Search for: extracellular-matrix
0.008 seconds
Total 44 records

    Global Classical Solutions to a Doubly Haptotactic Cross-diffusion System Modeling Oncolytic Virotherapy

    , M.Sc. Thesis Sharif University of Technology Kerachi, Yasmin (Author) ; Hesaraki, Mahmoud (Supervisor)
    This thesis studies a haptotaxis system proposed as a model for oncolytic virotherapy , accounting for interaction between uninfected cancer cells , infected cancer cells , extracellular matrix (ECM) and oncolytic virus . In addition to random movement , both uninfected and infected tumor cells migrate haptotactically toward higher ECM densities; moreover , besides degrading the non-diffusible ECM upon contact the two cancer cell populations are subject to an infection-induced transition mechanism driven by virus particles which are released by infected cancer cells ,and which assault the uninfected part of the tumor .The main results assert global classical solvability in an associated... 

    Fabrication of Vascularized Scaffold Containing Cardiac Tissue-derived Decellularized Extracellular Matrix Using Bioprinter

    , M.Sc. Thesis Sharif University of Technology Panahi Velashedi, Behnam (Author) ; Mashayekhan, Shohreh (Supervisor)
    In this study, a new bioink was introduced for the production of tubular tissue structures for cardiac tissue engineering by bioprinter using the FRESH (Freeform Reversible Embedding of Suspended Hydrogels) method. The novel bioink that we used was a combination of cardiac extracellular matrix (cECM) and oxidized alginate. The cardiac extracellular matrix was used to increase the biomimetic of the printed structures to the actual tissue of the body, and also to create sites for cell adhesion, and to improve cell growth and survival. We used alginate oxide (oxidation degree: 5%) to increase the mechanical properties of the tissue. Alginate oxidation has been due to extracellular matrix (ECM)... 

    Dosign and Construction of Natural Polymers-based Hydrogels for Cartilage Tissue Engineering

    , M.Sc. Thesis Sharif University of Technology Nasiri, Bita (Author) ; Mashayekhan, Shohreh (Supervisor) ; Hajebrahimi, Zahra (Supervisor)
    Once damaged, articular cartilage has very little capacity for spontaneous healing because of the avascular nature of the tissue. Although many repair techniques have been proposed over the past decades, none has successfully regenerated long-lasting tissue to replace damaged cartilage. Tissue engineering have recently demonstrated tremendous approaches for regeneration of cartilage tissue lesions. Tissue engineering is based on three principles: cells, scaffolds for cell adhesion and growth factors. Three-dimensional biodegradable scaffolds play an important role in tissue engineering. In this study, novel cross-linked hybrid chitosan/ECM scaffolds were prepared for articular cartilage... 

    Synthesis, Characterization and Optimization of an In situ Forming Hydrogel Derived from Extracellular Matrix for Cardiac Tissue Engineering Applications

    , M.Sc. Thesis Sharif University of Technology Mousavi, Ali (Author) ; Mashayekhan, Shohreh (Supervisor) ; Baheiraei, Nafiseh (Supervisor) ; Pourjavadi, Ali (Co-Supervisor)
    Myocardial Infarction occurs due to sudden blockage in a coronary artery and causes necrosis of myocardial tissue. Since myocardium is unable to self-regenerate, cardiac tissue engineering has become a promising therapeutic approach for MI treatment by restoring heart function via combination of cells, biomaterials and signaling factors. For this purpose, myocardial extracellular matrix (ECM) is an attractive biomaterial providing better biomimetic for cultured cells. In this project, we synthesized an in situ forming hydrogel derived from myocardial ECM and for improving mechanical and electrical properties of ECM hydrogel we added oxidized alginate (OA) with 5% oxidation degree and APTMS... 

    Design and Fabrication of Three Dimensional Scaffold Using Bio-Printing Technique for Cartilage Tissue Engineering

    , M.Sc. Thesis Sharif University of Technology Mohsenifard, Sadaf (Author) ; Mashayekhan, Shohreh (Supervisor) ; Hassanzadeh, Zabiollah (Co-Supervisor)
    Herein, we successfully prepared two types of hydrogels, alginate-beta-cyclodextrin based hydrogel and alginate without beta-cyclodextrin hydrogel in order to use in cartilage tissue engineering. At first, sodium alginate was modified with beta-cyclodextrin ring due to incorporate the kartogenin (KGN) differentiating drug in the hydrogel structure. For confirming the correctness of the modification reactions, H-NMR spectroscopy was used. In the presence of phenolized-ECM, alginic acid, modified alginate with beta cyclodextrin, HRP, H2O2, calcium carbonate, and glucono-delta-lactone (GDL), ECM-alginate-IPN and ECM-modified-alginate-IPN hydrogels were synthesized. Then, the KGN was loaded on... 

    Optimization of Cell Proliferation on Polymeric Carriers Composed of Accelular Heart Matrix

    , M.Sc. Thesis Sharif University of Technology Ghanbari Asl, Sasan (Author) ; Mashayekhan, Shohreh (Supervisor) ; Abd Khodaei, Mohammad Jafar (Supervisor)
    Following heart coronary artery occlusion, heart stroke (HS) happens which leads to the creation of a dead zone on heart tissue named Myocardial Infarction (MI), the presence of which on a patient’s heart will result in succeeding HSs and the death of the patient. In this study, porous microcarriers capable of being utilized in cardiovascular tissue engineering is fabricated using a mixture of myocardium ectracellular matrix (ECM) and Chitosan (Cs). Results of Elasticity tests, SEM images, swelling behavior, biodegradability test, and cell proliferation assay showed that the scaffold consisting of 3.5% (w/w) Chitosan and 0.66% (w/w) ECM has the best potential in providing cardiovascular... 

    Design and Optimization of Channeled Hydrogel Scaffold Based on Extracellular Matrix of Heart Tissue with Oxygen Release Capability

    , M.Sc. Thesis Sharif University of Technology Ghasemi, Sara (Author) ; Mashayekhan, Shohreh (Supervisor) ; Khorshidi, Sajedeh (Co-Supervisor)
    Despite the increase in the number of cardiovascular diseases worldwide, the number of new drugs to treat these diseases has been decreasing in the last decade. Current preclinical drug evaluation strategies, which use cell cultures and oversimplified animal models, cannot meet the growing demand for new and effective drugs. In the last decade, the development of microfluidic bioreactors and organ-on-chip systems to improve the drug screening process has been increasing significantly. These systems have shown many advantages over previous preclinical models. Despite all these advantages, keeping the oxygen concentration at the optimal physiological level in microfluidic systems has its own... 

    Processing and Investigation of the Properties of Chitosan/Celloluse Nanocomposite Wound Dressing Fabricated by Electrospinning Method

    , M.Sc. Thesis Sharif University of Technology Faraji Safiloo, Negar (Author) ; Bagheri, Reza (Supervisor)
    It is a common method to use some proper materials such as honey, herbal fibers, and minerals for covering the wounds as an effective treatment. Nowadays biopolymers and new methods of nanofiber production to build a structure similar to the natural extracellular matrix (ECM) like electrospinning are used to reduce the time of restoration and prevent from the effects of wounds such as bedsores, diabetic ulcers, and severe burns. For effective design of a wound dressing, wound feature, recovery time, physical, mechanical, and biological properties should be considered in order to best as possible heal the bound. In this research, cellulose nanocrystals with average aspect ratio of 11.8 and... 

    Kinetics of Animal Cell Adhesion Mediated by the Diffusion of Cell Wall Receptors: Effect of Mechanical Stiffness and Electrical Charges of the Substrate

    , M.Sc. Thesis Sharif University of Technology Samadi Dooki, Aref (Author) ; Mohammadi Shoja, Hossein (Supervisor)
    Viability and proliferation of cells in cell culture mainly depends on i) cell culture medium, ii) cell-cell interaction, and iii) the supporting scaffold. Among these factors, and within recent years, surface and mechanical properties of the supporting ECM has attracted many researchers. Experiment results show that the animal cell adhesion is accelerated on stiffer scaffolds. Electrical charge of the scaffold is also a determinant term in the kinetics of adhesion and on a relatively charged scaffold, one can expect an increment in kinetics of adhesion front movement. This is due to the natural negative charges of the cell wall membrane. In this thesis, an analytical model is proposed to... 

    Fabrication of in Situ Forming Hydrogels Composed of Acellular Cartilage Matrix with Improved Mechanical Properties for Recovery of Local Damages in Articular Cartilage

    , M.Sc. Thesis Sharif University of Technology Shojarazavi, Nastaran (Author) ; Mashayekhan, Shohreh (Supervisor) ; Hassanzadeh, Zabihollah (Co-Supervisor)
    Since cartilage has limited self-regeneration, in-situ forming hydrogels can act as an ideal scaffold for cartilage tissue engineering to fill the defect gap due to their ability to homogeneously encapsulate the desired cells, efficient mass transfer and minimally invasive characteristics. In this project, an injectable hydrogel with improved structure by adding silk fibroin (SF) nanofibers and better biochemical properties by employing the cartilage extracellular matrix (ECM) was fabricated. The in-situ forming hydrogel is consisted of different concentrations of ionic crosslinked alginate incorporated with different concentrations of SF nanofibers and 1% w/v enzymatically crosslinked... 

    Design and Fabrication of Scaffold Composed of Acellular Cartilage Matrix and Chitosan

    , M.Sc. Thesis Sharif University of Technology Sivandzade, Farzane (Author) ; Mashayekhan, Shohreh (Supervisor) ; Hasanzadeh, Zabihollah (Supervisor)
    Cartilage is an avascular tissue, having limited ability to repair itself. Since the methods for treatment of cartilage defects have been not effective, in recent years, new therapies based on tissue engineering are considered.This paper reports on the development of porous microcarriers composed of acellular matrix of cartilage and natural polymer chitosan. Microcarriers were prepared by electrospray method. Results of mechanical tests, SEM imaging, water uptake behaviour, biodegradation test, and MTT assay demonstrated that the microcarriers composed of 2% (wt) chitosan and 1% (wt) ECM has the best potential for growth and proliferation of primary chondrocyte cells. These results... 

    Characterization of Tissue Structure of Natural Scaffolds Made of Rat Kidney

    , M.Sc. Thesis Sharif University of Technology Rezaiepour, Yashar (Author) ; Asgari, Sirius (Supervisor) ; Kajbafzadeh, Abdolmohammad (Supervisor)
    Recently, the deficiency of methods like organ donation and medicine made tissue engineering a prospective method in regeneration of tissues. Despite all of its advantageous like any other method, it has its own weak points. Its major disadvantage is the probability of rejection by the host body. Using proper material and controlling synthesis reactions by researchers decreased the rejection of synthetic scaffolds. But in the case of natural scaffolds due to the range of properties, many tests should be applied on the scaffold prior to implantation in order to evaluate functionality in body. In this research, SDS and TritonX100 has been used to decellulize kidney. Then using uniaxial... 

    Investigating the Effect of Lymph Vessel Applying in Organ-On-A-Chip System to Improve the Biomimicry-Inspired Design Strategy

    , M.Sc. Thesis Sharif University of Technology Deir, Sara (Author) ; Yaghmaei, Soheila (Supervisor) ; Mashayekhan, Shohreh (Co-Supervisor)
    In the last decade, the application of organ-on-chip systems to investigate the effectiveness and side effects of various drugs, modele diseases for different tissues has become noticed a lot because these systems are a promising approach to eliminate animal tests and clinical studies on different people. Current conventional methods for drug testing are expensive, time-consuming, and sometimes unreliable. Various organ-on-a-chip systems have been fabricated in order to mimic the conditions of different native tissues in the human body, but only the blood vessel has been considered in most of them while besides blood vessels, as a source to nourish cells, there are lymph vessels as a sink in... 

    Fabrication of Composite Scaffold Composed of Cartilage Extracellular Matrix/Chitosan with High Mechanical Strength for Cartilage Tissue Engineering

    , M.Sc. Thesis Sharif University of Technology Khozaei Ravari, Mojtaba (Author) ; Mashayekhan, Shohreh (Supervisor) ; Baghban Eslami Nejad, Mohammad Reza (Supervisor)
    Methods that has been used for articular defects are faced with many limitations, so new therapies based on tissue engineering were taken into consideration in recent years. However, tissue engineering also encounters challenges regarding optimal scaffold construction and suitable cell source selection. Mature harvested chondrocytes are limited in number and may lose their chondrogenic potential in several cultures, leading to dedifferentiation. In addition, using stem cells also presents unique challenges associated with them, among which hypertrophic differentiation is the most substantial problem. Choosing the appropriate biomaterial similar to the cartilage structure with sufficient... 

    Fabrication of Allograft-derived Scaffold by 3D Bioprinting for Craniofacial Defect

    , M.Sc. Thesis Sharif University of Technology Ashrafnia, Arezoo (Author) ; Mashayekhan, Shohreh (Supervisor)
    Craniofacial bone defects without scarring are a major clinical issue. These critical defects, which can be caused by infection or fracture, cannot be repaired without surgery. The main goal of skull repair is to protect vulnerable structures such as the brain, or it can be due to the improvement of jaw function and beauty. Tissue engineering can offer a new generation solution. The purpose of this study was to construct and characterise a degradable polymer/ bioceramic composite scaffold with allograft powder used in the craniofacial bone. The complexities of the extracellular matrix of humans can be simulated using 3D bioprinting.In this study, tricalcium silicate (TCS) was first... 

    Construction of Micro Carriers Composed of Accelular heart Matrix for Heart Tissue Engineering Application

    , M.Sc. Thesis Sharif University of Technology Esmaeili Pourfarhangi, Kamyar (Author) ; Mashayekhan, Shohreh (Supervisor)
    The heart stoke which happens due to an obstruction in the coronary artery can result in the presence of a dead part on the heart muscle called Myocardial Infarction (MI). MI can lead to next heart strokes and even the death of the patient. So far, a great number of biomaterials consisting of natural and synthetic polymers and Extra Cellular Matrix (ECM) of human body have been recommended for being used in tissue engineering approaches aiming to rehabilitate the infarcted site. The use of ECM is recommended for mimicking the microenvironment of the body as much as possible which can be very helpful in proliferation of the cultured cells. In this project, we fabricated a composite... 

    A three-dimensional micromechanical model of brain white matter with histology-informed probabilistic distribution of axonal fibers

    , Article Journal of the Mechanical Behavior of Biomedical Materials ; Volume 88 , 2018 , Pages 288-295 ; 17516161 (ISSN) Yousefsani, S. A ; Farahmand, F ; Shamloo, A ; Sharif University of Technology
    Elsevier Ltd  2018
    This paper presents a three-dimensional micromechanical model of brain white matter tissue as a transversely isotropic soft composite described by the generalized Ogden hyperelastic model. The embedded element technique, with corrected stiffness redundancy in large deformations, was used for the embedment of a histology-informed probabilistic distribution of the axonal fibers in the extracellular matrix. The model was linked to a multi-objective, multi-parametric optimization algorithm, using the response surface methodology, for characterization of material properties of the axonal fibers and extracellular matrix in an inverse finite element analysis. The optimum hyperelastic... 

    Nonlinear mechanics of soft composites: hyperelastic characterization of white matter tissue components

    , Article Biomechanics and Modeling in Mechanobiology ; Volume 19, Issue 3 , 2020 , Pages 1143-1153 Yousefsani, S. A ; Shamloo, A ; Farahmand, F ; Sharif University of Technology
    Springer  2020
    This paper presents a bi-directional closed-form analytical solution, in the framework of nonlinear soft composites mechanics, for top-down hyperelastic characterization of brain white matter tissue components, based on the directional homogenized responses of the tissue in the axial and transverse directions. The white matter is considered as a transversely isotropic neo-Hookean composite made of unidirectional distribution of axonal fibers within the extracellular matrix. First, two homogenization formulations are derived for the homogenized axial and transverse shear moduli of the tissue, based on definition of the strain energy density function. Next, the rule of mixtures and... 

    Type V collagen in scar tissue regulates the size of scar after heart injury

    , Article Cell ; Volume 182, Issue 3 , 2020 , Pages 545-562.e23 Yokota, T ; McCourt, J ; Ma, F ; Ren, S ; Li, S ; Kim, T. H ; Kurmangaliyev, Y. Z ; Nasiri, R ; Ahadian, S ; Nguyen, T ; Tan, X. H. M ; Zhou, Y ; Wu, R ; Rodriguez, A ; Cohn, W ; Wang, Y ; Whitelegge, J ; Ryazantsev, S ; Khademhosseini, A ; Teitell, M. A ; Chiou, P. Y ; Birk, D. E ; Rowat, A. C ; Crosbie, R. H ; Pellegrini, M ; Seldin, M ; Lusis, A. J ; Deb, A ; Sharif University of Technology
    Cell Press  2020
    Scar tissue size following myocardial infarction is an independent predictor of cardiovascular outcomes, yet little is known about factors regulating scar size. We demonstrate that collagen V, a minor constituent of heart scars, regulates the size of heart scars after ischemic injury. Depletion of collagen V led to a paradoxical increase in post-infarction scar size with worsening of heart function. A systems genetics approach across 100 in-bred strains of mice demonstrated that collagen V is a critical driver of postinjury heart function. We show that collagen V deficiency alters the mechanical properties of scar tissue, and altered reciprocal feedback between matrix and cells induces... 

    Tissue growth into three-dimensional composite scaffolds with controlled micro-features and nanotopographical surfaces

    , Article Journal of Biomedical Materials Research - Part A ; Volume 101, Issue 10 , 2013 , Pages 2796-2807 ; 15493296 (ISSN) Tamjid, E ; Simchi, A ; Dunlop, J. W. C ; Fratzl, P ; Bagheri, R ; Vossoughi, M ; Sharif University of Technology
    Controlling topographic features at all length scales is of great importance for the interaction of cells with tissue regenerative materials. We utilized an indirect three-dimensional printing method to fabricate polymeric scaffolds with pre-defined and controlled external and internal architecture that had an interconnected structure with macro- (400-500 μm) and micro- (∼25 μm) porosity. Polycaprolactone (PCL) was used as model system to study the kinetics of tissue growth within porous scaffolds. The surface of the scaffolds was decorated with TiO2 and bioactive glass (BG) nanoparticles to the better match to nanoarchitecture of extracellular matrix (ECM). Micrometric BG particles were...