AXSIS (Yeditepe Üniversitesi)
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Diagnostic utility of lipocalin 2 and metalloproteinase 9 levels in early-stage endometrial cancer
No full textBACKGROUND: Endometrial cancer (EC) is the fourth most common gynecologic malignancy among women. Histopathologic examination is considered gold-standard for diagnosis of EC. However, these examinations sometimes not be useful in distinguishing early stage types of EC. OBJECTIVES: The current study aimed to investigate the clinicopathological significance of Lipocalin-2 (LCN2), matrix metalloproteinase-9 (MMP9), and ferritin in tumor progression. METHODS: A total of 98 patients (55 women newly diagnosed with early-stage endometrial cancer [study group] and 43 women with benign endometrial pathologies [control group]) were enrolled. RESULTS: There was a significant difference between diagnosis (p < 0.001), surgical procedure (p < 0.001), pathology (p 0.002), stage (p < 0.001), lymphovascular invasion (LVI) (p 0.002), myometrial invasion (p < 0.001), and staining intensity (p < 0.001), MMP9 (p 0.023), LCN2 (p < 0.001), glucocorticoid (GC) (p 0.048), tumor necrosis factor-alpha (TNF-α) (p 0.044), menopause duration (p 0.001), body weight (p < 0.001), and body mass index (BMI) (p < 0.001) were found to be higher, and ferritin levels (p 0.047) were lower in the endometrial adenocarcinoma group compared to the benign endometrial pathologies. CONCLUSION: LCN2, MMP9, and ferritin are practical markers in early cases of endometrial cancer. Serum LCN2 and MMP9 levels may be good clinical tools for the auxiliary diagnosis of early-stage endometrial cancer. Ferritin was also significantly sensitive. Therefore, detecting these markers together may be more beneficial for cancer diagnosis.The Yeditepe University Open Access System is a compendium of indexed publications. Copyright and usage rights may be held by publishers and/or authors. The collection was established for the scientific publications prepared by Yeditepe University academicians and is to be found in the institutional archive.Methods: A total of 98 patients (55 women newly diagnosed with early-stage endometrial cancer [study group] and 43 women with benign endometrial pathologies [control group]) were enrolled
New Ibuprofen Cystamine Salts With Improved Solubility and Anti-Inflammatory Effect
No full textTwo novel ibuprofen cystamine salts (IBU-CYS 1 and IBU-CYS 2) are synthesized by coupling the anion of ibuprofen with cystamine dihydrochloride in 1 : 1 and 2 : 1 ratio to improve the solubility and bioavailability of ibuprofen. The salts are characterized by 1HNMR, FT-IR and UV-Vis spectroscopy, differential scanning calorimetry (DSC), thermogravimetry (TGA, DTA) and X-ray diffraction measurements. IBU-CYS 1 and IBU-CYS 2 show higher solubility (6.11 and 7.81 mg/mL) compared to ibuprofen (0.04 mg/mL) in water. IBU-CYS2 was encapsulated into 2-hydroxyethyl methacrylate: poly (ethylene glycol) acrylate hydrogels for enhanced delivery. The in vitro studies in PBS (pH 7.4) indicate that the salts are effective in relieving inflammatory responses induced by lipopolysaccharide in RAW264.7 macrophage cells (nitrite inhibition percentages of IBU-CYS 1, IBU-CYS 2 and ibuprofen: approximately 34.29, 27.03 and 31.50 respectively) while indicating no cytotoxicity. Therefore, these salts may be promising candidates for the development of effective formulations of this drug. © 2024 The Authors. ChemistryOpen published by Wiley-VCH GmbH.The Yeditepe University Open Access System is a compendium of indexed publications. Copyright and usage rights may be held by publishers and/or authors. The collection was established for the scientific publications prepared by Yeditepe University academicians and is to be found in the institutional archive
Academic Success in English Medium Courses: Exploring Student Challenges, Opinions, Language Proficiency and L2 Use
No full textThe growth of English medium instruction (EMI) programs at universities worldwide has raised questions about the implications of teaching through L2 English on students’ content learning outcomes. This study examined the impact of four factors on students’ academic success (e.g. content learning) in the Turkish EMI context: (1) students’ language-related challenges; (2) students’ opinions about the effectiveness of EMI; (3) students’ perceived language proficiency levels; and (4) the amount of L2 English used in EMI classes. Students’ perceived academic performance was taken as a proxy of EMI success. The study employed a quantitative empirical design using questionnaires and regression analysis. Data were collected via an online questionnaire from 498 students at an EMI university in Turkey. The results revealed that students’ language-related challenges and perceived language proficiency were the only predictors that were associated with academic success in their EMI courses at a statistically significant level. The amount of English used in the classroom was not found to predict success in EMI, suggesting that students may benefit from multilingual models of teaching. These findings underscore the importance of adequate language support for students on EMI programs, and implications are discussed with respect to EMI policy, program planning, and teacher pedagogy. © The Author(s) 2023.The Yeditepe University Open Access System is a compendium of indexed publications. Copyright and usage rights may be held by publishers and/or authors. The collection was established for the scientific publications prepared by Yeditepe University academicians and is to be found in the institutional archive
Virtual anatomical atlas of the deep brain nuclei
No full textThis study aims to improve understanding of the anatomy of the deep brain nuclei relevant to deep brain stimulation as well as stereotactic lesioning procedures, including radio frequency, high-focused ultrasound, and radiosurgery. We created interactive, three-dimensional virtual models from cadaveric dissections and radiological segmentation. We used five brain specimens (ten hemispheres) obtained from routine autopsies, prepared according to Klingler’s method. Dissections were done from lateral to medial, medial to lateral, and superior to inferior to expose deep brain stimulation targets and adjacent structures. Using photogrammetry, we scanned the specimens to create detailed three-dimensional models. These models were uploaded to an online platform for free global access. Radiological models were also generated from atlas-based regions using the Montreal Neurological Institute template. We produced 16 high-quality cadaveric models at various stages of dissection. These and the radiological models were examined and interacted with through augmented reality and virtual reality headsets. This approach allowed comprehensive visual access to the anatomical structures and delineated their spatial relationships. These three-dimensional models provide detailed anatomical representations that can enhance anatomical orientiation, improve spatial perception, and serve as valuable educational tools for clinicians and students. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.The Yeditepe University Open Access System is a compendium of indexed publications. Copyright and usage rights may be held by publishers and/or authors. The collection was established for the scientific publications prepared by Yeditepe University academicians and is to be found in the institutional archive
A three-stage matheuristic for home blood donation appointment reservation and collection routing
No full textIn Western countries, the so-called Blood Donation Supply Chain (BDSC) provides blood units to several health services. Its first echelon is the collection of unit from donors, which requires a careful management because an unbalanced supply of units to the rest of the chain could trigger alternating periods of blood shortage and wastage. However, the management of blood collection is only marginally studied in the literature, in comparison to other BDSC echelons. In this work, we propose a new organizational model for blood collection, in which blood is collected at donor’s homes, and provide a decision support tool for its management. This new model provides a novel contribution to the understudied blood collection echelon and, at the same time, it responds to the emerging need of delocalization of health services. The proposed decision support tool consists of an interconnected matheuristic framework with three decision stages: (i) a planning model to create the donation slots that will be assigned to donors, (ii) an online allocation of these slots using a flexible set of criteria, and (iii) a Multi-Trip Vehicle Routing Problem with Time Windows (MTVRP-TW) to route the bloodmobiles that collect blood at donors’ homes. The main goals are to balance the production of blood units between days and to minimize the distance travelled by the bloodmobile fleet, while respecting time windows negotiated with donors. This framework also has the feature of immediately providing a list of slots to choose from when a donor makes a booking request. The decision support tool has been tested on data from a real Italian provider. Results confirm its effectiveness, and the capability of providing good quality and economically sustainable solutions in reasonable timeframes. © The Author(s) 2023.The Yeditepe University Open Access System is a compendium of indexed publications. Copyright and usage rights may be held by publishers and/or authors. The collection was established for the scientific publications prepared by Yeditepe University academicians and is to be found in the institutional archive
A Computational Approach: Predicting iNOS Inhibition of Compounds for Alzheimer's Disease Treatment Through QSAR Modeling
No full textThis article presents the development of a quantitative structure-activity relationship (QSAR) model for predicting the inhibitory activity of inducible nitric oxide synthase (iNOS) by specific compounds used in Alzheimer's disease treatment. iNOS is a vital enzyme involved in nitric oxide (NO) production, contributing to neuroinflammation and neuronal damage in Alzheimer's disease. The QSAR model was developed using a dataset of 90 compounds with known iNOS inhibition activity. Molecular descriptors representing the compounds’ structural and physicochemical properties were calculated and employed as input variables. Five descriptors (MATS6p, Chi1_EA(dm), Mor17 s, NsssCH, and SHED_AL) were selected as optimal for developing the classification model. The Random Forest algorithm was chosen as the classifier, implemented using WEKA software. The model underwent rigorous internal and external validation to assess its performance. The resulting QSAR model exhibited outstanding predictive capabilities with an overall accuracy of 88.8 , a high correlation coefficient, and minimal prediction errors. It effectively forecasts iNOS inhibition activity of the chosen compounds, offering valuable insights for potential Alzheimer's disease treatments. This model significantly contributes to drug discovery, providing a rapid and cost-effective means of screening and prioritizing compounds with iNOS inhibitory potential. © 2024 Wiley-VCH GmbH.The Yeditepe University Open Access System is a compendium of indexed publications. Copyright and usage rights may be held by publishers and/or authors. The collection was established for the scientific publications prepared by Yeditepe University academicians and is to be found in the institutional archive
AI for industrial: automate the network design for 5G URLLC services
No full textFifth generation (5G) mobile networks enable ultra-reliable low-latency communication (URLLC) applications, ushering in an era of endless possibilities for 5G. URLLC supports emerging 5G services and applications with stringent requirements for latency and reliability. Factory automation (FA) is a URLLC application that automates and optimizes workflows and processes in factories. To accommodate diversified FA services, 5G networks employ the “network slicing” technique, which divides the network into slices tailored to different service requirements. Designing a sliced network and translating diversified service-level agreements (SLAs) into network attributes necessitates advanced automation techniques to enhance human–machine collaboration, increase efficiency, minimize manual errors, reduce operating costs, and, most importantly, provide adequate service quality economically and reliably. To apply autonomic computing to FA network design, new architectures and software components have been envisioned. These include information extraction, domain knowledge representation, rule-based reasoning, performance model calculation, and querying using simulators and neural networks (NNs), among others. This paper proposes an innovative approach to network slicing design using advanced automation methods. This approach can be easily extended to include new services or to integrate cutting-edge 5G techniques. © The Author(s) 2024.The Yeditepe University Open Access System is a compendium of indexed publications. Copyright and usage rights may be held by publishers and/or authors. The collection was established for the scientific publications prepared by Yeditepe University academicians and is to be found in the institutional archive
iNOS/PGE2 inhibitors as a novel template for analgesic/anti-inflammatory activity: Design, synthesis, in vitro biological activity and docking studies
No full textThe Yeditepe University Open Access System is a compendium of indexed publications. Copyright and usage rights may be held by publishers and/or authors. The collection was established for the scientific publications prepared by Yeditepe University academicians and is to be found in the institutional archive
Investigating Türkiye’s financial nexus: A wavelet coherence analysis of sovereign CDS spreads, bond yields, stock index, and FX rates
No full textThis article investigates the intricate relationships between sovereign credit default swaps (CDS) and various Turkish financial assets, including the US Dollar to Turkish Lira exchange rate (USDTRY), the Borsa Istanbul 100 (XU100) stock index, and government bond yields. Employing a rigorous wavelet coherence analysis that captures the timefrequency domain, this study utilizes daily data from November 2008 to July 2022 period containing important financial, economic and global health crises, such as Great Recession, European Debt Crises, and COVID-19 pandemic. The wavelet coherence results uncover that the causality between variables is contingent on both the frequency domain and evolves dynamically over time, with the most significant interdependencies manifesting in the medium term. Moreover, the analysis reveals that government bond yields, and their respective volatilities positively impact CDS spread and its volatility. Similarly, the USDTRY rate leads to positive changes in the CDS spread. By contrast, the volatility of CDS spreads positively influences foreign exchange volatility and the XU100 index volatility. The CDS spread negatively affects the XU100 index. Overall, the findings elucidate the direction of causality between Turkish CDS spread and retained Turkish financial assets and then provide valuable information on the predictive power of those securities for investors, financial risk managers, and policymakers. © 2024 by the authors.The Yeditepe University Open Access System is a compendium of indexed publications. Copyright and usage rights may be held by publishers and/or authors. The collection was established for the scientific publications prepared by Yeditepe University academicians and is to be found in the institutional archive
Is Quantitative Radiographic Measurement of Acetabular Version Reliable in Anteverted and Retroverted Hips?
No full textThe Yeditepe University Open Access System is a compendium of indexed publications. Copyright and usage rights may be held by publishers and/or authors. The collection was established for the scientific publications prepared by Yeditepe University academicians and is to be found in the institutional archive.Methods: We searched our image archives for patients who had received both radiographs and CT scans between January 2020 and June 2022 and found 84 patients who met the criteria. From these patients, we selected those who presented with hip pain of different causes and who had no previous elective and/or hip trauma surgery, no hip dysplasia, and results from adequate radiographic examinations. Accordingly, 73 (61 of 84) of the patients were included in this study, and angle measurements were performed on both hips of these patients (122 hips). Standardized positioning was meticulously verified for all plain radiographs and CT scans utilized in the measurement process. We measured quantitative angles and assessed qualitative signs of retroversion, including crossover, posterior wall, and ischial spine findings. We considered a hip with at least one of these findings a retroverted hip, and the hips without these findings were included in the anteverted hip group. Three clinicians took measurements independently. Measurement reliability and agreement were examined using intraobserver and interobserver intraclass correlation coefficients (ICCs), with statistical analyses including paired and independent t-tests. To investigate the reliability of quantitative radiographic and CT methods, we assessed both intraobserver and interobserver agreements. To explore the reliability disparities in measuring the acetabular version via radiography and CT in anteverted and retroverted hips, we analyzed the agreement between measurements from both modalities in the hip groups. Furthermore, to evaluate the degree of variation in acetabular version measurements when comparing quantitative radiographic and CT methods in anteverted and retroverted hips, we utilized paired and independent t-tests to examine the measurement differences within these hip categories. The difference between radiographic and CT measurements was also evaluated by Bland-Altman analysis.Background: The acetabular version is crucial for hip function, and its accurate assessment is necessary for treating patients with hip disorders. Current studies reveal discrepancies in the precision of quantitative radiographic measurements versus CT measurements, but there is a lack of focused analysis on anteverted versus retroverted hips. This study aims to fill this gap by directly comparing the reliability of these two methods in assessing varied hip configurations. Questions/purposes (1) How reliable are quantitative radiographic and CT methods in measuring the acetabular version angle? (2) Is there any difference in the reliability of acetabular version angle measurements using radiography compared with CT in anteverted and retroverted hips? (3) What is the extent of variation in acetabular version measurements when quantitative radiographic and CT methods are compared in anteverted and retroverted hips? Methods We searched our image archives for patients who had received both radiographs and CT scans between January 2020 and June 2022 and found 84 patients who met the criteria. From these patients, we selected those who presented with hip pain of different causes and who had no previous elective and/or hip trauma surgery, no hip dysplasia, and results from adequate radiographic examinations. Accordingly, 73 (61 of 84) of the patients were included in this study, and angle measurements were performed on both hips of these patients (122 hips). Standardized positioning was meticulously verified for all plain radiographs and CT scans utilized in the measurement process. We measured quantitative angles and assessed qualitative signs of retroversion, including crossover, posterior wall, and ischial spine findings. We considered a hip with at least one of these findings a retroverted hip, and the hips without these findings were included in the anteverted hip group. Three clinicians took measurements independently. Measurement reliability and agreement were examined using intraobserver and interobserver intraclass correlation coefficients (ICCs), with statistical analyses including paired and independent t-tests. To investigate the reliability of quantitative radiographic and CT methods, we assessed both intraobserver and interobserver agreements. To explore the reliability disparities in measuring the acetabular version via radiography and CT in anteverted and retroverted hips, we analyzed the agreement between measurements from both modalities in the hip groups. Furthermore, to evaluate the degree of variation in acetabular version measurements when comparing quantitative radiographic and CT methods in anteverted and retroverted hips, we utilized paired and independent t-tests to examine the measurement differences within these hip categories. The difference between radiographic and CT measurements was also evaluated by Bland-Altman analysis. Results Quantitative radiographic measurements showed intraobserver and interobserver reliabilities with ICCs of 0.87 (95 CI 0.84 to 0.91) and 0.78 (95 CI 0.75 to 0.82), respectively, and CT measurements demonstrated higher reliabilities with ICCs of 0.92 (95 CI 0.90 to 0.93) and 0.91 (95 CI 0.89 to 0.92), respectively. The reliability of measuring the acetabular version in anteverted hips was moderate, with an ICC of 0.59 (95 CI 0.49 to 0.68). In contrast, retroverted hips showed an ICC of -0.41 (95 CI -1.17 to 0.08), indicating a lack of consistency between quantitative radiographic and CT measurements. Variation in measurement on plain radiographs in anteverted hips was less than that of retroverted hips (mean 6 SD absolute difference between anteverted hips and retroverted hips 3° 6 3° versus 6° 6 4°; p 0.0001), indicating greater variability in the radiographic measurement of retroverted hips. According to Bland-Altman analysis, we observed that the difference between radiographic and CT measurements was well outside the CI, especially in retroverted hips. Conclusion Although quantitative radiographic measurement demonstrates acceptable intraobserver and interobserver reliabilities, its precision is lower than that of CT-based measurements. Specifically, quantitative radiographic methods are prone to a larger margin of error in retroverted hips. For more precise assessments of acetabular version, especially in retroverted hips, we recommend using CT measurement instead of the radiographic method. Copyright © 2024 The Author(s)