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Featured researches published by Bülent Celasun.


Brain Research | 2002

Magnesium pre-treatment reduces neuronal apoptosis in newborn rats in hypoxia–ischemia

Canan Turkyilmaz; Zafer Türkyılmaz; Yıldız Atalay; Figen Soylemezoglu; Bülent Celasun

Hypoxic-ischemic brain damage has significant mortality and morbidity in newborns. Although the role of magnesium in neonatal hypoxic-ischemic brain injury related to N-methyl-D-aspartate receptors has been widely studied; the effects of magnesium on neuronal apoptosis have not been known exactly in hypoxia-ischemia. The aim of this study was to investigate the effects of magnesium on neuronal apoptosis in the 7-day-old rat hypoxia-ischemia model. Seven-day-old rats were administered magnesium sulfate (group 1; n=9) or saline (group 2; n=9) intraperitoneally before hypoxia-ischemia. Additionally 18 seven-day-old rats were given magnesium sulfate (group 3; n=9) or saline (group 4; n=9) after hypoxic-ischemic insult. Neuronal apoptosis was investigated by the dUDP-biotin nick end-labeling (TUNEL) method following 3-day recovery in all subjects. In evaluating TUNEL-positive cells, we firstly calculated the areas (mm(2)) of brain regions, hippocampus, striatum, cortex, in right and left hemispheres in subjects by IMAGE analysis. The numerical density was calculated as the number of cells per square millimeter by counting all TUNEL-positive cells. Afterwards, the ratio of right side numeric density to sum of right and left side numeric densities (right Apoptosis Index) was calculated for every brain region in rats receiving magnesium and compared to vehicle groups. The right Apoptosis Index of the hippocampus in magnesium pre-treated rats (mean+/-S.D.; 36.6+/-22.1) was significantly lower than vehicle (61.0+/-16.0; P<0.05); whereas right apoptosis indices were not changed by magnesium pre-treatment in striatum and cortex. Additionally, magnesium sulfate administration following hypoxic-ischemic insult also had no effect on right apoptosis indices in all three brain regions. It is concluded that magnesium might have a role in preventing neuronal apoptosis due to neonatal hypoxic-ischemic brain injury.


Journal of Laryngology and Otology | 1994

Solitary fibrous tumour arising from sublingual gland: report of a case

Ömer Günhan; F. Rüstü Yildiz; Bülent Celasun; Turgut Ünder; Rifki Finci

A solitary fibrous tumour is a pleural tumour which may rarely be detected at non-pleural sites. In this report, the case of a solitary fibrous tumour arising from the sublingual salivary gland is described.


International Urogynecology Journal | 2005

Smooth muscle fraction of the round ligament in women with pelvic organ prolapse: a computer-based morphometric analysis

Ozlem Ozdegirmenci; Yildirim Karslioglu; Suat Dede; Sinan Karadeniz; Ali Haberal; Ömer Günhan; Bülent Celasun

Our objective was to compare the collagen and muscle content of the round ligament of uteri in women with pelvic organ prolapse. We evaluated the tissue samples obtained from the round ligaments of 22 patients with uterine prolapse who underwent vaginal hysterectomy (group A, study) and from 26 patients with no pelvic relaxation in whom total abdominal hysterectomy was performed for benign reasons (group B, controls). Morphometric analysis was performed on histologic cross-sections of the round ligament. Sections from each sample were stained with hematoxylin and eosin and Masson’s trichrome methods. A computer system was used for morphometric measurements. We used independent samples t-test or Mann-Whitney U test to investigate the difference between the two groups. It was found that the smooth muscle fraction of the round ligament in women with uterine prolapse was significantly decreased compared with that of healthy control subjects and concluded that decreased smooth muscle content may be an important pathogenetic factor in uterine prolapse.


Diagnostic Microbiology and Infectious Disease | 2002

The evaluation of diagnostic methods for the detection of Helicobacter pylori in gastric biopsy specimens

Ozgul Kisa; Ali Albay; Mehmet Refik Mas; Bülent Celasun; Levent Doganci

PCR is a rapid, sensitive and accurate method for the specific detection of Helicobacter pylori from gastric biopsy specimens. In our study, 104 gastric tissue specimens from symptomatic adult patients were examined by staining, culture, PCR and nested PCR methods for detection of H. pylori. According to our results, positivity was achieved in 24% (25/104) with Giemsa staining, 34% (36/104) with histopathology, 36% (38/104) with PCR and 41% (43/104) with nested PCR respectively, whereas H. pylori was isolated in only 33% (35/104) of the cultures on the biopsy specimens. Both the sensitivity and the positive predictive value of the nested PCR method were 100%, and both the specificity and negative predictive value were 98%. As a conclusion, our results suggest the nested PCR as a highly valuable method in the detection of H. pylori with a reasonably high sensitivity and specificity.


Neurosurgery | 2002

Cerebellar aspergillosis: case report and literature review.

Ersin Erdogan; Murat Beyzadeoglu; Fikret Arpaci; Bülent Celasun

OBJECTIVE AND IMPORTANCE An unusual, but not unique, case of cerebellar aspergillosis associated with autologous peripheral blood stem cell transplantation for breast cancer is presented. CLINICAL PRESENTATION A 45-year-old woman with breast cancer underwent chemotherapy and radiotherapy as well as autologous peripheral blood stem cell transplantation. She developed a cerebellar aspergillosis abscess that was treated successfully with two surgical resections. INTERVENTION After removal of pus and the abscess wall, the patient received local application of amphotericin B (AmB). She received AmB 1 mg/kg/d for 3 months and itraconazole 100 mg/kg/d for 1 year. After 3 months of AmB treatment, magnetic resonance imaging revealed that disease had not recurred. CONCLUSION In cases of central nervous system aspergillosis, to increase the therapeutic efficiency, AmB can also be applied to the abscess cavity. Computed tomographic and contrast-enhanced magnetic resonance imaging scans play an important role in establishing early diagnosis in high-risk, immunocompromised patients.


Neurosurgery | 2006

Systemic administration of phosphodiesterase V inhibitor, sildenafil citrate, for attenuation of cerebral vasospasm after experimental subarachnoid hemorrhage.

Basar Atalay; Hakan Caner; Melih Cekinmez; Ozlem Ozen; Bülent Celasun; Nur Altinors

OBJECTIVEOne of the phosphodiesterase isoenzymes, Type V (PDE V), specifically hydrolyzes cyclic guanosine monophosphate to cause vasoconstriction. This study analyses the effect of PDE V inhibition with sildenafil citrate (SC) on cerebral vasospasm and its effect on apoptotic changes of the vascular endothelium. METHODSTwenty-four rabbits were divided into four groups. The first group was composed of sham-surgery animals. The second group was the subarachnoid hemorrhage (SAH) group, in which cerebral vasospasm was induced. In the third group, sham-surgery rabbits were treated with SC. In the fourth group, animals were treated with SC after SAH. SC was administered for 48 hours, 0.7 mg/kg, three times per day in Groups 3 and 4. Basilar artery lumen circumferences were measured in all groups by computerized image analysis. The terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) method was used to evaluate the rate of apoptosis between SAH and SC-treated SAH groups. Results were compared by analysis of variance and paired t tests, and P values less than 0.05 were considered significant. RESULTSBasilar artery circumferences between groups were significantly different(P < 0.001). SC (0.7 mg/kg, three times per d) significantly dilated the basilar arteries in both the sham-surgery group (2370 ± 233 μm; P = 0.039) and the SAH group(2142 ± 195 μm; P = 0.006) after 48 hours of treatment. The TUNEL method for apoptosis revealed that actual numbers of the apoptotic endothelial cells per cross section after SAH in the control (no treatment) (73 ± 2) and SC-treated (0.7 mg/kg) groups(76 ± 3) were not significantly different (P > 0.05). CONCLUSIONThe vasodilatory effect of SC was observed to be significant on normal cerebral vessels and after SAH-induced vasospasm. SC did not prevent apoptosis of the endothelium in our study, which suggests that prevention of apoptosis is not necessary in the treatment of cerebral vasospasm.


Journal of Child Neurology | 2005

Protective Effects of Valproic Acid Against Hypoxic-Ischemic Brain Injury in Neonatal Rats

Nimet Kabakus; Ilknur Ay; Figen Soylemezoglu; Ayhan Ozcan; Bülent Celasun

Although controversial, protective and therapeutic effects of valproic acid in various types of cellular injury suggest a potential role for this agent in hypoxic-ischemic brain injury. We therefore investigated the effects of valproic acid in an experimental model of neonatal hypoxic-ischemic brain injury. To examine the effect of valproic acid in this condition, hypoxic-ischemic brain injury was induced in 7-day-old rat pups by ligation of the right common carotid and then the pups were exposed to 1 hour of hypoxia in 8% oxygen. Low (200 mg/kg/day) and high (400 mg/kg/day) doses of valproic acid were administered in a 5-day regimen. Neuropathologic evaluation was performed using the hippocampus, cerebral cortex, and basal ganglia in the coronal plane. The 5-day regimen of valproic acid administration resulted in some protective and therapeutic effects on the brain damage and neuronal apoptosis in both hemispheres in a dose-dependent manner. Administration of valproic acid also decreased the percentage of apoptotic neurons in the contralateral hemisphere (P < .05). These results suggest that valproic acid can have therapeutic and protective effects in hypoxic-ischemic brain injury. (J Child Neurol 2005;20:582—587).


Journal of Oral and Maxillofacial Surgery | 1989

Epithelial odontogenic ghost cell tumor: report of a case.

Ömer Günhan; Onur Şengün; Bülent Celasun

Kyste odontogene calcifiant du maxillaire inferieur chez un homme de 72 ans. Discussion de la nosologie


Neuropathology | 2005

Desmoplastic non-infantile ganglioglioma.

Onder Onguru; Bülent Celasun; Ömer Günhan

Desmoplastic ganglioglioma is a rare, markedly desmoplastic variant of ganglioglioma that usually presents in the first year of life. It is a mixed glial and neuronal cerebral tumor. A few cases of desmoplastic ganglioglioma have been  reported  in  non‐infantile  patients.  We  report  a  case of desmoplastic ganglioglioma in a 14‐year‐old boy. The patient presented with a large solid cystic mass with mild peritumoral edema in the right posterior parieto‐occipital region with direct contact to the falx cerebri. Histopathological examination revealed a low‐grade glial tumor with prominent desmoplasia including hypocellular collagenous areas. The tumor was well demarcated with respect to the surrounding brain. Ganglion cells with dysplastic features were present in the tumor and clustered in some areas. Focal lymphocytic infiltration was also observed. Mitotic activity was very low. Immunohistochemistry revealed glial fibrillary acidic protein positivity in the astrocytic cells hidden in the desmoplastic tissue. Synaptophysin and neuron specific enolase were positive in ganglion‐like neuronal cells. The MIB‐1 labeling index was less than 1%. This present case confirms that desmoplastic ganglioglioma can be present in young adult patients with its characteristic radiologic features.


Acta Neuropathologica | 2006

The distribution pattern of pathology and cholinergic deficits in amygdaloid complex in Alzheimer's disease and dementia with Lewy bodies

Huseyin Sahin; Murat Emre; Iryna Ziabreva; Elaine K. Perry; Bülent Celasun; Robert H. Perry

We studied the distribution pattern of pathology and cholinergic deficits in the subnuclei of the amygdaloid complex (AC) in five patients with Alzheimers disease (AD), eight with dementia with Lewy bodies (DLB) and five normal controls. In controls, the basal nucleus contained the highest choline acetyltransferase activity; the activity in the lateral and central nuclei and those in the cortical, medial and accessory basal nuclei were comparable. In AD, there was a significant decrease in choline acetyltransferase activity in the accessory basal and lateral nuclei, in DLB a significant decrease was observed in the accessory basal, lateral and cortical nuclei. Compared to controls the hyperphosphorylated tau-pathology burden was significantly higher in the basal, central and medial nuclei in AD and in the central, cortical, lateral and medial nuclei in DLB. The amyloid plaque burden was significantly higher in the accessory basal, basal, lateral and cortical nuclei in AD and in all nuclei in DLB. The α-synuclein burden was significantly higher in all nuclei in both AD and DLB. Compared to AD α-synuclein burden was higher in all nuclei in DLB. There were no correlations between the distribution pattern of hyperphosphorylated tau-pathology, amyloid plaques and α-synuclein-positive structures, and choline acetyltransferase activity, except the lateral nucleus in DLB. In conclusion we found no relationship between the pattern of cholinergic deficits and the distribution pattern of lesions in the AC of patients with AD or DLB. Cholinergic deficits were more prominent in the nuclei of basolateral (BL) group in AD, whereas the nuclei of both BL and corticomedial groups were involved in DLB, which may be due to the involvement of both basal forebrain and brainstem cholinergic nuclei in the latter.

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Ömer Günhan

Military Medical Academy

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Rifki Finci

Military Medical Academy

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Onder Onguru

Military Medical Academy

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Ayhan Ozcan

Military Medical Academy

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Harun Tuğcu

Military Medical Academy

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