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    A hybrid scaffold of gelatin glycosaminoglycan matrix and fibrin as a carrier of human corneal fibroblast cells

    , Article Materials Science and Engineering C ; Volume 118 , 2021 ; 09284931 (ISSN) Hajian Foroushani, Z ; Mahdavi salimi, S ; Abdekhodaie, M. J ; Baradaran Rafii, A ; Tabatabei, M. R ; Mehrvar, M ; Sharif University of Technology
    Elsevier Ltd  2021
    A hybrid scaffold of gelatin-glycosaminoglycan matrix and fibrin (FGG) has been synthesized to improve the mechanical properties, degradation time and cell response of fibrin-like scaffolds. The FGG scaffold was fabricated by optimizing some properties of fibrin-only gel and gelatin-glycosaminoglycan (GG) scaffolds. Mechanical analysis of optimized fibrin-only gel showed the Young module and tensile strength of up to 72 and 121 KPa, respectively. Significantly, the nine-fold increase in the Young modulus and a seven-fold increase in tensile strength was observed when fibrin reinforced with GG scaffold. Additionally, the results demonstrated that the degradation time of fibrin was enhanced... 

    Theoretical and experimental broadband tissue-equivalent phantoms at microwave and millimetre-wave frequencies

    , Article Electronics Letters ; Vol. 50, issue. 8 , April , 2014 , p. 618-620 ; ISSN: 00135194 Aminzadeh, R ; Saviz, M ; Shishegar, A. A ; Sharif University of Technology
    Several phantoms have been fabricated for reflection measurements from human tissues in the range of 26.5-40 GHz. For the first time, a novel composition is introduced for fabrication of low-cost simple tissue-equivalent phantoms. The effective medium theory is applied to estimate the dielectric properties of phantoms consisting of polyethylene (PE) powder and the results are verified by dielectric properties measurement on the proposed phantoms. It is shown that mixing theory can estimate the dielectric properties of the PE-based phantoms with minimum error. Therefore, the amount of the ingredients can be estimated theoretically  

    Design and fabrication of a new multi-loop saddle coil for 1.5 T MRI

    , Article Review of Scientific Instruments ; Volume 90, Issue 11 , 2019 ; 00346748 (ISSN) Parsa, J ; Mohammadzadeh, M ; Sharif University of Technology
    American Institute of Physics Inc  2019
    Radiofrequency coils provide high-resolution magnetic resonance (MR) imaging of human tissues. A small RF coil produces MR images with a higher resolution compared to the commercial volume MR coils from mass limited samples. Signal to noise ratio (SNR) plays a key role in the optimal design of receiver radiofrequency coils. In this work, we present a three-loop saddle coil suitable for MR imaging of digits of the human body. The geometry of the introduced coil is optimized to achieve the highest SNR. The coil performance is evaluated through comparing the measured SNR maps of the optimal coil derived from MR images of a saline phantom with the corresponding measured SNR maps of a commercial... 

    Equity or equality? Which approach brings more satisfaction in a kidney-exchange chain?

    , Article Journal of Personalized Medicine ; Volume 11, Issue 12 , 2021 ; 20754426 (ISSN) Hosseinzadeh, A ; Najafi, M ; Cheungpasitporn, W ; Thongprayoon, C ; Fathi, M ; Sharif University of Technology
    MDPI  2021
    In United States (U.S.), government-funded organizations, such as NLDAC, reimburse travel and subsistence expenses incurred during living-organ donation process. However, in Iran, there is a non-governmental organization called Iranian Kidney Foundation (IKF) that funds the direct and indirect costs of donors through charitable donations and contributions from participants in the exchange program. In this article, for countries outside the U.S. that currently use an equality approach, we propose a potential new compensation-apportionment approach (equitable approach) for kidney-exchange chains and compare it with the currently available system (equality approach) in terms of the... 

    SAR thresholds for electromagnetic exposure using functional thermal dose limits

    , Article International Journal of Hyperthermia ; Volume 34, Issue 8 , 2018 , Pages 1248-1254 ; 02656736 (ISSN) Adibzadeh, F ; Paulides, M. M ; Van Rhoon, G. C ; Sharif University of Technology
    Taylor and Francis Ltd  2018
    Background and purpose: To protect against any potential adverse effects to human health from localised exposure to radio frequency (100 kHz–3 GHz) electromagnetic fields (RF EMF), international health organisations have defined basic restrictions on specific absorption rate (SAR) in tissues. These exposure restrictions incorporate safety factors which are generally conservative so that exposures that exceed the basic restrictions are not necessarily harmful. The magnitude of safety margin for various exposure scenarios is unknown. This shortcoming becomes more critical for medical applications where the safety guidelines are required to be relaxed. The purpose of this study was to quantify... 

    Disc size markedly influences concentration profiles of intravenously administered solutes in the intervertebral disc: A computational study on glucosamine as a model solute

    , Article European Spine Journal ; Vol. 23, issue. 4 , April , 2014 , p. 715-723 Motaghinasab, S ; Shirazi-Adl, A ; Parnianpour, M ; Urban, J. P. G ; Sharif University of Technology
    Purpose: Tests on animals of different species with large differences in intervertebral disc size are commonly used to investigate the therapeutic efficacy of intravenously injected solutes in the disc. We hypothesize that disc size markedly affects outcome. Methods: Here, using a small non-metabolized molecule, glucosamine (GL) as a model solute, we calculate the influence of disc size on transport of GL into rat, rabbit, dog and human discs for 10 h post intravenous-injection. We used transient finite element models and considered an identical GL supply for all animals. Results: Huge effects of disc size on GL concentration profiles were found. Post-injection GL concentration in the rat... 

    Classification of abnormalities in mammograms by new asymmetric fractal features

    , Article Biocybernetics and Biomedical Engineering ; Volume 36, Issue 1 , 2016 , Pages 56-65 ; 02085216 (ISSN) Beheshti, S. M. A ; Ahmadi Noubari, H ; Fatemizadeh, E ; Khalili, M ; Sharif University of Technology
    PWN-Polish Scientific Publishers  2016
    In this paper we use fractal method for detection and diagnosis of abnormalities in mammograms. We have used 168 images that were carefully selected by a radiologist and their abnormalities were also confirmed by biopsy. These images included asymmetric lesions, architectural distortion, normal tissue and mass lesion where in case of mass lesion they included circumscribed benign, ill-defined and spiculated malignant masses. At first, by using wavelet transform and piecewise linear coefficient mapping, image enhancement were done. Secondly detection of lesions was done by fractal method as a ROI. Since in investigation of breast cancer, it is important that fibroglandular tissues in both... 

    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
    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... 

    On the modeling of human intervertebral disc annulus fibrosus: Elastic, permanent deformation and failure responses

    , Article Journal of Biomechanics ; Volume 102 , 2020 Ghezelbash, F ; Shirazi Adl, A ; Baghani, M ; Eskandari, A. H ; Sharif University of Technology
    Elsevier Ltd  2020
    As a primary load-resisting component, annulus fibrosus (AF) maintains structural integrity of the entire intervertebral disc. Experiments have demonstrated that permanent deformation and damage take place in the tissue under mechanical loads. Development of an accurate model to capture the complex behaviour of AF tissue is hence crucial in disc model studies. We, therefore, aimed to develop a non-homogenous model to capture elastic, inelastic and failure responses of the AF tissue and the entire disc model under axial load. Our model estimations satisfactorily agreed with results of existing uniaxial (along fiber, circumferential and axial directions) and biaxial tissue-level tests. The... 

    Differences in muscle synergies between healthy subjects and transfemoral amputees during normal transient-state walking speed

    , Article Gait and Posture ; Volume 76 , February , 2020 , Pages 98-103 Mehryar, P ; Shourijeh, M. S ; Rezaeian, T ; Khandan, A. R ; Messenger, N ; O'Connor, R ; Farahmand, F ; Dehghani Sanij, A ; Sharif University of Technology
    Elsevier B. V  2020
    Background: Lower limb amputation is a major public health issue globally, and its prevalence is increasing significantly around the world. Previous studies on lower limb amputees showed analogous complexity implemented by the neurological system which does not depend on the level of amputation. Research question: What are the differences in muscle synergies between healthy subjects (HS) and transfemoral amputees (TFA) during self-selected normal transient-state walking speed? Methods: thirteen male HS and eleven male TFA participated in this study. Surface electromyography (sEMG) data were collected from HS dominant leg and TFA intact limb. Concatenated non-negative matrix factorization... 

    Expression of apoptosome-related genes in periodontitis

    , Article Gene Reports ; Volume 23 , 2021 ; 24520144 (ISSN) Gholami, L ; Badrlou, E ; Nazer, N ; Sadeghi, G ; Kiani Haftlang, M ; Mirzajani, S ; Shadnoush, M ; Sayad, A ; Ghafouri Fard, S ; Sharif University of Technology
    Elsevier Inc  2021
    Recent studies have provided clues for participation of apoptosis related genes in the development of periodontitis. We examined expression of four apoptosome related genes namely CPSF7, AGO2, WDR33 and HUR1 in the blood and tissues of patients with stage III-IV periodontitis compared with control blood/tissue samples. Expression of AGO2 was significantly higher in the blood specimens of individual having periodontitis compared with healthy persons (ratio of mean expression = 6.9, P value = 4.79E−02). However, when categorizing individuals based on their gender, none of comparisons yielded significant results. Expression of AGO2 was not different between tissue samples of patients and... 

    Altered expression of STAT genes in periodontitis

    , Article Human Antibodies ; Volume 29, Issue 3 , 2021 , Pages 209-216 ; 10932607 (ISSN) Gholami, L ; Movafagh, A ; Badrlou, E ; Nazer, N ; Yari, M ; Sadeghi, G ; Mirzajani, S ; Shadnoush, M ; Sayad, A ; Ghafouri Fard, S ; Sharif University of Technology
    IOS Press BV  2021
    Signal Transducer and Activator of Transcription (STAT) pathway is functionally located downstream of Janus kinases proteins and can integrate signals from diverse pathways, thus regulating several aspects of immune responses. Although contribution of STAT proteins in the pathogenesis of several inflammatory conditions has been confirmed, their role in the development of periodontitis has been less appraised. Thus, we assessed levels of STAT transcripts in the periodontal tissues and circulation of affected individuals compared with the corresponding controls. Expression of STAT1 was remarkably lower in tissues samples of patients compared with control tissues (Ratio of mean expression (RME)... 

    Screening of glypican-6 expression in benign, primary and metastatic colon cancers

    , Article Clinical Medicine Insights: Oncology ; Volume 15 , 2021 ; 11795549 (ISSN) Al Saraireh, Y. M ; Alshammari, F. O. F. O ; Youssef, A. M. M ; Al Sarayreh, S ; Al Sarayra, Y. M ; Aborajooh, E ; Al Shuneigat, J ; Alrawashdeh, H. M ; Sharif University of Technology
    SAGE Publications Ltd  2021
    Background: The development of colon cancer has been described as a multistep process of carcinogenesis. Understanding molecular and cellular changes underlying this process is required to determine potential biomarkers and therapeutic targets in colon cancers. Several molecular entities, including glypicans, are implicated in cancer development. Among these is glypican-6, which is overexpressed in a limited number of cancers. This study aims to characterise the glypican-6 expression in different types of colon cancer. Methods: Immunohistochemistry was used to characterise glypican-6 expression in a panel of archived formalin-fixed, paraffin-embedded colon tissue types. These types included... 

    Prediction of temperature distribution and volume of lesion during HIFU therapy

    , Article ITNG 2009 - 6th International Conference on Information Technology: New Generations, 27 April 2009 through 29 April 2009, Las Vegas, NV ; 2009 , Pages 1468-1473 ; 9780769535968 (ISBN) Heydari, M ; Jahed, M ; Sharif University of Technology
    Ultrasound hyperthermia is used to treat tumors in human tissue by heat. It is characterized by the application of high intensity focused ultrasound (HIFU), high local temperatures and short treating time of a few seconds. HIFU is a non-invasive treatment modality for a variety of cancers, including breast, prostate, kidney, liver, bone, uterus, and pancreatic cancers. Computer models have been used to determine tissue temperatures during ultrasound hyperthermia. In this work, we consider a liver tissue with a tumor at its center. We calculated temperature distribution in the presence a large blood vessel. We studied the effect of varying the exposure time (heating duration) and the diameter... 

    Findings of DTI-p maps in comparison with T 2 /T 2 -FLAIR to assess postoperative hyper-signal abnormal regions in patients with glioblastoma 08 Information and Computing Sciences 0801 Artificial Intelligence and Image Processing

    , Article Cancer Imaging ; Volume 18, Issue 1 , 2018 ; 14707330 (ISSN) Beigi, M ; Safari, M ; Ameri, A ; Shojaee Moghadam, M ; Arbabi, A ; Tabatabaeefar, M ; Salighehrad, H ; Sharif University of Technology
    BioMed Central Ltd  2018
    Purpose: The aim of this study was to compare diffusion tensor imaging (DTI) isotropic map (p-map) with current radiographically (T 2/T 2 -FLAIR) methods based on abnormal hyper-signal size and location of glioblastoma tumor using a semi-automatic approach. Materials and methods: Twenty-five patients with biopsy-proved diagnosis of glioblastoma participated in this study. T 2, T 2 -FLAIR images and diffusion tensor imaging (DTI) were acquired 1 week before radiotherapy. Hyper-signal regions on T 2, T 2 -FLAIR and DTI p-map were segmented by means of semi-automated segmentation. Manual segmentation was used as ground truth. Dice Scores (DS) were calculated for validation of semiautomatic... 

    In vitro co-culture of human skin keratinocytes and fibroblasts on a biocompatible and biodegradable scaffold

    , Article Iranian Biomedical Journal ; Volume 13, Issue 3 , 2009 , Pages 169-177 ; 1028852X (ISSN) Shariati, S. R. P ; Shokrgozar, M. A ; Vossoughi, M ; Eslamifar, A ; Sharif University of Technology
    Background: Extensive full-thickness burns require replacement of both epidermis and dermis. In designing skin replacements, the goal has been to re-create this model and make a product which has both essential components. Methods: In the present study, we developed procedures for establishing confluent, stratified layers of cultured human keratinocytes on the surface of modified collagen-chitosan scaffold that contains fibroblasts. The culture methods for propagation of keratinocytes and fibroblasts isolated from human neonatal foreskin were developed. The growth and proliferation of normal human keratinocytes were evaluated in serum-free (keratinocyte growth medium) and our modified... 

    Genome-wide DNA methylation profiling in ectopic and eutopic of endometrial tissues

    , Article Journal of Assisted Reproduction and Genetics ; Volume 36, Issue 8 , 2019 , Pages 1743-1752 ; 10580468 (ISSN) Barjaste, N ; Shahhoseini, M ; Afsharian, P ; Sharifi Zarchi, A ; Masoudi Nejad, A ; Sharif University of Technology
    Springer New York LLC  2019
    Purpose: Endometriosis is a gynecological disease that causes the uterine lining to appear in other organs outside the uterus. As DNA methylation has an important role in this disorder, its profiling can reveal new information to improve the diagnosis and treatment of endometriosis patients. Methods: We conducted a genome-wide methylation profiling of ectopic and eutopic endometrial tissues from women with and without endometriosis using Infinium Human Methylation 450K BeadChip arrays. DNA methylation samples were collected from nine ectopic and nine eutopic endometrial tissues of endometriosis and six endometrial tissues of healthy controls. Results: Correlation heatmaps and the principal... 

    Cytochrome 4Z1 expression is associated with unfavorable survival in triple-negative breast cancers

    , Article Breast Cancer: Targets and Therapy ; Volume 13 , 2021 , Pages 565-574 ; 11791314 (ISSN) Al Saraireh, Y. M ; Alshammari, F. O. F. O ; Youssef, A. M. M ; Al Tarawneh, F ; Al Sarayreh, S ; Almuhaisen, G. H ; Satari, A. O ; Al Shuneigat, J ; Alrawashdeh, H. M ; Sharif University of Technology
    Dove Medical Press Ltd  2021
    Purpose: Triple-negative breast cancer (TNBC) is characterized by high mortality rate, and its clinical management is difficult and complex. Therefore, there is a need for extensive efforts aimed at accelerating the discovery of novel therapies for TNBC. CYP4Z1 has been implicated in the development of breast cancer. The current study aimed at characterizing the expression of CYP4Z1 on TNBC. Materials and Methods: Using immunohistochemistry, CYP4Z1 expression was evaluated on 122 TNBC samples, four samples of breast cancers expressing ER, PR, and HER-2, and four samples of normal breast tissues. The association between the enzyme and various histopathological features and survival of... 

    Glypican-1 overexpression in different types of breast cancers

    , Article OncoTargets and Therapy ; Volume 14 , 2021 , Pages 4309-4318 ; 11786930 (ISSN) Alshammari, F. O. F. O ; Al Saraireh, Y. M ; Youssef, A. M. M ; Al Sarayra, Y. M ; Alrawashdeh, H. M ; Sharif University of Technology
    Dove Medical Press Ltd  2021
    Purpose: Treatment of metastatic breast cancer patients is challenging and remains a major underlying cause of female mortality. Understanding molecular alterations in tumor development is critical to identify novel biomarkers and targets for cancer diagnosis and therapy. One of the aberrant cancer expressions gaining recent research interest is glypican-1. Several studies reported strong glypican-1 expression in various types of human cancers. However, none of these investigated glypican-1 expression in a large cohort of breast cancer histopathological subtypes. Patients and Methods: Immunohistochemistry was used to assess glypican-1 expression in 220 breast cancer patients and its relation... 

    A comprehensive approach for the validation of lumbar spine finite element models investigating post-fusion adjacent segment effects

    , Article Journal of Biomechanics ; Volume 121 , 2021 ; 00219290 (ISSN) Azadi, A ; Arjmand, N ; Sharif University of Technology
    Elsevier Ltd  2021
    Spinal fusion surgery is usually followed by accelerated degenerative changes in the unfused segments above and below the treated segment(s), i.e., adjacent segment disease (ASD). While a number of risk factors for ASD have been suggested, its exact pathogenesis remains to be identified. Finite element (FE) models are indispensable tools to investigate mechanical effects of fusion surgeries on post-fusion changes in the adjacent segment kinematics and kinetics. Existing modeling studies validate only their intact FE model against in vitro data and subsequently simulate post-fusion in vivo conditions. The present study provides a novel approach for the comprehensive validation of a lumbar...