İstanbul Medeniyet Üniversitesi Kurumsal Akademik Arşivi
DSpace@Medeniyet, İstanbul Medeniyet Üniversitesi tarafından doğrudan ve dolaylı olarak yayınlanan; kitap, makale, tez, bildiri, rapor, araştırma verisi gibi tüm akademik kaynakları uluslararası standartlarda dijital ortamda depolar, Üniversitenin akademik performansını izlemeye aracılık eder, kaynakları uzun süreli saklar ve üniversite adresli yayınların etkisini artırmak için telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Medial plating versus newly designed intramedullary nail with distal interlocking system for distal tibia fractures: A biomechanical study with finite element analysis
(Turkish Joint Diseases Foundation, 2026) Ünal, Ömer Kays; Dağtas, Mirza Zafer; Najafov, Turan; Demir, Cihan; Ugutmen, Ender; Akpinar, Fuat
Objectives
The aim of this study was to compare the biomechanical properties of a newly designed Tibial Intramedullary Nail-Distal Supportive Bolt Locking Screw (TIN-DSBLS) and medial anatomical plate in distal tibia fracture models using finite element analysis (FEA).
Materials and methods
Twelve medium-size, fourth-generation composite tibia models were used for testing. Models were divided into two groups as plate and nail group. A standardized osteotomy was made through each model. In the plate group, osteotomized models were fixed with distal tibia medial anatomic plate. Models in nail group were fixed with new design intramedullary nail with distal Bolt screw locking. All bone models were tested by an axial loading test machine to measure the force, maximum force, fracture site displacement and Stiffness. The second step of this study was FEA of the two models.
Results
The results of axial loading test results of two groups revealed that for distal tibia fracture, tibia nail which was locked with newly designed bolt screw showed superiority against plate-screw fixation about force (1597.76 ± 85.54 vs. 830.74 ± 146.7 N), maximum force (3617.6 vs. 1512.42 N), fracture site displacement (4.89 ± 1 vs. 7.85 ± 0.5 mm) and stiffness (357.88 ± 52.6 vs. 109.67 ± 13.6 N/mm). In FEA, maximum stress levels in implants were 1.7 time higher in nail group, bones were not exposed to higher levels of stress or deformation as in plate group. Maximum stress levels in bones of the nail group were 2.75 times lower than plate group. Total displacement in the plate group was more than two-fold compared to the nail group.
Conclusion
Our study results showed that the TIN-DSBLS provides more load transfer from the nail to the cortex in tibia distal metaphyseal fractures compared to traditional nails. Taken together, it is biomechanically superior to plate-screw fixation in fractures extending up to 2.5 cm proximal to the ankle joint.
Descriptive and Clinical Characteristics of Non-Survivors in a Tertiary Pediatric Intensive Care Unit in Turkey: 6 Years of Experience
(Necmettin Erbakan University NEU Press, 2025) Karakaya, Zeynep; Boyraz, Merve; Köksal Atış, Şeyma; Yüce, Servet; Duyu, Muhterem
Objectives: To identify the characteristics of non-survivors in a pediatric intensive care unit (PICU) in Turkey. Methods: This is a retrospective analysis of patients who died in a tertiary PICU over a 6year period from 2016 to 2021. Data were drawn from electronic medical records and resuscitation notes. Mode of death was categorized as failed cardiopulmonary resuscitation (F-CPR) or brain death (BD). Results: Among the 161 deaths, 136 non-survivors were included and 30.1% were younger than 1 year old. Severe pneumonia, respiratory failure and ARDS (31.6%) were the most common primary diagnoses. The most common mode of death was F-CPR (86.8%). More than half of the subjects had been admitted from pediatric emergency departments (58.1%), and more than half (53.7%) had died within 7 days in the PICU. Patients admitted from pediatric emergency departments had the lowest frequency of comorbidities (p<0.001). Severe pneumonia, respiratory failure and acute respiratory distress syndrome diagnoses were significantly more frequent in those who died after 7 days (p<0.001); whereas, septicemia, shock and multiple organ dysfunction were more common among those who died within the first day of PICU admission (p<0.001). Conclusions: It may be important to note that patients referred from wards are highly likely to have comorbidities, while those referred from pediatric emergency departments may be relatively younger. Additionally, patients with septicemia, shock or multiple organ dysfunction were more likely to die earlier (within 7 days), especially compared to those with severe pneumonia, respiratory failure or acute respiratory distress.
Necessary and Sufficient Tauberian Conditions for Logarithmic Summable Sequences in Two-Normed Spaces
(Soc Paranaense Matematica, 2025) Önder, Zerrin; Sezer, Sefa Anıl; Çanak, İbrahim
Our aim in this paper is to make a novel interpretation of the relation between the logarithmic summability method and convergence under the coverage of 2-normed spaces. In line with this aim, we introduce a necessary and sufficient Tauberian condition of Moricz-type for logarithmic summable sequences in these kinds of spaces. Following this, we investigate whether conditions designed as O-type such as the slow oscillation and Hardy-type conditions with respect to summability (& ell;, 1) due to the non-existence of relation of "order" in 2-normed spaces are the conditions needed for logarithmic summable sequences to be convergent.
Professional hysteresis: the changing asymmetries of the medical profession in Türkiye
(Edward Elgar Publishing, 2025) Koytak, Elyesa
This chapter aims to evaluate the sources of the complaining, protesting, and defensive attitude among Turkish physicians as a new type of professionalism. In the context of the rapid growth of the health-care system, how does the transformation of structures within the profession shape this new professionalism? This study draws from current conceptual debates on professionalism while advancing existing findings on the medical profession in Türkiye. The research, based on interviews with physicians working in public hospitals in Istanbul, reveals that professional grievances have four dimensions: the quantitative dimension of the current workload, the qualitative dimension of patient behaviour, new bureaucratic asymmetries, and new collegial asymmetries. The analysis mainly focuses on the temporal dimension of professionalism within these four asymmetries and aims to explain the increasing complaining and defensive attitude of physicians by using Bourdieu's concept of hysteresis. It explores how physician professionalism resorts to past schemes of perception amid rapid changes in the structural conditions of the field. When asymmetries such as limited access to health care, the closed and privileged status of the profession, bureaucratic lack of control, and collegial solidarity—foundations of the protected type of professionalism—are eroded and reversed, a situation I term “professional hysteresis” emerges, without necessarily leading to connective professionalism. © The Editor and Contributors Severally 2025. All rights reserved.
Diagnostic consistency of programmed death-ligand 1 immunohistochemistry – comparative analysis of SP142 and 22C3 clones in non-small cell lung cancer
(Vesalius University Medical Publishing, 2025) Şahin, Songül; Ayla, Şule
Programmed death-ligand 1 (PD-L1) expression is a critical predictive biomarker for immune checkpoint inhibitor therapies in non-small cell lung cancer (NSCLC). Although various antibody clones are used for immunohistochemical (IHC) detection, differences in platforms and scoring algorithms raise concerns regarding analytical agreement at clinically relevant thresholds. This study evaluated the analytical concordance between VENTANA SP142, VENTANA 22C3, and DAKO 22C3 PD-L1 IHC assays in NSCLC, focusing on therapeutic decision-making thresholds. Non-small cell lung cancer samples from 205 patients were stained using VENTANA SP142, VENTANA 22C3, and DAKO 22C3 assays. Programmed death-ligand 1 expression was assessed in tumor cells using predefined thresholds (< 1%, 1-49%, ≥ 50%). Inter-assay agreement was evaluated using intraclass correlation coefficients (ICC). Strong analytical agreement (ICC > 0.90) was observed between SP142 and both DAKO and VENTANA 22C3 assays in the < 1% and 1-49% expression groups. Agreement decreased between VENTANA SP142 and DAKO 22C3 at the ≥ 50% threshold (ICC = 0.704). Conversely, concordance between VENTANA and DAKO 22C3 was high across all thresholds, particularly in the < 1% and ≥ 50% subgroups (ICC = 1.0 and 0.867, respectively). VENTANA and DAKO 22C3 assays demonstrate high analytical agreement. While SP142 is comparable at low expression levels, its reliability declines at higher thresholds. These findings underscore the necessity of standardized assay selection for accurate immunotherapy stratification in NSCLC.
