCs), myeloid dendritic cells (mDCs), natural killer (NK) cells, natural killer T (NKT) cells, regulatory T (Treg) cells, and Th17 cells. We found a significant reduction in the absolute number of pDCs, but not of mDCs, in patients with ITP when compared with healthy controls (P < 0.001). Reduced numbers of circulating pDCs were observed in both Helicobacter pylori (H. pylori)-positive and Helicobacter pylori (H. pylori)-negative patients with ITP. In contrast, there were no significant differences in the numbers of circulating Treg cells, Th17 cells, NK cells, or NKT cells. Interestingly, we observed increases in the number of pDCs after H. pylori eradication by antibiotics in responders but not in non-responders, while pDCs and mDCs decreased markedly after prednisolone therapy in both responders and non-responders. In patients without treatment, low pDC numbers persisted during the observational period. We demonstrated that the number of circulating pDCs is low in patients with primary and H. pylori-associated ITP and that it changes depending on treatment modality. Further investigation is warranted with regard to the role of pDCs in the immunopathogenesis of ITP.
    European Journal Of Haematology 04/2012; 88(4):340-9. · 2.41 Impact Factor
  • Nippon rinsho. Japanese journal of clinical medicine 04/2012; 70 Suppl 2:584-8.
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    ABSTRACT: Background. Helicobacter pylori chronically colonizes gastric/duodenal mucosa and induces gastroduodenal disease and vigorous humoral and cellular immune responses. Methods. In order to clarify the immunological changes induced by this infection, we determined the percentage and, as indicated, ratios of the following cells in peripheral blood of 45 H. pylori-infected patients and 21 control subjects: CD4+ T cell, CD8+ T cells, T helper 1 cells (Th1), T helper 2 cells (Th2), CD4+CD25+ T cells, Foxp3+ regulatory T cells (Tregs), CD4/CD8 ratio, and Th1/Th2 ratio. Results. The percentage of CD8+ T cells was significantly lower in H. pylori-infected patients (mean ± SD; 18.0 ± 7.1%) compared to control subjects (mean ± SD; 23.2 ± 7.8%) (P < 0.05). The CD4/CD8 ratio was significantly higher in H. pylori-infected patients (mean ± SD; 3.1 ± 2.4) compared to control subjects (mean ± SD; 2.1 ± 1.0) (P < 0.05). The Th1/Th2 ratio was significantly lower in H. pylori-infected patients (mean ± SD; 10.0 ± 8.5) compared to control subjects (mean ± SD; 14.5 ± 9.0) (P < 0.05). The percentage of CD4+CD25+ T cells in H. pylori-infected patients (mean ± SD; 13.2 ± 6.2%) was significantly higher than that in control subjects (mean ± SD; 9.8 ± 3.4%) (P < 0.05). However, there was no significant difference in Tregs. Conclusion. Tregs did not decrease, but the activation of humoral immunity and Th2 polarization were observed in the peripheral blood of H. pylori-infected patients. In some cases, these changes may induce systemic autoimmune diseases.
    Gastroenterology Research and Practice 03/2012; 2012:819842. · 1.62 Impact Factor
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Publication Stats

704 Citations
188.12 Total Impact Points


  • 1994–2013
    • Gunma University
      • • School of Health Science
      • • School of Medicine
      Maebashi, Gunma Prefecture, Japan
  • 2012
    • Saiseikai Maebashi Hospital
      Edo, Tōkyō, Japan
  • 2009
    • Kusatsu General Hospital
      Susatsu, Shiga, Japan
  • 2005
    • University Hospital Medical Information Network
      Edo, Tōkyō, Japan