• Macromolecular Research
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• v.16 no.4
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• pp.345-352
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• 2008

Poly(lactic-co-glycolic acid) (PLGA) tubes (5 mm in diameter) were fabricated using an electro spinning method and used as a scaffold for artificial blood vessels through the hybridization of smooth muscle cells (SMCs) and endothelial cells (ECs) differentiated from canine bone marrow under previously reported conditions. The potential clinical applications of these artificial blood vessels were investigated using a canine model. From the results, the tubular-type PLGA scaffolds for artificial blood vessels showed good mechanical strength, and the dual-layered blood vessels showed acceptable hybridization behavior with ECs and SMCs. The artificial blood vessels were implanted and substituted for an artery in an adult dog over a 3-week period. The hybridized blood vessels showed neointimal formation with good patency. However, the control vessel (unhybridized vessel) was occluded during the early stages of implantation. These results suggest a shortcut for the development of small diameter, tubular-type, nanofiber blood vessels using a biodegradable material (PLGA).

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.45.1-45.1
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• 2010

In this experiment, artificial blood vessel was fabricated from electro-spun PU/PCL. To assist with endothelial growth, PU/PCL surface was coated with the RGD peptide. To prevent a clot of blood, anti-thrombus agent was loaded to the fibrous mat and values were reflected through FT-IR data. In vitro study, SEM and MTT data showed that the component was of excellent biocompatibility and cell proliferation. In in vivo study, the artificial blood vessel was implanted in a dog's artery. The results of the CT scan, ultrasound and H&E staining showed that artificial blood vessel was excellent for artery replacement applications.

• Journal of the Korean Society of Visualization
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• v.14 no.1
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• pp.33-39
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• 2016

Radio-cephalic arteriovenous fistula(RC-AVF) is the most recommended operation of achieving access for hemodialysis. However, it has high rates of early failure depending on the many haemodynamic conditions. To increase RC-AVF patency rate, many researches were performed by in-vitro experiment via artificial vessel and blood analogue fluid, and there were conflicting opinions about whether the non-Newtonian properties of blood have an influence on the flow in large arteries. To investigate the influence of viscoelasticity of blood within the RC-AVF, we fabricated three dimensional artificial RC-AVF and two kinds of blood analogue fluid. The velocity field of two fluids within the vessel were measured by micro-particle velocimetry(m-PIV) and compared with each other. The velocity profiles of both fluids for systolic phase were matched well while those for diastolic phase did not correspond. Therefore, it is desired to use non-newtonian fluid for in-vitro experiment of RC-AVF.

• Journal of Sensor Science and Technology
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• v.16 no.1
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• pp.44-51
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• 2007

A hybridized simulator for generating blood pressure waveform is proposed to study the remedy and/or evaluation of the conventional sphygmomanometer utilizing the oscillometric method which is widely applied. The blood pressure of a flowing fluid was controlled for the blood vessel's condition caused by a rhythmical and periodical contraction/relaxation because of the special excitatory and conductive system of the heart. In this study, a hybridized controller composed of the PI feedback controller and the feedforward controller. The inverse dynamics function is proposed to operating the control valve while the pressure is applied in an oil pressure tank. The proposed hybrid simulator reproducing the blood pressure waveform in an artificial blood vessel has kept the control performance consistent over all range. Based on these results, the proposed simulators could be applied to the development and compensation of the non invasive sphygmomanometer type as well as to study the characteristics of the blood pressure and blood vessel.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.15 no.1
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• pp.55-66
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• 2011

Objectives: The purpose of this study is to review the simulator for cardiovascular system. Methods & Results: Simulators were classified according to the structure and function of cardiovascular system. Heart and blood vessel were selected as the represent of structure. Blood pressure and blood flow were chose as the functional index. With the view points of four keywords, four kinds of simulators were selected: artificial heart, pressure simulator, flow simulator, and pulse simulator. Conclusions: This paper discussed the state of the art of research and development of the selected four kinds of simulators.

• Korean Journal of Artificial Intelligence
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• v.3 no.1
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• pp.4-6
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• 2015

These days, citizens have made change of food life to take Western style food and to suffer from diabetes because of excessive nutrition taking, less exercise, stress and other environmental factors. They may suffer from diabetes because of genetic defect, surgery of pancreas, disinfection and medicine and others. One of ten Koreans may have symptom of diabetes to be popular. The diabetes that is a kind of metabolic disease has high blood sugar at disorder of hyper insulinism and/or defect of insulin action. Long time high blood sugar may produce chronic disease of kidney, eyes, nerve, heart and blood vessel and others. The purpose of health care of diabetes patient was to reach target blood sugar by diet, physical exercise and medicine and to prevent and delay complication. Diabetes patient shall control blood sugar to keep healthy. The blood sugar control requires time and effort, and all of the patients are difficult to make effort and to spend time. You can control blood sugar by the application. The application allows patients to control blood sugar and to save time and efforts and to make small sized input and automation of remaining area. The service was limited to blood sugar graph, and user carries smart phone to conduct test and to have difficulty. Further study needs to solve the problems and to investigate blood sugar testing not carrying smart phone and to make application of easy control of blood sugar.

• Korean Journal of Artificial Intelligence
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• v.4 no.1
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• pp.4-7
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• 2016

These days, citizens have made change of food life to take Western style food and to suffer from diabetes because of excessive nutrition taking, less exercise, stress and other environmental factors. They may suffer from diabetes because of genetic defect, surgery of pancreas, disinfection and medicine and others. One of ten Koreans may have symptom of diabetes to be popular. The diabetes that is a kind of metabolic disease has high blood sugar at disorder of hyper insulinism and/or defect of insulin action. Long time high blood sugar may produce chronic disease of kidney, eyes, nerve, heart and blood vessel and others. The purpose of health care of diabetes patient was to reach target blood sugar by diet, physical exercise and medicine and to prevent and delay complication. Diabetes patient shall control blood sugar to keep healthy. The blood sugar control requires time and effort, and all of the patients are difficult to make effort and to spend time. You can control blood sugar by the application. The application allows patients to control blood sugar and to save time and efforts and to make small sized input and automation of remaining area. The service was limited to blood sugar graph, and user carries smart phone to conduct test and to have difficulty. Further study needs to solve the problems and to investigate blood sugar testing not carrying smart phone and to make application of easy control of blood sugar.

• Journal of Chest Surgery
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• v.27 no.11
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• pp.948-952
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• 1994

Superior mesenteric artery aneurysm is the third most common lesion and comprises approximately 5.5 % of all visceral artery aneurysms. The first successful repair was performed by DeBakey and Cooley in 1949. Since then, more than 100 cases have been reported. Fifty to sixty percent of these aneurysms are mycotic in origin. Other less frequent causes include arteriosclerosis, trauma, and medial degeneration. The operations are bypass with autologous tissue or with artificial vascular graft and aneurysmorrhaphy. We have experienced a case of superior mesenteric artery aneurysm which had undergone aneurysmectomy and artificial graft interposition. This is the first domestic case which was successful surgical repaired.

• Polymer(Korea)
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• v.37 no.4
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• pp.411-419
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• 2013

Various biomaterials have been widely used for biomedical applications, including bio-organs, medical devices, and clinical devices like vessel, blood pumps, artificial kidneys and hearts, even in contact with blood. The issue of blood compatibility has been studied intensively to prevent negative effects such as thrombosis due to the implanted devices. The use of lotus-leaf-like structured surfaces has been extended to an increasing number of applications such as contamination prevention and anticorrosion applications. Various methods such as template, sol-gel transition, layer-by-layer, and other methods, developed for the fabrication of lotus-leaf-like surfaces have been reported for major industrial applications. Recently, the non-wettable character of these surfaces has been shown to be useful for biomedical applications ranging from blood-vessel replacement to antibacterial surface treatment. In this review, we provide a summary of current and future research efforts and opportunities in the development and medical applications of lotus-leaf-like structure surfaces.

• Journal of Biomedical Engineering Research
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• v.24 no.2
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• pp.113-119
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• 2003

In this paper we introduced optimized deformed shape to prevent the blood vessel disease caused by the discord of deformed shape in the end-to-end anastomosis. This study considered the preliminary deformed shape induced by suture in the anastomosis of artery and PTFE, artificial blood vessel, with different diameters. Then we analyzed the final deformed shape of the anastomotic part under the systolic blood pressure. 120mmHg(16.0kPa). The final deformed shape of the anstomotic part was analyzed with respect to the change of initial diameter ratio(R$_{I}$) and the PTFE thickness. Equivalent and circumferential stresses induced by the systolic blood pressure in the anastomosis were also analyzed with respect to the initial diameter ratio(R$_{I}$). The results obtained were as follows : 1. Considering the preliminary deformed shape induced by suture and the systolic pressure in the anastomosis, not intimal hyperplasia, the optimal initial diameter ratio(R$_{I}$) was 1.073. 2. As the initial diameter ratio(R$_{I}$) became larger, higher equivalent and circumferential stresses were induced. And all the maximum stresses occurred on the side of PTFE 0.4mm apart from the anastomosis.