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Publication Metadata only 1,2,3-Triazole incorporated coumarin carrying metal-free, Zn(II), Mg(II) phthalocyanines: Synthesis, characterization, theoretical studies, photophysical and photochemical properties(ELSEVIER SCIENCE SA, 2020) YALÇIN, BAHATTİN; Ozdemir, Mucahit; Abliatipova, Aziza; Benian, Sueda; Yalcin, Bahattin; Salan, Umit; Durmus, Mahmut; Bulut, MustafaIn this study, the preparation of two novel phthalonitrile compounds, 7-(propargyloxy)-3-(3,4-dicyanophenoxyphenyl)coumarin (1), and 7-(propargyloxy)-3-(2,3-dicyanophenoxy-phenyl)coumarin (2) were performed. Two new coumarinyl-1,2,3-triazole hybrids, (1-phenethy1-1H41,2,A-triazole 4 yl) 7 methyleneoxy 3 [F. (3,4 dicya nophenoxy)phenyl]-coumarin (3), and (1-phenethy1-1H-[1,2,3]-triazole 4 yl) 7 methyleneoxy 3 [F. (2,3 dicya nophenoxy)phenyl]-coumarin (4), were synthesized by the copper(I)-catalysed Huisgen 1,3-dipolar cycloaddition reaction of 2-(azidoethyl)benzene with terminal ethynyl bearing coumarin derivatives (1 or 2). These novel phthalonitrile derivatives (3 and 4) were converted into their peripheral (5-7) and non-peripheral (8-10) metal-free, zinc(II) and magnesium(II) phthalocyanine counterparts. The synthesized phthalocyanine derivatives are first examples on the phthalocyanine-coumarin derivatives bearing triazole ring. The structures of all these novel compounds were characterized by variety of spectroscopic techniques including FT-IR, UV-vis, H-1 NMR, MALDI-TOF MS and elemental analysis. The photophysicochemical properties of all studied Pcs (5-10) were determined in dimethyl sulfoxide. The zinc(II) and magnesium(II) phthalocyanines bearing triazole containing coumarin substituents appear to be useful as Type II photosensitizers because the singlet oxygen quantum yields ranged in acceptable values from 0.17 to 0.49 confirmed that these phthalocyanines can be suggested as photosensitizers in Photodynamic Therapy applications. Geometry optimization, frequency analysis and molecular orbital energy values of coumarin/triazole substituted phthalocyanine were performed in Density Functional Theory method using the B3LYP/LANL2DZ level of theory.Publication Metadata only 1,2,4-triazole-5(4H)-one based novel peripherally tetrasubstituted metal-free and metallophthalocyanines: Synthesis, characterization, and electrochemical and spectroelectrochemical properties(TAYLOR & FRANCIS INC, 2017) KOCA, ATIF; Aktas, Ayse; Uenlueer, Dilek; Kobak, Rabia Zeynep Uslu; Acar, Irfan; Dugdu, Esra; Koca, Atif; Kantekin, HalitIn this study, the synthesis of metal-free and metallophthalocyanines containing four 4-[2-(4-methoxyphenyl) ethyl]-5-methyl-2,4-dihydro-3H-1,2,4-triazol-3-one substituents at the peripheral positions were reported. The structures of compounds were characterized using IR, H-1 NMR, C-13 NMR, mass spectroscopies, and UV-Vis. Electrochemistry of the complexes were studied with voltammetric and in situ spectroelectrochemical measurements in different electrolytic systems. MPcs having redox inactive metal centers (H+, Zn+2, Cu+2, and Ni+2) just illustrated similar Pc-based electron transfer reactions. Due to the different effective nuclear charge of the ions in the core of Pc ring, small potential shifts and reversibility differences were observed between the redox processes of these complexes. MPcs having redox-active metal centers (Co+2 and TiO+2) gave metal-based electron transfers in addition to Pc-based processes. Electrolyte type of the measurement system significantly influenced oxidation behaviors of CoPc due to the coordination of polar coordinating solvent molecules to the oxidized Co-III center of CoPc. Spectra and color of the electrogenerated MPc species were determined with in situ spectroelectrochemical measurements.Publication Metadata only 1,3,4-thiadiazole derivatives. Synthesis, structure elucidation, and structure-antituberculosis activity relationship investigation(AMER CHEMICAL SOC, 2004) Oruc, EE; Rollas, S; Kandemirli, F; Shvets, N; Dimoglo, ASA series of 2,5-disubstituted-1,3,4-thiadiazoles were synthesized, the compounds structures were elucidated and screened for the antituberculosis activity against Mycobacterium tuberculosis H37Rv using the BACTEC 460 radiometric system. Among the tested compounds, 2-phenylamino-5-(4-fluorophenyl)-1,3,4-thiadiazole 22 showed the highest inhibitory activity. The relationships between the structures of compounds and their antituberculosis activity were investigated by the Electronic-Topological Method (ETM) and feed forward neural networks (FFNNs) trained with the back-propagation algorithm. As a result of the approach, a system of pharmacophores and anti-pharmacophores has been found that effectively separates compounds of the examination set into groups of active and inactive compounds. The system can be applied to the screening and design of new active compounds possessing skeletons similar to those used in the present study.Publication Metadata only 1,4-Dithiaheterocycle-fused porphyrazines: Synthesis, characterization, voltammetric and spectroelectrochemical properties(ELSEVIER SCI LTD, 2009) KOCA, ATIF; Tuncer, Serap; Koca, Atif; Guel, Ahmet; Avciata, UlviPorphyrazines (M = H, Mg, Zn and Co) with a 2,3-dicyano-5-phenyl-5,6-dihydro-1,4-dithiin group fused to each pyrrole unit were synthesized and characterized starting with the corresponding unsaturated dicarbonitrile derivative. The voltammetric and spectroelectrochemical characterizations of the metallo-porphyrazines (M=2H(+), Mg2+, Zn2+ and Co2+) substituted with 2,3-dicyano-5-phenyl-5,6-dihydro-1,4-dithiin groups on peripheral positions are described. Cyclic voltammetry and differential pulse voltammetry studies showed that while metal-free, magnesium, and zinc porphyrazines represented well-defined one-electron ligand-based reductions and ligand-based one-electron oxidation couples, cobalt porphyrazine gave both metal-based and ligand-based reduction and oxidation couples. Assignments of the redox couples were confirmed by spectroelectrochemical measurements. (C) 2008 Elsevier Ltd. All rights reserved.Publication Metadata only 1-ACETYLHYDROQUINONE 4-GALACTOSIDE FROM FERULAGO-AUCHERI(PERGAMON-ELSEVIER SCIENCE LTD, 1991) DOGANCA, S; ULUBELEN, A; TUZLACI, EFrom the chloroform extracts of the aerial parts of Ferulago aucheri two coumarins osthenol, prantschimgin (marmesin senecioate), two flavonoids isorhamnetin 3-galactoside, 6-hydroxyapigenin 6-methyl ether and two new aromatic compounds 1-acetylhydroquinone 4-galactoside and quinol monoacetate were isolated. The structures were established by spectral and chemical methods.Publication Metadata only 17 beta-estradiol increases intracellular free calcium concentrations of human vascular endothelial cells and modulates its responses to acetylcholine(INFORMA HEALTHCARE, 1997) Moini, H; Bilsel, S; Bekdemir, T; Emerk, KIn this study, we have investigated the effect of (17)beta-estradiol (E2) on intracellular free calcium concentrations ([Ca2+](i)) in human umbilical vein endothelial cells (HUVEC) using fura-2 fluorescence, E2 at concentrations of 1nM-1 mu M was added subsequently to HUVEC cultures which were either deprived of estrogens or preincubated with E2 (100 nM) for 23 hours, In both groups of cultures, E2 stimulated significant increases in [Ca2+](i) in a dose-dependent manner, The effects were more prominent in E2-deprived cells, Preincubation of cells with tamoxifen or the presence of it in the buffer during the experiments did not inhibit the response of the cells to E2, Experiments performed in Ca2+ free/EGTA buffer yielded transient increases in [Ca2+](i) suggesting release of Ca2+ from intracellular stores was responsible for the initial peak, while sustained elevations were supported by Ca2+ influx from the extracellular space, Addition of La3+ abolished the sustained [Ca2+](i) elevations, Carbachol (CCh) (1nM, 100 nM) did not induce changes in [Ca2+](i) of estrogen-deprived cells but produced significant increases in [Ca2+](i) of the same cells after incubation with E2 for 30 minutes, The cultures which were preincubated with E2 for 24 hours responded to carbachol directly, The results of our study indicate that E2 may modulate the functions of endothelial cells after only a brief exposure and also may be necessary for the response to acetylcholine especially at low concentrations.Publication Open Access 17 beta-estradiol modulates endothelin-1 expression and release in human endothelial cells(ELSEVIER SCIENCE BV, 2000-06) Bilsel, AS; Moini, H; Tetik, E; Aksungar, F; Kaynak, B; Ozer, AObjective: In this study the role of 17 beta-estradiol (E2) in the regulation of endothelin-1 (ET-1) mRNA expression and secretion was investigated in cultured human umbilical vein endothelial cells (HUVECs). Methods: Endothelial cells were either deprived of or treated with 17 beta-estradiol (10(-9), 10(-7) M) for 48 h. After the incubation, the effect of E2 on ET-1 gene expression was evaluated by Northern blot analysis. ET-1 release into the media was measured by radioimmunoassay after 6 h of incubation under basal conditions and upon stimulation with thrombin (4 U/ml). In addition, the cyclic guanosine 5'-monophosphate (cGMP) content of cells was assayed by immunoassay. In order to exclude the role of nitric oxide (NO) in E2-induced effects on endothelin-1 gene expression and secretion, nitric oxide synthase (NOS) inhibitor, N-nitro L-arginine methyl ester (1 mM) (L-NAME) was added to the media of some cultures. Results: Incubation of HUVECs with 10(-9) and 10(-7) M E2 for 48 h resulted in a 30 and 47% inhibition of ET-1 mRNA expression, respectively. Incubation with E2 also decreased the basal and thrombin-stimulated ET-1 release while increasing the cGMP content of cells significantly. NOS inhibitor L-NAME increased the release of ET-1 from E2-incubated cells but did not alter the ET-1 release from hormone-deprived cells. However, ET-1 secretion of E2-treated cells were significantly less than the deprived ones. Northern blot analyses also demonstrated that inhibition of NOS only partly attenuated the effect of E2 on ET-1 gene expression. In the presence of L-NAME, treatment with 10(-7) M E2 caused a 12% decrease in ET-1 gene expression. Conclusion: The results demonstrate that E2 may play both direct and indirect role in regulation of ET-1 gene expression and production in human endothelial cells. E2-induced increase in NO but decrease in ET-1 production may partly explain the mechanism of the protective effects of the hormone on the cardiovascular system. (C) 2000 Elsevier Science B.V. All rights reserved.Publication Metadata only 17-β-estradiol increases cytosolic free calcium concentrations ([Ca2+]i) of endothelial cells and modulates the responses to acetylchoune(1996) Bilsel A.S., Moini H., Bekdemir T., Emerk K.In this study, acute effects of E2 addition on ([Ca2+)i) of human umblical vein endothelial cell (HUVEC) cultures were measured by fura-2 fluorescence. E2 was added subsequently at 10-9-10-6M concentrations to HUVEC cultures, which were either deprived of eslrogens or preincubated with E2 for 24 h. In both groups of cultures E2 stimulated dose dependent significant increases in [Ca2+]i at concentrations 10-9-10-6M with the means 48.2, 76.2, 120.0, 129.4% in E2 deprived group and 28.1, 43.9, 56.7, 58.9% in E2 preincubated group, compared to basal levels. Incubation of cells with tamoxifen did not effect the response to E2. Performing experiments in Ca2+ free/EGTA buffer yielded transient increases in [Ca2+]i suggesting release of Ca2+ from intracellular stores first. Inhibition of the influx pathway by addition of La3+ at the peak of the Ca2+ response immediately reduced [Ca2+], to basal levels. Addition of carbachol (10°, 107M) to cultures deprived of estrogens did not induce increases in [Ca2+], but after incubation of the same cultures with E2 for 30 min., carbachol addition caused significant increases in [Ca2+]i with the means 56.9, 93.4% compared to basal levels respectively, while cultures which were incubated with E2 for 24 h responded to carbachol directly in similiar amounts. Results of the study show that E2 may modulate the functions of endothelial cells directly in short time and also indicate that E2 may be necessary for the response to acetylcholine especially at low concentrations and may explain the mechanism of acute E2 effects in potentiation of endothelium dependent vasodilation in response to acetylcholine.Publication Open Access -174 G/C polymorphism of interleukin 6 gene is not significantly different in Turkish professional short and long distance runners(C M B ASSOC, 2018-08-30) Arica, Secil; Solgun, Huscyin Avni; Dengi, Ayse Seda Demirel; Bakmaz, Enver; Akcays, Teoman; Kapici, Sezgin; Sercan, Canan; Ulucan, KorkutInterleukin-6 (IL-6) is a kind of multifunctional cytokine and involved in mediating muscle repair metabolism, and therefore athletic capacity. Muscular and circulating IL-6 levels increase in response to physical exercise. Responsible gene coding for IL-6 has a functional polymorphism in its promoter region, -174 G/C (rs1800795). We aimed to analyze the association of G allele and GG genotype in Turkish professional athletes and compare the allelic and genotypic difference between short distance and long distance runners. For this purpose, we enrolled 40 (24 short distance runners and 16 long distance runners) Turkish professional athletes to the study. Real time genotyping procedure was carried out to determine the -174 G/C polymorphism. G allele and GG genotype was more prevalent than the others in our cohort. We found no statistically significant difference between short and long distance runners in the terms of genotype (p-0.07). Our study suggests that-174 G/C polymorphism of IL-6 gene differs in athletes, G allele and GG genotype is higher than the other ones, at least in Turkish athletes. and therefore should be taken into consideration when determining genetic aspects of athletes. Further studies arc necessary to confirm our results and show the effect of the given polymorphism in sports science.Publication Open Access 18 F-FDG PET/CT imaging of a Grade 3 lymphomatoid granulomatosis in an immunocompromised pediatric patient(2023-02-01) KESİM, SELİN; ÖZGÜVEN, SALİH; ÖNEŞ, TUNÇ; KESİM S., Şen F., ÖZGÜVEN S., ÖNEŞ T.Lymphomatoid granulomatosis is a rare extranodal Epstein-Barr virus-driven B-cell lymphoproliferative disease, involving predominantly lung, less often skin, kidney, and central nervous system. Here, we present a pediatric case with primary immunodeficiency, diagnosed with pathologically proven pulmonary grade-III lymphomatoid granulomatosis.18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging demonstrated18F-FDG avid pulmonary masses with central air-bronchograms and cavitations. Although the definitive diagnosis depends on biopsy,18F-FDG PET/CT serves as a complementary imaging tool to evaluate the extent of the disease and response to treatment.Publication Open Access Publication Metadata only 1:1 binary complexes of citric acid with some metal ions: Stability and thermodynamic parameters(Freund Publishing House Ltd, 2007) Bastuǧ A.S., Göktürk S., Şişmanoǧlu T.The stability constants of the 1:1 binary complexes of citric acid with Cu2+, Ni2+, Co2+, Mn2+ and Ce 3+ were determined potentiometrically at 15.0, 25.0, and 35.0°C and at an ionic strength of 0.10 mol L-1 (NaClO4). UV-VIS spectroscopic studies were also performed in order to confirm the complexes formation and the stability constants of Cu-citric acid system determined potentiometrically. The thermodynamic parameters, ΔG°, ΔH°, and ΔS° were reported for the complexes formation reactions. The enthalpy and entropy changes of all binary complexes are positive.Publication Metadata only 1[p-(Benzoylamino)benzoyl]-4-substituted thiosemicarbazides: Synthesis and antibacterial and antifungal activities(1992) Kalyoncuoglu N., Rollas S., Sur-Altiner D., Yegenoglu Y., Ang O.[No abstract available]Publication Metadata only (2, J)-IDEALS IN COMMUTATIVE RINGS(PUBL HOUSE BULGARIAN ACAD SCI, 2020) Yildiz, Eda; Tekir, Unsal; Koc, SuatLet A be a commutative ring with nonzero identity. In this paper, we introduce the concept of (2, J)-ideal as a generalization of J-ideal. A proper ideal P of A is said to be a (2, J)-ideal if whenever abc is an element of P and a, b, c is an element of A, then ab is an element of P or ac is an element of Jac(A) or be is an element of Jac(A). Various examples and characterizations of (2, J)-ideals are given. Also, we study many properties of (2, J)-ideals and use them to characterize certain classes of rings such as quasi-local rings and Artinian rings.Publication Metadata only 2-(3-Acetyloxy-2-naphthyl)-4-acetyl-5-phenyl-1,3,4-oxadiazoline suppresses pentylenetetrazol-induced convulsive and oxidative activity on mice(2003) Şener G., Keyer-Uysal M., Neşe Doǧan H., Rollas S.The aim of the study was to investigate the antioxidant effect of 2-(3-acetyloxy-2-naphthyl)-4-acetyl-5-phenyl-1,3,4-oxadiazoline (OXA) in mice brain and liver. In this study we also compared the antioxidant and anticonvulsive effets of OXA with that of valproat (VPA), an antiepileptic drug. OXA (100 mg.kg-1) and valproat (150 mg.kg-1) were administered i.p. to mice 4 hours and 1 hour respectively prior pentylenetetrazol (PTZ) injection. Animals were sacrificed after tonic and clonic convulsion and brain and liver tissues were immediately removed to analyse for lipid peroxidation (LPO) and glutathione (GSH) levels. Both OXA and VPA significantly decreased LPO levels in brain and liver which were elevated after PTZ administration. PTZ administration caused depletion of GSH in both brain and liver, however OXA and VPA treatment reversed the GSH levels to control. The results indicated that OXA and VPA protected brain and liver tissue against oxidative damage seen at the time of seizures.Publication Open Access 2-(fluorine-18)-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography after breast conserving surgery: Correlation with molecular markers of breast cancer(MEDKNOW PUBLICATIONS & MEDIA PVT LTD, 2016) TUROĞLU, HALİL TURGUT; Ozguven, Salih; Inanir, Sabahat; Turoglu, Halil Turgut; Erdil, Tanju Yusuf; Ugurlu, Mustafa Umit; Gulluoglu, BahadirAim: To investigate the role of 2-(fluorine-18)-fluoro-2-deoxy-D-glucose (F-18-FDG) positron emission tomography/computed tomography (PET/CT) early after breast-conserving surgery (BCS) in patients with breast cancer (BC) and whether we can determine which molecular biomarkers of breast carcinoma put the patients at risk. Materials and Methods: This retrospective study involved 88 patients with histologically proven T1 or T2 BC, who were treated with BCS and underwent F-18-FDG PET/CT study. The correlation between biological markers (estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 [HER2], and Ki-67) of the primary tumor and F-18-FDG PET/CT findings was analyzed. Results: F-18-FDG PET/CT demonstrated the presence of BC disease (locoregional disease [LRD], distant metastases, or contralateral BC) in 26 of 88 patients (29.5%). Regarding immunohistochemical profiles, BC expressing high levels of Ki-67 were associated with an increased percentage of LRD, which was the major recurrence pattern on F-18-FDG PET/CT. Although the BC disease was observed more commonly in patients with HER2 positivity compared to those of HER2 negative, the difference did not reach statistical significance. The patients with T2 tumor or a higher histopathological grade had a higher percentage of BC disease. Conclusions: This study demonstrated that patients with early stage BC treated with BCS have a remarkable risk of the presence of BC even early after surgery, and there was a clinically important relationship between F-18-FDG PET/CT findings and biological markers of BC. These findings suggest that high-risk molecular biomarkers (Ki-67, HER2) can be taken into account in the decision-making the process for both preoperative imaging and planning of the surgical approach.Publication Metadata only 2-absorbing and weakly 2-absorbing elements in multiplicative lattices(TAYLOR & FRANCIS INC, 2014) TEKİR, ÜNSAL; Jayaram, C.; Tekir, Unsal; Yetkin, EceIn this article we study weakly 2-absorbing elements and 2-absorbing elements in C-lattices. Next we characterize C-lattices in which every nonzero proper element is a (weakly) 2-absorbing element. We also establish a new characterization for principal element domains in terms of 2-absorbing elements.Publication Open Access 2-Heteroarylimino-5-arylidene-4-thiazolidinones as a new class of non-nucleoside inhibitors of HCV NS5B polymerase(ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER, 2013-11) TATAR, ESRA; Kucukguzel, Ilkay; Satilmis, Gokhan; Gurukumar, K. R.; Basu, Amartya; Tatar, Esra; Nichols, Daniel B.; Talele, Tanaji T.; Kaushik-Basu, NeerjaHepatitis C virus (HCV) NS5B polymerase is an important and attractive target for the development of anti-HCV drugs. Here we report on the design, synthesis and evaluation of twenty-four novel allosteric inhibitors bearing the 4-thiazolidinone scaffold as inhibitors of HCV NS5B polymerase. Eleven compounds tested were found to inhibit HCV NS5B with IC50 values ranging between 19.8 and 64.9 RM. Compound 24 was the most active of this series with an IC50 of 5.6 mu M. A number of these derivatives further exhibited strong inhibition against HCV lb and 2a genotypes in cell based antiviral assays. Molecular docking analysis predicted that the thiazolidinone derivatives bind to the NS5B thumb pocketII (TP-II). Our results suggest that further optimization of the thiazolidinone scaffold may be possible to yield new derivatives with improved enzyme- and cell-based activity. (C) 2013 Elsevier Masson SAS. All rights reserved.Publication Open Access 2-MACHINE ORDERED FLOWSHOP SCHEDULING UNDER RANDOM BREAKDOWNS(PERGAMON-ELSEVIER SCIENCE LTD, 1994-07) ALLAHVERDI, A; MITTENTHAL, JThe problem of scheduling on a two-machine ordered flowshop, where machines suffer random breakdowns, is addressed with respect to the individual objectives of makespan and mean flowtime. An optimal sequence with makespan objective is obtained when only one of the two machines suffers random breakdowns. An optimal sequence with respect to mean flowtime is obtained when both machines are subject to random breakdowns.Publication Metadata only 2-mercaptoethane sulfonate (MESNA) protects against biliary obstruction-induced oxidative damage in rats(ELSEVIER IRELAND LTD, 2006) ERCAN, FERİHA; Sener, G; Kabasakal, L; Sehirli, O; Ercan, F; Gedik, NThe aim of this study was to assess the antioxidant and antifibrotic effects of chronic administration of 2-mercaptoethane sulfonate (MESNA) on oxidative liver damage and fibrosis induced by biliary obstruction in rats. Liver fibrosis was induced in male Wistar albino rats by bile duct ligation and scission (BDL). MESNA (150 mg/kg, i.p.) or saline was administered for 28 days. At the end of the experiment, rats were killed by decapitation. Serum aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels were determined to assess liver function. Tumor necrosis factor-alpha (TNF-alpha) and lactate dehidrogenase (LDH) were also assayed in serum samples. Liver tissues were taken for determination of the free radicals, hepatic malondialdehyde (MDA) levels, an end product of lipid peroxidation; glutathione (GSH) levels, a key antioxidant; myeloperoxidase (MPO) activity, as an indirect index of neutrophil infiltration. Hepatic collagen content, as a fibrosis marker was also determined. Serum AST, ALT, LDH and TNF-alpha levels were elevated in the BDL group as compared to control group, while this increase was significantly decreased by MESNA treatment. BDL caused a significant (p < 0.05-0.001) decrease in GSH levels while MDA levels and MPO activity were increased in the liver tissue. These changes were reversed by MESNA treatment. Collagen contents of the liver tissue was increased by BDL (P < 0.001), and reversed back to the control levels with MESNA. Since MESNA administration alleviated the BDL-induced oxidative injury of the liver and improved the hepatic functions, it seems likely that MESNA with its antioxidant and antifibrotic properties, may be of potential therapeutic value in protecting the liver fibrosis and oxidative injury due to biliary obstruction. (c) 2006 Published by Elsevier Ireland Ltd.