• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.1
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• pp.64-70
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• 2011

Nitrate reductase (NR) is activated by nitrogen sources (${NO_3}^-$ and ${NH_4}^+$) and irradiance. This study investigated the effects of these factors on the NR activity of Ulva pertusa (Chlorophyta) and Ecklonia cava (Phaeophyta). In addition, the ammonium (${NH_4}^+$) and nitrate (${NO_3}^-$) uptake rates of the two species were examined. U. pertusa took up most of the ${NO_3}^-$ and ${NH_4}^+$ in the medium during a 3hour incubation, while E. cava had a relatively high uptake rate after 3 hours. The NR activities of the two species were affected by the nitrogen source and irradiance and were highest when they were exposed to ${NO_3}^-$-rich medium and high irradiance. However, the patterns of NR activity differed between the two species. In ${NO_3}^-$-rich medium and high irradiance, U. pertusa achieved the highest NR activity ($2.01{\pm}0.07\;{\mu}mol$ ${NO_2}^-$ $g^{-1}$ DW $h^{-1}$) within the first 3 hours and then this activity decreased drastically. By contrast, the NR activity of E. cava ($0.36{\pm}0.04\;{\mu}mol$ ${NO_2}^-$ $g^{-1}$ DW $h^{-1}$) was constant for 12 hours. When exposed to darkness, the NR activity of U. pertusa decreased dramatically, while that of E. cava increased gradually for 12 hours. Therefore, E. cava is able to maintain NR activity during the dark because of its adequate carbohydrate reserves and substrate.

• Korean Journal of Acupuncture
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• v.22 no.2
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• pp.107-125
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• 2005

Objectives : The aim of this study was to investigate the asthma-suppressive and immuno-regulatory effect of NR-HA(Notopterygii Rhizoma Herbal-acupuncture) at Pyesu(BL13) on OVA(ovalbumin)-induced asthma in mice. Methods : C57BL/6 mice out of all the experimental sloops, except the Normal group and the NR-HA group, were sensitized and challenged with OVA. The mice in the NR-HA group and the OVA-NR-HA group were treated with NR-HA(1%) at Pyesu(BL13). The mice in the OVA-Saline group were injected with saline at Pyesu(BL13). The mice in the OVA-Needle-prick group were treated with a single prick with an injection needle at Pyesu(BL13). NR-HA, saline injection and needle prick were administered for 8 weeks, three times a week Results : in vitro 1. The populations of granulocytes, $CD3e^-/CCR3^+$cells, $CD69^+/CD3e^+$ cells, $CD4^+\;cells\;and\;CD23^+/B220^+$ cells in the OVA-induced asthmatic mouse lungs decreased significantly by NR-HAS(Notopterygii Rhizoma Herbal-acupuncture solution). 2. The lung weight and total cells in lung of the OVA-NR-HA group decreased significantly compared with those of the OVA-Control group. 3. Total leukocytes and eosinophils in BALF of the OVA-NR-HA group decreas ed significantly compared with those of the OVA-Control group. 4. The collagen accumulation in the lung sections of the OVA-NR-HA group decreased significantly compared with that of the OVA-control group. 5. The concentrations of IL-4, IL-5, IL-13, IgE in BALF and serum of the OVA-NR-HA group decreased significantly compared with those of the OVA- Control group. 6. The numbers of $Gr-1^+/CD11b^+,\;CCR3^+,\;CD3e^+, \;CD19^+,\;CD3e^+/CD69^+$ cells in the OVA-NR-HA group decreased significantly compared with those of the OVA-Control group. 7. The mRNA expressions of $TNF-{\alpha}$, IL-5, IL-4 and IL-13 in lung of the OVA-NR-HA group decreased significantly compared with those of the OVA- Control group. 8. The NR-HA group did not show my considerable difference from the Normal group. The OVA-saline group and the OVA-Needle prick group showed suppressive effects on OVA-induced asthma however they were not statistically significant. Conclusion : These results suggest that NR-HA at Pyesu(BL13) is considered to be effective in treating asthma and to be put to practical use in the future asthma clinic.

• Korean Journal of Microbiology
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• v.35 no.3
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• pp.197-204
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• 1999

A total of 22 Leptospiua inlermgans field isolates from the ~ a t s captured in 5 provinces of Korea in 1996, and 6 antigenically closely related relerence serovars of lai, yeonchon, birkini. gem, mwogolo. and canicola were analysed. When the antigenic characteristics were analysed by reactivity with 7 monoclonal antibodies prepared with sh.ains belongng to serogroup Icterohaemorrhagiae. all 22 isolates showed the same reaction pattern with that of serovar lai. Large restriction fragment patterns obtained after cleavage of geno~nic DNAs with infrequently cuttimg restriction enzymes were analyzed by pulsed-field pel electrophoresis(PFGE). Identification of leptospira strains by PFGE with Nor I, Asc I or Iise I digests correlated with their antigenically typed serovars, silh a few exceptions. PFGE of isolates, except for JR89, digested wjth Nor I showed identical pattern w~th serovar lai, showing 13 Cragments between 940 kb and 63 kb. When PFGE pallerns of JR89 were compared with those of serovar lai, Not I digest showed additional two hands of 1000 kb and 460 kb, while Asc I digest showed 650 kb fragment and Fse I digest did not show the fragment of 280 kb. Whereas serovar yeonchon. which was isolated in Korea and identified as a new serovar previously. could be differentiated from serovar lai in antigenic reactivities with monoclonal antibodres. it showed the similar PFGE pattern with serovar lai includin~ reference and field isolates. It was suggested that Korean leptospiral field isolates are closely related in DNA level.

• Journal of Ecology and Environment
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• v.47 no.3
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• pp.118-133
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• 2023

Background: Free-living amoebae (FLA) are widely distributed in freshwater, seawater, soil, and extreme environments, and play a critical role as feeders on diverse preys in the ecosystem. Also, some FLA can become opportunistic pathogens in animals including humans. The taxa Amoebozoa and Heterolobosea are important amoeboid groups associated with human pathogens. However, the identification and habitat of amoebae belonging to Amoebozoa and Heterolobosea remain poorly reported in the Republic of Korea. This study highlights the first record for identification and source of four amoebae including putative pathogens in the Republic of Korea. Results: In the present study, four previously reported FLA were isolated from freshwaters in Sangju Gonggeomji Reservoir (strain GO001), one of the largest reservoirs during the Joseon Dynasty period, and along the Nakdong River, the largest river in the Republic of Korea (strains NR5-2, NR12-1, and NR14-1) for the first time. Microscopic observations and 18S rDNA phylogenetic trees revealed the four isolated strains to be Acanthamoeba polyphaga (strains NR5-2 and NR12-1), Tetramitus waccamawensis (strain GO001), and Naegleria australiensis (strain NR14-1). Strains NR5-2 and NR12-1 might be the same species and belonged to the morphological Group 2 and the T4 genotype of Acanthamoeba. Strain GO001 formed a clade with T. waccamawensis in 18S rDNA phylogeny, and showed morphological characteristics similar to previously recorded strains, although the species' flagellate form was not observed. Strain NR14-1 had the typical morphology of Naegleria and formed a strongly supported clade with previously recorded strains of N. australiensis in phylogenetic analysis of 18S rDNA sequences. Conclusions: On the bases of morphological and molecular analyses, four strains of FLA were newly observed and classified in the Republic of Korea. Three strains belonging to the two species (A. polyphaga and N. australiensis) isolated from the Nakdong River have the potential to act as opportunistic pathogens that can cause fatal diseases (i.e. granulomatous amoebic encephalitis, Acanthamoeba Keratitis, and meningoencephalitis) in animals including humans. The Nakdong River in the Republic of Korea may provide a habitat for potentially pathogenic amoebae, but additional research is required to confirm the true pathogenicity of these FLA now known in the Republic of Korea.

• Elastomers and Composites
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• v.7 no.2
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• pp.183-192
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• 1972

As a series of tile studies of EPDM-Polymer blends, tile experiment are concentrated to the investigation of the physical properties of tile EPDM-NR-SBR blends. The results are shown as follows: 1. In blending, tensile strength decreased with increase in EPDM contents, especially the ratio of EPDM/NR-SBR is 75/25. 2. Elongation and tear strength were much influenced by blending, especially the ratio of EPDM/NR-SBR is 50/50. 3. Ozone resistance is much improved after blending. It was effective more than tile ratio of EPDM/NR-SBR is 25/75. 4. Aging resistance is much improved after blending. It was effective more than the ratio of EPDM/NR-SBR is 50/50. 5. Hardness increased with increase in EPDM contents and on the other hand, abrasion resistance decreased.

• The Korean Journal of Food And Nutrition
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• v.13 no.5
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• pp.460-464
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• 2000

We have evaluated cytotoxic effects of four crude extracts of methylene chloride, ethyl acetate, butanol, water layer isolated Rheum undulatum in A498 cell line, human kidney epithelial cells. The cytotoxic evalutation was measured by colorimetric assay using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide(MTT) , neutral red(NR) and sulforhodamine protein B(SRB). These results obtained are as follows : MTT, NR and SRB quantities were significantly decreased in cultured A498 cells treated four crude extracts by increased concentrations. The cell cytotoxic effect of crude extracts of butanol layer was more stronger than others layer. The values of MTT$\sub$50/, NR$\sub$50/, SRB$\sub$50/ of crude extract of butanol layer and were measured both 0.63 mg/ml, 0.65 mg/ml, and 0.68 mg/ml, respectively and the values of water layer were 0.84 mg/ml, 0.82 mg/ml. and 0.80 mg/ml. respectively in cultured A498 cell line.

• Korean journal of applied entomology
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• v.21 no.2 s.51
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• pp.87-94
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• 1982

The mymarids egg parasite of rice planthopper, Anagrus nr. flaveolus, were investigated to know their parasitic activities after overwitering in the paddy banks and barley fields, their host preferences and seasonal variations in the pesticide sprayed and unsprayed paddy fields of Gyeongnam province O.R.D. at Jinju from 1977 to 1979. The parasitic activities of Anagrus nr. flaveolus after overwintering in the paddy banks were high early in April and tended to decrease remarkably since mid-April by moving to the barley fields. The parasitic rate of Anagrus nr. flavelous was $47.2\~88\%$ between middle and late in April, the peak of egg deposition period. Anagrus nr. flaveolus parasitized Laodelphax striatellus, Nilaparvata lugens, and Sogatella furcifera, but didn't attack the eggs of Nephotettix cincticeps in the paddy fields. High preference was observed with Laodelphax steriatellus. The parasitic activities of Anagrus nr. flaveolus in the pesticide sprayed paddy fields were high in early July and from late August to early September. The parasitic rate in the pesticide unsprayed fields were higher than those of sprayed fields during the pesticide spraying period, from July to August and parasitic activities were active from October to before coming winter.

• Korean Journal of Acupuncture
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• v.22 no.2
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• pp.89-105
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• 2005

Objective & Methods : This study is performed to observe the effect of Herbal-acupuncture with Notopterygii Radix Herbal-Acupuncture Solution(NR-HAS) at Joksamni(ST36) on Collagen II-induced arthritis (CIA) in DBA/1J mice. Result : 1. The highest survival rate of mice lung fibroblasts were measured in the 1% NR-HAS, and the expression of $TNF-{\alpha}$ in synovial cells were significantly decreased in the 1% and 10% NR-HAS. 2. The incidence of arthritis and the spleen weight were significantly decreased by Notopterygii Radix Herbal-acupuncture(NR-HA) at ST36. 3. The levels of IL-6, $INF-{\gamma},\;TNF-{\alpha}$, IgG, IgM, anti-collagen II in serum of CIA mice were significantly decreased by NR-HA at ST36. 4. In histology, the cartilage destruction and synovial cell proliferation were decreased by NR-HA at ST36, and the collagen fiber expressions in the NR-HA I II groups were similar with that of the normal group. 5. In lymph node, the expression ratios of $CD3e^+\;to\;CD19^+$ cell and $CD4^+\;to\;CD8^+$ cell in the NR-HA I II groups were similarly maintained as those in the normal group. 6. In lymph node, $CD69^+/CD3e^+$ cells and $CD11a^+/CD19^+$ cells were decreased by NR-HA at ST36. 7. In the articular joint, $CD11b^+/Gr-1^+$ cells were decreased by NR-HA at ST36. 8. NR-HA at ST36 did not make a considerable difference in DBA/1J mice without CIA 9. Throughout the overall experimental result, NR-HA I group showed more predominant effect than the NR-HA II group. Conclusion : These results suggest that NR-HA at ST36 has an effect to control synovial cell proliferation and cartilage destruction in rheumatoid arthritis, as well as prophylaxis is important to treat rheumatoid arthritis in clinic.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.208-217
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• 2011

The effects of pH and temperature on the removal of two dyes (neutral red; NR and malachite green oxalates; MG) from aqueous effluents using Maghnia montmorillonite clay in a batch adsorption process were investigated. The results showed the stability of the optical properties of MG in aqueous solution and adsorbed onto clay under wide range of pH 3-9. However, the interaction of NR dye with clay is accompanied by a red shift of the main absorption bands of monomer cations under pH range of 3-5, whereas, those of neutral form remains nearly constant over the pH range of 8-12. The optimal pH for favorable adsorption of the dyes, i.e. ${\geq}$90% has been achieved in aqueous solutions at 6 and 7 for NR and VM respectively. The most suitable adsorption temperatures were 298 and 318 K with maximum adsorption capacities of 465.13mg/g for NR and 459.89 mg/g for MG. The adsorption equilibrium results for both dyes follow Langmuir, Freundlich isotherms. The numerical values of the mean free energy $E_a$ of 4.472-5.559 kj/mol and 2.000-2.886 kj/mol for NR and MG respectively indicated physical adsorption. Various thermodynamic parameters, such as ${\Delta}H^{\circ}$, ${\Delta}S^{\circ}$, ${\Delta}G^{\circ}$ and Ea have been calculated. The data showed that the adsorption process is spontaneous and endothermic. The sticking probability model was further used to assess the potential feasibility of the clay mineral as an alternative adsorbent for organic ion pollutants in aqueous solution.

• Journal of Microbiology and Biotechnology
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• v.21 no.2
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• pp.154-161
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• 2011

L. lactis sk071115 has been shown to grow more actively and generate lower levels of lactate in glucose-defined medium with nitrate than in medium with Mn(IV). By adding Mn(IV) to a L. lactis culture, lactate production was relatively reduced in combination with Mn(II) production, but cell mass production levels did not increase. Both cell-free extract and intact L. lactis cells reacted electrochemically with Mn(IV) but did not react with Mn(II) upon cyclic voltammetry using neutral red (NR) as an electron mediator. A modified graphite felt cathode with NR (NR-cathode) was employed to induce electrochemical reducing equivalence for bacterial metabolism. Cell-free L. lactis extract catalyzed the reduction of Mn(IV) to Mn(II) under both control and electrochemical reduction conditions; however, the levels of Mn(II) generated under electrochemical reduction conditions were approximately 4 times those generated under control conditions. The levels of Mn(II) generated by the catalysis of L. lactis immobilized in the NR-cathode (L-NR-cathode) under electrochemical reduction conditions were more than 4 times that generated under control conditions. Mn(II) production levels were increased by approximately 2.5 and 4.5 times by the addition of citrate to the reactant under control and electrochemical reduction conditions, respectively. The cumulative Mn(II) produced from manganese ore by catalysis of the L-NR-cathode for 30 days reached levels of approximately 3,800 and 16,000 mg/l under control and electrochemical reduction conditions, respectively. In conclusion, the electrochemical reduction reaction generated by the NR-cathode activated the biochemical reduction of Mn(IV) to Mn(II) by L. lactis.