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Öğe Ameliorating effects of quercetin and chrysin on 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced nephrotoxicity in rats(Sage Publications Inc, 2012) Ciftci, Osman; Ozdemir, Ilknur; Vardi, Nigar; Beytur, Ali; Oguz, FatihThe aim of this study is to investigate the beneficial effects of the quercetin (Q) and chrysin (CH) against nephrotoxicity induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a persistent environmental contaminant, in rats. Rats were divided randomly into six equal groups. TCDD, Q and CH were administered by gavages dissolved in corn oil at the doses of 2 mu g/kg/week, 20 mg/kg/day and 50 mg/kg/day, respectively. The kidney samples were taken from all rats on day 60 for the determination of thiobarbituric acid reactive substances (TBARS), glutathione (GSH), catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) levels by spectrophotometric method. The results indicated that TCDD significantly induced lipid peroxidation and reduced antioxidant activities in rats. In contrast, Q and CH significantly prevented toxic effects of TCDD via increased GSH, CAT, GPx and SOD levels but decreased formation of TBARS. Also, it was determined that exposure to TCDD leads to significant histological damage in kidney tissue, and these effects can be eliminated with Q and CH treatment. In conclusion, the current study showed that exposure to TCDD can exert nephrotoxicity in rats. When Q and CH were given together with TCDD, they prevented nephrotoxic effects of TCDD. Their preventive effect lends more support to the role of oxidative and histological damage in the overall toxicity of TCDD.Öğe Amine-fnctionalized silver and gold N-heterocyclic carbene complexes: Synthesis, characterization and antitumor properties(Elsevier Science Sa, 2019) Kizrak, Umran; Ciftci, Osman; Ozdemir, Ilknur; Gurbuz, Nevin; Dusunceli, Serpil Demir; Kaloglu, Murat; Mansour, LamjedDiisopropilamine-tethered benzimidazolium salts have been prepared as precursors for Ag(I)-NHC and Au(I)-NHC complexes. These NHC ligands were metallated with Ag2O on moderate conditions to give novel silver-NHC complexes. Gold-NHC complexes have been obtained by transmetalation using the silver-NHC precursor. The structures of all compounds were characterized by H-1 NMR, C-13 NMR, IR and elemental analysis techniques. The cytotoxic properties of the silver(I) and gold(I) complexes have been assessed in various human cancer lines, including cisplatin-sensitive and resistant cell. IC50 values of these four complexes were determined by the MTS based assay on three human cancer cell lines (SHSY5Y, HTC116 and HEP3B) and human healthy cell line (HF). These silver and gold N-heterocyclic carbene complexes have been highlighted metal-based cancer therapeutic agent with unique structures and functions. These strategies provide exciting opportunities for discovering new type metalodrug. (C) 2019 Elsevier B.V. All rights reserved.Öğe Antimicrobial activities of bis-(N-alkylbenzimidazole)-cobalt(II) and zinc (II) complexes(Elsevier, 2023) Sahin, Neslihan; Ustuen, Elvan; Ozdemir, Ilknur; Gunal, Selami; Ozdemir, Namik; Bulbul, Hakan; Gurbuz, NevinEight benzimidazole precursors (L), namely 1-allyl-benzimidazole, 1-methallyl-benzimidazole, 1-isopropyl-benzimidazole, 1-(3-methyloxetan-3-yl)methyl-benzimidazole, 1-allyl-5,6-dimethyl-benzimidazole, 1-methallyl-5,6dimethyl-benzimidazole, 1-isopropyl-5,6-dimethyl-benzimidazole and 1-(3-methyloxetan-3-yl)methyl-5,6dimethyl-benzimidazole, were coordinated to cobalt(II) and zinc(II) cations to form complexes of the type [MCl2L2]. Single-crystal X-ray structures were determined for two cobalt(II) and for one zinc(II) complexes and confirmed their tetrahedral molecular geometry. The antibacterial and antifungal activities of these two series of cobalt(II) and zinc(II) complexes were studied against Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae), Gram-positive (Staphylococcus aureus, methicillin-resistant S. aureus and Enterococcus faecalis) bacteria and fungal strains (Candida albicans and Candida glabrata). Overall, cobalt(II) complexes were more effective than the zinc(II) complexes against all microorganisms. The most significant results were obtained with the two dichloro-bis(1-allyl-5,6-dimethylbenzimidazole)-cobalt(II) and dichloro-bis(1-methallyl-5,6-dimethylbenzimidazole)-cobalt(II) complexes against Candida albicans and Candida glabrata fungi with measured minimal inhibitory concentrations as low as 0.024 mu mol/mL, values close to those obtained with the commercially available drug Flucanozole (0.020 mu mol/mL).Öğe Antioxidant Effect of Ethanolic Extract of Propolis in Liver of L-NAME Treated Rats(Wroclaw Medical Univ, 2015) Selamoglu, Zeliha S.; Ozdemir, Ilknur; Ciftci, Osman; Gulhan, Mehmet F.; Savci, AhmetBackground. The blocking of nitric oxide synthase (NOS) activity may cause vasoconstriction with formation of reactive oxygen species. Propolis is a natural product collected from plants by honeybees. Propolis has biological and pharmacological properties. Objectives. This study was designed to investigate the effects of propolis on catalase (CAT) activity, nitric oxide (NO) and malondialdehyde (MDA) levels in the liver tissues of NOS inhibited rats by N omega-Nitro-L-arginine methyl ester (L-NAME). Material and Methods. Rats were given a NOS inhibitor (L-NAME, 40 mg/kg, intraperitoneally) for 15 days to provoke hypertension and propolis (200 mg/kg, by gavage) the last 5 of the 15 days. Results. Nitric oxide levels in the liver tissue of the rats given L-NAME significantly decreased (p < 0.01). That parameter did not significantly alter in the liver of rats treated with propolis compared to the control group. CAT activity and MDA levels in the liver of the rats administrated L-NAME significantly increased compared to the control group (p < 0.01). These parameters significantly decreased in the liver of the rats given L-NAME + propolis compared to the L-NAME group (p < 0.01). Conclusions. The present data shows that L-NAME in the liver may enhance oxidative stress via inhibited nitric oxide synthase. Our results also suggest that this effect is suppressed by the antioxidant properties of propolis in the liver tissue of NOS inhibited ratsÖğe Antioxidative effects of curcumin, ?-myrcene and 1,8-cineole against 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced oxidative stress in rats liver(Sage Publications Inc, 2011) Ciftci, Osman; Ozdemir, Ilknur; Tanyildizi, Sadettin; Yildiz, Sedat; Oguzturk, HakanThe aim of this study was to investigate the effectiveness of curcumin, beta-myrcene (myrcene) and 1,8-cineole (cineole) on antioxidant defense system in rats given a persistent environmental pollutant (2,3,7,8-tetrachlorodibenzo-p-dioxin, TCDD). Rats (n = 112) were divided randomly into 8 equal groups. One group was kept as control and given corn oil as carrier. TCDD was orally administered at the dose of 2 mu g/kg/week. Curcumin, myrcene and cineole were orally administered at the doses of 100 mg/kg/day, 200 mg/kg/day and 100 mg/kg/day, respectively, by gavages dissolved in corn oil with and without TCDD. The liver samples were taken from half of all rats on day 30 and from the remaining half on day 60 for the determination of thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), catalase (CAT), glutathione peroxidase (GSH-Px) and CuZn-SOD levels by spectrophotometric method. The results indicated that although TCDD significantly (p <= 0.01) increased formation of TBARS, it caused a significant decline in the levels of GSH, CAT, GSH-Px and CuZn-SOD in rats. In contrast, curcumin, myrcene and cineole significantly increased GSH, CAT, GSH-Px and CuZn-SOD levels but decreased formation of TBARS. Additionally, the antioxidative effects of curcumin, myrcene and cineole were increased at day 60 compared to day 30. In the TCDD groups given curcumin, myrcene and cineole, oxidative stress decreased by time. In conclusion, curcumin, myrcene and cineole showed antioxidant activity and eliminated TCDD-induced oxidative stress in rats in a time-dependent manner.Öğe Antioxidative effects of novel synthetic organoselenium compound in rat lung and kidney(Academic Press Inc Elsevier Science, 2009) Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Yilmaz, Ismet; Gok, YetkinThe effects of environmental chemicals, drugs, and physical agents on the developing lung and kidney are influenced by the state of development and maturation. Selenium is an essential element with physiological nonenzymatic antioxidant properties. Therefore, we undertook the present study to evaluate the antioxidant potential of the novel synthetic organoselenium compounds (Se I and Se II). In this study, adult female Wistar rats were treated with DMBA and the novel organoselenium compounds [1-isopropyl-3-methylbenzimidazole-2-selenone (Se I) and 1,3-di-p-methoxybenzylpyrimidine-2-selenone (Se II)] in the determined doses. The protective effects of novel synthetic organoselenium compounds (Se I and Se II) against DMBA-induced changes in levels of some [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) activities and total glutathione (GSH), malonedialdehyde (MDA)] parameters in rat lung and kidney were investigated. As a result, it was found that both Se I and Se II had provided the antioxidant effects against DMBA-induced oxidative stress in rat lung and kidney and lipid peroxidation had also been decreased by these organoselenium compounds. (c) 2007 Elsevier Inc. All rights reserved.Öğe Antioxidative role of selenium against the toxic effect of heavy metals (Cd+2 Cr+3 on liver of rainbow trout (Oncorhynchus mykiss Walbaum 1792)(Springer, 2008) Talas, Zeliha Selamoglu; Orun, Ibrahim; Ozdemir, Ilknur; Erdogan, Kenan; Alkan, Aysel; Yilmaz, IsmetThe main purpose of this study is to discuss the effect of Cd+2, Cr+3 and Se metals on biochemical parameters in liver tissue of Oncorhynchus mykiss. The rainbow trout were exposed to heavy metal stress ( Cd+2, Cr+3) at 2 ppm dosage. The present study was undertaken to determine the protective effect of selenium treatment at the same dosage ( 2 ppm) on some biochemical parameters. The activity of catalase ( CAT), glutathione peroxidase ( GSH-Px), superoxide dismutase ( SOD) and the changes in levels of malondialdehyde ( MDA) from biochemical parameters were determined in liver tissue of the fish groups exposed to heavy metals, especially for the selenium-applied groups. Results of this study showed that the activities of CAT, GSH-Px and SOD in the tissues of fish exposed to the stress of Cd+2 and Cr+3 were significantly lower than the control groups ( P < 0.05). Meanwhile, the closer values to the control groups were obtained in selenium-added groups ( Cr+3 + Se+4, Cd+2 + Se+4). For the level of MDA, the last production of lipid peroxidation showed increases ( P < 0.05) in the groups exposed to the metal stress, whereas significant decreases were obtained in selenium-applied groups. The result of the statistical evaluation showed that the negative effects occurring in the biochemical parameters of the applied groups exposed to the toxicity of heavy metal were significantly eliminated ( P < 0.05) as a result of selenium treatment.Öğe Benzimidazolium-based novel silver N-heterocyclic carbene complexes: synthesis, characterisation and in vitro antimicrobial activity(Taylor & Francis Ltd, 2016) Sari, Yakup; Akkoc, Senem; Gok, Yetkin; Sifniotis, Vicki; Ozdemir, Ilknur; Gunal, Selami; Kayser, VeyselThis study reports the synthesis, characterisation and antimicrobial activity of five novel silver N-heterocyclic carbene (Ag-NHC) complexes obtained by N-propylphthalimide and N-methyldioxane substituted benzimidazolium salts with silver oxide. The reactions were performed at room temperature for 24 h in the absence of light. The obtained complexes were identified and characterised by H-1 and C-13 NMR, FT-IR and elemental analysis techniques. The minimum inhibitory concentration (MIC) of the complexes was determined for E. coli, P. aeruginosa, E. faecalis, S. aureus, C. tropicalis and C. albicans in vitro through agar and broth dilution. The results indicated that these complexes exhibit antimicrobial activity. In particular, complex 3 presented the significant broad spectrum antimicrobial activity.Öğe CHANGES IN TYROSINE HYDROXYLASE ACTIVITY, ADRENOMEDULLIN (ADM) AND TOTAL RNA LEVELS BY TREATMENT OF ORGANOSELENIUM COMPOUNDS IN RAT HYPOTHALAMUS EXPOSED TO 7,12-DIMETHYLBENZANTHRACENE (DMBA)(Parlar Scientific Publications (P S P), 2010) Ozdemir, Ilknur; Talas, Zeliha Selamoglu; Gok, Yetkin; Ates, Burhan; Yilmaz, IsmetThe effects of synthetic organoselenium compounds (Se I and Se II) on the activity of tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine synthesis as well as adrenomedullin (ADM) and total RNA levels were determined in the hypothalamus of adult rats exposed to DMBA (7,12-dimethylbenz[a]anthracene). DMBA, an organic environmental pollutant, is a polycyclic aromatic hydrocarbon that can induce a range of toxic effects and stress in rats. Selenium is an essential trace element, which interacts with antioxidants, and has anticancer and antihypertensive properties. TH is an aromatic amino acid hydroxylase whose activity is elevated in response to a range of stress inducers. TH activity is normally regulated by negative feedback in catecholamine biosynthesis. ADM is an abundantly present peptide in a broad range of normal tissues including adrenal medulla, lungs, kidneys and brain. Plasma ADM levels are elevated in a number of diseases including essential hyptertension and chronic renal failure. The antioxidant properties of ADM offer protection against organ damage induced by high blood pressure, ischemia and aging. DMBA treatment increased the TH activity and ADM level in the hypothalamus. These increases were found to be inhibited by Se I and Se II treatments. These studies demonstrate that synthetic organoselenium compounds can suppress DMBA-induced stress-related changes in the rat hypothalamus. Therefore, the antioxidant and antihypertensive effects of Se I and Se II may have important effects in the maintainance of homeostasis.Öğe Crystal structure, optical properties, spectroscopic characterization and density functional theory studies of a new rhodium (i)-imidazolidin-2-ylidene complexes: Synthesis, characterization and cytotoxic properties(Elsevier Science Sa, 2022) Karaca, Emine Ozge; Ciftci, Osman; Ozdemir, Ilknur; Karabiyik, Hande; Karabiyik, Hasan; Gurbuz, Nevin; Ozdemir, IsmailRhodium(I) complexes bearing imidazolidin-2-ylidene ligands have been widely used in catalytic chemistry, but there are very few reports of the biological properties of these type complexes. A series of [RhCl(COD)(NHC)] complexes were synthesized. The structures of all compounds were characterized by 1H NMR, 13C NMR, IR and elemental analysis techniques, which supported the proposed structures. The single-crystal structures of complexes 1a and 1c have been determined. Single-crystal X-ray diffraction analysis indicates that complexes 1a and 1c crystallize in the centrosymmetric space groups P n m a and I 1 2/a 1 of the orthorhombic and monoclinic systems respectively. The ground state geometry of these complexes was optimized using density functional theory (DFT) at mixed double zeta basis set, 6-31G(d) for H, C, N, O and Cl and LANL2DZ for Rh. The presence of the different functional groups and the nature of their vibrations were identified by the experimental and theoretical infrared spectra. The optical properties of the studied complex were determined experimentally using UV-visible and photoluminescence techniques in solid-state and theoretically using the TD-DFT method. Hirshfeld surface analysis employing 3D molecular surface contours and 2D fingerprint plots has been used to analyze intermolecular interactions present in the solid-state. The cytotoxic properties of the rhodium(I)-NHC complexes have been assessed in various human cancer lines, including cisplatin-sensitive and resistant cells. IC50 values of these four complexes were determined by the MTS-based assay on three human cancer cell lines; brain (SH-SY5Y), colon (HTC116), and liver (Hep 3B). Substances 1a-d showed 100% anticarcinogenic effect in cancer cell lines at 50 and 100 mu M.Öğe Design, synthesis, antimicrobial activity and molecular docking study of cationic bis-benzimidazole-silver(I) complexes(Wiley-V C H Verlag Gmbh, 2023) Ustun, Elvan; Sahin, Neslihan; Ozdemir, Ilknur; Gunal, Selami; Gurbuez, Nevin; Ozdemir, Ismail; Semeril, DavidTwo series of bis(1-alkylbenzimidazole)silver(I) nitrate and bis(1-alkyl-5,6-dimethylbenzimidazole)silver(I) nitrate complexes, in which the alkyl substituent is either an allyl, a 2-methylallyl, an isopropyl or a 3-methyloxetan-3-yl-methyl chain, were synthesized and fully characterized. The eight N-coordinated silver(I) complexes were screened for both antimicrobial activities against Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii) and Gram-positive (Staphylococcus aureus, Staphylococcus aureus MRSA, and Enterococcus faecalis) bacteria and antifungal activities against Candida albicans and Candida glabrata strains. Moderate minimal inhibitory concentrations (MIC) of 0.087 & mu;mol/mL were found when the Gram-negative and Gram-positive bacteria were treated with the silver complexes. Nevertheless, MIC values of 0.011 & mu;mol/mL, twice lower than for the well-known fluconazole, against the two fungi were measured. In addition, molecular docking was carried out with the structure of Escherichia coli DNA gyrase and CYP51 from the pathogen Candida glabrata with the eight organometallic complexes, and molecular reactivity descriptors were calculated with the density functional theory-based calculation methods.Öğe The determination of oxidative damage in heart tissue of rats caused by ruthenium(II) and gold(I) N-heterocyclic carbene complexes(Sage Publications Inc, 2011) Ciftci, Osman; Ozdemir, Ilknur; Cakir, Oguz; Demir, SerpilIn the present study, we aimed to determine the oxidative damage in rat heart tissue induced by ruthenium(II)-NHC (Ru) and gold(I)-NHC (Au) complexes which have anticarcinogenic effects and not used clinically yet. For this purpose, 35 Sprague-Dawley ratswere randomly divided into 5 equal groups. In the control group, rats treated with saline, Ru and Au complexes were intraperitoneally given high (10 mg/kg) and low (5 mg/kg) doses as only one administration. The animals were killed, and heart tissues were taken on day 10 of the drug administration for the determination of the biochemical parameters (malondialdehyde, superoxide dismutase, reduced glutathione and catalase levels). It was determined that both Ru and Au complexes treatment significantly caused oxidative damage compared to the control group. Additionally, it was shown that Au treatment causedmore adverse effects than Ru treatment. Also, it was clearly found that the occurred effects were generally determined in a dose-dependent manner. In conclusion, when these compounds synthesized for the treatment of cancer were used, they caused oxidative damage in heart tissue. However, Ru complex could be preferred for cancer treatment in terms of user safety.Öğe Effects of Quercetin and Chrysin on 2,3,7,8-Tetrachlorodibenzo-p-dioxin Induced Hepatotoxicity in Rats(Wiley, 2013) Ciftci, Osman; Vardi, Nigar; Ozdemir, IlknurThe objective of current study is to investigate the effects of the administration of chrysin (CH) and quercetin (Q) on rat liver in which oxidative and histological damage had been induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Rats were randomly divided into six equal groups. TCDD was orally administered at the dose of 2 mu g/kg/week, and Q and CH were orally administered at the doses of 20 mg/kg day and 50 mg/kg/day, respectively, by gavages dissolved in corn oil. The liver samples to be analyzed for the determination of oxidative and histological alternations were taken from rats at 60 days. The results indicated that although 2,3,7,8-TCDD significantly induced (P <= 0.01) lipid peroxidation (increase of MDA levels), it positively affected oxidant/antioxidant system (a decline in the levels of GSH, CAT, GSH-Px, and CuZn-SOD) in rats significantly. The histological changes observed in the liver correlated with the biochemical findings. However, these effects of TCDD on oxidative and histological changes were eliminated by Q and CH treatment. In conclusion, TCDD caused an adverse effect on rat's liver. When Q and CH were given together with TCDD, they prevented hepatotoxicty induced by TCDD. Thus, it is thought that Q and CH may be useful as a new category of anti-TCDD toxicity agent. (C) 2011 Wiley Periodicals, Inc.Öğe The effects of synthetic organoselenium compounds on nitric oxide in DMBA - induced rat liver(Triveni Enterprises, 2009) Talas, Zeliha Selamoglu; Bayraktar, Nihayet; Ozdemir, Ilknur; Gok, Yetkin; Yilmaz, IsmetDMBA (7,12-dimethylbenz[a]anthracene) is known to generate DNA-reactive species during their metabolism, which may enhance oxidative stress in cells. Since selenium is known as a non-enzymic antioxidant, health problems induced by many environmental pollutants, have stimulated the evaluation of relative antioxidant potential of selenium and synthetic organoselenium compounds. Therefore, we aimed to evaluate chemopreventive potential of synthetic organoselenium compounds by monitoring level of liver nitric oxide. In this study, adult female Wistar rats were treated with DMBA and the novel organoselenium compounds (Se I) and (Se II) in the determined doses. DMBA-induced in rats, the effects of organoselenium compounds on nitric oxide levels in rat liver was studied. In this study, it has been observed a statistically significant increase in (Nitric Oxide) levels for the liver of rat exposed to DMBA (p<0.05). However with administration of Se I and Se II there was a statistically significant decrease in NO levels (p<0.05). The ability of the organoselenium compounds to prevent oxidative damage induced by DMBA in rat livers was rationalized. Protection against nitric oxide measured in Se I and Sell treated groups were provided by synthesized organoselenium compounds. Se I and Sell both provided chemoprevention against DMBA-induced oxidative stress in rat liver.Öğe Gold(I) Complexes of N-Heterocyclic Carbene Ligands Containing Benzimidazole: Synthesis and Antimicrobial Activity(Mdpi, 2010) Ozdemir, Ilknur; Temelli, Nazan; Gunal, Selami; Demir, SerpilGold(I) N-heterocyclic carbene (NHC) complexes were obtained in good yields from the corresponding silver complexes by treatment with [AuCl(PPh3)] following the commonly used silver carbene transfer route. The silver complexes were synthesized from the benzimidazolium halide salts by the in situ reactions with Ag2O in dichloromethane as a solvent at room temperature. All gold complexes have been characterized by H-1-NMR, C-13-NMR and IR spectroscopy and elemental analysis. Au-NHC complexes were evaluated for their in vitro antimicrobial activity against a variety of Gram-positive and Gram-negative bacteria and fungal species.Öğe In vitro antimicrobial studies of naphthalen-1-ylmethyl substituted silver N-heterocyclic carbene complexes(Elsevier, 2019) Gok, Yetkin; Akkoc, Senem; Celikal, Ozlem Ozeroglu; Ozdemir, Ilknur; Gunal, SelamiSeven novel naphthalen-1-ylmethyl substituted silver N-heterocyclic carbene (Ag-NHC) complexes (1-7) were synthesized by the interaction of benzimidazolium salts with silver carbonate in dry dichloromethane at room temperature and characterized by means of spectroscopic methods and elemental analysis techniques. The Ag-NHC compounds were tested for their in vitro antibacterial and antifungal activity against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Candida albicans and Candida tropicalis and showed high antimicrobial activities. The synthesized complexes, in particular, demonstrated better results against both fungi and gram-positive bacteria. (C) 2015 The Authors. Published by Elsevier B.V. on behalf of King Saud University.Öğe The investigation of the antioxidative properties of the novel synthetic organoselenium compounds in some rat tissues(Sage Publications Ltd, 2008) Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Yilmaz, Ismet; Gok, Yetkin; Orun, IbrahimDMBA (7,12-dimethylbenz[a]anthracene) is a polycyclic aromatic hydrocarbon (PAH) known to cause tumors in rats. Selenium is an essential element with physiological nonenzymatic antioxidant properties. Because of the health problems induced by many environmental pollutants, many efforts have been undertaken in evaluating the relative antioxidant potential of selenium and synthetic organoselenium compounds. In this study, adult female Wistar rats were treated with DMBA and the novel organoselenium compounds (1-isopropyl-3-methylbenzimidazole-2-selenone [Sel] and 1,3di-p-methoxybenzylpyrimidine-2-selenone [Sell]) in the determined doses. The protective effects of novel synthetic organoselenium compounds (Sel and Sell) against DMBA-induced changes in superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) activities and total glutathione (GSH) and malonedialdehyde (MDA) levels of rat heart and brain were investigated. It was determined that Sel and Sell fully or partially restored enzyme activity. It was also found that lipid peroxidation was also decreased in Sel and Sell treated groups. Consequently, it was determined that novel synthetic organoselenium compounds (Sel and Sell) provided protection of antioxidant activity, and protection against lipid peroxidation measured as MDA in Sel and Sell treated groups was provided by novel synthesized organoselenium compounds. The ability of the organoselenium compounds to prevent oxidative damage induced by DMBA in rats was rationalized.Öğe Modulating effects of selenium in adrenal medulla of rats exposed to 7,12-dimethylbenz[a]anthracene(Sage Publications Inc, 2013) Talas, Zeliha Selamoglu; Ozdemir, Ilknur; Ates, Burhan; Gok, Yetkin; Yilmaz, IsmetObjective: The aim of this study was to evaluate the chemopreventive potential of organoselenium compounds (Se I and Se II) in the well-established rat model treated with 7,12-dimethylbenz[a]anthracene (DMBA), by monitoring the extent of tyrosine hydroxylase (TH) activity, adrenomedullin (ADM) level and total RNA level in adrenal medulla. Organic pollutants are the most important environmental factor for the biologic systems. DMBA exposure appears to be associated with a number of physiological disease processes. Methods: The effects of Se I and Se II compounds were investigated on TH activity, ADM and total RNA levels in adrenal medulla of rats exposed to DMBA. Results: TH activity, ADM and total RNA levels were found to be increased significantly due to the effect of DMBA (p < 0.05). This increase was restricted in the Se I-and Se II-treated groups (p < 0.05). Conclusion: The present data showed that the organoselenium compounds may have important effects in the maintainance of homeostasis against stress induced by DMBA.Öğe N-functionalized benzimidazol-2-ylidene silver complexes: synthesis, characterization, and antimicrobial studies(Tubitak Scientific & Technological Research Council Turkey, 2013) Gok, Yetkin; Akkoc, Senem; Ozeroglu Celikal, Ozlem; Ozdemir, Ilknur; Gunal, Selami; Sayin, Elif2-Methoxyethyl, 2-diethylaminoethyl, and 2-phenylethyl-substituted N-heterocyclic carbene (NHC) precursors were treated with Ag2CO3 to yield silver(I)-NHC complexes (1a-g) in dichloromethane as a solvent at room temperature. The 7 new silver-NHC complexes were fully characterized by means of H-1 NMR, C-13 NMR, and elemental analysis techniques. Using the agar dilution procedure recommended by the Laboratory and Clinical Standards Institute, the antimicrobial activities of all the silver-NHC complexes were studied against 2 gram-negative bacterial strains (Pseudomonas aeruginosa and Escherichia coli), 2 gram-positive bacterial strains (Enterococcus faecalis and Staphylococcus aureus), and 2 fungi (Candida tropicalis and Candida albicans).Öğe Novel benzimidazol-2-ylidene carbene precursors and their silver(I) complexes: Potential antimicrobial agents(Pergamon-Elsevier Science Ltd, 2016) Kaloglu, Murat; Kaloglu, Nazan; Ozdemir, Ilknur; Gunal, Selami; Ozdemir, IsmailNovel benzimidazolium salts were synthesized as N-heterocyclic carbene (NHC) precursors, these NHC precursors were metallated with Ag2O in dichloromethane at room temperature to give novel silver (I)-NHC complexes. Structures of these benzimidazolium salts and silver(I)-NHC complexes were characterized on the basis of elemental analysis, H-1 NMR, C-13 NMR, IR and LC-MS spectroscopic techniques. A series of benzimidazolium salts and silver(I)-NHC complexes were tested against standard bacterial strains: Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and the fungal strains: Candida albicans and Candida tropicalis. The results showed that benzimidazolium salts inhibited the growth of all bacteria and fungi strains and all silver(I)-NHC complexes performed good activities against different microorganisms. (C) 2016 Elsevier Ltd. All rights reserved.
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