Local anesthetics as a tool for Staphylococcus spp. control: a systematic review

The objective of this work was to carry out a systematic review on the effectiveness of local anesthetics as antimicrobial agents against Staphylococcus spp. Searches were performed in the PubMed, Web of science, Scopus, Embase and Lilacs databases. As inclusion criteria, complete original articles, with in vitro experimental tests with the application of selected anesthetics and bacteria of the genus Staphylococcus spp. This review followed the methodological checklist for writing papers reporting systematic reviews by the PRISMA statement. The risk of bias was assessed according to the JBI critical appraisal checklist. Analysis was performed using an anesthetic-moderated simple linear regression model. This systematic review was registered by the Open Science Framework-OSF ( https://doi.org/10.17605/OSF.IO/C5JM7 ). Initially, 1141 articles were found, of which, after careful selection, 52 articles were analyzed. Lidocaine was the most commonly used anesthetic, being evaluated in 35 of the articles. S. aureus ATCC 25923 was the standard microorganism in 17 articles. The impact of the anesthetic concentration in relation to the antimicrobial effect was evaluated and the results showed that there was no statistically significant difference. (F [5, 12] = 0.688 p = 0.642), even when taking into account the moderator effect of anesthetics individually. Therefore, although the antimicrobial effect of local anesthetics was demonstrated in 82.7% of the studies evaluated, great heterogeneity of the results was found, which made it impossible to carry out a meta-analysis and make recommendations based on the evidence.

"Relationship between antibiotic resistance, biofilm formation, virulence factors and source of origin of Pseudomonas aeruginosa environmental isolates with regard to the presence of metallo-β-lactamase-encoding genes"

A total of 557 water samples were evaluated and of these, 23 were positive for the presence of Pseudomonas aeruginosa. Approximately 91.7% of them were weak biofilm formers. Only 4 isolates showed antimicrobial resistance. All isolates presented Twitching motility, a positive result for the production of pyocyanin, alkaline protease, and hemolysins. The genotypic tests showed: lasA, (95.6%) lasB (95.6%), exoS (95.6%), exoT (91.3%), toxA (91.3%), akgO (91.3%), plcN (91.3%) aprA (86.9%), phzM (78.3%), and pvdA (60.9%). For genes encoding metallo-beta-lactamase, it was found: blaVIM (56.6%), blaSPM (4.3%), and blaSIM (47.8%). A strong association was found between the metallo-beta-lactamase producing genes, nine genes of virulence factors and the motility (r = 0.6231). The very close clonal profile suggests a probable similarity between the isolates from different cities. Thus, P. aeruginosa can be present in water supplies with variable virulence capacities and can generate a huge concern for human, animal, and environmental health.