WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7150

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Now showing 1 - 10 of 10
  • Article
    Citation - WoS: 22
    Citation - Scopus: 23
    Bioactive Snail Mucus-Slime Extract Loaded Chitosan Scaffolds for Hard Tissue Regeneration: the Effect of Mucoadhesive and Antibacterial Extracts on Physical Characteristics and Bioactivity of Chitosan Matrix
    (IOP Publishing, 2021) Perpelek, Merve; Tamburacı, Sedef; Aydemir, Selma; Tıhmınlıoğlu, Funda; Baykara, Başak; Karakaşlı, Ahmet; Havıtçıoğlu, Hasan
    Biobased extracts comprise various bioactive components and they are widely used in tissue engineering applications to increase bioactivity as well as physical characteristics of biomaterials. Among animal sources, garden snail Helix aspersa has come into prominence with its antibacterial and regenerative extracts and show potential in tissue regeneration. Thus, in this study, bioactive H. aspersa extracts (slime, mucus) were loaded in chitosan (CHI) matrix to fabricate porous scaffolds for hard tissue regeneration. Physical, chemical properties, antimicrobial activity was determined as well as in vitro bioactivity for bone and cartilage regeneration. Mucus and slime incorporation enhanced mechanical properties and biodegradation rate of CHI matrix. Scanning electron microscopy images showed that the average pore size of the scaffolds decreased with higher extract content. Mucus and slime extracts showed antimicrobial effect on two bacterial strains. In vitro cytotoxicity, osteogenic and chondrogenic activity of the scaffolds were evaluated with Saos-2 and SW1353 cell lines in terms of Alkaline phosphatase activity, biomineralization, GAG, COMP and hydroxyproline content. Cell viability results showed that extracts had a proliferative effect on Saos-2 and SW1353 cells when compared to the control group. Mucus and slime extract loading increased osteogenic and chondrogenic activity. Thus, the bioactive extract loaded CHI scaffolds showed potential for bone and cartilage regeneration with enhanced physical properties and in vitro bioactivity.
  • Conference Object
    Citation - WoS: 16
    Thermal Characterization of Ag and Ag Plus N Ion Implanted Ultra-High Molecular Weight Polyethylene (uhmwpe)
    (Elsevier Ltd., 2007) Urkaç, Emel Sokullu; Oztarhan, A.; Tıhmınlıoğlu, Funda; Kaya, N.; Ila, D.; Muntele, C.; Tek, Z.
    Most of total hip joints are composed of ultra-high molecular weight polyethylene (UHMWPE). However, as ultra-high molecular weight polyethylene is too stable in a body, wear debris may accumulate and cause biological response such as bone absorption and loosening of prosthesis. In this study, ultra-high molecular weight polyethylene samples were Ag and Ag + N hybrid ion implanted by using MEVVA ion implantation technique to improve its surface properties. Samples were implanted with a fluence of 10(17) ion/cm(2) and extraction voltage of 30 kV. Implanted and unimplanted samples were investigated by thermo-gravimetry analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), optical microscopy (OM) and contact Angle measurement. Thermal characterization results showed that the ion bombardment induced an increase in the % crystallinity, onset and termination degradation temperatures of UHMWPE. (c) 2007 Elsevier B.V. All rights reserved.
  • Conference Object
    The Effect of Ag and Ag Plus N Ion Implantation on Cell Attachment Properties
    (American Institute of Physics, 2009) Urkaç, Emel Sokullu; Öztarhan, Ahmet; Tıhmınlıoğlu, Funda; Deliloğlu, İsmet Gürhan; İz, Sultan Gülce; Oks, Efim; Ila, Daryush
    Implanted biomedical prosthetic devices are intended to perform safely, reliably and effectively in the human body thus the materials used for orthopedic devices should have good biocompatibility. Ultra High Molecular Weight Poly Ethylene (UHMWPE) has been commonly used for total hip joint replacement because of its very good properties. In this work, UHMWPE samples were Ag and Ag+N ion implanted by using the Metal-Vapor Vacuum Arc (MEVVA) ion implantation technique. Samples were implanted with a fluency of 1017 ion/cm2 and extraction voltage of 30 kV. Rutherford Backscattering Spectrometry (RBS) was used for surface studies. RBS showed the presence of Ag and N on the surface. Cell attachment properties investigated with model cell lines (L929 mouse fibroblasts) to demonstrate that the effect of Ag and Ag+N ion implantation can favorably influence the surface of UHMWPE for biomedical applications. Scanning electron microscopy (SEM) was used to demonstrate the cell attachment on the surface. Study has shown that Ag+N ion implantation represents more effective cell attachment properties on the UHMWPE surfaces.
  • Conference Object
    Thermal Behaviour of W Plus C Ion Implanted Ultra High Molecular Weight Polyethylene (uhmwpe)
    (American Institute of Physics, 2009) Urkaç, Emel Sokullu; Öztarhan, Ahmet; Tıhmınlıoğlu, Funda; Ila, Daryush; Budak, S.; Chhay, B.; Nikolaev, A.
    The aim of this work was to examine thermal behavior of the surface modified Ultra High Molecular Weight Poly Ethylene (UHMWPE) in order to understand the effect of ion implantation on the properties of this polymer which is widely used especially for biomedical applications. UHMWPE samples were Tungsten and Carbon (W+C) hybrid ion implanted by using Metal Vapour Vacuum Arc (MEVVA) ion implantation technique with a fluence of 10 17 ions/cm2 and extraction voltage of 30kV. Untreated and surface-treated samples were investigated by Rutherford Back Scattering (RBS) Analysis, Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) Spectrometry, Thermo Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). This study has shown that ion implantation represents a powerful tool on modifying thermal properties of UHMWPE surfaces. This combination of properties can make implanted UHMWPE a preferred material for biomedical applications.
  • Conference Object
    Antimicrobial Activity of Essential Oils Against H. Pylori
    (John Wiley and Sons Inc., 2010) Altıok, Duygu; Bekmen, N.; Demiray Gürbüz, Ebru; Tıhmınlıoğlu, Funda; Yılmaz, Özlem
    [No abstract available]
  • Conference Object
    A Natural Antioxidant: Trans-Resveratrol Against H. Pylori
    (John Wiley and Sons Inc., 2010) Altıok, Duygu; Demiray Gürbüz, Ebru; Bekmen, N.; Tıhmınlıoğlu, Funda; Yılmaz, Özlem
    [No abstract available]
  • Conference Object
    Genipin Crosslinked Clarithromycin Loaded Chitosan Microspheres for Eradication of Helicobacter Pylori
    (John Wiley and Sons Inc., 2011) Altıok, Duygu; Demiray Gürbüz, Ebru; Bekmen, N.; Yılmaz, Özlem; Tıhmınlıoğlu, Funda
    [No abstract available]
  • Article
    Citation - WoS: 5
    Citation - Scopus: 7
    Effect of the Zeolite Filler on the Thermal Degradation Kinetics of Polypropylene
    (Scibulcom Ltd., 2006) Tıhmınlıoğlu, Funda; Pehlivan, Hilal; Balköse, Devrim; Ülkü, Semra
    In this study, the thermal degradation behaviour of polypropylene (PP) and polypropylene-zeolite composites was investigated. Clinoptilolite, a natural zeolitic tuff, was used as the filling material into the composites. Effect of both pure clinoptilolite and silver ion exchanged form of clinoptilolite addition on the thermal degradation kinetics of polypropylene composites was studied by using differential scanning calorimetry (DSC) and thermal gravimetry analysis (TGA) techniques. Polymer degradation was evaluated by using DSC with heating rates of 5, 10, and 20 degrees C/ min from room temperature up to 500 degrees C. Silver concentration (4.36, 27.85 and 183.8 mg Ag/g zeolite) was the selected parameter under consideration. From the DSC curves, it was observed that the heat of degradation values of the composites containing 2-6% silver exchanged zeolites (321-390 kJ/kg) were larger compared to that of the pure PP free of silver and zeolite (258 kJ/kg). From the DSC results it was confirmed that PP-zeolite composites can be used at higher temperatures compared to the pure PP polymer because of its higher thermal stability. The thermal decomposition activation energies of the composites were calculated by using both the Kissenger and Ozawa models. The values predicted from these two equations were in close agreement. From the TGA curves, it was found that zeolite addition into the PP matrix speeds down the decomposition reaction, however, silver exchanged zeolite addition into the matrix accelerates the reaction. The higher the silver concentration, the lower the thermal decomposition activation energies were obtained. As a result, PP was found to be much more susceptible to thermal decomposition in the presence of silver exchanged zeolite.
  • Article
    Citation - WoS: 54
    Citation - Scopus: 64
    Bioactive Fish Scale Incorporated Chitosan Biocomposite Scaffolds for Bone Tissue Engineering
    (Elsevier Ltd., 2019) Kara, Aylin; Tamburacı, Sedef; Tıhmınlıoğlu, Funda; Havıtçıoğlu, Hasan
    Recently, biologically active natural macromolecules have come into prominence to be used as potential materials in scaffold design due to their unique characteristics which can mimic the human tissue structure with their physical and chemical similarity. Among them, fish scale (FS) is a biologically active material with its structural similarity to bone tissue due to including type I collagen and hydroxyapatite and also have distinctive collagen arrangement. In the present study, it is aimed to design a novel composite scaffold with FS incorporation into chitosan (CH) matrix for bone tissue regeneration. Therefore, two biological macromolecules, fish scale and chitosan, were combined to produce bio-composite scaffold. First, FS were decellularized with the chemical method and disrupted physically as microparticles (100 in), followed by dispersal in CH with ultrasonic homogenisation, CH/FS scaffolds were fabricated by lyophilization technique. Scaffolds were characterized physically, chemically, mechanically, and morphologically. SEM and porosity results showed that CH/FS scaffolds have uniform pore structure showing high porosity. Mechanical properties and degradation rate are enhanced with increasing FS content. In vitro cytotoxicity, proliferation and osteogenic activity of the scaffolds were evaluated with SaOS-2 cell line. CH/FS scaffolds did not show any cytotoxicity effect and the cells were gradually proliferated during culture period. Cell viability results showed that, FS microparticles had a proliferative effect on SaOS-2 cells when compared to control group. ALP activity and biomineralization studies indicated that FS micro particle reinforcement increased osteogenic activity during culture period. As a biological macromolecule with unique characteristics, FS was found as cytocompatible and provided promising effects as reinforcement agents for polymeric scaffolds. In conclusion, fabricated CH/FS bio-composites showed potential for bone tissue engineering applications. (C) 2019 Elsevier B.V. All rights reserved.
  • Article
    Citation - WoS: 69
    Citation - Scopus: 77
    Novel Zein-Based Multilayer Wound Dressing Membranes With Controlled Release of Gentamicin
    (John Wiley and Sons Inc., 2019) Kimna, Ceren; Tamburacı, Sedef; Tıhmınlıoğlu, Funda
    Recently, functional multilayer scaffolds with controlled drug release ability come into prominence for wound healing applications to mimic the layered structure of skin tissue and prevent the possible infections at the defect site. In this study, controlled antibiotic releasing zein bilayer membranes were fabricated for treatment of acute skin infections. Gentamicin loaded fibers were prepared by electrospinning on the membrane surface. Membranes were characterized with scanning electron microscope, atomic force microscopy, Fourier transform infrared spectroscopy, contact angle, mechanical analysis, swelling, degradation, and water vapor permeability studies. In vitro cytotoxicity, cell attachment, and proliferation were investigated. Cell attachment on fiber layer was observed with fluorescence imaging. Fabricated fibers showed structural similarity to the skin tissue layers with a fiber diameter range of 350-425 nm and film thickness in the range of 311-361 mu m. Mechanical properties were found compatible with the skin tissue. In addition, membranes showed antimicrobial activity against Staphylococcus aureus and Escherichia coli. The sustained release was achieved with a cumulative release of 94%. Membranes did not show any cytotoxic effect. NIH/3T3 and HS2 cell lines were proliferated on each layer mimicking the multilayer skin tissue. Hence, zein-based bilayer membrane showed promising properties to be used as a potential antimicrobial wound dressing for skin tissue regeneration. (c) 2018 Wiley Periodicals, Inc.