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Clinical and Pathologic Features of Patients with Rare Ovarian Tumors: Multi-Center Review of 167 Patients by the Anatolian Society of Medical Oncology

  • Bilici, Ahmet;Inanc, Mevlude;Ulas, Arife;Akman, Tulay;Seker, Mesut;Babacan, Nalan Akgul;Inal, Ali;Bal, Oznur;Koral, Lokman;Sevinc, Alper;Tufan, Gulnihal;Elkiran, Emin Tamer;Ustaalioglu, Bala Basak Oven;Yavuzsen, Tugba;Alkis, Necati;Ozkan, Metin;Gumus, Mahmut
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권11호
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    • pp.6493-6499
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    • 2013
  • Background: Non-epithelial malignant ovarian tumors and clear cell carcinomas, Brenner tumors, transitional cell tumors, and carcinoid tumors of the ovary are rare ovarian tumors (ROTs). In this study, our aim was to determine the clinicopathological features of ROT patients and prognostic factors associated with survival. Materials and Methods: A total of 167 patients with ROT who underwent initial surgery were retrospectively analyzed. Prognostic factors that may influence the survival of patients were evaluated by univariate and multivariate analyses. Results: Of 167 patients, 75 (44.9%) were diagnosed with germ-cell tumors (GCT) and 68 (40.7%) with sex cord-stromal tumors (SCST); the remaining 24 had other rare ovarian histologies. Significant differences were found between ROT groups with respect to age at diagnosis, tumor localization, initial surgery type, tumor size, tumor grade, and FIGO stage. Three-year progression-free survival (PFS) rates and median PFS intervals for patients with other ROT were worse than those of patients with GCT and SCST (41.8% vs 79.6% vs 77.1% and 30.2 vs 72 vs 150 months, respectively; p=0.01). Moreover, the 3-year overall survival (OS) rates and median OS times for patients with both GCT and SCST were better as compared to patients with other ROT, but these differences were not statistically significant (87.7% vs 88.8% vs 73.9% and 170 vs 122 vs 91 months, respectively; p=0.20). In the univariate analysis, tumor localization (p<0.001), FIGO stage (p<0.001), and tumor grade (p=0.04) were significant prognostic factors for PFS. For OS, the univariate analysis indicated that tumor localization (p=0.01), FIGO stage (p=0.001), and recurrence (p<0.001) were important prognostic indicators. Multivariate analysis showed that FIGO stage for PFS (p=0.001, HR: 0.11) and the presence of recurrence (p=0.02, HR: 0.54) for OS were independent prognostic factors. Conclusions: ROTs should be evaluated separately from epithelial ovarian cancers because of their different biological features and natural history. Due to the rarity of these tumors, determination of relevant prognostic factors as a group may help as a guide for more appropriate adjuvant or recurrent therapies for ROTs.

Stochastic response of suspension bridges for various spatial variability models

  • Adanur, Suleyman;Altunisik, Ahmet C.;Soyluk, Kurtulus;Dumanoglu, A. Aydin
    • Steel and Composite Structures
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    • 제22권5호
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    • pp.1001-1018
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    • 2016
  • 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.

Should Cut-Off Values of the Risk of Malignancy Index be Changed for Evaluation of Adnexal Masses in Asian and Pacific Populations?

  • Yavuzcan, Ali;Caglar, Mete;Ozgu, Emre;Ustun, Yusuf;Dilbaz, Serdar;Ozdemir, Ismail;Yildiz, Elif;Gungor, Tayfun;Kumru, Selahattin
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권9호
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    • pp.5455-5459
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    • 2013
  • Background: The risk of malignancy index (RMI) for the evaluation of adnexal masses is a sensitive tool in certain populations. The best cut off value for RMI 1, 2 and 3 is 200. The cut off value of RMI-4 to differentiate benign from malignant lesions is 450. Our aim was to evaluate the efficiency of four different malignancy indexes (RMI1-4) in a homogeneous population. Materials and Methods: We evaluated a total of 153 non-pregnant women with adnexal masses who did not have a history of malignancy and who were above 18 years of age. Results: A cut-off value of 250 for RMI-1 provided 95.9% inter-observer agreement, yielding 95.9% specificity, 93.5% negative predictive value, 75.0% sensitivity and 82.8% positive predictive value. A cut-off value of 250 for RMI-1 showed high performance in preoperative diagnosis of invasive malignant lesions than cut-off value of 200 in our population. A cut-off value of 350 for RMI-2 provided 94.5% inter-observed agreement, yielding 94.2% specificity, 93.4% negative predictive value, 75.0% sensitivity and 77.4% positive predictive value. RMI-2 showed the higher performance when the cut-off value was set at 350 in our population. A cut-off value of 250 provided 95.2% inter-observer agreement, yielding 95.0% specificity, 93.2% negative predictive value, 75.0% sensitivity, and 88.0% positive predictive value. RMI-3 showed the highest performance to diagnose malignant adnexal masses when the cut-off value was set at 250. In our study, RMI-4 showed similar statistical performance when the cut-off value was set at 400 [(Kappa: 0.684/p=0.000), yielding 93.8% inter-observer agreement, 93.4% specificity, 93.4% negative predictive value, 75.0% sensitivity, and 75.0% negative predictive value]. Conclusions: We showed successful utilization of RMIs in preoperative differentiation of benign from malignant masses. Many studies conducted in Asian and Pacific countries have reported different cut-off values as was the case in our study. We think that it is difficult to determine universally accepted cut-off values for RMIs for common use around the globe.

Glial Cell Line-Derived Neurotrophic Factor, S-100 Protein and Synaptophysin Expression in Biliary Atresia Gallbladder Tissue

  • Gurunluoglu, Semra;Ceran, Canan;Gurunluoglu, Kubilay;Kocbiyik, Alper;Gul, Mehmet;Yildiz, Turan;Bag, Harika Gozukara;Gul, Semir;Tasci, Aytac;Bayrakci, Ercan;Akpinar, Necmettin;Cin, Ecem Serbest;Ates, Hasan;Demircan, Mehmet
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제24권2호
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    • pp.173-186
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    • 2021
  • Purpose: Biliary atresia (BA) is a disease that manifests as jaundice after birth and leads to progressive destruction of the ductal system in the liver. The aim of this study was to investigate histopathological changes and immunohistochemically examine the expression of glial cell line-derived neurotrophic factor (GDNF), synaptophysin, and S-100 protein in the gallbladder of BA patients. Methods: The study included a BA group of 29 patients and a control group of 41 children with cholecystectomy. Gallbladder tissue removed during surgery was obtained and examined immunohistochemically and histopathologically. Tissue samples of both groups were immunohistochemically assessed in terms of GDNF, S-100 protein, and synaptophysin expression. Expression was classified as present or absent. Inflammatory activity assessment with hematoxylin and eosin staining and fibrosis assessment with Masson's trichrome staining were performed for tissue sample sections of both groups. Results: Ganglion cells were not present in gallbladder tissue samples of the BA group. Immunohistochemically, GDNF, synaptophysin, and S-100 expression was not detected in the BA group. Histopathological examination revealed more frequent fibrosis and slightly higher inflammatory activity in the BA than in the control group. Conclusion: We speculate that GDNF expression will no longer continue in this region, when the damage caused by inflammation of the extrahepatic bile ducts reaches a critical threshold. The study's findings may represent a missing link in the chain of events forming the etiology of BA and may be helpful in its diagnosis.

Control of the flow past a sphere in a turbulent boundary layer using O-ring

  • Okbaz, Abdulkerim;Ozgoren, Muammer;Canpolat, Cetin;Sahin, Besir;Akilli, Huseyin
    • Wind and Structures
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    • 제35권1호
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    • pp.1-20
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    • 2022
  • This research work presents an experimental study's outcomes to reveal the impact of an O-ring on the flow control over a sphere placed in a turbulent boundary layer. The investigation is performed quantitatively and qualitatively using particle image velocimetry (PIV) and dye visualization. The sphere model having a diamater of 42.5 mm is located in a turbulent boundary layer flow over a smooth plate for gap ratios of 0≤G/D≤1.5 at Reynolds number of 5 × 103. Flow characteristics, including patterns of instantaneous vorticity, streaklines, time-averaged streamlines, velocity vectors, velocity fluctuations, Reynolds stress correlations, and turbulence kinetic energy (), are compared and discussed for a naked sphere and spheres having O-rings. The boundary layer velocity gradient and proximity of the sphere to the flat plate profoundly influence the flow dynamics. At proximity ratios of G/D=0.1 and 0.25, a wall jet is formed between lower side of the sphere and flat plate, and velocity fluctuations increase in regions close to the wall. At G/D=0.25, the jet flow also induces local flow separations on the flat plate. At higher proximity ratios, the velocity gradient of the boundary layer causes asymmetries in the mean flow characteristics and turbulence values in the wake region. It is observed that the O-ring with various placement angles (𝜃) on the sphere has a considerable alteration in the flow structure and turbulence statistics on the wake. At lower placement angles, where the O-ring is closer to the forward stagnation point of the sphere, the flow control performance of the O-ring is limited; however, its impact on the flow separation becomes pronounced as it is moved away from the forward stagnation point. At G/D=1.50 for O-ring diameters of 4.7 (2 mm) and 7 (3 mm) percent of the sphere diameter, the -ring exhibits remarkable flow control at 𝜃=50° and 𝜃=55° before laminar flow separation occurrence on the sphere surface, respectively. This conclusion is yielded from narrowed wakes and reductions in turbulence statistics compared to the naked sphere model. The O-ring with a diameter of 3 mm and placement angle of 50° exhibits the most effective flow control. It decreases, in sequence, streamwise velocity fluctuations and length of wake recovery region by 45% and 40%, respectively, which can be evaluated as source of decrement in drag force.

Reparative, Neuroprotective and Anti-neurodegenerative Effects of Granulocyte Colony Stimulating Factor in Radiation-Induced Brain Injury Model

  • Gokhan Gurkan;Ozum Atasoy;Nilsu Cini;Ibrahim Halil Sever;Bahattin Ozkul;Gokhan Yaprak;Cansin Sirin;Yigit Uyanikgil;Ceren Kizmazoglu;Mumin Alper Erdogan;Oytun Erbas
    • Journal of Korean Neurosurgical Society
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    • 제66권5호
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    • pp.511-524
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    • 2023
  • Objective : This animal model aimed to compare the rat group that received brain irradiation and did not receive additional treatment (only saline) and the rat group that underwent brain irradiation and received Granulocyte colony stimulating factor (G-CSF) treatment. In addition, the effects of G-CSF on brain functions were examined by magnetic resonance (MR) imaging and histopathologically. Methods : This study used 24 female Wistar albino rats. Drug administration (saline or G-CSF) was started at the beginning of the study and continued for 15 days after whole-brain radiotherapy (WBRT). WBRT was given on day 7 of the start of the study. At the end of 15 days, the behavioral tests, including the three-chamber sociability test, open field test, and passive avoidance learning test, were done. After the behavioral test, the animals performed the MR spectroscopy procedure. At the end of the study, cervical dislocation was applied to all animals. Results : G-CSF treatment positively affected the results of the three-chamber sociability test, open-space test and passive avoidance learning test, cornu Ammonis (CA) 1, CA3, and Purkinje neuron counts, and the brain levels of brain-derived neurotrophic factor and postsynaptic density protein-95. However, G-CSF treatment reduced the glial fibrillary acidic protein immunostaining index and brain levels of malondialdehyde, tumor necrosis factor-alpha, nuclear factor kappa-B, and lactate. In addition, on MR spectroscopy, G-CSF had a reversible effect on brain lactate levels. Conclusion : In this first designed brain irradiation animal model, which evaluated G-CSF effects, we observed that G-CSF had reparative, neuroprotective and anti-neurodegenerative effects and had increased neurotrophic factor expression, neuronal counts, and morphology changes. In addition, G-CSF had a proven lactate-lowering effect in MR spectroscopy and brain materials.

A Silk Road Hero: King Chashtana

  • ELMALI, MURAT
    • Acta Via Serica
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    • 제3권2호
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    • pp.91-106
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    • 2018
  • During the Old Uighur period, many works were translated into Old Uighur under the influence of Buddhism. Among these works, literary works such as $Da{\acute{s}}akarmapath{\bar{a}}vad{\bar{a}}nam{\bar{a}}l{\bar{a}}$ hold an important place. These works were usually translated from Pali to Sanskrit, from Sanskrit to Sogdian, Tocharian and Chinese, and to Old Uighur from these languages. These works which were added to the Old Uighur repertoire by translation indicate that different peoples along the ancient Silk Road had deep linguistic interactions with one another. Aside from these works, other narratives that we have been so far unable to determine whether they were translations, adaptations or original works have also been discovered. The Tale of King Chashtana, which was found in the work titled $Da{\acute{s}}akarmapath{\bar{a}}vad{\bar{a}}nam{\bar{a}}l{\bar{a}}$, is one of the tales we have been unable to classify as a translation or an original work. This tale has never been discovered with this title or this content in the languages of any of the peoples that were exposed to Buddhism along the Silk Road. On the other hand, the person whom the protagonist of this tale was named after has a very important place in the history of India, one of the countries that the Silk Road goes through. Saka Mahakshatrapa Chashtana (or Cashtana), a contemporary of Nahapana, declared himself king in Gujarat. A short time later, Chashtana, having invaded Ujjain and Maharashtra, established a powerful Saka kingdom in the west of India. His descendants reigned in the region for a long time. Another important fact about Chashtana is that coinage minted in his name was used all along the Silk Road. Chashtana, who became a significant historical figure in north western India, inspired the name of the protagonist of a tale in Old Uighur. That it is probable that the tale of King Chashtana is an original Old Uighur tale and not found in any other languages of the Silk Road brings some questions to mind: Who is Chashtana, the hero of the story? Is he related to the Saka king Chashtana in any way? What sort of influence did Chashtana have on the Silk Road and its languages? If this tale which we have never encountered in any other language of the Silk Road is indeed an original tale, why did the Old Uighurs use the name of an important Saka ruler? Is Saka-Uighur contact in question, given tales of this kind? What can we say about the historical and cultural geography of the Silk Road, given the fact that coinage was minted in his name and used along the Silk Road? In this study, I will attempt to answer these questions and share the information we have gleaned about Chashtana the hero of the tale and the Saka king Chashtana. One of the main aim of this study is to reveal the relationship between the narrative hero Chashtana and the Saka king Chashtana according to this information. Another aim of this study is to understand the history of the Saka, the Uighur and the Silk Road and to reveal the relationship between these three important subjects of history. The importance of the Silk Road will be emphasized again with the understanding of these relations. In this way, new information about Chashtana, who is an important name in the history of the India and the Silk Road, will be put forward. The history of the Sakas will be viewed from a different perspective through the Old Uighur Buddhist story.

Multicenter Analysis of Gestational Trophoblastic Neoplasia in Turkey

  • Ozalp, Sabit Sinan;Telli, Elcin;Oge, Tufan;Tulunay, Gokhan;Boran, Nurettin;Turan, Taner;Yenen, Mufit;Kurdoglu, Zehra;Ozler, Ali;Yuce, Kunter;Ulker, Volkan;Arvas, Macit;Demirkiran, Fuat;Bese, Tugan;Tokgozoglu, Nedim;Onan, Anil;Sanci, Muzaffer;Gokcu, Mehmet;Tosun, Gokhan;Dikmen, Yilmaz;Ozsaran, Aydin;Terek, Mustafa Cosan;Akman, Levent;Yetimalar, Hakan;Kilic, Derya Sakarya;Gungor, Tayfun;Ozgu, Emre;Yildiz, Yunus;Kokcu, Arif;Kefeli, Mehmet;Kuruoglu, Serkan;Yuksel, Hasan;Guvenal, Tevfik;Hasdemir, Pinar Solmaz;Ozcelik, Bulent;Serin, Serdar;Dolanbay, Mehmet;Arioz, Dagistan Tolga;Tuncer, Nadire;Bozkaya, Hasan;Guven, Suleyman;Kulaksiz, Deniz;Varol, Fusun;Ali, Yanik;Ogurlu, Gonca;Simsek, Tayyup;Toptas, Tayfun;Dogan, Selen;Camuzoglu, Hakan;Api, Murat;Guzin, Kadir;Eray, Caliskan;Doger, Emek
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권8호
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    • pp.3625-3628
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    • 2014
  • Background: To evaluate the incidence, diagnosis and management of GTN among 28 centers in Turkey. Materials and Methods: A retrospective study was designed to include GTN patients attending 28 centers in the 10-year period between January 2003 and May 2013. Demographical characteristics of the patients, histopathological diagnosis, the International Federation of Gynecology and Obstetrics (FIGO) anatomical and prognostic scores, use of single-agent and multi-agent chemotherapy, surgical interventions and prognosis were evaluated. Results: From 2003-2013, there were 1,173,235 deliveries and 456 GTN cases at the 28 centers. The incidence was calculated to be 0.38 per 1,000 deliveries. According to the evaluated data of 364 patients, the median age at diagnosis was 31 years (range, 15-59 years). A histopathological diagnosis was present for 45.1% of the patients, and invasive mole, choriocarcinoma and PSTTs were diagnosed in 22.3% (n=81), 18.1% (n=66) and 4.7% (n=17) of the patients, respectively. Regarding final prognosis, 352 (96.7%) of the patients had remission, and 7 (1.9%) had persistence, whereas the disease was mortal for 5 (1.4%) of the patients. Conclusions: Because of the differences between countries, it is important to provide national registration systems and special clinics for the accurate diagnosis and treatment of GTN.