Sensitivity of two drug-resistant bacteria to low-temperature air plasma in catheterassociated urinary tract infections under different environments

The high incidence of catheter-associated urinary tract infections,which are dominated by drugresistant bacteria,has attracted an increasing number of researchers interested in solving this public health problem.The purpose of this study was to explore the killing effect of lowtemperature air plasma(LTAP)on extended-spectrum beta-lactamase-producing Escherichia coli and high level gentamycin resistance enterococci under two simulated environments in vitro.The results showed that the survival rate of these two kinds of bacteria decreased to less than20%after being treated by LTAP in different environments for 5 min.A comparison of the LTAP treatments showed that the killing efficacy of the two kinds of bacteria in the early stage(0-1 min)was up to 50%.Moreover,the results of transmission electron microscopy,reactive nitrogen species measurement,and a temperature test indicated that the bactericidal effect of the LTAP treatment on the two kinds of bacteria worked through the destruction of the ribosome and other organelles inside the bacteria,rather than the thermal effect,to achieve sterilization.

Cold air plasma:A potential strategy for inducing apoptosis of rheumatoid arthritis fibroblast‐like synoviocytes

Rheumatoid arthritis(RA)is an autoimmune disease of the joints characterised by synovial hyperplasia and chronic inflammation.Rheumatoid arthritis fibroblast‐like synoviocytes(RA‐FLS)cells are the dominant cell type in the hyperplastic synovial membrane,which play a key role in the pathogenesis of RA.They can invade cartilage,cause inflammation,destroy joints,and show tumour‐like anti‐apoptosis characteristics.Thus,the purpose of this study is to investigate the effect of cold air plasma(CAP)on RA‐FLS cells.The results showed that CAP treatment for 120 s could significantly reduce the viability of RA‐FLS cells,increase the content of intracellular reactive ox-ygen species(ROS),and significantly down‐regulate the ratio of apoptosis‐related protein Bcl‐2 to Bax.In this study,a novel approach of inducing apoptosis in RA‐FLS cells using CAP was proposed,which may provide a new choice for joint tar-geting therapy of RA.