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Article Citation - Scopus: 5Real-World Data From Turkey: Is Sofosbuvir/Ledipasvir With or Without Ribavirin Treatment for Chronic Hepatitis C Really Effective?(AVES, 2021) Demirtürk,N.; Aygen,B.; Çelik,İ.; Mıstık,R.; Akhan,S.; Barut,Ş.; Doğan,N.; Karakeçili, Faruk; Asan, Ali; Özel, Selcan Arslan; Ersöz, Gülden; Yıldız, Orhan; Şimşek, Sümeyra; Tarakçı, HüseyinBackground: In this study, we aimed to investigate the efficacy and safety of sofosbuvir-based therapies in the treatment of chronic hepatitis C in real-world clinical practice. Methods: Data from patients with chronic hepatitis C treated with SOF/LDV ± RBV or SOF/RBV in 31 centers across Turkey between April 1, 2017, and August 31, 2018, were recorded in a nationwide database among infectious disease specialists. Demographics, clinical, and virological outcomes were analyzed. Results: A total of 552 patients were included in the study. The mean age of the patients was 51.28 ± 14.2, and 293 (55.8%) were female. The majority had HCV genotype 1b infection (65%), 75.04% of the patients underwent treatment, and non-cirrhosis was present at baseline in 381 patients (72.6%). SOF/LDV ± RBV treatment was given to 477 patients and 48 patients received SOF/RBV according to HCV genotype. The total SVR12 rate was 99% in all patients. Five patients experienced disease relapse during the study and all of them were genotype 2. In patients infected with HCV GT2, SVR12 was 77.3%. SVR was 100% in all patients infected with other HCV genotypes. All treatments were well tolerated by patients without causing severe adverse events. Side effects and side effects-associated treatment discontinuation rates were 28.2% and 0.4%, respectively. Weakness (13.7%) was the common side effect. Conclusion: The present real-world data of 525 patients with HCV genotypes 1, 1a, 1b, 3, 4, and 5 who underwent SOF/LDV ± RBV treatment in Turkey demonstrated a high efficacy and safety profile. HCV GT2 patients should be treated with more efficacious treatment. © Copyright 2021 by The Turkish Society of Gastroenterology • Available online at turkjgastroenterol.orgArticle Citation - WoS: 6Citation - Scopus: 6Revealing Defect Centers in Pbwo4 Single Crystals Using Thermally Stimulated Current Measurements(Aip Publishing, 2024) Isik, M.; Gasanly, N. M.The trap centers have a significant impact on the electronic properties of lead tungstate (PbWO4), suggesting their crucial role in optoelectronic applications. In the present study, we investigated and revealed the presence of shallow trap centers in PbWO4 crystals through the utilization of the thermally stimulated current (TSC) method. TSC experiments were performed in the 10-280 K range by applying a constant heating rate. The TSC spectrum showed the presence of a total of four peaks, two of which were overlapped. As a result of analyzing the TSC spectrum using the curve fit method, the activation energies of revealed centers were found as 0.03, 0.11, 0.16, and 0.35 eV. The trapping centers were associated with hole centers according to the comparison of TSC peak intensities recorded by illuminating the opposite polarity contacts. Our findings not only contribute to the fundamental understanding of the charge transport mechanisms in PbWO4 crystals but also hold great promise for enhancing their optoelectronic device performance. The identification and characterization of these shallow trap centers provide valuable insights for optimizing the design and fabrication of future optoelectronic devices based on PbWO4.Article Citation - WoS: 6Citation - Scopus: 8Evaluation of the Anatomical Measurements of the Temporomandibular Joint by Cone-Beam Computed Tomography(Via Medica, 2019) Ocak, M.; Sargon, M. F.; Orhan, K.; Bilecenoglu, B.; Geneci, F.; Uzuner, M. B.Background: To examine the detailed anatomy of the normal temporomandibular joint (TMJ) in a large series of patients divided into different age groups. Materials and methods: Cone-beam computed tomography images of 100 patients included in the study. Morphometric analysis regarding mandibular condyle and mandibular fossa, articular tubercle and the zygomatic arch was done. The volumetric and surface measurements of mandibular condyles (total tissue volume [TV], total bone volume [BV], bone surface area [BS] and percentage of bony tissue of the mandibular condyle [BV/TV] were also measured. Results: Statistical analysis was performed and statistically significant differences according to the side of the joint, sex, and age groups were reported. Additionally, correlations between aging and all of these parameters were also determined. Conclusions: TV, BV, BS and BV/TV parameters according to side, age, and sex groups were defined for normal TMJ which may help to understand the onset and progress of TMJ disorders.Article Citation - WoS: 15Citation - Scopus: 13K+-induced Conformational Changes in the Trimeric Betaine Transporter Betp Monitored by Atr-Ftir Spectroscopy(Elsevier Science Bv, 2013) Korkmaz, Filiz; Ressl, Susanne; Ziegler, Christine; Maentele, Werner; Mäntele, WernerThe trimeric Na+-coupled betaine symporter BetP from Corynebactrium glutamicum adjusts transport activity according to the external osmolality. BetP senses the increasing internal K+ concentration, which is an immediate consequence of osmotic upshift in C. glutamicum. It is assumed that BetP specifically binds potassium to yet unidentified binding sites, thereby inducing conformational changes resulting in activation. Atomic structures of BetP were obtained in the absence of potassium allowing only a speculative glimpse on a putative mechanism of K+-induced transport activation. The structural data suggest that activation in BetP is crucially linked to its trimeric state involving an interaction network between several arginines and glutamates and aspartates. Here, we describe the effect of K+-induced activation on the specific ionic interaction sites in terminal domains and loops and on the protomer-protomer interactions within the trimer studied by ATR-FTIR spectroscopy. We suggest that arginine and aspartate and/or glutamate residues at the trimeric interface rearrange upon K+-induced activation, although they remain assembled in an interaction network. Our data propose a two-step mechanism comprising first a change in solvent exposure of charged residues and second a modification of their interaction sites in a partner-switching manner. FTIR reveals a higher alpha-helical content than expected from the X-ray structures that we attribute to the structurally unresolved N-terminal domain modulating regulation. In situ H-1/H-2 exchange studies point toward an altered exposure of backbone regions to buffer solution upon activation, most likely due to conformational changes in both terminal domains, which further affects ionic interactions within the trimer. (C) 2013 Elsevier B.V. All rights reserved.Article Citation - WoS: 3Citation - Scopus: 5Investigation of the Effect of Hyperthyroidism on Endoplasmic Reticulum Stress and Transient Receptor Potential Canonical 1 Channel in the Kidney(Tubitak Scientific & Technological Research Council Turkey, 2021) Aykanat, Nuriye Ezgi Bektur; Şahin, Erhan; Kaçar, Sedat; Bağcı, Rıdvan; Karakaya, Şerife; Dönmez, Dilek Burukoğlu; Şahintürk, Varol; Bektur Aykanat, Nuriye Ezgi; Burukoğlu Dönmez, Dilek; Bektur, EzgiBackground/aim: Hyperthyroidism is associated with results in increased glomerular filtration rate as well as increased renin-angiotensin-aldosterone activation. The disturbance of Ca2+ homeostasis in the endoplasmic reticulum (ER) is associated with many diseases, including diabetic nephropathy and hyperthyroidism. Transient receptor potential canonical 1 (TRPC1) channel is the first cloned TRPC family protein. Although it is expressed in many places in the kidney, its function is uncertain. TRPC1 is involved in regulating Ca2+ homeostasis, and its upregulation increases ER Ca2+ level, activates the unfolded protein response, which leads to cellular damage in the kidney. This study investigated the role of TRPC1 in the kidneys of hyperthyroid rats in terms of ER stress markers that are glucose-regulated protein 78 (GRP78), activating transcription factor 6 (ATF6), (protein kinase R (PKR)-like endoplasmic reticulum kinase) (PERK), Inositol-requiring enzyme 1 (IRE1). Materials and methods: Twenty male rats were assigned into control and hyperthyroid groups (n = 10). Hyperthyroidism was induced by adding 12 mg/L thyroxine into the drinking water of rats for 4 weeks. The serum-free T3 and T4 (fT3, fT4), TSH, blood urea nitrogen (BUN), and creatinine levels were measured. The histochemical analysis of kidney sections for morphological changes and also immunohistochemical and western blot analysis of kidney sections were performed for GRP78, ATF6, PERK, IRE1, TRPC1 antibodies. Results: TSH, BUN, and creatinine levels decreased while fT3 and fT4 levels increased in the hyperthyroid rat. The morphologic analysis resulted in the capillary basal membrane thickening in glomeruli and also western blot, and immunohistochemical results showed an increase in TRPC1, GRP78, and ATF6 in the hyperthyroid rat (p < 0.05). Conclusion: In conclusion, in our study, we showed for the first time that the relationship between ER stress and TRPC1, and their increased expression caused renal damage in hyperthyroid rats.Key words: Hyperthyroidism, endoplasmic reticulum (ER) stress, transient receptor potential canonical 1 (TRPC1), kidney, ratArticle Citation - WoS: 11Citation - Scopus: 14Card Spending Dynamics in Turkey During the Covid-19 Pandemic(Central Bank Republic Turkey, 2021) Kantur, Zeynep; Özcan, GülserimThis paper provides an extensive analysis of card spending during the COVID-19 pandemic in Turkey by using weekly aggregated and sectoral credit and debit card spending data from March 2014 to December 2020. At an aggregated level, we show that aggregate demand decreases significantly at the early stages of COVID-19 and seems to reinstate its pre-COVID trend. However, when we include the pre-existing conditions of Turkey, the 2018 currency crisis, we observe that the recovery in demand is not that strong. To highlight the underlying reasons for structural change in aggregate demand, we estimate the model with stringency index and unemployment-related search index. The estimated model indicates that containment measures and restrictions and fear of job/income loss mainly explain the overall impact of COVID-19 on aggregate demand. We also examined sectoral data to understand aggregate demand dynamics better. Only stable and delayable sector groups have reached a trend above their pre-pandemic trajectories. However, the social and work-related sectors are far from their respective pre-pandemic trend.Article Citation - Scopus: 19Pulmonary rehabilitation principles in SARS-COV-2 infection (COVID-19): The revised guideline for the acute, subacute, and post-COVID-19 rehabilitation(Turkish Society of Physical Medicine and Rehabilitation, 2021) Aytür,Y.K.; Köseoglu,B.F.; Taşkıran,Ö.Ö.; Gökkaya,N.K.O.; Delialioğlu,S.Ü.; Tur,B.S.; Tıkız,C.Coronavirus disease 2019 (COVID-19) is a contagious infection disease, which may cause respiratory, physical, psychological, and generalized systemic dysfunction. The severity of disease ranges from an asymptomatic infection or mild illness to mild or severe pneumonia with respiratory failure and/or death. COVID-19 dramatically affects the pulmonary system. This clinical practice guideline includes pulmonary rehabilitation (PR) recommendations for adult COVID-19 patients and has been developed in the light of the guidelines on the diagnosis and treatment of COVID-19 provided by the World Health Organization and Republic of Turkey, Ministry of Health, recently published scientific literature, and PR recommendations for COVID-19 regarding basic principles of PR. This national guideline provides suggestions regarding the PR methods during the clinical stages of COVID-19 and post-COVID-19 with its possible benefits, contraindications, and disadvantages. © 2021 All right reserved by the Turkish Society of Physical Medicine and RehabilitationArticle STUDY ON CLOUD COMPUTING PERCEPTION OF TURKISH IT SECTOR(Univ Osijek, Tech Fac, 2016) Okan, Aylin Akca; Hacaloglu, Tuna; Yazici, AliIn this paper an empirical study was carried out to study the Cloud Computing (CC) perception in Turkey. To this extent this study intends to determine the perception of Information Technology decision makers such as Chief Executive Officers and Chief Information Officers by means of a survey by questionnaire approach to explore 98 both public and private IT executives' understandings and concerns about CC. The survey aims to determine how CC is perceived by public or private organizations that are already involved in the e-transformation process. Major results of the study are as follows: both public and private sector executives have positive perception over adoption of CC, participants think that especially web, e-mail, data storage and process management applications are adequate for CC. Lack of well-educated and experienced staff is found to be the common barrier on adopting CC by both public and private sector participants.Article Study on cloud computing perception of Turkish IT sector;(Strojarski Facultet, 2016) Akca Okan,A.; Hacaloglu,T.; Yazici,A.; Okan, Aylin AkcaIn this paper an empirical study was carried out to study the Cloud Computing (CC) perception in Turkey. To this extent this study intends to determine the perception of Information Technology decision makers such as Chief Executive Officers and Chief Information Officers by means of a survey by questionnaire approach to explore 98 both public and private IT executives’ understandings and concerns about CC. The survey aims to determine how CC is perceived by public or private organizations that are already involved in the e-transformation process. Major results of the study are as follows: both public and private sector executives have positive perception over adoption of CC, participants think that especially web, e-mail, data storage and process management applications are adequate for CC. Lack of well-educated and experienced staff is found to be the common barrier on adopting CC by both public and private sector participants. © 2016, Strojarski Facultet. All rights reserved.Article ISAR Imaging of Drone Swarms at 77 GHz(Tubitak Scientific & Technological Research Council Turkey, 2025) Coruk, Remziye Busra; Kara, Ali; Aydin, ElifThe proliferation of easily available, internet-purchased drones, coupled with the emergence of coordinated drone swarms, poses a significant security threat for airspace. Detecting these swarms is crucial to prevent potential accidents, criminal misuse, and airspace disruptions. This paper proposes a novel inverse synthetic aperture radar (ISAR) imaging technique for high-resolution reconstruction of drone swarms at 77 GHz millimeter wave (mmWave) frequency, offering a valuable tool for military and defense antidrone systems. The key parameters affecting down-range and cross-range resolution (0.05 m), ultimately enabling the generation of detailed ISAR images are discussed. Here, we create diverse scenarios encompassing various swarm formations, sizes, and payload configurations by employing ANSYS simulations. To enhance image quality, different window functions are evaluated, and the Hamming window is selected due to its highest peak signal-to-noise ratio (PSNR) (16.3645) and structural similarity (SSIM) (0.9067) values, ensuring superior noise reduction and structural preservation. The results demonstrate that the effectiveness of high-resolution ISAR imaging in accurately detecting and characterizing drone swarms pave the way for enhanced airspace security measures.
