• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.266-266
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• 2006

The cell spheroid (multicellular mass) is enhanced cell functions because of the cell-cell interaction compared with the individual cell. The objective of this study is synthesis, characterization and evaluation of novel crosslinkers to form spheroid in a short time. Our approach to bridge cells is based on the crosslinking of the cell membrane via the hydrophobic interaction. The crosslinker was prepared by the reaction between ethylenediamine and poly(ethylene glycol) (PEG) derivative with oleyl group as hydrophobic group at the terminal group. The product was characterized with gel permeation chromatography (GPC) and FT-IR. Furthermore, cell culture experiment was also performed to confirm spheroid formation. The function of prepared spheroids was evaluated.

• Journal of Microbiology
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• 제41권2호
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• pp.137-143
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• 2003

The present study was performed to identify pathogenic factors of Chlamydia trachomatis, which invade the host cell membrane. We prepared monoclonal antibody against C. trachomatis and searched for pathogenic factors using this antibody, and subsequently identified the surface components of the elementary body of C. trachomatis, i.e., major outer membrane protein (MOMP), lipopolysaccharide (LPS), and two other surface exposure proteins. These proteins are believed to be important in the pathogenesis of host cell chlamydial infection. Additionally, to identify factors related to the host cell and C. trachomatis, we prepared C. trachomatis infected and non-infected McCoy cell extracts, and reacted these with anti-chlamydial LPS monoclonal antibody. We found that anti-chlamydial LPS monoclonal antibody reacted with a 116 kDa proteinaceous McCoy cell membrane component.

• 한국미생물·생명공학회지
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• 제23권3호
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• pp.249-254
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• 1995

When mating type A and a cells of heterobasidiomycetous yeast Rhodosporidium toruloides were mix-cultured, both of the mating type cells have shown strong agglutination. But this agglutination was not detactable when the A and a cell were cultured separately. From reagglutination made just after the result of disassembling the agglutination by sonication, we knew that the agglutination was sexual-agglutination, not simple physical cell agglutination. The sexual agglutination was progressed actively on logarithmic phase and, in addition, progressed faster on mating type a cell treated with rhodotorucine A. These sexual agglutination have been inhibited by several protease such as trypsin, pronase, chymotrpysin and thermolysin and inhibited by 5 mM DTT as well.

• Reproductive and Developmental Biology
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• 제35권1호
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• pp.1-8
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• 2011

Techniques to evaluate gene expression profiling, such as sufficiently sensitive cDNA microarrays or real-time quantitative PCR, are efficient methods for monitoring human pluripotent stem cell (hESC/iPSC) cultures. However, most of these high-throughput tests have a limited use due to high cost, extended turn-around time, and the involvement of highly specialized technical expertise. Hence, there is an urgency of rapid, cost-effective, robust, yet sensitive method development for routine screening of hESCs/hiPSCs. A critical requirement in hESC/hiPSC cultures is to maintain a uniform undifferentiated state and to determine their differentiation capacity by showing the expression of gene markers representing all three germ layers, including ectoderm, mesoderm, and endoderm. To quantify the modulation of gene expression in hESCs/hiPSC during their propagation, expansion, and differentiation via embryoid body (EB) formation, we developed a simple, rapid, inexpensive, and definitive multimarker, semiquantitative multiplex RT-PCR platform technology. Among the 9 gene primers tested, 5 were pluripotent markers comprising set 1, and 3 lineage-specific markers were combined as set 2, respectively. We found that these 2 sets were not only effective in determining the relative differentiation in hESCs/hiPSCs, but were easily reproducible. In this study, we used the hES/hiPS cell lines to standardize the technique. This multiplex RT-PCR assay is flexible and, by selecting appropriate reporter genes, can be designed for characterization of different hESC/hiPSC lines during routine maintenance and directed differentiation.

• Journal of Microbiology and Biotechnology
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• 제29권11호
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• pp.1806-1816
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• 2019

Candida albicans is an opportunistic fungus possessing multiple virulence factors controlling pathogenicity. Cell wall proteins are the most important among these factors, being the first elements contacting the host. Ddr48 is a cell wall protein consisting of 212 amino acids. A DDR48 haploinsufficient mutant strain was previously found necessary for proper oxidative stress response and drug resistance. In this study, we aimed to further elucidate the role of Ddr48 by performing additional phenotypic characterization assays. A combinatory proteomic and bioinformatics approach was also undertaken to determine differentially expressed cell wall proteins. Results showed that the mutant strain exhibited a 10% decrease in adhesion mirrored by a 20% decrease in biofilm formation, and slight sensitivity to menadione, diamide, and SDS. Both strains showed similar hyphae formation, virulence, temperature tolerance, and calcofluor white and Congo red sensitivities. Furthermore, a total of 8 and 10 proteins were identified exclusively in the wild-type strain grown under filamentous and non-filamentous conditions respectively. Results included proteins responsible for superoxide stress resistance (Sod4 and Sod6), adhesion (Als3, Hyr4, Pmt1, and Utr2), biofilm formation (Hsp90, Ece1, Rim9, Ipp1, and Pra1) and cell wall integrity (Utr2 and Pga4). The lack of detection of these proteins in the mutant strain correlates with the observed phenotypes.

• Journal of Periodontal and Implant Science
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• 제32권2호
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• pp.351-360
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• 2002

In the study presented here, identification, purification, and partial characterization of a hemin-regulated protein in Prevotella nigrescens were carried out. The results of this study confirm that the availability of hemin influences the expression of a selected membrane protein as well as the growth rate of P. nigrescens ATCC 33563. The 50 kDa cell envelope associated protein, whose expression is hemin regulated, is considered to be a putative hemin-binding protein from P. nigrescens. Disulfide bonds were not present in this protein, and N'-terminal amino acid sequence analysis revealed that this protein belongs to a new, so far undescribed protein. The 50 kDa protein was found to be rich in hydrophilic amino acids, with glycine comprising approximately 60% of the total amino acids. The study described here is the first to identify, purify, and biochemically characterize a putative hemin-binding protein from P. nigrescens. Work is in progress to further characterize the molecular structure of this protein.

• Advances in nano research
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• 제11권6호
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• pp.657-665
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• 2021

The present work aimed to explore green approach via aqueous leaves extract of Murraya koenigii (ALEMk) for the synthesis of silver nanoparticles (AgNPsMk) in single step. The synthesis process was visualized with a color change and monitored by employing UV/Visible spectroscopy and a clear peak attained at 420 nm confirming the synthesis of AgNPsMk. The possible functional groups present in the extract which participated in the synthesis of AgNPsMk were identified with the help of FTIR spectroscopy. Further characterization using TEM images revealed the spherical shape of AgNPsMk with average particle size of 20 nm displaying well dispersion throughout the solution. Pronounced antioxidant activities of AgNPsMk at increased concentrations observed which evidencing strong radical scavenging ability. Moreover, AgNPsMk exhibited strong antibacterial behavior when tested against bacterial strains of Escherichia coli and Bacillus subtilis. Moving ahead, in vitro cytotoxicity work revealed potent cell viability loss appearing in AU565 and HeLa cancer cell lines on exposure to AgNPsMk at increased concentration. Finally, in vivo assessment carried out inside male Wistar rats indicated non toxic effect on examined liver tissues besides biochemical analysis including bilirubin, alkaline phosphtase (ALP) and serum glutamate pyruvate transaminase (SGPT) which found within the normal range when compared with control. The prior research work profoundly apprises the potential of green synthesized AgNPsMk to play a significant role in biomedical applications and formulations.

• 대한수의학회지
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• 제32권2호
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• pp.245-250
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• 1992

This study was performed to demonstrate the presence of large granular lymphocyte(LGL) in Sprague-Dawley(SD) rats and morphologically observe NK cell and also establish the method of isolation of natural killer cell in SD rats. By percoll discontinuous density gradients centrifugation, highly enriched LGL population were shown to fraction 2(border line between 44.2% and 50.8%). LGL were shown to bind selectively to YAC1 mouse lymphoma cell. This fraction expressed very high NK cell cytolysis. Therefore, we thought that LGL have NK activity in SD rats. The Morphology of rat LGL is very similar to that of human LGL. These cells have an eccentric kidney-shaped nucleus. Their most distinctive feature was their cytoplasmic azurophilic granules. Another distinguishing feature of rat LGL was their high cytoplasmic : nuclear ratio. It was concluded that LGL played a role part in mediating natural killer activity in this species.

• 약학회지
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• 제38권6호
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• pp.715-720
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• 1994

${\alpha}2-macroglobulin$ $({\alpha}2-M)$ has been shown to have a variety of activities. One of those activities is the suppression of immune response. Characterization of the immunosuppressive factor secreted by a T cell hybridoma showed that ${\alpha}2-M$ was produced and secreted from the T cell hybridoma. ${\alpha}2-M$ was produced abundantly from the T cell hybridoma when cultured as ascites. The isolation and identification of the ${\alpha}2-M$ were studied using affinity chromatography and N-terminal amino acid sequencing. The extended observations were that the ${\alpha}2-M$ produced by the T cell hybridoma suppresses mixed lymphocyte reaction.

• Animal cells and systems
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• 제15권3호
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• pp.197-202
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• 2011

The present study demonstrates the first-ever characterization of cell types that express the vanilloid receptor 1 (VR1) in the taste buds of rat circumvallate papillae. We performed electron microscopy to identify the subcellular location. The VR1 immunoreactivity was associated with the endoplasmic reticulum, cytoplasmic vesicles, and plasma membrane of taste cells. These results demonstrate the localization of the VR1 in membranous structures of the taste cells. We used double immunofluorescence histochemistry with taste cell type-specific markers to identify the cell types that express the VR1. The VR1 was detected in all functional taste cell types (Type I, Type II, and Type III cells). Together, our data suggest that the VR1 might play different roles according to the cell types within a taste bud.