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Article İnsan Kafasındaki Dokuların Öziletkenliklerin Kestirimi İçin Kullanılan İstatistiksel Kısıtlı Minimum Ortalama Hatalar Karesi Algoritmasının Kaynak Yerelleştirimine Etkisi(2012) Şengül, Gökhan; Baysal, UğurEEG ve/veya MEG ölçümleri verildiğinde, insan beynindeki aktif kaynakların bulunması\"EEG/MEG biyoelektromanyetik ters problemi\", \"aktivite kaynağının belirlenmesi\" ya da\"kaynak yerelleştirimi\" (source localization) olarak tanımlanır. Tipik bir kaynak yerelleştirimisistemi EEG/MEG ölçümlerinin yanısıra hastanın/deneğin kafasına ait geometri bilgisine,elektriksel kaynak hakkındaki ön bilgiye, ölçüm elektrotlarının sayısına ve bu elektrotların üçboyutlu uzaydaki konumuna ve kafa modelinde yer alan dokularınöziletkenliklerine/özdirençlerine ihtiyaç duyar. Bu çalışmada insan kafasındaki dokularınöziletkenliklerini kestirmek için daha önce önerilen İstatistiksel Kısıtlı Minimum OrtalamaHatalar Karesi algoritmasının, öziletkenlik kestirimindeki başarımı benzetim çalışmaları ilehesaplanmış ve kaynak yerelleştirimine etkisi araştırılmıştır. Beyin, kafa tası ve kafaderisinden oluşan üç kompartımanlı gerçekçi bir kafa modeli kullanılarak yapılan benzetimçalışmalarında 100 farklı öziletkenlik değeri kestirilmeye çalışılmış ve kestirim hataları kafaderisi için ortalamada %23, kafatası için % 40 ve beyin için de %17 olarak hesaplanmıştır.Çalışmanın ikinci bölümünde ise literatürde verilen ortalama öziletkenlik değerlerikullanıldığında ve önerilen algoritma ile kestirilen öziletkenlik değerleri kullanıldığındaortaya çıkan kaynak yerelleştirimi hataları yine benzetim çalışmaları ile araştırılmıştır.Çalışma sonunda literatürde verilen ortalama öziletkenlik değerleri kullanıldığında 10,1 mmkaynak yerelleştirimi hatası bulunurken önerilen algoritma ile kestirilen öziletkenlik değerlerikullanıldığında ise bu hata 2,7 mm'ye inmiştir. Burada bulunan sonuçlara göre İ.K.M.O.H.K.algoritması ile kestirilen doku öziletkenlikleri kullanıldığında kaynak yerelleştirimi konumhatasında ortalama öziletkenlik kullanılması durumuna göre %73,07'lik azalmagörülmektedir. Sonuç olarak kaynak yerelleştirimi uygulamalarında İ.K.M.O.H.K. algoritmasıile kişiye özgü olarak elde edilen doku öziletkenliklerini kullanmak, ortalama öziletkenlikkullamaya kıyasla hata oranlarını azalttığı sonucuna varılabilir.Article Citation - WoS: 13Citation - Scopus: 13Evaluation of procedural and clinical outcomes of transcatheter aortic valve implantation: A single-center experience(Kare Publ, 2020) Karaduman, Bilge Duran; Kayaoğlu, Hüseyin Ayhan; Keleş, Telat; Bozkurt, Engin; Ayhan, HuseyinObjective: Transcatheter aortic valve implantation (TAVI) is an established alternative to surgical aortic valve replacement. Our study aimed to evaluate the implementation of TAVI at our large-volume center, having an all-comer patient population with short and long-term follow-ups. Methods: This retrospective, single-center analysis included 556 consecutive patients with symptomatic severe aortic stenosis (AS) who underwent TAVI between July 2011 and December 2019. Results: The mean age of the entire population was 77.6±7.9 years, and 54.9% were women. The Society of Thoracic Surgeons (STS) mean score of the cohort was 6.0%±3.5%. The balloon-expandable valve (Sapien XT, Sapien 3; Edwards Lifesciences, Irvine, California) was the most frequently used valves in this cohort (94.6%). Transfemoral access was used in 96.3% of patients. Implantation success was achieved in 96.6% of cases. During the TAVI procedure, 7.2% of patients required permanent pacemaker implantation, with 37.5% in the Lotus valve group needing the most permanent pacemakers. The mean length of hospital stay for the entire cohort was 4.5±2.3 days. Overall, 22 (3.9%) in-hospital deaths occurred before hospital discharge. The mean follow-up period was 15.1±14.9 months for all patients, and a significant improvement was noted in all echocardiographic parameters and functional capacity. Paravalvular leak (PVL) was documented in 18.9% patients, mild in 17.9%, and moderate in 1% at discharge. No cases with severe PVL, necessitating additional procedures. The multiple logistic regression analysis revealed that sex, STS score, baseline SYNTAX score, bicuspid valve morphology, common femoral artery diameter, and post-TAVI PVL were independent predictors of overall mortality. Conclusion: To our knowledge, this study, which is the largest single-center real-world experience of TAVI in Turkey, demonstrated low complication rates with favorable short- and mid-term THV performance in patients undergoing TAVI.Article Citation - WoS: 6Citation - Scopus: 6Covid-19 Infection in Peritoneal Dialysis Patients: \ra Comparative Outcome Study With Patients on \rhemodialysis and Patients Without Kidney Disease(Aves, 2022) Kazancıoğlu, Rümeyza; Ozturk, Savas; Turgutalp, Kenan; Gürsu, Meltem; Arıcı, Mustafa; Oruç, Ayşegül; Ateş, Kenan; Odabas, Ali Riza; Bek, Sibel GökçayObjectives: There is limited data about coronavirus disease-19 (COVID-19) characteristics and results in peritoneal dialysis \r(PD) patients. This study aimed to investigate the characteristics and outcomes among PD patients and compare them with \rmatched hemodialysis (HD) patients and a control group without kidney disease.\rMethods: We included 18 PD patients and consecutive age- and gender-matched 18 HD and 18 patients without kidney \rdisease (control group) registered into the Turkish Society of Nephrology database including 1301 COVID-19 patients. We \rcompared demographic, clinical, radiological, laboratory data, and outcomes namely intensive care unit (ICU) admission, \rmechanical ventilation, mortality, and composite outcome (death and/or ICU admission).\rResults: ICU admission, mechanical ventilation, and mortality rates in PD patients (27.8%, 22.2%, and 22.2%, respectively) \rand the HD group (16.7%, 11.1%, and 16.7%, respectively) were higher than the control group (11.1%, 11.1%, and 5.6%, \rrespectively), but intergroup comparison did not reveal difference. A total of 11 (20.3%) patients had composite outcome \r(6 PD patients, 3 HD patients, and 2 patients in the control group). In Cox regression analysis, higher age and higher CRP level were related to increased risk of composite outcome. Adjusted rate of composite outcome in PD group was significantly higher than \rthe control group (P = .050). This rate was similar in HD and control groups (P = .30).\rConclusions: Combined in-hospital mortality and/or ICU admission of PD patients with COVID-19 was significantly higher than the control \rpatients. There is a need for careful surveillance of PD patients for infection signs and prompt treatment of COVID-19.Article Citation - Scopus: 5Real-World Data From Turkey: Is Sofosbuvir/Ledipasvir With or Without Ribavirin Treatment for Chronic Hepatitis C Really Effective?(AVES, 2021) Demirtürk,N.; Aygen,B.; Çelik,İ.; Mıstık,R.; Akhan,S.; Barut,Ş.; Doğan,N.; Karakeçili, Faruk; Asan, Ali; Özel, Selcan Arslan; Ersöz, Gülden; Yıldız, Orhan; Şimşek, Sümeyra; Tarakçı, HüseyinBackground: In this study, we aimed to investigate the efficacy and safety of sofosbuvir-based therapies in the treatment of chronic hepatitis C in real-world clinical practice. Methods: Data from patients with chronic hepatitis C treated with SOF/LDV ± RBV or SOF/RBV in 31 centers across Turkey between April 1, 2017, and August 31, 2018, were recorded in a nationwide database among infectious disease specialists. Demographics, clinical, and virological outcomes were analyzed. Results: A total of 552 patients were included in the study. The mean age of the patients was 51.28 ± 14.2, and 293 (55.8%) were female. The majority had HCV genotype 1b infection (65%), 75.04% of the patients underwent treatment, and non-cirrhosis was present at baseline in 381 patients (72.6%). SOF/LDV ± RBV treatment was given to 477 patients and 48 patients received SOF/RBV according to HCV genotype. The total SVR12 rate was 99% in all patients. Five patients experienced disease relapse during the study and all of them were genotype 2. In patients infected with HCV GT2, SVR12 was 77.3%. SVR was 100% in all patients infected with other HCV genotypes. All treatments were well tolerated by patients without causing severe adverse events. Side effects and side effects-associated treatment discontinuation rates were 28.2% and 0.4%, respectively. Weakness (13.7%) was the common side effect. Conclusion: The present real-world data of 525 patients with HCV genotypes 1, 1a, 1b, 3, 4, and 5 who underwent SOF/LDV ± RBV treatment in Turkey demonstrated a high efficacy and safety profile. HCV GT2 patients should be treated with more efficacious treatment. © Copyright 2021 by The Turkish Society of Gastroenterology • Available online at turkjgastroenterol.orgArticle Citation - WoS: 3Citation - Scopus: 5Investigation of the Effect of Hyperthyroidism on Endoplasmic Reticulum Stress and Transient Receptor Potential Canonical 1 Channel in the Kidney(Tubitak Scientific & Technological Research Council Turkey, 2021) Aykanat, Nuriye Ezgi Bektur; Şahin, Erhan; Kaçar, Sedat; Bağcı, Rıdvan; Karakaya, Şerife; Dönmez, Dilek Burukoğlu; Şahintürk, Varol; Bektur Aykanat, Nuriye Ezgi; Burukoğlu Dönmez, Dilek; Bektur, EzgiBackground/aim: Hyperthyroidism is associated with results in increased glomerular filtration rate as well as increased renin-angiotensin-aldosterone activation. The disturbance of Ca2+ homeostasis in the endoplasmic reticulum (ER) is associated with many diseases, including diabetic nephropathy and hyperthyroidism. Transient receptor potential canonical 1 (TRPC1) channel is the first cloned TRPC family protein. Although it is expressed in many places in the kidney, its function is uncertain. TRPC1 is involved in regulating Ca2+ homeostasis, and its upregulation increases ER Ca2+ level, activates the unfolded protein response, which leads to cellular damage in the kidney. This study investigated the role of TRPC1 in the kidneys of hyperthyroid rats in terms of ER stress markers that are glucose-regulated protein 78 (GRP78), activating transcription factor 6 (ATF6), (protein kinase R (PKR)-like endoplasmic reticulum kinase) (PERK), Inositol-requiring enzyme 1 (IRE1). Materials and methods: Twenty male rats were assigned into control and hyperthyroid groups (n = 10). Hyperthyroidism was induced by adding 12 mg/L thyroxine into the drinking water of rats for 4 weeks. The serum-free T3 and T4 (fT3, fT4), TSH, blood urea nitrogen (BUN), and creatinine levels were measured. The histochemical analysis of kidney sections for morphological changes and also immunohistochemical and western blot analysis of kidney sections were performed for GRP78, ATF6, PERK, IRE1, TRPC1 antibodies. Results: TSH, BUN, and creatinine levels decreased while fT3 and fT4 levels increased in the hyperthyroid rat. The morphologic analysis resulted in the capillary basal membrane thickening in glomeruli and also western blot, and immunohistochemical results showed an increase in TRPC1, GRP78, and ATF6 in the hyperthyroid rat (p < 0.05). Conclusion: In conclusion, in our study, we showed for the first time that the relationship between ER stress and TRPC1, and their increased expression caused renal damage in hyperthyroid rats.Key words: Hyperthyroidism, endoplasmic reticulum (ER) stress, transient receptor potential canonical 1 (TRPC1), kidney, ratArticle Citation - WoS: 1Citation - Scopus: 1Karotis Arter Stentlemesinin Etkinliği ve Güvenliği: Tek Merkez Deneyimi(Kare Publ, 2020) Karaduman, Bilge Duran; Karaduman, Bilge Duran; Ayhan, Hüseyin; Ayhan, Hüseyin; Keles, Telat; Bozkurt, Engin; Karaduman, Bilge Duran; Ayhan, HüseyinAmaç: İnternal karotis arterdeki orta ve şiddetli darlıklar tüm inmelerin %10–15’ine neden olmaktadır. Bu çalışmada, üçüncü basamak bir referans merkezde karotis arter stentlemesinin (KAS) güvenliğini ve kısa dönem etkinliğini değerlendirmeyi amaçladık. Yöntemler: Üçüncü basamak merkezimizde Ocak 2017 ile Mayıs 2018 arasında KAS uygulanan hastalar geriye dönük olarak değerlendirildi. KAS uygulanan 145 hasta çalışmaya dahil edildi. Bulgular: Hastaların ortalama yaşı 70.1±8.6 yıl idi ve tüm grubun %75.2’si erkek olup %37.9’unda hipertansiyon mevcuttu. Hastaların 81’i (%55.9) semptomatik, 64’ü (%44.1) asemptomatik olarak gruplandırıldı. Semptomatik hastalarda koroner girişimler daha çok KAS sonrası (%38.9) yapılırken, asemptomatik grupta ise KAS öncesi (%25.9) ve sonrasında (%25.9) benzer oranlarda yapıldığı görüldü ama gruplar arasında istatistiksel fark yoktu. Semptomatik hastalarda (%59.2), asemptomatik hastalarda (%78.7) olduğu gibi distal emboli koruyucu cihaz (EKC), proksimal EKC’ye göre daha fazla kullanıldı. Ancak proksimal EKC, semptomatik hastalarda asemptomatik hastalara kıyasla anlamlı olarak daha fazla kullanıldı. Hastane içi ölüm görülmedi ve tüm popülasyonda 5 (%3.4) hastada inme veya geçici iskemik atak (GİA) gözlendi. Asemptomatik grupta GİA veya inme gözlenmedi, semptomatik grupta 2 hastada (%2.4) inme ve 3 hastada (%3.7) GİA görüldü. Sonuç: Bu çalışma kabul edilebilir komplikasyon oranları ile KAS’ın güvenirliğini ve uygulanabilirliğini ortaya koymuştur. KAS prosedürü, deneyimli girişimciler tarafından optimal tıbbi tedavi altında, agresif risk modifikasyonu ile EKC kullanılarak, uygun hastalarda en az komplikasyonla gerçekleştirilmelidir.Article Morphometry and Geometry of the Formation of Basilar Artery(2019) Akkaşoğlu, Sinem; Aldur, M.; Sargon, Mustafa Fevzi; Çelebioğlu, Emre; Çalışkan, SelmaThe morphometric studies on pathological changes observed in vertebral and basilar arteries are valuable in the diagnosis of many pathological disorders. The purpose of this study was to detect the morphometry and geometry of the intracranial part of vertebral and basilar arteries according to age, sex, and dominance parameters in huge series to contribute to the literature. In the study, the morphometric analysis was performed on 250 healthy patients (133 males, 117 females) by using Computed Tomography (CT) angiography. In 86 cases (34.4%) (47 males, 39 females), the basilar artery coursed straight to the right side. One hundred forty-five patients (58%) had left vertebral artery dominance. The diameters of the vessels were higher in males than in females, and there was no relationship between this finding and age. The diameter of the basilar artery at the vertebrobasilar junction was statistically significantly higher than its diameter in the terminal part of the pons. By the aid of vertical axis drawn from the formation point of basilar artery by the union of vertebral arteries, the angles of the right and left vertebral arteries were examined separately. These data will penlight future studies. This is the first study in measuring the angle of basilar artery along its course. The aim this study was to determine the changes that might occur in this angle due to the aging. To our knowledge there is no study examining the morphometry and geometry of the vertebral and basilar arteries together with these detailed parameters separately in the literature.Article Citation - WoS: 9Citation - Scopus: 10Impact of Hospital-Acquired Acute Kidney Injury on Covid-19 Outcomes in Patients With and Without Chronic Kidney Disease: a Multicenter Retrospective Cohort Study(Tubitak Scientific & Technological Research Council Turkey, 2021) Ozturk, Savas; Turgutalp, Kenan; Arıcı, Mustafa; Çetinkaya, Hakkı; Altıparmak, Mehmet Rıza; Aydın, Zeki; Ateş, Kenan; Dolarslan, Mursıde Esra; Seyahi, Nurhan; Yıldız, Alaattın; Bora, FeyzaBackground/aim: Hospital-acquired acute kidney injury (HA-AKI) may commonly develop in Covid-19 patients and is expected to have higher mortality. There is little comparative data investigating the effect of HA-AKI on mortality of chronic kidney disease (CKD) patients and a control group of general population suffering from Covid-19. Materials and methods: HA-AKI development was assessed in a group of stage 3–5 CKD patients and control group without CKD among adult patients hospitalized for Covid-19. The role of AKI development on the outcome (in-hospital mortality and admission to the intensive care unit [ICU]) of patients with and without CKD was compared. Results: Among 621 hospitalized patients (age 60 [IQR: 47–73]), women: 44.1%), AKI developed in 32.5% of the patients, as stage 1 in 84.2%, stage 2 in 8.4%, and stage 3 in 7.4%. AKI developed in 48.0 % of CKD patients, whereas it developed in 17.6% of patients without CKD. CKD patients with HA-AKI had the highest mortality rate of 41.1% compared to 14.3% of patients with HA-AKI but no CKD (p < 0.001). However, patients with AKI+non-CKD had similar rates of ICU admission, mechanical ventilation, and death rate to patients with CKD without AKI. Adjusted mortality risks of the AKI+non-CKD group (HR: 9.0, 95% CI: 1.9–44.2) and AKI+CKD group (HR: 7.9, 95% CI: 1.9–33.3) were significantly higher than that of the non-AKI+non-CKD group. Conclusion: AKI frequently develops in hospitalized patients due to Covid-19 and is associated with high mortality. HA-AKI has worse outcomes whether it develops in patients with or without CKD, but the worst outcome was seen in AKI+CKD patients.Key words: Acute kidney injury, chronic kidney disease, Covid-19, hospitalization, mortalityArticle Main Outcomes of the Diyal-Tr Study: Regional\rdifferences of Mortality and Morbidity in Chronic\rhemodialysis Patients(Aves, 2022) Kızılırmak, Pınar; Ecder, Süleyman Tevfik; Ateş, Kenan; Arıcı, Mustafa; Sezer, Siren; Kaptanoğulları, Hakan; Arınsoy, Selim Turgay; Ecder, Tevfik; Arinsoy, TurgayObjective: Variations in care at national or global level may have an impact on the prognosis of patients on chronic hemodialysis.\rWe aimed to describe regional differences in all-cause mortality or cardiovascular morbidity in chronic hemodialysis\rpatients in Turkey.\rMethods: We enrolled 2461 patients who were initiated chronic hemodialysis in 93 centers in Turkey between January 27,\r2017, and February 09, 2018. We included 2-year follow-up data of 1877 patients in this prospective study. The primary\routcome, the rate of composite endpoint of all-cause mortality or cardiovascular morbidity, was compared between geographical\rregions. Secondary outcomes were the rates of hospitalization and infections.\rResults: In total, 552 patients (29.4%) developed the primary outcome. The highest and lowest rates of primary outcome\roccurred in the Mediterranean (34.5%) and Southeastern (26.5%) & Central Anatolian regions (26.5%), respectively, with no\rsignificant differences across regions (P = .82). Hospitalization events were detected in 377 patients (20.1%). The highest\rrate of hospitalization was detected in the Black Sea region (33.8%), and the lowest (7.6%) in the Southeastern region. The\rregions did not differ in hospitalization rates (P = .88). Infections occurred in 11.3% (n = 212) of the patients. The highest and\rlowest rates of infections occurred in the Aegean (18.2%) and the Southeastern (2.9%) regions, respectively. We detected\rsignificant difference between geographic regions (P = .02).\rConclusions: Our study showed that almost 3 in every 10 chronic hemodialysis patients reached the primary endpoint\rof all-cause mortality/cardiovascular morbidity during the 2 years of follow-up. The occurrence of this outcome does not\rseem to exhibit geographical variation across the country.Article Tip 2 Diyabetli Bireylerde Kardiyovasküler Hastalıklar Risk Faktörleri Bilgi Düzeyi ve Fiziksel Aktivite Seviyelerinin İncelenmesi(2021) Özel, Cemile Bozdemir; Arıkan, Hülya; Dağdelen, Selçuk; Kütükçü, Ebru Çalık; Karadüz, Beyza Nur; Kabakçı, Mevlana Giray; İnce, Deniz İnal; Karadüz-durukan, Beyza Nur; Inal-ınce, DenizAmaç: Tip 2 diyabetli bireylerde fiziksel aktivite kardiyovasküler hastalıklar risk faktörleri açısından önemlidir. Çalışmanın amacı, Tip 2 diyabetli bireylerde kardiyovasküler hastalıklar risk faktörleri bilgi düzeyi ve fiziksel aktivite seviyelerini değerlendirmekti.Yöntem: Çalışmaya 47 tip 2 diyabetli birey (yaş ortalaması: 50,80±5,61 yıl) dahil edildi. Vücut yağı biyoelektrik empedans analizi ile değerlendirildi. Kardiyovasküler hastalıklar risk faktörleri bilgi düzeyi, Kardiyovasküler Hastalıklar Risk Faktörleri Bilgi Düzeyi Ölçeği (0-28) ile değerlendirildi. Koroner arter hastalık risk faktörleri hesaplandı. Fiziksel aktivite seviyeleri yedi gün boyunca üç eksenli akselerometre ile ölçüldü.Bulgular: Kardiyovasküler hastalıklar risk faktörleri bilgi düzeyi ölçeği 20,69±3,86 puandı. Framingham risk skoru 8,85±3,06 olarak kaydedildi. Günlük ortalama adım sayısı 7195±3441,20 adım/gün olarak hesaplandı. Metabolik eşdeğer ile açlık kan glukozu (r=-0.381; p=0,018), vücut kütle indeksi (r=-0,665; p<0,001), bel çevresi (r=-0,381; p=0,018), vücut yağ yüzdesi (r=-0,554; p=0,002) ile ilişkiliydi. Kardiyovasküler hastalıklar bilgi düzeyi ortalamanın üzerinde bulundu. Sonuç: Tip 2 diyabetli bireylerde kardiyovasküler hastalıklar bilgi düzeyi ortalamanın üzerinde olmasına rağmen, bireylerin adım sayıları düşüktü. Tip 2 diyabetli bireyleri fiziksel aktivite konusunda bilinçlendirmeye ve adım sayısının yanı sıra aktivite şiddetine de odaklanarak fiziksel aktiviteyi arttırmaya yönelik uygulamalar amaçlanmalıdır.
