title: Dynamic aspects of rhodamine dye photosensitization in vitro with an argon-ion laser.
abstract: Phototoxicity in cultured human bladder carcinoma cells treated by 514.5-nm argon-ion laser irradiation plus rhodamine-123 (R123) or tetrabromo-R123 (TBR) was assessed counting total cell number and percent viability at 1, 24, 48, 72, and 96 h after irradiation. TBR was markedly more efficient than R123 at causing both reversible and persistent phototoxic cytostasis. Furthermore, TBR photosensitization caused net cytocidal effects at 0.5 J/cm2, which were not seen with R123 photosensitization at up to 40 J/cm2. The reduced phototoxic efficiency of R123 as compared to TBR appears, in part, to reflect the presence of a fraction of cells refractory to R123 photosensitization.
authors.affiliation: Wellman Laboratories of Photomedicine, Department of Dermatology, Harvard Medical School, Massachusetts General Hospital, Boston 02114.
authors.forename: C R
authors.initials: CR
authors.lastname: Shea
authors.forename: N
authors.initials: N
authors.lastname: Chen
authors.forename: T
authors.initials: T
authors.lastname: Hasan
mesh_terms: D000970:Antineoplastic Agents; D002295:Carcinoma, Transitional Cell; D005456:Fluorescent Dyes; D006801:Humans; D066298:In Vitro Techniques; D007834:Lasers; D010778:Photochemotherapy; D020112:Rhodamine 123; D012235:Rhodamines; D014407:Tumor Cells, Cultured; D001749:Urinary Bladder Neoplasms; D014966:Xanthenes
chemical_list: D000970:Antineoplastic Agents; D005456:Fluorescent Dyes; D012235:Rhodamines; D014966:Xanthenes; D020112:Rhodamine 123