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Nobuhiro Tsukada

Publications and source records attributed to Nobuhiro Tsukada.

18 recordsLinked to original sources
PubMed2006

Comparative single-institute analysis of cord blood transplantation from unrelated donors with bone marrow or peripheral blood stem-cell transplants from related donors in adult patients with hematologic malignancies after myeloablative conditioning regimen.

We studied the clinical outcomes of 171 adults with hematologic malignancies who received unrelated cord blood transplantation (CBT) as a primary unrelated stem-cell source (n=100), or bone marrow transplant (BMT) or peripheral blood stem-cell transplant (PBSCT) from related donors (n=71, 55 BMT and 16 PBSCT). All patients received myeloablative regimens including 12 Gy total body irradiation. We analyzed the hematologic recovery, and risks of graft-versus-host disease (GVHD), transplantation-related mortality (TRM) and relapse, and disease-free survival (DFS) using Cox proportional hazards models. Significant delays in engraftment occurred after cord blood transplantation; however, overall engraftment rates were almost the same for both grafts. The cumulative incidences of grades III to IV acute and extensive-type chronic GVHDs among CBT recipients were significantly lower than those among BMT/PBSCT recipients. Multivariate analysis demonstrated no apparent differences in TRM (9% in CBT and 13% in BMT/PBSCT recipients), relapse (17% in CBT and 26% in BMT/PBSCT recipients), and DFS (70% in CBT and 60% in BMT/PBSCT recipients) between both groups. These data suggest that unrelated cord blood could be as safe and effective a stem-cell source as related bone marrow or mobilized peripheral blood for adult patients when it is used as a primary unrelated stem-cell source.

Adolescent↗
PubMed2006

Cord blood transplantation for acute myelogenous leukemia using a conditioning regimen consisting of granulocyte colony-stimulating factor-combined high-dose cytarabine, fludarabine, and total body irradiation.

The cytotoxic effect of cytarabine (Ara-C) on myeloid leukemic cells is enhanced by concomitant use of granulocyte colony-stimulating factor (G-CSF) in vitro. The feasibility of a conditioning regimen consisting of G-CSF-combined 24 g/m2 Ara-C, 90 mg/m2 fludarabine, and 12 Gy total body irradiation was studied for five patients with acute myelogenous leukemia in cord blood transplantation (CBT). Graft vs. host disease (GVHD) prophylaxis consisted of cyclosporine and methotrexate. After the conditioning regimen, 2.48 x 10(7)/kg (2.28-3.53) of cord blood nucleated cells was infused. Neutrophil counts consistently >0.5 x 10(9)/L was achieved 24 d (22-32) after CBT. Grade I stomatitis and gastrointestinal toxicities occurred in all patients. Grades I and II acute GVHD occurred in one and four patients, respectively, which resolved without steroid therapy. Sepsis and aspergillosis occurred in two and one patients, respectively. All patients were alive without leukemia relapse at a follow up of 15 months (12-43) after CBT. This conditioning regimen could avoid the toxicities of high-dose cyclophosphamide but might enhance the cytotoxic effect of Ara-C. Large-scale studies will be needed to determine the efficacy and safety of the conditioning regimen in CBT.

Adult↗
PubMed2006

Role of erythrocytes as a reservoir for ribavirin and relationship with adverse reactions in the early phase of interferon combination therapy for chronic hepatitis C virus infections.

We investigated the relationship between serum ribavirin concentrations and clearance, as well as therapeutic efficacy and adverse reactions, in 97 Japanese patients with chronic hepatitis C virus infections treated with a 6-month course of high-dose alpha2b interferon (6 million units/day) plus ribavirin (600 to 800 mg/day) combination therapy. This randomized trial showed that the saturation of ribavirin uptake after taking ribavirin capsules does not occur within a dose range of 600 to 800 mg/day, which is a standard dosage used clinically in Japan. Serum ribavirin concentrations and clearance did not correlate with sustained virological response rates. Fourteen patients discontinued therapy because of adverse reactions, and sustained virological response rates were significantly reduced by discontinuation of therapy, while dose reduction of ribavirin did not alter the therapeutic effects. Ribavirin concentrations after 1 week and ribavirin clearance were significantly correlated with discontinuation of ribavirin; however, a multiple-regression analysis revealed that only hemoglobin concentration, but not ribavirin clearance, was a significant factor for discontinuation of therapy (odds ratio, 0.514; 95% confidence interval, 0.311 to 0.85; P = 0.0095). It appears that peripheral erythrocytes may act as a reservoir for ribavirin and regulate serum ribavirin levels in the very early phase of treatment.

Adult↗
PubMed2006

Early-onset thyrotoxicosis after unrelated cord blood transplantation for acute myelogenous leukemia.

Thyroid dysfunction is a common complication after allogeneic hematopoietic stem cell transplantation (SCT). However, thyrotoxicosis as defined by elevated serum-free thyroxine (FT4) or free triiodothyronine (FT3) levels together with low thyroid-stimulating hormone (TSH) levels is rare after SCT. Here we describe 2 patients who developed thyrotoxicosis within the first 50 days after unrelated cord blood transplantation (CBT). Patient 1 is a 32-year-old woman with acute myelogenous leukemia (AML)-M5a who underwent CBT. On day +41, she developed tachycardia. On day +48, FT4 increased to 2.2 ng/dL and TSH was suppressed to less than 0.1 microU/mL. Antithyroid peroxidase antibody was positive. On day +83, FT4 spontaneously decreased to 1.4 ng/dL. Patient 2 is a 42-year-old man with AML-M4 who underwent CBT. On day +42, he developed tachycardia. On day +48, FT3 increased to 4.75 pg/mL and TSH was suppressed to 0.02 microU/mL. Antithyroid peroxidase antibody was positive. Eight months after CBT, his thyroid function spontaneously returned to normal. The presence of antithyroid peroxidase antibody suggested that immune-mediated reactions might be associated with the development of thyrotoxicosis after CBT in our patients. The present study shows that thyrotoxicosis can occur during very early periods after CBT.

Adult↗
PubMed2006

Hemorrhagic cystitis in adults after unrelated cord blood transplantation: a single-institution experience in Japan.

Hemorrhagic cystitis (HC) is the main complication after hematopoietic stem cell transplantation (SCT). Adenovirus (AdV) is the leading cause of late-onset HC after SCT in Japan. The incidence and outcome of HC were studied in 77 adults who underwent unrelated cord blood transplantation (CBT). Thirty-two patients developed HC in a median of 19 days (range, 11-170 days) after CBT. The cumulative incidence of HC was 41.8% at 1 year. Ten patients developed gross hematuria. The cumulative incidence of moderate-to-severe HC was 13.2% at 1 year. Only 1 patient developed severe HC; AdV was detected in a urine sample from that patient. AdV was also detected in a urine sample from another patient with moderate HC after CBT. AdV in both patients was identified as AdV type 11. The cumulative incidence of AdV-induced HC was 2.8% at 1 year. The incidence of AdV-induced severe HC after CBT may be relatively low among Japanese adults. The role of other viruses, including BK virus, in the pathogenesis of HC after CBT needs to be examined.

Adenoviridae↗
PubMed2006

Varicella-zoster virus encephalitis in a patient undergoing unrelated cord blood transplantation for myelodysplastic syndrome-overt leukemia.

Varicella-zoster virus (VZV) infection of the central nervous system (CNS) is rare after hematopoietic stem cell transplantation (SCT). Here, we describe the first patient who developed VZV encephalitis after cord blood transplantation (CBT). A 35-year-old man with myelodysplastic syndrome-overt leukemia underwent CBT. On day +23, a neutrophil count consistently greater than 0.5 x 10(9)/L was achieved. On day +42, 1 mg/kg per day of prednisolone therapy was initiated for grade III acute graft-versus-host disease (GVHD). Then, the dose of prednisolone was slowly reduced. For exacerbation of chronic GVHD, the dose of prednisolone was again increased to 1 mg/kg per day on day +231. On day +265, localized cutaneous zoster in the left thoracic region occurred, but soon resolved after acyclovir therapy. On day +309, he suddenly developed diplopia. Subsequently, right facial palsy and hearing impairment occurred. No skin rash was observed. Magnetic resonance imaging (MRI) scans revealed multifocal abnormal high-signal intensity in the CNS. A high level of VZV DNA was detected in a cerebrospinal fluid specimen. He was diagnosed with VZV encephalitis. Acyclovir was given intravenously for 40 days. Four months after the onset, the neurologic symptoms had incompletely resolved. MRI scans showed substantial resolution but with mild residual lesions. The present report indicates that VZV should be considered as a possible causative agent in patients who develop multifocal neurologic symptoms of the CNS after SCT.

Acyclovir↗
PubMed2006

Posttransplantation engraftment and safety of cord blood transplantation with grafts containing relatively low cell doses in adults.

The cell dose of a graft is a critical determinant of hematopoietic recovery and survival following unrelated cord blood transplantation. Most studies have found that the minimum acceptable nucleated cell dose should be between 1.5 X 10(7) and 2.0 X 10(7) nucleated cells per kilogram of body weight to reduce the time to myeloid recovery and increase the probability of engraftment. For some patients who have indications for hematopoietic cell transplants and for whom no other graft source except cord blood is available, it is difficult to decide whether they can receive cord blood grafts containing lower cell doses. In our study, patients who received cord blood grafts containing 1.0 X 10(7) to 2.0 X 10(7) cells/kg (n = 7) exhibited slower neutrophil and platelet recoveries compared with patients who received grafts containing total nucleated cell doses of 2.0 X 10(7) cells/kg and above (n = 93); however, 4 of those low-cell-dose recipients survived with a longer follow-up. Based on these preliminary results, cord blood grafts containing less than 2.0 X 10(7) cells/kg may be useful for cases where no grafts with higher cell doses or other stem cell sources are available.

Adolescent↗
PubMed2006

Pancreatic hyperamylasemia and hyperlipasemia in association with cytomegalovirus infection following unrelated cord blood transplantation for acute myelogenous leukemia.

Cytomegalovirus (CMV)-associated pancreatitis is rare after allogeneic hematopoietic stem cell transplantation (SCT). We describe a patient who developed pancreatic hyperamylasemia and hyperlipasemia in association with CMV infection after cord blood transplantation (CBT). A 31-year-old man with acute myelogenous leukemia underwent CBT. A neutrophil count consistently greater than 500/microL was achieved on day +21. Positive results for CMV antigenemia on days +35 and +67 prompted 2 courses of preemptive therapy with ganciclovir or foscarnet. The CMV antigenemia value again became positive on day +134. On day +141, serum amylase and lipase activities markedly increased to 1221 IU/L and 894 IU/L, respectively. The patient had no abdominal symptoms. Ultrasonography and computed tomography results showed no abnormalities of the pancreas. A diagnosis of possible pancreatitis was made. After the initiation of foscarnet therapy, the CMV antigenemia results soon became negative, and serum amylase and lipase activities returned to normal. Therefore, CMV infection was considered to play a major role in the development of pancreatic hyperamylasemia and hyperlipasemia in our patient. The present report indicates that CMV infection should be included in the differential diagnosis for patients with pancreatic hyperamylasemia after SCT.

Adult↗
PubMed2006

[Clinical pathway for bleeding peptic ulcers].

We devised and evaluated a clinical pathway (CP) protocol for patients with bleeding peptic ulcers (BPU). Patients without severe comorbidities, who had been diagnosed with BPU and who had undergone endoscopic treatment, were enrolled in our study. The CP adaptation rate for BPU patients was 78.8% (89/113). The variance rate was 13.5% (12/89). The median length of admission was 10.0 +/- 4.6 days (n = 78) before and 7.4 +/- 2.9 days (n = 77) after introducing CP. Our CP for BPU was safe and resulted in shorter hospital stays and, therefore, cost reductions. In elder patients, our CP was also successful, but the variance rate was higher than in younger patients.

Adult↗
PubMed2005

Expression of BAFF-R (BR 3) in normal and neoplastic lymphoid tissues characterized with a newly developed monoclonal antibody.

BAFF-receptor (BAFF-R) is required for the successful maturation and survival of B-cells. We developed an anti-human BAFF-R monoclonal antibody (mAb), 8 A 7. The reactivity of 8 A 7 in normal and neoplastic tissue was examined by performing immunohistochemistry on paraffin-embedded sections. 8 A 7 reacted with lymphocytes in the mantle and marginal zones, but not with lymphocytes in the interfollicular area. Lymphocytes in the germinal centers were found to be negative or occasionally weakly positive for 8 A 7. BAFF-R expression was found only in B-cell lymphoma (44/80, positive cases/examined cases): B-lymphoblastic lymphoma 0/3, B-chronic lymphocytic leukemia/small lymphocytic lymphoma 4/4, mantle cell lymphoma 9/11, follicular lymphoma 10/14, diffuse large B-cell lymphoma (DLBCL) 11/25, marginal zone B-cell lymphoma 8/10, lymphoplasmacytic lymphoma 2/2, plasma cell myeloma 0/2, and Burkitt lymphoma 0/9, but not in T/NK cell lymphomas (0/19) or Hodgkin lymphoma (0/10). BAFF-R was expressed in most low-grade B-cell neoplasms and a small number of DLBCL, suggesting that BAFF-R may play an important role in the proliferation of neoplastic lymphoid cells. Thus, the mAb is very useful for further understanding of both healthy B-cell biology and its pathogenic neoplasms.

Antibodies, Monoclonal↗
PubMed2005

Nurselike cells express BAFF and APRIL, which can promote survival of chronic lymphocytic leukemia cells via a paracrine pathway distinct from that of SDF-1alpha.

We examined expression of B cell-activating factor of the tumor necrosis factor (TNF) family (BAFF) and a proliferation-inducing ligand (APRIL) on chronic lymphocytic leukemia (CLL) B cells and nurselike cells (NLCs), which differentiate from CD14+ cells when cultured with CLL B cells. NLCs expressed significantly higher levels of APRIL than monocytes and significantly higher levels of BAFF and APRIL than CLL B cells. Also, the viability of CLL B cells cultured with NLCs was significantly reduced when CLL B cells were cultured with decoy receptor of B-cell maturation antigen (BCMA), which can bind both BAFF and APRIL, but not with BAFF receptor:Fc (BAFF-R:Fc), which binds only to BAFF. The effect(s) of BAFF or APRIL on leukemia cell survival appeared additive and distinct from that of stromal cell-derived factor-1alpha (SDF-1alpha), which in contrast to BAFF or APRIL induced leukemia cell phosphorylation of p44/42 mitogen-activated protein kinase (extracellular signal-regulated kinase-1/2 [ERK1/2]) and AKT. Conversely, BAFF and APRIL, but not SDF-1alpha, induced CLL-cell activation of the nuclear factor-kappaB1 (NF-kappaB1) and enhanced CLL-cell expression of the antiapoptotic protein Mcl-1. However, BAFF, but not APRIL, also induced CLL-cell activation of NF-kappaB2. We conclude that BAFF and APRIL from NLCs can function in a paracrine manner to support leukemia cell survival via mechanisms that are distinct from those of SDF-1alpha, indicating that NLCs use multiple distinct pathways to support CLL-cell survival.

B-Cell Activation Factor Receptor↗
PubMed2005

High-dose cyclophosphamide as an effective therapy for a patient with refractory multiple myeloma relapsing after autologous stem cell transplantation.

Alkylating agents are often used to treat patients with multiple myeloma (MM). However, it is not common for high-dose cyclophosphamide (CPM) therapy to be used as a treatment for MM. Herein, we report a case of refractory MM associated with hypercalcemia. We decided to give her high-dose CPM. After this treatment, the serum calcium level decreased and the tumor mass in the iliac bone was reduced. This therapy is potentially useful for patients with refractory MM.

Antineoplastic Agents, Alkylating↗
PubMed2004

Mucosal concentration of basic fibroblast growth factor in the healing process in human giant gastric ulcers.

OBJECTIVES: Basic fibroblast growth factor (bFGF) is a key factor in the healing of human and experimental peptic ulcers, but the behavior of bFGF in human giant gastric ulcer remains to be determined. We determined the bFGF content in the rim of giant ulcers (bFGF rim) and in non-ulcerated mucosa located opposite the ulcer (bFGF opposite) before and during treatment. METHODS: Biopsy specimens were endoscopically obtained from 31 patients with giant gastric ulcers and 17 patients with small ulcers before and 2, 4 and 8 weeks after treatment. The bFGF concentrations in the specimens were measured using a sandwich enzyme immunoassay. RESULTS: Before treatment, the bFGF rim and bFGF opposite concentrations were not associated with ulcer size. The bFGF rim concentration before treatment in the rapid healing group was higher than that in the slow healing group, but no significant difference in bFGF opposite concentrations were found between the two groups. The bFGF rim concentration in the rapid healing patients decreased during treatment, while the slow healing patients showed an inverse response. The bFGF opposite concentration did not change during treatment and bFGF rim concentrations in Helicobacter pylori-positive stomachs were significantly lower than those in H. pylori-negative stomachs. CONCLUSIONS: The bFGF rim concentration is not involved in the formation of giant gastric ulcers in humans. However, the bFGF rim concentration does appear to promote healing. The bFGF opposite concentration is not related to either the formation or healing of giant gastric ulcers.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2003

Endothelin-1 suppresses plasma membrane Ca++-ATPase, concomitant with contraction of hepatic sinusoidal endothelial fenestrae.

Intracytoplasmic free calcium ions (Ca++) are maintained at a very low concentration in mammalian tissue by extruding Ca++ from the cytoplasm against a steep extracellular Ca++ concentration gradient, mainly through the activity of plasma membrane Ca++ pump-ATPase. The present study aimed to elucidate how endothelin-1 (ET-1) affects the morphology of sinusoidal endothelial fenestrae and ultrastructural distribution of plasma membrane ATPases and intracytoplasmic free Ca++ in isolated rat hepatic sinusoidal endothelial cells. Sinusoidal endothelial fenestrae were observed by scanning electron microscope. Ando's electron cytochemical method was used for ultrastructural localization of Ca++-Mg++-ATPase activity, electron immunogold postembedding method for Ca++ pump-ATPase immunoactivity, and antimonate method for intracytoplasmic free Ca++. Addition of ET-1 to sinusoidal endothelial cells significantly decreased Ca++-Mg++-ATPase activity and Ca++ pump-ATPase expression and increased intracytoplasmic free Ca++ concentration, concomitant with a decrease in diameter of sinusoidal endothelial fenestrae. Co-treatment with Bosentan abolished the actions of ET-1. These results suggest that ET-1 suppresses Ca++-Mg++-ATPase activity and Ca++ pump-ATPase expression on the plasma membrane of sinusoidal endothelial fenestrae, thereby attenuating the extrusion of intracytoplasmic free Ca++ into the extracellular space, leading to an increased concentration of intracytoplasmic free calcium ions and contraction of sinusoidal endothelial fenestrae.

Animals↗
PubMed2002

Protection of CLL B cells by a follicular dendritic cell line is dependent on induction of Mcl-1.

Chronic lymphocytic leukemia (CLL) B cells have defects in apoptosis pathways and therefore accumulate in vivo. However, when removed from the patient and cultured in vitro, these malignant cells rapidly undergo apoptosis. Recent studies suggest that leukemia cell survival is influenced by interactions with nonleukemia cells in the microenvironment of lymph nodes, marrow, and other tissues. To model such cell-cell interactions in vitro, we cultured freshly isolated CLL B cells with a follicular dendritic cell line, HK. CLL B cells cocultured with HK cells were protected from apoptosis, either spontaneous or induced by treatment with anticancer drugs. Protection against spontaneous apoptosis could also be induced by coculturing the CLL B cells with normal dendritic cells (DCs) or with a CD40-ligand (CD154)-expressing fibroblast cell line. Examination of the expression of several apoptosis-regulatory proteins revealed that coculture with HK cells or DCs induced up-regulation of the antiapoptotic Bcl-2 family protein Mcl-1 in CLL B cells, whereas CD40 ligation increased expression of Bcl-X(L). Cell-cell contact was required for HK-induced protection, and introducing neutralizing antibodies against various adhesion molecules showed that CD44 was involved in HK-mediated survival, whereas CD40, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were not. Anti-CD44 antibodies also blocked Mcl-1 induction by HK cells. Mcl-1 antisense oligonucleotides reduced leukemia cell expression of Mcl-1, and significantly suppressed HK-induced protection against apoptosis, whereas control oligonucleotides had no effect. Thus, HK cells protect CLL B cells against apoptosis, at least in part through a CD44-dependent mechanism involving up-regulation of Mcl-1, and this mechanism is distinct from that achieved by CD40 ligation. Consequently, the particular antiapoptotic proteins important for CLL survival may vary depending on the microenvironment.

Apoptosis↗
PubMed2002

Distinctive features of "nurselike" cells that differentiate in the context of chronic lymphocytic leukemia.

A subset of blood mononuclear cells from patients with chronic lymphocytic leukemia (CLL) can differentiate in vitro into "nurselike" cells (NLCs) that can protect CLL cells from apoptosis. NLCs express cytoplasmic vimentin and stromal-derived factor 1 (SDF-1). NLCs also express CD14, as well as CD11b, CD33, CD40, CD45RO, CD68, CD80, CD86, HLA-DQ, and HLA-DR, but not CD1a, CD2, CD3, CD11c, CD19, CD45RA, CD83, CD106, or CD154. Consistent with this phenotype, NLCs failed to differentiate from blood mononuclear cells that were depleted of CD14+ cells or from isolated CD19+ cells. CD14+ blood cells of healthy donors could differentiate into cells with the morphology and phenotype of NLCs when cultured in direct contact with CLL B cells, but not with normal B cells. Despite expressing antigens in common with blood monocytes, monocyte-derived dendritic cells, and macrophages, NLCs expressed significantly higher levels of CD68 than these other cell types. Consistent with the notion that NLCs are present in vivo, CD14+ splenocytes from CLL patients have NLC morphology and express significantly higher levels of CD68 than CD14+ splenocytes from persons without known B-cell malignancy. These findings indicate that although NLCs may differentiate from blood monocytes, they probably represent a distinctive hematopoietic cell type that exists in vivo, differentiates from hematopoietic CD14+ cells in the context of CLL, and in turn protect CLL cells from apoptosis via a mechanism that is independent of CD106 (vascular cell adhesion molecule-1). The interaction between CLL cells and NLCs may represent a novel target for therapy of patients with this disease.

Antigens, CD↗
PubMed2002

Acute T-lymphoblastic leukemia relapsed with the character of myeloid/natural killer cell precursor phenotype: a case report.

The leukemic lymphoblasts of a patient expressed CD7, CD13, CD33, CD34, HLA-DR and cytoplasmic CD3varepsilon. He was diagnosed with acute lymphoblastic leukemia (ALL), and successfully treated with a conventional chemotherapy for ALL. The disease relapsed three times, and the character of the cells gradually altered, i.e. CD56 expression increased and CD13, CD7 and cCD3 epsilon decreased. The phenotype of the relapsed ALL was, therefore, compatible with myeloid/natural killer cell precursor acute leukemia (M/NK-AL). Some of M/NK-AL may be closely related with T/myeloid-biphenotypic pro-T blasts, and both types of acute leukemia may develop a tendency to express myeloid antigens, and they may belong to the category of immature T lymphoid precursors.

Antigens, CD↗