• The Plant Pathology Journal
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• v.18 no.1
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• pp.12-17
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• 2002

For the molecular detection of Sweet potaio feathery mottle virus (SPFMV) from diseased sweet potato plants, reverse transcription and polymerase chain reaction (RT-PCR) was performed with the use of a set of virus-specific primers to amplify an 816 bp product. The viral coat protein gene was selected for the design of the primers. No PCR product was amplified when Turnip mosaic virus, Potato vims Y or Cucumber mosaic virus were used as template in RT-PCR with the SPFMV-specific primers. The lowest concentration of template viral RNA required for detection was 10 fg. The vim was rapidly detected from total nucleic acids of leaves and roots from the virus-infected sweet potato plants as well as from the purified viral RNA by the RT-PCR. Twenty-four sweet potato samples were selected and analyzed by RT-PCR and restriction fragment length polymorphism (RFLP). RFLP analysis of the PCR products showed three restriction patterns, which resulted in some point mutations suggesting the existence of quasi-species for the vims in the infected sweet potato plants.

• The Plant Pathology Journal
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• v.25 no.1
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• pp.21-25
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• 2009

Jujube trees infected with phytoplasma exhibit symptoms of typical witches' broom, such as yellowing, abnormally small leaves, short internodes and proliferation of shoots. A 1.2 kb fragment of the 16S rDNA from jujube phytoplasma was generated by R16F2n/R16R2 primer pair from earlier amplified P1/P7 PCR products of cloned jujube witches' broom phytoplasmas. Enzymatic restriction fragment length polymorphism (RFLP) and sequence analysis of 16S rDNA revealed that the jujube tree was infected with 16S rDNA I and V groups of phytoplasmas. Extensive comparative analyses of restriction enzyme profiles from Alu I, Hha I, Msp I, and Rsa I clearly classified the two into different phytoplasma groups. The phylogenie analyses based on 16S rDNA showed that the similarity of the two different clones was 87.5%. This is the first report of a mixed phytoplasmal infection in a single jujube tree.

• Journal of Veterinary Clinics
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• v.27 no.2
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• pp.130-135
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• 2010

Malassezia (M.) is a member of normal mycobiota in warm-blooded vertebrates. Increased humidity is likely to be crucial in this infection. We studied the proportion of the species infected in dog during summer of Korea. Fifty samples were analyzed by PCR-RFLP and direct sequencing from June 2006 to October 2006. The study showed that lipid-dependent species was main pathogen (M. furfur; 86%, M. obtusa; 10%) while M. pachydermatis (4%) has only small portion. This result suggests that Malassezia infection has endemic characters that can be affected by the climate (temperature and humidity) in dogs.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.15-21
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• 2003

Two microbial communities of activated sludge in the same municipal wastewater, but treated with different systems, were studied and compared using molecular microbiological approaches. The bacterial 16S rDNA sequences from 124 clones were analyzed, however, the majority of them were not closely related to any known species, and found to belong to 8 different phylogenetic groups and 3 different unidentified groups. The relative frequencies of each group were similar between the two microbial communities. Fingerprinting using terminal restriction fragment length polymorphism (T-RFLP) showed that the putative Nitrospira-related populations were more diverse and quantitatively higher in the KNR process system than in the other system using a conventional activated sludge process. The relationship between the bacterial community composition and the higher removal efficiency of nitrogen and phosphorus in the KNR process is discussed.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.599-606
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• 2004

Gram-positive antagonistic bacilli were isolated from agricultural soils for possible use in biocontrol of plant pathogenic fungi, Fusarium oxysporum, Rhizoctonia solani, and/or Pythium ultimum. Among the 65 antagonistic Gram-positive soil isolates, 22 strains were identified as Bacillus species by 16S rDNA sequence analyses. Four strains, including DF14, especially exhibited multiple antagonistic properties against the three damping-off fungi. Genotypic properties of the Bacillus isolates were characterized by rapid molecular fingerprinting methods using repetitive extragenic palindromic-PCR (REP-PCR), ribosomal intergenic spacer-length polymorphisms (RIS-LP), 16S rDNA PCR-restriction fragment length polymorphisms (PCR-RFLP), and strain-specific PCR assays. The results indicated that the REP-PCR method was more valuable than the RIS-LP and 16S rDNA PCR-RFLP analyses as a rapid and reliable approach for bacilli typing and identification. The use of strain-specific primers designed based on 16S rDNA sequence comparisons enabled it to be possible to selectively detect a strain, DF14, which is being used as a biocontrol agent against damping-off fungi.

• Animal Systematics, Evolution and Diversity
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• v.13 no.1
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• pp.29-36
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• 1997

한국산 기름종개속 어류중 Cobitis taenia complex의 집단간 유전적 차이에 따른 종 분화 여부를 밝히고자 6개 집단을 대상으로 mitochondrial DNA(mtDNA)의 RFLP분석을 실 시하였다. C. taenia complex mtDNA를 10개의 6-base cutting 제한효소로 처리한 다음 그 절편 양상을 비교, 분석한 결과 6개 집단 공히 mtDNA 의 전체 genome 크기는 약 17.0$\pm$ 0.5Kbp였으며 공동절편수(F)에서 C. t. taenia 2개집단과 C. t. stria와 C. t. lutheri 4개 집단 간의 F값은 평균 0.263으로 차이가 있었으나, C. t. striata 와 C. t. lutheri 사이는 F=0.569로 가깝게 나타났다. 염기치환율 (p)에 있어 C. t. taenia는 C. t. striata 및 C. t. lutheri와 평균 p=0.082로 뚜렷한 종간차이를 보였으나, C. t. striata와 C. t. lutheri 집단들은 p=0.033으로 매우 가까운 유사성을 나타내었다. MtDNA 분석결과 C. taenia complex 중 C. t. taenia는 완전히 종분화가 이루어진 별종으로, C. t. striata와 C. t. lutherisms 아직 종수준의 분화가 이루어지지 않은 아종으로 분류함이 타당하다고 사료된다.

• Toxicological Research
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• v.18 no.3
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• pp.233-240
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• 2002

In view of the effect of $\beta_2$-Adrenergic receptors ($\beta_2$-AR) as a risk factor for essential hypertension, we investigated the Fnu4HI and MnlI RFLPs of $\beta_2$ -AR gene in the Korean patients with essential hypertension and normal controls. There were no significant differences in the allele and genotype of these polymorphisms between normotensive and essential hypertensive subjects. In ethnic comparison, the allele frequencies of these three sites contained Nde I RFLP reported the association with essential hypertension in Korean population previously, were very different from those of other ethnic populations studied. The significant linkage disequilibrium was detected only in hypertensive group between Nde I and Fnu4HI sites. The Fnu4HI RFLP was also significantly associated with plasma triglyceride (TG) level. Therefore, our results suggest that the significant association between Fnu4HI variation in the human $\beta_2$-AR gene and plasma TG level may reflect the potential role of human $\beta_2$-AR gene as one of the genetic components for cardiovascular risk.

• The Journal of the Korean Society for Microbiology
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• v.35 no.1
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• pp.49-60
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• 2000

ITSI-5.8S-ITSII rDNA region was amplified from the reference strains and clinical isolates with ITS1 and ITS4 primers. These primers amplified DNA fragments of 550 bp in Microsporum audouinii and Trichophyton violaceum, 700 bp in Microsporum gypseum, Trichophyton mentagrophytes, Trichophyton rubrum, and Trichophyton tonsurans, and 750 bp in Microsporum ferreugineum and Microsporum canis. The restriction enzyme patterns of PCR products digested with 13 restriction enzyme including PstI were distint among the genera, whereas identical in the same species. Examination of the ITS (Internal Transcribed Spacers)1 nucleotide sequence revealed that there was the genetic difference in each genera and species. Phylogenetic relationship among each species showed that the Trichophyton mentagrophytes was more closely related Trichophyton tonsurans than Trichophyton rubrum, and Microsporum gypseum was less related than Microsporum spp..

• BMB Reports
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• v.29 no.5
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• pp.442-447
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• 1996

Mutations in codon 12, 13 and 61 of one of the three ras genes, H-ras, K-ras and N-ras, convert these genes into active oncogenes. The presence of H-ras gene mutations have important prognostic implications in various cancers. In this study, the H-ras gene mutations were investigated by two-step PCRRFLP in patients with bladder and stomach cancer. For the control experiments, T24 and SK2 cell lines were used. In a total of 36 bladder cancer patient cases, five (13.9%) mutations were found by this method. Of these, point 12 mutations were two (5.6%) cases and point 61 mutations were three (8.3%) cases. On the other hand, H-ras mutation was not found in 29 cases of stomach cancer. The results of the mutated H-ras gene confirmed by direct sequencing analysis were correlated well with PCR analysis. From the sensitivity test, the H-ras mutation was found to have about 0.2% of mutated DNA mingled in normal DNA. In conclusion, the H-ras mutation has a higher clinical Significance in bladder cancer than stomach cancer. Moreover the two-step PCR-RFLP method is sensitive, rapid and relatively simple for clinical work in detecting H-ras point mutations.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.1093-1100
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• 2013

Background: p53 gene variants i.e. 16 bp duplication in intron 3, Arg72Pro in exon 4 and G>A in intron 6 have been reported to modulate susceptibility to various malignancies. Therefore, the present study evaluated the role of these p53 polymorphisms in oral cancer susceptibility in a population from Gujarat, West India. Method: Genotype frequencies at the three p53 loci in 110 controls and 79 oral cancer cases were determined by the PCR-RFLP method. Results: Heterozygous individuals at exon 4 showed protection from developing oral cancer. Homozygous wild and heterozygous individuals at intron 3 and those heterozygous at exon 4 in combination appeared to be at lowered risk. Furthermore, carriers of the 16 bp duplication allele at intron 3, proline allele at exon 4 and G allele at intron 6 were protected from oral cancer development. Conclusion: p53 polymorphisms, especially Arg72Pro in exon 4 could significantly modify the risk of oral cancer development in Gujarat, West Indian population.