Scopus İndekslenen Yayınlar

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12597/3197

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(1 → 3)-β-d-glucan enhances the toxicity induced by Bortezomib in rat testis
(2020-03-01) Akaras N.; Abuc O.O.; Koc K.; Bal T.; Geyikoglu F.; Atilay H.; Erol H.S.; Yigit S.; Gul M.
We aimed to determine the possible effects of the antioxidant agent (1 → 3)-β-D-glucan on bortezomib-induced rat testis damage. We used five groups of rats; control, (1 → 3)-β-D-glucan (75 mg/kg), bortezomib group, bortezomib + (1 → 3)-β-D-glucan groups (injection of (1 → 3)-β-D-glucan after bortezomib and sacrificed at 48th or 72nd h). The effects of these substances were assessed by measuring the levels of the antioxidant enzymes and LPO, and by performing immunohistochemical analysis with NF-κB. The histology of testis was evaluated using aniline blue staining. (1 → 3)-β-D-glucan leads to significant reductions in the levels of antioxidant enzymes and increased levels of LPO in testes. Moreover, it increased the NF-κB immunopositivity significantly in testis, especially in Bortezomib + (1 → 3)-β-D-glucan group at 48th h. The histological changes were observed in the bortezomib and/or (1 → 3)-β-D-glucan groups. Our results demonstrated that testis damage caused by the treatment with bortezomib was not eliminated by (1 → 3)-β-D-glucan and shockingly it increased the damage. Practical applications: The testis damage caused by the treatment with bortezomib was not eliminated by (1 → 3)-β-D-glucan and as a result, β-1,3-(D)-glucan enhanced the toxicity by leading a decrease in the levels of GSH, SOD, and CAT, thus caused an elevation in the immunoreactivity of NF-κB and altered the histopathological changes by enhancing the toxic effects of bortezomib. The findings of the previous studies about the antioxidative activity of (1 → 3)-β-D-glucan are controversial. So, it is necessary to consider the cytotoxicity of (1 → 3)-β-D-glucan in testis tissue. Thus, more studies on testis tissue are necessary to confirm that (1 → 3)-β-D-glucan is safe as an antioxidant.
1,2,3-Triazole substituted phthalocyanine metal complexes as potential inhibitors for anticholinesterase and antidiabetic enzymes with molecular docking studies
(2022-01-01) Koçyiğit Ü.M.; Taslimi P.; Tüzün B.; Yakan H.; Muğlu H.; Güzel E.
In recent years, acetylcholinesterase (AChE) and α-glycosidase (α-gly) inhibition have emerged as a promising and important approach for pharmacological intervention in many diseases such as glaucoma, epilepsy, obesity, cancer, and Alzheimer's. In this manner, the preparation and enzyme inhibition activities of peripherally 1,2,3-triazole group substituted metallophthalocyanine derivatives with strong absorption in the visible region were presented. These novel metallophthalocyanine derivatives (2-6) effectively inhibited AChE, with Ki values in the range of 40.11 ± 5.61 to 78.27 ± 15.42 µM. For α-glycosidase, the most effective Ki values of compounds 1 and 2 were with Ki values of 16.11 ± 3.13 and 18.31 ± 2.42 µM, respectively. Also, theoretical calculations were investigated to compare the chemical and biological activities of the ligand (1) and its metal complexes (2–6). Biological activities of 1 and its complexes against acetylcholinesterase for ID 4M0E (AChE) and α-glycosidase for ID 1R47 (α-gly) are calculated. Theoretical calculations were compatible with the experimental results and these 1,2,3-triazole substituted phthalocyanine metal complexes were found to be efficient inhibitors for anticholinesterase and antidiabetic enzymes. Communicated by Ramaswamy H. Sarma.
1-[4-(4-Chlorophenyl)piperazin-1-yl]-3-(6-oxo-3,4-diphenyl-1, 6-dihydropyridazin-1-yl)propan-1-one
(2012-09-01) Aydn A.; Akkurt M.; Doǧruer D.S.; Büyükgüngör O.
In the title compound, C29H27ClN4O 2, the six-membered ring of the pyridazine group is nearly planar [maximum deviation = -0.062 (2) Å] and its mean plane makes dihedral angles of 43.05 (9), 44.71 (10) and 72.57 (9)°, respectively, with the two phenyl and benzene rings. The piperazine ring has a chair conformation and its mean plane is almost perpendicular to the attached benzene ring, with a dihedral angle of 83.20 (16)°. In the crystal, molecules are linked via two pairs of C - H⋯O interactions, which result in the formation of chains propagating along [101̄]. Neighbouring chains are linked via C - H⋯π interactions.
1958 Iraq military coup with regard to Baghdad pact
(2018-03-01) Bostanci M.; Karaca E.
2-(6-Benzoyl-2-oxo-1,3-benzothiazol-3-yl)acetic acid
(2010-01-22) Aydn A.; Akkurt M.; Önkol T.; Büyükgüngör O.; Şahin M.F.
In the title compound, C16H11NO4S, the nine-membered fused ring is nearly planar, with maximum deviations from the mean plane of-0.022 (1) Å for the N atom and 0.011 (1) Å for the S atom, and makes a dihedral angle of 53.56 (7)° with the phenyl ring. The crystal structure is stabilized by O-H⋯O and C-H⋯O hydrogen-bonding inter-actions.
2-(6-Oxo-3,4-diphenyl-1,6-dihydro-pyridazin-1-yl)acetic acid
(2007-11-09) Aydin A.; Doǧruer D.; Akkurt M.; Büyükgüngör O.
In the title compound, C18H14N2O3, the pyridazine ring makes dihedral angles of 72.73 (11) and 49.97 (10)° with the two phenyl rings. The dihedral angle between the two phenyl rings is 52.42 (12)°. The crystal structure is stabilized by inter-molecular O - H⋯O and C - H⋯O hydrogen-bonding inter-actions. © International Union of Crystallography 2007.
2-[2-(4-Benzyl-piperazin-1-ylcarbon-yl)eth-yl]-5,6-diphenyl-pyridazin-3(2H) -one
(2008-12-12) Aydn A.; Doruer D.S.; Akkurt M.; Büyükgüngör O.
The title compound, C30H30N4O2, has a non-planar conformation, the dihedral angles formed by the pyridazinone ring plane and the three phenyl rings being 54.61 (7), 51.10 (7) and 59.53 (8)°. The piperazine ring adopts a chair conformation. Inter- and intra-molecular C - H⋯O contacts are found in the crystal structure and these consolidate the three-dimensional packing.
2-{2-[4-(4-Fluoro-phenyl)piperazin-1-yl]-2-oxoethyl}-6-(morpholin-4-yl) -4-phenyl-pyridazin-3(2H)-one
(2011-03-01) Aydin A.; Şüküroǧlu M.; Akkurt M.; Büyükgüngör O.
In the title compound, C26H28FN5O 3, the morpholine ring adopts a chair conformation. The piperazine ring is puckered [QT = 0.5437 (15) Å, θ = 8.89 (15) and φ = 357.2 (11)°]. The 1,6-dihydropyridazine ring makes dihedral angles of 28.03 (7) and 77.46 (7)° with the phenyl and benzene rings, respectively. In the crystal, molecules are linked along the c axis by C - H⋯O interactions and are flattened parallel to the ac plane. C - H⋯π interactions also contribute to the stability of the structure.
21.2 mV/K High-Performance Ni(50 nm)-Au(100 nm)/Ga2O3/p-Si Vertical MOS Type Diode and the Temperature Sensing Characteristics with a Novel Drive Mode
(2022-12-15) Cicek O.; Arslan E.; Altindal S.; Badali Y.; Ozbay E.
Sensitivity (S) and drive mode are crucial issues for the vertical metal-oxide-semiconductor (MOS) type diode applied in temperature sensing. In this study, experimentally, we indicated that the {S} values of the Ni50nm - Au100nm /Ga2O3/ p -Si vertical MOS type diode, using the measured capacitance-voltage (Cm - V) outputs, are obtained with a novel drive mode. We applied the constant capacitance mode to drive the silicon thermo-diodes as well as constant current mode, and constant voltage mode, which are known as two different methods in the literature. Meanwhile, the S value is 21.2 mV/K at 1 nF. This value is the highest value proven in the literature excepting the cryogenic temperature region, and near room temperature. This study provided an original structure for the silicon thermo-diodes and a novel way to drive them.
3-(4-Chloro-benzo-yl)-4-(4-chloro-phen-yl)-1-phenethyl-piperidin-4-ol
(2011-06-01) Aydin A.; Akkurt M.; Mete E.; Sahin E.; Gul H.
In the title compound, C26H25Cl2NO 2, the piperidine ring adopts a chair conformation with a cis configuration of the carbonyl and hy-droxy substituents. The dihedral angle between the aromatic rings of the chloro-benzene groups is 24.3 (2)°. The phenyl ring forms dihedral angles of 59.4 (3) and 44.1 (3)° with the benzene rings. In the crystal, mol-ecules are linked by inter-molecular O - H⋯N and C - H⋯O hydrogen bonds and C - H⋯π inter-actions into layers parallel to the bc plane.
3-({4-[(2-Methylbenzylidene)amino]-5-sulfanylidene-1H-1,2,4-triazol-3-yl} methyl)-1,3-benzoxazol-2(3H)-one
(2013-02-01) Aydn A.; Hekimoǧlu N.; Akkurt M.; Önkol T.; Çiçekli S.U.; Büyükgüngör O.
In the title compound, C18H15N5O2S, a weak intramolecular C - H⋯S hydrogen bond results in a small dihedral angle of 3.71 (9)° between the methylphenyl and triazole rings, which, in turn, form dihedral angles of 80.09 (8) and 77.32 (8)°, respectively, with the benzoxazolone mean plane. In the crystal, N - H⋯O hydrogen bonds link molecules into chains along [001], and weak C - H⋯N hydrogen bonds and π-π interactions between the five- and six-membered rings [centroid-centroid distances = 3.5074 (11) and 3.616 (1) Å] consolidate the crystal packing.
3-[6-(2-Chlorobenzoyl)-2-oxo-2,3-dihydro-1,3-benzothiazol-3-yl] propanenitrile
(2006-12-01) Aydin A.; Akkurt M.; Önkol T.; Büyükgüngör O.
The title compound, C17H11ClN2O 2S, crystallizes with two crystallographically independent molecules in the asymmetric unit. In the molecular structure, there are intramolecular weak C-H⋯O hydrogen bonds, which consolidate the molecular conformation. © 2006 International Union of Crystallography All rights reserved.
3-Anilinomethyl-5-chloro-1,3 - Benzoxazol-2(3H)-one
(2012-05-01) Aydin A.; Soyer Z.; Akkurt M.; Büyükgüngör O.
In the title compound, C14H11ClN2O 2, the 2,3-dihydro-1,3-benzoxazole ring system is essentially planar [maximum deviation = 0.009 (2) Å] and makes a dihedral angle of 79.15 (7)°with the phenyl ring. Inter-molecular N - H⋯O and weak C - H⋯Cl hydrogen bonds occur in the crystal structure. © Aydn et al. 2012.
3-Parameter Generalized Quaternions
(2022-09-01) Şentürk T.D.; Ünal Z.
In this article, we give a general form of the quaternions algebra depending on 3-parameters. We define 3-parameter generalized quaternions (3PGQs) and study various properties and applications. Firstly we present the definiton, the multiplication table and algebraic properties of 3PGQs. We give matrix representation and Hamilton operators for 3PGQs. We derive the polar represenation, De Moivre’s and Euler’s formulas with the matrix representations for 3PGQs. Additionally, we derive relations between the powers of the matrices associated with 3PGQs. Finally, Lie groups and Lie algebras are studied and their matrix representations are given. Also the Lie multiplication and the Killing bilinear form are given.
3D neutronic analysis in MHD calculations at ARIES-ST fusion reactors systems
(2014-01-01) Hançerliogulları A.; Cini M.
In this study, we developed new models for liquid wall (FW) state at ARIES-ST fusion reactor systems. ARIES-ST is a 1,000 MWe fusion reactor system based on a low aspect ratio ST plasma. In this article, we analyzed the characteristic properties of magnetohydrodynamics (MHD) and heat transfer conditions by using Monte-Carlo simulation methods (ARIES Team et al. in Fusion Eng Des 49-50:689-695, 2000; Tillack et al. in Fusion Eng Des 65:215-261, 2003). In fusion applications, liquid metals are traditionally considered to be the best working fluids. The working liquid must be a lithium-containing medium in order to provide adequate tritium that the plasma is self-sustained and that the fusion is a renewable energy source. As for Flibe free surface flows, the MHD effects caused by interaction with the mean flow is negligible, while a fairly uniform flow of thick can be maintained throughout the reactor based on 3-D MHD calculations. In this study, neutronic parameters, that is to say, energy multiplication factor radiation, heat flux and fissile fuel breeding were researched for fusion reactor with various thorium and uranium molten salts. Sufficient tritium amount is needed for the reactor to work itself. In the tritium breeding ratio (TBR) >1.05 ARIES-ST fusion model TBR is >1.1 so that tritium self-sufficiency is maintained for DT fusion systems (Starke et al. in Fusion Energ Des 84:1794-1798, 2009; Najmabadi et al. in Fusion Energ Des 80:3-23, 2006). © 2013 Springer Science+Business Media New York.
3D numerical analysis of a Li-ion battery cooling system with honeycomb configuration in electrical vehicles
(Elsevier B.V., 2024) Nazlı, C.; Gürdal, M.; Arslan, K.
This study focuses on the thermal challenges faced by lithium-ion batteries in electric vehicles and the importance of effective thermal management systems. It has been conducted a 3D numerical analysis to investigate the impact of different distances between batteries on heat transfer and flow characteristics in an air-cooled cooling module with an innovative honeycomb configuration. Boundary conditions and the study results were given with dimensionless parameters with longitudinal ratio (x/λ), distance ratio (λ), and height ratio (y/H). It was found that smaller distances between batteries let to higher temperatures at the beginning of the cooling channel due to the shorter channel width. However, as the distance between batteries increases, convective heat transfer performance improves, resulting in better temperature distributions and higher Nusselt numbers. The results shed light on the importance of optimizing the spatial arrangement of batteries in a cooling module to achieve efficient thermal management. This research contributes to bridging existing gaps in knowledge regarding battery thermal management in electric vehicles and provides insights for the design and development of more effective cooling strategies for lithium-ion batteries. In conclusion, according to the distance between batteries (S=1–3-5 mm) under a laminar flow regime, the best average Nussell numbers obtained for S=5 mm %17 and %7 heat enchantments compared to other S=1 mm and S=3mm cases, respectively. It can be observed that the convective heat transfer performance is optimal when all cases are located on the 9th battery. After the 9th battery column, the optimal heat transfer performance was observed for a thickness of 5 mm. The S=3 mm case exhibited a 7 % reduction in convective heat transfer performance compared to the S=5 mm case.
3D Printing of Gelatine/Alginate/β-Tricalcium Phosphate Composite Constructs for Bone Tissue Engineering
(2019-11-08) Kalkandelen C.; Ulag S.; Ozbek B.; Eroglu G.O.; Ozerkan D.; Kuruca S.E.; Oktar F.N.; Sengor M.; Gunduz O.
Bone tissue engineering studies have brought three-dimensional scaffolds into focus that can provide tissue regeneration with designed porosity and strengthened structure. Current research has concentrated on the fabrication of natural and synthetic polymer-based complex structures that closely mimic biological tissues due to their superior biocompatibility and biodegradabilities. Gelatine/Sodium Alginate hydrogels reinforced with different concentrations of β-Tricalcium Phosphate (TCP) (10, 13, and 15 wt.%) were studied to form 3D bone tissue. Physical, mechanical, chemical, morphological properties and biodegradability of the constructs were investigated. Furthermore, in vitro biological assay with human osteosarcoma cell line (SAOS-2) was performed to determine the biocompatibility of the constructs. It is found that cell viability rates for all constructs were increased and maximum cell viability rate was attained for 20%Gelatine/2%Alginate/10%TCP (wt.). The present work demonstrates that 3D printed Gelatine/Alginate/TCP constructs with porous structures are potential candidates for bone tissue engineering applications.
4-[(2E)-2-(4-Chlorobenzylidene)hydrazinylidene]-1-methyl-1, 4-dihydro-pyridine monohydrate
(2010-06-11) Aydn A.; Akkurt M.; Alptüzün V.; Büyükgüngör O.; Holzgrabe U.; Radacki K.
In the title compound, C13H12ClN3· H2O, the organic mol-ecule is almost planar, with a dihedral angle of 3.22 (10)° between the benzene and pyridine rings. The crystal structure is stabilized by O - H⋯N and C - H⋯O hydrogen bonding and π-π stacking inter-actions [centroid-centroid distances = 3.630 (1) and 3.701 (1) Å].
5-HT7 receptors as a new target for prostate cancer physiopathology and treatment: an experimental study on PC-3 cells and FFPE tissues
(2021-06-01) Cinar I.; Sirin B.; Halici Z.; Palabiyik-Yucelik S.S.; Akpinar E.; Cadirci E.
Prostate cancer (PCa) is one of the most common types of cancer seen among men worldwide. Previous studies have demonstrated that serotonin regulates cell proliferation, migration, and invasion in vitro; the presence of 5-HT receptors in cancer cells; and the role of serotonin in tumor development. The most recently discovered of these receptors is 5-HT7 but also least characterized receptors of serotonin. The aim of this study is to investigate the existence and possible role of 5-HT7 receptors in healthy and cancerous prostate tissues and also investigate effects of receptor agonists and antagonists on PC-3 cells to evaluate potential therapeutic effects. PC-3 cells were cultured and effects of 5-HT7 receptor agonist (LP-44) and antagonist (SB-269970) were evaluated on these cells. After proliferation analyses, relative expression of apoptotic markers and 5-HT7 receptor mRNA expression levels were determined through real-time PCR. Annexin V-FITC/PI double staining and Hoechst 33258 staining assay methods were applied to determine apoptosis. Additional PCR studies were performed on healthy and cancerous prostate tissue to see existence of receptors in human samples. The viability of PC-3 cells was decreased by SB-269970 after 48 and 72 h of incubation. However, LP-44 increased PC-3 cell proliferation at all time points. In 10-6 M SB-269970 treated PC-3 cells, there was significant increase in the expression of CAS-3 (4-fold), CAS-9 (2.5-fold), BAX (1.9-fold), and Tp-53 (4.8-fold) gene mRNA levels when compared to non-treated control group. Conversely, there was a significant decrease in NF-κB (2.9-fold) and 5-HT7 receptor (3.6-fold) mRNA expression in cells treated with SB-269970 when compared to control. SB-269970 that antagonized 5-HT7 receptors also induced apoptosis in Annexin V-FITC/PI double staining assay and Hoechst 33258 staining assays when compared with other groups. In human samples, 5-HT7 receptor mRNA expression was approximately 200-fold higher than that of heathy ones. In this study, for the first time, the 5-HT7 receptor antagonist SB-269970 has been shown to inhibit proliferation in PC-3 cells and to be associated with an apoptosis-inducing effect. These results suggest blocking 5-HT7 receptors can be a novel therapeutic target for the treatment of prostate cancer.
A 2-year aeropalynological survey of allergenic pollen in the atmosphere of Kastamonu, Turkey
(2012-09-01) Çeter T.; Pinar N.M.; Güney K.; Yildiz A.; Aşci B.; Smith M.
Knowledge of airborne pollen concentrations and the weather conditions influencing them is important for air quality forecasters, allergists and allergy sufferers. For this reason, a 7-day recording volumetric spore trap of the Hirst design was used for pollen monitoring between January 2006 and December 2007 in Kastamonu, Turkey. A total of 293,427 pollen grains belonging to 51 taxa were recorded during the study period. In the 2 years of study, the period March-August was identified as the main pollination season for Kastamonu. The highest monthly pollen counts were observed in May in both years. Six taxa made up 86.5% of the total amount of pollen recorded in the atmosphere of Kastamonu. These were as follows: Pinaceae (42.9%), Cupressaceae (20.6%), Poaceae (9.7%), Quercus (5.5%) Betula (5.3%) and Carpinus (2.6%). Four of these are considered to be highly allergenic (Betula, Carpinus, Cupressaceae and Poaceae). There were also a greater percentage of highly allergenic taxa found within the city, including Betula pendula that is not part of the local flora. This shows that through urban planting, the public and municipalities can unconsciously create a high risk for allergy sufferers. Daily average pollen counts from the six most frequently recorded pollen types were entered into Spearman's correlation analysis with meteorological data. Mean daily temperature, relative humidity, daily rainfall and wind speed were found to significantly (p < 0.05) affect atmospheric pollen concentrations, but the relationships between pollen concentrations and meteorological variables can vary and so there is a need for more local studies of this nature. © 2011 Springer Science+Business Media B.V.

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