Publications by authors named "Guelguen Bosgelmez-Tinaz"

In this study, two-layer poly(vinyl alcohol)/gelatin (PVA/GEL) nanofiber patches containing cinnamaldehyde (CA) in the first layer and gentamicin (GEN) in the second layer were produced by the electrospinning method. The morphology, chemical structures, and thermal temperatures of the produced pure (PVA/GEL), CA-loaded (PVA/GEL/CA), GEN-loaded (PVA/GEL/GEN), and combined drug-loaded (PVA/GEL/CA/GEN) nanofiber patches were determined by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and differential scanning calorimetry, respectively. Their mechanical properties, swelling and degradation behavior, and drug release kinetics were investigated.

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To investigate the hypothesis that zeolites interfere with quorum-sensing (QS) systems of and by adsorbing -acyl homoserine lactone (AHL) signal molecules. QS inhibition by zeolite 4A was investigated using an AHL-based bioreporter assay. The adsorption of the AHLs was evaluated by performing inductively coupled plasma-optical emission spectroscopy and confirmed by Monte Carlo and molecular dynamic simulations.

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Aims: Quorum sensing (QS) is a cell-cell communication system used by a broad spectrum of pathogenic bacteria to control the expression of their virulence genes. The interruption of QS systems of pathogenic bacteria has been considered as a novel way to fight bacterial diseases. In this study, trans-anethole, the main component of anise (Pimpinella anisum) oil was examined for its QS inhibitor (QSI) potential in an attempt to identify novel QSI compound effective against opportunistic pathogen Pseudomonas aeruginosa.

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Antibiotics are commonly used for the treatment of microbial infections. With the widespread appearance of multi antibiotic-resistant bacteria, it is becoming increasingly more difficult to treat bacterial infections with conventional antibiotics. Thus, there is an increasing need for new strategies to cope with infectious diseases.

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Introduction: In the opportunistic pathogen Pseudomonas aeruginosa, the production of several virulence factors depends on quorum sensing (QS) involving N-acylhomoserine lactone signal molecules. In vitro studies have suggested that the QS system is crucial in the pathogenesis of P. aeruginosa.

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Antibiotics are commonly used to treat microbial infections. Due to misuse or large-scale use of antibiotics, many pathogens have gained resistance which makes antibiotic treatments ineffective. The discovery that many bacteria use quorum sensing (QS) to regulate their virulence factor and pathogenicity production makes the QS system an attractive target for antimicrobial therapy.

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The antioxidant and antibacterial activities, and total phenolic contents of Rosa damascena Mill. flower extracts (absolute, essential oil and hydrosol) were investigated. The chemical compositions of these extracts were analysed by GC-MS.

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Objective: To determine grlA and gyrA mutations in ciprofloxacin- methicillin-resistant Staphylococcus aureus isolates and their susceptibility to current antimicrobials, including a newer fluoroquinolone gatifloxacin, glycopeptides vancomycin, teicoplanin and oxazolidinone linezolid.

Methods: A total of 56 methicillin-resistant S. aureus (MRSA) isolates were collected during 2003-2006 from inpatients of Süleyman Demirel University Hospital.

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In the opportunistic pathogen Pseudomonas aeruginosa, the production of several virulence factors such as elastase, rhamnolipids and pyocyanin depends on cell-to-cell signaling or quorum sensing (QS) involving N-acylhomoserine lactone (AHL) signal molecules. In vitro studies with laboratory strains and virulence studies in animals with these same strains have demonstrated the contribution of QS to the pathogenesis of P. aeruginosa.

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Many Gram-negative bacteria use N-acyl homoserine lactone signal molecules to monitor their own population density and coordinate gene regulation in a process called quorum sensing (QS). Increasing evidence implies that certain eukaryotes produce QS-inhibitory compounds. In this work, we tested 46 terrestrial plants materials for their ability to inhibit QS-regulated behaviors in different bacterial species.

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Acylated homoserine lactones (AHLs) are self-generated diffusible signal molecules that mediate population density dependent gene expression (quorum sensing) in a variety of Gram-negative bacteria, and several virulence genes of human pathogens are known to be controlled by AHLs. In this study, strains of Pseudomonas aeruginosa, Acinetobacter baumannii, Escherichia coli and Klebsiella pneumoniae, isolated from intensive care patients, were screened for AHL production by using AHL responsive indicator strains of Chromobacterium violaceum CV026 and Agrobacterium tumefaciens NT1. Positive reactions were recorded for all 50 isolates of P.

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