Gamze Yurdakan
Zonguldak Karaelmas University
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Featured researches published by Gamze Yurdakan.
Diagnostic Pathology | 2012
Banu Dogan Gun; Burak Bahadir; Sibel Bektas; Figen Barut; Gamze Yurdakan; Nilufer Onak Kandemir; Sukru Oguz Ozdamar
BackgroundFascin and CD44v6 may have significant roles as biomarkers in tumour progression and metastasis. In endometrioid carcinomas, the fascin expression profile is less defined, and the significance of CD44v6 is uncertain. We aimed to investigate the expressions of both fascin and CD44v6 in endometrioid carcinomas and to evaluate their inter-relation with clinicopathological parameters.MethodsFascin and CD44v6 expressions were evaluated, individually and in combination, in a series of 47 endometrioid carcinomas and 10 proliferative endometrium samples. The staining extent and intensity of both markers in tumour cells were scored semiquantitatively. The relationship between immunoexpressions and clinicopathological variables was assessed.ResultsThe expression rates of fascin and CD44v6 in endometrioid carcinoma were 72.34% and 46.80%, respectively. Although these expression rates were higher than those in proliferative endometrial samples, fascin expression showed a statistically significant difference from the normal group (p = 0.02), but CD44v6 did not differ (p = 0.54). Fascin expression was significantly correlated with tumour grade (p = 0.003) and neural invasion (p = 0.036) in a univariate analysis. In contrast, no significant correlation was found between CD44v6 and any of the clinicopathological parameters.ConclusionsOur findings suggest that fascin might be an independent prognostic indicator in the different steps of extracellular matrix invasion. On the other hand, CD44v6 was not a predictive factor in endometrioid cancer.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8511594927206899.
Journal of Surgical Research | 2012
Volkan Hancı; Gamze Yurdakan; Serhan Yurtlu; Işıl Özkoçak Turan; Emine Yılmaz Sipahi
BACKGROUND We assessed the effects of dexmedetomidine in a rat model of α-naphthylthiourea (ANTU)-induced acute lung injury. METHODS Forty Wistar Albino male rats weighing 200-240 g were divided into 5 groups (n = 8 each), including a control group. Thus, there were one ANTU group and three dexmedetomidine groups (10-, 50-, and 100-μg/kg treatment groups), plus a control group. The control group provided the normal base values. The rats in the ANTU group were given 10 mg/kg of ANTU intraperitoneally and the three treatment groups received 10, 50, or 100 μg/kg of dexmedetomidine intraperitoneally 30 min before ANTU application. The rat body weight (BW), pleural effusion (PE), and lung weight (LW) of each group were measured 4 h after ANTU administration. The histopathologic changes were evaluated using hematoxylin-eosin staining. RESULTS The mean PE, LW, LW/BW, and PE/BW measurements in the ANTU group were significantly greater than in the control groups and all dexmedetomidine treatment groups (P < 0.05). There were also significant decreases in the mean PE, LW, LW/BW and PE/BW values in the dexmedetomidine 50-μg/kg group compared with those in the ANTU group (P < 0.01). The inflammation, hemorrhage, and edema scores in the ANTU group were significantly greater than those in the control or dexmedetomidine 50-μg/kg group (P < 0.01). CONCLUSION Dexmedetomidine treatment has demonstrated a potential benefit by preventing ANTU-induced acute lung injury in an experimental rat model. Dexmedetomidine could have a potential protective effect on acute lung injury in intensive care patients.
Acta Obstetricia et Gynecologica Scandinavica | 2008
Gamze Yurdakan; Tulu Emre Ekem; Burak Bahadir; Banu Dogan Gun; Gamze Mocan Kuzey; Sukru Oguz Ozdamar
Background. Early placental development is associated with complex regulatory mechanisms, and molecular communication problems that arise during the developmental process are dangerous for continuation of the pregnancy. As studies on the process of invasion and migration of trophoblast cells have shown the importance of cell–cell and cell–matrix interactions, we examined the effects of adhesion molecules on the mechanism(s) of spontaneous abortions and compared them to elective abortion materials using histopathological and immunohistochemical methods. To the best of our knowledge, this is the first study to investigate adhesion molecules in spontaneous abortions. Methods. Curettage materials from abortions were examined retrospectively in the Department of Pathology, Zonguldak Karaelmas University School of Medicine, Zonguldak, Turkey. CD31/PECAM‐1 (endothelial cell marker), CD44v (variant 3), E‐cadherin, CD54/ICAM‐1, and CD106/VCAM‐1 expression profiles were evaluated by immunohistochemistry, and cellular localization was determined under light microscopy. The results of spontaneous abortions were compared to those of elective abortions. Results. The staining percentages of CD31, CD44, CD106, and E‐cadherin decreased in cases of spontaneous abortion, but CD54 (ICAM‐1) expression increased. Statistically significant differences were detected between spontaneous and elective abortion materials with regard to cytotrophoblasts (CTs), syncytiotrophoblasts (STs), and extravillous trophoblasts (EVTs) with the anti‐CD31 antibody (p = 0.0001). In addition, CD54 (p = 0.007 and p = 0.002) and E‐cadherin (p = 0.002 and p = 0.02) expression in CTs and STs, respectively, were significantly different. Furthermore, CD44 expression (p = 0.003) in decidual (D) cells and CD106 (p = 0.0001) expression in vessels of endometrial (E) and villous tissues were also significantly different. Conclusions. Decreased CD31 expression in CTs that invade the spiral arterioles and mimic E cells in spontaneous abortion cases suggests that CD31/PECAM‐1 is an important molecule in uteroplacental adequacy. Moreover, diminished expression of CD44 in D cells caused impaired stroma–villous connections. Enhancement of ICAM‐1 in placental and invading STs may be useful as a diagnostic marker for patients who may have a tendency to have spontaneous abortions. A down‐regulation of E‐cadherin was observed, which may be responsible for impaired CT differentiation and loss of the pregnancy. Furthermore, decreased VCAM‐1 expression in spontaneous abortions may be consistent with the importance of VCAM‐1 in trophoblast–endothelial cell interactions. Many adhesion molecules are known to be effective in the normal development of a pregnancy, and the analysis of adhesion molecules in spontaneous abortions will provide useful information for clarifying the physiopathology of spontaneous abortions.
Journal of Surgical Research | 2009
Ishak Ozel Tekin; Emine Yılmaz Sipahi; Mustafa Comert; Serefden Acikgoz; Gamze Yurdakan
BACKGROUND Intestinal ischemia/reperfusion (I/R) is a complex phenomenon causing destruction of both local and remote tissues, as well as multiple-organ failure. We investigated the role of lipid peroxidation in damage to intestinal, liver, and lung tissues in this pathology. MATERIALS AND METHODS The superior mesenteric artery was blocked for 30 min followed by 24 h of reperfusion. Tissues were removed and the presence of oxidized LDL, the activities of the superoxide dismutase enzyme, malondialdehyde levels, and inducible nitric oxide synthase expression were each evaluated in the intestinal, liver, and lung tissues. RESULTS While there was no staining in the control group tissues, ischemia/reperfusion resulted in positive oxidized LDL staining in all of the I/R test group tissue samples. Inducible nitric oxide synthase expression was significantly increased in the ischemia/reperfusion group tissues. Compared with those of the control group rats, the ischemia/reperfusion group tissues showed significantly higher malondialdehyde levels and lower superoxide dismutase activities. CONCLUSIONS This study demonstrated for the first time that oxidized LDL accumulated in the terminal ileum, liver, and lung tissues after intestinal ischemia/reperfusion. This occurrence (or the presence of oxidized LDL) may be an indicator of ongoing oxidative stress and enhanced lipid peroxidation. Augmentation of inducible nitric oxide synthase expression may play a role in progression of inflammation and LDL oxidation. These data support the hypothesis that cellular oxidative stress is a critical step in reperfusion-mediated injury in both the intestine and end organs, and that antioxidant strategies may provide organ protection in patients with reperfusion injury, at least through affecting interaction with free radicals, nitric oxide, and oxidized LDL.
Kaohsiung Journal of Medical Sciences | 2012
Gamze Yurdakan; Ishak Ozel Tekin; Mustafa Comert; Serefden Acikgoz; Emine Yılmaz Sipahi
Intestinal ischemia/reperfusion (I/R) is a complex phenomenon that causes destruction of both local and remote tissues. The objective of this study was to investigate the possible participation of oxidized low‐density lipoproteins (oxLDLs) and inducible nitric oxide synthase (iNOS) expression in renal tissue damage after intestinal I/R. The superior mesenteric artery was blocked for 30 minutes, followed by 24 hours of reperfusion. At the end of the reperfusion period, renal tissues were removed; the presence of oxLDL, superoxide dismutase enzyme activity, malondialdehyde levels, and iNOS expression were evaluated. I/R resulted in positive oxLDL staining in renal tissue. Compared with control rats, tissue from the I/R group showed significantly higher malondialdehyde levels and lower superoxide dismutase enzyme activity. Strong and diffuse iNOS expression was present in the I/R group. Our findings support the hypothesis that I/R of intestinal tissue results in oxidative and nitrosative stress and enhances lipid peroxidation in the end organ. These data show that oxLDL accumulates in rat renal tissue after intestinal I/R. Antioxidant strategies may provide organ protection in patients with reperfusion injury, at least by affecting interactions with free radicals, nitric oxide, and oxLDL. This study demonstrates for the first time that oxLDL may play a role in renal tissue damage after intestinal I/R. Antioxidant strategies may be beneficial for protection from reperfusion injury.
Clinical and Experimental Dermatology | 2010
Nilufer Onak Kandemir; Banu Dogan Gun; Burak Bahadir; Gamze Yurdakan; N. Ozdemir; Nimet Karadayi; Sukru Oguz Ozdamar
Background. Kaposi’s sarcoma is a multicentric, low‐grade, vascular neoplasia. Human herpesvirus 8 is associated with all epidemiological forms of KS and has been shown in vitro to induce the tyrosine receptor kinase c‐Kit in infected cells.
Journal of Investigative Surgery | 2013
Fatma Ayca Gultekin; Guldeniz Karadeniz Cakmak; Ummuhani Ozel Turkcu; Gamze Yurdakan; F. Ebru Ofluoğlu Demir; Mustafa Comert
ABSTRACT Aim: Similar protective effect of ischemic and ozone oxidative preconditioning (OzoneOP) in hepatic ischemia–reperfusion (I/R) injury was demonstrated, providing evidences that both preconditioning settings shared similar biochemical mechanisms of protection. We investigated the effects of OzoneOP on liver regeneration after 70% partial hepatectomy (PHx) in rats. Methods: Rats were divided into three groups: PHx, I/R + PHx, and OzoneOP + I/R + PHx groups. Ozone (intraperitoneal, 1.2 mg/kg) was given to rats subjected to I/R and 70% hepatectomy daily five times before operation. At 24 hr and 48 hr after resection, samples were collected for the measurement of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor alpha (TNF-α), and interleukin-6 (IL-6). Moreover, liver regeneration rate, proliferating cell nuclear antigen (PCNA) labeling index, mitotic index, and histopathological examination were evaluated. Results: OzoneOP reduced liver injury determined by liver histology and serum transaminases. There was a rise in serum TNF-α and IL-6 levels in the I/R + PHx group whereas OzoneOP significantly decreased the rise in the level of TNF-α but not IL-6 on the 24 hr and 48 hr of reperfusion. Moreover, liver regeneration in OzoneOP + PHx group, as assessed by the regenerated liver weight, mitotic, and PCNA-labeling index, was significantly improved when compared to I/R + PHx group. Conclusion: These results suggest that OzoneOP ameliorates the hepatic injury associated with I/R and has a stimulatory effect on liver cell regeneration that may make it valuable as a hepatoprotective modality.
Kaohsiung Journal of Medical Sciences | 2012
Figen Atalay; Gamze Yurdakan; Emine Yilmaz-Sipahi
Acute lung injury is an inflammatory syndrome that increases the permeability of the blood‐gas barrier, resulting in high morbidity and mortality. Despite intensive research, treatment options remain limited. We investigated the protective efficacy of tezosentan, a novel, dual endothelin receptor antagonist, in an experimental model of alpha‐naphthylthiourea (ANTU)‐induced acute lung injury in rats. ANTU was intraperitoneally (i.p.) injected into rats at a dose of 10 mg/kg. Tezosentan was injected 30 minutes before ANTU was subcutaneously (s.c.) injected at doses of 2, 10, or 30 mg/kg, 60 minutes before ANTU was injected at doses of 2, 10, or 30 mg/kg (i.p.), and 90 minutes before ANTU at a dose of 10 mg/kg (i.p.). Four hours later, the lung weight/body weight (LW/BW) ratio and pleural effusion (PE) were measured. When injected 30 minutes before ANTU at doses of 2, 10, or 30 mg/kg (s.c.), tezosentan had no effect on lung pathology. When injected 60 minutes before ANTU at doses of 2, 10, or 30 mg/kg (i.p.) or 90 minutes before ANTU (10 mg/kg, i.p.), tezosentan significantly decreased the PE/BW ratio and had a prophylactic effect on PE formation at all doses. Therefore, tezosentan may attenuate lung injury. Furthermore, its acute and inhibitory effects on fluid accumulation were more effective in the pleural cavity than in the interstitial compartment in this experimental model.
Experimental and Molecular Pathology | 2009
Nilufer Onak Kandemir; Gamze Yurdakan; Sibel Bektas; Nilgün Solak Tekin
Advances in Clinical and Experimental Medicine | 2014
Mehmet Kivanc Erdem; Gamze Yurdakan; Emine Yilmaz-Sipahi