Nanoformulated meloxicam and rifampin: inhibiting quorum sensing and biofilm formation in Pseudomonas aeruginosa.

Background: We aimed to investigate the simultaneous effects of meloxicam and rifampin nanoformulations with solid lipid nanoparticle (SLN) and nanostructured lipid carrier (NLC) substrates on inhibiting the quorum-sensing system of Pseudomonas aeruginosa and preventing biofilm formation by this bacterium. Methods: Antimicrobial activity of rifampin and meloxicam encapsulated with SLNs and NLCs against P. aeruginosa PAO1 was assessed by disk diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Results: The SLN formulation was associated with lower doses for the MIC and minimum bactericidal concentration in comparison to NLC. Moreover, our results demonstrated that both nanoformulations were able to produce 100% inhibition of the biofilm formation of P. aeruginosa PAO1. Conclusion: All these findings suggest that meloxicam and rifampin encapsulated with SLNs could be the most effective formulation against P. aeruginosa.

Antimicrobial resistances, and molecular typing of Campylobacter jejuni isolates, separated from food-producing animals and diarrhea patients in Iran.

The aims of this study were to regain new epidemiology information about frequency, drug resistance rates, and typing of Campylobacter jejuni (C. jejuni) isolates, obtained from some poultry and cattle farms, slaughterhouses, and people with diarrhea. In this regard, Minimal Inhibitory Concentration (MIC) of several antibiotics and the associated antibiotic resistance genes, including tetO, tetA, cmeB, and blaOXA-61 were evaluated. The isolates were also typed, using the Fla-RFLP method. Generally, between 233 food animal samples, 80 (34.33%) C. jejuni were isolated. Moreover, 20 out of 74 (27%) human specimens suspected to infectious diarrhea were C. jejuni positive. High frequencies of resistance to tetracycline (100%), ciprofloxacin (95%), and nalidixic acid (86%), and low frequencies of resistance to florfenicol (0%), erythromycin (5%), and gentamicin (8%) were observed. Furthermore, in the tetracycline-resistant isolates, the existences of tetO, tetA, and cmeB were 86%, 23%, and 48%, respectively. There was a significant correlation between the cluster types obtained from Fla-RFLP method and antibiotic resistance pattern. The results suggested that the genomic link between Campylobacter spp. should be always evaluated in each country to provide an insight about the Campylobacter spp., spread in the region, in order to implement the health-controlling programs efficiently.