염증성 관절염에서 NO 의 역할에 관한 연구

배상철(Sang Cheol Bae),김동욱(Dong Yook Kim),김태환(Tae Hwan Kim),전재범(Jae Bum Jun),정성수(Sung Soo Jung),이인홍(In Hong Lee),유대현(Dae Hyun Yoo),김성윤(Seong Yoon Kim),이은영(Eun Young Lee),장성렬(Sung Yeoul Chang) 대한내과학회 1997 대한내과학회지 Vol.52 No.1

N/A Objectives: Nitric Oxide(NO) is a toxic, inorganic, gaseous free radical produced during the metabolism of L-Arginine by NO synthase(NOS). It has been implicated in a rapidly growing number of physiological and pathophysiological processes such as cytotoxic effects against microbes and tumor cells, blood vessel dilation and neurotransmitter. Recently there is growing evidence implicating NO in immune regulation, inflammation, autoimmunity, and arthritis. We performed this study to determine a role for nitric oxide in inflammatory arthritis especially rheumatoid arthritis(RA). Methods: We measured (D the concentrations of nitrite, a breakdown product of nitric oxide, in serum and synovial fluid from patients with RA and osteoarthritis(OA) and in the serum of controls ② the concentrations of nitrite in the supernatant of cultured synovial tissue with RA and OA and ③ determined whether human chondrocytes and synoviocytes can synthesize nitric oxide and if so, how production is regulated by cytokines and antirheumatic drugs. Results: 1) Serum nitrite concentrations in patients with RA and OA were higher than in controls. In both disease groups synovial fluid nitrite was higher than serum nitrite. Serum and synovial fluid nitrite concenrations in RA were higher than those in OA. However, those findings are not statistically significant. 2) Although these findings are not statistically significant, the concentration of nitrite in the supernatant of cultured synavial tissue with RA was higher than that in OA. 3) IL-l5 and TNF-a induced the biosynthesis of NO by chondrocytes and synoviocytes. IGF-1 and TGF-5 failed to provoke the production of NO. The biosynthesis of NO required an induction period of approximately 6 hours and was inhibited by L- NMMA and cycloheximide. Dexamethasone, indomethacin, gold sodium thiomalate and methotrexate had no effect on the induction of NO biosynthesis. Conclusion: These results suggest a role for nitric oxide as an inflommatory mediator in inflammatory arthritis.

웨이브렛 영역에서 신호 복원을 위한 잡음제거 알고리즘

배상범(Sang-Bum Bae),류지구(Ji-Goo Ryu),김남호(Nam-Ho Kim) 제어로봇시스템학회 2006 제어로봇시스템학회 합동학술대회 논문집 Vol.2006 No.12

개선된 에지검출 특성을 위한 웨이브렛 함수에 관한 연구

배상범,김남호,Bae, Sang-Bum,Kim, Nam-Ho 한국정보통신학회 2007 한국정보통신학회논문지 Vol.11 No.6

영상에서 명암 차이가 큰 두 영역간의 경계를 나타내는 에지는 대상 물체에 대한 다양한 정보를 포함한다. 따라서 영상분할을 비롯한 물체인식 등의 분야에서 이러한 에지정보를 이용하고 있다. 에지는 밝기 변화의 크기와 지속시간 등에 따라 다양한 종류가 있으며, 일반적으로 미분을 통해 검출된다. 최근에는 영상처리와 컴퓨터비전 등의 분야에서, 특정 응용에 적용하기 위한 에지검출 방법들이 제시되고 있다. 따라서 본 논문에서는 개선된 에지검출 특성을 위한 웨이브렛 함수를 제안하여, 영상의 라인-에지 성분을 검출하였으며, 시뮬레이션을 통해 그 성능을 확인하였다. Edge representing the boundary between two regions with the large briskness difference in mage includes diverse information about object. Therefore, this information has been utilized in fields such as image segmentation and object recognition. There are many kinds of edge according to duration time and the amplitude of brightness variation and edge is generally detected through the differential. Recently, in fields of image processing and computer vision, edge detection methods have been proposed to use in specific applications. Hence, in this paper the wavelet function for improved edge detection properties was proposed and detected line-edge components of images and its performance was proven through simulations.

Wavelet-based Algorithm for Signal Reconstruction

배상범,김남호,Bae, Sang-Bum,Kim, Nam-Ho The Korea Institute of Information and Commucation 2007 한국정보통신학회논문지 Vol.11 No.1

Noise is generated by several causes, when signal is processed. Hence, it generates error in the process of data transmission and decreases recognition ratio of image and speech data. Therefore, after eliminating those noises, a variety of methods for reconstructing the signal have been researched. Recently, wavelet transform which has time-frequency localization and is possible for multiresolution analysis is applied to many fields of technology. Then threshold-and correlation-based methods are proposed for removing noise. But, conventional methods accept a lot of noise as an edge and are impossible to remove the additive white Gaussian noise (AWGN) and the impulse noise at the same time. Therefore, in this paper we proposed new wavelet-based algorithm for reconstructing degraded signal by noise and compared it with conventional methods. 신호를 처리하는 과정에서 여러 가지 원인에 의해 잡음이 발생하고 있으며, 이에 따라 전송 데이터에서 오류가 발생하거나, 영상 및 음성 데이터의 인지도를 저하시킨다. 따라서 이러한 잡음들을 제거하여 신호를 복원하기 위한 다양한 방법들이 연구되고 있다. 현재, 시간-주파수 국부성을 갖고, 다중해상도 해석이 가능한 웨이브렛 변환이 많은 공학 분야에서 응용되고 있으며, 잡음 제거를 위해 문턱값과 상관관계를 이용한 방법 등이 제시되었다. 그러나 기존의 방법들은 여전히 많은 잡음들을 에지로서 판단하며, AWGN과 임펄스 잡음을 동시에 제거하기 위한 방법을 제공하지 않는다. 따라서 본 논문에서는 잡음에 의해 훼손된 신호를 복원하기 위하여, 새로운 웨이브렛기반 알고리즘을 제시하였으며, 기존의 방법들과 비교하였다.

웨이브렛 스펙트럼 분석을 이용한 신호의 특징 검출

배상범,김남호,Bae Sang-Bum,Kim Nam-Ho 한국정보통신학회 2006 한국정보통신학회논문지 Vol.10 No.4

In various fields of basic science and engineering, in order to present signals and systems exactly and acquire useful information from spatial and timely changes, many researches have been processed. In these methods, the Fourier transform which represents signal as the combination of the frequency component has been applied to the most fields. But as transform not to consider time information, the Fourier transform has its limitations of application. To overcome this problem, a variety of methods including the wavelet transform have been proposed. As transform to represent signal by using the changing window, according to scale parameter in time-scale domain, the wavelet transform is capable of multiresolution analysis and defines various functions according to the application environments. In this paper, to detect features of signal we analyzed wavelet the spectrum by using the basis function of the fourier transform. 기초과학과 공학의 다양한 분야에서, 신호와 시스템을 정확하게 표현하고, 신호의 공간적, 시간적 변화로부터 유용한 정보를 획득하기 위한 많은 연구들이 수행되어 왔다. 이러한 분석 방법들에서, 신호를 주파수 성분들의 조합으로서 표현하는 퓨리에 변환은 가장 많은 분야에서 응용되고 있다. 그러나 퓨리에 변환은 시간 정보를 고려하지 않는 변환으로서 응용의 한계성을 지니고 있으므로 이를 극복하기 위해, 웨이브렛 변환을 비롯한 다양한 방법들이 제시되었다. 웨이브렛 변환은 스케일 변수에 따라 변화하는 윈도우를 사용하여 신호를 시간-스케일 공간상에서 표현하는 변환으로서, 다중해상도 분석이 가능하며, 응용환경에 따라 다양한 형태의 함수를 정의할 수 있다. 따라서 본 논문에서 신호의 특징을 검출하기 위해, 퓨리에 변환의 기저함수를 사용하여 웨이브렛 스펙트럼을 분석하였다.

웨이브렛 근사계수 기반의 분포특성을 이용한 잡음 제거 방법에 관한 연구

배상범,김남호,Bae, Sang-Bum,Kim, Nam-Ho 한국정보통신학회 2010 한국정보통신학회논문지 Vol.14 No.2

잡음에 의한 열화현상은 디지털화된 데이터의 인지도를 저하시킨다. 따라서 신호의 에지 성분을 보존함과 동시에 잡음을 제거하기 위한 시간영역과 주파수영역의 다양한 방법들이 사용되고 있다. 본 논문에서는 신호에 중첩된 복합적인 잡음을 감소시키기 위해, 웨이브렛 근사 계수를 이용한 새로운 잡음 제거 알고리즘을 제안하였다. 제안된 알고리즘에서는 신호의 에지와 잡음에 대한 구분 성능을 향상시키기 위해, 웨이브렛 근사계수의 누적으로부터 얻어지는 오차함수의 분포특성을 이용하였다. The degradation phenomenon caused by noises significantly corrupts digitalized data. Therefore, a variety of methods to preserve the edge component of signals and remove noise simultaneously have been used in time domain and frequency domain. In this paper, we have proposed a new noise reduction algorithm using wavelet approximation coefficients to reduce the mixed noise overlapping the signal. The proposed algorithm adopts the distribution characteristics of the error function which is obtained by accumulating the wavelet approximation coefficients, in order to improve the capability to separate edges of the signal and noises.

웨이브렛을 이용한 신호 분석에 관한 연구

배상범(Sang-Bum Bae),류지구(Ji-Goo Ryu),김남호(Nam-Ho Kim) 제어로봇시스템학회 2005 제어로봇시스템학회 합동학술대회 논문집 Vol.2005 No.12

웨이브렛을 이용한 가우시안 잡음 제거 알고리즘에 관한 연구

배상범(Sang-Bum Bae),류지구(Ji-Goo Ryu),김남호(Nam-Ho Kim) 제어로봇시스템학회 2004 제어로봇시스템학회 합동학술대회 논문집 Vol.2004 No.12

류마티스 관절염 환자의 활막세포에서 TNF-α에 의해 활성화된 Nuclear Factor κB에 대한 N-(2-mercapto-2-methylpropanoyl)-L-Cysteine(bucillamine)의 효과

전재범 ( Jae Bum Jun ),유대현 ( Dae Hyun Yoo ),이은영 ( Eun Young Lee ),고희관 ( Hee Kwan Koh ),김태환 ( Tae Hwan Kim ),정자헌 ( Ja Hun Jung ),장대국 ( Dae Kook Chang ),배상철 ( Sang Cheol Bae ),최영길 ( Yong Keel Choi ),김성윤 ( 대한류마티스학회 1999 대한류마티스학회지 Vol.6 No.1

Objective: Bucillamine(BUC) is a new disease-modifying anti-rheumatic drug, which is structurally similar to D-penicillamine. In type II collagen induced arthritis, BUC inhibited the proliferation of synovial lining cells. This study was designed to demonstrate whether BUC inhibits TNF-α-induced synovial cell proliferation or NF-κB activation in cultured synovial cells from patients with RA. Methods: The non-radioactive, colorimetric assay system was applied to cell proliferation assay. The activation of NF-κB was assessed by electrophoretic mobility shift assay. Results: Synovial cells proliferated in a dose-dependent manner in the presence of varying concentrations of TNF-α. The proliferative activity of synovial cells was inhibited in a dose-dependent fashion by BUC. Incubation of synovial cells with 20ng/ml TNF-α resulted in the appearance of shifted NF-κB bands. Control experiments indicated that these bands were eliminated by a 100-fold excess of unlabeled NF-κB probe, but not by a 100-fold excess of unrelated oct-1 probe. These findings represented that the binding between NF-κB and labeled probe is specific. Pretreatment with 30μg/ml BUC for 2 hours partially inhibited TNF-α-induced NF-κB activation in synovial cells. Conclusion: BUC inhibited the activation of NF-κB, which further explains the mechanism of action of this drug. Further studies on mechanism of inhibitory action of BUC on NF-κB activation are considered necessary.

치주수술후 치주포대의 사용유무에 따른 임상적 효과에 대한 비교논문

배상범,임성빈,정진형,Bae, Sang-Bum,Lim, Sung-Bin,Chung, Chin-Hyung 대한치주과학회 1999 Journal of Periodontal & Implant Science Vol.29 No.3

Since they were introduced by Ward in 1923, periodontal dressing have been routinely used following the periodontal surgery to avoid pain, infection, desensitizing teeth, inhibiting food impaction of the surgical areas, and immobilizing injured areas. Recently, however, the value of periodontal dressings and their effects on periodontal wound healing have been questioned, several authors have been reported that the use of dressing has little influence on healing following periodontal surgical procedures. In addition, there is evidence that when good flap adaptation is achieved, the use of a periodontal dressing does not add to patient comfort nor promote healing. The purpose of this study was to evaluate patient postoperative pain experience and discomfort with and without the use of periodontal dressing following periodontal surgery. Twenty-eight patients, 11 male and 17 female. were selected for this study; The age range was 31 to 56, with an average of 40.2years. Patient selection was based on existence of two bilateral sites presenting similar periodontal involvement, as determined by clinical and radiographic assessment, and requiring comparable bilateral surgical procedures. Using a splitmouth dressing. one site received a periodontal dressing while the other site did not. Pain assessment was made according to a horizontal, rating scale(0-10). After at least a two-week period, the second surgical precedure was performed using the alternate postoperative treatment. At the conclusion of the trial, a self-administered questionnaire on postoperative experience was administered, and were asked of their preference of either, dressed or undressed. The results were as follows: 1. A similar trend for mean pain and discomfort scores as assessed by patients both dressed and salinetreated procedures was evident during 7-day postsurgical period. 2. Statistical analysis of differences between the dressed side and salinetreated side with respect to pain, discomfort and patient's experiences revealed that both treatment sides behaved similarly at any postoperative day(P>0.05). 3. Considering the patient's preference, on the basis of pain and discomfort experienced, 43% preferred the saline-mouthwash and 32% preferred the dressing, 25% showing no preference for either the dressing or the saline-mouthwash. There is evidence to support the use of a periodontal dressing in retention of an apically positioned flap by preventing coronal displacement, or its use to provide additional support to stabilize a free gingival graft. However, there will always be a use for periodontal dressing although routine use of dressings may decrease because of better surgical techniques and the use of antibacterial mouth rinses.