• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2013년도 춘계학술대회
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• pp.1012-1014
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• 2013

DNA-DNA hybridization method with four oligonucleotide-specific probes was used simultaneously for differentiation and identification of four Mycobacterium species (Mycobacterium tuberculosis, M. avium, M. intracellulare, and M. kansasii). This DNA-DNA hybridization method with 4 oligonucleotide-specific probes, which targets in the rpoB region of 4 Mycobacteria species, respectively, was tested on 322 clinical isolates. Using DNA-DNA hybridization method, we detected M. tuberculosis (282 strains), M. avim (7 strains), M. intracellulare (9 strains), and M. kansasii (3 strain) from 322 clinical isolates. This result was compared with conventional biochemical test and rpoB DNA sequence analysis of this clinical isolates. We confirmed identification of Mycobacterium tuberculosis, M. avium, M. intracellulare, and M. kansasii with high sensitivity (100 %) and specificity (100 %). This DNA-DNA hybridization method could be performed within 4 hours at least. Therefore, we suggest that DNA- DNA hybridization method using 4 rpoB DNA probes of Mycobacteria could be used for accurate, rapid, convenient detection and identification of Mycobacterium tuberculosis, M. avium, M. intracellulare, and M. kansasii in clinical samples.

• 전자공학회논문지SC
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• 제48권2호
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• pp.86-90
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• 2011

전계효과 트랜지스터(FETs)를 이용한 전하 검출형 DNA센서는 DNA가 가지고 있는 음전하를 중성화 시키는 양이온의 영향은 매우 중요하다. 본 논문에서는 양이온 농도에 의존하는 Debye length에 관한 연구를 통해 DNA 검출감도를 평가하였다. Debye length는 낮은 농도의 NaCl 용액에서 긴 거리를 유지하며, Debye length가 높은 용액에서 DNA가 가지고 있은 음전하는 게이트 채널에 보다 많은 영향을 미친다. 용액내 NaCl농도가 1 mM인 버퍼 용액에서 상보적 DNA의 hybridization에 의한 전계효과 트랜지스터의 게이전압은 21 mV 시프트 했으며, NaCl 농도가 10 mM인 버퍼 용액에서는 7.2 mV, NaCl농도가 100 mM인 버퍼 용액에서는 전계효과 트랜지스터의 게이트 전압이 5.1 mV 각각 시프트 하였다. 이러한 결과를 바탕으로 전계효과 트랜지스터를 이용한 전하 검출형 DNA센서의 검출 감도는 Debye length에 의존하는 것을 규명하였다.

• 한국동물학회지
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• 제31권3호
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• pp.218-224
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• 1988

Drosophila melanogaster의 세계 14지역 계통으로부터 mitochondrial DNA(mtDNA)를 추출하여, 제한 요소에 의하여 mtDNA종내 변이를 조사하였다. 그 결과, site variation(Hpall와 Haelll 및 Seal효소)과 length variation(최대550bp)이 나타났다. 또한 6종류(Ml, M2, M3, M4, M6 및 M7)의 mtDNA genotype이 검출되었으며, 종내 평균 염기 치환율은 1.88%로써 낮은 지역 분화(low divergence)를 나타내었다. 그러나 일본의 Ogasawara계통의 M5 type은 본 연구에서는 검출되지않았다. 이처럼 지역 계통간의 낮은 지역 분화는 세계14지역 계통의 D. melanogaster가 최근에 소수의 개체로부터 확산되었기 때문에 집단전체에 아직 충분한 mtDNA변이가 축적되지 않았거나 혹은 지리적 격리가 충분함에도 불구하고 지역 계통간에 빈번한 migration이 일어났기 때문에 mtDNA의 지역 분화가 방해되지않은 것으로 추측된다.

• Journal of Plant Biology
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• 제37권1호
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• pp.101-109
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• 1994

Chlamydomonas reinhardtii 배우체 유도기 동안에 polyamine 생합성 억제제인 MGBG[methylglyoxal bis-(guanylhydrazone); SAMDC 억제제] 1mM 처리구와 정상 대조구에서의 polyamine 함량 변화와 Chlamydomonas의 ct-DNA methylation과의 상호 연관성을 조사한 결과, 전반적으로 137C(＋)와 137C(-)의 정상 대조구에서 polyamine 수준은 배우체 유도기 전반에 걸쳐서 감소추세로 나타났으나, 특히 137C(＋)가 137C(-)보다 polyamine 함량이 많았으며 동시에 감소량도 컸다. 1mM MGBG 처리구에서는 137C(＋)의 spermidine 함량이 정상 대조구보다 증가하였다. In vitro에서 ctDNA methylation에 대한 MGBG의 영향은 정상 대조구에서보다도 1mM MGBG 처리구에서 약 20-30%의 ctDNA methylation 감소를 나타내었다. 또한, MGBG는 in vitro에서 DNA methylase에 대하여 억제효과를 나타내어TEk.

• 생명과학회지
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• 제17권2호통권82호
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• pp.279-285
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• 2007

위암 환자 30명과 결장암 환자 30명의 암 조직과 그 주위의 정상 조직을 구분하고, 암 조직과 정상조직의 쌍을 찾지 못한 경우의 위암 조직 8개와 결장암 조직 10개의 각 조직에서 Mycoplasma DNA의 존재 유무를 PCR법으로 확인하고 PCR산물에서 DNA의 염기서열을 분석하여 Mycoplasma DNA 서열과 비교함으로써 Mycoplasmas를 검색한 결과 다음과 같은 결론을 얻었다. 위암 조직과 그 주위 조직 30개 중에서 Mycoplasma DNA가 검출된 것은 각각 13개(43.3%)와 18개(60%)이었으며, 결장암 조직과 그 주위 조직 30개 중에서 Mycoplasma DNA가 검출된 것은 각각 12개(40%)와 15개(50%)이었다. Mycoplasma DNA가 검출된 위암 조직에서 mycoplasma 균종의 분리빈도는 M. faucium, M. subdolum, M. salivarium, M. auris, M. hyosynoviae, M. conjunctivae의 순이었다. Mycoplasma DNA가 검출된 위암 조직 주변의 정상조직에서 mycoplasma 균종은 M. facium, M. subdolum, M. salivarium, M. auris, M. hyosynoviae, M. bovigenitalium와 M. pulmonis의 순이었다. Mycoplasma DNA가 검출된 결장암 조직에서 mycoplasma 균종의 분리 빈도는 M. faucium, M. subdolum, M. salivarium, M. auris, M. hyosynoviae), M. synoviae M. bovigenitalium, M. gallinarum, M. moatsii의 순이었다. Mycoplasma DNA가 검출된 결장암 조직 주변의 정상조직에서 mycoplasma 균종은 M. faucium, M. subdolum, M. salivarium, M. auris, M. hyosynoviae, M. bovis, M. opalescens, M. bovigenitalium, M. gallinarum와 M. moatsii의 순이었다. 이상의 결과에서 위암 및 결장암 조직 보다 암 주위의 정상 조직에서 Mycoplasma DNA의 검출율이 높았으며, 검출된 Mycoplasma 균종도 암 조직과 정상 조직에서 차이가 없었으므로 이들 암과 Mycoplasma와는 상관관계가 없는 것으로 생각된다.

• BMB Reports
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• 제52권11호
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• pp.635-640
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• 2019

CpG-DNA triggers the proliferation and differentiation of B cells which results in the increased production of antibodies. The presence of bacteria-reactive IgM in normal serum was reported; however, the relevance of CpG-DNA with the production of bacteria-reactive IgM has not been investigated. Here, we proved the function of CpG-DNA for the production of bacteria-reactive IgM. CpG-DNA administration led to increased production of bacteria-reactive IgM both in the peritoneal fluid and serum through TLR9 signaling pathway. When we stimulated B cells with CpG-DNA, production of bacteria-reactive IgM was reproduced in vitro. We established a bacteria-reactive monoclonal IgM antibody using CpG-DNA stimulated-peritoneal B cells. The monoclonal IgM antibody enhanced the phagocytic activity of RAW 264.7 cells against S. aureus MW2 infection. Therefore, we suggest that CpG-DNA enhances the antibacterial activity of the immune system by triggering the production of bacteria-reactive IgM. We also suggest the possible application of the antibodies for the treatment of antibiotics-resistant bacterial infections.

• Journal of Plant Biology
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• 제32권4호
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• pp.331-341
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• 1989

DNA methyltransferase was purified 282.6-fold from Chlamydomonas reinhardtii 21gr (mt+) gametic cell to examine the effect of polyamine on the enzyme acctivity. Polyacrylamide gel electrophoresis(PAGE) revealed at least three bands(1 major band, 2 minor bands). Among these, the major band represents DNA methyltransferase. Polyacrylamide gel electrophoresis in the presence of 0.1% sodium dodecylsulfate(SDS-PAGE) revealed a major band with M.W. 60,000. DNA methyltransferase activity was inhibited more effectively by spermine than by spermidine, and the inhibition by putrescine was smaller than spermine and spermidine. DNA methyltransferase activity was inhibited by 40% and 53% at 5mM and 20mM spermine, respectively. In the case of spermidine, the inhibition was 35% at 10mM and 44% at 20mM. However, the inhibition by putrescine appeared only above 5mM and reached about 25% at 20mM.

• Journal of Radiation Protection and Research
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• 제42권1호
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• pp.63-68
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• 2017

Background: The combined effect of the low energy electron (LEE) irradiation and $Cu^{2+}$ ion on DNA damage was investigated. Materials and Methods: Lyophilized pBR322 plasmid DNA films with various concentrations (1-15 mM) of $Cu^{2+}$ ion were independently irradiated by monochromatic LEEs with 5 eV. The types of DNA damage, single strand break (SSB) and double strand break (DSB), were separated and quantified by gel electrophoresis. Results and Discussion: Without electron irradiation, DNA damage was slightly increased with increasing Cu ion concentration via Fenton reaction. LEE-induced DNA damage, with no Cu ion, was only 6.6% via dissociative electron attachment (DEA) process. However, DNA damage was significantly increased through the combined effect of LEE-irradiation and Cu ion, except around 9 mM Cu ion. The possible pathways of DNA damage for each of these different cases were suggested. Conclusion: The combined effect of LEE-irradiation and Cu ion is likely to cause increasing dissociation after elevated transient negative ion state, resulting in the enhanced DNA damage. For the decrease of DNA damage at around 9-mM Cu ion, it is assumed to be related to the structural stabilization due to DNA inter- and intra-crosslinks via Cu ion.

• Parasites, Hosts and Diseases
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• 제42권3호
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• pp.129-135
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• 2004

We compared the DNA sequences of the genus Metagonimus: M. yokogawai, M. takahashii, and M. miyatai. We obtained 288 D1 ribosomal DNA (rDNA) and mitochondrial cytochrome c oxidase subunit I (mtCOI) fragments from the adult worms by PCR, that were cloned and sequenced. Phylogenetic relationships inferred from the nucleotide sequences of the 28S D1 rDNA and mtCOI gene. M. takahashii and M. yokogawai are placed in the same clade supported by DNA sequence and phylogenie tree analysis in 28S D1 rDNA and mtCOI gene region. The above findings tell us that M. takahashii is closer to M. yokogawai than to M. miyatai genetically. This phylogenetic data also support the nomination of M. miyatai as a separate species.

• 한국환경성돌연변이발암원학회지
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• 제19권1호
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• pp.34-38
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• 1999

Fumonisin B1 is a secondary metabolite of Fusarium moniliforme, a contaminant of corn and corn product. Fumonisin B1 has been shown to be responsible for major toxicological effects of the fungus in rats, horses, and pigs. Fumonisin B1 induced λ DNA fragmentation, which was increased with incubation time, reducing agent NADPH and metal ion (Cu2+). The DNA damage was inhibited by dimethyl sulfoxide (DMSO) or mannitol as radical scavenger for free radicals. DNA fragmentation, induced by fumonisin B1 in the presence of 1 mM NADPH and 0.1 mM CuCl2, was inhibited by 100 mM DMSO. By the in vitro reaction of fumonisin B1 with supercoiled plasmid pBR322 DNA, plasmid DNA was relaxed, eventually linearized in the agarose gel electrphoresis. From rifampicin sensitive E. coli CSH138 in bacterial mutagenesis system, the rifampicin resistant E. coli mutants were obtained by fumonisin B1. These results suggest that fumonisin B1 may be a possible environmental mutagen in bacterial mutagen assay system.