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Calculation of Low-Energy Reactor Neutrino Spectra for Reactor Neutrino Experiments

  • Riyana, Eka Sapta;Suda, Shoya;Ishibashi, Kenji;Matsuura, Hideaki;Katakura, Jun-ichi
    • Journal of Radiation Protection and Research
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    • v.41 no.2
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    • pp.155-159
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    • 2016
  • Background: Nuclear reactors produce a great number of antielectron neutrinos mainly from beta-decay chains of fission products. Such neutrinos have energies mostly in MeV range. We are interested in neutrinos in a region of keV, since they may take part in special weak interactions. We calculate reactor antineutrino spectra especially in the low energy region. In this work we present neutrino spectrum from a typical pressurized water reactor (PWR) reactor core. Materials and Methods: To calculate neutrino spectra, we need information about all generated nuclides that emit neutrinos. They are mainly fission fragments, reaction products and trans-uranium nuclides that undergo negative beta decay. Information in relation to trans-uranium nuclide compositions and its evolution in time (burn-up process) were provided by a reactor code MVP-BURN. We used typical PWR parameter input for MVP-BURN code and assumed the reactor to be operated continuously for 1 year (12 months) in a steady thermal power (3.4 GWth). The PWR has three fuel compositions of 2.0, 3.5 and 4.1 wt% $^{235}U$ contents. For preliminary calculation we adopted a standard burn-up chain model provided by MVP-BURN. The chain model treated 21 heavy nuclides and 50 fission products. The MVB-BURN code utilized JENDL 3.3 as nuclear data library. Results and Discussion: We confirm that the antielectron neutrino flux in the low energy region increases with burn-up of nuclear fuel. The antielectron-neutrino spectrum in low energy region is influenced by beta emitter nuclides with low Q value in beta decay (e.g. $^{241}Pu$) which is influenced by burp-up level: Low energy antielectron-neutrino spectra or emission rates increase when beta emitters with low Q value in beta decay accumulate Conclusion: Our result shows the flux of low energy reactor neutrinos increases with burn-up of nuclear fuel.

Cloning and Molecular Characterization of Epoxide Hydrolase from Aspergillus niger LK (Apergillus niger LK 유래의 Epoxide Hydrolase 클로닝 및 특성 분석)

  • 이은열;김희숙
    • KSBB Journal
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    • v.16 no.6
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    • pp.562-567
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    • 2001
  • Aspergillus niger LK harboring the enantioselective epoxide hydrolase (EHase) activity was isolated, and enantioselectivity of EHase was tested for various racemic aromatic epoxides. The gene encoding epoxide hydrolase was cloned from cDNA library generated by reverse transcriptase-polymerase chain reaction of the isolated total mRNA. Sequence analysis showed that the cloned gene encodes 398 amino acids with a deduced molecular mass of 44.5 kDa. Database comparison of the amino acid sequence reveals that it is similar to fungal EHase, whereas the sequence identity with bacterial EHase is very low. Recombinant expression of the cloned EHase in Escherichia coli BL21 yielded an active EHases, which can offer a potential biocatalyst for the production of chiral epoxides.

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The Effectiveness of Non-pharmacologic Interventions for Chronic Nonspecific Low Back Pain: A Systematic Review and Meta-analysis (국내 비특이적 만성 요통 환자에게 적용한 비약물적 중재의 효과: 체계적 문헌고찰 및 메타분석)

  • Jung, Mijung;Lee, Haein
    • Journal of East-West Nursing Research
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    • v.26 no.1
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    • pp.1-16
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    • 2020
  • Purpose: The purpose of this study was to evaluate the effectiveness of non-pharmacologic interventions for chronic nonspecific low back pain (CLBP) in adults aged 18-64 years. Methods: We searched for potentially relevant randomized controlled trials and non-randomized controlled trials through five Korean electronic databases (i.e., Korean Studies Information Service System, Research Information Sharing Service, Korean Medical Database, KoreaMed, and National Assembly Library) published from January 2010 to May 2019. Two investigators independently selected the studies based on the criteria and assessed risk of bias in the included studies. We estimated the effect size of interventions using Comprehensive Meta Analysis 3.3. Results: Of 10,151 studies, 26 studies met the inclusion criteria and 15 studies were included in the meta-analysis. Exercise reduced low back pain (Hedges's g=-1.53, 95% CI: -2.22 to -0.85) and pain-related disabilities (Hedges's g=-0.92, 95% CI: -1.40 to -0.45). We found that taping was effective in decreasing low back pain (Hedges's g=-1.12, 95% CI: -1.51 to -0.73) and pain-related disabilities (Hedges's g=-0.50, 95% CI: -0.93 to -0.07). Manual therapy yielded a marginally significant reduction in low back pain (Hedges's g=-2.32, 95% CI: -4.64 to 0.00), the therapy was not effective in decreasing pain-related disabilities. Conclusion: Although there was little evidence for the effectiveness of manual therapy in adults with CLBP, exercise and taping were effective to relieve pain and pain-related disabilities. Based on these findings, we suggest the development of non-pharmacologic interventions or a nursing intervention protocol for the CLBP management. Also, nurses should consider implementation of effective non-pharmacologic interventions for CLBP.

Analysis of Recent Clinical Studies to Establish Korean Herbal Medicine Clinical Trial Guidelines for the Common Cold (감기 임상시험 가이드라인 제정을 위한 최신 임상시험 연구 분석)

  • Kim, Kwan-il;Lee, Ho-jung;Lee, Beom-joon;Jung, Hee-jae;Jung, Sung-ki;Lee, Jun-hee
    • The Journal of Internal Korean Medicine
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    • v.37 no.1
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    • pp.109-134
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    • 2016
  • Objectives: The aim of this study was to help develop a guideline for the common cold. We searched recent clinical studies of the common cold in Western medicine and reviewed their objectives, inclusion and exclusion criteria, primary outcome, secondary outcome, and assessment tools to establish evidenced-based guideline.Methods: We searched electronic databases (Cochrane Library, MEDLINE, EMBASE) to identify eligible randomized controlled trials (RCTs) about the common cold for the last 10 years. We included 29 RCTs and showed their research summary via their objectives, participants, interventions, control, treatment duration, and results. We also analyzed the definition of the common cold presented in the article, inclusion and exclusion criteria, primary and secondary outcomes, and assessment tools.Results: We reported the aforementioned areas in detail. At first, the definition of the common cold was confused across the articles. Second, herbal medication clinical trials for the common cold have been extensively studied recently. Third, the eligibility criteria frequently included the Jackson Symptom score. Fourth, validated assessment tools (i.e., the Wisconsin Upper Respiratory Symptom Survey-21) have only been used in a few recent studies.Conclusions: Our research will be helpful to establish Korean herbal medicine clinical trial guidelines for the common cold.

Alternative Sigma Factor HrpL of Pectobacterium carotovorum 35 is Important for the Development of Soft-rot Symptoms

  • Nam, Hyo-Song;Park, Ju-Yeon;Kang, Beom-Ryong;Lee, Sung-Hee;Cha, Jae-Soon;Kim, Young-Cheol
    • Research in Plant Disease
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    • v.17 no.2
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    • pp.111-120
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    • 2011
  • A bacterial artificial chromosome library of Pectobacterium carotovorum 35 was constructed to characterize the genome and to sequence its hrp region. The hrp cluster of P. carotovorum 35 consisted of 26 open reading frames in five operons. A promoter-based green fluorescent protein technology was used to identify the genes regulated by the alternative sigma factor, HrpL, in P. carotovorum 35. The majority of the selected clones contained the hrpJ operon promoter sequence, which harbors a hrp box, but no putative hrp boxes were detected within the promoter sequences of two other hrpL-regulated genes encoding for pectate lyase and large repetitive protein. Although the promoters of five other hrp operons also contained hrp boxes, their expression was not HrpL-dependent in the promoter-based selection in E. coli. However, transcriptional analysis showed that expression from all operons harboring hrp boxes, except for the hrpN operon, was reduced significantly in the hrpL mutant. The severity of soft-rot symptoms when the hrpL mutant was applied to the surface of tobacco leaves, mimicking natural infection, was greatly attenuated. These results indicate that the hrpL gene of P. carotovorum 35 may be involved in the development of soft-rot symptoms.

Cloning of Elicitor-Inducible 5-epi-Aristolochene Hydroxylase in Tobacco Cell Suspension Culture (담배 현탁배양 세포의 Elicitor 유도성 5-epi-Aristolochene Hydroxylase 유전자의 클로닝)

  • Soon Tae Kwon;In-Jung Lee;Joseph Chappell
    • Journal of Life Science
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    • v.8 no.5
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    • pp.604-613
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    • 1998
  • The last enzyme of the sesquiterpen phytoalexin capsidiol synthesis in tobacco cell, 5-epi-aristolochene hydro-xylase which convert 5-epi-aristolochene (EAS) to capsidiol, was cloned by a reverse transcription polymerase chain reaction strategy and cDNA library screening. Cloned CYP-B3 contained high probability amino acid matches to known plant cytochrome P450 sequences and open reading frame with the conserved FxxGxRxCxG heme-binding region. Transcripts of CYP-B3 were not detected in control cells, but induced in elicitor-treated cells. Furthermore, CYP-B3 transcripts were induced by fungal extracts and cellulase but not by other stimuli(chilling, heat shock and 2,4-D). Induction of CYP-B3 transcripts by elicitor treatment was not affected by ancymidol and ketoconazole treat-ments suggesting that an inhibition of hydroxylase activity by Cyt P450 inhibitors resulting from post translational processing event.

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Molecular Approaches to Determine the Character of Serratia marcescens Associated with the Insect Pathogenicity to Brown Planthopper (Serratia marcescens의 곤충 병원성 관련형질 탐색을 위한 분자생물학적 연구)

  • 김희규;배동원;박진희;윤한대
    • Korean journal of applied entomology
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    • v.32 no.3
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    • pp.330-337
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    • 1993
  • A bacterium, pathogenic to Nilaparvata lugens Stal. causing high mortality in 3~5 days, were selected and identified as Serratuz marcescens biotype A2a which is not a nosocomlally infective strain. In order to determine the characters of Serratia marcesce'1lS associated with insect pathogenicity, Tn5 mutagenesis was carried out by conjugating with E. coli pJB4J1. Transconjugants were plate-assayed for missing chitinase, protease and DNase activity. A protease negative mutant was selected for missing JOseet pathogenicity. SEM and TEM revealed the presence of bacterial cells in the epithelial tissue of inner abdomal tissue of the hypodermic layer of abdomen. Such a colonization was limmited to the subjacent tissue inside the intacL cuticular epidermis. These observation supported our result of pathogenicity tests of transconjugants.

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Evaluation of Luminescent P450 Analysis for Directed Evolution of Human CYP4A11

  • Choi, Seunghye;Han, Songhee;Lee, Hwayoun;Chun, Young-Jin;Kim, Donghak
    • Biomolecules & Therapeutics
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    • v.21 no.6
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    • pp.487-492
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    • 2013
  • Cytochrome P450 4A11 (CYP4A11) is a fatty acid hydroxylase enzyme expressed in human liver. It catalyzes not only the hydroxylation of saturated and unsaturated fatty acids, but the conversion of arachidonic acid to 20-hydroxyeicosatetraenoic acid (20-HETE), a regulator of blood pressure. In this study, we performed a directed evolution analysis of CYP4A11 using the luminogenic assay system. A random mutant library of CYP4A11, in which mutations were made throughout the entire coding region, was screened with luciferase activity to detect the demethylation of luciferin-4A (2-[6-methoxyquinolin-2-yl]-4,5-dihydrothiazole-4-carboxylic acid) of CYP4A11 mutants in Escherichia coli. Consecutive rounds of random mutagenesis and screening yielded three improved CYP4A11 mutants, CP2600 (A24T/T263A), CP2601 (T263A), and CP2616 (A24T/T263A/V430E) with ~3-fold increase in whole cells and >10-fold increase in purified proteins on the luminescence assay. However, the steady state kinetic analysis for lauric acid hydroxylation showed the significant reductions in enzymatic activities in all three mutants. A mutant, CP2600, showed a 51% decrease in catalytic efficiency ($k_{cat}/K_m$) for lauric acid hydroxylation mainly due to an increase in $K_m$. CP2601 and CP2616 showed much greater reductions (>75%) in the catalytic efficiency due to both a decrease in $k_{cat}$ and an increase in Km. These decreased catalytic activities of CP2601 and CP2616 can be partially attributed to the changes in substrate affinities. These results suggest that the enzymatic activities of CYP4A11 mutants selected from directed evolution using a luminogenic P450 substrate may not demonstrate a direct correlation with the hydroxylation activities of lauric acid.

Identification of Proteins Interacting with C- Terminal Region of Human Ankyrin-G

  • Lee, Yeong-Mi;Lee, Min-A;Park, Jae-Kyoung;Kim, Myong-Shin;Jeon, Eun-Bee;Park, Su-Il;Kim, Chong-Rak
    • Biomedical Science Letters
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    • v.9 no.3
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    • pp.159-165
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    • 2003
  • Ankyrins are a ubiquitously expressed family of intracellular adaptor proteins involved in targeting diverse proteins to specialized membrane domains in both the plasma membrane and the endoplasmic reticulum. Recently, the studies with C-terminus of ankyrins have identified that ankyrin-B is capable of interacting with Hsp40 and sAnkl is capable of interacting with obscurin and titin, but the function of C-terminal domain of ankyrin-G remains unknown. To identify proteins interacting C-terminus of ankyrin-G, we used the C-terminus of ankyrin-G as a bait for a yeast two-hybrid screen of brain cDNA library. Approximately 1.33$\times$l0$^6$ transformants were screened, of which 13 positive clones were obtained as determined by activation of HIS3, ADE2 and MELl reporter genes. Sequence analyses of these 13 plasmids revealed that cDNA inserts of 13 colonies showed highly homologous to 11 genes, including 5 known (i.e., Na$^+$/K$^+$ ATPase $\beta$1, SERBPl, UTF2, cytochrome C oxidase and collagen IV $\alpha$2) and 6 unknown genes. The evaluation of the proteins that emerge from these experiments provides a rational approach to investigate the those proteins significant in interaction with ankyrin-G.

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TNF-induced genes and Proteins

  • 이태호
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1993.11a
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    • pp.17-20
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    • 1993
  • As a step toward a more complete understanding of the molecular actions of TNF, we prepared a cDNA library from TNF-treated human FS-4 fibroblasts and used differential hybridization to identify cDNA clones corresponding to mRNAs enriched in TNF-treated eells. In Quiescent FS-4 cells n induces an increase in the level of some mRNAs within 20 to 30 min. Some of these immediate-early response mRNAs are elevated only transiently for about 30 to 120 min, e. g., c-fos and c-myc (Lin and Vilcek,1987) or the transcription factor IRF-1 (Fujita et al.1989). Such immediate-early gene products may be important for the activation of other genes, but their transient induction suggests that they are not the actual effector molecules responsible for the phenotypic changes induced by TNF. We chose a 3-h incubation with W because we were seeking cDNAs corresponding to messages that are more stably elevated after TNF treatment. Indeed, the results shown in Figure 8 and 9 indicate that all of the mRNAs corresponding to the eight TSG cDNAs isolated remained significantly elevated after 16h of continuous treatment with TNF, and their kinetics of induction were clearly different from those of the immediate-early response mRNAs such as c-fos, c-myc or IRF-1. Nevertheless, only the induction of TSG-21 (collagenase) and TSG-27 (stromelysin) nNAs was completely inhibited by cycloheximide and the induction of TSG-37 (metallothionein-II) was reduced in the presence of this inhibitor of protein synthesis. Induction of the other five TSG mRNAs by TNF was completelyresistant to cycloheximide, suggest ins that no protein intermediate is needed for the upregulation of these mRNAs.

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