Özaçmak, Veysel Haktan | Sayan, Hale | Aktunç, Erol

Other | 2009 | Türk Biyokimya Dergisi34 ( 2 ) , pp.82 - 88

Amaç: Adenozin ve adenozin A1 reseptör agonistleri, çeşitli dokuların reperfüzyon harabiyetine karşı önkoşullanma yoluyla koruyucu etkiler göstermektedir. Çalışmanın amacı, sıçan ince bağırsağının reperfüzyon harabiyeti üzerine adenozin A1/A2 reseptör aktivasyonunun etkilerini incelemekti. Yöntemler: Denekler herbiri rastgele sekiz hayvan içeren dört gruba ayrıldı: sham kontrol, iskemi-reperfüzyon kontrol, 5’-N-etilkarboksiamidoadenozin (NECA) (non-selektif A1 /A2 agonisti, 0.1 mg/kg, i.v.) tedavili iskemi-reperfüzyon ve teofilin (non-selektif A1 /A2 antagonisti, 20 mg/kg, i.v.) tedavili iskemi-reperfüzyon. Tedaviler iskemi yapılmad . . .an 5 dk önce uygulandı. Süperiyor mezenter arter 30 dk klempe edildikten sonra reperfüzyon dönemi 180 dk sürdü. Terminal ileum segmentlerinin, KCl, karbakol ve substans P’ye olan kasılma yanıtlarının kaydedilmesinin yanısıra, dokuların miyeloperoksidaz, malondialdehit ve indirgenmiş glutatyon miktarları da ölçüldü. Bulgular: İskemi, nötrofil infiltrasyonu ve lipid peroksidasyonunu ileri düzeyde yükseltirken aynı zamanda indirgenmiş glutatyonu düşürdü. Sham control grubuy- la karşılaştırıldığında, kasılma yanıtları iskemi-reperfüzyon grubunda ciddi düzeyde azaldı. NECA ön tedavisi, doku indirgenmiş glutatyon miktarını ileri derecede düzeltti ve ayrıca iskemi-reperfüzyon sonucu azalmış kasılma yanıtını kısmen iyileştirdi. Teofilin ile ön tedavi ise herhangi koruyucu bir etki göstermedi. Sonuç: Adenozin A1 /A2 reseptör aktivasyonunun, iskemi sonucu gelişen bağırsak kasılma bozukluğuna karşı kısmi koruma sağladığını ve ayrıca bu korumanın, indirgenmiş glutatyon düzeyinin fizyolojik seviyede tutulması yolu ile muhtemelen gerçekleştiğine dair ek kanıt önermekteyiz. Objectives: Adenosine and adenosine A1 receptor agonists exert protective effects against reperfusion injury in different tissues by mediating preconditioning. The aim of the present study was to examine the effects of adenosine A1 /A2 receptor activation on reperfusion-induced small intestinal injury in rat. Methods: Animals were randomized into four groups each including eight as following: sham control, ischemia-reperfusion control, 5’-N-ethylcarboxamidoadenosine (NECA) (non-selective A1 /A2 agonist, 0.1 mg/kg, i.v.)-treated I/R, and theophylline (non-selective A1 /A2 antagonist, 20 mg/kg, i.v.)-treated I/R groups. The treatments were administered 5 min before inducing ischemia in which superior mesenteric artery was clamped for 30 min followed by 180 min of reperfusion pe- riod. Myeloperoxidase, malondialdehyde, and reduced glutathione contents of terminal ileum samples were measured besides recording contractile responses to KCl, carbachol and substance P. Results: Ischemic insult significantly increased neutrophil infiltration and lipid peroxidation while decreasing the reduced glutathione. Contractile responses were seriously reduced in I/R group compared to that of the sham control group. NECA pretreatment alleviated the tissue content of reduced glutathione remarkably besides providing partial amelioration of I/R-reduced contractile response, while theophylline pretreatment had no any protective effect. Conclusion: We offer additional evidence that activation of A1 /A2 adenosine receptors provides partial protection against ischemia-induced intestinal contractile dysfunction possibly through maintaining reduced glutathione content at physiological levels Daha fazlası Daha az

Kolsal, Ebru | Tekin, İshak Özel | Pişkin, Etem | Aydemir, Cumhur | Akyüz, Mehmet | Çabuk, Hasan | Eldes, Nilüfer | Numanoğlu, Kemal Varın

Article | 2009 | Journal of Clinical Apheresis24 ( 1 ) , pp.21 - 24

Tricyclic antidepressant poisoning is one of the most common causes of serious intoxication. Here, we report a 2-year-old girl with severe amitriptyline (70 mg/kg) intoxication. She was in comatose, had generalized tonic clonic seizure, ventricular tachycardia, and wide QRS complexes. Although she did not respond to classical therapies, very good clinical response to plasmapheresis was obtained and she developed no complications. Thus, plasmapheresis may be an effective treatment modality in poisoning with drugs, which bind to plasma proteins with high affinity. © 2009 Wiley-Liss, Inc.

Kalaycı, Özlem A. | Cömert, Füsun B. | Hazer, Baki | Atalay, Turgay | Cavicchi, Kevin A. | Çakmak, Mükerrem

Article | 2010 | Polymer Bulletin65 ( 3 ) , pp.215 - 226

The synthesis, spectroscopic characterization, and antimicrobial efficiency of gold and silver nanoparticles embedded in novel amphiphilic comb-type graft copolymers having good film-forming properties have been described. Amphiphilic comb-type graft copolymers were synthesized by the reaction of chlorinated polypropylene (PP) (Mw = 140,000 Da) with polyethylene glycol (PEG) (Mn = 2,000 Da) at different molar ratios. Metal nanoparticles embedded graft copolymers were prepared by reducing solutions of the salts of silver or gold and the copolymer in tetrahydrofuran. The optical properties of the metal nanoparticle embedded copolymers . . . were determined by using UV-visible spectroscopy. Surface plasmon resonance (SPR) of the gold and silver nanoparticle embedded copolymers in toluene was observed at a maximum wavelength (?max) of 428 and 551 nm in the UV-VIS absorption spectra, respectively. The average particle diameters of the gold and silver nanoparticles were found to be 50 nm from the high resolution scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Amphiphilic polymer films containing silver and gold nanoparticles were found to be highly antimicrobial by virtue of their antiseptic properties to Escherichia coli and Staphylococcus aureus. © Springer-Verlag 2009 Daha fazlası Daha az

Çakmaklı, Birten | Hazer, Baki | Tekin, İshak Özel | Cömert-Beğendik, Füsun

Article | 2005 | Biomacromolecules6 ( 3 ) , pp.1750 - 1758

Peroxidation, epoxidation, and/or perepoxidation reactions of soybean oil under air at room temperature resulted in cross-linked polymeric soybean oil peroxides on the surface along with the waxy soluble part, sPSB, with a molecular weight of 4690, containing up to 2.3 wt % peroxide. This soluble polymeric oil peroxide, sPSB, initiated the free radical polymerization of either methyl methacrylate (MMA) or n-butyl methacrylate (nBMA) to give PSB-g-PMMA and PSB-g-PnBMA graft copolymers. The polymers obtained were characterized by 1H NMR, thermogravimetric analysis, differential scanning calorimetry, and gel permeation chromatography t . . .echniques. Polymeric oil as a plasticizer lowered the glass transition of the PSB-g-PMMA graft copolymers. PSB-g-PMMA and PSB-g-PnBMA graft copolymer film samples were also used in cell culture studies. Fibroblast and macrophage cells were strongly adhered and spread on the copolymer film surfaces, which is important in tissue engineering. Bacterial adhesion on PSB-g-PMMA graft copolymer was also studied. Both Staphylococcus epidermidis and Escherichia coli adhered on the graft copolymer better than on homo-PMMA. Furthermore, the latter adhered much better than the former. © 2005 American Chemical Society Daha fazlası Daha az

Sayan, Hale | Özaçmak, Veysel Haktan | Güven, Aysel | Aktaş, R. Gülhan | Özaçmak, I. Diler

Article | 2006 | Journal of Investigative Surgery19 ( 3 ) , pp.163 - 173

Erythropoietin exerts hematopoietic effects by stimulating proliferation of early erythroid precursors. Nonhematopoietic effects of erythropoietin have also been shown. It may act as a new angiogenic factor in wound healing. This study aimed to investigate the effect of systemic administration of recombinant human erythropoietin on wound healing in mice. Dorsal incisional wounds were performed in mice, which were then divided into two groups; a group treated for 7 days with recombinant human erythropoietin, and a control group. Sacrificing animals on day 7, the wound tissues were collected for analysis of wound breaking strength, ma . . .londialdehyde, a marker of lipid peroxidation, hydroxyproline, an index of reparative collagen deposition, reduced glutathione levels, and for histological evaluation. The immunohistochemical determination of vascular endothelial growth factor (VEGF) which is believed to be the most prevalent angiogenic factor throughout the skin repair process, was also studied. The treatment significantly increased wound breaking strength by decreasing malondialdehyde and increasing hydroxyproline levels on day 7 after wounding. No statistically meaningful change was observed in reduced glutathione content. VEGF was immunostained significantly more on wound tissue of treated animals compared to the control group. Recombinant human erythropoietin treatment may be effective in wound healing due to inhibition of lipid peroxidation, deposition of collagen, and VEGF expression in wound area. Copyright © Taylor & Francis Group, LLC Daha fazlası Daha az

Özaçmak, Veysel Haktan | Özaçmak-Sayan, Hale

Other | 2010 | Türk Geriatri Dergisi13 ( 3 ) , pp.160 - 165

Giriş: Turmeriğin majör komponenti olan kurkumin hem antioksidan hem de antiinflamatuar aktivite göstermektedir. Çalışmamızda, kronik serebral hipoperfüzyon modelini kullanarak, overleri alınmış dişi sıçan beyininde, kurkuminin oksidatif stresi azaltıp azaltmadığını araştırdık. Gereç ve Yöntem: Kronik serebral hipoperfüzyon, her iki karotid komunis arterin kalıcı ligasyonu ile sağlandı. Denekler (4-6 aylık toplam 30 adet yetişkin Wistar Albino dişi sıçanlar) rastgele üç gruba ayrıldı: sham kontrol, iskemi ve 14 gün boyunca günlük kurkumin (100 mg/kg) verilen iskemi grubu. Ligasyon sonrası 14üncü günde tüm gruplardaki beyin dokuların . . .ın malondialdehid (MDA) ve indirgenmiş glutatyon (GSH) içerikleri ölçüldü. Bulgular: İskemi, MDA içeriğinin ileri dercede yükselmesine neden olurken GSH seviyesini anlamlı derecede azalttı. Diğer yandan, kurkumin tedavisi iskemik beyin dokusunda anlamlı derecelerde MDA düzeyini düşürerek ve GSH içeriğini yükselterek, değerlerin sham grubundakiler seviyesine geri dönmesini sağladı. Sonuç: Elde ettiğimiz sonuçlar, vasküler demansın deneysel hayvan modeli olan kronik serebral hipoperfüzyonda kurkuminin hem oksidatif stresi hem de lipid peroksidasyonunu azalttığını önermektedir. Altta yatan moleküler mekanizmaların derinlemesine daha fazla araştırılması sonrasında inanıyoruz ki kurkuminin tedavideki verimliliği, klinik uygulamalar için özellikle de vasküler demanslı menopoz sonrası yaşlı kadınlarda test edilmesine layık olacaktır. Introduction: Curcumin, the major constituent of turmeric, exhibits both antioxidant and anti-inflammatory activities. In the present study, we investigated whether or not curcumin reduces oxidative stress in ovariectomized female rat brain by using a model of chronic cerebral hypoperfusion. Materials and Method: Chronic cerebral hypoperfusion was induced by permanent ligation of both common carotid arteries. Animals (a total of 30 adult female Wistar Albino rats, 4-6 months old) were randomly divided into three groups: sham control, ischemia, and ischemia plus daily curcumin treatment (100 mg/kg) for 14 days. At day 14 after the ligation, malondialdehyde (MDA) and reduced glutathione (GSH) contents of brain tissues were measured in all groups. Results: Ischemia caused a significant increase in MDA content but a meaningful decrease in GSH levels. Treatment with curcumin, however, lowered MDA and elevated GSH contents significantly in ischemic brain tissue, bringing their levels back to that of the sham group. Conclusion: Our results suggest that curcumin attenuates both oxidative stress and lipid peroxidation in chronic cerebral hypoperfusion, which is an animal model of vascular dementia. Following further in depth investigations into underlying molecular mechanism(s), we believe that therapeutic efficacy of curcumin deserves to be tested for potential clinical application especially in postmenopausal elderly women suffering from vascular dementia Daha fazlası Daha az

Armutçu, Feraf | Coşkun, Ömer Faruk | Gürel, Aykut | Şahin, S. | Kanter, Marek | Cihan, Ali | Numanoğlu, Kemal Varın

Article | 2005 | Cell Biology and Toxicology21 ( 1 ) , pp.53 - 60

Acetone may induce oxidative stress leading to disturbance of the biochemical and physiological functions of red blood cells (RBCs) thereby affecting membrane integrity. Vitamin E (vit E) is believed to function as an antioxidant in vivo protecting membranes from lipid peroxidation. The aim of the present study was the evaluation of possible protective effects of vit E treatment against acetone-induced oxidative stress in rat RBCs. Thirty healthy male Wistar albino rats, weighing 200-230 g and averaging 12 weeks old were randomly allotted into one of three experimental groups: Control (A), acetone-treated (B) and acetone + vit E-tre . . .ated groups (C), each containing ten animals. Group A received only drinking water. Acetone, 5% (v/v), was given with drinking water to B and C groups. In addition, C group received vit E dose of 200 mg/kg/day i.m. The experiment continued for 10 days. At the end of the 10th day, the blood samples were obtained for biochemical and morphological investigation. Acetone treatment resulted in RBC membrane destruction and hemolysis, increased thiobarbituric acid reactive substance (TEARS) levels in plasma and RBC, and decreased RBC vit E levels. Vit E treatment decreased elevated TEARS levels in plasma and RBC and also increased reduced RBC vit E levels, and prevented RBC membrane destruction and hemolysis. In conclusion, vit E treatment appears to be beneficial in preventing acetone-induced oxidative RBC damage, and therefore, it can improve RBC rheology. © 2005 Springer Daha fazlası Daha az

Özaçmak, Veysel Haktan | Sayan, Hale | Çetin, Alpay | Akyıldız-İğdem, Ayşenur

Article | 2007 | Neurochemical Research32 ( 8 ) , pp.1314 - 1321

One of common pathophysiological states associated with central nervous system is chronic cerebral hypoperfusion (CH) that frequently occurs in conditions such as vascular dementia and Alzheimer's disease. Long term blockage of angiotensin II type 1 (AT 1 ) receptor provides protection from ischemia induced injury of brain as well as reduction of cerebrovascular inflammation. Examining effect of the blockage on reduced glutathione (GSH), ascorbic acid (AA), and lipid peroxidation were of purpose in the present study. Modeling CH, rats were subjected to permanent occlusion of common carotid arteries bilaterally. AT 1 receptor antagon . . .ist, candesartan, was given daily for 14 days after surgery. CH caused a significant increase in lipid peroxidation and decrease in GSH content of cerebral hippocampal tissue with no change in AA level. Candesartan (0.5 mg/kg, oral) not only reduced lipid peroxidation but also restored GSH significantly besides elevating AA and improving histopathological alterations. In conclusion, long term AT 1 receptor blockage may be considered as novel therapeutic approach for protection from damage associated with CH. Underlying mechanism(s) may in part be related to suppressing oxidative stress and preserving brain antioxidant capacity. © 2007 Springer Science+Business Media, LLC Daha fazlası Daha az

Yeşilli, Çetin | Mungan, Görkem | Seçkiner, İlker | Akduman, Bülent | Numanoğlu, Gamze | Mungan, Aydın

Article | 2006 | International Urology and Nephrology38 ( 1 ) , pp.129 - 132

Objective: Previous studies demonstrated that acute in vitro exposure of corpus cavernosal tissue to ethanol decreased its response to field stimulation and pharmacological stimulation. In the present study we investigated the effects of chronic ethanol consumption on the ultrastructure of cavernosal smooth muscle cells, elastic fibres and collagen content. Material and methods: Fourteen adult wistar rats were divided into a control group (n = 7, fed a standard diet and tap water) and an alcoholic group (n = 7, fed a standard diet and 5% (v/v) ethanol in drinking water and by increasing the ethanol concentration for every week, at t . . .he end of 6th week 30% (v/v) ethanol concentration was attained. Same dose was given until 12th week. At the end of 12th week blood samples were obtained and the ethanol concentrations were determined. The cavernosal tissues were obtained and immunohistochemical examinations were performed. Results: Immunohistochemical analysis revealed that chronic ethanol exposure markedly decreased the content of smooth muscle cells, elastic fibres and collagen type 4. Conclusion: Our findings suggest that in this animal model chronic ethanol exposure decreases the percentage of staining for smooth muscle actin, elastin, and collagen type 4 which are the key structures fundamental for erection. © Springer 2006 Daha fazlası Daha az

Çakmaklı, Birten | Hazer, Baki | Tekin, İshak Özel | Açıkgöz, Şerefden | Can, Murat

Article | 2007 | JAOCS, Journal of the American Oil Chemists' Society84 ( 1 ) , pp.73 - 81

To diversify edible-oil polymer composite, polymeric linoleic acid (PLina) peroxide was obtained by the auto-oxidation of linoleic acid in a simple way for use as a macroinitiator in free radical polymerization of vinyl monomers. Peroxidation, epoxidation, and/or perepoxidation reactions of linoleic acid under air at room temperature resulted in PLina, having soluble fraction more than 91 weight percent (wt%), with molecular weight ranging from 1,644 to 2,763 Da, and containing up to 1.0 wt% of peroxide. PLina initiated the free radical polymerization of ether styrene (S), methyl methacrylate (MMA), or n-butyl methacrylate (nBMA) to . . . give PLina-g-polystyrene (PS), PLina-g-poly-MMA (PMMA), and PLina-g-poly- nBMA (PnBMA) graft copolymers. The polymers obtained were characterized by proton nuclear magnetic resonance (1H NMR), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC) techniques. Microstructure of the graft copolymers was observed by using scanning electron microscope (SEM). Graft copolymers obtained contained polymeric linoleic acid in a range between 8.5 and 19.3 mol percent (mol%). PLina-g-PS, PLina-g-PMMA and PLina-g-PnBMA graft copolymer samples were also used in cell culture studies. Fibroblast and macrophage cells were strongly adhered and spread on the copolymer film surfaces. These newly synthesized copolymers were tested for their effects on human blood protein adsorption compared with PMMA graft copolymers containing polymeric soybean oil and polymeric linseed oil; interestingly we observed a dramatic decrease in the protein adsorption on the linoleic acid graft copolymer, which is important in tissue engineering. © AOCS 2007 Daha fazlası Daha az

Cömert-Beğendik, Füsun | Cömert, Mustafa | Külah, Canan | Taşçılar, Öge | Numanoğlu, Gamze | Aydemir, Selim

Article | 2006 | DIGESTIVE DISEASES AND SCIENCES51 ( 6 ) , pp.1039 - 1042

3rd European Meeting on Molecular Diagnostics -- 37910 -- Scheveningen, NETHERLANDS WOS: 000239295700002 PubMed: 16865564

Bektaş, Sibel | Karakaya, Kemal | Can, Murat | Bahadır, Buarak | Güven, Berrak | Erdoğan, Nilsen | Özdamar, Şükrü Oğuz

Article | 2016 | Kaohsiung Journal of Medical Sciences32 ( 7 ) , pp.339 - 347

The aim of this study was to investigate the effects of tadalafil (TDF) and pentoxifylline (PTX) on hepatic apoptosis and the expressions of endothelial and inducible nitric oxide synthases (eNOS and iNOS) after liver ischemia/reperfusion (IR). Forty Wistar albino rats were randomly divided into five groups (n = 8) as follows: sham group; IR group with ischemia/reperfusion alone; low-dose and high-dose TDF groups received 2.5 mg/kg and 10 mg/kg TDF, respectively; and PTX group received 40 mg/kg PTX. Blood was collected for the analysis of serum alanine aminotransferase, aspartate aminotransferase, ?-glutamyl transferase, uric acid, . . .malondialdehyde (MDA), and total antioxidant capacity (TAC). MDA and TAC also were measured in liver tissue. Histopathological examination was performed to assess the severity of hepatic injury. Apoptosis was evaluated using the apoptosis protease-activating factor 1 (APAF-1) antibody; the expressions of eNOS and iNOS were also assessed by immunohistochemistry in all groups. Serum alanine aminotransferase, aspartate aminotransferase, ?-glutamyl transferase, uric acid, MDA, and TAC, tissue MDA and TAC levels, hepatic injury, and score for extent and for intensity of eNOS, iNOS, and apoptosis protease-activating factor 1 were significantly different in TDF and PTX groups compared to the IR group. High dose-TDF and PTX have the best protective effect on IR-induced liver tissue damage. This study showed that TDF and PTX supplementation may be helpful in preventing free oxygen radical damage, lipid peroxidation, hepatocyte necrosis, and apoptosis in liver IR injury and minimizing liver damage. © 201 Daha fazlası Daha az