Analysis of high-angle synchrotron x-ray diffraction patterns obtained from macular dystrophy corneas.

A J Quantock; K M Meek; E J Thonar

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PubMed · 1587124

Analysis of high-angle synchrotron x-ray diffraction patterns obtained from macular dystrophy corneas.

A J Quantock·K M Meek·E J Thonar

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Abstract

Six macular dystrophy corneas from six individuals were investigated by synchrotron x-ray diffraction. Immunochemical evidence demonstrated that five of the patients had type I macular corneal dystrophy and that one had type II. Analysis of the high-angle x-ray diffraction patterns showed that the intermolecular spacing of macular dystrophy corneal collagen increases with hydration from the dry state in a fashion similar to the intermolecular spacing of normal human corneal collagen. The high-angle x-ray diffraction pattern from all six corneas contained two "extra reflections" not obtained from other human corneas, normal or pathologic. The reflections, which arise from 4.61 and 9.62 A periodic structures, are independent of the type of macular dystrophy. Furthermore, their position is independent of corneal hydration. We propose that a glycosaminoglycan structure is the origin of the unique extra reflections.

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Collagen Cornea Corneal Dystrophies, Hereditary Female Glycosaminoglycans Humans Keratan Sulfate Male X-Ray Diffraction Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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A J Quantock, K M Meek, E J Thonar. 1992. Analysis of high-angle synchrotron x-ray diffraction patterns obtained from macular dystrophy corneas.. https://pubmed.ncbi.nlm.nih.gov/1587124/

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