Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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Now showing 1 - 10 of 1757
  • Article
    Self-Assembled Peptide Hydrogels with Cell Attachment Motifs for 3D Lung Cancer Model: Evaluation of Cell-Matrix Interactions and Drug Response
    (John Wiley and Sons Inc, 2026) Sırma Tarım, B.; Tamburaci, S.; Top, A.
    3D cancer models can mimic the tumor microenvironment, serving as a physiologically relevant platform to investigate the behavior of tumors and test anticancer therapeutics. Although bioactive peptide hydrogels have been widely evaluated for tissue engineering applications, their potential in 3D cancer models has been confirmed in only a few studies. In this study, self-assembling peptide hydrogels containing LDV (IBP1) and LDV and IKVAV cell attachment motifs (IBP2), and the control hydrogel without adhesion units (KLEI) were used for lung cancer modeling. The peptides self-assembled into hydrogels in a cell culture medium with storage moduli of ∼700–1500 Pa. The IBP1 and IBP2 hydrogels enhanced A549 cell proliferation and induced the formation of spheroids with average diameters between ∼70 and ∼150 µm. The cells in KLEI hydrogel with the highest stiffness exhibited mesenchymal-type migration, independent of the cell population, whereas transformation to mesenchymal migration necessitated a specific cell population in the IBP2 hydrogel. The cells in the IBP1 and IBP2 hydrogels with enhanced cell-cell interactions demonstrated higher resistance to docetaxel (DTX). Thus, our results indicate that these bioactive hydrogels can serve as a promising platform for in vitro assessment of cancer mechanisms and drug screening. © 2026 Wiley-VCH GmbH.
  • Article
    Epigallocatechin Gallate and Punicalagin Combination Reduces Aβ Aggregation and Promotes Neurogenesis in Adult Zebrafish Brain
    (John Wiley and Sons Inc, 2026) Nazli, D.; Ipekgil, D.; Poyraz, Y.K.; Can, K.; Okmen, I.; Turhanlar-Sahin, E.; Ozhan, G.
    Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline, memory impairment, and behavioral alterations. The pathogenesis of AD involves the accumulation of amyloid-beta (Aβ) plaques and the hyperphosphorylated tau proteins, which disrupt neuronal function and trigger neuroinflammation. This study explores the therapeutic potential of epigallocatechin gallate (EGCG) and punicalagin (PU) in mitigating Aβ-induced toxicity using an adult zebrafish model of AD. Our results demonstrate that the EGCG + PU combination significantly reduces Aβ accumulation, protects against cellular damage, suppresses acetylcholinesterase (AChE) activity, and normalizes the expression of amyloidogenic and AD-related genes. Additionally, EGCG + PU treatment alleviates neuroinflammation by suppressing glial activation, including reductions in L-plastin and proinflammatory cytokine expression, while promoting neuronal recovery through mechanisms of neurogenesis and neuroprotection. Notably, the combination treatment restored neuronal density and improved behavioral outcomes by alleviating anxiety- and aggression-like behaviors associated with Aβ toxicity. These results underscore the synergistic neuroprotective effects of EGCG + PU, highlighting their potential as a novel therapeutic approach for mitigating the pathological, behavioral, and inflammatory aspects of AD. © 2026 Wiley Periodicals LLC.
  • Article
    Robust CVD Polymer Encapsulation for Thermally and Chemically Resistant Fluorescent Sensor Nanoprobes
    (Elsevier Ltd, 2026) Karabıyık, M.; Cihanoğlu, G.; Ebil, Ö.
    Semiconductor quantum dots (QDs) are attractive fluorophores for sensor applications due to their narrow emission bandwidths and high photostability; however, their performance is often limited by insufficient chemical and thermal durability under operating conditions. In this study, a solvent-free encapsulation strategy based on initiated chemical vapor deposition (iCVD) is proposed to enhance the stability of QD-based sensor nanoprobes. Cross-linked poly (glycidyl methacrylate-co-ethylene glycol dimethacrylate) (ECOP) thin films were conformally deposited as encapsulation layers onto CdTe QD-functionalized poly(GMA) sensor surfaces. The encapsulated nanoprobes were evaluated under chemically aggressive environments (water, salt water, toluene, and sulfuric acid) and elevated temperatures. Following exposure to aggressive solvents, both the polymer film thickness variation and QD fluorescence intensity change remained below 10 %, confirming the robustness of the cross-linked network. Also, thermal durability tests showed stable fluorescence performance after annealing at 250 °C, with structural and optical changes remaining within the accepted 10 % threshold. The results demonstrate that coatings deposited using iCVD exhibit conformal coverage and enhanced stability. This enables reliable protection of QD-based sensor nanoprobes without compromising optical performance. This study presents a promising method to extend the operational lifetime and environmental durability of QD-integrated sensor platforms by using chemically and thermally stable polymer encapsulation. © 2026 Elsevier Ltd
  • Article
    On Group Connected Transmissive Beyond Diagonal RIS for MIMO Systems
    (Institute of Electrical and Electronics Engineers Inc., 2026) Ilguy, M.; Özbek, B.; Le Ruyet, D.
    Reconfigurable intelligent surfaces (RIS) have emerged as an important technology for next-generation wireless networks by intelligently manipulating the wireless propagation environment. Beyond Diagonal RIS (BD-RIS) extends the traditional RIS architecture by allowing non-diagonal reflection matrices, enabling more flexible signal manipulation. Transmissive RIS (T-RIS), on the other hand, facilitates the transmission of signals through the metasurfaces. In this paper, we propose a novel design called transmissive BD-RIS (T-BD-RIS), which integrates the functionalities of BD-RIS and T-RIS to enhance the user data rate. We design an algorithm for the group connected (GC) configuration, which jointly optimizes the beamforming at the base station, the T-BD-RIS transmission matrix, and the receive combiner at the user side. The fully connected (FC) and single connected (SC) cases are special instances of the proposed generic GC design, obtained by an appropriate choice of the number of groups. We evaluate the performance of various schemes, demonstrating the potential of the proposed approach. © 1997-2012 IEEE.
  • Article
    Influence of Innovative Thawing Approaches on the Thermal and Chemical Structure Changes of Frozen Beef Liver
    (Springer, 2026) Avsar, Nazlican; Uzuner, Sibel
    Freezing effectively preserves meat quality, but the formation of ice crystals during the process can impact tenderness and functionality. Thawing is a critical step, as it can lead to physicochemical changes-such as protein oxidation and further ice crystal growth-that may reduce product quality and consumer appeal. Therefore, the thawing method plays a key role in determining the final quality of frozen meat. This study evaluated the physicochemical and structural characteristics of beef liver frozen at - 18 +/- 2 degrees C for 20 h and thawed using three methods: water immersion thawing (WIT), ultrasonic bath thawing (UBT), and air fryer thawing (AFT). No significant differences in drip loss were observed among the UBT, AFT, and WIT samples (p > 0.05). Color measurements (L*, a*, b*) were significantly higher in raw liver than in AFT and UBT samples (p < 0.05). Compared to raw liver and the WIT method, AF and UB thawing lowered the denaturation temperature, indicating reduced thermal stability. The lowest metmyoglobin (MetMb) content was found in the UBT sample (36.57 +/- 0.87%), followed by the AFT sample (41.71 +/- 1.29%), suggesting better pigment preservation with UB thawing. Highlights circle AF and UB thawing methods resulted in a lower denaturation temperature. circle UBT showed the lowest MetMb content, helping to minimize oxidation. circle UBT caused less damage to protein chains and better preserved structural stability. circle UBT preserved desirable aroma characteristics more effectively.
  • Article
    Anticancer Properties of Newly Synthesized Pyrrole Derivatives as Potential Tyrosine Kinase Inhibitors
    (Wiley, 2026) Kaya, Meltem; Kara, Yunus; Sanli-Mohamed, Gulsah
    The anticancer activity of a series of newly synthesized pyrrole derivatives was systematically evaluated in HeLa cervical cancer cells, focusing on their potential as tyrosine kinase inhibitors and modulators of the mTOR signaling pathway. This study builds on our previous synthetic work by investigating the biological effects of seven structurally characterized compounds (d1-d7). Among them, compounds d1 and d3 exhibited the most potent cytotoxicity, with IC50 values of 140.6 mu M and 366.4 mu M, respectively, after 48 h of treatment. Both compounds significantly impaired cell cycle progression-d1 induced S-phase arrest, while d3 caused G1-phase arrest-and markedly suppressed cell migration in wound healing assays. Mechanistically, these effects were accompanied by reduced phosphorylation of p70S6K (Thr389, Ser421/424) and increased p-4EBP1, indicating inhibition of mTORC1 signaling. These findings suggest that d1 and d3 are promising lead compounds with dual antiproliferative and anti-migratory activity in cervical cancer, mediated through modulation of the PI3K/Akt/mTOR axis.
  • Article
    Application of 3D Cell Culture Techniques in Nanotoxicology: How Far Are We
    (Springer, 2026) Shakeri, Raheleh; Mirjalili, Seyedeh Zohreh; Karakus, Ceyda Oksel; Safavi, Maliheh
    Investigation of toxicological profile and possible side effects of engineered nanomaterials (ENMs) is of high importance. Historically, two-dimensional (2D) cell culture was used to study the toxicity of the ENMs, but due to their inability to simulate in vivo cell behavior, three-dimensional (3D) cell culture systems have been developed. Nanotoxicity studies initiate with in vitro experiments and continue with in vivo studies, which are very challenging and sometimes accompanied by conflicting data due to the in vitro-in vivo gap. Thus, scientists are turning their attention to microfabrication techniques and engineered systems "called organ-on-a-chips", which act as an intermediate between in vivo and in vitro systems. The present account tries to review the classical study models and suitably cover the emerging 3D culture models including scaffold-free and scaffold-based 3D cell cultures, 3D co-culture with direct contact and without cell-cell contact methods as well as microfluidic-based tissue chips and organoids. Overall, this review aims to give readers a better insight about the ENMs' toxicology and fill the gaps between the knowledge and practical techniques. Hopefully, the presented information will resolve the issues of 2D in vitro cultures and display the clinically relevant responses to the concerns of therapeutic ENMs.
  • Article
    Liposomal Encapsulation of a Synthetic Bromophenol for Antitumor Efficacy and Apoptotic Activity in Cancer Cells
    (Springer, 2026) Oztanrikulu, Bercem Dilan; Ozdemir, Ekrem; Avci, Bahri; Goksu, Suleyman; Bayrakceken, Handan Uguz; Askin, Hakan
    A novel synthetic bromophenol (BP), inspired by marine-derived natural bromophenols, was evaluated for its antitumor activity and for the enhancement of its in vitro performance through liposomal encapsulation (LipoBP). Etoposide was used as a reference in characterization, release, and loading studies. PEGylated liposomes were employed to improve BP's solubility, bioavailability, and therapeutic potential. The cytotoxicity, apoptosis, and gene expression effects of free BP and LipoBP were assessed in A549 (lung) and MCF-7 (breast) cancer cell lines. WST-8 assays showed that encapsulation significantly increased BP's cytotoxic activity, particularly in A549 cells, while flow cytometry and Annexin V-FITC/PI analyses indicated more pronounced apoptotic induction by LipoBP compared with free BP. qRT-PCR analyses revealed upregulation of proapoptotic genes (BAX, CASP6, CASP3 and CASP9) and downregulation of antiapoptotic/survival genes (BCL-XL, IQSEC2) in both cell lines, indicating activation of intrinsic apoptotic pathways. Plain liposomes exhibited minimal cytotoxicity, confirming their biocompatibility. Liposomal bromophenol, which we have introduced to the literature for the first time, is expected to be a promising nanocarrier system that could be effective in cancer treatment by improving the therapeutic index of new drug candidates such as marine bromophenols.
  • Article
    A Phenomenological Kinetic Flotation Model: Intrinsic Floatability Profiling for Batch and Continuous Flotation Systems
    (Springer Heidelberg, 2026) Polat, Mehmet; Guzel, Veli; Kobas, Muammer; Polat, Hurriyet
    This study presents a mechanistic flotation kinetics model that unifies the description of mineral particle floatability in both batch and continuous systems. Building on a physically explicit interpretation of bubble-particle interactions, the model introduces the concept of intrinsic floatability, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\upphi }_{\text{P},\text{ij}}<^>{\text{s}}$$\end{document}, defined as the size-and composition-dependent probability that a particle within a bubble's sweep volume reports to the froth. A central feature of the framework is that \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\upphi }_{\text{P},\text{ij}}<^>{\text{s}}$$\end{document} is decoupled from system-level rate-determining factors, such as bubble-particle encounter frequency, transport limits, and bubble surface crowding-that otherwise confound attempts to extract floatability distributions from kinetic data. This separation is achieved through three explicit, time-dependent parameters: the encounter rate kappa(t), the limiting flotation rate mu(t), and the bubble saturation factor chi(t). Together, these parameters isolate intrinsic particle behavior from external constraints. The model naturally reduces to the classical first-order rate law in dilute pulps, while in concentrated suspensions it predicts systematic deviations, approaching zero-order kinetics as bubble surfaces saturate. Importantly, the same formulation applies seamlessly to batch tests and multi-stage continuous circuits, enabling a consistent theoretical framework across scales and ore types. Requiring only standard flotation data and known system parameters, the model is practical for both laboratory coal flotation studies and industrial non-coal applications. Validation using batch coal data and continuous plant-scale copper flotation results demonstrates its robustness and broad relevance.
  • Article
    Robust Scheduling of Crude Oil Farming and Processing Under Uncertainty
    (Elsevier, 2026) Yalcin, Damla; Sildir, Hasan
    The sulphur content in crude oil has a significant impact on refinery operations, influencing the feasibility of crude blending, the distribution of product yields, and overall economic performance. Variations in sulphur content introduce uncertainty in the short-term scheduling of crude oil loading, blending, and distillation processes. This study introduces a scenario-based stochastic optimization framework in which sulphur uncertainty is treated as a central modeling element, represented through a regression-based relationship with specific gravity (SG). The approach systematically propagates uncertainty through blending decisions, crude distillation unit (CDU) feed composition, and product yields. The problem is modeled as a mixed-integer quadratically constrained programming (MIQCP) formulation within a continuous-time scheduling framework, enabling the simultaneous optimization of timing, blending, and processing strategies. The results indicate that increased sulphur uncertainty adversely affects the distribution of yields for nine end-products, resulting in profit losses. These findings underscore the importance of explicitly managing compositional uncertainty and provide insights into cost-performance trade-offs in refinery scheduling.