PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7645
Browse
88 results
Filters
Settings
Search Results
Now showing 1 - 10 of 88
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 Application of 3D Cell Culture Techniques in Nanotoxicology: How Far Are We(Springer, 2026) Shakeri, Raheleh; Mirjalili, Seyedeh Zohreh; Karakus, Ceyda Oksel; Safavi, MalihehInvestigation 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 Linking RNA Methylation to Structure: A Biophysical Perspective(Wiley, 2026) Akgul, Bunyamin; Guler, Gunnur; Saglam, Buket; Akkus, Onur; Akcaoz-Alasar, AzimeRecent epitranscriptomic studies show that ribonucleic acids (RNAs) are coated with an array of chemical modifications that dictate their cellular fate. Genetic, biochemical, and genomic approaches have been employed to elucidate the molecular details of RNA methylation, one of the most prevalent types of RNA modifications with significant implications for health and disease. Various biochemical approaches have been developed to identify RNA methylations both at the global and nucleotide resolution levels. However, simpler detection methods are needed to assess the global methylation status of synthetic or cellular RNAs. Although significant progress has been made in elucidating the factors involved in writing, erasing, or reading methylated epitopes or structures, the impact of these methyl moieties on the secondary structure of RNAs or macromolecular interactions remains to be fully understood. Typically, biophysical approaches, such as Fourier transformed-infrared (FT-IR) spectroscopy, circular dichroism (CD), and Raman spectroscopy, have been used to study the structures and interactions of macromolecules, including DNA and proteins. Although RNAs harbor similar chemical modifications or structure-mediated functions, the number of RNA studies that employ biophysical approaches is scarce. In this viewpoint article, we present a biophysical perspective that links RNA methylation to structure and propose that FT-IR analyses can be employed to examine global changes in the abundance of cellular RNA m(6)A marks. Additionally, we discuss the potential applications of biophysical approaches that may be employed to gain insight into methylation-mediated changes in RNA structures.Article Development of Self-Assembled Peptide Hydrogels Containing Matrix-Metalloproteinase Degradable Motifs for 3D Lung Cancer Models(Royal Society of Chemistry, 2026) Tarim, Burcu Sirma; Tamburaci, Sedef; Top, AybenHydrogel-forming peptides, including matrix metalloproteinase (MMP)-degradable motifs, have been employed to investigate cell-extracellular matrix interactions in vitro. However, their potential in 3D cancer models has been explored only in a few studies. In this study, we used modified MMP-2 degradable motifs (VSLRA or ASLRA) in the design of EDP1 (RVSLRADARVSLRADA) and EDP2 (RASLRADARASLRADA) peptide hydrogelators. The peptides self-assembled into nanofibrillar hydrogels with storage moduli between similar to 300 and similar to 400 Pa. MMP-2 degradation properties of the peptides were confirmed, and a slightly higher MMP-2 responsiveness of the EDP1 hydrogel was observed. The hydrogels were used in the encapsulation of A549 lung adenocarcinoma cancer cells and MRC-5 human lung fibroblast cells. The designed hydrogels supported the proliferation of these cells with high viability and induced cluster formation of encapsulated A549 cells similar to that observed with the RADA hydrogel. However, the hydrogel network structure affected the morphology of the migrated cells in the absence of curcumin. The addition of curcumin decreased the migration and invasion of A549 cells, resulting in a round cell morphology independent of the hydrogel matrices. Anticancer drug tests indicated that cell viability after drug treatment was higher in the 3D hydrogels than in 2D cultures. It was also confirmed that the combinational therapy of doxorubicin and curcumin decreased the cell proliferation and colonization to a greater extent compared to doxorubicin monotherapy. Thus, the hydrogels developed in this study can be used for 3D cancer models or other tissue engineering applications as an alternative to the RADA hydrogel by exploiting the MMP-2 degradation properties.Article Enhanced Osteoconductive Properties of Quince Seed Hydrocolloid-Based Composite Scaffolds Enriched With Bioactive Glass for Bone Tissue Engineering(Wiley-VCH Verlag GmbH, 2025) Yilmaz-Dagdeviren, Hilal Deniz; Zheng, Kai; Boccaccini, Aldo Roberto; Arslan Yildiz, AhuBioactive composite scaffolds enhance osteoconduction and mineralization, offering potential for bone regeneration. In this study, polysaccharide-based Quince Seed Hydrocolloid (QSH) was combined with Gelatin (Gel), mesoporous bioactive glass nanoparticles (MBGNs), and 45S5 bioactive glass (BG) to fabricate osteoconductive scaffolds. QSH/Gel/BG and QSH/Gel/MBGN composites were characterized for chemical composition, mechanical behavior, and in vitro bioactivity. FTIR and SEM-elemental mapping confirmed homogeneous bioactive glass incorporation. BET analysis revealed a >3-fold increase in surface area for MBGN-containing scaffolds compared to BG and pristine QSH/Gel samples, attributed to the nanoscale mesoporous structure of MBGNs. Swelling tests showed a hydrophilic nature in all scaffolds, with MBGN composites exhibiting the highest swelling ratio (2094 +/- 571%), nearly twice that of BG composites (1105 +/- 56%). Compression tests indicated similar elastic moduli for MBGN and BG containing scaffolds (2330 and 2140 Pa). Human osteosarcoma cell cultures (28 days) demonstrated high viability (>70%) and osteoconductive response in all composites. Alizarin Red staining and SEM mapping revealed greater mineral accumulation in MBGN-containing scaffolds (Ca/P: 2.53). Overall, both composites supported a 3D osteoconductive microenvironment, while MBGN scaffolds exhibited superior long-term cell viability and mineralization potential, emphasizing their suitability for bone tissue engineering applications.Article Geogenic Determinants of Indoor Radon Exposure in Izmir (West Türkiye)(Pergamon-Elsevier Science Ltd, 2026) Alkan, Turkan; Simsek, Celalettin; Sac, Murat; Uzelli, Taygun; Taskin, NurcihanRadon, a naturally occurring product of uranium decay, is the second leading cause of lung cancer. I(center dot)zmir Province in western T & uuml;rkiye, situated within the Aegean extensional regime, comprises complex fault-bounded basins that favor indoor radon accumulation. This study evaluates the spatial variability and geogenic controls of indoor radon to delineate radon-prone zones with public-health relevance. Indoor radon was measured in 79 dwellings distributed across major lithologies and structural settings; detectors were deployed in basements to capture soil-gas infiltration. Concentrations ranged from 12 to 366.5 Bq/m3 (mean 118 Bq/m3), exceeding the national average of 81 Bq/m3; 32 % of sites surpassed the EPA action level of 148 Bq/m3. Highest values cluster in Bornova, Buca, and Kemalpas, a, coincident with fault-controlled sedimentary basins and permeable units. Spatial mapping highlights the dominant influence of lithology and fault proximity on radon distribution and underscores the limitations of uniform, national-scale mitigation policies. We advocate targeted, geology-aware health policies and urban-planning measures for monitoring and mitigation in geogenically vulnerable districts. These findings contribute to medical geology by providing region-specific evidence of radon risk in one of T & uuml;rkiye's most seismically active metropolitan areas. These outputs provide decision-ready evidence for monitoring, mitigation, and building-code updates in seismically active metropolitan settings.Article Analytical Methodology for Monitoring and Distribution Pattern Analysis of Polycyclic Aromatic Hydrocarbons in River Basins Based on Chemometrics(Wiley, 2025) Yildirim, Ebru calkan; Pelit, Fusun; Ozdemir, Durmus; Kazan, Aysegul; Tasdelen, Ozge; Baycan, NevalWith the increase in urbanization and industrialization, the environmental quality of river basins, which serve as a crucial source of irrigation for agricultural activities, has been deteriorating progressively. Thus, monitoring persistent toxic substances in urban water resources is crucial for maintaining ecological stability and protecting human health. In recent years, particular attention has been directed toward the prevention of polyaromatic hydrocarbons (PAHs), highlighting the importance of analyzing these compounds in water samples through more environmentally sustainable techniques. In this study, we report a green, rapid, cost-effective and simple dispersive liquid-liquid extraction (DLLME) method to monitor PAHs in river waters taken from 21 stations located within the geographical boundaries of the Gediz River Basin in Izmir Province, T & uuml;rkiye. Methodological parameters were optimized by chemometric techniques including Plackett-Burman (PBD) and Box-Behnken design. The method's accuracy was tested upon spiked river samples, and the recoveries ranged from 80% to 102%. The calibration curves were linear, with correlation coefficients greater than 0.98. The limit of detection values were between 0.01 and 0.05 ng mL-1. The reproducibility (RSD%) varied from 4.0% to 19%. Multivariate classification methods such as principal component analysis (PCA) and hierarchical cluster analysis (HCA), along with the supervised classification method partial least squares discriminant analysis (PLS-DA) were applied to elucidate the general distribution patterns of individual PAHs in the basin water samples. The chemometric evaluation conducted across four seasons revealed that PAH contamination was higher in the fall and winter months, resulting in a clear separation from spring and summer samples by using the first two principal components.Article Magnetic Levitation-Based Determination of Single-Nuclei Density(Elsevier, 2026) Anil-Inevi, Muge; Sarigil, Oyku; Unal, Yagmur Ceren; Tekin, H. Cumhur; Mese, Gulistan; Ozcivici, EnginThe biophysical properties of cells and intracellular compartments provide critical insights into their structural and functional states, holding significant potential for biological and medical applications. Single-cell density has recently emerged as a promising biomarker in various research areas, including disease detection, making its precise measurement in biological samples an important analytical objective. Magnetic levitation offers significant advantages over traditional density detection techniques by enabling single-cell analysis rather than bulk measurements, providing precise quantification while preserving natural sample properties and eliminating the need for complex and expensive equipment. While magnetic levitation has been successfully applied to singlecell and cell-aggregate analysis, its use for subcellular compartments remains unexplored. Here, we demonstrate the first application of magnetic levitation technology for the density-based analysis of cell nuclei, a critical organelle essential for genomic preservation and organization. To accommodate the unique size and density characteristics of nuclei compared to whole cells, we systematically investigated appropriate paramagnetic agents, sample loading concentrations, and nuclear equilibrium times required for optimal levitation. We mapped density distributions of nuclei from different cell lines and conducted parallel assessments of cellular and nuclear density changes following cell cycle perturbations and treatments inducing cell death through distinct mechanisms. Our findings establish magnetic levitation as a powerful tool for subcellular density analysis, with potential applications in cell biology research and clinical diagnostics through improved understanding of subcellular physical parameters.Article Citation - WoS: 1The Impact of Oxygen and Antimicrobial Tea Tree Oil Carrying Biomaterial on Cell Viability Under Hypoxic Conditions(Wiley, 2025) Demir, Yagmur Damla; Tepeli, Dilek; Guvensen, Mahmut Deniz; Soyer, Ferda; Akin, Ozlem; Kehr, Nermin SedaTraditional wound treatment involves protecting the wound with dressing and administering antibiotics to prevent tissue infection due to bacteria. However, these methods are inadequate due to the side effects of antibiotics on healthy cells and microbial resistance to antibiotics. Therefore, new strategies involving the application of natural resources such as essential oils as antimicrobial agents in combination with biomaterials as wound dressings have been tested in the treatment of wounds. Furthermore, oxygen (O2)-releasing biomaterials have attracted great interest due to the important role of O2 in wound healing processes. However, the co-application of O2 and essential oil as antimicrobial and cell-promoting agents has not been studied. In this context, we report a novel biomaterial capable of co-delivering O2 and natural antimicrobial tea tree oil (TTO) for 15 and 5 days, respectively. The biomaterial consists of an alginate scaffold (Alg-PMOF-O) containing O2-carrying nanomaterial, laponite and TTO. In vitro bacterial experiments have shown that O2 release from Alg-PMOF-O is an additional parameter acting as an antibacterial agent to inhibit bacterial growth but is not sufficient alone to inhibit bacteria. 5 mu L of TTO in Alg-PMOF-O is necessary to suppress both E. coli and S. aureus over a 1-day incubation period. The effect of TTO and O2 alone or in combination on cell viability is examined using WST-1 and PrestoBlue assays. According to the WST-1 and PrestoBlue tests, the combined application of TTO and O2 does not show any toxic effect on fibroblast cells under normoxic conditions during the 5-day incubation period. Under hypoxic conditions, the WST-1 test shows no toxic effect after only 1 day of incubation, while the PrestoBlue test shows no toxicity under hypoxia during both 1 and 5 days of incubation. On the other hand, the combined application of TTO and O2 indicates toxic effects on cancer Malme-3M cells during both normoxic and hypoxic conditions over 1 and 5 days of incubation. This effect is confirmed by both the WST-1 and PrestoBlue tests. The overall results demonstrate that Alg-PMOF-O exhibits antibacterial activity while having a lower toxic effect on fibroblasts under hypoxic conditions, and therefore has potential for use as wound dressing.