Exercise-Induced Right Ventricular Outflow Tract Tachycardia in a Patient with Isolated Left Ventricular Noncompaction

Isolated left ventricular noncompaction is a hereditary cardiomyopathy in which a variety of supraventricular and ventricular arrhythmias could be observed. We report a patient with exercise-induced ventricular tachycardia with left bundle branch block morphology that had characteristics of an idiopathic ventricular tachycardia who was subsequently diagnosed as left ventricular noncompaction. Successful remission of arrhythmia was ensured after the introduction of oral beta-blocker therapy

Congenital absence of the pericardium: A rare cause of right ventricular dilatation and levoposition of the heart

Congenital absence of the pericardium is a rare cardiac defect with variable clinical presentations and is usually discovered incidentally. The pathology may lead to serious complications such as incarceration of cardiac tissue, myocardial ischemia, aortic dissection or valvular insufficiency. Diagnosis is not difficult so long as some tips are remembered. We present the cases of two patients with congenital absence of left pericardium

Clinical presentation, diagnosis and management of acute mitral regurgitation following acute myocardial infarction

Acute mitral regurgitation (MR) is a frequent complication of acute myocardial infarction, with a variable presentation depending on the severity of MR and the integrity of the subvalvular apparatus. While most cases are asymptomatic or have mild dyspnea, rupture of chordae tendinea or papillary muscles are catastrophic complications that may rapidly lead to cardiogenic shock and death. Despite the presence of pulmonary edema and/or cardiogrenic shock, the murmur of acute MR is usually subtle due to rapid equalization of left atrial and left ventricular pressure gradient, and therefore misleading. Echocardiography is the definite diagnostic modality, allowing quantification of the severity of MR and the structural abnormalities within the subvalvular apparatus. Severe MR accompanied by rupture of chordae or papillary muscles should be managed with temporary stabilization with medical treatment or with mechanical circulatory support, with subsequent surgical intervention to repair or replace the valve

Immünohistochemical determination of aB-crystallin distribution in the dog central nervous system

Polipeptid yapısında olan aB-Kristallin, lensin ana bileşenlerinden multimerik protein a-kristallin iki alt ünitesinden (aA ve aB) birisidir. aB-Kristallin, moleküler şaperon ve ısı şok proteini olarak protein katlanmalarındaki yanlışları önler ve anti-apoptotik özellikleri vardır. Bu çalışmada, aB-kristallinin köpek merkezi sinir sistemi (MSS)'ndeki ekspresyonu; beyin, beyincik, bulbus olfaktorius, hipofiz, medulla oblongata, ammon boynuzu, hipotalamus ve servikal omurilikten alınan doku örneklerinde immünohistokimyasal teknikle incelendi. aB-kristallin ekspresyonuna, hipofiz hariç incelenen tüm MSS bölgelerinde glial hücrelerde rastlandı. Nöronlarda ise pozitif reaksiyon gözlenmedi. aB-Kristallin/ 2',3'-siklik nükleotid 3'-fosfodiesteraz (CNPase) ikili immünohistokimyasal boyamada, immünoreaktif glia hücrelerinin CNPase pozitif oligodendrositler oldukları belirlendi ve kristallin immünoreaktivitesine özellikle ak madde ve boz maddenin ak maddeye yakın katmanlarındaki oligodendrositlerde rastlandı. Omurilik beyaz ve boz maddesinde oldukça fazla sayıda aB-kristallin pozitif oligodendrositler saptanırken; ak maddede oldukça sınırlı sayıda aB-kristallin pozitif, CNPase negatif glia hücreleri gözlendi. aB-Kristallin immünoreaktivitesi hücrelerin sitoplazmalarında yoğun, çekirdeklerinde ise daha zayıftı. Bu çalışmada, normal köpek MSS'nde özellikle oligodendrositlerde saptanan aB-kristallin'in, myelin temel proteini gibi oligodendrositler tarafından yoğun olarak sentezlenen fonksiyonel proteinlerin yapısının korunmasında görev alabileceği sonucuna varıldı.aB-Crystallin is one of two subunits of multimeric protein a-crystallin (aAand aB), which is a major component of the lens. As a molecular chaperon and heat shock protein, aB-Crystallin prevents false protein folding and has anti-apoptotic properties. In this study, aB-crystallin expression was investigated in the central nervous system (CNS) using the tissues collected from the cerebrum, cerebellum, olfactory bulb, pituitary gland, medulla oblongata, cornu ammonis, hypothalamus and cervical spinal cord. Except in the pituitary, aB-crystallin immunolocalized in glial cells in all nervous tissues investigated. No immunoreactivity was observed in neurons. In double staining of aB-crystallin and 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase), the immunoreactive glial cells were determined to be CNPase positive as oligodendrocytes. Immunoreactive oligodendrocytes located mainly the in the white matter and the layers of the gray matter adjacent to the white matter. However, the spinal cord had numerous aB-kristallin positive oligodendrocytes both in the white and gray matters. In the white matter of the spinal cord, a limited number of glial cells were positive for aB-crystallin, but negative for CNPase. aB-Crystallin immunoreactivity was weak in cytoplasm but very light in the nucleus. As observed in oligodendrocytes of normal dog CNS tissues, aB-crystallin may have roles in anti-apoptotic process of oligodendrocytes and prevention false folding of proteins such as myelin basic protein, which is synthesized intensively by oligodendrocytes

Taşıt savrulma dinamiği kontrol sistemlerinde zaman gecikmesi etkisinin zaman gecikmesi gözleyicisi kullanılarak telafi edilmesi

Zaman gecikmesi kontrol sistemleri tasarımında dikkate alınması gereken sistemin performansını azaltan ve en kötü durumda da sistemi kararsız yapan etkenlerden birisidir. Zaman gecikmesi telafisi için literatürde pek çok yöntem önerilmiştir. Bunlardan en yaygın olarak kullanılanı Smith tahmincisidir. Smith tahmincisi kolaylıkla uygulanabilse de tahmincinin kullandığı zaman gecikmesi modeli ile sistemdeki gerçek zaman gecikmesi farklılaştıkça gecikme telafisi performansı düşmektedir. Bu metodun alternatifi olarak zaman gecikmesi gözleyicisi önerilmiş ve literatürde daha önce bilateral teleoperasyon sistemlerine, robotik manipülatörlere ve iletişim ağı tabanlı yürüyüş şekli rehabilitasyon cihazlarına uygulanmıştır. Bu çalışmada ise zaman gecikmesi gözleyicisinin taşıt savrulma dinamiği kontrolüne uygulanması ele alınmıştır. Zaman gecikmesi gözleyicisinin performansı zamanla değişen gecikmeler için çeşitli simülasyon çalışmalarıyla test edilmiş, ayrıca sonuçlar Smith tahmincisiyle karşılaştırılmıştır

A Comperative Study on Novel Machine Learning Algorithms for Estimation of Energy Performance of Residential Buildings

3rd International Istanbul Smart Grid Congress and Fair (ICSG) -- APR 29-30, 2015 -- Istanbul, TURKEYGUVENC, Ugur/0000-0002-5193-7990; sonmez, yusuf/0000-0002-9775-9835; kahraman, hamdi/0000-0001-9985-6324WOS: 000379385200002This study aims to improve the energy performance of residential buildings. heating load (HL) and cooling load (CL) are considered as a measure of heating ventilation and air conditioning (HVAC) system in this process. In order to achive an effective estimation, hybrid machine learning algorithms including, artificial bee colony-based k-nearest neighbor (abc-knn), genetic algorithm-based knn (ga-knn), adaptive artificial neural network with genetic algorithm (ga-ann) and adaptive ann with artificial bee colony (abc-ann) are used. Results are compared classical knn and ann methods. Thence, relations between input and target parameters are defined and performance of well-known classical knn and ann is improved substantialy

Effect of renal function on the prognostic importance of chloride in patients with heart failure

Hypochloremia has recently gained interest as a potential marker of outcomes in patients with heart failure (HF). The exact pathophysiologic mechanism linking hypochloremia to HF is unclear but is thought to be mediated by chloride-sensitive proteins and channels located in kidneys. This analysis aimed to understand whether renal dysfunction (RD) affects the association of hypochloremia with mortality in patients with HF. Using data from a nationwide registry, 438 cases with complete data on serum chloride concentration and 1-year survival were included in the analysis. Patients with an estimated glomerular filtration rate of <60 mL/min/m2 at baseline were accepted as having RD. Hypochloremia was defined as a chloride concentration <96 mEq/L at baseline. For HF patients without RD at baseline, patients with hypochloremia had a significantly higher 1-year all-cause mortality than those without hypochloremia (41.6% vs 13.0%, log-rank p < 0.001) and the association remained significant after multivariate adjustment (odds ratio (OR): 2.55, 95% confidence interval (CI): 1.25-5.21). The evidence supporting the association was very strong in this subgroup (Bayesian Factor (BF)10: 48.25, log OR: 1.56, 95% CI: 0.69-2.43). For patients with RD at baseline, there was no statistically significant difference for 1-year mortality for patients with or without hypochloremia (36.3% vs 29.7, log-rank p = 0.35) and there was no evidence to support an association between hypochloremia and mortality (BF10: 1.18, log OR :0.66, 95% CI: -0.02 to 1.35). In patients with HF, the association between low chloride concentration and mortality is limited to those without RD at baseline

Exploring the Effect of Distribution Methods on Meta-Heuristic Searching process

2017 International Conference on Computer Science and Engineering (UBMK) -- OCT 05-08, 2017 -- Antalya, TURKEYGUVENC, Ugur/0000-0002-5193-7990; sonmez, yusuf/0000-0002-9775-9835; kahraman, hamdi/0000-0001-9985-6324WOS: 000426856900069In this study, the effect of distributions of solution candidates on the problem space in the meta-heuristic search process and the performance of algorithms has been investigated. For this purpose, solution candidates have been created with random and gauss (normal) distributions. Search performance is measured separately for both types of distribution of algorithms. The performances of the algorithms have been tested on the most popular and widely used benchmark problems. Experimental studies have been conducted on the most recent meta-heuristic search algorithms. It has been seen that the search performance of algorithms varies considerably depending on the method of distribution. In fact, better results were obtained than the distribution methods used in the original versions of the algorithms. Algorithms have revealed their abilities in terms of neighborhoods searching, getting rid of local minimum traps and speeding up searches.IEEE Adv Technol Human, Istanbul Teknik Univ, Gazi Univ, Atilim Univ, TBV, Akdeniz Univ, Tmmob Bilgisayar Muhendisleri Odas