• Journal of information and communication convergence engineering
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• 제17권1호
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• pp.49-59
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• 2019

Biosensors, which are analysis devices used to convert biological reactions into electric signals, are made up of a receptor component and a signal transduction part. Graphene quantum dots (GQDs) and carbon quantum dots (CQDs) are new types of carbon nanoparticles that have drawn a significant amount of attention in nanoparticle research. The unique features exhibited by GQDs and CQDs are their excellent fluorescence, biocompatibility, and low cytotoxicity. As a result of these features, carbon nanomaterials have been extensively studied in bioengineering, including biosensing and bioimaging. It is extremely important to find biomaterials that participate in biological processes. Biomaterials have been studied in the development of fluorescence-based detection methods. This review provides an overview of recent advances and new trends in the area of biosensors based on GQDs and CQDs as biosensor platforms for the detection of biomaterials using fluorescence. The sensing methods are classified based on the types of biomaterials, including nucleic acids, vitamins, amino acids, and glucose.

• 식품과학과 산업
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• 제52권1호
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• pp.68-83
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• 2019

The history of fermented condiments symbolizes that of the fermentation industry of Korea. Daesang Co. (ex Miwon) initiated the production of MSG using fermentation process in 1960 for the very first time. Ever since, both Daesang and CJ Co. (ex Cheil Jedang) have scrambled for taking up bigger share of Korean market in the field of MSG, IG-coated MSG, and mixed seasoning. It is noteworthy that both companies have powerfully contributed to the development of Korean fermentation industry. Daesang initiated exporting plants to Indonesia in 1973, whereas CJ has become the global leader of the IMP market. Furthermore, both of them have developed such as not only amino acids but also nucleic acid-related substances, organic acids, enzymes etc. with glutamic acid as a platform. It is anticipated that the two will develop the newly diversified edible substances and various kinds of fermented foods along with new food cultures.

• 대한화학회지
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• 제36권3호
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• pp.460-465
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• 1992

Xanthomonas citri의 5S rRNA를 분리, 정제하여 효소적 방법과 화학적 방법으로 그 구조를 결정하였다. 이 5S rRNA는 119개의 누클레오티드로 구성되어 있으며 변형된 누클레오시드를 함유하지 않는다. 그리고 이 5S rRNA는 X. maltophilia의 것처럼 5'-말단에 가외의 우리딘 잔기를 하나 더 가지고 있다. 결정한 X. citri의 5S rRNA의 이차구조는 다른 원핵세포의 것들에 대해서 제안된 일반 모형들과 매우 유사하며 [De Wachter et al., Biochimie, 64, 311 (1982); Specht et al., Nucleic Acids Res., 18, 2215 (1990); Cho et al., Proceedings of the First Symposium on Biomolecules, p. 9 (1991)], 5개의 이중나선 줄기와 5개의 단일가닥 고리 그리고 2개의 내밀린 구조를 가진다.

• 대한수의학회지
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• 제51권2호
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• pp.129-137
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• 2011

Swine diseases could be caused by unrecognized or minor pathogens. In this study, two unknown cytopathogenic agents were isolated from swine, through cell culture. In order to identify these two cytopathogenic agent (designated CP129 and #2045-7), a particle associated nucleic acids PCR (PANPCR) from previous paper was used with simple modification. The cloning procedure was more specified in this study by adding cell control system. According to the modified PAN-PCR, two and four agentsspecific DNA sequences were obtained from CP129 and #2045-7, respectively, and they were identified as Mycoplasma (M.) hyorhinis and Mammalian orthoreovirus by nucleotide BLAST. Since M. hyorhinis (CP129) was filterable and non-visible by microscope, this unusual virus-like nature of M. hyorhinis (CP129) was discussed. Especially, the reovirus (#2045-7) was a serotype 3 and a triple reassortant among three serotypes of reoviruses. It was grouped with recently reported reoviruses from disease cases (swine, human and feline), based on the genetic analysis of L1 and S1 partial sequences. In conclusion, two unknown cytopathogenic agents were successfully identified using modified PAN-PCR with cell control system and they were characterized in this study.

• 미생물학회지
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• 제8권1호
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• pp.1-12
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• 1970

Nucleic acid and protein biosynthese of the glucose-bleached Chlorella cells in relation to the process of the chloroplast reformation were traced, by measuring the changes in the amounts of cell constituents and nuclease activities of the cells during the greening process. The contents of RNA and protein of the glucose-bleached cells decreased significantly, shile the contents of nucleotides and amino acids of the cells increased to compared with those of the control, showing that the biosynthetic activities of RNA and protein of the cells were inhibited severely in the glucose-bleaching process. In the early greening process of the glucose-bleached Chlorella cells the contents of RNA and protein of the cells increased significantly, while the contents of nucleotides nad amino acids of the cells increased to compared with those of the control, showing that the biosynthetic activities of RNA and protein of the cells were inhibited severely in the glucose-bleaching process. In the early greening process of the glucose-bleached Chlorella cells the contents of RNA and protein of the cells increased significantly wihout any increase in the chlorophyll contents showing that the massive biosynthese of RNA and protein proceed prior to the chlorophyll bioynthesis in the cells. The phosphate contents in the DNA fraction of the glucose-bleached cells decreased, but the contents of acid-insoluble polyphosphate increased to compared with those of the control in the early greening porcess, exhibiting that the incorporation of the phosphorus from acid-insoluble polyphosphate into DNA was retarded. In the greening process of the glucose-bleached cells the ribonuclease nad deoxyribonuclease activities of the cells decreased to compared with those of the control, although the initial activities of the both enzymes in the cell were far great compared with the control. Although the initial phosphate contents in the lipid fraction of the glucose-bleached Chlorella cells were more great than the control, the phosphate contents in the lipid fraction of the cells decreased in the early greening process to compared with control, and then increased in the late developmental stages in which massive chlorophyll biosynthesis occured.

• 생명과학회지
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• 제34권8호
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• pp.588-593
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• 2024

대사경로 3,490개가 고세균 471종에 분포하는 정도를 MetaCyc database의 자료를 이용하여 분석하였다. 대사경로의 수는 고세균의 종류에 따라 13~184개가 존재하였다. 모든 고세균에 공통적으로 존재하는 대사경로는 없었으며 470종의 고세균에 UTP and CTP de novo biosynthesis와 tRNA charging의 대사경로가 존재하였다. 고세균들에 분포하는 상위 12개의 대사경로 중에서 핵산관련이 5개, 단백질관련이 5개 그리고 생체의 여러 반응에 참여하는 cofactor인 S-adenosyl-L-methionine (SAM)의 생합성 대사경로와 효소의 활성에 필수적인 번역 후 변형에 필요한 phosphopantothenate biosynthesis III (archaea)의 대사경로로 나타나 핵산과 물질대사와 관련된 단백질의 중요성을 알 수 있었다. 대사경로 보유 계통수에서 구한 distance value를 이용하여 고세균의 각 강(class)을 평균과 표준편차로 나누었을 때, 2개의 그룹과 기타로 나뉘어져 대사경로의 분포가 다양한 것으로 나타났다. 본 연구결과는 기초과학 이외에 약물개발 등에도 응용될 수 있을 것으로 기대된다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.1919-1924
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• 2015

Polymorphisms in the region of the interleukin IL-28 gene on chromosome 19 have been related with clearance of hepatitis C virus (HCV), a major human pathogen responsible for chronic hepatitis, cirrhosis and hepatocellular carcinoma. About 3% of the world's population is infected with HCV. The long-term response to therapy is influenced by many host and viral factors, and recent evidence has indicated that some host genetic polymorphisms related to IL-28 are the most powerful predictors of virological response in patients with HCV. This study assessed frequency of the IL-28 polymorphism (rs8099917) in 50 patients (39 men and 11 women) with chronic hepatitis C using ZNA probe real time PCR new method. All patients were tested for genotype of HCV and the HCV viral load. In parallel, the levels of SGOT, SGPT and ALK enzymes were assessed. Treatment using Peg-interferon alpha with ribavirin was conducted for patients and subsequently samples were collected to detect any change in viral load or liver enzyme rates. The overall frequency of the TT allele is 74%, TG allele 20% and GG allele 6% and the percent of patients who had T allele was 84%. Clear reduction in viral load and liver enzymes was reported in patients with the T allele. Especially for genotype 1 which is relatively resistant to treatment, these alleles may have a role in this decline. In conclusion, we showed that IL-28 polymorphism rs8099917 strongly predicts virological response in HCV infection and that real-time PCR with Zip nucleic acid probes is a sensitive, specific and rapid detection method for detection of SNPs which will be essential for monitoring patients undergoing antiviral therapy.

• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.735-742
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• 2013

Peptide nucleic acids (PNAs) that bind to complementary nucleic acid sequences with extraordinarily high affinity and sequence specificity can be used as antisense oligonucleotides against microRNAs, namely antagomir PNAs. However, methods for efficient cellular delivery must be developed for effective use of PNAs as therapeutic agents. Here, we demonstrate that antagomir PNAs can be delivered to hepatic cells by complementary DNA oligonucleotide and cationic liposomes containing galactosylated ceramide and a novel cationic lipid, DMKE (O,O'-dimyristyl-N-lysyl glutamate), through glycoprotein-mediated endocytosis. An antagomir PNA was designed to target miR-122, which is required for translation of the hepatitis C virus (HCV) genome in hepatocytes, and was hybridized to a DNA oligonucleotide for complexation with cationic liposome. The PNA-DNA hybrid molecules were efficiently internalized into hepatic cells by complexing with the galactosylated cationic liposome in vitro. Galactosylation of liposome significantly enhanced both lipoplex cell binding and PNA delivery to the hepatic cells. After 4-h incubation with galactosylated lipoplexes, PNAs were efficiently delivered into hepatic cells and HCV genome translation was suppressed more than 70% through sequestration of miR-122 in cytoplasm. PNAs were readily released from the PNA-DNA hybrid in the low pH environment of the endosome. The present study indicates that transfection of PNA-DNA hybrid molecules using galactosylated cationic liposomes can be used as an efficient non-viral carrier for antagomir PNAs targeted to hepatocytes.

• 미생물학회지
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• 제37권4호
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• pp.294-298
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• 2001

감염성 바이러스의 발생은 세계적인 현상으로 어린이는 물론 성인의 건강을 위협하고 있는 실정이다. 1998년 -2000년 사이에 부산지역 바이러스성 전염병 유행예측사업의 과정에서 소화기계 바이러스가 탐색되었다. 의심되는 환자의 대변 및 뇌척수액, 인후가검물에서 세포배양, Latex 응집반응, 간접면역형광항체법, 전자현미경 관찰 등을 행하여 바이러스를 확인하였다. 총 검체 중에서 바이러스의 확인 율은 12.5% 이었다. 이 과정을 통하여 3 사례의 장 adenovirus 및, 23 사례의 echovirus, 31 사례의 coxsackievirus, 36 사례의 rotavirus, 45 사례의 small round structured virus (SRSV), 7 사례의 poliovirus가 확인되었다. 확인된 주요 혈청형으로는 장 adenovirus 41형 및 echovirus 6, 9, 11, 25, 30형, coxsackievirus B2, B3, B4, B6 형 등이 탐색되었다. 각 바이러스의 월별 발생별로는 SRSV는 12월에서 다음해 4월 사이, echovirus와 coxsackievirus는 4월에서 10월 사이에, rotavirus는 1월에서 4월 사이에 각각 분리 율이 높았다. 전자현미경 관찰에서는 30-80 nm의 작은 크기의 바이러스들이 확인되었다.

• Gut and Liver
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• 제12권6호
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• pp.641-647
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• 2018

Background/Aims: Helicobacter pylori eradication rates are decreasing because of increases in clarithromycin resistance. Thus, finding an easy and accurate method of detecting clarithromycin resistance is important. Methods: We evaluated 70 H. pylori isolates from Korean patients. Dual-labeled peptide nucleic acid (PNA) probes were designed to detect resistance associated with point mutations in 23S ribosomal ribonucleic acid gene domain V (A2142G, A2143G, and T2182C). Data were analyzed by probe-based fluorescence melting curve analysis based on probe-target dissociation temperatures and compared with Sanger sequencing. Results: Among 70 H. pylori isolates, 0, 16, and 58 isolates contained A2142G, A2143G, and T2182C mutations, respectively. PNA probe-based analysis exhibited 100.0% positive predictive values for A2142G and A2143G and a 98.3% positive predictive value for T2182C. PNA probe-based analysis results correlated with 98.6% of Sanger sequencing results (${\kappa}$-value=0.990; standard error, 0.010). Conclusions: H. pylori clarithromycin resistance can be easily and accurately assessed by dual-labeled PNA probe-based melting curve analysis if probes are used based on the appropriate resistance-related mutations. This method is fast, simple, accurate, and adaptable for clinical samples. It may help clinicians choose a precise eradication regimen.