EFFECT OF XENOGRAFTS SATURATED WITH SILVERNANOCRYSTALS ON HISTOLOGICAL STRUCTURE OF THE SKIN IN THE DYNAMICS OF EXPERIMENTAL THERMAL INJURY.

The aim of this study was to establish histological state of the components of the affected area of skin in cases of application of xenograft saturated with silver nanocrystals in the dynamics after experimental thermal injury. The study was performed on 54 adult guinea pigs following the rules of bioethics. Experimental animals were divided into two groups: the 1st - animals with severe thermal injury (27); the 2nd - animals with burn injury (27), in which the wounds were covered with xenograft after early necrectomy of the damaged tissues. To investigate the microscopic changes in the skin the animals were removed from the experiment on the 7th, 14th, and 21st days of the experiment. Histological sections were stained with hematoxylin and eosin. Application of xenograft saturated with silver nanocrystals for 7 days contributes to formation of granulation tissue, activation of regenerative mechanisms in the marginal areas of the wound. On the 14th day of the experiment, an epidermal regenerate was evidenced at the wound, its formation source was the perifocal areas of the epidermis and skin appendages, and below it - fibroblastic cells rich granulation tissue, well-defined fibrous structures, equally set components of the hemomicrocirculatory flow. On the 21st day, a well-formed epidermis with a clear differentiation of cells into layers was observed. In the fresh connective tissue, formation of papillae with new capillaries embedded in the epithelium was evidenced. There were collagen as well as elastic fibres among the fibrous structures of the intercellular substance of the connective tissue. In all stages of the experiment with application of xenograft saturated with silver nanocrystals no purulonecrotic masses were observed in the affected area. Thus, histologically it has been found out that application of xenograft saturated with silver nanocrystals after early necrectoна руссmy of burn-damaged areas of the skin at an early stage improves formation of granulation tissue. In the late post-experimental thermal injuries, their usage accelerates epithelialization, connective tissue formation and has positive effect on the course of the experimental burn wound process.