Decreased mucin concentrations in tear fluids of contact lens wearers

Comparative studies of HPLC-fluorometry and LC/MS method for the determination of N-acetylneuraminic acid as a marker of deteriorated ophthalmic solutions

“…We previously reported that NeuAc which is the characteristic monosaccharide component in tear fluids is a good marker for dry eyes [13]. Based on these previous studies, contaminating substances due to tear fluids are considered to be confirmed by detecting NeuAc.…”

“…However, a more robust, rapid and quantifiable technique is needed for effective screening of potentially contaminated products. As indicated above, the authors previously reported a method for mucin determination in tear fluids by HPLC with fluorometry using NeuAc as a marker [13]. In the present report, a technique for NeuAc determination using LC/MS method was compared with the previously reported method.…”

“…For example, during the investigation of the role of protease-activated receptor-2 (PAR-2) in the rat salivary glands, Kawabata et al described the use of NeuAc as an indicator of salivary mucin secretion triggered by PAR-2 activation [12]. Our group has also shown, using NeuAc as a marker, that mucin concentrations were significantly decreased in tear fluids of contact lens wearers [13].…”

Evaluation of the Frequency of Ophthalmic Solution Application: Washout Effects of Topical Saline Application on Tear Components

“…Procedures for analyzing sialic acids were based on the report by Yasueda et al 17 A volume of 10 ml of each eluted tear protein extract was mixed with 10 ml of 4 M acetic acid and kept at 80 C for 3 h to release sialic acids. A mixture of 200 ml of DMB solution, coupling solution (containing acetic acid, b-mercaptoethanol and sodium hydrosulfite), and water (1:5.4) was added.…”

A Protein Dye-Binding Assay on Cellulose Membranes for Tear Protein Quantification

“…[9][10][11] Even so, the low abundance of tear fluid has often limited the ophthalmologist to focus on just a few specific biochemical variables and to express the results as the mass of the analyte per unit volume of tear fluid. [3][4][5]7,8,[12][13][14][15][16][17] However, the protein content in a sample under study is often an important reference parameter in biochemical analysis. Thus, the presence of a specific analyte in a biologic sample is often expressed as the mass of the analyte per mass (in milligrams) of total protein.…”