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 - 8 of 8
  • Article
    Dissecting the Metabolic Landscape of Breast Cancer Subtypes via Elastic Net Modeling and Examining Its Immune Correlates
    (Walter de Gruyter GmbH, 2026) Kus, M.E.; Ekiz, H.A.
    Objectives: Breast cancer is a heterogeneous disease, and the estrogen receptor (ER) status is a key factor in disease classification and treatment planning. While metabolomic profiling has revealed subtype-specific differences, cross-study comparisons have been limited, posing challenges for data extrapolation. This study aims to investigate metabolites that differentiate ER-positive and ER-negative tumors via integrative analyses of multi-omics data. Methods: We jointly analyzed two untargeted metabolomics datasets via elastic net modeling using consistent analysis pipelines tuned for low sample sizes, namely multiple bootstrapping and stability selection. Significant metabolite predictors from two studies were cross-examined to reveal distinctions and commonalities. We also performed differential gene expression analysis using RNA sequencing data from matching samples to link metabolic patterns with transcriptomic signatures and intratumoral immune cell signatures. Results: This study identified unique metabolite signatures in distinct datasets and a limited overlap of discriminating metabolites that can be broadly generalizable for subtyping. Nevertheless, several glycolysis and fatty acid metabolism intermediates exhibited variation depending on the tumor ER status. Consistently, genes related to fatty acid metabolism and glycolysis were enriched in ER-positive and ER-negative tumors respectively. Furthermore, we used multiple immune cell deconvolution algorithms to correlate various immune cell types with the metabolite levels within the tumor microenvironment. Conclusions: Together, these findings highlight the metabolic and immunological diversity of breast cancer and establish a reproducible machine-learning framework for integrating multi-omics data to interrogate tumor complexity. © 2025 the author(s), published by De Gruyter, Berlin/Boston.
  • Article
    Development and Evaluation of 177Lu-Imatinib: Radiolabeling and Cell Culture Studies
    (Walter de Gruyter GmbH, 2025) Ozgenc, E.; Karpuz, M.; Guler, G.; Burak, Z.; Başpainar, Y.; Gundogdu, E.A.
    Targeted radiopharmaceuticals offer promising approaches for cancer diagnosis and therapy. This study developed freeze-dried kit formulations of 177Lu-Imatinib (IMT) and evaluated their potential efficacy through in vitro studies. Four formulations (F1-F4) containing IMT and chelating agents were prepared and characterized via Fourier transform infrared (FTIR), ultraviolet spectrum (UV), and thermogravimetric analysis (TGA) to confirm complex formation. Biocompatibility was assessed in NIH-3T3 cells using the MTT assay. Radiolabeling with 177Lu was optimized by varying pH, incubation time, and reactant ratios. Radiochemical purity and stability were analyzed over 7 days using HPLC. Binding affinity and cytotoxicity were evaluated in MCF-7 and NIH-3T3 cells. Spectroscopic analyses confirm successful complex formation. All formulations exhibited >90% viability in NIH-3T3 cells. Optimal radiolabeling conditions (45mg IMT-chelator, pH 5, 60min incubation) yielded >90% efficiency, with stable radiolabeling for 7 days. The 177Lu-IMT-DOTA (F3) formulation showed significantly higher binding and cytotoxic effects in MCF-7 cells compared to controls. The 177Lu-IMT-DOTA (F3) kit demonstrates high radiolabeling efficiency, stability, and selective in vitro cytotoxicity toward breast cancer cells, supporting its potential as a targeted radiopharmaceutical. © 2025 Walter de Gruyter GmbH, Berlin/Boston 2025.
  • Article
    Gypsophila Eriocalyx Roots Inhibit Proliferation, Migration, and Tgf-Β Signaling in Melanoma Cells
    (Walter de Gruyter GmbH, 2025) Azbazdar, Yagmur; Ozhan, Gunes; Helvacioglu, Selin
    Objectives: Melanoma is a highly malignant and serious form of skin cancer. In addition to the standard treatments, complementary approaches, including phytotherapy, are also used to alleviate symptoms and improve patient well- being. This study aims to investigate the anticancer effects of Gypsophila eriocalyx (GE), an endemic species from Türkiye, on melanoma cells. We set out to determine the efficacy of GE in inhibiting melanoma cell proliferation, migration, and growth, and to explore its underlying mechanisms. Methods: We examined the impact of GE on the prolifera- tion of two melanoma cell lines, Malme-3M and SK-MEL-28, and assessed its developmental toxicity in zebrafish em- bryos. Next, we evaluated GE’s influence on colony forma- tion and wound healing in melanoma cells, as well as its ability to induce apoptosis and affect the TGF-β/Smad signaling pathway, by measuring pathway reporter activity and target gene expression. Results: GE inhibited cell proliferation in melanoma cell lines at concentrations 104 to 488 times lower than those required for normal non-malignant L929 fibroblast cells. In zebrafish embryos, GE demonstrated developmental toxicity only at concentrations above 50 μg/mL. GE treatment significantly impaired the colony formation and wound healing abilities of melanoma cells, indicating reduced pro- liferation and migration. Moreover, GE induced apoptosis in melanoma cells and inhibited the TGF-β/Smad signaling pathway, as evidenced by decreased pathway reporter activity and target gene expression. Conclusions: This study highlights the potential of GE as a novel therapeutic agent in melanoma treatment by demon- strating its ability to inhibit tumor growth and progression
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Assessment of the Validity and Reliability of Edinburgh Postpartum Depression Scale in Turkish Men
    (Walter de Gruyter GmbH, 2024) Alkan, C.; Didikoǧlu, A.; Çöme, O.; Yllmaz, B.; Mevsim, V.
    Objectives: Perinatal depression (PD) affects individuals during pregnancy and early parenthood, resembling major depression. Recent research highlights paternal perinatal depression (PPD) in fathers. PPD has adverse effects on fathers and their children. This study assesses the Turkish version of the Edinburgh Postnatal Depression Scale (EPDS) for Turkish fathers, aiming to provide a tool for PPD identification. Methods: This methodological study validates the EPDS for Turkish fathers and explores associations with demographic and psychosocial factors. The study involved 295 fathers with infants aged 2 weeks to 12 months. The EPDS, originally designed for perinatal depression and validated in Turkish women, was used. Fathers completed a participant information questionnaire, the EPDS, and the Beck Depression Inventory (BDI) during clinic visits. Data on sociodemographic factors, paternal roles, and pregnancy and postpartum support were collected. Mothers also completed the EPDS. Descriptive statistics, exploratory factor analysis, confirmatory factor analysis, and correlation tests were used. Results: The study included fathers with an average age of 30.5 years, mostly with a high school education or higher. The EPDS had a mean total score of 3.1. Factor analysis suggested a three-factor structure for the EPDS in Turkish fathers, including anhedonia, anxiety, and depression. Confirmatory factor analysis validated the three-factor structure, with acceptable model fit indices. Positive correlations were found between fathers' EPDS scores, maternal EPDS scores, and paternal BDI scores. The EPDS effectively discriminated between different levels of depression severity. Various factors, such as education level and lack of support during pregnancy and after childbirth, were associated with higher EPDS scores. Conclusions: These findings emphasize the significance of assessing and addressing PPD in fathers, supporting the use of the EPDS as a valid tool in the Turkish context. The three-factor structure aligns with international research, highlighting the importance of a multi-dimensional approach to PPD assessment. Early intervention can mitigate PPD's impact on fathers, mothers, and children, benefiting mental health and well-being. © 2024 Walter de Gruyter GmbH, Berlin/Boston.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 4
    Influence of Partitioning Treatment on Microstructure and Mechanical Properties of an Alloyed Ductile Iron Austempered at Different Temperatures
    (Walter de Gruyter GmbH, 2023) Neite, Maximilian; Münstermann, Sebastian; Nalçacı, Burak; Davut, Kemal; Erdoğan, Mehmet
    The present study was conducted to uncover effects of partitioning treatment on Cu-Ni-Mo alloyed ductile iron (DI) austempered at different temperatures. For this purpose, the DI samples, produced via sand casting, were austenitized at 900 °C for 60 min, followed by austempering at the temperatures of 275-325-375 °C for 120 min and afterwards a partitioning treatment was applied at 200 °C for 15 min. In the characterization studies, dilatometer, image analysis, JMat-Pro, mechanical tests, XRD, optical microscope, and scanning electron microscope (SEM) equipped with EBSD detector were utilized. Characterization studies showed that the effects of partitioning treatment were directly correlated with austempering temperature and high carbon austenite volume fraction changed in the range of 19.48-35.45%. That redistribution of carbon (C) between bainitic ferrite and high carbon austenite occurred, in turn, the carbon content of high carbon austenite increased with the partitioning treatment irrespective of austempering temperature were uncovered. Furthermore, the partitioning treatment considerably changed the grain morphologies of both high carbon austenite and banitic ferrite. As a consequence of these microstructural differences, the highest tensile strength of 1489.2 MPa was established in the sample austempered at 275 °C and partitioned at 200 °C, whereas the highest ductility of 5.61% acquired at the austempering temperature of 375 °C. © 2023 Walter de Gruyter GmbH, Berlin/Boston.
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    Nondestructive Microstructural Characterization of Austempered Ductile Iron
    (Walter de Gruyter GmbH, 2023) Tüzün, Mert Yağız; Yalçın, Mustafa Alp; Davut, Kemal; Kılıçlı, Volkan
    Austempered ductile iron (ADI) has been preferred in a wide range of applications due its unique combination of high strength, good ductility, wear resistance and fracture toughness together with lower cost and lower density compared to steels. Magnetic Barkhausen noise (MBN) measurement offers a better alternative to traditional characterization techniques by being fast and non-destructive. A simple linear regression using only one single independent variable cannot correlate the MBN with the microstructure of ADI, since its microstructure is multi component. Multiple linear regression analysis (MLRA) was used to build a model that uses the characteristic features of microstructural constituents as input parameters to predict the MBN. For that purpose, Cu-Ni-Mo alloyed ductile iron samples austempered between 325 and 400 degrees C and for 45-180 min duration were used. The results show that MBN is most sensitive to the size and shape of acicular ferrite and retained austenite. Moreover, MBN is almost insensitive to the size, morphology and volume fraction of graphite particles. This indicates that retained austenite pins the domain walls more effectively than the graphite particles. Considering the results MLRA, MBN technique can be used to characterize the ausferritic microstructure of ADI.
  • Article
    Citation - WoS: 22
    Citation - Scopus: 22
    Simultaneous Validation of Wearable Motion Capture System for Lower Body Applications: Over Single Plane Range of Motion (rom) and Gait Activities
    (Walter de Gruyter GmbH, 2022) Mihçin, Şenay
    Extracting data from {Zhu, 2019 #5} daily life activities is important in biomechanical applications to define exact boundary conditions for the intended use-based applications. Although optoelectronic camera-marker based systems are used as gold standard tools for medical applications, due to line-of-sight problem, there is a need for wearable, affordable motion capture (MOCAP) systems. We investigate the potential use of a wearable inertial measurement unit (IMU) based-wearable MOCAP system for biomechanical applications. The in vitro proof of concept is provided for the full lower body consisting of hip, knee, and ankle joints via controlled single-plane anatomical range of motion (ROM) simulations using an electrical motor, while collecting data simultaneously via opto-electronic markers and IMU sensors. On 15 healthy volunteers the flexion-extension, abduction-Adduction, internal-external rotation (ROM) values of hip and, the flexion-extension ROM values of the knee and ankle joints are calculated for both systems. The Bland-Altman graphs showed promising agreement both for in vitro and in vivo experiments. The maximum Root Mean Square Errors (RMSE) between the systems in vitro was 3.4° for hip and 5.9° for knee flexion motion in vivo, respectively. The gait data of the volunteers were assessed between the heel strike and toe off events to investigate the limits of agreement, calculating the population averages and standard deviation for both systems over the gait cycle. The maximum difference was for the ankle joint <6°. The results show that proposed system could be an option as an affordable-democratic solution.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 5
    Effects of Tib2 Nanoparticle Content on the Microstructure and Mechanical Properties of Aluminum Matrix Nanocomposites
    (Walter de Gruyter GmbH, 2017) Kandemir, Sinan
    The present work reports the fabrication of A357 alloy matrix nanocomposites reinforced with 0.5, 1.0 and 2.0 wt.-% TiB2 nanoparticles (20-30 nm) by a novel method which is the combination of semi-solid mechanical mixing and ultrasonic dispersion of nanoparticles in liquid state. The microstructural and mechanical properties of the fabricated nanocomposites were investigated. The microstructural studies conducted with optical and advanced electron microscopes indicated that reasonably effective deagglomeration and uniform distribution of TiB2 nanoparticles into the matrix were achieved. Transmission electron microscopy studies also confirmed that the nanoparticles were embedded into the matrix and a good bonding was obtained between the matrix and the reinforcement. Increasing nanoparticle content led to grain refinement and significant enhancement in the mechanical properties of nanocomposites. The addition of 0.5, 1.0, and 2.0 wt.-% TiB2 nanoparticles increased the 0.2 % proof stress of matrix alloy by approximately 31, 48 and 61 %, respectively. The contribution of different mechanisms to the strength enhancement is discussed. It is proposed that the strengthening is mainly due to Orowan mechanism and dislocation generation effect by the coefficient of thermal expansion mismatch between the TiB2 nanoparticles and the matrix.