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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
1997-10-8
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pubmed:abstractText |
We have studied the intrinsic radiosensitivity, repair of potentially lethal damage (PLD) and the repair rate of radiation-induced DNA double-strand breaks (DSB) in 11 non-transformed human fibroblast cell lines, four of which were homozygous for the A-T mutation and two that were heterozygous (A-TH). All the experiments were done on cells in plateau phase of growth (97-99% of cells in G0/G1). With a dose of 30 Gy delivered at 4 degrees C, the A-T cell lines had faster repair rates of up to 6 h, after which the repair curve crossed that of the control so that the residual damage at 24 h was higher in the A-T cells. Irradiation at 37 degrees C at low dose rate 1 cGy.min-1) produced even more marked differences between the A-T cells and controls: the residual DSB level was always higher in A-T cells than controls at doses of 5-40 Gy, due to defective repair of a small fraction of DSB in A-T cells. The two protocols showed DSB repair rates for the A-TH cell lines that were intermediate between those of the A-T and control cells. There was a quantitative relationship between the residual DSB after irradiation at 37 degrees C and the intrinsic radiosensitivity, and with the extent of PLD repair. There were very few apoptotic cells in the non-transformed control and A-T cell line, both before and after irradiation. In combination, these result support the contention that the defective repair of DSB is a mechanism of the hypersensitivity linked to the A-T mutation.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Sep
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pubmed:issn |
0955-3002
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
72
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
271-83
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:9298107-Ataxia Telangiectasia,
pubmed-meshheading:9298107-Cell Line,
pubmed-meshheading:9298107-DNA,
pubmed-meshheading:9298107-DNA Damage,
pubmed-meshheading:9298107-Dose-Response Relationship, Radiation,
pubmed-meshheading:9298107-Fibroblasts,
pubmed-meshheading:9298107-Humans,
pubmed-meshheading:9298107-Kinetics,
pubmed-meshheading:9298107-Radiation Tolerance,
pubmed-meshheading:9298107-Temperature
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pubmed:year |
1997
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pubmed:articleTitle |
Hypersensitivity of ataxia telangiectasia fibroblasts to ionizing radiation is associated with a repair deficiency of DNA double-strand breaks.
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pubmed:affiliation |
Laboratoire de Radiobiologie, Institut Gustave-Roussy, Villejuif, France.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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