title: Biostimulative effects of Nd:YAG Q-switch dye on normal human fibroblast cultures: study of a new chemosensitizing agent for the Nd:YAG laser.
abstract: Kodak Q-switch II is a new chemical with an absorption maxima at 1,051 nm, designed to be used as an Nd:YAG dye laser. The potential for this dye as a new chemosensitizing agent in the treatment of connective tissue diseases and wound healing with low energy Nd:YAG laser was examined. Two normal fibroblast cell lines were tested for sensitivity to various levels of this dye in vitro. These cells were exposed to Q-switch II dye at concentrations of 0.01, 0.1, 1, 10, 50, and 100 micrograms/ml for 1 and 24 hours. Cell viability was assessed by the trypan blue exclusion test. Cell duplication and DNA synthesis were measured by the incorporation of [3H]-thymidine at 6 and 24 hours postexposure to Q-switch II dye. At concentrations up to 10 micrograms/ml, both cell lines tested showed no changes in cell viability. However, at concentrations equal or higher than 50 micrograms/ml, more than 40% of the fibroblasts incorporated trypan blue after 24 hours of exposure to this dye, indicating significant cell destruction. The results indicate that Q-switch II dye is nontoxic to normal human fibroblast cultures and showed significant biostimulative effects on cell duplication at concentrations equal to or lower than 10 micrograms/ml. Further studies will be required to determine the usefulness of Q-switch II dye as a new photochemosensitizing agent for potential biostimulation of wound healing and/or treatment of connective tissue diseases with the Nd:YAG laser (near infrared, 1,060 nm) at "nonthermal" levels of energies.
authors: Division of Head and Neck Surgery (Otolaryngology), UCLA School of Medicine 90024.
authors: D J
authors: DJ
authors: Castro
authors: R E
authors: RE
authors: Saxton
authors: H R
authors: HR
authors: Fetterman
authors: D J
authors: DJ
authors: Castro
authors: P H
authors: PH
authors: Ward
mesh_terms: D001578:Benzopyrans / Q000494:pharmacology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D055598:Chemical Phenomena; D002621:Chemistry; D004247:DNA / Q000096:biosynthesis; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D053685:Laser Therapy; D009994:Osmolar Concentration; D011838:Radiation-Sensitizing Agents / Q000494:pharmacology*; D012867:Skin / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors
chemical_list: D001578:Benzopyrans; D011838:Radiation-Sensitizing Agents; C054228:Q-switch II dye; D004247:DNA