The radiation survival curves for the proliferative capacity of mammalian cells, both in vitro (1, 2) and in vivo (3, 4), are sigmoidal, suggesting that loss of proliferative capacity involves an accumulation of radiation damage. For mammalian cells in culture, Elkind and co-workers (5, 6) have demonstrated that accumulated sublethal damage may be rapidly repaired in surviving cells, by means o...

background: exposure to ionizing radiation is known to induce oxidative stress followed by damage to critical biomolecules like lipids, proteins and dna through radiolysis of cellular water. since radiation has been widely used as an important tool in therapy of cancer, the detailed investigation regarding the dna damage and repair kinetics would help to predict the radiation sensitivity of cel...

The phthalocyanine dyes are attractive sensitizers for photodynamic therapy of cancer. The light fluence response curves for photocytotoxicity of zinc tetrahydroxyphthalocyanine were constructed using the colony-forming ability of Chinese hamster cells as an end-point. The survival curve of cells photosensitized to white light by this dye has a pronounced shoulder followed by an exponential dec...

objective(s): coronary artery disease (cad) is the leading cause of death in both male and female worldwide. the main cause of cad is the atherosclerosis of coronary arteries, which is, mostly caused by genetic alteration. 50% of such cases occur in mitotic cells where single-strand breaks occur spontaneously or due to ionizing radiation. x-ray repair cross-complementing protein 1 (xrcc1) as a ...

Polyamines are involved in many cellular processes, including DNA structure and function. Since DNA, or some DNA-containing structure, is known to be the target for cell killing induced by ionizing radiation and a number of chemotherapeutic agents, we investigated the effects of polyamine depletion on cytotoxic responses of Chinese hamster cells to X-irradiation. Colony forming ability after si...

Background: Exposure to ionizing radiation is known to induce oxidative stress followed by damage to critical biomolecules like lipids, proteins and DNA through radiolysis of cellular water. Since radiation has been widely used as an important tool in therapy of cancer, the detailed investigation regarding the DNA damage and repair kinetics would help to predict the radiation sensitivity of cel...

Polyamines are involved in many cellular processes, including DNA structure and function. Since DNA, or some DNA-containing structure, is known to be the target for cell killing induced by ionizing radiation and a number of chemotherapeutic agents, we investigated the effects of polyamine depletion on cytotoxic responses of Chinese hamster cells to X-irradiation. Colony forming ability after si...

Deinococcus radiodurans is extremely resistant to various genotoxic conditions and chemicals. In this study, we characterized the effect of a sublethal concentration (100 microM) of cadmium (Cd) on D. radiodurans using a whole-genome DNA microarray. Time-course global gene expression profiling showed that 1,505 genes out of 3,116 total ORFs were differentially expressed more than 2-fold in resp...

Low linear energy transfer (LET) ionizing radiation (IR) is an important form of therapy for acute leukemias administered externally or as radioimmunotherapy. IR is also a potential source of DNA damage. High LET IR produces structurally different forms of DNA damage and has emerged as potential treatment of metastatic and hematopoietic malignancies. Therefore, understanding mechanisms of resis...

An analysis of mammalian cell radiation ± dose surIn studies concerning mechanisms that determine vival curves, based on the linear ± quadratic formalism, is shown radiosensitivities of mammalian cells, three di å erent to yield insights in the various components of damage that approaches can be distinguished which complement contribute to cell reproductive death . R B E ± LET relationships of ...