• 대한수의학회지
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• 제61권2호
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• pp.13.1-13.8
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• 2021

Mammalian reovirus (MRV) causes respiratory and intestinal disease in mammals. Although MRV isolates have been reported to circulate in several animals, there are no reports on Korean MRV isolates from wildlife. We investigated the biological and molecular characteristics of Korean MRV isolates based on the nucleotide sequence of the segment 1 gene. In total, 144 swabs from wild animals were prepared for virus isolation. Based on virus isolation with specific cytopathic effects, indirect fluorescence assays, electron microscopy, and reverse transcription-polymerase chain reaction, only one isolate was confirmed to be MRV from a Korean roe deer (Capreolus pygargus). The isolate exhibited a hemagglutination activity level of 16 units with pig erythrocytes and had a maximum viral titer of 10^5.7 50% tissue culture infectious dose (TCID₅₀)/mL in Vero cells at 5 days after inoculation. The nucleotide and amino-acid sequences of the partial segment S1 of the MReo2045 isolate were determined and compared with those of other MRV strains. The MReo2045 isolate had nucleotide sequences similar to MRV-3 and was most similar (96.1%) to the T3/Bat/Germany/342/08 strain, which was isolated in Germany in 2008. The MReo2045 isolate will be useful as an antigen for sero-epidemiological studies and developing diagnostic tools.

• Structural Engineering and Mechanics
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• 제88권3호
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• pp.221-238
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• 2023

This paper developed and examined a novel passive vibration isolator (i.e., "X-inerter") motivated by combining a bio-inspired structure and a rack-pinion inerter. The bio-inspired structure provided nonlinear stiffness and damping owing to its geometric nonlinearity. In addition, the behavior was further enhanced by a gear inerter that produced a special nonlinear inertia effect; thus, an X-inerter was developed. As a result, the X-inerter can achieve both high-static-low-dynamic stiffness (HSLDS) and quasi-zero stiffness (QZS), obtaining ultra-low frequency isolation. Furthermore, the installed inerter can produce a coupled nonlinear inertia and damping effect, leading to an anti-resonance frequency near the resonance, wide isolation region, and low resonance peak. Both static and dynamic analyses of the proposed isolator were conducted and the structural parameters' influence was comprehensively investigated. The X-inerter was proven to be comparatively more stable in the ultra-low frequency than the benchmarking QZS isolator due to the nonlinear damping and inertia properties. Moreover, the inertia effect could suppress the bio-inspired structure's super- and sub-harmonic resonance. Therefore, the X-inerter isolator generally possesses desirable nonlinear stiffness, nonlinear damping, and unique nonlinear inertia, designed to achieve the ultra-low natural frequency, the anti-resonance property, and a wide isolation region with a low resonance peak.

• IMMUNE NETWORK
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• 제4권1호
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• pp.7-15
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• 2004

Background: The heat shock proteins (HSPs) play an important role in cellular protection mechanisms against physical or chemical stresses. In this study scFv antibodies specific for human HSP70.1 were isolated from a semi-synthetic human scFv library with the ultimate goal of developing anti-HSP70.1 intracellular antibody (intrabody) that may offer an attractive alternative to gene targeting to study the function of the protein in cells. Methods: A semi-synthetic human scFv display library ($5{\times}10^{8}$ size) was constructed using pCANTAB-5E vector and the selection of the library against bacterially expressed recombinant human HSP70.1 was attempted by panning. Results: Three positive clones specific for recombinant HSP70.1 were identified. All three clones used $V_{H}$ subgroup III. On the other hand, $V_{L}$ of two clones belonged to the kappa light chain subgroup I, but the other utilized $V_{k}$ subgroup IV Interestingly, these scFv molecules specifically reacted to the recombinant HSP70.1, yet failed to recognize native HSP70 induced in U937 human monocytic cells by heat treatment. Conclusion: Our results indicated that affinity selection of an scFv phage display library using recombinant antigens produced in E. coli might not guarantee the isolation of scFv antibody molecules specific for a native form of the antigen. Therefore, the source of target antigens needs to be chosen carefully in order to isolate biofunctional antibody molecules.

• ALGAE
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• 제26권4호
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• pp.343-350
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• 2011

Fermentation and enzyme-assisted extraction (EAE) improve nutritional and functional properties of foods by increasing the extraction of active compounds, ingestion rates, and body absorption. In this study, we investigated whether applying the EAE process improves the extraction and isolation efficiency of a polysaccharide from fermented Ecklonia cava (FE), which inhibited NO production in lipopolysaccharide (LPS)-activated RAW 264.7 cells. The results showed that the FE using the fungi Candida utilis and two different bacteria, namely Lactobacillus brevis and Saccharomyces cerevisiae increased protein and carbohydrate contents in comparison with those in non-fermented E. cava (NE). Aqueous extracts of fermented E. cava increased extraction yields and carbohydrate content, compared with the aqueous extract of NE. In addition, treating LPS-stimulated RAW 264.7 cells with aqueous extracts resulted in reduced NO production compared to that in LPS-treated cells. Ten EAEs of L. brevis-fermented E. cava (LFE) improved NO inhibitory effects in LPS-activated RAW 264.7 cells and the Viscozyme extract (VLFE) from the resulting extracts showed the highest NO inhibitory effect. We found that the >30 kDa fraction of VLFE led to markedly high inhibition of LPS-induced NO production as compared to that in the <30 kDa fraction. The crude polysaccharide isolated from >30 kDa fraction (VLFEP) consisted of fucose and markedly decreased NO production induced by LPS stimulation. VLFEP could be useful as an anti-inflammatory agent to suppress macrophage activation.

• Archives of Pharmacal Research
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• 제25권6호
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• pp.856-859
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• 2002

In the course of finding Korean natural products for acetylcholinesterase (AChE) inhibitory activity, we found that a methanolic extract of the roots of Angelica dahurica showed significant inhibitory effects on AChE. Bioassay-guided fractionation of the methanolic extract resulted in the isolation of three furanocoumarins, isoimperatorin (1), imperatorin (2) and oxypeucedanin (3), as active principles. These compounds inhibited AChE activity in a dosedependent manner, and the $IC_{50}$ values of compounds 1-3 were 74.6, 63.7 and 89.1 uM, respectively.

• Bulletin of the Korean Chemical Society
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• 제32권11호
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• pp.3887-3892
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• 2011

An efficient synthesis of 1,5-Benzothiazepines via Michael addition of corresponding (E)-1-(2-hydroxyphenyl)-3-(4-(phenylthio)phenyl)prop-2-en-1-one is described under ultrasound irradiation. A series of novel 2-((E)-2,3-dihydro-2-(4-(phenylthio)phenyl)benzo[b][1,4]thiazepin-4-yl)phenol derivatives was confirmed on the basis of $^1H$ NMR, Mass, IR spectral data and Elemental analysis. The synthesized compounds were evaluated for their antimicrobial activities. Most of the compounds were found to be comparable potent than the reference standard drugs. Utilization of ultrasound irradiation, simple reaction conditions, isolation, and purification makes this manipulation very interesting from an economic and environmental perspective.

• 한국식품영양학회지
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• 제11권4호
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• pp.416-419
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• 1998

Identification of escherchia coli K1 polysaccharide antigen isolated from urine specimens of urinary tract infections in children were performed from of 1992 to 1993 in Kyoto, Japan. The serotypes of E. coli were categorized that O1:H7, O2:H6, O2:H7, O16:H6, O18:H7, O18:H￣, and O135:H44 among 14 strains isolated from urine specimens of urinary tract infections in children by the serological test. And, one strain (O18:H￣, isolation rate: 7.1%) of E. coli K1 polysaccharide antigen among 14 strains were isolated from urine specimens of urinary tract infections in children by the bacteriophage test.

• Ocean and Polar Research
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• 제39권1호
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• pp.45-49
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• 2017

During the search for anticholinesterase compounds from marine organisms, we were able to isolate 6,6'-bieckol from a red alga, Grateloupia elliptica. This compound showed moderate acetylcholinesterase (AChE) inhibitory activity in a micromole range ($IC_{50}$ $44.5{\mu}M$). However, for butyrylcholinesterase (BuChE), a new target for the treatment of Alzheimer's disease (AD), it showed particularly potent inhibitory activity ($IC_{50}$ $27.4{\mu}M$), which is more potent compared to AChE. It also inhibits BACE-1, a new target for reducing the generation of ${\beta}-amyloid$.

• 한국식품영양과학회지
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• 제28권5호
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• pp.1003-1009
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• 1999

For the isolation of probiotics which may be used for the human beings and animals, we have screened the microorganisms from chicken intestines which have acid and bile tolerance and the growth inhibition of pathogenic E. coli and Salmonella typhimurium. Among them, a strain which was identified as Lactobacillus salivarius had around 66% of survival after 2h incubation in the artificial gastric juice and 9% of survival after 24h incubation in the presence of 0.3% bile salts, and showed complete inhibition against both path ogenic E. coli and Salmonella typhimurium after 24 h coincubation. Its storage stability after lyophilization could be improved by adding polyvinylpyrrolidone.

• Natural Product Sciences
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• 제23권4호
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• pp.253-257
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• 2017

The phytochemical study for the extract of Nelumbo nucifera (Nymphaceae) seeds has led to the isolation of ten compounds including five simple phenolic compounds, two indole derivatives, a flavonoid glycoside, two abscisic acid derivatives. The interpretation of 1D and 2D NMR and ESI-Q-TOF-MS spectroscopic data revealed the chemical structures of isolates to be p-hydroxybenzoic acid (1), protocatechuic acid (2), (E)-p-coumaric acid (3), (E)-ferulic acid (4), (E)-sinapate-4-O-${\beta}$-$\text\tiny{D}$-glucopyranoside (5), tryptophan (6), 3-indoleacetic acid (7), isoschaftoside (8), dihydrophaseic acid (9), dihydrophaseic acid 3'-O-${\beta}$-$\text\tiny{D}$-glucopyranoside (10). To the best of our knowledge, 1 - 5 and 7 were identified for the first time from N. nucifera seeds, and the presence of dihydrophaseic acid (9) and its glucoside (10) were demonstrated secondly in this plant.