<b><i>Staphylococcus aureus</i></b> and Host Immunity in Recurrent Furunculosis

Abstract

Staphylococcus aureus is one of the severest and most persistent bacterial pathogens. The most frequent S. aureus infections include impetigo, folliculitis, furuncles, furunculosis, abscesses, hidradenitis suppurativa, and mastitis. S. aureus produces a great variety of cellular and extracellular factors responsible for its invasiveness and ability to cause pathological lesions. Their expression depends on the growth phase, environmental factors, and location of the infection. Susceptibility to staphylococcal infections is rooted in multiple mechanisms of host immune responses and reactions to bacterial colonization. Immunological and inflammatory processes of chronic furunculosis are based on the pathogenicity of S. aureus as well as innate and acquired immunity. In-depth knowledge about them may help to discover the whole pathomechanism of the disease and to develop effective therapeutic options. In this review, we focus on the S. aureus-host immune interactions in the pathogenesis of recurrent furunculosis according to the most recent experimental and clinical findings.

Phenotypic and genotypic virulence features of staphylococcal strains isolated from difficult-to-treat skin and soft tissue infections

“…Microbial strains were previously grown at 37˚C on nutrient agar. From the 24 hours bacterial culture a bacterial inoculum of McFarland 0.5 (1.5 x 10 8 CFU/ml) was prepared and was spot inoculated with a 10 μl sterile loop in Petri dishes with nutritive media containing the specific substratum for: haemolysins, PLOS ONE lecithinase, lipase, caseinase, gelatinase, esculinase, DN-ase, and amylase detection [28][29][30]. The strains were incubated for 24 hours at 37˚C, and at 25˚C for the next 48 hours to allow the production and observation of specific enzymatic virulence factors; their production being evaluated at 24, 48, and 72 hours incubation [28][29][30].…”

“…From the 24 hours bacterial culture a bacterial inoculum of McFarland 0.5 (1.5 x 10 8 CFU/ml) was prepared and was spot inoculated with a 10 μl sterile loop in Petri dishes with nutritive media containing the specific substratum for: haemolysins, PLOS ONE lecithinase, lipase, caseinase, gelatinase, esculinase, DN-ase, and amylase detection [28][29][30]. The strains were incubated for 24 hours at 37˚C, and at 25˚C for the next 48 hours to allow the production and observation of specific enzymatic virulence factors; their production being evaluated at 24, 48, and 72 hours incubation [28][29][30]. While soluble virulence factors secreted by bacteria are mainly associated with features of invasiveness, tissue destruction, and dissemination of infection, the development of biofilms are mainly associated with the persistence of infection, resistance, and tolerance to antimicrobials and host immune defense mechanisms.…”

“…For haemolysin production, the strains were spotted on 5% sheep blood agar and the aspect of the haemolytic zone surrounding the spot was noted [28][29][30]. For lecithinase and lipase production, the strains were spotted onto 2.5% yolk agar, and respectively on 1% Tween 80 agar, and afterwards the plates were incubated at 37˚C for 24 hours [28][29][30].…”

“…For haemolysin production, the strains were spotted on 5% sheep blood agar and the aspect of the haemolytic zone surrounding the spot was noted [28][29][30]. For lecithinase and lipase production, the strains were spotted onto 2.5% yolk agar, and respectively on 1% Tween 80 agar, and afterwards the plates were incubated at 37˚C for 24 hours [28][29][30]. An opaque (precipitation) zone surrounding the spot showed the lecithinase, respectively lipase production; a clear area can also appear around the spot in the lecithinase test [28][29][30].…”

Seasonality and multiannual variability of floods: case study from Eastern Poland

“…There are many different values of threshold level used. Some hydrologists use characteristic flows [2,5,[11][12][13] while others establish threshold level values as flows at certain probability of occurrence [9,[14][15][16][17]. According to recent research conducted in upper Wieprz river basin, the most suitable criterion, for environmental analysis, is value of flow occurrence exceeding 10% read from flow duration curve (FDC) (Q 10 ) [9,18].…”