• Journal of Microbiology and Biotechnology
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• v.22 no.4
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• pp.479-483
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• 2012

The secretory efficiency of recombinant xylanase xynB from yeast Pichia pastoris between the ${\alpha}$-factor preprosequence and a classical mammalian signal peptide derived from bovine ${\beta}$-casein was compared. The results showed that although the bovine ${\beta}$-casein signal peptide could direct high-level secretion of recombinant xylanase, it was relatively less efficient than the ${\alpha}$-factor preprosequence. In contrast, the bovine ${\beta}$-casein signal peptide caused remarkably more recombinant xylanase trapped intracellularly. Real-time RT-PCR analysis indicated that the difference in the secretory level between the two signal sequences was not due to the difference in the transcriptional efficiency.

• BMB Reports
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• v.29 no.3
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• pp.241-247
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• 1996

The Philadelphia (Ph) chromosome is the single most intensively studied chromosome alteration characterizing a human malignancy. The specific genetic alteration of chronic myelogenous leukemia (CML) is the formation of the BCR/abl fusion gene in leukemic cells. The presence of the BCR/abl gene has important diagnostic and prognostic implications in CML. The detection of BCR/abl transcripts by reverse transcriptase based polymerase chain reaction (RT-PCR) was investigated in patients with CML in whom the Ph chromosome abnormality was documented by cytogenetic analysis. In a total of 68 CML patient cases, the Ph chromosome was found in 53 cases (77.9%) by cytogenetic analysis. On the other hand, sixty two cases (91.2%) were detected to have BCR/abl gene rearrangement Of these, b3a2 was 44 cases (64.7%) and b2a2 was 17 cases (25,0%). There was one case with both b3a2 and b2a2 (1.5%). Of the fifteen cases of Ph chromosome negative by cytogenetic anlaysis, the BCR/abl gene was observed in nine cases, The results of BCR/abl fusion gene confirmed by the direct sequencing method correlated well with PCR analysis, The amplified PCR products were detected by $1{\times}10^{-5}$ dilutions. In conclusion, PCR technique is sensitive, rapid and relatively simple for a laboratory test in detecting the BCR/abl fusion gene with CML regardless of the result of cytogenetic analysis.

• Korean Journal of Food Science and Technology
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• v.53 no.1
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• pp.1-11
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• 2021

In this review, recent foodborne outbreaks caused by viruses in the Republic of Korea (2010-2019) were analyzed. The human norovirus was found to be the major foodborne virus causing an average of 94.9% of the viral outbreaks. Reverse-transcription polymerase chain reaction (PCR) with electrophoresis has been widely used to detect viruses, but several rapid detection methods, including real-time PCR, multiplex PCR, and quantum dot assay, have also been suggested. For norovirus inactivation studies, surrogates such as murine norovirus and feline calicivirus have been widely used to identify the reduction rate owing to the limitations in laboratory cultivation. Conversely, direct cell infection studies have been conducted for other foodborne viruses such as adenovirus, astrovirus, rotavirus, and hepatitis A or E virus. Moreover, virucidal mechanisms using various physical and chemical treatments have been revealed. These recent studies suggest that rapid in situ detection and effective control are valuable for ensuring food safety against viral infections.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.5
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• pp.1330-1334
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• 2003

Astragali Radix(AR), one of the strong tonic herbs, is known to improve immunological responses in mice and human. In this study, AR's ai-reinforcing effect was examined in the context of CD4/sup +/ T cells' TCR/CD3 induced activation responses. In order to evaluate the direct effect of AR on helper T cells, CD4/sup +/ T cells are isolated using magnetic bead and their proliferation and CD69 expression in AR treated medium were assessed with anti-CD3/anti-CD28 activation for 48h. CD4 T cells' proliferation was slightly increased but there was little effect on CD69 expression. RT PCR and ELISA equally demonstrated that IL-2 and IL-4 production was increased but IFN-ν was down-regulated. This shows AR ethanol extract favors Th2 cytokine profile under neutral conditions.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1377-1383
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• 2005

In a cDNA microarray experiment using Cy3 and Cy5 as labeling agents, particularly for the direct design, cDNAs from some genes incorporate one dye more efficiently than the other, which is referred to as the gene-specific dye bias. Dye-swaps, in which two dyes are switched on replicate arrays, are commonly used to control the gene-specific dye bias. We developed a simple procedure to extract the gene-specific dye bias information from a partial dye swap experiment. We detected gene-specific dye bias by identifying outliers in an X-Y plane, where the X axis represents the average log-ratio from two sets of dye swap pairs and the Y axis exhibits the average log ratio of four forward labeled arrays. We used this information for detecting differentially expressed genes, of which the additionally detected genes were validated by real-time RT-PCR.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.114-114
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• 2003

Ginseng is a medicinal herb widely used in Asian countries, and its pharmacological effects has been demonstrated in various systems such as cardiovascular, central nervous, and endocrine systems. Its effects are mainly attributed to the ginsenosides. We hypothesize that a component of Panax ginseng, ginsenoside-Rbl, acts by binding to estrogen receptor. We have investigated the estrogenic activity of ginsenoside-Rbl in a transient transfection system using estrogen receptors ${\alpha}$ or ${\beta}$ with estrogen -responsive luciferase plasmids in COS monkey kidney cells. Ginsenoside-Rbl activated both estrogen receptors ${\alpha}$ and ${\beta}$ in a dose-dependent manner (0.5 -100 M ). Activation was inhibited by the specific estrogen receptor antagonist ICI 182,780, indicating that the estrogenic effect of ginsenoside-Rbl is estrogen receptor dependent. Next, we evaluated the ability of ginsenoside-Rbl to induce estrogen-responsive progesterone receptor gene by semi-quantitative RT-PCR assays. MCF-7 cells treated with l7${\beta}$-estradiol or ginsenoside- Rb1 exhibited an increased expression of progesterone receptor mRNA. However, ginsenoside-Rbl failed to displace the specific binding of ［3H］17${\beta}$-estradiol to estrogen receptor in MCF-7 cells as examined by whole cell ligand binding assays, suggesting that there is no direct interaction of ginsenoside-Rbl with estrogen receptor. Our results indicate that estrogen-like activity of ginsenoside-Rbl is independent of direct estrogen receptor association.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4671-4676
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• 2014

Background: MicroRNA-200a (miR-200a) has been reported to regulate tumour progression in several tumours but little is known about its role in neuroblastoma. Our aim was to investigate the potential role and mechanism of miR-200a in neuroblastomas. Materials and Methods: Expression levels of miR-200a in tissues were determined using RT-PCR. The effect of miR-200a and shAP-$2{\gamma}$ on cell viability was evaluated using MTS assays, and target protein expression was determined using Western blotting and RT-PCR. Luciferase reporter plasmids were constructed to confirm direct targeting. Results were reported as mean${\pm}$S.E.M and differences were tested for significance using the 2-tailed Students t-test. Results: We determined that miR-200a expression was significantly lower in neuroblastoma tumors than the adjacent non-cancer tissue. Over-expression of miR-200 are reduced cell viability in neuroblastoma cells and inhibited tumor growth in mouse xenografts. We identified AP-$2{\gamma}$ as a novel target for miR-200a in neuroblastoma cells. Thus miR-200a targets the 3'UTR of AP-$2{\gamma}$ and inhibits its mRNA and protein expression. Furthermore, our result showed that shRNA knockdown of AP-$2{\gamma}$ in neuroblastoma cells results in significant inhibit of cell proliferation and tumor growth in vitro, supporting an oncogenic role of AP-$2{\gamma}$ in neuroblastoma. Conclusions: Our study revealed that miR-200a is a candidate tumor suppressor in neuroblastoma, through direct targeting of AP-$2{\gamma}$. These findings re-enforce the proposal of AP-$2{\gamma}$ as a therapeutic target in neuroblastoma.

• Research in Plant Disease
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• v.22 no.1
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• pp.59-63
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• 2016

A new poty-like virus was isolated from plants of winter daphne (Daphne odora) that showed virus-like symptoms on leaves, from four regions of Korea during 2014. Filamentous-shaped particles were observed by transmission electron microscopy of preparations extracted from symptomatic leaves and examined by the direct negative stain method. RT-PCR assay showed that three samples were positive for both Cucumber mosaic virus and potyvirus, and only one sample was positive for potyvirus only. A BLAST comparison to partial sequences from helper-component proteinase, cylindrical inclusion and coat protein genes detected the highest nucleotide identity of 76%, 72%, and 72% with Daphne mosaic virus, respectively, levels below the potyvirus species discrimination threshold. The new potyvirus was isolated using indicator plants (Chenopodium amaranticolor), in which local lesions were produced. In this study, we identified a novel potyvirus from winter daphne, which we have named Daphne mottle virus (DapMoV).

• The Plant Pathology Journal
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• v.23 no.4
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• pp.260-265
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• 2007

Testing a large number of samples from field monitoring and routine indexing is cumbersome and the available virus detection tools were labor intensive and expensive. To circumvent these problems we established tissue blot immunoassay (TBIA) method an alternative detection tool to detect Barley mild mosaic virus (BaMMV) and Barley yellow mosaic virus (BaYMV) infection in the field and greenhouse inoculated plants for monitoring and routine indexing applications, respectively. Initially, leaf and stem were tested to determine suitable plant tissue for direct blotting on nitrocellulose membrane. The dilutions of antibodies were optimized for more efficient and economical purposes. Results showed that stem tissue was more suitable for direct blotting for it had no background that interferes in the reaction. Therefore, this technique was referred as direct stem blot immunoassay or DSBIA, in this study. Re-used diluted (1:1000) antiserum and conjugate up to 3 times with the addition of half strength amount of concentrated antibodies was more effective in detecting the virus. The virus blotted on the nitrocellulose membrane from stem tissues kept at room temperature for 3 days were still detectable. The efficiency of DSBIA and RT-PCR in detecting BaMMV and BaYMV were relatively comparable. Results further proved that DSBIA is a rapid, reliable and economical detection method suitable for monitoring BaMMV and BaYMV infection in the field and practical method in indexing large scale of barley materials for virus resistance screening.

• BMB Reports
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• v.51 no.11
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• pp.602-607
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• 2018

Aberrant expression of microRNAs (miRNAs) plays important roles in carcinogenesis and tumor progression. However, the expression and biological role of miR-301b in triple-negative breast cancer (TNBC) remains unclear. Here we aimed to evaluate the roles and mechanisms of miR-301b in TNBC cells. miR-301b expression was assessed in TNBC specimens and cell lines by quantitative Real-Time PCR (qRT-PCR). TNBC cells were transfected with miR-301b mimics, inhibitors or Cylindromatosis (CYLD) small interfering RNA (siRNA) using Lipofectamine 2000. The functional roles of miR-301b were determined by cell proliferation, colony formation, and apoptosis assays. Western blots and qRT-PCR were used to measure the expression of mRNAs and proteins in the cells. We found that miR-301b was upregulated in TNBC specimens and cell lines. Overexpression of miR-301b promoted cell proliferation in TNBC cells, while inhibited the apoptosis induced by 5-FU. CYLD was downregulated by miR-301b at both mRNA and protein levels in TNBC cells. Dual-luciferase report assay confirmed that miR-301b downregulated CYLD by direct interaction with the 3'-untranslated region(3'-UTR) of CYLD mRNA. $NF-{\kappa}B$ activation was mechanistically associated with miR-301b-mediated downregulation of CYLD. However, inhibition of miR-301b reversed all the effects of miR-301b. In conclusion, miR-301b plays an oncogenic role in TNBC possibly by downregulating CYLD and subsequently activating $NF-{\kappa}B$ p65, and this may provide a novel therapeutic approach for TNBC.