• Journal of Pharmaceutical Investigation
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• v.13 no.4
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• pp.173-182
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• 1983

The influence of prazosin (0.1 mg/kg i.v.) on the excretion and diuretic action of furosemide (2mg/kg i.v.) in rabbits was studied to investigate an interaction between ${\alpha}-adrenergic$ blocking agent, prazosin and furosemide. The results were as follows; 1) With the combined administration of prazosin and furosemide, the plasma concentration of furosemide was increased, the urinary excretion rate and renal clearance of furosemide were reduced, and tile biological half-life of furosemide was increased. 2) The diuretic action of furosemide was significantly reduced with the combined administration of prazosin: maximal decrease in urine volume, urinary electrolytes, clearance of $Na^+$ and $Cl^-$, and GFR and RPF, as well as maximal increase in $Na^+$ reabsorption rate were noted 10 minutes after administration of furosemide (2mg/kg i.v.)

• Journal of Pharmaceutical Investigation
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• v.12 no.1
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• pp.12-22
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• 1982

The experimental study have showed that the Polygonatum officinale All. contains diosgenin and ${\beta}-sitosterol$ as active components. Even though many experimental studies were reported, still there are many unknown actions of components from the plant. The purpose of this study was to elucidate the mechanism of hypoglycemic action of ether extract of Polygonatum officinale. The hypoglycemic effect of the ether extract was tested in hyperglycemic rats induced experimentally, The effect on plasma free fatty acid and the acute toxicity were also examined by using mouse. The hypoglycemic effect of the ether extract was compared with other oral hypoglycemic agents such as chlorpropamide and buformin. The ether extract of Polyonatum officinale showed a marked hypoglycemic effect by 1 hour after oral administration in hyperglycemic rats and rabbits but the ethanol extract did not exhibit the hypoglycemic effect. The hypoglycemic effect of the ether extract was potentiated by chlorpropamide while buformin was weak.

• The Korean Journal of Pharmacology
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• v.30 no.1
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• pp.137-143
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• 1994

Enhancement or diminution of leukocyte migration to the specific site might be important factors for the development of inflammatory diseases. To investigate the effects of non-steroidal anti-inflammatory drugs (NSAIDs) on chemotaxis of neutrophil, we obtained neutrophils by Hypaque-Ficoll step gradient centrifugation and tested the effects of seven drugs on the n-formyl-leucyl-phenylalanine (FMLP)-induced migration of neutrophil using a 48-well micro chemotaxis assembly. Oxyphenbutazone, phenylbutazone, sulindac, zomepirac, and ibuprofen suppressed the migration of neutrophil at the therapeutic concentrations, however, indomethacin showed stimulation effect. IC50s for inhibition of neutrophil migration by these drugs are less than 100uM. When drugs were preincubated with FMLP, no inhibition on migration of neutrophil was observed. These results indicated that inhibitory effects of these drugs on migration of neutrophil might be related to the receptor sites of neutrophil rather than molecular inactivation of chemoattractant (FMLP). In conclusion, we suggested that the property of inhibition effects on neutrophil migration of several NSAIDs might be another mode of pharmacological action for anti-iflammatory effect, which showed significant effects at concentrations below therapeutic levels, in addition to cyclooxygenase inhibition.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.115-123
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• 2005

Historical changes of population abundances of European red mite (ERM), Panonychus ulmi (Koch), and two-spotted spider mite (TSSM), Tetranychus urticae (Koch) (Acari: Tetranychidae), were described in selected apple orchards in the National Horticultural Research Institute (NHRI, Suwon, Korea), based on research reports of the NHRI from 1958 to 1998. ERM was an abundant species up to 1970, and TSSM became a dominant species after 1980. The change occurred around mid 1970. Three hypotheses were made to explain the change: TSSM competitively replaces ERM, ground cover weeds are a major influencing factor on movement of TSSM (TSSM movement into trees is accelerated by destroying weeds), and ERM and TSSM populations are regulated by natural enemy complexes when the orchard system is not disrupted. And long-term results of the interaction between two species were projected according to the combination of different orchard management strategies: pesticide sprays (non-selective toxic pesticide spray : heavy pesticide pressure (HPP), and selective soft pesticide spray = low pesticide pressure (LPP)) and weed control methods (grass planting, and clean culture system with herbicides). In the HPP and grass planting system, ERMs are abundant because ERM can avoid competition with TSSM as movement of TSSM to trees are restricted, and natural enemy complexes are destroyed by toxic pesticides. In the HPP and clean culture system, TSSMs are abundant because TSSM moves to trees from early season and competitively replaces ERM. In the LPP and grass planting system, ERMs are abundant because movement of TSSM to trees is reduced, but they do not build up a high population density since their densities are regulated by natural enemy complexes. In the LPP and clean culture system, TSSM moves to trees and competes with ERM, but the competition pressure is reduced because population densities of mites are regulated in a lower level by natural enemy complexes. So, ERM can occurs in late season. Thus, two species can coexist temporarily with more ERM in early season and more TSSM in late season. TSSM abundant phenomenon presented in this study can be partially explained as a result of long-term interaction between ERM and TSSM under the HPP and clean culture system.

• Korean Journal of Weed Science
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• v.13 no.1
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• pp.14-18
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• 1993

Greenhouse study was undertaken to find tank-mix feasibility of quinclorac with molinate and propanil, selective post-emergence herbicides in controlling barnyardgrass, for reducing the application rate of quinclorac. Following foliar application in combination of quinclorac at 0.038, 0.075, 0.150, and 0.300kg ai/ha with molinate at 0.190, 0.380, 0.750 and 1.500kg ai/ha, and propanil at 0.263, 0.525, 1.050, and 2.100kg ai/ha at 3.5-leaf stage of barnyardgrass, fresh weight and weeding efficacy and their interaction by Colby's efficacy method were evaluated. Percent inhibition of barnyardgrass growth by quinclorac, molinate and propanil at recommended rate were 78.1, 26.1, and 61.7%, respectively. The dose combination shown above 85% in weeding efficacy were from 0.300kg of quinclorac with 0.75kg of molinate and 0.150kg of quinclorac with all rates of propanil. Therefore, combination of quinclorac with molinate tended to additive interaction and that of quinclorac with propanil appeared partially synergistic interaction. Conclusively, for reducing the application rate of quinclorac, the combination of quinclorac with propanil was more synergistic than that of quinclorac with molinate.

• Research in Plant Disease
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• v.25 no.2
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• pp.49-61
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• 2019

Plant viruses are among the important pathogens that cause severe crop losses. The most efficient method to control viral diseases is currently to use virus resistant crops. In order to develop the virus resistant crops, a detailed understanding of the molecular interactions between viral and host proteins is necessary. Recessive resistance to a pathogen can be conferred when plant genes essential in the life cycle of a pathogens are deficient, while dominant resistance is mediated by host resistance (R) genes specifically interacting with effector proteins of pathogens. Thus, recessive resistance usually works more stably and broadly than dominant resistance. While most of the recessive resistance genes have so far been identified by forward genetic approaches, recent advances in genome editing technologies including CRISPR/Cas9 have increased interest in using these technologies as reverse genetic tools to engineer plant genes to confer recessive resistance. This review summarizes currently identified recessive resistance genes and introduces reverse genetic approaches to identify host interacting partner proteins of viral proteins and to evaluate the identified genes as genetic resources of recessive resistance. We further discuss recent advances in various precise genome editing technologies and how to apply these technologies to engineer plant immunity.

• Journal of Pharmaceutical Investigation
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• v.18 no.3
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• pp.113-123
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• 1988

A series of water-soluble polyparacyclophanes bearing two diphenylmethane or two diphenyl ether skeletons were investigated to develop useful host compounds by using 1-anilinonaphthalene-6-sulfonate (ANS) and 2-p-toluidinylnaphthalene-6-sulfonate (TNS) as fluorescent hydrophobic substrates in aqueous solution. It was noteworthy that remarkable fluorescent enhancements and blue shifts of ANS and TNS were observed only in the presence of 1,6,20,25-tetraaza[6.1.6.1] paracyclophane (CPM 44) and 1,6,21,27-tetraaza [7.1.7.1] paracyclophane (CPM 55) for diphenylmethane skeleton, and 1,7,21,27-tetraaza-14,34-dioxa [7.1.7.1] paracyclophane (CPE 55) and 1,8,22,29-tetraaza-15,36-dioxa [8.1.8.1] paracyclophane (CPE 66) for diphenyl ether skeleton, comparing with ${\alpha}-\;and\;{\beta}-cyclodextrins$. However, their acyclic analogues such as 4,4'-dimethylaminodiphenylmethane and 4,4'-dimethylaminodiphenyl ether, and paracyclophanes whose cavities were smaller showed only small effects under the same conditions. These facts suggested that hosts and substrates were in an intimate contact which would not occur without larger structures, and thus that guest molecules were strongly incorporated in the hydrophobic cavities of these larger paracyclophanes. The effects of pH on the fluorescent intensity of ANS-CPM 44, ANS-CPM 55, ANS-CPE 55, ANS-CPE 66, TNS-CPM 44, TNS-CPM 55, TNS-CPE 55 and TNS-CPE 66 systems were not significant below pH 2.0, but their fluorescent intensities were markedly reduced with increasing ionic strength.

• Korean Journal of Weed Science
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• v.18 no.4
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• pp.286-294
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• 1998

This study was carried out to evaluate the interaction effect between molinate(S-ethyl N,N-hexamethylene-thiocarbamate) and simetryn(N,N'-diethyl-6-(methythio)-1,3,5-triazine-2,4-diamine) on weed bioefficacy and rice phytotoxicity in green house and paddy field. Combined application of molinate and simetryn showed synergistic herbicidal effect to Echinochloa crus-galli and additive herbicidal effect to Bidens tripartita, However, it showed synergistic phytotoxicity to rice. Combined application of molinate and simetryn reduced the flooding period desirable for controlling Echinochloa crus-galli by about 2~4days as compared to single application of molinate. It was concluded that the optimum combination of molinate and simetryn was 150g and 9g to 18g a.i./10a, respectively in viewpoint of bioefficacy and phytotoxicity.

• Applied Biological Chemistry
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• v.35 no.5
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• pp.367-374
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• 1992

This study was performed to investigate effects of probable detoxifying enzyme activity and toxicity by pesticides and their combinations in the fresh water fish. Seven pesticides including IBP, isoprothiolane, cartap, ridomil, chlorothalonil, captafol and endosulfan were subjected to investigate for their acute toxicites and synergism possibilities. The $LC_{50}$ value of endosulfan was the lowest at showing 0.0079 ppm and that of metalaxyl was the highest as showing 40 ppm over. The synergism effects of relative pesticides were observed in the combinations of isoprothiolane+IBP and isoprothiolane+cartap. The changes of glycogen contents in fish liver were assayed for 5 pesticides and its highest inhibition effect of glycogen showed in IBP treated fish. The activity of probable detoxifying enzymes including carboxylesterase (CE), glutathion S-transferase (GST) and lactate dehydrogenase (LDH) were assayed in carp liver at dose of sublethal concentrations. Effects of pesticides on changes in each enzyme activities were as follows: carboxylesterase (CE) activities were the highest in IBP and gtutathion S-transferase (GST) activities were the highest in iosoprothiolane+IBP. Both activities of carboxylesterase (CE) and glutahtion S-transferase (GST) were increased by 5 chemicals. The highest LDH activity showed in isoprothiolane treated fish, while the lowest activity was observed in isoprothiolane+cartap. Sublethal exposure to cartap and isoprothiolane+cartap in carp exerted various effects on LDH activity.

• Korean Journal of Weed Science
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• v.17 no.3
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• pp.288-294
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• 1997

Field and pot expeiments were carried out to evaluate the interaction between quinclorac and bensulfuron-methyl on growth of the rice plants(Oryza sativa L. cv. Choocheongbyeo) at 20, 45, 65 days-old stages. Quinclorac and bensulfuron-methyl showed antagonistic interaction at both stages, which were detected by the Chisaka's method at isobles of 10% growth inhibition. The antagonism indices were -0.63 and -1.67 at 20 and 65 days-old seedling stages, respectively. Leaf-rolling of rice occurred when quinclorac was applied at 600g ai/ha or more at 20 days-old seedling stage, while it occured at the dose of 900g ai/ha at 65 days-old stage. Bensulfuron-methyl reduced plant height and dry weight as well as tiller production at both stages. Leaf-rolling of rice was reduced when mixture of quinclorac and bensulfuron-methyl was applied due to antagonism of the two herbicides. High temperatures increased the phytotoxicity of bensulfuron-methyl, while the phytotoxicity caused by quinclorac alone was not responsive to temperature. The antagonistic effect between quinclorac and bensulfuron-methyl increased at low temperature as tested by the Colby's method.