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Masanao Teramura

Publications and source records attributed to Masanao Teramura.

15 recordsLinked to original sources
PubMed2007

Roles of DRB1 *1501 and DRB1 *1502 in the pathogenesis of aplastic anemia.

OBJECTIVE: Although a number of reports have documented a significantly increased incidence of HLA-DR15 in aplastic anemia (AA), the exact role of HLA-DR15 in the immune mechanisms of AA remains unclear. We herein clarify the difference between DRB1( *)1501 and DRB1( *)1502, the two DRB1 alleles that determine the presentation of HLA-DR15, in the pathophysiology of AA. MATERIALS AND METHODS: We investigated the relationships of the patients( *) HLA-DRB1 allele with both the presence of a small population of CD55(-)CD59(-) (PNH-type) blood cells and the response to antithymocyte globulin (ATG) plus cyclosporin (CsA) therapy in 140 Japanese AA patients. RESULTS: Of the 30 different DRB1 alleles, only DRB1( *)1501 (33.6% vs 12.8%, p(c) < 0.01) and DRB1( *)1502 (43.6% vs 24.4%, p(c) < 0.01) displayed significantly higher frequencies among the AA patients than among a control. AA patients possessing HLA-DR15 tended to be old, and especially, the frequency of DRB1( *)1502 in patients 40 years of age and older (52.4%) was markedly higher than that in those younger than 40 years old (16.2%, p(c) < 0.01). Only DRB1( *)1501 was significantly associated with the presence of a small population of PNH-type cells and it also showed a good response to ATG plus CsA therapy in a univariate analysis. A multivariate analysis showed only the presence of a small population of PNH-type cells to be a significant factor associated with a good response to the immunosuppressive therapy (p < 0.01). CONCLUSIONS: Although both DRB1( *)1501 and DRB1( *)1502 contribute to the development of AA, the methods of contribution differ between the two alleles.

Adolescent↗
PubMed2006

Clonally expanded T-cells in the peripheral blood of patients with idiopathic Thrombocytopenic purpura and Helicobacter pylori infection.

Eradication of Helicobacter pylori leads to platelet recovery in some patients with idiopathic thrombocytopenic purpura (ITP). Therefore, the pathogenesis of a subgroup of ITP is probably associated with H pylori infection (H pylori-related ITP). If H pylori-related ITP is a definite subgroup of ITP, specific oligoclonal T-cells might accumulate in the peripheral blood (PB). To address this issue, we performed single-strand conformation polymorphism analysis of complementarity-determining region 3 (CDR3) of the T-cell receptor beta-chain genes of PB T-cells. Fourteen ITP patients with H pylori infection and 12 ageadjusted healthy volunteers were studied. Of the 14 patients, 8 patients (responders) exhibited a platelet response after successful H pylori eradication therapy, but 6 patients (nonresponders) did not. Vbeta5.2, Vbeta15, and Vbeta19 gene usage by clonally expanded T-cells in PB obtained before H pylori eradication therapy was significantly higher in responders than in nonresponders or healthy volunteers (Vbeta5.2, P = .023; Vbeta15, P = .004; Vbeta19, P = .036). Furthermore, an abrogation of clonally expanded T-cells was observed after therapy in some responders. These findings suggest that specific T-cell clones accumulate in H pylori-related ITP and that such clones may be associated with immune-mediated destruction of platelets.

Adult↗
PubMed2005

Minor population of CD55-CD59- blood cells predicts response to immunosuppressive therapy and prognosis in patients with aplastic anemia.

We investigated the clinical significance of a minor population of paroxysmal nocturnal hemoglobinuria (PNH)-type blood cells in patients with acquired aplastic anemia (AA). We quantified CD55-CD59- granulocytes and red blood cells (RBCs) in peripheral blood from 122 patients with recently diagnosed AA and correlated numbers of PNH-type cells and responses to immunosuppressive therapy (IST). Flow cytometry detected 0.005% to 23.1% of GPI-AP- cells in 68% of patients with AA. Sixty-eight of 83 (91%) patients with an increased proportion of PNH-type cells (PNH+) responded to antithymocyte globulin (ATG) + cyclosporin (CsA) therapy, whereas 18 of 39 (48%) without such an increase (PNH-) responded. Failure-free survival rates were significantly higher (64%) among patients with PNH+ than patients with PNH- (12%) at 5 years, although overall survival rates were comparable between the groups. Numbers of PNH-type and normal-type cells increased in parallel among most patients with PNH+ who responded to IST, suggesting that these cells are equally sensitive to immune attack. These results indicate that a minor population of PNH-type cells represents a reliable marker of a positive IST response and a favorable prognosis among patients with AA. Furthermore, immune attack against hematopoietic stem cells that allows PNH clonal expansion might occur only at the onset of AA.

Adolescent↗
PubMed2005

Clonal T cells of pure red-cell aplasia.

This study detected clonal T cells in patients with acquired pure red-cell aplasia (PRCA) by Southern blotting and polymerase chain reaction (PCR). Twenty-nine adult patients with acquired PRCA were enrolled in this study. Seventeen patients had primary acquired PRCA, while 12 patients had the secondary form. Twenty-two of 29 (76%) patients demonstrated TCR rearrangement by at least one method. We divided the patients into three groups depending on T-cell clonality. The CD4/8 ratio of patients who were positive on Southern blotting was significantly lower than that of other groups. Except for the CD4/8 ratio, other laboratory findings did not significantly differ among the three groups. The CD4/8 ratio should be a useful surrogate marker to detect T-cell clonality.

Adult↗
PubMed2005

Is eradication therapy useful as the first line of treatment in Helicobacter pylori-positive idiopathic thrombocytopenic purpura? Analysis of 207 eradicated chronic ITP cases in Japan.

A retrospective study was performed to determine the prevalence of Helicobacter pylori (H pylori) infection, the effect of H pylori eradication on platelet counts, and the characteristic clinical features of chronic immune or idiopathic thrombocytopenic purpura (ITP) with H pylori infection. H pylori infection was found in 300 patients, a group that was significantly older (P < .005) and had more cases of hyperplastic megakaryocytes in the bone marrow (P = .01) than patients without H pylori infection. H pylori eradication therapy was performed in 207 H pylori-positive ITP cases, and the platelet count response was observed in 63% of the successful eradication group and in 33% of the unsuccessful eradication group (P < .005). In the successful group, the complete remission and partial remission rates were 23% and 42%, respectively, 12 months after eradication. In the majority of responders, the platelet count response occurred 1 month after eradication therapy, and the increased platelet count continued without ITP treatment for more than 12 months. H pylori eradication therapy was effective even in refractory cases, which were unresponsive to splenectomy. In conclusion, H pylori infection was involved in most ITP patients older than 40 years in Japan, and eradication therapy should be the first line of treatment in H pylori-positive ITP patients.

Adult↗
PubMed2005

Aplastic anemia.

Explore the source record for details and available documents.

Anemia, Aplastic↗
PubMed2005

Monitoring the content of reticulocyte hemoglobin (CHr) as the progression of anemia in nondialysis chronic renal failure (CRF) patients.

BACKGROUND: We previously showed that the content of reticulocyte hemoglobin (CHr) is a reliable measure of iron status in chronic dialysis patients with erythrocytopoiesis. The CHr was significantly correlated with conventional parameters of iron deficiency in dialysis patients. We attempted to utilize the measurement of CHr levels to monitor iron status and clarify the changes in iron levels that occur as renal anemia progresses in patients with chronic renal failure (CRF). METHODS: We measured CHr, iron parameters, and the intrinsic erythropoietin (EPO) concentration in nondialysis CRF patients who visited our outpatient clinic (n=211). Iron deficiency was defined according to the transferrin saturation (TSAT) and ferritin levels. Conventional red blood cell parameters and CHr levels were measured using an ADVIA120 autoanalyzer (Bayer Medical, USA). RESULTS: The mean CHr value of the nondialysis CRF patients (creatinine clearance less than 70 mL/min) was 32.3 pg, which was not significantly different from that of the dialysis patients. Significant correlations were found between CHr and ferritin levels (r=0.042, p<0.0403) and CHr and TSAT levels (r=0.040, p<0.0157). A positive correlation was observed between the CHr and serum creatinine levels. Nondialysis CRF patients treated with recombinant human EPO (rHuEPO) at a dose of 24,000 U/month exhibited lower CHr levels, compared with those of other patients who received less than 24,000 U/month. CONCLUSION: CHr is an easily measurable and trustworthy marker of iron status in nondialysis CRF patients. Moreover, the CHr level was also sensitive to iron alterations in nondialysis CRF patients receiving rHuEPO treatment, and thus, the CHr value could likely provide useful information regarding the need for iron supplementation.

Anemia, Iron-Deficiency↗
PubMed2003

Cyclosporin A therapy for patients with myelodysplastic syndrome: multicenter pilot studies in Japan.

We examined the efficacy of cyclosporin A (CsA) in 50 patients with myelodysplastic syndrome (MDS) consisting from 47 of RA, 1 of RARS, and 2 of RAEB. These patients showed various marrow cell types including hypo-, normo-, and hypercellularity. Patients belonged to the following International Prognostic Scoring System (IPSS) risk groups: 4 of low, 41 of intermediate-1, and 5 of intermediate-2. The median CsA dose was 4.58mg/kg, and treatment responses were classified according to the International Working Group (IWG) criteria. Hematological improvement (HI) was observed in 30 (60%) patients, and all of them were belonged to RA. In the patients with RARS or RAEB, no efficacy was observed. Four (8%) of the responders achieved partial remission (PR) with granulocytes > or = 1500microl(-1), Hb>11g/dl and platelets > or = 100,000microl(-1). Higher response rate (53%) was shown in erythroid lineage (HI-E) compared to platelet (HI-P, 36%) or neutrophil lineage (HI-N, 35%). When we analyzed the correlation between the response to CsA therapy and the karyotype or HLA type, there were significantly more responders with good karyotype or DRB1*1501 than with intermediate/poor karyotypes or with other HLA types. These results indicate the usefulness of CsA therapy for MDS patients with any marrow cellularity, especially for erythroid lineage and patients with good karyotype or DRB1*1501.

Adolescent↗
PubMed2003

[Emergency treatment of severe bleeding in idiopathic thrombocytopenic purpura].

In patients with severe idiopathic thrombocytopenic purpura(ITP), life-threatening hemorrhage such as intracranial or gastrointestinal hemorrhage can occur spontaneously. In this emergency situation. an attempt to increase platelet count should be done. In general, appropriate regimens include intravenous immunoglobulin and high-dose parenteral methylprednisolone either alone or in combination. These treatments should be followed by platelet transfusions, although platelets might be rapidly removed from the circulation. In this article, the strategies for emergency treatment of severe bleeding in ITP is briefly reviewed.

Emergencies↗
PubMed2002

[Severe falciparum malaria with prolonged hemolytic anemia after successful treatment with intravenous artesunate].

We report a 68-year-old woman with severe falciparum malaria contracted in Tanzania. She presented high parasitemia and was treated successfully with intravenous artesunate, a qinghaosu derivative, and aggressive supportive therapy. She developed hemolytic anemia and jaundice on day 11 and blood transfusion was required. This case illustrates that intravenous artesunate has excellent antimalarial activity with rapid efficacy and that no severe adverse effect but conventional aggressive supportive therapy is still important in the treatment of severe falciparum malaria.

Aged↗
PubMed2002

[Massive hemolysis following allogeneic peripheral blood stem cell transplantation with minor ABO incompatibility].

We observed massive hemolysis after allogeneic peripheral blood stem cell transplantation with minor ABO incompatibility (the donor was group O and the recipient group A). The patient was a 21-year-old man diagnosed as having Philadelphia chromosome-positive chronic myelogenous leukemia. On day 7 post-transplant, there was abrupt onset of massive hemolysis necessitating supportive treatment with transfusions. During the allogeneic peripheral blood stem cell transplantation the patient had received 2 x 10(8) CD3 positive cells/kg and 7.8 x 10(7) CD19 positive cells/kg donor lymphocytes with stem cells. The present case shows that in allogeneic peripheral blood stem cell transplantation with ABO incompatibility, severe hemolysis occurs early after transplantation presumably due to the transfusion of a large number of lymphocytes.

ABO Blood-Group System↗