Biomedical subjects
K Oshimi
Publications and source records attributed to K Oshimi.
[Antiphospholipid antibody-associated hemophagocytic syndrome].
Autoimmune diseases such as systemic lupus erythematosus (SLE) are known to be causative disorders of reactive hemophagocytic syndrome (HPS). We recently encountered a case of HPS associated with the presence of antiphospholipid antibodies (aPL). This patient showed severe thrombocytopenia (0.2 x 10(4)/microliter) and moderate anemia (Hb; 7.6 g/dl). Bone marrow smears showed normal cellularity and an increase in mature-looking histiocytes scattered among the hematopoietic cells, which accounted for approximately 3% of all nucleated cells and were distributed unevenly. These cells showed marked phagocytosis of hematopoietic cells, including megakaryocytes, erythroblasts, and a few neutrophils. In this patient, there is no possible causative factor of HPS (such as viral infection, lymphoma, and systemic lupus erythematosus) except the presence of aPL. There have been no previously reported cases describing the relationship between aPL and HPS. This case indicate that attention should be given to the possibility that certain patients with aPL-associated cytopenia may display accompanying intramedullary hemophagocytic phenomena.
[Efficacy and safety of cefozopran (CZOP) monotherapy and combination therapy with CZOP and amikacin (AMK) for infections accompanying hematological diseases].
We evaluated efficacy and safety of monotherapy with CZOP (1-2 g x 2/day) and combination therapy with CZOP (1-2 g x 2/day) and AMK (200 mg x 2/day) for infections in patients with hematological diseases. Efficacy was evaluated in 71 patients of monotherapy group and 70 patients of combination therapy group. Underlying diseases were mostly leukemia and lymphoma. Infections included sepsis, suspected sepsis, pneumonia and so on. Efficacy in CZOP monotherapy was excellent in 21 patients (31.3%), good in 23 patients (34.3%), fair in 5 patients (7.5%) and the efficacy rate was 65.7%. On the other hand, in combination therapy, each was 14 patients (21.2%), 23 patients (34.8%), 12 patients (18.2%) and the efficacy rate was 56.1%. Side effects such as eruption were noted in 2 patients. Abnormal laboratory findings were noted in 9 patients. All side effects as well as abnormal laboratory findings were minimal. It was concluded that CZOP monotherapy was effective in the treatment of various infections accompanying hematological diseases.
[Idiopathic plasmacytic lymphadenopathy with polyclonal hyperimmunoglobulinemia and pleural effusion].
A 56-year-old man was admitted for further evaluation of mediastinal lymphadenopathy and left pleural effusion. A blood test revealed polyclonal hypergammaglobulinemia with an elevated erythrocyte sedimentation rate and level of C-reactive protein. Chest computed tomography disclosed bilateral hilar and multiple mediastinal lymph-node swelling and bilateral pleural thickening accompanied by a moderate amount of left pleural effusion. Biopsy specimens from mediastinal lymph nodes and the right pleura were obtained under video-assisted thoracoscopy. Histology on microscopic examination demonstrated mature plasma cells and lymphocyte infiltration in the conserved lymph-node structure and the pleura, suggesting a diagnosis of idiopathic plasmacytic lymphadenopathy (IPL) with polyclonal hyperimmunoglobulinemia. Interestingly, IL-6 was elevated in the pleural effusion but normal in serum. This was a rare and instructive case of IPL accompanied by pleural effusion that was considered to be an important determinant of the clinical spectrum of the disease.
[CD8-positive diffuse large B-cell lymphoma].
In May, 1998, a 63-year-old woman was admitted for treatment of relapsed malignant lymphoma. In March 1997, a diagnosis of diffuse large B-cell lymphoma(DLBL), clinical stage IIISE A, was made from a biopsy specimen of the tumor in the left buccal mucosa. Six cycles of CHOP regimen were given, and complete remission was achieved. However, relapse of the lymphoma was suspected, and the patient was transferred to our hospital. On admission, a right tosillar mass, 8 mm in diameter, was found, and a biopsy showed DLBL. The immunophenotype of the lymphoma cells was CD3- CD4- CD5- CD8+ CD10- CD19+ CD20+ CD23- CD25+ IgL (lambda)+, and dual staining confirmed that the cells were CD8+ and CD19+. The patient was an HTLV-1 carrier, but monoclonal integration of HTLV-1 proviral DNA into the lymphoma cells was not detected. She was diagnosed as having CD8+ DLBL, clinical stage IA. Because she responded to salvage chemotherapy, autologous peripheral blood stem cell transplantation was performed and complete remission was obtained. To our knowledge, this is the first report of CD8+ DLBL.
[Cytomegalovirus mononucleosis with severe thrombocytopenia].
In October 1998, a 37-year-old man was admitted because of petechiae and thrombocytopenia following flu-like symptoms. On admission, there were numerous petechiae on the back and extremities. The WBC count was 3,700/microliter with 3% atypical lymphocytes, the lymphocyte CD4/CD8 ratio 0.37, and the platelet count 1,000/microliter. Mild splenomegaly was detected by CT. Results of blood chemistry and coagulation tests were normal. A bone marrow aspirate was normocellular with no signs of dysplasia, and the megakaryocyte count was normal. The patient was initially diagnosed as having virus infection-associated thrombocytopenia. Steroid therapy was started immediately, and the platelet count rose to 15 x 10(4)/microliter on day 21. The PA-IgG level was 652 ng/10(7) platelets. Mild liver dysfunction developed, and atypical lymphocytes increased in number thereafter. Because IgM anti-cytomegalovirus (CMV) antibody (Ab) was positive and IgG CMV Ab was negative, a diagnosis of CMV mononucleosis was made. Gancyclovir was therefore started. Four months later, steroid therapy was discontinued, and partial remission has since been maintained. In healthy individuals, CMV infection is usually latent, and the development of mononucleosis is rare. So far, 11 cases of CMV-induced mononucleosis associated with severe thrombocytopenia have been reported in immunocompetent adults.
[Granular lymphocyte-proliferative disorders, lymphoproliferative disease of granular lymphocytes].
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[Evans syndrome].
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[Pernicious anemia].
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[Autoimmune myelodysplasias].
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P-glycoprotein expression on normal and abnormally expanded natural killer cells and inhibition of P-glycoprotein function by cyclosporin A and its analogue, PSC833.
P-glycoprotein (P-gp), a transmembrane efflux pump encoded by the MDR1 gene, has been found to be expressed in many normal bone marrow and peripheral blood cells. Among normal leukocytes, CD3(-)CD16(+) or CD3(-)CD56(+) lymphocytes, ie, natural killer (NK) cells, express relatively high levels of P-gp, but little is known about P-gp in abnormally expanded NK cells. In this study, we examined the expression and activity of P-gp on NK cells derived from three normal donors, six patients with indolent NK cell-lineage granular lymphocyte-proliferative disorder (NK-GLPD), three patients with aggressive NK cell tumors (one NK cell leukemia and two nasal NK cell lymphoma), and two NK cell lines. By flow cytometric analysis using the monoclonal antibody (MoAb) MRK16 and rhodamine 123 dye (Rh123), P-gp expression and the efflux of Rh123 were found in all NK samples except one NK cell line. The Rh123 efflux of NK cells was inhibited by cyclosporin A (CsA) and its analogue PSC 833, but the aggressive NK tumor cells were less inhibited than were the other NK cells. The percent inhibition of efflux in the normal NK cells, indolent NK-GLPD cells and aggressive NK cell tumors was 81.8% +/- 0. 9%, 93.4% +/- 3.1% and 36.9% +/- 11.7%, respectively, by 1 micromol/L CsA, and 80.2% +/- 3.6%, 91.7% +/- 2.6% and 32.7% +/- 10. 1%, respectively, by 1 micromol/L PSC833. In reverse transcription-polymerase chain reaction (RT-PCR) analysis, the low inhibitory effect of P-gp modulators in aggressive NK cell tumors did not correlate to the expression level of MDR1 gene, multidrug resistance-associated protein gene, or human canalicular multispecific organic anion transporter gene. This phenomenon could be related to the presence of other transporters or to unknown cellular or membrane changes. Some patients with NK cell tumors have been reported to show a highly aggressive clinical course and to be refractory to chemotherapy, and this could be related to the expression of P-gp on NK cells. Our results suggest that, although the inhibitors for P-gp have been used in combination with chemotherapy in some hematologic tumors, these inhibitors may be less effective against aggressive NK cell tumors.
A metalloproteinase inhibitor prevents acute graft-versus-host disease in mice after bone marrow transplantation.
Tumor necrosis factor (TNF) and Fas ligand (FasL) have been implicated in the pathogenesis of graft-versus-host disease (GVHD), which is a major complication after allogeneic bone marrow transplantation. We have examined the ameliorating effect of a metalloproteinase inhibitor (KB-R7785) that inhibits TNF-alpha and FasL release in a murine acute GVHD model after bone marrow transplantation. Administration of KB-R7785 to irradiated (BALB/c x C57BL/6) F1 mice that received C57BL/6 bone marrow cells and spleen cells reduced the mortality and weight loss in association with minimal signs of GVHD pathology in the liver, intestine, and hematopoietic tissues. The KB-R7785 treatment did not affect hematopoietic reconstitution by donor cells. Therefore, KB-R7785 could be a potent therapeutic agent for GVHD after bone marrow transplantation.
All-trans retinoic acid-induced vasculitis and hemonecrosis of the ileum in a patient with acute promyelocytic leukemia.
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Inhibition of p34cdc2 dephosphorylation in DNA damage- and topoisomerase II inactivation-induced G2 arrests in HL-60 cells.
Doxorubicin induces DNA breakage by stabilizing a cleavable topoisomerase II-DNA complex. In contrast, topoisomerase II catalytic inhibitor ICRF-193 and uncoupling inhibitor aclarubicin interfere with the cleavable complex formation. We analysed combination effects of these drugs using two-dimensional flow cytometry of DNA content and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labelling assay. Both ICRF-193 and aclarubicin attenuated the cytotoxic effect of doxorubicin on HL-60 cells (85% and 46% maximum reduction, respectively), which suggested that doxorubicin exerts its cytotoxic effect at least partially through the topoisomerase II-dependent DNA cleavage. Doxorubicin and ICRF-193 both induced G2 arrest in HL-60 cells, by which they may have reduced the cytotoxic effect of vincristine. Indeed, although ICRF-193 inhibited doxorubicin-induced apoptosis, ICRF-193 and doxorubicin cooperated in arresting HL-60 cells at G2 phase. These results indicated that G2 arrest was caused not only by DNA damage but also through a DNA damage-free, topoisomerase II inactivation-induced pathway. Western blot analysis showed that both types of G2 arrest were mediated by the inhibition of p34cdc2 dephosphorylation.
A case of fungemia due to Candida krusei.
A forty-eight-year old male diagnosed with acute lymphocytic leukemia was further complicated by Candida krusei fungemia despite introduction of fluconazole prophylaxis during antileukemic therapy. The fungemia subsided after intravenous amphotericin B therapy followed by itraconazole therapy. Multiple ulcerative lesions and a carcinoid lesion were observed in the transverse colon, and it was thought that the C. krusei had invaded from the ulcerative lesions. Azole antifungal agents, especially fluconazole, have frequently been used for therapy and the prophylaxis of fungal infections. Though infections due to fluconazole-resistant Candida species such as C. krusei are a growing problem, in the hematology division of our hospital there is no evidence of an increasing incidence of C. krusei fungemia or an increasing rate of C. krusei in surveillance culture from admitted patients. However, future increases in infections due to fluconazole-resistant Candida species like C. krusei and C. glabrata are entirely possible, making it necessary to identify isolated fungi, perform susceptibility tests on antifungal agents against isolates, measure the serum concentrations of antifungal agents, and then to treat patients with the appropriate therapies.
[Primary splenic lymphoma with hypoplastic bone marrow].
A 44-year-old man was admitted because of persistent fever and pancytopenia. Because his bone marrow was hypoplastic and the karyotype of his marrow cells was normal, he was given a diagnosis of aplastic anemia, and treated with glucocorticoids and granulocyte colony-stimulating factor. Splenomegaly was later found and a splenectomy performed: pathological findings on resected tissue specimens disclosed non-Hodgkin's lymphoma, B-cell diffuse large. The patient was transferred to our hospital, where a bone marrow biopsy revealed lymphoma cells infiltrating his hypoplastic marrow. Complex chromosomal abnormalities were detected in marrow cells, but no lymphadenopathy was observed. A diagnosis of primary splenic lymphoma with infiltration of lymphoma cells into bone marrow was made, and chemotherapy was accordingly started. After multiple cycles of chemotherapy, the patient's marrow recovered to a normal state and his karyotype abnormalities disappeared. Six months later, pancytopenia reappeared and lymphoma cells were again detected in the patient's bone marrow. We reasoned that the hypoplastic state of his bone marrow was associated with the lymphoma, and that cytokines, including interferon-gamma, may have been responsible for this association.