Publications by authors named "Seren M"

The present work focuses on the dynamics of the ionic constituents of 1-propyl-3-methyl-imidazolium-bis-(trifluormethylsulfonyl)-imide (PT), a paradigmatic ionic liquid, as an additive in poly(vinylpyrrolidone) (PVP). Hence, the resulting product can be regarded as a polymer electrolyte as well as an amorphous dispersion. Leveraging dielectric spectroscopy and oscillatory shear rheology, complemented by differential scanning calorimetry, the spectral shapes and the relaxation maps of the supercooled PVP-PT mixtures are accessed in their full compositional range.

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Finite-element modelling has been used to simulate local strains and stresses within free-standing polycrystalline slabs of W, Cu and W-Cu, heated with free or constrained boundaries. The elastic strain values in crystallites that satisfied the diffraction condition were used to simulate the lattice strain data that would be obtained from diffraction analysis, from which the average stresses within diffracting domains were computed. Comparison of direct-space stresses in the model with the average stresses determined from diffraction analysis shows that the representative volume elements (RVEs) required to obtain equivalent stress/strain values depend on the deformation mode suffered by the material.

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Background: In this study, we present the short-term results of revascularization of left subclavian artery with the chimney technique in patients with aortic dissection or transection who underwent Zone 2 thoracic endovascular aortic repair.

Methods: A total of 11 patients (6 males, 5 females; mean age: 56.4±11.

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Background: In this study, we aimed to present our mid-term results of basilic vein transposition in the forearm to create an arteriovenous fistula.

Methods: Between January 2015 and October 2017, a total of 21 patients (13 males, 8 females; mean age 54.2±11.

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Objective: Diabetes mellitus is recognized as a risk factor for mortality and morbidity after coronary bypass grafting. We aimed to determine the association between preoperative hemoglobin HbA1c and AF after isolated off-pump coronary bypass grafting (OPCAB).

Methods: The seventy-two diabetic patients undergoing isolated off-pump coronary bypass grafting were retrospectively analyzed for AF.

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Objective Patients with healed venous ulcers often experience recurrence of ulceration, despite the use of long-term compression therapy. This study examines the effect of closing incompetent perforating veins (IPVs) on ulcer recurrence rates in patients with progressive lipodermatosclerosis and impending ulceration. Methods Patients with nonhealing venous ulcers of >2 months' duration underwent duplex ultrasound to assess their lower extremity venous system for incompetence of superficial, perforating, and deep veins.

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Objective: The aim of this study was to explore the clinical effects of intralesional administration of an epidermal growth factor (EGF) up to complete wound closure.

Methods: Seventeen diabetic patients with full-thickness lower extremity ulcers of more than 4 weeks of evolution were enrolled in the study. Mean ulcer size was 15.

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Aim: In this study, we sought to determine the early postoperative results of arterio-venous fistulae (AVF) created by U-vein compressors with veins between 1.5 and 2 mm in size.

Methods: Pre-operative venous mapping was done.

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Objective: To examine the efficacy and durability of an interwoven self-expanding nitinol stent for the treatment of superficial femoral and popliteal arteries.

Method: Consecutive patients with severely diseased superficial femoral and popliteal arteries who received SUPERA® stents were retrospectively identified.The patients were followed for 12 months by Doppler ultrasound examinations, stent roentgenograms, and estimation of Rutherford-Becker class and ankle-brachial index.

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Background: Pulmonary embolism (PE) associated with hemodynamic instability has exceedingly high mortality. We describe our experience using percutaneous mechanical thrombectomy (PMT) in patients with massive PE (MPE) and submassive PE (SPE).

Methods: Thirty-six patients (16 males and 20 females; mean age, 51.

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Attenuation correction is widely used in SPECT/CT (Single Photon Emission Computed Tomography) procedures, especially for imaging of the thorax region. Different compensation methods have been developed and introduced into clinical practice. Most of them use attenuation maps obtained using transmission scanning systems.

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Background: This study investigated the effect of temporary occlusion of the aorta on the development of ischemia-reperfusion (I/R) injury of the visceral organs, the optimal timing of administration of resveratrol, and its mechanism of protection via inhibiting nitric oxide (NO) release with an NO synthase inhibitor.

Methods: Rabbits were divided into seven groups according to the administration period of resveratrol and/or N(G)-nitro-L-arginine methyl ester (L-NAME): control group; group 1, resveratrol during ischemic period; group 2, resveratrol during reperfusion period; group 3, L-NAME during ischemic period; group 4, L-NAME during reperfusion period; group 5, resveratrol during ischemic period and L-NAME during reperfusion period; group 6, L-NAME during ischemic period and resveratrol during reperfusion period. The infrarenal aorta was clamped for 30 min.

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Postoperative neurologic deficit is the most devastating complication after thoracoabdominal aortic aneurysm repair. Our aim was to investigate whether nebivolol has protective effects during ischemia or reperfusion and the most effective mechanism of protection via inhibiting nitric oxide (NO) release with an NO synthase inhibitor in an experimental model of spinal cord ischemia/reperfusion injury. Spinal cord ischemia was induced by occlusion of the infrarenal aorta for 30 min.

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Background And Aim Of The Study: The new calcium sensitizer, levosimendan, not only acts as a positive inotropic agent but also, vasodilates both venules and arterioles. The aim of this experimental study was to investigate whether levosimendan has protective effects on spinal cord ischemia-reperfusion injury.

Material And Methods: Twelve New Zealand rabbits were enrolled in this study.

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The aim of this experimental study was to investigate whether dimethylsulfoxide (DMSO) has protective effects on spinal cord ischemia-reperfusion (I/R) injury. New Zealand rabbits were enrolled in the study. In addition to the control group, the study group received 0.

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Objective: The aim of this study was to investigate the response of heart to stress according to the size of the prosthetic valve in patients who had undergone mitral valve replacement by using dobutamine stress echocardiography (DSE) and to evaluate the relationship between the size of the prosthetic valve and cardiac recovery-remodeling process.

Methods: Thirty-nine patients, who had undergone mitral valve replacement were compared in terms of left ventricular diameters, systolic functions and cardiac mass indexes in order to investigate the effect of the mechanical valve size on postoperative cardiac remodeling in this longitudinal study. They were divided into three groups according to their valve size: Group 1 (valve size<29 mm, n=11), Group 2 (valve size=29 mm, n=11) and Group 3 (valve size>29 mm, n=17).

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Objective: The study aim was to investigate the effect of blood glucose level on atherosclerotic lesion distribution and the contribution to the operative mortality/morbidity in diabetic patients who underwent coronary artery bypass grafting (CABG).

Methods: Between 1986-2003, a total of 2095 patients with diabetes mellitus underwent CABG. The analysis was carried out retrospectively from the clinical records.

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The periods of ischemia and reperfusion represent different characteristics by lack of oxygen and reoxygenation. The aim of this experimental spinal cord injury model was to investigate whether resveratrol has protective effects during ischemia or reperfusion and the mechanism of the protection by using N-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide synthase. Rabbits were divided into seven groups according to the time of administration of resveratrol or L-NAME (RI and RR, resveratrol during ischemia or reperfusion; IL and RL, L-NAME during ischemia or reperfusion; RILR, resveratrol during ischemia and L-NAME during reperfusion; LIRR, L-NAME during ischemia and resveratrol during reperfusion; control group).

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Aim: The aim of this study was to investigate the differences in cardiac response to stress according to the size of the prosthetic valve in patients who underwent aortic valve replacement (AVR) and to evaluate the relationship between the size of the prosthetic valve and cardiac recovery-remodeling after the operation.

Methods: Thirty patients who had undergone AVR (12 patients) or double valve replacement (18 patients) underwent dobutamine-stress echocardiography 4.2 years after the operation to evaluate response to stress .

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A 10-year-old girl underwent tetralogy of Fallot (TOF) repair and subsequent pulmonary valve replacement with a St. Jude Medical mechanical heart valve prosthesis. Valve replacement was necessary due to right heart failure resulting from pulmonary regurgitation occurring three months after TOF repair.

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Changes at the level of gene expression are becoming an increasingly recognized component of the neuronal response to injury. We used Northern analysis and three in vivo models of central nervous system (CNS) injury in the rat to determine whether injury alters the expression of certain gene products related to cellular homeostasis. The three models included kainate (KA)-induced seizures, global ischemia, and lateral fluid percussion injury to the cerebral cortex.

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The efficacy of monosialoganglioside GM1 treatment was evaluated in a model of experimental stroke. Cerebral ischemia was induced by permanent occlusion of left middle cerebral artery. GM1 was administered intravenously soon after the occlusion of the artery and then intramuscularly daily for 7 days.

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The efficacy of p.o. semisynthetic glycolipid LIGA20 (II3Neu5-AcGgOse4-2-d-erythro-1,3-dihydroxy-2-dichloro-aceta mide-4-trans- octadecene) treatment in stroke was studied in a permanent left middle cerebral artery occlusion model in the rat.

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Synaptic reorganization occurs in the hippocampus following various forms of seizure activity and injury, and may contribute to epileptogenesis. To address the hypothesis that neurotrophic factors play an inductive role in synaptic reorganization following seizures, we directly measured neurotrophic activity in rat hippocampal extracts after kainate injection or prolonged stimulation of the perforant path. Serial dilutions of hippocampal extracts were added to cultures of chick dorsal root ganglia, which are known to require trophic support from nerve growth factor and other neurotrophins, or ciliary ganglia neurons, which require trophic support from ciliary neurotrophic factor.

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A focal, unilateral thrombotic stroke was produced in the rat sensorimotor cortex. The time course of expression and localization of the immediate early inducible genes: c-fos, c-jun, zif268; nerve growth factor, brain-derived neurotrophic factor and the related tyrosine kinase high-affinity receptor (trkB) messenger RNAs were studied by in situ hybridization. The levels of messenger RNAs for c-fos, zif268, brain-derived neurotrophic factor (but not nerve growth factor) and trkB were consistently increased in cortex ipsilaterally to the lesion, while c-jun messenger RNA content was only slightly increased.

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