• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.263-266
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• 2002

In this paper, It is indicating that an issues of the conventional boost converter for high frequency induction heating. To improve those issues, it is proposed, simulated and analyzed that the current resonant circuit, simulated. As the result, we knew that the proposed circuit has a good point to improve the waveform of input current and to make high efficiency. On the other side, in the inverter for the high current power supply, it is proposed that the high frequency inverter of the half bridge topology, be done the circuit analysis to extract the optimal circuit parameter. It is making sure of the soft switching operating by the inductor to reverse parallel connected on the inverter main switch, decreasing the surge voltage when the switch is turn-off by compulsion, and repressing the switch current and bringing the high current amplitude operation by the multi resonance.

• Journal of Microbiology and Biotechnology
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• v.21 no.3
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• pp.243-251
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• 2011

The gene bolA was discovered in the 80's, but unraveling its function in the cell has proven to be a complex task. The BolA protein has pleiotropic effects over cell physiology, altering growth and morphology, inducing biofilm formation, and regulating the balance of several membrane proteins. Recently, BolA was shown to be a transcription factor by repressing the expression of the mreB gene. The present report shows that BolA is a transcriptional regulator of the dacA and dacC genes, thus regulating both DD-carboxypeptidases PBP5 and PBP6 and thereby demonstrating the versatility of BolA as a cellular regulator. In this work, we also demonstrate that reduction of cell growth and survival can be connected to the overexpression of the bolA gene in different E. coli backgrounds, particularly in the exponential growth phase. The most interesting finding is that overproduction of BolA affects bacterial growth differently depending on whether the cells were inoculated directly from a plate culture or from an overnight batch culture. This strengthens the idea that BolA can be engaged in the coordination of genes that adapt the cell physiology in order to enhance cell adaptation and survival under stress conditions.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.80-80
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• 2018

Chlorogenic acid is a phenolic compound found in Cudrania tricuspidata fruits. In the present study, the effect of chlorogenic acid on the inhibition of adipogenesis in 3T3-L1 adipocytes was investigated. Cells were stained with Oil red O reagent to detect lipid droplets in adipocytes. The 3T3-L1 cells were lysed and measured for intracellular triglyceride and adipokine by ELISA kit. The protein expression of adipogenesis-related gene was evaluated by Western blot analysis. Chlorogenic suppressed lipid droplet and intracellular triglyceride accumulation in a concentration manner and also decreased secretion of adipokines such as leptin and adiponectin, compared with fully differentiated adipocytes. Treatment of 3T3-L1 cells with chlorogenic acid reduced the protein levels of peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) and, CCAAT/enhancer binding proteins alpha ($C/EBP{\alpha}$). This indicates that chlrogenic acid was effective as an anti-obesity agent by repressing the differentiation of 3T3-L1 into adipocytes and inhibiting triglyceridef formation in adipocyte and that it exerts its role mainly through the significant down-regulation of $PPAR{\gamma}$ and $C/EBP{\alpha}$.

• BMB Reports
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• v.46 no.4
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• pp.219-224
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• 2013

The cell-fate specification of the anchor cell (AC) and a ventral uterine precursor cell (VU) in Caenorhabditis elegans is initiated by a stochastic interaction between LIN-12/Notch receptor and LAG-2/Delta ligand in two neighboring Z1.ppp and Z4.aaa cells. Both cells express lin-12 and lag-2 before specification, and a small difference in LIN-12 activity leads to the exclusive expressions of lin-12 in VU and lag-2 in the AC, through a feedback mechanism of unknown nature. Here we show that the expression pattern of lag-1/CSL, a transcriptional repressor itself that turns into an activator upon binding of the intracellular domain of Notch, overlaps with that of lin-12. Site-directed mutagenesis of LAG-1 binding sites in lag-1 maintains its expression in the AC, and eliminates it in the VU. Thus, AC/VU cell-fate specification appears to involve direct regulation of lag-1 expression by the LAG-1 protein, activating its transcription in VU cells, but repressing it in the AC.

• Journal of Sasang Constitutional Medicine
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• v.4 no.1
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• pp.231-240
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• 1992

In order to investigate experimentally the effects of Taeumin Handayolsot'ang and Gamihandayolsot'ang, experimental studies were conducted about antipyretic effect, analgesic effect, antiinflammatory effect of edema, sadative effect, anticonvulsive effect experimental animals (mice and rats). Sample A group was a solid extract of Handayolsot'ang treated group. Sample B group was a solid extract of Gamihandayolsot'ang treated group. The results were summarized as fallows. 1. In antipyretic action by yeast method, sample A group was decreased significantly and sample B group showed decreasing tendency, but showed no significance. 2. In the effect of control for writhing syndrome by the acetic acid stimulating method, sample B group was repressed significantly and sample A group showed repressing tendency, but showed no significance. 3. Antiinflammatory action by carrageenine edema method was showed significant effect at all sample groups. 4. Sadative effect by rotor rod method in rats was not noted at all sample groups. 5. In anticonvulsive action by E C T unit method, time to death in mice was significantly prolonged at all sample groups. According to the above results, it is considered that Taeumin Handayolsot'ang and Gamihandayolsot'ang will be effective on pyretic diseases.

• The Korean Journal of Ecology
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• v.21 no.5_3
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• pp.603-631
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• 1998

Flora and distribution of vascular plants included introduced species of Mt. Nam park in Seoul were investigated from 1997 to 1998. The flora was composed of 112 families, 338 genera, 487 species, 1 subspecies, 60 varieties, 11 forma or 559 taca. Whole taxa of Mt. Nam calculated with the other reports were recorded 125 families, 461 genera, 832 species, 2 subspecies, 115 varieties, 14 forma or 963 taxa. Mt. nam area has lost its properties because of road and promenade construction, several park reclaimation, introduction of foreign species and exotic plants, and so on. The urbanized index (UI) was comparatively high at 18.3%. Eupatorium rugosum which shown high shade tolerance comparatively was occupied dominantly in road sides. The natural ecosystem and biodiversity of Mt. Nam were under threatened by introduced species. DBH mode of Pinus densiflora community was shown bell shape but that of Quercus mongolica was shown reverse J shape, therefore, it will be occupied in the future this area dominantly by Q. mongolica community. However the vegetation of Mt. nam park area are repressing by superior position in their growth of introduced species included R. pseudo-acacia, Ailanthus altissima and E. rugosum, etc.

• BMB Reports
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• v.54 no.8
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• pp.413-418
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• 2021

ErbB3-binding protein 1 (EBP1) is a multifunctional protein associated with neural development. Loss of Ebp1 leads to upregulation of the gene silencing unit suppressor of variegation 3-9 homolog 1 (Suv39H1)/DNA (cytosine 5)-methyltransferase (DNMT1). EBP1 directly binds to the promoter region of DNMT1, repressing DNA methylation, and hence, promoting neural development. In the current study, we showed that EBP1 suppresses histone methyltransferase activity of Suv39H1 by promoting ubiquitin-proteasome system (UPS)-dependent degradation of Suv39H1. In addition, we showed that EBP1 directly interacts with Suv39H1, and this interaction is required for recruiting the E3 ligase MDM2 for Suv39H1 degradation. Thus, our findings suggest that EBP1 regulates UPS-dependent degradation of Suv39H1 to govern proper heterochromatin assembly during neural development.

• Molecules and Cells
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• v.45 no.9
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• pp.631-639
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• 2022

Breast cancer is the leading cause of cancer-related death in women worldwide, despite medical and technological advancements. The RhoBTB family consists of three isoforms: RhoBTB1, RhoBTB2, and RhoBTB3. RhoBTB1 and RhoBTB2 have been proposed as tumor suppressors in breast cancer. However, the roles of RhoBTB3 proteins are unknown in breast cancer. Bioinformatics analysis, including Oncomine, cBioportal, was used to evaluate the potential functions and prognostic values of RhoBTB3 and Col1a1 in breast cancer. qRT-PCR analysis and immunoblotting assay were performed to investigate relevant expression. Functional experiments including proliferation assay, invasion assay, and flow cytometry assay were conducted to determine the role of RhoBTB3 and Col1a1 in breast cancer cells. RhoBTB3 mRNA levels were significantly up-regulated in breast cancer tissues as compared to in adjacent normal tissues. Moreover, RhoBTB3 expression was found to be associated with Col1a1 expression. Decreasing RhoBTB3 expression may lead to decreases in the proliferative and invasive properties of breast cancer cells. Further, Col1a1 knockdown in breast cancer cells limited the proliferative and invasive ability of cancer cells. Knockdown of RhoBTB3 may exert inhibit the proliferation, migration, and metastasis of breast cancer cells by repressing the expression of Col1a1, providing a novel therapeutic strategy for treating breast cancer.

• Development and Reproduction
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• v.27 no.1
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• pp.39-46
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• 2023

Pumilio (Pum) is an RNA-binding protein and translational repressor important to diverse biological processes. In the Drosophila ovary, Pum is expressed in female germline stem cells (GSCs), wherein it acts as an intrinsic stem cell maintenance factor via repressing target mRNAs that are as yet mostly unknown. Pum recognizes the Pum binding sequence (PBS) in the mRNA 3'UTR through its C-terminus Puf domain. Translational repression is mediated through its N-terminal domain, but the molecular mechanism remains largely unknown. We previously showed that Bag-of-marbles, a critical differentiation-promoting factor of female GSCs, physically interacts with the N-terminus of Pum. We further showed that this interaction is critical to Bam inhibition of Pum repressive action in cultured cells, but the physiological relevance was not addressed. Here we design an in vivo GFP translational reporter bearing the PBS in its 3'UTR and show that GFP expression is reduced in cells wherein Pum is known to be active. Furthermore, we demonstrate in pum mutant ovary that this GFP repression requires Pum, and also that the sensor faithfully monitors Pum activity. Finally, we show that forced expression of Bam inhibits Pum-mediated repression, validating that Bam inhibits Pum activity in vivo.

• Journal of Microbiology
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• v.45 no.6
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• pp.558-565
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• 2007

Using microarray analysis, we determined those Salmonella genes induced at the entry of stationary phase, and subsequently discovered that uncharacterized yliH was induced most dramatically. We set out to establish the molecular mechanism underlying the stationary phase induction of yliH under the standard culture condition, LB with vigorous aeration, by analyzing its promoter activity in various mutant backgrounds, lacking stationary phase ${\sigma}$, $RpoS^-$, or stringent signal molecules ppGpp, ${\Delta}relA$ ${\Delta}spoT$. It was found that the stationary phase induction of yliHp was partially dependent on rpoS but entirely dependent on ppGpp. DNA sequence analysis revealed that the Salmonella yliH gene is composed of 381 base-pair nucleotides, with overall amino acid sequence revealing 76.38% amino acid identity and 88.98% similarity with Escherichia coli yliH, although no motif from data base was noted for its possible role. Recently however, it has been reported that yliH in E. coli was implicated in biofilm formation and motility by repressing these activities (Domka et al., 2006). We have constructed a mutant Salmonella deleting yliH gene by allele replacement and examined its phenotype, and found that the yliH in Salmonella more or less affects motility and adherence by enhancing these activities. The effect on biofilm formation in Salmonella was uncertain. Moreover, addition of cloned yliH of E. coli into Salmonella did not reduce motility or adherence. Taken together, it appears that the pathways implicating yliH for biofilm formation and motility in E. coli and in Salmonella are somewhat different.