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    The effect of endurance training with cinnamon supplementation on plasma concentrations of liver enzymes (ALT,AST) in women with type II diabetes

    , Article Tehran University Medical Journal ; Volume 74, Issue 6 , 2016 , Pages 433-441 ; 16831764 (ISSN) Torabi, S ; Asad, M. R ; Tabrizi, A ; Sharif University of Technology
    Tehran University of Medical Sciences  2016
    Background: Diabetes is associated with many pathological changes and one of the most important consequences of the diabetes is hepatic injury. The present study was performed to investigate the effect of eight weeks endurance training with consumption of cinnamon supplementation on plasma concentrations of liver enzymes,alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in women with type II diabetes. Methods: In this quasi-experimental study,36 female volunteers with type II diabetes (age 52.72±2.64 years and body mass index 29.28±2.94 Kg/m2) were participated. The subjects were homogenized regarding their body mass index and then were divided randomly into four groups... 

    A mechanobiological mathematical model of liver metabolism

    , Article Biotechnology and Bioengineering ; Volume 117, Issue 9 , 5 June , 2020 , Pages 2861-2874 Nikmaneshi, M. R ; Firoozabadi, B ; Munn, L. L ; Sharif University of Technology
    John Wiley and Sons Inc  2020
    The liver plays a complex role in metabolism and detoxification, and better tools are needed to understand its function and to develop liver-targeted therapies. In this study, we establish a mechanobiological model of liver transport and hepatocyte biology to elucidate the metabolism of urea and albumin, the production/detoxification of ammonia, and consumption of oxygen and nutrients. Since hepatocellular shear stress (SS) can influence the enzymatic activities of liver, the effect of SS on the urea and albumin synthesis are empirically modeled through the mechanotransduction mechanisms. The results demonstrate that the rheology and dynamics of the sinusoid flow can significantly affect... 

    Theoretical and Experimental Simulation of Hepatic Cells and their Functionalities On-a-chip

    , Ph.D. Dissertation Sharif University of Technology Sharifi, Fatemeh (Author) ; Firoozabadi, Bahar (Supervisor) ; Firoozbakhsh, Keikhosrow (Supervisor)
    Liver is the largest internal organ of the human body which serves many vital functionalities. Recently, liver-on-a-chip systems have been used to model some of the vital liver specific-functions and to investigate its related diseases. The purpose of the present study was simulation of some of these liver specific functionalities on-a-chip and using the obtained results in predicting hepatocellular functionalities i.e. production of some metabolites and modeling some of the liver-related diseases which have been done numerically and experimentally. Numerical simulations have been developed in two-dimensional and three-dimensional forms. In the 2D simulation, the governing equations i.e.... 

    Numerical Modeling of Treatment of Liver Tissue Cancer by Using High Intensity Focused Ultrasound (Hifu)

    , Ph.D. Dissertation Sharif University of Technology Mohammadpour Ghadikolaie, Maryam (Author) ; Firoozabadi, Bahar (Supervisor)
    In recent years, the incidence rate of liver cancer has increased sharply and nowadays liver cancer is known as the second leading cause of cancer death in the world. Surgical resection is usually used to treat malignant hepatic tumors. However, in some cases, surgical resection is not possible because of some reasons, such as tumor size and location. In these cases, other minimally invasive ablation methods such as radio-frequency ablation, microwave ablation, and high intensity focused ultrasound (HIFU) can be used. HIFU has some advantages such as noninvasiveness, high penetration depth, and low cost in comparison to the other ablation techniques such as radiofrequency ablation. In HIFU... 

    High intensity focused ultrasound (HIFU) ablation of porous liver: numerical analysis of heat transfer and hemodynamics

    , Article Applied Thermal Engineering ; Volume 170 , April , 2020 Mohammadpour, M ; Firoozabadi, B ; Sharif University of Technology
    Elsevier Ltd  2020
    In the present study, the influence of the liver vascular bed on heat transfer in a tumor located close to the hepatic artery and exposed to high intensity focused ultrasound (HIFU), is studied numerically. For this purpose, an acoustics-thermal-fluid coupling model based on the porous media theory under the local thermal non-equilibrium assumption is used to calculate the temperature field in the tumor, porous liver, and the hepatic artery. Different generations of the liver vasculature including arterial branches, terminal arterial branches, terminal veins and venous branches are examined at different porosities (the volume fraction of the vasculature). It is found that the liver... 

    Classification of normal and diseased liver shapes based on spherical harmonics coefficients

    , Article Journal of Medical Systems ; Vol. 38, issue. 5 , April , 2014 ; ISSN: 01485598 Mofrad, F. B ; Zoroofi, R. A ; Tehrani-Fard, A. A ; Akhlaghpoor, S ; Sato, Y ; Sharif University of Technology
    Liver-shape analysis and quantification is still an open research subject. Quantitative assessment of the liver is of clinical importance in various procedures such as diagnosis, treatment planning, and monitoring. Liver-shape classification is of clinical importance for corresponding intra-subject and inter-subject studies. In this research, we propose a novel technique for the liver-shape classification based on Spherical Harmonics (SH) coefficients. The proposed liver-shape classification algorithm consists of the following steps: (a) Preprocessing, including mesh generation and simplification, point-set matching, and surface to template alignment; (b) Liver-shape parameterization,... 

    Numerical study of the effect of vascular bed on heat transfer during high intensity focused ultrasound (HIFU) ablation of the liver tumor

    , Article Journal of Thermal Biology ; Volume 86 , 2019 ; 03064565 (ISSN) Mohammadpour, M ; Firoozabadi, B ; Sharif University of Technology
    Elsevier Ltd  2019
    In this study, the influence of vascular bed comprising terminal arterial branches on heat transfer in a liver tumor exposed to high intensity focused ultrasound (HIFU) is studied numerically. Also, the effect of vascular density on temperature distribution is investigated. A coupled set of acoustics, thermal, and fluid models is used to calculate the temperature distribution in the liver. The numerical model is established based on the Westervelt and bioheat equations along with the Navier-Stokes equations. Moreover, the acoustic streaming effect is included with Newtonian and non-Newtonian flow assumptions. It is found that in a vascular bed comprising terminal arterial branches, the... 

    Liver Segmentation in CT Images

    , M.Sc. Thesis Sharif University of Technology Babagholami Mohammadabadi, Behnam (Author) ; Manzouri, Mohammad Taghi (Supervisor)
    Image segmentation has a huge amount of applications in machine vision, target detection, medical image processing, etc. In many medical researches such as Organ and Gland Volume Specification, Analysis of Anatomical Structures and Multimodal Image Registration, Organ
    Segmentation is the first step of preprocessing.Since detection of diseases out of medical images depends on organ segmentation results,the segmentation process is done by experts which has a lot of disadvantages such as high time computation, high cost, etc. Hence, designing algorithms that can segment images with high accuracy and need minimum user interaction are desirable. So, in this thesis, a new
    knowledge based... 

    Numerical modeling of ureagenesis in a microfluidic channel mimicking a liver lobule

    , Article 2015 22nd Iranian Conference on Biomedical Engineering, ICBME 2015, 25 November 2015 through 28 November 2015 ; 2015 , Pages 54-59 ; 9781467393515 (ISBN) Sharifi, F ; Firoozabadi, B ; Saidi, M. S ; Firoozbakhsh, K ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2015
    Ammonia detoxification is one of the main functions of the liver results in production of urea. In this study ammonia elimination and urea production was simulated in a microchannel mimicking the hepatic porto central axis. Navier- Stockes equations along with convection equations were solved for the related species in the entire domain. Since the Reynolds number was small (~1) the fluid flow regime was laminar. Urea cycle was modeled regarding its four main enzymes. Twelve rate equations were also solved in order to obtain the concentration of each metabolites participating in urea cycle. Concentration of the urea reached its maximum ca. 1.2e-5 M at the end of the channel which is in good... 

    Design and implementation of series elastic actuators for a haptic laparoscopic device

    , Article Proceedings of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society: Engineering the Future of Biomedicine, EMBC 2009, 2 September 2009 through 6 September 2009, Minneapolis, MN ; 2009 , Pages 6054-6057 ; 9781424432967 (ISBN) Basafa, E ; Sheikholeslami, M ; Mirbagheri, A ; Farahmand, F ; Vossoughi, G. R ; Sharif University of Technology
    The design of a laparoscopic haptic device based on a 4-DOFs mechanism and Series Elastic Actuators (SEA) is described and the results of the theoretical and experimental examinations are presented. With a sufficient bandwidth and low impedance, the system provided a stable interaction with soft tissues, e.g., human liver, in virtual environments. ©2009 IEEE  

    Tool-tissue force estimation in laparoscopic surgery using geometric features

    , Article Studies in Health Technology and Informatics ; Volume 184 , 2013 , Pages 225-229 ; 09269630 (ISSN) Kohani, M ; Behzadipour, S ; Farahmand, F ; Sharif University of Technology
    IOS Press  2013
    This paper introduces three geometric features, from deformed shape of a soft tissue, which demonstrate good correlation with probing force and maximum local stress. Using FEM simulation, 2D and 3D model of an in vivo porcine liver was built for different probing tasks. Maximum deformation angle, maximum deformation depth and width of displacement constraint of the reconstructed shape of the deformed body were calculated. Two neural networks were trained from these features and the calculated interaction forces. The features are shown to have high potential to provide force estimation either for haptic devices or to assess the damage to the tissue in large deformations of up to 40%  

    3D calculation of absorbed dose for 131I-targeted radiotherapy: A monte carlo study

    , Article Radiation Protection Dosimetry ; Volume 150, Issue 3 , October , 2012 , Pages 298-305 ; 01448420 (ISSN) Saeedzadeh, E ; Sarkar, S ; Abbaspour Tehrani Fard, A ; Ay, M. R ; Khosravi, H. R ; Loudos, G ; Sharif University of Technology
    Various methods, such as those developed by the Medical Internal Radiation Dosimetry (MIRD) Committee of the Society of Nuclear Medicine or employing dose point kernels, have been applied to the radiation dosimetry of 131I radionuclide therapy. However, studies have not shown a strong relationship between tumour absorbed dose and its overall therapeutic response, probably due in part to inaccuracies in activity and dose estimation. In the current study, the GATE Monte Carlo computer code was used to facilitate voxel-level radiation dosimetry for organ activities measured in an . 131I-treated thyroid cancer patient. This approach allows incorporation of the size, shape and composition of... 

    Evaluation of liver shape approximation and characterization

    , Article IIH-MSP 2009 - 2009 5th International Conference on Intelligent Information Hiding and Multimedia Signal Processing, Kyoto, 12 September 2009 through 14 September 2009 ; 2009 , Pages 1297-1300 ; 9780769537627 (ISBN) Babapour Mofrad, F ; Aghaeizadeh Zoroofi , R ; Chen, Y. W ; Abbaspour Tehrani Fard, A ; Sato, Y ; Furukawa, A ; K.U.A.S.; RITSUMEIKAN; IEEE Computational Intelligence Society ; Sharif University of Technology
    A computational framework is presented for 3-D liver shape approximation and characterization in order to determine the accuracy of shape reconstruction via Spherical Harmonics expansion. Spherical Harmonics is a powerful mathematical tool for expanding the shape. But in medical domain, livers have very variation geometry, in shape, size, and volume. In this regards, we evaluated and optimized the Spherical Harmonics to create 3-D parametric surface of the liver from Computed Tomography (CT) imaging system which may useful for Shape modeling, surface representation, physical measurement of objects and mathematical model. We select randomly 5 livers from more 100 dataset. Mean Hausdorff... 

    Heat Transfer Modeling of Ultrasounic Hyperthermia

    , M.Sc. Thesis Sharif University of Technology Heydari, Mohsen (Author) ; Jahed, Mehran (Supervisor)
    Ultrasound hyperthermia is a commonly used noninvasive approach to destroy cancer tumors. High Intensity Focused Ultrasound (HIFU) is a technique based on hyperthermia. It creates short and local elevations of temperature at a focus site within the tissue of interest. The main goal of HIFU is to maintain the temperature between 50 and 100 °C for a few seconds (typically less than 10 s), in order to cause tissue necrosis. In order to predict the effects of hyperthermia, accurate and effective modeling is needed. This study considers a 3D simulation of the hyperthermia based on HIFU method in the liver tissue. Temperature distribution and lesion volume changes, with a temperature of above... 

    A novel wavelet based multi-scale statistical shape model-analysis for the liver application: Segmentation and classification

    , Article Current Medical Imaging Reviews ; Volume 6, Issue 3 , 2010 , Pages 145-155 ; 15734056 (ISSN) Babapour Mofrad, F ; Abbaspour Tehrani Fard, A ; Aghaeizadeh Zoroofi, R ; Akhlaghpoor, S ; Chen, Y. W ; Sharif University of Technology
    Several methods have been proposed to construct Statistical Shape Model (SSM) to aim image analysis using computer in field Computer Aided Diagnosis (CAD), Computer Assisted Surgery (CAS), and other medical applications by providing a prior knowledge. The major challenge for liver shape model is a high variation in geometry such as size, shape and volume between livers. In this paper, we have presented a new technique for the automatic Multi-Scale Statistical Shape Model (MS-SSM) of three-dimensional (3-D) liver from volumetric segmented images data. The procedure included both building of Spherical Harmonics shape description and the Wavelet transform. Principal Component Analysis (PCA) was... 

    Statistical construction of a Japanese male liver phantom for internal radionuclide dosimetry

    , Article Radiation Protection Dosimetry ; Volume 141, Issue 2 , 2010 , Pages 140-148 ; 01448420 (ISSN) Babapour Mofrad, F ; Aghaeizadeh Zoroofi, R ; Abbaspour Tehrani Fard, A ; Akhlaghpoor, S ; Hori, M ; Chen, Y. W ; Sato, Y ; Sharif University of Technology
    A computational framework is presented, based on statistical shape modelling, for construction of race-specific organ models for internal radionuclide dosimetry and other nuclear-medicine applications. This approach was applied to the construction of a Japanese liver phantom, using the liver of the digital Zubal phantom as the template and 35 liver computed tomography (CT) scans of male Japanese individuals as a training set. The first step was the automated object-space registration (to align all the liver surfaces in one orientation), using a coherent-point-drift maximum-likelihood alignment algorithm, of each CT scan-derived manually contoured liver surface and the template Zubal liver... 

    Modeling, simulation, and optimal initiation planning for needle insertion into the liver

    , Article Journal of Biomechanical Engineering ; Volume 132, Issue 4 , 2010 ; 01480731 (ISSN) Sharifi Sedeh, R ; Ahmadian, M. T ; Janabi Sharifi, F ; Sharif University of Technology
    Needle insertion simulation and planning systems (SPSs) will play an important role in diminishing inappropriate insertions into soft tissues and resultant complications. Difficulties in SPS development are due in large part to the computational requirements of the extensive calculations in finite element (FE) models of tissue. For clinical feasibility, the computational speed of SPSs must be improved. At the same time, a realistic model of tissue properties that reflects large and velocity-dependent deformations must be employed. The purpose of this study is to address the aforementioned difficulties by presenting a cost-effective SPS platform for needle insertions into the liver. The study... 

    Numerical and experimental evaluation of high-intensity focused ultrasound-induced lesions in liver tissue ex vivo

    , Article Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine ; Volume 37, Issue 6 , 2018 , Pages 1481-1491 ; 15509613 (ISSN) Haddadi, S ; Ahmadian, M. T ; Sharif University of Technology
    OBJECTIVES: Recent advances in the field of acoustics and piezoelectric and ultrasound transducers have led to new approaches to the diagnosis and treatment of certain diseases. One method of treatment with ultrasonic waves is high-intensity focused ultrasound (HIFU) treatment, which is a thermal therapeutic method used to treat malignant tumors. Although a variety of treatment-planning strategies using ultrasonic waves have been investigated, little clinical success has been achieved. Computational modeling is a powerful tool for predicting device performance. METHODS: The heating induced by a concave transducer with operating powers of 85 and 135 W was studied, and the experimental results... 

    Evaluation of the effects of fullerene c60 nanoparticles on oxidative stress parameters in normal rats liver and brain

    , Article Journal of Advances in Medical and Biomedical Research ; Volume 27, Issue 124 , 2019 , Pages 8-15 ; 26766264 (ISSN) Namadr, F ; Bahrami, F ; Bahri, Z ; Ghanbari, B ; Elahi, S. A ; Mohammadi, M. T ; Sharif University of Technology
    Zanjan University of Medical Sciences and Health Services  2019
    Background & Objective: The potent antioxidant property of fullerene C60 nanoparticles and their derivatives has been demonstrated in a wide range of in vitro and in vivo studies. Hence, we examined the effects of fullerene C60 on the oxidative stress parameters in brain and liver of the rats in normal situation. Materials & Methods: The study was performed in two groups of Wistar rats (each group, n = 6); normal and fullerene-treated normal animals. Treated rats received fullerene via oral gavage at dose of 1 mg/kg/day for 60 days. At termination of the study, the oxidative stress parameters were determined in brain and liver tissues, including the contents of glutathione (GSH) and... 

    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...