Biomedical subjects

Hiroyuki Kuroda

Publications and source records attributed to Hiroyuki Kuroda.

15 recordsLinked to original sources

PubMed2006

Treatment effects and predictors of a 24-week course of interferon alpha-2b plus ribavirin combination therapy for patients with chronic hepatitis C.

BACKGROUND AND AIMS: In chronic hepatitis C patients with genotype 1b and a high viral load, the sustained virological response (SVR) rate remained as low as 2-3% with conventional interferon (IFN) monotherapy, but improved to more than 20% with IFN alpha-2b plus ribavirin combination therapy. This study examined the therapeutic effects and predictors of this combination therapy. METHODS: Subjects were 105 patients with chronic hepatitis C (73 males, 32 females) with a median age of 53 years (range 19-70 years). Seventy-two patients had genotype lb and 33 patients had genotype 2 (2a or 2b). Six million units (MU) or 10 MU of IFN alpha-2b was administered by intramuscular injection six times a week for the first 2 weeks, and the same amount of IFN was administered three times a week for the following 22 weeks. During the IFN administration period, 600-800 mg of oral ribavirin was administered daily. Patients who were hepatitis C virus (HCV)-RNA negative 24 weeks after the completion of administration were defined as SVR. RESULTS: The overall SVR rate was 39%; 22.2% for the genotype 1b group and 75.8% for the genotype 2 group, and the difference between the groups was significant (P < 0.0001). Multivariate logistic regression analysis indicated that the factors that contributed to SVR include genotype 2, age (younger than 53 years), and an increase in Th2 measured by flow cytometry before and 4 weeks after start of treatment. CONCLUSIONS: The overall SVR rate of IFN alpha-2b plus ribavirin combination therapy for 24 weeks was 39%, and contributing factors for SVR rate include genotype 2, age younger than 53 years and elevated Th2.

Administration, Oral↗

PubMed2006

[Effective combined modality therapy for a patient with primary adrenal lymphoma].

Primary adrenal lymphoma is a rare lymphoma with clinical features consisting of a high incidence of bilateral adrenal involvement, diffuse large B-cell histology and secondary adrenal insufficiency. We report a successful treatment of a patient with primary adrenal lymphoma using a combined modality therapy (CMT). A 62-year-old man was hospitalized with pain of the flank, and a computed tomography (CT) scan of the abdomen revealed very large, bilateral adrenal masses. A needle biopsy of the left adrenal mass revealed diffuse large B-cell lymphoma. After irradiation of both adrenal lymphomas and CHOP therapy accompanied by intrathecal treatment and rituximab, the patient underwent a left adrenalectomy and high-dose chemotherapy with autologous peripheral blood stem cell transplantation. The patient has been disease-free for 2 years after the diagnosis of primary adrenal lymphoma. In contrast to the previous reports of poor response to conventional-dose chemotherapy alone and short-term survival of patients with primary adrenal lymphoma, our patient has demonstrated that radiation therapy combined with chemotherapy and rituximab may be an effective modality as a first-line therapeutic regimen for localized primary adrenal lymphoma.

Adrenal Gland Neoplasms↗

PubMed2006

[De novo CD5-positive diffuse large B-cell lymphoma associated with autoimmune hemolytic anemia presenting as erythroid hypoplasia].

A 54-year-old woman was admitted due to high-grade fever, cervical lymphadenopathy and general malaise in May 2003. On examination, severe anemia was noted, direct Coombs and cold hemagglutinin tests were positive and the haptoglobin level was low in the peripheral blood. However, a bone marrow examination revealed marked erythroid hypoplasia. A diagnosis was made of co-existing combined type autoimmune hemolytic anemia (AIHA) and erythroid hypoplasia. A pathologic diagnosis of de novo CD5-positive diffuse large B-cell lymphoma (de novo CD5+ DLBCL) was made based on a cervical lymph node biopsy. The patient was treated with CHOP accompanied by rituximab (R-CHOP), resulting in complete remission after 3 courses of chemotherapy. The AIHA and erythroid hypoplasia subsided after 2 courses of R-CHOP. The sera obtained during erythroid hypoplasia significantly inhibited the growth of erythroid progenitor cells (erythroid colony-forming units, CFU-E) from her bone marrow collected after recovery. We report here a patient with de novo CD5+ DLBCL associated with both AIHA and erythroid hypoplasia, suggesting that the lymphoma triggered an abnormal immunity which generated some humoral inhibitors against erythropoiesis.

Anemia, Hemolytic, Autoimmune↗

PubMed2006

[Peripheral T-cell lymphoma presenting with eosinophilia due to interleukin-5 produced by lymphoma cells].

A 72-year-old male was admitted to our hospital to determine the cause of neck lymphadenopathies. He was diagnosed pathologically by a lymph node biopsy as having peripheral T-cell lymphoma (PTCL). He also had developed eosinophilia and his serum concentration of Interleukin-5 (IL-5) was extremely high. Immunostaining of a resected lymph node revealed that there were lymphoma cells which were stained with anti-IL-5 antibody. After 2 courses of CHOP therapy, the lymphadenopathies and eosinophilia disappeared and the concentration of serum IL-5 was normalized. It was suggested that IL-5 produced by lymphoma cells had induced his eosinophilia.

Aged↗

PubMed2005

[Basedow disease associated with Evans syndrome].

A 60-year-old woman was admitted to a hospital complaining of dizziness and general fatigue in October, 2004. Because of heart failure and severe anemia, she was referred to our hospital. Based on a positive direct Coombs test and an elevated level of platelet-associated IgG (PAIgG), the patient was diagnosed as having autoimmune hemolytic anemia (AIHA) associated with idiopathic thrombocytopenic purpura (ITP), i.e., Evans syndrome. Basedow disease was also diagnosed due to hyperthyroidism with an elevation of anti-thyroid stimulating hormone (TSH) receptor antibodies. Both the Evans syndrome and Basedow disease were considerably ameliorated with plasma exchange, corticosteroid and thiamazole therapy. Although Basedow disease is known to be associated with hematological disorders such as AIHA or ITP, the combination of Basedow disease and Evans syndrome is rare. We report here a case of Basedow disease associated with Evans syndrome.

Anemia, Hemolytic, Autoimmune↗

PubMed2005

[Psoriasis vulgaris exacerbated by imatinib therapy in chronic myelogenous leukemia].

Administration of imatinib exacerbated psoriasis vulgaris in a case of chronic myelogenous leukemia (CML). After the cessation of imatinib therapy, the psoriasis was alleviated. Upon readministration of imatinib, the psoriasis worsened despite the improvement of hematological and cytogenetic findings in the CML. Psoriasis is known to be an autoimmune skin disease characterized by Th1 cell-mediated hyperproliferation of keratinocytes, and the type 1 helper T (Th1) cell subset increased with imatinib therapy. Thus, the exacerbation of psoriasis was likely due to the increase in Th1 cells associated with imatinib therapy.

Antineoplastic Agents↗

PubMed2005

[Serum CA125 level associated with disease activity in a patient with follicular lymphoma].

We encountered a case of follicular lymphoma in a patient with high levels of serum CA125. On examination, abdominal lymph node swelling and hepatosplenomegaly were observed. The CA125 level decreased during treatment and was normalized at complete remission. An immunohistochemical assay of the lymphoma cells, however, failed to demonstrate any CA125. Several reports have described that CA125 might be produced by mesothelial cells in response to cytokines released by the lymphoma cells, and increased levels of CA125 have been significantly associated with abdominal involvement. It is possible that CA125 will become a useful marker in the observation of the progression of malignant lymphoma in the abdomen.

Adult↗

PubMed2004

A case of probable hydroxyapatite deposition disease (HADD) of the hip.

We describe a patient with acute calcific periarthritis in an unusual site, the ilio-femoral ligament. The clinical findings in this patient resembled those of septic arthritis. T2*-weighted images with gradient field echo clearly showed foci of low signal intensity in this region, corresponding to the calcification shown on plain radiographs, and increased signal intensity around the foci, representing edema. These signal intensities were diagnostic of the disease.

Acute Disease↗

PubMed2004

Decrease of Smad4 gene expression in patients with essential thrombocythaemia may cause an escape from suppression of megakaryopoiesis by transforming growth factor-beta1.

Essential thrombocythaemia (ET) is characterized by the abnormal and sustained proliferation of megakaryocytes. The mechanism for this lineage-specific expansion in ET, remains unclear. We have previously reported that transforming growth factor-beta1 (TGF-beta1) is involved in negative feedback regulation of megakaryopoiesis in both healthy volunteers (HV) and patients with idiopathic thrombocytopenic purpura (ITP). The present study found that megakaryocyte colony-forming units (CFU-MK) of ET patients were less sensitive to TGF-beta1 than those of HV. The expression of Smad4 (Sma- and Mad-related protein-4) in CFU-MK of ET patients was reduced in comparison with that of HV. Finally, to confirm that the impaired TGF-beta1 sensitivity was caused by reduced expression of Smad4, we examined Smad4-transfected CFU-MK from ET patients in the presence of TGF-beta1, and verified that the transfectants were indeed as susceptible as CFU-MK from HV to TGF-beta1. Thus it was surmised that one of the mechanisms for impaired sensitivity of CFU-MK to TGF-beta1 is the reduced expression of Smad4.

Adult↗

PubMed2004

[Successful induction and complete improvement of myelofibrosis and erythema nosodum with cladribine in a case of hairy cell leukemia].

The patient was a 45-year-old male who had been diagnosed with pancytopenia in 1998 at another hospital, where he continued treatment for idiopathic thrombocytopenic purpura (ITP) as an outpatient. After atypical lymphocytes were detected in his peripheral blood, he was admitted to our hospital for further examination in April 2002. Tests results revealed the additional existence of pancytopenia, splenomegaly, bone marrow fibrosis and erythema nodosum, in addition to the findings of surface marker. Tartrate resistant acid phosphatase (TRAP) staining and scanning electron microscopy of peripheral blood lymphocytes indicated hairy cell leukemia. After administration of cladribine (0.09 mg/kg) for 7 days, complete remission was obtained, with bone marrow fibrosis and erythema nodosum also being completely improved.

Antineoplastic Agents↗

PubMed2003

Interaction between leukemic-cell VLA-4 and stromal fibronectin is a decisive factor for minimal residual disease of acute myelogenous leukemia.

Bone-marrow minimal residual disease (MRD) causes relapse after chemotherapy in patients with acute myelogenous leukemia (AML). We postulate that the drug resistance is induced by the attachment of very late antigen (VLA)-4 on leukemic cells to fibronectin on bone-marrow stromal cells. We found that VLA-4-positive cells acquired resistance to anoikis (loss of anchorage) or drug-induced apoptosis through the phosphatidylinositol-3-kinase (PI-3K)/AKT/Bcl-2 signaling pathway, which is activated by the interaction of VLA-4 and fibronectin. This resistance was negated by VLA-4-specific antibodies. In a mouse model of MRD, we achieved a 100% survival rate by combining VLA-4-specific antibodies and cytosine arabinoside (AraC), whereas AraC alone prolonged survival only slightly. In addition, overall survival at 5 years was 100% for 10 VLA-4-negative patients and 44.4% for 15 VLA-4-positive patients. Thus, the interaction between VLA-4 on leukemic cells and fibronectin on stromal cells may be crucial in bone marrow MRD and AML prognosis.

Animals↗

PubMed2003

Thrombopoietin concentrations in peripheral blood correlated with platelet numbers in two patients with thrombocytopenia by chronic graft-versus-host disease.

Thrombocytopenia is well known to be one of the clinical manifestations of chronic graft-versus-host disease (cGVHD). However, there exist cases in which the cause of thrombocytopenia has been unexplained. Recently, thrombopoietin (TPO) from bone marrow (BM) stromal cells and transforming growth factor (TGF)-beta from platelets and megakaryocytes have been identified as strong positive and negative regulators of megakaryopoiesis in vivo. We hypothesized that the decreased TPO production from BM could be one of the causes of thrombocytopenia in the patients with cGVHD. In the present study, therefore, TPO and TGF-beta concentrations in peripheral blood (PB) and BM were measured serially in two patients with acute leukemia who had received fully matched stem cell transplantation from relatives and subsequently developed extensive cGVHD with thrombocytopenia. The results showed that platelet numbers correlated well with the TPO concentrations, which were consistently higher in BM than in PB. The difference in TPO concentrations between BM and PB was decreased when the platelet levels were low, indicating that the amount of TPO production from BM decreased throughout the duration of thrombocytopenia. TGF-beta concentrations were normal during all periods in which measurements were carried out. Thus, our results suggest that one mechanism of thrombocytopenia in patients with cGVHD is low TPO production by BM cells.

Adult↗

PubMed2002

A stilbene synthase from Japanese red pine (Pinus densiflora): implications for phytoalexin accumulation and down-regulation of flavonoid biosynthesis.

Stilbene synthase (STS) and chalcone synthase (CHS) are plant-specific polyketide synthases that play key roles in the stilbenoid and flavonoid biosyntheses, respectively. We have recently isolated from Pinus densiflora three STS cDNAs (PDSTS1, PDSTS2, and PDSTS3) and one CHS cDNA (PDCHSX). We then heterologously expressed these cDNAs in Escherichia coli and characterized their properties. An unusual STS isozyme, PDSTS3, lacks the common C-terminal extension of STS because of a frame-shift mutation and shows the highest pinosylvin-forming activity among the STSs tested. Pinosylvin was shown to be a potent inhibitor of PDCHSX (K(i) = 6 microM) as well as PDSTS2 (K(i) = 13 microM), which presumably maintains the balance between the stilbenoid and flavonoid biosyntheses. PDSTS3 was insensitive to product inhibition. We identified PDSTS3 in the pine seedlings as well as full-length STS. The data provide evidence that PDSTS3 is involved in the potential regulation of the stilbenoid and flavonoid biosynthetic pathways in pine trees.

Acyltransferases↗

PubMed2002

Granulocyte-colony stimulating factor enhances the expression of transforming growth factor-beta mRNA in CD4-positive peripheral blood lymphocytes in the donors for allogeneic peripheral blood stem cell transplantation.

The degree of acute graft-versus-host disease (GVHD) after allogeneic peripheral blood stem cell transplantation (allo-PBSCT) has been observed to be, unexpectedly, of an equal level to that after bone marrow transplantation. To explain this phenomenon, we hypothesized that granulocyte-colony stimulating factor (G-CSF) administration may induce transforming growth factor (TGF)-beta producing T cells in the donors. Five donors received 10 microg/kg G-CSF subcutaneously for 4 days. The TGFbeta mRNA expression in CD4(+) cells as measured by real time reverse transcription-polymerase chain reaction increased after G-CSF administration. This elevation is considered to be one additive mechanism of repression of acute GVHD after allo-PBSCT.

Blood Donors↗

PubMed2002

Uterine adenocarcinoma in N-ethyl-N'-nitro-N-nitrosoguanidine-treated rats with high-dose exposure to p-tert-octylphenol during adulthood.

Since many risk factors are associated with the development of uterine adenocarcinomas in humans, the etiology is unclear in most cases, although it has been pointed out that estrogen may play essential roles. To clarify the effects of exposure to p-tert-octylphenol (OP), an environmental xenoestrogen, on uterine carcinogenesis, adult Donryu rats were initiated with a single intrauterine treatment of N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) at 11 weeks of age and exposed thereafter to 100 mg / kg OP by s.c. injection until 15 months of age. Adult ovariectomized (OVX) rats were also treated in a similar way. OP had no effect on occurrence of persistent estrus in middle age, although uterotrophic effects were obvious in OVX rats. At the termination, development of uterine adenocarcinomas was significantly increased in animals exposed to OP during adulthood. No tumors, but a few focal hyperplasias, developed in OVX rats. These findings suggest that OP has tumor-promoting effects on ENNG-treated endometrium of rats, possibly due to direct action on the uterus, as indicated by the uterotrophic effect when a high dose of OP was given. The results provide clues to the mechanisms of influence of hormonal disrupters on uterine carcinogenesis.

Adenocarcinoma↗