PubMed Health⌕ Search

Biomedical subjects

Ozlem Ozen

Publications and source records attributed to Ozlem Ozen.

12 recordsLinked to original sources
PubMed2006

Impact of aromatase inhibitors on adhesion formation in a rat model.

OBJECTIVE: To investigate the antiadhesion potential of tamoxifen and anastrozole in a rat uterine horn model. DESIGN: Experimental animal study. SETTING: University animal laboratory. ANIMAL(S): Forty-five female Wistar albino rats. INTERVENTION(S): We examined the effects of tamoxifen and anastrozole to reduce the extent and severity of postoperative adhesions in a rat uterine horn model: the control group received no therapy while the second and third groups received 500 mug/day tamoxifen and 0.2 mg/kg/day anastrazole, respectively, through an enteric tube, starting 5 days before surgery. These protocols were continued for 14 days after the surgery until the rats were killed. MAIN OUTCOME MEASURE(S): Adhesions were scored according to their extent and severity, and specimens were also evaluated and scored histologically according to the following features: inflammation, fibroblastic activities, foreign body reaction, collagen formation, and vascular proliferation. RESULT(S): Anastrozole had the lowest mean adhesion scores, and these scores were significantly different from those of the controls. However, there were no statistically significant differences between control and tamoxifen groups and between tamoxifen and anastrozole groups. Histologic scores were lowest in the anastrozole group, which were statistically different from those of the tamoxifen and anastrozole groups, whereas scores of the control group were not statistically different from those of the tamoxifen group. CONCLUSION(S): Anastrazole decreased postsurgical adhesion scores by both visual scores and histologic analyses in a rat model. Further experimental and clinical trials are required to confirm these results.

Anastrozole↗
PubMed2006

A novel technique for vas deferens transection repairs.

The purpose of this study is to describe a technique, that is as successful as microsurgery in terms of patency rates and histopathologic assessments, and can be performed even by untrained hands in microsurgery, for repairing vas deferens injuries that can be perceived during inguinal herniorrhaphy. Thirty male Wistar-Albino rats were randomly allocated to five groups. In control group, the vas deferens was harvested without any surgical intervention (Group 1) and in sham group the vas was harvested after a limited dissection (Group 2). Three suture approximation technique was carried out in Group 3, and a novel vasovasostomy technique was carried out by using a hypodermal needle in Groups 4 and 5, with polypropylene and polyglactin 910 (rapid vicryl), respectively. Results were evaluated in terms of operative time, patency and flow rates, inflammation and sperm granuloma. The mean operative times for hypodermal needle assisted approximation of Groups 4 and 5 were found significantly less than Group 3. The compared results of the groups in terms of patency, flow rate, inflammation and spermatic granuloma indicated Group 4 to be superior to the other groups. We have found the hypodermal needle assisted approximation technique to be easier, less time consuming and cost effective. With these promising results, this modus operandi can be described as an appropriate technique for vas deferens transection repairs.

Animals↗
PubMed2006

Pretreatment with simvastatin reduces lung injury related to intestinal ischemia-reperfusion in rats.

In this rat model study we evaluated whether pretreatment with simvastatin affects the severity of acute lung injury caused by intestinal ischemia-reperfusion (I/R). Twenty-four animals were randomly allocated to three equal groups (sham, control, simvastatin). The simvastatin group was pretreated with simvastatin 10 mg x kg(-1) x day(-1) for 3 days, whereas the other groups received placebo. The simvastatin and control groups underwent 60 min of superior mesenteric artery occlusion and 90 min of reperfusion. Compared with the simvastatin group, the control group exhibited significantly more severe intestinal I/R-induced acute lung injury, as indicated by lower Pao2 and oxygen saturation (P = 0.01 and P = 0.005, respectively) and higher mean values for neutrophil infiltration of the lungs (P = 0.003), total lung histopathologic injury score (P = 0.003), lung wet-to-dry weight ratio (P = 0.009), and lung-tissue malondialdehyde levels (P = 0.016). The control and simvastatin groups had similar serum levels and similar bronchoalveolar lavage fluid levels of cytokines (interleukin-1, interleukin-6, and tumor necrosis factor-alpha) and P-selectin at all measurements, except for a significantly higher level of bronchoalveolar lavage fluid P-selectin in the control group (P = 0.006). Pretreatment with simvastatin reduces the severity of acute lung injury induced by intestinal I/R in rats.

Animals↗
PubMed2006

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

OBJECTIVE: One 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. METHODS: Twenty-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. RESULTS: Basilar 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 microm; P = 0.039) and the SAH group (2142 +/- 195 microm; 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). CONCLUSION: The 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.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed2005

Chromosome 1p36 and 22qter deletions in paraffin block sections of intracranial meningiomas.

Meningiomas are the most frequent benign tumors of the intracranial cavity. The classification and underlying pathogenetic mechanisms have been reported to be investigated by both pathological and genetic methods. In this study, we aimed to detect 1p36 and 22qter deletions by fluorescence in situ hybridization (FISH) in archival materials of 50 intracranial meningioma patients. The clinical material consisted of paraffin-embedded tissue sections from 50 patients who were surgically treated and had histopathologic diagnosis of an intracranial meningioma. We observed 1p36 deletion in 23/50 (46%) and 22qter deletion in 33/50 (66%) patients. In addition, we observed 22qter deletion in 26/36 (72.2%) patients with meningothelial meningioma. This finding implies that 22qter deletion might play an important role in the pathogenesis of meningothelial meningioma. On the other hand, no alterations were documented in the frequency of these chromosomal alterations according to the grade of meningiomas, suggesting that malignant progression of these tumors depends on other, more relevant, genetic changes.

Adult↗
PubMed2005

Mucinous cystadenocarcinoma of a minor salivary gland in the upper lip: case report.

Mucinous cystadenocarcinoma of the salivary gland is a rare entity that has only recently been described. This lesion was included in the 1991 World Health Organization Classification as "papillary cystadenocarcinoma," and that same year the United States Armed Forces Institute of Pathology classified it as "cystadenocarcinoma with or without a papillary component." Only a small proportion of salivary gland tumors are adenocarcinomas. Most mucinous cystadenocarcinomas affect the major salivary glands, particularly the parotid. These are low-grade malignancies, and most that occur in the minor salivary glands show very little aggressive behavior. These tumors are histologically similar to adenocarcinomas of the gastrointestinal tract. It is often difficult to differentiate them from other neoplasms. The differential diagnosis includes mucoepidermoid carcinoma, acinic cell carcinoma, salivary duct carcinoma, nasal adenocarcinoma, and metastatic carcinoma. This report describes the case of an 80-year-old man who presented with a painless swelling in his right upper lip that had been present for 1 month. Fine-needle aspiration biopsy of the lesion revealed inflammatory cells without an epithelial component. The treatment was wide excision, and there was no recurrence during 6 months of follow-up. The pathological diagnosis was low-grade mucinous cystadenocarcinoma of a minor salivary gland.

Aged, 80 and over↗
PubMed2005

Effect of melatonin on cerebral vasospasm following experimental subarachnoid hemorrhage.

OBJECT: The current study was undertaken to determine whether melatonin therapy reverses vasospasm and prevents apoptosis by inhibiting lipid peroxidation in an experimental subarachnoid hemorrhage (SAH) model. MATERIALS AND METHODS: The rabbits were divided into four groups as follows: Group 1, SAH + melatonin (5 mg/kg/i.p. BID) simultaneously with SAH (n = 6); Group 2, SAH + melatonin (5 mg/kg/i.p. BID) treated 2 hours after SAH (n = 6); Group 3, control group (n = 4); Group 4, SAH only (n = 6). Light microscopic examinations of the basilar arteries were performed to demonstrate the pathophysiological changes of the arterial wall with hematoxylin- eosin. Apoptosis: Immunohistology using the ApopTag Peroxidase In Situ Apoptosis Detection Kit was used to demonstrate apoptosis in a cross section of basilary arteries. Apoptotic index was calculated as the number of the immunoreactive nuclei per total number of endothelial cells, and expressed as a percentage. RESULTS: The results of measurements of diameters of the vessels between groups were significantly different (p = 0.028). While basilar arteries of the SAH only group showed 57% constriction, Groups 1 and 2 were calculated as 33 and 26% constriction, respectively, compared with the control group (p < 0.05). And also Groups 1 and 2 showed significant protection of apoptosis compared with Group 4. The difference between the four groups was tested by Kruskal-Wallis test and the significance between the two groups was tested by Mann- Whitney U-test. CONCLUSION: Melatonin with its strong antioxidant effect can prevent SAH-induced vasospasm and apoptosis of endothelial cells of vessels.

Animals↗
PubMed2005

Remote cerebellar hemorrhage after a spinal surgery complicated by dural tear: case report and literature review.

OBJECTIVE AND IMPORTANCE: This report presents a case in which cerebellar hemorrhage occurred after lumbar decompression surgery that was complicated by dural tear and prolonged cerebrospinal fluid leakage. Remote cerebellar hemorrhage after spinal surgery is extremely rare. Our objective is to describe this unusual complication, discuss the possible mechanisms of remote cerebellar hemorrhage, and review the literature. CLINICAL PRESENTATION: A 73-year-old woman underwent surgery for lumbar spinal stenosis. A dural tear occurred during decompression, and the patient developed remote cerebellar hemorrhage on postoperative Day 2. INTERVENTION: The cerebellar hemorrhage was treated surgically, and a biopsy of hemorrhagic brain parenchyma revealed an arteriovenous malformation. CONCLUSION: Although it is an extremely rare complication, remote cerebellar hemorrhage should be kept in mind as a possible complication of spinal surgery, especially in operations complicated by dural tears.

Aged↗
PubMed2004

Expression of matrix metalloproteinases and their inhibitors in medulloblastomas and their prognostic relevance.

PURPOSE AND EXPERIMENTAL DESIGN: The cellular mechanisms leading to metastatic disease in medulloblastoma (MB), the most common malignant brain tumor in childhood, are mainly unknown. Recently, however, the involvement of matrix metalloproteinases (MMPs) has been suggested. We examined the expression and localization of four MMPs-MMP-2 and -9, membrane-type 1 and 2 MMP (MT1- and MT2-MMP)-and correlated the data with those for their main inhibitors, tissue inhibitors of metalloproteinases (TIMP-1, -2, and -3), in 83 classical and 18 desmoplastic MBs. RESULTS: Independent of the histological subtype, MMP-2 expression was found in a small percentage of tumors, whereas MMP-9 and MT1- or MT2-MMP were expressed in >75% of tumor samples. The expression of TIMP-1, -2, and -3, on the other hand, was found to depend on the histological subtype: TIMP-3 was often found in classical MB, whereas TIMP-2 was often expressed in desmoplastic MB (P = 0.007-0.001). In addition, both TIMP-3 and -2 correlated significantly with the expression of all studied metalloproteinases except MMP-2. TIMP-1, detected only in classical MB in a low percentage, was the only TIMP that correlated with the expression of MMP-2. Kaplan-Meier estimation revealed significantly reduced long-term survival of patients with strong MMP expression in tumor samples. In multivariate logistic regression analysis, however, the prognosis was significantly determined only by clinical parameters. CONCLUSIONS: TIMP-3 and -2 expression is highly correlated with histological subtypes of MBs and strongly associated with the expression of certain MMPs. The expression of TIMPs and MMPs, however, does not determine prognosis independently of clinical parameters.

Adolescent↗
PubMed2004

Chordoid meningioma: rare variant of meningioma.

Chordoid meningioma is a rare variant of meningioma that bears a striking histological resemblance to chordoma and has greater likelihood of recurrence. Although most meningiomas occur in the intracranial, orbital and intravertebral cavities, rare meningiomas have been reported in extracranial organs; thus, it is important to be able to distinguish them from other neoplasms that have similar histology but different biological behavior and therapies. A case of chordoid meningioma in a 48-year-old woman who did not have Castleman's syndrome is described in the present report. The patient presented with a mass in her left frontoparietal region, and had been suffering from headaches for many years. Magnetic resonance imaging of the brain demonstrated an expansive lytic lesion in the squamous portion of the left temporal bone. The lesion extended in both directions. Histological examination of the surgical specimen revealed a tumor composed of cords and nests of eosinophilic vacuolated cells embedded in a myxoid matrix. A typical meningiomatous pattern was observed focally, and positive staining of the tumor cells for vimentin and epithelial membrane antigen confirmed the diagnosis of chordoid meningioma.

Choroid Plexus Neoplasms↗