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      • KCI등재

        A comparative investigation of biochemical and histopathological effects of thiamine and thiamine pyrophosphate on ischemia– reperfusion induced oxidative damage in rat ovarian tissue

        Ismail Demiryilmaz,Ebru Sener,Nihal Cetin,Durdu Altuner,Fatih Akcay,Halis Suleyman 대한약학회 2013 Archives of Pharmacal Research Vol.36 No.9

        In this study, the biochemical and histopathologicaleffects of thiamine and thiamine pyrophosphate onischemia–reperfusion induced oxidative damage in ratovarian tissue were investigated. Animals were divided intofour groups of six rat each, ovarian ischemia–reperfusion(IR), 25 mg/kg thiamine ? ovarian ischemia–reperfusion(TIR), 25 mg/kg thiamine pyrophosphate ? ovarian ischemia–reperfusion (TPIR) and Sham group (SG). The resultsof the biochemical experiments have shown that the ratovarian tissue with thiamine treatment, the level of MDA,GSH and the 8-hydroxyguanine are almost the same as theIR group; while in the group with thiamine pyrophosphatetreatment, the level of MDA, GSH and the 8-hydroxyguanineare almost the same as the SG. Ovarian tissue of rats inthe IR group were congested and dilated vessels, edema,hemorrhage, necrotic and apoptotic cells. In this group, themigration and the adhesion of the polymorphonuclear leucocytesto the endothelium were observed. Both ovaries inTPIR group, there was no difference according to the SG. Histopathology of ovarian tissues in the TIR group wasalmost the same with the IR group. Our results indicate thatthiamine pyrophosphate significantly prevents the ischemia–reperfusion induced oxidative damage in ovarian tissue,whereas thiamine has no effect. In conclusion, we havefound that thiamine pyrophosphate prevents oxidativedamage due to ischemia–reperfusion injury, whereasthiamine does not have this effect. Furthermore, we haveconfirmed that the results of our biochemical analyses are inconcordance with the histopathological findings.

      • SCOPUSKCI등재

        Hypopituitarism and Legg-Calve-Perthes disease related to difficult delivery

        Bas, Veysel Nijat,Uytun, Salih,Vurdem, Umit Erkan,Torun, Yasemin Altuner The Korean Pediatric Society 2015 Clinical and Experimental Pediatrics (CEP) Vol.58 No.7

        Legg-Calve-Perthes (LCP) disease is characterized by idiopathic avascular osteonecrosis of the epiphysis of the femur head. The main factor that plays a role in the etiology of the disease is decreased blood flow to the epiphysis. Many predisposing factors have been suggested in the etiology of LCP disease, and most have varying degrees of effects. Here we present the case of a boy aged 4 years and 10 months with complaints of short stature and a diagnosis of multiple hypophyseal hormone deficiency, in whom LCP disease and difficult birth-related pituitary stalk interruption syndrome were identified by anamnesis. The present case revealed that LCP disease and hypophyseal hormone deficiency could be secondary to difficult birth and that LCP disease could be secondary to insulin-like growth factor 1 deficiency. Additionally, to the best of our knowledge there is no published case on the relation between LCP disease and insulin-like growth factor 1 deficiency. Therefore, we believe that this case is worthy of presentation.

      • KCI등재

        Hypopituitarism and Legg-Calve-Perthes disease related to difficult delivery

        Veysel Nijat Bas,Salih Uytun,Ümit Erkan Vurdem,Yasemin Altuner Torun 대한소아청소년과학회 2015 Clinical and Experimental Pediatrics (CEP) Vol.58 No.7

        Legg-Calve-Perthes (LCP) disease is characterized by idiopathic avascular osteonecrosis of the epiphysis of the femur head. The main factor that plays a role in the etiology of the disease is decreased blood flow to the epiphysis. Many predisposing factors have been suggested in the etiology of LCP disease, and most have varying degrees of effects. Here we present the case of a boy aged 4 years and 10 months with complaints of short stature and a diagnosis of multiple hypophyseal hormone deficiency, in whom LCP disease and difficult birth-related pituitary stalk interruption syndrome were identified by anamnesis. The present case revealed that LCP disease and hypophyseal hormone deficiency could be secondary to difficult birth and that LCP disease could be secondary to insulin-like growth factor 1 deficiency. Additionally, to the best of our knowledge there is no published case on the relation between LCP disease and insulin-like growth factor 1 deficiency. Therefore, we believe that this case is worthy of presentation.

      • KCI등재

        Diagnostic role of mean platelet volume and neutrophil to lymphocyte ratio in childhood brucellosis

        ( Sefika Elmas Bozdemir ),( Yasemin Ay Altlntop ),( Salih Uytun ),( Humeyra Aslaner ),( Yasemin Altuner Torun ) 대한내과학회 2017 The Korean Journal of Internal Medicine Vol.32 No.6

        Background/Aims: Brucellosis patients present various non-specific clinical symptoms, such as fever, fatigue, sweating, joint pain, arthritis, myalgia, and headache. Based on the nonspecifity of its clinical signs and symtoms, we decided to evaluate whether mean platelet volume (MPV), neutrophil to lymphocyte ratio (NLR), and platelet to lymphocyte ratio (PLR) will contribute to the diagnosis. Methods: In this retrospective study, we reviewed hospital-records of 60 children with a confirmed diagnosis of brucellosis in Kayseri between January 2013 and January 2016, and compared the hematological parameters; white blood cell (WBC) count, hemoglobin (Hb), neutrophil count, lymphocyte count, platelet count, MPV, NLR, and PLR with 55 healthy age and gender matched children. Also, the well known inf lammation markers; erytrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were compared between the patient and control group. Results: We found significant difference among the Hb, platelet count, MPV and NLR values between the patient and control group (p < 0.05). There was no difference between WBC, neutrophil count, lymphocyte count and PLR between the patient and control group (p > 0.05). When the patients were divided into groups as arthritis positive and arthritis negative and compared to the control group; we found that the NLR is more significant in between the arthritis positive and control group (p = 0.013). Also, we found significant difference among the ESR and CRP values between the patient and control group (p < 0.001). Conclusions: The results of this study indicates that MPV and NLR values can be used as markers of inflammation in childhood brucellosis. Also, NLR is more valuable in children with brucella arthritis.

      • KCI등재

        Effect of etoricoxib on experimental oxidative testicular ischemia–reperfusion damage in rats induced with torsion– detorsion

        Turgut Yapanoglu,Fatih Ozkaya,Ali Haydar Yilmaz,Renad Mammadov,Ferda Keskin Cimen,Erkan Hirik,Durdu Altuner 대한약리학회 2017 The Korean Journal of Physiology & Pharmacology Vol.21 No.5

        Etoricoxib features antioxidant and anti-inflammatory properties concomitantly, suggesting that it may be beneficial in testicular ischemia reperfusion (I/R) damage. Our aim is to investigate the effects of etoricoxib on testicular I/R damage induced with torsion-detorsion (TD). The etoricoxib + torsion-detorsion (ETD) groups of animals were given etoricoxib in 50 and 100 mg/kg of body weight (ETD- 50 and ETD-100), while the testes torsion-detorsion (TTD) and sham operation rat group (SOG) animals were given single oral doses of distilled water as a solvent. TTD, ETD-50 and ETD-100 groups were subjected to 720o degrees torsion for four hours, and detorsion for four hours. The SOG group was not subjected to this procedure. Biochemical, gene expression and histopathological analyses were carried out on the testicular tissues. The levels of malondialdehyde (MDA), myeloperoxidase (MPO), interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) were significantly higher, and the levels of total glutathione (tGSH) and glutathione reductase (GSHRd) were significantly lower in the TTD group, compared to the ETD-50, ETD-100 and SOG groups. Etoricoxib at a dose of 100 mg/kg better prevented I/R damage than the 50 mg/kg dose. Etoricoxib may be useful in clinical practice in the reduction of I/ R damage on testes caused by torsion-detorsion.

      • SCIESCOPUSKCI등재

        Effect of etoricoxib on experimental oxidative testicular ischemia-reperfusion damage in rats induced with torsion-detorsion

        Yapanoglu, Turgut,Ozkaya, Fatih,Yilmaz, Ali Haydar,Mammadov, Renad,Cimen, Ferda Keskin,Hirik, Erkan,Altuner, Durdu The Korean Society of Pharmacology 2017 The Korean Journal of Physiology & Pharmacology Vol.21 No.5

        Etoricoxib features antioxidant and anti-inflammatory properties concomitantly, suggesting that it may be beneficial in testicular ischemia reperfusion (I/R) damage. Our aim is to investigate the effects of etoricoxib on testicular I/R damage induced with torsion-detorsion (TD). The etoricoxib + torsion-detorsion (ETD) groups of animals were given etoricoxib in 50 and 100 mg/kg of body weight (ETD-50 and ETD-100), while the testes torsion-detorsion (TTD) and sham operation rat group (SOG) animals were given single oral doses of distilled water as a solvent. TTD, ETD-50 and ETD-100 groups were subjected to $720^{\circ}$ degrees torsion for four hours, and detorsion for four hours. The SOG group was not subjected to this procedure. Biochemical, gene expression and histopathological analyses were carried out on the testicular tissues. The levels of malondialdehyde (MDA), myeloperoxidase (MPO), interleukin-1 beta ($IL-1{\beta}$) and tumor necrosis factor alpha ($TNF-{\alpha}$) were significantly higher, and the levels of total glutathione (tGSH) and glutathione reductase (GSHRd) were significantly lower in the TTD group, compared to the ETD-50, ETD-100 and SOG groups. Etoricoxib at a dose of 100 mg/kg better prevented I/R damage than the 50 mg/kg dose. Etoricoxib may be useful in clinical practice in the reduction of I/R damage on testes caused by torsion-detorsion.

      • KCI등재

        Structural behavior of arch dams considering experimentally validated prototype model using similitude and scaling laws

        Ahmet Can Altunışık,Ebru Kalkan,Hasan B. Başağa 사단법인 한국계산역학회 2018 Computers and Concrete, An International Journal Vol.22 No.1

        As one of the most important engineering structures, arch dams are huge constructions built with human hands and have strategical importance. Because of the fact that long construction duration, water supply, financial reasons, major loss of life and material since failure etc., the design of arch dams is very important problem and should be done by expert engineers to determine the structural behavior more accurately. Finite element analyses and non-destructive experimental measurements can be used to investigate the structural response, but there are some difficulties such as spending a long time while modelling, analysis and in-situ testing. Therefore, it is more useful to conduct the research on the laboratory conditions and to transform the obtained results into real constructions. Within the scope of this study, it is aimed to determine the structural behavior of arch dams considering experimentally validated prototype laboratory model using similitude and scaling laws. Type-1 arch dam, which is one of five arch dam types suggested at the “Arch Dams” Symposium in England in 1968 is selected as reference prototype model. The dam is built considering dam-reservoir-foundation interaction and ambient vibration tests are performed to validate the finite element results such as dynamic characteristics, displacements, principal stresses and strains. These results are considered as reference parameters and used to determine the real arch dam response with different scales factors such as 335, 400, 416.67 and 450. These values are selected by considering previously examined dam projects. Arch heights are calculated as 201 m, 240 m, 250 m and 270 m, respectively. The structural response is investigated between the model and prototype by using similarity requirements, field equations, scaling laws etc. To validate these results, finite element models are enlarged in the same scales and analyses are repeated to obtain the dynamic characteristics, displacements, principal stresses and strains. At the end of the study, it is seen that there is a good agreement between all results obtained by similarity requirements with scaling laws and enlarged finite element models.

      • KCI등재

        Collapse of steel cantilever roof of tribune induced by snow loads

        Ahmet C. Altunışık,Şevket Ateş,Metin Hüsem,Ali F. Genç 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.23 No.3

        In this paper, it is aimed to present a detail investigation related to structural behavior of laterally unrestrained steel cantilever roof of tribune with slender cross section. The structure is located in Tutak town in A&$287;rı and collapsed on October 25, 2015 at eastern part of Turkey is considered as a case study. This mild sloped roof structure was built from a variable I beam, and supported on steel columns of 5.5 m height covering totally 240 m<sup>2</sup> closed area in plan. The roof of tribune collapsed completely without any indication during first snowfall after construction at midnight a winter day, fortunately before the opening hours. The meteorological records and observations of local persons are combined together to estimate the intensity of snow load in the region and it is compared with the code specified values. Also, the wide/thickness and height/thickness ratios for flange and web are evaluated according to the design codes. Three dimensional finite element model of the existing steel tribune roof is generated considering project drawings and site investigations using commercially available software ANSYS. The displacements, principal stresses and strains along to the cantilever length and column height are given as contour diagrams and graph format. In addition to site investigation, the numerical and analytical works conducted in this study indicate that the unequivocal reasons of the collapse are overloading action of snow load intensity, some mistakes made in the design of steel cantilever beams, insufficient strength and rigidity of the main structural elements, and construction workmanship errors.

      • KCI등재

        Stochastic response of suspension bridges for various spatial variability models

        Ahmet C. Altunışık,Süleyman Adanur,Kurtuluş Soyluk,A. Aydın Dumanoğlu 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.22 No.5

        The purpose of this paper is to compare the structural responses obtained from the stochastic analysis of a suspension bridge subjected to uniform and partially correlated seismic ground motions, using different spatial correlation functions commonly used in the earthquake engineering. The spatial correlation function employed in this study consists of a term that characterizes the loss of coherency. To account for the spatial variability of ground motions, the widely used four loss of coherency models in the literature has been taken into account in this study. Because each of these models has its own characteristics, it is intended to determine the sensitivity of a suspension bridge due to these losses of coherency models which represent the spatial variability of ground motions. Bosporus Suspension Bridge connects Europe to Asia in Istanbul is selected as a numerical example. The bridge has steel towers that are flexible, inclined hangers and a steel box-deck of 1074 m main span, with side spans of 231 and 255 m on the European and Asian sides, respectively. For the ground motion the filtered white noise model is considered and applied in the vertical direction, the intensity parameter of this model is obtained by using the S16E component of Pacoima Dam record of 1971 San Fernando earthquake. An analytically simple model called as filtered white noise ground motion model is chosen to represent the earthquake ground motion. When compared with the uniform ground motion case, the results obtained from the spatial variability models with partial correlation outline the necessity to include the spatial variability of ground motions in the stochastic dynamic analysis of suspension bridges. It is observed that while the largest response values are obtained for the model proposed by Harichandran and Vanmarcke, the model proposed by Uscinski produces the smallest responses among the considered partially correlated ground motion models. The response values obtained from the uniform ground motion case are usually smaller than those of the responses obtained from the partially correlated ground motion cases. While the response values at the flexible parts of the bridge are totally dominated by the dynamic component, the pseudo-static component also has significant contributions for the response values at the rigid parts of the bridge. The results also show the consistency of the spatial variability models, which have different characteristics, considered in this study.

      • KCI등재

        Vibrations of a Box-Sectional Cantilever Timoshenko Beam with Multiple Cracks

        Ahmet Can Altunışık,Fatih Yesevi Okur,Volkan Kahya 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.2

        This paper considers a Timoshenko cantilever beam with box cross-section including multiple cracks. Under six damage scenarios, the problem is solved analytically by the transfer matrix method, and numerically by the fi nite element method. Results are validated by the experimental measurements with the aid of ambient vibration tests, that use Enhanced Frequency Domain Decomposition and Stochastic Subspace Identifi cation methods. Measured and calculated natural frequencies and mode shapes for undamaged and damaged beams are compared with each other. Modal assurance criterion and coordinated modal assurance criterion values are obtained from two set of measurements to establish the correlation between the measured and calculated mode shapes for the damage location identifi cation.

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