PubMed Health⌕ Search

Biomedical subjects

A Kurimasa

Publications and source records attributed to A Kurimasa.

22 records · Page 2Linked to original sources
PubMed1994

A human gene that restores the DNA-repair defect in SCID mice is located on 8p11.1-->q11.1.

In order to map the gene that is responsible for the DNA-repair defect in severe combined immune deficient (SCID) mice, a mixture of microcells independently isolated from mouse A9 cells containing pSV2neo-tagged human chromosomes 5, 7, 8, 9, 11, 15, 18 or 20 were fused with SCID fibroblast cell lines SCVA2 and SCVA4, which were originally established from lung tissue of the C.B.17-scid/scid mouse by SV40 virus transfection. After irradiation with 60Co gamma-rays and selection with antibiotic G418, 12 independent clones were obtained, of which 4 contained an intact chromosome 8, 3 clones contained a deleted chromosome 8 [del(8)q22-->qter or del(8)q23--> qter] and remaining 5 had no detectable or specific human chromosome. We further independently transferred a single human chromosome 8 or 11 into the SCVA cells via microcell fusion, and examined the radiation sensitivity of the microcell hybrids. Complementation of the radiation sensitivity was correlated with the presence of human chromosome 8 in microcell hybrids, whereas no correlation was observed in clones following the transfer of human chromosome 11. Thus, the results indicate that human chromosome 8 restored high sensitivity to ionizing radiation. A number of subclones that were radiation resistant or sensitive were isolated from the microcell hybrids. The concordance of the radiation sensitivity with the presence or absence of specific DNA fragments on chromosome 8 indicates that the human gene is located on the centromeric region of chromosome 8, i.e., 8p11.1--> q11.1.

Animals↗
PubMed1993

Restoration of the cholesterol metabolism in 3T3 cell lines derived from the sphingomyelinosis mouse (spm/spm) by transfer of a human chromosome 18.

We searched for a human chromosome that would restore the cholesterol metabolism in 3T3 cell lines (SPM-3T3) derived from homozygous sphingomyelinosis mice (spm/spm). Mouse A9 cells containing a single copy of pSV2neo-tagged chromosomes 9, 11, or 18 derived from normal human fibroblasts served as donor cells for transfer of human chromosomes. Purified A9 microcells were fused with SPM-3T3 cells, and the microcell hybrids were selected in medium containing G418 antibiotics. The microcell hybrids that contained human chromosomes 9, 11, or 18 in a majority of cells were examined. The accumulation of intracellular cholesterol in the microcell hybrids containing a chromosome 18 decreased markedly, whereas in the microcell hybrids containing either chromosomes 9 or 11 it was similar to that in SPM-3T3 cells. The SPM-3T3 cells with an intact chromosome 18 were further passaged and subcloned. Clones which again accumulated intracellular cholesterol had concurrently lost the introduced chromosome 18. The abnormal accumulation was associated with a decrement in the esterification of exogenous cholesterol. These findings suggest that the gene responsible for the abnormal cholesterol metabolism in the spm/spm mice can be restored by a human chromosome 18. The gene was tentatively mapped on 18pter-->18p11.3 or 18q21.3-->qter that was lost during subcloning, thereby resulting in reaccumulation of the intracellular cholesterol.

3T3 Cells↗
PubMed1992

Proteus syndrome: report of the first Japanese case with special reference to differentiation from Klippel-Trenaunay-Weber syndrome.

This is the first report of a Japanese girl with Proteus syndrome. She presented with growth acceleration and precocious development of the left breast as well as macrodactyly, hemihypertrophy, a subcutaneous preaxillary mass, portwine stains, connective tissue nevi, and a depigmented macule. All these abnormalities were confined to the left side of her body. Although most of the manifestations fit those of Proteus syndrome, the presence of the portwine stains and hemihypertrophy also suggested Klippel-Trenaunay-Weber syndrome. The findings in our patient suggest that the most important characteristic distinguishing Proteus syndrome from Klippel-Trenaunay-Weber syndrome is the presence of functional abnormalities such as a growth spurt and precocious breast development. Proteus syndrome may be genetically different from the Klippel-Trenaunay-Weber syndrome.

Child, Preschool↗