신장이식 환자에서 HCMV 항원혈증 검사의 임상적 유용성

김탁,성흥섭,박관태,김송철,김성한,최상호,김양수,우준희,박수길,한덕종,이상오 대한감염학회 2009 감염과 화학요법 Vol.41 No.2

Background : This study was performed to determine the cut-off value and the predictability of symptomatic human cytomegalovirus (HCMV) infection according to the peak value of HCMV antigenemia assay in kidney transplant recipients. Materials and Methods : We reviewed the results of HCMV antigenemia assay (Chemicon, CA, USA) in patients who received kidney transplantation at our institution from May 2003 through May 2008, and investigated the existence and the type of HCMV infection by the medical record review. Patients who underwent the test only once during the episode or those who received ganciclovir for more than 48hrs before the test were excluded. The receiver-operator characteristic curve was drawn and the point showing maximum likelihood ratio (LR) was chosen as the cut-off value of symptomatic HCMV infection. Results : A total of 689 episodes were screened and 134 episodes were enrolled. Thirty-three (24.6%) episodes were symptomatic HCMV infection, 23 (17.2%) episodes were associated with HCMV syndrome, and 10 (7.5%) episodes were tissue-invasive diseases. The maximum LR was 7.5 (95% confidence interval, 4.014.2) and the cut-off value was 29.5 cells/200,000 WBC. The sensitivity, specificity, Positive predictive value, and negative predictive value were 66.7%, 91.1%, 71.0%, and 89.3%, respectively. Conclusions : The cut-off value of symptomatic HCMV infection by the peak value of HCMV antigenemia assay in our study was similar with previous results, although the sensitivity was relatively low.

조혈모세포이식 환자에서 침습성 진균 감염에 대한 Micafungin의 예방 효과 및 안전성

김시현,이동건,최수미,권재철,박선희,최정현,유진홍,이성은,조병식,김유진,이석,김희제,민창기,조석구,김동욱,이종욱,민우성,박종원 대한감염학회 2010 감염과 화학요법 Vol.42 No.3

Background: Micafungin, a potent inhibitor of 1,3-β-D-glucan synthase, is a novel antifungal agent of the echinocandin class. In vitro study showed that micafungin was effective against Aspergillus species as well as Candida species, but clinical data on the prophylactic efficacy against invasive fungal infections (IFIs) other than candidiasis are still lacking. Materials and Methods: We identified 60 consecutive adult hematopoietic stem cell transplantation (HSCT) recipients who received at least 3 doses of micafungin during neutropenic period. Micafungin was started as an alternative in patients who were intolerant or had adverse events (AEs) to primary prophylactic antifungal agents. We retrospectively reviewed the medical records and analyzed the efficacy and safety of micafungin for prophylaxis against IFIs. Results: The patients either had autologous (n=9) or allogeneic (n=51: 1 syngeneic, 24 sibling, 26 unrelated donor) HSCT. Itraconazole oral solution (n=58) was the most frequently used first line antifungal agent for prophylaxis and was administered for median 11 days. The most frequent cause of switch to micafungin was vomiting (n=42). The duration of neutropenia and micafungin administration was median 13 and 12 days, respectively. A successful outcome was achieved in 45 (75%) patients. Empirical antifungal therapy was initiated in 13 (22%) patients. There were 2 cases (3.3%) of breakthrough fungal infections which comprised a probable invasive pulmonary aspergillosis and a possible invasive fungal sinusitis. There was no case of invasive candidiasis. A total of 53 (88%) patients experienced at least one AE regardless of causality during micafungin administration. The most frequent AEs were hypokalemia, vomiting, diarrhea, and elevated serum aspartate aminotransferase or alanine aminotransferase. Among the aforementioned AEs, only 1 case of diarrhea could be classified as a probable relation with micafungin when causality was assessed. There was no AEs that caused discontinuation of micafungin. Conclusions: Micafungin seems to be a safe and effective agent for prophylaxis of IFIs including aspergillosis as well as candidiasis in HSCT recipients. However, further large, prospective, and randomized comparative studies are warranted for aspergillosis.

랜덤 키 분할을 이용한 모바일 RFID 사용자의 프라이버시를 보호하는 상호 인증 프로토콜

정윤수(Yoon-Su Jeong),김용태(Yong-Tae Kim),박길철(Gil-Cheol Park),이상호(Sang-Ho Lee) 한국통신학회 2011 韓國通信學會論文誌 Vol.34 No.9

이동 통신망에 RFID 기술을 접목한 모바일 RFID는 사용자 자신이 휴대한 휴대전화로 제품에 부착된 RFID태그의 식별자를 읽고, 이 식별자를 이동통신망을 통해 네트워크로 전달하여 제품에 대한 정보를 얻는 기술이다. 그러나 모바일 RFID는 기존 RFID에서 요구되어지는 보안 요구사항 중 프라이버시 문제가 여전히 존재하는 문제점이 있다. 이 논문에서는 모바일 RFID 사용자가 태그 정보를 백 엔드 서버로부터 안전하게 전달받기 위해서 초기화 과정과 상호 인증과정에서 모바일 RFID 리더와 태그가 생성한 랜덤키를 임의의 크기로 분할하여 프라이버시 보호가 필요한 태그에 대해서 모바일 RFID 리더가 매 세션마다 난수생성기에 의해 항상 다른 하부키 값을 생성함으로써 태그의 어떤 정보도 제 3자에게 제공하지 않도록 하고 있다. 성능 평가 결과 제안 프로토콜은 등록 계산량과 로그인 계산량에서 모듈러 연산을 사용하는 기존 프로토콜과 달리 일방향 해쉬 함수를 사용하여 사용자의 정보를 등록하기 때문에 MARP 기법<SUP>[7]</SUP>과 Kim 등의 기법<SUP>[12]</SUP>보다 저장 공간과 계산량에서 효율성이 높았다. Mobile RFID which integrates mobile network with RFID technique is the technique to get the information of products by transmitting the identifier through mobile network after reading the identifier of RFID tag. It attached on the equipment as the mobile phone. However, mobile RFID has the privacy-related problem among requested secure problems required from the existing RFID. In this paper, the random key created by mobile RFID reader and Tag during the inter-certificating and initialization procedure for mobile RFID users to receive tag information from backend server securely is divided into random sizes and any information on the tag which requires the protection of privacy shouldn't be provided to anyone. In performance analysis, previous protocol used modulo operation in registration and login computation. But the proposed protocol has higher efficiency in saving space and computation volume than MARP scheme<SUP>[7]</SUP> and Kim. et. al<SUP>[12]</SUP> scheme because our protocol is accomplished by mutual authentication and registering user information through one-way hash function.

편광과 위상 홀로그램을nmmmm 이용한 정보보호 시스템의 구현

김철수 경주대학교 2001 論文集 Vol.14 No.-

This thesis presents an interferometer-based optical information security system that can produce a stable decrypted image regardless of a change in the optical path length. Interference noise is a serious problem in an interferometer, because it can result in the vibration of the output image. In the proposed system, a polarizing beam splitter is substituted for the beam splitter in a Mach-Zehnder interferometer. As a result, two lights on each path are perpendicularly polarized to each other in the interferometer. Since the incoherence of the two perpendicularly polarized lights removes any interference noise, the decrypted image is stable. Accordingly, the decrypted image of the proposed system can be used as the input for another optical system, regardless of any external change in the optical path length. To encrypt an image, the original image is divided into two intensity images. Encrypted phase images are then obtained from these two images in various ways, including randomly diffusing pixels, randomly removing pixels, or the use of SA algorithm. The use of phase holograms prevents the copying of encrypted images with intensity detectors. The proposed process of encryption and decryption was computer simulated and optically evaluated, and it was verified that the proposed system can produce a stable decrypted image.

산-염기 평형 장애 진단 전문가 시스템의 설계 및 구현

김기태,유석희,황수철 중앙대학교 기술과학연구소 1989 기술과학연구소 논문집 Vol.19 No.-

In this study, we designed and implemented a diagnostic system model to process the diagnosing problem of acid-base balance disorder by means of OPS5 and LISP which are a tool and a language, respectively for developing Al systems. The implemented knowledge base system consists of three kind of the knowldege : one analytic knowledge of blood test, two diagnostic knowledges obtained by etiologies and symptoms. The knowledge representation and the inference mechanism for diagnosis were implemented by OPS5, and all input / output was processed by a menu-driven method in support of the window functions of LISP.

비파괴 검사를 위한 PZT 탐촉자의 제작 및 특성에 관한 연구

김철수,정규원,송준태 성균관대학교 1998 학술회의지원논문목록집 Vol.1998 No.-

Ultrasonic probes of 400kHz, 1MHz, 3MHz were fabricated using P2T 5A plates Epoxy was used for backing layer materials on the plates. Nondestructive Test was carried using these probes. Pulse lobe width of impulse response was reduced 15.4% compare 1MHz with 400MHz and 96.6% compare 3MHz with 400kHz. The attenuation in aluminum was 2.05[dB/m] at 400kHz, 4.91[dB/m] at 1MHz, 7.35[dB/m] at 3MHz. Hole detection error of the first hole was 22.4% at 1MHz, 9.6% at 3MHz. The second hole 11.6% at 1MHz, 4.7% at 3MHz. In the result of experiment of the hole detection errot and resolution., 3MHz probe was the best among them.

반복 알고리듬에 근거한 광 상관기를 이용한 영상 보안 시스템

김철수 경주대학교 정보전자기술연구소 2003 情報電子技術論叢 Vol.2 No.-

In this paper, a practical image security system using 4-f Optical Correlator based on the SA algorithm is proposed. In the encrypting process, we would generate encrypted image and key image with binary phase components using iterative SA algorithm. In the decrypting process, we can get a correlation results of the encrypted and key images using 4-f correlator system. In the proposed method, the encrypted and key images consisted of binary phase components. So, it is easy to implement optical security system using the proposed technique. And if we fix the encrypted image in the optical security system and change the key image, we get different images, so it is possible to apply to the distinguished authorization system using different key images. Computer simulations show that despite the binary phase components, the quality of the decrypted images are very good in terms of mean squared error.

茵蔯淸肝場의 B型 및 C型 간염 바이러스에 대한 抗 바이러스 效果

김수성,김기열,윤철호,서운교,김종대,정지천 동국대학교 한의학연구소 1999 東國韓醫學硏究所論文集 Vol.8 No.1

우리나라와 같이 B형 간염 바이러스의 유병율이 높은 지역에서는 B형 간염 바이러스 뿐만 아니라 HCV에 대한 항 바이러스 효과도 동시에 시행함이 유용할 것으로 사료되었다. 본 연구에서는 茵蔯淸肝湯을 이용하여 B형 간염 바이러스에 대한 抗 바이러스 효과를 PCR을 이용하여 HBV의 DNA를 검색하였다. 茵蔯淸肝湯이 처리된 처리군의 경우 대조군에 비하여 농도 의존적으로 B형 간염 바이러스의 표면항원 생산을 억제하였고, PCR을 이용하여 증폭한 경우에도 증폭된 DNA의 양은 감소하였다. 또한 C형 간염 바이러스에 대한 抗 바이러스효과를 검색하기 위하여 복제에 필수적인 단백질인 HCV helicase의 ATPase에 대한 활성 억제 효과를 조사하였다. 茵蔯淸肝湯이 HCV helicase의 ATPase 활성을 억제하는 효과가 있음을 확인한 후 dose-respond에 따른 실험을 수행하여 HCV helicase의 ATPase 활성을 억제함으로써 탈인산화 되지 않은 ATP의 양을 이용하여 PSL로 분석한 결과 茵蔯淸肝湯이 HCV helicase의 ATPase 기능에 대한 억제효과가 우수함이 확인되었다. 이상의 결과로 보아 茵蔯淸肝湯이 B형 및 C형 간염 치료에 동시에 응용될 수 있을것으로 사료된다. For the purpose of investigate the inhibition effects of Injinchunggantang on Hepatitis and C Virus. The inhibition experiments were as follows : 1. The inhibition effects of Hepatitis B surface antigen production was remarkably increased in the pretreated group of Injinchunggantang compared with control group. 2. Amplified PCR products of HBV-DNA in culture media was considerably decreased in the pretreated group of Injinchunggantang compared with control group. 3. Results of ATP quantitation and ATPase inhibition percent was increased pretreated group of Injinchunggantang. Also ATPase activity of HCV helicase inhibition assay was increased with a dose dependent manner. These results may suggest that Injinchunggantang will have the inhibition effects of Hepatitis B and C Virus.

시각 암호화와 가상 위상 영상을 이용한 광학적 보안 시스템

김철수 경주대학교 2003 論文集 Vol.16 No.-

In this paper, we proposed an optical security system using visual cryptography and virtual phase images. In encryption process, original image is shared out virtual image, random iamge, and decryption key image, and they are phase modulated. We multiply the phase virtual image with the phase random image, and then multiply with each complex image which has its magnitude with constant value. Finally, the encryption cards are made by Fourier transforming the multiplicated images. It is possible to protect information of the orignal image because the cards have not any information of the original image. To reconstruct the original image from the encrypted card images, Encrypted card images are put on the paths of Mach-Zehnder interferometer to be summed the card images. The summed image is inverse Fourier transformed by Fourier lens, and multiplied with phase decryption key and then interferenced with reference beam again. Finally, the original image is recovered in the form of intensity on the CCD plane. Computer simulations show a good performance of the proposed optical security system.

원예치료가 만성정신분열증 환자의 자아존중감 및 사회성 향상에 미치는 영향

손기철,엄수진,김수연,송종은,백기엽 충북대학교 첨단원예기술개발연구센터 2000 연구보고서 Vol.5 No.-

만성정신분열증 환자들은 장기간의 치료를 필요로 하고, 지금까지는 대부분의 환자들이 약물치료나 전통적인 정신치료에만 의존해왔다. 최근에는 정신분열증 환자치료에 있어서 여러 가지 사회 재활 프로그램이 도입되고 있는 실정이나 원예치료프로그램의 적용사례는 미비한 실정이다. 이에 본 연구는 원예치료가 만성정신분열증 환자의 자아존중감 및 사회성 향상에 미치는 효과를 알아보기 위하여 음성 꽃동네 정신분열증 환자 남녀 대조군 20명, 치료군 남녀 25명을 선정하여 실험을 실시하였다. 대조군 20명에게는 원예치료를 실시하지 않았으나, 치료군 25명에게는 주 2회씩 2000년 4월 13일부터 9월 7일까지 원예치료를 실시하였다. 치료효과 검증을 위해 원예활동 평가표(evaluation of horticultural activity), 사회행동척도(social behavior scale), 자아존중감척도(self-esteem Scale), 인간관계측정지, 간이정신건강진단지(SCL-90-R) 등을 치료 전후로 시행하여 비교하였다. 자아존중감과 인간관계측정지에서는 대조군에서는 유의한 결과가 보이지 않은 반면, 치료군에서는 향상된 결과를 볼 수 있었다. 사회행동척도에서는 언어적인면보다 비언어적인면, 대화의 내용에서 치료군만 유의하게 향상된 결과를 보였다. 간이정신건강진단지 평가는 불안, 우울, 대인예민성 부분에서 역시 치료군만 유의하게 호전된 효과를 볼 수 있었다. 또한 신체화, 강박증, 적대감, 공포불안, 편집증 등이 호전된 것으로 보여졌으나 통계적으로 유의한 차이는 나타나지 않았다. 원예활동평가에서는 참여성과 자아개념 및 주체성에서 유의한 차이를 볼 수 있었다. 따라서 원예치료프로그램은 우울ㆍ폐쇄적인 대인관계를 보이는 정신분열증 환자들에게 심리ㆍ정서면과 사회성 향상에 효과적이라 판단된다. 또한 원예치료프로그램을 치료적인 목적뿐만 아니라 직업재활의 한 방면으로 이용가능 할 것이라 판단된다.