• Korean Journal of Environmental Agriculture
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• v.36 no.4
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• pp.241-248
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• 2017

BACKGROUND: RNA interference (RNAi) eliminates or decreases gene expression by disrupting the target mRNA or by interfering with translation. Recently, RNAi technique was applied to generate new crop traits which provide protection against pests. To establish the environmental risk assessment protocol of RNAi LMO in lab scale, we developed dsRNA expression system using E. coli and tested acute oral toxicity assay to honey. METHOD AND RESULTS: The dsRNA expression vector, L4440, was chosen and cloned 240 bp of Snf7 and GFP gene fragment. To develop the maximum dsRNA induction condition in E. coli, we tested induction time, temperature and IPTG concentration in media. To estimate the risk assessment of dsRNA to honey bee, it has been selected and cultured with dsRNA supplement for 48 hours according to OECD guideline. As a result, the optimum condition of dsRNA induction was $37^{\circ}C$, 4 hours and 0.4 mM IPTG concentration and the difference between Snf7 and GFP dsRNA molecules from E. coli was not significant in survival and behavior to honey bee. Furthermore, blast search results indicated that effective match of predicted dsRNA fragments were not existed in honey bee genome. CONCLUSION: In this study, we developed and tested the acute oral toxicity of dsRNA using E. coli expression system to honey bee.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.3
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• pp.191-198
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• 2005

In order to optimize tissue culture conditions for genetic transformation of orchardgrass, the effects of culture medium supplements on tissue culture responses were investigated with mature seeds of 3 cultivars, 'Frode'. 'Roughrider' and 'Frontier' as explant tissues. Callus induction medium containing 3mg/L 2,4-D or 3mg/L dicamba each with 0.1mg/L BA was optimal fer embryogenic callus formation from mature seed and had a strong effect on successive plant regeneration. The regeneration frequency from embryogenic callus among cultivars were descending order of Roughrider > Frode > Frontier. Supplementation of the regeneration media with 10mg/L $AgNO_3$ and 40mg/L cysteine enhanced frequency of plant regeneration. Efficient regeneration system established in this study will be useful fur molecular breeding of orchardgrass through genetic transformation.

• Proceedings of the KGS Conference
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• 2002.05a
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• pp.99-105
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• 2002

변화의 속도가 느려서 장기지속적인 전체사의 바탕을 형성하고 있는 지리적 환경에 대한 적응결과로서의 지표경관을 도면상에 표현한 고지는 당시대인들의 세계관과 공간인식을 반영하고 있다. 인간을 둘러싼 지리적 환경은 장기적으로 벼하는 구조이다. 장기지속의 구조사는 지리지와 고지도에 잘 표현되어 있다. 지리지와 고지도에 대한 문헌조사와 현지야외답사를 통하여 경관을 구체적으로 분석하고 지역성과 한국전통지역사회의 원형을 파악하고자 한다. 기존의 연구자들에 의하여 정상기의 동국지도, 김정호의 대동여지도, 북방영토인식, 군현지도, 시대상의 복원과 지리환경 인식, 회화의 측면에서 본 고지도, 지명과 영토문제, 서양식 세계지도의 전래과정등의 연구주제들에 대하여 많은 연구가 이루어졌다. 그러나 기왕의 연구는 고지도에 대한 전체적인 현황 파악과 해제, 전체적인 유형 분류, 특정주제에 대한 고지도 이용 등에 초점이 맞추어져 있었고 구체적인 지역사회에 대하여 고지도를 통시대적으로 비교 분석한 연구는 드문 편이다. 사라져가고 있는 전통경관과 자연환경의 영향을 많이 받은 촌락경관이 남아 있는 지역사회경관에 대한 고지도와 지리지를 활용한 연구가 시급하다. 고지도는 옛 지명, 산천, 도로, 역원, 행정구역, 역사적 위치의 파악과 문화경과 복원의 기초자료로서의 의미가 크므로 지역사회 단위의 연구가 필요하다. 19세기 말엽에 편찬된 읍지와 지도는 서양과 일본의 침략으로 변모되기 이전의 한국 각 지역의 모습을 추적하고 복원하는데 긴요한 역사적 자료이다. 현대 한국지역사회의 바탕을 이루고 있는 지난 400년간의 지역변화를 고지도와 지리지.읍지를 통하여 살펴봄으로써 변한 것과 변하지 않는 것을 분석하여 시대상의 복원과 지역사회의 정체성 확립에 일조하고자 한다.곡물의 여러 줄기가 합수하고 물이 역류하지 않으며 잘 감아도는 곳으로 표현할 수 있다 이러한 명당의 기본적인 원리는 장풍(藏風)과 득수득파(得水得破)이다. 장풍과 득수란 '국'(局), 즉 산줄기와 수계로 이루어진 일정한 범위 속에 만물이 생태계 속에서 살아가는 모습인 '체형(體形)'의 의미가 나타나야 한다는 것이다. 그러나 이러한 의미는 시대에 따라 달라질 수 있는 것이다.면적의 52%를 점유하여 감자 재배지의 핵심지를 이룬다. 4. 한국 감자 재배지역 중심지의 지리적 특징은, 높은 산지지역의 산록완사면에 밭작물로 재배된다는 점과 교통이 불편한 지역으로서 도시화와 산업화 지역의 그늘 지역이 대부분이다. 강원도의 감자 재배지는 감자재배에 적합한 자연환경과 화전농업의 전통, 감자 재배기술의 전파, 중앙정부와 지방정부가 지원하는 각종 연구소 분포와 영농지도, 씨감자 생산과 협동조합의 판로 개척, 도로 개설과 포장 등의 인문지리적 요인이 영농조건을 개선하고 감자 판매를 위한 시장접근을 용이하게 하여, 남한 최대의 감자 재배지역을 형성하였다. 제주도는 산지지형과 따뜻한 기온으로 2기작이 가능하고, 감자가공 공장설립과 교통발달에 따른 육지 시장과의 접근이 용이해졌기 때문에 남한에서 2번째로 큰 감자재배지역이 되었다.(요약 및 결론에서 발췌)그람양성균에서 효과적이었으며, 농도별 항균력시험 결과 농도가 증가할수록 비례하여 저해율도 증가함을 알 수 있었다. 첨가농도를 달리하여 미생물의 생육도를 측정한 결과, fraction II磎꼭\ulcorner경우 그람양성균에 대해 500 ppm 이상에서 뚜렷한 증식억제효과를 나타내었다.서 뚜렷한 증식억제효과를 나타내었다.min/+}$계 수컷 이형접합체 형질전환 마우스에 AIN-76A 정제사료만을 투

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.1
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• pp.76-83
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• 1992

Enterotoxigenic E. coli is one of the major causative agents of the infantile diarrhea and traveler's diarrhea. The heat-stable enterotoxin (ST) is thought to be a virulence factor in the pathogenesis of the diarrhea and to be a maker for identification of the enterotoxigenic E. coli from non pathogenic E. coli. ST producing E. coli KM-7 strain was isolated from the swine and molecular cloning of ST gene of KM-7 strain. Transformant eKT-53 $(ST^+,\;LT^-)$ was selected by infant mouse assay (IMA). The culture supernatant of eKT-53 strain was performed purification by multipled steps. The culture supernatant (crude ST) was purified by sequentially applying batch adsorption chromatography on Amberlite XAD-2 resin, ion exchange chromatography on DEAE-Sephacel anion exchanger, gel filtration chromatography on Bio-Gel P-6 and preparative polyacrylamide slab gel electrophoresis. About 113-fold purification was achieved with a yield of about 11% of crude ST and the minimum effective dose(MED) of this purified ST was about 2.8ng in IMA. Homogeneity of purified ST was demonstrated by showing a single band in analytical SDS polyacrylamide disc gel electrophoresis.

• Korean Journal of Ichthyology
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• v.28 no.4
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• pp.215-222
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• 2016

Triploidy was induced in the marine medaka, Oryzias dancena by cold shock treatment ($0^{\circ}C$) of fertilized eggs for 30, 45, or 60 min, applied two minutes after fertilization. The triploid genotype was induced by each of the thermal shock regimes tested. The best result was obtained when the eggs were treated for 45 min, which induced triploidy in all the resulting fish. Triploidy was confirmed using chromosomal and flow cytometer analyses, and erythrocyte measurements. The surface areas and volumes of the erythrocytes of triploid fish were significantly larger than those of diploid fish, and their chromosome number (3N=72) was 1.5 times greater that for the diploids (2N=48). Based on a flow cytometer analysis, the triploid fish had approximately 1.5 times the cellular DNA content (2.40 pg/cell) of the diploid specimens (1.61 pg/cell). Data from this study provide the basis for the development of unique models for studying reproductive confinement in transgenic fish.

• KSBB Journal
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• v.10 no.5
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• pp.475-481
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• 1995

The effect of metallothionein expression on the metal resistance and removal by recombinant Saccharomyces cerevisiae containing the plasmid pJW9 was investigated. The recombinant strain S. cerevisiae BZ-pJ was constructed by transforming the host strain S. cerevisiae BZ3l-1-7Ba with the gene coding for a metal-binding protein, metallothionein. Introduction of the MT gene yielded an increase in the minimum inhibitory concentration (MIC) of copper more than three times compared with the host strain. The minimum inhibitory concentrations of $Cr^{2+}, Znr^{2+} and Pb^{2+}, $ were not different for the two strains. The recombinant yeast grown in a medium containing 8mM CuSO4 was able to remove copper with a capacity of 18.9mg $Cu^{2+}$/g dry cell. In a mixture of copper and zinc, the presence of copper relieved the toxic effects caused by zinc, resulting in an enhancement of the final cell density and the specific growth rate of the recombinant yeast. The capability to remove copper by the recombinant yeast was linearly proportional to the copper concentrations in the medium. The efficiency of copper removal was rather constant regardless of the initial copper concentrations. The specific removal of zinc was dependent on the zinc concentrations in media, though, and such dependence was not so pronounced as the concentration of copper.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.263-268
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• 2002

본 연구는 고추분쇄용 세라믹 롤 분쇄기를 이용하여 고춧가루 생산시, 분쇄효율을 향상시키고자 기존의 롤 분쇄속도 40rpm(0.352m/s)에서 80rpm(0.704%)으로 증가시키고, 기존의 롤 회전비 2:1에서 5:1로 증가시켜 고추분쇄시 전단력 증가로 분쇄능을 향상시켰고, 연구 내용의 주요 결과를 요약하면 다음과 같다. 1. 세라믹치형롤 분쇄속도 40rpm(0.352m/s)에서는 롤 회전비 2:1에서 1,190$\mu\textrm{m}$ 입자가 32.7%, 590$\mu\textrm{m}$ 입자가 19.7%였고, 롤 회전비를 5:1로 증가시 590$\mu\textrm{m}$ 입자가 30.9%, 420$\mu\textrm{m}$ 입자가 17.2%로 중간 미분쇄 영역의 분포가 증가하여 미분쇄 효율이 향상됨을 알 수 있었다. 2. 분쇄물의 롤 통과횟수에 따른 분쇄능은 세라믹치형롤 모두 분쇄속도 80rpm(0.704m/s)에서 분쇄물의 미분쇄능이 향상되었고, 분쇄생성물의 임계처리 횟수가 3~4차임을 분석할 수 있었다. 3. 보통 고춧가루를 생산하는데 분쇄속도 40rpm(0.352m/s), 80rpm(0.704m/s), 두 롤의 회전비 2:1, 3:1, 4:1하에서는 생산되지 않았으나, 롤 회전비 5:1에서는 분쇄속도 40rpm(0.352m/s)일 경우 7차 분쇄후에, 분쇄속도 80rpm(0.704m/s)일 경우 5차분쇄후에 생성되어 분쇄처리횟수가 2회정도 단축되어 전단력 증가로 인하여 분쇄능이 향상된 것으로 분석되었다. 4. 기존의 고춧가루 분쇄조건인 분쇄속도 40rpm(0.352m/s), 롤 회전비 2:1보다 본 연구에서 개발한 분쇄속도 80rpm(0.704m/s), 롤 회전비 5:1인 분쇄조건이, 분쇄처리 횟수 단축 등이 분석됨으로서 섬유질이 많이 포함된 고춧가루 등의 재료가공 분쇄기술이 향상된 것으로 분석되었다.. 마늘재배 일관기계화에 의한 노동투하시간과 비용 -종자준비부터 통마늘선별까지의 일관기계화로 투입된 주요작업의 노력은 75∼76%가 절감되고, 재배규모 3ha기준시 비용은 44-53%절감되었음. the annealing texture. Observations by TEM and EBSD revealed the formation of very fine grains of ∼1.0$\mu\textrm{m}$ after CCSS.he dislocations form local defect arrangements at the grooves permitting the substantial reduction in defect density over the remainder of the interfacial area.한 최대의 감자 재배지역을 형성하였다. 제주도는 산지지형과 따뜻한 기온으로 2기작이 가능하고, 감자가공 공장설립과 교통발달에 따른 육지 시장과의 접근이 용이해졌기 때문에 남한에서 2번째로 큰 감자재배지역이 되었다.(요약 및 결론에서 발췌)그람양성균에서 효과적이었으며, 농도별 항균력시험 결과 농도가 증가할수록 비례하여 저해율도 증가함을 알 수 있었다. 첨가농도를 달리하여 미생물의 생육도를 측정한 결과, fraction II磎꼭\ulcorner경우 그람양성균에 대해 500 ppm 이상에서 뚜렷한 증식억제효과를 나타내었다.서 뚜렷한 증식억제효과를 나타내었다.min/+}$계 수컷 이형접합체 형질전환 마우스에 AIN-76A 정제사료만을 투여한 대조군은 1.40$\pm$0.24(100%)에 비하여 I3C 저농도 투여 실험군(Group 1; 0.85$\pm$0.23; 61%, P<0.01), 그리고 I3C 고농도 투여 실험군(Group 2 ; 1.32$\pm$0.29 ; 94%)의 순으로 감소하였다. 선종의 크기별 종양의 발생개수의

• Reproductive and Developmental Biology
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• v.30 no.3
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• pp.181-187
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• 2006

In recent years the number of patients waiting for organ transplantation has greatly outpaced the supply of human organs available, which leads to a renewed interest in pig-to-human xenotransplantation as an alternative. However, one of the biggest barriers in the xenotransplantation is presence of porcine endogenous retroviruses(PERV) that can infect human cells. In this study, to present a possible solution for this problem we tried to inhibit expression of PERVs using shRNAs(short hairpin RNA) at the level of RNA synthesis and virus release. The shRNA targeting the sequence of PERV A, B type was cloned into pSIREN-RetroQ vector under the control of polymerase-III U6-RNA gene promoter. Quantitative real-time PCR was performed to detect my alterations in mRNA production of PERV A, B targeted by the shRNA in each done. Depending on the target sequence of the shRNA, the transcription of PERV was decreased to as much as 4% and the number of progeny viruses was reduced to less than 1/200,000. Transgenic pigs producing such shRNAs may result in a highly reduced PERV expression in cells and organs, which is a prerequisite for safe xenotransplantations.

• Reproductive and Developmental Biology
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• v.30 no.3
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• pp.157-162
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• 2006

Endogenous 84 amino acid parathyroid hormone(PTH) is synthesized as a pre-pro hormone by the chief cells of the parathyroid glands. Physiological actions of PTH include regulation of bone metabolism, renal tubular reabsorption of calcium and phosphate, and intestinal calcium absorption. In addition, PTH stimulates new bone formation by extraordinary stimulation of osteoblastic activity and decreasing calcium excretion by the kidney. In this study, we constructed and tested retrovirus vectors designed to express the human parathyroid hormone(hPTH) gene under the control of the tetracycline-inducible promoters. To increase the hPTH gene expression at turn-on state, woodchuck hepatitis virus posttranscriptional regulatory element(WPRE) sequence was also introduced into retrovirus vector at downstream region of either the hPTH gene or the sequence encoding reverse tetracycline-controlled transactivator(rtTA). Transformed primary culture cells(porcine fetal fibroblast, PFF, chicken embryonic fibroblast, CEF) were cultured in the medium supplemented with or without doxycycline(tetracycline derivative) for 48 hours, and induction efficiency was measured by comparing the hPTH gene expression level using two step RT-PCR and ELISA Higher hPTH expression($3{\tims}10^4\;pg/ml,\;5.3{\times}10^4\;pg/ml$) and tighter expression control(up to 8 fold) were observed from the vector in which the WPRE sequence was placed at downstream of the hPTH gene. The resulting tetracycline inducible vector system may be helpful in solving serious physiological disturbance problems which have been a major obstacle in successful production of transgenic animals.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.4
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• pp.401-411
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• 2015

This study was performed to investigate the wound healing effect of skin regeneration cosmetics utilizing low molecular weight Polydeoxynucleotide (PDRN). High purity PDRN was prepared from salmon testes poly-deoxy-ribonucleotide through protein and toxin removal process and molecular weight reduction. In order to evaluate the wound healing effect of PDRN in SD rats, 4 sites of dorsal skin of each animal were excised by using biopsy punch and $500{\mu}L$ of test solution was topically applied once daily for 4 weeks. The tissue changes were observed for every week during the application periods. After applying the PDRN to the wound, the skin was cut flower and contraction of the wounds more quickly, and the coating of PDRN in the wound area was reduced significantly as compared to the positive control group $Fucidin^{(R)}$ applied. The microscopic observation of stained tissue showed that a positive control was most rapid in re-epithelialization ability followed by the PH group, PDRN group, HA group. In addition, transforming growth factor ($TGF-{\beta}$) and vascular endothelial growth factor (VEGF), such as in the growth factor was similar to the results of staining of tissue lesions. In conclusion, it is determined that the low molecular weight PDRN has the therapeutic effect to the wound, and could be used as a functional material of cosmetics and medical industries.