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Dive into the research topics where Ramazan Durmaz is active.

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Featured researches published by Ramazan Durmaz.


Clinical Neurology and Neurosurgery | 1997

Management of glioblastoma multiforme: with special reference to recurrence

Ramazan Durmaz; Suavi Erken; Ali Arslantas; Metin Ant Atasoy; Cengiz Bal; Esref Tel

Between 1985 and 1995, 46 patients underwent craniotomy for glioblastoma multiforme. The mean age was 47, varying from 9 to 71 years. The influence of such prognostic factors as age, preoperative Karnofsky score, extent of resection, tumour site, tumour size, radiotherapy, reoperation as well as initial symptoms upon survival were studied. Of these, gross complete removal, radiotherapy, preoperative Karnofsky score, and reoperation were shown to be statistically significant to the survival time according to logrank and univariate tests. However, age, preoperative Karnofsky score, tumour size and temporal localisation remained as significant factors in multivariate analysis. The overall median survival was 53 weeks, with no patients surviving more than 3 years. Of the patients, 41% survived over a year and 8.6% lived over two years. Twenty-six patients developed a recurrent mass after an interval of 32 weeks. The median interval time from operation to recurrence was longer in those patients who underwent gross removal than in those who had a subtotal resection, 28.2 against 20 weeks (P < 0.05). Of patients who had a recurrent mass, 16 were reoperated on, with a subsequent median survival time of 26.5 weeks. Our experience suggests that the survival of patients with glioblastoma depends on many factors, including radical surgery as an initial step. In addition, the gross total removal of the tumour also delays the development of recurrence.


Neurosurgical Review | 2004

The importance of genomic copy number changes in the prognosis of glioblastoma multiforme

Ali Arslantas; Sevilhan Artan; Ülkü Öner; Hamza Müslümanoglu; Ramazan Durmaz; Erhan Cosan; Metin Ant Atasoy; Nurettin Basaran; Esref Tel

Glial tumors are the most common tumors of the nervous system, affecting individuals at any age. Since understanding of the molecular pathologies underlying human gliomas is still very poor, the treatment and therefore prognosis of this malignancy could not yet be improved. In order to determine whether different glioblastoma-associated genomic aberrations may serve as prognostic markers in combination with histopathological findings, 20 primary glioblastoma multiforme tumors were screened by comparative genomic hybridization, and the results were compared with histopathological and clinical features. All tumors showed genomic copy aberrations detected by comparative genomic hybridization. Regional and numerical increases in chromosome 7 copy number were the most frequently seen abnormality (10/20 tumors), followed by loss of chromosome 10 (8/20). Both of these aberrations were associated with shorter surveillance time. Chromosome 12q amplification was detected in seven tumors. Loss of 17p, 1p, and 19q in combination was seen in three cases. One of them was a giant cell GBM, whereas the remaining two cases were still alive. Combination of chromosome 1p and 19q deletions was also seen in a case with long surveillance. According to the preliminary findings of this study, in addition to the EGFR gene, amplification of other genes on chromosome 7 and the deletion of PTEN gene and other cancer-related genes on chromosome 10 appeared important to the development of glioblastoma multiforme and were associated with poor prognosis, whereas the combination of chromosome 1p and 19q deletions seems to be an informative molecular marker for better prognosis. The clinical features and genetic alterations of primary and secondary glioblastoma multiforme should be compared in large series to clarify the effective prognostic markers; and further molecular analyses focused on chromosomes 7 and 10 will be very helpful for understanding the molecular mechanisms underlying the progression of glioblastoma.


Pathology & Oncology Research | 2007

Genomic alterations in low-grade, anaplastic astrocytomas and glioblastomas.

Ali Arslantas; Sevilhan Artan; Ülkü Öner; M. Hamza Müslümanoglu; Muhsin Özdemir; Ramazan Durmaz; Didem Arslantas; Murat Vural; Erhan Cosan; Metin Ant Atasoy

To extend our understanding of potential stepwise genetic alterations that may underlie tumor progression from low-grade astrocytomas to glioblastomas, histopathologic and comparative genomic hybridization analyses were performed on tumor specimens from 68 primary lesions, including 40 glioblastomas, 10 anaplastic and 18 low-grade astrocytomas. The number of aberrations per case increased towards the higher grade tumors (grade II: 1.66±1.49; grade III: 2.80±1.68; grade IV: 3.02±1.07; F=6.955, p=0.002). A gain of 7/7q was common and the most frequently seen aberration in low-grade astrocytomas, whereas loss of 10q was the most frequently seen anomaly in anaplastic astrocytomas and glioblastomas. Chromosome 7p amplification was only detected in glioblastomas. Chromosome 10/10q deletion and combination of lp, 19q and 17p deletions were specific to high-grade astrocytic tumors. Sequences of chromosome 7 and 10 seem to have pivotal roles in the biology of human gliomas. The genomic copy deletions of chromosomes lp and 19q might provide an alternative mechanism in the genesis of astrocytomas.


Clinical Neurology and Neurosurgery | 2001

Multiple nocardial abscesses of cerebrum, cerebellum and spinal cord, causing quadriplegia

Ramazan Durmaz; Metin Ant Atasoy; Gül Durmaz; Baki Adapinar; Ali Arslantas; Aydin Aydinli; Esref Tel

In this paper we present a case of a diabetic patient with nocardial abscesses of cerebrum, cerebellum and the spinal cord. The present case is the first case in the literature of solitary intramedullary abscess in cervical spinal cord, causing tetraplegia. Nocardia asteroides grew in a culture of the abscess pus. After either surgical excision or drainage of lesions, a triple combination regimen of chemotherapy (amikacin, ceftriaxone and trimethoprim-sulfamethoxazole) was given, but the patient was lost in the postoperative period. This case gives suggestive evidence of an association between cervical spinal cord involvement and poor prognosis in CNS nocardiosis.


Canadian Journal of Neurological Sciences | 2003

Lazaroid attenuates edema by stabilizing ATPase in the traumatized rat brain

Ramazan Durmaz; Güngör Kanbak; Fahrettin Akyüz; Serap Isiksoy; Ferruh Yücel; Mine İnal; Esref Tel

OBJECTIVE The aim of the present study was to determine the potential therapeutic value of the lazaroid U-83836E on blood brain barrier (BBB) breakdown and edema with respect to the changes in the synaptosomal Na+/K+ and Mg(2+)/Ca(2+)-adenosinetriphosphatase (ATPase) activities, tissue malondialdehyde levels and the neuronal viability in the rat brain subjected to cerebral trauma. METHODS Traumatic brain injury (TBI) was introduced by applying a 75 gm. cm force to the right parietal cortex using the weight-drop method. The first set of animals was used for determining time course changes of the synaptosomal Na+/K+ and Mg(2+)/Ca(2+)-ATPase and the malondialdehyde levels and were sacrificed 2, 6 and 24h after lesion production. A group of the animals was treated with U-83836E proir to TBI and sacrificed 24h after cerebral injury. A second set of animals was used for evaluating the alterations in BBB disruption and tissue water content and were sacrificed 2, 6 and 24h after lesion production. Two groups of animals were treated with U-83836E and sacrificed after 2 and 24h following TBI. U-83836E was given intraperitoneally thirty minutes before trauma at a dose of 10 mg/kg. Neuronal necrosis was also evaluated in the groups of U-83836E and physiological saline-treated animals. RESULTS Extravasation of Evans blue into the traumatized hemisphere was maximum at 2h (p<0.001) and returned close to the control levels at 24h after TBI (p>0.05). Edema had developed progressively over time and reached the maximum degree of 2.1% (p<0.001) at 24h. U-83836E showed no effect on the BBB breakdown and the tissue water content at 2h and still had no effect on the BBB breakdown after 24h following the trauma (p>0.05), although it reduced edema after 24h (p<0.01). The losses of Na+/K+ and Mg(2+)/Ca(2+)-ATPase activities were found as 39.5% (p<0.001) and 29.4% (p<0.01) of the control value, respectively, and remained at the decreased levels throughout the experiment. Malondialdehyde level continued to increase over time reaching up to 209% (p<0.001) of the control value 24h after TBI. Both ATPase activities were improved to near control values (p>.05) by the effect of U-83836E. U-83836E inhibited the increase of lipid peroxidation (p<0.001) and also salvaged neuronal necrosis (p<0.05). CONCLUSION U-83836E given prophylactically after cerebral trauma appears to reduce edema, possibly by inhibiting increases in lipid peroxidation and by stabilizing ATPase. Further studies are recommended to verify the similar effects of the brain penetrating lazaroids when they are given after trauma.


Childs Nervous System | 2001

Inadvertent insertion of a nasogastric tube in a patient with head trauma

Ali Arslantas; Ramazan Durmaz; Erhan Cosan; Esref Tel

Abstract This is a report of a 3-year-old boy with intracranial penetration of a nasogastric tube causing brain damage in the left frontal lobe. A computed tomography (CT) showed passage of the nasogastric tube via a fracture of the cribriform plate into the intracranial cavity. The tube was manually removed under antibiotic prophylaxis. The patient then underwent dural repair for rinorrhoea and was discharged in good health.


Gene | 2013

The neuroprotective effect of acute moderate alcohol consumption on caspase-3 mediated neuroapoptosis in traumatic brain injury: The role of lysosomal cathepsin L and nitric oxide

Güngör Kanbak; Kazim Kartkaya; Eda Ozcelik; Ahmet Burak Guvenal; Sibel Canbaz Kabay; Gul Arslan; Ramazan Durmaz

Our aim in this study was to investigate the effect of moderate acute alcohol administration on cysteine protease mediated neuronal apoptosis and nitric oxide production in the traumatic brain injury. A total of 29 adult Sprague-Dawley male rats weighing 250-300 g were used. The rats were allocated into four groups. The first group was the control (sham-operated) group in which only a craniotomy was performed, the others were alcohol, trauma and trauma+alcohol groups. Caspase-3 enzyme activity in the trauma group increased significantly in comparison with the control group. The alcohol given group showed a decreased caspase-3 enzyme activity compared to the trauma group. The level of caspase-3 enzyme activity in the alcohol+trauma group decreased in comparison to the trauma group. SF/FEL ratio of cathepsin-L enzyme activity in the trauma group was significantly higher than in the control group. Our results indicate that moderate alcohol consumption may have protective effects on apoptotic cell death after traumatic brain injury. Protective effects of moderate ethanol consumption might be related to inhibition of lysosomal protease release and nitric oxide production.


Journal of the Neurological Sciences | 2003

Lazaroid U-74389G attenuates edema in rat brain subjected to post-ischemic reperfusion injury

Ramazan Durmaz; Kemal Ertilav; Fahrettin Akyüz; Güngör Kanbak; Kismet Bildirici; Esref Tel

The aim of the present study was to determine the potential therapeutic value of 21-aminosteroid U-74389G, on blood-brain barrier (BBB) breakdown and edema in association with the changes in synaptosomal Na(+)/K(+) and Mg(2+)/Ca(2+)-ATPase activities in rat brain subjected to post-ischemic reperfusion injury. Brain ischemia was achieved by means of four-vessel occlusion model for 25 min and animals were sacrificed after 12 h reperfusion. An increase of cerebral tissue water content, blood-brain disruption and the changes of synaptosomal Na(+)/K(+) and Mg(2+)/Ca(2+)-ATPases activities were evaluated. U-74389G was given intraperitoneally at two times as 5 mg/kg at 10 min prior to ischemia and at the beginning of reperfusion. Edema was determined by means of wet-dried weight method, and BBB of extravasation of Evans blue dye. Extravasation of Evans blue dye into brain following ischemia and reperfusion was 2.4-fold of control value and brought close to control levels by the effect of U-74389G (p<0.001). Post-ischemic reperfusion injury caused an increase of 3.7% in tissue water content of whole brain and administration of U-74389G lowered the cerebral edema (p<0.001). The loses in the Na(+)/K(+)-ATPase and Mg(2+)/Ca(2+)-ATPase activities occurred as 42.1% (p<0.01) and 65.7% (p<0.001) of control value, respectively. While Mg(2+)/Ca(2+)-ATPase activity was enhanced compared to vehicle-treated group of animals (p<0.01), Na(+)/K(+)-ATPase activity was fully recovered when compared to control by U-74389G (p>0.05). U-74389G also significantly attenuated neuronal necrosis (p<0.001) which was determined in the hippocampal CA1 subfield. Blood-brain barrier protection, attenuation of brain edema and neuronal necrosis concomitant with the stabilizing of membrane-bound enzymes brought about by the effect of U-74389G suggest that 21-aminosteroids are worthy of consideration in the acute treatment of cerebral ischemia.


Pathology & Oncology Research | 1999

Antiproliferative Properties of the Lazaroids U-83836E and U-74389G on Glioma Cells In Vitro

Ramazan Durmaz; Selda Deliorman; Serap Isiksoy; Ruhi Uyar; Kevser Erol; Esref Tel

The 21-aminosteroids (lazaroids) are a new family of steroid compounds that inhibit lipid peroxidation reactions. They are novel antioxidant agents, which have been shown to have antiproliferative properties on cancer cells and also are thought to prevent free radical-mediated blood-brain barrier damage. In order to understand the effect of lazaroids on glioma, we tested U-83836E and U-74389G at doses ranging between 0.1–100 μM on primary cultures of gliobiastoma multiforme from three patients, rat C6 glioma cell line, and 5th subculture established from one of the patients. The effects of both compounds on cell proliferation were determined using 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay U-83836E in the primary cultures was found to have 50% inhibitory concentrations (IC50) of 6.30, 6.75 and 6.50 μM, respectively. The IC50 value of U-74389G was calculated as 91 μM in only one of the patients. On C6 glioma cells, while the IC50 of U-83836E was 45 μM, U-74389G showed no cytotoxic effect. On the 5th subculture, U-83836E had an IC50 of 37.5 μM, but the cytotoxic effects of U-74389G was less than in that of the primary culture. In conclusion, these compounds were found to be more cytotoxic in primary culture than the cell lines and there were also differences between their members in the inhibition of cell survival.


Brain Research | 2011

Erythropoietin prevents nitric oxide and cathepsin-mediated neuronal death in focal brain ischemia.

Hilmi Ozden; Ramazan Durmaz; Güngör Kanbak; Kubilay Uzuner; Erinc Aral; Kazim Kartkaya; Sibel Canbaz Kabay; Metin Ant Atasoy

We examined the preventive effect of human recombinant erythropoietin (HrEPO) on nitric oxide (NO)-mediated toxicity to neurons and cysteine protease release into cytoplasm, which is attributed to neuronal death in brain ischemia. Focal cerebral ischemia was induced by permanent occlusion of middle cerebral artery in two sets of rat. The first set was used to monitor NO concentration and cathepsin activity, while the second was used for histological examination with hematoxylin and eosin, and TUNEL staining. A group in both set was administered human recombinant erythropoietin (HrEPO). NO content, cathepsins B and L activity increased significantly in the post-ischemic cerebral tissue (p<0.05). HrEPO treatment reduced NO concentration and cathepsin activity to control level (p>0.05). A significant increase in the number of necrotic and apoptotic neurons was observed in the post-ischemic cerebral cortex (p<0.05). HrEPO treatment was markedly lowered both of these (p<0.05). It is concluded that HrEPO prevents neuronal death by protecting neuronal liposomes from NO-mediated toxicity and suppressing the release of cathepsins.

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Metin Ant Atasoy

Eskişehir Osmangazi University

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Ali Arslantas

Eskişehir Osmangazi University

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Murat Vural

Eskişehir Osmangazi University

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Güngör Kanbak

Eskişehir Osmangazi University

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Sibel Canbaz Kabay

Imam Muhammad ibn Saud Islamic University

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Baki Adapinar

Eskişehir Osmangazi University

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Cengiz Bal

Eskişehir Osmangazi University

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Erhan Cosan

Eskişehir Osmangazi University

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Hilmi Ozden

Eskişehir Osmangazi University

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