• Journal of Life Science
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• v.18 no.3
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• pp.336-343
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• 2008

Histone deacetylases (HDACs) inhibitors have emerged as the accessory therapeutic agents for various human cancers, since they can block the activity of specific HDACs, restore the expression of some tumor suppressor genes and induce cell differentiation, cell cycle arrest and apoptosis in vitro and in vivo. In the present study, we investigated that the effect of trichostatin A (TSA), an HDAC inhibitor, on the cell growth and apoptosis, and its effect on the nuclear factor-kappaB $(NF-{\kappa}B)$ activity in 267B1 human prostate epithelial cells. Exposure of 267B1 cells to TSA resulted in growth inhibition and apoptosis induction in and dose-dependent manners as measured by fluorescence microscopy, agarose gel electrophoresis and flow cytometry analysis. TSA treatment inhibited the levels of IAP family members such as c-IAP-1 and c-IAP-2 and induced the proteolytic activation of caspase-3, -8 and -9, which were associated with concomitant degradation of poly (ADP-ribose)-polymerase, ${\beta}-catenin$ and laminin B proteins. The increase in apoptosis by TSA was connected with the translocation of $NF-{\kappa}B$ from cytosol to nucleus, increase of the DNA binding as well as promoter activity of $NF-{\kappa}B$, and degradation of cytosolic inhibitor of KappaB $(I{\kappa}B)-{\alpha}$ protein. We therefore concluded that TSA demonstrated anti-proliferative and apoptosis-inducing effects on 267B1 cells in vitro, and that the activation of caspases and $NF-{\kappa}B$ may play important roles in its mechanism of action. Although further studies are needed, these findings provided important insights into the possible molecular mechanisms of the anti-cancer activity of TSA.

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.267-267
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• 2003

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.3
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• pp.267-276
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• 2020

T In the present study, we investigated the effect of oncogenic H-Ras on rat mdr1b expression in NIH3T3 cells. The constitutive expression of H-Ras^V12 was found to downregulate the mdr1b promoter activity and mdr1b mRNA expression. The doxorubicin-induced mdr1b promoter activity of the H-Ras^V12 expressing NIH3T3 cells was markedly lower than that of control NIH3T3 cells. Additionally, there is a positive correlation between the level of H-Ras^V12 expression and a sensitivity to doxorubicin toxicity. To examine the detailed mechanism of H-Ras^V12-mediated down-regulation of mdr1b expression, antioxidant N-acetylcysteine (NAC) and NADPH oxidase inhibitor diphenylene iodonium (DPI) were used. Pretreating cells with either NAC or DPI significantly enhanced the oncogenic H-Ras-mediated down-regulation of mdr1b expression and markedly prevented doxorubicin-induced cell death. Moreover, NAC and DPI treatment led to a decrease in ERK activity, and the ERK inhibitors PD98059 or U0126 enhanced the mdr1b-Luc activity of H-Ras^V12-NIH3T3 and reduced doxorubicin-induced apoptosis. These data suggest that Ras^V12 expression could downregulate mdr1b expression through intracellular reactive oxygen species (ROS) production, and ERK activation induced by ROS, is at least in part, contributed to the downregulation of mdr1b expression.

• Biomedical Science Letters
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• v.26 no.4
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• pp.267-274
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• 2020

The larva of Protaetia brevitarsis Lewis (P. brevitarsis), edible insect, is traditionally consumed as alternative source of nutrients and has various health benefits. However, the exact pharmaceutical effects of P. brevitarsis on inflammatory response are still not well understood. Thus, we investigated the anti-inflammatory effects and mechanisms of P. brevitarsis in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. We investigated the effects of P. brevitarsis on the expression levels of inflammatory-related genes, including inflammatory cytokines, prostaglandin E2 (PGE2), cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) in LPS-stimulated RAW264.7 cells. To understand the anti-inflammatory mechanism of P. brevitarsis, we explored the regulatory effect of P. brevitarsis on nuclear factor (NF)-κB and caspase-1 activation. The findings of this study demonstrated that P. brevitarsis inhibits the LPS-induced inflammatory cytokine and PGE2 levels, as well as COX-2 and iNOS expression. Moreover, we confirmed that the anti-inflammatory effect of P. brevitarsis occurs via suppression of the activation of NF-κB and caspase-1. Conclusively, these findings provide experimental evidence that P. brevitarsis may be useful candidate for the treatment of inflammatory-related diseases.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.2
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• pp.127-132
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• 1983

An investigation was performed to reveal the relation between production and decomposition of the Miscanthus sinensis and Arundinella hirta grasslands in Mt. Kwanak. 1. The total annual litter productions of M. sinensis grassland A, B and A, hirta grassland were 2,267.12, 943.44 and 1,228.45 g/m$^{2}$, respectively. 2. The decay constants of litters of M. sinensis grassland A, B and A. hirta grassland were 0.732, 0.411 and 0.877. 3. The time required for the decomposition of half of the accumulated organic matter of M. sinensis A,B and 4. hirta were 0.9, 1.7 and 0.8 years, for 95% of elimination 4.1, 7.3 and 3.4 years, and for 99% of elimination 6.8, 12.2 and 5.7 years respectively. 4. The decomposition rate of grass litters was affected by the soil water content and grass species.

• Korean Journal of Microbiology
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• v.36 no.4
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• pp.267-272
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• 2000

A 1.7-kb fragment containing the nodD1 genes of Bradyrhizobium sp. (Cassia) CN9135 was amplified by PCR with primers based on B. japonicum USDA110. This fragment was cloned and sequenced. Analysis of the sequence showed open reading frames highly homologous to nodD1 from other bradyrhizobial sources. The sequence showed higher homology to nodD1 gene of B. elkanii than to those from b. japonicum. Our results suggest that Bradyrhizobium sp. (Cassia) CN9135 may be more closely related to B. elkanii than to B. japonicum.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2006.10a
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• pp.255-267
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• 2006

LTCC Technology is very suitable for 60 GHz application $\blacksquare$ LTCC substrate shows low loss at 60 GHz. - low insertion and return losses $\blacksquare$ Microstrip or CBCPW line is sultable for transmission lines at 60 GHz. - low loss (0.1dB/mm) $\blacksquare$ Single ribbbon bonding is adequate for interconnection - simple - low loss (0.1dB/bonding) $\blacksquare$ Characteristics of MMIC module - Gain difference (${\Delta}S21$) : 0.4 dB

• BMB Reports
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• v.44 no.4
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• pp.267-272
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• 2011

ZAS3 is a large zinc finger transcription repressor that binds the ${\kappa}B$-motif via two signature domains of ZASN and ZASC. A loss-of-function study showed that lack of ZAS3 protein induced accelerated cell proliferation and tumorigenesis. Conversely, gain-of-function studies showed that ZAS3 repressed $NF{\kappa}B$-activated transcription by competing with $NF{\kappa}B$ for the ${\kappa}B$-motif. Based on these observations, we hypothesize that ZAS3 promotes apoptosis by interrupting anti-apoptotic activity of $NF{\kappa}B$. Here, we present evidence that upon $TNF{\alpha}$ stimulation, ZAS3 inhibits $NF{\kappa}B$-mediated cell survival and promotes caspase-mediated apoptosis. The inhibitory effect of ZAS3 on $NF{\kappa}B$ activity is mediated by neither direct association with $NF{\kappa}B$ nor disrupting nuclear localization of $NF{\kappa}B$. Instead, ZAS3 repressed the expression of two key anti-apoptotic genes of $NF{\kappa}B$, TRAF1 and TRAF2, thereby sensitizing cells to $TNF{\alpha}$-induced cell death. Taken together, our data suggest that ZAS3 is a tumor suppressor gene and therefore serves as a novel therapeutic target for developing anti-cancer drugs.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.2
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• pp.267-272
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• 2017

In this paper, we suggested that a RF-front module of down-converter that represents the lowest noise figure to receive high quality video signals because the attenuation occurs in the atmosphere over 20GHz. By budget analysis of CDR, SFDR and CIP3 of RF-FEM, we also analyzed the parameters and linearity that presents high dynamic range. The total gain of designed Ka-band down-converter is 61.8dBand noise figure is 1.05dB, so gain and noise figures show excellent properties. In the future, the designed RF-FEM will be applied to the Ka-band satellite down-converter for UHD-class video transmission.

• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.267-271
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• 2013

A survey of aflatoxin $B_1$ and ochratoxin A was conducted on dried red pepper and red pepper powder. Total number of 193 samples were collected from local markets in Incheon. The presence of aflatoxin $B_1$ and ochratoxin A was determined by high performance liquid chromatography (HPLC) with fluorescence detector using immunoaffinity column clean-up. The recovery rate of aflatoxin $B_1$ and ochratoxin A were more than 80% and the limits of quantification were 0.13 ${\mu}g/kg$ for aflatoxin $B_1$ and 0.30 ${\mu}g/kg$ for ochratoxin A. Aflatoxin $B_1$ was detected in 33 samples (17.1%) with a range of 0.14~9.67 ${\mu}g/kg$ and ochratoxin A was detected in 40 samples (20.7%) with a range of 0.31~3.31 ${\mu}g/kg$. These results show that the occurrence of aflatoxin $B_1$ and ochratoxin A in dried red pepper and red pepper powder tested in this study is low compared with the standard in Korea Food Code (10 ${\mu}g/kg$ as aflatoxin $B_1$ and 7 ${\mu}g/kg$ as ochratoxin A).