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    Modeling and optimization of gelatin-chitosan micro-carriers preparation for soft tissue engineering: using response surface methodology

    , Article Materials Science and Engineering C ; Volume 75 , 2017 , Pages 545-553 ; 09284931 (ISSN) Radaei, P ; Mashayekhan, S ; Vakilian, S ; Sharif University of Technology
    Abstract
    Electrospray ionization is a wide spread technique for producing polymeric microcarriers (MCs) by applying electrostatic force and ionic cross-linker, simultaneously. In this study, fabrication process of gelatin-chitosan MCs and its optimization using the Response Surface Methodology (RSM) is reported. Gelatin/chitosan (G/C) blend ratio, applied voltage and feeding flow rate, their individual and interaction effects on the diameter and mechanical strength of the MCs were investigated. The obtained models for diameter and mechanical strength of MCs have a quadratic relationship with G/C blend ratio, applied voltage and feeding flow rate. Using the desirability curve, optimized G/C blend... 

    Cell Separation via Nano-porous Molecularly Imprinted Polymer

    , M.Sc. Thesis Sharif University of Technology Rahnema Falavarjani, Eiman (Author) ; Abdekhodaie, Mohammad Jafar (Supervisor) ; Nematollah Zade, Ali (Co-Advisor)
    Abstract
    Molecularly imprinted polymers (MIPs) with synthetic recognition sites are capable of detecting and separating chemical species in complex environments. These characteristics are of increasing interest for bioanalytical applications. The chief advantages of MIPs are mechanical and chemical stability, low cost, and ease of preparation. Recently, imprinting technology has been used for fabrication polymer thin films with recognition sites of proteins, plant viruses, and yeasts. Also few investigations applied lithography for synthesis of cell imprinted polymers targeting cell detection and observation of cell morphology.
    For the first time, we demonstrate surface imprinting for the... 

    Simulation, Design and Fabrication of Microfluidic Systems for the Enrichment of Cancer Stem Cells and the Pharmacological Tests

    , M.Sc. Thesis Sharif University of Technology Barisam Haghiri, Maryam (Author) ; Saeedi, Mohammad Saeed (Supervisor) ; Kashaninejad, Navid (Co-Supervisor) ; Trung Nguyen, Nam (Co-Supervisor)
    Abstract
    Cancer is one of the leading causes of death worldwide, and despite all the advances in medical science, there isn't any definitive cure for it, yet. Researchers have recently considered the presence of cancer stem cells with the capability of tumorigenesis, invasion, metastasis, self-renewal, etc. as the main cause of inefficiency of cancer treatment. It means current therapies are able to kill the tumor mass, but they are not successful in confront of cancer stem cells and this causes the disease to recur a while after the apparent recovery. To study these specific cells, in this project, first the population of cancer stem-like cells was increased in the cancer cell mass, in other words,... 

    Modeling and Analysis of Interaction between Tairlored CNT-Graphene Scaffolds and Stem Cell Growth and Differentitation

    , Ph.D. Dissertation Sharif University of Technology Shoghmand Nazarloo, Ahad (Author) ; Ahmadian, Mohammad Taghi (Supervisor) ; Firoozbakhsh, Kheikhosrow (Co-Supervisor)
    Abstract
    Since its successful synthesis as single layer during the past decades, Graphene and its derivatives have been extensively employed by many researchers in various science and engineering fields. The studies to characterize and define graphene behaviour are still in demand to answer the questions around these structures. The unique feathures of graphene such as high strength, good conductivity, large available surface, intoxicity and biocompatibility, has made it a suitable candidate to used in novel structures and materials. In this work, hybrid structures made from graphene and carbon nanotubes are investigated which can be utilized as scaffolds in tissue engineering.After an introduction... 

    Enhanced Waddington landscape model with cell-cell communication can explain molecular mechanisms of self-organization

    , Article Bioinformatics ; Volume 35, Issue 20 , 2019 , Pages 4081-4088 ; 13674803 (ISSN) Fooladi, H ; Moradi, P ; Sharifi Zarchi, A ; Hosein Khalaj, B ; Berger, B ; Sharif University of Technology
    Oxford University Press  2019
    Abstract
    The molecular mechanisms of self-organization that orchestrate embryonic cells to create astonishing patterns have been among major questions of developmental biology. It is recently shown that embryonic stem cells (ESCs), when cultured in particular micropatterns, can self-organize and mimic the early steps of pre-implantation embryogenesis. A systems-biology model to address this observation from a dynamical systems perspective is essential and can enhance understanding of the phenomenon. Results: Here, we propose a multicellular mathematical model for pattern formation during in vitro gastrulation of human ESCs. This model enhances the basic principles of Waddington epigenetic landscape... 

    Design and Fabrication of Centrifugal Microfluidic Disc for Cell Lysis and DNA Extraction

    , M.Sc. Thesis Sharif University of Technology Jalalian, Pourya (Author) ; Saadatmand, Maryam (Supervisor) ; Garshasbi, Masoud (Co-Supervisor)
    Abstract
    Centrifugal microfluidic systems due to their unique properties, including the ease of sample transfer, high controllability, the need for samples and reagents in a small volume scale, the possibility of embedding a complete laboratory and modeling a variety of processes on a disk, they have great potential to be used in the field of point of care diagnosis. Such devices can perform several different processes simultaneously and continuously by using inertial and pneumatic forces as well as a complex network of microchannels. The purpose of this research is to design and build a centrifugal microfluidic disc for lysing amniotic stem cells, followed by DNA extraction, in order to detect fetal... 

    Magnetic resonance imaging tracking of stem cells in vivo using iron oxide nanoparticles as a tool for the advancement of clinical regenerative medicine

    , Article Chemical Reviews ; Volume 111, Issue 2 , November , 2011 , Pages 253-280 ; 00092665 (ISSN) Mahmoudi, M ; Hosseinkhani, H ; Hosseinkhani, M ; Boutry, S ; Simchi, A ; Shane Journeay, W ; Subramani, K ; Laurent, S ; Sharif University of Technology
    2011
    Abstract
    Fetal stem cells, which can be isolated from the organs of fetuses, differentiate along multiple lineages. Their advantages over their adult counterparts include better intrinsic homing and engraftment and lower immunogenicity, and they are less ethically contentious. It is noteworthy that Mesenchymal Stem Cells (MSC) can be activated and mobilized at the site of damaged tissue. Since vascular delivery suffers from a pulmonary first pass effect, direct or systemic injection of MSCs into the damaged tissue is preferred, particularly in the case of versatile tissue ischemia. Ultrasound applies acoustic energy with a frequency above human hearing (20 kHz). Ultrasound imaging or sonography... 

    Injectable polyethylene glycol-laponite composite hydrogels as articular cartilage scaffolds with superior mechanical and rheological properties

    , Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 66, Issue 3 , 2017 , Pages 105-114 ; 00914037 (ISSN) Nojoomi, A ; Tamjid, E ; Simchi, A ; Bonakdar, S ; Stroeve, P ; Sharif University of Technology
    Taylor and Francis Inc  2017
    Abstract
    In this study, injectable PEG-based hydrogels containing Laponite particles with mechanical and structural properties close to the natural articular cartilage are introduced. The nanocomposites are fabricated by imide ring opening reactions utilizing synthesized copolymers containing PEG blocks and nanoclay through a two-step thermal poly-(amic acid) process. Butane diamine is used as nucleophilic reagent and hydrogels with interconnected pores with sizes in the range of 100–250 µm are prepared. Improved viscoelastic properties compared with the conventional PEG hydrogels are shown. Evaluation of cell viability utilizing human mesenchymal stem cells determines cytocompatibility of the... 

    The metabolic network model of primed/naive human embryonic stem cells underlines the importance of oxidation-reduction potential and tryptophan metabolism in primed pluripotency

    , Article Cell and Bioscience ; Volume 9, Issue 1 , 2019 ; 20453701 (ISSN) Yousefi, M ; Marashi, S. A ; Sharifi Zarchi, A ; Taleahmad, S ; Sharif University of Technology
    BioMed Central Ltd  2019
    Abstract
    Background: Pluripotency is proposed to exist in two different stages: Naive and Primed. Conventional human pluripotent cells are essentially in the primed stage. In recent years, several protocols have claimed to generate naive human embryonic stem cells (hESCs). To the best of our knowledge, none of these protocols is currently recognized as the gold standard method. Furthermore, the consistency of the resulting cells from these diverse protocols at the molecular level is yet to be shown. Additionally, little is known about the principles that govern the metabolic differences between naive and primed pluripotency. In this work, using a computational approach, we tried to shed light on... 

    Magnetoelectric nanocomposite scaffold for high yield differentiation of mesenchymal stem cells to neural-like cells

    , Article Journal of Cellular Physiology ; Volume 234, Issue 8 , 2019 , Pages 13617-13628 ; 00219541 (ISSN) Esmaeili, E ; Soleimani, M ; Ghiass, M. A ; Hatamie, S ; Vakilian, S ; Zomorrod, M. S ; Sadeghzadeh, N ; Vossoughi, M ; Hosseinzadeh, S ; Sharif University of Technology
    Wiley-Liss Inc  2019
    Abstract
    While the differentiation factors have been widely used to differentiate mesenchymal stem cells (MSCs) into various cell types, they can cause harm at the same time. Therefore, it is beneficial to propose methods to differentiate MSCs without factors. Herein, magnetoelectric (ME) nanofibers were synthesized as the scaffold for the growth of MSCs and their differentiation into neural cells without factors. This nanocomposite takes the advantage of the synergies of the magnetostrictive filler, CoFe 2 O 4 nanoparticles (CFO), and piezoelectric polymer, polyvinylidene difluoride (PVDF). Graphene oxide nanosheets were decorated with CFO nanoparticles for a proper dispersion in the polymer through... 

    Curcumin-Loaded Starch Micro/Nano particles for biomedical application: the effects of preparation parameters on release profile

    , Article Starch/Staerke ; Volume 71, Issue 5-6 , 2019 ; 00389056 (ISSN) Dehghan Baniani, D ; Zahedifar, P ; Bagheri, R ; Solouk, A ; Sharif University of Technology
    Wiley-VCH Verlag  2019
    Abstract
    Although curcumin is highly cytotoxic against cancer cells, its hydrophobicity and fast degradation at physiological pH limit its effective practical application. To prevent such limitations, inexpensive curcumin-loaded starch particles are synthesized in this research. Particles are prepared by water-in-oil (W/O) miniemulsion technique and an adsorption method is used for curcumin loading. Also, encapsulation efficiency (%EE) is improved by using pluronic F-127 in the drug solution. Particles are characterized, swelling studies are performed, and MTT assays against human adipose mesenchymal stem cells (hAMSCs) and MG-63 cells are utilized for investigations. Results indicate that... 

    A porous hydrogel-electrospun composite scaffold made of oxidized alginate/gelatin/silk fibroin for tissue engineering application

    , Article Carbohydrate Polymers ; Volume 245 , 2020 Hajiabbas, M ; Alemzadeh, I ; Vossoughi, M ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    In the article, a bilayer nanocomposite scaffold made of oxidized alginate (OAL), gelatin (G), and silk fibroin (SF) has been prepared via combining electrospinning, in situ gas foaming, in situ crosslinking and freeze drying methods. The physicochemical and mechanical properties, as well as thermal stability of the proposed composite, have been investigated by SEM, FTIR, XRD, tensile, and TGA analysis. The data indicate that structure and degree of crosslinking play a vital role in adjusting the physical and mechanical properties of composite scaffolds. Further, the authors find a favorable adipose-derived mesenchymal stem cell's (AMSC) attachment and distribution within this novel... 

    Magnetic nanocomposites for biomedical applications

    , Article Advances in Colloid and Interface Science ; Volume 308 , 2022 ; 00018686 (ISSN) Naghdi, M ; Ghovvati, M ; Rabiee, N ; Ahmadi, S ; Abbariki, N ; Sojdeh, S ; Ojaghi, A ; Bagherzadeh, M ; Akhavan, O ; Sharifi, E ; Rabiee, M ; Saeb, M. R ; Bolouri, K ; Webster, T. J ; Zare, E. N ; Zarrabi, A ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Tissue engineering and regenerative medicine have solved numerous problems related to the repair and regeneration of damaged organs and tissues arising from aging, illnesses, and injuries. Nanotechnology has further aided tissue regeneration science and has provided outstanding opportunities to help disease diagnosis as well as treat damaged tissues. Based on the most recent findings, magnetic nanostructures (MNSs), in particular, have emerged as promising materials for detecting, directing, and supporting tissue regeneration. There have been many reports concerning the role of these nano-building blocks in the regeneration of both soft and hard tissues, but the subject has not been... 

    Silica nanoparticle surface chemistry: An important trait affecting cellular biocompatibility in two and three dimensional culture systems

    , Article Colloids and Surfaces B: Biointerfaces ; Volume 182 , 2019 ; 09277765 (ISSN) Hasany, M ; Taebnia, N ; Yaghmaei, S ; Shahbazi, M. A ; Mehrali, M ; Dolatshahi Pirouz, A ; Arpanaei, A ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    Great advantages bestowed by mesoporous silica nanoparticles (MSNs) including high surface area, tailorable pore diameter and surface chemistry, and large pore volume render them as efficient tools in biomedical applications. Herein, MSNs with different surface chemistries were synthesized and investigated in terms of biocompatibility and their impact on the morphology of bone marrow-derived mesenchymal stem cells both in 2D and 3D culture systems. Bare MSNs (BMSNs) were synthesized by template removing method using tetraethylorthosilicate (TEOS) as a precursor. The as-prepared BMSNs were then used to prepare amine-functionalized (AMSNs), carboxyl-functionalized (CMSNs) and polymeric... 

    Study of epithelial differentiation and protein expression of keratinocyte-mesenchyme stem cell co-cultivation on electrospun nylon/B. vulgaris extract composite scaffold

    , Article Materials Science and Engineering C ; Volume 75 , 2017 , Pages 653-662 ; 09284931 (ISSN) Hosseinzadeh, S ; Soleimani, M ; Vossoughi, M ; Ranjbarvan, P ; Hamedi, S ; Zamanlui, S ; Mahmoudifard, M ; Sharif University of Technology
    Abstract
    Employing of the composite electrospun scaffold containing herbal extract in conjugation with co-culturing of cells can open up new window to the design of efficient biomaterials for skin tissue regeneration. Here, we introduce the synergistic effect of composite electrospun nanofibrous scaffold of nylon66 loaded with Beta vulgaris (B. vulgaris) (extract of beet roots, a plants whose widely used in Iranian folk medicine as wound healing medicine) and co-culture of mesenchymal stem-cells (MSCs)-human keratinocyte (H-keratino) differentiation towards epithelial lineage. In vitro biocompatibility was examined through MTT assay and epithelial differentiation checked by real-time PCR and... 

    A microfabricated platform for the study of chondrogenesis under different compressive loads

    , Article Journal of the Mechanical Behavior of Biomedical Materials ; Volume 78 , 2018 , Pages 404-413 ; 17516161 (ISSN) Kowsari Esfahan, R ; Jahanbakhsh, A ; Saidi, M. S ; Bonakdar, S ; Sharif University of Technology
    Elsevier Ltd  2018
    Abstract
    Microfluidic devices are beneficial in miniaturizing and multiplexing various cellular assays in a single platform. Chondrogenesis is known to pertain to chemical, topographical, and mechanical cues in the microenvironment. Mechanical cues themselves have numerous parameters such as strain magnitude, frequency, and stimulation time. Effects of different strain magnitudes on the chondrogenic differentiation of adult stem cells have not been explored thoroughly. Here, a new multilayer microdevice is presented for the unidirectional compressive stimulation of cells in a three-dimensional cell culture. Numerical simulations were performed to evaluate and optimize the design. Results showed a... 

    MicroRNA profiling reveals important functions of miR-125b and let-7a during human retinal pigment epithelial cell differentiation

    , Article Experimental Eye Research ; Volume 190 , 2020 Shahriari, F ; Satarian, L ; Moradi, S ; Sharifi Zarchi, A ; Günther, S ; Kamal, A ; Totonchi, M ; Mowla, S. J ; Braun, T ; Baharvand, H ; Sharif University of Technology
    Academic Press  2020
    Abstract
    Retinal pigment epithelial (RPE) cells are indispensable for eye organogenesis and vision. To realize the therapeutic potential of in vitro-generated RPE cells for cell-replacement therapy of RPE-related retinopathies, molecular mechanisms of RPE specification and maturation need to be investigated. So far, many attempts have been made to decipher the regulatory networks involved in the differentiation of human pluripotent stem cells into RPE cells. Here, we exploited a highly-efficient RPE differentiation protocol to determine global expression patterns of microRNAs (miRNAs) during human embryonic stem cell (hESC) differentiation into RPE using small RNA sequencing. Our results revealed a... 

    Experimental Investigation on Growth and Control of Animal Cells Attached on Scaffold

    , M.Sc. Thesis Sharif University of Technology Solmaz, Naseri (Author) ; Vossoughi, Manoochehr (Supervisor) ; Alamzadeh, Iran (Co-Advisor)
    Abstract
    Major bone defects resulted from diseases or hurts that can not heal naturally, requaire bone transplantation. golden standard for transplantation is autologus one but it has some disad-vantages such as economic burden, the lack of graft source, surgery on patient, and so on. so exploring altrnative ways led to exploit stem cells.traditionally bone marrow mesenchymal stem cells (MSCs) used for stem cell-bsaed bone regeneration. bone marrow aspiration to aquaire stem cells is painfull and give a population of cells such as hematopoetic cells that requaire to seperate and can not be handled in first passages. MSCs can be substituted by multipotent adipose tissue-derived stem cells (ADSCs) in... 

    Study and Fabrication of a Microfluidic System to Investigate Stem Cell Differentiation

    , M.Sc. Thesis Sharif University of Technology Motmaen Esfahani, Shayan (Author) ; Vosoughi, Manouchehr (Supervisor) ; Alemzadeh, Iran (Supervisor)
    Abstract
    In recent years, many studies have conducted research about stem cells due to their prominent features such as proliferation and differentiation. By changing the specific parameters of the cellular micro-environment, it is possible to determine the stem cells fate and thereby use them in medical affairs. For this purpose, various devices and methods have been designeds such as microfluidic devices and scaffolds. The microfluidic devices has been especially focuced in the researchs due to their unique features, like the possibility of testing with small amounts of samples, the creation and control of low cost cellular micro-environment and low practical time. Two-dimensional scaffolds made up... 

    Fabricating Graphene Paper and Determining Its Electrical and Mechanical Properties and Using It for Proliferation and Differentiation of Neural Stem Cells

    , M.Sc. Thesis Sharif University of Technology Akbar Shirazian, Soheil (Author) ; Akhavan, Omid (Supervisor)
    Abstract
    Nowadays, tissue engineering and stem cells-based therapies have outlined a promising prospect in neural networks regeneration. But it usually requires biocompatible and conductive scaffolds for culturing neural stem cells and directing their differentiation toward the neurons. Graphene due to its unique physical and chemical properties has attracted much interest in tissue engineering. For this purpose, in this study biocompatible graphene oxide foams have been used for neural stem cell culturing. For the first time, graphene oxide foam were fabricated by precipitation of chemically exfoliated graphene oxide sheets in an aqueous suspension onto the PET substrate at ~80 oC under UV...