Antibiotic Resistance and Presence of Persister Cells in the Biofilm-like Environments in .

This study investigated antibiotic resistance and presence of persister cells in strains belonging to capsular types Ia/ST-103, III/ST-17, and V/ST-26 in biofilm-like environments. strains were susceptible to penicillin, clindamycin, and erythromycin. Resistance genes were associated with M (80%), O (20%), B (80%), and B (40%).

Molecular characterization, antimicrobial resistance and invasion of epithelial cells by Streptococcus agalactiae strains isolated from colonized pregnant women and newborns in Rio de Janeiro, Brazil.

Aims: To evaluate the prevalence, molecular characteristics, antimicrobial susceptibility, and epithelial invasion of Streptococcus agalactiae strains isolated from pregnant women and newborns in Rio de Janeiro, Brazil.

Methods And Results: A total of 67 S. agalactiae isolates, 48 isolates from pregnant women and 19 from neonates, were analyzed.

RdJ detection tests to identify a unique MRSA clone of ST105-SCCII lineage and its variants disseminated in the metropolitan region of Rio de Janeiro.

Hospital bloodstream infection (BSI) caused by methicillin-resistant (MRSA) is a major cause of morbidity and mortality and is frequently related to invasive procedures and medically complex patients. An important feature of MRSA is the clonal structure of its population. Specific MRSA clones may differ in their pathogenic, epidemiological, and antimicrobial resistance profiles.

Lineage ST62/87: The International Spread of This Potentially Invasive Lineage.

is known to be associated with a variety of infections, from pharyngitis to necrotizing fasciitis (flesh-eating disease). of the ST62/87 lineage is recognized as one of the most frequently isolated lineages of invasive infections caused by this bacterium, which may be involved in hospital outbreaks and cluster infections. Despite this, comparative genomic and phylogenomic studies have not yet been carried out for this lineage.

High frequency of increased triclosan MIC among CC5 MRSA and risk of misclassification of the SCCmec into types.

Background: Typing of staphylococcal cassette chromosome mec (SCCmec) elements is commonly used for studies on the molecular epidemiology of MRSA.

Objectives: To perform an investigation centred on uncovering the reasons for misclassification of MRSA clonal complex 5 (CC5) SCCmec type II clinical isolates in our laboratory.

Methods: MRSA isolates from CC5 were subjected to WGS and SCCmec typing.

Assessing and biofilm development by subsp. using a murine model of catheter-associated biofilm and human keratinocyte cell.

subsp. (SDSD) is an important agent of bovine mastitis. This infection causes an inflammatory reaction in udder tissue, being the most important disease-causing significant impact on the dairy industry.

Cellular Growth Arrest and Efflux Pumps Are Associated With Antibiotic Persisters in Induced in Biofilm-Like Environments.

(group A -GAS) is an important pathogen for humans. GAS has been associated with severe and invasive diseases. Despite the fact that these bacteria remain universally susceptible to penicillin, therapeutic failures have been reported in some GAS infections.

Ciprofloxacin-Resistant Kerstersia gyiorum Isolated From a Chronic Wound in Brazil: A Case Report.

Unlabelled: The presence of Kerstersia gyiorum in lower leg wounds has been reported in case studies from several countries.

Objective: This study evaluated the antimicrobial susceptibility profile of K gyiorum isolated from a chronic wound.

Methods: An 85-year-old woman with chronic venous insufficiency presented to an intermediate care unit in Niteroi City, Rio de Janeiro, Brazil, with an instep chronic wound of 14 cm² with wound duration of 6 months.

Low lineage diversity and increased virulence of group C subsp. .

In some species, the population structure of pathogenic bacteria is clonal. However, the mechanisms that determine the predominance and persistence of specific bacterial lineages of group C remain poorly understood. In Brazil, a previous study revealed the predominance of two main lineages of subsp.

Biofilm development and computational screening for new putative inhibitors of a homolog of the regulatory protein BrpA in Streptococcus dysgalactiae subsp. dysgalactiae.

Streptococcus dysgalactiae subsp. dysgalactiae (SDSD), a Lancefield group C streptococci (GCS), is a frequent cause of bovine mastitis. This highly prevalent disease is the costliest in dairy industry.

Monitoring and Molecular Characterization of Staphylococcus aureus Isolated from Chronic Wounds.

Objective: Researchers analyzed chronic wounds treated with 2% hydrogel to determine whether the presence of methicillin-resistant Staphylococcus aureus (MRSA) is related to the presence of clinical signs of infection.

Methods: Thirty-five patients were recruited for this descriptive study using a quantitative approach. Staphylococcus aureus was identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

A unique SaeS allele overrides cell-density dependent expression of saeR and lukSF-PV in the ST30-SCCmecIV lineage of CA-MRSA.

ST30 (CC30)-SCCmec IV (USA1100) is one of the most common community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) lineages. ST30 isolates typically carry lukSF-PV genes encoding the Panton-Valentine leukocidin (PVL) and are responsible for outbreaks of invasive infections worldwide. In this study, twenty CC30 isolates were analyzed.

Assessment and characterization of biofilm formation among human isolates of Streptococcus dysgalactiae subsp. equisimilis.

The capacity to form biofilm is considered a protective mechanism that allows the bacteria to survive and proliferate in hostile environments, facilitating the maintenance of the infectious process. Recently, biofilm has become a topic of interest in the study of the human pathogen group A Streptococcus (GAS). Although GAS has not been associated with infection on medical implants, the presence of microcolonies embedded in an extracellular matrix on infected tissues has been reported.

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.

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.

Impact of biocides on biofilm formation by methicillin-resistant Staphylococcus aureus (ST239-SCCmecIII) isolates.

Procedures of sterilization and disinfection are essential to ensure that medical and surgical instruments will not transmit infectious pathogens to patients. In the present paper, we tested the residual effect of these compounds on biofilm formation and its efficiency in disrupting preformed biofilms using methicillin-resistant Staphylococcus aureus (MRSA) isolates of the lineage ST239-SCCmecIII. All compounds examined, except 70% alcohol, caused a significant impairment in biofilm formation with concomitant inhibition of cell growth.

Comparison of different methods for detecting methicillin resistance in MRSA isolates belonging to international lineages commonly isolated in the American continent.

The aim of the present paper was to compare different methods for detecting methicillin resistance in Staphylococcus aureus. Among the isolates analyzed, 52 belonged to MRSA international lineages commonly detected in the American continent and 14 to sporadic MRSA clones. Both 30 microg-cefoxitin disk and PBP2a had 100% sensibility/specificity when the low-level heterogeneous isolates were tested and, thus, are highly recommended.

agr RNAIII divergently regulates glucose-induced biofilm formation in clinical isolates of Staphylococcus aureus.

Staphylococcus aureus is an important nosocomial and community-acquired pathogen. Hospital infections are frequently complicated by the ability of bacteria to form biofilms on different surfaces. The development of bacterial films on medical indwelling devices, such as prostheses, often requires surgical procedures to remove the contaminated implant.

Detection and characterization of international community-acquired infections by methicillin-resistant Staphylococcus aureus clones in Rio de Janeiro and Porto Alegre cities causing both community- and hospital-associated diseases.

Community-acquired infections by methicillin-resistant Staphylococcus aureus (CA-MRSA) in the absence of classic risk factors for MRSA diseases have been reported in different continents. In the article presented here, using molecular typing methods as pulsed-field gel electrophoresis, staphylococcal cassette chromosome mec typing, and multilocus sequence typing, we characterized CA-MRSA isolates from Rio Janeiro and Porto Alegre. The results indicated the presence of international CA-MRSA clones in these 2 Brazilian cities.

Commensal isolates of methicillin-resistant Staphylococcus epidermidis are also well equipped to produce biofilm on polystyrene surfaces.

Objectives: To study biofilm production and to detect icaAD, atlE and aap genes in 137 isolates of methicillin-resistant Staphylococcus epidermidis (MRSE) obtained from healthy individuals from the community (35 isolates), from hospitalized patients at the Antônio Pedro University Hospital (25 isolates) and from individuals from a home-care system (HCS; 77 isolates).

Methods: Biofilm production was determined in vitro using polystyrene inert surfaces. icaAD, atlE and aap genes were detected using PCR.

The predominant variant of the Brazilian epidemic clonal complex of methicillin-resistant Staphylococcus aureus has an enhanced ability to produce biofilm and to adhere to and invade airway epithelial cells.

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a therapeutic problem. In the present study, the molecular characterization by pulsed-field gel electrophoresis of MRSA isolates collected from a university hospital revealed that the predominant variant of the Brazilian epidemic clonal complex (BECC) was responsible for the increase in the incidence of MRSA strains, which reached 28% in 1998. It was verified that this predominant variant of the BECC displayed an enhanced ability to produce biofilm on inert polystyrene surfaces and to adhere to and invade epithelial airway cells.

First report of infection with community-acquired methicillin-resistant Staphylococcus aureus in South America.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has recently emerged in the southwestern Pacific, North America, and Europe. These S. aureus isolates frequently shared some genetic characteristics, including the SCCmec type IV and lukS-lukF genes.

Antimicrobial susceptibility patterns and genomic diversity in strains of Streptococcus pyogenes isolated in 1978-1997 in different Brazilian cities.

Penicillin has been the antimicrobial of choice for the treatment of Streptococcus pyogenes infections for almost six decades. Although penicillin-resistant isolates have not been described to date, clinical failures have been reported after treatment with beta-lactams. In this study, we analysed the antimicrobial susceptibility and genetic diversity of S.

Isolation of methicillin-resistant coagulase-negative staphylococci from patients undergoing continuous ambulatory peritoneal dialysis (CAPD) and comparison of different molecular techniques for discriminating isolates of Staphylococcus epidermidis.

Coagulase-negative staphylococci (CNS) have emerged as an important pathogen in nosocomial infections. About 80%-90% of CNS isolates associated with hospital infections are methicillin-resistant coagulase-negative staphylococci (MRCNS). The aims of this study were to screen for MRCNS isolates in the flora of a small population of patients undergoing continuous ambulatory peritoneal dialysis (CAPD) and to evaluate the discriminatory power of different molecular methods: pulsed-field gel electrophoresis (PFGE), mecA location, ClaI/mecA polymorphism and arbitrarily primed polymerase chain reaction (AP-PCR) for characterizing isolates of methicillin-resistant Staphylococcus epidermidis (MRSE).

Analysis of different molecular methods for typing methicillin-resistant Staphylococcus aureus isolates belonging to the Brazilian epidemic clone.

The extensive geographic spread of MRSA isolates belonging to the Brazilian epidemic clone (BEC) limited the value of pulsed-field gel electrophoresis (PFGE) in epidemiological studies of outbreaks caused by these strains. Thus, the discriminatory power of eight different molecular methods was evaluated in an attempt to establish a methodology for genotyping BEC isolates involved in intra-hospital outbreaks. BEC isolates from five hospitals in Teresina City, Piaui State were genotyped by conventional electrophoresis or PFGE of Cla I- or Sma I-digested genomic DNA hybridised with specific labelled mecA, Tn554, IS257 and IS256 probes.