FEATURES OF FORMATION OF BACTERIAL BIOFILMS IN CONDITIONS OF SPACE FLIGHT

Aim. Study the effect of microgravitation on the formation of Lactobacillus plantarum 8PA-3 bacterial biofilms in the conditions of space flight. Materials and methods. Information on the effect of microgravitation on the development of biofilms was obtained during study of L. plantarum 8PA-3 probiotic lactobacilli in special equipment in the process of execution of space experiments in the Russian segment of the International Space Station. Comparative analysis of growth of plankton and biofilm forms of cells developing in the conditions of space flight and surface conditions was carried out by microbiologic and electron-microscopy methods using scanning and transmission electron microscopy. Results. Accelerated dynamics of formation of L. plantarum 8PA-3 lactobacilli biofilm on the surface of polymer substrate was shown for the first time during the space experiment. Microbiological analysis of the bacterial culture has also confirmed the accelerated growth of L. plantarum 8PA-3 under microgravitation compared with surface conditions. Ultrastructure of plankton form of L. plantarum 8PA-3 taking part in formation of biofilms in conditions of microgravitation was detected for the first time in the space experiment. Conclusion. Data on comparative electron-microscopic analysis obtained in space experiments are important for scientific justification of the effect of microgravitation on bacterial communities developing as biofilms - the most natural form of existence of microorganisms. The results obtained could be taken into consideration during creation of novel antibacterial means and disinfectants as well as methods of treatment of surfaces of modules of piloted space complexes that could allow to clarify methods of effective prophylaxis of biofilm spread which pose a risk of health of the crew and normal functioning of equipment in the International Space Station

Porous composite prosthetic pylon for integration with skin and bone

This article presents results of the further development and testing of the skin and bone integrated pylon (SBIP-1) for percutaneous (through skin) connection of the residual bone with an external limb prosthesis. We investigated a composite structure (called the SBIP-2) made of titanium particles and fine wires using mathematical modeling and mechanical testing. Results showed that the strength of the pylon was comparable with that of anatomical bone. In vitro and in vivo animal studies on 30 rats showed that the reinforcement of the composite pylon did not compromise its previously shown capacity for inviting skin and bone cell ingrowth through the device. These findings provide evidence for the safe and reliable long-term percutaneous transfer of vital and therapeutic substances, signals, and necessary forces and moments from a prosthetic device to the body