RESUMO
We report patho-morphological and virological characterization of SARS-CoV-2 in naturally infected, free ranging Indian Leopard (Panthera pardus fusca). Whole genome sequence analysis confirmed infection of Delta variant of SARS-CoV-2, possibly spill over from humans, but the case was detected when infection level had dropped significantly in human population. This report underlines the need for intensive screening of wild animals for keeping track of the virus evolution and development of carrier status of SARS-CoV-2 among wildlife species.
RESUMO
BACKGROUND: Stem cell is currently playing a major role in the treatment of number of incurable diseases via transplantation therapy. The objective of this study was to determine the osteogenic potential of allogenic and xenogenic bone-derived MSC seeded on a hydroxyapatite (HA/TCP) bioceramic construct in critical size bone defect (CSD) in rabbits. METHODS: A 15 mm long radial osteotomy was performed unilaterally in thirty-six rabbits divided equally in six groups. Bone defects were filled with bioscaffold seeded with autologous, allogenic, ovine, canine BMSCs and cell free bioscaffold block in groups A, B, C, D and E respectively. An empty defect served as the control group. RESULTS: The radiological, histological and SEM observations depicted better and early signs of new bone formation and bridging bone/implant interfaces in the animals of group A followed by B. Both xenogenous MSC-HA/TCP construct also accelerated the healing of critical sized bone defect. There was no sign of any inflammatory reaction in the xenogenic composite scaffold group of animals confirmed their well acceptance by the host body. CONCLUSION: In vivo experiments in rabbit CSD model confirmed that autogenous, allogenous and xenogenous BMSC seeded on bioscaffold promoted faster healing of critical size defects. Hence, we may suggest that BMSCs are suitable for bone formation in fracture healing and non-union.
