The survival of epidemic and sporadic MRSA on human skin mimics is determined by both host and bacterial factors.

Bacterial survival on, and interactions with, human skin may explain the epidemiological success of MRSA strains. We evaluated the bacterial counts for 27 epidemic and 31 sporadic MRSA strains on 3D epidermal models based on N/TERT cells (NEMs) after 1, 2 and 8 days. In addition, the expression of antimicrobial peptides (hBD-2, RNase 7), inflammatory cytokines (IL-1, IL-6) and chemokine IL-8 by NEMs was assessed using immunoassays and the expression of 43 virulence factors was determined by a multiplex competitive Luminex assay.

Real time monitoring of Staphylococcus aureus biofilm sensitivity towards antibiotics with isothermal microcalorimetry.

Biofilm-associated infections with Staphylococcus aureus are difficult to treat even after administration of antibiotics that according to the standard susceptibility assays are effective. Currently, the assays used in the clinical laboratories to determine the sensitivity of S. aureus towards antibiotics are not representing the behaviour of biofilm-associated S.

Paracetamol modulates biofilm formation in Staphylococcus aureus clonal complex 8 strains.

Staphylococcus aureus biofilms are a major problem in modern healthcare due to their resistance to immune system defenses and antibiotic treatments. Certain analgesic agents are able to modulate S. aureus biofilm formation, but currently no evidence exists if paracetamol, often combined with antibiotic treatment, also has this effect.

During the Early Stages of Staphylococcus aureus Biofilm Formation, Induced Neutrophil Extracellular Traps Are Degraded by Autologous Thermonuclease.

extracellular DNA (eDNA) plays a crucial role in the structural stability of biofilms during bacterial colonization; on the contrary, host immune responses can be induced by bacterial eDNA. Previously, we observed production of thermonuclease during the early stages of biofilm formation in a mammalian cell culture medium. Using a fluorescence resonance energy transfer (FRET)-based assay, we detected thermonuclease activity of biofilms grown in Iscove's modified Dulbecco's medium (IMDM) earlier than that of widely studied biofilms grown in tryptic soy broth (TSB).

Production of Staphylococcal Complement Inhibitor (SCIN) and Other Immune Modulators during the Early Stages of Staphylococcus aureus Biofilm Formation in a Mammalian Cell Culture Medium.

Immune modulators are known to be produced by matured biofilms and during different stages of planktonic growth of Little is known about immune modulator production during the early stages of biofilm formation, thus raising the following question: how does protect itself from the innate immune responses at these stages? Therefore, we determined the production of the following immune modulators: chemotaxis inhibitory protein of staphylococci (CHIPS); staphylococcal complement inhibitor (SCIN); formyl peptide receptor-like 1 inhibitor; gamma-hemolysin component B; leukocidins D, E, and S; staphylococcal superantigen-like proteins 1, 3, 5, and 9; and staphylococcal enterotoxin A. Production was determined during biofilm formation in Iscove's modified Dulbecco's medium at different time points using a competitive Luminex assay and mass spectrometry. Both methods demonstrated the production of the immune modulators SCIN and CHIPS during the early stages of biofilm formation.

Protein A Is a Key Factor in Neutrophil Extracellular Traps Formation.

are strong inducers of neutrophil extracellular traps (NETs), a defense mechanism of neutrophils against pathogens. Our aim was to explore the role of Protein A in -induced NETosis. We determined the Protein A production of four different strains and found a direct relationship between the degree of NETosis induction and Protein A production: strains producing higher concentrations of Protein A evoke significantly more NETs.

IgG4 subclass-specific responses to Staphylococcus aureus antigens shed new light on host-pathogen interaction.

IgG4 responses are considered indicative for long-term or repeated exposure to particular antigens. Therefore, studying IgG4-specific antibody responses against Staphylococcus aureus might generate new insights into the respective host-pathogen interactions and the microbial virulence factors involved. Using a bead-based flow cytometry assay, we determined total IgG (IgGt), IgG1, and IgG4 antibody responses to 40 different S.

Faecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae among humans in Java, Indonesia, in 2001-2002.

Objective: To characterise commensal Escherichia coli and other Enterobacteriaceae with reduced susceptibility to cefotaxime that were collected in a large survey carried out among 3995 patients and healthy persons in two urban regions on Java, Indonesia, in 2001-2002.

Methods: The putative extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae were analysed using double-disk synergy tests, isoelectric focusing, PCR assays, DNA sequencing, and pulsed-field gel electrophoresis (PFGE).

Results: On the day of discharge after five or more days of hospitalisation, at least 95 of 999 (9.

Rapid typing of extended-spectrum β-lactamase- and carbapenemase-producing Escherichia coli and Klebsiella pneumoniae isolates by use of SpectraCell RA.

Enterobacteriaceae are important pathogens of both nosocomial and community-acquired infections. In particular, strains with broad-spectrum beta-lactamases increasingly cause problems in health care settings. Rapid and reliable typing systems are key tools to identify transmission, so that targeted infection control measures can be taken.

Molecular characterization of extended-spectrum beta-lactamases in clinical Escherichia coli and Klebsiella pneumoniae isolates from Surabaya, Indonesia.

Background: No detailed reports regarding extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae are currently available from Indonesia, the fourth most populous country in the world.

Methods: A survey was carried out to investigate the molecular epidemiology and genetic characteristics of clinical ESBL-producing Escherichia coli and Klebsiella pneumoniae isolates originating from the Dr. Soetomo Academic Hospital in Surabaya, Indonesia, over a 4 month period (January to April 2005).

Methicillin-resistant Staphylococcus aureus in meat products, the Netherlands.

A new methicillin-resistant Staphylococcus aureus (MRSA) clone related to pig and cattle farming was detected in the Netherlands. We investigated the extent of S. aureus presence in meat and found 36 S.

The role of human innate immune factors in nasal colonization by Staphylococcus aureus.

Staphylococcus aureus colonization of the human nares predisposes to sometimes severe auto-infection. To investigate whether genetic polymorphism affects the S. aureus carriage status, sequence variation in alpha-defensin and beta-defensin, and mannose-binding lectin (MBL) genes were determined for a group of volunteers (n=109) with known S.

Microevolution in genomic short sequence repeats of Candida albicans in non-neutropenic patients.

The genome of the yeast Candida albicans harbours many genomic short sequence repeats (SSRs). These are stable upon transition of colonization to infection in immune-compromised patients. We show here that in non-neutropenic patients this transition may coincide with variation in several of the SSRs.