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Öğe Metals and phosphorus in the sediments of streams emptying into the Çanakkale strait (Dardanelles): Spatial distribution, pollution status, risk assessment and source identification(Academic Press Inc Elsevier Science, 2024) Varol, Memet; Tokatli, CemThe & Ccedil;anakkale Strait is exposed to various pollutants due to its strategic location. It is thought that stream inputs may contribute significantly to metal and phosphorus (P) accumulation in the strait. In this study, the spatial distribution, pollution status, ecological risks and possible sources of twelve metals and P in the sediments of seven important streams emptying into the strait were analyzed. The results showed that Zn (226 mg/kg), Ba (67.2 mg/kg) and Pb (10.4 mg/kg) concentrations were higher in the Umurbey Stream due to mining activities, while P concentration (295 mg/kg) was higher in the & Ccedil;anakkale Stream due to both agricultural activities and domestic wastewater discharges. Modified hazard quotient (mHQ), enrichment factor (EF) and contamination factor (Cf) values revealed that Zn and Pb showed high and moderate contamination in the US3 and US4 sampling sites of the Umurbey Stream, respectively. Similarly, P showed moderate contamination in the & Ccedil;S3 site of the & Ccedil;anakkale Stream. Nemerow pollution index (NPI) showed that the US3 (2.41) and US4 (4.28) sites of the Umurbey Stream were slightly and moderately polluted, respectively. Toxic risk index (TRI) values demonstrated that the sediments in only the US4 site (5.17) of the Umurbey Stream may pose a low toxic risk due to high Zn content. Similarly, based on comparison results with sediment quality guidelines (SQGs), it was found that high Zn content may lead to adverse effects on sediment-dwelling organisms in the US4 site. In addition, the PECquotient value in the US4 site exceeded 0.5, confirming the finding that the sediments in this site could be toxic to benthic organisms. Finally, correlation, cluster and factor analyzes were used to determine possible sources of elements. Mining activities, natural sources and mixed sources (agricultural activities and natural sources) were identified as the main sources of elements in the sediments of the streams. This study can provide an important reference for evaluating stream sediment pollution and managing marine pollution.Öğe Revisiting Classical 3?-hydroxysteroid Dehydrogenase 2 Deficiency: Lessons from 31 Pediatric Cases(Endocrine Soc, 2020) Guran, Tulay; Kara, Cengiz; Yildiz, Melek; Bitkin, Eda C.; Haklar, Goncagul; Lin, Jen-Chieh; Keskin, MehmetContext: The clinical effects of classical 3 beta-hydroxysteroid dehydrogenase 2 (3 beta HSD2) deficiency are insufficiently defined due to a limited number of published cases. Objective: To evaluate an integrated steroid metabolome and the short- and long-term clinical features of 3 beta HSD2 deficiency. Design: Multicenter, cross-sectional study. Setting: Nine tertiary pediatric endocrinology clinics across Turkey. Patients: Children with clinical diagnosis of 3 beta HSD2 deficiency. Main Outcome Measures: Clinical manifestations, genotype-phenotype-metabolomic relations. A structured questionnaire was used to evaluate the data of patients with clinical 3 beta HSD2 deficiency. Genetic analysis of HSD3B2 was performed using Sanger sequencing. Novel HSD3B2 mutations were studied in vitro. Nineteen plasma adrenal steroids were measured using LC-MS/MS. Results: Eleven homozygous HSD3B2 mutations (6 novel) were identified in 31 children (19 male/12 female; mean age: 6.6 +/- 5.1 yrs). The patients with homozygous pathogenic HSD3B2 missense variants of > 5% of wild type 3 beta HSD2 activity in vitro had a non-salt-losing clinical phenotype. Ambiguous genitalia was an invariable feature of all genetic males, whereas only 1 of 12 female patients presented with virilized genitalia. Premature pubarche was observed in 78% of patients. In adolescence, menstrual irregularities and polycystic ovaries in females and adrenal rest tumors and gonadal failure in males were observed. Conclusions: Genetically-documented 3 beta HSD2 deficiency includes salt-losing and non-salt-losing clinical phenotypes. Spared mineralocorticoid function and unvirilized genitalia in females may lead to misdiagnosis and underestimation of the frequency of 3 beta HSD2 deficiency. High baseline 17OHPreg to cortisol ratio and low 11-oxyandrogen concentrations by LC-MS/MS unequivocally identifies patients with 3 beta HSD2 deficiency.Öğe On the behavior of single-particle dynamic properties of liquid Hg and other metals(Amer Inst Physics, 2008) Gonzalez, Luis E.; Gonzalez, David J.; Calderin, Lÿzaro; Sengul, SedatRecent experiments and classical molecular dynamics simulations performed on liquid Hg near melting have suggested the existence of two processes with different time scales in its single-particle dynamics. We report a study of this system by using ab initio molecular dynamics simulations, which recover the same kind of behavior, and we analyze it in terms of a theoretical approach, which clarifies its origin. We show that the previous interpretation has been induced by the unphysical extension of the diffusive model to short times. Moreover, we also find that quite different liquid metals, such as Si and Mg, also exhibit a similar behavior as Hg, with the only difference being in the time scales involved due to the different masses and interactions.Öğe Cemiplimab monotherapy for first-line treatment of advanced non-small-cell lung cancer with PD-L1 of at least 50%: a multicentre, open-label, global, phase 3, randomised, controlled trial(Elsevier Science Inc, 2021) Sezer, Ahmet; Kilickap, Saadettin; Gumus, Mahmut; Bondarenko, Igor; Ozguroglu, Mustafa; Gogishvili, Miranda; Turk, Haci M.Background We aimed to examine cemiplimab, a programmed cell death 1 inhibitor, in the first-line treatment of advanced non-small-cell lung cancer with programmed cell death ligand 1 (PD-L1) of at least 50%. Methods In EMPOWER-Lung 1, a multicentre, open-label, global, phase 3 study, eligible patients recruited in 138 clinics from 24 countries (aged >= 18 years with histologically or cytologically confirmed advanced non-small-cell lung cancer, an Eastern Cooperative Oncology Group performance status of 0-1; never-smokers were ineligible) were randomly assigned (1:1) to cemiplimab 350 mg every 3 weeks or platinum-doublet chemotherapy. Crossover from chemotherapy to cemiplimab was allowed following disease progression. Primary endpoints were overall survival and progression-free survival per masked independent review committee. Primary endpoints were assessed in the intention-to-treat population and in a prespecified PD-L1 of at least 50% population (per US Food and Drug Administration request to the sponsor), which consisted of patients with PD-L1 of at least 50% per 22C3 assay done according to instructions for use. Adverse events were assessed in all patients who received at least one dose of the assigned treatment. This study is registered with ClinicalTrials.gov, NCT03088540 and is ongoing. Findings Between June 27, 2017 and Feb 27, 2020, 710 patients were randomly assigned (intention-to-treat population). In the PD-L1 of at least 50% population, which consisted of 563 patients, median overall survival was not reached (95% CI 17.9-not evaluable) with cemiplimab (n=283) versus 14.2 months (11.2-17.5) with chemotherapy (n=280; hazard ratio [HR] 0.57 [0.42-0.77]; p=0.0002). Median progression-free survival was 8.2 months (6.1-8.8) with cemiplimab versus 5.7 months (4.5-6.2) with chemotherapy (HR 0.54 [0.43-0.68]; p<0.0001). Significant improvements in overall survival and progression-free survival were also observed with cemiplimab in the intention-to-treat population despite a high crossover rate (74%). Grade 3-4 treatment-emergent adverse events occurred in 98 (28%) of 355 patients treated with cemiplimab and 135 (39%) of 342 patients treated with chemotherapy. Interpretation Cemiplimab monotherapy significantly improved overall survival and progression-free survival compared with chemotherapy in patients with advanced non-small-cell lung cancer with PD-L1 of at least 50%, providing a potential new treatment option for this patient population. Copyright (C) 2021 Elsevier Ltd. All rights reserved.Öğe A New Cornerstone of Education of Authorship and Biomedical Project Design: International Research Interdisciplinary School, Slovakia, 2016(Galenos Publ House, 2016) Inan, Mustafa; Racu, Andrei; Bjelosevica, Marko; Hryniv, Nazarii[Abstract Not Available]Öğe Strain can hide some states Reply(Turkish Soc Cardiology, 2018) Demirkiran, Aykut; Albayrak, Neslihan; Albayrak, Yakup; Zorkun, Cafer Sadik[Abstract Not Available]Öğe Changing the traditional p-value significance threshold to .005 does not decrease the number of statistically significant p-values in observational studies more than in randomised controlled trials(Clinical & Exper Rheumatology, 2021) Oztas, M.; Dincer, Z. T.; Sut, N.; Yazici, H.Oztas, Istanbul University-Cerrahpasa, Cerrahpasa Medical Faculty, Department of Medicine, IUC. Cerrahpasa Tip Fakultesi Yerleskesi, Kocamustafapasa Cd. No: 53 Cerrahpasa, 34098 Fatih/Istanbul, Turkey.Öğe Feature Extraction Using Time-Frequency Analysis for Monophonic-Polyphonic Wheeze Discrimination(IEEE, 2015) Ulukaya, Sezer; Sen, Ipek; Kahya, Yasemin P.The aim of this study is monophonic-polyphonic wheeze episode discrimination rather than the conventional wheeze (versus non-wheeze) episode detection. We used two different methods for feature extraction to discriminate monophonic and polyphonic wheeze episodes. One of the methods is based on frequency analysis and the other is based on time analysis. Frequency analysis based method uses ratios of quartile frequencies to exploit the difference in the power spectrum. Time analysis based method uses mean crossing irregularity to exploit the difference in periodicity in the time domain. Both methods are applied on the data before and after an image processing based preprocessing step. Calculated features are used in classification both individually and in combinations. Support vector machine, k-nearest neighbor and Naive Bayesian classifiers are adopted in leave-one-out scheme. A total of 121 monophonic and 110 polyphonic wheeze episodes are used in the experiments, where the best classification performances are 71.45% for time domain based features, 68.43% for frequency domain based features, and 75.78% for a combination of selected best features.Öğe An unusual foreign body: A pendant(Pakistan Medical Assoc, 2010) Sayhan, Mustafa Burak; Gokdemir, Mehmet Tahir; Kavalci, Cemil[Abstract Not Available]Öğe Antenatal fetal risk assessment by blood-flow velocity waveforms(IEEE-Inst Electrical Electronics Engineers Inc, 2000) Gurgen, F; Guler, N; Varol, F[Abstract Not Available]Öğe Chilaiditi's syndrome(Pakistan Medical Assoc, 2010) Sayhan, Mustafa Burak; Kavalci, Cemil; Bakirci, Tarkan; Gokdemir, Mehmet Tahir[Abstract Not Available]Öğe Sonographic pitfall in diagnosing breast cysts: Pseudomural projections(John Wiley & Sons Inc, 1998) Tenekeci, AN; Pekindil, G[Abstract Not Available]Öğe Treating vitamin D deficiency (VDD) can also play a role in fight against chronic diseases(Pakistan Medical Assoc, 2010) Sayhan, Mustafa Burak; Kavalci, Cemil; Bakirci, Tarkan; Gokdemir, Mehmet Tahir[Abstract Not Available]Öğe Unexpectedly high prevalence of narcolepsy in Sivas(Turkish Assoc Tuberculosis & Thorax, 2006) Ozturk, Levent; Bulut, Erdogan[Abstract Not Available]Öğe Commentary on Viewpoint: REGULATION OF LEPTIN BY HYPOXIA(Amer Physiological Soc, 2008) Ozturk, Levent[Abstract Not Available]Öğe Should Bioprosthetic Valves be Implanted in Patients with Aortic Stenosis having a Low Surgical Risk? A Perspective with Pros and Cons(Galenos Publ House, 2024) Ozkan, Ugur; Gurdogan, Muhammet; Kaya, Caglar; Ari, Hasan[Abstract Not Available]Öğe Sudden death: A case report of hepatocellular carcinoma with tumor thrombus extending into the right atrium(Zerbinis Medical Publ, 2007) Saynak, M.; Ozen, A.; Kocak, Z.; Cosar-Alas, R.; Uzal, C.[Abstract Not Available]Öğe Incidental diagnosis of asymptomatic pericardial effusion in uraemic patient by using 99mTc-MIBI perfusion SPEG(Schattauer Gmbh-Verlag Medizin Naturwissenschaften, 2003) Durmus-Altun, G; Ustun, F; Altun, A; Ustundog, S[Abstract Not Available]Öğe A fat headache(New Zealand Medical Assoc, 2009) Karasalihoglu, Serap; Guzel, Ahmet; Ugurluoglu, Yasemin Kucuk; Unlu, Ercuement[Abstract Not Available]Öğe A splenic injury due to ruptured abdominal aortic aneurysm(Edizioni Minerva Medica, 2007) Gur, O.; Canbaz, S.; Halici, U.; Duran, E.[Abstract Not Available]
