• Title/Summary/Keyword: Vascular

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Comparison of peripheral vascular compliance between normal and diabetic group using second derivative of photoplethysmogram (PPG 2차 미분을 이용한 정상인과 당뇨병 환자의 말초혈관 탄성도 비교)

  • Kim, Sung-Woo;Lee, Ju-Hyung;Kang, Eun-Seok;Kim, Soo-Chan;Kim, Deok-Won
    • Proceedings of the KIEE Conference
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    • 2007.04a
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    • pp.67-69
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    • 2007
  • Recently, the prevalence rate of diabetes in Korea has been increasing rapidly due to high growth of economy and changes in dietary lifestyle. Vascular complication is one of diabetic complications which have frequently occurred by obesity, hyperglycemia and impaired glucose metabolism. Photoplethysmogram(PPG) measured from finger and toe is very useful for evaluation of vascular aging and sclerosis level since the PPG signal represents characteristics of peripheral vascular. Several researchers have reported that second derivative of the finger PPG waveform was useful to evaluate vascular compliance and developed various analysis methods for vascular compliance. However, peripheral vascular compliance study for diabetic patient was never evaluated by using second derivative of PPG. Therefore, we aimed to objectively compare and to assess normal and diabetic group vascular compliance using the second derivative of PPG waveform in this study. The evaluated factors of second derivative of PPG are 'a', 'b', 'c', 'd', 'e' and b/a represents vascular compliance. Study found out that when vascular compliance is decreased, b/a is increased, the absolute value of b/a is decreased. The average vascular compliance of 50 diabetic patients with neuropathy is statistically lower than the normal group(p<0.05). We suggest an objective evaluation of peripheral vascular compliance for diabetic patients and prevention of vascular complication.

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A Direction-Based Vascular Pattern Extraction Algorithm for Hand Vascular Pattern Verification

  • Im, Sang-Kyun;Choi, Hwan-Soo;Kim, Soo-Won
    • ETRI Journal
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    • v.25 no.2
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    • pp.101-108
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    • 2003
  • This paper proposes an improved vascular pattern extraction algorithm for person verification applications. The proposed direction-based vascular pattern extraction (DBVPE) algorithm is based on the directional information of vascular patterns. It applies two different filters to the input images: row vascular pattern extraction filter (RVPEF) for effective extraction of the abscissa vascular patterns and column vascular pattern extraction filter (CVPEF) for effective extraction of the ordinate vascular patterns. We use the combined output of both filters to obtain the final hand vascular patterns. Unlike the conventional hand vascular pattern extraction algorithm, the directional extraction approach prevents loss of the vascular pattern connectivity. To validate the DBVPE algorithm, we used a prototype system with a DSP processor. The prototype system shows approximately a three-times better false acceptance rate (FAR) than the conventional single filter algorithm.

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Targeted Protein Expression in Freshly Isolated Vascular Tissues by Using Adenoviral Vector (생체에서 분리된 혈관조직에서 아데노바이러스벡터를 이용한 특정 단백질의 발현)

  • Huh, Yang Hoon;Kim, Hak Rim
    • YAKHAK HOEJI
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    • v.57 no.4
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    • pp.265-271
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    • 2013
  • Treatments of vascular disease via modulating the expression of specific proteins by gene transfer have been attempted in various studies over the past few years. Among several methods to deliver genes, adenovirus currently has been used because of a number of positive aspects. In this study, we test adenoviral vector as a potential mediator in the treatment of vascular disease by using freshly isolated vascular tissues not cultured vascular cells. Freshly isolated vascular tissues were directly exposed to adenoviral vector pAd5CMVmcsIRESeGFPpA to check the possibility of GFP expression in different layer of vascular tissues. We found that the GFP expression by using adenoviral vector experiments is mainly focused on the adventitia and failed to detect GFP expression at endothelial layer or vascular smooth muscle layer in vascular tissues. However, we also found that several integrin receptors are robustly expressed in vascular smooth muscle, thus the limited expression of protein in vascular smooth muscle are not likely the lack of integrin receptors. In conclusion, adenovirus could not be a good tool for a specific protein expression in vascular smooth muscle cell. Thus, the application of adenovirus as a tool for gene therapy of vascular smooth muscle cells in clinical therapeutic trial need to be optimized further.

Vascular Dementia (혈관성 치매)

  • Kim, Tae Woo;Kwak, Kyung Phil
    • Korean Journal of Biological Psychiatry
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    • v.23 no.3
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    • pp.80-88
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    • 2016
  • Vascular dementia is a very frequent form of dementia. Debates over classification and diagnostic criteria, and controversy over identifiable treatment targets will continue until distinct pathophysiological mechanism of vascular dementia is found. Clinical diagnostic criteria are sufficiently strong to be useful for clinical trials, but need further refinement. Cognitive changes in vascular dementia are more variable than other disorders, and are dependent on the vascular pathology. Accurate diagnosis of vascular dementia is known to need the presence of reliable cerebrovascular disease on brain imaging. Although it seems obvious that cerebrovascular disease causes pathological damage and impaired cognition, it is very difficult to find the accurate contribution of cerebrovascular pathology to cognitive decline. Most studies have shown a small but significant benefit of cholinesterase inhibitors on cognition, the significance of this effect has been slight and benefits on global functioning, activities of daily living, and behaviour have not been consistently reported. Management of vascular dementia should focus on identifying and managing vascular risk factors.

A Study on Estimate Vascular Compliance using Acceleration Photoplethymogram (가속도 맥파를 이용한 혈관탄성 추정에 관한 연구)

  • Lee, Chung-Luyl;Kim, Kyung-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.6
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    • pp.840-844
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    • 2013
  • In this study, we try to estimate vascular compliance for management vascular disease. Because It is known the vascular compliance represents the state of the blood vessels. In general, the vascular compliance is estimated using an acceleration photoplethymogram from measured by photoplethymogram-based. The acceleration photoplethymogram is come from second derivative of photoplethymogram. By using the acceleration photoplethymogram, we can estimating vascular compliance, vascular age, vascular state. In this study, for measuring acceleration photoplethymogram we have developed a measurement device having analog filters. It has the advantage of miniaturization, low-power because it is simpler than digital filters. Using the developed device, we have estimated vascular compliance and tested the reliability of our device compare with conventional device having digital filters. As a result.

Comparison of vascular compliance between normal and replanted fingers using second derivative of photoplethysmogram (PPG 2차 미분을 이용한 정상과 재접합 손가락의 혈관 탄성도 비교)

  • Kim, Sung-Woo;Kim, Jin-Tae;Hong, Hyun-Ki;Kim, Soo-Chan;Kim, Deok-Won
    • Proceedings of the KIEE Conference
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    • 2006.04a
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    • pp.42-44
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    • 2006
  • Up to the present, finger replantation patients have complained about various symptoms because of blood circulatory failure. Objective evaluation methods for the level of the blood circulatory failures in fingers were needed other than patient's subjective symptoms and complaints. Photoplethysmogram(PPG) measured from fingers is very useful for evaluation of vascular aging and sclerosis level since the PPG signal represents characteristics of peripheral vascular. Several researchers have reported that second derivative of the finger PPG waveform was useful to evaluate vascular compliance and developed various analysis methods for vascular compliance. However, vascular compliance study for finger replantation patient was never evaluated by using second derivative of PPG. Therefore, we aimed to objectively compare and to assess normal and replanted finger vascular compliance using the second derivative of PPG waveform in this study. The evaluated factors of second derivative of PPG are 'a', 'b', 'c', 'd', 'e' and b/a represents vascular compliance. Study found out that when vascular compliance is decreased, b/a is increased, the absolute value of b/a is decreased. For 43 finger replantation patients, the average vascular compliance of replanted finger is lower than the normal finger statistically(p=0.001). we suggested an objective evaluation of finger vascular compliance for finger replantation patients and effect of surgical operation.

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Vascular anomalies of the head and neck: current overview

  • Lee, Jeong Woo;Chung, Ho Yun
    • Archives of Craniofacial Surgery
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    • v.19 no.4
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    • pp.243-247
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    • 2018
  • Vascular anomalies are disorders of the endothelium and surrounding cells that can affect the vasculature and involve any anatomical structure. The most common problem associated with vascular anomalies is psychological distress related to disfigurement as well as functional defects, as many lesions affect the head and neck. This article provides an overview of the current clinical features that distinguish the major types of vascular anomalies that affect the head and neck.

Vascular Transition and Hypocotyl Elongation in Soybean(Glycin max) Seedlings (대두(Glycine max) 유식물에서 하배축의 신장과 유관속전이)

  • 강경덕
    • Journal of Plant Biology
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    • v.34 no.4
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    • pp.274-281
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    • 1991
  • The relationship between elongation of hypocotyl and its vascular transition was studied with seedling of Glycine max. the hypocotyl elongation proceeded acropetally from the base of hypocotyl toward the cotyledonary node. The vascular transition did not occur in the basal region of the hypocotyl, which did not nearly elongate, with exarch radial vascular bundles. However, the vascular transition was almost completed at the middle part of the hypocoty, more or less elongated, with endarch collateral vascular bundles. Such bundles also appeared in the uppermost region of the hypocotyl, in which the elongation was the most striking. These results suggested that the vascular transition was related to the hypocotyl elongation and that the transition of primary vascular system in Glycine max seedling was established by rather rapid process. Our observations of the serial sections from root to hypocotyl revealed that the vascular system through the root-hypocotyl-cotyledon was a unit, to which one of the epicotyl that did not participate in transition was superimposed.

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Poly(ADP-ribose) protects vascular smooth muscle cells from oxidative DNA damage

  • Zhang, Chao;Luo, Tao;Cui, Shijun;Gu, Yongquan;Bian, Chunjing;Chen, Yibin;Yu, Xiaochun;Wang, Zhonggao
    • BMB Reports
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    • v.48 no.6
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    • pp.354-359
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    • 2015
  • Vascular smooth muscle cells (VSMCs) undergo death during atherosclerosis, a widespread cardiovascular disease. Recent studies suggest that oxidative damage occurs in VSMCs and induces atherosclerosis. Here, we analyzed oxidative damage repair in VSMCs and found that VSMCs are hypersensitive to oxidative damage. Further analysis showed that oxidative damage repair in VSMCs is suppressed by a low level of poly (ADP-ribosyl)ation (PARylation), a key post-translational modification in oxidative damage repair. The low level of PARylation is not caused by the lack of PARP-1, the major poly(ADP-ribose) polymerase activated by oxidative damage. Instead, the expression of poly(ADP-ribose) glycohydrolase, PARG, the enzyme hydrolyzing poly(ADP-ribose), is significantly higher in VSMCs than that in the control cells. Using PARG inhibitor to suppress PARG activity facilitates oxidative damage-induced PARylation as well as DNA damage repair. Thus, our study demonstrates a novel molecular mechanism for oxidative damage-induced VSMCs death. This study also identifies the use of PARG inhibitors as a potential treatment for atherosclerosis. [BMB Reports 2015; 48(6): 354-359]