• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1344-1352
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• 2007

An opportunistic human pathogen, Pseudomonas aeruginosa, contains the major catalase KatA, which is required to cope with oxidative and osmotic stresses. As an attempt to uncover the $H_2O_2$-dependent regulatory mechanism delineating katA gene expression, four prototrophic $H_2O_2$-sensitive mutants were isolated from about 1,500 TnphoA mutant clones of P. aeruginosa strain PA14. Arbitrary PCR and direct cloning of the transposon insertion sites revealed that one insertion is located within the katA coding region and two are within the coding region of oxyR, which is responsible for transcriptional activation of several antioxidant enzyme genes in response to oxidative challenges. The fourth insertion was within PA3815 (IscR), which encodes a homolog of the Escherichia coli iron-sulfur assembly regulator, IscR. The levels of catalase and SOD activities were significantly reduced in the iscR mutant, but not in the oxyR mutant, during the normal planktonic culture conditions. These results suggest that both IscR and OxyR are required for the optimal resistance to $H_2O_2$, which involves the expression of multiple antioxidant enzymes including KatA.

• Korean Journal of Animal Reproduction
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• v.22 no.2
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• pp.127-136
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• 1998

A chimeric gene comprising murine whey acidic protein(mWAP) and human growth hormone(hGH) was used to produce transgenic rats express hGH and secrete it into the blood. Two lines of transgenic rats carrying the mWAP/hGH construct were established; High line was characterized by relatively high levels of serum hGH, and low line had relatively low levels. The secretory profiles of rat GH(rGH) as well as hGH, the transgene product, were obtained in transgenic males and females of low line; both hGH and rGH serum levels were flattened with no episodic fluctuations, and the overall mean concentration of rGH was significantly lower than in normal littermates. Although the animals of High line showed an acceles, as assessed by vaginal opening and occurrence of first ovulation, advanced by 7∼8 days in both lines of animals. Accordingly, the body weight at puberty of low line transgenic females was much lower than that of normal littermates, indicating that continuous hGH expression could induce precocious puberty without enhancing the growth rate.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.203-209
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• 2008

The aim of this study was to investigate the hepatoprotective effect of $ACTIValoe^{(R)}$ N-931 complex, a mixture of Aloe vera and Silybum marianum, against acute liver injuries. Acute liver damages were induced by intraperitoneal injection of galactosamine (GalN, 700 mg/kg), naphthylisothiocyanate (ANIT, 40 mg/kg) and ethionine (500 mg/kg). $ACTIValoe^{(R)}$ N-931 (85, 170 and 340) was administered orally 48 h, 24 h, 2 h before and 6 h after the injection of hepatotoxins. At 24 h after GalN treatment the levels of serum aminotransferases and hepatic lipid peroxidation were significantly elevated, whereas hepatic glutathione, serum triglyceride (TG) and total cholesterol were decreased. These changes were attenuated by $ACTIValoe^{(R)}$ N-931 complex. The serum aminotransferase activities and total bilirubin significantly increased at 48 h after ANIT treatment, but were attenuated by $ACTIValoe^{(R)}$ N-931 complex. The bile flow was lower after ANIT treatment, which was restored by $ACTIValoe^{(R)}$ N-931 complex. $ACTIValoe^{(R)}$ N-931 complex reduced the ethionine-induced elevated hepatic TG contents. Histopathological analysis revealed that signs of liver injury were prominent at 24 h as result of ethionine injection, demonstrated by extensive areas of fatty change and microvesicular steatosis were observed around cells. These changes were attenuated by $ACTIValoe^{(R)}$ N-931 complex. Our results suggest that the $ACTIValoe^{(R)}$ N-931 complex has a protective effect on acute liver injury.

• Journal of Ginseng Research
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• v.40 no.2
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• pp.151-159
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• 2016

Background: Ginsenoside-Rg3, the pharmacologically active component of red ginseng, has been found to inhibit tumor growth, invasion, metastasis, and angiogenesis in various cancer models. Previously, we found that 20(R)-ginsenoside-Rg3 (Rg3) could inhibit angiogenesis. Since microRNAs (miRNAs) have been shown to affect many biological processes, they might play an important role in ginsenoside-mediated angiomodulation. Methods: In this study, we examined the underlying mechanisms of Rg3-induced angiosuppression through modulating the miRNA expression. In the miRNA-expression profiling analysis, six miRNAs and three miRNAs were found to be up- or down-regulated in vascular-endothelial-growth-factor-induced human-umbilical-vein endothelial cells (HUVECs) after Rg3 treatment, respectively. Results: A computational prediction suggested that mature hsa-miR-520h (miR-520h) targets ephrin receptor (Eph) B2 and EphB4, and hence, affecting angiogenesis. The up-regulation of miR-520h after Rg3 treatment was validated by quantitative real-time polymerase chain reaction, while the protein expressions of EphB2 and EphB4 were found to decrease, respectively. The mimics and inhibitors of miR- 520h were transfected into HUVECs and injected into zebra-fish embryos. The results showed that overexpression of miR-520h could significantly suppress the EphB2 and EphB4 protein expression, proliferation, and tubulogenesis of HUVECs, and the subintestinal-vessel formation of the zebra fish. Conclusion: These results might provide further information on the mechanism of Rg3-induced angiosuppression and the involvement of miRNAs in angiogenesis.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.5
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• pp.325-333
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• 2022

Heart failure (HF) has become one of the severe public health problems. The detailed role of mitochondrial function in HF was still unclear. Benzoylaconine (BAC) is a traditional Chinese medicine, but its role in HF still needs to be explored. In this study, oxygen-glucose deprivation and reperfusion (OGD/R) was executed to mimic the injury of H9C2 cells in HF. The viability of H9C2 cells was assessed via MTT assay. OGD/R treatment markedly decreased the viability of H9C2 cells, but BAC treatment evidently increased the viability of OGD/R-treated H9C2 cells. The apoptosis of H9C2 was enhanced by OGD/R treatment but suppressed by BAC treatment. The mitochondrial membrane potential was evaluated via JC-1 assay. BAC improved the mitochondrial function and suppressed oxidative stress in OGD/R-treated H9C2 cells. Moreover, Western blot analysis revealed that the protein expression of p-AMPK and PGC-1α were reduced in OGD/R-treated H9C2 cells, which was reversed by BAC. Rescue assays indicated that AMPK attenuation reversed the BAC-mediated protective effect on OGD/R-treated cardiomyocytes. Moreover, BAC alleviated myocardial injury in vivo. In a word, BAC modulated the mitochondrial function in OGD/R-induced cardiomyocyte injury by activation of the AMPK/PGC-1 axis. The findings might provide support for the application of BAC in the treatment of HF.

• Bulletin of the Korean Mathematical Society
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• v.50 no.4
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• pp.1235-1242
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• 2013

We give area and height estimates for cmc-graphs over a bounded planar $C^{2,{\alpha}}$ domain ${\Omega}{\subset}\mathbb{R}^3$. For a constant H satisfying $H^2{\mid}{\Omega}{\mid}{\leq}9{\pi}/16$, we show that the height $h$ of H-graphs over ${\Omega}$ with vanishing boundary satisfies ${\mid}h{\mid}$ < $(\tilde{r}/2{\pi})H{\mid}{\Omega}{\mid}$, where $\tilde{r}$ is the middle zero of $(x-1)(H^2{\mid}{\Omega}{\mid}(x+2)^2-9{\pi}(x-1))$. We use this height estimate to prove the following existence result for cmc H-graphs: for a constant H satisfying $H^2{\mid}{\Omega}{\mid}$ < $(\sqrt{297}-13){\pi}/8$, there exists an H-graph with vanishing boundary.

• Journal of the Korean Mathematical Society
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• v.34 no.2
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• pp.345-370
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• 1997

In this paper, we introduce the Fock representation $U^{F, M}$ of the Heisenberg group $H_R^(g, h)$ associated with a positive definite symmetric half-integral matrix $M$ of degree h and prove that $U^{F, M}$ is unitarily equivalent to the Schrodinger representation of index $M$.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2002.11a
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• pp.105.2-106
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• 2002

• Korean Journal of Mineralogy and Petrology
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• v.33 no.2
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• pp.99-114
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• 2020

The characteristics of the Brazilian tensile strengths(σ_t) parallel to the rock cleavages in Jurassic granite from Geochang were analysed. The evaluation for the six directions of rock cleavages was performed using the parameter values on microcrack length and the above strength. The strength values of the five test specimens belonging to each direction were classified into five groups. The strength values of these five groups increase in order of group A < B < C < D < E. The close dependence between the above microcrack and strength was derived. The analysis results of this study are summarized as follows. First, the chart showing the variation and characteristics of strength among the three rock cleavages were made. In the above chart, the strength values of six directions belonging to each group were arranged in order of rift(R1 and R2), grain(G1 and G2) and hardway(H1 and H2). The strength distribution lines of the five groups concentrate in the direction of R1. And the widths among the above five lines indicating strength difference(Δσ_t) are the most narrowest in R1 direction. From the related chart, the variation characteristics among the two directions forming each rock cleavage were derived. G2(2)-test specimen shows higher value and lower value of the difference in strength compared to the case of G1(1)-test specimen. These kinds of phenomena are the same as the case between the test specimen H2(2) and H1(1). The strength characteristics of the above test specimens (2) suggest lower microcrack density value and higher degree of uniformity in the distribution of microcracks arrayed parallel to the loading direction compared to those of test specimens (1). The six strength values belonging to each group were arranged in increasing order in the above chart. The strength values of the test specimens belonging to both group D and E appear in order of R1 < R2 < G1 < H1 < G2 < H2. Therefore, the strength values of group D and E can be indicator values for evaluating the six directions of rock cleavages. Second, the correlation chart between slope angle(θ) and strength difference(Δσ_t) were made. The values of the above two parameters were obtained from the five strength distribution lines connecting between the two directions. From the chart related to rift plane(G1-H1, R'), grain plane(R1-H2, G') and hardway plane(R2-G2, H'), the slope values of linear functions increase in order of R'(0.391) < G'(0.470) < H'(0.485). Among three planes, the charts related to hardway plane show the highest distribution density among the five groups. From the related chart for rift(R1-R2, R), grain(G1-G2, G) and hardway(H1-H2, H), the slope values of linear functions increase in order of rift(0.407) < hardway(0.453) < grain(0.460). Among three rock cleavages, the charts related to rift show the highest frequency of groups belonging to the lower region. Taken together, the width of distribution of the slope angle among the three planes and three rock cleavages increase in order of H' < G < R' < R < G' < H. Third, the correlation analysis among the parameters related to microcrack length and the tensile strengths was performed. These parameters may include frequency(N), total length(Lt), mean length(Lm), median length(Lmed) and density(ρ). The correlation charts among individual parameters on the above microcrack(X) and corresponding five levels of tensile strengths for the five groups(Y) were made. From the five kinds of correlation charts, the values of correlation coefficients(R²) increase along with the five levels of strengths. The mean values of the five correlation coefficients from each chart increase in order of 0.22(N) < 0.34(Lt) < 0.38(ρ) < 0.57(Lmed) < 0.58(Lm). Fourth, the correlation chart among the corresponding maximum strength for group E(X) and the above five parameters(Y) were made. From the related chart, the values of correlation coefficient increase in order of 0.61(N) < 0.81(Lt) < 0.87(ρ) < 0.93(Lm) < 0.96(Lmed). The two parameters that have the highest correlations are median length with maximum strength. Through the above correlation analysis between microcrack and strength, the credibility for the results from this study can be enhanced.

• Bulletin of the Korean Mathematical Society
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• v.54 no.6
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• pp.1969-1980
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• 2017

Let ${\Gamma}$ be a nonzero torsionless commutative cancellative monoid with quotient group ${\langle}{\Gamma}{\rangle}$, $R={\bigoplus}_{{\alpha}{\in}{\Gamma}}R_{\alpha}$ be a graded integral domain graded by ${\Gamma}$ such that $R_{{\alpha}}{\neq}\{0\}$ for all ${\alpha}{\in}{\Gamma},H$ be the set of nonzero homogeneous elements of R, C(f) be the ideal of R generated by the homogeneous components of $f{\in}R$, and $N(H)=\{f{\in}R{\mid}C(f)_v=R\}$. In this paper, we introduce the notion of graded t-almost Dedekind domains. We then show that R is a t-almost Dedekind domain if and only if R is a graded t-almost Dedekind domain and RH is a t-almost Dedekind domains. We also show that if $R=D[{\Gamma}]$ is the monoid domain of ${\Gamma}$ over an integral domain D, then R is a graded t-almost Dedekind domain if and only if D and ${\Gamma}$ are t-almost Dedekind, if and only if $R_{N(H)}$ is an almost Dedekind domain. In particular, if ${\langle}{\Gamma}{\rangle}$ isatisfies the ascending chain condition on its cyclic subgroups, then $R=D[{\Gamma}]$ is a t-almost Dedekind domain if and only if R is a graded t-almost Dedekind domain.