Antibiotic resistance gene transfer between Streptococcus gordonii and Enterococcus faecalis in root canals of teeth ex vivo.

Multiple bacterial species coexisting in infected root canals might interact, but evidence for interspecies gene transfer is lacking. This study tested the hypothesis that horizontal exchange of antibiotic resistance can occur between different bacterial species in root canals. Transfer of the conjugative plasmid pAM81 carrying erythromycin resistance between 2 endodontic infection-associated species, Streptococcus gordonii and Enterococcus faecalis, was investigated in an ex vivo tooth model.

Behavioral and biochemical evaluation of sub-lethal inhalation exposure to VX in rats.

We evaluated the effects of low-level inhalation exposures (whole body, 60min duration) to the chemical warfare nerve agent VX (0.016, 0.15, 0.