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Junji Tanaka

Publications and source records attributed to Junji Tanaka.

At least 55 records · Page 3Linked to original sources
PubMed2004

Path integral hybrid Monte Carlo algorithm for correlated Bose fluids.

Path integral hybrid Monte Carlo (PIHMC) algorithm for strongly correlated Bose fluids has been developed. This is an extended version of our previous method [S. Miura and S. Okazaki, Chem. Phys. Lett. 308, 115 (1999)] applied to a model system consisting of noninteracting bosons. Our PIHMC method for the correlated Bose fluids is constituted of two trial moves to sample path-variables describing system coordinates along imaginary time and a permutation of particle labels giving a boundary condition with respect to imaginary time. The path-variables for a given permutation are generated by a hybrid Monte Carlo method based on path integral molecular dynamics techniques. Equations of motion for the path-variables are formulated on the basis of a collective coordinate representation of the path, staging variables, to enhance the sampling efficiency. The permutation sampling to satisfy Bose-Einstein statistics is performed using the multilevel Metropolis method developed by Ceperley and Pollock [Phys. Rev. Lett. 56, 351 (1986)]. Our PIHMC method has successfully been applied to liquid helium-4 at a state point where the system is in a superfluid phase. Parameters determining the sampling efficiency are optimized in such a way that correlation among successive PIHMC steps is minimized.

Journal Article↗
PubMed2004

Hepatitis B virus reactivation in a case of non-Hodgkin's lymphoma treated with chemotherapy and rituximab: necessity of prophylaxis for hepatitis B virus reactivation in rituximab therapy.

A patient with Non-Hodgkin's lymphoma is reported, in which reactivation of the hepatitis B virus was achieved from treatment with rituximab. The patient's HBs antigens were positive on admission, and she tested positive for HBs, HBe, and HBc antibodies, and negative for the HBe antigens. She was treated with a regimen of three courses of rituximab-containing anti-cancer drugs and one course of combined anti-cancer drugs. Throughout these chemotherapy courses, prednisolone was not given. After the fourth course of chemotherapy with the third rituximab she developed hepatic dysfunction, and the serum titers of HBs and HBc antibodies suddenly decreased. After administration of lamivudine, however, she gradually recovered from liver failure.

Aged↗
PubMed2004

Allogeneic bone marrow transplantation from an unrelated donor for the treatment of chronic myelogenous leukemia in blast crisis in a patient with Kleinfelter's syndrome.

We describe the first reported Klinefelter's syndrome (KS) in which allogeneic bone marrow transplantation from an unrelated donor (UR-BMT) was performed for treatment of chronic myelogenous leukemia in blast crisis (CML-BC). A 31-year-old male patient was diagnosed as having CML-BC with KS in April 2001. The result of a bone marrow chromosomal examination were 47, XXY, t(9;22)(q34;q11). After he had been treated with chemotherapy and imatinib mesylate, he underwent UR-BMT in February 2002. After the UR-BMT, his bone marrow chromosome changed from 47, XXY, t(9;22)(q34;q11) to 46,XY and 100% donor-type chimerism was obtained. However, he relapsed on day 83 after UR-BMT. After treatment with imatinib mesylate and tapering of immunosuppressive agents, skin and liver GVHD developed and then donor-type chimerism was increased with decreased blast cells. However, the patient died due to progression of disease in October 2002.

Adult↗
PubMed2004

Molecular analysis of T-cell repertoire in patients with graft-versus-host disease after allogeneic stem cell transplantation.

Complementarity-determining region (CDR3) size spectratyping has often been used to analyze the clonal expansion of T-cells. CDR3 size spectratyping has been useful in the analysis of the oligoclonal expansion of T-cells in virus infection, graft-versus-leukemia effect (GVL), graft-versus-host disease (GVHD), and immune reconstitution of T-cells after allogeneic stem cell transplantation (allo-SCT). We analyzed 26 T cell receptor (TCR)-beta-chain subfamilies (VB) in 25 patients who underwent allo-SCT. Fifteen of these patients developed acute GVHD (aGVHD). Many TCR-VB were skewed in the early stage. In these TCR-VB subfamilies, VB6 was most often skewed at the time of skin aGVHD. We then analyzed the average score of the complexity of 26 TCR-VB spectratypings in patients with or without cGVHD. The patients who developed chronic GVHD (cGVHD) had a lower average score of TCR-VB complexity than that of patients without cGVHD (P = 0.010). In particular. the patients who developed the quiescent type and de novo type of cGVHD from 4 months after allo- SCT had a lower average score of TCR-VB complexity at 3 months than that of the patients who had no cGVHD (P = 0.0055). These results suggest that we might be able to consider a possible development of cGVHD by analyzing TCR-VB spectratyping after allo-SCT.

Adolescent↗
PubMed2004

Genetic diversity of HIV type 1 in Likasi, southeast of the Democratic Republic of Congo.

To investigate the prevalence of subtypes A and C, and the existence of recombinants of both subtypes in the southeast of the Democratic Republic of Congo (DRC), blood samples were collected from 27 HIV-infected individuals in Likasi, located in an area bordering close to Zambia, and analyzed phylogenetically. Out of the 24 strains with a positive PCR profile for pol-IN and env-C2V3, 15 (62.5%) had a discordant subtype or CRF designation: one subtype A/G (pol/env), four A/U (unclassified), three G/A, one G/CRF01, three H/A, one J/C, one CRF02 (G)/A, and one U/A. Nine (37.5%) strains had a concordant subtype or CRF designation: five subtype A, two C, one D, and one CRF02/G. The remaining three samples negative for PCR with env-C2V3 primers used in this study were further analyzed with env-gp41 primers and revealed the presence of two profiles: two J/J (pol-IN/env-gp41) and one C/G. These data highlight the presence of a high proportion (16/27, 59.3%) of recombinant strains and a low prevalence (4.1 and 7.4%) of subtype C based on env-C2V3 and pol-IN analyses, respectively, in Likasi. In addition, this is the first report that CRF02_AG exists in DRC, though the epidemiological significance of the existence of CRF02_AG in DRC remains unknown.

Democratic Republic of the Congo↗
PubMed2004

Neutrophils secrete MIP-1 beta after adhesion to laminin contained in basement membrane of blood vessels.

We have recently demonstrated that granulocyte colony-stimulating factor (G-CSF) stimulated the production of epithelial-cell-derived-neutrophil attractant-78 (ENA-78) by neutrophils and that ENA-78 might promote the accumulation of neutrophils that had migrated from the intravascular space into inflammatory tissues. In this study, we examined whether other chemokines could be secreted by neutrophils that had accumulated after migrating from the intravascular space into the inflammatory tissues. We demonstrated that adhesion to laminin contained in the basement membrane and Matrigel, which is an artificial basement membrane model, induced macrophage inflammatory protein-1 beta (MIP-1 beta) in neutrophils and that MIP-1 beta secreted by neutrophils induced the chemotaxis of dendritic cells. These findings suggest that neutrophils transmigrating through the basement membrane are stimulated to secrete MIP-1 beta by the basement membrane, inducing the transmigration of dendritic cells from the intravascular space into inflammatory tissues. We propose that neutrophils intervene between innate immune response and specific immune response by secreting MIP-1 beta during the transmigration through the basement membrane.

Basement Membrane↗
PubMed2004

Efficacy of etoposide, cyclophosphamide, and total body irradiation in allogeneic bone marrow transplantation for adult patients with hematological malignancies.

INTRODUCTION: A combination of fractionated total body irradiation (TBI) with etoposide (VP-16) and cyclophosphamide (CY) as a preconditioning regimen (VP/CY/TBI) has been reported to be safe and effective for both adults and children undergoing allogeneic bone marrow transplantation (allo-BMT). However, the reported doses of VP-16 were different. We evaluated the efficacy and safety of a VP-16 (at less than the usual dose)/CY/TBI regimen for adults with hematological malignancies who are required to receive allo-BMT. PATIENTS AND METHODS: Thirty-eight patients received VP-16, CY and TBI (VP/CY/TBI) as a preconditioning regimen for allo-BMT. Twenty-one patients were in first complete remission (1CR), six patients were in second remission (2CR) and 11 patients were in non-remission status (non-CR) before allo-BMT. These patients received allo-BMT from related donors (n=14) and unrelated donors (n=24). The preconditioning regimen consisted of VP-16 (15 mg/kg/d for 2 d), CY (60 mg/kg/d for 2 d) and 12 Gy TBI in six fractions for 3 d. RESULTS: Two patients died on day 30 after transplantation. The median follow-up period for all patients was 35.0 months (range 0.8-159.6 months). At the time of analysis, 10 patients had died. Seven of those 10 patients died because of relapse. The estimated 5-yr disease-free survival (DFS) rates for all cases and acute myelogenous leukemia and acute lymphoblastic leukemia cases were 73.6, 66.7 and 100%, respectively. The estimated 5-yr DFS rates for 1CR, 2CR and non-CR cases were 90.5, 83.3 and 40.9%, respectively (p < 0.05). CONCLUSION: Based on these findings, we suggest that a VP/CY/TBI regimen is effective and safe for adult patients with hematological malignancies in 1CR and 2CR.

Adolescent↗
PubMed2004

Effectiveness of propagermanium treatment in multiple myeloma patients.

Interferon (IFN) is one of several drugs effective in treating multiple myeloma (MM), and propagermanium is an IFN inducer. We report on 10 MM patients who were treated with propagermanium at doses from 10 to 40 mg. Two patients achieved complete remission (CR), two patients achieved partial remission (PR), and the condition of four patients was stable (stable disease, SD). After discontinuation of propagermanium, the status of MM progressed in two patients who were in SD and in two patients who had achieved PR. The administration of propagermanium was restarted in one patient resulting in a decrease in her paraprotein.

Aged↗
PubMed2004

Successful micafungin (FK463) treatment of invasive pulmonary aspergillosis in a patient with acute lymphoblastic leukemia in a phase II study.

We treated a 52-year-old woman with acute lymphoblastic leukemia (ALL) who developed invasive pulmonary aspergillosis (IPA) as a result of neutropenia following remission-induction chemotherapy. Although serological test results, such as those for platelia and pastrex, were all negative and the serum level of beta-D-glucan was low, Aspergillus DNA was detected in blood by the polymerase chain reaction method. A clinically documented diagnosis of IPA was made on the basis of chest x-rays, computed tomography scan findings, and the detection of Aspergillus DNA. Micafungin (FK463), a candin class antifungal agent, was administered at a dose of 75 to 150 mg/day, because other antifungal agents were not effective. The increase in serum concentration of micafungin was dose-dependent and was accompanied by improvement of symptoms and objective findings. Micafungin was effective for the treatment of IPA in this patient with ALL.

Antineoplastic Agents↗
PubMed2004

Aleukemic leukemia cutis in a patient with Philadelphia chromosome-positive biphenotypic leukemia.

Aleukemic leukemia cutis is a rare condition characterized by the invasion of leukemic blasts into the skin before their appearance in the peripheral blood. Leukemia cutis usually occurs in patients with myeloid leukemia, especially the myelomonocytic and monocytic types of acute myeloblastic leukemia. We describe the case of a 62-year-old woman with aleukemic leukemia cutis who developed Philadelphia-positive acute leukemia 1 month after skin involvement. Leukemic cells expressed both myeloid and B-cell lineage surface markers, and monoclonal rearrangement of the immunoglobulin heavy chain was detected by Southern blot analysis. This report is the first of a case of aleukemic leukemia cutis preceding Philadelphia-positive biphenotypic leukemia.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2004

[A case report of primary gastric adult T cell lymphoma].

A 70-year-old woman was admitted to our hospital for treatment of abdominal tumor. She had complained of left abdominal pain, body weight loss and slight fever. Upper gastrointestinal endoscopy revealed on profounding ulcerous and upheaval lesion from the upper part of gastric body to the antrum. The pathological diagnosis of the biopsy specimens was T-cell lymphoma and proviral DNA (GAG) of HTLV-I was demonstrated in the biopsy specimens. Although the patient was serologically positive for anti-human T-lymphotrophic virus type I (HTLV-I) antibody, there were no leukemia/lymphoma cells in the peripheral blood or systemic lymphadenopathy. Primary gastric Adult T-cell leukemia/lymphoma (ATLL) was diagnosed. Although she received chemotherapy, the response was poor. The prognosis of lymphoma-type ATL is known to be extremely poor. This disease is frequent in aged people. Although gastrointestinal involvement is frequent in ATLL, primary gastric ATLL is rare. We report this rare case with primary gastric ATLL and reviewing 13 cases previously reported.

Aged↗
PubMed2004

Combination of alpha-fetoprotein mRNA-based detection of hematogenously disseminating hepatocellular carcinoma cells and analysis of cancer cell membrane fluidity is more accurate in screening patients at risk of postoperative recurrence.

We developed an mRNA-based, highly specific and sensitive method to detect hepatocellular carcinoma cells present in blood. However, the reason for some patients being positive for blood analysis and negative for recurrence has yet to be found. We recently established a method to measure membrane fluidity of hepatocellular carcinoma cells, and used it to analyze the actual membrane fluidity of human hepatocellular carcinoma cells. We found that patients with carcinoma cells with lower membrane fluidity less frequently developed recurrence. The analysis of both membrane fluidity and alpha-fetoprotein mRNA thus greatly increased the accuracy of the prediction of postoperative recurrence.

Carcinoma, Hepatocellular↗
PubMed2004

[Relapse of biphenotypic leukemia confirmed by molecular study].

A 60-year-old woman was admitted to our hospital to receive treatment for relapse of biphenotypic leukemia 4 years after her initial presentation. Bone marrow examination revealed 53.5% lymphoblasts, which were classified as ALL-L2 with a normal karyotype. Lymphoblast surface markers were positive for cells of both B-cell and myeloid lineage. Immunoglobulin heavy chain and T-cell receptor gene rearrangements were investigated with PCR. Clonal rearrangement of TCR delta V delta 2-D delta 3 was detected. The same clonal rearrangement of TCR delta was found using frozen initial leukemic cells. Rather than secondary leukemia, the patient's leukemia was confirmed as relapse of the initial clone. Detection of the clonal rearrangement was also useful as a patient-specific marker for minimal residual disease.

Female↗
PubMed2004

[Current status of treatment for patients with idiopathic thrombocytopenic purpura in the Hokkaido area (evaluation of Helicobacter pylori eradication)].

Treatment guidelines for patients with idiopathic thrombocytopenic purpura (ITP) have been changed recently due to the clinical application of Helicobacter pylori (H. pylori) eradication but there has been no detailed multi-center analysis of the hematological effects of H. pylori eradication. The Clinical Hematology Forum consists of 11 large hematological departments and divisions in the Hokkaido area. We sent questionnaires to these 11 hematological departments and divisions in March 2003 to obtain information on current treatment strategies for patients with ITP and hematological results after the eradication of H. pylori. Questionnaires were returned by 9 (81.8%) of the 11 departments. Doctors in all hospitals had experience in diagnosis and treatment of H. pylori infection. Diagnostic examinations for H. pylori infection were performed in 54.3% of the registered cases. H. pylori infection was detected in 68.1% of the examined cases, and eradication treatment was performed in 87.7% of H. pylori-positive patients. H. pylori was eradicated in 52 (83.9%) of the 62 patients in whom the results of treatment could be evaluated. Among the patients whose platelet counts were less than 10.0 x 10(4)/microl, platelet recovery was observed in 48.8% of cases with successful eradication, a percentage similar to previously reported percentages in Japan. There was no prognostic factor to predict good responders before eradication treatment. Since the side effects of eradication treatment, including gastrointestinal symptoms and skin eruptions, were not serious, this method might become a front-line treatment for patients with ITP. Patient selection for eradication as an up-front treatment, analysis of the pathophysiology of platelet recovery after eradication and long-term effects should be investigated to make new treatment guidelines for newly diagnosed patients with ITP.

Adolescent↗
PubMed2004

[Prognostic efficacy for measurement of real-time quantitative PCR-based major bcr/abl mRNA in patients with Philadelphia chromosome-positive leukemia].

Evaluation of minimal residual disease (MRD) provides prognostic information on various hematological malignancies. We describe here the prognostic efficacy of real-time quantitative polymerase chain reaction (RQ-PCR)-based analysis of major bcr/abl mRNA in cases of Philadelphia chromosome-positive leukemia (Ph-leukemia). Twenty-one patients with Ph-leukemia were enrolled as subjects to determine the usefulness of RQ-PCR-based measurement of bcr-abl/abl ratios. Imatinib mesylate (imatinib) was administered to seven of the 21 patients before allogeneic stem cell transplantation (SCT). Hematological relapse or failure of treatment with SCT was observed in 2 of those patients who showed bcr-abl/abl ratios of more than 0.002%, and 5 of the 7 patients showed both RQ-PCR and RT-PCR negativity immediately after SCT. All of the 5 patients who did not receive imatinib before allogeneic SCT showed RQ-PCR negativity immediately after SCT, but the results of RT-PCR were positive in 3 patients at the same time points, and those became negative after donor lymphocyte infusion or the appearance of graft-versus-host disease. Administration of imatinib before SCT was thought to induce an early remission. On the other hand, 8 patients who received imatinib without SCT showed a remarkable decrease in bcr-abl/abl ratios. The ratio gradually rose in one patient with Ph+ALL, enabling prediction of the hematological relapse preceding detection by fluorescence in situ hybridization (FISH) analysis. Standardization of RQ-PCR analysis of bcr-abl mRNA will help to predict early hematological relapse in patients with MRD. In conclusion, it is thought that measurement of RQ-PCR-based major bcr/abl mRNA in patients who were given imatinib and were treated with SCT is useful for the evaluation of MRD and in deciding additional treatment.

Adult↗
PubMed2003

Immunoregulatory cells for transplantation tolerance and graft-versus-leukemia effect.

Various immunoregulatory cells that inhibit graft-versus-host disease (GVHD) and induce the graft-versus-leukemia (GVL) effect are found after allogeneic hematopoietic stem cell transplantation. These cells comprise CD4+CD25+ regulatory T-cells, regulatory dendritic cells (rDCs), gamma(delta) T-cells, natural killer (NK) T-cells, and NK cells and T-cells with inhibitory NK receptors. Although the first 4 types of cells effectively inhibit GVHD in animal models, with rDCs showing an inhibitory effect on GVHD in humans as well, the GVL effect was observed only in rDCs. Additional analyses are required to determine whether these cells can inhibit GVHD and exert the GVL effect in humans. In contrast, NK cells and T-cells with inhibitory NK receptors have been shown in humans to possess a suppressive activity against GVHD while preserving the GVL effect. These results indicate that immunoregulatory cells may be used to modulate GVHD and the GVL effect in clinical settings.

Animals↗