Chemiluminescence of enterococci isolates from freshwater

André, Philippe; Metzger, Catherine; Petey, Sophie; Müller, Daniel; Vidon, Dominique J.-M.

doi:10.1016/j.femsle.2005.02.036

Cited by 4 publications

(4 citation statements)

References 32 publications

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“…The origin of the enterococci in the oral cavity is yet unclear. Some contend that most enterococci enter the oral cavity as contaminants derived from normal intestinal flora, whilst person to person translocation or transfer through water or contaminated food have been suggested by others [ 42 , 43 ]. Interestingly, a number of workers have surmised that antibiotic resistant enterococci in particular can be transmitted through contaminated food, leading to infections [ 43 , 44 ].…”

Section: Discussionmentioning

confidence: 99%

Enterococcus Species in the Oral Cavity: Prevalence, Virulence Factors and Antimicrobial Susceptibility

et al. 2016

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Enterococci are considered as transient constituent components of the oral microbiome that may cause a variety of oral and systemic infections. As there is sparse data on the oral enterococcal prevalence, we evaluated the Enterococcus spp. and their virulence attributes including antimicrobial resistance in a healthy Brazilian cohort. A total of 240 individuals in different age groups were studied (children 4–11 yrs, adolescents 12–17 yrs, young adults 18–29 yrs, adults 30–59 yrs, elderly over 60 yrs). Oral rinses were collected and isolates were identified by API 20 Strep and confirmed by 16S rDNA sequencing. E. faecalis isolates, in particular, were evaluated for virulence attributes such as their biofilm formation potential, and susceptibility to antimicrobials and an antiseptic, chlorhexidine gluconate. A total of 40 individuals (16.6%) and 10% children, 4% adolescents, 14% young adults, 30% adults, and 25% elderly carried oral enterococci. The oral enterococcal burden in adolescents was significantly lower than in the adults (p = 0.000) and elderly (p = 0.004). The proportion of carriers was higher among females (p = 0.001). E. faecalis was the most frequent isolate in all the age groups (p = 0.000), followed by E. durans and E. faecium. Whilst all the clinical isolates were able to form biofilms, only a proportion of them were able to produce lipase (92%), hemolysin (38%), and gelatinase (39%). Of all the isolates 53.8% were resistant to tetracycline, 12.3% to amoxicillin, 16.0% to ampicillin, 20.8% to chloramphenicol and 43.4% to erythromycin. None of the isolates were resistant to vancomycin. Our data suggest that in this Brazilian cohort the oral cavity may act as a significant reservoir of rather virulent and antibiotic resistant enterococci, with an increasing degree of carriage in the adults and elderly. Hence clinicians should be cognizant of this silent reservoir of virulent enterococci that may pose a particular threat of nosocomial infection.

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Section: Discussionmentioning

confidence: 99%

Enterococcus Species in the Oral Cavity: Prevalence, Virulence Factors and Antimicrobial Susceptibility

et al. 2016

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“…In total, 100 µL aliquots were stimulated with 10 µM Glu‐BSA for 5 min. ROS were immediately determined by a chemiluminescent assay as previously described (André et al ., 2005).…”

Section: Methodsmentioning

confidence: 99%

Advanced glycation end products (AGEs) activate mast cells

Sick¹,

Brehin²,

André³

et al. 2010

British J Pharmacology

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“…ROS measurements were performed every 15 min for 1 h, by measuring the relative light unit (RLU) signal at room temperature with a Lumac M-2500 Biocounter (Perstorp Analytical) after mixing 0.1 mL of 10 −4 M luminol (Sigma), 0.1 mL of 1.0 M sodium carbonate, and 0.1 mL of the bacterial suspension sampled from the well reactor, either with or without SOD. 29 Photon emission and the RLU signal were directly correlated to the ROS production since luminol was in excess. All samples were analyzed in triplicate to ensure the reproducibility of the method.…”

Section: Identification and Scavenger-helped Inhibition Of Ros Duringmentioning

confidence: 99%

On the use of capillary cytometry for assessing the bactericidal effect of TiO2. Identification and involvement of reactive oxygen species

Carré

Benhamida

Peluso

et al. 2013

Photochem Photobiol Sci

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The photocatalytic antimicrobial properties of TiO2 were studied on Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa bacterial strains taken as model strains for pathogenic species mainly implied in nosocomial infections. Capillary cytometry, coupled to a double-staining method for visualizing membrane integrity as a cell viability indicator, was highlighted as a rapid, easy-to-use, and automated numeration technique for quantitative and reproducible determination of cellular viability and thus, was able to give an accurate evaluation of the bactericidal effect of UV-A photocatalysis. Cytometry also enabled the study of TiO2-bacteria interactions and aggregation in the dark as well as TiO2 cytotoxicity. Compared with the traditional agar plate cultivation method, a significatively weaker reduction in cell viability was recorded by cytometry whatever the bacteria, TiO2 concentration, and duration of the photocatalytic treatment. The mismatch between both numeration methods was attributed to: (i) the presence of mixed bacteria-TiO2 aggregates that could interfere with bacteria measurement on plates, (ii) prolonged contact of the bacteria with TiO2 during incubation, which could cause additional cytotoxic damage to the bacterial wall, and (iii) the counting of viable but non-culturable bacteria as live bacteria in cytometry, whereas they cannot grow on solid media. A more pronounced difference was observed for P. aeruginosa and S. aureus bacteria, for which 2.9 and 1.9 log10 survival reduction overestimations were measured by plate counting, respectively. Using chemiluminescence, full restoration of cell viability by controlled addition of the O2˙(-) scavenger superoxide dismutase enzyme suggests that O2˙(-) acts, in our conditions, as the main reactive oxygen species responsible for the photocatalytic attack towards the targeted bacteria.

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Chemiluminescence of enterococci isolates from freshwater

Cited by 4 publications

References 32 publications

Enterococcus Species in the Oral Cavity: Prevalence, Virulence Factors and Antimicrobial Susceptibility

Enterococcus Species in the Oral Cavity: Prevalence, Virulence Factors and Antimicrobial Susceptibility

Advanced glycation end products (AGEs) activate mast cells

On the use of capillary cytometry for assessing the bactericidal effect of TiO2. Identification and involvement of reactive oxygen species

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