Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-10-8
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.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0955-3002
pubmed:author
pubmed:issnType
Print
pubmed:volume
72
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
271-83
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Hypersensitivity of ataxia telangiectasia fibroblasts to ionizing radiation is associated with a repair deficiency of DNA double-strand breaks.
pubmed:affiliation
Laboratoire de Radiobiologie, Institut Gustave-Roussy, Villejuif, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't