Abstract: Provided is a therapeutic agent that effectively acts on a disease associated with abnormal glycosylation of dystroglycan. Also provided is a testing method for diseases associated with abnormal glycosylation of dystroglycan. Specifically, provided is a therapeutic agent for diseases associated with abnormal glycosylation of dystroglycan, containing CDP-ribitol as an active ingredient. Ribitol-phosphate is important in the glycan structure of dystroglycan. In order for ribitol-phosphate to be incorporated into a dystroglycan glycan, a material therefor (sugar donor) is required. In the present invention, it has been found for the first time that CDP-ribitol serves as the sugar donor. It has been confirmed that the glycan of ISPD-deficient cells can be restored by administering CDP-ribitol. Thus, the present invention, which allows CDP-ribitol to be utilized for supplementation therapy, has been completed.

Abstract: Provided is a therapeutic agent that effectively acts on a disease associated with abnormal glycosylation of dystroglycan. Also provided is a testing method for diseases associated with abnormal glycosylation of dystroglycan. Specifically, provided is a therapeutic agent for diseases associated with abnormal glycosylation of dystroglycan, containing CDP-ribitol as an active ingredient. Ribitol-phosphate is important in the glycan structure of dystroglycan. In order for ribitol-phosphate to be incorporated into a dystroglycan glycan, a material therefor (sugar donor) is required. In the present invention, it has been found for the first time that CDP-ribitol serves as the sugar donor. It has been confirmed that the glycan of ISPD-deficient cells can be restored by administering CDP-ribitol. Thus, the present invention, which allows CDP-ribitol to be utilized for supplementation therapy, has been completed.

Abstract: In one embodiment of the present invention, a sample target that allows ionization of a substance whose molecular weight is so high as to exceed 10000 in mass spectrometry that ionizes a sample without using matrix, a method for producing the same and a mass spectrometer using the sample target. The sample target includes a sample support surface including a large number of fine pores on its face receiving irradiated laser light. Each of the fine pores has a diameter of 30 nm or more and 5 ?m or less. The number indicative of pore depth/(pore cycle?pore diameter) of each of the fine pores is 2 or more and 50 or less. The face of the sample support surface is coated with metal or semiconductor.

Abstract: The present invention provides a simplified method for analyzing a structure of glycoprotein capable of conducting a peptide sequence analysis, a sugar chain sequence analysis, and an analysis of a sugar chain binding site accurately and rapidly using a mass spectrometer.

Abstract: In one embodiment of the present invention, a sample target that allows ionization of a substance whose molecular weight is so high as to exceed 10000 in mass spectrometry that ionizes a sample without using matrix, a method for producing the same and a mass spectrometer using the sample target. The sample target includes a sample support surface including a large number of fine pores on its face receiving irradiated laser light. Each of the fine pores has a diameter of 30 nm or more and 5 ?m or less. The number indicative of pore depth/(pore cycle?pore diameter) of each of the fine pores is 2 or more and 50 or less. The face of the sample support surface is coated with metal or semiconductor.

Abstract: The present invention provides a simplified method for analyzing a structure of glycoprotein capable of conducting a peptide sequence analysis, a sugar chain sequence analysis, and an analysis of a sugar chain binding site accurately and rapidly using a mass spectrometer.

Abstract: The present invention provides a method for improving the sensitivity of mass spectrometry for biological molecules. The present invention also provides a method for a rapid and simple analysis of biological samples by making use of the method for improving the sensitivity of mass spectrometry. A method for labeled amidation, comprising the step of reacting an amidating reagent labeled with 15N, an isotope of nitrogen, with the carboxyl group of a biological molecule. A method for analyzing a biological molecule, comprising the steps of performing amidation to a carboxyl group of a biological molecule to obtain an amidated form of the biological molecule, and subsequently subjecting the amidated form of the biological molecule to mass spectrometry. A labeled amidated form of a biological molecule wherein a carboxyl group of the biological molecule is amidated as 15N-labeled amide group.