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    An alternative mechanism for the formation of high density lipoprotein in peripheral tissue

    , Article Scientia Iranica ; Volume 23, Issue 2 , 2016 , Pages 600-608 ; 10263098 (ISSN) Damirchi, B ; Saidi, M. S ; Rismanian, M ; Firoozabadi, B ; Amininasab, M ; Sharif University of Technology
    Sharif University of Technology  2016
    Abstract
    High Density Lipoprotein (HDL) is a lipid-protein complex responsible for transporting cholesterol and triglyceride molecules, as these compounds are unable to dissolve in aqueous environments such as a bloodstream. Among the most well-known possible structures, the belt-like structure is the most common shape proposed for this vital bimolecular complex. In this structure, the protein scaffold encompasses the lipid bilayer and a planar circular structure is formed. Several HDL simulations with embedded components in the lipid section were performed. Here, we applied a series of molecular dynamic simulations using the MARTINI coarse grain force field to investigate an HDL model, with pores of... 

    Modeling and stability analysis of truncated high density lipoprotein (HDL) system using MARTINI coarse grain technique

    , Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) ; Volume 3 A , November , 2013 ; 9780791856215 (ISBN) Damirchi, B ; Rouhollahi, A ; Sohrabi, S ; Mehr, S. M. N ; Sharif University of Technology
    American Society of Mechanical Engineers (ASME)  2013
    Abstract
    Lipoproteins are biochemical compounds containing both proteins and lipids. These particles carry chemicals like cholesterol and triglycerides that are not soluble in aqueous solutions. This paper presents modeling of lipoprotein system using coarse grain molecular dynamics technique and stability analysis of this system in a water solution like blood. A high density lipoprotein (HDL) that consists of two annular monomers is modeled. Also there are lipid bilayers located in center of the rings, so the whole HDL and lipid bilayers are called lipoprotein system. First, all atom model is provided and then coarse-grain model is obtained using MARTINI technique. Modeling of the system in all atom... 

    Simulation of low density lipoprotein (LDL) permeation into multilayer coronary arterial wall: interactive effects of wall shear stress and fluid-structure interaction in hypertension

    , Article Journal of Biomechanics ; 2017 ; 00219290 (ISSN) Roustaei, M ; Nikmaneshi, M. R ; Firoozabadi, B ; Sharif University of Technology
    Abstract
    Due to increased atherosclerosis-caused mortality, identification of its genesis and development is of great importance. Although, key factors of the origin of the disease is still unknown, it is widely believed that cholesterol particle penetration and accumulation in arterial wall is mainly responsible for further wall thickening and decreased rate of blood flow during a gradual progression. To date, various effective components are recognized whose simultaneous consideration would lead to a more accurate approximation of Low Density Lipoprotein (LDL) distribution within the wall. In this research, a multilayer Fluid-Structure Interaction (FSI) model is studied to simulate the penetration... 

    A fuzzy expert system for prescribing atorvastatin optimum dose

    , Article Koomesh ; Volume 13, Issue 1 , 2011 , Pages 43-50 ; 16087046 (ISSN) DoostHoseini, E ; Hassanpour Ezatti, M ; Navidi, H ; Abachi, T ; Sharif University of Technology
    2011
    Abstract
    Introduction: Today, Fuzzy expert systems have helped physicians in cases of uncertainty in medical decision making for prescribing drugs. Narrowing of coronary heart and reduction in heart blood flow are important causes of coronary heart disease (CHD). Control of blood lipid level is a routine treatment in CHD patients. But damage to liver is a common side effect of lipid lowering drug medication. Measurement of plasma Alanine aminotransferase level is considered as a marker of liver damage. The aim of this study was to determination of optimal dose of atorvastatin using Fuzzy expert system. Materials and Methods: in this study, Fuzzy expert system based on drug dose determination was... 

    Simulation of low density lipoprotein (LDL) permeation into multilayer coronary arterial wall: interactive effects of wall shear stress and fluid-structure interaction in hypertension

    , Article Journal of Biomechanics ; Volume 67 , 2018 , Pages 114-122 ; 00219290 (ISSN) Roustaei, M ; Nikmaneshi, M. R ; Firoozabadi, B ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    Due to increased atherosclerosis-caused mortality, identification of its genesis and development is of great importance. Although, key factors of the origin of the disease is still unknown, it is widely believed that cholesterol particle penetration and accumulation in arterial wall is mainly responsible for further wall thickening and decreased rate of blood flow during a gradual progression. To date, various effective components are recognized whose simultaneous consideration would lead to a more accurate approximation of Low Density Lipoprotein (LDL) distribution within the wall. In this research, a multilayer Fluid-Structure Interaction (FSI) model is studied to simulate the penetration... 

    Modeling of Deposition of Low Density Lipoprotein (LDL) in Carotid Artery

    , M.Sc. Thesis Sharif University of Technology Mirbagheri, Amir (Author) ; Saeedi, Mohammad Saeed (Supervisor)
    Abstract
    Atherosclerosis is one of the most important and common causes of death in the world. Atherosclerosis typically affects medium and large arteries in the body and it leads to plaque formation in arterial wall. The first stage of plaque formation has been related to accumulation of low density lipoproteins in arterial wall.
    The purpose of this research is presenting a four-layer model to describe the LDL transport in the arterial wall. The endothelium, intima, internal elastic lamina (IEL) and media are all treated as macroscopically homogeneous porous media and the volume-averaged porous media equations are employed to model various layers. The physiological parameters within the various... 

    Modeling of Blood Flow and Deposition of Low Density Lipoprotein (LDL) in Coronary Arteries

    , M.Sc. Thesis Sharif University of Technology Emami Meybodi, Ali (Author) ; Firoozabadi, Bahar (Supervisor) ; Saidi, Mohammad Said (Co-Advisor)
    Abstract
    In this thesis, hemodynamic parameters of flow and deposition of low density lipoproteins (LDL) on wall of coronary arteries with taking into account their curvature on the heart are studied. At first, numerical solution of the blood flow by assumption of blood as incompressible and Newtonian fluid for steady and pulsatile inlet is done. Then by assuming LDL particles as dilute solute in the blood, LDL transport from artery lumen into arterial wall is studied. LDL accumulation and penetration into the vessel wall cause thickening of the walls and eventually eclipse it and its known as the first stage of atherosclerosis disease. The results show that low shear region occurs on inner wall... 

    The Effect of Heart Dynamic Motion on LDL Concentration in Coronary Arteries

    , M.Sc. Thesis Sharif University of Technology Seyed Hossein, Saeed (Author) ; Dehghan Firoozabadi, Bahar (Supervisor)
    Abstract
    Heart attack is considered as one of the most common reasons of morality all over the world. Coronary Atherosclerosis is known as the major causes of heart attack. The commence and proceed of this disease is related to cross of Low Density Lipoprotein. In this project, based on numerical simulation using ANSYS Fluent, hemodynamic variables and the rate of LDL particles penetration to porous wall of coronary artery is investgated. The geometry is the first bifurcation of Left Anterior Descending and is located on the supposed sphere that represents heart configuration. Sinsuidal variations of shere radii, simulates pulsating movement of heart. Heart diameter is supposed to remain constant... 

    Coarse Grain Molecular Dynamics Simulation of Drug Carrier Translocation into Cell Membrane

    , M.Sc. Thesis Sharif University of Technology Damirchi, Behzad (Author) ; Saidi, Mohammad Said (Supervisor) ; Firoozabadi, Bahar (Supervisor)
    Abstract
    With the increasing development of the pharmaceutical industry and producing drugs with specific performance, its transfer into cells is also very important. Cell membranes are effectively impermeable to hydrophilic compounds unless the permeation is facilitated by dedicated transport systems. This means that many hydrophilic compounds, including many promising drug candidates, fail to reach their intracellular target because they cannot spontaneously cross lipid membranes. As a consequence, there is much interest in finding ways to facilitate the transport of molecules across cell membranes. Cell-penetrating peptides (CPPs) in particular have shown much promise as potential delivery agents... 

    Simulation of LDL Permeation into Multilayer Coronary Arterial Wall: Interactive Effects of Wall Shear Stress and Fluid-Structure Interaction in Hypertension

    , M.Sc. Thesis Sharif University of Technology Roustaei, Mehrdad (Author) ; Dehghan Firoozabadi, Bahar (Supervisor)
    Abstract
    Due to increased atherosclerosis-caused mortality, identification of its genesis and development is of great importance. Although, key factors of the origin of the disease is still unknown, it is widely believed that cholesterol particle penetration and accumulation in arterial wall is mainly responsible for further wall thickening and decreased rate of blood flow during a gradual progression. To date, various effective components are recognized whose simultaneous consideration would lead to a more accurate approximation of Low Density Lipoprotein (LDL) distribution within the wall. In this research, a multilayer Fluid-Structure Interaction (FSI) model is studied to simulate the penetration... 

    Simulation of the Influence of Hypertension on Low Density Lipoprotein (Ldl) Permeation into Multilayer Coronary Bifurcation

    , M.Sc. Thesis Sharif University of Technology Moniri Piri, Mohammad (Author) ; Firoozabadi, Bahar (Supervisor)
    Abstract
    Atherosclerosis, due to the penetration of low-density lipoprotein particles (LDL) into the arterial wall, is one of the most common and death-leading diseases in today's world. Due to its importance, extensive research has been conducted on the factors that affect this disease. In this thesis, a numerical study of the effects of Wall Shear Stress (WSS), non-Newtonian behavior of blood, different hematocrit values, and blood pressure on LDL permeation through the artery wall layers are investigated in a 4-layer wall model of a coronary bifurcation. To obtain the velocity and concentration fields in the domain, momentum, Brinkman, and mass transport equations are solved in the lumen and wall... 

    Numerical Investigation of Hypertension in Plaque Formation and Growth in Human Aorta

    , M.Sc. Thesis Sharif University of Technology Benvidi, Amir Abbas (Author) ; Firoozabadi, Bahar (Supervisor)
    Abstract
    Nowadays, cardiovascular diseases are among the most prevalent cause of death worldwide. Besides, atherosclerosis is a cardiovascular disease happening with the continuous narrowing of vessels, especially medium and large-sized arteries. Moreover, the human aorta is vulnerable to this phenomenon. Atherosclerosis happens when the excess LDL in the blood flow penetrates the arterial wall. Then, the LDL is oxidized, thereby recruiting monocytes as the response against oxidized LDL. After monocytes enter the arterial wall, they differentiate and become macrophages. Macrophages then transform into foam cells by ingesting the oxidized LDL. The fatty foam cells are eventually responsible for the... 

    A simple model of intimal thickening-effects of hypertension

    , Article 2012 19th Iranian Conference of Biomedical Engineering, ICBME 2012 ; 2012 , Pages 276-281 ; 9781467331302 (ISBN) Mirbagheri, S. A ; Saidi, M. S ; Firoozabadi, D ; Sharif University of Technology
    2012
    Abstract
    A vast amount of death in the world has been attributed to atherosclerosis. This disease causes plaque formation and finally lack of blood supply to an organ. The prominent aim of this study is proposing an accurate and simple model to investigate the process of arterial wall thickening. In order to investigate LDL (low density lipoprotein) accumulation in arterial wall which is considered the first stage of atherosclerosis, a four layer model for arterial wall consisting of endothelium, intima, IEL and media is presented. All layers are treated as homogenous porous media. The four-layer arterial wall model is the most powerful and reliable tool for modeling LDL transport within arterial... 

    Effects of hypertension on Intima-Media Thickness (IMT); application to a human carotid artery

    , Article Scientia Iranica ; Volume 23, Issue 4 , 2016 , Pages 1731-1740 ; 10263098 (ISSN) Mirbagheri, S. A ; Saidi, M. S ; Sohrabi, S ; Firoozabadi, B ; Banazadeh, M. H ; Sharif University of Technology
    Sharif University of Technology 
    Abstract
    A vast number of deaths in the world have been attributed to atherosclerosis. The prominent aim of this study is proposing an accurate and simple model to investigate the process of arterial wall thickening. In order to investigate LDL (Low Density Lipoprotein) accumulation in arterial wall, a four layer model for arterial wall consisting of endothelium, intima, IEL, and media is presented. All layers are treated as homogenous porous media. This model has been solved both numerically and analytically. Obtained accumulated LDL in the intima is used to calculate oxidized LDL flux. Also, the presented model and clinical data are used to prepare the growth model for arterial wall. Furthermore,... 

    Association of glomerular and tubular dysfunction with glycaemic control, lipid, lipoprotein, apolipoprotein and antioxidant status in type 2 diabetes mellitus

    , Article Singapore Medical Journal ; Volume 48, Issue 9 , 2007 , Pages 840-846 ; 00375675 (ISSN) Farvid, M. S ; Djalali, M ; Siassi, F ; Farvid, S. S ; Sharif University of Technology
    Singapore Medical Association  2007
    Abstract
    Introduction: This study was conducted to investigate the relationship of glomerular and tubular dysfunctions with glycaemic control, lipid, lipoprotein, apolipoproteins and antioxidant status in 72 patients with type 2 diabetes mellitus. Methods: Urine albumin concentration was measured by immunoturbidimetric and urine N-acetyl-beta-D-glucosaminidase (NAG) and alanine aminopeptidase (AAP) activities with colorimetric methods. Glycated haemoglobin was measured using affinity chromatography. Erythrocyte glu ta thione reductase and glutathione peroxidase activities and serum levels of malondialdehyde, lipids, lipoproteins and apolipoproteins were determined in patients with type 2 diabetes... 

    Effects of Heart Dynamic Motion on Blood Hemodynamics and LDL Accumulation in Coronary Bifurcation

    , M.Sc. Thesis Sharif University of Technology Olyaei, Mostafa (Author) ; Firoozabadi, Bahar (Supervisor)
    Abstract
    In this thesis, the effect of heart dynamic motion and pulsatile inflow on blood hemodynamics and LDL permeation into the arterial wall in a 3-D coronary artery bifurcation was investigated. To determine the effect of each factor alone and simultaneous effect of both factors i.e. heart dynamic motion and pulsatile inflow, flow simulations were performed in four cases i.e. steady-static, steady-dynamic, pulsatile-static, and pulsatile-dynamic. The results of flow simulations showed that dynamic geometry and pulsatile inflow have considerable impact on temporal variations of wall shear stress (WSS), even though the effect of pulsatile inflow on WSS variation dominates over the effect of... 

    The metabolome profiling of obese and non-obese individuals: Metabolically healthy obese and unhealthy non-obese paradox

    , Article Iranian Journal of Basic Medical Sciences ; Volume 23, Issue 2 , 2020 , Pages 186-194 Chashmniam, S ; Madani, N. H ; Ghoochani, B. F. N. M ; Safari Alighiarloo, N ; Khamseh, M. E ; Sharif University of Technology
    Mashhad University of Medical Sciences  2020
    Abstract
    Objective(s): The molecular basis of “metabolically healthy obese” and “metabolically unhealthy non-obese” phenotypes is not fully understood. Our objective was to identify metabolite patterns differing in obese (metabolically healthy vs unhealthy (MHO vs MUHO)) and non-obese (metabolically healthy vs unhealthy (MHNO vs MUHNO)) individuals. Materials and Methods: This case-control study was performed on 86 subjects stratified into four groups using anthropometric and clinical measurements: MHO (21), MUHO (21), MHNO (22), and MUHNO (22). Serum metabolites were profiled using nuclear magnetic resonance (NMR). Multivariate analysis was applied to uncover discriminant metabolites, and enrichment... 

    NMR spectroscopy-based metabolomic study of serum in sulfur mustard exposed patients with lung disease

    , Article Biomarkers ; Volume 22, Issue 5 , 2017 , Pages 413-419 ; 1354750X (ISSN) Nobakht, B.F., M. Gh ; Arefi Oskouie, A ; Rezaei Tavirani, M ; Aliannejad, R ; Taheri, S ; Fathi, F ; Naseri, M. T ; Sharif University of Technology
    Taylor and Francis Ltd  2017
    Abstract
    Sulfur mustard (SM) is a vesication chemical warfare agent for which there is currently no antidote. Despite years of research, there is no common consensus about the pathophysiological basis of chronic pulmonary disease caused by this chemical warfare agent. In this study, we combined chemometric techniques with nuclear magnetic resonance (NMR) spectroscopy to explore the metabolic profile of sera from SM-exposed patients. A total of 29 serum samples obtained from 17 SM-injured patients, and 12 healthy controls were analyzed by Random Forest. Increased concentrations of seven amino acids, glycerol, dimethylamine, ketone bodies, lactate, acetate, citrulline and creatine together with the... 

    Metabolomics diagnostic approach to mustard airway diseases: A preliminary study

    , Article Iranian Journal of Basic Medical Sciences ; Volume 21, Issue 1 , 2018 , Pages 59-69 ; 20083866 (ISSN) Nobakht Mothlagh Ghoochani, B. F ; Aliannejad, R ; Oskouie, A. A ; Tavirani, M. R ; Kalantari, S ; Naseri, M. T ; Baghban, A. A ; Parastar, H ; Aliakbarzadeh, G ; Sharif University of Technology
    Mashhad University of Medical Sciences  2018
    Abstract
    Objective(s): This study aims to evaluate combined proton nuclear magnetic resonance (1H NMR) spectroscopy and gas chromatography-mass spectrometry (GC-MS) metabolic profiling approaches, for discriminating between mustard airway diseases (MADs) and healthy controls and for providing biochemical information on this disease. Materials and Methods: In the present study, analysis of serum samples collected from 17 MAD subjects and 12 healthy controls was performed using NMR. Of these subjects, 14 (8 patients and 6 controls) were analyzed by GC-MS. Then, their spectral profiles were subjected to principal component analysis (PCA) and orthogonal partial least squares regression discriminant...