• Title/Summary/Keyword: Cell Resistance

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Effect of $H_2O_2$ on Alveolar Epithelial Barrier Properties (폐상피세포 장벽에 대한 $H_2O_2$의 영향)

  • Suh, Duk-Joon;Cho, Se-Heon;Kang, Chang-Woon
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.3
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    • pp.236-249
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    • 1993
  • Background: Among the injurious agents to which the lung airspaces are constantly exposed are reactive species of oxygen. It has been widely believed that reactive oxygen species may be implicated in the etiology of lung injuries. In order to elucidated how this oxidant causes lung cell injury, we investigated the effects of exogenous $H_2O_2$ on alveolar epithelial barrier characteristics. Methods: Rat type II alveolar epithelial cells were plated onto tissue culture-treated polycarbonate membrane filters. The resulting confluent monolayers on days 3 and 4 were mounted in a modified Ussing chamber and bathed on both sides with HEPES-buffered Ringer solution. The changes in short-circuit current (Isc) and monolayer resistance (R) in response to the exogenous hydroperoxide were measured. To determine the degree of cellular catalase participation in protection against $H_2O_2$ injury to the barrier, experiments were repeated in the presence of 20 mM aminotriazole (ATAZ, an inhibitor of catalase) in the same bathing fluid as the hydroperoxide. Results: These monolayers have a high transepithelial resistance (>2000 ohm-$cm^2$) and actively transport $Na^+$ from apical fluid. $H_2O_2$(0-100 mM) was then delivered to either apical or basolateral fluid. Resulting indicated that $H_2O_2$ decreased Isc and R gradually in dose-dependent manner. The effective concentration of apical $H_2O_2$ at which Isc (or R) was decreased by 50% at one hour ($ED_{50}$) was about 4 mM. However, basolateral $H_2O_2$ exposure led to $ED_{50}$ for Isc (and R) of about 0.04 mM. Inhibition of cellular catalase yielded $ED_{50}$ for Isc (and R) of about 0.4 mM when $H_2O_2$ was given apically, while $ED_{50}$ for basolateral exposure to $H_2O_2$ did not change in the presence of ATAZ. The rate of $H_2O_2$ consumption in apical and basolateral bathing fluids was the same, while cellualr catalase activity rose gradually with time in culture. Conclusion: Our data suggest that basolateral $H_2O_2$ may affect directly membrane component (e.g., $Na^+,\;K^+$-ATPase) located on the basolateral cell surface. Apical $H_2O_2$, on the other hand, may be largely degraded by catalase as it passes through the cells before reaching these membrane components. We conclude that alveolar epithelial barrier integrity as measured by Isc and R are compromised by $H_2O_2$ being relatively sensitive to basolateral (and insensitive to apical) $H_2O_2$.

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Effects of Depth and Duration of Flooding on Growth and Yield at Transplanting Stages in Tomato(Lycopersicon esculentum). (토마토(Lycopersicon esculentum)의 이식기(移植期) 침수(浸水) 처리(處理)에 따른 생육(生育) 반응(反應))

  • Guh, Ja-Ock;Roh, Sang-Eun;Kuk, Yong-In;Chon, Sang-Uk;Lee, Young-Man;Oh, Yun-Jin
    • Korean Journal of Environmental Agriculture
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    • v.16 no.1
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    • pp.7-13
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    • 1997
  • Tomatoes are flooded differently 0, 5, 10 and 15 ㎝, according to the developing stages such as transplanting stage under the condition of green house. Along with this, they are treated according to the time condition such as 6, 12, 24, 48 and 120 hours. The results obtained are summarized as follows. As the depth of flooding got deeper and the hours got longer, plant height, number of leaves, shoot and root decreased significantly. Flowering was possible for 24 hours in the flooding of 0 ㎝, for 6 hours in $5{\sim}10$ ㎝, but not possible after 6 hours in 15 ㎝. Without regard to the depth of flooding, adventitious root came into being before or after 48 hours of the treatment. Root activity diminished gradually as hours of treatment went by, but diminished rapidly over the depth of 5 ㎝. Chlorophyll content decreased similarly as in the case of root activity. Diffusion resistance of stomata cell increased as hours of treatment passed and depth increased. Photosynthesis and respiration diminished according as the hours and depth of treatment increased. Respiration diminished a little gradually but photosynthesis weakened greatly as the depth of treatment became greater and after 48 hours of treatment. Diseases occurred remarkably in proportion to the depth of treatment and the increase of hours. The possibility of preventing by means of insecticide treatment showed the same tendency as in the seedling stage. But its effect was not significant. After 120 hours yields could not be expected because tomatoes died without regard to the depth of flooding. Instead of the depth, numbers of fruits per plant decrease of individuals or variation of average weight of a fruit was recognized. Especially average weight increased in accordance with the increase of the depth. There was positive correlation between all the characters, such as plant height, number of leaves, fresh weight, chlorophyll content, root activity and yield traits, but negative correlation between these and epinastic curvature, diffusion resistance and adventitious root.

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Effects of Depth and Duration of Flooding on Growth and Yield at Flowering Stage in Tomato(Lycopersicon esculentum). (토마토(Lycopersicon esculentum)의 개화기 침수 처리에 따른 생육 반응)

  • Guh, Ja-Ock;Han, Sung-Uk;Kuk, Yong-In;Chon, Sang-Uk;Lee, Young-Man
    • Korean Journal of Environmental Agriculture
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    • v.16 no.2
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    • pp.130-135
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    • 1997
  • Tomatoes are flooded differently 0, 5, 10 and 15cm, according to the developing stages such as flowering stage under the condition of greenhouse. Along with this, they are treated according to the time condition such as 6, 12, 24, 48 and 120 hours. The results obtained are summarized as follows. Plant height decreased in the depth of $0{\sim}10cm$ for over 48 hours, in the depth of 15cm for over 24 hours. Number of leaves was the same as in control, and it decreased over. Number of flowers and fruit setting of individuals decreased conspicuously according as the depth and the hours got greater and longer. Adventitious root occurred remarkably in the depth of $0{\sim}10cm$, for over 24 hours and in the depth of 15cm, 12 hours. Epinastic curvature increased greatly as the depth and the hours got greater and longer. Diffusion resistance of stomata cell increased as the depth and the hours got greater and longer. Diseases occurred conspicuously as the hours of flooding got longer rather than as the depth greater. The preventing of diseases caused by insecticide was observed, but it was not greater than in the seedling and transplanting stage. Fertilization was effective in the case of increasing the weight of shoot. Number of fruits per plant did not decrease in the depth of 0cm up to 24 hours, but decreased on the deeper level of flooding and increased as the hours got longer. Moreover with the exception of 120 hours per respective depth of the treatment, average weight of a fruit got greater as the depth and the hours got greater and longer. In the case of epinastic curvature and diffusion resistance, there was negative correlation between all the other investigated characters and positive correlation between weight of a fruits and average weight of a fruit.

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Pathogen, Insect and Weed Control Effects of Secondary Metabolites from Plants (식물유래 2차 대사물질의 병충해 및 잡초 방제효과)

  • Kim, Jong-Bum
    • Applied Biological Chemistry
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    • v.48 no.1
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    • pp.1-15
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    • 2005
  • Pathogens, insects and weeds have significantly reduced agricultural productivity. Thus, to increase the productivity, synthetic agricultural chemicals have been overused. However, these synthetic compounds that are different from natural products cannot be broken down easily in natural systems, causing the destruction of soil quality and agricultural environments and the gradually difficulty in continuous agriculture. Now agriculture is faced with the various problems of minimizing the damage in agricultural environments, securing the safety of human health, while simultaneously increasing agricultural productivity. Meanwhile, plants produce secondary metabolites to protect themselves from external invaders and to secure their region for survival. Plants infected with pathogens produce antibiotics phytoalexin; monocotyledonous plants produce flavonoids and diterpenoids phytoalexins, and dicotylodoneous plant, despite of infected pathogens, produce family-specific phytoalexin such as flavonoids in Leguminosae, indole derivatives in Cruciferae, sesquitepenoids in Solanaceae, coumarins in Umbelliferae, making the plant resistant to specific pathogen. Growth inhibitor or antifeedant substances to insects are terpenoids pyrethrin, azadirachtin, limonin, cedrelanoid, toosendanin and fraxinellone/dictamnine, and terpenoid-alkaloid mixed compounds sesquiterpene pyridine and norditerpenoids, and azepine-, amide-, loline-, stemofoline-, pyrrolizidine-alkaloids and so on. Also plants produces the substances to inhibit other plant growths to secure the regions for plant itself, which is including terpenoids essential oil and sesquiterpene lactone, and additionally, benzoxazinoids, glucosinolate, quassinoid, cyanogenic glycoside, saponin, sorgolennone, juglone and lots of other different of secondary metabolites. Hence, phytoalexin, an antibiotic compound produced by plants infected with pathogens, can be employed for pathogen control. Terpenoids and alkaloids inhibiting insect growth can be utilized for insect control. Allelochemicals, a compound released from a certain plant to hinder the growth of other plants for their survival, can be also used directly as a herbicides for weed control as well. Therefore, the use of the natural secondary metabolites for pest control might be one of the alternatives for environmentally friendly agriculture. However, the natural substances are destroyed easily causing low the pest-control efficacy, and also there is the limitation to producing the substances using plant cell. In the future, effects should be made to try to find the secondary metabolites with good pest-control effect and no harmful to human health. Also the biosynthetic pathways of secondary metabolites have to be elucidated continuously, and the metabolic engineering should be applied to improve transgenics having the resistance to specific pest.

A STUDY OF NI-RESISTANT BACTERIA ON THE RESTORED STAINLESS STEEL CROWN (기성금관 수복어린이에서의 니켈내성균에 관한 연구)

  • Chung, Sat-Byul;Lee, Keung-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.27 no.2
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    • pp.274-282
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    • 2000
  • Stainless steel crowns are widely used for restoration for primary molars. The material used for the crowns is an alloy of $70\sim80%$ nickel and $5\sim15%$ chromium. Nickel has been known to cause allergic reaction, cancer and cell toxicity. Little is known about nickel with respect to the relationship between Ni-contained SS crown and graining of Ni-resistance in oral microorganisms. The purpose of this study is to examine whether use of Ni-contained SS crown leads to occurrence of Ni-resistant microorganism, especially enterococci. The gingival crevicular fluid of two different groups was taken. Experimental group included patients wearing SS crown, and control group comprised individuals without SS crown. The samples were plated in BHI agar, BHI agar supplemented with nickel chloride at the concentration of 3mM and bile esculin azide (BEA) agar. The cultured enterococci on BEA agar medium were tested their Ni-resistance in nickel-containing media increasing concentrations from 3mM to 50mM. The results were as follows: 1. In experimental group, a total of 507,350 strains were isolated on BHI agar, of which 53,864(10.62%) strains were found to be resistant to 3mM nickel. In control group, of 414,590 isolates on BHI agar, 37,523 isolates were resistant to 3mM nickel. 2. A total of 95 enterococci were isolated on BEA agar in experimental group, while 20 were isolated in control group. of the enterococci, 68 and 12 isolates were found to be nickel-resistant in experimental and control group, respectively. 3. Of 68 nickel-resistant isolates in experimental group, one survived 50mM nickel. In contrast, none of the isolates in control group was observed to grow at the concentrations over 30mM nickel.

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Introduction and Expression of PAP gene using Agrobacterium in Scrophularia buergeriana Miquel (Agrobacterium을 이용한 PAP 유전자의 현삼으로 도입 및 형질발현)

  • Yu, Chang-Yeon;Seong, Eun-Soo;Lim, Jung-Dae;Huang, Shan-Ai;Chae, Young-Am
    • Korean Journal of Medicinal Crop Science
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    • v.9 no.2
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    • pp.156-165
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    • 2001
  • Exogeneous application of pokeweed antiviral protein (PAP), a ribosomal-inacivating protein in the cell wall of Phytolacca americana (pokeweed) protects heterologous plants from viral and fungal infection. A cDNA clone of PAP introduced into Scrophularia buergeriana Miquel by thransformation with Agrobacterium tumefaciences. For plant transformation, explants were precultured on shoot induction medium without kanamycin for 2-5 day, and then they were cocultured with Agrobacterium for 10 minutes. The explants were placed on co culture medium in dark condition, $28^{\circ}C$ for 2days. After explants were washed in MS liquid medium, they were transferred into selection medium including kanamycin 50mg/L (MS salts+1mg/ l BAP+2mg/ l TDZ+0,2mg/ l NAA+MS vitamin+3% sucrose+0.8% agar, pH5.8). From PCR analysis, NPT II band was confirmed in transgenic plant genome and showed resistance against fungi in antifungal activity test. Micro assay to which protein extracted from transgenic line were added, revealed hyphae growth inhibition and no spore germination at high concentration. The characteristics of inhibited hyphae was represented transparent and thin. Expression of PAP in transgenic plants offers the possibility of developing resistance to viral and fungal infection.

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Effect of Inhibition Macrophage Migration Inhibitory Factor Activation by Hominis Placenta Herbal Acupuncture on Rheumatic Arthritis (자하차약침(紫河車藥鍼)의 MIF 활성 억제를 통한 LPS 유발 류마티스성 관절염의 치료 효과)

  • Hwang, Ji-Hye;Cho, Hyun-Seok;Lee, Hyun-Jin;Lee, Dong-Gun;Jeong, Won-Je;Jung, Chan-Yung;Kim, Kyung-Ho
    • Journal of Acupuncture Research
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    • v.25 no.3
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    • pp.41-51
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    • 2008
  • Objectives : This study is to evaluate Effect of Inhibition Macrophage Migration Inhibitory Factor(MIF) activation by Hominis Placenta Herbal Acupuncture(HPA) on Rheumatic Arthritis(RA). Hominis Placenta is the placenta of healthy human, which is vital-strengthening medical stuff. In recent years, Hominis Placenta applied to chronic diseases because it makes us more resistance to diseases. Therefore it is supposed that HPA is effective on RA, a kind of autoimmune disease. When RA is induced, MIF is activated, too. MIF affects the process of inflammatory disease including RA. Methods : In order to investigate the effect of Hominis Placenta extraction on MIF(early RA inducing cytokine) and MMP(Matrix Metallo Proteinase)-9 mRNA expression by means of Reverse Transcriptase- Polymerase Chain Reaction(RT-PCR). In this study, we investigated the effect of Hominis Placenta extraction on MIF(early RA inducing cytokine) and MMP-9 mRNA expression by means of RT-PCR. Besides we investigated changing of MIF in synovial membrane and, Interleukin-6 receptor(IL-6R)-$\alpha$(pro-inflammatory cytokine), Signal transducers and activators of transcription(STAT)-3, MMP-9 after treating mouse, which is artificially attacked with RA, with HPA on its $ST_{35}$, LE201 in vivo. Results : 1. As a result of treating Lipopolysaccharide(LPS)-stimulated Raw246.7cell with HPA, MIF(RA related cytokine) and MMP-9 mRNA expression is reduced in vitro. And this reaction is concentration-dependatant. 2. In synovial membrane of the mice treated with HPA, inhibition of MIF, IL-6R-$\alpha$, STAT3 & MMP-9 activation is observed in vivo. Conclusions : From the above results, it might be suggested that HPA mitigate tissue damage originated from RA, because it intercepts the early process of by inhibition MIF activity.

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Design of Low-Noise and High-Reliability Differential Paired eFuse OTP Memory (저잡음 · 고신뢰성 Differential Paired eFuse OTP 메모리 설계)

  • Kim, Min-Sung;Jin, Liyan;Hao, Wenchao;Ha, Pan-Bong;Kim, Young-Hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.10
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    • pp.2359-2368
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    • 2013
  • In this paper, an IRD (internal read data) circuit preventing the reentry into the read mode while keeping the read-out DOUT datum at power-up even if noise such as glitches occurs at signal ports such as an input signal port RD (read) when a power IC is on, is proposed. Also, a pulsed WL (word line) driving method is used to prevent a DC current of several tens of micro amperes from flowing into the read transistor of a differential paired eFuse OTP cell. Thus, reliability is secured by preventing non-blown eFuse links from being blown by the EM (electro-migration). Furthermore, a compared output between a programmed datum and a read-out datum is outputted to the PFb (pass fail bar) pin while performing a sensing margin test with a variable pull-up load in consideration of resistance variation of a programmed eFuse in the program-verify-read mode. The layout size of the 8-bit eFuse OTP IP with a $0.18{\mu}m$ process is $189.625{\mu}m{\times}138.850{\mu}m(=0.0263mm^2)$.

Therapeutic Strategy for the Prevention of Pseudorabies Virus Infection in C57BL/6 Mice by 3D8 scFv with Intrinsic Nuclease Activity

  • Lee, Gunsup;Cho, SeungChan;Hoang, Phuong Mai;Kim, Dongjun;Lee, Yongjun;Kil, Eui-Joon;Byun, Sung-June;Lee, Taek-Kyun;Kim, Dae-Hyun;Kim, Sunghan;Lee, Sukchan
    • Molecules and Cells
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    • v.38 no.9
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    • pp.773-780
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    • 2015
  • 3D8 single chain variable fragment (scFv) is a recombinant monoclonal antibody with nuclease activity that was originally isolated from autoimmune-prone MRL mice. In a previous study, we analyzed the nuclease activity of 3D8 scFv and determined that a HeLa cell line expressing 3D8 scFv conferred resistance to herpes simplex virus type 1 (HSV-1) and pseudorabies virus (PRV). In this study, we demonstrate that 3D8 scFv could be delivered to target tissues and cells where it exerted a therapeutic effect against PRV. PRV was inoculated via intramuscular injection, and 3D8 scFv was injected intraperitoneally. The observed therapeutic effect of 3D8 scFv against PRV was also supported by results from quantitative reverse transcription polymerase chain reaction, southern hybridization, and immunohistochemical assays. Intraperitoneal injection of 5 and $10{\mu}g$ 3D8 scFv resulted in no detectable toxicity. The survival rate in C57BL/6 mice was 9% after intramuscular injection of 10 $LD_{50}$ PRV. In contrast, the 3D8 scFv-injected C57BL/6 mice showed survival rates of 57% ($5{\mu}g$) and 47% ($10{\mu}g$). The results indicate that 3D8 scFv could be utilized as an effective antiviral agent in several animal models.

An Application of the Multi-slope MUSCL to the Shallow Water Equations (천수방정식에 대한 다중 경사 MUSCL의 적용)

  • Hwang, Seung-Yong;Lee, Sam-Hee
    • Journal of Korea Water Resources Association
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    • v.44 no.10
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    • pp.819-830
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    • 2011
  • The multi-slope MUSCL, proposed by T. Buffard and S. Clain, determines slopes of conserved variables at each edge of a cell in the linear reconstructions of data. In this study, the second order accurate numerical model was developed according to the multi-slope MUSCL to solve the shallow water equations on the unstructured grids. The HLLL scheme of approximate Riemann solvers was used to calculate fluxes. For the review of the applicability of the developed model, the results of the model were compared to the 'isolated building test' and the 'model city flooding experiment' conducted as part of the IMPACT (Investigation of extreMe flood Processes And unCerTainty) project in Europe. There were limitations to predict abrupt rising of water depths by the resistance of model buildings and water depths at the specific locations among the buildings. But they were identified as the same problems also revealed in results of the other models to the same experiment. On the more refined meshes to the 'model city flooding experiment' simulated results showed good agreement with measurements. It was verified that the developed model simulated well the complex phenomena such as a dam-break problem and the urban inundation by flash floods.