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    A Library For Developing Optimization Algorithms In Metabolic Network Analysis

    , M.Sc. Thesis Sharif University of Technology Ghadimi Deylami, Iman (Author) ; Tefagh, Mojtaba (Supervisor)
    In systems biology, one of the most important biological systems that is analyzed and investigated is the metabolic network. A metabolic network is a complete set of metabolic and physical processes that determine the physiological and biochemical characteristics of a cell. These networks encompass metabolic chemical reactions, metabolic pathways, and regulatory interactions that govern these reactions. Therefore, metabolic networks at the genome scale are immensely large, making even efficient algorithms time-consuming for their analysis. To address this issue, reducing metabolic networks is crucial, as it significantly decreases the execution time of algorithms and enhances computational... 

    Metabolic Engineering of Yeast Saccharomyces Cerevisiae for Production of Fatty Acids and Its Derivatives

    , M.Sc. Thesis Sharif University of Technology Homayoonfar, Mohammad (Author) ; Roosta Azad, Reza (Supervisor) ; Sardari, Soroush (Supervisor)
    With the increasing emphasis on production of various chemicals by biotechnology industry, the establishment of optimal cell factories for the maximum production of a specific chemical product will be a serious challenge in large-scale production in this industry. Metabolic engineering is a branch of biochemical engineering that has been developed to achieve this and the approaches in it seek to address this challenge. In this study, focusing on increasing production of fatty acids by yeast cells of Saccharomyces cerevisiae, and using a combination of computational and laboratory methods to present a methodology for the optimal design of culture media. Thus, using the constraint-based... 

    Modeling the Endothelial Function in the Brachial Artery Using Photoplethysmography

    , M.Sc. Thesis Sharif University of Technology Mashayekhi, Ghoncheh (Author) ; Zahedi, Edmond (Supervisor) ; Jahed, Mehran (Supervisor)
    Flow Mediated Dilation (FMD) is a non-invasive method for endothelial function assessment providing an index extracted from ultrasonic B-mode images. Although utilized in the research community, the difficulty of its application and high cost of ultrasonic device prevent it from being widely used in clinical settings. In this study we show that substituting the ultrasonic device with more easily handled and low cost photoplethysmography and electrocardiography is possible. We introduce new indices based on the photoplethysmogram (PPG) and electrocardiogram (ECG) and show that they are correlated with the ultrasound-based FMD index. To this end, conventional ultrasound FMD test was carried... 

    Hyperbolic and Metabolic Forms and Involutions

    , Ph.D. Dissertation Sharif University of Technology Nokhodkar Hassan Abadi, Amir Hossein (Author) ; Gholamzadeh Mahmoudi, Mohammad (Supervisor) ; Mahdavi-Hezavehi, Mohammad (Supervisor)
    In this thesis, we investigate the involutions of a Clifford algebra induced by involutions of orthogonal group in characteristic two. Several properties of these involutions, such as the relations between their invariants and their decompositions are studied. Also it is shown that a tensor product of quaternion algebras with involution can be expressed as the Clifford algebra of a suitable quadratic form with an involution induced by an involution of orthogonal group. Finally, in connection with the Pfister factor conjecture formulated by D. B. Shapiro, split tensor products of quaternion algebras with involution over a field of characteristic two are investigated  

    Numerical Simulation of Glucose Metabolism and Hepatocyte Viability within a Microfluidic

    , M.Sc. Thesis Sharif University of Technology Nejadnasrollah, Farzam (Author) ; Firoozabadi, Bahar (Supervisor)
    The advent of microfluidics as suitable environments for culturing cells is associated with some challenges such as shear stresses applied on the cells. In fact, hepatocytes lose their function as exposed to high shear stresses similar to other cell types. Moreover, among all factors needed for cell viability, feeding hepatocytes with adequate oxygen is of great importance due to their high demand for oxygen compared the other cells. In this thesis, different types of cultures including 2D and 3D has been used in order that shear stresses would be in allowed range and provision of hepatocytes with sufficient oxygen concentrations has been ensured as well. In addition to supplying hepatocytes... 

    Dynamic Simulation and Control of Reactive Systems Involving Metabolic Pathways

    , M.Sc. Thesis Sharif University of Technology Aghaee Foroushani, Mohammad (Author) ; Bozorgmehry Bozarjomehry, Ramin (Supervisor) ; Setoodeh, Payam (Co-Supervisor)
    In this project, modeling, simulation, and control of the Saccharomyces Cerevisiae were studied. In the first section, simulation and control of a structural model of saccharomyces Cerevisiae were performed. Fuzzy Logic Controller (FLC) as a model-independent controller and Global Linearization Controller (GLC) as a model-based controller were designed. Additionally, two types of Kalman filters were designed to predict all states of the structural model: 1-Extended Kalman Filter (EKF), 2- Unscented Kalman Filter (UKF). As a concise explanation, the control action of the GLC is a function of all states of the model, and since that measuring all metabolites is not practical, the EKF and UKF... 

    Simulation of Optimum Nutrition in Bioreactors

    , M.Sc. Thesis Sharif University of Technology Radfar, Marjan (Author) ; Abdekhodaie, Mohammad Jafar (Supervisor) ; Mehrvar, Mehrab (Supervisor)
    In this study, a semi-structured model for the growth and production of lactase in an aerated bioreactor by Kluyveromyces marxianus, growing on cheese whey, was developed. Three modes of culture, consisting of batch, fed-batch and a controlled-release system were investigated. Modeling was based on three metabolic pathways, representing the growth of Kluyveromyces marxianus. Lactose and oxygen consumption, cell growth, and also lactase and ethanol production rates were determined in the model. Induction was considered as the governing mechanism for enzyme production. The model showed good agreement with the experimental data in batch and fed-batch cultures. Controlled-release system is a... 

    Ontological Study of Metabolic Networks to Develop an Identification Software for Metabolic Networks

    , M.Sc. Thesis Sharif University of Technology Mohammadi Peyhani, Homa (Author) ; Bozorgmehry Boozarjomehry, Ramin (Supervisor)
    Simulation of biological behaviors as the pre requirement for control and optimization, especially for recognition and treating diseases, requires studying involved reactions which may or may not be accessible. In the other side, finding the correct network structures and related mathematical expressions to simulate biological behaviors is a complicated problem due to multi aspect interactions among biological reactions, which imply an approach that integrate the knowledge coming from multiple discipline including biological concepts, mathematical modelling, bioinformatics and advanced programming. In this study we aim to analyze this problem using ontological inference to develop a... 

    Investigation of Anticancer Drug Metabolism in Saccharomyces Cerevisiae as a Drug Resistance Model

    , M.Sc. Thesis Sharif University of Technology Hamed Rahimi, Reza (Author) ; Yaghmaei, Soheila (Supervisor) ; Sardari, Soroush (Supervisor)
    Cancer is a life-threatening group of diseases that arises from the uncontrolled growth and division of cells in the body. Treatment options for cancer include surgery, chemotherapy, radiation therapy, immunotherapy, targeted therapy, and hormone therapy. However, resistance to anticancer drugs can develop through a variety of mechanisms, such as the upregulation of drug efflux pumps and alterations in DNA repair mechanisms. One common mechanism of drug resistance is through changes in metabolism, where cancer cells switch to alternative metabolic pathways to survive and evade the effects of anticancer drugs. The development of new drugs targeting specific molecules and pathways involved in... 

    Context-Specific Reconstruction and Gap-Filling of Metabolic Networks by Sparse Reconciliation of Data Inconsistencies

    , M.Sc. Thesis Sharif University of Technology Fathi, Ali (Author) ; Tefagh, Mojtaba (Supervisor)
    With the increasingly collected biological data, appropriate usage of this data is of great importance for understanding and predicting biological systems and has been the aim of experiments and data collections. A famous category of biological data is known as “omics” which refers to transcriptomics, proteomics, metabolomics, and fluxomics, from different cells or tissues in various media and conditions. This set of data is regularly used for tasks such as studying cells and organisms, understanding cell states, cancer prediction, etc. and is of great importance in Systems Biology.In this thesis, we concentrate on studying cells or organisms using such data, where during that process, we... 

    You are what you eat: Sequence analysis reveals how plant microRNAs may regulate the human genome

    , Article Computers in Biology and Medicine ; Volume 106 , 2019 , Pages 106-113 ; 00104825 (ISSN) Kashani, B ; Hasani Bidgoli, M ; Motahari, S. A ; Sedaghat, N ; Modarressi, M. H ; Sharif University of Technology
    Elsevier Ltd  2019
    Background: Nutrigenomic has revolutionized our understanding of nutrition. As plants make up a noticeable part of our diet, in the present study we chose microRNAs of edible plants and investigated if they can perfectly match human genes, indicating potential regulatory functionalities. Methods: miRNAs were obtained using the PNRD database. Edible plants were separated and microRNAs in common in at least four of them entered our analysis. Using vmatchPattern, these 64 miRNAs went through four steps of refinement to improve target prediction: Alignment with the whole genome (2581 results), filtered for those in gene regions (1371 results), filtered for exon regions (66 results) and finally... 

    Use of the freely-swimming, Serratia marcescens bacteria to enhance mixing in microfluidic systems

    , Article ASME 2009 International Mechanical Engineering Congress and Exposition, 13 November 2009 through 19 November 2009 ; Volume 12, Issue PART A , 2010 , Pages 463-467 ; 9780791843857 (ISBN) Peysepar, M ; Shafii, M. B ; Rasoulian, R ; Jamalifar, H ; Fazeli, M. R ; Sharif University of Technology
    American Society of Mechanical Engineers (ASME) 
    Mixing has become a challenge in micro-fluidic systems because of the low Reynolds number in micro-channels. The method which is implemented in this paper is to use freely-swimming bacteria to enhance the mixing process. Accordingly, the Serratia marcescens bacteria were used for this matter. The mixing performance of the system is quantified by measuring the diffusion rate of Rhodamine B in a particular section of a channel connected to a chamber with varying Rhodamine B concentration. The concentration of Rhodamine B was measured using the Laser Induced Fluorescence (LIF) technique. The channel is in the form of a pipe and is closed on the extending side. In this paper, it is demonstrated... 

    Urine concentrating mechanism modelling in rat kidney inner medulla

    , Article 2016 23rd Iranian Conference on Biomedical Engineering and 2016 1st International Iranian Conference on Biomedical Engineering, ICBME 2016, 23 November 2016 through 25 November 2016 ; 2017 , Pages 111-116 ; 9781509034529 (ISBN) Sanatkhani, S ; Saidi, M. S ; Banazadeh, M. H ; Sharif University of Technology
    Physicians use charts that are prepared by experiments on animals or humans to prescribe drug dosage for patients. This method requires some precious amount of time by the Ministry of Health to approve new drugs to be used in healthcare centers. Three-dimensional modeling of the inner medulla by considering the known physiological features help us to predict the distribution of a drug or any minerals in the kidney. In this study we present modeling of the important species distribution including Na+ and urea in the rat inner medulla that influence the urine concentrating mechanism. We use a C++ code to develop the inner medulla geometry based on physiological data to better capture the... 

    Untargeted metabolomics based on nuclear magnetic resonance spectroscopy and multivariate classification techniques for identifying metabolites associated with breast cancer patients

    , Article Chemometrics and Intelligent Laboratory Systems ; Volume 223 , 2022 ; 01697439 (ISSN) Esmaeili, P ; Khalilvand, M ; Tavakolizadeh, H ; Parastar, H ; Sharif University of Technology
    Elsevier B.V  2022
    In this study, multivariate classification techniques combined with proton nuclear magnetic resonance (1HNMR) spectroscopy is proposed to identify breast cancer biomarkers that can precisely distinguish between healthy control and breast cancer (BC) patients. In this regard, first optimizing the metabolite extraction procedure was performed using Box-Behnken design (BBD). Then, data-driven soft independent modeling of class analogy (DD-SIMCA) model and partial least squares-discriminant analysis (PLS-DA) were successfully utilized for separating healthy from BC patient's classes. On this matter, both DD-SIMCA and PLS-DA models could successfully distinguish the healthy class from the BC... 

    Two schemes for production of biosurfactant from Pseudomonas aeruginosa MR01: Applying residues from soybean oil industry and silica sol–gel immobilized cells

    , Article Colloids and Surfaces B: Biointerfaces ; Volume 152 , 2017 , Pages 159-168 ; 09277765 (ISSN) Bagheri Lotfabad, T ; Ebadipour, N ; Roostaazad, R ; Partovi, M ; Bahmaei, M ; Sharif University of Technology
    Elsevier B.V  2017
    Rhamnolipids are the most common biosurfactants and P. aeruginosa strains are the most frequently studied microorganisms for the production of rhamnolipids. Eco-friendly advantages and promising applications of rhamnolipids in various industries are the major reasons for pursuing the economic production of these biosurfactants. This study shows that cultivation of P. aeruginosa MR01 in medium contained inexpensive soybean oil refinery wastes which exhibited similar levels and homologues of rhamnolipids. Mass spectrometry indicated that the Rha-C10-C10 and Rha-Rha-C10-C10 constitute the main rhamnolipids in different cultures of MR01 including one of oil carbon source analogues. Moreover,... 

    Toxicity of graphene and graphene oxide nanowalls against bacteria

    , Article ACS Nano ; Volume 4, Issue 10 , October , 2010 , Pages 5731-5736 ; 19360851 (ISSN) Akhavan, O ; Ghaderi, E ; Sharif University of Technology
    Bacterial toxicity of graphene nanosheets in the form of graphene nanowalls deposited on stainless steel substrates was investigated for both Gram-positive and Gram-negative models of bacteria. The graphene oxide nanowalls were obtained by electrophoretic deposition of Mg2+-graphene oxide nanosheets synthesized by a chemical exfoliation method. On the basis of measuring the efflux of cytoplasmic materials of the bacteria, it was found that the cell membrane damage of the bacteria caused by direct contact of the bacteria with the extremely sharp edges of the nanowalls was the effective mechanism in the bacterial inactivation. In this regard, the Gram-negative Escherichia coli bacteria with an... 

    The use of a cis-dioxomolybdenum(VI) dinuclear complex with quadradentate 1,4-benzenediylbis(benzyldithiocarbamate)(2-) as model compound for the active site of oxo transfer molybdoenzymes: Reactivity, kinetics, and catalysis

    , Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 88 , 2012 , Pages 210-215 ; 13861425 (ISSN) Moradi Shoeili, Z ; Boghaei, D. M ; Sharif University of Technology
    Dinuclear cis-dioxomolybdenum(VI) complex [{MoO 2(Bz 2Benzenediyldtc)} 2] coordinated by a quadradentate dithiocarbamate (Bz 2Benzenediyldtc 2- = 1,4-benzenediylbis(benzyldithiocarbamate)(2-)) has been prepared and characterized by elemental analysis, 13C NMR, IR and UV-vis spectroscopy. The kinetics of the oxygen atom transfer between [{MoO 2(Bz 2Benzenediyldtc)} 2] and PPh 3 was studied spectrophotometrically in CH 2Cl 2 medium at 520 nm and four different temperatures, 288, 293, 298 and 303 K, respectively. The reaction follows second order kinetics with the rate constant k = 0.163(2) M -1 S -1 and its increasingly strong absorption at 520 nm clearly indicate the formation of a μ-oxo... 

    Thermodynamic properties of aqueous salt containing urea solutions

    , Article Fluid Phase Equilibria ; Volume 325 , July , 2012 , Pages 71-79 ; 03783812 (ISSN) Sadeghi, M ; Held, C ; Samieenasab, A ; Ghotbi, C ; Abdekhodaie, M. J ; Taghikhani, V ; Sadowski, G ; Sharif University of Technology
    Urea and inorganic ions are present in some of the physiological systems, e.g. urine. Understanding the interactions in urea/salt/water is a preliminary step to shed light on more complicated behavior of multi-component physiological systems. State-of-the-art models as well as thermophysical properties can be applied to understand the interactions in these systems. In order to determine such interactions densities, mean ionic activity coefficients (MIACs), osmotic coefficients, and solubility were measured in aqueous solutions of urea and different salts. Densities were determined at temperatures 293.15, 303.15, and 313.15K for urea concentrations up to 3molal and up to 1molal for NaCl.... 

    Theoretical modeling of actin-retrograde-flow passing clusters of confined T cell receptors

    , Article Mathematical Biosciences ; Volume 283 , 2017 , Pages 1-6 ; 00255564 (ISSN) Ghasemi V., A ; Firoozabadi, B ; Saidi, M. S ; Sharif University of Technology
    Elsevier Inc  2017
    Through the activation process of T cells, actin filaments move from the cell periphery toward the cell center. The moving filaments engage with T cell receptors and thus contribute to transportation of the signaling molecules. To study the connection between the moving actin filaments and T cell receptors, an experiment available in the literature has measured filaments flow velocity passing over a region of confined clusters of receptors. It shows that flow velocity decreases in the proximity of the receptors, and then regains its normal value after traversing the region, suggesting a dissipative friction-like connection. In this work, we develop a minimal theoretical model to re-examine... 

    The metabolomics signature associated with responsiveness to steroid therapy in focal segmental glomerulosclerosis: A pilot study

    , Article Revista de Investigacion Clinica ; Volume 71, Issue 2 , 2019 , Pages 106-115 ; 00348376 (ISSN) Chashmniam, S ; Kalantari, S ; Nafar, M ; Boroumandnia, N ; Sharif University of Technology
    Instituto Nacional de la Nutricion Salvador Zubiran  2019
    Background: Focal segmental glomerulosclerosis (FSGS) is considered one of the most severe glomerular diseases and around 80% of cases are resistant to steroid treatment. Since a large proportion of steroid-resistant (SR) FSGS patients progress to end-stage renal disease, other therapeutic strategies may benefit this population. However, identification of non-invasive biomarkers to predict this high-risk population is needed. Objective: We aimed to identify the biomarker candidates to distinguish SR from steroid-sensitive (SS) patients using metabolomics approach and to identify the possible molecular mechanism of resistance. Methods: Urine was collected from biopsy-proven FSGS patients...