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Dive into the research topics where Canan Demirtas is active.

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Featured researches published by Canan Demirtas.


Acupuncture in Medicine | 2012

Influence of acupuncture on leptin, ghrelin, insulin and cholecystokinin in obese women: a randomised, sham-controlled preliminary trial

Funda Güçel; Burak Bahar; Canan Demirtas; Setenay Mit; Cemal Çevik

Background Obesity is an energy balance problem caused by overeating. Obesity treatment includes diet, exercise, behaviour treatment, pharmacotherapy and surgery; in addition, acupuncture is also an option. Objective To investigate the effect of acupuncture on weight loss and whether a brief acupuncture treatment of 5 weeks can change circulating levels of leptin, ghrelin, insulin and cholecystokinin (CCK) in obese women. Methods 40 women with a body mass index (BMI)>30 kg/m2 were equally randomised to either an acupuncture group or a sham (non-penetrating) acupuncture group and received treatment at LI4, HT7, ST36, ST44 and SP6 bilaterally. Both groups had two sessions of 20 min/week for a total of 10 sessions. Serum insulin, leptin, plasma ghrelin and CCK levels were measured by ELISA. Results Acupuncture treatment decreased insulin and leptin levels and induced weight loss, together with a decrease in BMI compared with sham acupuncture. Furthermore, between-group analyses demonstrated increases in plasma ghrelin and CCK levels in subjects who received acupuncture treatment. Conclusion These findings suggest that acupuncture may help to regulate weight owing to its beneficial effects on hormones such as insulin, leptin, ghrelin and CCK in obese subjects even after a few weeks of treatment.


Journal of Surgical Research | 2012

Volatile anesthetic preconditioning attenuated sepsis induced lung inflammation

Nurdan Bedirli; Canan Demirtas; Taylan Akkaya; Bülent Salman; Murat Alper; Abdulkadir Bedirli; Hatice Pasaoglu

BACKGROUND This study aimed to evaluate the differential protective effects of isoflurane or sevoflurane on lung inflammation in a rat model of cecal ligation and puncture (CLP) induced sepsis. METHODS Seventy-two rats were assigned to control, sevoflurane, or isoflurane groups. At 2 and 4 h, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), nitrate/nitrate levels (NO), total antioxidant capacity (TAC), and intercellular cell adhesion molecule-1 (ICAM-1) were determined. At 12 and 24 h, malondialdehyde (MDA), myeloperoxidase (MPO), and histologic changes were evaluated. Survival was monitored for 7 d after CLP. RESULTS Sevoflurane (75%) and isoflurane (63%) significantly improved survival rate compared with control rats (38%). When sevoflurane and isoflurane groups were compared, sevoflurane pretreatment showed significant decrease in NO at 2 h [1045 (803-1274)/1570 (1174-2239) and 4 h [817 (499-1171)/1493 (794-2080)]; increase in TAC at 4 h [580.0 (387-751)/320 (239-512)]; decrease in MDA at 12 h [2.5 (1.1-4.2)/5.4 (4-73)] and 24 h [10.8 (6.0-14.0)/15.9 (9-28)]; and decrease in MPO at 24 h [145.8 (81-260)/232 (148-346)]. The difference in the ICAM-1 expression of the isoflurane and sevoflurane groups was not significant at both measurement times. The architectural integrity of the alveoli was preserved in all the groups. The injury scores of the three groups at 12 and 24 h did not show any significant difference. CONCLUSIONS Both sevoflurane and isoflurane attenuated inflammatory response, lipid peroxidation, and oxidative stress. Furthermore, sevoflurane was more effective in modulating sepsis induced inflammatory response at the chosen concentration in sepsis model.


International Journal of Surgery | 2009

Does sildenafil reverse the adverse effects of ischemia on ischemic colon anastomosis: yes, 'no'.

Oktay Irkorucu; Bulent Hamdi Ucan; Guldeniz Karadeniz Cakmak; Ali Ugur Emre; Oge Tascilar; Ebru Ofluoglu; Burak Bahadir; Kemal Karakaya; Canan Demirtas; Handan Ankarali; Gürkan Kertiş; Hatice Pasaoglu; Mustafa Comert

INTRODUCTION Sildenafil may lead an improvement in anastomotic healing of ischemic left colon anastomosis. METHODS Thirty-six male Wistar albino rats were randomized into four experimental groups (n=9 in each group). In group 1, a well-perfused left colonic segment was transected, and free ends were anatomosed. In groups 2, 3 and 4 animals underwent a standardized surgical procedure to induce ischemic left colon anastomosis. Group 2 animals received only tap water. In groups 3 and 4 animals received 10mg/kg/body-weight and 20mg/kg/body-weight sildenafil, single dose a day during 4 days, respectively. Rats were sacrificed on day 4 following operation. Anastomotic integrity, intra-peritoneal adhesion scores, anastomotic bursting pressures and tissue hydroxyproline levels were recorded. Histopathological examination of the anastomosis was also performed. RESULTS There was no statistically significant difference among groups with respect to anastomotic integrity (p=0.142) but ischemia decreased the anastomotic bursting pressure. The mean bursting pressure values were 78.8+/-24.1, 43.3+/-26, 55.1+/-32.4, and 43.3+/-20.4 in groups 1, 2, 3, and 4, respectively. Group 1 had the highest values whereas; there was no statistically significant difference between groups 1 and 3. There was no statistically significant difference among groups 2, 3, and 4 with respect to tissue hydroxyproline levels, adhesion scores and the Chiu scores. The highest inflammatory cell presence in the granulation tissue was detected in group 2, whereas the lowest was detected in group 4 (p=0.0001). The highest fibroblast infiltration in the granulation tissue was detected in group 1 (p=0.045). DISCUSSION Our results showed that 10mg/kg sildenafil decreased the adverse effects of ischemia on the healing of ischemic left colon anastomosis. Additional investigations are needed to confirm the effects of phosphodiesterase-5 inhibitors in ischemic colon anastomosis models.


Fertility and Sterility | 2014

Insulin resistance and its relationship with high molecular weight adiponectin in adolescents with polycystic ovary syndrome and a maternal history of polycystic ovary syndrome

Sevil Cankaya; Berfu Demir; Sezin Erturk Aksakal; Berna Dilbaz; Canan Demirtas; Umit Goktolga

OBJECTIVE To assess the rate of insulin resistance (IR) and the relationship between IR and high molecular weight (HMW) adiponectin in normal weight adolescents with polycystic ovary syndrome (PCOS) and a maternal history of PCOS. DESIGN Case-controlled study. SETTING Adolescent clinic of a teaching and research hospital. PATIENT(S) Forty normal weight adolescents with PCOS and a maternal history of PCOS and 40 normo-ovulatory age- and body mass index (BMI)-matched controls. INTERVENTION(S) A 75-g oral glucose tolerance test (OGTT) was performed for each participant. MAIN OUTCOME MEASURE(S) Homeostasis model assessment of IR and HMW adiponectin. RESULT(S) There were no statistically significant differences between the PCOS and control groups in terms of fasting glucose, fasting insulin, and lipid parameters. Although total and free T were significantly higher, HMW adiponectin levels were significantly lower in the PCOS group compared with the control group. When the PCOS group was compared according to the IR, the HMW adiponectin level was significantly lower in the adolescents with PCOS and IR. The adolescents with PCOS and biochemical hyperandrogenemia had significantly lower HMW adiponectin levels and significantly higher homeostasis model assessment of IR score compared with the adolescents with PCOS and normoandrogenemia. CONCLUSION(S) The adolescents with PCOS had a significantly increased rate of IR without clinical findings of metabolic disorders or obesity. The HMW adiponectin levels were negatively correlated with IR.


International Journal of Cardiology | 2016

Effect of serum YKL-40 on coronary collateral development and SYNTAX score in stable coronary artery disease

Mehmet Kadri Akboga; Ridvan Yalcin; Asife Sahinarslan; Canan Demirtas; Adnan Abaci

OBJECTIVE Many studies have revealed a role of YKL-40 as a new inflammatory biomarker in angiogenesis, inflammation, atherosclerosis and cardiovascular events. Thus, the aim of this study was to investigate the association of serum YKL-40 level with coronary collateral development and SYNTAX score in patients with stable coronary artery disease. METHODS A total of 165 patients who had ≥90% stenosis in at least one major coronary artery were prospectively enrolled in the study. Collateral degree was graded according to Rentrop-Cohen classification. Patients with grade 2 or 3 collateral degree were included in good collateral group and patients with grade 0 or 1 collateral degree were included in poor collateral group. The patients were also classified according to SYNTAX criteria, those with low (≤22) and those with high (>22) SYNTAX score. RESULTS Serum YKL-40 and hs-CRP levels were significantly lower in good collateral group. Furthermore, YKL-40 level showed significant positive correlations with SYNTAX score (r=0.486, p<0.001) and hs-CRP level (r=0.340, p<0.001). In multivariate regression analysis, serum YKL-40 (odds ratio: 0.928; 95% confidence interval: 0.917-0.940; p<0.001), duration of ischemic symptom and total occlusion were independent predictors of good collateral development. In ROC curve analysis, a YKL-40 value cut-off point of ≥168.5 predicted the high SYNTAX score with a sensitivity of 81.0% and specificity of 72.4%. CONCLUSIONS Increased serum YKL-40 level was related with poor collateral development and high SYNTAX score. According to these findings YKL-40 can be used as a predictor of good collateral development and high SYNTAX score.


Journal of Investigative Surgery | 2009

The Effects of Resveratrol on the Healing of Left Colonic Anastomosis

G. Karadeniz Cakmak; Oktay Irkorucu; Bulent Hamdi Ucan; Oge Tascilar; Ali Ugur Emre; Kemal Karakaya; Burak Bahadir; Serefden Acikgoz; Hatice Pasaoglu; Handan Ankarali; Ebru Ugurbas; Canan Demirtas; Mustafa Comert

Introduction: Resveratrol (RSV) is a natural polyphenolic compound found in grape skins and the red wine which improves histological reorganization of the regenerating tissue in dermal wound healing. Since anastomotic healing possesses paramount importance to prevent complications in colorectal surgery, the present study is aimed to evaluate the effect of RSV on the healing of experimental left colonic anastomoses. Methods: Thirty-two male Wistar albino rats were randomized into two groups and subjected to colonic anastomosis. The study group was treated with RSV and the control group received tap water instead. The rats were sacrificed 3 and 7 days postoperatively. Wound complications, intra-abdominal abscesses, and anastomotic leaks and stenosis were recorded. Four types of assessment were performed: bursting pressure, hydroxyproline (OHP) content, histopathology, and biochemical analysis. Results: Compared to the control group, the RSV-treated rats displayed a higher bursting pressure (p <. 001) and anastomotic OHP content (p <. 05)]. RSV treatment leads to significant increase in PON activity at both time points and decrease in malondialdehyde levels on postoperative day 3 (p <. 001). Histopathological analysis revealed that RSV administration leads to a better anastomotic healing in terms of mucosal ischemia, neovascularization, reepithelialization, fibroblast, and lymphocyte infiltration. Conclusion: The study results suggest that exogenous RSV administration exerts a positive effect on experimental colonic wound healing in the rat. Although the precise cellular mechanisms by which RSV enhances anastomotic wound healing is not clear, stimulation of neovascularization, generation of collagen synthesis, inhibition of overinflammation, and restriction of oxidative injury seems to be of paramount importance.


Renal Failure | 2008

The relationship of visfatin levels to inflammatory cytokines and left ventricular hypertrophy in hemodialysis and continuous ambulatory peritoneal dialysis patients.

Yasemin Erten; Fatma Ayerden Ebinç; Haksun Ebinç; Hatice Pasaoglu; Canan Demirtas; Gülten Taçoy; Eyup Koc; Ulver Derici; Kadriye Altok Reis; Musa Bali; Turgay Arinsoy; Sukru Sindel

Visfatin was recently defined as an adipocytokine; however, the pathophysiological role of visfatin is not completely understood. A few studies suggest that visfatin may be a new proinflammatory adipocytokine. The aim of the present study was to compare serum visfatin levels between hemodialysis and continuous ambulatory peritoneal dialysis (CAPD) patients and evaluate the relationship between visfatin levels to IL-6, TNF-α, and left ventricular hypertrophy. Serum visfatin, IL-6, and TNF-α levels were measured by using the ELISA method, and echocardiographic evaluations were performed in 31 hemodialysis patients, 30 CAPD patients, and 21 healthy volunteers. Serum visfatin levels were higher in the CAPD group (265.27 ± 387.86 ng/mL) than hemodialysis (97.68 ± 244.96 ng/mL,) and control (41.33 ± 48.87 ng/mL) groups (p = 0.04, p = 0.01, respectively). No significant difference was observed between the hemodialysis and control groups. In univariate analysis, visfatin levels were positively correlated with IL-6 (r = 0.24, p = 0.03), TNF-α (r = 0.34, p = 0.002), and BMI (r = 0.26, p = 0.03) and negatively correlated with some left ventricular diastolic parameters [Em and Em/Am (r = −0.305, p = 0.01), (r = −0.251, p = 0.03), respectively]. No relationship was found between visfatin and left ventricular mass index. In the linear regression analysis, visfatin levels independently related with TNF-( (β = 0.369, p = 0.001) and IL-6 (β = 0.284, p = 0.015). This study has found significantly higher levels of serum visfatin in CAPD patients when compared to healthy individuals. Increased visfatin levels seem to associate with proinflammatory cytokines such as IL-6 or TNF-α. As for the effects of on left ventricular structure and functions, visfatin might have negative effects on left ventricular diastolic function parameters but have no effects on left ventricular mass index.


Renal Failure | 2008

The Relationship among Asymmetric Dimethylarginine (ADMA) Levels, Residual Renal Function, and Left Ventricular Hypertrophy in Continuous Ambulatory Peritoneal Dialysis Patients

Fatma Ayerden Ebinç; Yasemin Erten; Haksun Ebinç; Hatice Pasaoglu; Canan Demirtas; Gülten Taçoy; Ruya Mutluay; Eyup Koc; Ulver Derici; Kadriye Altok Reis; Musa Bali; Turgay Arinsoy; Şükrü Sindel

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial-based nitric oxide synthase. Its level is increased by end stage renal disease. However, most studies showing an increase in ADMA in dialysis patients have focused on hemodialysis. Results with peritoneal dialysis patients have been more inconclusive. Recent studies suggest that ADMA may be a new cardiovascular risk factor. The aim of the present study was to evaluate the relationship between ADMA levels, residual renal function, and left ventricular hypertrophy in peritoneal dialysis patients. Serum ADMA measurements and echocardiographic evaluations were performed in 54 peritoneal dialysis patients and 26 healthy volunteers. Residual renal function was measured in peritoneal dialysis patients by urea clearance from a urine collection. Thirty-two of the 54 peritoneal dialysis patients had residual renal function. ADMA levels of the peritoneal dialysis group were found to be significantly higher than those of healthy individuals (p = 0.03). Within the peritoneal dialysis group, ADMA levels of patients with residual renal function were significantly lower than those without residual renal function (p = 0.01), though they were still higher than the ADMA levels of the control group (p = 0.04). Serum levels of ADMA were positively correlated with left ventricular mass index (r = 0.29, p = 0.01) and negatively correlated with early mitral inflow velocity (Em) (r = −0.28, p = 0.01), Em/Late mitral inflow velocity (Am) (r = −0,32, p = 0.00), and isovolumetric relaxation time (r = −0.30, p = 0.01). In conclusion, increased ADMA levels seem to be associated with left ventricular hypertrophy in peritoneal dialysis patients, and residual renal function may lead to a reduction of serum ADMA levels.


Journal of Maternal-fetal & Neonatal Medicine | 2016

Serum angiogenic profile in abnormal placentation.

Ebru Biberoglu; Ayse Kirbas; Korkut Daglar; Kutay Biberoglu; Hakan Timur; Canan Demirtas; Erdem Karabulut; Nuri Danisman

Abstract Objective: To evaluate the circulating soluble fms-like tyrosine kinase 1 (sFlt1), placental growth factor (PlGF) and vascular endothelial growth factor (VEGF) levels in women with abnormal placentation and to compare the data with the results of women with normal pregnancy. Material and methods: Serum biomarkers of angiogenesis and maternal and perinatal characteristics of 68 pregnant women, all in the third trimester, who were diagnosed to have vaginal bleeding due to complete placenta previa with and without concomitant placenta accreta, increta and percreta as the study group and 30 pregnant women without any placentation abnormality who eventually delivered at  ≥37 weeks of gestational age as the control group were evaluated. Results: There was no statistical difference in the maternal serum values of sFlt1, PlGF, sFlt1/PlGF ratio and VEGF in groups with placental abnormality as compared to controls. Not even a single case of preeclampsia and intrauterine fetal growth restriction was encountered in the study group. Conclusion: We demonstrated that regardless of the localization and the degree of the myometrial invasion of the placenta in the uterus, the circulatory biomarkers of angiogenesis and vascularization were comparable.


Journal of Surgical Research | 2013

Effects of adrenomedullin and vascular endothelial growth factor on ischemia/reperfusion injury in skeletal muscle in rats

Mehmet Kirişçi; Gursel Levent Oktar; Candan Ozogul; Eser Öz Oyar; Seda Nur Akyol; Canan Demirtas; Mustafa Arslan

BACKGROUND In this study we investigated the effects of adrenomedullin (AM) and vascular endothelial growth factor (VEGF) on skeletal muscle ischemia/reperfusion (I/R) injury in a rat model. MATERIALS AND METHODS Thirty-six Wistar rats were randomized into six groups (n = 6). Laparotomy was performed in all groups under general anesthesia. Nothing else was done in Group S (Sham). The Group I/R underwent I/R performed by clamping and declamping of the infrarenal abdominal aorta for 120 min, respectively. Group VEGF and Group AM received intravenous infusion of VEGF (0.8 μg/kg) or AM (12 μg/kg) respectively, without I/R. Group I/R + VEGF and Group I/R + AM received intravenous infusion of VEGF (0.8 μg/kg) or AM (12 μg/kg) immediately after 2 h period of ischemia, respectively. At the end of reperfusion period, skeletal muscle samples of lower extremity were taken from all groups for biochemical and histopathologic examinations. RESULTS Tissue levels of malondialdehyde (MDA), superoxide dismutase (SOD), nitric oxide (NO), and hypoxia inducible factor 1 alpha (HIF 1α) were found to be significantly higher in Group I/R than the levels in Group S (P < 0.05). Tissue levels of MDA, SOD, NO, and HIF 1α were significantly lower in Group I/R + AM compared with the levels in Group I/R (P < 0.05). In Group I/R + VEGF, tissue levels of MDA and NO were significantly lower than the levels in Group I/R (P < 0.05). No statistically significant difference was found in the tissue levels of catalase among the groups. Histologic examination revealed a larger central muscular necrosis than the peripheral necrosis, red blood cells in the lumens of capillary vessels, and a stronger atrophy and elliptical or round shape in muscle fibers in Group I/R. Terminal deoxynucleotidyl transferase mediated dUPT nick end labeling (TUNEL)-positive cell count was significantly lower in groups I/R + AM and I/R + VEGF than Group I/R (P < 0.0001, P < 0.0001, respectively). CONCLUSIONS These results indicate that AM and VEGF have protective effects on I/R injury in skeletal muscle in a rat model.

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Ali Ugur Emre

Zonguldak Karaelmas University

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