• Title/Summary/Keyword: K-6

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Synthesis of 1-[3-(Propylthio)butyryl]-2,6,6-trimethylcyclohexene (1-[3-(프로필티오) 부티릴]-2,6,6-트리메틸시클로헥센의 합성)

  • Jong Hoon Oh;Kyong Tae Kim;Yong Tae Kim
    • Journal of the Korean Chemical Society
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    • v.29 no.3
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    • pp.311-318
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    • 1985
  • 1-[3-(Propylthio)butyryl]-2,6,6-trimethylcyclohexene (18) was synthesized from the reaction of 2,6,6-trimethylcyclohex-l-en-1-yllithium (9) with 3-propylthiobutyraldehyde (16). This method will be employed to prepare 1-[3-(methylthio)butyryl]-2,6,6-trimethylcyclohexene (1) which is known as one of the powerful flavors and fragrances.

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Effect of disulphide bond position on salt resistance and LPS-neutralizing activity of α-helical homo-dimeric model antimicrobial peptides

  • Nan, Yong-Hai;Shin, Song-Yub
    • BMB Reports
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    • v.44 no.11
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    • pp.747-752
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    • 2011
  • To investigate the effects of disulphide bond position on the salt resistance and lipopolysaccharide (LPS)-neutralizing activity of ${\alpha}$-helical homo-dimeric antimicrobial peptides (AMPs), we synthesized an ${\alpha}$-helical model peptide ($K_6L_4W_1$) and its homo-dimeric peptides (di-$K_6L_4W_1$-N, di-$K_6L_4W_1$-M, and di-$K_6L_4W_1$-C) with a disulphide bond at the N-terminus, the central position, and the C-terminus of the molecules, respectively. Unlike $K_6L_4W_1$ and di-$K_6L_4W_1$-M, the antimicrobial activity of di-$K_6L_4W_1$-N and di-$K_6L_4W_1$-C was unaffected by 150 mM NaCl. Both di-$K_6L_4W_1$-N and di-$K_6L_4W_1$-C caused much greater inhibitory effects on nitric oxide (NO) release in LPS-induced mouse macrophage RAW 264.7 cells, compared to di-$K_6L_4W_1$-M. Taken together, our results indicate that the presence of a disulphide bond at the N- or C-terminus of the molecule, rather than at the central position, is more effective when designing salt-resistant ${\alpha}$-helical homo-dimeric AMPs with potent antimicrobial and LPS-neutralizing activities.

Follow-Up Study of 6-Month Short Course Chemotherapy for Pulmonary Tuberculosis with 2SKHRZ/4HRZ (폐결핵에서 6개월 단기 항결핵 화학요법의 추구검사)

  • Koh, Hyung Ki;Kang, Yun Jung;Lim, Seong Yong;Shin, Jong Wook;Choi, Jae Sun;Yoo, Ji Hoon;Park, In Won;Choi, Byoung Whui;Hue, Sung Ho;Seo, Seung Chun
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.6
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    • pp.852-861
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    • 1996
  • Background : Many clinicians have experienced the difficulty of decision on termination of antituberculosis chemotherapy after the 6th month due to relapse of disease. There is still controversy in the effect of 2S(K)HRZ/4HRZ 6-month short course chemotherapy including pyrazinamide for 6 months in patiems with pulmonary tuberculosis. And there is no long term follow-up study of 6-month short course chemotherapy for pulmonary tuberculosis in korea. So we had performed the study to find the result of 6-month antituberculosis chemotherapy for 4 years. Method : We studied prospectively the effect of 2S(K)HRZ/4HRZ in one hundred-fifty patients with pulmonary tuberculosis and followed up fifty-nine patients for more than 1 year to 4 years after the completion of 6-month short course therapy. Results : 1) Out of one hundred-fifty patients, seventy-two patients(48%) completed the prescribed 6-month chemotherapy. Sixty-eight patients(45.3%) have experienced premature discontinuation and the most common cause of premature discontinuation was drop-out against advice(thirty-six patients, 24%). Ten patients(6.7%) were treated beyond the 6 months mainly due to irregular treatment. 2) Fifty-nine patients(81.9%) among seventy-two patients with completed treatment have been followed up for more than 1 year and 32 patients(44.4%) for more than 4 years. There was three relapse patients of whom two patients have experienced relapse of pulmonary tuberculosis within 1 year after the termination of chemotherapy. 3) Among one hundred-thirty-four patients who have been assessible for more than two months of chemotherapy, including the patients who experienced within 2 months, there were eighty-two patients(61.2%) who have experienced adverse reactions and the treatment regimen was changed only in thirteen patients(9.7%). The most frequent cause of adverse reactions was arthralgia and/or hyperuricemia, which had occurred in 33 patients(24.6%). Conclusion : In a university hospital in Korea, 6-month shot course chemotherapy of 2S(K)HRZ/4HRZ had unnegligible relapses and premature discontinuation. Therefore, change of the regimen might be carefully considered by drug susceptibility results. Close monitoring of patients, retrial of sputum exam and radiologic evaluation during treatment might be required in the endemic area of drug resistant strains like in Korea. Further study about the effect of 6-month short course chemotherapy including pyrazinamide for 6-month might be needed.

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A Implementation Method of mixed IPv4/IPv6 Network for Testing Security Vulnerability (보안취약점 테스트를 위한 IPv4/IPv6 혼재 네트워크 구축 방법)

  • Kim Jeong-Wook;Mun Gil-Jong;Kim Yong-Min;Noh Bong-Nam
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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    • 2006.06a
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    • pp.477-480
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    • 2006
  • IPv6는 IPv4의 주소 부족을 해결하기 위해 1998년 IETF에서 표준화된 프로토콜이다. 현재 IPv4가 수축으로 되어 있는 인터넷을 동시에 IPv6로 전환하는 것은 불가능하므로 IPv4/IPv6 혼재네트워크를 거쳐 IPv6 순수 망으로 전환될 것이다. 본 논문에서는 혼재네트워크에서 IPv4 망과 IPv6 망간의 통신을 가능하게 해주는 IPv6 전환 메커니즘 중 터널링 방식에 대해 기술하고, 보안 취약성을 테스트하기 위해 동일한 보안 취약성에 대해 각각 IPv4 패킷, IPv6 패킷, 터널링된 패킷을 캡쳐할 수 있는 구축방안을 제안한다. 제안된 방식은 IPv4, IPv6, 터널링 패킷에 대한 분석이 가능하므로 IPv6 지원을 계획하는 침입탐지, 침입차단 시스템에 활용이 가능하다.

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A Security Vulnerability in IPv6 Native Network and Mixed IPv4/IPv6 Network (IPv6 순수망과 IPv4/IPv6 혼재망의 보안 취약점)

  • Yi Young-Soo;Park Nam-Youl;Kim Yong-Min;Noh Bong-Nam
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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    • 2006.06a
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    • pp.340-343
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    • 2006
  • IPv6는 차세대 네트워크를 구축하기 위한 가장 핵심적인 기술로써, 풍부한 주소공간과 이동성 지원, 보안기능 강화 등 IPv4에 비해 많은 이점을 지니고 있다. 또한 IPv4의 주소 고갈 문제를 해결하기 위해 IPv6로의 전환이 당연시 되고 있으나 IPv4/IPv6 혼재망이 과도기적인 입장에서 대안이 될 수 있다. 그러나 IPv4/IPv6 혼재망과 IPv6망은 IPv4에서와 마찬가지로 프로토콜 기능상의 많은 문제점을 안고 있다. 본 논문에서는 IPv6망 및 IPv4/IPv6 혼재 네트워크상에서의 보안 취약점과 실험 결과를 기술하였다.

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Developing Equipment to Detect the Deterioration Status of 6.6kV Power Cables in Operation at Power Station (발전소에서 운전 중인 활성 6.6kV 전력 케이블의 고장상태를 파악하는 장치의 개발)

  • Um, Kee-Hong;Lee, Kwan-Woo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.4
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    • pp.197-203
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    • 2014
  • The technology to predict and prevent an accident of the cable system in power station is required. The techniques of inactivated diagnosis, partial discharge and $tan{\delta}$, have been adopted to diagnoze the operating characteristics of cables, but it is not so easy to find out problems in cables in an inactive state before the cable accident happens. In this paper, we did a research on the 6.6kV high-power cables, installed at Korean Western Power Station Co., Ltd. in order to diagonize the cables, playing a major role at the station. We have developed an equipment to measure an insulation resistance based on the temperature and current of the cable. By installing the system in a power station, we could find abnormal status for evaluation of the lifetime. In the short term, by analyzing the data, we apply the research result to the diagnosis and evaluation of the 6.6kV power cables. In the long run, however, we plan to reduce the cost of the installation and operation of cable systems at power stations.

Epigenetic role of nuclear S6K1 in early adipogenesis

  • Yi, Sang Ah;Han, Jihoon;Han, Jeung-Whan
    • BMB Reports
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    • v.49 no.8
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    • pp.401-402
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    • 2016
  • S6K1 is a key regulator of cell growth, cell size, and metabolism. Although the role of cytosolic S6K1 in cellular processes is well established, the function of S6K1 in the nucleus remains poorly understood. Our recent study has revealed that S6K1 is translocated into the nucleus upon adipogenic stimulus where it directly binds to and phosphorylates H2B at serine 36. Such phosphorylation promotes EZH2 recruitment and subsequent histone H3K27 trimethylation on the promoter of its target genes including Wnt6, Wnt10a, and Wnt10b, leading to repression of their expression. S6K1-mediated suppression of Wnt genes facilitates adipogenic differentiation through the expression of adipogenic transcription factors PPARγ and Cebpa. White adipose tissues from S6K1-deficient mice consistently exhibit marked reduction in H2BS36 phosphorylation (H2BS36p) and H3K27 trimethylation (H3K27me3), leading to enhanced expression of Wnt genes. In addition, expression levels of H2BS36p and H3K27me3 are highly elevated in white adipose tissues from mice fed on high-fat diet or from obese humans. These findings describe a novel role of S6K1 as a transcriptional regulator controlling an epigenetic network initiated by phosphorylation of H2B and trimethylation of H3, thus shutting off Wnt gene expression in early adipogenesis.

Comparison of Properties of Polyclonal Anti-N-Acetylchitooligosaccharides and Anti-Chitooligosaccharides Antibodies Produced for ELISA

  • Shim, Youn-Young;Shon, Dong-Hwa;Kwak, Bo-Yeon;Yu, Jae-Hoon;Chee, Kew-Mahn
    • Journal of Microbiology and Biotechnology
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    • v.14 no.4
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    • pp.686-692
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    • 2004
  • To develop the enzyme-linked immunosorbent assay (ELISA) for the analysis of N-acetylehitooligosaccharides (NACOS) and chitooligosaccharides (COS), specific antibodies (Abs) were produced, and their properties were compared. N-acetylehitohexaose (NACOS6), chitohexaose (COS6), and COS mixture (COSM) conjugated to bovine serum albumin (BSA) were used to immunize rabbits. By the use of specific Abs and NACOS6-horseradish peroxidase (HRP), COS6-HRP, and COSM-HRP conjugates, competitive direct ELISA (cdELISA) was developed. The detection limits of NACOS6 by the anti-NACOS6 Ab and COS6 by the anti-COS6 and the anti-COSM Abs in the cdELISAs were about 0.2, 2, ana 2 ng/ml (ppb), respectively. In the cdELISA, the anti-NACOS6 Ab was found to recognize NACOS3-NACOS6, but not N-acetyl-D-glucosamine (GlcNAc), NACOS2, and COSs; the anti-COS6 Ab recognized COS2-COS6 and COSM, but not glucosamine (GlcN) and NACOSs. The recognition pattern of the anti-COSM Ab was almost the same as that of the anti- COS6 Ab, except that the former recognized COS2 and COS3 slightly better than the latter.

IPSec in co-existence of IPv4 and IPv6 (IPv4와 IPv6가 혼재하는 상황에서의 IPSec)

  • Kang Jimyung;Jeong Jiwoong;Kim Chong-kwon;Shin Seong-Jun;Ahn Joung-Chul
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.11a
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    • pp.466-468
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    • 2005
  • 현재 사용되는 인터넷은 IPv4를 기반으로 하고 있다. 그러나 IPv4 주소의 부족을 예상하면서 128bit의 주소를 사용하는 IPv6이 제안되었다. IPv6로 네트워크가 이동해 가기 위해서는 IPv4와 IPv6이 공존하는 과도기적 상황을 필수적으로 겪어야 한다. 즉 IPv6과 IPv4와의 통신이 가능해져야지만, IPv6의 도래가 가능할 것이다. 이러한 상황을 고려한 통신 방안들이 1ETF에서 제안되었다. 하지만 이러한 방안들은 네트워크의 보안이 거의 고려되지 못하였다. 본 논문에서는 IPv4와 IPv6이 공존하는 상황에서 차세대 보안 기술의 선두격인 IPSec을 사용할 때 발생할 수 있는 보안 문제들에 대해 분석하고, 이러한 네트워크 보안을 고려한 IPv4와 IPv6의 통신 프레임 워크를 제시한다.

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Phytochemical Constituents from Salvia plebeia

  • Lee, Ghang Tai;Duan, Chao Hui;Lee, Jung-Noh;Lee, Kwang-Sik;Hong, Jin-Tae;Lee, Kun-Kook
    • Natural Product Sciences
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    • v.16 no.4
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    • pp.207-210
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    • 2010
  • Phytochemical investigation of Salvia plebeia resulted in the isolation of nine compounds. Their structures were determined to be 6-methoxynaringenin (1), 6-methoxynaringenin-7-O-$\beta$-D-glucoside (2), hispidulin (3), homoplantaginin (4), nepetin (5), nepitrin (6), 6-hydroxyluteolin (7), caffeic acid (8) and rosmarinic acid (9) by spectroscopic analyses. 6-Methoxynaringenin (1), 6-hydroxyluteolin (7) and rosmarinic acid (9) were isolated from this plant for the first time.