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Öğe Application of thoracic endovascular dissecting aneurysm repair for secondary type B aortic dissection(Clinics Cardive Publ Pty Ltd, 2015) Karahan, Oguz; Tezcan, Orhan; Demirtas, Sinan; Caliskan, Ahmet; Yavuz, CelalType A aortic dissection is an emergency condition that requires immediate surgery. Graft replacement of the ascending aorta is the main treatment for this disorder. However, after ascending aortic replacement, the dissection flap may progress to the distal side (to the descending aorta) and a new intimal tear may develop. In this study, we report on a 66-year-old woman who had a history of ascending aortic replacement six months earlier. She was admitted to hospital with a new onset of back pain. Computed tomography revealed a new dissection tear originating from the distal side of the subclavian artery orifice. Thoracic endovascular dissecting aneurysm repair (TEVDAR) was carried out on the patient. Additional complications were not observed in the postoperative period. Complete cure was provided and the patient was discharged on the fourth day after the operation. TEVDAR may be safe and effective in preventing progression of the aortic flap and the formation of a new intimal tear in type A aortic dissections. Optional hybrid interventions could ameliorate the outcomes in aortic dissection cases.Öğe Association between oxidative stress index and serum lipid levels in healthy young adults(Pakistan Medical Assoc, 2014) Turkdogan, Kenan Ahmet; Akpinar, Orhan; Karabacak, Mustafa; Akpinar, Hatice; Turkdogan, Figen Tunali; Karahan, OguzObjectives: To investigate the relationship between lipid levels and oxidative stress index in healthy young adults. Methods: The study was camed out at the Department of Emergency Service, Faculty of Medicine, Cumhuriyet University, Sivas, Turkey, between January 2011 and July 2012. A total of 100 healthy adult volunteers were enrolled in the study. Venous blood samples (10 ml) were collected from all individuals, and serum lipid parameters, total antioxidant capacity and total oxidative levels were studied. SPSS 15 was used for statistical analysis. Results: Overall, there were 84 (84%) males and 16 (16%) females. The mean age fo the male population was 30 +/- 3 years, while that of the females was 31 +/- 3 years. Overall age ranged from 25 to 35 years. A statistically significant correlation was found between the oxidative stress index and serum cholesterol (p<0.001; r=0.596), triglyceride (p<0.001; r=0.476) and low-density lipoprotein levels (p<0.001; r=0.318). However, no significant correlation was found between oxidative stress index and serum high-density lipoprotein levels (p=0.564; r=0.058). Conclusion: The results showed that even at an early age, there is a direct linear correlation between oxidative stress and serum lipid levels.Öğe Can calcium dobesilate be used safely for peripheral microvasculopathies that require neoangiogenesis?(Int Scientific Literature, Inc, 2013) Demirtas, Sinan; Caliskan, Ahmet; Guclu, Orkut; Yazici, Suleyman; Karahan, Oguz; Yavuz, Celal; Mavitas, BinaliBackground: Calcium dobesilate (CaD) is a member of the synthetic veno-active drug family. Only a small number of reports are available that describe the micro-angiogenic effects of CaD in the current literature. Material/Methods: The antiangiogenic potential of CaD was compared with bevacizumab (Bb), which is a potent angiogenesis inhibitor, in a chick chorioallantoic membrane model. Four different concentrations (10-7, 10-6, 10-5, and 10-4 M) of drug pellet were prepared for each drug. Changes in vessel formation were scored and compared for each drug according to the previous literature. Result: The antiangiogenic behavior of CaD was lower than Bb, despite the significant dose-dependent manner of escalation. The anti-angiogenic scores of CaD were determined as 0.20, 0.47, 0.66, 1.0 in 10-7, 10-6, 10-5, and 10-4 M concentrations, respectively (average score >0.5 was significant). Conclusions: According to the data obtained, this agent should be used carefully for cases in which angiogenesis plays an important role in healing.Öğe Can elevated prolidase activity predict the duration of ischemic exposure in different types of ischemia?(Baycinar Medical Publ-Baycinar Tibbi Yayincilik, 2013) Yavuz, Celal; Guclu, Orkut; Demirtas, Sinan; Karahan, Oguz; Yazici, Suleyman; Caliskan, Ahmet; Celik, YusufBackground: This study aims to determine the relationship between serum prolidase activity and ischemia duration in different ischemia types. Methods: Forty male Sprague Dawley rats were divided into five equal groups. The rats were sacrificed and blood samples were obtained to determine the basal serum prolidase levels in group 1 (control group) without any intervention. In groups 2 and 3, the superior mesenteric arteries were clamped with simple laparotomy to induce mesenteric ischemia. In groups 4 and 5, the right common femoral artery was clamped to induce peripheral ischemia and blood samples were taken at 120 and at 360 minutes, respectively. The serum prolidase levels were measured using the samples obtained from each group. Results: The basal prolidase level in rats was found to be 266.8 +/- 20.5 U/L. The serum prolidase levels increased after two-hours of peripheral (404.0 +/- 105.6 U/L) and mesenteric ischemia (317.1 +/- 121.4 U/L). However, the serum prolidase levels decreased after six-hours of peripheral (346.1 +/- 104.9 U/L) and mesenteric ischemia (233.4 +/- 36.6 U/L). Although the serum prolidase levels were elevated in the second hour of mesenteric ischemia, they were lower than the enzyme levels obtained after two-hours of peripheral ischemia (p=0.006). Conclusion: The serum prolidase level may be an important predictive biomarker for identifying the duration of ischemia.Öğe Clinical features and patency rates of Remedy® biodegradable peripheral stents(Clinics Cardive Publ Pty Ltd, 2016) Tiryakioglu, Selma Kenar; Tiryakioglu, Osman; Karahan, Oguz; Demirtas, Sinan; Gokalp, Fatih; Erkoc, Kamuran; Ozkan, HakanObjective: The aim of this study was to investigate the mid-term results of Remedy (R) biodegradable stents, which have recently come into use for lower-extremity arterial occlusive disease. Methods: Sixty-five patients, who underwent surgical intervention in various cardiovascular surgery clinics throughout Turkey, were included in the study. The total number of stents used was 92. The mean age of the patients was 64.11 +/- 24.13 years (20-82), and 16 (24.6%) were female. The mean number of stents per patient was 1.42, and 70.7% of the lesions were TASC type A. Patients were followed for a mean of 32 months. Sixty-five patients underwent a control examination using either digital subtraction angiography or colour Doppler ultrasonography. In-stent restenosis was defined as >= 50% stenosis in the stent area in asymptomatic patients. The procedure was repeated if the degree of stenosis was >= 70%. Results: During the follow-up period, restenosis (>= 50% stenosis) was observed in seven patients (10.7%). The patency rate after secondary intervention was 100%, and there was no loss of limbs in any patient. Restenosis was observed in six patients with superficial femoral artery stents, and in one patient with a popliteal arterial stent. Conclusion: Our experience shows that Remedy (R) biodegradable peripheral stents were safe and effective in our cohort of patients, with acceptable patency rates.Öğe Comparison of Renoprotective Effect of Dabigatran With Low-Molecular-Weight Heparin(Sage Publications Inc, 2016) Yazici, Suleyman; Karahan, Oguz; Oral, Mehmet Kerem; Bayramoglu, Zehra; Unal, Mehmet; Caynak, Baris; Sagbas, ErtanObjective: The susceptibility of tissue to ischemia-reperfusion (I/R) injury is a major obstacle to tissue regeneration and cellular survival. In this study, we investigated the possible renoprotective effect of dabigatran in an experimental renal I/R model. Method: A total of 25 rats were randomly divided into 5 equal groups. The control group was used to obtain basal values of oxidant and antioxidant biomarkers. The sham group was used to obtain renal prolidase and malondialdehyde (MDA) levels after renal ischemia (for 45 minutes) and reperfusion (for 1 hour). A standard diet was followed. Oral 15 mg/kg dabigatran etexilate was administrated to group I, intraperitoneal 250 U/kg enoxaparin sodium was administrated to group II, and intraperitoneal 250 U/kg bemiparin sodium was administrated to group III for 1 week before the renal I/R was performed. Renal tissue samples were obtained during the first hour of reperfusion to detect renal prolidase and MDA levels in these groups, after which the rats were euthanized. Results: Renal prolidase levels were significantly higher in the sham group compared with the control group (1834.2 982.3 U/g protein vs 238.8 +/- 43.6U/g protein; P = .001). Lower prolidase levels were observed in groups II (838.7 +/- 123.8 U/g protein) and III (1012.9 +/- 302.3 U/g protein), and the lowest prolidase levels occurred in group I (533.8 +/- 96.2 U/g protein; P < .05) when compared with the sham group. The MDA levels were significantly lower (P < .05) in groups I, II, and III (163.9 +/- 41.5, 185.4 +/- 51.0, and 138.2 +/- 22.6 mol/g protein, respectively) compared with the sham group. Conclusion: Dabigatran etexilate, a univalent direct thrombin inhibitor, may protect the renal tissue more effectively when compared to low-molecular-weight heparins.Öğe Diagnostic accuracy of mean platelet volume in thromboangiitis obliterans(Sage Publications Ltd, 2014) Yavuz, Celal; Caliskan, Ahmet; Karahan, Oguz; Demirtas, Sinan; Yazici, SuleymanThromboangiitis obliterans (TAO) affects small-and medium-sized vessels of the extremities via a non-atherosclerotic inflammatory process in the elderly. Although diagnostic criteria have been determined, only a few studies have been described in the laboratory features. Diagnostic biomarkers are important for reducing disruptions caused by TAO. The diagnostic importance of mean platelet volume (MPV) was investigated in TAO patients. Forty-four patients diagnosed with TAO (study group) and 45 healthy individuals (control group) were included in the study. The age, gender and complete blood parameters obtained via peripheral venous blood samples were compared between the two groups. A receiver operating characteristic (ROC) curve was used for determining the diagnostic accuracy of the MPV variable. All the variables were statistically similar in each group except MPV and platelet counts. MPV was significantly higher and platelet count was significantly lower in the TAO group (P < 0.05). In addition, diagnostic accuracy was measured by the area under the ROC curve (Figure 1), and MPV differs significantly (P < 0.001), with a value of 0.783 (95% CI: 0.711-0.854). This study indicates that MPV is probably an important diagnostic predictor in TAO patients. Detection of blood parameters such as platelet properties is important for meticulous care of these patients.Öğe Diagnostic value of plasma C-type natriuretic peptide levels in determination of the duration of mesenteric ischaemia(Clinics Cardive Publ Pty Ltd, 2014) Demirtas, Sinan; Karahan, Oguz; Yazici, Suleyman; Guclu, Orkut; Caliskan, Ahmet; Tezcan, Orhan; Yavuz, CelalObjective: Mesenteric arteries release C-type natriuretic peptide (CNP), which hyperpolarises vascular smooth muscle. We measured the levels of this peptide after inducing mesenteric ischaemia over a series of time intervals, so as to determine its predictive value in demonstrating the severity of ischaemia in a rat model. Methods: A total of 32 rats were allocated to four groups containing eight rats each. Basal CNP reference levels were measured in the control group, which was not exposed to any intervention. In groups I, II and III, mesenteric ischaemia was induced over three, six and nine hours, respectively, and plasma CNP levels were measured afterwards. Mesenteric ischaemia was induced by clamping the superior mesenteric artery. Results: In comparison with the controls (2.38 +/- 0.18 pg/ml), CNP levels were relatively lower in group I (2.54 +/- 0.42 pg/ml). However, significant increases in plasma CNP levels were observed over longer periods of ischaemia in group II, at 5.23 +/- 0.22 pg/ml, and in group III, at 6.19 +/- 0.67 pg/ml (p < 0.05). A significant direct relationship was determined between plasma CNP levels and prolonged intervals of mesenteric ischaemia (R = 0.56, p < 0.001). Conclusion: Measuring plasma CNP levels in patients with acute mesenteric ischaemia may be beneficial in estimating the time period over which the ischaemic injury has occurred.Öğe DIETARY ADDITION OF CAFFEIC ACID PHENETHYL ESTER PROTECTS MYOCARDIAL TISSUE AGAINST ETHAMBUTOL INDUCED OXIDATIVE STRESS(Nobel Ilac, 2013) Yavuz, Celal; Demirtas, Sinan; Yazici, Suleyman; Caliskan, Ahmet; Guclu, Orkut; Karahan, Oguz; Mavitas, BinaliObjective: The myocardial effect of ethambutol (ETM) has not yet been clarified. The main purpose of this study was to determine both the oxidative status in myocardial tissue after administration of ETM and the adjuvant benefits of caffeic acid phenethyl ester (CAPE). Material and Method: Twenty four male rats were divided into three experimental groups as follows: a control group (without any drug administration) was created for obtaining normal myocardial tissue; an ETM group (rats received only ETM for thirty days) was created for ethambutol administration; and an ETM+CAPE group was created for administration of the full regimen (rats received ETM+CAPE for thirty days). Rats were sacrified at the end of day 30 and heart tissues were obtained for histopathological and biochemical examination. Oxidant and antioxidant parameters were biochemically investigated in all tissue samples. Results: In the ETM group, myocardial malondialdehyde (MDA) levels and total oxidant status (TOS) were significantly higher than in the control group (p<0.001). Conversely, total antioxidant capacity (TAC), the activity of superoxide dismutase (SOD) and of serum paraoxonase (PON1) were reduced in the ETM group (p<0.05). Furthermore, MDA and TOS activity was significantly reduced in the ETM+CAPE group (p<0.05); TAC, SOD and PON1 activities were increased with adjuvant CAPE therapy (in the ETM+CAPE group) rather than in the ETM group. Conclusion: ETM may lead to increased myocardial oxidative stress due to lipid peroxidation. Nevertheless, adjuvant CAPE administration seems to provide a partial enhancement of myocardial damageÖğe Do Dose-related Mechanisms Exist for the Angiogenic Behaviours of Heparin Derivatives?(Wiley, 2012) Yavuz, Celal; Karahan, Oguz[Abstract Not Available]Öğe Effectiveness of the cascade filtration technique in the management of inoperable leg ischemia(Baycinar Medical Publ-Baycinar Tibbi Yayincilik, 2013) Demirtas, Sinan; Yavuz, Celal; Caliskan, Ahmet; Karahan, Oguz; Vural, Ahmet Hakan; Ozyazicioglu, Ahmet FatihBackground: This study aims to investigate the effectiveness of the cascade filtration technique in individuals with peripheral vascular disease who are candidates for amputation. Methods: Twelve patients (9 males, 3 females; mean age 62.4 +/- 7.2 years; range 45 to 75 years) were included in the study. For the evaluation of the efficacy of this procedure, measurements of serum albumin, fibrinogen, immunoglobulin M, alpha-2 macroglobulin, low density lipoprotein (LDL) cholesterol, fibronectin, von Willebrand factor levels, blood viscosity, and transcutaneous oxygen saturation (tcPO(2)) were obtained before and after the procedure at sessions 1, 4, and 7. Results: A statistically insignificant increase in tcPO(2) values and a significant decrease in viscosity were determined (p=0.019). Fibronectin, von Willebrand factor, and viscosity levels were significantly decreased at the end of protocol, compared to baseline values. Various degrees of improvement were noted in seven of the 10 patients. After the completion of the protocol, amputation from a more distal level than previously planned was performed in three patients. Conclusion: Cascade filtration, despite its high cost, appears to be an effective treatment alternative which limits or prevents amputation.Öğe Evaluating the anti-angiogenic properties of Iloprost and Dipyridamole in the chick embryo chorioallantoic membrane model(Allied Acad, 2014) Guclu, Orkut; Karahan, Oguz; Yazici, Suleyman; Caliskan, Ahmet; Demirtas, Sinan; Yavuz, Celal; Muratoglu, AbdurrahmanDipyridamole is an antithrombotic agent that is widely used in the treatment of many vascular disorders. Also, the prostacyclin analogue iloprost has been utilized to salvage limbs in patients with severe limb ischemia. In this study we investigated whether dipyridamole and iloprost have anti-angiogenic properties and their anti-angiogenic properties were compared to bevacizumab, a known inhibitor of angiogenesis, using the in vivo chick chorioallantoic membrane animal model. Agar pellets were prepared with three different drug concentrations at 10(-6) M, 10(-5) M, and 10(-4) M. For each drug concentration twenty fertilized eggs were used. The entire experiment was performed in duplicate. Blood vessel density and loss were examined and scored under a stereoscopic microscope. For the 10(-4) M, 10(-5) M and 10(-6) M concentrations, the anti-angiogenic scores of iloprost were 0.2, 0.1 and 0.05, respectively. In the same order, the anti-angiogenic scores for dipyridamole were 0.2, 0.3 and 0.8. The antiangiogenic scores for bevacizumab were significantly higher than dipyridamole and iloprost over all concentrations (p<0.05). There were no significant differences found between the anti-angiogenic scores for iloprost and dipyridamole for all concentrations (p>0.05). Iloprost demonstrated no anti-angiogenic properties in the chorioallantoic membrane animal model, while dipyridamole did exhibit very weak anti-angiogenic activity only at very high doses of 10(-4) M. These results reveal that both agents can be prescribed safely for the treatment of medical conditions that require angiogenesis to facilitate healing.Öğe Evaluation of Pericardial Fluid C-Type Natriuretic Peptide Levels in Patients Undergoing Coronary Bypass Surgery(Georg Thieme Verlag Kg, 2017) Guclu, Orkut; Karahan, Oguz; Karabacak, Mustafa; Yuksel, Volkan; Huseyin, Serhat; Mavitas, BinaliBackground Neurohumoral and hemodynamic mechanisms have an effect on cardiac activity. C-type natriuretic peptide (CNP) is accessible in the cardiovascular system. The aim of this study was to determine whether CNP concentrations in pericardial fluid and blood are related to cardiac dysfunction in patients undergoing coronary artery bypass graft surgery. Materials and Methods In this study, 40 patients undergoing coronary artery bypass grafting were enrolled. The patients were separated into two groups according to left ventricular (LV) ejection fraction (EF): group 1 contained 28 patients with normal LV systolic function (LVEF >= 50%) and group 2 contained 12 patients with impaired LV systolic function (LVEF < 45%). Plasma and pericardial fluid samples were acquired during surgery to measure CNP levels. Results In group 1, CNP levels were detected to be 0.46 +/- 0.10 ng/mL in plasma and 0.66 +/- 0.8 ng/mL in pericardial liquid. In group 2, these levels were 0.51 +/- 0.09 and 0.79 +/- 0.12 ng/mL, respectively. CNP levels were determined to be significantly higher in patients with low EF compared with those with normal EF in pericardial fluid concentrations (p = 0.013). Conclusions CNP level in pericardial fluid is a more sensitive and proper marker of LV dysfunction than CNP levels in plasma. To the best of our knowledge, this study is the first to examine pericardial fluid CNP levels in patients undergoing coronary artery bypass surgery. It may have a valuable role in organizing cardiac remodeling and hypertrophy.Öğe Evaluation of the Vasoplegic impact of Papaverine in the rat aorta(Pakistan Medical Assoc, 2014) Yavuz, Celal; Callskan, Ahmet; Karahan, Oguz; Demirtas, Sinan; Yazici, Suleyman; Guclu, Orkut; Donmez, SonerObjective: To identify the degree of vasoplegic affinity of papaverine to rat thoracic aortas following constriction caused by adrenalin, serotonin and potassium chloride in an in-vitro model. Methods: The in vitro vasoplegic efficacy of papaverine against adrenalin (10(-5) M), serotonin (5HT) (10(-4) M), and KCI (60 mM) was assessed, using a rat aortic vasospasm model in an organ bath. First, aortic rings were constricted with a submaximal dose of vasoconstrictor agents. The samples were then incubated with papaverine (3x10(-4) M) for 20 minutes, followed by readministration of the same vasoconstrictor agents. The first vasospastic response (before papaverine incubation) and the new vasoconstrictor responses (after papaverine incubation) of the vessels were then compared. Results: The vasoplegic effect of vasoconstrictor agents in decreasing order was observed as adrenalin>KCI>5HT. This different affinity for the vasoplegic effect is considered to be a temporary impact of the drugs and the maximal inhibition of vasoconstriction was detected for the adrenalin receptor. Conclusion: The relevance of the macromolecules is responsible for the permanent efficacy of the drugs. Different degrees of vasoconstriction were also obtained after papaverine administration, which suggests that different responses can occur as a result of different stimulation of receptor modulators.Öğe Factor-Xa inhibitors protect against systemic oxidant damage induced by peripheral-ischemia reperfusion(Springer, 2014) Caliskan, Ahmet; Yavuz, Celal; Karahan, Oguz; Yazici, Suleyman; Guclu, Orkut; Demirtas, Sinan; Mavitas, BinaliFactor-Xa inhibitors are often used for prophylaxis and for the treatment of thrombotic vascular disorders. However, it is not known whether they are beneficial during the recanalization of the thrombotic vascular segment and during tissue reperfusion. Herein, we describe an animal study that was designed to investigate the possible protective effects and antioxidant properties of factor-Xa inhibitors. Forty rats were included in the study and were randomly divided into five equal groups. The first group served as a control group from which we obtained basal oxidant and antioxidant parameters. Peripheral ischemia was induced in the second group (sham group) for 6 h, and plasma levels of nitrogen oxide (NOx), prolidase and malondialdehyde (MDA) were obtained after 30 min of reperfusion. The sham group did not receive any drugs. Oral rivaroxaban (3 mg/kg) was administrated to Group III, intraperitoneal enoxaparin sodium (250 U/kg) was administrated to Group IV, and intraperitoneal bemiparine sodium (250 U/kg) was administrated to Group V 1 week prior to the induction of peripheral ischemia (for 6 h)-reperfusion. After 30 min of reperfusion, blood samples were obtained and NOx, prolidase and MDA levels in these groups were detected, and the rats were sacrificed. NOx levels were statistically similar (p > 0.05) between Groups I, II, III, IV, and V (20.7 +/- A 10.4, 17.4 +/- A 9.7, 25.9 +/- A 24.2, 27.0 +/- A 11.9, 23.3 +/- A 17.3 mu mol/L, respectively). MDA levels were significantly lower (p < 0.05) in Groups III (rivaroxaban), IV (enoxaparin sodium), and V (bemiparine sodium) (24.9 +/- A 11.9, 25.9 +/- A 4.4, 25.4 +/- A 10.8 mu mol/L, respectively) when compared with the sham group (Group II) (75.6 +/- A 24.3 mu mol/L). Prolidase levels were higher (p > 0.05) in the ischemia reperfusion groups (659.2 +/- A 130.6 in II (sham), 1,741.0 +/- A 1,530.6 in III (rivaroxaban), 2,453.8 +/- A 1,590.4 in IV (enoxaparin sodium), and 889.2 +/- A 574.7 U/g in V (bemiparine sodium) than in the control group (144.6 +/- A 131.8 U/g). Ischemia-reperfusion events may occur in prothrombotic disorders. During these events, prophylactic or therapeutic factor-Xa inhibitors can protect against thrombosis and oxidative reperfusion injury. The new oral factor-Xa inhibitor, rivaroxaban, appears to provide the same antioxidant support as injectable low molecular weight heparins (LMWHs).Öğe Human ischemia modified albumin can be a predictive biomarker for the detection of peripheral ischemia duration(Drunpp-Sarajevo, 2012) Yavuz, Celal; Caliskan, Ahmet; Yazici, Suleyman; Karahan, Oguz; Guclu, Orkut; Demirtas, SinanBackground: Human ischemia modified albumin (IMA) provides diagnostic and prognostic information for acute coronary ischemia. However, its role in peripheral ischemic disorders is unclear. The aim of this study is to detect the association between ischemia duration and the discriminator value of serum IMA levels in rat model with created peripheral ischemia. Methods: Thirty-two male Sprague-Dawley rats were included in the study. The rats were divided into four equal groups. The rats in Group I were sacrificed to determine the basal serum values of IMA without any application. The rats in Group II, the sham group, were applied with simple femoral incision only. The rats in Group III and IV had their common femoral artery clamped with classic femoral incision. Blood samples were taken after 120 minutes of ischemia in Group III and after 360 minutes of ischemia in Group IV, respectively. The serum ischemia modified albumin levels were detected using the blood samples. The results were compared statistically. Results: Obtained IMA levels were similar in the sham (Group II) and baseline (Group I) groups (p>0.05). The serum IMA levels were determined as 33 +/- 4 (33) mu/L, 36 +/- 9 (34) mu/L and 57 +/- 19 (61) mu/L in Groups I, III and IV, respectively. High IMA levels were found in advanced ischemia duration. The increase in serum IMA levels with time was statistically significant as can be seen in Figure 1 (p<0.05). Conclusion: Peripheral ischemic disorders can cause extremity loss if not treated immediately. In addition, delayed treatments may have fatal results. Therefore, timing is important in such cases. We suggest that serum IMA levels may be beneficial for the determination of ischemia duration in peripheral ischemia. They may also improve the predictive values of other standard biomarkers of ischemia.Öğe Hyperbaric Oxygen Preconditioning Provides Preliminary Protection Against Doxorubicin Cardiotoxicity(Taiwan Soc Cardiology, 2017) Tezcan, Orhan; Karahan, Oguz; Alan, Mustafa; Ekinci, Cenap; Yavuz, Celal; Demirtas, Sinan; Ekinci, AysunBackground: Doxorubicin (DOX) is generally recognized to have important cardiotoxic side effects. Studies are contradictory about the interaction between hyperbaric oxygen (HBO2) therapy and doxorubicin-induced cardiomyotoxicity. Recent data suggests that HBO2 therapy can lead to preconditioning of myocardium while generating oxidative stress. Herein we have investigated the effect of HBO2 therapy in a DOX-induced cardiomyocyte injury animal model. Methods: Twenty-one rats were divided into three equal groups as follows: 1) Group 1 is a control group (without any intervention), used for evaluating the basal cardiac structures and determining the normal value of cardiacs and serum oxidative markers; 2) Group 2 is the doxorubicin group (single dose i.p. 20 mg/kg doxorubicin) for detecting the cardiotoxic and systemic effects of doxorubicin; 3) Group 3 is the doxorubicin and HBO2 group (100% oxygen at 2.5 atmospheric for 90 minutes, daily), for evaluating the effect of HBO2 in doxorubicin induced cardiotoxicity. At the end of the protocols, the hearts were harvested and blood samples (2 ml) were obtained. Results: The doxorubicin treated animals (Group 2) had increased oxidative stress markers (both cardiac and serum) and severe cardiac injury as compared to the basal findings in the control group. Nevertheless, the highest cardiac oxidative stress index was detected in Group 3 (control vs. Group 3, p = 0.01). However, histological examination revealed that cardiac structures were well preserved in Group 3 when compared with Group 2. Conclusions: Our results suggest that HBO2 preconditioning appears to be protective in the doxorubicin-induced cardiotoxicity model. Future studies are required to better elucidate the basis of this preconditioning effect of HBO2.Öğe Investigation of possible prophylactic, renoprotective, and cardioprotective effects of thromboprophylactic drugs against ischemia-reperfusion injury(Elsevier Taiwan, 2015) Demirtas, Sinan; Karahan, Oguz; Yazici, Suleyman; Guclu, Orkut; Caliskan, Ahmet; Tezcan, Orhan; Kaplan, IbrahimThe aim of this study was to investigate whether anticoagulant and antiaggregant agents have protective effects against oxidative damage induced by peripheral ischemia ereperfusion (I/R). Groups were created as follows: control group, I/R group (sham group), I/R plus acetylsalicylic acid (Group I), I/R+clopidogrel (Group II), I/R+rivaroxaban (Group III), I/R+bemiparin sodium (Group IV), and I/R+enoxaparin sodium (Group V). In Groups I, II, III, IV, and V, drugs were administered daily for 1 week before I/R creation. Peripheral I/R was induced in the I/R groups by clamping the right femoral artery. The rats were sacrificed 1 hour after reperfusion. Nitrogen oxide levels, malondialdehyde (MDA) levels, paraoxonase-1 (PON1) activity, and prolidase activity were evaluated in both cardiac and renal tissues. There was no significant difference in nitrogen oxide levels between the groups. However, cardiac and renal MDA were significantly higher and PON1 activity was markedly lower in the I/R groups compared with the control group (p < 0.05). Although elevated prolidase activity was detected in both the cardiac and renal tissue of the I/R groups, only the sham group and Group V had significantly higher renal prolidase activity (p < 0.05). Group V had significantly higher cardiac MDA, PON1, prolidase levels, and renal prolidase activity compared with the sham group (p < 0.05). Significant improvement in renal MDA levels was only observed in Group III, and marked improvement was observed in the cardiac MDA levels of Group II when compared with the sham group (p < 0.05). Thromboprophylactic agents appear to provide partial or prominent protection against I/R injury. Copyright (C) 2015, Kaohsiung Medical University. Published by Elsevier Taiwan LLC. All rights reserved.Öğe Investigation of the antiangiogenic behaviors of rivaroxaban and low molecular weight heparins(Lippincott Williams & Wilkins, 2014) Yavuz, Celal; Caliskan, Ahmet; Karahan, Oguz; Yazici, Suleyman; Guclu, Orkut; Demirtas, Sinan; Mavitas, BinaliAntithrombotic agents play important roles in the prophylactic and therapeutic management of many cardiovascular disorders. Therefore, many researchers have focused on developing new strategies for anticoagulation. New oral anticoagulants and factor Xa inhibitors are products of such research. Although they are identified as advantageous, there are limited data available about their multisystemic interactions. Thus, the antiangiogenic behaviors of oral factor Xa inhibitors and low molecular weight heparins (LMWHs) were investigated in this study. The chick chorioallantoic membrane (CAM) model was designed to investigate the antiangiogenic potential of new oral factor Xa inhibitors (rivaroxaban) and LMWHs (enoxaparin sodium and tinzaparin sodium). Four different molar concentrations (10(-4), 10(-5), 10(-6), and 10(-7) mu mol/l) were studied for each drug. Each concentration was studied on 20 fertilized eggs. Vessel structures were evaluated under a stereoscopic microscope, and vessel formation was scaled according to previous literature. Both enoxaparin and tinzaparin sodium have increased antiangiogenic efficacy on CAM in a dose-dependent manner. However, this increased efficacy did not reach significant levels (average score < 0.5). On the contrary, while rivaroxaban showed dose-dependent antiangiogenic properties similar to enoxaparin and tinzaparin, a significant average antiangiogenic score (0.7) was detected at 10(-4) mu mol/l concentrations. New oral anticoagulants seem to be more favorable. However, their safety for the cardiovascular system needs to be clarified through microsystem studies on, for example, angiogenesis.Öğe The Investigation of the Antiangiogenic Potential of Amiodarone HCl in the Chick Embryo Chorioallantoic Membrane Model(Allied Acad, 2013) Karahan, Oguz; Yavuz, Celal; Demirtas, Sinan; Caliskan, Ahmet; Atahan, ErhanAngiogenesis, which plays a significant role in a variety of physiological processes, such as embryonic growth and wound healing, is strictly delimited and finely tuned by a balance of proangiogenic and antiangiogenic factors. Cardiac rhythm disorders are diseases that are often accompanied by vascular pathologies. As such, the purpose of this study was to investigate the antiangiogenic effects of Amiodarone HCl in the chorioallantoic membrane model. In this study, the antiangiogenic effect of Amiodarone HCl was compared with a positive control group that was given pure paraffin and the vascular endothelial growth factor inhibitor Bevacizumab, as well as a negative control group in which clearly antiangiogenic activity was shown in this model previously. Concentrations of 10(-4), 10(-5), and 10(-6)M of each drug were administered. For the purpose of determining the antiangiogenic effects of the drugs, blood vessels of the chorioallantoic membranes were evaluated using a stereoscopic microscope. The antiangiogenic effect scores of Amiodarone HCl at the dose of 10(-4) molar (M) were higher than those of 10(-5)M and 10(-6)M, but that result was statistically insignificant. The antiangiogenic effect scores of Bevacizumab at the concentrations of 10(-4)M and 10(-5)M were significantly higher than that of 10(-6)M. This effect of Amiodarone may be important for determining routine antiarrhythmic doses.
