Subject(s)
Corneal Dystrophies, Hereditary/diagnosis , Descemet Membrane/pathology , Endothelium, Corneal/pathology , Iris Diseases/diagnosis , Adult , Corneal Dystrophies, Hereditary/surgery , Corneal Edema/diagnosis , Corneal Edema/surgery , Female , Humans , Iris Diseases/surgery , Keratoplasty, PenetratingABSTRACT
PURPOSE: To develop a rabbit model of reproducible corneal haze after excimer laser keratectomy and to characterize expression of transforming growth factor beta (TGFbeta) and basic fibroblast growth factor (bFGF) in rabbit corneas during haze formation. METHODS: Seven rabbits underwent a 100 microm deep phototherapeutic keratectomy (PTK) in one eye and a 15-microm shallow PTK in the contralateral eye. Corneal haze was compared at 1-20 weeks after surgery. Subsequently, 16 rabbits underwent 100-microm PTK in one eye and 15-microm PTK in the contralateral eye. Four rabbits were killed at 1, 2, 3, and 4 weeks, respectively, after surgery. Immunohistochemistry was performed on the corneas to localize the expression of TGFbeta and bFGF. Control subjects were rabbits that underwent either epithelial debridement alone or no surgery. RESULTS: A 100-microm PTK resulted in significantly more corneal haze than a 15-microm PTK at every postoperative examination (p < 0.05). Both TGFbeta and bFGF were expressed in the scars at 1-4 weeks after deep and shallow excimer ablations. bFGF was expressed in the keratocytes of both treated and control corneas. Minimal TGFbeta was detected in the keratocytes of the control corneas, whereas prominent TGFbeta expression was noted in the keratocyte-like cells adjacent to the postkeratectomy scars. CONCLUSIONS: The 100-microm PTK ablation resulted in significantly more corneal scarring than the 15-microm PTK ablation. Even though there was no immunohistochemical difference in the pattern of TGFbeta and bFGF expression after deep and shallow ablations, there was an association between the expression of the growth factors and corneal scarring after excimer laser keratectomy.
Subject(s)
Cornea/metabolism , Corneal Opacity/metabolism , Fibroblast Growth Factor 2/metabolism , Photorefractive Keratectomy/adverse effects , Transforming Growth Factor beta/metabolism , Wound Healing , Animals , Cornea/pathology , Cornea/surgery , Corneal Opacity/etiology , Corneal Opacity/pathology , Immunoenzyme Techniques , Lasers, Excimer , Male , Rabbits , Time FactorsABSTRACT
DNA probes directly conjugated to horseradish peroxidase have been used successfully to detect human papillomavirus (HPV) types 6/11, 16, and 18 in formalin-fixed, paraffin-embedded tissue sections. By using silver enhancement of a heavy metal-modified diaminobenzidine precipitate, the sensitivity of human papillomavirus detection was significantly increased without compromising specificity. In studies comparing the specificity of the horseradish peroxidase-labeled probe/silver enhancement system to that of a biotinylated-DNA probe/streptavidin-alkaline phosphatase system, the former was found to be superior.
