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      • KCI등재후보

        Hepatic Cirrhosis Occurring in a Young Woodchuck(Marmota monax) Due to Vertical Transmission of Woodchuck Hepatitis Virus(WHV)

        Kyu-shik Jeong,정원일,Jae-yong Chung,Mi-young An,Chae-yong Jung,Gyoung-jae Lee,Jong-soo Kang,Byeong-cheol Kang,Young-heun Jee,Bruce H Williams,Young-oh Kwon,Da-hee Jeong 대한수의학회 2003 Journal of Veterinary Science Vol.4 No.2

        Cirrhosis Occurring in a Young Woodchuck (Marmota monax) Due to Vertical Transmission of Woodchuck Hepatitis Virus (WHV)Da-hee Jeong, Won-il Jeong, Jae-yong Chung, Mi-young An, Chae-yong Jung, Gyoung-jae Lee1, Jong-soo Kang1, Byeong-cheol Kang2, Young-heun Jee3, Bruce H Williams4, Young-oh Kwon5 and Kyu-shik Jeong*College of Veterinary Medicine, Kyungpook National University, Daegu 702-701, Korea1Shinwon Scientific Co., LTD, Research Institute, Suwon, Korea2Clinical Research Institute, Seoul National University, Seoul 110-744, Korea3College of Veterinary Medicine, Jeju National University, Jeju 690-756, Korea

      • 노화가 인체 중간엽 줄기세포로부터 조골세포로의 증식 및 분화에 미치는 영향

        백기현,태현정,오기원,이원영,조정기,권순용,강무일,차봉연,이광우,손호영,강성구,김춘추 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.3

        연구배경: 일반적으로 골다공증과 연관된 위험인자로는 연령, 폐경, 약물, 불충분한 칼슘섭취, 만성질환 및 운동부족 등이 있는데, 특히 노화가 진행할수록 골밀도가 감소하는 것은 잘 알려져 있다. 노화와 관련하여 진행되는 골소실은 조골세포 및 전구조골세포의 기능적 결핍에 의한 골형성의 감소가 주요한 요인으로 여겨지고 있다. 그 동안 연령이 조골모 세포의 양과 조골모 세포로부터 성숙조골세포로의 분화 및 증식에 미치는 영향에 대한 일부 보고들이 있었으나 아직 일치된 견해는 없는 형편이다. 방법: 다양한 연령의 사람으로부터 골수를 채취, 중간엽 줄기세포가 포함된 단핵세포를 분리한 후 조골세포로 분화하기 좋은 조건하에서 배양하였다. 대상군은다시 젊은군과 노령군으로 구분하여 다양한 변수를 비교 분석하였다. 일차배양에서는 CFU-F를 계수하여 골수내 중간엽 줄기세포의 수를 추산하였고, 칼슘측정을 통하여 기질의 무기화 정도를 비교하였다. 계대배양후 이차배양에서는 시기별로 알카리성 포스파타제 활성도를 측정하고 오스테오칼신 mRNA의 발현을 관찰하여 젊은군과 노령군 사이의 증식능 차이를 비교하였다. 또한 이차배양 시기별로 MTT 측정을 하여 양군간에 증식능 차이가 있는지 알아보았다. 결과: 1. 일차배양 15일째에 평균 CFU-F의 수는 젊은군에서 유의하게 많았다(젊은군 148.3±28.9, 노령군 54.3±9.1, p=0.02). CFU-F의 평균면적은 젊은군에서 넓은 경향을 보였으나 통계적으로 유의하지는 않았다. 2. 일차배양 17일 경과 후 양군간에 기질 칼슘 침착정도는 유의한 차이를 보이지 않았다(젊은군 103.6±50.6, 노령군: 114.0±56.5, p=NS). 3. 이차배양 10일째에 젊은군에서 알카리성 포스파타제 활성도가 고령군에 비해 유의하게 높았다(젊은군: 935.5±115.0 U/mg, 노령군: 578.4±115.7U/mg,p.0.05). 고령군에서는 시간 경과에 따른 변화가 미약했으며 전반적으로 알카리성 포스파타제의 활성도가 젊은군에 비해 낮았다. 4. 이차배양도중 오스테오칼신 mRNA의 발현은 배양시기별로 젊은군에 비해 고령군에서 더 낮은 경향을 관찰할 수 있었다. 5. 이차배양 10일과 15일에 젊은군에서 노령군보다세포증식이 유의하게 증가된 양상을 보였다(10앓 젊은군 0.73±0.05, 노령군 0.58±0.04, p=0.05, 15일; 젊은군 0.80±0.05, 노령군 0.70±0.03, p=0.05).결론: 이상의 연구에서 저자들은 노령군에서 젊은군보다 골수 내 중간엽줄기세포의 수가 적고, 노령군에서 유래한 전구조골세포의 성숙조골세포로의 증식 및 분화가 젊은군 보다 감소해 있는 것을 관찰할 수 있었다. Background: Osteoblasts originate from osteoprogenitor cells in bone marrow stroma, termed mesenchymal stem cells (MSCs) or bone marrow stromal cells. Each MSC forms colonies (colony forming units-fibroblasts [CFL-Fs]) when cultured ex vivo. There are some reports about the age-related changes of the number and osteogenic potential of osteoprogenitor cells, but any relationship has not been clearly established in humans. In this study, we counted MSCs using CFU-Fs count and examined the proliferative capacity and differentiation potential of osteoprogenitor cells. Finally, we analyzed how these parameters varied with donor age. Methods: Bone marrow was obtained from the iliac crest of young (n=6, 27.2±8.6 years old) and old (n= 10, 57.4k6.7 years old) healthy donors. Mononuclear cells, including MSCs, were isolated and cultured in osteogenic medium. In primary culture, we compared the colony-forming efficiency of MSCs between the two groups and determined the matrix calcification. When primary culture showed near confluence, the cells were subcultured. Alkaline phosphatase activity, osteocalcin expression by RT-PCR and proliferative potential by MTT assay were examined by the time course of secondary culture. Results: At the 15th day of primary culture, the mean number of CFU-Fs was significantly higher in the younger donors (young: 148.3±28.9, old: 54.3±9.1, p=0.02) and the mean size of CFL-Fs was also larger in the younger donors than the older donors. However, matrix calcification was not different between the two groups (young: 103.6±50.6, old: 114.0±56.5, p=NS). In secondary culture, alkaline phosphatase activities were significantly lower in the older donors. The younger donors showed peak alkaline phosphatase activity at day 10, while the older donors didn't showed a remarkable peak (young: 935.5±115.OU/mg, old: 578.4±115.7U/mg, p<0.05). Total cell number as a proliferative index increased progressively during the secondary culture and a significantly greater cell number was noted in the younger donors. Osteocalcin expression was generally upregulated in the younger donors, but this was not statistically significant. Conclusion: Our study shows that the number of osteoprogenitor cells is decreased during aging and that the proliferative capacity and differentiation potential of osteoprogenitor cells seem to be reduced during aging (J Kor SOC Endocrinol 18:296-305, 2003).

      • SCISCIESCOPUS

        Direct effectiveness of pneumococcal polysaccharide vaccine against invasive pneumococcal disease and non-bacteremic pneumococcal pneumonia in elderly population in the era of pneumococcal conjugate vaccine: A case-control study

        Kim, Jong Hun,Chun, Byung Chul,Song, Joon Young,Kim, Hyo Youl,Bae, In-Gyu,Kim, Dong-Min,Choi, Young Hwa,Jun, Yoon Hee,Choi, Won Suk,Kang, Seong Hee,Kwon, Hyun Hee,Jeong, Hye Won,Kee, Sae Yoon,Hur, Jia Elsevier Ltd. 2019 Vaccine Vol. No.

        <P><B>Abstract</B></P> <P><B>Background</B></P> <P>While herd effects and serotype replacement by childhood pneumococcal protein conjugated vaccines (PCVs) continues to accumulate worldwide, direct effectiveness of 23-valent pneumococcal polysaccharide vaccine (PPV23) against pneumococcal diseases in the elderly has been challenged. We estimated the direct effectiveness of PPV23 in the elderly population.</P> <P><B>Methods</B></P> <P>For a hospital-based case-control study, cases of invasive pneumococcal disease (IPD) and non-bacteremic pneumococcal pneumonia (NBPP) (adults ≥ 65 years) were identified in 14 hospitals participated in the pneumococcal surveillance program from March 2013 to October 2015, following implementation of PPV23 national immunization program (NIP) for the elderly in the Republic of Korea. Controls matched by age, sex, and hospital were selected at ratios of 1:2 (IPD) or 1:1 (NBPP). Clinical data and vaccination records were collected. Vaccine effectiveness was calculated as (1-adjusted odds ratio) × 100.</P> <P><B>Results</B></P> <P>We enrolled 148 IPD and 557 NBPP cases, and 295 IPD and 557 NBPP controls for analyses. Overall effectiveness of PPV23 against IPD was 28.5% [95% confidence interval (CI) −5.8%–51.6%] and against NBPP was 10.2% (-15.1-30.6) in all patients ≥ 65 years. However, in subgroup analysis of patients aged 65–74 years, PPV23 was protective against IPD [effectiveness 57.4% (19.4–77.5)] and against NBPP [effectiveness 35.0% (2.3–56.7)]. Furthermore, serotype-specific effectiveness of PPV23 against IPD was 90.6% (27.6–98.8) for PPV23-unique serotypes and 81.3% (38.6–94.3) for PPV23 serotypes excluding serotype 3.</P> <P><B>Conclusions</B></P> <P>This study indicates that PPV23 with broad serotype coverage might be beneficial in preventing IPD and NBPP due to non-PCV13 serotypes in the young-elderly, with potentially increasing effectiveness in the setting of childhood PCV NIP.</P> <P><B>Highlights</B></P> <P> <UL> <LI> National immunization program for PPV23 for the elderly was implemented in Korea. </LI> <LI> PPV23 was effective against IPD and NBPP for young elderly patients aged 65–74. </LI> <LI> Effectiveness of PPV23 against IPD was higher for PPV23 unique serotypes. </LI> <LI> PPV23 was non-protective against IPD caused by PCV13 serotypes. </LI> </UL> </P>

      • 소형 연 X-선 현미경

        권영만,김한경,강성훈,김경우,윤권하 원광대학교 대학원 2008 論文集 Vol.41 No.-

        A Soft x-ray microscope operates in the 'water window' wavelength region (2.3-4.4 nm), where natural contrast between carbon (protein) and oxygen (water) allows to image a biological cell. The compact soft x-ray microscope operates at λ = 2.88 nm (430 eV) and consist of liquid-nitrogen-jet-target laser-plasma x-rays source, a tandem ellipsoidal condenser mirror for sample illumination, an objective micro zone plate, and a thinned back-illuminated charge coupled device with 1,024 × 1,024 pixels. The Liquid-nitrogen-jet-target laser-plasma source was a high brightness of 1.4×10^(12) photons/pulse·sr·line. The tandem ellipsoidal condenser mirror has 15% reflectivity. The photon flux arrived at the sample is 1.29×10^(5) photons/μ㎡ The micro zone plate was used for an objective optic, and had outermost zone width of 30 nm, zone number of 667, and diameter of 80㎛, and the focal length was 835㎛. On performance test for the compact soft x-ray microscope, the 'Siemens Star' image was obtained with a 60-nm-resolution at 380 magnification and 3 minutes exposure. I also obtained images of biological samples, such as diatom and red blood cell of a mouse with 5-10 minutes exposure.

      • KCI등재

        연 X-선 현미경을 이용한 금 나노입자 세포영상

        권영만,김한경,김경우,김선희,윤홍화,천권수,강성훈,박성훈,정선관,윤권하 韓國電子顯微鏡學會 2008 Applied microscopy Vol.38 No.3

        연 x-선 현미경은 ‘물의 창’ 영역(2.3~4.4 nm)의 파장을 이용하여, 수십 nm의 분해능으로 세포를 파괴하지 않고 살아있는 상태에서 세포의 내부구조를 관찰할 수 있어 가시광선현미경과 전자현미경을 단점을 보완하는 특징을 갖는 세포 생물학 연구에 적합한 현미경이다. 그러나 기존 연 x-선 현미경은 광원으로 방사선 가속기를 이용하기 때문에 사용이 제한적이었다. 이에, 본 연구에서는 2.88 nm의 연 x-선을 광원으로 사용하는 소형 연 x-선 현미경을 이용하여, 내포작용에 의해 금 나노입자를 포획한 HT1080과 MDA-MB 231 세포의 영상을 약 60 nm 분해능으로 획득하였다. 금 나노입자의 세포에 대한 독성을 제거하기 위하여 폴리에틸렌 글리콜을 캡핑하였고, 2.88 nm 파장의 연 x-선에 대하여 충분한 조영효과로 인하여 세포영상에서 뚜렷한 대조도를 나타내었다. 내포작용에 의해 액포에 포함되어 있는 다양한 크기의 금 나노입자 군집을 확인하였으며, 세포내부의 액포의 분포상태도 관찰할 수 있었다. 따라서 고분해능을 가진 소형 연 x-선 현미경을 이용하여 금 나노입자를 세포내의 미세기관이나 특정 단백질에 표지하면 연 x-선에 대한 조영효과의 증가에 의하여 더욱 유용한 정보를 획득할 수 있을 것으로 생각한다. A compact soft x-ray microscope operated in the ‘water window’ wavelength region (2.3~4.4 nm) was used for observing cells with nano-scale spatial resolution. To obtain cellular imaging captured with colloidal gold nanoparticles using a compact soft x-ray microscope. The colloidal gold nanoparticles showed higher contrast and lower transmission more than 7 times than that of cellular protein on the soft x-ray wavelength region. The structure and thickness of the cell membrane of the Coscinodiscus oculoides (diatome) and red blood cells were seen clearly. The gold nanoparticles within the HT1080 and MDA-MB 231 cells were seen clearly on the soft x-ray microscopy. The gold nanoparticles were aggregated within vesicles by endocytosis.

      • 多工程加工時 切削條件의 最適化

        姜昌壽,金載昊,權永斗,李永文 慶北大學校 産業開發硏究所 1979 硏究報告 Vol.7 No.-

        The selection of maching conditions based on minimum production cost and maximum production rate is analyzed for a multi-stage machining model which consists of rough cuttings, finishing cutting and honing. The problems are formulated as standard mathematical programming problems, which subject to several constraints such as cutting velocity, feed rate, required roughness etc., and mixed penalty method is used to solve the problems. The procedure used in this study can be applied to many actural multi-stage machinings.

      • 관상동맥질환 환자에서 스텐트 시술 후 재협착에 관한 연구

        강진환,권영주,박상호,한대희,이상철,김명구,변정득,최병조,심규혁,온영근,현민수,김성구 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.2

        Background and aims : In the coronary artery disease, a rate of restenosis was much decreased by placement of coronary stent than when percutaneous transluminal coronary angioplasty has been applied, but there are still important clinical problems of restenosis. There has been many progressive studies about various factors contributed to this restenosis. So, we studied a relation between restenosis after placement of coronary stent in the coronary artery disease and many clinical factors, characteristics of stenotic lesion and procedural factors, and also assessed the restenosis rate of various coronary stents. Methods : Total 58 lesions(46 cases of patients ; man 30, woman 16) were evaluated, which has been performed a follow-up coronary angiography after 6 months (mean 188 days) since coronary stent had been placed. Various stents were implanted and assessed a relation between restenosis and many factors. Results : Of 58 lesions were target stenotic studies, there were 22 of restenotic lesions(37.9%), and the restenosis rate wes statistically significant difference in the relation with diabetes mellitus(p<0.05), group of acute myocardial infarction(p<0.05) among clinical diagnosis of ischemic heart disease(stable angina, unstable angina and acute myocardial infarction) in clinical factors and with high dilation pressure of stent(p<0.05) in procedural factors. When the rate of restenosis was evaluated among implanted stents, it was lowest in the Multilink^(®) stent and highest in the Nir Royal^(®) stent(60%). Conclusion : In this study of restenosis and various factors after placement of stents in the coronary artety disease, factors such as diabetes mellitus, group of acute myocardial infarction and a dilation pressure of stent were significant related with restenosis and the restenosis rate of Multilink^(®) stent was lowest and the highest restenosis rate was of Nir Royal^(®) stent.

      • Centerless Feeder 장치의 개발

        강형모,권경우,김기길,정의식,허영환 한밭대학교 산업과학기술연구소 1994 논문집 Vol.2 No.-

        This paper presents results of the development of centerless feeding system which are applicable to bearing metal processes. As a result, the feeding system can be applied to automatic surface finishing on the bearing metal process such as bush, and has greatly effects on the increase of the prodnctiving and the decrease of the man power an effect on increase the productivity and decrease the man power and effect on increase the productivity and decrease the man power of the bush machining process.

      • KOSDAQ 시장에서의 IPO의 단기성과에 관한 연구

        강영권 東洋大學校 産業技術硏究所 2002 東洋大學校 産業技術硏究所 論文集 Vol.4 No.1

        This study examines short-term returns on IPOs(initial public offerings) of 41 samples companies registered in KOSDAQ. If any returns are found, this study analyzes the reasons. As a result, this finds that IPOs from venture companies have shown excess returns during the first 3 or 4 days after initial offering.

      • KCI등재후보

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