PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7645
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Conference Object Citation - WoS: 24Effect of pH and Hydration on the Normal and Lateral Interaction Forces Between Alumina Surfaces(2006) Polat, Mehmet; Sato, Kimiyasu; Nagaoka, Takaaki; Watari, KojiNormal and lateral interaction forces between alumina surfaces were measured using Atomic Force Microscopy-Colloid Probe Method at different pH. The normal force curves exhibit a well-defined repulsive barrier and an attractive minimum at acidic pH and the DLVO theory shows excellent agreement with the data. The normal forces are always repulsive at basic pH and the theory fails to represent the measurements. Lateral forces are almost an order of magnitude smaller in the basic solutions. These differences, which have important implications in the study of stability and rheology, are attributed to the hydration of the alumina surface at basic pH. © 2013 Elsevier B.V., All rights reserved.Article Citation - WoS: 139Granulocytic Sarcoma: a Systematic Review(e-Century Publishing Corporation, 2013) Yılmaz, Asu Fergün; Saydam, Güray; Şahin, Fahri; Baran, YusufGranulocytic sarcoma also called myeloid sarcoma is an extramedullary tumor of immature granulocytic cells. It is a rare entity, and mostly accompanied by acute myeloid leukemia. It is observed during the course of myeloproliferative disorders especially in chronic myeloid leukemia and myelodysplastic syndromes. In some rare circumstances, it is detected before clinical signs of leukemia or other diseases. When the bone marrow biopsy reveals no other hematologic malignancies, the granulocytic sarcoma is described as nonleukemic, primary or isolated. It is observed at any part of the body but the most common locations are soft tissues, bone, peritoneum and lymph nodes. Presenting signs or symptoms are mainly due to mass effect of the tumor and dysfunction of the organ, or the tissue that is affected. The diagnosis is performed by biopsy of the tumor. The tumor consists of immature granulocytic cells, which could be documented by H&E, immunohistochemistry, and flow cytometric methods. Fluorescence in-situ hybridization and molecular analysis are also performed. The optimal time and type of treatment is not clear. Surgery could be an option especially for tumors, which cause organ dysfunction and/or obstruction. Systemic treatment should be considered in all patients because without systemic treatment, relapses and progression to acute myeloid leukemia is the ultimate fate of the disease in many cases. Cytarabine-containing remission-induction chemotherapies have been the most applied therapeutic strategies, but it is not clear whether the consolidation therapies are required or not, and what kind of regimens are appropriate. The role of hematopoietic stem cell transplantation (HSC) as a consolidation regimen is not clear, but, after the relapse of the disease with or without bone marrow involvement, HSC transplantation should be considered in suitable patients after the reinduction performed by AML chemotherapies. There is only limited data about the role of radiotherapy in these patients. It could be used in patients with relapsed disease, organ dysfunction which should be quickly relieved and inadequate response to chemotherapy. The effect of radiotherapy on overall survival is not known. New prospective studies and clinical trials are needed to generate guidelines for the treatment of primary granulocytic sarcomas.Article Citation - WoS: 3Citation - Scopus: 3Automated Labeling of Cancer Textures in Larynx Histopathology Slides Using Quasi-Supervised Learning(Science Printers and Publishers Inc., 2014) Önder, Devrim; Sarıoğlu, Sülen; Karaçalı, BilgeOBJECTIVE: To evaluate the performance of a quasisupervised statistical learning algorithm, operating on datasets having normal and neoplastic tissues, to identify larynx squamous cell carcinomas. Furthermore, cancer texture separability measures against normal tissues are to be developed and compared either for colorectal or larynx tissues. STUDY DESIGN: Light microscopic digital images from histopathological sections were obtained from laryngectomy materials including squamous cell carcinoma and nonneoplastic regions. The texture features were calculated by using co-occurrence matrices and local histograms. The texture features were input to the quasisupervised learning algorithm. RESULTS: Larynx regions containing squamous cell carcinomas were accurately identified, having false and true positive rates up to 21% and 87%, respectively. CONCLUSION: Larynx squamous cell carcinoma versus normal tissue texture separability measures were higher than colorectal adenocarcinoma versus normal textures for the colorectal database. Furthermore, the resultant labeling performances for all larynx datasets are higher than or equal to that of colorectal datasets. The results in larynx datasets, in comparison with the former colorectal study, suggested that quasi-supervised texture classification is to be a helpful method in histopathological image classification and analysis.Article Citation - WoS: 43Citation - Scopus: 47Bioactive Diatomite and Poss Silica Cage Reinforced Chitosan/Na-carboxymethyl Cellulose Polyelectrolyte Scaffolds for Hard Tissue Regeneration(Elsevier, 2019) Tamburacı, Sedef; Kimna, Ceren; Tıhmınlıoğlu, FundaRecently, natural polymers are reinforced with silica particles for hard tissue engineering applications to induce bone regeneration. In this study, as two novel bioactive agents, effects of diatomite and polyhedral oligomeric silsesquioxanes (POSS) on chitosan (CS)/Na-carboxymethylcellulose (Na-CMC) polymer blend scaffolds are examined. In addition, the effect of silica reinforcements was compared with Si-substituted nano-hydroxyapatite (Si-Hap) particles. The morphology, physical and chemical structures of the scaffolds were characterized with SEM, liquid displacement, FT-IR, mechanical analysis, swelling and degradation studies. The particle size and the crystal structure of diatomite, POSS and Si-Hap particles were determined with DLS and XRD analyses. In vitro studies were performed to figure out the cytotoxicity, proliferation, ALP activity, osteocalcin production and biomineralization to demonstrate the promising use of natural silica particles in bone regeneration. Freeze-dried scaffolds showed 190-307 mu m pore size range and 61-70% porosity. Both inorganic reinforcements increased the mechanical strength, enhanced the water uptake capacity and fastened the degradation rate. The nanocomposite scaffolds did not show any cytotoxic effect and enhanced the surface mineralization in osteogenic medium. Thus, diatomite and POSS cage structures can be potential reinforcements for nanocomposite design in hard tissue engineering applications.Article Citation - WoS: 14Citation - Scopus: 18Comparison of Antimicrobial Activity of Allium Sativum Cloves From China and Taskopru, Turkey(Hindawi Publishing Corporation, 2018) Yetgin, Ali; Canlı, Kerem; Altuner, Ergin MuratIn this study, antimicrobial activities of two different samples of Allium sativum L. from Turkey (TR) (Taskopru, Kastamonu, Turkey) and China (CN) were determined. A broad spectrum of Gram-negative and Gram-positive bacteria (17 bacteria) including species of Bacillus, Enterobacter, Enterococcus, Escherichia, Klebsiella, Listeria, Pseudomonas, Salmonella, and Staphylococcus were used for testing antibacterial activity. In addition, antifungal activity against Candida albicans was also investigated. Antimicrobial activity was tested by using 3 different processes (chopping, freezing, and slicing by the disk diffusion method). The results showed that TR garlic presented more antimicrobial activity than CN garlic. Mechanism of activity of CN garlic could be proposed to be different from that of TR garlic.Article Citation - WoS: 12Effects of Fat Reduction on the Stability, Microstructure, Rheological and Color Characteristics of White-Brined Cheese Emulsion With Different Emulsifying Salt Amounts(Korean Society for Food Science of Animal Resources, 2018) Urgu, Müge; Ünlütürk, Sevcan; Koca, NurcanCheese emulsion is an intermediate product for the production of cheese powder and needs to be stable, homogeneous and pumpable characteristics to convey to the spray drier. This study was conducted to evaluate the effects of fat reduction and emulsifying salt (ES) amount in cheese emulsion systems on the physicochemical characteristics. Reduced-fat (RF) and full-fat (FF) white-brined cheese emulsions were produced with different dry matters (DM; 15%-25% excluding ES) and ES concentrations (0%-3% based on cheese weight). Stable cheese emulsion was obtained at lower DM in RF cheese emulsion than that of FF cheese emulsion. Reduction in the amount of ES resulted in instability of both emulsions. Apparent viscosity with pseudoplastic flow behavior significantly increased with the decrease of fat content in stable cheese emulsions. Microstructure of emulsions appeared to be related to the fat content, stability and degree of emulsification. Reduction of fat content caused to get less lightness and more greenness in color, whereas yellowness was significantly decreased by increase in the amount of ES. In conclusion, fat reduction resulted in higher viscosities of cheese emulsion due to inducing the increment of protein, and the addition amount of ES considered as very important factor to produce stable cheese emulsion without protein precipitation or cream separation. Therefore, for preparation of RF cheese emulsion using a variety of white-brined cheese, lower amounts of DM would be suggested in this study to obtain homogenous droplets in the atomizing process of spray drying.Article Citation - WoS: 22Citation - Scopus: 26In Vitro Antimicrobial Activity Screening of Ethanol Extract of Lavandula Stoechas and Investigation of Its Biochemical Composition(Hindawi Publishing Corporation, 2019) Canlı, Kerem; Yetgin, Ali; Benek, Atakan; Bozyel, Mustafa Eray; Altuner, Ergin MuratThe aim of this study was to test antimicrobial activity of ethanol extract of Lavandula stoechas against 22 bacteria and 1 yeast. Also, biochemical composition of the extract was investigated. A wide range of Gram-positive, Gram-negative microorganisms, and multidrug resistant bacteria were selected to test the antimicrobial activity. As a result, the extract is observed to contain fenchone (bicyclo[2.2.1]heptan-2-one, 1,3,3-trimethyl-, (1R)-) and camphor (+)-2-bornanone) as major components and showed antimicrobial activity against all studied microorganisms except Escherichia coli ATCC 25922 and Klebsiella pneumoniae. The results of the study present that L. stoechas is active against MDR strains too.Article Citation - WoS: 62Citation - Scopus: 72Diatomite Reinforced Chitosan Composite Membrane as Potential Scaffold for Guided Bone Regeneration(Elsevier Ltd., 2017) Tamburacı, Sedef; Tıhmınlıoğlu, FundaIn this study, natural silica source, diatomite, incorporated novel chitosan based composite membranes were fabricated and characterized for bone tissue engineering applications as possible bone regeneration membrane. The effect of diatomite loading on the mechanical, morphological, chemical, thermal and surface properties, wettability and in vitro cytotoxicity and cell proliferation on of composite membranes were investigated and observed by tensile test, atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), protein adsorption assay, air/water contact angle analysis and WST-1 respectively. Swelling studies were also performed by water absorption capacity determination. Results showed that incorporation of diatomite to the chitosan matrix increased the surface roughness, swelling capacity and tensile modulus of membranes. An increase of about 52% in Young's modulus was achieved for 10 wt% diatomite composite membranes compared with chitosan membranes. High cell viability results were obtained with indirect extraction method. Besides, in vitro cell proliferation and ALP activity results showed that diatom incorporation significantly increased the ALP activity of Saos-2 cells cultured on chitosan membranes. The novel composite membranes prepared in the present study with tunable properties can be considered as a potential candidate as a scaffold in view of its enhanced physical & chemical properties as well as biological activities for bone tissue engineering applications.Article Citation - WoS: 2Citation - Scopus: 2Scanning Probe Oxidation Lithography on Ta Thin Films(American Scientific Publishers, 2008) Okur, Salih; Büyükköse, Serkan; Tarı, SüleymanA Semi-Contact Scanning Probe Lithography Technique (SC-SPL) has been applied to create nano-oxide patterns on Ta thin films grown by DC magnetron sputtering method on SiO 2/Si substrates. The height and linewidth profiles of nano-oxide lines created by a conductive AFM tip on Ta film surfaces were measured as a function of applied voltage, oxidation time, humidity, and tip apex curvature. The AFM surface measurements show that the height of the oxides increases linearly with increasing voltage; but there was no oxide growth, when less than 4 V was applied even at 85% relative humidity. Electrical measurements were performed and the resistivities of the TaO x layer and Ta film were obtained as 5.76 × 10 8 and 1.4 × 10 5 Ohm-cm, respectively.Article Citation - WoS: 76Citation - Scopus: 79Near-Surface Viscosity Effects on Capillary Rise of Water in Nanotubes(American Physical Society, 2015) Vo, Truong Quoc; Barışık, Murat; Kim, BoHungIn this paper, we present an approach for predicting nanoscale capillary imbibitions using the Lucas-Washburn (LW) theory. Molecular dynamics (MD) simulations were employed to investigate the effects of surface forces on the viscosity of liquid water. This provides an update to the modified LW equation that considered only a nanoscale slip length. An initial water nanodroplet study was performed to properly elucidate the wetting behavior of copper and gold surfaces. Intermolecular interaction strengths between water and corresponding solid surfaces were determined by matching the contact angle values obtained by experimental measurements. The migration of liquid water into copper and gold capillaries was measured by MD simulations and was found to differ from the modified LW equation. We found that the liquid layering in the vicinity of the solid surface induces a higher density and viscosity, leading to a slower MD uptake of fluid into the capillaries than was theoretically predicted. The near-surface viscosity for the nanoscale-confined water was defined and calculated for the thin film of water that was sheared between the two solid surfaces, as the ratio of water shear stress to the applied shear rate. Considering the effects of both the interface viscosity and slip length of the fluid, we successfully predicted the MD-measured fluid rise in the nanotubes.