"1) that decrease of GLUT3 is associated with the reduction of protein O-GlcNAcylation in Alzheimer's disease (AD)brain 2) that GLUT3 level is negatively correlated with calpain I activation in human brain 3) that calpain I proteolyzes GLUT3 at the N-terminus in vitro and 4) that activation of calpain I is negatively correlated with protein O-GlcNAcylation in AD brain."xsd:string