Before revision:  interesting results  were found.
After revision:  interesting results (e.g. (i) the species that has the clearly and highly ordered S2-H2 loop usually owns a 3-10-helix in this loop, (ii) a "pi-circle" Y128-F175-Y218-Y163-F175-Y169-R164-Y128(-Y162) is around the S2-H2 loop of prion protein structures) were found.