• Title/Summary/Keyword: Vascular measurement

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A Simulation Study of Impedance Plethysmography for Diagnosing Deep Vein Thrombosis (Deep Vein Thrombosis 진단을 위한 Impedance Plethysmography의 시뮬레이션 연구)

  • Lee, Jeon;Lee, Kyoung-Joung
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.50 no.10
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    • pp.494-501
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    • 2001
  • In this study, the effects of vascular parameter changes and electrodes on VOP measurement based on IPG were simulated mathematically. For the evaluation of the effects of hemodynamic changes on VOP, a mathematical model, which consists of cardiovascular system model and venous occlusion model, was developed and the model solution representing the blood flow and pressure in measuring point was found by 2nd order Runge-Kutta method. And, with sensitivity coefficients obtained from finite element solution of electric field in measuring point, the effects of electrode system on measurement were evaluated. As increasing the resistance, the venous capacitance was not changed but the venous outflows were decreased and the decreased compliance reduced the venous capacitance. And, for several configurations of round electrodes and band electrodes, the sensitivity coefficients were computed using the electric field distribution along deep vein. In conclusion, the proposed mathematical cardiovascular model could be applied to the simulation study on the effects of hemodynamic parameters on DVT diagnosis with IPG. And, also the sensitivity coefficients could provide effective electrode configuration for exact measurement of VOP.

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Effect of Dietary Fat Sources and L-arginine Supplementation on Endothelial function and Lipid Metabolism in Streptozotocin-Induced Diabetic Rats (식이지방의 종류와 L-arginine 보충이 당뇨쥐의 ENdothelium 기능 및 체내 지질대사에 미치는 영향)

  • 장문정;김연중;김명환
    • Journal of Nutrition and Health
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    • v.35 no.1
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    • pp.5-14
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    • 2002
  • Alteration in the syntesis or enhanced inactivation of nitric oxide(NO) can induce impairment of endothelial cell function. Insulin dependent diabetes mellitus(IDDM) is characterized by impaired endothelial function and vascular disease. NO is produced through L-arginine pathway To elucidate the hypothesis that the decreased production on NO in IDDM reflects vascular damage and the NO production can be manipulated by either dietary fat(7% of kg diet) or the oral supplementation with L-arginine(2g/kg bw), plasma markers for vascular endothelial damage and plasma lipid profiles were measured in streptozotocin(STZ)-induced diabetic rats. Diabetic or normal Sprague-Dawley rats were fed 6 different experimental diets for 4 weeks(SO : soybean oil, SOA: soybean oil + L-arginine supplementation, BT : beef tallow, BTA_ beef tallow + L-arginine supplementation, OV olive oil, OVA : olive oil + L-arginine supplementation). Plasma glucose, total cholesterel, HDL-cholesterol, LDL-cholesterol and triglyceride were measured. Endothelial markers, plasma von Willebrand factor(vWf), thromboxane B$_2$, and 6-keto PGF1$\alpha$ of aorta were measured by ELISA. Plasma NO production was evaluated through the measurement of nitrite by EIA. Feeding saturated fatty acid(SFA, BT) increased relative liver size(RLS) in diabetic rats compared to either polyunsatunted fatty acid(PUFA, SO) or monounsaturated fatty acid(MUFA, OV) The supplementation of L-arginine inhibited the liver and kidney enlargement in olive oil find diabetic rats. Plasma glucose was lower in diabetic animal find the olive oil compared to fed beef tallow and the supplementation L-arginine decreased it in diabetic rats find beef tallow significantly(p < 0.05). Plasma TXB$_2$ levels were increased due to diabetes and the value of beef tallow group showed highest value. Plasma vWf concentration of beef tallow group was higher value in normal rats and was elevated more in diabetes. In diabetic groups, the vWf concentration of olive oil group was lower than beef tallow or soybean oil group. The supplementation of L-arginine in diabetic rats decreased plasma TXB$_2$ and vWf levels significantly(p < 0.05). NO production was higher in normal olive oil fed rats and was tend to be decreased in diabetic rats and the supplementation of L-arginine recovered to normal value(p < 0.05), Olive oil supplemented with L-arginine tended to lower plasma total cholesterol and LDL-cholesterol after 4 week treatment. These results suggest that generalized vascular endothelial changes based on plasma TXB$_2$and vWf occurs in diabetic rats. and olive oil with L-arginine supplementation contributes to a better control of the hyperglycemia, endothelial changes and hypercholesterolemia accompanying diabetes as compared with beef tallow or soy bean oil in this rat model.

Influence of the Aqua Exercise on Blood Component and Vascular Compliance of Mental Retardation Men (수중운동 참여가 정신지체장애인의 혈액성분 및 혈관탄성에 미치는 영향)

  • Kim, Won-Hyun;Kim, Seung-Suk;Park, Young-Woo
    • Journal of Digital Convergence
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    • v.11 no.6
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    • pp.235-244
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    • 2013
  • This research was performed to investigate the effects of participation in aqua exercise on blood composition and vascular compliance of mentally retarded persons. The targets of this research consisted of a control group of 12 people and an aqua exercise group of 12 people after selecting 24 mentally retarded males and aqua exercise group carried out an exercise program for 60 minutes per day and five days a week for 9 weeks. Weight, body fat percentage, blood composition and vascular compliance were measured in a preliminary inspection and the same items were measured in a post-inspection. The results of this measurement were as follows. Firstly, aqua exercise group showed a significant decrease in weight and body fat percentage (p<.05). Secondly, for blood composition, aqua exercise group showed a notable decrease in Total-Cholesterol, Triglyceride, and LDL-Cholesterol (p<.05) and a significant increase in HDL-Cholesterol (p<.05). Thirdly, aqua exercise group showed a notable increase in blood composition for both upper limbs and lower limbs (p<.05). Taken these results together, it was considered that a participation of mentally retarded persons in aqua exercise would prevent adult diseases and would have an affirmative influence on improvement of the quality of life.

Evaluation of Significance on the Brachial-ankle arterial pulse wave velocity And Cerebral Artery Vascular Stenosis (상완-발목 맥파 전달 속도와 뇌동맥 혈관 협착과의 유의성 평가)

  • Kim, Ji-Yul;Ye, Soo-Young
    • Journal of the Korean Society of Radiology
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    • v.13 no.6
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    • pp.873-878
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    • 2019
  • Cerebrovascular disease is one of the three major causes of death in Korea. Since these diseases are associated with atherosclerosis, the diagnosis of atherosclerotic factors should be presented. In this study, we evaluated the relationship between brachial-ankle arterial pulse wave velocity, cerebral artery vascular stenosis, blood pressure, obesity, and abdominal obesity by age group. The significance of cerebral artery stenosis and age group. The risk factors of atherosclerosis, such as blood pressure, obesity, and abdominal obesity, were significant in all age groups. When the pulse wave velocity of the brachial-ankle artery was increased, the cerebral artery stenosis was distributed in 57.3% of the total test subjects. If the arterial stiffness is suspected during the measurement of the pulse wave velocity of the brachial ankle artery, We recommend suspected vascular stenosis and perform a cerebral artery angiography. It is suggested that the data will be used as a baseline data for similar studies after evaluating the significance of blood pressure, obesity, and abdominal obesity as risk factors of atherosclerosis.

Changes in the Lung after Pulmonary Hypertension Induced by Obstruction of the Pulmonary Vein in Rats (흰쥐에서 폐정맥 폐쇄에 의해 유도된 폐동맥고혈압 발생 후의 폐장의 변화)

  • Jang Won-Chae;Jeong In-Suk;Cho Kyu-Sung;Oh Bong-Suk
    • Journal of Chest Surgery
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    • v.39 no.9 s.266
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    • pp.659-667
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    • 2006
  • Background: Experimental studies of vascular remodeling in the pulmonary arteries have been performed actively. These models required a persistent vascular insult for intimal injury induced by chronic hypoxia, monocrotaline intoxication or chronic air embolism and characterized medial hypertrophy and neointimal formation by active synthesis of the extracellular matrix protein. The purpose of this study was to determine the pattern of pulmonary vascular remodeling after obstruction of the pulmonary vein. Material and Method: Obstruction of the right pulmonary vein with a metal clip was performed in Sprague-Dawley rats $(352{\pm}18g,\;n=10)$ to cause pulmonary vascular disease. Fifteen days later, experimental studies were done and finally the both lungs and hearts were extirpated for experimental measurement. Pulmonary arterial pressure, weight ratio of right ventricle (RV) to left ventricle (LV) and ventricular septum (S) (RV/LV +S weight ratio), and pulmonary artery morphology (percent wall thickness, %WT) were evaluated and compared with normal control groups. Result: Pulmonary hypertension $(38{\pm}12mmHg\;vs\;13{\pm}4mmHg;\;p<0.05)$ and right ventricular hypertrophy (right ventricular/left ventricular and septal weight ratio, $0.52{\pm}0.07\;vs\;0.35{\pm}0.04;\;p<0.05$) with hypertrophy of the muscular layer of the pulmonary arterial wall (percent wall thickness, $22.4{\pm}6.7%\;vs\;6.7{\pm}3.4%;\;p<0.05$) were developed by 15 days after obstruction of the pulmonary vein. Conclusion: Obstruction of the pulmonary vein developed elevation of pulmonary blood pressure and medial hypertrophy of the pulmonary artery. These results are a part of the characteristic vascular remodeling. Theses results demonstrate that obstruction of the pulmonary vein can develope not only high pulmoanry blood flow of contralateral lung but also intima injury inducing vascular remodeling.

Multimodal Bio-signal Measurement System for Sleep Analysis (수면 분석을 위한 다중 모달 생체신호 측정 시스템)

  • Kim, Sang Kyu;Yoo, Sun Kook
    • Journal of Korea Multimedia Society
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    • v.21 no.5
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    • pp.609-616
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    • 2018
  • In this paper, we designed a multimodal bio-signal measurement system to observe changes in the brain nervous system and vascular system during sleep. Changes in the nervous system and the cerebral blood flow system in the brain during sleep induce a unique correlation between the changes in the nervous system and the blood flow system. Therefore, it is necessary to simultaneously observe changes in the brain nervous system and changes in the blood flow system to observe the sleep state. To measure the change of the nervous system, EEG, EOG and EMG signal used for the sleep stage analysis were designed. We designed a system for measuring cerebral blood flow changes using functional near-infrared spectroscopy. Among the various imaging methods to measure blood flow and metabolism, it is easy to measure simultaneously with EEG signal and it can be easily designed for miniaturization of equipment. The sleep stage was analyzed by the measured data, and the change of the cerebral blood flow was confirmed by the change of the sleep stage.

Measurement and Clinical Analysis of Carotid Intima, Media and Intima-Media Thickness

  • Kim, Wuon-Shik;Jeong, Hwan-Taek;Bae, Jang-Ho
    • International Journal of Vascular Biomedical Engineering
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    • v.3 no.1
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    • pp.6-13
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    • 2005
  • Individual clinical significance of each layer of CCA (common carotid artery) has not been well studied. We intended to measure the intima thickness (IT), media thickness (MT), and intima-media thickness (IMT) of CCA separately and tried to analyze the clinical significance. One hundred fifty one consecutive patients (mean age: $57{\pm}15$ years; 77 males, 74 females) underwent CCA scanning using high-resolution ultrasound. The images were off-line analyzed using B-mode ultrasound image processing, devised for individual measurement of IT and MT as well as IMT. The mean coefficients of variation of new method measuring IT, MT, and IMT separately were 0.16% for IMT and 0.21% for both IT and MT. The IT (p < 0.01), MT (p < 0.01) as well as IMT (p < 0.001) of patients with atherosclerotic disease were significantly thicker than that of the patients without atherosclerotic disease. Patients with hypertension showed significantly thicker IT (p < 0.01), MT (p < 0.001), and IMT (p < 0.001) than that of the patients without hypertension. However, only IT was thicker in patients with smoking (p<0.01) than that of the patients without smoking.

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A Study on the Direction of Evaluation Indicators for Personalized Beauty Self-care

  • Lee, Yoo-jeong;Choi, Ji-woo;Shin, Sae-young
    • Journal of Fashion Business
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    • v.24 no.6
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    • pp.120-134
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    • 2020
  • Recently, the beauty industry has implemented personalized services based on skin big data. To increase competitiveness in the beauty industry, systematic data measurement and evaluation indicators are necessary to select data and obtain necessary knowledge. In response, this study sought to stably enhance the accuracy of skin diagnosis based on satisfaction and reliability. To this end, the research was conducted through focus group interviews (FGI), a case study of brands, and analysis of prior research results. In particular, as a result of analyzing keywords that classify skin types by brand, common survey items for skin types were oiliness and using moisturizer, cosmetic use and vascular of skin, external stimulus and blemish & freckles, facial wrinkle, outside activities, self-consciousness, and smoke. In additioin to the common questions of the preceding study and the brand survey items, the questions concerning complex skin types, seasonal change, facial color, wrinkles and elasticity were added, and the questions were presented in a total of 40 items. In particular, it suggested that skin measurement could be conducted by focusing on elasticity and pigmentation items by reflecting the results of prior research and the opinions of FGI, and based on this, a customized service with high satisfaction and high accuracy of beauty care based on this could be proposed. We hope that this study will facilitate active self-care by providing more satisfying skin stones and personalized cosmetics proposals, thus laying the foundation for the further development of the cosmetics industry.

Reproducibility of Regional Pulse Wave Velocity in Healthy Subjects

  • Im Jae-Joong;Lee, Nak-Bum;Rhee Moo-Yong;Na Sang-Hun;Kim, Young-Kwon;Lee, Myoung-Mook;Cockcroft John R.
    • International Journal of Vascular Biomedical Engineering
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    • v.4 no.2
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    • pp.19-24
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    • 2006
  • Background: Pulse wave velocity (PWV), which is inversely related to the distensibility of an arterial wall, offers a simple and potentially useful approach for an evaluation of cardiovascular diseases. In spite of the clinical importance and widespread use of PWV, there exist no standard either for pulse sensors or for system requirements for accurate pulse wave measurement. Objective of this study was to assess the reproducibility of PWV values using a newly developed PWV measurement system in healthy subjects prior to a large-scale clinical study. Methods: System used for the study was the PP-1000 (Hanbyul Meditech Co., Korea), which provides regional PWV values based on the measurements of electrocardiography (ECG), phonocardiography (PCG), and pulse waves from four different sites of arteries (carotid, femoral, radial, and dorsalis pedis) simultaneously. Seventeen healthy male subjects with a mean age of 33 years (ranges 22 to 52 years) without any cardiovascular disease were participated for the experiment. Two observers (observer A and B) performed two consecutive measurements from the same subject in a random order. For an evaluation of system reproducibility, two analyses (within-observer and between-observer) were performed, and expressed in terms of mean difference ${\pm}2SD$, as described by Bland and Altman plots. Results: Mean and SD of PWVs for aorta, arm, and leg were $7.07{\pm}1.48m/sec,\;8.43{\pm}1.14m/sec,\;and\;8.09{\pm}0.98m/sec$ measured from observer A and $6.76{\pm}1.00m/sec,\;7.97{\pm}0.80m/sec,\;and\;\7.97{\pm}0.72m/sec$ from observer B, respectively. Between-observer differences ($mean{\pm}2SD$) for aorta, arm, and leg were $0.14{\pm\}0.62m/sec,\;0.18{\pm\}0.84m/sec,\;and\;0.07{\pm}0.86m/sec$, and the correlation coefficients were high especially 0.93 for aortic PWV. Within-observer differences ($mean{\pm}2SD$) for aorta, arm, and leg were $0.01{\pm}0.26m/sec,\;0.02{\pm}0.26m/sec,\;and\;0.08{\pm}0.32m/sec$ from observer A and $0.01{\pm}0.24m/sec,\;0.04{\pm}0.28m/sec,\;and\;0.01{\pm}0.20m/sec$ from observer B, respectively. All the measurements showed significantly high correlation coefficients ranges from 0.94 to 0.99. Conclusion: PWV measurement system used for the study offers comfortable and simple operation and provides accurate analysis results with high reproducibility. Since the reproducibility of the measurement is critical for the diagnosis in clinical use, it is necessary to provide an accurate algorithm for the detection of additional features such as flow wave, reflection wave, and dicrotic notch from a pulse waveform. This study will be extended for the comparison of PWV values from patients with various vascular risks for clinical application. Data acquired from the study could be used for the determination of the appropriate sample size for further studies relating various types of arteriosclerosis-related vascular disease.

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Micro-PIV Measurements of In Vitro Blood Flow in a Micro-Channel

  • Park, Cheol-Woo;Lee, Sang-Joon;Shin, Se-Hyun
    • International Journal of Vascular Biomedical Engineering
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    • v.1 no.2
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    • pp.30-35
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    • 2003
  • Flow characteristics of blood flow in a micro channel were investigated experimentally using a micro-PIV (Particle Image Velocimetry) velocity field measurement technique. The main objective of this study was to understand the real blood flow in micron-sized blood vessels. The Reynolds number based on the hydraulic diameter of micro-channel for deionized (DI) water was about Re=0.34. For each experimental condition, 100 instantaneous velocity fields were captured and ensemble-averaged to get the spatial distributions of mean velocity. In addition, the motion of RBC (Red Blood Cell) was visualized with a high-speed CCD camera. The captured flow images of nano-scale fluorescent tracer particles in DI water were clear and gave good velocity tracking-ability. However, there were substantial velocity variations in the central region of real blood flow in a micro-channel due to the presence of red blood cells.

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