[1] Univ Politecn Madrid, Fac Informat, Dept Inteligencia Artificial, Biomed Informat Grp, E-28660 Madrid, Spain
[2] Univ Patras, Patras 26504, Greece
[3] Univ Patras, Comp Technol Inst & Press Diophantus, Rion 26504, Greece
[4] Acad Athens, Biomed Res Fdn, Bioinformat & Med Informat Grp, Athens 11527, Greece