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Biomedical subjects

S Aoyama

Publications and source records attributed to S Aoyama.

At least 55 records · Page 3Linked to original sources
PubMed1987

Analysis of the chromosomal abnormalities of a woodchuck hepatocellular carcinoma-derived cell line (WH257GE10).

The normal woodchuck karyotype was determined by the G-banding technique, and the chromosomal abnormalities of a woodchuck hepatocellular carcinoma-derived cell line (WH257GE10) were analyzed and compared with it. The normal woodchuck karyotype was 38,XY in a male, and 38,XX in a female. Autosomes were classified into 2 groups (A and B). Group A consisted of 13 pairs (1-13) of metacentric or sub-metacentric chromosomes, and group B consisted of 5 pairs (14-18) of telocentric or sub-telocentric ones. The X chromosome was sub-metacentric, and the Y chromosome was telocentric. In WH257GE10, the modal number was 36. Deletion of one of the chromosome 5 pair, of the chromosome 13 pair, and of the Y chromosome was observed. Two marker chromosomes (M1 and M2) were found. These markers showed the same G-banded patterns except for a small chromosome fragment at the distal part of the long arm of M1. The chromosome aberrations were very stable through successive passages in vitro. These findings suggest that the chromosomal abnormalities found in WH257GE10 might be associated with the pathogenesis of woodchuck hepatocellular carcinoma.

Animals↗
PubMed1987

[Therapeutic effects of a combination of intermediate-dose cytosine arabinoside, adriamycin and vincristine in relapsed acute leukemia].

Eleven cases of acute leukemia, 8 relapsed and 3 refractory to a conventional induction chemotherapy, were treated with a combination of intermediate-dose cytosine arabinoside (ara-C), adriamycin (ADM) and vincristine (VCR). They consisted of 9 ANLL and 2 ALL. The therapeutic regimen consisted of 1-hour infusion of ara-C of a dose of 500 mg/m2 every 12 hours for 6 days from days 3 to 8, ADM, 40 mg/m2, on day 1 and VCR, 1.4 mg/m2, on day 2. Among 11 cases in which an evaluation was possible, 7 obtained complete remission (CR). The CR rate was 77.8% in the 9 cases of ANLL. The toxicity of this regimen included the following: conjunctivitis in 4 of 11 cases (36%), nausea and vomiting in 9 of 11 cases (91%) and hair loss in all cases, although no toxicities of the central nervous system of liver were observed. The mean level of serum concentration of ara-C was above 10 microM at 15, 30 and 60 minutes after the initiation of infusion. The therapeutic effect of this regimen consisting of intermediate-dose ara-C is expected to be useful not only in induction of refractory and relapsed acute leukemia, but also in the postremission therapy of CR cases.

Acute Disease↗
PubMed1986

Immunohistochemical characterization of inflammatory infiltrates at the site of bile duct injury in primary biliary cirrhosis.

Surgically obtained liver specimens from four patients with primary biliary cirrhosis (PBC), Stages I-II, were studied immunohistochemically using a broad panel of monoclonal antibodies. At the site of bile-duct injury (CNSDC), the inflammatory cells were recognized to be Coulter T-11+ (directed against all T-cells) and OKT-8+ (directed against cytotoxic/suppressor: C/S T-cells) cells. The MHC-class I antigen (i.e. HLA-A, B, C) was expressed weakly in the cytoplasm of the minority of damaged bile-duct epithelial cells, and the MHC-class II antigen (i.e. HLA-DR) was not expressed. Thus, OKT-8+ cells may play an important role in the immunologically mediated destruction of ductular epithelium in PBC. Strong MHC-antigen expression and OKT-8+ cell infiltration in destructive bile-duct lesions were not simultaneously observed. In the portal lymphocyte-rich areas, OKT-4+ (directed against helper/inducer: H/I T-cells) predominated over OKT-8+ cells. B-lymphocytes were present predominantly in the peripheral zones of the lymphoid aggregates. The distribution of helper/inducer T-cells and B-lymphocytes indicates that they may play a role in the induction of immunoglobulin in the lymphocyte-rich areas. The inflammatory mononuclear cells within the granuloma observed in one patient were Coulter T-11+, OKT-8+ and Leu-3a+3b+ (directed against helper/inducer T-cells) cells.

Adult↗
PubMed1986

Stable integration of woodchuck hepatitis virus DNA in transplanted tumors and established tissue culture cells derived from a woodchuck primary hepatocellular carcinoma.

The fate of integrated woodchuck hepatitis viral (WHV) DNA was systematically investigated in DNA samples from primary hepatocellular carcinoma (HCC) of woodchucks, solid tumors transplanted in athymic mice derived from a primary HCC of woodchuck, and an established cell line of tissue culture originating from the transplanted tumor. In four of five woodchuck primary HCCs, WHV DNA integration was demonstrated in addition to various amounts of extrachromosomal replicative intermediate WHV DNA. The integration pattern of the primary HCCs does not indicate a common integration site on the host chromosome. The integration pattern in the established cells is identical to that in the transplanted tumor and similar but slightly different from that of the primary HCC. No extrachromosomal or replicative intermediates of WHV DNA were detected in the transplanted tumors or in the established cells of tissue culture. There are three integration sites on the chromosomes of the established cells. Results of Southern hybridization and restriction maps of cloned fragments suggest that all of these integrated WHV DNA sequences are not a complete genome but a part of the genome. A small portion corresponding to the cohesive region of the genome was not detected in all of these integrated WHV DNA. A positive role of WHV DNA integration on the generation of HCC is strongly suggested by the high incidence of WHV DNA integration in woodchuck primary HCCs and the stable maintenance of a certain mode of WHV DNA integration in the hepatoma-derived cell populations during passages of transplantation or serial growth of tissue culture.

Animals↗
PubMed1986

[Low-dose 4N-behenoyl-1-beta-D-arabinofuranosylcytosine (BHAC) in the treatment of atypical leukemia].

Four cases of hypoplastic leukemia, one of acute myelocytic leukemia (M2) and one of RAEB-t were treated with a low-dose 4N-behenoyl-1-beta-D-arabinofuranosylcytosine (LD-BHAC) regimen, in which 50 mg BHAC was administered daily intravenously by one-hour drip infusion for 14 days. Among the 6 cases, three (2 hypoplastic leukemia and one M2) obtained complete remission and one (hypoplastic leukemia), partial remission. Response rates were 66.6% of all cases, and 75% of cases of hypoplastic leukemia. During treatment, cytopenia was observed in all cases and a decrease in bone marrow nucleated cell counts was recognized in the aged M2 patient with remission. Although side effects of the drug on the digestive system such as anorexia and nausea were observed in some cases, they were all controllable by conventional treatments. The serum concentration of ara-C was measured in 4 cases. The peak level of serum ara-C concentration, 3.62-18.9 ng/ml (mean: 11.74 ng/ml), was observed at the time of cessation of infusion of BHAC, and an ara-C level of 2.75-4.89 ng/ml (mean: 3.54 ng/ml) was still present in the blood 6 hours after the cessation of infusion. It was concluded that LD-BHAC was useful in the clinical management of atypical leukemia and acute myelocytic leukemia in the aged.

Adult↗
PubMed1985

Monocyte chemiluminescence and macrophage precursors in the aged.

Age-related alterations in the host defense system have been vigorously investigated because of increased susceptibility to infection and neoplasms in the aged. Although monocyte-macrophages form a major part of the cellular defense against microorganisms, the majority of investigations has been limited to neutrophils and lymphocytes. The present study, designed to determine the influence of age on mononuclear phagocytes, revealed no significant decrease in the absolute number of blood monocytes, but did reveal a tendency for the chemiluminescence of blood monocytes to decrease (p less than 0.10) and a significant decrease in the numbers of macrophage precursors (p less than 0.05) in the aged (over 70 year old), in comparison with controls (under 40 years old). On the basis of these findings, functional alterations of monocyte-macrophages seem to participate in the increased susceptibility to infection in the aged.

Adult↗