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Öğe Clinical impact and biomaterial evaluation of autologous platelet gel in cardiac surgery(2008) Gunaydın, Serdar; McCusker, Kevin; SarıT.; Onur, Mehmet Ali; Gürpınar, A.; Sevim, Handan; Zorlutuna, Y.We compared the clinical efficacy of autologous platelet gel (APG) and gelatine (CONT), including biomaterial evaluation. In a prospective, randomized, controlled trial, 64 patients undergoing complex coronary artery bypass graft (CABG) surgery and/or aortic surgery, in whom the surgeon was able to identify a bleeding site for which conventional means to stop bleeding were impractical or proved unsuccessful, were enrolled. Aortic punch biopsy from each patient was harvested in explant cell (EC) culture media. Hemostasis success for the "oozing" category was 89% in APG and 60% in CONT (p<0.05). For the "heavy bleeding" category, the success rates were 92% in APG and 45% in CONT (p<0.01). Contact of gelatine inhibited EC proliferation and APG increased cell cycling and EC quantity. Phagocytic capacity (PC) was significantly higher in the APG group (p<0.001). APG was significantly better than CONT with respect to hemostatic success rate, effects on wound healing and increased resistance to infection (PC). © 2008 SAGE Publications.Öğe Clinical performance and biocompatibility of hyaluronan-based heparin-bonded extracorporeal circuits in different risk cohorts(Oxford Univ Press, 2010) Gunaydin, Serdar; McCusker, Kevin; Sari, Tamer; Onur, Mehmet Ali; Zorlutuna, YamanThis prospective randomized study compares novel hyaluronan-based heparin-bonded circuits vs. uncoated controls across EuroSCORE patient risk strata including biomaterial evaluation. Over a two-year period, 90 patients undergoing coronary artery bypass grafting were prospectively randomized to one of the two perfusion protocols: Group 1 was treated with hyaluronan-based heparin-bonded preconnected circuits (Vision HFO-GBS (TM), Gish, CA, USA) and Group 2 with identical uncoated controls. Each group was composed of three subgroups (n = 15) with respect to preoperative evaluation of low (EuroSCORE 0-2), medium (3-5) and high (6+) risk patients. Blood samples were collected after induction (T1) and heparinization (T2), 15 min after cardiopulmonary bypass start (T3), before cessation of CPB (T4), 15 min after reversal (T5), and the first postoperative day (T6). In high-risk patients, platelet counts demonstrated significant preservation at T4, T5 and leukocyte counts were lower at T5 in hyaluronan group (P <= 0.05 vs. control). C3a (ng.ml(-1)) levels were significantly lower at T3 (0.2 +/- 0.04 vs. 0.31 +/- 0.05), T4 (0.25 +/- 0.04 vs. 0.51 +/- 0.05), T5 (0.38 +/- 0.04 vs. 0.56 +/- 0.05) and interleukin-6 (pg.ml(-1)) at T4 (91 +/- 18 vs. 124 +/- 20), T5 (110 +/- 20 vs. 220 +/- 25) in coated group vs. control (P <= 0.05). Protein desorption (microalbumin) on fibers (mg.mm(-3)) was less in hyaluronan vs. control groups (P <= 0.05). Hyaluronan coating reduced platelet adhesion and cell adsorption, and modulated inflammatory response in high-risk patients. (c) 2010 Published by European Association for Cardio-Thoracic Surgery. All rights reserved.Öğe Comparison of polymethoxyethylacrylate-coated circuits with leukocyte filtration and reduced heparinization protocol on heparin-bonded circuits in different risk cohorts(Sage Publications Ltd, 2006) Günaydin, Serdar; McCusker, Kevin; Vijay, Venkataramana; İşbir, Selim; Sari, Tamer; Onur, Mehmet Ali; Zorlutuna, YamanObjectives: The relative benefits of strategic leukofiltration on polymer-coated and low-dose heparin protocol on heparin-coated circuits were studied across EuroSCORE patient risk strata for three different cohorts. Methods: In a prospective, randomized study, 270 patients undergoing coronary artery bypass grafting were allocated into three groups (n = 90): Group 1 - polymethoxyethylacrylate-coated circuits + leukocyte filters; Group 2 - polypeptide-based heparin-bonded circuits with reduced heparinization; and Group 3 - Control: uncoated circuits. Each group was further divided into three subgroups (n = 30), with respect to low- (EuroSCORE 0-2), medium- (3-5), and high- (6+) risk patients. Blood samples were collected at T1: following induction of anesthesia; T2: following heparin administration; T3: 15 min after CPB; T4: before cessation of CPB; T5: 15 min after protamine reversal; and T6: ICU. Results: In high-risk cohorts, leukocyte counts demonstrated significant differences at T4 and T5 in Group 1, and at T4 in Group 2. Platelet counts were preserved significantly better at T4 and T5 in both groups (p < 0.05 versus control). Serum IL-2 and C3a levels were significantly lower at T3, T4 and T5 in Group 1, and T4 and T5 in Group 2 (p < 0.05). Postoperative bleeding, respiratory support time and incidence of atrial fibrillation were lower in the study groups versus control. Cell counts on filter mesh and heparin-coated fibers/ circuits were significantly higher in the high-risk cohorts versus uncoated fibers. Phagocytic capacity increased on filter mesh, especially in high-risk specimens. SEM evaluation demonstrated better preserved coated circuits. Conclusion: Leukofiltration and coating reduced platelet adhesion, protein adsorption, atrial fibrillation and reduced heparinization acted via modulation of systemic inflammatory response in high-risk groups.Öğe Isolation, culturing and characterization of rat adipose tissue-derived mesenchymal stem cells: a simple technique(Tubitak Scientific & Technical Research Council Turkey, 2012) Niyaz, Mehmet; Gurpinar, Ozer Aylin; Gunaydin, Serdar; Onur, Mehmet AliIn this study, our aim was to develop a new simple technique for isolation of mesenchymal stem cells from adipose tissue. For this purpose, mesenchymal stem cells were isolated from rat adipose tissue by using the primary explant culture technique. When the cells became confluent, they were passaged 4 times by using the standard trypsinization method with trypsin/EDTA solution. Cells at second passage were characterized by using immunofluorescence staining against CD13 and CD29 markers. The results showed that these cultured cells were positive for CD13 and CD29 markers. Flow cytometry analysis was also done against CD29, CD90, CD54, MHC Class I, CD45, CD 106, and MHC Class II for characterization of mesenchymal stem cells. The results of flow cytometry analysis showed that these cells were mesenchymal stem cells. Half of the cells were cryopreserved at all passages for future applications. It is thought that these mesenchymal stem cells can be used in therapy of cardiovascular diseases as an alternative technique in the near future.