Methods are disclosed for detecting and measuring polysaccharide-hydrolyzing enzyme activity or concentration by partial hydrolysis using a pre-determined, yet short, incubation time and a pre-determined temperature. The resulting reaction mixture has unique chemical (i.e., reaction products) and physical (i.e., viscosity) properties that can be used to detect or measure the polysaccharide-hydrolyzing enzyme activity or concentration.

Provided herein are methods of measuring glycogen and methods of diagnosing a disease. One method of measuring includes separating sugar monomers and sugar phosphates using gas-chromatography, and analyzing the monomers and phosphates using mass spectrometry. Another method of measuring includes adding an isoamylase to a sample, the isoamylase cleaving glucose chains from glycogen; applying a matrix-assisted laser desorption ionization (MALDI) ionization matrix to the sample; and analyzing the samples using matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). The method of diagnosing a disease includes determining an amount and location of glycogen accumulation in a subject; and diagnosing a disease when over-accumulation of glycogen is determined.

Disclosed are a deer-derived specific peptide and a detection method therefor; by screening through a large number of experiments, a ratio of relative contents of two deer-derived peptides is determined, and a graph is drawn by using a proportion of a deer antler gelatin in a mixed gelatin as an abscissa and using a value of A.sub.peptide .sub.1/A.sub.peptide .sub.2 as an ordinate; the proportion of the deer antler gelatin is linear with A.sub.peptide .sub.1/A.sub.peptide .sub.2 as a standard curve equation to distinguish a deer hide gelatin from the deer antler gelatin; the method can be used for distinguishing the deer antler gelatin from the deer hide gelatin, and controlling the quality; a defect in the prior art that the deer antler gelatin and the deer hide gelatin are difficult to distinguish in appearance, and are also difficult to distinguish by using a specific peptide fragment, is solved.

Methods are disclosed for detecting and measuring polysaccharide-hydrolyzing enzyme activity or concentration by partial hydrolysis using a pre-determined, yet short, incubation time and a pre-determined temperature. The resulting reaction mixture has unique chemical (i.e., reaction products) and physical (i.e., viscosity) properties that can be used to detect or measure the polysaccharide-hydrolyzing enzyme activity or concentration.

Disclosed are a deer-derived specific peptide and a detection method therefor; by screening through a large number of experiments, a ratio of relative contents of two deer-derived peptides is determined, and a graph is drawn by using a proportion of a deer antler gelatin in a mixed gelatin as an abscissa and using a value of A.sub.peptide 1/A.sub.peptide 2 as an ordinate; the proportion of the deer antler gelatin is linear with A.sub.peptide 1/A.sub.peptide 2 as a standard curve equation to distinguish a deer hide gelatin from the deer antler gelatin; the method can be used for distinguishing the deer antler gelatin from the deer hide gelatin, and controlling the quality; a defect in the prior art that the deer antler gelatin and the deer hide gelatin are difficult to distinguish in appearance, and are also difficult to distinguish by using a specific peptide fragment, is solved.

The present invention relates to a biomarker panel for the diagnosis or prediction of brain metastasis of lung cancer and a method for the diagnosis or prediction of metastatic brain tumors by using the panel. Accuracy and sensitivity in diagnosing lung cancer brain metastases were improved by providing a biomarker screened from pure tumor cells, beyond the limitations of biomarkers screened on the basis of bulk data of mixed tumor cells and cancer microenvironment cells.