Search results for "(Staphylococcus aureus)"
showing 10 items of 294 documents
Staphylococcus aureus nēsāšana veselu cilvēku starpā
2016
Staphylococcus aureus bieži vien kolonizē nāsis, padarot veselu cilvēku par šo patogēno mikroorganismu nēsātāju. Medicīnas darbiniekiem un medicīnas studentiem, kas ir pakļauti ilgu laika periodu slimnīcas videi, ir lielākais risks kļūt par S.aureus nēsātāju. Nēsātāji darbojas kā pastāvīgi infekcijas avoti. Stafilokoku infekcijas visbiežāk attīstās imūn-novājinātiem pacientiem, tāpēc nēsāšana medicīnas darbinieku vidū ir sevišķi svarīga. Darba mērķis: noteikt S.aureus nēsāšanas biežumu medicīnas fakultātes studentu vidū. Galvenie uzdevumi: 1.Noteikt S.aureus nēsāšanas atkarību no medicīnas fakultātes kursa ( otrais kurss, sestais kurss) – tātad no saskares ar slimnīcas vidi. 2.Noteikt S.aur…
Control of biofilm formation by poly-ethylene-co-vinyl acetate films incorporating nisin.
2010
The aim of this study was to evaluate the effect of poly-ethylene-co-vinyl acetate (EVA) films incorporating different concentrations (0.1%, 0.5% and 1%) of nisin on the biofilm-forming ability of Listeria monocytogenes ATCC 7644, Staphylococcus aureus 815 and Staphylococ-cus epidermidis ATCC 35984. Nisin was incorporated into two grades of EVA (EVA14 and EVA28) in the melt during a common film-blowing operation. The efficacy of EVA/nisin films was evaluated by biofilm biomass measurements and Live/Dead staining in combination with fluorescence microscopy. In order to evaluate whether the nisin incorporation could modify the film surface properties, contact angle measurements and scanning e…
Antibacterial Activity of Flavonoids Against Methicillin-resistant Staphylococcus aureus strains
2000
An experimental and theoretical study was performed on the anti-staphylococcal activity of 18 natural and synthetic flavonoids against methicillin-resistant Staphylococcus aureus strains. The analysed flavonoids belong to three well-differentiated structural patterns: chalcones, flavanones and flavones. The quantitative analysis of the anti-staphylococcal activity of the compounds was carried out by determining their percent inhibition degree. The hierarchical cluster analysis method was used to analyse the anti-MRSA activity of the compounds. With this methodology, the flavonoids were classified into four groups according to their anti-staphylococcal activity (high, sufficient, intermediat…
A Superantigen as Virulence Factor in an Acute Bacterial Infection
1994
This study addresses the role of a bacterial superantigen as a potential virulence factor during an acute systemic infection. BALB/c mice were intravenously infected with a recombinant Staphylococcus aureus strain capable of producing plasmid-encoded staphylococcal enterotoxin B (SEB) or with the SEB plasmid-deficient parental strain. Infection with SEB-producing bacteria resulted in an initial expansion and subsequent decrease of circulating V beta 8+ T lymphocytes. This numeric decrease was accompanied by a SEB-specific state of hyporesponsiveness of splenic T cells. In parallel with SEB-triggered unresponsiveness of a large proportion of T lymphocytes, a weakening of the overall T cell r…
Antimicrobial Effects Of The Ethanolic Extracts And Essential Oils Of Tanacetum Vulgare L From Romania
2015
Abstract This paper investigates the antimicrobial action of the extracts and essential oil of wildgrowing Tanacetum vulgare L on: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacilus subtilis, using the diffusion disc method. The essential oils but also the ethanolic extracts tested exhibited moderate action on Staphilococcus aureus and Bacillus subtilis and low action on E. coli and Pseudomonas aeruginosa. The moderate antimicrobial activity is related to the amount of some chemical components of the essential oil of T. vulgare flos. Thus, this paper presents also the quantitative and qualitative analysis of the essential oils of T. vulgare harvested from two differ…
Evaluation of dermal toxicity of antibacterial cotton textile coated by sol-gel technology
2017
AbstractThis paper reports about cotton textile modification by sol-gel technology with the purpose of obtaining antibacterial properties, evaluation of antibacterial properties and dermal toxicity tests of cotton textile with Zn and Si coating. Antibacterial properties evaluation against pathogenic microorganisms Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli made using the Parallel streak method in accordance with ATCC147 standard. For more specific evaluation of the coated textile, in vitro cytotoxicity test with epidermal HaCat cells was done. It is concluded that the coatings containing Zn and Si obtained by the sol-gel technology can impart antibacterial propertie…
Assessment of the antioxidant and antibacterial activities of different olive processing wastewaters.
2017
Olive processing wastewaters (OPW), namely olive mill wastewater (OMW) and table-olive wastewaters (TOW) were evaluated for their antibacterial activity against five Gram-positive and two Gram-negative bacteria using the standard disc diffusion and thin layer chromatography (TLC)-bioautography assays. Disc diffusion screening and bioautography of OMW were compared to the phenolic extracts of table-olive brines. Positive activity against S. aureus was demonstrated. The optimization of chromatographic separation revealed that hexane/acetone in the ratio of 4:6 was the most effective for phenolic compounds separation. A HPLC-MS analysis was performed showing that only two compounds, hydroxytyr…
Solid Lipid Nanoparticles Containing Vancomycin
2007
Staphylococci coagulase-negative and Staphylococcus aureus are the most common cause of nosocomial infections and can induce a wide spectrum of diseases associated with remarkable morbidity and mortality. Biofilms of staphylococci are intrinsically resistant to conventional antibiotics and, being commonly associated with implanted medical device, such as catheters and vascular grafts, have the potential to cause blood-stream infections. In recent years increasing attention has been addressed to Solid Lipid Nanoparticles (SLNs), thanks to their biodegradability and ability to entrap a variety of biologically active compounds, in the area of modified drug delivery technology in the attempt to…
Staphylococcus aureus alpha toxin mediates polymorphonuclear leukocyte-induced vasocontraction and endothelial dysfunction.
2002
The effect of Staphylococcus aureus alpha toxin (alpha-toxin) on selectin-mediated neutrophil adhesion was investigated in polymorphonuclear leukocyte- (PMN) induced vasocontraction and endothelial dysfunction. Adherence of human PMNs to rat aortic endothelium increased significantly following stimulation of the endothelium with alpha-toxin (0.1, 0.5, and 1 microg/mL). This effect could be significantly attenuated by monoclonal antibodies directed against P-selectin or fucoidin, a carbohydrate known to block selectins. Unstimulated human PMNs (10(6)cells/mL) were added to organ chambers containing rat aortic rings stimulated with alpha-toxin (0.5 microg/mL). PMNs elicited a significant vaso…
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…