Group C Streptococcus dysgalactiae subsp. equisimilis in south-east Brazil: genetic diversity, resistance profile and the first report of human and equine isolates belonging to the same multilocus sequence typing lineage Universidade Federal do Rio de Janeiro, Instituto de Microbiologia Paulo de Gó es, RJ, Brazil Streptococcus dysgalactiae subsp. equisimilis (SDSE) isolates are the most common group C streptococci in humans and reports of invasive infections associated with SDSE have been increasing. Molecular epidemiology studies are an important strategy to trace the emergence and spread of possible well-fit bacterial pathogens of humans and animals. In this work, we analysed the antimicrobial and clonal profiles of 115 SDSE infection and colonization isolates of human and equine origin. PFGE revealed the spread of two main clusters: clone A (57.4 %) and clone A (26.1 %). Remarkably, two isolates from clone B obtained from human colonization cases displayed identical PFGE patterns to those of three equine infection isolates. In addition, multilocus sequence typing allocated these isolates to ST129 (CC31). All of the SDSE isolates were susceptible to penicillin, vancomycin, gentamicin, levofloxacin and chloramphenicol. Tetracycline and erythromycin resistance rates were 65.2 and 13.9 % respectively. Nevertheless, none of the isolates displaying sporadic PFGE patterns showed erythromycin resistance. The majority of erythromycin-resistant isolates from clone A had inducible resistance to macrolides, lincosamines and streptogramins B (iMLS B phenotype), which is associated with the presence of the ermA gene, whereas the resistant isolates from clone B showed the M phenotype, associated with the mefA gene. In conclusion, the data indicated that the analysed collection of SDSE isolates displayed a clonal structure and that the isolates found in human colonization cases could also be involved in equine infections. INTRODUCTIONStreptococcus dysgalactiae subsp. equisimilis (SDSE) has increasingly been recognized as the aetiological agent of several human invasive infections worldwide (Bruun et al., 2013;Sunaoshi et al., 2010;Takahashi et al., 2010Takahashi et al., , 2011Tsai et al., 2014). SDSE isolates are frequently classified as Lancefield group C or G. Comparative genomic analyses revealed that several commonly found group A streptococci virulence factors have also been detected in SDSE isolates, including C5a peptidase, M protein, glyceraldehyde 3-phosphate dehydrogenase, hyaluronidase, streptokinase, streptolysin O and streptolysin S, amongst others (Reissmann et al., 2012;Sunaoshi et al., 2010;Suzuki et al., 2011;Watanabe et al., 2013). Consequently, human infections related to SDSE resemble those associated with group A streptococci . These infections include pharyngitis, septic arthritis, pneumonia, bacteraemia, endocarditis, meningitis, streptococcal toxic shock-like syndrome, cellulitis and necrotizing fasciitis (Brandt & Spellerberg, 2009). Similar to group A streptococci, SDSE has also been linked to post-...

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The history of muscle biopsy dates back to 1860, when Duchenne first performed a biopsy on a patient with symptoms of myopathy (1) . Since then, the basic and clinical science of muscle and muscle disease has gone through three stages of development: the classical period, the modern stage and the molecular era.

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Acinetobacter baumannii has been associated with antimicrobial resistance and ability to form biofilms. Furthermore, its adherence to host cells is an important factor to the colonization process. Therefore, this study intended to identify some virulence factors that can explain the success of A. baumannii in causing nosocomial infections. We studied 92 A. baumannii isolates collected from hospitals in Rio de Janeiro, Brazil. Isolates were identified and the susceptibility to antimicrobials was determined. Oxacilinase type β-lactamase encoding genes were amplified by polymerase chain reaction, and genetic diversity was investigated by pulsed-field gel electrophoresis (PFGE). In addition, biofilm formation on polystyrene plates using crystal violet staining was quantified, and adherence to human cell lines was evaluated. Eighty-six isolates were multidrug-resistant, of which 93% were carbapenem-resistant. All isolates had the bla OXA-51 gene and 94% had the bla OXA-23 gene, other searched bla OXA genes were not detected. PFGE typing showed two predominant clones, and biofilm production was observed in 79% of isolates. A. baumannii isolates adhered better to HEp-2 cell compared with A-549 cell. Clones A, B, E, and F showed a significantly increased adherence to HEp-2 compared with adherence to A-549 cell. Our findings revealed that A. baumannii isolates had high frequencies of resistance to antimicrobial agents, ability to form biofilm, and capacity to adhere to HEp-2 cells.