Huseyin Cagatay Yalcin

Qatar University · Biomedical Research Center

Computational Fluid Dynamics (CFD) analysis is widely used to simulate hemodynamics and investigate the biofluid mechanics of different tissue, whole organs, and tissue-medical device interactions. However, CFD simulations are time-consuming and computationally expensive; hence are not readily available and practical for patient-specific time-sensi...

The non-invasive fetal electrocardiogram (fECG) enables easy detection of developing heart abnormalities, leading to a significant reduction in infant mortality and post-natal complications. Due to the overlapping of maternal and fetal R-peaks, the low amplitude of the fECG, systematic and ambient noises, and typical signal extraction methods, such...

Aortic valve defects are among the most prevalent clinical conditions. A severely damaged or non-functioning aortic valve is commonly replaced with a bioprosthetic heart valve (BHV) via the transcatheter aortic valve replacement (TAVR) procedure. Accurate pre-operative planning is crucial for a successful TAVR outcome. Assessment of computational f...

Fetal heart monitoring and early disease detection using non-invasive fetal electrocardiograms (fECG) can help substantially to reduce infant death through improved diagnosis of Coronary Heart Disease (CHD) in the fetus. Despite the potential benefits, non-invasive fECG extraction from maternal abdominal ECG (mECG) is a challenging problem due to m...

Chemicals are at the top of public health concerns and metals have received much attention in terms of toxicological studies. Cadmium (Cd) and mercury (Hg) are among the most toxic heavy metals and are widely distributed in the environment. They are considered important factors involved in several organ disturbances. Heart and brain tissues are not...

An abdominal aortic aneurysm (AAA) is a critical health condition with a risk of rupture, where the diameter of the aorta enlarges more than 50% of its normal diameter. The incidence rate of AAA has increased worldwide. Currently, about three out of every 100,000 people have aortic diseases. The diameter and geometry of AAAs influence the hemodynam...

Congenital heart defects (CHDs) are a leading cause of death in infants under 1 year of age. Prenatal intervention can reduce the risk of postnatal serious CHD patients, but current diagnosis is based on qualitative criteria, which can lead to variability in diagnosis between clinicians. Objectives: To detect morphological and temporal changes in c...

Autoimmune diseases (AD) have emerged as a pandemic in our modern societies, especially after the World War II. In part I, we have reviewed five main diseases and shed light on different aspects from introducing the concept of autoimmunity, the description of the disease's pathogenesis and the diagnosis, the role of antibod-ies as markers for the p...

Autoimmune diseases have emerged as a pandemic in our modern societies, especially after World War II. There are currently more than 80 autoimmune diseases that compromise the lives of millions of patients around the world. There is a variety of factors that are involved in the pathogenesis of autoimmune diseases that vary from environmental factor...

Motile cilia are hair-like microscopic structures which generate directional flow to provide fluid transport in various biological processes. Ciliary beating is one of the sources of cerebrospinal flow (CSF) in brain ventricles. In this study, we investigated how the tilt angle, quantity, and phase relationship of cilia affect CSF flow patterns in...

Wearable sensors have drawn considerable interest in the recent research world. However, simultaneously realizing high sensitivity and wide detection limits under changing surrounding environment conditions remains challenging. In the present study, we report a wearable piezoresistive pressure sensor capsule that can detect pulse rate and human mot...

Purpose This study examines the effect of antihypertensive drugs on ACE2 and Angiotensin II levels in hypertensive COVID-19 patients. Introduction Hypertension is a common comorbidity among severe COVID-19 patients. ACE2 expression can be modulated by antihypertensive drugs such as ACEis and ARBs, which may affect COVID-19's prognosis. BB and CCB...

This chapter provides an introduction to the use of machine learning (ML) for the diagnosis of heart failure (HF). ML is the field responsible for developing methods and tools that can learn and make decisions based on data. The growing number of HF patients and increasing healthcare costs indicate the importance of the early diagnosis of HF for ef...

Heart failure is a life-threatening medical problem which refers to inadequate blood supply to body tissues due to the limited functioning of heart muscles. Heart failure is mostly observed as a chronic disease which requires frequent hospitalizations and emergency healthcare. The globally growing number of heart failure patients and high hospitali...

Collectively known as congenital heart defects (CHDs), cardiac abnormalities at birth are the most common forms of neonatal defects. Being principally responsible for the heart‘s pumping power, ventricles are particularly affected by developmental abnormalities, such as flow disturbances or genomic defects. Hypoplastic Right Heart Syndrome (HRHS) i...

Congenital heart defects (CHDs) affect a wide range of societies with an incidence rate of 1.0–1.2%. These defects initiate at the early developmental stage and result in critical health disorders. Although genetic factors play a role in the formation of CHDs, the occurrence of cases in families with no history of CHDs suggests that mechanobiologic...

Experimental and clinical evidence suggests that diabetic subjects are predisposed to a distinct cardiovascular dysfunction, known as diabetic cardiomyopathy (DCM), which could be an autonomous disease independent of concomitant micro and macrovascular disorders. DCM is one of the prominent causes of global morbidity and mortality and is on a risin...

Abnormality in glucose homeostasis due to hyperglycemia or insulin resistance is the hallmark of type 2 diabetes mellitus (T2DM). These metabolic abnormalities in T2DM lead to cellular dysfunction and the development of diabetic cardiomyopathy leading to heart failure. New antihyperglycemic agents including glucagon-like peptide-1 receptor agonists...

Hypertension is a major risk factor and common comorbidity among severe Coronavirus Disease 2019 (COVID-19) patients. Prominent antihypertensive drugs, such as angiotensin-converting-enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB) can modulate the expression of angiotensin-converting enzyme 2 (ACE2) and may influence COVID-19 progn...

The exhaled breath volatile organic compounds (VOC’s) represent a biosignature with the potential to identify and describe heart failure diseases. Exhaled Breath biomarkers-based diagnosis of heart diseases may be easier and earlier detection than other available techniques. So, this is a review of combining both exhaled breath analysis with cost e...

Over the last decade, there has been a huge demand for health care technologies such as sensors-based prediction using digital health. With the continuous rise in the human population, these technologies showed to be potentially effective solutions to life-threatening diseases such as heart failure (HF). Besides being a potential for early death, H...

Flow-driven hemodynamic forces on the cardiac tissues have critical importance, and have a significant role in the proper development of the heart. These mechanobiological mechanisms govern the cellular responses for the growth and remodeling of the heart, where the altered hemodynamic environment is believed to be a major factor that is leading to...

The SARS-CoV-2 virus utilizes angiotensin converting enzyme (ACE-2) for cell entry andinfection. This enzyme has important functions in the renin-angiotensin aldosterone system topreserve cardiovascular function. In addition to the heart, it is expressed in many tissues includingthe lung, intestines, brain, and kidney, however, its functions in the...

Aortic valve calcification is an important cardiovascular disorder that deteriorates the accurate functioning of the valve leaflets. The increasing stiffness due to the calcification prevents the complete closure of the valve and therefore leads to significant hemodynamic alterations. Computational fluid dynamics (CFD) modeling enables the investig...

With the recent SARS-CoV-2 outbreak, the importance of rapid and direct detection of respiratory disease viruses has been well recognized. The detection of these viruses with novel technologies is vital in timely prevention and treatment strategies for epidemics and pandemics. Respiratory viruses can be detected from saliva, swab samples, nasal flu...

Many patients who suffer from pulmonary diseases cannot inflate their lungs normally as they need Mechanical Ventilation (MV) to assist them. The stress associated with MV can damage delicate epithelium in small airways and alveoli which can cause complications in many cases resulting in Ventilation Induced Lungs injuries (VILI) especially in patie...

The heart is the first functional organ in a developing embryo. Cardiac development continues throughout developmental stages while the heart goes through a serious of drastic morphological changes. Previous animal experiments as well as clinical observations showed that disturbed hemodynamics interfere with the development of the heart and leads t...

Background: Hemodynamics, forces from the flowing blood in the heart, is a major epigenetic factor for heart development. Disturbed hemodynamics were shown to induce cardiac malformations in the embryonic heart. Clinically relevant congenital heart defects (CHDs) can be introduced surgically in the lab by disturbing the hemodynamics, like Hypoplast...

Acute respiratory distress syndrome (ARDS) is an infectious clinical condition in which gas exchange inside the airways and alveoli are disturbed. Fluid filled lungs need to be mechanically ventilated for airway reopening.Ventilation might further damage delicate lung tissue and lead to edema,a phenomenon known as ventilator-induced lung injury VIL...

Background: Cardiovascular diseases (CVDs) are the first cause of death worldwide. Vasolidator agents are used to relax cardiac muscle, but their extremely short half-lifes limit their effectiveness. Sildenafil is such an agent used to relax the blood vessels muscles and increase the blood flow. The conventional drug can lead to serious problems in...

Management of chronic diabetic ulcers remains as a major challenge in healthcare which requires extensive multidisciplinary approaches to ensure wound protection, management of excess wound exudates and promoting healing. Developing wound healing patches that can act as a protective barrier and support healing is highly needed to manage chronic dia...

Parallel plate flow chambers are widely used to expose cultured cells to physiological flows for the investigation of a variety of diseases. These applications usually involve the generation of continuous and steady fluid flow over cell monolayers for extended durations, usually a few days. Another technique is to generate a fast high-stress wave o...

Recently, nanomedicines have gained a great deal of attention in diverse biomedical applications, including anti-cancer therapy. Being different from normal tissue, the biophysical microenvironment of tumor cells and cancer cell mechanics should be considered for the development of nanostructures as anti-cancer agents. Throughout the last decades,...

Aim Cisplatin is a standard treatment approach against lung adenocarcinoma. Resistance to cisplatin and the toxic side effects of cisplatin continue to remain a challenge. Combining drugs with different mechanisms is being investigated as a means to overcome these challenges. In ovarian cancer cells, the knockdown of RSK2 increased the sensitivity...

Background In the last few decades, zebrafish (Danio rerio) were introduced as a model organism to investigate human diseases including cardiovascular and neuronal disorders. In most zebrafish investigations, cardiac function and blood flow hemodynamics need to be assessed to study the effects of the interference on the cardiovascular system. For h...

Myosin-binding protein C 3 (MYBPC3) variants are the most common cause of hypertrophic cardiomyopathy (HCM). HCM is a complex cardiac disorder due to its significant genetic and clinical heterogeneity. MYBPC3 variants genotype-phenotype associations remain poorly understood. We investigated the impact of two novel human MYBPC3 splice-site variants:...

Cardiovascular diseases are very common nowadays as the stressful lifestyle and living conditions donate a huge part towards it. Detecting heart failures and coronary artery blockages are done through pulse oximeter, ultrasonic sound system, MRI scanning, etc. Many sensors are used to figure out the heart diseases and this proposal will bring about...

A zebrafish conference/workshop was held in Qatar between April 13 and 17, 2019. The aim of the event was to promote zebrafish research in Qatar and in Middle East/Asia by bringing together local zebrafish researchers with international colleagues. Another aim was to give basic zebrafish training to interested researchers enabling them to initiate...

In this study, a set of polylactic acid (PLA)/polyphenol extracted from date palm fruit (DP) blends were prepared by electrospinning process to be used as cell culture scaffolds for tissue engineering applications. For this purpose, PLA/DP blends with variable composition were dissolved in dichloromethane/dimethylformamide (70:30, v/v) mixture and...

Cancer metastasis is the leading cause of cancer-related mortality worldwide. To date, several in vitro methodologies have been developed to understand the mechanisms of cancer metastasis and to screen various therapeutic agents against it. Nevertheless, mimicking an in vivo microenvironment in vitro is not possible; while in vivo experiments are c...

Ultrasonography is the most widely used imaging technique in cardiovascular medicine. In this technique, a piezoelectric crystal produces, sends, and receives high frequency ultrasound waves to the body to create an image of internal organs. It enables practical real time visualization in a non-invasive manner, making the modality especially useful...

Several congenital and acquired conditions may result in severe narrowing of the urethra in men, which represent an ongoing surgical challenge and a significant burden on both health and quality of life. In the field of urethral reconstruction, tissue engineering has emerged as a promising alternative to overcome some of the limitations associated...

Fluorescent microscopy of hindbrain capillaries in a zebrafish embryo raised at 34.5°C.

Over the last decade, the zebrafish ( Danio rerio ) has emerged as a model organism for cardiovascular research. Zebrafish have several advantages over mammalian models. For instance, the experimental cost of using zebrafish is comparatively low; the embryos are transparent, develop externally, and have high fecundity making them suitable for large...

Objective. Endothelial cells (ECs) sense and respond to flow-induced mechanical stress, in part, via microtubule-based projections called primary cilia. However, many critical steps during vascular morphogenesis occur independent of flow. The involvement of cilia in regulating these stages of cranial vascular morphogenesis is poorly understood beca...

Cardiac remodeling, characterized by excessive extracellular matrix (ECM) remodeling, predisposes the heart to failure if left unresolved. Understanding the signaling mechanisms involved in excessive extracellular matrix (ECM) remodeling is necessary to identify the means to regress the development of cardiac remodeling and heart failure. Recently,...

Investigations of teratogenic effects of drugs generally involve testing the drug on animals and zebrafish embryo is a commonly used animal model for that purpose. In these studies, cardiovascular function of the animals needs to be evaluated to reveal the influence of exposure on the development of the cardiovascular system as well as on the growt...

Heart valve diseases are among the leading causes of cardiac failure around the globe. Nearly 90,000 heart valve replacements occur in the USA annually. Currently, available options for heart valve replacement include bioprosthetic and mechanical valves, both of which have severe limitations. Bioprosthetic valves can last for only 10-20 years while...

Oral cancer is a common malignancy in both men and women worldwide; this cancer is characterized by a marked propensity for invasion and spreading to local lymph nodes. On the other hand, Elaeagnus angustifolia (EA) is a medicinal plant that has been used for centuries for treating many human diseases in the Middle East. However, the effect of EA p...

The aortic valve is located at left ventricular outlet and is exposed to the highest pressure in the cardiovascular system. Problems associated with the valve leaflet movement can cause complications for the heart. Specifically, aortic stenosis (AS) arises when aortic leaflets do not efficiently open. In the present study, Lagrangian Coherent Struc...

Acute respiratory distress syndrome (ARDS) is a clinical condition that causes a disturbance in gas exchange sites inside the airways and alveoli. The Incidence rate of ARDS is about 0.1% with high mortality rate of approximation of 40% Due to inflammation, edema fluid accumulation occurs inside the lung. Patients with ARDS are unable to inflate th...

Aortic valve diseases are among the most common cardiovascular defects. Since a non-functioning valve results in disturbed blood flow conditions, the diagnosis of such defects is based on identification of stenosis via echocardiography. Calculation of disease parameters such as valve orifice area or transvalvular pressure gradient using echocardiog...

Background Today, the cell phone is the most widespread technology globally. However, the outcome of cell‐phone radiofrequency on head and neck cancer progression has not yet been explored. Methods The chorioallantoic membrane (CAM) and human head and neck cancer cell lines, FaDu and SCC25, were used to explore the outcome of cell‐phone radiofrequ...

Background: Water-pipe smoking (WPS) is the most widespread tobacco use in the Middle-East, and is rapidly spreading globally. Smoke from WP contains most of the compounds present in cigarette smoke, although in different proportions. WPS is associated with the risk of several human diseases; however, its impact on the early stage of normal develo...

Hypertrophic cardiomyopathy (HCM) is a serious heart disease and is defined as abnormal left ventricular (LV) wall thickening with diastolic dysfunction. HCM is an autosomal dominant monogenic disease caused by a mutation in 1 of 13 or more genes encoding protein components of sarcomere (i.e. sarcomere is the subunit for muscle tissue). The myosin...

During valvulogenesis, globular endocardial cushions elongate and remodel into highly organized thin fibrous leaflets. Proper regulation of this dynamic process is essential to maintain unidirectional blood flow as the embryonic heart matures. In this study, we tested how mechanosensitive small GTPases, RhoA and Rac1, coordinate atrioventricular va...

The majority of severe clinically significant forms of congenital heart disease (CHD) are associated with great artery lesions, including hypoplastic, double, right or interrupted aortic arch morphologies. While fetal and neonatal interventions are advancing, their potential ability to restore cardiac function, optimal timing, location, and intensi...

In this study influence of leaflet calcification on Aortic Valve was studied using fluid solid interactions approach. The leaflets of the aortic valve were modeled as flexible structure. The interaction between flexible leaflets and blood flow was modeled with an iterative implicit method. The time averaged wall shear stress and pressure drop param...

During cardiogenesis, congenital heart defects (CHDs), generally start as local tissue abnormalities without underlying genetic causes, suggesting abnormal hemodynamics may be an important source. Due to the scarcity of experimental techniques that permits the formation of minimally-invasive and well-controlled cardiac perturbations, experimental i...

Mechanical forces are essential contributors to and unavoidable components of cardiac formation, both inducing and orchestrating local and global molecular and cellular changes. Experimental animal studies have contributed substantially to understanding the mechanobiology of heart development. More recent integration of high-resolution imaging moda...

Bu çalışmada, aort kapakçıklarında kireçlenme sonucu kapakçık orifisinin daralması olarak tanımlanan stenoz kusurunun teşhisinde önemli, aortik kapakçık boyuncaki kan akışı ile ilgili bazı parametrelerin hesaplamalı akışkanlar modelleri yaklaşımıyla hassas şekilde hesaplanmasına yarayacak teknikler geliştirilmiştir. Geliştirilen modelde, sıvı-yapı...

Hemodynamic forces play an essential role in driving the morphogenesis of the embryonic heart and its valves. We previously found that genes that regulate heart morphogenesis like BMP2 and VEGFA, have hemodynamically specific patternings. However, how mechanical signals like wall shear stress (WSS) affect these expression levels to regulate heart m...