• 대한화학회지
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• 제52권3호
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• pp.273-280
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• 2008

결핵은 전 세계적으로 심각한 공중보건문제로 남아있다. 최근에는 결핵의 발병률이 증가하고 있는 추세이며 이에 따른 결핵의 정확한 조기치료와 심각한 부작용, 그리고 전염을 방지하기 위해서는 신속하고 정확한 결핵의 진단이 절실하게 필요하다. 본 연구에서는 결핵유전자를 빠르게 검출하는데 있어서 등온증폭법이 가지고 있는 높은 특이성과 신속성에 대하여 평가하였다. 결핵 DNA의 순차적 10배위 정량희석 DNA를 사용하였으며 일반PCR 방법과 등온증폭법의 실험방법의 검출한계, 민감성, 특이성, 재현성을 비교하였다. 그 결과 등온 증폭법은 빠른 증폭 시간과 높은 민감성, 높은 특이성을 가지고 있었으며 병원이나 연구실, 진단 검사실 등에서 결핵유전자를 빠르고 정확하게 진단할 수 있는 유용한 방법이 될 수 있을 것이다.

• 대한의생명과학회지
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• 제20권4호
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• pp.250-255
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• 2014

Mycobacterium tuberculosis (MTB) resides and replicates inside macrophages. In our previous report, we reported that CD8+ T cell-mediated immune responses specific for the peptide derived from MTB RNA polymerase beta-subunit ($RpoB_{127-135}$) could be induced in TB patients expressing HLA-$A^*0201$ subtype. In order to examine whether $RpoB_{127-135}$ specific CD8+ T cells can recognize MTB infected macrophages in vitro, CD8+ T cell lines specific for $RpoB_{127-135}$ peptide were generated from peripheral blood mononuclear cells (PBMCs) of healthy HLA-$A^*0201$ subjects by in vitro immunization technique. In this study, we observed $RpoB_{127-135}$ specific CD8+ T cells could recognize and destroy macrophages infected with MTB for 2 to 4 days. $RpoB_{127-135}$ specific CD8+ T cell immune response was inducible from PBMC of healthy subjects expressing HLA-$A^*0206$ subtype, one of HLA-A2 supertype members. Next, we investigated the HLA-I processing mechanism of $RpoB_{127-135}$ peptide in MTB infected macrophages. As a result, the presentation of the MTB derived epitope peptide, $RpoB_{127-135}$, to CD8+ T cells was not inhibited by the treatment with brefeldin-A (ER-Golgi transport inhibitor) or lactacystin (proteasome inhibitor), which blocks the classical HLA-I processing pathway. However, $RpoB_{127-135}$ specific CD8+ T cell activity was blocked either by the blocking agent for the endocytosis (cytochalasin D) or by the blocking antibody (W6/32) for HLA-I molecules. Therefore, the $RpoB_{127-135}$ peptide may be processed by accessing the alternate HLA-I processing pathway. Understanding the processing and presentation mechanisms of the MTB derived proteins will help to improve the efficacy of vaccines and the efficiency of therapeutic agents for TB.

• 환경위생공학
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• 제16권2호
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• pp.91-99
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• 2001

Cross linked chitosan beads showed high selective adsorption abilities in order of $Au^{3+}$ > $Hg^{2+}$ > $Cu^{2+}$ > $Cd^{2+}$ > $Pt^{4+}$ > ${UO_2}^{2+}$ ions in mixed solution of various metal ions at pH 4.5. N-methyltyiobenzylated chitosan beads(MTB-chitosan beads) were prepared treating with p-(methylthio) benzaldehyde after cross linking of chitosan beads to give them a high selectivity in adsorption of metal ions. The MTB-chitosan beads demonstrated their selectivity on precious metals among various metal ions distinctively. Particularly, the MTB-chitosan had a peculiar selective adsorption on $Pd^{2+}$, $Au^{2+}$, and $Hg^{2+}$ions whilst the cross linked chitosan beads showed its high adsorption on $Pd^{2+}$ at pH 1.1. On the other hand, the cross linked chitosan beads showed its superiority in selective adsorption on $Au^{2+}$, $Cu^{2+}$, and $Hg^{2+}$ions to the MTB-chitosan at pH 4.5 of the test solution. Thus metal selectivities were given to chitosan beads through chemical modifications.

• 대한의생명과학회지
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• 제15권4호
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• pp.295-300
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• 2009

Tuberculosis caused by Mycobacterium tuberculosis (MTB) still remains to be the most dreadful infectious disease affecting almost every country. In the present study, we developed a simple and rapid but accurate and sensitive assay method for detecting MTB using microplate hybridization assay. For this, a selective region of the rpoB gene was used to design PCR primers, and MTB and Mycobacterium genus-specific probe molecules. The specificity of the assay was confirmed using fifteen different mycobacterial reference strains and twelve different non-mycobacterial reference strains, and the sensitivity was determined to be 100 fg using genomic DNA of MTB reference strain, H37Rv. Subsequently, a total of 62 sputum samples with diverse smear scores and culture positive results were used to evaluate the kit performance. In brief, the specificity and the sensitivity of the assay were 100% and 98.4%, respectively.

• 대한의생명과학회지
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• 제18권3호
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• pp.201-209
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• 2012

Apoptosis is a physiological programmed cell death process. Tubercle bacilli inhibit apoptosis of alveolar macrophages and phagolysosome fusion. We investigated whether the Bcl-2 family anti-apoptotic member, Bfl-1/A1, plays an important role in the anti-apoptotic process during mycobacterial infection. PMA-treated human monocytoid THP-1 cells were infected with mycobacteria (H37Rv, BCG, and K-strain) at a multiplicity of infection (MOI) of 10 for 0, 1.5, 3, 6, 9, 12, 18, 24, 48, or 72 h. In addition, PMA-treated THP-1 cells were pretreated with specific inhibitors for 45 min before stimulation with mycobacteria at an MOI of 10 for 4 h. After the indicated time, the cells were subject to reverse transcription-polymerase chain reaction (RT-PCR) analysis, and a Bfl-1/A1-specific Western blot was performed. In PMA-differentiated THP-1 cells, the expression level of Bfl-1/A1 mRNA was increased by Mycobacterium tuberculosis (MTB) H37Rv infection. The mRNA level of Bfl-1/A1 peaked 3 h after MTB infection, then declined gradually until 9 h. However, Bfl-1/A1 mRNA induction gradually re-increased from 24 h to 72 h after MTB infection. No difference in Bfl-1/A1 expression was detected following infection with MTB H37Rv, K-strain, or M. bovis BCG. These results were not dependent on mycobacterial virulence. Moreover, mRNA levels of other anti-apoptotic molecules (Mcl-1, Bcl-2, and Bcl-xL) were not increased after MTB H37Rv or K-strain infection. These results suggest that mycobacteria induce the innate immune host defense mechanisms that utilize Bfl-1/A1 molecules at early time points, regardless of virulence.

• 대한의생명과학회지
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• 제20권3호
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• pp.162-167
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• 2014

Tuberculosis (TB) is one of the major global health problems and it has been estimated that in 5~10% of Mycobacterium tuberculosis (MTB)-infected individuals, the infection progresses to an active disease. Numerous cytokines and chemokines regulate immunological responses at cellular level including stimulation and recruitment of wide range of cells in immunity and inflammation. In the present study, the mRNA expression levels of eight host immune markers containing of IFN-${\gamma}$, TNF-${\alpha}$, IL-2R, IL-4, IL-10, CXCL9, CXCL10, and CXCL11 in whole blood cells from active pulmonary TB patients were measured after T-cell mitogen (PHA) and MTB specific antigens (ESAT-6, CFP-10, and TB7.7). Among the TH1-type factors, IFN-${\gamma}$ mRNA expression was peaked at 4 h, TNF-${\alpha}$ and IL-2R mRNA expression was significantly high at the late time points (24 h) in active TB patients, TH2-type cytokine (IL4 and IL10) mRNA expression levels in both active TB and healthy controls samples did not changed significantly, and the mRNA expression of the three IFN-${\gamma}$-induced chemokines (CXCL9, CXCL10, and CXCL11) were peaked at the late time points (24 h) in active TB patients after MTB specific antigen stimulation. In conclusion, the mRNA expression patterns of the TB-related immune markers in response to the T-cell mitogen (PHA) differed from those in response to MTB specific antigens and these findings may helpful for understanding the relationship between MTB infection and host immune markers in a transcripts level.

• 대한의생명과학회지
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• 제13권4호
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• pp.325-332
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• 2007

Cell-mediated immune response (CMI) is a major immune protective mechanism against tuberculosis (TB) infection. Among several components involved in CMI, recent studies suggest that CD8+ T cells are important in controlling TB infection. In our previous report, we defined four Mycobacterium tuberculosis (MTB) derived epiotpe peptides specific for HLA-A*0201-restricted CD8+ T cells. These four peptides are $PstAl_{75-83}$, $ThyA_{30-38}$, $RpoB_{127-135}$ and $85B_{15-23}$. In this study, these epitope peptides specific CD8+ T cell responses in tuberculous pleurisy were investigated using ex vivo $IFN-\gamma$ elispot assay and intracellular $IFN-\gamma$ staining method. As a result, we observed these epitope peptide specific CD8+ T cell responses are induced in all three patients with tuberculous pleurisy suggesting that CD8+ T cells are involved in protective immune mechanism against MTB infection in tuberculous pleurisy. However, the CMI to mitogens and MTB antigens from pleural fluids of patients with tuberculous pleurisy does not seem to correlate with that from peripheral blood, although the sample size is too small to make any conclusion. In sum, the MHC I restricted CD8+ T cell responses seem to be induced efficiently in the pleural fluids, at the site of TB infection, in which the CMI is actively induced. In addition, these experiments suggest that MHC I restricted CD8+ T cell mediated immune responses are also involved in protective mechanism against MTB infection in extra-pulmonary TB.

• Journal of Microbiology and Biotechnology
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• 제29권3호
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• pp.489-499
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• 2019

Subunit vaccines are safer and more stable than live vaccines although they have the disadvantage of eliciting poor immune response. To develop a subunit vaccine, an effective delivery system targeting the key elements of the protective immune response is a prerequisite. In this study, oxidized carbon nanospheres (OCNs) were used as a subunit vaccine delivery system and tuberculosis (TB) was chosen as a model disease. TB is among the deadliest infectious diseases worldwide and an effective vaccine is urgently needed. The ability of OCNs to deliver recombinant Mycobacterium tuberculosis (Mtb) proteins, Ag85B and HspX, into bone marrow derived macrophages (BMDMs) and dendritic cells (BMDCs) was investigated. For immunization, OCNs were mixed with the two TB antigens as well as the adjuvant monophosphoryl lipid A (MPL). The protective efficacy was analyzed in vaccinated mice by aerosol Mtb challenge with a virulent strain of Mtb and the bacterial burdens were measured. The results showed that OCNs are highly effective in delivering Mtb proteins into the cytosol of BMDMs and BMDCs. Upon immunization, this vaccine formula induced robust Th1 immune response characterized by cytokine profiles from restimulated splenocytes and specific antibody titer. More importantly, enhanced cytotoxic $CD8^+$ T cell activation was observed. However, it did not reduce the bacteria burden in the lung and spleen from the aerosol Mtb challenge. Taken together, OCNs are highly effective in delivering subunit protein vaccine and induce robust Th1 and $CD8^+$ T cell response. This vaccine delivery system is suitable for application in settings where cell-mediated immune response is needed.

• 한국산학기술학회논문지
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• 제12권7호
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• pp.3062-3071
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• 2011

기업의 소유구조와 기업 가치에 미치는 영향에 관하여, 일반 제조업과는 상이한 업종상 회계상 특성을 가진 건설기업의 경영성과를 소유구조에 따라 일반 제조기업과 비교한 연구는 미진하였다. 본 연구에서는 1998년도부터 2007년도까지 우리나라 KOSPI 상장기업의 주요 주주지분율(내부지분율, 외국인지분율, 기관투자자지분율)의 증감에 따른 경영성과와의 상호 연관성 여부와 지분구조에 따라 제조기업과 건설기업과의 성과 차이에 대하여 비교하고자 한다. 실증결과를 요약하면, 첫째 외국인지분의 증가는 MTB에 정(+)의 영향을 미치어 외국인투자자지분이 기업의 장기적 경영성과(MTB)에 긍정적 영향을 준다는 선행 연구의 결과를 지지 하였으며, 내부지분율의 증가는 MTB에 부(-)의 영향을 미치는 것으로 나타나 선행연구의 경영자안주가설을 지지 하였다. 단지, 기관투자자지분율과 MTB와의 관련성은 적극적 감시가설을 언급한 앞선 여러 연구의 결과에도 불구하고 연동성을 찾아 볼 수 없었다. 또한 소유구조와 ROA의 연동성을 살펴보면 내부지분율 및 외국인지분율의 증가는 ROA에 정(+)의 영향을 미치나 기관투자자 지분율의 증가는 부(-)의 영향을 미치어 앞선 기관투자자의 적극적 감시가설과는 다른 결과를 보여주었다. 두 번째 지분구조에 따라 건설업과 제조업간의 경영성과가 차이가 있는지를 검증한 결과 내부지분율과 건설업유무, 외국인지분율과 건설업유무, 기관투자가지분율과 건설업유무 모두 MTB 와 ROA에 통계적으로 차이를 주지는 못하는 것으로 나타나 발주, 생산 및 회계상 수익의 인식 등 제조업과의 다른 특성에도 불구하고 지분구조에 따른 건설기업과 제조기업의 경영성과에는 차이는 없음을 알 수 있었다.

• Journal of Microbiology
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• 제42권3호
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• pp.239-242
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• 2004

This study examined the detection rate of the hepatitis B virus (HBV) and Mycobacterium tuberculosis (Mtb) in serum and saliva samples, respectively, from 120 dental patients who were unaware if they have or had either hepatitis or tuberculosis. The frequencies of HBsAg and anti-HBs were determined using an immunochromatic assay. Mtb positivity was determined by the PCR method. Of the 120 patients, 7 (5.8％) were HBV positive and 30 (25.0％) were Mtb positive. This highlights the fact that dental health care workers (DHCWs) can be exposed to the risk of infection from blood- or saliva-borne pathogens as a consequence of their work. Therefore, it is very important to prevent cross infection between patients and dental personnel. Accordingly, laboratory tests prior to surgical treatment are needed to determine the infectious state of dental patients in order to prevent the transmission of infectious diseases in dental clinics.