The antiproliferative effects of cold atmospheric plasma-activated media on different cancer cell lines, the implication of ozone as a possible underlying mechanism.

Recent studies have proven several promising anticancer activities for cold atmospheric plasma (CAP) against a wide range of cancer cells in vitro. Recently, media treated with CAP have also found to effectively eradicate cancer cells similar to the CAP. Based on advantages, many researchers prefer to apply CAP-activated media (PAM) as an alternative to cap in the treatment of cancer. However, less has been achieved regarding the anticancer effects and anticancer mechanisms of PAM. Investigating the selective anticancerous activities of PAM, the viability of SKBR3, MCF7, ASPC-1, A-549, G-292, and SW742 cancer cell lines, as well as normal human skin fibroblasts (FMGB-1) and MCF10A cells in relation to the media activation time, and the length of exposure was studied. Also, we examined the concentration of ozone in media as a function to CAP activation time since recent studies have proposed ozone as a pivotal reactive species in the induction of cell death. Based on the result, both increasing the duration of media activation time and the length of exposure to PAM could significantly increase the anticancer activity. Nevertheless, the cytotoxicity on normal cells was either not affected or slightly increased. Among the six tested cancer cell lines, SW742 was the most resistant and SKBR3 the most susceptible cancer cell lines to PAM. Also, increasing duration of treatment with CAP resulted in a significant rise in O3 concentration levels in media. Overall, these results suggest PAM, as a promising tool in the treatment of different cancers and O 3 formation as a probable underlying mechanism.

Evaluating the Frequency of aac(6')-IIa, ant(2″)-I, intl1, and intl2 Genes in Aminoglycosides Resistant Klebsiella pneumoniae Isolates Obtained from Hospitalized Patients in Yazd, Iran.

BACKGROUND: Klebsiella pneumoniae (K. pneumoniae) is an opportunistic pathogen that could be resistant to many antimicrobial agents. Resistance genes can be carried among gram-negative bacteria by integrons. Enzymatic inactivation is the most important mechanism of resistance to aminoglycosides. In this study, the frequencies of two important resistance gene aac(6')-IIa and ant(2″)-I, and genes coding integrase I and II, in K. pneumoniae isolates resistant to aminoglycosides were evaluated. METHODS: In this cross-sectional study, an attempt was made to assess the antibiotic susceptibility of 130 K. pneumoniae isolates obtained from different samples of patients hospitalized in training hospitals of Yazd evaluated by disk diffusion method. The frequencies of aac(6')-IIa, ant(2″)-I, intl1, and intl2 genes were determined by PCR method. Data were analyzed by chi-square method using SPSS software (Ver. 16). RESULTS: our results showed that resistance to gentamicin, tobramycin, kanamycin, and amikacin were 34.6, 33.8, 43.8, and 14.6%, respectively. The frequencies of aac (6')-IIa, ant(2″)-I, intl1, and intl2 genes were 44.6, 27.7, 90, and 0%, respectively. CONCLUSION: This study showed there are high frequencies of genes coding aminoglycosides resistance in K. pneumoniae isolates. Hence, it is very important to monitor and inhibit the spread of antibiotic resistance genes.