Article

Studies of keratins in tongue coating samples of hepatitis B patients by mass spectrometry.

Shanghai Mass Spectrometry Center, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.
Rapid Communications in Mass Spectrometry (Impact Factor: 2.51). 07/2009; 23(11):1703-9. DOI: 10.1002/rcm.4060
Source: PubMed

ABSTRACT Pooled tongue coating samples from 64 hepatitis B patients and 24 healthy adults were studied and a major band of differential proteins was found by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The differential proteins in this band were identified and proved to be keratins by liquid chromatography/tandem mass spectrometry (LC/MS/MS) and Western blot analysis. Furthermore, relative quantification of the identified keratins was performed via using stable isotopic labeling and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), showing the higher expression level of these keratins in tongue coating samples of hepatitis B patients than healthy adults. These results provided additional information to understand the medical diagnosis depending on the tongue coating.

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