Excimer laser treatment during therapeutic photo&active keratectomy (PFtK) vaporims human corneal tissue, producing irritant fumes which can be collected on 0.45 micron sterile Teflon filters (Miiart Sartorius, Germany). Filters from PRK performed by a 194nm argon-fluoride excimer laser (Aesculap Meditec MELBO, Italy) on 80-100 microns of comeal stroma, were examined by warming electron microscopy, revealing dense particulate deposits on Teflon fibers. PFtK Glters were then washed by gentle shaking in normal sterile saline solution for 20 minutes. The fluid obtained was assayed for oxygen radical production by fluorometric analysis of DNA unwinding (FADU), spectrophotometric tests (ST), electron paramagnetic resonance (EPR), Western blot and dot-blot hybridization. The results show a significant superoxide production, detected by FADU, ST and EPR in fluids recovered from PRK filters in comparison to controls. Analyses by Western blot and dot-blot hybridization suggest the presence in PFLK filters of active xanthme tidase, a superoxide-producing enzyme system.
Production of oxygen radicals by humans corneal stroma vaporized during excimer laser photorefractive keratectomy.
CHICCA, Milvia;BORGHI, Monica;GOLFETTO, Gualtiero;LEIS, Marilena;VERONESI, Carlo;SEBASTIANI, Adolfo;PINAMONTI, Silvano
2001
Abstract
Excimer laser treatment during therapeutic photo&active keratectomy (PFtK) vaporims human corneal tissue, producing irritant fumes which can be collected on 0.45 micron sterile Teflon filters (Miiart Sartorius, Germany). Filters from PRK performed by a 194nm argon-fluoride excimer laser (Aesculap Meditec MELBO, Italy) on 80-100 microns of comeal stroma, were examined by warming electron microscopy, revealing dense particulate deposits on Teflon fibers. PFtK Glters were then washed by gentle shaking in normal sterile saline solution for 20 minutes. The fluid obtained was assayed for oxygen radical production by fluorometric analysis of DNA unwinding (FADU), spectrophotometric tests (ST), electron paramagnetic resonance (EPR), Western blot and dot-blot hybridization. The results show a significant superoxide production, detected by FADU, ST and EPR in fluids recovered from PRK filters in comparison to controls. Analyses by Western blot and dot-blot hybridization suggest the presence in PFLK filters of active xanthme tidase, a superoxide-producing enzyme system.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
