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Biomedical subjects

J Tamura

Publications and source records attributed to J Tamura.

At least 127 records · Page 7Linked to original sources
PubMed1994

Multiple autoantibody production in a patient with splenic lymphoma.

We report on a patient with splenic lymphoma of B-cell origin who developed autoimmune hemolytic anemia (AIHA). IgM lambda M-protein, IgM anticardiolipin antibody (ACA), and lupus anticoagulant (LA) were detected in the serum, and direct Coombs' test showed autoantibodies of the IgG1 and IgG2 subclasses on red blood cells (RBC). In in vitro culture, tumor cells isolated from the spleen produced only IgM ACA, which was enhanced by IL-6 but not by IL-4 or IL-5. The levels of ACA and LA decreased after splenectomy and chemotherapy; the strength of the direct Coombs' test, however, did not change. These findings indicated that in this patient the lymphoma cells produced IgM lambda ACA, but not autoantibodies of the IgG1 and IgG2 subclasses against RBC. It was also suggested that IL-6 might at least partially stimulate the production of ACA.

Anemia, Hemolytic, Autoimmune↗
PubMed1994

Tumour necrosis factor-alpha and interleukin 4 promote the differentiation of myeloma cell precursors in multiple myeloma.

The effects of tumour necrosis factor-alpha (TNF-alpha) and interleukin 4 (IL-4) on peripheral blood mononuclear cells (PBMC) from 36 patients with multiple myeloma (MM), 12 with monoclonal gammopathy of undetermined significance (MGUS) and 21 normal controls, were investigated. In 16/36 patients with MM, monoclonal plasma cells appeared after 4d in cultures containing TNF-alpha and IL-4. These changes were not observed in PBMC from patients with MGUS or from normal controls. These findings suggest that myeloma cell precursors do exist in the peripheral blood of MM patients and differentiate into plasma cells in the presence of TNF-alpha and IL-4. Based on these observations, we think that the variation in the number of myeloma cell precursors in peripheral blood could be used as a prognostic parameter of response to chemotherapy in myeloma patients. In addition, this assay may be useful to distinguish early-stage MM from MGUS.

Cell Differentiation↗
PubMed1994

Cyclic haemopoiesis at 7- or 8-day intervals.

We report a patient with severe anaemia and cyclic oscillations of reticulocyte and leucocyte counts, as well as serum iron (Fe), unsaturated iron-binding capacity (UIBC), ferritin, C-reactive protein (CRP) levels and temperature, at regular intervals of 7 or 8 d. After treatment with prednisolone, anaemia was corrected and the cyclic oscillations of these parameters ceased; whereas treatment with indomethacin, recombinant granulocyte-colony stimulating factor (G-CSF) and erythropoietin (Epo) were unsuccessful.

Adult↗
PubMed1994

Plasma membrane fluidity during regeneration and atrophy of the rat liver following portal branch ligation.

Dynamic changes in liver plasma membrane fluidity caused by regeneration and atrophy were assessed in rats following portal branch ligation (PBL). The portal branch, which perfuses 70% of the liver, was ligated with 5-0 prolene, and liver plasma membranes were isolated by ultracentrifugation. The membrane fluorescence polarization was measured as an index of membrane fluidity using 1,6-diphenyl-1,3,5-hexatriene (DPH) as the probe dye. In nonligated lobes, a significant decrease in fluorescence polarization was observed 12 and 24 h after PBL (0.171 +/- 0.004, p < 0.01 and 0.165 +/- 0.005, p < 0.001, respectively) as compared to the controls (0.181 +/- 0.002). The fluorescence polarization values then gradually returned to near control levels. In contrast, in the ligated lobes, the fluorescence polarization had increased by 12 hours after PBL (0.196 +/- 0.002, p < 0.01), and remained significantly elevated (p < 0.01) for up to 1 week after PBL, gradually returning to control levels within 3 weeks. The membrane composition was also evaluated by analyzing the cholesterol/phospholipid (C/P) ratio. A significant increase in the C/P ratio was detected in the ligated lobes 12 h and 3 days after PBL, but there was no significant difference in fluorescence polarization values between nonligated lobes and controls. These results suggest that alterations in membrane fluidity play an important role in the regenerative and atrophic processes of the liver following portal branch ligation.

Animals↗
PubMed1994

Suppressed natural killer cell activity in ulcerative colitis.

We describe a 31-year-old patient with ulcerative colitis who was successfully treated with prednisolone (PSL). Immunologic analyses were performed during the treatment course. Suppressed natural killer (NK) cell activity and increased levels of the CD4/CD8 ratio were observed on admission. Transient restoration of NK cell activity was obtained by PSL treatment. However, it returned to the initial low level in spite of the improvement of clinical symptoms. Possible mechanisms are discussed for involvement of the immune system in the pathogenesis of ulcerative colitis (UC).

Adult↗
PubMed1994

Decrease in serum ferritin level in a patient with HCV hepatitis and liver hemosiderosis by interferon-alpha.

We describe here a patient with chronic hepatitis C and liver hemosiderosis whose serum ferritin level was notably reduced by long-term interferon-alpha (IFN alpha) therapy. The decrease of the elevated serum ferritin level was considered to have been mostly obtained by the improvement of liver dysfunction. However, at the beginning of the therapy, in spite of alanine aminotransferase (ALT) improvement, his serum ferritin level increased transiently, and after cessation of IFN alpha therapy, the serum ALT increased again, but the serum ferritin had not increased. This indicates that IFN alpha has an effect on the iron-related measurement, partly due to improvement of hepatic status.

Alanine Transaminase↗
PubMed1993

Ultrastructure of plasma cells in a patient with J chain disease.

Ultrastructural analysis of plasma cells was performed in a 74-year-old female patient with J chain disease. By electron microscopy, various characteristic findings were observed: lobulated nuclei, multinuclei, single sac loop-like structures, flocculent filament-like substances, nuclear inclusion bodies, cytoplasmic inclusion bodies, and multilamellar bodies. Our prior studies pointed out a poor prognosis in myeloma patients with these findings.

Aged↗
PubMed1993

Ultrastructure of neutrophilic phagosome of autologous platelet in vivo in specific granule deficiency.

The ultrastructure of neutrophilic phagosomes containing autologous platelets in vivo from a woman with specific granule deficiency is described. This phagosome formation was observed only when she had developed pneumonia due to Staphylococcus aureus. Therefore, the phenomenon might be induced by severe bacterial infection under an abnormal neutrophilic condition accompanied by specific granule deficiency.

Adult↗
PubMed1993

Primary plasmacytoma of generalized lymph nodes: a long survivor.

Extramedullary plasmacytomas are occasionally seen in the course of multiple myeloma; however, primary plasmacytomas are unusual. Most of the primary plasmacytomas arise in the upper respiratory system, but a plasmacytoma of the lymph nodes is very rare. A case of a 56-year-old female with primary plasmacytoma in the lower mandibular, cervical, axillary, and para-aortic lymph nodes accompanied by IgA Kappa paraproteinemia is described. After ten courses of combination chemotherapy with cyclophosphamide and prednisolone, she obtained complete response. However, 6 years later, she had a relapse of plasmacytoma in the generalized lymph nodes. She received ten treatments of melphalan-prednisolone and again obtained complete response. She has remained well without chemotherapy or recurrent signs for 9 years. It is considered that conventional chemotherapy can be useful for primary plasmacytoma of generalized lymph nodes.

Female↗
PubMed1993

A new bioactive bone cement consisting of BIS-GMA resin and bioactive glass powder.

We have developed a bioactive bone cement consisting of silane-treated CaO-SiO 2-P 2O 5-CaF 2 glass powder as the filling particles and bisphenol-a-glycidyl methacrylate (BIS-GMA) diluted with triethylene-glycol dimethacrylate (TEGDMA) as the organic matrix. Histological examination demonstrated direct bonding between the cement and bone along the circumference of the cement at 4 weeks after implantation in rat tibia. The compressive strength and toughness of the cement were two and four times greater than those of polymethylmethacrylate (PMMA) cement, respectively. The inflammatory reaction of the skin caused by the new cement was not as intense as that for PMMA 3 days after subcutaneous implantation. This new cement may be applicable as a bioactive bone cement with high mechanical strength.

Animals↗
PubMed1993

Altered fluidity of liver plasma membranes following partial hepatectomy in rats.

The fluidity of liver plasma membranes was assessed during regeneration following partial hepatectomy in rats. Fluorescence polarization was measured using 1,6-diphenyl-1,3,5-hexatriene to evaluate the fluidity of liver plasma membranes. The fluorescence polarization value of liver plasma membranes of control rats was 0.189 +/- 0.005 (mean +/- SEM). The fluorescence polarization values decreased initially after a 70% hepatectomy [0.176 +/- 0.003 at 3 hr and 0.174 +/- 0.004 at 6 hr (P < 0.01)] at 3 and 6 hours, but then recovered to preoperative levels (0.181 +/- 0.004, 0.189 +/- 0.004, 0.189 +/- 0.003, 0.193 +/- 0.003, 0.200 +/- 0.002, 0.208 +/- 0.007, and 0.190 +/- 0.003 at 12, 24, 36, 48, 72, 96 hr, and 7 days, respectively). Flow cytometric analysis using anti-bromodeoxyuridine (BrdU) monoclonal antibody was used to investigate the cell kinetics of the regenerating liver after 70% hepatectomy. The proportion of S-phase incorporating BrdU was not increased at 6 or 12 hr, but it then increased to peak of 27.9 +/- 1.9% at 24 hr. Subsequently, at 48, 72, and 168 hr, the proportion decreased to 8.5 +/- 0.6, 5.9 +/- 0.3, and 1.0 +/- 0.1%, respectively. The ratio of phospholipid to cholesterol contents of liver plasma membranes following partial hepatectomy did not significantly change in spite of markedly altered membrane fluidity. Thus, the alteration of membrane function occurs in conjunction with the initiation of the regeneration process following partial hepatectomy. It is suggested that the alteration of membrane fluidity plays an important role in the homeostatic response for cell proliferation.

Animals↗
PubMed1993

Evaluation of increased serum ferritin levels in patients with hyperthyroidism.

To further elucidate the mechanism of increased serum ferritin levels in hyperthyroidism, the changes in erythrocytes and serum iron and total iron-binding capacity levels were examined in addition to serum ferritin levels in 13 hyperthyroid patients. The mean values of hemoglobin, red blood cells, and packed cell volume were increased by antithyroid therapy. While the serum levels of iron did not change, those of total iron-binding capacity increased significantly after achieving a euthyroid state. Increased serum ferritin levels returned to normal through antithyroid therapy. Furthermore, the serum ferritin levels of four anemic patients were significantly higher than those of nine nonanemic patients. Thus it is concluded that the increase in serum ferritin levels in patients with hyperthyroidism may be due to the direct action of thyroid hormones on its synthesis, while in some cases complicated with anemia impaired iron utilization by erythropoietic cells may also be involved.

Adult↗
PubMed1993

Change of paraprotein from IgG lambda to lambda chain in myeloma.

We describe a unique case of IgG lambda myeloma in which a plasma cell leukemia developed and the paraprotein changed from IgG lambda to lambda chain, the latter inducing fatal renal failure. In addition, J-chain was detected in the cytoplasm of the plasma cell leukemia cells.

Female↗
PubMed1993

Spurious macrocytosis associated with non-Hodgkin's lymphoma: report of two cases.

We report two rare cases of spurious macrocytosis (SM) associated with non-Hodgkin's lymphoma caused by cold agglutinin. SM was reversed, accompanied by the regression of lymphoma in case 1 but not in case 2, where the lymphoma was refractory to the chemotherapy. It is strongly suggested that lymphoma cells were related to the production of cold agglutinin and the cause of SM.

Adult↗
PubMed1993

MCNU in the treatment of essential thrombocythemia--a pilot study.

The efficacy of a single dose of MCNU 150 mg was evaluated in nine symptomatic patients with essential thrombocythemia (ET). As the platelet counts increased during the following 4 weeks, an extra dose of 100 mg of MCNU was administered to three patients. All patients had thrombotic or hemorrhagic complications. Seven patients responded. The mean platelet count decreased to below 1.0 x 10(12)/l within 5 weeks; it reached its lowest level (0.35 x 10(12)/l) at 6 weeks and became stable at less than 1.0 x 10(12)/l without further therapy for 12 weeks in all patients. Thrombotic and hemorrhagic complications ameliorated within 4 weeks in all patients. Our study indicates that MCNU acts as a platelet-reducing agent in patients with ET.

Adult↗
PubMed1993

Myelodysplastic syndrome with eosinophilia in bone marrow. Gunma Haematology Study Group.

Clinical features were investigated in 114 patients with de novo myelodysplastic syndrome (MDS) diagnosed over the past 10 years, and eight cases (7%) were complicated with eosinophilia in the bone marrow. Two patients had refractory anaemia (RA), five had RA with excess of blasts (RAEB), and one had RAEB in transformation. Their bone marrow cells exhibited tri-lineage dysplasia and morphological abnormalities in eosinophils. Cytogenetics revealed major karyotype abnormalities (MAKA) in five patients. Survival durations were significantly shorter than those of other MDS patients. Our study suggests that marrow eosinophilia in MDS is strongly related to the coexistence of MAKA.

Aged↗