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      • 灌漑用水路의 水路損失率 算定에 관한 硏究

        李基春,具滋雄,金在英,李宰泳,徐元明 전북대학교 농업과학기술연구소 1982 農大論文集 Vol.13 No.-

        This study was carried out in order to estimate water losses in irrigation canals, which may be used to evaluate the water requirement for irrigation projects. The conveyance losses were measured by the inflow-outflow method, the seepage were measured by the ponding method, and the operation losses in the course of irrigation were calculated by comparing the two kinds of losses. The results obtained in this experiment were as follows : Conveyance losses per unit area of wetted perimeter per second by the main irrigation canal, the secondary irrigation canal and the tributary irrigation, canal, were 1.399x10-5m3/m3/sec, 5.154x10-5m3/m3/sec, and 2.670×10-5m3/m3/sec respectively in the Goong-sa area. And they were 1.934x10-5m3/m3/sec, 2.149x10-5m3/m3/sec, and 4.558x10-6m3/m3/sec respectively in the Seong-dug area. Seepage losses per unit area of wetted perimeter per second by the secondary irrigation canal and the tributary irrigation canal, were 2.180×10-6m3/m3/sec and 2.168×10-6m3/m3/sec in the Goons-sa area. 1.150x10-6m3/m3/sec and 1.084x10-6m3 /m3/sec in the Seong-dug area respectively. Operation losses per unit area of wetted perimeter per second by the secondary irrigation canal and the tributary irrigation canal, were 4.936×10-5m3/m3/sec and 2.453×10-5m3/m3/sec in the Goong-sa area, 2.034×10-5m3/m3/sec and 4.450×10-5m3/m3 /sec in the Seong-dug area respectively. Conveyance, seepage and operation losses in the Goong-sa area were 6.7%, 94.6%, and 14.0% more than those in the Seong-dug area. Operation losses amount to about 17 times as much as seepage losses in the Goons-sa area and about 29 times in the Seong-dug area .The seepage losses depend much on the soil texture. ranging from 7.437×10-7m3/m3/sec to 2.430x10-6 m3/m3/sec. Water loss rates in the main irrigation canal, the secondary irrigation canal and the tributary irrigation canal, were estimated as 8.49%. 37.27%, and 9.8l%, respectively in the Goong-sa area. And they were estimated as 15.10%, 32.67% and 13.73% respectively in the Seong-dug area.

      • 1RA-7 : K<sub>2</sub>WO<sub>4</sub> flux 에 의한 K<sub>2</sub>Oㆍ6TiO<sub>2</sub> whisker 의 합성

        이진식 ( J. S. Lee ),이상문 ( S. M. Lee ),이철태 ( C. T. Lee ),권긍택 ( K. T. Kohn ),김영명 ( Y. M. Kim ) 한국공업화학회 1993 한국공업화학회 연구논문 초록집 Vol.1993 No.0

        K<sub>2</sub>Oㆍ6TiO<sub>2</sub> whisker는 구조적인 특성 때문에 물리ㆍ화학적으로 매우 안정하며 보강재, 마찰재, 단열재 등의 많은 용도를 갖게된다. 특히 최근에는 석면이 발암물질로 인한 자동차 브레이크 마찰재료의 사용이 금지됨에 따라 K<sub>2</sub>Oㆍ6TiO<sub>2</sub> whisker는 이의 대체 섬유로서 주목을 받고 있다. 이러한 K<sub>2</sub>Oㆍ6TiO<sub>2</sub> whisker의 합성방법으로는 TiO<sub>2</sub>와 K<sub>2</sub>CO<sub>3</sub>의 화학양론적 조성의 혼합들을 설정온도에서 소성(calcination method)시키는 방법을 비롯하여 응용법(melting method), 수열법(hydrothermal method), 융제법(flux) 및 KDC법(kneading-drying-calcination method) 등의 방법이 있다. 그러나 수열법의 경우 양질의 whisker를 얻을 수 있으나 고압합성 이므로 위험하고 가격이 비싼 결점이 있으며 공업상 제조에 필요한 조건이 복잡하고 연속조작이 어려워 비현실적인 방법이다. 또한 서냉소성법의 경우 공정이 단순하며 공업화가 쉬우나 비교적 장섬유가 얻어지게 된다. 따라서 본 연구에서는 융제법을 이용하여 K<sub>2</sub>Oㆍ6TiO<sub>2</sub> whisker를 합성하였으며. 과거에 용제로 사용된 KC1-KF계. K<sub>2</sub>O-Na<sub>2</sub>O-B<sub>2</sub>O<sub>3</sub>계 등의 높은 volatility와 viscosity 그리고 낮은 solubility에 대한 문제점을 개선하기 위해 K<sub>2</sub>WO<sub>4</sub>를 flux로 선정하여 K<sub>2</sub>Oㆍ6TiO<sub>2</sub> whisker를 합성하였다.

      • 2단계 급속동결 및 초자화 동결한 토끼상실배의 체외생존성에 관한 연구

        정구민,이창규,임경순,김수헌 서울대학교농과대학농업개발연구소 1990 서울대농학연구지 Vol.15 No.1

        본 시험은 수정란 급속동결보존기술의 개발을 위한 기초자료를 얻기 위하여 2단계 급속동결 및 초자화동결이 토끼 상실배의 체외발생등에 미치는 영향을 검토하고자 실시하였으며, 얻어진 결과는 다음과 같다. 1. 토끼 상실배를 1.5, 2.0, 2.5 및 3.0 M glycerol과 0.5 M sucrose가 포함된 동결액에 실온에서 10분간 노출후 -30℃에서 30∼40분간 정치하여 급속동결하였을 때 발생율은 각각 36.4, 83.3, 92.3 및 84.2%로 2.5 M glycerol에서 가장 높았다. 2. 토끼 상실배를 1.5, 2.0, 2.5 및 3.0 M 1,2-propanediol과 0.5 M sucrose가 포함된 동결액에 실온에서 10분간 노출 후 -30℃에서 30∼40분간 정치하여 급속동결하였을 때 발생율은 각각 26.6, 55.6, 65.0 및 52.9%로 2.5 M 1,2-propanediol에서 가장 높았으나, glycerol을 사용했을 때 보다 낮았다. 3. 토끼 상실배를 2.5, 3.0 및 3.5 M glycerol과 0.5 M trehalose가 포함된 동결액에 실온에서 10분간 노출후 액체질소에 침지하여 초급속동결한 결과 회수율은 각각 87.5, 92.5 및 92.5%, 형태적으로 정상인 수정란의 비율은 각각 37.5, 55.5 및 60.0%, 그리고 발생율은 각각 13.3, 36.4 및 37.5%로 3.5 M glycerol에서 가장 높았으나 초자화동결법보다 현저하게 낮았다. 4. 토끼 상실배를 25% glycerol과 25% 1,2-propanediol을 함유한 동결액에 실온에서 10분간 노출후 초자화동결했을 때 발생율은 75.0%로 실온에서 형평한 후 초자화동결이 가능하였다. This experiment was carried out to investigate on in vitro development of rabbit monla frozen by 2-step feezing and vitrification. The results obtained from this experiment are as follows; 1. When rabbit morula in m-PBS containing 1.5, 2.0, 2.5 or 3.0 M glyceral and 0.5 M sucrose for 10 min at room temperature were cooled at -30℃ for 30 to 40 min and plunged into liquid nitrogen, the proportion of embryo developed to expanded blastoyst was 36.4, 83.3, 92.3 and 84.2%, respectively. Glycerol 2.5 M showed higher survival than others. 2. When rabbit morula in m-PBS containing 1.5, 2.0, 2.5 or 3.0 M 1, 2-propanediol and 0.5 M sucrose for 10 min at room temperature were cooled at -30℃ for 30 to 40 min and plunged into liquid nitrogen, the proportion of embrye developed to expanded blastocyst was 26.6, 55.6, 65.0 and 52.9%, respectively. 1, 2-propanediol was less effective than glycerol. 3. When rabbit morula in m-PBS containing 2.5, 3.0 or 3.5 M glycerol and 0.5 M trehalose for 10 min at room temperature were plunged into liquid nitrogen and thawed rapidly, the recovery rate of embryo was 87.5, 92.5 and 92.5%, the proportion of morphologically normal embryo was 37.5, 55.5 and 60.0%, and the proportion of embryo developed to expanded blastocyst was 13.3. 36.4 and 37.5%, respectively. The proportion of embryo developed to expanded blastocyst was higher in vitrification than in plunging into liquid nitrogen. 4. When rabbit morula were frozen by vitrification in m-PBS containing 25% glycerol. 25% 1, 2-propanediol, the proportion of embryo developed to expanded blastocyst was 75.0%, the result suggested that rabbit embryos could be frozen by vitrification after equilibration at room temperature.

      • SCISCIESCOPUS

        Supplemented vaccination with tandem repeat M2e virus-like particles enhances protection against homologous and heterologous HPAI H5 viruses in chickens

        Song, B.M.,Kang, H.M.,Lee, E.K.,Jung, S.C.,Kim, M.C.,Lee, Y.N.,Kang, S.M.,Lee, Y.J. Butterworths ; Elsevier Science Ltd 2016 Vaccine Vol.34 No.5

        Highly pathogenic avian influenza (HPAI) H5 viruses derived from A/Goose/Guangdong/1/96 have been continuously circulating globally, severely affecting the public health and poultry industries. The matrix 2 protein ectodomain (M2e) is considered a promising candidate for a universal cross-protective influenza vaccine that provides more effective control over HPAI H5 viruses harboring variant hemagglutinin (HA)-antigens. Here, we evaluated the protective efficacy of a tandem repeat construct of heterologous M2e presented on virus-like particles (M2e5x VLPs) either alone or as a supplement against HPAI H5 viruses in a chicken model. Chickens immunized with M2e5x VLPs alone induced M2e-specific antibodies but were not protected against HPAI H5. The homo- and cross-protective efficacy of M2e5x VLP-supplemented vaccination of chickens was also examined. Importantly, supplementation with M2e5x VLPs induced significantly higher levels of antibodies specific for M2e and different viruses as well as provided improved protection against homologous and heterologous HPAI H5 viruses. Considering the limited efficacy of inactivated vaccines, supplement vaccination with M2e5x VLPs may be an effective measure for preventing outbreaks of HPAI viruses that have the ability to constantly change their antigenic properties in poultry.

      • Metabolic characterization of (1-(5-fluoropentyl)-1H-indol-3-yl)(4-methyl-1-naphthalenyl)-methanone (MAM-2201) using human liver microsomes and cDNA-overexpressed cytochrome P450 enzymes

        Kong, T. Y.,Kim, J. H.,Choi, W. G.,Lee, J. Y.,Kim, H. S.,Kim, J. Y.,In, M. K.,Lee, H. S. Springer Science + Business Media 2017 Analytical and bioanalytical chemistry Vol.409 No.6

        <P>MAM-2201 is a synthetic cannabinoid that is increasingly found in recreational drug abusers and cases of severe intoxication. Thus, characterization of the metabolic pathways of MAM-2201 is necessary to predict individual pharmacokinetics and toxicity differences, and to avoid toxic drug-drug interactions. Collectively, 19 phase 1 metabolites of MAM-2201 were identified using liquid chromatography-Orbitrap mass spectrometry following human liver microsomal incubations in the presence of NADPH: 7 hydroxy-MAM-2201 (M1-M7), 4 dihydroxy-MAM-2201 (M8-M11), dihydrodiol-MAM-2201 (M12), N-(5-hydroxypentyl)-MAM-2201 (M13), hydroxy-M13 (M14), N-dealkyl-MAM-2201 (M15), 2 hydroxy-M15 (M16, M17), MAM-2201 N-pentanoic acid (M18), and hydroxy-M18 (M19). On the basis of intrinsic clearance values in human liver microsomes, hydroxy-MAM-2201 (M1), N-(5-hydroxypentyl)-MAM-2201 (M13), and hydroxy-M13 (M14) were the major metabolites. Based on an enzyme kinetics study using human cDNA-expressed cytochrome P450 (CYP) enzymes and an immunoinhibition study using selective CYP antibodies in human liver microsomes, CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 enzymes were responsible for MAM-2201 metabolism. The CYP3A4 enzyme played a prominent role in MAM-2201 metabolism, and CYP1A2, CYP2B6, CYP2C8, and CYP2C9 enzymes played major roles in the formation of some metabolites. MAM-2201 is extensively metabolized by multiple CYP enzymes, indicating that MAM-2201 and its metabolites should be used as markers of MAM-2201 abuse and toxicity.</P>

      • Anti-glycation and anti-angiogenic activities of 5'-methoxybiphenyl-3,4,3'-triol, a novel phytochemical component of Osteomeles schwerinae

        Lee, Y.M.,Kim, J.,Kim, C.S.,Jo, K.,Yoo, N.H.,Sohn, E.,Kim, J.S. North-Holland ; Elsevier Science Ltd 2015 european journal of pharmacology Vol.760 No.-

        Advanced glycation end products (AGEs) are involved in the development of diabetic complications such as diabetic retinopathy. 5'-methoxybiphenyl-3,4,3'-triol (referred to as K24) was isolated using bioactivity-guided fractionation of Osteomeles schwerinae C. K. Schneid. and identified as a potent AGE inhibitor. To identify the protective effect of K24 on disruption of the blood-retinal barrier, AGE-RSA was intravitreally injected into rat eyes. K24 had an inhibitory effect on AGE-RSA-induced retinal vascular leakage by suppressing the expression of vascular endothelial growth factor (VEGF) and decreasing the loss of occludin. In addition, we examined whether K24 has a preventive effect against retinal pathogenic angiogenesis in an oxygen-induced retinopathy (OIR) mouse model. K24 significantly reduced the retinal non-perfused area and neovascular tufts in the OIR mice. These data indicate that K24 could serve as an innovative pharmaceutical agent to prevent blood-retinal barrier breakage and retinal pathogenic angiogenesis through an anti-VEGF mechanism.

      • Moracin M inhibits airway inflammation by interrupting the JNK/c-Jun and NF-κB pathways in vitro and in vivo

        Lee, J.H.,Ko, H.J.,Woo, E.R.,Lee, S.K.,Moon, B.S.,Lee, C.W.,Mandava, S.,Samala, M.,Lee, J.,Kim, H.P. North-Holland ; Elsevier Science Ltd 2016 european journal of pharmacology Vol.783 No.-

        <P>The therapeutic effectiveness of moracins as 2-arylbenzofuran derivatives against airway inflammation was examined. Moracin M, O, and R were isolated from the root barks of Morus alba, and they inhibited interleukin (IL)-6 production from IL-1 beta-treated lung epithelial cells (A549) at 101-00 mu M. Among them, moracin M showed the strongest inhibitory effect (IC50=8.1 mu M). Downregulation of IL-6 expression by moracin M was mediated by interrupting the c-Jun N-terminal kinase (JNK)/c-Jun pathway. Moracin derivatives inhibited inducible nitric oxide synthase (iNOS)-catalyzed NO production from lipopolysaccharide (LPS)-treated alveolar macrophages (MH-S) at 50-100 mu M. In particular, moracin M inhibited NO production by downregulating iNOS. When orally administered, moracin M (20-60mg/kg) showed comparable inhibitory action with dexamethasone (30mg/kg) against LPS-induced lung inflammation, acute lung injury, in mice with that of dexamethasone (30mg/kg). The action mechanism included interfering with the activation of nuclear transcription factor-kB in inflamed lungs. Therefore, it is concluded that moracin M inhibited airway inflammation in vitro and in vivo, and it has therapeutic potential for treating lung inflammatory disorders. (C) 2016 Elsevier B.V. All rights reserved.</P>

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        A novel chimeric promoter that is highly responsive to hypoxia and metals

        Lee, J-Y,Lee, Y-S,Kim, J-M,Kim, K L,Lee, J-S,Jang, H-S,Shin, I-S,Suh, W,Jeon, E-S,Byun, J,Kim, D-K Nature Publishing Group 2006 Gene Therapy Vol.13 No.10

        To develop a potent hypoxia-inducible promoter, we evaluated the usefulness of chimeric combinations of the (Egr-1)-binding site (EBS) from the Egr-1 gene, the metal-response element (MRE) from the metallothionein gene, and the hypoxia-response element (HRE) from the phosphoglycerate kinase 1 gene. In transient transfection assays, combining three copies of HRE (3 × HRE) with either EBS or MRE significantly increased hypoxia responsiveness. When a three-enhancer combination was tested, the EBS–MRE-3 × HRE (E–M–H) gave a hypoxia induction ratio of 69. The expression induced from E–M–H-pGL3 was 2.4-fold higher than that induced from H-pGL3 and even surpassed the expression from a human cytomegalovirus promoter-driven vector. The high inducibility of E–M–H was confirmed by validation studies in different cells and by expressing other cDNAs. Gel shift assays together with functional overexpression studies suggested that increased levels of hypoxia-inducible factor 1α, metal transcription factor-1 and Egr-1 may be associated with the high inducibility of the E–M–H chimeric promoter. E–M–H was also induced by hypoxia mimetics such as Co<SUP>2+</SUP> and deferoxamine (DFX) and by hydrogen peroxide. Gene expression from the E–M–H was reversible as shown by the reduced expression of the transgene upon removal of inducers such as hypoxia and DFX. In vivo evaluation of the E–M–H in ischemic muscle revealed that erythropoietin secretion and luciferase and LacZ expression were significantly higher in the E–M–H group than in a control or H group. With its high induction capacity and versatile means of modulation, this novel chimeric promoter should find wide application in the treatment of ischemic diseases and cancer.Gene Therapy (2006) 13, 857–868. doi:10.1038/sj.gt.3302728; published online 9 February 2006

      • Effects of Changes in Glycosylation Sites on Secretion of Recombinant Human Erythropoietin in Cultured CHO Cells

        Lee,H. G,P. Y. Lee,Y. K. Lee,S. J. Kim,H. K. Chung,M. K. Seo,J. K. Park,K. S. Min,W. K. Chang 한국동물번식학회 2003 Reproductive & developmental biology Vol.27 No.4

        The effects of additions/deletions in glycosylated residues of recombinant human EPO (rhEPO) produced in CHO-K1 on their secretion were examined. hEPO cDNA was amplified from human liver mRNA and cloned into the pCR2.1 TOPO. Using overlapping-extension site-directed mutagenesis method, glycosylation sites at 24th, 38th, 83rd, and 126th were respectively or accumulatively removed by substituting its asparagine (or serine) with glutamine. To add novel glycosylation sites, 69 and 105th leucine was mutated to asparagine. Mutant and wild type rhEPO constructs were cloned into the pcDNA3 expression vector with CMV promoter and transfected into CHO cell line, CHO-K1, to produce mutant rhEPO mutant rhEPO proteins. Enzyme-linked immunosorbant assay (ELISA) and Western analysis with monoclonal anti-EPO antibody were performed using supernatants of the cultures showing transient and stable expressions respectively. Addition of novel glycosylation reduced rhEPO secretion dramatically while deletion mutants had little effect except some double deletion mutants (△24/83 and △38/83) and triple mutant (△24/38/83). This fact suggests that not single but combination of changes in glycosyl groups affect secretion of rhEPO in cell culture, possibly via changes in their conformations.

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