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    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... 

    Do the soft tissues located outside tibiofemoral joint have a role in bearing the compressive loads of the joint? An in-vitro study on sheep stifle joints

    , Article Gazzetta Medica Italiana Archivio per le Scienze Mediche ; Volume 172, Issue 7-8 , 2013 , Pages 595-601 ; 03933660 (ISSN) Hakkak, F ; Rostami, M ; Parnianpour, M ; Jabalameli, M ; Sharif University of Technology
    2013
    Abstract
    Aim. The compressive loads on the tibiofemoral joint are normally assumed to be borne solely via contact and pressing of the cartilage surfaces of tibia and femur. However, recent findings suggest that non-contact load-bearing mechanisms are active in the joint as well. In this context, a non-contact load-bearing mechanism involving soft tissue connections outside the tibiofemoral joint has been hypothesized as well. This paper addresses the validity of this hypothesis and the possible involvement of several soft tissue connections outside the joint. Methods. Sheep stifle (knee) joints were studied in vitro. The specimens were loaded in fixed displacement. Various soft tissues outside the... 

    Comparison of strengths of five internal fixation methods used after bilateral sagittal split ramus osteotomy: An in vitro study

    , Article Dental Research Journal ; Volume 17, Issue 4 , 2020 , Pages 258-265 Sarkarat, F ; Ahmady, A ; Farahmand, F ; Fateh, A ; Kahali, R ; Nourani, A ; Rakhshan, V ; Sharif University of Technology
    Wolters Kluwer Medknow Publications  2020
    Abstract
    Results on the strength and displacement of internal fixation methods for bilateral sagittal split ramus osteotomy are controversial, and some designs have not been adequately studied. Therefore, this study was conducted to compare techniques using bicortical or monocortical screws. Materials and Methods: In this in vitro study, 35 sheep hemi-mandibles were randomly assigned to five groups of seven each: fixation using (1) a 13 × 2 screw, (2) two 13 × 2 screws (arranged vertically), (3) three 13 × 2 screws, (4) 1 plate with 4 holes and four monocortical screws, and (5) a Y-shaped plate and five monocortical screws. Specimens underwent vertical forces until failure. Breakage forces and... 

    Comparison of mechanical properties in interference screw fixation technique and organic anterior cruciate ligament reconstruction method: a biomechanical study

    , Article BMC Musculoskeletal Disorders ; Volume 22, Issue 1 , 2021 ; 14712474 (ISSN) Borjali, A ; Nourani, A ; Moeinnia, H ; Mohseni, M ; Korani, H ; Ghias, N ; Chizari, M ; Sharif University of Technology
    BioMed Central Ltd  2021
    Abstract
    Background: Bone and Site Hold Tendon Inside (BASHTI) technique is an organic implant-less technique for anterior cruciate ligament (ACL) reconstruction with some clinical advantages, such as speeding up the healing process, over implantable techniques. The study aims to compare the mechanical properties of BASHTI technique with the conventional interference screw technique. Methods: To investigate the mechanical properties, 20 in-vitro experimental tests were conducted. Synthetic dummy bone, along with fresh digital bovine tendons, as a graft, were used for experiments. Three loading steps were applied to all specimens, including a preconditioning, a main cyclic, and a pull-out loading.... 

    Simulation of blood oxygenation in capillary membrane oxygenators using modified sulfite solution

    , Article Biophysical Chemistry ; Vol. 195, issue , Dec , 2014 , p. 8-15 Tabesh, H ; Amoabediny, G ; Rasouli, A ; Ramedani, A ; Poorkhalil, A ; Kashefi, A ; Mottaghy, K ; Sharif University of Technology
    Abstract
    Blood oxygenation is the main performance characteristic of capillary membrane oxygenators (CMOs). Handling of natural blood in in vitro investigations of CMOs is quite complex and time-consuming. Since the conventional blood analog fluids (e.g. water/glycerol) lack a substance with an affinity to capture oxygen comparable to hemoglobin's affinity, in this study a novel approach using modified sulfite solution is proposed to address this challenge. The solution comprises sodium sulfite as a component, simulating the role of hemoglobin in blood oxygenation. This approach is validated by OTR (oxygen transfer rate) measured using native porcine blood, in two types of commercially available... 

    Preparation and evaluation of bioactive and compatible starch based superabsorbent for oral drug delivery systems

    , Article Journal of Drug Delivery Science and Technology ; Volume 23, Issue 5 , 2013 , Pages 511-517 ; 17732247 (ISSN) Pourjavadi, A ; Ebrahimi, A. A ; Barzegar, S ; Sharif University of Technology
    2013
    Abstract
    Novel types of highly swelling hydrogels (superabsorbent) were prepared by grafting crosslinked poly acrylic acid-co-2-hydroxyethylmetacrylate (PAA-co-HEMA) chains onto starch through a free radical polymerization method. The effect of grafting variables (i.e., concentration of methylenebisacrylamide (MBA), acrylic acid/2-hydroxy methymetacrylate (AA/HEMA) weight ratio, ammonium persulfate (APS), starch, neutralization percent, were systematically optimized to achieve a hydrogel with a maximum swelling capacity. The superabsorbent (SAP) formation was confirmed by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The controlled-release behavior of... 

    Directional migration and differentiation of neural stem cells within three-dimensional microenvironments

    , Article Integrative Biology (United Kingdom) ; Volume 7, Issue 3 , Jan , 2015 , Pages 335-344 ; 17579694 (ISSN) Shamloo, A ; Heibatollahi, M ; Mofrad, M. R. K ; Sharif University of Technology
    Royal Society of Chemistry  2015
    Abstract
    Harnessing neural stem cells to repair neuronal damage is a promising potential treatment for neuronal diseases. To enable future therapeutic efficacy, the survival, proliferation, migration and differentiation of neural stem/progenitor cells (NPCs) should be accurately studied and optimized in in vitro platforms before transplanting these cells into the body for treatment purposes. Such studies can determine the appropriate quantities of the biochemical and biomechanical factors needed to control and optimize NPC behavior in vivo. In this study, NPCs were cultured within a microfluidic device while being encapsulated within the collagen matrix. The migration and differentiation of NPCs were... 

    Folate-conjugated pH-responsive nanocarrier designed for active tumor targeting and controlled release of gemcitabine

    , Article Pharmaceutical Research ; Volume 33, Issue 2 , 2016 , Pages 417-432 ; 07248741 (ISSN) Pourjavadi, A ; Mazaheri Tehrani, Z ; Abedin Moghanaki, A ; Sharif University of Technology
    Springer New York LLC 
    Abstract
    Purpose: The prime end of this study was to design a novel pH-sensitive as well as a PEGylated dendritic nanocarrier for both controllable and traceable gemcitabine delivery to cancerous cells. To accomplish this goal, we took advantage of a hybrid of nanoparticles including: mesoporous silica, graphene oxide and magnetite. Methods: The nanocarrier was prepared in a multi-step synthesis route. First, magnetite mesoporous silica was deposited on the graphene oxide matrix. Then, polyamidoamine dendrimers (up to generation 1.5) with pentaethylene hexamine end groups were grafted on the surface of the nanoparticles. In order to enhance the biostability, and as the next step, the nanocarrier was... 

    Fabrication of porous scaffolds with decellularized cartilage matrix for tissue engineering application

    , Article Biologicals ; Volume 48 , 2017 , Pages 39-46 ; 10451056 (ISSN) Nasiri, B ; Mashayekhan, S ; Sharif University of Technology
    Academic Press  2017
    Abstract
    Due to the avascular nature of articular cartilage, damaged tissue has little capacity for spontaneous healing. Three-dimensional scaffolds have potential for use in tissue engineering approach for cartilage repair. In this study, bovine cartilage tissue was decellularized and chemically crosslinked hybrid chitosan/extracellular matrix (ECM) scaffolds were fabricated with different ECM weight ratios by simple freeze drying method. Various properties of chitosan/ECM scaffolds such as microstructure, mechanical strength, swelling ratio, and biodegradability rate were investigated to confirm improved structural and biological characteristics of chitosan scaffolds in the presence of ECM. The... 

    In vitro biological outcome of laser application for modification or processing of titanium dental implants

    , Article Lasers in Medical Science ; Volume 32, Issue 5 , 2017 , Pages 1197-1206 ; 02688921 (ISSN) Hindy, A ; Farahmand, F ; Tabatabaei, F. S ; Sharif University of Technology
    Abstract
    There are numerous functions for laser in modern implant dentistry including surface treatment, surface coating, and implant manufacturing. As laser application may potentially improve osseointegration of dental implants, we systematically reviewed the literature for in vitro biological responses to laser-modified or processed titanium dental implants. The literature was searched in PubMed, ISI Web, and Scopus, using keywords “titanium dental implants,” “laser,” “biocompatibility,” and their synonyms. After screening the 136 references obtained, 28 articles met the inclusion criteria. We found that Nd:YAG laser was the most commonly used lasers in the treatment or processing of titanium... 

    Anti-HER2 VHH targeted magnetoliposome for intelligent magnetic resonance imaging of breast cancer cells

    , Article Cellular and Molecular Bioengineering ; Volume 10, Issue 3 , 2017 , Pages 263-272 ; 18655025 (ISSN) Khaleghi, S ; Rahbarizadeh, F ; Ahmadvand, D ; Madaah Hosseini, H. R ; Sharif University of Technology
    Abstract
    The combination of liposomes with magnetic nanoparticles, because of their strong effect on T2 relaxation can open new ways in the innovative cancer therapy and diagnosis. In order to design an intelligent contrast agent in MRI, we chose anti-HER2 nanobody the smallest fully functional antigen-binding fragments evolved from the variable domain, the VHH, of a camel heavy chain-only antibody. These targeted magnetoliposomes bind to the HER2 antigen which is highly expressed on breast and ovarian cancer cells so reducing the side effects as well as increasing image contrast and effectiveness. Cellular iron uptake analysis and in vitro MRI of HER2 positive cells incubated with targeted... 

    Fabrication and characterization of a starch-based nanocomposite scaffold with highly porous and gradient structure for bone tissue engineering

    , Article Biomedical Physics and Engineering Express ; Volume 4, Issue 5 , 2018 ; 20571976 (ISSN) Mirab, F ; Eslamian, M ; Bagheri, R ; Sharif University of Technology
    Institute of Physics Publishing  2018
    Abstract
    Starch based scaffolds are considered as promising biomaterials for bone tissue engineering. In this study, a highly porous starch/polyvinyl alcohol (PVA) based nanocomposite scaffold with a gradient pore structure was made by incorporating different bio-additives, including citric acid, cellulose nanofibers, and hydroxyapatite (HA) nanoparticles. The scaffold was prepared by employing unidirectional and cryogenic freeze-casting and subsequently freeze-drying methods. Fourier transform infrared (FTIR) spectroscopy confirmed the cross-linking of starch and PVA molecules through multiple esterification phenomenon in the presence of citric acid as a cross-linking agent. Field emission scanning... 

    Evaluation of bioactivity and biocompatibility of silk fibroin/TiO2 nanocomposite

    , Article Journal of Medical and Biological Engineering ; Volume 38, Issue 1 , February , 2018 , Pages 99-105 ; 16090985 (ISSN) Johari, N ; Madaah Hosseini, H. R ; Taromi, N ; Arasteh, S ; Kazemnejad, S ; Samadi Kuchaksaraei, A ; Sharif University of Technology
    Springer Berlin Heidelberg  2018
    Abstract
    Biodegradable polymer/bioceramic nanocomposites are osteoconductive and can accelerate healing of bone tissue. In this research, silk fibroin (SF)/titanium dioxide (TiO2) nanocomposites were synthesized using different concentrations of TiO2 nanoparticles (0, 5, 10, 15 and 20 wt%). The SF/TiO2 nanocomposites were studied in terms of bioactivity and biocompatibility. The in vitro assessment of osteoblasts compatibility indicated that SF inclusion rendered nanocomposite biocompatible whereas presence of TiO2 nanoparticles allowed the cells to adhere and grow on nanocomposite surface and enhanced the bioactivity of the composite. © 2017, Taiwanese Society of Biomedical Engineering  

    Enhancement mitochondrial apoptosis in breast cancer cells by paclitaxel-triphenylphosphonium conjugate in DNA aptamer modified nanoparticles

    , Article Journal of Drug Delivery Science and Technology ; Volume 54 , 2019 ; 17732247 (ISSN) Esfandyari Manesh, M ; Mohammadi, A ; Atyabi, F ; Ebrahimi, S. M ; Shahmoradi, E ; Amini, M ; Mirzaie, Z. H ; Ghahremani, M. H ; Dinarvand, R ; Sharif University of Technology
    Editions de Sante  2019
    Abstract
    Mitochondria is a major regulator of inducing tumor apoptosis and it is as a prime target for chemotherapy. Anticancers need to access specific tumor cells and also pass through different barriers such as outer and inner membranes of mitochondria. Targeted accumulation of paclitaxel (PTX) within the mitochondria was achieved by direct conjugation of PTX with triphenylphosphonium (TPP) as a mitochondrial membrane-permeable cation. PTX-TPP prodrug was synthesized by pH-sensitive ester bond between the hydroxyl function of PTX and the carboxylic function of TPP. This ester bond is only cleaved by the mitochondrial aldehyde dehydrogenase. Prodrug was loaded in the albumin nanoparticles by... 

    Poly(glycidyl methacrylate)-coated magnetic graphene oxide as a highly efficient nanocarrier: Preparation, characterization, and targeted DOX delivery

    , Article New Journal of Chemistry ; Volume 43, Issue 47 , 2019 , Pages 18647-18656 ; 11440546 (ISSN) Pourjavadi, A ; Kohestanian, M ; Yaghoubi, M ; Sharif University of Technology
    Royal Society of Chemistry  2019
    Abstract
    Herein, we report the preparation of novel magnetic graphene oxide (GO) grafted with brush polymer via surface-initiated reversible addition-fragmentation chain transfer (SI-RAFT) polymerization and its application as a nanocarrier for magnetic- and pH-triggered delivery of doxorubicin anticancer drug. The RAFT agent, DDMAT, was firstly attached to the surface of magnetic GO nanosheets. The DDMAT-functionalized magnetic GO nanosheets were then used to polymerize glycidyl methacrylate (GMA) using an SI-RAFT method. Afterwards, the epoxy rings of the PGMA chains were opened with hydrazine (N2H4) moieties. The resulting nanocomposite was used as a drug carrier for doxorubicin (DOX) as an... 

    Poly(glycidyl methacrylate)-coated magnetic graphene oxide as a highly efficient nanocarrier: Preparation, characterization, and targeted DOX delivery

    , Article New Journal of Chemistry ; Volume 43, Issue 47 , 2019 , Pages 18647-18656 ; 11440546 (ISSN) Pourjavadi, A ; Kohestanian, M ; Yaghoubi, M ; Sharif University of Technology
    Royal Society of Chemistry  2019
    Abstract
    Herein, we report the preparation of novel magnetic graphene oxide (GO) grafted with brush polymer via surface-initiated reversible addition-fragmentation chain transfer (SI-RAFT) polymerization and its application as a nanocarrier for magnetic- and pH-triggered delivery of doxorubicin anticancer drug. The RAFT agent, DDMAT, was firstly attached to the surface of magnetic GO nanosheets. The DDMAT-functionalized magnetic GO nanosheets were then used to polymerize glycidyl methacrylate (GMA) using an SI-RAFT method. Afterwards, the epoxy rings of the PGMA chains were opened with hydrazine (N2H4) moieties. The resulting nanocomposite was used as a drug carrier for doxorubicin (DOX) as an... 

    Niosomal delivery of simvastatin to MDA-MB-231 cancer cells

    , Article Drug Development and Industrial Pharmacy ; Volume 46, Issue 9 , 2020 , Pages 1535-1549 Akbarzadeh, I ; Saremi Poor, A ; Yaghmaei, S ; Norouzian, D ; Noorbazargan, H ; Saffar, S ; Ahangari Cohan, R ; Bakhshandeh, H ; Sharif University of Technology
    Taylor and Francis Ltd  2020
    Abstract
    Objective: The objective of this study was to use nano-niosomal formulations to deliver simvastatin as a poor-water soluble drug into breast cancer cells. Significance: Our study focused on the problem associated with poor water-soluble drugs which have significant biological activity in vivo. Methods: Different niosomal formulations of simvastatin were prepared and characterized in terms of morphology, size, encapsulation efficiency (EE), and release kinetic. Antiproliferative activity and the mechanism were assessed by quantitative real-time PCR and flow cytometry. Moreover, confocal microscopy was employed to analyze the cell uptake of simvastatin loaded niosomes to the cancerous cells.... 

    Nano mesoporous silica for cancer treatment: ROS-responsive and redox-responsive carriers

    , Article Journal of Drug Delivery Science and Technology ; Volume 57 , 2020 Bahrami, F ; Abdekhodaie, M. J ; Behroozi, F ; Mehrvar, M ; Sharif University of Technology
    Editions de Sante  2020
    Abstract
    Reactive oxygen species ROS and redox agents are two features of cancer medium, which could be used through responsive drug delivery systems for cancer treatment. Furthermore, mesoporous silica nanoparticles (MSNs) have special characteristics to use them in ROS-responsive and redox-responsive carriers. To shed light on this issue, we propose two drug delivery systems: 1) responsive to hydrogen peroxide (a ROS component) and 2) responsive to dithiothreitol (a redox agent). The proposed carriers are composed of 4 parts: MSNs, responsive agent (selenocystine for ROS-responsive and dithiodipropionic for the redox-responsive carrier), hyaluronic acid as the coating and targeting agent, and the... 

    Synthesis of magnesium-based Janus micromotors capable of magnetic navigation and antibiotic drug incorporation

    , Article New Journal of Chemistry ; Volume 44, Issue 17 , 2020 , Pages 6947-6957 Paryab, A ; Madaah Hosseini, H. R ; Abedini, F ; Dabbagh, A ; Sharif University of Technology
    Royal Society of Chemistry  2020
    Abstract
    In the present study, bubble-driven magnesium-based micromotors were fabricated through a shading method, and the potential of magnetic guidance of magnesium-based Janus micro/nanomotors through functionalization with superparamagnetic iron oxide nanoparticles (SPIONs) was investigated for the first time. SPIONs had physical electrostatic attraction with the positively charged magnesium spheres due to negative charges on their surfaces. It was also found that upon applying a field gradient, the micromotors’ velocity increased by 13% unlike other magnetically navigated spherical magnesium-based micromotors which only show a change in direction. In this work the cytotoxicity of the moving... 

    Can the body slope of interference screw affect initial stability of reconstructed anterior cruciate ligament?: An in-vitro investigation

    , Article BMC Musculoskeletal Disorders ; Volume 22, Issue 1 , 2021 ; 14712474 (ISSN) Daneshvarhashjin, N ; Chizari, M ; Mortazavi, J ; Rouhi, G ; Sharif University of Technology
    BioMed Central Ltd  2021
    Abstract
    Background: Superior biomechanical performance of tapered interference screws, compared with non-tapered screws, with reference to the anterior cruciate ligament (ACL) reconstruction process, has been reported in the literature. However, the effect of tapered interference screw’s body slope on the initial stability of ACL is poorly understood. Thus, the main goal of this study was to investigate the effect of the interference screw’s body slope on the initial stability of the reconstructed ACL. Methods: Based on the best screw-bone tunnel diameter ratios in non-tapered screws, two different tapered interference screws were designed and fabricated. The diameters of both screws were equal to...