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The presence of a variety of bacteria is an inevitable/indispensable part of human life. In particular, for patients, the existence and spreading of bacteria lead to prolonged treatment period with many more complications. The widespread use of urinary catheters is one of the main causes for the prevalence of infections. The necessity of long-term use of indwelling catheters is unavoidable in terms of the development of bacteriuria and blockage. As is known, since a permanent solution to this problem has not yet been found, research and development activities continue actively. Herein, polyethylene glycol (PEG)-like thin films were synthesized by a custom designed plasma enhanced chemical vapor deposition (PE-CVD) method and the long-term effect of antifouling properties of PEG-like coated catheters was investigated against Escherichia coli and Proteus mirabilis. The contact angle measurements have revealed the increase of wettability with the increase of plasma exposure time. The antifouling activity of surface-coated catheters was analyzed against the Gram-negative/positive bacteria over a long-term period (up to 30 days). The results revealed that PE-CVD coated PEG-like thin films are highly capable of eliminating bacterial attachment on surfaces with relatively reduced protein attachment without having any toxic effect. Previous statements were supported with SEM, XPS, FTIR spectroscopy, and contact angle analysis. One-step synthesis of PEG-like thin films on urinary catheters with long-term bacterial repellency and biocompatibility., Trkiye Bilimsel ve Teknolojik Arascedil;timath;rma Kurumu [221S775]; Scientific and Technological Research Council of Turkey (TUBITAK); TUBITAK, This study was supported by Scientific and Technological Research Council of Turkey (TUBITAK) under the Grant Number 221S775. The authors thank to TUBITAK for their supports.

Geçici ya da kalıcı, dahili ya da harici olarak, tedavi ve/veya onarım gibi amaçlarla vücuda dahil edilen malzemeler implant materyalleri olarak adlandırılmaktadırlar. Günümüzde artan popülasyon ve uzun yaşam süreleri göz önüne alındığında, implant materyallerin kullanım sıklığı, miktarı ve süreleri giderek artmaktadır. Bu nedenle kullanılan implantların, kullanıldıkları bölgeye uyum sağlamaları, transplantasyon sonrası herhangi bir komplikasyon oluşmasını önleyecek şekilde tasarlanmaları gerektiği sonucuna ulaşılmaktadır. Tez kapsamında polimerik ve metalik alttaşlar olmak üzere iki farklı malzemede heparin adı verilen, klinikte güncel olarak antikoagülan ilaç olarak kullanılan biyomolekül ile yüzey modifikasyon stratejilerinin geliştirilmesi üzerine çalışılmıştır. Polipropilen (PP) tez kapsamında model polimerik malzeme olarak seçilmiş ve iki basamakta plazma polimerizasyon (PlzP) destekli yüzey modifikasyonu gerçekleştirilmiştir; (i) oksijen ile aşındırma ve (ii) amince zengin fonksiyonel grup oluşturma. PlzP tekniği ile geliştirilen yüzey modifikasyon parametreleri, temas açısı ölçüm, serbest yüzey enerji hesaplamaları, yüzeyde maksimum azot miktarını elde etme, yüzey pürüzlük değerinin artırılması kriterleri kapsamında değerlendirilmiş ve optimize parametre tespit edilmiştir. Heparin immobilizasyon işlemi, saf heparin (hep) ve kovalent bağ ajanları ile destekli (hep*) çözeltiler kullanılarak 3 farklı konsantrasyon üzerinden test edilmiştir. Yüzeye tutunumu sağlanan heparin miktarı Toluidine Mavi (TB) boya ile tespit edilmiş ve maksimum heparin tutunumunun sağlandığı konsantrasyon, optimize parametre olarak belirlenmiştir. Kovalent bağ ajanları ile destekli heparin çözeltisinin iki basamakta modifiye edilen PP yüzeyler ile kovalent bağ oluşturduğu, FTIR-ATR analizinde saptanan amid I ve II pikleri ile kanıtlanmıştır. Heparin immobilizasyonu protein tutunum miktarını referans yüzeylere göre oldukça azaltmış, hemokompatibilite testleri kapsamında (platelet tutunum, Implantable materials are tools that are used in the human body for temporary or permanent, internal or external, treatment or repair, and so on. Nowadays, due to the growing population and long lifetime, the rate, quantity, and duration of these materials are also increasing. Therefore, implantable materials should be biocompatible with the environment in their usage area and be designed to prevent any complications after the transplant. Within the scope of this thesis, two different materials were used as polymeric and metallic substrates for surface modification with an anticoagulation drug that is used in clinics, heparin. Polypropylene (PP) was selected as a model polymeric substrate and plasma-assisted surface modification was applied in two steps: (i) oxygen etching and (ii) amine-rich functional group creation. Surface modification parameters that were held with the plasma polymerization (PlzP) technique were analyzed with contact angle measurements, surface free energy calculations, obtaining the maximum nitrogen amount on the surfaces and increasing the surface roughness values, etc., and the parameters were optimized accordingly. Immobilization of heparin applied as pure heparin (hep) and covalent bond agent assisted (hep*) with 3 different concentration values. The amount of immobilized heparin detected with toluidine blue (TB) dye and the parameter that produces the maximum amount of immobilized heparin were selected as optimal. Covalent bond formation between hep* and PP substrates was proven with amide I and II peaks, which were detected with FTIR-ATR analysis. Compared to the bare PP substrates, heparin immobilization provided a lower amount of adhered protein and much more efficient hemocompatibility testing (platelet adhesion, hemolysis, and kinetic blood coagulation rate) results. Also, the antiadhesive characteristics of heparin-immobilized PP surfaces were tested against both gram-positive and gram-negative bacteria strains, and the antibacteria

The inferior hemocompatibility or antibacterial properties of blood-contacting materials and devices are restraining factors that hinder their successful clinical utilization. To highlight these, a plasma-enhanced modification strategy is favored for surface tailoring of an extensively used biomaterial, polypropylene (PP). The surface activation of the PPs is achieved by oxygen plasma etching and subsequent surface functionalization through amine-rich precursor mediated coating by plasma glow discharge. After optimum plasma processing parameters are decided, heparin (anticoagulant and antithrombic drug) is either attached or covalently conjugated on the PPs' surfaces. The aminated films produced at 75 W plasma power with 15 min exposure time are highly hydrophilic (34.72 +/- 5.92 degrees) and surface active (65.91 mJ m(-2)), facilitating high capacity heparin immobilization (approximate to 440 mu g cm(-2)) by covalent linkage. The kinetic-blood coagulation rate and protein adhesion amount on the plasma-mediated heparinized PPs are decreased about tenfold and 15-fold, and platelet adhesion is markedly lowered. In addition, heparinized-PP surfaces comprise superior antibacterial activity against gram-positive/-negative bacteria conveyed particularly by contact-killing (99%). The heparin-coating did not cause cytotoxicity on fibroblast cells, instead enhanced their proliferation, as shown by the (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay. Overall, this simple methodology is highly proficient in becoming a universal strategy for developing dual-functionalized blood-contacting materials.

The objectives of this study were to assess Candida spp. distribution and antifungal resistance of candidaemia across Europe. Isolates were collected as part of the third ECMM Candida European multicentre observational study, conducted from 01 to 07-07-2018 to 31-03-2022. Each centre (maximum number/country determined by population size) included ∼10 consecutive cases. Isolates were referred to central laboratories and identified by morphology and MALDI-TOF, supplemented by ITS-sequencing when needed. EUCAST MICs were determined for five antifungals. fks sequencing was performed for echinocandin resistant isolates. The 399 isolates from 41 centres in 17 countries included C. albicans (47.1%), C. glabrata (22.3%), C. parapsilosis (15.0%), C. tropicalis (6.3%), C. dubliniensis and C. krusei (2.3% each) and other species (4.8%). Austria had the highest C. albicans proportion (77%), Czech Republic, France and UK the highest C. glabrata proportions (25–33%) while Italy and Turkey had the highest C. parapsilosis proportions (24–26%). All isolates were amphotericin B susceptible. Fluconazole resistance was found in 4% C. tropicalis, 12% C. glabrata (from six countries across Europe), 17% C. parapsilosis (from Greece, Italy, and Turkey) and 20% other Candida spp. Four isolates were anidulafungin and micafungin resistant/non-wild-type and five resistant to micafungin only. Three/3 and 2/5 of these were sequenced and harboured fks-alterations including a novel L657W in C. parapsilosis. The epidemiology varied among centres and countries. Acquired echinocandin resistance was rare but included differential susceptibility to anidulafungin and micafungin, and resistant C. parapsilosis. Fluconazole and voriconazole cross-resistance was common in C. glabrata and C. parapsilosis but with different geographical prevalence., The objectives of this study were to assess Candida spp. distribution and antifungal resistance of candidaemia across Europe. Isolates were collected as part of the third ECMM Candida European multicentre observational study, conducted from 01 to 07-07-2018 to 31-03-2022. Each centre (maximum number/country determined by population size) included ∼10 consecutive cases. Isolates were referred to central laboratories and identified by morphology and MALDI-TOF, supplemented by ITS-sequencing when needed. EUCAST MICs were determined for five antifungals. fks sequencing was performed for echinocandin resistant isolates. The 399 isolates from 41 centres in 17 countries included C. albicans (47.1%), C. glabrata (22.3%), C. parapsilosis (15.0%), C. tropicalis (6.3%), C. dubliniensis and C. krusei (2.3% each) and other species (4.8%). Austria had the highest C. albicans proportion (77%), Czech Republic, France and UK the highest C. glabrata proportions (25–33%) while Italy and Turkey had the highest C. parapsilosis proportions (24–26%). All isolates were amphotericin B susceptible. Fluconazole resistance was found in 4% C. tropicalis, 12% C. glabrata (from six countries across Europe), 17% C. parapsilosis (from Greece, Italy, and Turkey) and 20% other Candida spp. Four isolates were anidulafungin and micafungin resistant/non-wild-type and five resistant to micafungin only. Three/3 and 2/5 of these were sequenced and harboured fks-alterations including a novel L657W in C. parapsilosis. The epidemiology varied among centres and countries. Acquired echinocandin resistance was rare but included differential susceptibility to anidulafungin and micafungin, and resistant C. parapsilosis. Fluconazole and voriconazole cross-resistance was common in C. glabrata and C. parapsilosis but with different geographical prevalence.