Browsing by Author "Yildiz A."
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Item G protein β3 subunit gene polymorphism in Turkish hypertensives(2008) Alioǧlu E.; Ercan E.; Tengiz I.; Yildiz A.; Saygi U.ö.T.S.; Çam F.S.; Berdeli A.Objective: G protein is one of the most important regulators of intracellular signaling pathways. C825T polymorphism of G protein β3 subunit is associated with increased intracellular signal transduction. The 825T allele has been found associated with a variety of cardiovascular risk factors, including hypertension. The aim of the present study was to investigate the association between the C825T polymorphism of the G protein β3 subunit and essential hypertension in Turkish population. Methods: This cross-sectional, case-controlled study included 209 patients with essential hypertension (Patient group) and 82 subjects with normal blood pressure (Control group). The G protein β3 subunit C825T gene polymorphism was determined by polymerase chain reaction. Hypertension was defined according to JNC VII criteria. Statistical analysis was performed using Chi square and unpaired t tests. Logistic regression analysis was used to study association between hypertension and genotypes. Results: We found that the frequencies of the G protein β3 subunit C825T polymorphism in hypertensive and control groups were 17.7%, 59.3%, 23.0% and 32.9%, 48.8%, 18.3%, (CC, CT, TT) respectively (χ2=7.963, p=0.019). In the multivariate logistic regression analysis CT genotype had 2.2 (OR=2.262, 95% CI 1.228-4.167, p=0.009), and TT genotype had 2.3 times (OR=2.335, 95% CI 1.089-5.008, p=0.029) greater risk of hypertension compared to CC genotype. Conclusion: It seems that the G protein β3 subunit C825T gene polymorphism is associated with systolic a diastolic blood pressure. Furthermore, the study indicates that the G protein β3 subunit may be a susceptible gene to essential hypertension.Item Exergetic performance assessment of solar photovoltaic cell (PV) assisted earth to air heat exchanger (EAHE) system for solar greenhouse cooling(2011) Yildiz A.; Ozgener O.; Ozgener L.An experimental system was developed and tested in order to investigate the exergetic performance of a solar photovoltaic system (PV) assisted earth-to-air heat exchanger (under ground air tunnel) that is used for greenhouse cooling at the Solar Energy Institute, Ege University, Izmir, Turkey. This system was under operational conditions successfully during the 2010 summer cooling season. This paper provides the experimental results obtained between 18th of August and 26th of August of in 2010. Exergy destruction in the system was calculated and presented in this paper using a reference temperature of 15 °C. Results are discussed and interpreted in the paper for various performance metrics, such as the effect of climatic conditions and operating conditions on the system performance. Results show that the system may be satisfactorily used for greenhouse cooling in the Mediterranean and Aegean regions of Turkey. © 2011 Elsevier B.V. All rights reserved.Item Energetic performance analysis of a solar photovoltaic cell (PV) assisted closed loop earth-to-air heat exchanger for solar greenhouse cooling: An experimental study for low energy architecture in Aegean Region(2012) Yildiz A.; Ozgener O.; Ozgener L.An experimental system was developed and tested in order to investigate the energetic performance of a solar photovoltaic system (PV) assisted earth-to-air heat exchanger (underground air tunnel) that is used for greenhouse cooling at the Solar Energy Institute, Ege University, Izmir, Turkey. Average value of temperature differences between inlet and outlet of earth-to-air heat exchanger (EAHE) was observed 8.29 °C at experimental measurements. The average heat discharge rate (cooling load) was realized as 5.02 kW by using 0.7 kW fan. System was operated about 11 h/day. As a result, total electricity energy consumption of the system was measured to be 8.10 kWh and 34.55% of this energy demand was provided from photovoltaic cells. Furthermore, 65.45% of the electricity energy demand was provided from grid connection. Results are discussed and interpreted in the paper for various performance metrics. © 2012 Elsevier Ltd.Item Predictive factors for the development of brain metastases in patients with malignant melanoma: A study by the Anatolian society of medical oncology(2014) Gumusay O.; Coskun U.; Akman T.; Ekinci A.S.; Kocar M.; Erceleb O.B.; Yazici O.; Kaplan M.A.; Berk V.; Cetin B.; Taskoylu B.Y.; Yildiz A.; Goksel G.; Alacacioglu A.; Demirci U.; Algin E.; Uysal M.; Oztop I.; Oksuzoglu B.; Dane F.; Gumus M.; Buyukberber S.Background: The development of brain metastases (BMs) was associated with poor prognosis in melanoma patients. Patients with BMs have a median survival of <6 months. Melanoma is the third most common tumor to metastasize to the brain with a reported incidence of 10-40 %. Our aim was to identify factors predicting development of BMs and survival. Patients and methods: We performed a retrospective analysis of 470 melanoma patients between 2000 and 2012. The logistic regression analyses were used to identify the clinicopathological features of primary melanoma that are predictive of BMs development and survival after a diagnosis of brain metastases. Results: There were 52 patients (11.1 %) who developed melanoma BMs during the study period. The analysis of post-BMs with Kaplan-Meier curves has resulted in a median survival rate of 4.1 months (range 2.9-5.1 months). On logistic regression analysis site of the primary tumor on the head and neck (p = 0.002), primary tumor thickness (Breslow >4 mm) (p = 0.008), ulceration (p = 0.007), and pathologically N2 and N3 diseases (p = 0.001) were found to be significantly associated with the development of BMs. In univariate analysis, tumor thickness and performance status had a significant influence on post-BMs survival. In multivariate analysis, these clinicopathologic factors were not remained as significant predictive factors. Conclusions: Our results revealed the importance of primary tumor characteristics associated with the development of BMs. Ulceration, primary tumor thickness, anatomic site, and pathologic ≥N2 disease were found to be significant predictors of BMs development. © 2013 Springer-Verlag Berlin Heidelberg.Item Impact of previous SWL on ureterorenoscopy outcomes and optimal timing for ureterorenoscopy after SWL failure in proximal ureteral stones(Springer, 2020) Irer B.; Sahin M.O.; Erbatu O.; Yildiz A.; Ongun S.; Cinar O.; Cihan A.; Sen V.; Ucer O.; Kizilay F.; Bozkurt O.Purpose: We aimed to evaluate the impact of previous unsuccessful shock wave lithotripsy (SWL) therapy on ureterorenoscopy (URS) outcomes in proximal ureteral stones and to define whether there is any optimal timing for safe URS after SWL. Methods: The patients who underwent URS for proximal ureteral stones between the years 2015 and 2018 in eight centers were included. Patients were divided into two groups according to previous SWL history; group 1 consisted of patients without SWL before URS for the stone [SWL (−)] and group 2 consisted of patients with a previous SWL for the stone [SWL (+)]. Demographics, operation outcomes and stone characteristics were compared between these two groups. Regarding the complication and success rates, optimal timing for URS after SWL for the stone was calculated with receiver operator characteristics curve analysis. Results: Totally 638 patients were included (group 1: 466 patients and group 2: 172 patients). The operation and hospitalization times, rate of ureteral stenting and complications were significantly higher in group 2. Stone free status was similar between the groups. Optimal timing for URS after SWL was calculated as 16.5 days (AUC = 0.657, p = 0.012) with a sensitivity of 68% and specificity of 72%, regarding the complication rates. Complication rates were significantly higher in patients who were operated before 16.5 days (27.7% vs 6.5%, p < 0.001). Conclusions: The optimal timing; 2–3 weeks delay of the URS procedure after unsuccessful SWL may decrease complication rates according to our results. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.Item Predictive Factors of Ureterorenoscopy Outcomes in Proximal Ureteral Stones: A Multicenter Study of Aegean Study Group of the Society of Urological Surgery(S. Karger AG, 2020) Sen V.; Irer B.; Erbatu O.; Yildiz A.; Ongun S.; Cinar O.; Cihan A.; Sahin M.O.; Ucer O.; Kizilay F.; Bozkurt O.Introduction: We aimed to evaluate the predictive factors in a holistic manner for ureterorenoscopy (URS) outcomes in proximal ureteral stones by a multicenter study. Materials and Methods: The data of patients who underwent URS for proximal ureteral stones between the years 2015 and 2018 in eight centers were recorded retrospectively. Patients were divided into two groups according to URS success: Group 1 consisted of patients with successful URS, and Group 2 consisted of patients with unsuccessful URS. The two groups were compared in terms of risk factors, stone, and clinical characteristics of patients. Results: A total of 638 patients were included in the study. Group 1 consisted of 527 (82.6%) patients, and Group 2 consisted of 111 (17.4%) patients. In multivariate logistic analysis, the key risk factors for URS success was found to be age (OR = 0.980, 95% [CI] = 0.963-0.996, p = 0.018), stone area (OR = 0.993, 95% [CI] = 0.989-0.997, p = 0.002), and operation time (OR = 0.981, 95% [CI] = 0.968-0.994, p = 0.005). Conclusions: To make the treatment decision of proximal ureteral stones, it is necessary to examine several parameters including available equipment, stone, and patient characteristics. Physicians should keep these risk factors in mind in the decision of treatment options. © 2019 S. Karger AG, Basel.Item Genetic Algorithm Approach based on Graph Theory for Location Optimization of Electric Vehicle Charging Stations(Institute of Electrical and Electronics Engineers Inc., 2021) Altundogan T.G.; Yildiz A.; Karakose E.Nowadays, with the increase in the economic and ecological disadvantages of internal combustion engine vehicles, the use of electric vehicles is becoming widespread. In addition, the widespread use of electric vehicles creates the need for optimal locating electric vehicle charging stations in urban areas. In this study, a Genetic Algorithm approach based on graph theory is developed to locate a certain number of charging stations in urban areas. In the proposed method, some points in the urban area are accepted as reference nodes. By considering the path relation and distance information between these reference nodes, the urban area is expressed with a weighted graph. The minimum cost paths between the reference points in the urban area expressed by graph were determined by the Dijkstra method. The obtained minimum cost paths are used in the fitness function of the GA. Then, a GA-based method is developed to distribute the charging stations homogeneously at the urban area. The proposed method is tested on a virtual urban area with 20 reference nodes. The obtained results showed that the proposed method is a suitable method for distance-based charging station location determination. © 2021 IEEE.Item Nationwide prospective audit for the evaluation of appendicitis risk prediction models in adults: Right iliac fossa treatment (RIFT) - Turkey(Oxford University Press, 2024) Yalcinkaya A.; Yalcinkaya A.; Balci B.; Keskin C.; Erkan I.; Yildiz A.; Kamer E.; Leventoglu S.; Caglikulekci M.; Zarbaliyev E.; Sevmis M.; Ulgen Y.; Altinel Y.; Meric S.; Akbas A.; Hacim N.A.; Vartanoglu Aktokmanyan T.; Aktimur Y.E.; Calikoglu F.; Gullu H.F.; Durma A.G.; Acar S.; Ciftci E.; Balik E.; Kulle C.B.; Ozata I.H.; Tufekci T.; Tatar C.; Sevinc M.M.; Sevik H.; Ertürk C.; Kiraz I.N.; Ozben V.; Aytac E.; Aliyeva Z.; Mutlu A.U.; Tanal M.; Celayir M.F.; Bozkurt E.; Yetkin S.G.; Ergin E.; Attaallah W.; Uprak T.K.; Omak A.; Simsek O.; Bozkurt M.A.; Kara Y.; Bozdag E.; Yirgin H.; Ozcan A.; Okkabaz N.; Ozdenkaya Y.; Haksal M.C.; Pekuz C.K.; Duru S.; Sivrikoz E.; Ozdemir Y.; Tan N.; Yarbug Karayali F.; Taghiyeva A.; Tirnova I.; Erenler Bayraktar I.; Bayraktar O.; Emsal E.Z.; Dalkilic M.I.; Yesiltas M.; Tok H.; Karakas D.O.; Pusane A.; Demirer A.I.; Sahin H.B.; Gok A.F.K.; Bozkurt H.A.; Yildirim M.; Uzunyolcu G.; Yanar H.T.; Ergun S.; Kutluk F.; Uludag S.S.; Zengin A.K.; Ozcelik M.F.; Sanli A.N.; Altuntas Y.E.; Memisoglu E.; Sari R.; Akdogan O.; Kucuk H.F.; Ozkan O.F.; Ulgur H.S.; Kirkan E.F.; Yuksekdag S.; Rencuzogullari A.; Aktas M.K.; Aba M.; Demirel A.O.; Eray I.C.; Aydogan B.; Cetinkunar S.; Yener K.; Sozutek A.; Irkorucu O.; Bayrak M.; Altintas Y.; Alabaz O.; Atasever A.; Erdogrul G.; Kupeli A.H.; Muhammedoglu B.; Kokdas S.; Kaya M.; Uysal E.; Yildirim A.C.; Zeren S.; Ekici M.F.; Algin M.C.; Kucuk G.O.; Eraslan H.; Aybar E.; Polat S.; Ceylan A.; Isik O.; Kural S.; Aktas A.; Bakar B.; Uzunoglu M.Y.; Gulcu B.; Ozturk E.; Devay A.O.; Taspinar E.; Balcin O.; Aksoy F.; Garip G.; Yalkin O.; Iflazoglu N.; Yigit D.; Kaya R.B.; Ugur M.; Kilic E.; Dedemoglu A.; Arslan R.E.; Temiz M.; Aydin C.; Demirli Atici S.; Kaya T.; Ozturk S.; Calik B.; Kilinc G.; Acar T.; Acar N.; Cengiz F.; Ureyen O.; Tan S.; Ilhan E.; Turk Y.; Durak A.T.; Yilmaz M.; Mercan M.; Atci R.; Sokmen S.; Bisgin T.; Egeli T.; Yildirim Y.; Safak T.; Celik K.; Yilmaz E.M.; Kirnap M.; Demirkiran A.E.; Sekerci U.U.; Karacan E.; Bilgic E.; Ozmen M.M.; Guldogan C.E.; Gundogdu E.; Moran M.; Erol T.; Dincer H.A.; Kirimtay B.; Yilmaz S.; Cennet O.; Yildiz A.; Sahin C.; Akyol C.; Koc M.A.; Ersoz S.; Turhan A.; Konca C.; Tezcaner T.; Erkent M.; Aydin O.; Avci T.; Altiner S.; Osmanov I.; Emral A.C.; Cetinkaya G.; Lapsekili E.; Sakca M.; Cimen S.; Ozen D.; Kozan E.B.; Dogan L.; Haberal E.; Kayhan O.; Aksel B.; Karabacak H.; Azili C.; Yazici F.; Apaydin M.; Kaya I.O.; Cetinkaya E.; Akin T.; Gunes G.; Turap H.; Aslan D.; Demirbag A.E.; Bolukbasi B.; Karaca B.E.; Ozturk E.; Ozeller E.; Kayacan G.S.; Borcek A.O.; Ece I.; Yormaz S.; Colak B.; Calisir A.; Sahin M.; Arslan K.; Hasirci I.; Ulutas M.E.; Metin S.H.; Gultekin F.A.; Ozkan Z.; Ilhan O.; Gundogdu T.; Liman R.K.; Kanat B.H.; Aydin A.; Sungurtekin U.; Ozgen U.; Aykota M.R.; Altintoprak F.; Gonullu E.; Cakmak G.; Dulger U.C.; Mantoglu B.; Demir H.; Akin E.; Eroz E.; Nazli O.; Dere O.; Dadasoglu M.A.; Kara E.; Tutcu S.; Solak I.; Gencer I.; Dalkiran A.; Sevinc B.; Karahan O.; Damburaci N.; Sari E.; Akay T.; Calta A.F.; Ozdemir A.; Ohri N.; Ermis I.; Bozbiyik O.; Ozdemir M.; Goktepe B.; Demir B.; Kilincarslan O.; Gunduz U.R.; Olcum M.; Dincer O.I.; Cakir R.C.; Dinc B.; Sahin E.; Uludag E.; Arslan Y.; Posteki G.; Oktay A.; Tatar O.C.; Guler S.A.; Utkan N.Z.; Tayar S.; Copelci Y.; Kartal M.; Kalayci T.; Yeni M.; Buyukkasap A.C.; Vural S.; Kesicioglu T.; Aydin I.; Gulmez M.; Saracoglu C.; Topcu O.; Kurt A.; Soylu S.; Kurt B.; Serin M.; Basceken S.I.; Gundes E.; Savda M.; Balkan A.Z.A.; Yildiz M.N.; Uzunkoy A.; Karaca E.; Berkan A.; Isik A.; Yildiz Y.A.; Ergul Z.; Yasar N.F.; Badak B.; Ozen A.; Velipasaoglu M.; Ure I.Background: Appendicitis is the most prevalent surgical emergency. The negative appendicectomy rate and diagnostic uncertainty are important concerns. This study aimed to assess the effectiveness of current appendicitis risk prediction models in patients with acute right iliac fossa pain. Methods: A nationwide prospective observational study was conducted, including all consecutive adult patients who presented with right iliac fossa pain. Diagnostic, clinical and negative appendicectomy rate data were recorded. The Alvarado score, Appendicitis Inflammatory Response (AIR), Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA) and Adult Appendicitis Score systems were calculated with collected data to classify patients into risk categories. Diagnostic value and categorization performance were evaluated, with use of risk category-based metrics including 'true positive rate' (percentage of appendicitis patients in the highest risk category), 'failure rate' (percentage of patients with appendicitis in the lowest risk category) and 'categorization resolution' (true positive rate/failure rate). Results: A total of 3358 patients from 84 centres were included. Female patients were less likely to undergo surgery than men (71.5% versus 82.5% respectively; relative risk 0.866, 95% c.i. 0.834 to 0.901, P < 0.001); with a three-fold higher negative appendicectomy rate (11.3% versus 4.1% respectively; relative risk 2.744, 95% c.i. 2.047 to 3.677, P < 0.001). Ultrasonography was utilized in 56.8% and computed tomography in 75.2% of all patients. The Adult Appendicitis Score had the best diagnostic performance for the whole population; however, only RIPASA was significant in men. All scoring systems were successful in females patients, but Adult Appendicitis Score had the highest area under the receiver operating characteristic curve value. The RIPASA and the Adult Appendicitis Score had the best categorization resolution values, complemented by their exceedingly low failure rates in both male and female patients. Alvarado and AIR had extremely high failure rates in men. Conclusion: The negative appendicectomy rate was low overall, but women had an almost three-fold higher negative appendicectomy rate despite lower likelihood to undergo surgery. The overuse of imaging tests, best exemplified by the 75.2% frequency of patients undergoing computed tomography, may lead to increased costs. Risk-scoring systems such as RIPASA and Adult Appendicitis Score appear to be superior to Alvarado and AIR. © 2024 The Author(s). Published by Oxford University Press on behalf of BJS Foundation Ltd.Item Comparison of the efficacy of sunitinib and pazopanib in patients with advanced non-clear renal cell carcinoma(Taylor and Francis Ltd., 2024) Yildirim H.C.; Bayram E.; Chalabiyev E.; Majidova N.; Avci T.; Güzel H.G.; Kapar C.; Uzun M.; Perkin P.; Akgül F.; Yildirim S.S.; Sali S.; Yildiz A.; Kazaz S.N.; Hendem E.; Arcagok M.; Tufan G.; Yildirim U.; Akgul O.F.; Arslan Ç.; Taban H.; Sahin E.; Caglayan M.; Esen R.; Öksüzoğlu B.; Guven D.C.; Kaplan M.A.; Araz M.; Basaran M.; Cubukcu E.; Gokmen E.; Cicin I.; Algin E.; Semiz H.S.; Tural D.; Ozturk B.; Erdogan A.P.; Sari M.; Kara O.; Erman M.Non-clear cell renal cell carcinoma (non-ccRCC) is a highly heterogeneous disease group, accounting for approximately 25% of all RCC cases. Due to its rarity and especially heterogeneity, phase III trial data is limited and treatment options generally follow those of clear cell RCC. In the literature, there exists a number of studies with sunitinib, cabozantinib, and everolimus, but data on the efficacy of pazopanib are limited. Our aim in this study was to compare the efficacy of pazopanib and sunitinib, in a multicenter retrospective cohort of non-ccRCC patients. Our study included patients diagnosed with non-ccRCC who received pazopanib or sunitinib treatment as first-line therapy from 22 tertiary hospitals. We compared the progression-free survival (PFS), overall survival (OS), and response rates of pazopanib and sunitinib treatments. Additionally, we investigated prognostic factors in non-ccRCC. PFS and response rates of sunitinib and pazopanib were found to be similar, while a numerical difference was observed in OS. Being 65 years and older, being in the intermediate or poor risk group according to the International Metastatic Renal Cell Carcinoma Database Consortium, having liver metastases, presence of a sarcomatoid component, and having de novo metastatic disease were found to be significantly associated with shorter PFS. Pazopanib treatment appears to have similar efficacy in the treatment of non-ccRCC compared to sunitinib. Though randomized controlled trials are lacking and will probably be never be available, we suggest that pazopanib could be a preferred agent like sunitinib and cabozantinib. © 2024 Edizioni Scientifiche per l’Informazione su Farmaci e Terapia (Italian Society of Chemotherapy).