• Archives of Plastic Surgery
• /
• 제32권6호
• /
• pp.689-698
• /
• 2005

Many studies for verifying angiogenesis have been in progress, especially in the field of abnormal vascular proliferation to explain the pathogenesis and to develop a treatment of several diseases. In our previous experiments, endothelial cell proliferations were induced by DMH stimulation in vitro, and the 177 factors(142 up-regulated and 35 down-regulated factors) were identified. Among the up-regulated factors, 9 substances (EFEMP1, CTGF, CYR61, $ITG{\beta}1$, FHL2, SERPINE1, MYC, PTTG1 and MSH6) were selected, which were related to cell proliferation and showed high signal intensities. The RNA was isolated from HUVECs at the time of 0, 6, 12, 24 hours after the DMH treatment, and RNA of control group HUVECs was also isolated. Genetic information of selected molecules was used to make primer for each, and RT-PCR was performed to analyze both groups. In control and treatment groups, each substance presented variety of manifestation degree according to time differences. EFEMP1, CTGF, CYR61, $ITG{\beta}1$, FHL2 and MYC were related to abnormal vascular proliferation steadily and SERPINE1, PTTG1 and MSH6 were related secondarily. CTGF was related to both normal and abnormal proliferation, but it played a more significant role in abnormal proliferation from earlier stage. EFEMP1, CYR61, $ITG{\beta}1$, FHL2 and MYC were similar to CTGF, although the relation appeared lately. Further study should be performed to analyze the expressions and the interactions of growth factors, which could be utilized in the new therapeutic development.

• Archives of Plastic Surgery
• /
• 제34권1호
• /
• pp.8-12
• /
• 2007

Purpose: Protein tyrosine kinase(PTK), protein kinase C(PKC), oxidase, as a mediator, have been known to take a role in signal transduction pathway of angiogenesis. The authors confirmed that PKC is the most noticeable mediator for abnormal proliferation of vascular endothelial cells through in vitro study model using the inhibitors, targeting the formation of three co-enzymes. In this study, we would investigate which isoform of PKC play an important role in abnormal angiogenesis of vascular endothelial cell. Methods: In 96 well plates, $10^4$ HUVECs(human umbilical vein endothelial cells) were evenly distributed. Two groups were established; the control group without administration of DMH(1,2-dimethylhydrazine) and the DMH group with administration of $7.5{\times}10^{-9}M$ DMH. RNA was extracted from vascular endothelial cell of each group and expression of the PKC isoform was analyzed by RT-PCR(reverse transcriptase-polymerase chain reaction) method. Results: RT-PCR analysis showed that $PKC{\alpha}$, $-{\beta}I$, $-{\beta}II$, $-{\eta}$, $-{\mu}$ and $-{\iota}$ were expressed in vascular endothelial cells of each group. DMH incresed the expression of $PKC{\alpha}$ and $PKC{\mu}$, and decreased $PKC{\beta}I$, $PKC{\beta}II$ expression dominantly. Conclusion: Based on the result of this study, it was suggested that $PKC{\alpha}$ and $PKC{\mu}$ may have significant role in abnormal proliferation of vascular endothelial cell.

• 융합신호처리학회논문지
• /
• 제12권2호
• /
• pp.96-101
• /
• 2011

최근 들어 실시간 원격 ECG모니터링 시스템에 대한 수요가 늘어가고 있으며 가입자의 증가와 더불어 실시간 모니터링 시스템의 자동화에 대한 필요성이 대두되고 있다. 비정상적인 ECG 비트의 자동검출은 이러한 실시간 원격 ECG모니터링 시스템의 성공적인 상업화를 위해서는 반드시 필요한 요소기술이다. 본 논문에서는 이러한 점에 착안하여 QRS 폭(width)과 RR interval의 패턴을 이용한 효율적인 비정상적 ECG 비트 자동검출알고리듬을 제안하였다. 기존에는 주로 ECG 비트의 상세한 분류에 대해서 많은 연구가 이루어졌으나 이러한 방법들은 분류 오류가 많고 주변 환경이 변화함에 따라서 분류성능의 변동성이 심하다는 단점이 있었다. 또한 정확한 ECG 비트 분류를 위해서는 충분한 양의 훈련데이터를 필요로 하며 특히 분류시에 많은 계산량을 필요로 한다는 문제점도 있었다. 그러나 자동화된 원격 ECG모니터링 시스템을 위해서는 ECG 비트의 세세한 분류 보다는 비트의 정상여부판단이 더 중요하다. 이러한 점에 착안하여 본 논문에서는 ECG 신호의 비정상적인 비트중에서도 가장 빈번이 발생하는 VEBs(Ventricular ectopic beats) 비트의 검출을 시도하였고 제안된 알고리듬을 MIT-BIH 부정맥 데이터베이스에 적용한 결과 만족스러운 VEBs 바트 검출성능을 얻을 수 있었다.

• Journal of Photoscience
• /
• 제2권2호
• /
• pp.63-67
• /
• 1995

Zinc plays a key role in genetic expression, cell division, and growth and is essential for the function of more than 200 enzymes; effects of zinc deficiency induce many syndromes, including abnormal visual adaptation. The pigment epithelium (EP) contains high concentrations of zinc in humans and in animals and it participates in threshold elevation, visual sensitivity increment, and acceleration of rhodopsin regeration during visual adaptation. The origin of c-wave of electroretinogram(ERG) is not only pigment epithelium as shown in present research, but also other cell layers, perhaps the photoreceptors. We propose zinc as a candidate for an internal messenger which participates in signal amplification.

• 대한의용생체공학회:의공학회지
• /
• 제14권4호
• /
• pp.379-386
• /
• 1993

This paper describes design of a Chaos analyser and its applications to analysis of nonlinear characteristirs of ECG. The proposed system can easily distinguish chaotic system among the various dynamical systems by chaotic quantitative and qualitative analysis and also chaotic characteristics which represents states of nonlinear dynamical system. And we have also proposed new possibilities to recognize abnormal state of ECG signal using the chaotic characteristics.

• 대한의용생체공학회:의공학회지
• /
• 제11권1호
• /
• pp.75-82
• /
• 1990

The purpose of this study is to help the hearing Impaired's speech training with a visible speech processing system. In brief, this system converts the features of speech signals into graphics on monitor, and adjusts the features of hearing impaired to normal ones. There are formant and pitch in the features used for this system. They are extracted using the digital signal processing such as linear predictive method or AMDF(Average Magnitude Difference Function). In order to effectively train for the hearing impaired's abnormal speech, easilly visible feature has been being studied.

• 비파괴검사학회지
• /
• 제23권2호
• /
• pp.116-124
• /
• 2003

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
• /
• pp.962-964
• /
• 2003

In this paper, development of portable power interrupt tester to evaluate microprocessor based control circuits for an endurance under abnormal power source. 89C2051 micro-controller is performed to make power interrupt signal, and software controls peripheral hardwares and built-in functions. Experimental results of this study will offer a good application to electronic appliance maker as a test device of hardware and software debugging use.

• 대한안전경영과학회지
• /
• 제3권4호
• /
• pp.113-122
• /
• 2001

This study is to examine the effect of layoff on shareholders' wealth. Firms make layoff decisions by reason of cost cutting, lower performance, demand decline, restructuring. Therefore, I think that stock market responds to layoff positively, since the firm's labor productivity and profitability is improved after execution of layoff, I find that layoff variables effect on abnormal return positively in regression analysis. This means that layoff sends positive signal to the stock market for the firm's future performance. Therefore, layoff has a good effect on shareholders' wealth.

• 한국컴퓨터정보학회:학술대회논문집
• /
• 한국컴퓨터정보학회 2019년도 제60차 하계학술대회논문집 27권2호
• /
• pp.161-162
• /
• 2019

본 논문에서는 변압기의 이상 신호 데이터를 원거리에서 축적하기 위한 이상 신호 진단 시스템을 제안한다. 이 시스템은 원격으로 변압기의 이상 신호를 수집하여 변압기의 이상을 알아낼 수 있다. 이 시스템은 상용된 통신 모듈의 느린 통신 속도를 고려하여 이상 신호를 RMS-DC 값으로 변환하는 작업을 추가하였다.