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    The regulated market for kidneys in Iran

    , Article Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, 22 August 2011 through 23 August 2011 ; Volume 80 LNICST , August , 2012 , Pages 62-75 ; 18678211 (ISSN) ; 9783642309120 (ISBN) Fatemi, F ; Sharif University of Technology
    We study the kidney market in Iran. The most effective treatment for end-stage renal disease is a kidney transplant. While the supply of cadaveric kidneys is limited, the debate has been focused on the effects of the existence of a free market for human organs. Economists as well as medical and legal researchers are divided over the issue. Iran has a unique kidney market which has been in place for over 20 years, frequently reporting surprising success in reducing the waiting list for kidneys. This paper demonstrates how the Iranian system works  

    A Mathematical Model to Organize Transplants in a Kidney Exchange Program with Uncertain Failures

    , M.Sc. Thesis Sharif University of Technology Porbar, Gohar (Author) ; Najafi, Mehdi (Supervisor) ; Shadrokh, Shahram (Supervisor)
    Kidney transplants are vital for patients with end-stage kidney disease. Therefore, it is essential to allocate kidneys to patients efficiently. Kidney Exchange Programs allow patients with incompatible donors to exchange donors and receive a suitable kidney. In practice, these exchanges occur within cyclic or chain-like structures. Planned transplants may be canceled before the transplant takes place, for a variety of reasons. Failure of one transplant in a cycle or chain can result in the failure of all transplants in that cycle or chain, which can lead to drastic inefficiency in the exchange program.In this thesis, we study kidney exchange programs under uncertainty. We consider... 

    Exploring stakeholders and their requirements in the process of home hemodialysis: A literature review

    , Article Seminars in Dialysis ; 2021 ; 08940959 (ISSN) Khan, I ; Pintelon, L ; Martin, H ; Khan, R. A ; Sharif University of Technology
    John Wiley and Sons Inc  2021
    Providing home hemodialysis (HHD) therapy is a complex process that not only requires the use of a complex technology but also involves a diverse group of stakeholders, and each stakeholder has their requirements and may not share a common interest. Bringing them together will require the alignment of their interests. A process management perspective can help to accomplish the alignment of their interests. To align their interests, it is crucial to identify interest groups and understand their interests. The main objective of this paper is to identify the stakeholders and represents their interests as a list of requirements in the HHD process. An extensive literature review has been carried... 

    Development of an Automatic Produnction and Growth of Kidney Vascular Structure based on Graph Grammar Methods

    , M.Sc. Thesis Sharif University of Technology Fozooni, Ali (Author) ; Bozorgmehry Boozarjomehry, Ramin (Supervisor)
    The kidney is one of the most complicated organs in terms of structure and physiology, in part because it is highly vascularized. Previous investigations have focused on specific characteristics like length and diameter. There are a few methods like those which are based on image processing techniques, that have been focused on all features as a unique structure. The clear drawback of these approaches is inability to justify growth and changes. Lindenmayer system (L-system) is parallel rewriting method and a type of graph grammars. L-system can justify growth and all characteristic changes and adopt itself to them. Parametric rewriting rules incorporating within physiological laws of the... 

    Design, Fabrication and Analyses of an Ultrasonic Probe for Kidney Lithotripsy Device

    , M.Sc. Thesis Sharif University of Technology Amini, Naseh (Author) ; Ahmadian, Mohammad Taghi (Supervisor) ; Firoozbakhsh, Keykhosrow (Supervisor)
    Kidney stone disease is one of the diseases that a large number of people experience each year.A Common method for the treatment of kidney stone is the use of acoustic waves, which have attracted the attention of doctors in recent decades. Because of the different structure of kidney stones, the waves transmitted to break these stones are usually performed at different frequencies. Most kidney stones are calcium that can be broken down by using acoustic wave frequencies in the range of 40-20 KHz. Most available lithotripters for the treatment of percutaneous nephrolithotomy (PCNL) are two types: Pneumatic and piezoelectric lithotripters. The lithotripter in this thesis is a piezoelectric... 

    An Application of Mathematical Programming in Kidney Exchange Problem

    , M.Sc. Thesis Sharif University of Technology Talei, Alireza (Author) ; Eshghi, Kourosh (Supervisor)
    One of the most efficient techniques deployed for end-stage renal disease remedy is kidney transplantation, but in this case, we commonly encounter with the problem of gap between the demand of patients and supply of donors. In the majority of models has been proposed until now, either kidney exchange technique in a pool of incompatible pairs or kidney allocation system from deceased donors to waiting list is recommended. In this research, in order to enhance kidney transplantation plans, first, a hybrid conceptual model is proposed. Then, its mathematical model is discussed, in which some of the transplantations are selected from kidney allocation system before injecting to the pool of... 

    A Mathematical Model to Apportion the Cost of Kidney Purchasing in Domino-paired Donation

    , M.Sc. Thesis Sharif University of Technology Hosseinzadeh, Arian (Author) ; Najafi, Mehdi (Supervisor)
    The human body normally has two functioning kidneys, while only one of them is sufficient to have a healthy life. However, for those patients having no functioning kidney, transplantation is the most effective treatment. Although deceased donors have been usually used as the main source for kidney donation in many countries, there are several cases focusing on living kidney donation to compensate for the shortage in supply and to reduce the patient waiting time for treatment. Because of this potential, many studies have been conducted to optimize the non-clinical issues of kidney transplant waiting lists. Notwithstanding employing the financial incentives for living kidney donation is... 

    Queue Modeling of Patients in Waiting list of Kidney Transplantation

    , M.Sc. Thesis Sharif University of Technology Amini, Fatemeh (Author) ; Modarres Yazdi, Mohammad (Supervisor)
    As the number of patients waiting for receiving kidney transplantation increases all over the world, the average waiting time for a patient in queue rises too, and consequently, the rate of death goes beyond the accepted level. Also, unbalanced numbers of donors and patients with same blood type make the problem bolder. The aim of this research is to design a queuing model in which kidney could be transplanted from deceased donors to patients with different but compatible blood type (Cross-Transplantation) in order to make the average waiting time for patients with different blood type closer to each other. In other words, the transplant system is supposed to make a decision whether to... 

    A Data-Driven Optimization Methodology to Improve Unmatched Pairs Assignment in Kidney Exchange Problem

    , M.Sc. Thesis Sharif University of Technology Dadashi, Hossein (Author) ; Najafi, Mahdi (Supervisor) ; Rafiee, Majid (Supervisor)
    One of the most common and effective ways to treat end-stage renal disease is the use of kidney exchange techniques. However, the main problem with this treatment is the presence of many barriers to allocating kidney pairs to each other, which reduces the success of kidney transplants. Among different types of kidney transplantation methods, the present study utilizes kidney transplantation cycles to develop the allocation of unmatched pairs in kidney transplantation using a data-driven optimization technique. In this study, HLA patients were considered as simulated and also a two-objective model in the kidney exchange network was designed to maximize the probability of kidney... 

    Market of Kidney in Iran

    , M.Sc. Thesis Sharif University of Technology Didgar, Dadmehr (Author) ; Fatemi Ardestani, Farshad (Supervisor)
    In this study we developed an analytical model to delve into the behavior of participants in the market of kidney in Iran. We get health as a good which not only elevates the utility of any individual, it add more years to each individual longevity. We find out that ESRD patients who are in serious need of receiving a new kidney will never postpone buying kidney in case of having the price fixed in all periods.We found out that the waiting time in queue of receiving market is a u-shape function in which there is a minimum. We proved that the price making the queue minimum is definitely bigger than the market clearance market. Accordingly, despite all the unfair and immoral view toward... 

    Modeling the Kidney Market in Iran

    , M.Sc. Thesis Sharif University of Technology Naderi Tabar, Mohammad (Author) ; Fatemi Ardestani, Farshad (Supervisor)
    The purpose of this study is to model people's behavior on both sides of the kidney market. The healthy person decides to donate a live kidney (for a certain amount) on the supply side. On the demand side, the patient chooses between the two existing kidney queues, the living kidney and the cadaveric kidney, based on the individual's income and belief from the waiting time in each of the two queues. The sick person faces two critical risks in life: risk of death and kidney failure. To model these two risks, it is assumed that each person has a level of health that consists of two deterministic and stochastic parts. In this way, with a deterministic rate, a person's health level will decrease... 

    Three-dimensional simulation of urine concentrating mechanism in a functional unit of rat outer medulla. I. Model structure and base case results

    , Article Mathematical Biosciences ; Vol. 258 , 2014 , pp. 44-56 ; ISSN: 00255564 Sohrabi, S ; Saidi, M. S ; Saadatmand, M ; Banazadeh, M. H ; Firoozabadi, B ; Sharif University of Technology
    The urine formation and excretion system have long been of interest for mathematicians and physiologists to elucidate the obscurities within the process happens in renal tissue. In this study, a novel three-dimensional approach is utilized for modeling the urine concentrating mechanism in rat renal outer medulla which is essentially focused on demonstrating the significance of tubule's architecture revealed in anatomic studies and physiological literature. Since nephrons and vasculatures work interdependently through a highly structured arrangement in outer medulla which is dominated by vascular bundles, a detailed functional unit is proposed based on this specific configuration.... 

    3D simulation of solutes concentration in urinary concentration mechanism in rat renal medulla

    , Article Mathematical Biosciences ; Volume 308 , 2019 , Pages 59-69 ; 00255564 (ISSN) Mahdavi, S. S ; Abdekhodaie, M. J ; Farhadi, F ; Shafiee, M. A ; Sharif University of Technology
    Elsevier Inc  2019
    In this work, a mathematical model was developed to simulate the urinary concentration mechanism. A 3-D geometry was derived based on the detail physiological pictures of rat kidney. The approximate region of each tubule was obtained from the volume distribution of structures based on Walter Pfaller's monograph and Layton's region-based model. Mass and momentum balances were applied to solve for the change in solutes concentration and osmolality. The osmolality of short and long descending nephrons at the end of the outer medulla was obtained to be 530 mOsmol/kgH2O and 802 mOsmol/kgH2O, respectively, which were in acceptable agreement with experimental data. The fluid osmolality of the short... 

    Simulation, Design and fabrication of Kidney on a Chip

    , Ph.D. Dissertation Sharif University of Technology Kiyoumarsioskouei, Amir (Author) ; Saeedi, Mohammad Saeed (Supervisor) ; Firoozabadi, Bahar (Supervisor) ; Mosadegh, Bobak ($item.subfieldsMap.e)
    Renal diseases and consequently kidney failure is one of the important death factors around the world in recent years. It causes hundreds of thousands die every year and is in progress. Researchers believe that increasing chemical and nonchemical materials density in the blood which is the air pollution, use of tobacco and other parameters cause renal cells misfunction in urine filtration and regulation of blood pressure. The goal of this work is design and fabrication of a microfluidic device which provides different cell types to be cultured and imposed pressure. To do this, a high throughput microfluidic device is needed to mimic kidney biologically. Having such a device helps to analyze... 

    Urine Analysis by a Microfluidic Paper-Based Device for Renal Function Test

    , M.Sc. Thesis Sharif University of Technology Pourghanbari Marvast, Mohadeseh (Author) ; Saadatmand, Maryam (Supervisor)
    Chronic kidney disease is one of the silent diseases that progresses slowly, often without symptoms, and can eventually lead to kidney loss. Early detection of this disease can help diagnose it and prevent further problems. Urinary creatinine is an effective biomarker for early diagnosis of chronic kidney disease, but methods available in clinics are problematic for people living in disadvantaged areas because of the high cost and the need for 24-hour urine collection. Currently, paper-based microfluidic devices are being developed because they are easy to manufacture, inexpensive, the fluid is permeable by capillary force, and no additional equipment is needed. In this work, to fabricate a... 

    Preparation of Hemodialysis Membrane on the Basis of Polysulfone

    , M.Sc. Thesis Sharif University of Technology Sajjadi, Morteza (Author) ; Moosavi, Ali (Supervisor) ; Abd Khodaei, Mohammad Jafar (Supervisor)
    In Hemodialysis, membrane dialyser and commonly hollow fibers are used to treat patients who suffer from end stage renal failure. When blood flows into membrane, it loses uremic toxins such as urea and creatinine. On the other hand, some of the vital proteins of blood pass through the membrane or they are adsorbed on the membrane surface. The more hydrophilicity of the membrane, the less adsorption of proteins is. In this study, to achieve high hydrophilicity and low adsorption of proteins on the polysulfone membrane surface, the presence of hydrophilic nano-particles SBA-15 in membrane composition is investigated. The nano-particles with mass percentages 0.25%, 0.5 % and 1 % to one mass of... 

    Simulation of the Urinary Concentration Mechanism

    , M.Sc. Thesis Sharif University of Technology Mahdavi Salimi, Sharareh (Author) ; Abd Khodaei, Mohammad Jafar (Supervisor) ; Farhadi, Fathollah (Supervisor)
    The kidneys serve essential regulatory roles in the body which remove excess organic molecules from the blood and the removal of waste products of metabolism. They are essential in the urinary system. Urinary concentration mechanism has long been interested for mathematicians and physiologists to elucidate the obscurities within the process. In this study, a novel three-dimensional approach is used for simulating urine concentrating mechanism in rat renal medulla. The model equations are based on three spatial dimensions mass and momentum transports. Exact 3D geometry has been designed by using COMSOL Multiphysics software and results have been compared with the latest available data. In... 

    A noninvasive urine metabolome panel as potential biomarkers for diagnosis of t cell-mediated renal transplant rejection

    , Article OMICS A Journal of Integrative Biology ; Volume 24, Issue 3 , March , 2020 , Pages 140-147 Kalantari, S ; Chashmniam, S ; Nafar, M ; Samavat, S ; Rezaie, D ; Dalili, N ; Sharif University of Technology
    Mary Ann Liebert Inc  2020
    Acute T cell-mediated rejection (TCMR)is a major complication after renal transplantation. TCMR diagnosis is very challenging and currently depends on invasive renal biopsy and nonspecific markers such as serum creatinine. A noninvasive metabolomics panel could allow early diagnosis and improved accuracy and specificity. We report, in this study, on urine metabolome changes in renal transplant recipients diagnosed with TCMR, with a view to future metabolomics-based diagnostics in transplant medicine. We performed urine metabolomic analyses in three study groups: (1) 7 kidney transplant recipients with acute TCMR, (2) 15 kidney transplant recipients without rejection but with impaired kidney... 

    Simulation of Urine Concentrating Mechanism in Rat Kidney Inner Medulla

    , M.Sc. Thesis Sharif University of Technology Sanatkhani, Soroush (Author) ; Saeedi, Mohammad Saeed (Supervisor)
    Physicians use charts that are prepared by experiments on animals or humans to prescribe drug dosage for patients. This method requires much more time by the Ministry of Health to approve new drugs to be used in health-care centers. Furthermore،we have no sight on how a specific drug is going to be diffuse in our body. In order to predict the distribution of a drug or any minerals in the kidney we need to model it. The first step would be modeling the important species that influence the urine concentrating mechanism. Due to the complications in modeling that mechanism especially in the inner medulla zone، we hadn’t solid information regarding that area. It is about half a century that... 

    Modeling of Renal Autoregulation Systems

    , M.Sc. Thesis Sharif University of Technology Rajabtabar, Mohammad Javad (Author) ; Saeedi, Mohammad Saeed (Supervisor) ; Firoozbakhsh, Keikhosrow (Supervisor)
    The mathematical analysis of the kidney has always been considered due to its complex performance. It’s about two decades that mathematicians work on the mathematical modeling of this tissue. Since Glomerular filtration of blood in the kidney has been regarded by physiologists for many years, they can access only to the qualitative data. Mathematicians can solve this problem by numerical modeling. In this research, an engineering model is presented for the analysis of this capillary network by investigating in the different scientific fields such as, physiology, medicine, computer science and mathematics. There are two major renal autoregulatory mechanisms, the myogenic response and the...