Aims: Non-thermal atmospheric-pressure plasma (cold plasma), is described as a partly ionized gas. Cold plasma is a new method of medicine for killing the bacteria, treatment of cancer diseases, accelerates the healing of infectious ulcers, especially in infection caused by Meticillin-resistant Staphylococcus aureus (MRSA). This study aimed to investigate the impact of Non-thermal atmospheric-pressure plasma on MRSA S. aureus organism isolated from burn wound infection in vitro and in vivo. Methodology and results: Five MRSA S. aureus strains were recovered in burn patients from Shahid Motahari Burns Hospital, Tehran, Iran. They confirmed by microbiology and biochemical tests. Antibiotic susceptibility testing was performed using Kirby Bauer Disk Diffusion Method with selected antibiotics. Then, the antibacterial impact of atmospheric non-thermal plasma on MRSA in vitro and in vivo at different times was assessed. After that, the tissue was randomly separated from control and treated mice with plasma and transferred to the Histopathology Laboratory for further evaluation. Results of the inactivation of MRSA by non-thermal atmospheric plasma showed no bacterial growth. Also, results of the impact of non-thermal helium plasma in vivo environment revealed that, in addition to healing in the animal wound, the burn wounds infection was healed and treated according to the histological results. Conclusion, significance and impact of study Our results confirmed the inactivation of MRSA S. aureus, healing of animal burn wound and complete treatment by non-thermal atmospheric plasma. It recommended that cold plasma can be used for the treatment of burn wounds infection due to the gentle on the human skin.

BACKGROUND: In the aftermath of bone injuries, such as cranium and sternum, bone wax (BW) is used to control bleeding from the bone surfaces during surgery. Made up of artificial substances, however, it is associated with many complications such as inflammation, increased risk for infection, and bone repair delay. We, therefore, in this study set out to design and evaluate a novel BW without the above-mentioned side-effects reported for other therapies. METHODS: The pastes (new BW(s)) were prepared in the laboratory and examined by MTT, MIC, MBC, and degradability tests. Then, 60 adult male Wistar rats, divided into six equal groups including chitosan (CT), CT-octacalcium phosphate (OCP), CT-periostin (Post), CT-OCP-Post, Control (Ctrl), and BW, underwent sternotomy surgery. Once the surgeries were completed, the bone repair was assessed radiologically and thereafter clinically in vivo and in vitro using CT-scan, H&E, ELISA, and qRT-PCR. RESULTS: All pastes displayed antibacterial properties and the CT-Post group had the highest cell viability compared to the control group. In contrast to the BW, CT-Post group demonstrated weight changes in the degradability test. In the CT-Post group, more number of osteocyte cells, high trabeculae percentage, and the least fibrous connective tissue were observed compared to other groups. Additionally, in comparison to the CT and Ctrl groups, higher alkaline phosphatase activity, as well as decreased level of serum tumor necrosis factor-a, interleukin-6, and OCN in the CT-Post group was evident. Finally, Runx2, OPG, and RANKL genes’ expression was significantly higher in the CT-Post group than in other groups. CONCLUSION Our results provide insights into the desirability of pastes in terms of cellular viability, degradability, antibacterial properties, and surgical site restoration compared to the BW group. Besides, Periostin could enhance the osteogenic properties of bone tissue defect site.