• Korean Journal of Plant Resources
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• v.31 no.3
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• pp.211-217
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• 2018

Hibiscus syriacus (H. syriacus) as the national flower of Korea has been used as the herbal medicine in Asia. In this study, we evaluated the anti-inflammatory effect of 70% ethanol extracts from the root of Hibiscus syriacus (RHS-E70) and elucidated the potential signaling pathway in LPS-stimulated RAW264.7 cells. RHS-E70 dose-dependently suppressed NO production by inhibiting iNOS and IL-${\beta}$ expression in LPS-stimulated RAW264.7 cells. RHS-E70 inhibited the phosphorylation and degradation of $I{\kappa}B-{\alpha}$, which contributed to the inhibition of p65 nuclear accumulation and NF-${\kappa}B$ activation. Furthermore, RHS-E70 suppressed the phosphorylation of ERK1/2 and p38, which results in the inhibition of ATF2 phosphorylation and subsequent nuclear accumulation. These results indicate that RHS-E70 may exert anti-inflammatory activity by inhibiting NF-${\kappa}B$ and MAPK/ATF2 signaling. From these findings, RHS-E70 has potential to be a candidate for the development of chemopreventive or therapeutic agents for the inflammatory diseases.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.2
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• pp.83-90
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• 2000

A simple low-cost and small size 1.88-198 GHz Band RF power amplifier module is developed for IMT2000 repeater. The power amplifier consists of two stage amplifiers that the first stage amplifier is drive amplifier using discrete type P-HEMT (ATF-34143, 800 micron gate width, Agilent Technologies) and the second is power amplifier with 300Bm 1dB gain compression point using GaAs FET(EFA240D-SOT89, 2400 micron gate width, Excelics Semiconductor). this power amplifier module feature a 29.5dBm 1dB gain compression point, 29.5dB gain, 42dBm 3rd order intercept point(OIP3) and -10dB/-l2dB input/output return loss over the 1880-1980 MHz. This PA module is fully integrated using MIC technology into a small size and design by full nonlinear design technologies. The dimensions of this PA module are 42(L) $\times$ 34(W) mm.

• Journal of Life Science
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• v.22 no.12
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• pp.1672-1679
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• 2012

The effect of high stocking density (HSD) on the expression of stress and lipid metabolism associated genes in the liver of broiler chickens was examined by chicken genome array analysis. The chickens in a control group were randomly assigned to a $495cm^2/bird$ stocking density, whereas the chickens in a HSD group were arranged in a $245cm^2/bird$ stocking density with feeding ad libitum for 35 days. The chickens assigned to the HSD group had a significantly lower body weight, weight gain, and feed intake compared with those of the control group (p<0.05). The mortality of chickens was higher in the HSD group than in the control group. The microarray analysis indicated up-regulation of stress associated genes such as HMGCR, $HSP90{\alpha}$, HSPA5 (GRP78/Bip), DNAJC3 and ATF4, and down-regulation of interferon-${\gamma}$ and PDCD4 genes. The endoplasmic reticulum stress associated genes, HSPA5 (GRP78/Bip), DNAJC3 and ATF4, were highly expressed in the HSD group. The genes, ACSL5, TMEM195 and ELOVL6, involved in fatty acid synthesis, were elevated in the HSD group. The genes, ACAA1, ACOX1, EHHADH, LOC423347 and CPT1A, related to fatty acid oxidation, were also activated in the HSD group. These results suggest that a HSD rearing system stimulates the genes associated with fatty acid synthesis as well as fatty acid oxidation in the liver of broiler chickens.

• Journal of Life Science
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• v.22 no.2
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• pp.281-284
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• 2012

This study demonstrated that upregulation of gene expression of endoplasmic reticulum (ER) stress chaperones (Bip, ERp29, calnexin, and PDI), ER stress sensors (PERK, ATF6, and Ire1), and cAMP phosphodiesterase 7A1 (cAMP PDE7A1) was induced by ER stresses in FRTL5 cells. While removing A23187 from the culture medium restored upregulation of cAMP PDE7A1 gene expression, removal of thapsigargin did not recover its expression. In addition, cAMP PDE7A1 gene expression was strongly inhibited by treatment with A23187 combined with thyroid stimulating hormone (TSH). The results are the first to show that ER stress induces cAMP PDE7A1 gene expression.

• BMB Reports
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• v.32 no.4
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• pp.379-384
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• 1999

Taxol, a natural product with significant anti-tumor activity, stabilizes microtubules and arrests cells in the G2/M phase of the cell cycle. It has been reported that taxol has additional effects on the cell such as an increase in tyrosine phosphorylation of proteins and activation of mitogen-activated protein (MAP) kinase. This phosphorylated kinase translocates into the nucleus and phosphorylates its substrate c-jun, c-fos, ATF2, and ATF3. The MAP kinase family is comprised of key regulatory proteins that control the cellular response to both proliferation and stress signals. First examination was cytotoxicity and apoptosis-induced concentration with paclitaxel in HeLa cell. A half-maximal inhibition of cell proliferation ($IC_{50}$) occurred at 13 nM paclitaxel. When DNA fragmentation was analyzed by agarose gel electrophoresis, a nucleosomal ladder became evident 24 h after a taxol (50 nM) addition to the cells. In addition, an apoptotic body was detected by electron microscopy. Taxol-treated cells were arrested at the S phase at 10 nM. Treatment of 50 nM taxol activated the extracellular signal-regulated protein kinase (ERK1), and a fraction of the activated MAP kinases entered the nucleus. It was also discovered that nucleus substrates c-jun was phosphorylated and activated in the cell. The activated ERK1 could subsequently translocate into the nucleus and phosphorylate its substrate c-jun as well. This study suggests that taxol-induced apoptosis might be related with signal transduction via MAP kinases.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.8
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• pp.1591-1597
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• 2003

In this paper, Active Resonator Oscillator using active inductor and active capacitor with HEMTs(agilent ATF­34143) is designed and fabricated. Active inductor with ­25$\Omega$ and 2.4nH in 5.5GHz frequency band and Active capacitor with ­14$\Omega$ and 0.35pF is designed. Active Resonator Oscillator for LO in ISM band(5.8GHz) is designed with active inductor and active capacitor. Active Resonator Oscillator has been simulated by Agilent ADS 2002C. Active Resonator oscillator implemented on the substrate which has the relative dielectric constant of 3.38, the height of 0.508mm, and metal thickness of 0.018mm. This Active Resonator Oscillator shows the oscillation frequency of 5.68GHz with the output power of ­3.6㏈m and phase noise of ­81㏈c/Hz at the offset frequency of 100KHz.

• Explosives and Blasting
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• v.38 no.4
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• pp.26-36
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• 2020

With the increase of expansion and use of the underground space, the possibility of an underground explosion by terrorists is increasing. In this study, after modeling a circular tunnel excavated at a depth of 50m, an explosion load was applied to the inside of the tunnel. As for the explosion load, the explosion load of the maximum explosive amount for six types of vehicle booms proposed by ATF (Bureau of Alcohol, Tobacco, and Firearms) was calculated. For the rock mass around the circular tunnel, three types of rock grades were selected according to the support pattern suggested in the domestic tunnel design. Nonlinear dynamic analysis was performed to evaluate the influence of the ground structure by examining the surface displacement using the explosion load and rock mass characteristics as parameters. As a result of the analysis, for grade 1 rock, the influence on the uplift of the surface should be considered, and for grade 2 and 3 rocks, the influence on a differential settlement should be considered. In particular, for grade 3 rocks, detailed analysis is required for ground-structure interaction within 40m. Also, it is considered that the influence of Young's modulus is the main factor for the surface displacement.

• Journal of Microbiology and Biotechnology
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• v.32 no.5
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• pp.645-656
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• 2022

Gossypol, a natural phenolic aldehyde present in cotton plants, was originally used as a means of contraception, but is currently being studied for its anti-proliferative and anti-metastatic effects on various cancers. However, the intracellular mechanism of action regarding the effects of gossypol on pancreatic cancer cells remains unclear. Here, we investigated the anti-cancer effects of gossypol on human pancreatic cancer cells (BxPC-3 and MIA PaCa-2). Cell counting kit-8 assays, annexin V/propidium iodide staining assays, and transmission electron microscopy showed that gossypol induced apoptotic cell death and apoptotic body formation in both cell lines. RNA sequencing analysis also showed that gossypol increased the mRNA levels of CCAAT/enhancer-binding protein homologous protein (CHOP) and activating transcription factor 3 (ATF3) in pancreatic cancer cell lines. In addition, gossypol facilitated the cleavage of caspase-3 via protein kinase RNA-like ER kinase (PERK), CHOP, and Bax/Bcl-2 upregulation in both cells, whereas the upregulation of ATF was limited to BxPC-3 cells. Finally, a three-dimensional culture experiment confirmed the successful suppression of cancer cell spheroids via gossypol treatment. Taken together, our data suggest that gossypol may trigger apoptosis in pancreatic cancer cells via the PERK-CHOP signaling pathway. These findings propose a promising therapeutic approach to pancreatic cancer treatment using gossypol.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.6
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• pp.239-246
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• 2007

Expressions of endoplasmic reticulum stress response (ERSR) genes were examined during the neuronal differentiation of rat fetal cortical precursor cells (rCPC) and rat pheochromocytoma PC12 cells. When rCPC were differentiated into neuronal cells for 7 days, early stem cell marker, nest in, expression was decreased from day 4, and neuronal markers such as neurofilament-L, -M and Tuj1 were increased after day 4. In this condition, expressions of BIP, ATF6, and phosphorylated PERK as well as their down stream signaling molecules such as CHOP, ATF4, XBP1, GADD34, Nrf2 and $p58^{IPK}$ were significantly increased, suggesting the induction of ERSR during neuronal differentiation of rCPC. ERSR was also induced during the differentiation of PC12 cells for 9 days with NGF. Neurofilament-L transcript was time-dependently increased. Both mRNA and protein levels of Tuj1 were increased after the induction, and the significant increase in NeuN was observed at day 9. Similar to the expression patterns of neuronal markers, BIP/GRP78 and CHOP mRNAs were highly increased at day 9, and ATF4 mRNA was also increased from day 7. These results strongly suggest the induction and possible role of ERSR in neuronal differentiation process. Further study to identify targets responsible for neuronal induction will be necessary.

• Journal of Life Science
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• v.24 no.9
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• pp.967-972
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• 2014

In the present study, we prepared eighty-five different kinds of lees extracts and their solvent fractions and investigated their anti-proliferative activities against human colorectal cancer HCT116 cells. HCT116 cells were treated with eighty-five solvent fractions of lees extracts and then cell viability was measured using MTS assay. Among the treated solvent fractions, three solvent fractions (KSD-E1-3, KSD-E2-3, and KSD-E4-3) were selected based on cell viability assay. In addition, we performed an oligo DNA microarray analysis to analyze the gene expression changes by treatment of KSD-E1-3 in HCT116 cells. Among the upregulated genes, we selected 4 genes (NAG-1, ATF3, p21, and DDIT3) and performed RT-PCR using gene-specific primers. Among the treated solvent fractions, KSD-E1-3 dramatically induced the expressions of the four selected genes. In addition, we investigated whether the upregulations of those genes were dependent on the transcription factor p53's presence using p53 null HCT116 cells. The results indicate that the upregulations of NAG-1, ATF3, and DDIT3 are not dependent on the p53 presence, whereas p21 is dependent on the p53 presence. These findings may help to understand the molecular mechanisms of the anti-proliferative activity mediated by rice wine lees in human colorectal cancer cells.