• Journal of Animal Science and Technology
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• 제47권3호
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• pp.465-474
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• 2005

A two-step broad-range PCR method detecting gram-negative bacteria at the level as low as 2 CFU was developed by using primers of GNFI and GNRI and then semi-nested primer of GNF2 and GNRI. The nucleotide sequences of the primers were determined based on l6S rRNA gene. The DNA fragments of 1173 bp and 169 bp were amplified in one-step PCRs with primer sets of GNFI-GNRI and GNF2-GNRl, respectively, using template DNA from seven strains of gram-negative bacteria including Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Pseudomonas spp., and Acinetobacter baumaii but not from Achromobacter lyticus, Alca/igens faecalis, and five strains of gram-positive bacteria. DNA fragments of 180 bp were amplified from LTLT-pasteurized milk and UHf-pasteurized milk in the two-step PCR. The DNA fragments were amplified from LTLT-pasteurized milk which was added with Pseudomonas j/uorescens and subsequently heated at 65 $^{\circ}C$, 80 $^{\circ}C$, and 100 $^{\circ}C$ for 30 min but they were not amplified from the milk autoclaved at 121$^{\circ}C$ for 15 min. It was suggested in PCR that Pseudomonas fluorescens heated at 65 $^{\circ}C$ for 30 min in milk was more sensitive to DNase treatment than viable bacteria.

• Parasites, Hosts and Diseases
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• 제54권4호
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• pp.393-397
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• 2016

Low parasitemic condition in malaria remains a diagnostic challenge; as the available diagnostic methods failed to detect. Currently, hemozoin (Hz) pigment is gaining attention in the diagnosis of malaria. The major drawback is ease of detection of Hz in routine practice. A pilot study was conducted to evaluate the role of Hz pigment and to compare the performance of quantitative buffy coat assay (QBC) and PCR in such conditions. Clinically suspected cases of malaria were examined by both Giemsa stain and immunochromatographic test (ICT). Samples positive by ICT and negative by Giemsa stain were further examined by nested PCR targeting 18S rRNA and QBC for the presence of malaria parasites and pigments. Thirty blood samples fulfilled the inclusion criteria out of which 23 were Plasmodium vivax (Pv), 4 Plasmodium falciparum (Pf), and 3 mixed (Pv and Pf) by immunochromatographic test. Twenty-one out of 30 (70%) were positive by nested PCR in comparison to 25/30 (83%) by QBC. Samples containing both malaria parasites and Hz pigment by QBC completely showed concordance with the PCR result. However, 61% of total samples containing only Hz pigment were observed positive by PCR. Hz pigment remains an important tool for malaria diagnosis. Identification of leukocytes containing pigments by QBC not only indicates recent malarial infections but also puts light on severity of the disease. QBC assay is a rapid, highly sensitive, and cost-effective method to detect malaria parasites and Hz pigment especially in low parasitemic conditions.

• 대한바이러스학회지
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• 제29권1호
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• pp.23-31
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• 1999

Hantavirus is a genus of the Bunyaviridae family causing two serious diseases, hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). Puumala virus is a member of hantavirus originally found in Europe, and its natural reservoir is Clethrionomys glareolus. It is also associated with the human disease nephropathia epidemica, a milder form of HFRS. To identify the hantaviruses in bats, bats were collected from Jeong-Sun, Won-Joo, Chung-Ju and Hwa-Cheon area in Korea, and nested RT-PCR was performed with serotype specific primer from M segment. Interestingly, Puumala virus was detected in bats (Rhinolophus ferrum-equinum) only from Won-Joo. The 327 bp nested RT-PCR product, was sequenced. The sequence database search indicates that the sequence is homologous to the published sequence of Puumala viruses. The sequence similarities were ranged from 71% to 97%. The highest sequence similarity was 97% with Puumala virus Vranicam strain, and the lowest was 71% with Puumala virus K27 isolate. Puumala virus Vranicam strain was isolated from a bank vole (Clethrionomys glareolus) in Bosnia-Hercegovina. Puumala virus K27 was isolated from human in Russia. This analysis confirms that bats (Rhinolophus ferrum-equinum) in Korea are natural reservoir of Puumala virus.

• 대한의생명과학회지
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• 제27권4호
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• pp.255-263
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• 2021

Human Astrovirus (HuAstV) is an important gastrointestinal pathogen that is frequently reported worldwide. Monitoring of contaminated groundwater has been suggested since HuAstV is transmitted through the fecal-oral route. This study developed a test method based on conventional reverse transcription (RT)-nested polymerase chain reaction (PCR) that involves SL^® non-specific reaction inhibitor for unknown non-specific amplification taking place in the groundwater environment. An optimal method for detecting HuAstV in groundwater sample through analysis and comparison against conventionally reported method was also suggested. The developed method enabled the production of nested PCR amplicon of 630 nt, which is a sufficient length for similarity analysis based on sequencing and genotyping. Amplicons suspected to be HuAstV were amplified in two out of the twenty groundwater samples collected in Korea, presenting 99.77% and 99.73% similarity against HuAstV 1 strain lhar/2011/kor (JN887820.1) in sequencing, respectively. These amplicons were identified as HuAstV 1.

• 미생물학회지
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• 제42권1호
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• pp.19-25
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• 2006

치아우식중의 원인균 중 하나인 Streptococcus mutans를 종 수준에서 동정할 수 있는 중합효소연쇄반응 프라이머를 개발하기 위하여 본 연구를 시행하였다. 표준균주인 S. mutans ATCC $25175^T$및 본 연구에서 이용된 S. mutans 균주들의 16S rRNA 유전자 핵산염기서열을 바탕으로 S. mutans 종-특이 중합효소연쇄반응 프라이머(ChDC-SmF2와 ChDC-SmR2)를 설계 및 제작하였다. 프라이머의 특이도는 S. mutans 11균주와 구강 내 존재하는 12세 균 종(22균주)을 대상으로 실시하였다. 프라이머의 민감도는표준균주인 S. mutans ATCC $25175^T$의 유전체 DNA를 추출하여 실시하였다. 프라이머의 특이도 실험결과 10균주의 S. mutans 유전체 DNA에서만 종-특이 중합효소 연쇄반응 산물이 증폭되었고, 다른세균종의 유전체 DNA에서는 증폭되지 않았다. 또한 감수성 실험 결과 본 연구에서 사용된 프라이머는 direct PCR에 의해 S. mutans ATCC $25175T\^T$ 유전체 DNA 100 pg까지 검출 할 수 있었다. 또한 27F와 1492R 프라이머로 16S rDNA를 먼저 증폭한 다음, 이 증폭물 10배 회식한 것을 표적으로 해서 nested PCR을 시행한 결과 S. mutans ATCC $25175^T$ 유전체 DNA를 2 fg까지 검출할 수 있었다. 이상의 결과를 종합할 때, ChDC-SmF2와 ChDC-SmR2 프라이머들은 S. mutans 균주 유전체 DNA에 대한 높은 민감도를 가지고 있으며, 종-특이적으로 동정 및 검출하는 데 이용될 수 있을 것으로 생각된다.

• 대한임상검사과학회지
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• 제47권2호
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• pp.83-89
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• 2015

결핵(Mycobacterium tuberculosis, MTB) 감염은 아직까지 전 세계에서 높은 유병률과 사망의 주요 원인이 되고 있으며 비정형 결핵(nontuberculous mycobacteria, NTM)은 최근 후천성 면역결핍증(AIDS)이나, 종양, 이식 등으로 면역력이 저하된 환자들의 임상 검체에서 분리빈도가 증가함에 따라 분리 균주의 임상적 의의가 중요시 되고 있다. 이에 항산균 염색을 이용한 객담 도말검사는 결핵균과 비정형 결핵균을 구별할 수 없다는 제한점이 있고, 균 분리배양검사는 시간이 오래 걸린다는 단점이 있어, 본 연구에서는 이러한 제한점을 가진 기존의 검사법을 대신하여 분자생물학적 방법인 중합효소 연쇄반응(polymerase chain reaction, PCR)을 이용하여 균 분리배양 검사와 비교하여 보았다. Mycobacteria를 동정하는데 항산균 염색과 3% ogawa 배지를 이용하였고, 균 분리배양 후 M. tuberculosis를 확인하기 위해서 niacin test를 실시한 결과 집락의 DNA를 추출하여 PCR후 동정된 M. tuberculosis와 niacin 양성이 일치함을 확인할 수 있었다. 또, 이 실험에서 항산성균 염색이 2+ 이상인 객담검체와 집락검체 각각에서 DNA를 추출하여 결핵균을 동정하는 방법으로 M. tuberculosis complex에 특징적으로 존재하는 insertion sequence (IS) 6110의 특정부위인 547 bp와 285 bp 부분을 증폭한 two-tube nested polymerase chain reaction을 시행하였고, 비정형 결핵균 동정법으로는 mycobacteria에 공통적으로 존재하는 rpoB 유전자 중 일부인 360 bp 부분을 증폭한 후, 제한효소 Msp I을 첨가 PCR-restriction fragment length polymorphism (RFLP)을 시행하였으며, 결핵균과 비정형 결핵균 모두 동정율에 거의 차이가 없었다. 1+인 경우는 객담검체에서 PCR한 결과가 31.2%에서 집락검체의 PCR한 결과 93.7%까지 결핵균과 비정형결핵균의 동정율이 높아졌고, trace인 경우 객담검체에서 PCR 결과가 2%에서 집락검체에서 PCR한 결과가 97.9%까지 결핵균과 비정형 결핵균의 동정율을 높일 수 있었다. 이 실험에서 항산성균 염색 1+이하 일때 객담검체와 집락검체로 PCR을 실시하면 결핵균과 비정형 결핵균의 동정율에 차이가 있고, 배양만으로는 결핵균의 동정은 가능하지만 비정형 결핵균의 동정이 가능하지 않으므로 배양검사와 PCR 검사 모두를 병행하므로써 보다 신속하고 정확한 검사결과를 내는데 도움 될 것이다.

• 식물병연구
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• 제17권3호
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• pp.376-380
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• 2011

P. syringae pv. tomato는 토마토에서 bacterial speck병을 일으키는 종자전염 세균으로, 감수성 품종에서 주로 발병하여 경제적으로 큰 손실을 입힌다. 따라서 P. syringae pv. tomato는 한국을 비롯한 많은 나라에서 식물 검역대상 세균으로 지정하여 관리되고 있다. 본 연구에서 우리는 토마토 종자로부터 PCR을 이용하여 Pst를 검출할 수 있는 방법을 개발하였다. P. syringae pv. tomato의 hrpZ 유전자에서 특이적인 프라이머를 개발하였다. 개발된 프라이머는 P. syringae pv. tomato에서만 501 bp 크기의 특이적 DNA를 증폭하였으며, P. syringae pv. glycinea, P. syringae pv. maculicola, P. syringae pv. atropurpurea, P. syringae pv. morsprunorum와 같은 다른 토마토 세균병원균과 P. syringae pathovar 균주들에서는 증폭되지 않았다. Nested PCR 프라이머를 이용한 PCR에서도 오직 P. syringae pv. tomato에서만 119 bp 크기의 특이적 DNA가 증폭되었고, 토마토 종자에서 P. syringae pv. tomato을 정확하고 민감하게 검출하였다. 본 연구는 현재까지 사용되고 있는 Pst의 검출방법의 민감도를 비교한 최초의 보고로 본 연구에서 개발된 PCR방법들은 토마토 종자에서 Pst을 검출하는 매우 유용한 방법으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제27권3호
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• pp.471-479
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• 2017

White spot syndrome virus (WSSV) is a major threat to the shrimp farming industry and so far there is no effective therapy for it, and thus early diagnostic of WSSV is of great importance. However, at the early stage of infection, the extremely low-abundance of WSSV DNA challenges the detection sensitivity and accuracy of PCR. To effectively detect low-abundance WSSV, here we developed a pre-amplification PCR (pre-amp PCR) method to amplify trace amounts of WSSV DNA from massive background genomic DNA. Combining with normal specific PCR, 10 copies of target WSSV genes were detected from ${\sim}10^{10}$ magnitude of backgrounds. In particular, multiple target genes were able to be balanced amplified with similar efficiency due to the usage of the universal primer. The efficiency of the pre-amp PCR was validated by nested-PCR and quantitative PCR, and pre-amp PCR showed higher efficiency than nested-PCR when multiple targets were detected. The developed method is particularly suitable for the super early diagnosis of WSSV, and has potential to be applied in other low-abundance sample detection cases.

• Journal of Microbiology
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• 제39권3호
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• pp.226-228
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• 2001

Human lymphotropic herpesvirus is known to be a major pathogen associated with various diseases in bone marrow transplantation (BMT) recipients. A multiplex nested-polymerase chain reaction (PCR) method was developed for the simultaneous detection of human lymphotropic herpesviruses, including Ebstein-Barr virus (EBV), cytomegalovirus (CMV), and human herpesvirus 6 variants A and B (HHV6-A, HHV6-B). To demonstrate the usefulness of multiplex PCR for the analysis of clinical samples, peripheral blood mononuclear cells and serum from BMT recipients were analysed. The results skewed that a clear detection could be made between EBV, HCMV and HHV-6. This multiplex PCR assay is an efficient and cost-effective approach to the analysis of large numbers of samples to determine the epidemiological importance of EBV HCMV and HHV-6.

• The Plant Pathology Journal
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• 제21권1호
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• pp.55-58
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• 2005

In order to diagnose and differentiate jujube witches' broom (JWB) phytoplasma rapidly, oligonucleotide primer pair, 16Sr(V) F/R, for polymerase chain reactions (PCRs) was designed on the basis of 16S rRNA sequences of JWB phytoplasma. The PCR employing phytoplasma universal primer pair P1/P7 consistently amplified DNA in all tested phytoplasma isolates. But no phytoplasma DNA was detected from healthy jujube seedlings. The nested PCR, the primer pair 16S(V) F/R, about 460 bp fragment, amplified DNA in all tested JWB and related phytoplasmas including ligustrum witches' broom phytoplasma of the 16S rRNA group V, but no DNA amplification was detected from other phytoplasma strains such as groups 16SrI (Aster yellows) and 16SrXII (Stolbur group) in which mulberry dwarf phytoplasma and chrysanthemum witches' broom phytoplasma belong to, respectively. The same results were obtained from both Korean and Chinese isolates of JWB phytoplasma. Nested-PCR using phytoplasma universal primer pair P1/P7 and 16SrV group-specific primer pair 16S(V) F/R could detect group V phytoplasmas rapidly and easily, in particular JWB phytoplasma.