• Journal of Plant Biotechnology
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• v.6 no.4
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• pp.221-227
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• 2004

Protocol was established for production of virus free healthy seeds using meristem ($0.3-0.5\;\cal{mm}$ in size) culture and field management under net house condition in tomato. The isolated meristem was found well established in MS liquid medium containing $0.1\;\cal{mg}\;1^{-1}\;of\;GA_3$. For shoot and root development either from primary meristem or from nodal segment of meristem derived plants, semisolid MS medium having $0.5\;\cal{mg}\;1^{-1}$ of IBA was found most effective. The elimination of the studied viruses (ToMV, CMV, ToLCV) in meristem-derived plants was confirmed by DAS-ELISA test. For field management of the virus eradicated meristem-derived plants, use of net house was found very effective measures to check viral vector visit and eventually infection. The meristem-derived plants were vigor and high yielder than the native seed derived plants and produced healthy seeds. Due to stop vector visit, no viral symptoms were observed in both $R_1\;and\;R_2$ plants cultivated in net house condition. Starting of viral infestation was observed in $R_2$ generation when they were planted in open house condition without control of vector visit. Therefore, for management of viral diseases, use of virus free meristem derived plantlets and their subsequent cultivation in soil under net house condition without using any vector killing insecticide can be recommended for producing healthy seeds in tomato. The developed protocol for environmentally healthy tomato seed production in Bangladesh may be used in the countries having similar tropical like environment conducive for viral vector visit.

• The Journal of Korean Society for School & Community Health Education
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• v.12 no.1
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• pp.103-116
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• 2011

Objective: The study analyzed degrees of participation in physical activities, demographic and sociological characteristics of middle and high school students, and the relations to mental health related factors, based on "Korea youth risk behavior web-based survey." Therefore, the study can be used as preliminary data for establishing mental health promotion plans for youth and setting contents and directions of health education. Methods: The study analyzed the data, collecting from 75,066 middle and high school students, regarding their demographic and sociological characteristics, mental health, and relations to physical activities by using SPSS Win 15.0. Results: 19.1% of the students answered they had seriously contemplated suicide during the past 12 months, and 43.2% said they are usually under enormous pressure. 55.3% answered that academic achievements and the pressure from future paths are major factors of their stress. The students showed noteworthy differences in whether they think about suicide depending on whether the students live with their father or mother. The study found that the students whose parents' levels of education are low, or their academic records are low, or economic conditions are poor are more likely to think about suicide. The students tend to think more about killing themselves if they spend more time sitting to study than being engaged in physical activities, or spend little time walking. And they are more likely to think about committing suicide if they spend little time exercising, or are not engaged in physical activities on the playground or a gym in PE classes.

• Journal of Acupuncture Research
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• v.17 no.3
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• pp.176-187
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• 2000

Objectives : This study was purposed to investigate the antioxidative effects of Paeoniae radix aqua-acupuncture solution(PR) on culture liver cell system, lipid peroxidation and antioxidative enzyme activities in tert-butyl hydroperoxide(t-BHP) treatmented conditions. Methods : Cultured normal rat liver cell(Ac2F) were prepared and incubated with or without PR(at 2% volume in culture medium). After 16~18hr, cells placed in DMEM medium without serum, and then incubated with 1mM t-BHP for 2hr. Viable cells were detected by MTT assay, and the levels of lipid peroxide(LPO) were measured by TBA method. And catalase activity was measured as the decrease in hydrogen peroxide absorbance at 240nm on spectrophotometer using 30mM hydrogen peroxide. Superoxide dismutase(SOD) were assayed by recording the inhibition of nitro blue tetrazolium reduction with xanthine and xanthine oxidase. Glutathione peroxidase(GPX) activity was determined by the modified coupled assay developed by Paglia and Lawrence. The reaction was started by addition of 2.2mM hydrogen peroxide as substrate. The change in absorbance at 340nm was measured for 1min on spectrophotometer. Glutathione-S-transferase(GST) activity was assayed with CDNB as substrate and enzyme activity of GST towards the glutathione conjugation of CDNB. Results : Cell killing was significantly enhanced by addition of t-BHP compared to those of untreated group. PR pretreated cell resisted the toxic effects of t-BHP. LPO levels of t-BHP treatment group were significantly higher than other groups. This increased level was significandy reduced by PR pretreatment. The t-BHP treatment resulted in a decrease of catalase, GPX and GST activities. By contrast, PR pretreatment markedly increased compare to those of untreated groups. Conclusions : T-BHP which can produce intracellular free radical was used for inducer of the peroxidation of cellular lipids. PR protected the cell death induced by t-BHP and significantly increased cell viabiliry in the normal rat liver cell, and showed effective inhibition of lipid peroxidation, and elevations of catalase, GPX and GST activities. These results suggested that PR might play a protective role in lipid peroxidation by free radicals.

• Applied Chemistry for Engineering
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• v.34 no.5
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• pp.479-487
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• 2023

Copper is cost-effective and abundantly available as a biocidal coating agent for a wide range of material surfaces. Natural oxidation does not compromise the efficacy of copper, allowing it to maintain antimicrobial activity under prolonged exposure conditions. Furthermore, copper compounds exhibit a broad spectrum of antimicrobial activity against pathogenic yeast, both enveloped and non-enveloped types of viruses, as well as gram-negative and gram-positive bacteria. Contact killing of copper-coated surfaces causes the denaturation of proteins and damage to the cell membrane, leading to the release of essential components such as nucleotides and cytoplasm. Additionally, redox-active copper generates reactive oxygen species (ROS), which cause permanent cell damage through enzyme deactivation and DNA destruction. Owing to its robust stability, copper has been utilized in diverse forms, such as nanoparticles, ions, composites, and alloys, resulting in the creation of various coating methods. This mini-review describes representative coating processes involving copper ions and copper oxides on various material surfaces, highlighting the antibacterial and antiviral properties associated with different oxidation states of copper.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2001.06a
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• pp.149-153
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• 2001

To investigate the mode of bactericidal action for antimicrobial peptide, pediocin, synthetic and mutant pediocins were prepared by direct chemical synthesis. Native pediocin was purified from Pedio-coccus acidilactici M and its conformational structure and bactericidal functions were analyzed and compared to synthetic pediocin. Schematic mode of pediocin actions, how pediocin binds on the target cell membrane, penetrates and makes tunnel are proposed. For these purposes, primary and secondary structures of pediocin was analyzed and disulfide bond assignment was also done. The pediocin purified from P. acidilactici M had high effective bactericidal ability against gram positive bacteria, especially Listeria monocytogenes and was very stable at extreme pHs and even at high temperatures such as autoclaving temperature (121$^{\circ}C$). Pediocin was consisted of 44 amino acids with four cysteines. Novel synthetic peptides were achieved by solid phase peptide synthesis(SPPS) method. To explain the function of cysteine in C-terminal region, mutant pediocin, Ped[C24A＋C44A], was synthesized and their structural and biological functions were analyzed. Second mutant pediocin, Ped[KllE], was prepared to explain the function of lysine at 11 of N-terminal part of pediocin, especially loop of $\beta$-sheet, and to predict the initial binding site of pediocin. The native and synthetic pediocins was showed random coil conformation by spectropolarimetry in moderate conditions. This conformation was observed in extreme conditions such as high temperature and low and high pHs, also. Circular dichroism(CD) data also showed the existence of $\beta$-turn structure in N-terminal part both native and synthetic pediocins. A structural model for pediocin predicts that 18 amino acids in the N-terminal part of the peptide assume a three-strand $\beta$-sheet conformation. This random coil in C-terminal part of pediocin was converted to folding structure, helix structure, in nonpolar solvents such as alcohol and TFE. The disulfide bond between $^{9}$ Cys and $^{14}$ Cys was concrete and inevitable, however, evidences of disulfide bond between $^{24}$ Cys and $^{44}$ Cys was not. Data of Ped[C24A＋C44A], pediocin mutant showed that $^{44}$ Cys was required during killing the target cells but not inevitable, since Ped[C24A＋C44A] still have bactericidal activity but much less than native pediocin. Another pediocin mutant, Ped[KllE], had still bactericidal activity, was controversial to propose that positive charge like as $^{11}$ Lys in loop or hinge in bacteriocin bound or helped to binding to microorganism with electrostatic interaction between cell membrane especially teichoic acid and positive amino acid nonspecifically. The conformation of pediocin among native, synthetic and mutant pediocins did not show big difference. The conformations between oxidized and reduced pediocin were almost similar regardless of native or synthetic.

• The Journal of Korean Academic Society of Nursing Education
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• v.7 no.2
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• pp.196-206
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• 2001

The purpose of this study was to identify Korean adolescents' sexual harassment conditions and patterns in schools as well as their psychological reactions when they are under sexual harassments or they committed sexual harassments. The subjects were 475 middle and high schoolers in Pusan and Gyeong Sang Nam-Do. The survey was executed from July 1 through Dec. 31, 2000. The collected data was analyzed by SPSS WIN 8.0 using percentage, mean. The results of this study were as follows: 1. the linguistic sexual harassment such as 'lewd jokes or dirty talks' was the major pattern(35.4%), The body touching such as 'kiss or embracing', 'internet transmission of pornography', 'sexual harassing of body characteristics', touching breast', 'grasping of hands or body touching', 'body touching in secret place', 'urging to sit in touch or on knees', 'exposing of special body areas', and 'showing pornography' followed in a row. 2. The eighteen point three percents of subjects had the experience to commit sexual harassment. The forty four point seven percent of above subjects committed it against their classmates. The first time to commit sexual harassment was their middle school period (38.4%). Their motives to commit it were as under: 'killing time'(48.8%), 'annoying', 'attracting attention from the other sex', 'expressing lovely emotions', 'urging of their friends', 'misunderstanding that the other partners felt good when they experienced sexual harassment, 'showing their strength' etc. their with committing harassments they felt as under ; 'joyful'(61.6%), 'funny,' 'desirous to try again', 'thrilling', 'breaking stress', very pleasant', 'exciting', 'regretful', 'guilty', and 'feeling fear' etc. 3. Twenty four point two percents of the population exposed to sexual harassments. The sexual harassers were almost their classmates (42.7%). And then unknown people', 'boy or girl friends and school staffs' followed in a row. The places where harassments happened were 'inside classroom'(69.8%), 'school bus and subway', 'outside school', etc. The feelings when experienced harassments were 'anger' (51.3%), 'hurting self-respect', 'embarrassing', 'rejection', 'insulting', 'shame', 'fear', 'dislike', 'anxiety', 'melancholy' etc. The reasons not to have consultations after sexual harassments were 'worrying to be well-known'(49.6%), 'believing not helpful enough', 'regarding simple mischief', 'trying to revenge directly', 'understanding their mistakes', 'worrying retaliation' etc.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.21-24
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• 2004

To determine lethal temperature of alfalfa (Medicago sativa L. cv Vernal) at heat-stressed conditions, seedlings grown in a small pots for 4 weeks were subjected to different temperature regimes of heat treatment. No apparent demage was observed when the plants were treated at 45, 50 or $60^{\circ}C$ for 1 h. Heat treatments at 60 and $65^{\circ}C$ for 1 h, several plants were withered and showed damage symptom on their leaves. When the plants were exposed to $70^{\circ}C$ for 1 h, most of leaves were severely withered, but it was not lethal conditions for the whole plants. By contrast, most of plants were died within one day after heat treatment at $80^{\circ}C$ for 1h. Furthermore, plants exposed to $80^{\circ}C$ for 50 min were also died within 7 days. It was found that new shoots were regenerated from the plants that had been treated at $80^{\circ}C$ within 45 min. These results indicate that heat treatment at $80^{\circ}C$ for 50 min is an optimum condition to distinguish the lethality of alfalfa plants. Simple viability assay system established in this study will be useful fer selection and characterization of heat-tolerant transgenic alfalfa plants.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.25-28
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• 2004

To determine lethal temperature of orchardgrass (Dactylis glomerata L. cv. Janbeol 102) developed in Korea at heat-stressed conditions, seedlings grown in a amall pots for 4 weeks were treated at $45^{\circ}C$, $50^{\circ}C$ or $55^{\circ}C$ for 1 h. Heat treatments at $60^{\circ}C$ and $65^{\circ}C$ for 1 h, several plants were withered and showed damage symptom on their leaves. When the plants were exposed to $70^{\circ}C$ for 1 h, most of leaves were severely withered, but it was not lethal conditions for the whole plants. By contrast, most of plants were died within one day after heat treatment at $80^{\circ}C$ for 1h. Furthermore, plants exposed to $80^{\circ}C$ for 55 min were also died within 7 days. It was found that new shoots were regenerated from the plants that had been treated at $80^{\circ}C$ within 50 min. These results indicate that heat treatment at $80^{\circ}C$ for 55 min is an optimum condition to distinguish the lethality of orchardgrass plants. Simple viability assay system established in this study will be useful for selection and characterization of heat-tolerant transgenic orchardgrass plants.

• Korean Journal of Weed Science
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• v.14 no.4
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• pp.272-279
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• 1994

In order to compare the biological properties of benfuresate and cinosulfuron as herbicides for the chemical control of Eleocharis kuroguwai, some experiments were conducted at greenhouse and field conditions in 1993. Benfuresate and cinosufuron moved to 2cm and 6cm deep in paddy soil and inhibited the growth of E. kuroguwai. Benfuresate was absorbed into the roots of E. kuroguwai. whereas cinosulfuron was absorbed into not only the roots and shoots but also the mesocotyls. After the emergence was inhibited by the soil application of herbicides, the percentage of regrowing numbers was higher at cinosulfuron than at benfuresate, whereas the growth rate was higher at benfuresate on the contrary. Benfuresate brought about complete death of buds as a killing type, but cinosulfuron produced lots of abnormal shoots as an inhibiting type. Benfuresate was able to apply on soil surface from the preemergence to the early stage of 2cm high, but cinosulfuron was able to use from the preemergence to the stage of 15cm high. The foliar application of cinosulfuron showed a good control effect, but it induced a severe phytotoxicity to rice. A good control effect of Benfuresate/bensulfuron GR lowered at the late stage, but that of cinosulfuron/mefenacet/dymron GR at the early stage maintained until the late stage of 65 days after transplanting.

• IMMUNE NETWORK
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• v.3 no.4
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• pp.302-309
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• 2003

Background: CTLA4 (CD152), which is expressed on the surface of T cells following activation, has a much higher affinity for B7 molecules comparing to CD28, and is a negative regulator of T cell activation. In contrast to stimulating and agonistic capabilities of monoclonal antibodies specific to CTLA-4, CTLA4Ig fusion protein appears to act as CD28 antagonist and inhibits in vitro and in vivo T cell priming in variety of immunological conditions. We've set out to confirm whether inhibition of the CD28-B7 costimulatory response using a soluble form of human CTLA4Ig fusion protein would lead to persistent inhibition of alloreactive T cell activation. Methods: We have used CHO-$dhfr^-$ cell-line to produce CTLA4Ig fusion protein. After serum free culture of transfected cell line we purified this recombinant molecule by using protein A column. To confirm characterization of fusion protein, we carried out a series of Western blot, SDS-PAGE and silver staining analyses. We have also investigated the efficacy of CTLA4Ig in vitro such as mixed lymphocyte reaction (MLR) & cytotoxic T lymphocyte (CTL) response and in vivo such as experimental autoimmune encephalomyelitis (EAE), graft versus host disease (GVHD) and skin-graft whether this fusion protein could inhibit alloreactive T cell activation and lead to immunosuppression of activated T cell. Results: In vitro assay, CTLA4Ig fusion protein inhibited immune response in T cell-specific manner: 1) Human CTLA4Ig inhibited allogeneic stimulation in murine MLR; 2) CTLA4Ig prevented the specific killing activity of CTL. In vivo assay, human CTLA4Ig revealed the capacities to induce alloantigen-specific hyporesponsiveness in mouse model: 1) GVHD was efficiently blocked by dose-dependent manner; 2) Clinical score of EAE was significantly decreased compared to nomal control; 3) The time of skin-graft rejection was not different between CTLA4Ig treated and control group. Conclusion: Human CTLA4Ig suppress the T cell-mediated immune response and efficiently inhibit the EAE, GVHD in mouse model. The mechanism of T cell suppression by human CTLA4Ig fusion protein may be originated from the suppression of activity of cytotoxic T cell. Human CTLA4Ig could not suppress the rejection in mouse skin-graft, this finding suggests that other mechanism except the suppression of cytotoxic T cell may exist on the suppression of graft rejection.