Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/34598
Title: Variability of tear protein levels in normal young adults : between-day variation
Authors: Ng, V
Cho, P 
Mak, S
Lee, A
Issue Date: 2000
Publisher: Springer
Source: Graefe's archive for clinical and experimental ophthalmology, 2000, v. 238, no. 11, p. 892-899 How to cite?
Journal: Graefe's archive for clinical and experimental ophthalmology 
Abstract: Background: An adequate knowledge of physiological variation is important for valid comparative studies of tear proteins. The aim of this study was to investigate the between-day variation of the human tear protein levels, including the total protein concentration (TPC) and the levels of major protein fractions. Two sampling methods, the yawn and the eye-flush methods, were used and compared.
Methods: TPC was determined by the Bradford method. The major protein fractions were separated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) and their levels were determined by scanning densitometry after SDS-PAGE. The tear protein levels were monitored for 3 days.
Results: The between-day differences in the levels of TPC and the individual protein fractions were not statistically significant in either sampling method, but the variations of some proteins were large and would be clinically significant. Different variations were observed in different proteins. The variations in serum albumin were large, up to 61% and 113% in the yawn and eye-flush methods respectively. The variations in lactoferrin, tear-specific prealbumin and lysozyme were relatively small in the yawn method. The variations in protein levels obtained by the eye-flush method were generally higher than by the yawn method.
Conclusion: Although the between-day differences in tear protein levels were not statistically significant, the variations in some proteins would be large in magnitude. The variability of tear protein levels obtained by the eye-flush method was larger than that by the yawn method. Therefore, caution should be taken if the eye-flush method is used for sampling tears for quantitative analysis of tear proteins, although it is easier to collect tear samples using this method. The results will be useful to exclude normal variation in tear protein levels when comparing pre- and post-therapeutic tear protein levels in eyes treated for tear-related abnormalities.
URI: http://hdl.handle.net/10397/34598
ISSN: 0721-832X
EISSN: 1435-702X
DOI: 10.1007/s004170000165
Appears in Collections:Journal/Magazine Article

Access
View full-text via PolyU eLinks SFX Query
Show full item record

WEB OF SCIENCETM
Citations

27
Last Week
0
Last month
Citations as of Aug 15, 2017

Page view(s)

35
Last Week
1
Last month
Checked on Aug 13, 2017

Google ScholarTM

Check

Altmetric



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.