• Journal of Microbiology and Biotechnology
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• 제18권4호
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• pp.624-630
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• 2008

Terminal restriction fragment length polymorphism (T-RFLP) is a method that has been frequently used to survey the microbial diversity of environmental samples and to monitor changes in microbial communities. T-RFLP is a highly sensitive and reproducible procedure that combines a PCR with a labeled primer, restriction digestion of the amplified DNA, and separation of the terminal restriction fragment (T-RF). The reliable identification of T-RF requires the information of nucleotide sequences as well as the size of T-RF. However, it is difficult to obtain the information of nucleotide sequences because the T-RFs are fragmented and lack a priming site of 3'-end for efficient cloning and sequence analysis. Here, we improved on the T-RFLP method in order to analyze the nucleotide sequences of the distinct T-RFs. The first method is to selectively amplify the portion of T-RF ligated with specific oligonucleotide adapters. In the second method, the termini of T-RFs were tailed with deoxynucleotides using terminal deoxynucleotidyl transferase (TdT) and amplified by a second round of PCR. The major T-RFs generated from reference strains and from T-RFLP profiles of activated sludge samples were efficiently isolated and identified by using two modified T-RFLP methods. These methods are less time consuming and labor-intensive when compared with other methods. The T-RFLP method using TdT has the advantages of being a simple process and having no limit of restriction enzymes. Our results suggest that these methods could be useful tools for the taxonomic interpretation of T-RFs.

• 한국미생물·생명공학회지
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• 제26권2호
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• pp.117-121
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• 1998

김치로부터 분리한 Lactobacillus plantarum bacteriophage SC 921은 M.O.I가 0.2일 경우 용균효과가 빠르게 진행됨을 알 수 있었고, SDS-PAGE를 실시하여 phage particle protein을 조사해 본 결과 4개의 major protein으로 구성되어 있는데 이들은 각각 48, 34, 32, 29 kDa으로 구성되어 있다. Exo III로 30분간 반응시킨 후 S1 nuclease를 처리하여 DNA의 형태를 조사해 본 결과 intact DNA는 linear form의 double strand를 유전전달 물질로 가지고 있었다. 제한효소에 대한 절단 효과를 조사한 결과, Sma I에 대해서 1개, Xba I, Cla I, Kpn I, EcoRI에 대해서 각각 2, 4, 5, 6개의 절단부위를 가지고 있으며, Hind III에 대해서는 절단부위가 매우 많은 것을 알 수 있었다. Hind III를 이용하여 intact DNA의 genome size를 측정해본 결과 약 66.5 kbp정도였다. 위의 실험결과와 restriction enzyme mapping을 통해 기존에 알려진 bacteriophage B2와 비교해본 결과 숙주 균주는 같으나 단백질적인 구조나 유전전달물질로 본 구조는 서로 다름을 알 수 있었다.

• 미생물학회지
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• 제42권1호
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• pp.26-33
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• 2006

생물학적 질소 제거(Biological nitrogen removal; BNR) 시스템의 효율적인 처리 공정을 이재하기 위하여 질산화 반응조 내 세균 군집 구조를 16S rRNA 유전자의 PCR 및 terminal restriction fragment length polymorphism (T-RELP)방법을 이용하여 분석하였다. 본 연구에서 사용한 BNR 시스템은 국내에서 비교적 많이 적용되고 있는 부상여재를 이용한 고도처리 시스템, Nutrient Removal Laboratory 시스템, 반추기법을 이용한 영양염류 처리 Sequencing Batch Reactor (SBR)시스템이었고, 실험 결과 모든 시료에서 암모니아 산화 세균과 $\beta-proteobacteria$에 해당되는 말단 단편을 확인할 수 있었다. 암모니아 산화세균 군집에서 유래된 말단 단편의 염기서열을 분석한 결과 SBR공정에서는 Nitrosomonas와 Nitrosolobus에 속하는 군집 이 우점종임을 확인할 수 있었다. 그러나 다른 두 공정들에서는 $\beta-proteobacteria$에 속하는 미배양 균주와 Cardococcus australiensis와 염기서열 유사도가 높은 군집이 우점하였다. 또한, 암모니아산화 세균군집을 분석한 결과, SBR 공정이 암모니아 산화세균의 농화 배양에 가장 효과적인 것으로 나타났다. 이러한 결과는 각 BNR 시스템에 동일한 폐수가 유입되었음에도 불구하고 서로 다른 세균 군집 구조를 형성하고 있음을 의미한다.

• 생명과학회지
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• 제8권2호
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• pp.126-130
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• 1998

Vibrio unlnificus ATCC 27562의 16S rRNA 유전자를 PCR법과 제한효소절단법으로 분석 하여 얻은 결과는 다음과 같다. 1. 고안된 한쌍의 primer로 PCR을 시행하여 얻은 산물은 약 1.3Kb 였다. 2. PCR산물을 여섯가지의 제한 효소로 절단하여 얻은 단편들은 아래와 같다. BamH I: 어떤 restriction fragment도 만들지 않았다. Alu I : 약 400bp와 200bp의 두가지 fragment를 생산하였다. Sau3A I : 약 70bp에서 450bp 사이에 세가지 fragment를 생산하였다. Hind III : 약 800bp와 500bp의 약간 큰 두가지 fragment를 생산하였다. Sal I : 약 500bp와 750bp의 두가지 fragment를 생산하였다. Sma I : 약 800bp와 470bp의 두가지 fragment를 생산하였다.

• 한국안전학회지
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• 제31권3호
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• pp.116-122
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• 2016

With the changes of industrial structure, contents and types in hazardous and dangerous works have been changed considerably. However, the hazardous and dangerous works by defined "Regulation for the hazardous and dangerous work employment restriction" and "Special education for safety and health"have not been amended over twenty years. This study aimed to identify the recent trends of the works by analyzing the death accidents cases from 2004 to 2013 and to present the management methods about future hazardous and dangerous works. The results showed that amount of 1,972 cases among 11,513 death accidents were equivalent to the works presented by "Regulation for the hazardous and dangerous work employment restriction". The amount of death accidents in 'Work of using construction equipment following construction machinery management act' was biggest among the death accidents cases and that of 'Work of handling pressure vessels following high-pressure gas safety control act' didn't show up. For the works in "Special education for safety and health"amount of 1,650 death accidents cases were equivalent. The amount of death accidents in 'Work involving a crane with a capacity of 1 ton or more or work which is carried out with a crane or hoist with a capacity of less than 1 ton in a workplace having at least 5 such machines' presented by "Special education for safety and health"was biggest. Also, death accidents case didn't occurred in three works presented by "Special education for safety and health". It was analyzed that works with low death accidents cases should be needed to study thoroughly the whole disaster research involving nonfatal accidents. Through this study, it was expected that regulation can be operated practically in the industrial field. Also, it is considered to increase

• Journal of Microbiology
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• 제43권5호
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• pp.417-423
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• 2005

In this study, the nematode-trapping fungus, Monacrosporium sphaeroides, was transformed with a plasmid harboring the hygromycin B phosphotransferase gene, via restriction enzyme-mediated integration (REMI). Frequencies of up to 94 transformants ${\mu}g^{-1}$ per linearized plasmid DNA were obtained by optimizing the PEG concentration, as well as the category and quantity of the added restriction enzyme. $90\%$ of the transformants were determined to be stable for drug resistance when 20 randomly selected transformants were tested. Southern analyses revealed that the transforming DNA was integrated into the M. sphaeroides genome either with or without rearrangement. Five mitotic stable mutant strains were obtained using this approach, all of which had been altered with regard to sporulation capacity and pathogenicity toward nematodes. Southern blot analyses of the five mutants revealed that foreign plasmid DNA had integrated into the genome. Three of the mutants, Tms2316, Tms3583 and Tms1536, exhibited integration at a single location, whereas the remaining two, Tms32 and Tms1913, manifested integration at double or multiple locations. Our results suggest that the transformation of M. sphaeroides via REMI will facilitate insertional mutagenesis, the functional analysis of a variety of genes, and the tagging or cloning of genes of interest.

• Journal of Preventive Veterinary Medicine
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• 제42권4호
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• pp.163-170
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• 2018

The cost-effectiveness of foot-and-mouth disease (FMD) control strategies was evaluated using a simulation model fitted to the 2010/11 FMD epidemic in the city of Andong, Republic of Korea. Seven FMD-control strategies were evaluated with respect to the direct cost of a FMD-control strategy, such as slaughtering, movement restriction, and vaccination. All the strategies included pre-emptive slaughtering, movement restriction, and vaccination, but the levels of each control option were different. The simulated median cost of the baseline FMD-control strategy (three kilometers of pre-emptive slaughtering area, 100 days of movement restriction and vaccination of all FMD-susceptible animals in the study area) was estimated to be USD 99.7 million. When a five kilometer vaccination area was applied (with the other control measures being the same as the baseline strategy), the simulated median cost was reduced to USD 81.1 million from USD 99.7. The simulated median costs were USD 107.6 million for a five kilometer radius slaughtering area and USD 168.8 million for 60 days of movement restriction. The FMD-control strategy cost decreased with increasing number of farms depopulated per day. The probability of passive surveillance being effective or the probability of the successful implementation of movement restrictions were increased. Cost-effectiveness analysis is a suitable tool for evaluating the financial consequences of FMD-control strategies by comparing the cost of control strategies for a specific area.

• Journal of Korean Neurosurgical Society
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• 제66권5호
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• pp.562-572
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• 2023

Objective : Bevacizumab is a feasible option for treating cerebral radiation necrosis (RN). We investigated the clinical outcome of RN after treatment with bevacizumab and factors related to the initial response and the sustained effect. Methods : Clinical data of 45 patients treated for symptomatic RN between September 2019 and February 2021 were retrospectively collected. Bevacizumab (7.5 mg/kg) was administered at 3-week intervals with a maximum four-cycle schedule. Changes in the lesions magnetic resonance image (MRI) scans were examined for the response evaluation. The subgroup analysis was performed based on the initial response and the long-term maintenance of the effect. Results : Of the 45 patients, 36 patients (80.0%) showed an initial response, and eight patients (17.8%) showed delayed worsening of the corresponding lesion. The non-responders showed a significantly higher incidence of diffusion restriction on MRI than the responders (100.0% vs. 25.0%, p<0.001). The delayed worsening group showed a significantly higher proportion of glioma pathology than the maintenance group (87.5% vs. 28.6%, p=0.005). Cumulative survival rates with sustained effect were significantly higher in the groups with non-glioma pathology (p=0.019) and the absence of diffusion restriction (p<0.001). Pathology of glioma and diffusion restriction in MRI were the independent risk factors for non-response or delayed worsening after initial response. Conclusion : The initial response of RN to bevacizumab was favorable, with improvement in four-fifths of the patients. However, a certain proportion of patients showed non-responsiveness or delayed exacerbations. Bevacizumab may be more effective in treating RN in patients with non-glioma pathology and without diffusion restriction in the MRI.

• 제3의학
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• 제2권1호
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• pp.25-33
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• 1997

In Sasang medicine, humen are classified into four constitutions which are Taeyang, Soyang. Taeum and Soum. Depending on each different constitution, the clinical and pharmacological application for the same disease might be different. In this study, genomic DNA of different constitutions(Taeum, Soyang and Soum) were analyzed by Restriction Fragment Length Polymorphism(RFLP) to provide scientific and objective references for Sasang classification. The DNA polymorphism for each constitution detected as differences in the length of DNA fragments, after digestion with restriction enzyme Hae III, was investigated using YNH24 as DNA probe. The allele size of Taeum, Soyang and Soum group detected by YNH24 ranged from 1.3 to 3.8 kb, 1.5 to 3.9 kb and 1.3 to 4.6 kb, respectively. However, the allele size distribution of YNH24 loci of different constitutions was shown to be too variable to be classified as 3 different constitution groups investigated. For further study, it is suggested that the number of each constitution samples for RFLP analysis should be increased and statistical analysis of the allele size distribution should be carried out.

• 소성∙가공
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• 제25권4호
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• pp.268-274
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• 2016

In the automotive seat industry, the use of a fine blanking press is important for manufacturing of high precision products. Among them, a gear part which is a main component of an automotive seat recliner is generally manufactured by fine blanking press. However, the use of conventional mechanical press has been increasing in manufacture of gear part because of low productivity of fine blanking press. In this study, new forming process is suggested to fabricate the gear part with high precision by using mechanical press. The effect of flow restriction die (FRD) which has the restriction of blank edge on dimensional accuracy is investigated by FE-analysis. FE-analysis results for different conditions of FRD indicated that FRD has high dimensional accuracy with the lowest roll-over and the highest perpendicularity of gear part. After application to fabrication of the gear part using mechanical press, the measured dimensional characteristic was compared with the required specification of final product. In addition, results of the performance test showed that the product fabricated by developed process satisfied the required strength and durability. The results show that the suggested forming process by using FRD and mechanical press can replace fine blanking on the viewpoint of dimensional accuracy and productivity.