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Biomedical subjects

K Toyama

Publications and source records attributed to K Toyama.

At least 289 records · Page 16Linked to original sources

Trisomy of chromosome 8 in myelodysplastic syndrome. Significance of the fluctuating trisomy 8 population.

Chromosome analyses were performed in five patients with myelodysplastic syndrome (MDS) who showed trisomy of chromosome 8 during the course of their disease. Four of these patients showed trisomy 8 at the diagnosis of MDS, and the remaining one had trisomy 8 when the leukemia phase developed. The proportion of bone marrow (BM) cells with trisomy 8 in the four patients who showed trisomy 8 at MDS diagnosis fluctuated, and this fluctuation was not related to the percentage of blasts in the BM or to progression of the disease. However, in two patients, metaphase cells with trisomy 8 disappeared when their anemic state improved, although leuko-thrombocytopenia was still present, suggesting that the decrease in the number of BM cells with trisomy 8 reflects hematologic features in some MDS patients. These findings indicate that trisomy 8 in our MDS patients was possibly not the primary event in the genesis of the disease, and that there may have been competition between a normal karyotype clone and a trisomy-8-positive clone. Our results further suggest that the presence of a clone with trisomy 8 is not always a sign of disease progression or of poor prognosis in MDS patients.

Adult↗

Restoration of cytogenetically normal marrow cells after remission of lymphoblastic crisis in a case of Ph positive CML treated with alpha-interferon.

A patient with Philadelphia (Ph) chromosome-positive chronic myelogenous leukemia (CML) who was treated with alpha-interferon (alpha-IFN) is reported. After the treatment, the number of Ph+ bone marrow (BM) cells decreased gradually and the intensity of the rearranged major breakpoint cluster region (M-BCR) gene became faint; however, a lymphoblastic crisis developed about 1 year later. At the time of the blast crisis, the rearranged M-BCR band was detected, indicating that the blast crisis clone was derived from CML cells. The patient was treated with a combination of vincristine, prednisolone, daunorubicin, and L-asparaginase, and a hematologic remission was obtained. During the remission status, no rearranged M-BCR fragment was detected by conventional Southern analysis. Thus, the hematologic and genetic alteration in this case appeared to be identical to Ph+ acute leukemia with M-BCR rearrangement. The current case therefore indicates that alpha-IFN can reduce the proportion of Ph+ cells, but is unable to prevent blast crisis. Furthermore, the quantitative reduction of the cell population with a Ph chromosome may have some effects in modifying the genetic manifestations and clinical features of Ph+ CML, e.g., the delay in the appearance of the blast crisis.

Antigens, CD↗

Double 20q- anomaly in myelodysplastic syndrome.

Two patients with myelodysplastic syndrome (MDS) whose bone marrow (BM) cells contained duplicate 20q- chromosomes are reported. No particular differences between the hematologic findings of four patients with single 20q- and the two patients with double 20q- chromosomes were noted. No differences in breakpoints on the 20q- chromosome were noted in these six patients, and the breakpoint was identified as 20q11. The presence of double 20q- chromosomes in MDS patients suggests, however, that the deleted chromosome has oncogenic activity.

Aged↗

Laminar specificity of extrinsic cortical connections studied in coculture preparations.

The formation of specific neural connections in the cerebral cortex was studied using organotypic coculture preparations composed of subcortical and cortical regions. Morphological and electrophysiological analysis indicated that several cortical efferent and afferent connections, such as the corticothalamic, thalamocortical, corticocortical, and corticotectal connections, were established in the cocultures with essentially the same laminar specificity as that found in the adult cerebral cortex, but without specificity of sensory modality. This suggests the existence of a cell-cell recognition system between cortical or subcortical neurons and their final targets. This interaction produces lamina-specific connections, but is probably insufficient for the formation of the modality-specific connections.

Afferent Pathways↗

Hlf, a novel hepatic bZIP protein, shows altered DNA-binding properties following fusion to E2A in t(17;19) acute lymphoblastic leukemia.

Oncogenic conversion of transcription factors by chromosomal translocations is implicated in leukemogenesis. We report that the t(17;19) in acute lymphoblastic leukemia produces a chimeric transcription factor consisting of the amino-terminal portion of HLH proteins E12/E47 (products of the E2A gene) fused to the basic DNA-binding and leucine zipper dimerization motifs of a novel hepatic protein called hepatic leukemia factor (Hlf). Hlf, which is not normally transcribed in lymphoid cells, belongs to the recently described PAR subfamily of basic leucine zipper (bZIP) proteins, which also includes Dbp and Tef/Vbp. Wild-type Hlf is able to bind DNA specifically as a homodimer or as a heterodimer with other PAR factors. Structural alterations of the E2a-Hlf fusion protein markedly impair its ability to bind DNA as a homodimer compared with wild-type Hlf. However, E2a-Hlf can bind DNA as a heterodimer with other PAR proteins, suggesting a novel mechanism for leukemogenic conversion of a bZIP transcription factor.

Amino Acid Sequence↗

Hilar and mediastinal lymphadenopathy with hypersensitivity pneumonitis induced by penicillin.

A 54-year-old Japanese man demonstrated a sultamicillin-induced hilar and mediastinal lymphadenopathy with hypersensitivity pneumonitis. A positive lymphocyte stimulation test for sultamicillin and a decreased CD4/CD8 ratio of lymphocytes in BAL fluid suggested that an alteration in cell-mediated mechanisms was responsible for the patient's symptoms.

Alveolitis, Extrinsic Allergic↗

Leukemic phase of intermediate non-Hodgkin's lymphoma with cells showing different matured stages in invaded various organs.

A 56-year-old male was admitted to our hospital with lymphocytosis (16.4 x 10(9)/l; 79% lymphocytes including 50% small lymphocytes), generalized lymphadenopathy, massive splenomegaly, and heavily infiltrated bone marrow. Immunophenotype analysis of the neoplastic cells in the bone marrow revealed that they were B cells (CD20 + CD19 + Ia1 + sIgM+) positive for CD10. By contrast, the cells in the lymph node were CD20 + CD19 + Ia1 + sIgM+ but negative for CD10. The patient was tentatively diagnosed as having lymphosarcoma cell lymphoma, however, the final diagnosis was leukemic phase of intermediate lymphocytic lymphoma. We concluded that CD10+ neoplastic cells in the bone marrow and peripheral blood had differentiated to CD10- cells.

Antigens, Differentiation↗

[Thrombotic thrombocytopenic purpura achieving complete remission by slow infusion of vincristine].

A case of thrombotic thrombocytopenic purpura (TTP) which was successfully treated by slow infusion of vincristine (VCR) is reported. A 40-year-old female was admitted to our hospital because of sudden onset of genital bleeding. Her blood cell count showed severe anemia and thrombocytopenia. Biochemistry disclosed high titers of serum LDH. Based upon these findings, the patient was initially diagnosed as having Evans syndrome and was treated with steroid-pulse therapy and high-dose immunoglobulin. However, no response was obtained. A diagnosis of TTP was established when mental disturbance and renal dysfunction developed later. Aspirin and plasmapheresis relieved the mental disturbance and decreased serum LDH level, but anemia and thrombocytopenia were not corrected. Slow infusion therapy of 1 to 2 mg VCR was performed for 4 to 8 hours once a week, which dramatically improved the hematological abnormalities and controlled the disease. In conclusion, slow infusion of VCR may indicated, if initial standard therapies such as PE would fail.

Adult↗

[Clinical evaluation of sulbactam/cefoperazone for severe infections associated with hematological disorders].

The combination therapy of sulbactam/cefoperazone (SBT/CPZ) and piperacillin (PIPC) was evaluated in 49 patients with severe infections associated with hematological disorders. Clinical responses in 43 evaluable patients out of the 49 patients were excellent in 12, good in 18, thus, overall efficacy rate was 69.8% (excellent plus good). Efficacy rates of this combination therapy were 60% (3/5) for sepsis, 75% (21/28) for suspected sepsis, and 50% (4/8) for pneumonia. The efficacy rate was 71.4% (10/14) in patients with neutrophil counts less than 200/microliters; this combination therapy was highly effective even in the neutropenic patients. Transient increases in hepatic function test values were observed in 2 patients, but no other side effects were observed during the combination therapy. From these observations it appears that the combination therapy of SBT/CPZ and PIPC is a very useful empiric therapy for severe infections associated with hematological diseases.

Adolescent↗

[Pulmonary blood flow measurement by acetylene rebreathing method in subjects without respiratory function disturbance].

Simultaneous measurement of pulmonary blood flow by the acetylene rebreathing method and cardiac output by the thermodilution method was performed in subjects without respiratory function disturbance during right heart catheterization. After the measurement of cardiac output, the subjects rebreathing a gas mixture containing acetylene and argon from the end tidal level. The inspiratory and expiratory gases were measured by a mass-spectrometer. Results were analyzed by a lung model consisting of two compartments (rebreathing bag compartment and lung compartment), while taking into account the volume reduction due to O2 and CO2 exchange and the fluctuation of end tidal gas concentration until equilibrium between the bag and the lung. The correlation coefficient between these two methods was 0.944, which was statistically significant. The regression line was near the line of identity. The measurement of pulmonary blood flow by the acetylene rebreathing method was applicable in cases without lung function disturbance.

Acetylene↗

[Immunogenotypes and surface marker analysis in Ph1 positive chronic myelogenous leukemia in the blastic crisis].

Immunophenotypic and immunogenotypic changes in 23 patients with Ph positive chronic myelogenous leukemia in blast crisis were determined using a panel of monoclonal antibodies and gene probes. According to the immunophenotypes, 9 patients were considered to be in lymphoid blast crisis, including 7 patients with lymphoblastic crisis and 2 patients with lymphoid/myeloid mixed blast crisis. Leukemia cells from the remaining 14 patients showed myeloid phenotypes and 10 of these had platelet-associated antigens. Rearrangement of the immunoglobulin (Ig) gene was observed in all the 9 patients with lymphoid blast crisis, and Ig gene rearrangement was associated with the expression of CD19 antigen. Two patients with myeloid blast crisis showed rearrangements of T-cell-receptor gene, but, dissociation between phenotypes and genotypes was not frequently observed in patients with blast crisis.

Antigens, CD↗

[A case of pulmonary eosinophilic granuloma with three-day fever].

A 45-year-old man was admitted to our hospital with chief complaint of fever. The chest X-ray examination showed 2-3 mm fine nodular shadows throughout the entire lung fields. Eosinophilia was present in the peripheral blood. Spike-like high fever (39 degrees C) appeared every 48 hours. All bacteriologic cultures from blood, bone marrow aspirate, sputum, gastric juice, and bronchoalveolar lavage fluid were negative. Furthermore, the antibody titer of malaria was negative. No antibiotics were effective in this case. Histological examination of the transbronchial lung biopsy showed non-specific inflammation, but the open lung biopsy specimen showed scattering of tiny granulomatous lesions. These granulomas were composed of histiocytes with indented nuclei, fibroblasts, varying amounts of collagen fibers, and eosinophils. The histiocytes were positive for S-100 protein staining and identified as Langerhans' cells. Therefore, this patient was diagnosed as having pulmonary eosinophilic granuloma. Two months later, the abnormal shadows on the chest X-ray and high fever spontaneously resolved without steroid therapy. This case was considered to be unique with respect to the peripheral blood eosinophilia, the three-day fever, and spontaneous improvement, compared with the former reported case.

Eosinophilic Granuloma↗

Immunogenotypes and clonal culture analysis in B-precursor acute lymphoblastic leukemia.

Immunogenotypic changes in 32 patients with B-precursor acute lymphoblastic leukemia (ALL), including three patients with t(4;11) and 13 with t(9;22), were determined using immunoglobulin heavy (IgH) chain gene probe and T-cell receptor beta, gamma and delta chain gene probes. Clonogenic assay was performed in 12 of the 32 patients. In this study, four patients had a germline configuration of the IgH chain gene, showing a dissociation between phenotypic and genotypic expression; three patients had Philadelphia-positive (Ph+) ALL. The immunogenotypic manifestation in Ph+ ALL does not depend on whether the leukemia cells had rearrangement within the major breakpoint cluster region (major-BCR) DNA sequence or the leukemia cells had myeloid-associated antigens. Colony assay using various recombinant cytokines demonstrated that the leukemia cells from four of 12 patients formed colonies in response to myelopoietic stimulants; three of the four patients were major-BCR-rearranged Ph+ ALL. Notably, cells from one patient with Ph+ ALL formed colonies on the addition of granulocytic colony-stimulating factor. This indicates not only the biological heterogeneity of ALL cells but also that some of the characteristics of the cells are related to specific chromosome changes.

Adult↗

[Efficacy of leukocyte-depleted platelet concentrates for prevention of HLA-alloimmunization in patients with frequent platelet transfusions: a prospective multi-institutional study using a polyester platelet filter].

A prospective multi-institutional study was conducted to assess the efficacy of leukocyte-depleted platelet concentrates, prepared by a method using a newly developed polyester filter, in the prevention of HLA-alloimmunization in patients with hematological disorders. Patients who were expected frequent platelet transfusions, were assigned into two groups, receiving either standard platelet concentrates (control group) or leukocyte-depleted platelet concentrates prepared through a polyester platelet filter, Sepacell-PL (filtered group). All patients received leukocyte-depleted red cell products. Of III patients enrolled, 72 were evaluable, 23 in the control and 49 in the filtered group. Both groups were comparable according to age, sex ratio, underlying disorders, previous exposure to alloantigens by transfusion and/or pregnancy. There was no statistically significant difference in the number and duration of transfusion in the two groups. There were significant differences in HLA-alloimmunization rate (9 cases out of 23, 39% in the control group versus 4 cases out of 49, 8% in the filtered group; p less than 0.01) and refractoriness to platelet transfusion from random donors (6 cases out of 23, 26% in the control group versus 2 cases out of 49, 4% in the filtered group; p less than 0.05). These results indicated that leukocyte-depleted platelet concentrates prepared through the polyester platelet filter are beneficial to reduce HLA-alloimmunization in patients with frequent platelet transfusions.

Adolescent↗

Biological activities of tetrapeptide AcSDKP on hemopoietic cell binding to the stromal cell in vitro.

The biological activity of the tetrapeptide acetyl-N-Ser-Asp-Lys-Pro (AcSDKP) on hemopoietic cell binding to the stromal cells was studied by using a rosette formation technique that quantitatively represents the specific hemopoietic cell binding to the stroma. Marrow hemopoietic cell binding to the stroma was enhanced by AcSDKP. This enhancement was completely neutralized by addition of anti-AcSDKP polyclonal antibody. Furthermore, preincubation of stromal cells with AcSDKP increased hemopoietic cell binding to the stroma, whereas preincubation of hemopoietic cells with AcSDKP showed no increment of the binding. These findings suggest that AcSDKP enhanced hemopoietic cell binding through the activation of stromal cells.

Amino Acid Sequence↗

[Multicenter clinical evaluation of red cell concentrates stored up to 6 weeks in MAP, a new additive solution].

The clinical safety and efficacy of transfusion of red cell concentrates stored in MAP solution (MAP-CRC) containing mannitol, adenine, glucose, phosphate and citrate, into 39 anemic patients were evaluated. In 23 patients, infusion of MAP-CRC was alternated with infusion of ordinary CRC as a control. The MAP-CRC and CRC used in this study were stored at 4 degrees C for an average of 38.2 +/- 2.6 days (n = 52) and 18.1 +/- 2.2 days (n = 26), respectively. Red cell recovery was 77.5% for MAP-CRC and 82.5% for CRC, based on calculation of the increase in hemoglobin level one day after transfusion. There were no differences between patients transfused with MAP-CRC and those transfused with CRC in clinical findings or biochemical data. No major side-effects other than pyrexia associated with the underlying infections were seen in patients transfused with MAP-CRC. MAP-CRC stored up to 42 days is apparently as safe and effective as stored CRC. This new additive solution may therefore be useful for the future expansion of the indications for autologous blood transfusion by facilitating the collection and storage of more blood in the liquid state for a longer period, and may also be useful in obtaining more plasma from whole blood as source plasma.

Adenine↗