• Journal of Microbiology and Biotechnology
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• 제23권6호
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• pp.878-884
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• 2013

Salmonella is a major foodborne pathogen that causes a variety of human diseases. Development of ligands directly and specifically binding to the Salmonella will be crucial for the rapid detection of, and thus for efficient protection from, the virulent bacteria. In this study, we identified a RNA aptamer-based ligand that can specifically recognize Salmonella Typhimurium through SELEX technology. To this end, we isolated and characterized an RNase-resistant RNA aptamer that bound to the OmpC protein of Salmonella Typhimurium with high specificity and affinity ($K_d$ ~ 20 nM). Of note, the selected aptamer was found to specifically bind to Salmonella Typhimurium, but neither to Gram-positive bacteria (Staphylococcus aureus) nor to other Gram-negative bacteria (Escherichia coli O157:H7). This was evinced by aptamer-immobilized ELISA and aptamer-linked precipitation experiments. This Salmonella species-specific aptamer could be useful as a diagnostic ligand against pathogen-caused foodborne sickness.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
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• pp.172-172
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• 2005

• Journal of Microbiology and Biotechnology
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• 제22권9호
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• pp.1307-1309
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• 2012

Haemophilus parasuis causes contagious porcine Gl$\ddot{a}$sser's disease leading to severe losses in the swine industry. In this study, we established an efficient Escherichia coli-based system for the expression of H. parasuis major outer-membrane protein (MOMP) that has been known as a good vaccine candidate against Gl$\ddot{a}$sser's disease. Use of an E. coli-derived pelB leader sequence made it possible to produce recombinant MOMP (rMOMP) as the soluble forms without an additional refolding process. Using two different animal models, it was evaluated that the rMOMP was capable of inducing a significant immune response and providing protection against H. parasuis infection.

• 대한의생명과학회지
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• 제17권3호
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• pp.173-176
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• 2011

Free-living Acanthamoeba are eukaryotic protozoan organisms that are widely distributed in the air, water, etc such as environment. Acanthamoeba ingest the Escherichia coli which will replicate in cytoplasm of Acanthamoeba. Bacterial pathogenicity or virulence is one of important determinant factors to survive in free-living Acanthamoeba and otherwise Acanthamoebic pathogenicity is also an important factor for their interactions. Bacterial association with pathogenic strain of Acanthamoeba T1 and T4 was lower about two times than non-pathogenic T7. Bacterial invasion percentages into T1 were higher about three times than T7 but bacterial survival in T7 was increased as T1. The capsule-deletion mutant exhibited limited ability for invasion/uptake by and survival inside pathogenic Acanthamoeba T4. E. coli-outer membrane protein A (OmpA) decreased bacterial association with A. castellanii by about three times and it had higher effects than lipopolysaccharides (LPS). Under favorable conditions, the mutants were not survived in Acanthamoeba up to 24 h incubation. Therefore, this review will report pathogenic and non-pathogenic Acanthamoeba strains interactions with E. coli and its several mutants, i.e., capsule, OmpA and LPS.

• 한국축산식품학회지
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• 제33권5호
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• pp.610-616
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• 2013

본 연구에서는 영유아에게 치명적인 감염을 일으키는 C. sakazakii에 대하여 LAMP 검출법을 개발하였다. LAMP법에 의한 C. sakazakii의 검출율은 100%였으며 13개의 음성 지표군에 대해서는 모두 음성 반응을 보여 특이도가 매우 높은 것으로 판단되었다. 또한, HhaI과 NruI 두 개의 제한 효소를 LAMP product에 반응시킨 결과, 유전자의 특정 염기서열이 절단되는 것을 확인하였으며, 이를 통해 LAMP 검출법에 의해 증폭된 DNA가 C. sakazakii-specific ompA임을 확인하였다. 조제분유에 오염 된 C. sakazakii를 LAMP법으로 검출 시 검출한계는 $10^0$ CFU/mL이었으며 이는 기존의 PCR법이나 real-time PCR법에 비해 100-10,000배 높은 수준으로 민감도가 매우 높은 것으로 판단되었다. 이와 같이 높은 특이도와 민감도를 가진 LAMP 검출법은 C. sakazakii와 같은 급성 기회 감염균이나 병원성 미생물에 의한 식중독 발생시 현장에서 병원체를 간편하고 신속하게 검출할 수 있는 기술로 기대된다.

• 한국미생물·생명공학회지
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• 제32권2호
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• pp.135-141
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• 2004

인간 과립구 성장인자(hG-CSF)는 골수에서 생산되는 단백질로 호중구의 분화 및 생성을 촉진시키는 역할을 한다. 현재 재조합 hG-CSF는 암화학요법에 의한 호중구감소증, 골수이식시 호중구 감소증, 재생불량성 빈혈에 수반되는 호중구 감소증 등으로 적응증이 확대되고 있다. 본 연구에서는 OmpA signal sequence를 삽입하여 인간 과립구 성장인자(hG-CSF)가 분비발현되도록 고안된 T7 promoter 에 의하여 발현되는 pYRCl 발현백터를 제조하였다. E. coli BL2l (pYRCl) 발현시 $37^{\circ}C$에서 배양하는 경우 많은 양의 봉입체(aggregates)를 형성한다. 이에 비하여 $10\mu$M ucose를 포함하는 변형된 MBL배지에서 10 g/$\ell$IPTG를 유도물질로 7시간동안 $25^{\circ}C$에서 배양하였을 때 전체 periplasm단백질의 15%가 soluble rhG-CSF이었다. 또한, 유가식 배양방법을 사용하여 E. coli BL2l(pYRCl)에서 soluble rhG-CSF의 생산조건을 조사하였다. 유가식 배양에서 rhG-CSF의 발현량이 비증식속도를 $0.43 h^{-1}$ 에서 0.14 $h^{-1}$ 으로, 유도 배양시간을 최적화함으로써 rhG-CSF의 발현량이 4.4mg/$\ell$에서 24mg/$\ell$ 로 증가하였다.

• 대한임상검사과학회지
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• 제54권2호
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• pp.119-124
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• 2022

녹농균(Pseudomonas aeruginosa), 대장균(Escherichia coli) 및 포도알균(Staphylococcus aureus)은 기회감염균이다. 또한 이들 세균은 다제내성(Multiple-Drug Resistance, MDR) 세균의 성질을 가지는 것으로 알려져 있다. 녹농균, 대장균, 포도알균에 대한 다양한 효능을 지닌 6가지 발효액의 항균활성을 분석하였다. 발효액을 섭취했을 때 대장균에서 유전적 발현 변화가 일어나는지 알아보기 위해 annealing control primer를 사용하여 유전자발현 분석을 수행하였다. 디스크확산법을 통해 무화과식초와 대봉감식초가 다른 발효액에 비해 억제대의 크기가 가장 크게 나타났고, 토종약초발효소는 항균효과가 없었다. 대장균에 5% 무화과식초를 처리하여 21일간 매일 계대배양하여 Escherichia coli O157:H7 OmpW gene for outer membrane protein W 유전자 발현이 감소하며, Synthetic construct Lao1 gene for L-amino acid oxidase, complete cds 유전자가 발현이 증가함을 확인하였다. 발효액 중에서 특히 무화과식초를 섭취하는 것은 우리 주변에 항상 존재하는 대장균에 대해 방어능력을 더욱 단단하게 가질 수 있음을 의미하며, 나아가 다제내성균에 대한 천연치료제로 유용하게 쓰일 수 있기를 기대한다.

• Journal of Life Science
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• 제9권1호
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• pp.35-39
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• 1999

Elecrophoreticl analysis of a 36 kDa protein was runned by SDS-PAGE, isoelectric focusing (IEF) and two dimensional electrophoresis pattern. Major 36 kDa and 25, 46, 48, 66 kDa protein were detected by Coomassie blue stain on SDS-PAGE. Major 36kDa protein was eluted for production of antiserum for serological analysis, IEF and two dimensional electrophoresis. Isoelectric point of 36kDa was aout pH 8.5. Two dimensional electrophoresis of eluted 36kDa showed one point on the gel. Anti-36 kDa serum made by newzilland rabbit for serological test. In ELISA, final titer of antibody was 100×{TEX}$2^5}${/TEX} : 1. Neutralize ability of serum was examined by slide agglutination test and colonization test in rat. Anti-36 kDa serum agglutinated whole cell of V. vulnificus were inhibited colonization on intestine in rat. Accordingly In this paper contain some electrophoretical analysis and serological test of a 36 kDa OMP of V. vulnificus.

• 천문학회지
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• 제50권5호
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• pp.139-149
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• 2017

The Korea Astronomy and Space Science Institute plans to develop a coronagraph in collaboration with National Aeronautics and Space Administration (NASA) and to install it on the International Space Station (ISS). The coronagraph is an externally occulted one-stage coronagraph with a field of view from 3 to 15 solar radii. The observation wavelength is approximately 400 nm, where strong Fraunhofer absorption lines from the photosphere experience thermal broadening and Doppler shift through scattering by coronal electrons. Photometric filter observations around this band enable the estimation of 2D electron temperature and electron velocity distribution in the corona. Together with a high time cadence (<12 min) of corona images used to determine the geometric and kinematic parameters of coronal mass ejections, the coronagraph will yield the spatial distribution of electron density by measuring the polarized brightness. For the purpose of technical demonstration, we intend to observe the total solar eclipse in August 2017 with the filter system and to perform a stratospheric balloon experiment in 2019 with the engineering model of the coronagraph. The coronagraph is planned to be installed on the ISS in 2021 for addressing a number of questions (e.g., coronal heating and solar wind acceleration) that are both fundamental and practically important in the physics of the solar corona and of the heliosphere.

• 한국임상약학회지
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• 제10권3호
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• pp.111-119
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• 2000

The objective of this study was to evaluate the efficacy and the pattern of regimens prescribed for the treatment of peptic ulcer disease in a regional community hospital. 226 patients were treated as an outpatient and followed for one year. 88 patients $(38.9\%)$ had gastric ulcer (GU) alone, 6 patients $(2.7\%)$ had duodenal ulcer (DV) alone, 5 patients $(2.2\%)$ had gastroesophageal reflux disease (GERD) alone, 25 patients $(11.1\%)$ had both GU and DU, 88 patients $(38.9\%)$ had both GU and GERD, and 14 patients $(6.2\%)$ had both DU and GERD. During this study period no one was treated for Zollinger-Ellison Syndrome. The disease showed higher occurrence in male population (139 patients, $61.5\%$) and among the ages of 30 and 40 $(62.4\%)$. The average age of these patients was 41.3 years and there was no difference between the genders. $81.4\%$ of these patients underwent CLO test to check for the existence of Helicobacter and $66.3\%$ of these Patients showed the positive response. $65.6\%$ of patients with GU and $80\%$ of patients with DU showed the positive response and there was no difference between the genders $(65.4\%\;vs.\;67.6\%)$. 184 patients $(81.4\%)$ were deemed to be cured based on the disappearance of their symptoms after completing the regimens. Compliance rate did not differ for gender or different diseases, while showing a difference in age. Patients between the ages of 20 to 30 years old showed the worst compliance rate. In addition, the compliance was lower among the patients who had previous occurrence of the disease, and this was more evident among female patients. Although 184 patients out of the total 226 patients were deemed to be cured, 36 patients $(20.65\%)$ of these returned to the hospital for relapsed diseases within one year. The factors that affected for patients to relapse were the diseases accompanied by ulcer and social environments, such as smoking, alcohol consumption, and previous history of the diseases (smoking P<0.001, alcohol consumption P<0.02, previous history of disease P<0.05). The regimen using $H_2$ receptor antagonists+tripotassium dicitrato bismuthate+clarithromycin showed the lower rate of relapse, and the regimens of omeprazole (OMP)+amoxicillin+tripotassium dicitrato bismuthate and OMP+amoxicillin+metronidazole showed better compliance rate. Patient education by pharmacists on the importance of compliance to regimens and the risk factors fer relapse can provide a better patient care. This would ultimately result in more cost-effective treatments by preventing additional cost for treating relapsed symptoms in approximately $20\%$ of patients.