Ferda Ozkan
Yeditepe University
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Featured researches published by Ferda Ozkan.
Urologic Oncology-seminars and Original Investigations | 2008
Mine Kucur; Ferruh K. Isman; Can Balcı; Bulent Onal; Munire Hacibekiroglu; Ferda Ozkan; Alper Ozkan
BACKGROUND YKL-40, also called human cartilage glycoprotein-39 (HC gp-39) and chitotriosidase are homologs of family 18 glycosyl hydrolases secreted by human macrophages. Although high levels of YKL-40 and chitotriosidase are associated with several diseases, the physiological functions of these enzymes are still unclear. YKL-40, a growth factor for connective tissue cells, a migration factor for endothelial and vascular smooth muscle cells, is expressed by several types of solid human carcinoma, including prostate carcinoma. PURPOSE The purpose of this study was to compare serum YKL-40 levels and chitotriosidase activity both in benign prostatic hyperplasia and primary prostate cancer. METHODS YKL-40 and chitotriosidase were determined in serum samples from 93 patients with primary prostate cancer and 61 patients with benign prostatic hyperplasia. Serum YKL-40 levels were measured by ELISA and chitotriosidase activity was determined by fluorometer. PSA levels were also measured by using an automated system. RESULTS Serum YKL-40 levels were significantly higher (P < 0.001) in patients with prostate cancer compared with control group whereas there was no significant difference between BPH and control group. Serum chitotriosidase activities were significantly higher in carcinoma patients with high Gleason score than the control group (P < 0.001). No significant difference was observed in BPH patients (P > 0.05). Both YKL-40 and chitotriosidase were found statistically significant higher in primary prostate cancer and BPH. CONCLUSION High serum YKL-40 levels in patients with primary prostate cancer indicate that YKL-40 may have a function in the progression of malignant diseases, whereas no significant elevation was observed in benign prostatic hyperplasia. Meanwhile, high serum chitotriosidase activity was observed only in patients with Gleason high grade, indicating possible macrophage involvement in cancer progression. Further studies are needed to elucidate the biologic role of YKL-40 in cancer aggressiveness and in progression of malignant diseases.
Bioscience, Biotechnology, and Biochemistry | 2013
Jale Çoban; Betül Evran; Ferda Ozkan; Aydın Çevik; Semra Doğru-Abbasoğlu; Müjdat Uysal
We investigated the effect of blueberries (BB) on lipids and oxidative stress parameters in hypercholesterolemic guinea pigs. The animals were fed for 75 d on a high-cholesterol (HC) diet supplemented with fresh BB. BB reduced oxidative stress and cholesterol accumulation in the aorta and liver of the guinea pigs. This effect may be related to its antioxidative potential and lipid-reducing effect.
Reproductive Biomedicine Online | 2015
Pınar Özcan; Cem Ficicioglu; Özge Kızılkale Yıldırım; Ferda Ozkan; Hatice Akkaya; Ismail Aslan
An increased accumulation of intracellular levels of reactive oxygen species with time may play an important role in the process of ageing. The antioxidant properties of resveratrol are dependent upon the up-regulation of endogenous cellular antioxidant systems. We evaluated whether resveratrol has protective antioxidant effects on ovarian damage related to oxidative stress in a rat model. Twenty-four female rats were randomly divided into three groups and were given saline (group 1: control); intraperitoneal cisplatin, 4.5 mg/kg, two weekly doses in total (group 2); or cisplatin, 4.5 mg/kg plus intraperitoneal resveratrol 10 mg/kg/day, 24 h before the administration of cisplatin (group 3). Serum anti-Müllerian hormone (AMH) concentrations were significantly lower in group 2 than in group 3 (P < 0.01 and P = 0.04, respectively). The evaluation of the atretic and antral follicle counts revealed statistically significant differences between the groups (P = 0.04 and P < 0.01, respectively). A statistically significant difference was observed in the follicle count positive for AMH between the groups (P = 0.01). Oxidative stress plays an important role in the process of ovarian ageing. Because of its natural antioxidant properties, resveratrol may be an effective option in protecting ovarian tissue against oxidative damage.
Journal of Clinical Neuroscience | 2008
Merih Is; Nil Çomunoğlu; Cem Comunoglu; Bülent Eren; Isin Dogan Ekici; Ferda Ozkan
The human brain is uniquely powerful in its cognitive abilities, yet the hippocampal and neocortical circuits that mediate these complex functions are highly vulnerable during aging. In this study, we analyzed age-related changes in the rat hippocampus by studying newborn (1 month), middle-aged (12 months), and older (24 months) male and female Sprague-Dawley rats. We evaluated neuronal dystrophy, neuron scattering, and granulovacuolar degeneration in the hippocampal area using light microscopy, according to age and gender. We detected significant neuronal dystrophy in the CA1, CA2, and CA3 areas in male rats, and in the CA1, CA3, and CA4 areas in female rats. Degenerative changes, indicated by neuron scattering, were observed in the CA1, CA2, and CA3 areas of male and the CA2 and CA4 areas of female rats. Changes in all areas of the hippocampus were observed with increasing age; these changes included neuronal dystrophy and neuron scattering and did not differ significantly between male and female rats.
Apmis | 2007
Nil Çomunoğlu; Haydar Durak; Cem Çomunoğlu; A. Işin Doğan Ekici; Ferda Ozkan; Elif Ulker Akyildiz; Şennur İlvan; Zerrin Calay; Nil Molinas
We examined the expression pattern of cyclooxygenase‐2 (COX‐2) and c‐kit in uterine smooth muscle neoplasms and tried to determine the role of these markers in differential diagnosis. Archival tissue from 64 patients with uterine smooth muscle neoplasms (20 leiomyomas (LMs), 22 atypical leiomyomas (ALMs), and 22 leiomyosarcomas (LMSs)) was immunostained with antibodies against estrogen (ER) and progesterone receptors (PR), COX‐2 and c‐kit. 7 of 20 LM cases and 5 of 22 ALM cases were immunopositive for COX‐2, whereas none of the LMS cases stained immunopositive (p≤0.05). 4 of 20 LM cases and 5 of 22 ALM cases were immunopositive for c‐kit, whereas 15 of 22 LMS cases showed c‐kit immunopositivity (p≤0.05). In conclusion, very few LMs and ALMs show COX‐2 immunopositivity. LMSs usually do not express COX‐2. COX‐2 expression in smooth muscle tumors is not a prominent feature. Therefore, COX‐2 inhibitors may not be useful in LMS therapy. C‐kit was significantly expressed in uterine LMSs.
Journal of Clinical Virology | 2013
Meltem Ugras; Ayça Vitrinel; Gulden Yilmaz; Kenan Midilli; Ferda Ozkan
The varicella zoster virus (VZV) is a very rare cause of gastritis. Gastritis caused by VZV can be presented as abdominal pain, vomiting. Most of the cases reported with varicella gastritis in the literature are immunocompromised patients with various kinds of malignancy, and most of these patients are adults. Here we report an adolescent girl with acute abdominal pain. The girl was immunocompetent. Her endoscopically taken biopsy material revealed varicella, and her gastritis was healed with acyclovir therapy. This is a very rare condition and not frequently reported in the literature. The authors want to drive attention to the fact that varicella gastritis can be seen in immunocompetent children, the presentation can be nausea, vomiting and/or (severe) abdominal pain. Serological studies may be less helpful than tissue studies, so interventional procedures should be done.
Journal of The Turkish German Gynecological Association | 2013
Nilüfer Çetinkaya Kocadal; Rukset Attar; Gazi Yildirim; Cem Fıçıcıoğlu; Ferda Ozkan; Bayram Yilmaz; Narter Yesildaglar
OBJECTIVE We aimed to determine the effects of melatonin treatment on endometrial implants in an oopherectomized rat endometriosis model. MATERIAL AND METHODS This study is a prospective, randomised, controlled experimental study. It was carried out at the Experimental Research Center of Yeditepe University (YUDETAM). Twenty-two, female, non-pregnant, nulligravid Spraque-Dawley albino rats were included in our study. Endometriosis was surgically induced in oopherectomized rats. Rats were randomised into two groups: control group and melatonin group. In the melatonin group, rats were treated with melatonin (20 mg/kg/day) for two weeks. After the operations were performed to assess the regression of the endometriotic lesions, melatonin treatment was stopped. At the end of the sixth week necropsies were performed to assess the rate of recurrence. The volume and histopathological scores of endometriotic foci were examined. RESULTS Volumes of the endometriotic lesions significantly decreased in the melatonin group. Also, when the melatonin group was analysed within itself, endometriotic lesion volumes decreased and histopathological scores increased significantly. CONCLUSION Melatonin causes regression of the endometriotic lesions in rats and improvement in their histopathological scores.
Case reports in gastrointestinal medicine | 2011
Murat Kalayci; Ümit Akyüz; Alp Demirag; Bengi Gurses; Ferda Ozkan; Özcan Gökçe
Introduction. Schwannomas are quiet rare in the retroperitoneal region. Here, we describe an incidentally detected retroperitoneal schwannoma in the abdominal computerized tomography (CT) of a patient with acute appendicitis. Case Presentation. A 38-year-old woman was admitted to the emergency service with the complaints of progressive abdominal pain and nausea for the last 24 hours. Abdominal examination was compatible with acute abdomen. Acute appendicitis was diagnosed by CT. During CT evaluation, a round shaped soft-tissue mass at the retroperitoneal area inferior to the right kidney was detected, The mass was resected and histology revealed schwannoma. Conclusion. Rare tumoral lesions with benign course such as schwannoma can be detected incidentally.
Journal of International Medical Research | 2007
Fk Isman; Mine Kucur; B Baysal; Ferda Ozkan
Following major tissue injury, hyaluronic acid production increases as a rapid response survival mechanism. Increased hyaluronic acid production and turnover are often associated with increased hyaluronidase activity, the enzyme that degrades hyaluronic acid. We investigated whether hyaluronic acid and hyaluronidase can be used as non-invasive markers of acute disease activity in hepatitis C by studying 26 patients with acute hepatitis C, 89 with chronic hepatitis C and 32 healthy controls. Chronic hepatitis C subjects were classified into five subgroups according to the stage of liver fibrosis. Serum aspartate aminotransferase and alanine aminotransferase activities and hyaluronic acid levels were increased in hepatitis C patients compared with the controls. Serum hyaluronic acid elevation correlated with disease progression. Serum hyaluronidase activities were also increased in patients compared with the controls, but decreased with disease progression. We conclude that both hyaluronidase and hyaluronic acid may be useful as early non-invasive serum indicators of disease activity in acute hepatitis C.
Apmis | 2006
Ferda Ozkan; Remziye Bilgic; Suna Cesur
A keratoacanthoma of the vulva in a 33‐year‐old woman is described. The patient presented with a rapidly growing exophytic lesion of 1 cm in diameter over the clitoris that had been present for a couple of months. An excisional biopsy was performed. Pathologic examination of the exophytic nodule showed squamous proliferation with a characteristic central keratin‐ filled crater. There were pushing margins. High power microscopy showed squamous cells of cytologically bland appearance with glassy cytoplasm. There were few mitotic figures. Less than 10% Ki‐67‐positive staining nuclei were seen. There was no p53 oncoprotein overexpression. Keratoacanthoma of the vulva is rare with only five cases having been reviewed in the English literature since 1985. Keratoacanthomas are rapidly growing crateriform lesions on the sun‐exposed skin of the elderly. Because of its rarity in the vulva, the lesion can be misinterpreted as a malignant lesion such as squamous cell carcinoma. Awareness of vulvar occurrence of keratoacanthoma and its characteristic histopathologic features will help avoid misdiagnosis of a squamous cell carcinoma leading to radical surgery.