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Biomedical subjects

K Hirashima

Publications and source records attributed to K Hirashima.

At least 145 records · Page 8Linked to original sources
PubMed1983

Chromosomal aberrations observed in 52 mouse myeloid leukemias.

Chromosomes of 52 cases of mouse myeloid leukemia were examined. There were 5 myeloblastic leukemias, 22 granulocytic leukemias, 17 myelomonocytic leukemias, and 8 monocytic leukemias. Fifty cases were radiation induced and the other 2 were nonirradiated. Each case had leukemic cells with 1 to 10 marker chromosomes. Partially deleted No. 2 chromosomes appeared in 49 cases, including 2 nonirradiated cases. These deleted No. 2 chromosomes were varied in size, and they were classified into 7 types according to morphological features. There was no type-dependent difference in histological or cytological features among the 7 types. It was found that the chromosomal segment lying between Regions 2C and 2D was commonly missing from all of the deleted No. 2 chromosomes. In addition to such No. 2 chromosomes, an anomaly in chromosome 6 was observed in 16 cases, of which 12 cases were granulocytic leukemia. The abnormalities of chromosomes 3 and 9 were next most frequent, appearing in 14 cases each. Besides such structural anomalies, numerical changes involving the Y chromosome (33 cases), chromosome 6(6 cases), and chromosome 15 (4 cases) were also found. Characteristics of the karyotypes of the mouse myeloid leukemia in comparison with other leukemias were noted. The significance of the specific segments of the chromosomes which were commonly missing or trisomic in the karyotypes of neoplasias in mice, rats and humans was discussed. It was suggested that the genesis of myeloid leukemia was greatly influenced by the genetic information on chromosome 2 in mice.

Animals↗
PubMed1982

Effects of aclacinomycin-A on murine leukemia.

Effects of aclacinomycin-A (ACM) on leukemic cells and normal hematopoietic stem cells were studied for the purpose of evaluating the usefulness of this agent as an antileukemic agent. ACM suppressed not only leukemic colony-forming unit (LCFU) in the radiation-induced murine erythroleukemia, but also normal hematopoietic stem cells (CFU-S, CFU-C) in mice. However, LCFU was the most sensitive to ACM. After the administration of ACM at a dose of 5 mg/kg. LCFU was suppressed to 0.02 of the control on day 3 and recovered within 5 days. Splenic CFU-S and CFU-C were suppressed to the nadirs on day 2 and day 1, respectively, and they recovered within 5 days. On the basis of the differences in the sensitivities to ACM and recovery patterns between LCFU and normal hematopoietic stem cells. ACM at a single dose of 5 mg/kg was administered every 3 days (total dose of 25 mg/kg) into leukemic mice, and the increase in mean lifespan obtained 113.9%. Effectiveness of ACM in the treatment of acute leukemia was discussed.

Aclarubicin↗
PubMed1982

Granulopoietic inhibitors excreted in the urine of a patient with uterine cancer and marked leukocytosis.

An inhibitor of colony stimulating factor (CSF) was found in normal human urine and in the urine of a patient with uterine cancer and leukocytosis. The amount of inhibitor excreted in the patient's urine was inversely related to the amount of CSF excreted. Since the patient's urine contained the inhibitor in large amounts, it was used for further characterization of the inhibitor. The inhibitor was separated from CSF by DEAE-cellulose column chromatography, and precipitated by ammonium sulfate and 30-80% saturation. The result of centrifugation of the inhibitor in a NaBr solution of d = 1.21 and extraction of its solution by chloroform suggested that it is not a lipoprotein. Furthermore, it was inactivated by heating at 60 degree C. Isoelectrofocusing resolved in into two peaks of pI 6.7-8.4 (pI-7 inhibitor) and pI 4.7-5.4 (pI-5 inhibitor), both of which showed an apparent molecular weight of 80,000-90,000 upon Sephadex G-100 chromatography. Dose-response relation for CSF in the presence of the inhibitor(s) showed that the action of the inhibitor(s) was not due to specific inactivation of CSF. Both pI-05 and pI-7 inhibitor fractions showed mitogenic activity to mouse spleen cells in culture, and only slightly inhibited [3H]thymidine uptake in the PHA or LPS stimulated spleen lymphocytes. The result suggests that the granulopoietic inhibitor(s) obtained above is not a non-specifically cytotoxic substance(s).

Aged↗
PubMed1982

Effects of chloramphenicol on hematopoietic inductive microenvironment.

Effects of chloramphenicol (CP) on hematopoietic inductive microenvironment (HIM) were studied using in vitro and in vivo assay systems. HIM was represented as fibroblast colonies (CFUF) in in vitro culture. CP suppressed the growth of not only granuloid committed progenitor cells (CFUC), but also CFUF in in vitro culture at the concentration of 10, 50 and 100 micrograms/ml. To analyze the function of HIM in vivo, the subcutaneous bone implantation method was used. The recovery of hematopoietic stem cells in subcutaneously implanted femora of mice, which were treated with a 500 mg/kg dose of CP daily for 6 days, was significantly decreased compared to the sham treated group. Suppressive effect of CP on HIM was shown. The important role of the derangement of HIM on the pathogenesis of CP-induced aplastic anemia was discussed.

Anemia, Aplastic↗
PubMed1981

Effects of leukemic cells on hematopoiesis in radiation-induced murine erythroleukemia.

Erythroleukemia occurred in a BCF1 mouse after X-irradiation. This leukemia was maintained by leukemic cell transplantation successively without changes in the characters of leukemia. According to leukemic cell proliferation, peripheral blood leukemic cells increased in number, and anemia and granulocytopenia developed. Following leukemic cell infiltration, granuloid-committed stem cells (CFU-C) in bone marrow decreased but those in spleen increased. Neither leukemic cells nor leukemic cell-conditioned medium inhibited CFU-C culture in vitro. Effects of leukemic cells on hematopoiesis were discussed.

Animals↗
PubMed1979

Partial deletion of chromosome No. 2 in myelocytic leukemias of irradiated C3H/He and RFM mice.

Chromosomes of mouse myelocytic leukemias that developed in 7 irradiated mice, 3 C3H/He males, 1 RFM female, and 3 RFM males were analyzed with chromosome-banding techniques. Chromosomes No. 2 were partially deleted in 6 of the 7 mice. Although the deleted No. 2 chromosomes varied in size in the 6 mice, one common characteristic was noted in all these deletions: A segment lying between a certain band in the region 2C and a band in the region 2E, including the whole region 2D, was missing. Another consistent abnormality was an addition or a loss of the Y-chromosomes in the fraction of cells in all 6 males. In addition to these consistent abnormalities, various chromosomes had structural abnormalities. The RFM female, which did not have the abnormal No. 2 chromosome, had abnormalities in chromosomes No. 3, 4, 11, 12 and 15 and in the X-chromosome. Of the 20 chromosome pairs, only such chromosomes as No. 1, 5, 8, 14, 17, and 19 and the Y-chromosome did not have the structural abnormalities. The possible role of the partial deletion of the No. 2 chromosome was considered in relation to the development of mouse myeloid leukemias.

Animals↗
PubMed1978

Enhancement of the action of colony stimulating factor (CSF) by soluble component(s) of erythrocytes in mouse bone marrow cells cultures.

Rat erythrocytes, separated from other blood cells by SE-cellulose chromatography, were lysed by exposure to hypotonic solution, dialyzed and ultracentrifuged. The supernatant contained a substance which enhanced the activity of colony stimulating factor (CSF) in soft agar cultures of granulocyte-macrophage progenitor cells (CFU-C) from normal mouse bone marrow. The growth-enhancing effect of the erythrocyte factor was observed when mouse L-cell conditioned medium was used as the CSF source and also when serum from endotoxin-treated mice or from mice undergoing graft-versus-host reaction was used as the stimulant. The erythrocyte factor effect was also detected by 3H-thymidine uptake of bone marrow cells in liquid cultures. These results suggest that the effect of the erythrocyte factor on CSF is not restricted to CSF from a specific source nor to semi-solid agar cultures.

Animals↗