Publications by authors named "Serhat Erbayraktar"

Study Design: Retrospective case series.

Objectives: We aimed to describe with a novel surgical approach for the removal of posterior thoracolumbar implant in patients with symptomatic failure of the implant and present our preliminary results with this method.

Methods: This retrospective, single-center study was performed in the neurosurgery department of a university hospital.

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This study aims to compare the effects of osteoplastic craniotomy on temporalis muscle and bone graft atrophy in patients operated on with a pterional approach to the standard technique. Patients operated on for an intracranial aneurysm with a pterional approach between 2014 and 2018 were studied. Following the exclusion criteria, 36 patients were included in this retrospective study.

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Background: Current methods used to measure the muscle strength required to achieve plantar flexion may yield highly variable results depending on the perception of the physician conducting the examination because these tests involve subjective and qualitative evaluation.

Objective: To describe and evaluate the efficacy of a novel examination technique that can quantitatively measure plantar flexion in L5-S1 disc herniation.

Materials And Methods: A total of 32 patients (average age: 49.

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Objective: Pedicle screw loosening and fractures of instrumented vertebrae are not uncommon and require reoperations, which are an immense burden on the patient and health care system. We aimed to describe a novel, simple percutaneous technique on instrumented vertebrae for treating pedicle screw loosening and demonstrate that corpus with osteoporotic vertebral compression fractures can be managed with this simple technique.

Methods: This retrospective study was performed using data gathered from 15 patients who underwent transforaminal vertebroplasty due to symptomatic pedicle screw loosening and vertebral body fracture between 2020 and 2021.

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Background: The aim of this retrospective study was to describe a novel, simple surgical technique for the treatment of symptomatic Tarlov cysts.

Methods: A total of 40 patients with symptomatic Tarlov cysts, admitted to our tertiary center between 1998 and 2019 constituted the study group. All patients underwent microsurgical puckering of the cyst, the technique we described to prevent a recurrence.

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Objective: Ependymomas are neuroepithelial tumors of the central nervous system with heterogeneous biology and clinical course. The aim of the present study is to investigate the relationship between the methylation status and clinicopathological parameters in ependymomas.

Material And Method: DNA methylation status of CDKN2A, RASSF1A, KLF4 and ZIC2 genes were quantitatively analyzed with pyrosequencing in 44 ependymoma tumor tissues.

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Although the close relationships between most of the trace elements and tumor formation mechanisms are very well-defined, studies on some elements such as zinc are still ongoing. When examining studies on brain tumors, it was observed that studies investigating the role played by serum zinc levels on tumor etiology and prognosis have gained momentum. In this study, we investigate the relationship between different brain tumor types and serum zinc levels by quantitatively analyzing serum zinc levels in patients with primary brain tumors.

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Background: The aim of this study was to investigate the effects of intracerebroventricularly administered rocuronium bromide on the central nervous system, determine the seizure threshold dose of rocuronium bromide in rats, and investigate the effects of rocuronium on the central nervous system at 1/5, 1/10, and 1/100 dilutions of the determined seizure threshold dose.

Methods: A permanent cannula was placed in the lateral cerebral ventricle of the animals. The study was designed in two phases.

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Background: The aim of this study was to investigate the effects of intracerebroventricularly administered rocuronium bromide on the central nervous system, determine the seizure threshold dose of rocuronium bromide in rats, and investigate the effects of rocuronium on the central nervous system at 1/5, 1/10, and 1/100 dilutions of the determined seizure threshold dose.

Methods: A permanent cannula was placed in the lateral cerebral ventricle of the animals. The study was designed in two phases.

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Objective: In this study, the antiarrhythmic and anti-ischemic effects of a 6 μg kg(-1) min(-1) infusion dose of remifentanil are investigated in a central sympathetic hyperactivity model in rabbits.

Methods: In this study, 18 New Zealand rabbits were used. The subjects were randomly divided into three groups (n=6) and received 10 μmol L(-1) glutamate intracerebroventricularly to provide the central sympathetic hyperactivity.

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Animal models are important to develop therapies for individuals suffering from spinal cord injuries. For this purpose, rats are commonly preferred. In sharp injury models, spinal cord is completely or incompletely cut to assess axonal regeneration.

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Erythropoietin (EPO) is a neuroprotective cytokine in models of ischemic and nervous system injury, where it reduces neuronal apoptosis and inflammatory cytokines and increases neurogenesis and angiogenesis. EPO also improves cognition in healthy volunteers and schizophrenic patients. We studied the effect of EPO administration on the gene-expression profile in the ischemic cortex of rats after cerebral ischemia at early time points (2 and 6 h).

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Aim: The aim of our study was to examine the effects of the use of Transcutaneous Electrical Nerve Stimulation (TENS) in patients who had undergone spinal surgery on pain, functionality, depression and consumption of analgesic agents.

Material And Methods: Fifty-Four patients were randomized and placed into two groups, patient-controlled analgesia (PCA) plus TENS and only PCA. To assess the pain levels of the patients, the Visual Analog Scale (VAS) was used.

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Erythropoietin (EPO) is a type I cytokine that utilizes different receptor isoforms either to maintain hematopoiesis or protect against injuries that arise from widely diverse etiologies. EPO also facilitates healing by reducing inflammation and mobilizing endothelial progenitor cells to participate in restorative neoangiogenesis, but it is unclear which EPO receptor isoform is responsible for healing and whether this receptor use varies according to the type of wound. In the present studies carried out in the rat, we have utilized receptor-selective derivatives of EPO to determine which receptor type operates in (i) a nonischemic wound (skin punch biopsy), (ii) a permanently ischemic wound (raised musculocutaneous flap), (iii) an intermittent ischemic reperfusion wound (pressure or decubitus ulcer), or (iv) wounds complicated by infection (cecal ligation and perforation).

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Objective: We evaluated the level of pain, disability, performance, and physical activity changes in patients who underwent lumbar disc hernia surgery.

Methods: This study included 31 patients who underwent lumbar disc hernia surgery in the Neurosurgery Department of Dokuz Eylul University Hospital, Izmir, Turkey over a 13-month period from April 2003 to May 2004. Changes in the patients` pain were determined using a visual analog scale, and disability changes were evaluated using the Oswestry Disability Index.

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Erythropoietin (EPO), a member of the type 1 cytokine superfamily, plays a critical hormonal role regulating erythrocyte production as well as a paracrine/autocrine role in which locally produced EPO protects a wide variety of tissues from diverse injuries. Significantly, these functions are mediated by distinct receptors: hematopoiesis via the EPO receptor homodimer and tissue protection via a heterocomplex composed of the EPO receptor and CD131, the beta common receptor. In the present work, we have delimited tissue-protective domains within EPO to short peptide sequences.

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Previous studies have shown that erythropoietin (EPO) has protective effects against ischemia/reperfusion (I/R) injury in several tissues. The aim of this study was to determine whether EPO could prevent intestinal tissue injury induced by I/R. Wistar rats were subjected to intestinal ischemia (30 min) and reperfusion (60 min).

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Gamma knife radiosurgery is an attractive noninvasive treatment of brain tumors and vascular malformations that minimizes collateral tissue damage. However, exposure of normal tissue to even low-dose radiation triggers a cascade of acute and chronic injury and potentially significant morbidity and mortality. Because many irradiated patients now survive for years, identifying methods to prevent radiotherapy-induced collateral tissue damage is a major focus of current research.

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Background: The aim of this study is to measure and compare the in vivo intraaneurysmal pressures of experimental lateral wall aneurysms, before and after onyx embolization. The data of this experiment will carry an important role in forming the scientific basis for the clinical endovascular applications.

Materials And Methods: Five experimental lateral wall aneurysms were created by microsurgical techniques in 5 New Zealand rabbits' right common carotid arteries.

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Object: Spinal cord injury (SCI) is a devastating clinical syndrome for which no truly efficacious therapy has yet been identified. In preclinical studies, erythropoietin (EPO) and its nonerythropoietic derivatives asialoEPO and carbamylated EPO have markedly improved functional outcome when administered after compressive SCI. However, an optimum treatment paradigm is currently unknown.

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Erythropoietin (EPO) is both hematopoietic and tissue protective, putatively through interaction with different receptors. We generated receptor subtype-selective ligands allowing the separation of EPO's bioactivities at the cellular level and in animals. Carbamylated EPO (CEPO) or certain EPO mutants did not bind to the classical EPO receptor (EPOR) and did not show any hematopoietic activity in human cell signaling assays or upon chronic dosing in different animal species.

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As far as the prognosis is concerned, it is important to diagnose the exact type of congenital cystic adenomatoid malformation (CCAM) in order to exclude associated anomalies, as well as the risk of development of malignancies in later life. The frequency of associated malformations of CCAM type 4 is unknown. We report a 4-month-old boy with CCAM type 4 and aneurysmal malformation of the vein of Galen (AVG).

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