- Solid-state NMR studies of the secondary structure of a mutant prion protein fragment of 55 residues that induces neurodegeneration. Laws, D.D., Bitter, H.M., Liu, K., Ball, H.L., Kaneko, K., Wille, H., Cohen, F.E., Prusiner, S.B., Pines, A., Wemmer, D.E. Proc. Natl. Acad. Sci. U.S.A. (2001)