Fig. 5. Survival of irradiated or non-irradiated i28 cells as measured by MTT assay of mitochondrial function (A). (B) Hoechst staining for DNA nuclei, 24 hours post irradiation. Note the fragmented/apoptotic nuclei versus the intact ones in control and laser-treated cells, respectively. (C) Apoptotic nuclei were counted and data are presented as a percentage of total nuclei. Each graph represents mean±s.e.m of three replicates in which more than 1,000 cells were individually examined.