충청지역에서 발생한 쭈쭈가무시병의 임상상, 원인균의 혈청형 및 혈청역학적 연구

김선영,김윤성,박장규,윤태영,강재승,송인숙,최명식,최인학,차창룡,이우곤,박종우,이증훈,장우현,유영해,윤광혁,송계용 대한감염학회 1989 감염 Vol.21 No.2

From September to december 1987, eighty-six cases of tsutsugamushi disease were diagnosed by indirect immunofluorecent test or by isolating the causative agent in Chungcheung area. Their clinical features and patterns of antibody response to R. tsutsugamushi were analyzed. For the indenfication of prevalent antigenic types of R. tsutsugamushi in Chungcheung area, twenty-seven strains isolated were tested by indirect immunofluorescent test. To assess the extent of exposure to R.tsutsugamushi of a general population in Korea, the prevalence of antibody was investigated in 6,572 sera obtained from the residents of Chungcheung area by indirect immunofluorescent test. The female patients slightly outnumbered the male patients. More cases (68%) were older than 40 years of age. The epidemic peaked in October. The mean incubation period estimated was about 8 days. The major clinical features were fever and chill, headache, rash, eschar, and lymphadenopathy. Increased serm transaminase was the most singificant laboratory findings. Abnormalities in the chest roentgenography were often observed. The antibody titer rose rapidly 5 days after the onset, reached its peak at 20 days (1:640), and then declined agradually until 7 months(1:20). The seroype of 23 out of the 27 isolates wase found to be karp, one was Gilliam, and 3 isolates could not be classified by using polyclonal mouse hyperimmune sera. The prevalence of antibody to R.tsutsugamushi in the residents of Chungcheung area was 4.8%. The prevalence of antibody was higher in the female than in the male. The prevalence was higher in the residents of age above 40 years than below 40 years, and was the lowest in the children less than 10 years of age. Of the 318 positive sera from normal residents, only 2 sera showed the titers higher than 1:80.

Nanostructured glycan architecture is important in the inhibition of influenza A virus infection

Kwon, Seok-Joon,Na, Dong Hee,Kwak, Jong Hwan,Douaisi, Marc,Zhang, Fuming,Park, Eun Ji,Park, Jong-Hwan,Youn, Hana,Song, Chang-Seon,Kane, Ravi S.,Dordick, Jonathan S.,Lee, Kyung Bok,Linhardt, Robert J. Nature Publishing Group, a division of Macmillan P 2017 Nature nanotechnology Vol.12 No.1

<P>Rapid change(1) and zoonotic transmission to humans(2) have enhanced the virulence of the influenza A virus (IAV)(3). Neutralizing antibodies fail to provide lasting protection from seasonal epidemics(1),(4). Furthermore, the effectiveness of anti influenza neuraminidase inhibitors has declined because of drug resistances. Drugs that can block viral attachment and cell entry independent of antigenic evolution or drug resistance might address these problems. We show that multivalent 6'-sialyllactose-polyamidoamine (6SL-PAMAM) conjugates, when designed to have well-defined ligand valencies and spacings, can effectively inhibit IAV infection. Generation 4 (G4) 6SL-PAMAM conjugates with a spacing of around 3 nm between 6SL ligands (S3-G4) showed the strongest binding to a hemagglutinin trimer (dissociation constant of 1.6 x 10(-7) M) and afforded the best inhibition of H1N1 infection. S3-G4 conjugates were resistant to hydrolysis by H1N1 neuraminidase. These conjugates protected 75% of mice from a lethal challenge with H1N1 and prevented weight loss in infected animals. The structure-based design of multivalent nanomaterials, involving modulation of nanoscale backbone structures and number and spacing between ligands, resulted in optimal inhibition of IAV infection. This approach may be broadly applicable for designing effective and enduring therapeutic protection against human or avian influenza viruses.</P>

An emerging recombinant cluster of nephropathogenic strains of avian infectious bronchitis virus in Korea

Lim, T.H.,Lee, H.J.,Lee, D.H.,Lee, Y.N.,Park, J.K.,Youn, H.N.,Kim, M.S.,Lee, J.B.,Park, S.Y.,Choi, I.S.,Song, C.S. Elsevier Science 2011 Infection, genetics and evolution Vol.11 No.3

The infectious bronchitis virus (IBV) is continuously evolving through point mutation and recombination of their genome, subsequently the emergence of IBV variants complicates disease control. The objective of this study was to investigate genetic characterization of new IBV variants isolated from commercial chicken flocks in Korea collected between 2005 and 2010. Phylogenetic analysis revealed that all new IBV isolates belonged to Korean group II (K-II), which included the nephropathogenic IBV strains. However, the isolates formed a new gene cluster that was distinguished from the two distinct K-II subgroups (KM91-like and QX-like). Recombination events were identified in the S1 gene, with their putative parental strains being the KM91-like or QX-like subgroup. In addition, two crossover sites were observed in the S1 gene of IBV isolates. These results suggest that natural genetic recombination between heterologous strains classified into different genetic groups has occurred and may have caused the emergence of new IBV strains. This finding provides important information on IBV evolution and is essential for the effective control of IB in Korea.

자동차용 엔진 냉각 시스템의 이론적 해석

윤종갑,송승훈,원성필 울산대학교 2001 공학연구논문집 Vol.32 No.2

자동차의 엔진 냉각 시스템은 저 연비, 공해 감소, 엔진 수명 향상을 포함한 엔진의 성능 향상과 밀접한 관계가 있으나 설계 시 냉각 시스템에서 각 요소의 성능과 복잡한 반응때문에 시험 차량에 의한 하드웨어 실험은 많은 비용과 시간이 소비되고 여러 조건에 의한 시스템의 반응을 분명히 이해하기 힘들기 때문에 컴퓨터 시뮬레이션은 설계자들에게 값싸고, 효과적인 설계와 광범위한 조건에서 자동차 엔진 냉각 시스템의 설계, 개발, 최적화를 할 수 있는 분석 도구이다. 본 연구는 냉각 시스템 구성 요소인 엔진, 라디에이터, 히터, 서모스탯, 워터 펌프, 냉각 팬 등을 모델링하고 수치 해석을 통하여 자동차의 시동 시, 정속 주행 시, 시내 주행 시, 등판 주행 시 엔진 냉각 시스템의 열적 성능을 컴퓨터 프로그램으로 예측 가능하게 하고 나아가 엔진 냉각 시스템의 구성 요소의 설계 변화와 시스템의 배열 변화를 가능하게 함으로 복잡한 엔진 냉각 시스템의 성능 향상이 가능한 시뮬레이션 프로그램을 개발하였다. In this work, it has been predicted the thermal performance of the engine cooling system in cases of stationary mode, constant speed mode, city-drive mode, and hill-climb mode by theoretical modeling of each component and numerical analysis. The modelling components are engine, radiator, heater, thermostat, water-pump, and cooling-fan. And also it has been developed the simulation program that can be used in case of design and system configuration changes. The comparison has not been made to verify the results of this work with experimental data, but the overall tendencies were agreed well with those of actual situation in four modes

Tunable optofluidic birefringent lens

Wee, D.,Hwang, S. H.,Song, Y. S.,Youn, J. R. The Royal Society of Chemistry 2016 Soft matter Vol.12 No.17

<P>An optofluidic birefringent lens is demonstrated using hydrodynamic liquid-liquid (L-2) interfaces in a microchannel. The L-2 lens comprises a nematic liquid crystal (NLC) phase and an optically isotropic phase for the main stream and the surrounding sub-stream, respectively. When the optofluidic device is subjected to a sufficiently strong electric field perpendicular to the flow direction, NLCs are allowed to orient along the external field rather than the flow direction overcoming fluidic viscous stress. The characteristics of the optofluidic birefringence lens are investigated by experimental and numerical analyses. The difference between the refractive indices of the main stream and the sub-stream changes according to the polarization direction of incident light, which determines the optical behaviour of the lens. The incidence of s-polarized light leads to a short focal point, while p-polarized light has a relatively long focal distance from the same L-2 interface. The curvatures and focal lengths of the lens are successfully evaluated by a hydrodynamic theory of NLCs and a simple ray-tracing model.</P>

Alzheimer's Disease Transgenic Mice Expressing NSE/APPsw

Dae Y. Hwang,Jung S. Cho,Tae S. Kang,Jin H. Hwang,Chae H. Lim,Su H. Lee,Hwa J. Lim,Sae H. Min,Su J Seo,Youn S. Song,Yong K. Kim 한국실험동물학회 2003 한국실험동물학회 학술발표대회 논문집 Vol.2003 No.-

Interpretation of Ostwald ripening of catalytic nanoparticles based on the radial breathing mode in single-walled carbon nanotubes

Song, W.,Hwan Kim, S.,Sung Jung, D.,Kim, Y.,Youn Kim, S.,An, K.S.,Park, C.Y. North-Holland 2014 Physica E, Low-dimensional systems & nanostructure Vol.64 No.-

Catalytic nanoparticle (NP) size is the crucial factor that determines carbon nanotube (CNT) diameter. Therefore, we explored the Ostwald ripening phenomenon of catalytic NPs from the radial breathing modes in resonant Raman spectra of synthesized single-walled CNTs (SWCNTs). SWCNTs were synthesized using chemically derived monodisperse Fe oxide catalytic NPs by a conventional thermal chemical vapor deposition system. The density of the NPs was manipulated by simply adjusting the spin-coating speed and cycle. The diameter distribution and tube type (SWCNTs or multi-walled CNTs) were thereby determined, which can be understood by density-dependent Ostwald ripening of the NPs. As a result, the diameter-selective growth of SWCNTs was successfully achieved, which will be useful for SWCNTs-based electronic applications.

Development of a new tri-block copolymer with a functional end and its feasibility for treatment of metastatic breast cancer

Song, H.T.,Hoang, N.H.,Yun, J.M.,Park, Y.J.,Song, E.H.,Lee, E.S.,Youn, Y.S.,Oh, K.T. Elsevier 2016 Colloids and surfaces Biointerfaces Vol.144 No.-

<P>We have developed nanomedicine vehicle based on a biocompatible tri-block copolymer, poly(ethylene glycol)-block-poly(lactic acid)-block-poly(ethylene glycol) (PEG-PLA-PEG) by simple approach without toxic linker to escalate therapeutic efficacy of anticancer agent by enhanced targeting to metastasized breast cancers. The synthesized ABA type copolymer had a low polydispersity index and formed small, highly stable spherical micelles. Furthermore, a functional group at the end site of the copolymer can be decorated with imaging agents and targeting moieties. The doxorubicin loaded micelles (DLM) showed higher drug-loading capacity, faster drug release, and better cell toxicity compared to those using di-block copolymers. DLM efficiently delivered to the metastatic breast cancers in brain and bone and suppressed growing of metastasis. In demonstration of treating metastasized animal model, we present a tri-block copolymer as. a potential nanomedicine vehicle to efficiently deliver anticancer drug and to effectively treat metastatic breast cancer. Crown Copyright (C) 2016 Published by Elsevier B.V. All rights reserved.</P>

Increased efficacy of inactivated vaccine candidates prepared with Salmonella enterica serovar Typhimurium strains of predominant genotypes in ducks

Youn, S.Y.,Kwon, Y.K.,Song, C.S.,Lee, H.J.,Jeong, O.M.,Choi, B.K.,Jung, S.C.,Kang, M.S. Elsevier 2016 Poultry science Vol.95 No.8

<P>Salmonella enterica serovar Typhimurium has been a major causative agent of food-borne human disease, mainly due to consumption of contaminated food animal products. In particular, ducks serve as a reservoir of serovar Typhimurium, and are one of the common sources of human infection. To prevent infection of ducks, and therefore minimize human infection, it is critical to control the persistent epidemic strains in ducks. Here, we analyzed the genetic diversity and virulence of serovar Typhimurium isolates from ducks in Korea to identify the predominant strains that might be used as efficient vaccine candidates for ducks. Among the isolates, 2 representative isolates (ST26 and ST76) of predominant genotypes were selected as vaccine strains on the basis of genotypic analysis by pulsed-field gel electrophoresis and DNA microarrays. Two-week-old ducks were then injected intramuscularly with inactivated vaccine candidates prepared using ST26 or ST76 (10(8) cfu/0.5 mL/duck or 10(9) cfu/0.5 mL/duck), and oral challenge with a highly virulent serovar Typhimurium strain (10(9) cfu/0.5 mL/duck) was carried out 2 wk later. Shedding of the challenge strain was significantly decreased in group 2 after vaccination. The antibody levels by enzyme-linked immunosorbent assay in all vaccinated groups were enhanced significantly (P < 0.05) compared to the unvaccinated control group. Overall, vaccination with ST26 or ST76 reduced bacterial shedding and colonization in internal organs, and induced elevated antibody response. In particular, serovar Typhimurium ST26 (10(8) cfu/0.5 mL/duck) was the most effective vaccine candidate, which can provide efficient protection against serovar Typhimurium in ducks with higher effectiveness compared to a commercial vaccine currently used worldwide.</P>

On-chip Smart Functions for Efficiency Enhancement of MMIC Power Amplifiers for W-CDMA Handset Applications

Youn S. Noh,Ji H. Kim,Joon H. Kim,Song G. Kim,Chul S. Park 대한전자공학회 2003 Journal of semiconductor technology and science Vol.3 No.1