• Journal of Life Science
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• v.20 no.9
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• pp.1324-1331
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• 2010

Mifepristone (MIF) and Tamoxifen (TAM) have been used in the treatment of prostate cancer and breast cancer for more than a decade. MIF can induce apoptosis in both AR-positive and negative prostate cancer cells. Because of its pleiotropic ligand-receptor properties, TAM exerts cytotoxic activity in estrogen (ER)-positive and various ER.negative cancer cells. However, the molecular mechanisms of these two substances are not yet clear. In the present work, we report that the cytotoxic effects of MIF and TAM are due to the modulation of intracellular $Ca^{2+}$ level in DU-145, androgen-insensitive cells. When the cells were treated with micromolar concentrations of either MIF or TAM, the growth and viability were significantly decreased in a dose- and time-dependent manner. The apoptosis induced by MIF or TAM was further proved and analyzed by confocal laser scanning microscopy (CLSM) and fluorescence-activated cell sorting (FACS). In the cells cultivated in a normal 1.5 mM $Ca^{2+}$ medium, both MIF and TAM also induced an increase of the intracellular $Ca^{2+}$ level in a dose-dependent fashion. Since a change in calcium level could not be found in cells of the $Ca^{2+}$-free medium, the increase of intracellular $Ca^{2+}$ level might be due to an increase in extracellular calcium uptake. Our results show that the apoptotic effect was more prominent in TAM treatment compared to MIF treatment in DU-145 cells. The above findings might be due to the difference in the uppermost pathways of apoptosis induced by either MIF or TAM. When we checked the level of procaspase-8 activation, TAM showed minor level of activation, as opposed to MIF, which exerted strong activation. In both treatments, the levels of anti-apoptotic protein Bcl-2 decreased, and pro-apoptotic protein Bax level increased more than 2-fold. The activation of caspase-3, a key protease enzyme in the downstream pathway of apoptosis, was much higher in the cells treated with TAM, compared to the MIF treatment. The overall apoptotic activity shown in the present work was closely related to intracellular $Ca^{2+}$ concentration levels. Therefore, the cytotoxic activity induced by MIF and TAM might have been due to intracellular calcium modulation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.575-580
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• 2017

This study analyzed the effects of RGG box of hnRNP A1 on its subcellular localization and stabilization of hnRNP A1 over a three year period from October 2014. First, a 6R/K mutation in RGG box was generated, and pcDNA1-HA-hnRNP A1(6R/K) was constructed. The subcellular localization of hnRNP A1(6R/K) from the HeLa cells transfected with this plasmid DNA was analyzed by immunofluorescence microscopy. HA-hnRNP A1(6R/K) was found to exhibit nuclear and cytoplasmic fluorescence. The stability of hnRNP A1(6R/K) was checked by Western blot analysis using the expressed protein from the HeLa cells transfected with the pcDNA1-HA-hnRNP A1(6R/K). The results show that HA-hnRNP A1(6R/K) has a smaller size. These confirm that HA-hnRNP A1(6R/K) is localized both in the nuclear and cytoplasm, not because 6R/K mutation affects the nuclear localization of hnRNP A1, but because 6R/K mutation causes hnRNP A1(6R/K) to cleave at the mutation or near the mutation site. The cleaved protein fragment, which lacks the M9 domain (i.e. nuclear localization signal of hnRNP A1), did not exhibit nuclear fluorescence. This suggests that the arginines of RGG box in hnRNP A1 play an important role in stabilizing hnRNP A1. An analysis of the RNA-binding ability of hnRNP A1(6R/K) expressed and purified from bacteria will be a subsequent research project.

• Korean Journal of Microbiology
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• v.45 no.3
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• pp.246-250
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• 2009

Retroviruses enter host cells by membrane fusion between the viral Env proteins on the virus membrane and a virus receptor on the cellular membrane. The envelope protein of the ecotropic Moloney murine leukemia virus is synthesized as a gp85 precursor and is proteolytically cleaved into an extracellular surface unit (SU) and the transmembrane protein (TM). The cytoplasmic tail (16 amino acid; R peptide) of the TM protein is further cleaved by the viral protease during virion maturation. Unlike the wild type Env protrin bearing the R peptide, R peptide-truncated Envelope induces syncytia in susceptible cells. To understand the mechanism of R peptidetruncated Env in syncytium formation, R peptide-truncated Env expressing full-length molecular clone containing EGFP in PRR (proline rich region) of Env was constructed. This molecular clone induced syncytia in transfected NIH3T3 cells, fluorescence was detected in the cytoplasm and at the plasma membrane, while the nuclei did not stain and appeared black by fluorescence microscopy. Interestingly, virions with truncated envelope produced from transfected NIH3T3 cells induced syncytia in NIH3T3 cells, but fluorescence was not detected in the same infected cells. It is believed that cell-free viruses direct the fusion of neighboring cells without infection. Our data suggests that use of EGFP-tagged envelope for monitoring syncytium is a sensitive and convenient method. We also found that virion incorporated the R peptide-truncated Env is able to induce the formation of syncytia by fusion from without.

• Conservation Science in Museum
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• v.29
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• pp.1-32
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• 2023

The Paintings of a 60^th Wedding Anniversary Ceremony Created by an Unknown Painter (Deoksu 6375), housed by the National Museum of Korea, is a five-panel painting book depicting scenes from a wedding ceremony. Hoehonrye is a type of repeated wedding ceremony to commemorate a couple's 60th wedding anniversary with congratulations from the community. The paintings of the book record five scenes from the wedding: jeoninrye, a ceremony where the groom brings a wooden wild goose to the bride's house; gyoberye, the groom and the bride bowing to each other; heosurye, pouring liquor to toast to the couple's longevity; jeopbin, offering tea to guests; and a banquet to celebrates the couple's 60th wedding anniversary. The book describes figures, buildings and a variety of items in detail with delicate brushstrokes. The techniques were examined using microscopy, infrared, and X-ray irradiation and hyperspectral imaging analysis. The invisible parts were examined to identify the rough sketch and distinguish pigments and dyes used for each color. The components of the pigments were determined by X-ray fluorescence analysis, while the dyes were identified by UV-vis spectrometry. Microscope observation revealed that the fabric used for the paintings was raw silk thread with almost no fiber twist, and plain silk fabric. Hyperspectral imaging analysis, X-ray fluorescence analysis, and UV-vis spectrometry confirmed that the white pigment was white lead and the black was chinese ink. The red pigments were using red clay, cinnabar, and a mixture of cinnabar and minium. Brown was made using red clay and organic dyes, and yellow using gamboge. Green was identified as indigo, malachite, chrome green, barium sulfide, and blue as azurite, smalt, and indigo. The purple dye was estimated as a mixture of indigo and cochineal, and gold parts were used gold powder. Hyperspectral images were distinguished parts damaged and conservation treatment area.

• Journal of Life Science
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• v.24 no.10
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• pp.1039-1045
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• 2014

This study analyzed whether human chorionic gonadotropin (hCG) induces ER stress via the IRE/XBP1 pathway in mouse Leydig tumor (mLTC-1) cells. In a previous study, we demonstrated that the unfolding protein response (UPR) plays an important role in the expression of steroidogenic enzymes by modulating the ATF6 pathway, as well as ER stress-mediated apoptosis in hCG-stimulated Leydig cells. Although UPR signaling has been reported to regulate the IRE1/XBP1 pathway, it is not known whether hCG-induced ER stress in Leydig cells can activate the pathway. To investigate the activation of the IRE1/XBP1 pathway in mLTC-1 cells after hCG treatment, we performed a Western blot analysis to detect the phospho-IRE1 protein and an RT-PCR analysis to validate splicing of XBP1 mRNA. We used ER stress-activated indicator (ERAI) constructs for monitoring the activity of IRE1 and then analyzed by fluorescence microscopy and flow cytometry. The expression levels of the phospho-IRE1 protein markedly increased in response to the hCG treatment. In the mLTC-1 cells transfected with an F-XBP1-venus/F-$XBP1{\Delta}DBD$-venus construct, the hCG treatment led to the appearance of green fluorescent cells and detectable fluorescence in the nucleus and cytosol, respectively. In addition, splicing of XBP1 mRNA significantly increased after the hCG treatment. Taken together, these results indicate that hCG-induced ER stress leads to activation of the IRE1/XBP pathway in Leydig cells.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.304-314
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• 2010

This study was carried out to find out potential use of ochre as an agent to reduce phosphorus content in water. Ochre is a by-product from treatment of acid mine drainage (AMD) which is composed mostly of $Fe_2O_3$, $Fe_2O_3{\cdot}H_2O$, $FeO{\cdot}OH$ and $Fe(OH)_3$. Three ochre samples (ochre-H, ochre-D and ochre-S) were collected from three treatment facilities in Gangwon province. Physico-chemical characteristics of three ochre samples including pH, electrical conductivity, total phosphorus, available phosphorus, particle size distribution were analyzed. Scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and X-ray fluorescence (XRF) analysis were also carried out. In addition, experiments for phosphorus removal from water was performed. Calcium content of ochre-H was higher than that of ochre-D and ochre-S, whereas iron content of ochre-H was lower than that of ochre-D and ochre-S. All the phosphorus in water up to maximum 191,411 mg $kg^{-1}$ per unit mass of ochre was removed with ochre-H. Ochre has immense potential as an agent to reduce phosphorus content in water.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.386-386
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• 2012

For white light emitting diode (LED) applications, it has been reported that Y3Al5O12:Ce3+ (YAG:Ce) in nano-sized phosphor performs better than it does in micro-sized particles. This is because nano-sized YAG:Ce can reduce internal light scattering when coated onto a blue LED surface. Recently, there have been many reports on the synthesis of nano-sized YAG particles using bottom-up method, such as co-precipitation method, sol-gel process, hydrothermal method, solvothermal method, and glycothermal method. However, there has been no report using top-down method. Top-down method has advantages than bottom-up method, such as large scale production and easy control of doping concentration and particle size. Therefore, in this study, nano-sized YAG:Ce phosphors were synthesized by a high energy beads milling process with varying beads size, milling time and milling steps. The beads milling process was performed by Laboratory Mill MINICER with ZrO2 beads. The phase identity and morphology of nano-sized YAG:Ce were characterized by X-ray powder diffraction (XRD) and field-emission scanning electron microscopy (FESEM), respectively. By controlling beads size, milling time and milling steps, we synthesized a size-tunable and uniform nano-sized YAG:Ce phosphors which average diameters were 100, 85 and 40 nm, respectively. After milling, there was no impurity and all of the peaks were in good agreement with YAG (JCPDS No. 33-0040). Luminescence and quantum efficiency (QE) of nano-sized YAG:Ce phosphors were measured by fluorescence spectrometer and QE measuring instrument, respectively. The synthesized YAG:Ce absorbed light efficiently in the visible region of 400-500 nm, and showed single broadband emission peaked at 550 nm with 50% of QE. As a result, by considering above results, high energy beads milling process could be a facile and reproducible synthesis method for nano-sized YAG:Ce phosphors.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.2
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• pp.97-106
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• 2010

Aim of the study: An alternative source of adult stem cells that could be obtained in large quantities, under local anesthesia, with minimal discomfort would be advantageous. Adipose tissue could be processed to obtain a fibroblast-like population of cells or adipose tissue-derived stromal cells (ATSCs). This study was performed to confirm the availability of ATSCs in bone tissue engineering. Materials amp; Methods: In this study, adipose tissue-derived mesenchymal stem cell was extracted from the liposuctioned abdominal fat of 24-old human and cultivated, and the stem cell surface markers of CD 105 and SCF-R were confirmed by immunofluorescent staining. The proliferation of bone marrow mesenchymal stem cell and ATSCs were compared, and evaluated the osteogenic differentiation of ATSCs in a specific osteogenic induction medium. Osteogenic differentiation was assessed by von Kossa and alkaline phosphatase staining. Expression of osteocyte specific BMP-2, ALP, Cbfa-1, Osteopontin and osteocalcin were confirmed by RT-PCR. With differentiation of ATSCs, calcium concentration was assayed, and osteocalcin was evaluated by ELISA (Enzyme-linked immunosorbant assay). The bone formation by 5-week implantation of HA/TCP block loaded with bone marrow mesenchymal stem cells and ATSCs in the subcutaneous pocket of nude mouse was evaluated by histologic analysis. Results: ATSCs incubated in the osteogenic medium were stained positively for von Kossa and alkaline phosphatase staining. Expression of osteocyte specific genes was also detected. ATSCs could be easily identified through fluorescence microscopy, and bone formation in vivo was confirmed by using ATSC-loaded HA/TCP scaffold. Conclusions: The present results show that ATSCs have an ability to differentiate into osteoblasts and formed bone in vitro and in vivo. So ATSCs may be an ideal source for further experiments on stem cell biology and bone tissue engineering.

• Korean journal of applied entomology
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• v.38 no.2
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• pp.139-144
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• 1999

We have now constructed a novel recombinant baculovirus producing fusion protein with Autogrqha c.uliforrzica nuclear polyhedrosis virus (AcNPV) polyhedrin and green fluorescent protein (GFP). The fusion protein expressed by the recombinant baculovirus in insect cells was characterized. The GFP gene was introduced under the control of polyhedrin gene promoter of AcNPV, by fusion in the front or back of intact polyhedrin gene. The recombinant baculoviruses were named as Ac-GFPPOL or Ac-POLGFP. respectively. As expected, the 56 kDa fusion protein was expressed in the recombinant virus-infected cells. Interestingly. however, the fluorescence of GFP in the cells infected with Ac- POLGFP was only detected within the nuclei. and that was observed as polyhedra-like granular particles. In the microscopy of cells infected with Ac-GFPPOL, furthermore, GFP was detected in both cytoplasm and nuclei although most of GFP were present within the nuclei. However, fusion protein produced by recombinant virus did not form polyhedra although the fusion protein was fused with polyhedrin and GFP. It is suggested that difference of GFP location in the infected cells appear to be involved in the region of polyhedrin in the fusion protein, and the polyhedrin in the fusion protein might be responsible for the polyhedra-like granular particles present within nuclei.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.11a
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• pp.41.1-41.1
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• 2009

Aerosol Deposition (AD) is anovel way to fabricate bioactive ceramic coatings in biomedical implants and prostheses applications. In the present work, silicon-substituted hydroxyapatite (HA) coatings on commercially pure titanium were prepared by aerosol deposition using Si-HA powders. The incorporation of silicon in the HA lattice is known to improve the bioactivity of the HA, makingsilicon-substitute HA an attractive alternative to pure HA in biomedical applications. Si-HA powders with the chemical formula $Ca_{10}(PO_4)_6-x(SiO_4)x(OH)_2-x$, having silicon contents up to x=0.5 (1.4 wt%), were synthesized by solid-state reaction of $Ca_2P_2O_7$, $CaCO_3$, and $SiO_2$. The Si-HA powders were characterized by X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF), and Fourier transform infrared spectroscopy(FT-IR). The corresponding coatings were also analyzed by XRD, scanning electron microscopy (SEM), and electron probe microanalyzer (EPMA). The results revealed that a single-phase Si-HA was obtained without any secondary phases such as $\alpha$- or $\beta$-tricalcium phosphate (TCP) for both the powders and the coatings.The Si-HA coating was about $5\;{\mu}m$ thick, had a densemicrostructure with no cracks or pores. In addition, the proliferation and alkaline phosphatase (ALP) activity of MC3T3-E1 preosteoblast cells grown on the Si-HA coatings were significantly higher than those on the bare Ti and pure HA coating. These results revealed the stimulatory effects induced by siliconsubstitution on the cellular response to the HA coating.