• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.2789-2800
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• 2013

Background: The aim of this systematic review was to investigate whether stem cells could be effectively applied in targeted therapy of breast cancer. Material and Method: A systematic literature search was performed for original articles published from January 2007 until May 2012. Results: Nine studies met the inclusion criteria for phase I or II clinical trials, of which three used stem cells as vehicles, two trials used autologous hematopoetic stem cells and in four trials cancer stem cells were targeted. Mesenchymal stem cells (MSCs) were applied as cellular vehicles to transfer therapeutic agents. Cell therapy with MSC can successfully target resistant cancers. Cancer stem cells were selectively targeted via a proteasome-dependent suicide gene leading to tumor regression. $Wnt/{\beta}$-catenin signaling pathway has been also evidenced to be an attractive CSC-target. Conclusions: This systematic review focused on two different concepts of stem cells and breast cancer marking a turning point in the trials that applied stem cells as cellular vehicles for targeted delivery therapy as well as CSC-targeted therapies. Applying stem cells as targeted therapy could be an effective therapeutic approach for treatment of breast cancer in the clinic and in therapeutic marketing; however this needs to be confirmed with further clinical investigations.

• Journal of Korea Foundry Society
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• v.33 no.3
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• pp.127-133
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• 2013

The influences of a small amount of CaO addition on the microstructure and corrosion behavior of AZ81 casting alloy have been investigated by means of optical microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, immersion and electrochemical tests. The added CaO led to the refinement of ${\alpha}$-Mg grains and the decrease in ${\beta}$ precipitate content by the formation of an $Al_2Ca$ phase. The AZ81-CaO alloy had a better corrosion resistance than the AZ81 alloy. The microstructural characterization on the corroded surface revealed that the enhanced corrosion resistance of the CaO-containing alloy may well be ascribed to the increased barrier effect of precipitates formed more continuously along the grain boundaries and the incorporation of Al and Ca elements into the corrosion film, by which it became more protective.

• Preventive Nutrition and Food Science
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• v.11 no.2
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• pp.100-104
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• 2006

The in vitro antimicrobial and antioxidant activities of the essential oil and methanol extracts of Ledum palustre L. were investigated. Using GC-MS analysis, we identified 37 compounds in the essential oil, constituting 87.58% of the total oil. There are several monoterpenes, of which sabinene is the major compound ($16{\sim}17%$). There are several oxygenated monoterpenes of which terpinen-4-ol(7.6%) and myrtenal (3.5%) are the main constituents. $\beta$-Selinene, a-selinene, $\gamma$-elemene, a-caryophyllene are the main sesquiterpenes ($2{\sim}6%$ range). The oil strongly reduced the diphenylpicrylhydrazyl radical ($IC_{50}=1.56{\mu}g/mL$) formation and exhibited a hydroxyl radical scavenging effect in the $Fe^{3+}-EDTA-H_2O_2$ deoxyribose system ($IC_{50}=2.7{\mu}g/mL$), and also inhibited the nonenzymatic lipid peroxidation of rat liver homogenate ($IC_{50}=13.5{\mu}g/mL$). The polar phase of the extract showed antioxidant activity. The oil showed antimicrobial activity against Streptococcus pneumoniae, Clostridium perfringens, Candida albicans, Mycobacterium smegmatis, Acinetobacter lwoffii and Candida krusei while the water-insoluble parts of the methanolic extracts exhibited slight or no activity. This study confirms that the essential oil of Ledum palustre L. possesses antioxidant and low antimicrobial properties in vitro.

• Journal of Korea Foundry Society
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• v.36 no.6
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• pp.215-221
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• 2016

In a recent study, the microstructures and mechanical properties of AM80-xSn magnesium alloys with semi solid casting and hot extrusion process were investigated. With increasing Sn content, the amount of ${\beta}$(Mg2Sn) phase increased, while the ${\alpha}-Mg$ dendritic size decreased. The hardness was increased by the Mg2Sn as the Sn content increased. With increasing Sn content, permanent mold cast and semi solid cast AM80 Mg alloy showed less reduction of hardness and also of extruded AM80 Mg alloy after annealing. In the case of the mechanical properties, the extruded semi solid casting AM80 Mg alloy showed higher tensile strength and yield strength with increasing Sn content compared to the extruded permanent mold cast AM80 Mg alloy at room temperature.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.554-554
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• 2000

To improve mechanical properties of Cu-Al-Ni alloy by the grain refinement, Cu-Al-Ni SMA ribbons were fabricated by melt spinning apparatus. The variations of microstructure, mechanical properties and transformation characteristics with the condition of rapid solidification and annealing time-temperature were investigated in Cu-Al-Ni SMA ribbons. The ribbons fabricated by melt spinning obtained around 1.5nm in width and 50-60${\mu}{\textrm}{m}$ in thickness. With increasing wheel speed in order of 10m/s, 15m/s, 20m/s, 30m/s and 3m/s, the grain size was decreased in order of 10${\mu}{\textrm}{m}$, 6.25${\mu}{\textrm}{m}$, 5.5${\mu}{\textrm}{m}$, 3${\mu}{\textrm}{m}$ and 3${\mu}{\textrm}{m}$. $M_{s}$ and $A_{s}$ temperature were decreased with decreasing grain size. By X-ray diffraction test, ordered $\beta$$_1$ phase was observed in all the SMA ribbons and the volume friction of it was increased with increasing wheel speed. With increasing wheel speed, strain was increased from 4.2% to 5.8% and fracture mode has changed from mixture of intergranular and dimple fracture to mixture of fiber structure and dimple fracture. The grain size of ribbon heat-treated at $600^{\circ}C$ was increased with increasing time. In the heat-treated ribbons at 55$0^{\circ}C$, ${\gamma}$$_2$ phases were observed.d.d.

• Biomolecules & Therapeutics
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• v.17 no.1
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• pp.86-91
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• 2009

In our ongoing search for biological components from the Korea endemic plants, the MeOH extract of Ailanthus altissima leaves (Simaroubaceae) showed cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX) dual inhibitory activity by assessing their effects on the production of prostaglandin $D_2$ ($PGD_2$) and leukotriene $C_4$ ($LTC_4$) in mouse bone marrow-derived mast cells (BMMCs). In further study, eight compounds, squalene (1), ${\beta}$-sitosterol (2), scopoletin (3), quercetin (4), luteolin (5), astragalin (6), scopolin (7), and daucosterol (8) were isolated, the chemical structures were elucidated on the basis of physicochemical and spectroscopic data and by comparison with those of published literatures. Among the compounds, 2, 4, and 5 strongly inhibited both the COX-2-dependent PGD2 generation with $IC_{50}$ values of 2.6, 7.3 and 2.5 ${\mu}M$, respectively and the generation of $LTC_4$ in the 5-LOX dependent phase with $IC_{50}$ values of 2.0, 5.1 and 1.8 ${\mu}M$, respectively, which suggest that the anti-inflammatory activity of A. altissima might occur in part via the inhibition of both $PGD_2$ and $LTC_4$ generation by 2, 4 and 5.

• Journal of the Korean Society for Heat Treatment
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• v.17 no.5
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• pp.299-304
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• 2004

Influence of Ca addition on microstructure and room temperature mechanical properties has been studied for AZ31(Mg-3%Al-1%Zn-0.2%Mn)-(0~0.5)%Ca wrought alloys, based on experimental results from metallography, X-ray diffractometry and mechanical tests. Yield strength, ultimate tensile strength and hardness of the alloys increased remarkably with increasing Ca content, whereas elongation was deteriorated continuously. Microstructural examination revealed that Ca addition efficiently refined grains of ${\alpha}$(Mg) phase and that some of the Ca dissolved in ${\beta}(Mg_{17}Al_{12})$ precipitates. The former and the latter facts are thought to be responsible for improved strength and loss of ductility of the AZ31+Ca wrought alloys, respectively.

• Korean Journal of Materials Research
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• v.27 no.3
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• pp.172-178
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• 2017

The aim of this study is to consider the effect hydrogen on dezincification behavior of Cu-Zn alloys. The investigations include microstructural observations with scanning electron microscope and chemical composition analysis with energy dispersive spectrometer. The dezincification layer was found to occur in high pressure hydrogen atmosphere, not in air atmosphere. In addition, the layers penetrated into the inner side along the grain boundaries in the case of hydrogen condition. The shape of the dezincification layers was porous because of Zn dissolution from the ${\alpha}$ or ${\beta}$ phase. In the case of stress corrosion cracks formed in the Cu-Zn microstructure, the dezincification phenomenon with porous voids was also accompanied by grain boundary cracking.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.134-134
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• 1998

The modulation of glycosidase activity by inhibitors is of great interest. Such compounds have been shown to be important tools in mechanistic studies on glycohydrolase as well as having promising therapeutic application. An ${\alpha}$-glucosidase inhibitor was isolated from culture filterates of Penicillium sp. The inhibitor was active against ${\alpha}$-glucosidase isolated from yeast and porcine small intestine. However, it showed no inhibition to Aspergillus ${\alpha}$-galactosidase, Escherichia coli ${\beta}$-galactosidase, and jack bean ${\alpha}$-mannosidase. The inhibitor was highly soluble in ether, methanol and chloroform. The inhibitor was purified using silica gel, Sephadex LH-20 column chromatography and reverse-phase HPLC. The inhibitory compound designated PA-7(IC$\sub$50/=35$\mu\textrm{g}$) was obtained as white powder. The structure of PA-7 was determined with spectroscopic data of EI-MS, FAB-MS, $^1$H, and $\^$13/C NMR. The inhibitor has a diketopiperazine moiety.

• Korean Journal of Materials Research
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• v.13 no.2
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• pp.101-105
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• 2003

In this study, we have investigated the availability of the electroless Ni-B plating for a diffusion barrier of the bus electrode. The Ni-B layer of 1$\beta$: thick was electroless deposited on the electroplated Cu bus electrode for AC plasma display. The layer was to encapsulate Cu bus electrode to prevent from its oxidation and to serve as a diffusion barrier against Cu contamination of the transparent dielectric layer in AC plasma display. The microstructure of the as-plated barrier layer was made of an amorphous phase and the structure was converted to crystalline at about 30$0^{\circ}C$. The concentration of boron was about 5∼6 wt.% in the electroless Ni-B deposit regardless of DMAB concentration. The electroless Ni-B deposit was coated on the surface of the electroplated Cu bus electrode uniformly. And the electroless Ni-B plating was found to be an appropriate process to form the diffusion barrier.