30 human brains?
Multi-enrichment to get to the glycoprotein/peptide patterns? Check this out!
They used "healthy" brains, brains from people who had alzheimer's but were asymptomatic, and some from those who had symptoms at point of death?
Would you be surprised by differing patters of glycan distribution? Me either, but I'd have no idea what to do with those data.
What really shines in this paper, besides the obvious biological importance and loads of work that went into it is how they visualize the patterns of their observations.
If you're wondering what to do with glycoproteomics data this is definitely worth a look. Frustrating things about these PTMs are (among many) the fact that your biology might be that one sugar may be over/under represented in the glycan chains observed. How on earth do you display that?? Like they did.