Search

Your search keyword '"Evans, Margaret DM"' showing total 5 results
Start Over Author "Evans, Margaret DM"
5 results on '"Evans, Margaret DM"'

2. The role of MMPS and TIMPS in the feline ocular surface system during corneal epithelial wound healing

Author

Sweeney, Deborah F, University of Western Sydney, Evans, Margaret DM, CSIRO, Garrett, Qian, Brien Holden Vision Institute, Petznick, Andrea, Optometry & Vision Science, Faculty of Science, UNSW, Sweeney, Deborah F, University of Western Sydney, Evans, Margaret DM, CSIRO, Garrett, Qian, Brien Holden Vision Institute, and Petznick, Andrea, Optometry & Vision Science, Faculty of Science, UNSW

Abstract

The ocular surface system is a complex microenvironment including the cornea, conjunctiva, lacrimal gland, meibomian glands and tear film. Matrix metalloproteinases (MMPs), a family of zinc- and calcium-dependent proteinases involved in maintaining and remodelling extracellular matrix and inflammation, have been found in ocular tissues and tears. The analysis of tears has been used to identify potential biomarkers for eye diseases. Contributions of individual ocular surface components to tear proteins are not fully understood. This study investigated the expression of MMPs and tissue inhibitors of MMPs (TIMPs) (particularly MMP-9 and -2) in tears and ocular tissues following corneal epithelial wounding (debridement) at predetermined time points using a feline model. Preliminary work validated the use of eye-flush tears (collected after instillation of saline) and procedural control eyes (same treatment as wounded eyes) as controls for the tear collection study. Gelatin zymography and immunohistochemistry were used to detect MMPs and TIMPs in tears and ocular surface tissues, and data was then analysed using statistical methods. During corneal healing, expression of MMP-9 was detected in all ocular surface components with significant increase in tears, the corneal and limbal epithelium, keratocytes and conjunctival epithelium. In contrast, MMP-2 was found significantly increased only in tears and the corneal and conjunctival epithelium. Analysis of tears from wounded and procedural control eyes suggested a minimal contribution of the healing corneal epithelium to tear-derived MMP-9 and -2. Other possible contributors to increased tear MMP-9 levels included the lacrimal gland, inflammatory cells in conjunctival tissue including conjunctival-associated lymphoid tissue (CALT). Expression of MMP-1, TIMP-1 and -2 in ocular tissues in response to wounding were also investigated. MMP-1 was increased in the healing corneal epithelium, keratocytes and limbal epithelium. TIMP

Published
2010

3. Synthetic corneal inlays

Author

Sweeney, Deborah F, primary, Vannas, Antti, additional, Hughes, Timothy C, additional, Evans, Margaret Dm, additional, Mclean, Keith M, additional, Xie, Ruo Zhong, additional, Pravin, Vk, additional, and Prakasam, Ruby Kala, additional

Published
2008
Full Text
View/download PDF

5. The influence of surface topography of a porous perfluoropolyether polymer on corneal epithelial tissue growth and adhesion

Author

Timothy C. Hughes, John S. Wilkie, Gail A. McFarland, Hassan Chaouk, Keith M. McLean, Deborah F. Sweeney, John G. Steele, Beatrice A. Dalton, Graham Johnson, Gordon Francis Meijs, Ruo Zhong Xie, Sarah Taylor, Margaret D. M. Evans, Hans H. Griesser, Evans, Margaret DM, Chaouk, Hassan, Wilkie, John S, Dalton, Beatrice A, Taylor, Sarah, Xie, Ruo Zhong, Hughes, Timothy C, Johnson, Graham, McFarland, Gail A, Griesser, Hans H, Steele, John G, Meijs, Gordon F, Sweeney, Deborah F, and McLean, Keith M

Subjects
Materials science, Surface Properties, fluoropolymer, Biophysics, Biocompatible Materials, Bioengineering, Permeability, Cornea, Biomaterials, chemistry.chemical_compound, In vivo, cornea, medicine, Animals, Porosity, Corneal epithelium, chemistry.chemical_classification, Fluorocarbons, Epithelium, Corneal, Membranes, Artificial, in vitro, Prostheses and Implants, Polymer, eye diseases, in vivo, medicine.anatomical_structure, Membrane, chemistry, Mechanics of Materials, Cats, Ceramics and Composites, Fluoropolymer, Epithelial tissue, Ethers, Biomedical engineering
Abstract

Design principles for corneal implants are challenging and include permeability which inherently involves pore openings on the polymer surface. These topographical cues can be significant to a successful clinical outcome where a stratified epithelium is needed over the device surface, such as with a corneal onlay or corneal repair material. The impact of polymer surface topography on the growth and adhesion of corneal epithelial tissue was assessed using porous perfluoropolyether membranes with a range of surface topography. Surfaces were characterised by AFM and XPS, and the permeability and water content of membranes was measured. Biological testing of membranes involved a 21-day in vitro tissue assay to evaluate migration, stratification and adhesion of corneal epithelium. Similar parameters were monitored in vivo by surgically implanting membranes into feline corneas for up to 5 months. Data showed optimal growth and adhesion of epithelial tissue in vitro when polymer surface features were below a 150 nm RMS value. Normal processes of tissue growth and adhesion were disrupted when RMS values approached 300 nm. Data from the in vivo study confirmed these findings. Together, outcomes demonstrated the importance of surface topography in the design of implantable devices that depend on functional epithelial cover. Refereed/Peer-reviewed

Published
2011

Catalog

Books, media, physical & digital resources
See catalog results