• 한국식물병리학회지
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• 제14권6호
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• pp.654-660
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• 1998

Colletotrichum gloeosporioides and Glomerella cingulata are the most important pathogens causing anthracnose which may reduce the stand rate and yield on wide kinds of plants including strawberry. Average occurrence rate of anthracnose is 36.9% on major strawberry cropping areas in Korea. We newly found that C. gloeosporioides which does not forming a sexual stage, infects strawberry and differs in some characteristics concerning virulence, cultural and morphological properties to G. cingulata which has a sexual stage. C. gloeosporioides was mainly isolated from the crown with 35.2% rate, while G. cingulata was largely isolated from petiole, runner with 40.9% rate in infected strawberry plants. These two pathogens showed significant differences in cultural characteristics such as perfect stage formation, temperature response as well as benomyl resistance. It was demonstrated that C. gloeosporioides has significantly stronger pathogenicity than G. cingulata in pathogenicity test carried on strawberry plants to various strawberry cultivars. Akihime, Akaneko and Nyoho forcing cultured strawberry cultivars, considered to be susceptible, while semiforcing cultured cultivars, such as Suhong and Holowase, were shown resistant to both pathogens. In non-wound inoculation, C. gloeosporioides was shown pathogenicity on the apple fruit, but G. cingulata could not infect it.

• 동의생리병리학회지
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• 제29권6호
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• pp.485-491
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• 2015

This study was aimed to investigate the relaxation effects of Eucomiae Cortex (EC) extract in isolated rabbit corpus cavernosum smooth muscle and its mechanism. To evaluate the relaxation of EC extract in rabbit corpus cavernosum, EC extract was treated in corporal strips which were precontracted with phenylephrine(PE). To study its mechanism, Nω-nitro-L-arginine (L-NNA) was pretreated after infuse of EC extract and compared with non-treated. In calcium chloride (Ca²⁺) -free krebs solution, EC extract and Ca²⁺ 1 mM were infused by turns after Ca²⁺ 1 mM was treated into corporal strips contracted by PE. Cell ability, nitric oxide (NO) and epithelial nitric oxide synthase (eNOS) on human umbilical vein endothelial cell (HUVEC) were measured by MTT assay, Griess reagent system and histochemical, immunohistochemical methods. EC extract showed a significant relaxation effects on the corporal strips, this effects were inhibited by pretreatment of L-NNA. EC extract inhibited the increase of contraction by Ca²⁺ influx in Ca²⁺-free krebs solution, and eNOS positive reaction in corpus cavernosum, NO production in HUVEC increased by treatment of EC extract. These result suggest that the relaxation effects of EC extract in isolated corpus cavernosum smooth muscle are involved in increase of eNOS and NO production, blocking of extracellular Ca²⁺ influx.

• 한국동물위생학회지
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• 제32권2호
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• pp.155-163
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• 2009

Fowl typhoid (FT) is a septicemic disease caused by Salmonella Gallinarum. The purpose of this study was to investigate the antimicrobial resistance and pulsed-field gel electrophoresis (PFGE) patterns of S. Gallinarum isolated from chicken. During 1999 to 2004, there was isolated a total of 100 strains in liver and spleen. The biochemical characteristics of S. Gallinarum isolates was nonmotile, no production of H$_2$S, glucose gas, non-fermented rhamnose, indole-negative, fermentation of dulcitol, mannitol, maltose, and ornithine decarboxylase. At antimicrobial susceptibility, all of isolates were susceptible to amoxicillin/clavulanic acid, amikacin, neomycin, kanamycin, norfloxacin and enrofloxacin. One hundred isolates were divided into 54 resistant patterns and 37 strains was 6-multi drug resistance. PFGE of Xba I restriction fragments of S. Gallinarum isolates was 20 patterns.

• Journal of Species Research
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• 제9권4호
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• pp.339-345
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• 2020

The Earth contains billions of microbial species, although the vast majority cannot be cultured in laboratories and are thus considered unidentified and uncharacterized. Extremophiles are microorganisms that thrive in extreme conditions, including temperature, salinity, and pH. Extremophilic microorganisms have provided important insights for biological, metabolic, and evolutionary studies. Between 2017 and 2019, as part of a comprehensive investigation to identify bacterial species in Korea, eight bacterial strains were isolated from marine and non-marine environments in Jeju Island. These strains were cultured under extreme salinity or pH conditions. Phylogenetic analysis using 16S ribosomal RNA(rRNA) gene sequencing indicated that all eight strains belonged to the phyla Gammaproteobacteria, Bacilli, and Alphaproteobacteria. Based on their high 16S rRNA gene sequence similarities(>98.7%) and the formation of strong monophyletic clades with their closest related species, all isolated strains were considered as an unrecorded strain, previously unidentified species. Gram stain reaction, culture conditions, colony and cell morphology, biochemical characteristics, isolation source, and National Institute of Biological Resources(NIBR) IDs are described in this article. The characterization of these unrecorded strains provides information on microorganisms living in Korea.

• 한국동물위생학회지
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• 제30권3호
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• pp.363-374
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• 2007

A biochemical characterization and antimicrobial drugs susceptibility study was conducted in four breeding kennel which was canine abortion caused by Brucella canis in Gyeongbuk province in 2003-2006. Total of 267 dogs domesticated in the four kennel were examination. Among them, 143 (53.6%) dogs were sero-positive and 25 of blood samples were isolated to Brucella canis. At amplification of 35KDa-BCSP gene using PCR, 711 bp DNA fragment was same visible in 25 isolates and B canis RM6/66. Biochemical characterization of B canis isolated was non-hemolytic, no production of $H_2S$, no fermentation of carbohydrates, catalase-positive, oxidase-positive, indol-negative, hydrolyzation of urea, reduction of nitrate and development of thionin dye medium. Using disk-diffusion method, all of 25 strains tested were found to be highly susceptible to tetracycline, aminoglycoside, quinolone, macrolide antibiotics, rifampin and ampicillin in vitro. Using PFGE with restriction enzyme Smi I, 25 isolates tested were typed to 2 pattern, S1 and S2.

• Archives of Pharmacal Research
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• 제19권5호
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• pp.423-428
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• 1996

Optimum conditions for hydrolysis were investigated to enhance water-solubilities of protein-bound polysaccharides in the basidiocarps of Ganoderma lucidum by treating chymotrypsin. We also attempted with Ganoderma lucidum residue remaining after extracting hot water-soluble compoents in Ganoderma lucidum. After hydrolyzing under optimum conditions (20 ppm chymotrypsin, 2% Gampderma lucidum or 6% Ganoderma lucidum residue, at pH 10 and at $ 40^{\circ}C$), the amounts of total protein and carbohydrate of hydrolysate were measured. Michaelis constant, $K_{m}$, and maximum rate, $V_{max}$, calculated by Lineweaver-Buck plot for the hydrolysis of Ganoderma lucidum were 1.73% and 0.073%/min respectively and those for hydrolysis of Ganoderma lucidum residue were 2.40% and 0.033%/min respectively. The amount of polysaccharide isolated from Ganoderma lucidum (100 g) treated with chymotrypsin was only 3.07 g, but significantly increased amount (14.34 g) of polysaccharides was isolated from Ganoderma lucidum residue (100 g) treated with chymotrypsin. The protein-bound polysaccharide was isolated from the non-hydrolyzed and hydrolyzed sample and molecular weights of the polysaccharide were measured by Sepharose CL-48 gel filtration.

• 한국동물위생학회지
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• 제34권3호
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• pp.209-216
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• 2011

This study carried out to investigate the pathogenic Streptococcus spp. isolated from respiratory tract of Thoroughbred in Jeju province. The specimens were collected from nasal mucosa using a culture swab from 113 Thoroughbred horses. Suspected colonies were selected onto blood and MacConkey agar plate, and identified by standard biochemical properties using Vitek 2 system and PCR method. In this study, we isolated S. equi (n=6), S. zooepidemicus (n=31), S. equisimilis (n=5), S. dysgalactiae (n=2), S. agalctiae (n=1), non identified ${\beta}$-hemolytic Streptococcus spp. (n=1) from Thoroughbred horses. In antimicrobial susceptibility test, it showed a high sensibility in the most of antimicrobial except for neomycin, streptomycin, spectinomycin, erythromycin and clindamycin. These results will provide the basic information to establish control measures for the treatment and prevention of respiratory disease by pathogenic Streptococcus spp. in Thoroughbred horses in Korea.

• 한국환경과학회지
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• 제14권7호
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• pp.649-655
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• 2005

Microcystis aeruginosa is common form of cyanobacteria (blue-green algae) capable of producing toxic heptapeptide (microcystin) that cause illness or death. The comparison of molecular genetic method with the morphological characteristics of cyanobacteria was conducted. We have designed PCR primers (JJM98F, JJM1141R) for cyanobacterial 16S rRNA and phycocyanin intergenic spacer (PC-IGS) gene domain. To confirm the production of microcystins, PCR primers for the N-methyltransferase (NMT) domain of microcystin synthetase gene mcyA were designed using 21 cyanobacteria strains Most of isolated strains from the Nakdong River was classified as Microcystis aeruginosa and the similarities were $99\%$ with M. aeruginosa AF 139292. $38.1\%$ of isolated strains contained microcystin synthesis gene. NMT (N-methyltransferase) were not detected in isolated strain in several strains, which means non-toxic. However, the NMTs of the strains were detected during the cultivation.

• Geomechanics and Engineering
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• 제7권1호
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• pp.87-103
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• 2014

This study investigated the effect of soil-structure interaction (SSI) on the response of base-isolated buildings. Seismic isolation can significantly reduce the induced seismic loads on a relatively stiff building by introducing flexibility at its base and avoiding resonance with the predominant frequencies of common earthquakes. To provide a better understanding of the movement behavior of multi-story structures during earthquakes, this study analyzed the dynamic behavior of multi-story structures with high damping rubber bearing (HDRB) behavior base isolation systems that were built on soft soil. Various models were developed, both with and without consideration of SSI. Both the superstructure and soil were modeled linearly, but HDRB was modeled non-linearly. The behavior of the specified models under dynamic loads was analyzed using SAP2000 computer software. Erzincan, Marmara and Duzce Earthquakes were chosen as the ground motions. Following the analysis, the displacements, base shear forces, top story accelerations, base level accelerations, periods and maximum internal forces were compared in isolated and fixed-base structures with and without SSI. The results indicate that soil-structure interaction is an important factor (in terms of earthquakes) to consider in the selection of an appropriate isolator for base-isolated structures on soft soils.

• Advances in Traditional Medicine
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• 제3권3호
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• pp.151-156
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• 2003

The leaves of Mirabilis jalapa L contains protein fraction presumed ribosome-inactivating protein (RIP). RIP is a group of protein that has RNA N-glycosidase activity that is capable to inhibit protein synthesis. Protein fraction of the plant was shown to be cytotoxic on HeLa cell-line, however, the mechanism by which the protein kill the cells is not identified yet, whether trough apoptosis, necrosis, or other mechanism. This research aim to study the mechanism of cell death caused by the protein fraction isolated from the leaves of this plant on HeLa and Raji cell-line, as representative of different kind of cancer cells. Results showed that protein fraction isolated from the leaves of Mirabilis jalapa L was more cytotoxic to HeLa cell-line (LC50: 0.65 mg/ml) than to Raji cell-line (1.815 mg/ml) on 48 hours incubation time. Moreover, it was demonstrated that the death of HeLa cells caused by the protein fraction was due to induction of apoptosis, while on Raji cell-line was due to non-apoptosis way, presumably via necrosis.