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A Masumoto

Publications and source records attributed to A Masumoto.

At least 37 records · Page 2Linked to original sources
PubMed1996

Clinical significance of LEA-1 expression in adult acute myeloid leukemia.

In this study, we examined expressions of several adhesion molecules (AdMs), i.e. leukocyte function antigen-1 (LFA-1: CD11a/CD18), Hermes homing receptor (CD44) and intercellular adhesion molecule-1 (ICAM-1: CD54), on leukemia cells from 51 adult patients with newly diagnosed acute myeloid leukemias (AMLs) to elucidate clinical significance of these AdM expressions. Those expressions in lymphoid malignancies have been correlated with tumor evolutions, but CD44 was detected in all the AML cases examined and CD54 expression did not associate with their clinical characteristics or outcomes. However, we found that LFA-1 expressions significantly correlated with splenomegaly, resistance to induction chemotherapies and short survival periods in AML patients.

Acute Disease↗
PubMed1996

Decay-accelerating factor (DAF, CD55)-negative T lymphocytes in the peripheral blood of Sjögren's syndrome patients.

OBJECTIVE: To clarify possible associations of decay-accelerating factor (DAF, CD55), expressed on circulating lymphocyte subsets and other hematologic cells, with corresponding cytopenias observed in primary Sjögren's syndrome (SS). METHODS: DAF expression on peripheral blood (PB) cells was determined in 21 patients with SS and 11 healthy controls by single or 2 color flow cytometry. RESULTS: In the PB from SS patients, anemia, monocytopenia, neutropenia, and lymphocytopenia were observed. Compared to the controls, the percentages of DAF-negative cells were higher in CD4+ and CD8+ T cell subsets from SS patients, but the expression of DAF was similar in the other PB cells, including CD19+ B cells, CD56+ NK cells, monocytes, granulocytes, and erythrocytes. The percentages of DAF-negative cells among the CD4+ and CD8+ cells were positively correlated in SS patients, but the numbers of cells in both subsets were decreased in those patients being treated with prednisolone. However, these proportional changes are thought to reflect a decrease in the numbers of DAF-positive CD4+ and CD8+ cells, because the absolute numbers of circulating DAF-positive CD4+ and CD8+ cells, but not DAF-negative cells, were significantly decreased in SS patients. In addition, DAF-negative cells were detectable in both CD45RA+ (naive) and CD45RO+ (memory) T cells from healthy individuals, and the expression of DAF was remarkably increased in both subsets after in-vitro activation with concanavalin-A. CONCLUSION: DAF-negative cells are proportionally increased among circulating CD4+ and CD8+ T cells in SS patients, although such changes are due to decreased numbers of DAF-positive cells within each subset. When considering previous observations, the DAF-negative CD4+ and CD8+ cells probably belong to activated T cell subsets in both SS patients and controls. However, the patterns of DAF expression seemed to be different between activated T cells recognized in the PB, and those induced by in vitro-stimulation.

Adult↗
PubMed1994

[Clinical studies of a newly developed miconazole preparation for intravenous drip infusion (MJR-1761) in hematologic disease patients with deep-seated fungal infections].

The efficacy and safety of a newly developed miconazole preparation (MJR-1761) for intravenous drip infusion were evaluated in 22 patients with hematological diseases complicated by documented or suspected deep-seated fungal infections. They consisted of 15 patients with fungemia, 2 patients with pulmonary mycosis, and 5 patients with mycosis of the digestive tract. Of the 5 patients, 3 had a complication of fungemia and 1 a complication of urinary tract mycosis. Of the 22 patients, 21 were clinically evaluable. All the patients were included in safety evaluation. The effective rate was 86% (18/21) when moderately improved or better evaluations were included, and the usefulness rate was 81% (17/21) when moderately or more useful evaluations were taken into consideration. Side effects occurred in 4 patients, and abnormal laboratory values were obtained in 4 patients. All these changes, which were previously reported, improved after the discontinuation of the treatment. The results presented indicate that the miconazole intravenous drip infusion solution used in this study is as effective as conventional similar preparations. Since the infusion solution need not be diluted immediately before use, it is simple to use, and its safety may be highly rated. The purpose can be met with less volume of solution per use than before because the preparation contains as much as 200 mg of miconazole in 75 ml of solution. This preparation seems to lend itself better to clinical application than conventional similar infusion solutions.

Adult↗
PubMed1994

Circadian variations and prednisolone-induced alterations of circulating lymphocyte subsets in man.

We determined the circadian variations and prednisolone (PSL)-induced alterations of circulating lymphocyte subsets in 10 healthy adults by two-color flow cytometry using monoclonal antibodies to various lymphocyte subsets in order to collect fundamental data for monitoring of the subsets in clinical practice. This study first examined the changes of CD5+ B cells, gamma delta+ or gamma delta-T cells, activated (HLA-DR+) CD4+ or CD8+ cells, CD11b+ or CD11b-CD8+ cells, and natural killer (NK) cell subsets (CD16+CD57-, CD16+CD57+, CD16-CD57+), in addition to other subsets described before. Compared with the base line values obtained at 9:00 (AM) on day 1, lymphocytes, total B cells, CD5+ B cells, total T cells, gamma delta-T cells, CD4+ cells, activated CD4+ cells, CD45RA-CD4+ cells, and activated CD8+ cells were significantly increased at 20:00 (PM). However, the numbers of CD45RA+CD4+ cells, CD11b+ or CD11b-CD8+ cells and three NK cells subsets did not show significant circadian variations. After oral PSL (30 mg), which was given at 7:00 (AM) on day 2, lymphocytes and almost all lymphocyte subsets, except for CD16+CD57- cells, were significantly decreased; these changes recovered between 13 and 26 hours after PSL administration. The circadian variations and PSL-induced alterations of lymphocyte subsets were relatively comparable, but PSL administration cause a decrease in a wider range of lymphocyte subsets including relatively corticosteroid-resistant subsets such as CD45RA+CD4+ cells, CD8+ cell and NK cell subsets.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Effects of cytarabine ocfosfate on colony-stimulating factor in myelodysplastic syndrome with monosomy 7].

A 42-year-old man was admitted to our hospital because of pancytopenia in April 1992. A diagnosis of refractory anemia was made. The karyotype was normal male type on the initial study. Subcutaneous administration of granulocyte colony-stimulating factor (G-CSF) initially increased the peripheral neutrophil count, bat in January 1993, although blast cells did not increase, neutrophils had decreased in spite of the continuation of G-CSF administration. Chromosome analysis showed 46XY, +Y, -7 at this point. By adding 50 mg of cytarabine ocfosfate (SPAC) daily, the peripheral neutrophil count again rose dramatically. However, anemia, thrombocytopenia and the chromosomal abnormality were unchanged. These results indicate that SPAC may upregulate the effect of G-CSF on granulopoiesis in patients with myelodysplastic syndrome.

Adult↗
PubMed1994

[Pure red cell aplasia induced by erythromycin and furosemide effects on in vitro erythroid colony forming unit (CFU-E)].

A 84-year-old man was treated with antibiotics including erythromycin and a diuretic (furosemide) because of acute heart failure and pneumonia. During the treatment, he developed moderate anemia (Hb 8.7g/dl). His anemia improved after the treatment. He again developed marked anemia (Hb 6.3g/dl) during the second treatment with erythromycin and furosemide and received blood transfusions. Bone marrow aspiration study revealed severe erythroid hypoplasia (0.2%). He was referred to our hospital, but he was not treated because his hemoglobin levels and reticulocyte count increased (80%) and his bone marrow showed increased erythroblasts (41.5%). His anemia gradually improved without any treatment. We diagnosed the case as drug-induced pure red cell aplasia (PRCA). We cultured bone marrow cells obtained from the present case and four normal healthy volunteers by a plasma clot method to determine the effects of two drugs on the number of erythroid colony forming unit (CFU-E). Furosemide strongly inhibited the CFU-E colony formation in the patient, but the inhibition effect of erythromycin was moderate. Furthermore, CFU-E was markedly suppressed by a combination of erythromycin and furosemide in both patient and control materials. These results indicate that both furosemide and erythromycin were related to the occurrence of PRCA in this patient.

Aged↗
PubMed1993

Stimulation of DNA synthesis in hepatocytes by hepatocyte growth factor bound to extracellular matrix.

Hepatocyte growth factor (HGF) purified from human placenta was specifically bound to a component in ECM secreted from lung fibroblasts, hepatocytes, and nonparenchymal liver cells. HGF was also bound to a component in basement membrane matrigel. The rate of DNA synthesis in hepatocytes cultured on the HGF-bound ECM was 4-7 times that of control hepatocytes. When ECM-coated dishes were pretreated with heparinase and heparitinase prior to binding of HGF, the stimulation decreased remarkably. A considerable decrease in the stimulation was observed following the washing of HGF-bound ECM with 1 M NaCl. We propose, based on these observations, that HGF bound to the ECM component present in Disse's space functions in regeneration following hepatic injury.

Animals↗
PubMed1993

Multiple activation states of VLA-4. Mechanistic differences between adhesion to CS1/fibronectin and to vascular cell adhesion molecule-1.

We examined the effects of a stimulatory anti-beta 1 mAb (TS2/16) and different divalent cations on VLA-4-mediated cell adhesion to vascular cell adhesion molecule-1 (VCAM-1), to the fibronectin-derived CS1 peptide, and to larger fibronectin fragments. Using optimal binding conditions (in the presence of mAb TS2/16 and 1.0 mM Mn2+), the levels of VLA-4-mediated adhesion to VCAM-1 and to CS1 peptide were virtually indistinguishable, and half-maximal inhibition of adhesion to both ligands was achieved using similar levels of an anti-alpha 4 antibody. However, using suboptimal adhesion conditions, two critical differences between adhesion to CS1 peptide (or larger fibronectin fragments) and VCAM-1 were consistently observed. First, stimulation by added mAb TS2/16 had a substantially greater effect on adhesion to CS1 than to VCAM-1 and second, Ca2+ was much less able to support adhesion to CS1 than to VCAM-1. These two differences between adhesion to CS1 peptide and to VCAM-1 were most obvious among cell lines which synthesized inactive or partly active VLA-4 but were not obvious for fully active VLA-4. Together, these results not only reveal crucial differences in the mechanisms of VLA-4 binding to its two ligands, but also lead to increased understanding of the variable activation states of VLA-4. The differential ability to utilize Ca2+ displayed by VLA-4 in different states of activation and the activation of inactive or partly active VLA-4 by the addition of Mn2+ both point to divalent cation sites playing an essential role in determining VLA-4 regulation and ligand specificity.

Antibodies, Monoclonal↗
PubMed1993

Mutation of putative divalent cation sites in the alpha 4 subunit of the integrin VLA-4: distinct effects on adhesion to CS1/fibronectin, VCAM-1, and invasin.

To investigate the functional significance of putative integrin divalent cation binding sites, several mutated alpha 4 subunit cDNAs were constructed. Mutants contained the conservative substitution of Glu for Asp or Asn at the third position in each of three putative divalent cation sites. Transfection of wild-type or mutated alpha 4 into K562 cells yielded comparable expression levels and immunoprecipitation profiles. However, for all three alpha 4 mutants, adhesion to CS1/fibronectin was greatly diminished in either the presence or absence of the stimulatory anti-beta 1 mAb TS2/16. Constitutive adhesion to vascular cell adhesion molecule (VCAM) 1 was also diminished but, unlike CS1 adhesion, was restored upon TS2/16 stimulation. In contrast, adhesion to the bacterial protein invasin was minimally affected by any of the three mutations. For each of the mutants, the order of preference for divalent cations was unchanged compared to wild-type alpha 4, on CS1/fibronectin (Mn2+ > Mg2+ > Ca2+), on VCAM-1 (Mn2+ > Mg2+ = Ca2+) and on invasin (Mg2+ = Ca2+). However for the three mutants, the efficiency of divalent cation utilization was decreased. On VCAM-1, 68-108 microM Mn2+ was required to support half-maximal adhesion for the mutants compared with 14-18 microM for wild-type alpha 4. These results indicate (a) that three different ligands for VLA-4 show widely differing sensitivities to mutations within putative divalent cation sites, and (b) each of the three putative divalent cation sites in alpha 4 have comparable functional importance with respect to both divalent cation usage and cell adhesion.

Adhesins, Bacterial↗
PubMed1993

Reactive lymphoid hyperplasia of the liver.

A patient with reactive lymphoid hyperplasia of the liver was symptom free and had no underlying disease except for diabetes mellitus. The hepatic tumor was found by ultrasound examination at routine checkup. The preoperative diagnosis of the tumor was unsuccessful despite various radiological examinations. Histological examination of the resected tumor showed that it was composed of benign-appearing lymphocytic proliferations forming lymphoid follicles that included numerous germinal centers. The germinal center was mainly composed of B-cell marker, L26-positive lymphocytes, but a few T cells were also found. Lymphocytes surrounding germinal centers were mainly T-cell marker, UCHL1-positive T-cells, and a small number of B cells. The B cells in the lymphoid follicles were stained for both kappa and lambda light chains at equal frequency, indicating polyclonal and benign nature. A diagnosis of reactive lymphoid hyperplasia of the liver seems justified.

B-Lymphocytes↗
PubMed1993

Characterization of a hepatocyte growth factor derived from nonparenchymal liver cells.

A growth factor stimulating DNA synthesis of adult rat hepatocytes in primary culture was found in the conditioned medium after culturing nonparenchymal liver cells (NPC). Adding heparin to the NPC cultured medium stimulated the growth-factor secretion from NPC. The growth factor was secreted mainly by Kupffer cells. The partially purified growth factor from the NPC appeared to be related to the HGF isolated from platelets according to three criteria: (a) binding to Heparin-Sepharose and eluting at about 0.65 M NaCl, (b) having a Mr of about 70 kDa, (c) having an immunoreactivity to antibody against rat platelet-derived HGF. Adding heparin to the NPC cultured medium also resulted in protection of the growth factor from heat- and acid-inactivation, but the direct interaction of heparin with the partially purified growth factor did not lead to such protection. Perfusion of normal adult rat livers with Hanks' solution containing 1 M NaCl in situ led to the release of large amounts of hepatocyte growth factor (10). These findings suggest that the hepatocyte growth factor derived from NPC binds to ECM between the layer of hepatocytes and endothelial cells forming the sinusoids in normal adult rat liver and that this may play a role in stabilization and maintaining the pool of HGF, which functions to constantly supply HGF in the setting of liver regeneration.

Animals↗
PubMed1993

[Changes of bone marrow MRI pattern in aplastic anemia before and after bone marrow transplantation].

In order to evaluate the usefulness of magnetic resonance imaging (MRI) in estimating bone marrow cellularity, we performed T1-weighted MRI of the lumbar vertebral marrow in two patients with severe aplastic anemia, before and after bone marrow transplantation (BMT). High signal intensity was detected in the bone marrow before BMT, but the bone marrow pattern of MRI became normal after BMT. MRI seems to be effective for evaluating bone marrow cellularity and recovery, and for monitoring therapeutic effects in patients with aplastic anemia before and after treatment with BMT.

Adult↗
PubMed1993

[Refractory acute myelogenous leukemia successfully treated with a continuous infusion chemotherapy of low dose aclarubicin and cytosine arabinoside: a case report].

A 44-year-old female with refractory acute myelogeneous leukemia had experienced an early relapse after a third complete remission (CR) with combination chemotherapy (BHAC-AMP) using daily one-shot infusion of 20 mg aclarubicin (ACR). Further treatments including intermediate dose of cytosine arabinoside (Ara-C) were not effective. After treatment with a continuous administration of low dose ACR (9 mg/day) and Ara-C (21 mg/day) for 14 days she entered a fourth CR. The mechanism of this treatment relates to both cell-killing and differentiation effects on leukemic cells.

Aclarubicin↗
PubMed1993

[A case of intrahepatic cholestasis following with adult respiratory distress syndrome].

A 58 year old man with arthralgia had been treated with antiinflammatory drugs since November, 1987. On March 1988, he was admitted to a local hospital because of jaundice. On April 18, exploratory laparotomy was done to look for the cause of continued jaundice. Macro-pathological and micropathological findings of the liver were compatible with those of intrahepatic cholestasis. On April 29, he was transferred to Kyushu University Hospital because of persistent jaundice. Physical examination showed jaundice, tachypnea and low grade fever. Laboratory examination showed elevated level of serum bilirubin, marked hypoxia and endotoxemia. Plain chest radiogram revealed ground-glass appearance in bilateral lung fields. He was diagnosed to be complicated with adult respiratory distress syndrome (ARDS). Glucocorticoid therapy and oxygen administration were started immediately. But pulmonary fibrosis developed and he died of respiratory failure. Histological findings of lung necropsy specimen were compatible with those of ARDS. These data strongly suggested that endotoxemia and reticuloendothelial dysfunction due to intrahepatic cholestasis had played important roles to develop ARDS.

Cholestasis, Intrahepatic↗
PubMed1992

Regulation of differentiation and proliferation of rat hepatocytes by lactose-carrying polystyrene.

We noticed that hepatocytes recognize the structure of oligosaccharides via asialoglycoprotein receptors and synthesized lactose-carrying styrene polymer (PVLA) as an asialoglycoprotein model. We found that the regulation of differentiated function and proliferation of hepatocytes that were cultured on polystyrene dishes can be achieved by varying the amount of PVLA coated on the dishes. The 3H-thymidine uptake of cultured hepatocytes is low for cells cultured on dishes coated with high amounts of PVLA in which the hepatocytes are round and is highest for those cultured on dishes with a low PVLA coating level in which the hepatocytes are spread in shape. Moreover, bile acid release as a typical differentiated function of hepatocytes was maintained at higher levels in hepatocytes attached on dishes coated with a high level of PVLA. Our results indicated that regulation of differentiated function and proliferation in hepatocytes could be achieved by specific ligand-mediated recognition of microscopic surface structure. Thus, it may be possible to regulate proliferation and differentiation of hepatocytes by design of the culturing substrata.

Animals↗