PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
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Article Tc-99m Erythromycin Lactobionate Inhalation Scintigraphy in Parenchymal Lung Diseases(Elsevier Science inc, 1999) Durak, H; Aktogu, S; Degirmenci, B; Sayit, E; Ertay, T; Dereli, SWe have investigated Technetium 99m erythromycin lactobionate (Tc 99m EL) clearance from the lungs after inhalation, in the presence of an alveolitis. Eighteen patients (6 sarcoidosis, 7 idiopathic fibrosis, and 5 miliary tuberculosis) were imaged after the patients inhaled 1,110 MBq of Tc 99m EL. Clearance half time for the first 45 min, for 24 h, and retention at 24 h correlated with percentage of lymphocytes in bronchoalveolar lavage fluid (BAL) (r =.729, r =.883, and r =.826, respectively). There was a positive correlation between peripheral penetration (PP) and forced expiratory volume in 1 s (FEV1) (r =.806) and forced vital capacity (FVC) (r =.781). Retention was more marked in sarcoidosis compared with tuberculosis (0.025 < p less than or equal to 0.05). Radioaerosol lung imaging may reflect the pulmonary function impairment in parenchymal lung diseases. Retention of Tc 99m EL may be related to number of BAL cells or presence of a lymphocytic alveolitis. Long residency time of Tc 99m EL in the lungs implies that erythromycin can also be administered by inhalation for therapeutic purposes. NUCL MED BIOL 26;6:695-698, 1999. (C) 1999 Elsevier Science Inc. All rights reserved.Article Nanostructured Ox-MWCNT-Ppy-Au Electrochemical Sensor for Ultralow Detection of Retrorsine and Evaluation of Its Cytotoxic Effects on Liver Cells(Taylor & Francis Ltd, 2025) Akturk, Ezgi Zekiye; Njjar, Muath; Ata, Melek Tunc; Kaya, Ahmet; Akdogan, Abdullah; Onac, CananThis study presents the development of a novel retrorsine (RTS)-imprinted sensor utilizing oxidized multi-walled carbon nanotubes (Ox-MWCNTs), polypyrrole (PPy), and gold nanoparticles (AuNPs), employing square wave voltammetry for the sensitive and selective detection of RTS which causes oxidative-stress and DNA damage. The fabricated Ox-MWCNT-PPy-AuNP sensor demonstrated a surface-area of (0.218 cm2) is 4.25 times larger than a bare glassy carbon electrode, with a low charge transfer resistance (10.9 Omega), enhancing electron transfer kinetics. The sensor showed excellent sensitivity in detecting retrorsine, with a limit of detection of 0.035 nM in synthetic matrices and -0.030 nM in HepaRG cell culture medium. Toxicity assays in HepaRG cells revealed dose-dependent oxidative-stress, with glutathione levels decreasing from 23.08 +/- 0.21 mu mol/109 to 21.21 +/- 0.02 mu mol/109 at 35 mu M retrorsine. Concurrently, GSSG levels increased from 1.32 +/- 0.26 mu mol/109 to 2.22 +/- 0.02 mu mol/109. DNA-damage assessed via comet assay, showed significant increases in tail-moment (2.53 mu m) and tail-migration (16.13 mu m). Oxidative DNA-damage, indicated by 8-OHdG levels, increased significantly from 0.29 +/- 0.02 ng.mL- (control) to 0.47 +/- 0.07 ng.mL- at 35 mu M retrorsine. These findings demonstrate the sensor's effectiveness for retrorsine detection and its applicability in toxicological studies. The integration of nanomaterial engineering and molecular imprinting provides a highly sensitive, selective, and eco-friendly solution for monitoring toxic agents and assessing their biological impacts.Article Citation - WoS: 7Citation - Scopus: 9A Holistic Overview of the Applications of Grace-Observed Terrestrial Water Storage in Hydrology and Climate Science(Springer, 2025) Khorrami, Behnam; Gunduz, OrhanTerrestrial Water Storage (TWS) represents a vital element of the hydrological cycle, with its fluctuations significantly impacting the climate of the Earth and its ecological balance. Since its launch in 2002, the Gravity Recovery and Climate Experiment (GRACE) satellite mission has revolutionized the ability to observe and analyze large-scale mass changes within Earth's system components. This paper offers a comprehensive and current overview of GRACE satellite gravimetry, highlighting its relevance to hydrological and climate-related studies. It outlines the fundamental measurement principles of the GRACE mission, provides an in-depth explanation of GRACE data products (including spherical harmonic and mascon solutions), examines emerging trends in GRACE-based research, and reviews key applications in hydrology and climate science. Additionally, it addresses the major challenges in utilizing GRACE data and explores promising avenues for future research and applications.Article Citation - WoS: 1Citation - Scopus: 1Understanding the Role of a Specific Microenvironment in Personal Exposure To Semi-Volatile Organic Compounds Using Silicone Wristbands(Royal Soc Chemistry, 2025) Akmermer, Zulfikar; Demirtepe, HaleAssessment of personal exposure to semi-volatile organic compounds was facilitated using silicone wristbands (SWBs), an easy-to-use sampler that reflects total inhalation and dermal exposure from all the microenvironments and the activities in which the user was involved. Hence, SWBs help understand exposure from various routes, activities, and microenvironments. Offices are critical microenvironments where workers spend one-third of their daily time on weekdays; hence exposure from offices should be more extensively studied. This study aimed to investigate the personal exposure of university personnel and elaborate on the contribution of the exposure due to the office air to their overall exposure using SWBs. One SWB was worn by the participant, and another was hung in their office. After seven days of sampling on the wrist, exposure to polycyclic aromatic hydrocarbons (PAHs) was found to be related to combustion activities at home or from open fire, whereas exposure to organophosphate esters and phthalates was suggested to originate from building materials, such as flooring materials and paints, and consumer products, e.g. mattresses and furniture. PAHs in the participants' offices were influenced by the transport of outdoor air and phthalates from the ceiling material. Then, we estimated the equivalent air concentrations using the SWBs sampled from the offices and previously developed sampling rates and partition coefficients. The estimated office air exposure contributions to total inhalation and dermal exposure were 83%, 51%, and 39% for fluorene, tri(n-butyl) phosphate, and tris(2-chloro isopropyl) phosphate, respectively. These findings were consistent with the statistical analysis of personal data. To conclude, this study highlighted the importance of specific microenvironments in our exposure to particular SVOCs, offering strategies for indoor air quality management and human health risk assessment.Article Citation - WoS: 1Citation - Scopus: 1A Pragmatic Grouping Model for Bone-Only De Novo Metastatic Breast Cancer (MetS Protocol MF22-03)(MDPI, 2025) Goktepe, Berk; Demirors, Berkay; Senol, Kazim; Ozbas, Serdar; Sezgin, Efe; Lucci, Anthony; Soran, AtillaDe novo metastatic breast cancer (dnMBC) accounts for 3-10% of newly diagnosed cases, with 20-40% presenting as a bone-only metastatic disease, which can achieve survival outcomes exceeding 10 years with multimodal therapy. However, the role of multimodal therapy remains controversial in the guidelines. Objective: This study aims to identify dnBOMBC subgroups to develop a pragmatic staging system for guiding locoregional therapy decisions. Materials and Methods: Data from the MF07-01 phase III randomized trial (2021, median follow-up time (mFT): 40 months (range 1-131)) and the BOMET prospective multi-institutional registry trial (2021, mFT: 34 months (range 25-45)) were combined for analysis, including only patients who presented with bone-only metastases. Exclusion criteria were patients under 18 and those with a history of prior cancer or cancer metastases. Patients with missing data and positive surgical margins were excluded. Out of 770 patients, 589 were included. Survival analyses were first conducted according to molecular subgroups, after which patients were further stratified by hormone receptor status, human epidermal human epidermal growth factor receptor 2 (HER2) status, tumor grade, and clinical T (cT) stage. Group A (GrA) included hormone receptor (HR)-positive, low- or intermediate-grade tumors at any cT; HR-positive, high-grade tumors with cT0-3; or any HER2-positive tumors. Group B (GrB) included HR-positive, high-grade tumors with cT4 disease or any triple-negative (TN) tumors. Results: The hazard of death (HoD) was 43% lower in GrA than in GrB. Median OS was 65 months (39-104) for GrA patients and 44 months (28-72) for GrB patients (HR 0.57, 95% CI 0.41-0.78, p = 0.0003). Primary tumor surgery (PTS) significantly improved OS in GrA patients, regardless of the number of metastases (solitary: HR, 0.375, 95% CI 0.259-0.543, p < 0.001; multiple: HR 0.435, 95% CI 0.334-0.615, p < 0.001). Conversely, GrB patients did not experience a significant benefit from PTS. Conclusions: This study demonstrates that GrA patients have better OS than GrB patients, and PTS reduces the HoD in GrA patients compared to systemic therapy alone. These findings support using a modified staging system in dnBOBMC to identify patients who may benefit from multimodal therapy including PTS.Article Citation - WoS: 3Citation - Scopus: 3A Novel MIP Electrochemical Sensor Based on a CuFe2O4NPs@rGO Nanocomposite and Its Application in Breast Milk Samples for the Determination of Fipronil(Royal Soc Chemistry, 2025) Njjar, Muath; Akturk, Ezgi Zekiye; Kaya, Ahmet; Onac, Canan; Akdogan, AbdullahBackground: fipronil, a widely utilized insecticide in agriculture, has been shown to have potential health implications as it can accumulate in the environment and affect human health. Electrochemical sensors, specifically those incorporating molecularly imprinted polymers (MIPs), provide an efficient way for the detection of fipronil because of their selectivity and specificity. The combination of CuFe2O4NPs and reduced graphene oxide (rGO) exhibits a synergistic effect that enhances sensitivity and selectivity. The composite's effective properties provide a robust platform for fipronil determination in various matrices. This study detected fipronil using an electrochemical sensor based on a glassy carbon electrode (GCE) modified with MIP@CuFe2O4NPs@rGO. Results: the synthesized MIP@CuFe2O4NPs@rGO material was characterized using various techniques such as Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (FESEM), X-ray diffraction (XRD) analysis, energy dispersive X-ray (EDX) analysis, Brunauer-Emmett-Teller (BET) analysis, X-ray photoelectron spectroscopy (XPS) analysis, and electrochemical impedance spectroscopy (EIS). The modified GCE showed enhanced electrochemical behavior for fipronil, as demonstrated by cyclic voltammetry (CV) and square wave voltammetry (SWV) techniques. Optimization of parameters such as pH, pyrrole concentration, and template concentration further improved sensor performance. The sensor exhibited a linear dynamic range of 1 to 6 nM, with a limit of detection (LOD) of 0.30 nM (S/N = 3) and a limit of quantification (LOQ) of 1.08 nM (S/N = 10), highlighting its sensitivity and reliability. The precision of the method was excellent, with a relative standard deviation of less than 4.0%. When applied to quantify fipronil in breast milk samples, the sensor showed high accuracy and precision, with recoveries ranging from 96.24% to 97.75%. Significance: the sensor offers several advantages, including high sensitivity, specificity, and accuracy. Its ability to detect fipronil in complex matrices such as breast milk highlights its potential for real-world applications in environmental and health monitoring. Overall, this research paves the way for the development of efficient, rapid and eco-friendly sensors for detecting pesticide residues in various environmental and biological samples.Article Role of Long Non-Coding RNA X-Inactive Transcript (XIST) in Neuroinflammation and Myelination: Insights From Cerebral Organoids and Implications for Multiple Sclerosis(MDPI, 2025) Pepe, Nihan Aktas; Acar, Busra; Zararsiz, Gozde Erturk; Guner, Serife Ayaz; Sen, AlaattinBackground/Objectives: X-inactive-specific transcript (XIST) is a factor that plays a role in neuroinflammation. This study investigated the role of XIST in neuronal development, neuroinflammation, myelination, and therapeutic responses within cerebral organoids in the context of Multiple Sclerosis (MS) pathogenesis. Methods: Human cerebral organoids with oligodendrocytes were produced from XIST-silenced H9 cells, and the mature organoids were subsequently treated with either FTY720 or DMF. Gene expression related to inflammation and myelination was subsequently analyzed via qRT-PCR. Immunofluorescence staining was used to assess the expression of proteins related to inflammation, myelination, and neuronal differentiation. Alpha-synuclein protein levels were also checked via ELISA. Finally, transcriptome analysis was conducted on the organoid samples. Results: XIST-silenced organoids presented a 2-fold increase in the expression of neuronal stem cells, excitatory neurons, microglia, and mature oligodendrocyte markers. In addition, XIST silencing increased IL-10 mRNA expression by 2-fold and MBP and PLP1 expression by 2.3- and 0.6-fold, respectively. Although XIST silencing tripled IBA1 protein expression, it did not affect organoid MBP expression. FTY720, but not DMF, distinguished MBP and IBA1 expression in XIST-silenced organoids. Furthermore, XIST silencing reduced the concentration of alpha-synuclein from 300 to 100 pg/mL, confirming its anti-inflammatory role. Transcriptomic and gene enrichment analyses revealed that the differentially expressed genes are involved in neural development and immune processes, suggesting the role of XIST in neuroinflammation. The silencing of XIST modified the expression of genes associated with inflammation, myelination, and neuronal growth in cerebral organoids, indicating a potential involvement in the pathogenesis of MS. Conclusions: XIST may contribute to the MS pathogenesis as well as neuroinflammatory diseases such as and Alzheimer's and Parkinson's diseases and may be a promising therapeutic target.Article Biologically Informed Decision-Making for PMRT in PT3N0M0 Luminal Breast Cancers (Protocol MF22-02): International Multicenter Real-World Data(Cig Media Group, Lp, 2025) Soran, Atilla; Gultekin, Melis Bahadir; Venkatesulu, Bhanu Prasad; Barry, Parul Nafees; King, Caleb; Bhargava, Rohit; Vargo, John AustinTwo hundred and 2 women from 16 centers with pT3N0M0 hormone receptor (HR) positive, HER2 negative BC who underwent mastectomy were retrospectively analyzed. Patients were divided into 2 groups: PMRT (n = 130) and no PMRT (n = 69). Groups were compared in terms of overall survival (OS), loco-regional recurrence (LRR) rate, and distant metastases (DM) in light of Magee Equations Score (MS). At a median follow-up of 51.3 months for the no PMRT group and 65.9 months for the PMRT group (P =.041), 9% (n = 6) of patients from the no PMRT group and 2% (n = 3) from the PMRT group developed LRR (P = 0.047). There was no difference in local recurrence (1% in no PMRT group vs. 2% in PMRT group; P =.7) and distant recurrence (7% in no PMRT group vs. 3% in PMRT group; P =.16) in patients who received PMRT and no PMRT. Further comparison of the LRR in the no PMRT and PMRT groups in patients with an MS < 18 did not show a significant difference (3% vs. 4%; P =.64). However, among patients with an MS >= 18, no PMRT group had a higher LRR rate compared to the PMRT group (11% vs. 2%; P =.01). In patients with an MS >= 18, the administration of PMRT correlates with statistically significantly better LRR-free survival (HR 0.19; 95% CI 0.05-0.79; P =.02). Patients with MS <18 experience a comparable rate of recurrence irrespective of PMRT, while those with MS >= 18 have higher rates of LRR and thus should not omit PMRT. Background: Current guidelines do not list definitive recommendations for postmastectomy radiation therapy (PMRT) in patients with luminal pT3N0M0 breast cancer (BC). Increased data suggests de-escalation of radiation therapy (RT) in genomically defined biologically favorable luminal BCs. The goal of this study is to determine whether PMRT can be safely omitted for this specific subgroup of patients. Methods and materials: Two hundred and 2 women from 16 centers with pT3N0M0 hormone receptor (HR) positive, HER2 negative BC who underwent mastectomy were retrospectively analyzed. No patients received neoadjuvant chemotherapy. Three patients were excluded because of positive surgical margins. Patients were divided into 2 groups: PMRT (n = 130) and no PMRT (n = 69). Groups were compared in terms of overall survival (OS), loco-regional recurrence (LRR) rate, and distant metastases (DM) in light of the Magee Equations Score (MS), menopausal status/age, axillary surgery, pathology, lymphovascular invasion (LVI), adjuvant chemotherapy, and adjuvant endocrine therapy. Results: The majority of the patients had invasive ductal carcinoma (49%, n = 98). There was no significant difference regarding tumor size, axillary surgery, and adjuvant endocrine therapy between the 2 groups (P =.82, P =.28, P =.12, respectively). LVI was 19% (n = 39), and it was greater in the PMRT group (25% vs. 10%; P =.01). Patients in the PMRT group received more chemotherapy (66% vs. 30%; P <.001), had more grade 3 tumors (28% vs. 9%, P =.005), and were more premenopausal (49% vs. 22%; P =.0001). At a median follow-up of 51.3 months for the no PMRT group and 65.9 months for the PMRT group (P =.041), 9% (n = 6) of patients from the no PMRT group and 2% (n = 3) from the PMRT group developed LRR (P =.047). There was no difference in local recurrence (1% in no PMRT group vs. 2% in PMRT group; P =.7) and distant recurrence (7% in no PMRT group vs. 3% in PMRT group; P =.16) in patients who received PMRT and no PMRT. Further comparison of the LRR in the no PMRT and PMRT groups in patients with an MS < 18 did not show a significant difference (3% vs. 4%; P =.64). However, among patients with an MS >= 18, no PMRT group had a higher LRR rate compared to the PMRT group (11% vs. 2%; P =.01). In patients with an MS >= 18, the administration of PMRT correlates with statistically significantly better LRR-free survival (HR 0.19; 95% CI 0.05-0.79; P =.02). Conclusions: Our findings imply that when considering PMRT for patients with pT3N0M0, HR-positive, and HER2-negative BC, clinicians can benefit from a combination of pathological risk factors and recurrence prediction models. Patients with MS < 18 experience a comparable rate of recurrence irrespective of PMRT, while those with MS >= 18 have higher rates of LRR and thus should not omit PMRT. (c) 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.Article Citation - WoS: 1Citation - Scopus: 1Phase-Dependent Optical, Photocatalytic and Capacitive Properties of Tungsten Oxide Nanowires(Royal Soc Chemistry, 2025) Kahraman, Zeynep; Gungor, Ahmet; Buldu-Akturk, Merve; Tan, Metin; Alp, Emre; Erdem, Emre; Genc, AzizTransition metal oxides hold great promise across a wide range of applications due to favorable properties such as high abundance, low toxicity, and excellent stability. Nanoengineering approaches are essential for controlling the structural, optical, and electronic properties of these materials, enabling the achievement of desired characteristics in a cost-effective and environmentally friendly manner. In this study, we synthesize stoichiometric (WO3) and sub-stoichiometric (WO3-x) tungsten oxide nanowires by controlling their phases and morphologies through the hydrothermal method. This approach allows us to systematically investigate the effects of different phases and oxygen vacancies on the optical properties, as well as on photocatalytic and supercapacitance applications. We use the photodegradation of RhB as a benchmark for photocatalytic activity under various experimental conditions, revealing that oxygen vacancies significantly influence photocatalytic behavior. For example, WO3-x nanowires adsorb/degrade a substantial amount of RhB within short durations under ambient conditions, where WO3 nanowires are mostly inactive. The addition of H2O2 enhances the photocatalytic performance of WO3 nanowires over 30 minutes, with even better results under low pH conditions with H2O2. This study also explores the phase-dependent electrochemical properties of WO3 and WO3-x nanowires, providing insights into their potential for improved supercapacitor performance by leveraging their complementary properties in symmetric and asymmetric configurations. WO3-x, with a higher density of oxygen vacancies and thinner structure, offers enhanced conductivity and increased active sites for charge storage, resulting in superior specific capacitance and charge retention.Article Fluorescent Protein With Environmentally-Sensitive Fluorescence Lifetime for Quantitative Ph Measurement(Elsevier Science inc, 2025) Simonyan, Tatiana R.; Protasova, Elena A.; Mamontova, Anastasia, V; Shakhov, Aleksander M.; Bodunova, Daria, V; Sidorenko, Svetlana, V; Bogdanov, Alexey M.Intracellular pH is a key factor in cell homeostasis, regulated within specific compartments, and changes in pH can result from or affect biochemical pathways. This study explores a yellow fluorescent protein EYFP-G65T as a core for a time-resolved pH-indicator. Among the tested designs-a circular permutant, a chimeric SypHer3s-like construct, and an unmodified protein-the unmodified EYFP-G65T performed best for live-cell imaging. Upon two-photon excitation, purified EYFP-G65T exhibited a 4.5-fold increase in mean fluorescence lifetime across pH 5.5-7 and a 7-fold change in its major component's lifetime from pH 6.5-8. Using this indicator, we measured pH values ranging from 6 to 8 in various organelles, and mapped pH shifts in mitochondria and the Golgi apparatus in response to stimuli.