11 documents found, page 1 of 2
Host soluble factors cause changes in Staphylococcus epidermidis antibiotic sus...
Oliveira, Fernando Eduardo Freitas; Gaio, Vânia Silva; Brás, Susana Maria Pereira; Oliveira, Sofia; França, Ângela Maria Oliveira SousaStaphylococcus epidermidis is a major nosocomial pathogen with a remarkable ability to adhere to the surfaces of indwelling medical devices and form biofilms. Unlike other nosocomial pathogens, the interaction of S. epidermidis with host factors has not been the focus of substantial research. This study aimed to assess the alterations in the antibiotic susceptibility and biofilm formation ability of S. epidermi...
Thymbra capitata essential oil has a significant antimicrobial activity against...
Almeida, Luciana; Lopes, Nathalie; Gaio, Vânia Silva; Cavaleiro, Carlos; Salgueiro, Lígia; Silva, Vanessa; Poeta, Patrícia; Cerca, NunoAbstract Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug-resistant opportunistic pathogen with a great ability to form biofilms. Herein, the antimicrobial potential of Thymbra capitata essential oil (EO) against MRSA biofilms was investigated. The determination of the minimum inhibitory concentration (MIC) and the minimum lethal concentration (MLC) of the T. capitata EO was first investigated ...
mazEF homologue has a minor role in Staphylococcus epidermidis 1457 virulence p...
Gaio, Vânia Silva; Lima, Tânia; Vilanova, Manuel; Cerca, Nuno; França, Ângela Maria Oliveira SousaStaphylococcus epidermidis biofilm cells are characterized by increased antimicrobial tolerance and improved ability to evade host immune system defenses. These features are, in part, due to the presence of viable but non-culturable (VBNC) cells. A previous study identified genes potentially involved in VBNC cells formation in S. epidermidis biofilms, among which SERP1682/1681 raised special interest due to the...
S. epidermidis putative toxin-antitoxin module mazEF: the role in VBNC formatio...
Gaio, Vânia SilvaStaphylococcus epidermidis é um microrganismo comensal que habita na pele e membranas mucosas dos seres humanos e outros mamíferos, mas que pode atuar como um agente patogénico oportunista, especialmente em pacientes imunocomprometidos e em bebés prematuros. Os principais fatores de virulência de S. epidermidis são a sua reduzida suscetibilidade a antibióticos e a sua capacidade de formação de biofilmes e de ev...
Virulence factors in coagulase-negative staphylococci
França, Ângela Maria Oliveira Sousa; Gaio, Vânia Silva; Lopes, Nathalie; Melo, Luís Daniel RodriguesCoagulase-negative staphylococci (CoNS) have emerged as major pathogens in healthcare-associated facilities, being S. epidermidis, S. haemolyticus and, more recently, S. lugdunensis, the most clinically relevant species. Despite being less virulent than the well-studied pathogen S. aureus, the number of CoNS strains sequenced is constantly increasing and, with that, the number of virulence factors identified in...
The putative toxin-antitoxin mazEF gene cluster is not involved in cell death i...
Gaio, Vânia Silva; Cerca, Nuno; França, Ângela Maria Oliveira SousaBackground: Toxin-antitoxin (TA) systems are known to work as a poison-antidote system, where the action of the antitoxin neutralizes the effect of the toxin counterpart. mazEF has been identified as a TA system in several species and is associated with the bacterial stress response. A previous study showed that the formation of viable but non-culturable (VBNC) cells in S. epidermidis biofilms might be linked t...
Biofilm released cells can easily be obtained in a fed-batch system using ica+ ...
Gaio, Vânia Silva; Cerca, NunoStaphylococcus epidermidis is one of the major opportunistic bacterial pathogens in healthcare facilities, mainly due to its strong ability to form biofilms in the surface of indwelling medical devices. To study biofilms under in vitro conditions, both fed-batch and flow systems are widely used, with the first being the most frequent due to their low cost and ease of use. Aim To assess if a fed-batch system pre...
Does mazEF have a role in S. epidermidis biofilm dormancy?
Gaio, Vânia Silva; França, Ângela Maria Oliveira Sousa; Cerca, NunoIntroduction: S. epidermidis is one of the main causes of nosocomial infections associated with the use of medical devices, due to its ubiquitous presence in human skin and mucosae and capacity to form biofilms. Biofilms are a major concern in healthcare systems, since they present higher antimicrobial tolerance and ability to evade host immune defenses, leading to recurrent and relapsing infections. Moreover, ...
Cells released from S. epidermidis biofilms present increased antibiotic tolera...
Gaio, Vânia Silva; Cerca, NunoBiofilm released cells (Brc) are thought to present an intermediary phenotype between biofilm and planktonic cells and this has the potential of affecting their antimicrobial tolerance. Aim Compare the antimicrobial tolerance profiles of Brc, planktonic or biofilm cultures of S. epidermidis. Methodology Planktonic, biofilm cultures or Brc from 11 isolates were exposed to peak serum concentrations (PSC) of antib...
Increased antibiotic tolerance to teicoplanin, vancomycin, rifampicin, erythrom...
Gaio, Vânia Silva; Cerca, NunoStaphylococcus epidermidis is a major etiological agent of nosocomial infections, mainly due to its ubiquitous presence in human skin and mucosae and ability to form biofilms, being recognized as a leader in hospital-acquired biofilm-associated infections. Since they are a great concern in healthcare systems, bacterial biofilms have been extensively studied over the years and their process of formation is frequ...