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Öğe Acute Subdural Hematomas Caused by Ruptured Aneurysms: Experience from a Single Turkish Center(Turkish Neurosurgical Soc, 2009) Kocak, Ayhan; Ates, Ozkan; Durak, Akif; Alkan, Alpay; Cayli, Suleyman; Sarac, KayaAIM: Although an aneurysmal rupture typically presents on computed tomography (CT) imaging as only a subarachnoid hemorrhage (SAH), it may be associated with spontaneous (nontraumatic) subdural hemorrhage (sSDH). The purpose of this paper is to discuss the clinical and radiological characteristics, as well as a potentially dangerous situation in the diagnosis and the management of this life-threatening condition. MATERIAL and METHODS: The Department of Neurosurgery at Inonu University (Turgut Ozal Medical Center) (TOMC) maintains a prospective database of all patients treated for intracranial aneurysms since 1999. Using this database, we obtained patients with ruptured aneurysms who presented with sSDH on CT imaging. RESULTS: 687 patients with radiographically documented ruptured aneurysms were admitted from January 2000 through January 2009. Of these, eleven patients presented with sSDH. The incidence of aneurysmal rupture with sSDH is 1.6% in our series. CONCLUSION: Acute sSDH on cranial CT should be considered for an urgent workup of a ruptured aneurysm, even in the absence or presence of SAH finding. CT angiography has advantages over cerebral digital substraction angiography (DSA) and may be a reasonable alternative to latter modality in the diagnosis, triage, and treatment planning in patients with sSDH.Öğe Do we damage nucleus pulposus tissue while treating cerebrovascular ischemic neurological deficits with nimodipine?(2018) Karaarslan, Numan; Yilmaz, Ibrahim; Yasar Sirin, Duygu; Baykiz, Derya; Demirkiran, Aykut; Ates, OzkanAim: Nimodipine is used to prevent cerebrovascular-originated ischemic neurological deficits, yet its effects on nucleus pulposus (NP) cells or annulus fibrosus (AF) cells weren’t studied. This study aimed to examine nimodipine’s effects on vitality and proliferation of chondroadherin (CHAD), type II collagen (COL2A1), and hypoxia-inducible factor 1 alpha (HIF 1α) gene expression in human primary NP/AF cells. Material and Methods: NP/AF cell cultures obtained from 6 patients who underwent microdiscectomy were treated with 100 µMolar nimodipine and analyzed at 0, 24, and 48 h. Data were evaluated using one-way ANOVA and post-hoc Tukey HSD with 95% confidence interval. Results: We observed suppressed cell proliferation and increased necrosis in nimodipine-treated NP/AF cell cultures, especially degenerated tissue. COL2A1 gene expression wasn’t detected in any experimental groups. CHAD and HIF 1α expression had timedependent decreases in control. CHAD and HIF 1α expression were found to decrease at 24h, but increased at 48h in degenerated tissue. In nimodipine-applied intact tissues, CHAD expression was stable at 24h but 1.62 times higher than control at 48h. HIF 1α levels were lower than control. Conclusion: In nimodipine-treated degenerated AF/NP cultures, CHAD and HIF 1α expressions had time-dependent decreases. However, after complete RT-PCR data evaluation, no correlation between nimodipine application and gene expression occurred.Öğe Does transcription factor, induced by daptomycin and vancomycin, affect HIF-1α, Chondroadherin, and COL2A1?(2018) Karaarslan, Numan; Yilmaz, Ibrahim; Yasar Sirin, Duygu; Ozbek, Hanefi; Kaya, Yasin Emre; Akyuva, Yener; Kaplan, Necati; Dogan, Mustafa; Gumustas, Seyit Ali; Erdem, Ilknur; Ates, OzkanAim: In this study, it was firstly aimed to investigate the effect of Daptomycin (DAP) on the proliferation in Vancomycin (VCM)- administered primary chondrocyte cultures and non-drug-administered primary chondrocyte cultures. Our second objective was to investigate the effects of DAP and VCM on the NP-specific marker protein chondroadherin (CHAD), which is associated with spinal cord and dorsal column growth, on the transcription factor-1 alpha (HIF-1α), which is induced by hypoxia, and on a type II collagen (COL2A1), which is also known to play a significant role in the development of extracellular matrix, at the pharmaco-molecular level. Material and Methods: Standard human primary chondrocyte cultures were established. DAP and VCM were added to the samples. In all groups, molecular analysis was performed at 0th, 24th and 48th hours. In addition, the surface morphology of the cells was evaluated. Results: Changes in cell morphology and cell death in cultures were observed 24 hours after administration of antibiotics to cell cultures. It was observed that drug administration was associated with the cell viability and that cell viability rate for two antibiotics was similar at the 0th and 48th hours. The expression of three genes decreased at the 24th hour in the experimental group where DAP was administered. Conclusion: Thanks to this molecular-based research, it should not be forgotten that DAP and VCM active pharmacological agents, especially used in the treatment of Methicillin-resistant Staphylococcus aureus induced surgical infections, have a negative effect on human chondrocyte and ECM components.Öğe Evaluation of neutrophil-to-lymphocyte ratio as a marker of inflammatory response in spondylodiscitis(2018) Karaarslan, Numan; Yilmaz, Ibrahim; Caliskan, Tezcan; Akgun, Feride Sinem; Bilir, Bulent; Dogan, Mustafa; Ates, OzkanAim: Spondylodiscitis, if not diagnosed on time, can cause morbidity or mortality at high rates. This study was carried out with the aim of testing the hypothesis that “neutrophil-to-lymphocyte ratio can be used” especially in cases where it is difficult to diagnose spondylodiscitis. Material and Methods: This study involved 24 patients admitted to the State Hospital of Ministry of Health and Namik Kemal University for spondylodiscitis between January2014 and June2017. After excluding the cases that did not meet the inclusion criteria (n=6), the remaining cases (n=24) were referred to as the study group. A control group was created from healthy volunteers (n=24) who applied for routine physical checkups at the clinic between the same dates and who were similar in terms of age, sex, and body mass index to the study group. Hemogram parameters of the cases in both groups; white blood cell, C-reactive protein, erythrocyte sedimentation rate, and neutrophil-to-lymphocyte ratio were statistically compared. Results: Patients in the spondylodiscitis group, compared to healthy volunteers had statistically significant neutrophil-to-lymphocyte ratio value. Conclusion: Especially in cases where the diagnosis of spondylodiscitis is not assured, the neutrophil-to-lymphocyte ratio parameter, which is less costly than other diagnostic methods and the analysis results of which can be obtained in a shorter time, may be used to support clinical diagnosis.Öğe Evaluation of the effect of apixaban on the primary intact intervertebral disc cell cultures(2019) Akgun, Feride Sinem; Karaarslan, Numan; Yilmaz, İbrahim; Ozbek, Hanefi; Yasar Sirin, Duygu; Simsek, Abdullah Talha; Kaplan, Necati; Ates, OzkanAim: Apixaban is a frequently preferred pharmacological agent in clinics to prevent deep vein thrombosis and pulmonary embolism. Such new oral anticoagulants may cause hemorrhage’s in tissues and/or organs or may cause gastrointestinal symptoms without bleeding. It is also reported in the literature that it may lead to mental disorders, unwanted disorders in the urinary tract and skeletal-muscle system. However, when the literature is examined, there are no studies, which are of high-evidential value, evaluating the efficacy of apixaban on healthy, intact intervertebral disc tissue, and matrix-like structures. In this pharmaco-molecular study, it was aimed to investigate the effects of a new oral anticoagulant agent containing the active ingredient apixaban on the intact intervertebral disc tissue cells, extracellular matrix (ECM) structure and to evaluate its positive and / or negative effects on gene expressions of cartilage oligo matrix protein (COMP), chondroadherin (CHAD), and Matrix Metalloproteinase (MMP)s.Material and Methods: The primary cell cultures were prepared from the intact tissues of the patients with the traumatic intervertebral disc herniation. Apixaban was administered to the cultures and molecular analyses were performed for 21 days. The data obtained from the apixaban-administered and non-apixaban-administered samples were evaluated statistically and the significance value was accepted as P 0.05.Results: The changes were observed in the cell proliferation and the expressions of the mentioned genes in the apixaban-administered group. The suppression of COMP value and the increase in MMP-13 value may be indicative of the development of matrix degeneration in the apixaban-administered group, compared to the non-drug-administered control group. Conclusion: The selectivity is one of the most important features of the drugs. However, it should not be forgotten that no drug will only produce the desired effect.Öğe Investigation of the effects of tigecycline, a semi-synthetic derivative of minocycline, on chondrocyte cultures(2020) Kaya, Yasin Emre; Karaarslan, Numan; Yilmaz, İbrahim; Yasar Sirin, Duygu; Yaman, Onur; Ozbek, Hanefi; Ates, OzkanAim: Although antibiotics are generally well-tolerated, they may have cytotoxic effects. The present randomized, double-blind, in vitro study aimed to investigate the effects of tigecycline on cartilage tissue cells and the extracellular matrix.Material and Methods: Cartilage tissues of patients (n = 8) were used for the preparation of primary cell cultures. Tigecycline-treated cell cultures served as the study group. Non-treated cell cultures served as the control group. Analyses were performed at 0, 24, 48, and 72 h in both groups. The results obtained were statistically evaluated. The alpha significance value was determined to be 0.05.Results: Proliferation remained unchanged in the tigecycline-treated cell cultures. The gene expressions of the markers involved in anabolic pathways increased in the tigecycline-treated cell cultures. The results obtained were statistically significant (P 0.05). Conclusion: Although tigecycline had no toxic effect on the chondrocyte cell cultures and caused no damage to the extracellular matrix, the present study was performed in an in vitro environment.Öğe Isolated internal auditory artery aneurysm(Elsevier Sci Ltd, 2008) Kocak, Ayhan; Sarac, Kaya; Ates, Ozkan; Cayli, Suleyman Rustu; Kutlu, RamazanAnticoagulant therapy is effective and prevents death in more than 95% of patients with pulmonary embolism following deep vein thrombosis. We report a patient who developed deep vein thrombosis following rupture of a dissecting aneurysm of the internal auditory artery. The parent artery was occluded before anticoagulant therapy as a prophylactic measure to prevent intracranial haemorrhage. We discuss some of the clinical features, therapeutic difficulties, and pitfalls in the management of internal auditory artery aneurysm complicated by deep vein thrombosis. (C) 2007 Elsevier Ltd. All rights reserved.Öğe Neuroprotective effect of etomidate on functional recovery in experimental spinal cord injury(Pergamon-Elsevier Science Ltd, 2006) Cayli, Suleyman R.; Ates, Ozkan; Karadag, Nese; Altinoz, Eyup; Yucel, Neslihan; Yologlu, Saim; Kocak, AyhanObjective: Primary impact to the spinal cord causes rapid oxidative stress after injury. To protect neural tissue, it is important to prevent secondary pathophysiological mechanisms. Etomidate, a strong antiexcitotoxic agent, stimulates the gamma aminobutyric acid (GABA) receptors. The purpose of this study was to investigate neurobehavioral and histological recovery and to evaluate the biochemical responses to treatment of experimental spinal cord injury (SCI) in rats with etomidate or methylprednisolone (MP) or both etomidate and MP. Material and methods: Seventy-two rats were randomly allocated into six groups: a control group (laminectomy alone), a trauma group (laminectomy + trauma), a methylprednisolone group (30 mg/kg MP), an etomidate group (2 mg/kg), a methylprednisolone, and etomidate combined treatment group (30 mg/kg MP and 2 mg/kg etomidate) and a vehicle group. Six rats from each group were killed at the 24th hour after the injury. Malondialdehyde, glutathione, nitric oxide and xanthine oxidase levels were measured. Neurological functions of the remaining rats were recorded weekly. Six weeks after injury, all of those rats were killed for histopathological assesssment. Conclusion: Etomidate treatment immediately after spinal cord injury has similar neuroprotection to MR In spite of different neuroprotection mechanisms, combined treatment with MP and etomidate does not provide extra protection. (c) 2006 ISDN. Published by Elsevier Ltd. All rights reserved.Öğe Neuroprotective effect of mexiletine in the central nervous system of diabetic rats(Springer, 2006) Ates, Ozkan; Cayli, Suleyman R.; Altinoz, Eyup; Yucel, Neslihan; Kocak, Ayhan; Tarim, Ozcan; Durak, AkifBoth experimental and clinical studies suggests that oxidative stress plays an important role in the pathogenesis of diabetes mellitus type I and type 2. Hyperglycaemia leads to free radical generation and causes neural degeneration. In the present study we investigated the possible neuroprotective effect of mexiletine against streptozotocin-induced hyperglycaemia in the rat brain and spinal cord. 30 adult male Wistar rats were divided into three groups: control, diabetic, and diabetic-mexiletine treated group. Diabetes mellitus was induced by a single injection of streptozotocin (60 mg/kg body weight). Mexiletine (50 mg/kg) was injected intraperitoneally every day for six weeks. After 6 weeks the brain, brain stem and cervical spinal cord of the rats were removed and the hippocampus, cortex, cerebellum, brain stem and spinal cord were dissected for biochemical analysis (the level of Malondialdehide [MDA], Nitric Oxide [NO], Reduced Glutathione [GSH], and Xanthine Oxidase [XO] activity). MDA, XO and NO levels in the hippocampus, cortex, cerebellum, brain stem and spinal cord of the diabetic group increased significantly, when compared with control and mexiletine groups (P < 0.05). GSH levels in the hippocampus, cortex, cerebellum, brain stem and spinal cord of the diabetic group decreased significantly when compared with control and mexiletine groups (P < 0.05). This study demonstrates that mexiletine protects the neuronal tissue against the diabetic oxidative damage.