1 1Department of Microscopy,Laboratory of Cell Biology,Institute of Biomedical Sciences Abel Salazar,University of Porto,Multidisciplinary Unit for Biomedical Research (UMIB),Rua Jorge Viterbo Ferreira,228,4050-313 Porto,Portugal.
2 2Centre for Reproductive Genetics Prof. Alberto Barros (CGR-ABarros),Av. do Bessa,240,1º Dto. Frente,4100-009 Porto,Portugal.