1. National Hellenic Research Foundation, 11635 Athens, Greece
2. Nasco AD Biotechnology Laboratory, 18536 Pireus, Greece
3. Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, 2371 Nicosia, Cyprus
4. Laboratory of Clinical Virology, Medical School, University of Crete, 71003 Heraklion, Greece