WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394
Browse
40 results
Search Results
Article Borax-Doped Fe2O3 and CeO2 Nanoparticles Regulate Dose-Dependently Inflammation, the Cell Cycle, and Migration in LPS-Activated THP-1 Cells(Wiley-VCH Verlag GmbH, 2026-03) Sulak, Mine; Ceylan Ekiz, Yağmur; Şen, Alaattin; Acar, Büşra; Çelik Turgut, Gurbet; Aktaş Pepe, NihanThis study examined the biological effects of borax-doped Fe2O3 and CeO2 nanoparticles (NPs) on lipopolysaccharide (LPS)-activated THP-1 cells. The morphology and composition of the nanocomposites were confirmed via scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX). Cell viability (resazurin and crystal violet assays), apoptosis/necrosis (annexin V/propidium iodide [PI]), cell cycle (flow cytometry), migration (scratch assay), and inflammatory response (Iba1 immunofluorescence staining, inducible nitric oxide synthase [iNOS] activity, and RT-PCR) were evaluated. The particle sizes ranged from 21.34 to 33.47 nm (Fe2O3-B-NPs) and 31.07 to 36.62 nm (CeO2-B-NPs). The IC10 and IC50 dose ranges were defined for each nanocomposite and applied across different cell lines to evaluate dose-dependent biological effects. Fe2O3-B-NPs altered cell cycle progression, increasing the number of S phase cells. Both nanocomposites promoted migration at low doses but inhibited it at high doses. CeO2-B-NPs reduced Iba1 levels, whereas Fe2O3-B-NPs increased inflammatory marker levels at higher concentrations. CeO2-B-NPs suppressed TNF-alpha and IL-1 beta gene expression at the IC50 dose, while both nanocomposites reduced iNOS activity. These results indicate that the dose-dependent effects of nanocomposites should be carefully evaluated.Article Citation - WoS: 1Citation - Scopus: 1Ultra-Durable Information-Encoded Anti-Counterfeiting Self-Assembled Nanocrystal Labels(Wiley-VCH Verlag GmbH, 2025-11-28) Haddadifam, Taha; Shabani, Farzan; Kalay, Mustafa; Khaligh, Aisan; Mutlugun, Evren; Onses, Mustafa Serdar; Demir, Hilmi VolkanForgery, a serious universal problem, is causing huge economic losses every year. Against forgery, information-encoded labelling systems have attracted significant attention for a diverse range of anti-counterfeiting applications. Here, cost-effective and ultra-durable nanocrystal-based labels are proposed and demonstrated in which information can be encoded as physically unclonable functions (PUFs) of hardware-oriented security systems. The fabrication method of the PUFs is based on the self-assembly of colloidal quantum wells (CQWs) and generation of unclonable features within their pattern at a liquid-liquid interface. These CQW PUFs are analyzed with well-known statistical tests, which show a uniqueness level of 0.5060 +/- 0.0323 and prove their randomness. In addition, a feature-matching algorithm is used to authenticate these information-encoded CQW PUFs. For the safety of the semiconductor chips, a CQW PUF is attached to the surface of the chip to protect against hardware cyber-attacks. Eventually, fabricated labels are examined against high temperatures and moisture environments. The fabricated CQW label is durable for a period of 150 days it is tested, demonstrating ultra-high stability of the label. High stability and durability, cost-effectiveness, and high encoding capacity make these proposed nanocrystal labels extremely attractive for large-scale commercialization.Article Toward the Design of New Α-Carboline Derivatives Against Anaplastic Lymphoma Kinase (Alk): A Comprehensive in Silico Approach(Wiley-VCH Verlag GmbH, 2025-11) Sari, Ceyhun; Akcok, IsmailAfter the first description of anaplastic lymphoma kinase (ALK) in an anaplastic large cell lymphoma cell line as a nucleophosmin (NPM) fusion partner, ALK and its various fusion partners have been implicated in numerous cancers such as non-small cell lung cancer (NSCLC), anaplastic large cell lymphoma (ALCL), neuroblastoma, and rhabdomyosarcoma. In the last decade, several compounds targeting ALK have been developed and approved by the Food and Drug Administration (FDA). Despite the advances of generations of ALK inhibitors, a recent study highlighted that around half of the ALK-positive NSCLC patients will go through disease progression in response to first-line alectinib, which is a second-generation ALK inhibitor. In this study, we aimed to propose a novel alpha-carboline compound targeting the ALK tyrosine kinase domain to be used against various types of cancer in which ALK fusion proteins may be involved. In this regard, we designed more than 200 alpha-carboline derivatives and investigated their binding properties against ALK tyrosine kinase by using in silico protocols consisting of molecular docking studies, molecular dynamics simulations, MM/PBSA binding free energy calculation, and essential dynamics analysis. Considering the obtained results, we developed two promising candidates, compounds 208 & 209 with -9.05 and -9.80 binding energies, respectively, which demonstrated improved binding profiles over the course of a 300 ns simulation.Article Citation - WoS: 8Citation - Scopus: 8Thermo-Responsive Complexes of c-Myc Antisense Oligonucleotide With Block Copolymer of Poly(OEGMA) and Quaternized Poly(4-Vinylpyridine)(Wiley-VCH Verlag GmbH, 2016-11-03) Topuzogullari, Murat; Elalmis, Yeliz Basaran; Isoglu, Sevil DincerSolution behavior of thermo-responsive polymers and their complexes with biological macromolecules may be affected by environmental conditions, such as the concentration of macromolecular components, pH, ion concentration, etc. Therefore, a thermo-responsive polymer and its complexes should be characterized in detail to observe their responses against possible environments under physiological conditions before biological applications. To briefly indicate this important issue, thermo-responsive block copolymer of quaternized poly(4-vinylpyridine) and poly(oligoethyleneglycol methyl ether methacrylate) as a potential nonviral vector has been synthesized. Polyelectrolyte complexes of this copolymer with the antisense oligonucleotide of c-Myc oncogene are also thermo-responsive but, have lower LCST (lower critical solution temperature) values compared to individual copolymer. LCST values of complexes decrease with molar ratio of macromolecular components and presence of salt. Dilution of solutions also affects solution behavior of complexes and causes a significant decrease in size and an increase in LCST, which indicates possible effects of severe dilutions in the blood stream.Article Citation - WoS: 6Citation - Scopus: 7Therapeutic Potential of Nitrogen-Substituted Oleanolic Acid Derivatives in Neuroinflammatory and Cytokine Pathways: Insights From Cell-Based and Computational Models(Wiley-VCH Verlag GmbH, 2025-04-22) Turgut, Gurbet Celik; Pepe, Nihan Aktas; Ekiz, Yagmur Ceylan; Senol, Halil; Sen, AlaattinThis study was conducted to investigate the mechanism of the potential and anti-inflammatory properties of nitrogen-substituted oleanolic acid derivatives that can be used to treat neuroinflammatory diseases. Nitrogen-containing oleanolic acid derivatives have been evaluated for their anti-neuroinflammatory effects in vitro in neuronal and monocytic cell lines at nontoxic doses, and the production of cytokines (TNF-alpha, IL-6 and IL-17), the inflammatory enzyme induced nitric oxide synthase (iNOS) and NF-kappa B signalling under LPS-stimulated conditions, and the expression of genes associated with Alzheimer's disease have been assessed. In addition, molecular docking and molecular dynamics simulation assessments are conducted in silico. Key protein markers of neurodegenerative diseases, especially Alzheimer's disease and neuroinflammation, TAU protein levels, and microglial activation, as well as ionised calcium-binding adaptor protein-1 (IBA1) levels, were significantly reduced with the addition of oleanolic acid derivatives. LPS-induced NF-kappa B luciferase reporter activity and iNOS activity were significantly inhibited, approaching the levels in uninduced controls. The mRNA expression of proinflammatory cytokines critical for neuroinflammation, such as TNF-alpha, NF-kappa B, IL-6 and IL-17, was reduced twofold to sevenfold. Furthermore, the molecular docking and MD simulation analyses revealed potential interactions with the TNF-alpha and NF-kappa B proteins. These findings underscore the potential of oleanolic acid derivatives, particularly compound 16, as candidates for further development as therapeutic agents for neurodegenerative diseases associated with chronic inflammation.Article Citation - WoS: 23Citation - Scopus: 21Tattoo-Like Multi-Color Physically Unclonable Functions(Wiley-VCH Verlag GmbH, 2023-12-07) Kiremitler, N. Burak; Esidir, Abidin; Drake, Gryphon A.; Yazici, Ahmet Faruk; Sahin, Furkan; Torun, Ilker; Onses, M. SerdarAdvanced anti-counterfeiting and authentication approaches are in urgent need of the rapidly digitizing society. Physically unclonable functions (PUFs) attract significant attention as a new-generation security primitive. The challenge is design and generation of multi-color PUFs that can be universally applicable to objects of varied composition, geometry, and rigidity. Herein, tattoo-like multi-color fluorescent PUFs are proposed and demonstrated. Multi-channel optical responses are created by electrospraying of polymers that contain semiconductor nanocrystals with precisely defined photoluminescence. The universality of this approach enables the use of dot and dot-in-rod geometries with unique optical characteristics. The fabricated multi-color PUFs are then transferred to a target object by using a temporary tattoo approach. Digitized keys generated from the red, green and blue fluorescence channels facilitate large encoding capacity and rapid authentication. Feature matching algorithms complement the authentication by direct image comparison, effectively alleviating constraints associated with imaging conditions. The strategy that paves the way for the development of practical, cost-effective, and secure anticounterfeiting systems is presented. Tattoo-like multi-color encoding layers based on random processing of semiconductor nanocrystals of varied composition and geometry are reported. Additive deposition via chaotic electrospraying enables randomness and multiplexing, whereas the tattoo approach provides substrate independence.imageArticle Citation - WoS: 3Citation - Scopus: 3Superior CdSe/ZnS@Fe2O3 Yolk-Shell Nanoparticles as Optically Active MRI Contrast Agents(Wiley-VCH Verlag GmbH, 2022-07) Ekici, Derya D.; Mutlugun, EvrenWe have developed a robust synthesis methodology for quantum dots (QDs) nanoparticles with magnetic properties designed for biomodal imaging. These nanocrsytlas consists of a semiconductor quantum dot core with engineered fluorescence, which is located in a paramagnetic iron oxide shell that acts as a magnetic resonance imaging (MRI) contrast agent. Yolk-shell CdSe/ZnS@Fe2O3 nanoparticles (NPs) are synthesized via sonochemical decomposition of iron pentacarbonyl (Fe(CO)(5)) using the oleylamine (OAm) as the ligand. The sonochemical synthesis method of magnetic fluorescent NPs that can be used as MRI contrast agents provided advantages such as improved quantum efficiency and homogeneous size distributions. It has been determined that the luminescence efficiency of quantum dots decreases in coatings that can be made at high temperatures by thermal decomposition. In order to eliminate the disadvantage of elevated temperatures, the sonochemical decomposition method, which allows coating at low temperatures, has been used. With this method, yolk-shell (CdSe/ZnS@Fe2O3) nanoparticles were produced with high photoluminescence quantum efficiency and homogeneous size distributions. The synthesis magnetic fluorescent NPs optimized was determined to have the injection temperature of Fe(CO)(5) at 60 degrees C, Fe(CO)(5)/CdSe@ZnS ratio 0.7, OAm/Fe(CO)(5) volume ratio 1.43 with an oxidation time 5 min. Under these conditions, the quantum efficiency was found to be 78 %, nanoparticle sizes between 11-14 nm and r(1) value was 0.199, r(2) value was 0.518 in MRI analysis. These optically active magnetic fluorescent nanoparticles as positive contrast agents (T1 weighted) are predicted to pave the way for the future of advanced bio-imaging systems.Article Citation - WoS: 1Citation - Scopus: 1Stochastic Orientational Encoding via Hydrogen Bonding Driven Assembly of Woven-Like Molecular Physically Unclonable Functions(Wiley-VCH Verlag GmbH, 2025-07-02) Kayaci, Nilgun; Kiremitler, Nuri Burak; Deneme, Ibrahim; Kalay, Mustafa; Ozbasaran, Aleyna; Zorlu, Yunus; Usta, HakanThe prevention of counterfeiting and the assurance of object authenticity require stochastic encoding schemes based on physically unclonable functions (PUFs). There is an urgent need for exceptionally large encoding capacities and multi-level responses within a molecularly defined, single-material system. Herein, a novel stochastic orientational encoding approach is demonstrated using a facile ambient-atmosphere solution processing of a molecular thin film based on the rod-shaped oligo(p-phenyleneethynylene) (OPE) pi-architecture. The nanoscopic film, derived from the small molecule 2EHO-CF3PyPE with donor, acceptor, and pi-spacer building units, is designed for energetically favorable uniaxial molecular assembly and crystal growth via directional multiple hydrogen-bonding motifs at the molecular termini and short C & horbar;H<middle dot><middle dot><middle dot>pi contacts at the center. A facile solvent vapor annealing induces concurrent dewetting and microscopic 1D random crystallization, yielding a woven-textured random features. Using convolutional neural networks, the rich variations in microcrystal domain properties and stochastic encoding of 1D crystal orientations generate artificial coloration, achieving an encoding capacity reaching (6.5 x 10(4))(2752 x 2208). The results demonstrate an effective strategy for achieving ultrahigh encoding capacities in a thin film composed of a single-material. This approach enables low-cost, solution-processed fabrication for mass production and broad adoption, while opening new opportunities to explore molecular-PUFs through structural design and engineering noncovalent interactions.Article Citation - WoS: 11Citation - Scopus: 9Single-Mode Lasing From a Single 7 nm Thick Monolayer of Colloidal Quantum Wells in a Monolithic Microcavity(Wiley-VCH Verlag GmbH, 2021-03-03) Foroutan-Barenji, Sina; Erdem, Onur; Delikanli, Savas; Yagci, Huseyin Bilge; Gheshlaghi, Negar; Altintas, Yemliha; Demir, Hilmi VolkanIn this work, the first account of monolithically-fabricated vertical cavity surface emitting lasers (VCSELs) of densely-packed, orientation-controlled, atomically flat colloidal quantum wells (CQWs) using a self-assembly method and demonstrate single-mode lasing from a record thin colloidal gain medium with a film thickness of 7 nm under femtosecond optical excitation is reported. Specially engineered CQWs are used to demonstrate these hybrid CQW-VCSELs consisting of only a few layers to a single monolayer of CQWs and are achieved the lasing from these thin gain media by thoroughly modeling and implementing a vertical cavity consisting of distributed Bragg reflectors with an additional dielectric layer for mode tuning. Accurate spectral and spatial alignment of the cavity mode with the CQW films is secured with the help of full electromagnetic computations. While overcoming the long-pending problem of limited electrical conductivity in thicker colloidal films, such ultrathin colloidal gain media can be helpful to enable fully electrically-driven colloidal lasers.Article Citation - WoS: 36Citation - Scopus: 36Selective Remanent Ambipolar Charge Transport in Polymeric Field-Effect Transistors for High-Performance Logic Circuits Fabricated in Ambient(Wiley-VCH Verlag GmbH, 2014-10-06) Fabiano, Simone; Usta, Hakan; Forchheimer, Robert; Crispin, Xavier; Facchetti, Antonio; Berggren, Magnus