Τίτλος:
Biodosimetry for high-dose exposures based on dicentric analysis in lymphocytes released from the g2-block by caffeine
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
High-dose assessments using the conventional dicentric assay are essentially restricted to doses up to 5 Gy and only to lymphocytes that succeed to proceed to first post-exposure mitosis. Since G2-checkpoint activation facilitates DNA damage recognition and arrest of damaged cells, caffeine is used to release G2-blocked lymphocytes overcoming the mitotic index and dicentric yield saturation problems, enabling thus dicentric analysis even at high-dose exposures. Using the fluorescence in situ hybridization technique with telomere and centromere peptide nucleic acid probes, the released lymphocytes, identified as metaphases with decondensed chromosomes following 1.5 h caffeine treatment, show increased yield of dicentrics compared to that obtained in lymphocytes that reach metaphase without G2-checkpoint abrogation by caffeine. Here, a 3-h caffeine/ colcemid co-treatment before harvesting at 55 h post-exposure is used so that the dicentric analysis using Giemsa staining is based predominantly on lymphocytes released from the G2-block, increasing thus dicentric yield and enabling construction of a dose-response calibration curve with improved precision of high-dose estimates. © The Author 2016.
Συγγραφείς:
Karachristou, I.
Karakosta, M.
Pantelias, A.
Hatzi, V.
Pantelias, G.
Thanassoulas, A.
Karaiskos, P.
Dimitriou, P.
Terzoudi, G.I.
Περιοδικό:
Radiation Protection Dosimetry
Εκδότης:
Oxford University Press
Λέξεις-κλειδιά:
caffeine, bioassay; cell culture; chromosome aberration; chromosome analysis; drug effects; G2 phase cell cycle checkpoint; genetics; human; lymphocyte; procedures; radiation dose; radiation response; radiometry; reproducibility; sensitivity and specificity, Biological Assay; Caffeine; Cells, Cultured; Chromosome Aberrations; Cytogenetic Analysis; Dose-Response Relationship, Radiation; G2 Phase Cell Cycle Checkpoints; Humans; Lymphocytes; Radiation Dosage; Radiometry; Reproducibility of Results; Sensitivity and Specificity
