Search results for "Staphylococcus aureu"
showing 10 items of 298 documents
Development and characterization of essential oil component-based polymer films: a potential approach to reduce bacterial biofilm
2013
The development of new polymeric materials aimed to control the bacterial biofilm appears to be an important practical approach. The goal of the present study was to prepare and characterize poly(ethylene-co-vinyl acetate) copolymer (EVA) films containing citronellol, eugenol, and linalool and evaluate their efficiency on growth and biofilm formation of Listeria monocytogenes, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa in monospecies and dual species. The results showed that the addition of oil components influenced the elastic modulus (15 % decrease), the tensile stress (30 % decrease), the elongation at break (10 % increase), and the co…
Relationships between Staphylococcus aureus genetic background, virulence factors, agr groups (alleles), and human disease
2002
ABSTRACT The expression of most Staphylococcus aureus virulence factors is controlled by the agr locus, which encodes a two-component signaling pathway whose activating ligand is an agr -encoded autoinducing peptide (AIP). A polymorphism in the amino acid sequence of the AIP and of its corresponding receptor divides S. aureus strains into four major groups. Within a given group, each strain produces a peptide that can activate the agr response in the other member strains, whereas the AIPs belonging to different groups are usually mutually inhibitory. We investigated a possible relationship between agr groups and human S. aureus disease by studying 198 S. aureus strains isolated from 14 asym…
Impact de la modulation de la réponse inflammatoire pulmonaire et systémique de l'hôte mediée par Toll-Like Receptor 2 dans un modèle animal de pneum…
2012
EA MERS Hors CT hors EJ; Master
Stafilococchi: causa di mastite
2011
Staphylococcus aureus è un batterio che può provocare mastite. Negli ultimi anni sono stati isolati Stafilococchi resistenti a molti degli antibiotici usati in terapia. Il presente lavoro ha lo scopo di caratterizzare gli Stafilococchi circolanti in Sicilia per prevenire la diffusione di batteri patogeni resistenti
Ceļa locītavas septiska artrīta ārstēšanas rezultāti
2015
Pasaulē nav vienotas taktikas ceļa locītavas septiska artrīta ārstēšanai. Ir vairāki protokoli, kuros pie septiska artrīta izvēlas punktēt ceļa locītavu, tādējādi nodrošinot drenāžu. Cits protokols paredz artroskopisku skalošanu vairākas reizes, neuzrādot konkrētu skaitu. Ja augstāk minētās darbības kopā ar antibakteriālu terapiju nedod vēlamo efektu, dažkārt tiek veikta vaļēja sinovektomija vai pat locītavas endoprotezēšana. Traumatoloģijas un ortopēdijas slimnīcā nav vienota protokola ceļa locītavas septiska artrīta ārstēšanai. Parasti cenšas 3 reizes izskalot ceļa locītavu ar troakāriem, izmantojot 6 litrus fizioloģiskā šķidruma. Tad tiek izvērtēti iekaisuma rādītāji dinamikā un lemts pa…
Inhibition of bacterial virulence factors of foodborne pathogens by paprika (Capsicum annuum L.) extracts
2022
Abstract Capsicum annuum extracts of different polarities were tested for their antimicrobial, antibiofilm, and anti-Quorum sensing (QS) activity against several pathogenic microorganisms and possible toxic effects using an in vivo model (Galleria mellonella L.). Hexane (HE) and Chloroform extract (CE) were the most active in inhibiting biofilm formation of the eight bacteria tested, with inhibition percentages between 22 and 88% for a concentration of 100 μg/mL. These extracts were potent inhibitors of Staphylococcus aureus biofilm, and microscopy analysis confirmed a significant reduction in adhered cells. Moreover, polystyrene surfaces coated with these extracts decreased Staph. aureus a…
ChemInform Abstract: One-Step Synthesis, Crystallographic Studies and Antimicrobial Activity of New 4-Diazopyrazole Derivatives.
2010
Summary A number of new 4-diazopyrazole derivatives were prepared by the reaction of 1- R -3-methyl-5(R 1 -substituted)benzamidopyrazoles with a sevenfold excess of nitrous acid in acetic medium. The compounds were tested for activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus faecalis, Listeria monocytogenes, Candida albicans, Candida tropicalis and Paecilomyces varioti . The highest microbial susceptibility was shown by Gram-positive bacteria, with minimum inhibitory concentrations (MIC) in the range 0.5–12.5 μg/mL. For S aureus the R 1 substituents were screened utilizing the Topliss operational scheme. The 4-nitro g…
Staphylococcus aureus alpha-toxin attack on human platelets promotes assembly of the prothrombinase complex.
1990
alpha-Toxin, the major cytolysin of Staphylococcus aureus, promotes blood coagulation by its attack on human platelets (Bhakdi S., Muhly, M., Mannhardt, U., Hugo, F., Klapettek, K., Mueller-Eckhardt, C., and Roka, L. (1988) J. Exp. Med. 168, 527-542). In the present study we demonstrate that toxin attack on gel-filtered human platelets initiates the assembly of prothrombinase complexes at rates up to 10-fold of controls. Treatment of platelets with 0.1 microgram/ml alpha-toxin resulted in generation of 1.4 units of thrombin/10(8) platelets. A similar rate of thrombin generation was noted when platelets were subjected to three cycles of freezing and thawing. However, the alpha-toxin-induced …
Antimicrobial and antistaphylococcal biofilm activity from the sea urchin Paracentrotus lividus
2010
Aims: Staphylococcal biofilm-associated infections are resistant to conventional antibiotics. Consequently, new agents are needed to treat them. With this aim, we focused on the effector cells (coelomocytes) of the sea urchin Paracentrotus lividus immune system. Methods and Results: We tested the activity of the 5-kDa peptide fraction of the cytosol from coelomocytes (5-CC) against a group of Gram-positive, Gram-negative bacteria and fungi. We determined minimal inhibitory concentrations (MICs) ranging from 253·7 to 15·8 mg ml−1. We observed an inhibitory activity and antibiofilm properties of 5-CC against staphylococcal biofilms of reference strains Staphylococcus epidermidis DSM 3269 an…
MRSA ST22-IVa (EMRSA-15 clone) in Palermo, Italy
2010
Summary: Epidemic spread of methicillin-resistant Staphylococcus aureus (MRSA) strains carrying the Staphylococcal Chromosomal Cassettes (SCC) mec type IV is being increasingly reported in many geographical areas. A survey to determine the prevalence and characteristics of MRSA SCCmec IV isolates identified in four general hospitals in Palermo, Italy, was carried out. During the period February–June 2009, SCCmec type IVa has been found in 12 out of 94 isolates. Nine isolates from all hospitals and all strains from a NICU outbreak occurring in the same period were attributed with the ST22-IVa (EMRSA-15) clone. In our setting, due to the changing MRSA epidemiology, detection of SCCmec IV coul…