Browsing by Author "Sahin, S."

Now showing 1 - 7 of 7

238u and 222rn Activity Concentrations and Total Radioactivity Levels in Lake Waters
(Springer, 2013) Zorer, O. Selcuk; Sahan, T.; Ceylan, H.; Dogru, M.; Sahin, S.
The concentrations and distributions of natural radioactivity, uranium and radon in lake waters from around Van, Turkey were investigated with an aim of evaluating the environmental radioactivity. Fourteen lake waters were collected from different six lakes around Van (Turkey) to determine U-238, Rn-222 and total alpha and total beta distributions in 2009. The total alpha and total beta activities were counted by using alpha/beta counter of the multi-detector low background system (PIC-MPC-9604) and the U-238 concentrations were determined by inductively coupled plasma-mass spectrometry (Thermo Scientific Element 2) and radon concentrations were measured with the solid state nuclear track detector technique. The activity concentrations ranging from ND to 0.039 Bq L-1 and from 0.026 to 3.728 Bq L-1 for total alpha and beta, respectively, and uranium concentrations ranging from 0.083 to 3.078 mu g L-1, and radon concentrations varying between 47.80 and 354.86 Bq m(-3) were observed in the lake waters.
Anti-Oxidant Properties of the Seeds of Gundelia Tournefortii L
(Wiley-blackwell, 2015) Sahin, S.; Coruh, N.; Ozgokce, F.
The Association of Visfatin Levels With Metabolic Parameters and Inflammation in Diabetic Nephropathy
(Yuzuncu Yil Universitesi Tip Fakultesi, 2020) Sakin, A.; Sahin, S.; Behlul, A.; Sumnu, A.; Gursu, M.; Sakin, A.; Ozturk, S.
To investigate the visfatin levels at the stages of diabetic nephropathy(DNP), changes in visfatin levels according to stages of DNP, and the association of visfatin levels with other anti-inflammatory parameters including high sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), and tumor necrosis factor alpha(TNFα). Patients were divided into 4 groups based on the glomerular filtration rate (GFR) and albuminuria as follows; Group I: Albuminuria<30 mg per day and GFR>60ml/min, Group II:albuminuria 30 to 300 mg per day and GFR>60ml/min, Group III:albuminuria>300mg per day and GFR>60ml/min, and Group IV: Albuminuria>300 mg per day and GFR<60 ml/min. Of the 141 patients included in the study, 83(58.8%) were female. The mean age of patients was 55.3±8.2 years. Microalbuminuria was found to be 10.1±9.8 mg per day in group I, 89.4±68.2 mg per day in group II, 525.1±280.7 mg per day in group III, and 1034±1893 mg per day in group IV (p<0.001). When the correlation analysis was repeated separately in each group, there was a positive correlation between Visfatin and IL-6 levels in only group III (r=0.926; p<0.001). When the patients in group III and IV were combined in a single group and considered as macro-albuminuric, multivariate analysis showed that visfatin had a positive correlation with IL-6 (r=0.380, p=0.006) In this study, we could not determine any association between visfatin levels and other anti-inflammatory markers (IL-6, TNFα, and hsCRP). However, we found a close relationship between visfatin levels and IL-6 which is one of the most important markers of inflammation in diabetic patients with overt nephropathy, namely macro-albuminuric patients. © 2020, Yuzuncu Yil Universitesi Tip Fakultesi. All rights reserved.
Chemoradiotherapy Followed by Surgery Versus Observation in Esophageal Squamous Cell Carcinoma
(Zerbinis Publications, 2021) Sakin, A.; Sahin, S.; Aldemir, M.N.; Iliklerden, U.H.; Kotan, M.C.
Purpose: We aimed to examine the effect of esophagectomy after chemoradiotherapy (CRT) or non-surgical follow-up after CRT in patients with locally advanced esophageal squamous cell carcinoma (ESCC). Methods: A total of 653 patients under follow-up for locally advanced ESCC between 2010-2019 were reviewed for enrollment. Patients with no distant metastasis at the time of diagnosis who underwent esophagectomy or were taken under observation following CRT were included in the study. Overall, 127 eligible patients were included, 55 of whom were male (43.3%) and 72 female (56.7%). Results: After CRT, 59 patients (53.5%) had undergone surgery and 68 (46.5%) were taken under observation. Median disease-free survival (mDFS) was not reached in the group that underwent surgery and was 13 months in the observation group (p<0.001). Median overall survival (mOS) was significantly longer in the operated group (p=0.006). There was no statistically significant difference in DFS and OS between patients who underwent surgery and those included in the observation group after achieving clinical and pathological complete response following CRT (p=0.119, p=0.699, respectively). The multivariate analysis identified surgery and increased CRT response as the factors that affect DFS (p=0.042, p<0.001, respectively). Conclusion: In this study, surgery provided no additional benefit on survival in locally advanced ESCC patients with complete response while prolonged survival was observed in those without complete response. © 2021 Zerbinis Publications. All rights reserved.
The Effect of Different Treatment Modalities on Survival in Elderly Patients With Locally Advanced Non-Small Cell Lung Cancer
(Taylor & Francis Ltd, 2021) Sakin, A.; Sahin, S.; Atci, M. M.; Sakin, A.; Yasar, N.; Geredeli, C.; Cihan, S.
Purpose: The aim of this study is to investigate the effect of treatment modalities on survival among unoperat ed and locally-advanced non-small cell lung cancer (NSCLC) patients aged 70 years and older, representing real-life data. Methods: From 2005 through 2017, medical records of 2259 patients with lung cancer from Okmeydani Training and Research Hospital-Istanbul/Turkey were reviewed retrospectively. Patients with locally advanced NSCLC >= 70 years of age who did not undergo surgery for lung cancer were reviewed. In total, 130 patients were eligible for the final analysis. Patients were stratified into four groups as: chemotherapy (CT), concurrent chemoradiotherapy (cCRT), sequential chemoradiotherapy (sCRT), and radiotherapy (RT) only. Results: Of the 130 patients included in the analysis; CT, cCRT, sCRT, and RT only were applied to 25(19.2%), 30(23.1%), 31(23.8%), and 44(33.8%) patients, retrospectively. Twelve (9.2%) patients were female. Median age was 72 years (range, 70-88). Sixty (46.2%) patients had stage IIIA disease and 70(53.8%) patients had stage IIIB disease. Median progression-free survival(mPFS) in patients treated with CT, cCRT, sCRT, and RT were 8.0, 15, 10, and 9.0 months, respectively(p = 0.07). Corresponding median overall survival (mOS) were 10, 33, 20, and 15 months (p = 0.04). In multivariate analysis, stage IIIB disease [hazard ratio (HR), 2.8], ECOG-PS 2(HR, 2.10), and ECOG-PS 3-4(HR, 5.13) were found to be the negative factors affecting survival, while cCRT (HR, 0.45) and sCRT (HR, 0.50) were the independent factors associated with better survival. Conclusion: This study showed that the use of combined treatment modality was associated with better survival in elderly patients with locally advanced NSCLC, with the greatest survival observed in patients treated with cCRT. We therefore suggest that cCRT, when feasible, should be strongly considered in locally advanced NSCLC patients 70 years and over. (c) 2019 Sociedade Portuguesa de Pneumologia. Published by Elsevier Espana, S.L.U. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/).
The Effect of Obesity on Response To Neoadjuvant Therapy in Locally Advanced Gastric Cancer
(Asian Pacific Organization for Cancer Prevention, 2020) Sakin, A.; Sahin, S.; Sakin, A.; Aldemir, M.N.; Bayram, I.; Kotan, C.
Introduction: The effect of obesity on response to neoadjuvant chemotherapy (NACT) remains unknown. We aimed to investigate the effect of obesity on response to NACT and survival in locally-advanced gastric cancer (GC). Methods: From 2010 to 2019, 142 GC patients with clinical stage III disease who underwent curative surgery after NACT were enrolled. Patients were divided into 3 groups according to body mass index (BMI) as follows; BMI < 25 kg/m2, BMI = 25-30 kg/m2, and BMI > 30 kg/m2. The Mandard tumor regression grading system was used for tumor regression grade (TRG). Results: Of the 142 GC patients, 45(31.7%) were female. The median age was 58 years. BMI was < 25 kg/m2 in 60 (42.3%) patients, 25-30 kg/m2 in 44 (31%) patients, and > 30kg/m2 in 38 (26.8%) patients. The numbers of patients with TRGI-II, TRGIII, and TRGIV-V were 35 (24.6%), 44 (31%), and 63 (44.4%), respectively. There was no statistically significant difference among BMI groups in terms of disease-free survival (DFS) and overall survival (OS) (p = 0.919 and p = 0.398, respectively). According to TRG groups; mDFS was 46 months in TRG I-II, 28 months in TRG III, and 18 months in TRG IV-V (p<0.001). In multivariate analysis, presence of perineural invasion and lymphovascular invasion were the factors affecting TRG. Conclusion: In our study, we found that pre-treatment obesity did not affect the TRG in clinical stage III GC patients. However, a better TRG status was associated with improved survival. © 2020 Asian Pacific Organization for Cancer Prevention.
Insar Analysis of Ayvacik 2017 (Mw 5.3) Earthquake Swarm (Canakkale, Nw-Turkey)
(International Society for Photogrammetry and Remote Sensing, 2019) Abdikan, S.; Imamoglu, M.; Alasag, T.; Toker, M.; Kutoglu, S.H.; Sahin, S.
In this study, the deformation of Ayvacik Canakkale earthquake and aftershocks of 5.3 (Mw), which were observed on 6 February 2017 in Gulpinar Ayvacik and felt from the surrounding cities, were analyzed by InSAR and strain reduction technique. The earthquake is occurred at the Biga peninsula which is located at the south segment of North Anatolian Fault zone. The first shock (Ml Combining double low line 4.8) started on 14 January 2017 in the region, and after the second shock (Ml Combining double low line 5.4) on February 6, 2017, seismic storm continued with the large and small earthquakes. It was seen that 31 of these earthquakes have a size of 4 and above and occurred on the Tuzla fault. Since classical geodetic methods are not performed regularly and frequently, and are spatially provide point-based displacements, they are often insufficient to monitor sudden earthquakes. For this purpose, the deformation values were obtained along the line of sight (LOS) direction of Synesthetic Aperture Radar (SAR) sensor using Differential Interferometric SAR (DInSAR) method. For the geophysical analysis coulomb technique was applied and the continuity of the changes in the sea is determined. © Authors 2019.