Effects of Hydrogen Peroxide on Common Aviation Textiles
Modern transportation systems are subject to unintentional contamination from infected passengers, as well as deliberate contamination from criminals and political adversaries. Hydrogen peroxide has been used for years as a disinfectant in the medical community and is under consideration in the dilute vapor form as a decontaminant/disinfectant/sterilant for transportation vehicles like aircraft, buses, subway trains, ambulances, etc. Although the biological efficacy of STERIS Corporation’s Vaporized Hydrogen Peroxide (VHP® a registered trademark of the STERIS Corporation, Mentor, OH) technology has been demonstrated elsewhere, the compatibility of the process with typical aircraft materials has not been rigorously established. The present report documents a materials compatibility evaluation involving the effects of hydrogen peroxide exposure on the mechanical properties and flammability of the following commercial-grade textile materials: wool, nylon, polyester, Nomex®, and leather.
Vaporized Hydrogen Peroxide (VHP) Decontamination of a Section of a Boeing 747 Cabin
Abstract : The use of STERIS Corporation's Vaporized Hydrogen Peroxide (VHP)* technology as a potential biocide for aircraft decontamination was demonstrated in a cabin section of the Aircraft Environment Research Facility (an FAA-owned Boeing 747). When exposed to an appropriate concentration of VHP vapor in the cabin test section, biological indicators inoculated with 106 colony forming units of Geobacillus stearothermophilus spores demonstrated a total suppression of culture growth. Efficacy was demonstrated with and without seats in the test section of the aircraft. The importance of adequate air mixing was also demonstrated. *VHP is a registered trademark of the STERIS Corporation.
Cross talk between redox signalling and metabolic activity of osteoblasts and fibroblasts in the presence of hydroxyapatite-based biomaterials influences bone regeneration
Regeneration of bone tissue defects that result from metabolic disorders, including periodontal diseases, can be supported by biomaterials based on hydroxyapatite. Despite of good biocompatibility of biomaterials they can cause oxidative stress and inflammatory processes as a result of mechanical interaction with surrounding tissues. Because osteoblasts are responsible for bone regeneration process in which gingival fibroblasts may also participate, the aim of the work was to investigate the influence of hydroxyapatite-based biomaterials (allogeneic and xenogeneic) and biomaterials combined with enamel matrix derivative (Emdogain) on osteoblast and fibroblast redox balance in the context of osteoblast proliferation and differentiation.
The results showed that examined substitutes were not cytotoxic in vitro, but affected redox balance of osteoblasts and fibroblasts (ROS level increase and GSH level decrease) which led to oxidative stress (MDA and protein carbonyl groups level increase) resulting in an increase of the Nrf2 and NFκB expression. The consequence of these changes was partial inhibition of proliferation and osteoblast differentiation. Emdogain alone and combined with biomaterials decreased ROS generation and increased GSH level in both osteoblasts and fibroblasts leading to reduction of transcription factors expression especially proinflammatory NFκB, which promoted osteoblast differentiation and mineralization process.