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Article Citation - WoS: 2Citation - Scopus: 2Potential Role of SGLT-2 Inhibitors in Improving Allograft Function and Reducing Rejection in Kidney Transplantation(Wiley, 2025) Demir, Mehmet Emin; Helvaci, Ozant; Yildirim, Tolga; Merhametsiz, Ozgur; Sezer, SirenSodium-glucose cotransporter-2 inhibitors (SGLT-2i) have demonstrated renoprotective and cardioprotective benefits beyond their antiglycemic effects. Their potential utility in kidney transplant recipients (KTRs) for preserving graft function and reducing rejection risk is currently under active investigation. Preliminary studies indicate that SGLT-2i therapy stabilizes estimated glomerular filtration rate (eGFR), decreases glomerular hyperfiltration, and improves metabolic outcomes in KTRs. Emerging clinical evidence also suggests that SGLT-2i may be associated with reduced rates of acute rejection, although direct immunosuppressive actions remain unclear. Experimental findings further suggest that SGLT-2i modulates gene regulation pathways involved in inflammation, oxidative stress, and fibrosis, contributing to improved allograft outcomes. Current safety data in KTRs are reassuring, without significant increases in urinary tract infections or adverse graft events. Nevertheless, long-term prospective studies specific to transplant populations are lacking. This review summarizes available evidence regarding the mechanisms of action, clinical efficacy, and safety profile of SGLT-2i in kidney transplantation, emphasizing their metabolic, hemodynamic, inflammatory, and immunomodulatory effects.Article Citation - WoS: 2Citation - Scopus: 2Investigations of Ph-Dependent Dynamic Properties of Ompg-16sl, an Outer Membrane Protein G Mutant by Atr-Ftir Spectroscopy(Elsevier, 2022) Yilmaz, Irem; Korkmaz, FilizIn this paper, the dynamic properties of outer membrane protein G mutant (OmpG-16SL) are investigated with ATR-FTIR spectroscopy. While OmpG-WT has 14 beta-strands in its structure, the mutant is designed to have 16 beta-strands with the intention of creating an enlarged pore. Loop L6 is elongated by introducing six residues, two of which are negatively charged. The solvent accessibility of the OmpG-16SL mutant is compared with WT and a previously reported mutant OmpG-16S by tracking the H-1/H-2 exchange kinetics in acidic and neutral buffer conditions. The exchange kinetics and dynamics in the fast and slow exchange phases are separately investigated using the 2DCOS technique, which enables the tracking of the structural changes at each phase of the exchange process. The results suggest that the mutant OmpG-16SL is equally exposed to buffer in both acidic and neutral pH conditions. Additionally, the time range in the fast phase is very short - one-tenth of that for WT - and most of the exchange is completed in this phase. This fast exchange within minutes is also indicative of the presence of highly flexible and/or unstructured regions. In all, the fast exchange rates independent of the buffer pH justify the assumption that there is an altered interaction among the charged residues, which leads to a steadily-open pore. The role of the side-chain interactions within the pore and between the loops involving the loop L6 is also discussed.Article Citation - WoS: 19Citation - Scopus: 18Deviations From Born-Oppenheimer Theory in Structural Chemistry: Jahn-Teller, Pseudo Jahn-Teller, and Hidden Pseudo Jahn-Teller Effects in C3h3< and C3h3<(Amer Chemical Soc, 2013) Kayi, H.; Garcia-Fernandez, P.; Bersuker, I. B.; Boggs, J. E.The electronic structure and vibronic coupling in two similar molecular systems, radical C3H3 and anion C3H3-, in ground and excited states, are investigated in detail to show how their equilibrium structures, in deviation from the Born-Oppenheimer approximation, originate from the vibronic mixing of at least two electronic states, producing the Jahn-Teller UT), pseudo JT (PJT), and hidden PJT effects. Starting with the high-symmetry geometry D3h of C3H3, we evaluated its 2-fold degenerate ground electronic state 2E" and two lowest excited states 2A,' and 2E' and found that all of them contribute to the distortion of the ground state via the JT vibronic coupling problem E" e' and two PJT problems (E" + A(1)') circle star e" and (E" + E') circle times (a2" + e"); all the three active normal modes e'(1335 e"(1030 cm(-1)), and a2"(778 cm(-1)) are imaginary, meaning that all the three vibronic couplings are sufficiently strong to cause instability, albeit in different directions. The first of them, the ground state JT effect, enhances one of the C-C bonds (toward an ethylenic form with C-2v symmetry), while the two PJT effects produce, respectively, cis (a(2)" toward C-3v symmetry) and trans (e") puckering of the hydrogen atoms. As a result, C3H3 has two coexisting equilibrium configurations with different geometry. In the C3H3- anion, the ground electronic state in DA symmetry is an orbitally nondegenerate spin triplet (3)A(2)' with a group of close in energy singlet and triplet excited states in the order of (1)A(1),', (3)A(1)', E-1", E-3", and E-1'. This shows that two PJT couplings, (3A(2)' + (3)A(1)") circle times a(2)" and (3A2' + 3E") e", may influence the geometry of the equilibrium structure in the 3A2' state. Indeed, both vibrational modes, a(2)"(1034 cm(-1)) and e"(1284 cm(-1)), are imaginary in this state. Similar to the radical case, they produce, respectively, cis (a(2)") and trans (e") puckering of the hydrogen atoms, but no e' distortion of the basic C-3 triangle; the equilibrium configuration with Cs symmetry occurs along the stronger e" distortions. Another higher-in-energy triplet-state minimum with C-2v symmetry emerges as a result of a strong JTE in the excited 3E" electronic state. In addition to these APES minima with spin-triplet electronic states, the system has a coexisting minimum with a spin-singlet electronic state, which is shown to be due to the hidden PJT effect that couples two singlet excited states. The two lowest equilibrium configurations of the C3H3- anion with different geometry and spin realize a (common to all electronic e(2) configurations) magnetic and structural bistability accompanied by a spin crossover. Some general spectroscopic consequences are also noted. As a whole, this article is intended to demonstrate the efficiency of the vibronic coupling approach in rationalizing the origin of complicated structural features of molecular systems as due to a combination of nonadiabatic JT effects.Article Citation - WoS: 5Citation - Scopus: 7Deadline-Aware Energy-Efficient Query Scheduling in Wireless Sensor Networks With Mobile Sink(Hindawi Ltd, 2013) Karakaya, MuratMobile sinks are proposed to save sensor energy spent for multihop communication in transferring data to a base station (sink) in Wireless Sensor Networks. Due to relative low speed of mobile sinks, these approaches are mostly suitable for delay-tolerant applications. In this paper, we study the design of a query scheduling algorithmfor query-based data gathering applications using mobile sinks. However, these kinds of applications are sensitive to delays due to specified query deadlines. Thus, the proposed scheduling algorithm aims to minimize the number of missed deadlines while keeping the level of energy consumption at the minimum.Article Citation - WoS: 8Citation - Scopus: 10Biomechanical Effects of Two Different Collar Implant Structures on Stress Distribution Under Cantilever Fixed Partial Dentures(Taylor & Francis Ltd, 2011) Meric, Gokce; Erkmen, Erkan; Kurt, Ahmet; Eser, Atilim; Ozden, Ahmet UtkuObjective. The purpose of the study was to compare the effects of two distinct collar geometries of implants on stress distribution in the bone around the implants supporting cantilever fixed partial dentures (CFPDs) as well as in the implant-abutment complex and superstructures. Materials and methods. The three-dimensional finite element method was selected to evaluate the stress distribution. CFPDs which was supported by microthread collar structured (MCS) and non-microthread collar structured (NMCS) implants was modeled; 300 N vertical, 150 N oblique and 60 N horizontal forces were applied to the models separately. The stress values in the bone, implant-abutment complex and superstructures were calculated. Results. In the MCS model, higher stresses were located in the cortical bone and implant-abutment complex in the case of vertical load while decreased stresses in cortical bone and implant-abutment complex were noted within horizontal and oblique loading. In the case of vertical load, decreased stresses have been noted in cancellous bone and framework. Upon horizontal and oblique loading, a MCS model had higher stress in cancellous bone and framework than the NMCS model. Higher von Mises stresses have been noted in veneering material for NMCS models. Conclusion. It has been concluded that stress distribution in implant-supported CFPDs correlated with the macro design of the implant collar and the direction of applied force.Article Citation - WoS: 1Citation - Scopus: 1Cold War Aviation: American Technology Transfer and the Construction of Turkey's First International Civilian Airport in Yeşilköy, Istanbul, 1944-1953(Cambridge Univ Press, 2024) Tunc, Tanfer Emin; Tunc, GokhanWith the economic and political support of the United States, in July 1947, Turkey signed contracts withthe Westinghouse Electric International Company and J.G. White Engineering Corporation to constructits first international civilian airport, Istanbul'sYe & scedil;ilk & ouml;y Airport. As this article will argue, the buildingof Ye & scedil;ilk & ouml;y (1949-53), through a partnership with two American engineering firms, is essentially anearly Cold War narrative of transnational exchange involving the multidirectional flow of technicalknowledge, expertise and resources between the United States and Turkey; the circulation of geopol-itically significant (and frequently competing) military, civilian and government actors; and thelocal and global implications of these transmissions. Yet the Ye & scedil;ilk & ouml;y construction narrative also illus-trates how post-war technology transfer was a highly political process of constant adaptation, modifi-cation and negotiation. Fraught with unforeseen friction and thorny challenges, Ye & scedil;ilk & ouml;y exemplifiesthe complicated American Cold War strategy of creating and maintaining alliances through engineeringknowledge, personnel and practices, often with unintended consequences. Moreover, as a case study,Ye & scedil;ilk & ouml;y opens a new window into the cautious science diplomacy that occurred along the IronCurtain, while filling a notable historiographic gap with respect to aviation in early Cold War Turkey.Article Citation - WoS: 2Citation - Scopus: 2Biosorption of Reactive Dyes by Novel Bacterium Leclercia Adecarboxylata: Complete Removal of Reactive Black 5 and Molecular Insights Into the Adsorption Mechanism(Wiley, 2025) Sen, Seda; Korkmaz, Filiz; Kilic, Nur KocberberLeclercia adecarboxylata isolated from the D & uuml;den Waterfall (Turkey) was utilized as a biosorbent for the removal of Reactive Black 5 (RB5), Setazol Blue BRF-X (BRF-X), Setazol Navy Blue SBG (SNB), and Setazol Turquoise Blue G (STBG). Of the dyes, RB5 was removed with the highest efficiency, 97.4% after 60 min. The effect of parameters such as pH (3-9), initial biosorbent dose (0.1-2.0 g/L), and initial dye concentration (25-1200 mg/L) on the biosorption of RB5 was investigated. Increasing the biosorbent dosage from 0.1 to 2.0 g/L enhanced the RB5 removal from 55.3% to 100% within 10 min. The complete removal (100%) of RB5 was achieved in media with 2.0 g/L biosorbent and 25 mg/L RB5 at pH 3 after 10 min. Additionally, the soluble extracellular polymeric substances (EPS) of L. adecarboxylata were found to consist of proteins, lipids, nucleic acids, and polysaccharides according to Fourier transform infrared spectroscopy (FTIR) analysis. The EPS was found to play a crucial role in dye removal, forming chemical interactions with dye molecules. Zeta potential analysis was used to evaluate the charge distribution on the biosorbent surface (-12.6 +/- 1.1 mV) and its interactions in the biosorption process. Kinetic and isotherm models suggested a complex interaction mechanism between the biomass and the dye. Adsorption isotherm data were analyzed via nine isotherm models. Among them, the Hill model was found to be the best fit for describing the equilibrium adsorption process of the RB5 (R2 = 0.9993). Overall, the applied models elucidated the influence of both physical and chemical interactions on the mechanism. Kinetic studies revealed that the adsorption of RB5 fit a pseudo-second-order kinetic model. The unique biochemical composition of the indigenous L. adecarboxylata biosorbent provided a high affinity for RB5, offering a sustainable, rapid, and economical solution for the treatment of dye-polluted water.Article Citation - WoS: 3Citation - Scopus: 3Expectancy From, and Acceptance of Augmented Reality in Dental Education Programs: a Structural Equation Model(Wiley, 2024) Toker, Sacip; Akay, Canan; Basmaci, Fulya; Kilicarslan, Mehmet Ali; Mumcu, Emre; Cagiltay, Nergiz ErcilObjectiveDental schools need hands-on training and feedback. Augmented reality (AR) and virtual reality (VR) technologies enable remote work and training. Education programs only partially integrated these technologies. For better technology integration, infrastructure readiness, prior-knowledge readiness, expectations, and learner attitudes toward AR and VR technologies must be understood together. Thus, this study creates a structural equation model to understand how these factors affect dental students' technology use.MethodsA correlational survey was done. Four questionnaires were sent to 755 dental students from three schools. These participants were convenience-sampled. Surveys were developed using validity tests like explanatory and confirmatory factor analyses, Cronbach's alpha, and composite reliability. Ten primary research hypotheses are tested with path analysis.ResultsA total of 81.22% responded to the survey (755 out of 930). Positive AR attitude, expectancy, and acceptance were endogenous variables. Positive attitudes toward AR were significantly influenced by two exogenous variables: infrastructure readiness (B = 0.359, beta = 0.386, L = 0.305, U = 0.457, p = 0.002) and prior-knowledge readiness (B = -0.056, beta = 0.306, L = 0.305, U = 0.457, p = 0.002). Expectancy from AR was affected by infrastructure, prior knowledge, and positive and negative AR attitudes. Infrastructure, prior-knowledge readiness, and positive attitude toward AR had positive effects on expectancy from AR (B = 0.201, beta = 0.204, L = 0.140, U = 0.267, p = 0.002). Negative attitude had a negative impact (B = -0.056, beta = -0.054, L = 0.091, U = 0.182, p = 0.002). Another exogenous variable was AR acceptance, which was affected by infrastructure, prior-knowledge preparation, positive attitudes, and expectancy. Significant differences were found in infrastructure, prior-knowledge readiness, positive attitude toward AR, and expectancy from AR (B = 0.041, beta = 0.046, L = 0.026, U = 0.086, p = 0.054).ConclusionInfrastructure and prior-knowledge readiness for AR significantly affect positive AR attitudes. Together, these three criteria boost AR's potential. Infrastructure readiness, prior-knowledge readiness, positive attitudes toward AR, and AR expectations all increase AR adoption. The study provides insights that can help instructional system designers, developers, dental education institutions, and program developers better integrate these technologies into dental education programs. Integration can improve dental students' hands-on experience and program performance by providing training options anywhere and anytime.Article Citation - WoS: 76Citation - Scopus: 80Unique Ligand-Based Oxidative Dna Cleavage by Zinc(ii) Complexes of Hpyramol and Hpyrimol(Wiley-v C H verlag Gmbh, 2007) Maheswari, Palanisamy Uma; Barends, Sharief; Oezalp-Yaman, Seniz; de Hoog, Paul; Casellas, Helene; Teat, Simon J.; Reedijk, Jan; Özalp-Yaman, SenizThe zinc(II) complexes reported here have been synthesised from the ligand 4-methyl-2-N-(2-pyridylmethyl)aminophenol (Hpyramol) with chloride or acetate counterions. All the five complexes have been structurally characterised, and the crystal structures reveal that the ligand Hpyramol gradually undergoes an oxidative dehydrogenation to form the ligand 4-methyl-2-N-(2-pyridylmethylene)aminophenol (Hpyrimol), upon coordination to Zn-II. All the five complexes cleave the phi X174 phage DNA oxidatively and the complexes with fully dehydrogenated pyrimol ligands were found to be more efficient than the complexes with non-dehydrogenated Hpyramol ligands. The DNA cleavage is suggested to be ligand-based, whereas the pure ligands alone do not cleave DNA. The DNA cleavage is strongly suggested to be oxidative, possibly due to the involvement of a non-diffusible phenoxyl radical mechanism. ne enzymatic religation experiments and DNA cleavage in the presence of different radical scavengers further support the oxidative DNA cleavage by the zinc(II) complexes.Article Investigation of Human Herpesvirus 8 & Leishmania Species in Malignant Skin Tumours, Psoriasis, Actinic Keratoses, & Seborrheic Keratoses: a Single-Center Experience From Ankara, Turkey(Scientific Scholar Llc, 2025) Bakir, Ayfer; Usluca, Selma; Kartal, Selda Pelin; Alper, MuratBackground & objectives: The role of human herpesvirus-8 (HHV-8) and Leishmania species in the aetiology of malignant skin tumours and proliferative skin diseases remains a topic of debate. This study aims to analyse formalin-fixed, paraffin-embedded (FFPE) skin biopsy samples using polymerase chain reaction (PCR) to determine whether skin lesions caused by HHV-8 and Leishmania spp. resemble malignant and proliferative skin diseases and assess the role of these pathogens in disease aetiology. Methods: In this retrospective, single-center observational study, skin biopsies were collected from 275 individuals diagnosed with malignant skin tumours, psoriasis, actinic keratoses, seborrheic keratoses, and chronic dermatitis. The presence of HHV-8 and Leishmania spp. in biopsy samples was evaluated Results: HHV-8 DNA was not detected in any of the samples using PCR. However, Leishmania spp. DNA was identified in 8.4 per cent of all samples (n=23). No positivity was observed in the control group (P=0.387). Leishmania spp. DNA PCR positivity was most frequently detected in psoriasis cases (32.4%), followed by actinic keratosis (AK) (8.7%), malignant skin tumours (4.2%), and seborrheic keratosis (SK) (3.8%). When the Leishmania positivity rate in individuals diagnosed with psoriasis was compared with that of the control group, the difference was found to be significant (P=0.002). The positivity rate in squamous cell carcinoma (SCC) (7.3%) was higher than in basal cell carcinoma (1.6%). Interpretation & conclusions: The findings in this study suggests that there is no relationship between malignant and proliferative skin diseases and HHV-8. However, Leishmania spp. DNA was detected in 8.4 per cent of all samples. Biopsy-archived samples may be preferred for the differential diagnosis of Leishmania in diseases that do not respond to treatment and in atypical clinical presentations.
