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Öğe Dietary addition of caffeic acid phenethyl ester protects myocardial tissue against ethambutol induced oxidative stress(2013) Yavuz C.; Demirta S.; Yazici S.; Çalikan A.; Güçlü O.; Karahan O.; Mavitaş B.Objective: 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 damage.Öğe Evaluating the anti-angiogenic properties of iloprost and dipyridamole in the chick embryo chorioallantoic membrane model(Scientific Publishers of India, 2014) Guclu O.; Karahan O.; Yazici S.; Caliskan A.; Demirtas S.; Yavuz C.; Muratoglu A.Dipyridamole 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 anti-angiogenic 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 The investigation of the antiangiogenic potential of amiodarone HCl in the chick embryo chorioallantoic membrane model(2013) Karahan O.; Yavuz C.; Demirtas S.; Caliskan A.; Atahan E.Angiogenesis, 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 10-6M 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 10-5M and 10-6M, but that result was statistically insignificant. The antiangiogenic effect scores of Bevacizumab at the concentrations of 10-4M and 10-5M were significantly higher than that of 10-6M. This effect of Amiodarone may be important for determining routine antiarrhythmic doses.Öğe Use of C-type natriuretic peptide as an indicator in detection of inducible peripheral ischemia(Baycinar Medical Publishing, 2014) C¸alis¸kan A.; Yazici S.; Karahan O.; Gü?lü O.; Tezcan O.; Demirtas¸ S.; Yildiz B.Background: In this experimental study, alterations in plasma C-type natriuretic peptide (CNP) levels were evaluated during the critical initial hours of peripheral ischemia. Methods: Forty male Sprague-Dawley type rats (aged 8 to 12 weeks, weighing 230±30 g) were included in the study. Four groups were created with 10 rats namely control group, group 1, group 2, and group 3. Baseline plasma CNP levels were detected in the control group without any intervention, while the plasma CNP levels were determined in the second hour of peripheral ischemia in group 1. Plasma CNP levels were determined in the fifth hour of peripheral ischemia for group 2, whereas plasma CNP levels were determined in group 3 at the eighth hour of peripheral ischemia. Results: The baseline plasma CNP levels were 0.285±0.011 pmol/L in the control group. In rats with peripheral ischemia, a significant time-dependent increase was detected in plasma levels of CNP (p<0.05). The plasma CNP levels were detected as 0.350±0.015, 0.486±0.084, and 0.534±0.048 pmol/L in group 1, 2, and 3 respectively. Conclusion: Plasma CNP, an endothelium-derived vasodilator, is associated with the cellular response in ischemic tissues in a time-dependent manner.Öğe The VKORC1 gene homozygous polymorphism is markedly higher in Crimean Congo hemorrhagic fever patients(2013) Turkdogan K.A.; Karabacak M.; Akpinar O.; Karahan O.; Güven F.M.K.; Engin A.; Turkdogan F.T.In Crimean-Congo Hemorrhagic Fever (CCHF), the main target of the virus is endothelial cells, monocytes and hepatocytes. The virus in these cells leads to the development of capillary vessels dysfunction, which induces clinical and pathological changes during the disease. Increase in capillary permeability and coagulation dysfunction constitute a tendency to bleed. In the current study, we aimed to investigate the relationship between VKORC1 and bleeding tendency in CCHF. Forty-eight consecutive patients with a laboratory-confirmed diagnosis of CCHF were treated with blood products, and 37 healthy volunteers as the control group were prospectively enrolled into the study. The DNA was obtained from each sample using PCR amplification method, and VKORC1 1639 G>A gene polymorphisms were scanned in the DNA samples. In CCHF group of patients with bleeding VKORC1 gene were analyzed. Normal genotype was detected in 5 (22.7%) patients, homozygote mutation was detected in 2 (9.1%) patients and heterozygote mutation was detected in 15 (68.2%) patients, respectively. Furthermore, the G allele frequency was statistically higher in study group (51 [53%] vs. 27 [36%]) (p<0.005). It seems to be that VKORC1 gene A allele frequencies saliently higher in CCHF. This might be associated with increased bleeding risk in CCHF. Analyzing of VKORC1 gene polymorphisms could help in the risk stratification of patients with CCHF.
