Sciatic Nerve Plastic Surgery using Autologous Adipose Tissue.

The aim of the investigation is to study structural alterations of autologous omental adipose tissue in a silicon conduit and to evaluate its possible use for regeneration of the sciatic nerve in diastasis. Materials and Methods: Mature outbred male Wistar rats have been used in the study. The animals were divided into 7 experimental groups with complete transection of the sciatic nerve on the right side at the mid-third level of the thigh. The ends of the transected nerve were pulled apart, inserted into a silicon conduit, and secured to the epineurium. The conduit of group 1 (control) was filled with a saline solution; in group 2, it was filled with an autologous omental adipose tissue with saline solution. Intravital labeling of the omental adipose tissue with the lipophilic PKH 26 dye (in group 3) was used for the first time to find out whether the omental cells were involved in formation of the regenerating nerve. Diastasis in groups 1-3 was 5 mm, the postoperative period was 14 weeks. The dynamics of the omental adipose tissue changes in groups 4-7 was assessed by placing the omental tissues into the conduit covering 2 mm of diastasis. The postoperative period was 4, 14, 21, and 42 weeks. Results: In group 2 (omental adipose tissue + saline), the clinical condition of the damaged limb after 14 weeks may be evaluated as satisfactory and approximating to the intact parameters as compared to group 1 where the conduit was filled with a saline solution only. The sum of large and medium-sized nerve fibers in group 2 was 2.7 times greater than that in group 2. The milled omental adipose tissue inside the conduit changed its volume and structure in nerve diastasis and was constantly utilized up to complete elimination over time. The omental cells integrated into the newly formed nerve in the graft area. Conclusion: As a graft, the adipose tissue of the autologous omentum produces a stimulating effect on the post-traumatic regeneration of the sciatic nerve.

In vivo monitoring of vascularization and oxygenation of tumor xenografts using optoacoustic microscopy and diffuse optical spectroscopy.

The research is devoted to comparison of the blood vessel structure and the oxygen state of three xenografts: SN-12C, HCT-116 and Colo320. Differences in the vessel formation and the level of oxygenation are revealed by optoacoustic (OA) microscopy and diffuse optical spectroscopy (DOS) respectively. The Colo320 tumor is characterized by the highest values of vessel size and fraction. DOS showed increased content of deoxyhemoglobin that led to reduction of saturation level for Colo320 as compared to other tumors. Immunohistochemical (IHC) analysis for CD31 demonstrates the higher number of vessels in Colo320. The IHC for hypoxia was consistent with DOS results and revealed higher values of the relative hypoxic fraction in Colo320.