I.S. Raginov Dr.Sc. (Med.), Head of Department of Pathology Republican Clinical Hospital, Associate Professor, Department of Histology, Kazan State Medical University, Kazan, Russia. E-mail: raginovi@mail.ru G.V. Vafina Post-graduate Student, Department of Histology, Kazan State Medical University, Kazan, Russia L.R. Valiullin Ph.D. (Vet.), Deputy Director of «Bionanoteh», Kazan, Russia M.V. Lekishvili Dr.Sc. (Med.), Head of Laboratory «Tissue Bank», N.N. Priorov Research Institute of Traumatology and Orthopaedics, Moscow, Russia. E-mail: leki@mail.ru