Yazar "Yavas, G." seçeneğine göre listele
Listeleniyor 1 - 6 / 6
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Amelioration of Radiation-Induced Intestinal Toxicity by Beta-Hydroxy-Beta-Methyl-Butyrate, L-Glutamine, and L-Arginie: Results of an Experimental Study(Elsevier Science Inc, 2016) Yavas, C.; Yavas, G.; Celik, E.; Buyukyoruk, A.; Buyukyoruk, C.; Yuce, D.; Ata, O.[Abstract Not Availabe]Öğe Amelioration of radiation-induced lung injury by halofuginone: An experimental study in Wistar-Albino rats(Sage Publications Ltd, 2017) Calik, M.; Yavas, G.; Calik, S. G.; Yavas, C.; Celik, Z. E.; Sargon, M. F.; Esme, H.To evaluate effects of halofuginone (H) on radiation-induced lung injury (RILI), 60 rats were divided into six groups: Group (G) 1 control, G2 radiotherapy (RT) only, G3 and G4 2. 5 and 5 g H and G5 and G6 RT + 2.5 and 5 g H groups, respectively. A single dose of 12 Gy RT was given to both lungs. H was applied intraperitoneally with daily doses, until animals were killed at 6 and 16 weeks after RT. At 6th and 16th weeks of RT, five rats from each group were killed. Lung tissues were dissected for light and electron microscopy. Chronic inflammation, fibrosis and transforming growth factor-beta (TGF)- scores of all study groups were significantly different at 6th and 16th week (p < 0.001). Chronic inflammation, fibrosis and TGF- scores of G2 were higher than G5 and G6 at 6th and 16th weeks of RT. At 16th week, fibrosis and TGF- scores of G5 were higher than G6 (p = 0.040 and 0.028, respectively). Electron microscopical findings also supported these results. Therefore, H may ameliorate RILI. The effect of the H was more prominent at higher dose and after long-term follow-up. These findings should be clarified with further studies.Öğe Assessment of concomitant versus sequential trastuzumab on radiation-induced cardiovascular toxicity(Sage Publications Ltd, 2017) Yavas, G.; Gultekin, M.; Yildiz, O.; Seyrek, M.; Demirkol, S.; Toy, H.; Sargon, M. F.There are limited data regarding effect of trastuzumab on radiation-induced cardiovascular toxicity when used sequentially or concomitantly. This experimental study aims to investigate effect of trastuzumab on radiation-induced cardiovascular toxicity with respect to the treatment sequence. One hundred and eight female Wistar albino rats were divided into six groups (G): G1 was control, G2 was trastuzumab, and G3 was radiotherapy (RT); G4 and G6 were sequential RT and trastuzumab; and G5 was concomitant RT and trastuzumab groups, respectively. Rats were killed at 6th h, 21st and 70th days after RT; thoracic aorta and heart samples were obtained. Transthoracic echocardiography and functional studies evaluating relaxation of thoracic aorta were performed. Subendothelial edema scores of thoracic aorta samples at 21st and 70th days were higher in RT groups (G3, G4, G5, and G6) (p < 0.001). There was a deterioration of relaxation responses of thoracic aorta samples in RT groups (p < 0.001). Cardiac fibrosis (CF) scores revealed detrimental effect of RT beginning from 6th h and trastuzumab from 21st day. RT groups showed further deterioration of CF at 70th day. Ejection fraction, left ventricular mass, and fractional shortening were significantly decreased in G4, G5, and G6. Trastuzumab may increase pathological damage in cardiovascular structures when used with RT regardless of timing.Öğe Evaluation of the acute effect of palonosetron on transmural dispersion of myocardial repolarization(Verduci Publisher, 2012) Dogan, U.; Yavas, G.; Tekinalp, M.; Yavas, C.; Ata, O. Y.; Ozdemir, K.Background: 5-hydroxytryptamine receptor type-3 (5-HT3) antagonists are widely used for prophylaxis of chemotherapy-induced nausea and vomiting (CINV) and regarded to have a high safety profile. However, several electrocardiographic changes and cardiac arrhythmias have been reported due to administration of 5-HT3 antagonists. Only prolongation of QT interval has been investigated as an index of potential for life-threatening arrhythmias in adult patients using 5-HT3 antagonists. Recently, increase in transmural dispersion of repolarization (TDR) has been proposed as a more reliable determinant of arrhythmogenic potential. Aim: To assess the effects of palonosetron, a second-generation 5-HT3 antagonist, on the T-wave peak to T-wave end (TpTe) interval which has been proposed as a reliable index of spatial TDR. Patients and Methods: A total of 50 consecutive cancer patients (aged: 57 +/- 12 years) who were scheduled to receive emetogenic chemotherapy were included to the study. Baseline12-lead electrocardiography (ECG) recordings were obtained. Then, all patients received 8 mg intravenous dexamethasone followed by a single dose of 0.25 mg intravenous palonosetron administered over 30 seconds. A second ECG was performed 30 minutes after the administration of palonosetron. Indices of cardiac repolarization and TOR before and after the administration of palonosetron were compared. Results: In comparison with baseline there was no statistically significant change in any of the heart rate-corrected parameters, including QT(c) (lead V-5), QT(maxc), QT(minc), QT(cd), TpTe (V-5), TpTe(max), TpTe(min), TpTe(d) and TpTe/QT (V-5). Conclusions: Palonosetron does not have any significant effect on QT(c) and TpTe intervals. It might be the drug of choice for prophylaxis of CINV in cancer patients receiving chemotherapy with known cardiotoxic potential or who have pre-existing cardiac disease that predispose them to drug-induced arrhythmias.Öğe Imiquimod Attenuates Radiation-Induced Pulmonary Fibrosis(Elsevier Science Inc, 2018) Calik, M.; Yavas, G.; Celik, E.; Yavas, C.; Calik, G.; Sargon, M.; Sanli, Y.[Abstract Not Availabe]Öğe The use of concurrent hormonotherapy and radiotherapy does not deteriorate radiation-induced cardiac toxicity(Sage Publications Ltd, 2017) Yavas, C.; Yavas, G.; Toy, H.; Ata, O.Postmenopausal patients with breast cancer have two options for adjuvant endocrine therapy, tamoxifen and aromatase inhibitors (AIs) as well as radiotherapy (RT) and chemotherapy. However, there is limited data regarding the optimal sequencing of RT and tamoxifen/AIs. Thus, we aimed to evaluate the effects of tamoxifen and AIs on radiation-induced cardiotoxicity. Eighty ovariectomized rats were divided into eight groups (G). G1 was defined as a control group; G2, G3, G4, and G5 were RT, tamoxifen, anastrozle, and letrozole groups, respectively; G6, G7, and G8 were RT plus tamoxifen, anastrozle, and letrozole groups, respectively. Drugs were started 1 week before RT and continued until the animals were killed 16 weeks after RT. The heart tissues were then dissected and examined with light microscopy to determine endocardial thickness and cardiac fibrosis. The endocardial thickness scores of both RT alone and the tamoxifen groups as well as the cardiac fibrosis score of RT alone were higher than that the control group (p < 0.05 for all). There was no difference in the endocardial thickness and cardiac fibrosis scores of the RT-only group and the RT plus hormonotherapy groups (p > 0.05 for all). Concurrent administration of RT and hormonal therapy with either tamoxifen or AIs did not further amplify radiation-induced cardiac toxicity. This issue warrants further study.
