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    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
    2013
    Abstract
    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... 

    The synergistic effect of surface topography and sustained release of TGF-β1 on myogenic differentiation of human mesenchymal stem cells

    , Article Journal of Biomedical Materials Research - Part A ; Volume 104, Issue 7 , 2016 , Pages 1610-1621 ; 15493296 (ISSN) Moghadasi Boroujeni, S ; Mashayekhan, S ; Vakilian, S ; Ardeshirylajimi, A ; Soleimani, M ; Sharif University of Technology
    John Wiley and Sons Inc 
    Abstract
    A combination of topographical cues and controlled release of biochemical factors is a potential platform in controlling stem cells differentiation. In this study the synergistic effect of nanotopography and sustained release of biofunctional transforming growth factor beta 1 (TGF-β1) on differentiation of human Wharton's Jelly-derived mesenchymal stem cell (hWJ-derived UC-MSCs) toward myogenic lineage was investigated. In order to achieve a sustained release of TGF-β1, this factor was encapsulated within chitosan nanoparticles. Afterwards the aligned composite mats were fabricated using poly-E-caprolacton (PCL) containing TGF-β1-loaded chitosan nanoparticles and poly-L-lactic acid (PLLA).... 

    Thermoplastic starch/ethylene vinyl alcohol/forsterite nanocomposite as a candidate material for bone tissue engineering

    , Article Materials Science and Engineering C ; Volume 69 , 2016 , Pages 301-310 ; 09284931 (ISSN) Mahdieh, Z ; Bagheri, R ; Eslami, M ; Amiri, M ; Shokrgozar, M. A ; Mehrjoo, M ; Sharif University of Technology
    Elsevier Ltd 
    Abstract
    Recently, biodegradable polymers such as starch based blends have been well renowned in the biomedical field. Studies have considered them suitable for bone scaffolds, bone cements, tissue engineering scaffolds, drug delivery systems and hydrogels. The aim of this study was to synthesize nanocomposite biomaterial consisting a blend of thermoplastic starch and ethylene vinyl alcohol as the polymer matrix, and nano-structured forsterite as the ceramic reinforcing phase for bone tissue engineering applications. Furthermore, vitamin E was applied as a thermal stabilizer during melt compounding. Extrusion and injection molding were incorporated for melt blending and shaping of samples,... 

    The nanofibrous PAN-PANi scaffold as an efficient substrate for skeletal muscle differentiation using satellite cells

    , Article Bioprocess and Biosystems Engineering ; Volume 39, Issue 7 , 2016 , Pages 1163-1172 ; 16157591 (ISSN) Hosseinzadeh, S ; Mahmoudifard, M ; Mohamadyar Toupkanlou, F ; Dodel, M ; Hajarizadeh, A ; Adabi, M ; Soleimani, M ; Sharif University of Technology
    Springer Verlag 
    Abstract
    Among polymers, polyaniline (PANi) has been introduced as a good candidate for muscle regeneration due to high conductivity and also biocompatibility. Herein, for the first time, we report the use of electrospun nanofibrous membrane of PAN-PANi as efficient scaffold for muscle regeneration. The prepared PAN-PANi electrospun nanofibrous membrane was characterized by scanning electron microscopy (SEM), Attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR) and tensile examination. The softer scaffolds of non-composite electrospun nanofibrous PAN govern a higher rate of cell growth in spite of lower differentiation value. On the other hand, PAN-PANi electrospun... 

    The impact of zirconium oxide nanoparticles content on alginate dialdehyde-gelatin scaffolds in cartilage tissue engineering

    , Article Journal of Molecular Liquids ; Volume 335 , 2021 ; 01677322 (ISSN) Ghanbari, M ; Salavati Niasari, M ; Mohandes, F ; Firouzi, Z ; Mousavi, S.-D ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    The desire to regenerate and repair native tissues can be immediately performed by multiple tissue engineering procedures. Gelatin and alginate are biocompatible and biodegradable polymers. The addition of ZrO2 nanoparticles (NPs) into the alginate-gelatin hydrogel is considered to improve mechanical and chemical properties. Therefore, nanocomposite hydrogels have been manufactured by the freeze-drying procedure utilizing oxidized alginate-gelatin with ZrO2 NPs as a reinforcement. The fabricated nanocomposite hydrogels were character-ized by FTIR, FESEM, and rheometer. The hydrogels containing a higher ZrO2 NPs content (1.5%) have better mechanical properties than the hydrogels without NPs.... 

    The fabrication and characterization of bioactive Akermanite/Octacalcium phosphate glass-ceramic scaffolds produced via PDC method

    , Article Ceramics International ; 2020 Abdollahi, S ; Paryab, A ; Khalilifard, R ; Anousheh, M ; Malek Khachatourian, A ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    In the present study, a bioactive silicate-phosphate glass-ceramic scaffold was fabricated via the polymer-derived ceramics (PDC) method. K2HPO4 phosphate salt was used as the P2O5 precursor in this method. The effect of K2HPO4 wt% and heat treatment temperatures (900–1100 °C) was evaluated. It was observed that although increasing the wt% of K2HPO4 led to the formation of scaffolds with higher densities and strengths, it could also increase the formation of the calcium phase, which could result in improper release behavior of scaffolds. On the other hand, higher heat treatment temperatures enhanced the strength of the scaffolds but eliminated the bioactive octacalcium phosphate (OCP) phase.... 

    The fabrication and characterization of bioactive Akermanite/Octacalcium phosphate glass-ceramic scaffolds produced via PDC method

    , Article Ceramics International ; Volume 47, Issue 5 , 2021 , Pages 6653-6662 ; 02728842 (ISSN) Abdollahi, S ; Paryab, A ; Khalilifard, R ; Anousheh, M ; Malek Khachatourian, A ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    In the present study, a bioactive silicate-phosphate glass-ceramic scaffold was fabricated via the polymer-derived ceramics (PDC) method. K2HPO4 phosphate salt was used as the P2O5 precursor in this method. The effect of K2HPO4 wt% and heat treatment temperatures (900–1100 °C) was evaluated. It was observed that although increasing the wt% of K2HPO4 led to the formation of scaffolds with higher densities and strengths, it could also increase the formation of the calcium phase, which could result in improper release behavior of scaffolds. On the other hand, higher heat treatment temperatures enhanced the strength of the scaffolds but eliminated the bioactive octacalcium phosphate (OCP) phase.... 

    The fabrication and characterization of bioactive Akermanite/Octacalcium phosphate glass-ceramic scaffolds produced via PDC method

    , Article Ceramics International ; Volume 47, Issue 5 , 2021 , Pages 6653-6662 ; 02728842 (ISSN) Abdollahi, S ; Paryab, A ; Khalilifard, R ; Anousheh, M ; Malek Khachatourian, A ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    In the present study, a bioactive silicate-phosphate glass-ceramic scaffold was fabricated via the polymer-derived ceramics (PDC) method. K2HPO4 phosphate salt was used as the P2O5 precursor in this method. The effect of K2HPO4 wt% and heat treatment temperatures (900–1100 °C) was evaluated. It was observed that although increasing the wt% of K2HPO4 led to the formation of scaffolds with higher densities and strengths, it could also increase the formation of the calcium phase, which could result in improper release behavior of scaffolds. On the other hand, higher heat treatment temperatures enhanced the strength of the scaffolds but eliminated the bioactive octacalcium phosphate (OCP) phase.... 

    The effect of Ag incorporation on the characteristics of the polymer derived bioactive silicate phosphate glass-ceramic scaffolds

    , Article Boletin de la Sociedad Espanola de Ceramica y Vidrio ; 2021 ; 03663175 (ISSN) Paryab, A ; Godary, T ; Khalilifard, R ; Malek Khachatourian, A ; Abdollahi, F ; Abdollahi, S ; Sharif University of Technology
    Sociedad Espanola de Ceramica y Vidrio  2021
    Abstract
    In the bone tissue engineering field (BTE), it is of significant importance to develop bioactive multifunctional scaffolds with enhanced osteoconductivity, osteoinductivity, and antibacterial properties required for lost bone tissue regeneration. In this work, a bioactive glass-ceramic scaffold was manufactured via a novel polymer-derived ceramics (PDC) manufacturing method. To gain antibacterial properties, the silver ions were incorporated in controlled amount along with other precursors in the PDC processing stage. Microstructural and structural properties of the fabricated silicate-phosphate glass-ceramic scaffold were evaluated by scanning electron microscopy (SEM) equipped with energy... 

    The different fate of satellite cells on conductive composite electrospun nanofibers with graphene and graphene oxide nanosheets

    , Article Biomedical Materials (Bristol) ; Volume 11, Issue 2 , 2016 ; 17486041 (ISSN) Mahmoudifard, M ; Soleimani, M ; Hatamie, S ; Zamanlui, S ; Ranjbarvan, P ; Vossoughi, M ; Hosseinzadeh, S ; Sharif University of Technology
    Institute of Physics Publishing  2016
    Abstract
    Electrospinning of composite polymer solutions provides fantastic potential to prepare novel nanofibers for use in a variety of applications. The addition of graphene (G) and graphene oxide (GO) nanosheets to bioactive polymers was found to enhance their conductivity and biocompatibility. Composite conductive nanofibers of polyaniline (PANI) and polyacrylonitrile (PAN) with G and GO nanosheets were prepared by an electrospinning process. The fabricated membranes were investigated by physical and chemical examinations including scanning electron microscopy (SEM), Raman spectroscopy, x-ray diffraction (XRD) and tensile assay. The muscle satellite cells enriched by a pre-plating technique were... 

    Study of hole-transporter-free perovskite solar cells based on fully printable components

    , Article Micromachines ; Volume 10, Issue 4 , 2019 ; 2072666X (ISSN) Raminafshar, C ; Raptis, D ; Mohammadi, M. R ; Lianos, P ; Sharif University of Technology
    MDPI AG  2019
    Abstract
    Hole-transporter-free perovskite solar cells carrying a carbon back contact electrode provide the possibility of making full printable low cost and stable devices, even though their efficiency is substantially lower than those made in the standard configuration. The present work searched for simple and easy routes for constructing such devices, demonstrating that organic components do enhance device efficiency but only to a level that is not worth the trouble nor the cost. Devices based on a triple mesoporous layer of titania/zirconia/carbon with perovskite infiltration gave an efficiency of 10.7%. After 180 days of storing under ambient conditions, a small loss of efficiency has been... 

    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... 

    Stereolithography 3D bioprinting method for fabrication of human corneal stroma equivalent

    , Article Annals of Biomedical Engineering ; Volume 48, Issue 7 , June , 2020 , Pages 1955-1970 Mahdavi, S. S ; Abdekhodaie, M. J ; Kumar, H ; Mashayekhan, S ; Baradaran Rafii, A ; Kim, K ; Sharif University of Technology
    Springer  2020
    Abstract
    Abstract: 3D bioprinting technology is a promising approach for corneal stromal tissue regeneration. In this study, gelatin methacrylate (GelMA) mixed with corneal stromal cells was used as a bioink. The visible light-based stereolithography (SLA) 3D bioprinting method was utilized to print the anatomically similar dome-shaped structure of the human corneal stroma. Two different concentrations of GelMA macromer (7.5 and 12.5%) were tested for corneal stroma bioprinting. Due to high macromer concentrations, 12.5% GelMA was stiffer than 7.5% GelMA, which made it easier to handle. In terms of water content and optical transmittance of the bioprinted scaffolds, we observed that scaffold with... 

    Size-dependent genotoxicity of graphene nanoplatelets in human stem cells

    , Article Biomaterials ; Volume 33, Issue 32 , 2012 , Pages 8017-8025 ; 01429612 (ISSN) Akhavan, O ; Ghaderi, E ; Akhavan, A ; Sharif University of Technology
    2012
    Abstract
    Reduced graphene oxide nanoplatelets (rGONPs) were synthesized by sonication of covalently PEGylated GO sheets followed by a chemical reduction using hydrazine and bovine serum albumin. Human mesenchymal stem cells (hMSCs), as a fundamental factor in tissue engineering, were isolated from umbilical cord blood (as a recently proposed source for extracting fresh hMSCs) to investigate, for the first time, the size-dependent cyto- and geno-toxic effects of the rGONPs on the cells. The cell viability test showed significant cell destructions by 1.0 μg/mL rGONPs with average lateral dimensions (ALDs) of 11±4 nm, while the rGO sheets with ALDs of 3.8±0.4 μm could exhibit a significant cytotoxic... 

    Simulation of the effects of oxygen carriers and scaffold geometry on oxygen distribution and cell growth in a channeled scaffold for engineering myocardium

    , Article Mathematical Biosciences ; Volume 294 , 2017 , Pages 160-171 ; 00255564 (ISSN) Zehi Mofrad, A ; Mashayekhan, S ; Bastani, D ; Sharif University of Technology
    Abstract
    This study proposes a mathematical model to evaluate the impact of oxygen carriers and scaffold geometry on oxygen distribution and cell growth in a 3D cardiac construct using computational fluid dynamics (CFD). Flow equations, oxygen balance equation and cell balance equation were solved using special initial and boundary conditions. The modeling results revealed that 55% increase in cardiac cell density occurred by using 6.4% perfluorocarbon oxygen carrier (PFC) compared to pure culture medium without PFC supplementation. Moreover, the effects of the scaffold geometry on cell density were examined by changing the channel numbers and the construct length. A 30% increase in the average cells... 

    Rolled graphene oxide foams as three-dimensional scaffolds for growth of neural fibers using electrical stimulation of stem cells

    , Article Carbon ; Volume 97 , 2016 , Pages 71-77 ; 00086223 (ISSN) Akhavan, O ; Ghaderi, E ; Shirazian, S. A ; Rahighi, R ; Sharif University of Technology
    Elsevier Ltd 
    Abstract
    Graphene oxide foam (GOF) layers with thicknesses of ∼15-50 μm and density of ∼10 graphene oxide (GO) sheets/μm were fabricated by precipitation of chemically exfoliated GO sheets in an aqueous suspension at ∼80 °C under UV irradiation. Then, rolled GOFs with desirable scales were developed as electrically conductive 3D-scaffolds and applied in directional growth of neural fibers, through differentiation of human neural stem cells (hNSCs) into neurons under an electrical stimulation. X-ray photoelectron spectroscopy indicated that the UV irradiation resulted in partial deoxygenation of the layers. Scanning electron microscopy and Raman spectroscopy confirmed the presence of multilayer GO... 

    Processing and properties of nanofibrous bacterial cellulose-containing polymer composites: a review of recent advances for biomedical applications

    , Article Polymer Reviews ; Volume 60, Issue 1 , 2020 , Pages 144-170 Eslahi, N ; Mahmoodi, A ; Mahmoudi, N ; Zandi, N ; Simchi, A ; Sharif University of Technology
    Taylor and Francis Inc  2020
    Abstract
    Bacterial cellulose (BC) is an extracellular natural polymer produced by many microorganisms and its properties could be tailored via specific fabrication methods and culture conditions. There is a growing interest in BC derived materials due to the main features of BC such as porous fibrous structure, high crystallinity, impressive physico-mechanical properties, and high water content. However, pristine BC lacks some features, limiting its practical use in varied applications. Thus, fabrication of BC composites has been attempted to overcome these constraints. This review article overviews most recent advance in the development of BC composites and their potential in biomedicine including... 

    Pressure-engineered electrophoretic deposition for gentamicin loading within osteoblast-specific cellulose nanofiber scaffolds

    , Article Materials Chemistry and Physics ; Volume 272 , 2021 ; 02540584 (ISSN) Rahighi, R ; Panahi, M ; Akhavan, O ; Mansoorianfar, M ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Multi-component nanocomposite thin films (composed of cellulose nanofiber (CNF), alginate, bioglass nanoparticles (BG NPs) and gentamicin) were prepared by using cathodic electrophoretic deposition (EPD) under different isostatic pressures of 10−2 mbar (LP), atmospheric (AP), and 5 bar (HP). According to thermal gravity analysis, larger amounts of CNF and alginate could be deposited on the surface at the AP condition in comparison with the LP and HP conditions. On the other hand, higher amounts of the BG NPs could be deposited at the LP condition as compared to the other conditions. The drug (gentamicin) loading/releasing of the samples prepared at the HP condition was found to be higher... 

    Preparation of biodegradable gelatin/PVA porous scaffolds for skin regeneration

    , Article Artificial Cells, Nanomedicine and Biotechnology ; 2016 , Pages 1-8 ; 21691401 (ISSN) Mahnama, H ; Dadbin, S ; Frounchi, M ; Rajabi, S ; Sharif University of Technology
    Taylor and Francis Ltd  2016
    Abstract
    Porous scaffolds composed of gelatin/poly (vinyl alcohol), (Gel/PVA), were prepared using combination of freeze gelation and freeze drying methods. The effect of polymer concentration, gelatin/PVA ratio, and glutaraldehyde/gelatin ratio (GA/Gel) was investigated on morphology of pores, swelling ratio, biodegradation, and skin cell culture. At optimum preparation conditions the scaffolds had uniform pore size distributions showing high swelling ratio of 23.6. The scaffolds were of biodegradable nature and almost degraded in 28 days. Human dermal fibroblast cells (HDF) were cultured on the scaffolds and MTS assay was conducted to evaluate the influence of PVA on growth and proliferation of the... 

    Preparation of biodegradable gelatin/PVA porous scaffolds for skin regeneration

    , Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 45, Issue 5 , 2017 , Pages 928-935 ; 21691401 (ISSN) Mahnama, H ; Dadbin, S ; Frounchi, M ; Rajabi, S ; Sharif University of Technology
    Taylor and Francis Ltd  2017
    Abstract
    Porous scaffolds composed of gelatin/poly (vinyl alcohol), (Gel/PVA), were prepared using combination of freeze gelation and freeze drying methods. The effect of polymer concentration, gelatin/PVA ratio, and glutaraldehyde/gelatin ratio (GA/Gel) was investigated on morphology of pores, swelling ratio, biodegradation, and skin cell culture. At optimum preparation conditions the scaffolds had uniform pore size distributions showing high swelling ratio of 23.6. The scaffolds were of biodegradable nature and almost degraded in 28 days. Human dermal fibroblast cells (HDF) were cultured on the scaffolds and MTS assay was conducted to evaluate the influence of PVA on growth and proliferation of the...