• Bulletin of the Korean Chemical Society
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• 제26권6호
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• pp.913-915
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• 2005

The three new lignans 1-3 were isolated from the methanol extracts of the flower buds of Magnolia fargesii. They were elucidated as (7S,8R)-1-(3,4-dimethoxyphenyl)-2-O-(2-methoxy-4-omegahydroxypropylphenyl) propane-1,3-diol, (7S,8S)-1-(4-hydroxy-3-methoxyphenyl)-2-O-(6-hydroxy-2-methoxy-4-omegahydroxypropylphenyl) propane-1,3-diol, and [tetrahydro-4-hydroxy-2-(3,4,5-trimethoxyphenyl)furan-3-yl]methyl 3,4-dimethoxy benzoate by spectral analysis.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.361-361
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• 2010

The separated quasi-one-dimensional ($7{\times}7$) and ($5{\times}5$) phases on vicinal Si(557) surfaces were successfully realized by changing the crystallographic orientation and thermal treatment conditions. A small change in the crystallographic orientation of the Si(557) surface stabilized the quasi-one-dimensional ($5{\times}5$) phase of a (111) facet on vicinal Si(557) surfaces and made it coexist with a quasi-one-dimensional ($7{\times}7$) phase after an optimal thermal treatment, whereas only the quasi-one-dimensional ($7{\times}7$) phase was stable on the Si(557) surface. Interestingly, this causes the (111) terraces with different widths (L) to prefer only one of the $5{\times}5$ (L=12) and $7{\times}7$ (L=9) phases resulting in long-range order of both phases along the step edge direction, which was observed by scanning tunneling microscopy (STM) and was supported by first principle calculations. In contrast, the quasi-one-dimensional ($5{\times}5$ and ($7{\times}7$) phases were arranged randomly across the step edge direction. The change of surface morphology of vicinal Si(557) surfaces will be discussed with STM images and theoretical calculations by changing crystallographic cutting angles and thermal treatment conditions.

• Molecules and Cells
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• 제25권2호
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• pp.305-311
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• 2008

After successful clinical application, arginine deiminase (ADI) has been proposed to be a new cancer therapeutic. In the present study, we examined the effect of ADI in combination with ionizing radiation (IR) on MCF-7 cell growth and clonogenic cell death. Cell growth was inhibited by IR in a dose-dependent manner and ADI enhanced the radiosensitivity. ADI itself did not suppress the growth of MCF-7 cells due to the high level of expression of argininosuccinate synthetase (ASS), which convert citrulline, a product of arginine degradation by ADI, to arginine. Previously, it was suggested that ammonia, another product of arginine degradation by ADI, is the main cause of the growth inhibition of irradiated hepatoma cells contaminated with ADI-expressing mycoplasma [van Rijn et al. (2003)]. However, we found that ammonia is not the only factor that enhances radiosensitivity, as enhancement was also observed in the absence of ammonia. In order to identify the enhancing effect, levels of ASS and proteins related to the cell cycle were examined. ASS was unchanged by ADI plus IR, but p21 (a CDK inhibitor) was upregulated and c-Myc downregulated. These findings indicate that changes in the expressions of cell cycle proteins are involved in the enhancement of radiosensitivity by ADI. We suggest that ADI is a potential adjunct to cancer therapy.

• Bulletin of the Korean Chemical Society
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• 제27권2호
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• pp.243-250
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• 2006

Three novel potential metal ion chelating units have been synthesized and characterized: 5-hexylcarbamoyl-3,4-dihydroxythiophene-2-carboxylic acid methyl ester (5), 3-benzyloxy-4-hydroxythiophene-2,5-dicarboxylic acid bis-hexylamide (6), and 3,4-dihydroxythiophene-2,5-dicarboxylic acid bis-hexylamide (7). The crystal structure of 6 was obtained and suggests the presence of three distinct intramolecular hydrogen bonds, namely $[N_{amide}-H{\cdot}{\cdot}{\cdot}O]$ $[O-H{\cdot}{\cdot}{\cdot}O_{amide}]$ and $[N_{amide}-H{\cdot}{\cdot}{\cdot}S]$. Boron chelation with 5, 6 and 7 through the use of $BF_3, \;B(OH)_3 \;or \;B(OMe)_3$ was probed by $^1H$, $^{11}B$, and $^{13}C$ NMR spectroscopy. Technetium (I) chelation with 5, 6 and 7 was also studied via HPLC elutions using $[^{99m}Tc(CO)_3(OH_2)_3]^+$.

• 대한수의학회지
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• 제51권2호
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• pp.129-137
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• 2011

Swine diseases could be caused by unrecognized or minor pathogens. In this study, two unknown cytopathogenic agents were isolated from swine, through cell culture. In order to identify these two cytopathogenic agent (designated CP129 and #2045-7), a particle associated nucleic acids PCR (PANPCR) from previous paper was used with simple modification. The cloning procedure was more specified in this study by adding cell control system. According to the modified PAN-PCR, two and four agentsspecific DNA sequences were obtained from CP129 and #2045-7, respectively, and they were identified as Mycoplasma (M.) hyorhinis and Mammalian orthoreovirus by nucleotide BLAST. Since M. hyorhinis (CP129) was filterable and non-visible by microscope, this unusual virus-like nature of M. hyorhinis (CP129) was discussed. Especially, the reovirus (#2045-7) was a serotype 3 and a triple reassortant among three serotypes of reoviruses. It was grouped with recently reported reoviruses from disease cases (swine, human and feline), based on the genetic analysis of L1 and S1 partial sequences. In conclusion, two unknown cytopathogenic agents were successfully identified using modified PAN-PCR with cell control system and they were characterized in this study.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.395-401
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• 2008

Since metallic foam will increase the performance of heat exchanger, it have caused many researcher's attention recently. Our research base on the model that metallic foams applied to heat exchanger. In this case, there is three kind of heat transfer mechanisms, heat conduction in fibers, heat transfer by conduction in fluid phase, and internal heat change between solid and fluid phases. In this paper we study both the hydraulic and thermal aspect performance. Pressure drop along air flow direction will be presented. As thermal aspect, we first discuss the acceptance of applying thermal equilibrium among the two phases. then to calculate the dimensionless temperature profile, the heat transfer coefficient and Nu number in 14 metallic foams(7 Aluminium foams, 7 FeCrAlY foams). All these discussion is based on the same velocity u=2 m/s.

• Journal of Microbiology and Biotechnology
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• 제28권12호
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• pp.2029-2035
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• 2018

Cycloisomaltooligosaccharide glucanotransferase (CITase) was isolated from alkaliphilic Paenibacillus daejeonensis via an amino acid homology search for the reported CITase. The recombinant alkaliphilic CITase (PDCITase) from P. daejeonensis was expressed in an Escherichia coli expression system and purified as a single protein band of 111 kDa. PDCITase showed optimum activity at pH 8.0 and retained 100% of activity within a broad pH range (7.0-11.5) after 18 h, indicating alkaliphilic or alkalistable CITase properties. In addition, PDCITase produced CI-7 to CI-17, CI-18, and CI-19, which are relatively large cycloisomaltooligosaccharides yet to be reported. Therefore, these large cycloisomaltooligosaccharides can be applied to the improvement of water solubility of pharmaceutical biomaterials.

• Molecules and Cells
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• 제41권2호
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• pp.103-109
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• 2018

Calcium ions are involved in the regulation of diverse cellular processes. Fourteen genes encoding calcium binding proteins have been identified in Dictyostelium. CBP7, one of the 14 CBPs, is composed of 169 amino acids and contains four EF-hand motifs. Here, we investigated the roles of CBP7 in the development and cell migration of Dictyostelium cells and found that high levels of CBP7 exerted a negative effect on cells aggregation during development, possibly by inhibiting chemoattractant-directed cell migration. While cells lacking CBP7 exhibited normal development and chemotaxis similar that of wild-type cells, CBP7 overexpressing cells completely lost their chemotactic abilities to move toward increasing cAMP concentrations. This resulted in inhibition of cellular aggregation, a process required for forming multicellular organisms during development. Low levels of cytosolic free calcium were observed in CBP7 overexpressing cells, which was likely the underlying cause of their lack of chemotaxis. Our results demonstrate that CBP7 plays an important role in cell spreading and cell-substrate adhesion. cbp7 null cells showed decreased cell size and cell-substrate adhesion. The present study contributes to further understanding the role of calcium signaling in regulation of cell migration and development.

• 한국수정란이식학회지
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• 제29권3호
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• pp.273-281
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• 2014

This study was carried out to establish the system of OPU derived embryo production, management of recipients as well as offspring production. OPU derived embryo production system was carried out of aspiration of immature oocytes 2 times per week, total 24 times for 3 months by an ultrasonographic guided follicular aspiration system and then produced in vitro-produced blastocysts by in vitro maturation, fertilization and culture system. This work was collected total 13,866 oocytes, average $8.2{\pm}4.5$ oocytes per session and 8,170 G1 + G2 grade oocytes, average 4.8 oocytes per session by 1,692 times session of total 71 donors for 4 years from 2010 to 2013. The rate of cleavage and blastocyst developmental competence were obtained 11,825 (85.3%) and 5,032 (36.3%) that was $7.0{\pm}3.8$ cleaved embryos and $3.0{\pm}2.5$ blastocysts per session. OPU derived embryo transfer were taken place in 2, 4, 6 and 7 local governments at 2010, 2011, 2012 and 2013 for 4 years and pregnancy rate were obtained 41.2, 43.9, 46.5 and 49.7% in each years. It means that pregnancy rate was continuously improved according of every year for 4 years. Pregnancy rate was significantly different according to individual local government in which was 62.7% in B, but 24.2% in F at 2012. Paternity identification was carried out total 26 offspring in C local government of 2012 and then confirmed 100% agreement of its analysis. In conclusion, the results obtained the possibility of mass production of elite cow embryos as well as offspring by OPU derived embryo production system, of which could be decreased the required time of genetic improvement.

• Imaging Science in Dentistry
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• 제45권1호
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• pp.7-13
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• 2015

Purpose: We have developed a new method of segmenting the areas of absorbable implants and bone using region-based segmentation of micro-computed tomography (micro-CT) images, which allowed us to quantify volumetric bone-implant contact (VBIC) and volumetric absorption (VA). Materials and Methods: The simple threshold technique generally used in micro-CT analysis cannot be used to segment the areas of absorbable implants and bone. Instead, a region-based segmentation method, a region-labeling method, and subsequent morphological operations were successively applied to micro-CT images. The three-dimensional VBIC and VA of the absorbable implant were then calculated over the entire volume of the implant. Two-dimensional (2D) bone-implant contact (BIC) and bone area (BA) were also measured based on the conventional histomorphometric method. Results: VA and VBIC increased significantly with as the healing period increased (p<0.05). VBIC values were significantly correlated with VA values (p<0.05) and with 2D BIC values (p<0.05). Conclusion: It is possible to quantify VBIC and VA for absorbable implants using micro-CT analysis using a region-based segmentation method.