Akademik Arşiv / Academic Archive

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1 : 1 binary complexes of citric acid with some metal ions: Stability and thermodynamic parameters
(WALTER DE GRUYTER GMBH, 2007) Bastug, A. Seza; Gokturk, Sinem; Sismanoglu, Tuba
The stability constants of the 1:1 binary complexes of citric acid with Cu2+, Ni2+ CO2+ Mn2+ and Ce3+ were determined potentiometrically at 15.0, 25.0, and 35.0 degrees 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, Delta G(o), Delta H-o, and Delta S-o were reported for the complexes formation reactions. The enthalpy and entropy changes of all binary complexes are positive.
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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, Mustafa
In 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.
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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, Halit
In 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.
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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, AS
A 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.
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1,4-Dithiaheterocycle-fused porphyrazines: Synthesis, characterization, voltammetric and spectroelectrochemical properties
(ELSEVIER SCI LTD, 2009) KOCA, ATIF; Tuncer, Serap; Koca, Atif; Guel, Ahmet; Avciata, Ulvi
Porphyrazines (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.
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1-[P-(BENZOYLAMINO)BENZOYL]-4-SUBSTITUTED THIOSEMICARBAZIDES - SYNTHESIS AND ANTIBACTERIAL AND ANTIFUNGAL ACTIVITIES
(GOVI-VERLAG GMBH, 1992) KALYONCUOGLU, N; ROLLAS, S; SURALTINER, D; YEGENOGLU, Y; ANG, O
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1-ACETYLHYDROQUINONE 4-GALACTOSIDE FROM FERULAGO-AUCHERI
(PERGAMON-ELSEVIER SCIENCE LTD, 1991) DOGANCA, S; ULUBELEN, A; TUZLACI, E
From 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.
Open Access
11 beta-hydroxysteroid dehydrogenase type 1 gene expression is increased in ascending aorta tissue of metabolic syndrome patients with coronary artery disease
(FUNPEC-EDITORA, 2012) Atalar, F.; Vural, B.; Ciftci, C.; Demirkan, A.; Akan, G.; Susleyici-Duman, B.; Gunay, D.; Akpinar, B.; Sagbas, E.; Ozbek, U.; Buyukdevrim, A. S.
11 beta-hydroxysteroid dehydrogenase type 1 (11 beta-HSD-1) activity and mRNA levels are increased in visceral and subcutaneous adipose tissues of metabolic syndrome subjects. We analyzed 11 beta-HSD-1 expression in human epicardial adipose (EA) and ascending aorta (AA) tissues of metabolic syndrome patients and examined their contribution to the development of coronary atherosclerosis. The 11 beta-HSD-1 expression was evaluated by qRT-PCR in EA and AA tissues of 20 metabolic syndrome patients with coronary artery disease (metabolic syndrome group) and 10 non-metabolic syndrome patients without coronary artery disease (controls). 11 beta-HSD-1 expression was increased in EA and AA tissues of the metabolic syndrome group (4.1-and 5.5-fold, respectively). A significant positive correlation was found between 11 beta-HSD-1 expression in EA tissue and waist hip ratio and 11 beta-HSD-1 expression in AA tissue and body mass index, while a negative correlation was found between 11 beta-HSD-1 expression in EA tissue and HDL. Expression of CD68, a macrophage marker, was significantly increased in both tissues of the metabolic syndrome group; it was 2-fold higher in AA tissue compared to EA tissue in the metabolic syndrome group. Our findings of increased expression of 11 beta-HSD-1 and CD68 in AA tissue of the metabolic syndrome group lead us to suggest that they contribute to coronary atherosclerosis in metabolic syndrome. This positive correlation between obesity markers and 11 beta-HSD-1 in AA and EA tissues strengthens the evidence that 11 beta-HSD-1 has a role in metabolic syndrome. To the best of our knowledge, this is the first report showing 11 beta-HSD-1 and CD68 expression in AA tissue of metabolic syndrome patients. We suggest that there is tissue-specific expression of 11 beta-HSD-1 in metabolic syndrome and associated cardiovascular disorders.
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11th European Congress on Clinical Microbiology and Infectious Diseases - Istanbul, Turkey, 2 April 2001 - Introduction
(W B SAUNDERS CO LTD, 2002) KORTEN, VOLKAN; Finch, R; Korten, V
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17 beta-estradiol (E2) modulates response of endothelial cells to caffeine.
(FEDERATION AMER SOC EXP BIOL, 1998) Bilsel, S; Moini, H
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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, K
In 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.
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, A
Objective: 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.
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17-beta-Estradiol increases cytosolic free calcium concentrations ([Ca2+](1)) of endothelial cells and modulates the responses to acetylcholine.
(FEDERATION AMER SOC EXP BIOL, 1996) Bilsel, AS; Moini, H; Bekdemir, T; Emerk, K
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17-HYDROXYLASE DEFICIENCY: RARE CAUSE OF DELAYED PUBERTY
(KARGER, 2017) Guven, Ayla; Guran, Tulay; Krone, Nils
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, Korkut
Interleukin-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.
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17OH-PREGNENOLONE SEEMS A MAJOR DRIVE OF ANDROGEN EXCESS IN PATIENTS WITH 11 beta-HYDROXYLASE DEFICIENCY
(KARGER, 2017) Yildiz, Melek; Turan, Serap; Akcay, Teoman; Atay, Zeynep; Onal, Hasan; Baris, Tugba; Haklar, Goncagul; Bereket, Abdullah; Guran, Tulay
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18F-FDG PET / CT findings of Rosai Dorfman Disease with diffuse extranodal involvement
(SPRINGER, 2020) Filizoglu, N.; Kesim, S.; Engur, C. O.; Oksuzoglu, K.; Ozguven, S.; Ones, T.; Turoglu, H. T.; Erdil, T. Y.
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18F-FDG PET/CT Findings and Baseline Clinical Parameters in Multiple Myeloma
(CIG MEDIA GROUP, LP, 2017) ATAGÜNDÜZ, IŞIK; Tuglular, Tulin Firatli; Tanrikulu, Funda Pepedil; Toptas, Tayfur; Karadeniz, Asli; Atagunduz, Isik
Open Access
18f-fluorodeoxyglucose (fdg) pet-ct imaging of salivary glands in primary sjogren's syndrome and its correlation with ultrasonographic scores and salivary flow rate compared to healthy controls
(2022-06-01) ÖNEŞ, TUNÇ; MUMCU, GONCA; Abacar K., Kissa T. N. , Oksuzoglu K., Ones T., Mumcu G., Bruyn G., Inanc N.
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(2, J)-IDEALS IN COMMUTATIVE RINGS
(PUBL HOUSE BULGARIAN ACAD SCI, 2020) Yildiz, Eda; Tekir, Unsal; Koc, Suat
Let 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.

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