Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.14901/696

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Citation - WoS: 137
Citation - Scopus: 144
Acetylcholinesterase and Carbonic Anhydrase Inhibitory Properties of Novel Urea and Sulfamide Derivatives Incorporating Dopaminergic 2-Aminotetralin Scaffolds
(Pergamon-Elsevier Science Ltd, 2016) Ozgeris, Bunyamin; Goksu, Suleyman; Kose, Leyla Polat; Gulcin, Ilhami; Salmas, Ramin Ekhteiari; Durdagi, Serdar; Supuran, Claudiu T.
In the present study a series of urea and sulfamide compounds incorporating the tetralin scaffolds were synthesized and evaluated for their acetylcholinesterase (AChE), human carbonic anhydrase (CA, EC 4.2.1.1) isoenzyme I, and II (hCA I and hCA II) inhibitory properties. The urea and their sulfamide analogs were synthesized from the reactions of 2-aminotetralins with N,N-dimethylcarbamoyl chloride and N,N-dimethylsulfamoyl chloride, followed by conversion to the corresponding phenols via O-demethylation with BBr3. The novel urea and sulfamide derivatives were tested for inhibition of hCA I, II and AChE enzymes. These derivatives exhibited excellent inhibitory effects, in the low nanomolar range, with K-i values of 2.61-3.69 nM against hCA I, 1.64-2.80 nM against hCA II, and in the range of 0.45-1.74 nM against AChE. In silico techniques such as, atomistic molecular dynamics (MD) and molecular docking simulations, were used to understand the scenario of the inhibition mechanism upon approaching of the ligands into the active site of the target enzymes. In light of the experimental and computational results, crucial amino acids playing a role in the stabilization of the enzyme-inhibitor adducts were identified. (C) 2016 Elsevier Ltd. All rights reserved.
Citation - WoS: 10
Citation - Scopus: 11
Acgc: Adaptive Chrominance Gamma Correction for Low-Light Image Enhancement
(Academic Press Inc. Elsevier Science, 2025) Severoglu, N.; Demir, Y.; Kaplan, N. H.; Kucuk, S.
Capturing high-quality images becomes challenging in low-light conditions, often resulting in underexposed and blurry images. Only a few works can address these problems simultaneously. This paper presents a low- light image enhancement scheme based on the Y-I-Q transform and bilateral filter in least squares, named ACGC. The method involves applying a pre-correction to the input image, followed by the Y-I-Q transform. The obtained Y component is separated into its low and high-frequency layers. Local gamma correction is applied to the low-frequency layers, followed by contrast limited adaptive histogram equalization (CLAHE), and these layers are added up to produce an enhanced Y component. The remaining I and Q components are also enhanced with local gamma correction to provide images with amore natural color. Finally, the inverse Y-I-Q transform is employed to create the enhanced image. The experimental results demonstrate that the proposed approach yields superior visual quality and more natural colors compared to the state-of-the-art methods.
Citation - WoS: 2
Citation - Scopus: 2
Advanced Hybrid Modeling of Cementitious Composites Using Machine Learning and Finite Element Analysis Based on the CDP Model
(MDPI, 2025) Agcakoca, Elif; Jueyendah, Sebghatullah; Yaman, Zeynep; Sumer, Yusuf; Maali, Mahyar
This study aims to investigate the mechanical behavior of cement mortar and concrete through a hybrid approach that integrates artificial intelligence (AI) techniques with finite element modeling (FEM). Support Vector Machine (SVM) models with Radial Basis Function (RBF) and polynomial kernels, along with Multilayer Perceptron (MLP) neural networks, were employed to predict the compressive strength (Fc) and flexural strength (Fs) of cement mortar incorporating nano-silica (NS) and micro-silica (MS). The dataset comprises 89 samples characterized by six input parameters: water-to-cement ratio (W/C), sand-to-cement ratio (S/C), nano-silica-to-cement ratio (NS/C), micro-silica-to-cement ratio (MS/C), and curing age. Simultaneously, the axial compressive behavior of C20-grade concrete was numerically simulated using the Concrete Damage Plasticity (CDP) model in ABAQUS, with stress-strain responses benchmarked against the analytical models proposed by Mander, Hognestad, and Kent-Park. Due to the inherent limitations of the finite element software, it was not possible to define material models incorporating NS and MS; therefore, the simulations were conducted using the mechanical properties of conventional concrete. The SVM-RBF model demonstrated the highest predictive accuracy with RMSE values of 0.163 (R2 = 0.993) for Fs and 0.422 (R2 = 0.999) for Fc, while the Mander model showed the best agreement with experimental results among the FEM approaches. The study demonstrates that both the SVM-RBF and CDP-based modeling approaches serve as robust and complementary tools for accurately predicting the mechanical performance of cementitious composites. Furthermore, this research addresses the limitations of conventional FEM in capturing the effects of NS and MS, as well as the existing gap in integrated AI-FEM frameworks for blended cement mortars.
Citation - WoS: 7
Citation - Scopus: 9
Advanced Mini Solar Still Design: Spiral Heating, Triangular Prism Condensation, and Comprehensive Energy-Exergy Analysis
(Elsevier, 2025) Afshari, Faraz; Kose, Murat; Akyurek, Eda Feyza; Mandev, Emre
Improving solar distillation systems is crucial in addressing water scarcity by providing a sustainable solution for clean water production, while also harnessing renewable energy to reduce environmental impact and reliance on conventional power sources. In solar still systems, salt water is typically contained in a basin, where it is heated by solar energy to produce distilled water through evaporation and condensation procedure. However, traditional systems do not allow for precise control over the temperature of the saltwater. This study introduces a novel approach by integrating a spiral type solar heater for salt water heating, which elevates the saltwater temperature to higher levels. To implement the proposed set up, the integration of a spiral-type solar heater, cotton-based materials, and a perforated pipe for delivering heated saltwater should be adopted, along with intermittent water pump operation to optimize heat absorption and evaporation efficiency. This enhancement enables more efficient condensation, which is achieved using a long triangular prism condensation unit. From the obtained results, it was revealed that the proposed mini solar still system can be modified by using cotton base materials and dripping salt water from a perforated pipe can enhance the distilled water by 138.46%. Comparing the energy efficiency results shows a significant 128.57 % efficiency improvement, highlighting the need to optimize strategies and modifications for better solar distillation performance. Comparing the optimal experiment with the reference experiment revealed a substantial 152.63 % increase in exergy efficiency.
Citation - WoS: 41
Citation - Scopus: 43
Aerobic Exercise Increases Irisin Serum Levels and Improves Depression and Fatigue in Patients with Relapsing Remitting Multiple Sclerosis: A Randomized Controlled Trial
(Elsevier Sci Ltd, 2022) Bilek, Furkan; Cetisli-Korkmaz, Nilufer; Ercan, Zubeyde; Deniz, Gulnihal; Demir, Caner Feyzi
Background: Multiple sclerosis (MS) is a chronic progressive neurodegenerative disease of the central nervous system. Although there is increasing evidence that aerobic exercise has a positive effect on both cognitive and psychological functioning, there is limited evidence for Relapsing-Remitting MS (RRMS) patients. Moreover, it is unclear at what exercise modality and intensity the irisin, the cleaved and circulating form of the exerciseassociated membrane protein Fibronectin Type III Domain Containing 5, is induced in patients with MS. This study aimed to investigate the effect of a regular aerobic exercise program on irisin serum level, depression, fatigue, and cognitive performance in patients with MS. Methods: Thirty-two individuals with RRMS were randomized into 2 groups as control and study groups (mean EDSS score 1.69 and 1.97, respectively). While the Study Group received a combined exercise training consisting of three sessions of aerobic exercise and Frenkel Coordination Exercises per week for 6 weeks, the Control Group received only Frenkel Coordination Exercise training. Before and after the study, the cognitive performance of the participants were evaluated with the Paced Auditory Serial Addition Test with 3-second stimulus (PASAT-3), their maximum aerobic capacity with the Fitmate Pro (R) (VO2max), their fatigue status with the Fatigue Impact Scale (FIS), and their depression status with the Beck Depression Inventory (BDI). Irisin serum levels were analyzed with Enzyme-Linked ImmunoSorbent Assay (ELISA) test from the serum samples of individuals. Results: Our results revealed that the irisin serum level significantly increased in the Study Group. Significant improvement in aerobic capacity, PASAT-3, FIS, and BDI values was observed in the Study Group compared to the Control Group. When the Delta Irisin, Delta VO2max, Delta FIS, and Delta BDI values between the groups were compared, a significant difference was found in favor of the study group. Conclusion: The aerobic exercise revealed significant changes in depression, fatigue and irisin serum levels in MS patients. We think that this study, in which a significant increase in irisin serum level, significant improvement in depression, cognitive performance and fatigue states were obtained in the Study Group, will be a pioneering study for the future studies aiming to investigate the effects of irisin serum level on these symptoms in detail.
Citation - WoS: 6
Citation - Scopus: 10
Affective States Classification Performance of Audio-Visual Stimuli from EEG Signals with Multiple-Instance Learning
(TÜBİTAK Scientific & Technological Research Council Turkey, 2022) Dasdemir, Yaar; Ozakar, Rustem
Throughout various disciplines, emotion recognition continues to be an essential subject of study. With the advancement of machine learning methods, accurate emotion recognition from different data modalities (facial images, brain EEG signals) has become possible. Success of EEG-based emotion recognition systems depends on efficient feature extraction and pre/postprocessing of signals. Main objective of this study is to analyze the efficacy of multiple-instance learning (MIL) on postprocessing features of EEG signals using three different domains (time, frequency, time-frequency) for human emotion classification. Methods and results are presented for single-trial classification of valence (V), arousal (A), and dominance (D) ratings from EEG signals obtained with audio (A), video (V), and audio-video (AV) stimulus using alpha, beta and gamma bands. High accuracy was observed with both binary and multiclass classification of the AV stimulus. Findings in this study suggest that MIL applied on frequency features yields efficient results on EEG emotion recognition.
Citation - WoS: 11
Citation - Scopus: 13
Affinity-Based and In a Single Step Purification of Recombinant Horseradish Peroxidase A2a Isoenzyme Produced by Pichia Pastoris
(Springer, 2023) Acar, Melek; Abul, Nurgul; Yildiz, Seyda; Taskesenligil, Ezgi Dag; Gerni, Serpil; Unver, Yagmur; Ozdemir, Hasan
Horseradish peroxidase (HRP) is an oxidoreductase enzyme and oxidizes various inorganic and organic compounds. It has wide application areas such as immunological tests, probe-based test techniques, removal of phenolic pollutants from wastewater and organic synthesis. HRP is found in the root of the horseradish plant as a mixture of different isoenzymes, and it is very difficult to separate these enzymes from each other. In this regard, recombinant production is a very advantageous method in terms of producing the desired isoenzyme. This study was performed to produce HRP A2A isoenzyme extracellularly in Pichia pastoris and to purify this enzyme in a single step using a 3-amino-4-chloro benzohydrazide affinity column. First, codon-optimized HRP A2A gene was amplified and inserted into pPICZ alpha C. So, obtained pPICZ alpha C-HRPA2A was cloned in E. coli cells. Then, P. pastoris X-33 cells were transformed with linearized recombinant DNA and a yeast clone was cultivated for extracellular recombinant HRP A2A (rHRP A2A) enzyme production. Then, the purification of this enzyme was performed in a single step by affinity chromatography. The molecular mass of purified rHRP A2A enzyme was found to be about 40 kDa. According to characterization studies of the purified enzyme, the optimum pH and ionic strength for the rHRP A2A isoenzyme were determined to be 6.0 and 0.04 M, respectively, and o-dianisidine had the highest specificity with the lowest Km and Vmax values. Thus, this is an economical procedure to purify HRP A2A isoenzyme without time-consuming and laborious isolation from an isoenzyme mixture.
Citation - WoS: 9
Citation - Scopus: 10
Altitude Control of Quadcopter with Symbolic Limited Optimal Discrete Control
(Springer Nature, 2024) Ozbaltan, Mete; Caska, Serkan
In recent years, quadcopter UAVs have been extensively utilized. Controlling quadcopters is a major concern, and researchers are actively studying it. In this study, altitude control of a quadcopter UAV is achieved using the symbolic limited optimal discrete controller synthesis technique. The resulting controller is compared with the adaptive PID control method, where the PID controller's parameters are determined using the Dragonfly algorithm. The findings show the superior performance of our approach.
Citation - WoS: 2
Citation - Scopus: 3
Analysing Instability as a Future for an Institutionalization Process: The EU, Turkey and the Issue of Migration
(Springer, 2018) Kaplan, Yilmaz
This article argues that migration has evolved into a conflictual parameter in the institutionalization of the EU-Turkey relationship and that it plays a significant role in the formation of instability as the main feature of this institutionalization process. Moreover, migration in its nature is a dynamic/non-linear social phenomenon which makes an institutionalization process highly open to exogenous effects and quite unstable. Therefore, contrary to the mainstream institutionalist approaches, this case study argues that an institutionalization process does not necessarily bring about continuity in the wake of an exogenous shock, but if an institutionalization process contains conflictual parameters (like the migration issue) with a strong connection with endogenous and exogenous dynamics, instability/change might become the main feature of it. From this point of view, this study anticipates that the migration-like dynamic parameters will keep the European integration as an ongoing process in the future, and its structure will be subject to a continual change. Furthermore, this change-oriented institutionalization might make the EU more heterogeneous and multi-dimensional in time. Related to this anticipation, even though the migration issue plays an inhibitor role in Turkey's accession process to the EU at the moment, it might play a catalyst role in this process by making a differentiated membership a more reasonable option for both the EU countries and Turkey in a more differentiated EU structure in the future.
Analysing Traffic Accidents in Terms of Driver Violation Behaviour Types: Machine Learning and Sensitivity Analysis Approaches
(Wiley, 2025) Kuskapan, Emre; Codur, Muhammed Yasin; Dissanayake, Dilum
Traffic accidents have become a major concern for governments, organizations and individuals worldwide due to the material and moral losses they cause. It is possible to reduce this concern by taking into account the research conducted by relevant institutions and organizations in this field. The main objective of this study is to categorize traffic accidents according to driver violation types and analyse them using machine learning algorithms and feature sensitivity to identify the most influential variables in each category. For this purpose, traffic accident reports that occurred in Erzurum province in the last 1 year were used to categorize and classify driver violation behaviour types. Five different machine learning algorithms, namely k-nearest neighbour, support vector machines, naive Bayes, multilayer perception and random forest, were used to examine the success performance of the classification. Among these, 91% successful classification was obtained with the random forest algorithm. Based on the classification obtained from this algorithm, sensitivity analysis was used to reveal the variables that most affect each violation category. The results of the analysis revealed that driver age and vehicle type were the most influential variables for many types of violations. Thanks to this study, the problems were clearly identified by going into the details of driver violation behaviours. At the end of the study, measures to reduce driver violation behaviours were proposed. If the recommendations that can reduce driver behaviour are taken into consideration by transportation authorities and policy makers, traffic accidents can be significantly reduced.
Citation - WoS: 8
Citation - Scopus: 10
Analysis of Mixed Convection Heat Transfer of Nanofluids in a Minichannel for Aiding and Opposing Flow Conditions
(Springer, 2019) Manay, Eyuphan; Mandev, Emre; Temiz, Resul Onder
In this study, mixed convection heat transfer characteristics of nanofluid flow in a circular minichannel were investigated experimentally. The effects of the particle volume ratio (0, 0.25, and 0.75%) and Reynolds number (200-60) on heat transfer by mixed convection were investigated for aiding and opposing flow conditions. Water and water based SiO2 nanofluids were used as working fluid in a minichannel with a diameter of 1.9 mm, and constant heat flux was applied to the outer surface of the minichannel. Temperature-dependent thermophysical properties such as thermal conductivity and viscosity, obtained by experimental measurements, were used in heat transfer calculations. Pressure based numerical computations for all experimental cases were also made by using single phase approach. The results were analyzed separately for aiding flow condition in which secondary flows originating from natural convection are in the same direction with the forced flow, and for opposing flow condition in which secondary flows are in the opposite direction with forced flow. For detailed analysis of mixed convection heat transfer, temperature contours and velocity profiles were obtained by the numerical computations which were compared and validated with the experimental results. According to the data obtained, it was determined that the addition of nanoparticles into the pure water increased the Nusselt number by around 21-64% for the aiding flow, and 18-58% for the opposing flow. The heat transfer in the aiding flow was observed to be minimum 4% and maximum 16% higher in comparison with the opposing flow condition. It was concluded that the direction of secondary flows significantly affects heat transfer.
Citation - WoS: 12
Citation - Scopus: 12
Analysis of the Effect of Rock Salt on Grout’s Freeze-Thaw Strength with the Taguchi Method
(Elsevier, 2022) Zaimoglu, Ahmet Sahin; Kilic, Elif Ayik; Artuk, Fatih
Grouting is the injection of mixtures with high pressure into the voids, cracks, or pores that may exist in the soil. In the case of rock salt being present in the formations where the grouting is performed, studies on the effects of this salt presence on the freeze-thaw strength of the grout are rare in the literature. The Taguchi Method was used to assess the effect of rock salt on the freeze-thaw strength of grouts in this research (at 0, 50, and 100 freeze -thaw cycles). For the experimental design, a 3-parameter and a 4-level experimental design table were employed following the Taguchi Method. In the Taguchi Method, water/cement ratio (W/C), sand percentage (SP), and saturation percentage with rock salt (SPRS) were chosen as experimental parameters. The levels of these pa-rameters were determined as 0.8-1.0-1.2-1.4; 0%-25%-50%-100%; and 0%-25%-50%-100%, respectively. The freeze-thaw strength of the prepared grout samples at 0, 50, and 100 cycles were determined. As a result of the experiments, it was determined that the strength of 50 cycles of grout samples increased by up to the 2nd level (25%) of SPRS. The 0 and 100 freeze-thaw strength decreased with the increase in SPRS. Pertaining to all prepared grout samples, freeze-thaw strength decreased when W/C increased and rose as SP increased in general.
Citation - WoS: 3
Citation - Scopus: 3
An Analytical Method to Visualize Higher Mode Effects on Yielding Cantilever Walls
(Wiley, 2021) Kazaz, Ilker
A nonlinear flexural plastic hinge developing at the base of the cantilever wall changes its dynamic properties. In such systems, contribution of higher modes to the total shear force response after yielding may be underestimated when they are assumed to prone same or some nonlinearity as the first mode. In order to calculate the modal properties of a cantilever walls developing a plastic hinge at the base after yielding, the fundamental analytical beam formulation is revisited, and by applying special boundary condition reflecting the nonlinear deformation at the fixed base, that is, plastic hinge rotation, a novel formulation that is able to track changes in the modal properties of yielding cantilever shear wall is derived. The modal properties are effectively calculated depending on the level of nonlinear plastic rotation demand. Derived formulation can be very useful in the analysis of higher mode effects on shear wall systems, where the essential understanding of dynamic shear force amplification in cantilever wall system lays in the variation of the systems dynamic modal properties extending from linear to nonlinear range. A mode superposition method using equivalent nonlinear modal single-degree-of-freedom (SDOF) systems is presented for the estimation of maximum shear force.
Citation - WoS: 14
Citation - Scopus: 17
Analyzing Key Socio-Economic and Socio-Demographic Drivers of Domestic Passengers' Airline Choice Behavior in Turkey Using Multinomial and Mixed Logit Models
(Taylor & Francis Ltd, 2016) Yaylali, M.; Celik, A. K.; Dilek, O.
The main objective of this paper is to determine the key factors affecting passengers' domestic airline choice in Turkey. This study utilized thedata of a self-administeredsurvey conducted to 2473 passengers in 11 different airports. The data were analyzed using multinomial and mixed logit (ML) models. The analysis results reveal that ML model is useful to explain preference heterogeneity of passengers' airline choice behavior. The estimation results also indicate that several demographic, socio-economic, and travel destination characteristics were found as the significant drivers of passengers' airline choice. The results of this study may be a valuable tool for policy-makers in the airline industry.
Citation - WoS: 5
Citation - Scopus: 4
Analyzing of Bolted Joints for Connecting Rectangular Hollow Sections in Reticulated Shells
(Taylor & Francis Ltd, 2023) Maali, Mahyar; Orhan, Suleyman Nazif; Sagiroglu, Merve; Cirpici, Burak Kaan
This paper investigates a novel joint method for connecting rectangular hollow section (RHS) members in reticulated shells. It is proposed to overcome the problem of connecting rectangular tubes using the traditional joint (cast steel joint) under dead and snow load. A case study is a structure in the eastern region of Turkey that was built on August 20, 2019. This museum-style structure is 40 meters long and 20 meters wide, with an oval shape. In the middle of the building, five tree-shaped columns were used. ANSYS is used to create a refined 3D solid model of the RHS joint. The moment-rotation results show that the proposed RHS joint (plate steel joint) for connecting rectangular hollow section members can be considered a semi-rigid connection and preferred due to its lower cost and weight. Moreover, the dissipated energy capacity has been raised by approximately 3.22 times when the plate steel type model has been used instead of the cast steel type. The stress ratios indicate that the connection stress in the Cast steel type model is lower than the stress in the Plate steel type model. As a result, the Cast steel type model is determined to be incredibly safe and more rigid than plate steel. Furthermore, since the resulting stress rates are lower than those of S355 steel, both models (cast and plate steel type models) can be used for connecting RHS.
Citation - WoS: 29
Citation - Scopus: 30
Antibacterial Activity and Chemical Composition of Essential Oil Obtained from Nepeta Nuda Against Phytopathogenic Bacteria
(Taylor & Francis Inc, 2013) Gormez, Arzu; Bozari, Sedat; Yanmis, Derya; Gulluce, Medine; Agar, Guleray; Sahin, Fikrettin
The increase in agricultural production can be possible with the discovery and utilization of chemical compounds for plant disease control. However, indiscriminate use of chemical compounds against microorganisms causes many negative side effects on environment and mammalian health. Therefore, we aimed to find a new natural antimicrobial product from medicinal plants against phytopathogenic bacteria. In this study, the essential oil (EO) of Nepeta nuda was isolated by the hydrodistillation method and the chemical composition of the EO was analyzed by gas chromatography-mass spectrometry (GC-MS), as its biological activity was connected to its content. Then, the antibacterial property of EO was evaluated against twenty phytopathogenic bacteria. Nepeta contains 4a,7,7a-nepetalactone (18.10%), germacrene (15.68%), elemol (14.38%), -caryophyllene (8.81%), spathulenol (6.14%) and cubenol (5.10%) as major components. In conclusion, the present study is valuable for future investigations on controlling plant pathogenic bacteria.
Citation - WoS: 7
Citation - Scopus: 7
Antibacterial Activity and Cytotoxicity of Bioinspired Poly (L-Dopa) Silver Nanostructure-Decorated Titanium Dioxide Nanowires
(Elsevier, 2022) Serginay, Nuray; Dizaji, Araz Norouz; Mazlumoglu, Hayrunnisa; Karatas, Erkan; Yilmaz, Asli; Yilmaz, Mehmet
The combination of silver (Ag) and titanium dioxide (TiO2) nanostructures offer unique advantages in terms of elimination of infection and enhanced antibacterial activity with relatively higher biocompatibility and lower cytotoxicity. Although there have been numerous attempts for the fabrication of these nanocomposite systems, novel, flexible, low-cost, simple, effective, reducing, and stabilizing agent-free strategies are highly required for biomedical applications. Within this context, we report the employment of silver nanostructure decorated TiO2 nanowires (TiO2 NWs) as an ideal antibacterial agent against antibiotic-resistant Gram-negative (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus). Firstly, TiO2 NWs were fabricated via the hydrothermal procedure. Afterward, by utilizing the oxidative polymerization of 3,4-dihydroxyphenyl-L-alanine (L-DOPA), a conformal and thin polymer layer of L-DOPA (PLDP) was created onto the TiO2 NWs (TiO2/PLDP). Lastly, Ag nanostructures were deposited onto the TiO2/PLDP (TiO2/PLDP/Ag NP) via simply reduction of silver ions. Herein, PLDP with its abundant catechol and amine groups played an important role in the reduction of silver ions and the adsorption of Ag nanostructures with high affinity and resultant stability. The size, density, and morphology of Ag nanostructures were manipulated by tuning the initial amount of Ag ions in a well-controlled manner. The resultant colloidal TiO2/PLDP/Ag composite nanosystem provided remarkably high and stable antibacterial activity against both antibiotic-resistant bacteria strains. Minimum Inhibitory Concentration (MIC) values were found to be 125, 250, and > 500 ppm for high, medium and, low deposition of Ag nanostructures, respectively. Similarly, Minimum Bactericidal Concentration (MBC) for these NP systems, MBC values were found to be 250, 500, and > 1000 ppm, respectively. Also, relatively lower cytotoxicity in human lung healthy (MRC5) and cancer (A549) cell lines was detected in a dose-dependent manner in comparison to the citrate-stabilized Ag nanoparticles. The proposed novel TiO2/PLDP/Ag nanosystem will provide unique opportunities in terms of flexibility, low-cost, simplicity with reducing, and stabilizing agent-free strategy and be employed in the removal of biofilms and anti-inflammatory effects.
Citation - WoS: 9
Citation - Scopus: 9
Anticancer Effects of Novel NSAIDs Derivatives on Cultured Human Glioblastoma Cells
(Walter de Gruyter GmbH, 2021) Ozdemir, Ozlem; Marinelli, Lisa; Cacciatore, Ivana; Ciulla, Michele; Emsen, Bugrahan; Di Stefano, Antonio; Turkez, Hasan
Several epidemiologic, clinical and experimental reports indicate that nonsteroidal anti-inflammatory drugs (NSAIDs) could have a potential as anticancer agents. The aim of this study was the evaluation of cytotoxic potential in human glioblastoma cells of novel synthesized NSAID derivatives, obtained by linking, through a spacer, alpha-lipoic acid (ALA) to anti-inflammatory drugs, such as naproxen (AL-3, 11 and 17), flurbiprofen (AL-6, 13 and 19) and ibuprofen (AL-9, 15 and 21). The effects on the level of gene expression were also determined using quantitative real-time polymerase chain reaction (qRT-PCR) analysis. According to our results, NSAID derivatives exhibited concentration dependent cytotoxic effects on U87-MG cell line when compared with the control group. Moreover, treatment of the most active compounds (AL-3, AL-6 and AL-9) caused upregulation of tumor suppressor gene PTEN and downregulation of some oncogenes such as AKT1, RAF1 and EGFR. In conclusion, our results revealed that AL-3, AL-6 and AL-9 could be suitable candidates for further investigation to develop new pharmacological strategies for the prevention of cancer.
Citation - WoS: 2
Citation - Scopus: 2
Anticancer Potential of Novel Cinnamoyl Derivatives Against U87mg and SHSY-5Y Cell Lines
(Bentham Science Publishing Ltd, 2024) Gouleni, Niki; Di Rienzo, Annalisa; Oner, Sena; Karagoz, Ceren; Arslan, Mehmet Enes; Mardinoglu, Adil; Cacciatore, Ivana
Background Glioblastoma multiforme (GBM) is probably the most malignant and aggressive brain tumor belonging to the class of astrocytomas. The considerable aggressiveness and high malignancy of GBM make it a tumor that is difficult to treat. Here, we report the synthesis and biological evaluation of eighteen novel cinnamoyl derivatives (3a-i and 4a-i) to obtain more effective antitumor agents against GBM.Methods The chemical structures of novel cinnamoyl derivatives (3a-i and 4a-i) were confirmed by NMR and MS analyses. The physicochemical properties and evaluation of the ADME profile of 3a-i and 4a-i were performed by the preADMETlab2.0 web program. Cinnamoyl derivatives 3a-i and 4a-i were tested in vitro for their cytotoxicity against the human healthy fibroblast (HDFa) cells using an MTT cell viability assay. Derivatives with no toxicity on HDFa cells were tested both on human glioblastoma (U87MG) and neuroblastoma (SHSY-5Y) cells, chosen as an experimental model of brain tumors. Cell death mechanisms were analyzed by performing flow cytometry analyses.Results Cinnamoyl derivatives 3a-i and 4a-i showed good physicochemical and ADME properties suggesting that these compounds could be developed as oral drugs endowed with a high capability to cross the blood-brain barrier. Compounds (E)-1-methoxy-4-(2-(phenylsulfonyl)vinyl)benzene (2c) and (E)-N-benzyl-N-(2-(cyclohexylamino)-2-oxoethyl)-3-(3,4,5-trimethoxyphenyl)acrylamide (3e) did not show cytotoxicity on healthy human fibroblast cells up to 100 mu g/mL. The most anticarcinogenic molecule, compound 3e, emerged as the most potent anticancer candidate in this study. Flow cytometry results showed that compound 3e (25 mu g/mL) application resulted in nearly 86% and 84% cytotoxicity in the U87MG and the SHSY-5Y cell lines, respectively. Compound 2c (25 mu g/mL) resulted in 81% and 82% cytotoxicity in the U87MG and the SHSY-5Y cell lines, respectively.Conclusion Cinnamoyl derivative 3e inhibits the proliferation of cultured U87MG and SHSY-5Y cells by inducing apoptosis. Further detailed research will be conducted to confirm these data in in vivo experimental animal models.
Citation - WoS: 137
Citation - Scopus: 135
Antioxidant Activity, Acetylcholinesterase, and Carbonic Anhydrase Inhibitory Properties of Novel Ureas Derived from Phenethylamines
(Wiley-V C H Verlag GmbH, 2016) Aksu, Kadir; Ozgeris, Bunyamin; Taslimi, Parham; Naderi, Ali; Gulcin, Ilhami; Goksu, Suleyman
A series of ureas derived from phenethylamines were synthesized and evaluated for human carbonic anhydrase (hCA) I and II, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzyme inhibitory activities and antioxidant properties. The ureas were synthesized from the reactions of substituted phenethylamines with N,N-dimethylcarbamoyl chloride; then, the synthesized compounds were converted to their corresponding phenolic derivatives via O-demethylation. hCA I and II were effectively inhibited by the newly synthesized compounds, with K-i values in the range of 0.307-0.432nM for hCA I and 0.149-0.278nM for hCA II. On the other hand, the K-i parameters of these compounds for AChE and BChE were determined in the range of 0.129-0.434 and 0.095-0.207 nM, respectively. Phenolic ureas also showed good antioxidant activities.

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