• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2753-2758
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• 2014

Background: GC-binding factor 2 (GCF2) is a transcriptional regulator that represses transcriptional activity of the epidermal growth factor receptor (EGFR) by binding to a specific GC-rich sequence in the EGFR gene promoter. In addition to this function, GCF2 has also been identified as a tumor-associated antigen and regarded as a potentially valuable serum biomarker for early human hepatocellular carcinoma (HCC) diagnosis. GCF2 is high expressed in most HCC tissues and cell lines including HepG2. This study focused on the influence of GCF2 on cell proliferation and apoptosis in HepG2 cells. Materials and Methods: GCF2 expression at both mRNA and protein levels in HepG2 cells was detected with reverse transcription (RT) PCR and Western blotting, respectively. RNA interference (RNAi) technology was used to knock down GCF2 mRNA and protein expression. Afterwards, cell viability was analyzed with a Cell Counting Kit-8 (CCK-8), and cell apoptosis and caspase 3 activity by flow cytometry and with a Caspase 3 Activity Kit, respectively. Results: Specific down-regulation of GCF2 expression caused cell growth inhibition, and increased apoptosis and caspase 3 activity in HepG2 cells. Conclusions: These primary results suggest that GCF2 may influence cell proliferation and apoptosis in HepG2 cells, and also provides a molecular basis for further investigation into the possible mechanism at proliferation and apoptosis in HCC.

• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.442-448
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• 2013

Lactic acid bacteria (LAB) are a representative group of probiotics and used in many fermented foods and beverages. Several recent studies have shown that LAB are present in makgeolli which is a traditional Korean alcoholic beverage. However, most LAB are intolerant of more than 6% (v/v) alcohol concentrations. For this reason, alcohol-tolerant LAB are isolated from kimchi, makgeolli and nuruk using alcohol containing selective media. After being cultured in MRS broth containing 13% (v/v) alcohol, the two strains which showed the highest increasing O.D values, were finally selected. As results of 16S rRNA gene sequencing and biochemical characterization using an API kit, the two species were identified as Pediococcus acidilactici K3 and S1. In addition, the identified two strains produced bacteriocins against Staphylococcus aureus. When compared with the P. acidilactici type strain, the two selected strains possessed two to three time higher growth on 12-13% (v/v) alcohol containing MRS broth. The viability of P. acidilactici K3 and S1 when inoculated in makgeolli and stored at $10^{\circ}C$ did not decrease through a period of one month indicating that the selected strains can be used for LAB containing makgeolli.

• Korean Journal of Microbiology
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• v.45 no.1
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• pp.32-40
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• 2009

To understand contribution of thermophilic microorganisms in decomposition of litter deposits on shore of lakes, we surveyed a lakeshore litter deposit for bacteria growing at $60^{\circ}C$. Ten thermophilic isolates were selected for in-depth characterization, based on their high capacity to degrade high molecular weight organic compounds. Based on phylogenetic analysis on their 16S rRNA gene sequences, all isolates were identified as Geobacillus. The optimal growth temperature and pH of the strains ranged $55{\sim}60^{\circ}C$ and 6.0${\sim}$8.0, respectively. Salinity was inhibitory to the growth of the isolates, showing marked decrease of growth rates at 3% salinity. Based on activities of hydrolytic enzymes and profiles of carbohydrate utilization (determined by API 50 CHB kit), three G. stearothermophilus strains showed patterns clearly distinctive from other isolates. Two G. kaustophilus strains also demonstrated distinctiveness in their metabolic pattern and ecological parameters. However, ecological and metabolic profiles of the other five isolates were more variable and showed some degree of digression from their phylogenetic classification. Therefore, it could be concluded that endospore-forming thermophilic bacteria in lakeshore litter deposits contribute to degradation of organic materials with diverse ecological niches while having successions similar to microbial flora in compost. We propose that the thermophilic isolates and/or their thermo-tolerant enzymes can be applied to industrial processes as appropriate mixtures.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.3
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• pp.1650-1662
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• 2014

This study aimed to develop smartphone application contents for the medication reconciliation of high-alert medications and to evaluate the satisfaction for this application. The xcode 4.5 and ios 6.1 SDK(software development kit) were used for constructing screen of the system. After implementation during 4 weeks, thirty five ICU(Intensive Care Unit) nurses were asked function related, contents related, and usage related satisfaction using 12 items. And differences of satisfaction according to the number of daily use and the frequency of use were evaluated. Data were analyzed using descriptive analysis, ANOVA with the SPSS 18.0. We developed the formula for drug dosage calculation, the alarming procedure, and the information of the high alert medication. In the satisfaction items, the mean score of 'This application is helpful to perform drug dosage calculation' was 3.14. However, 'I satisfy this application' was relatively low as 2.94. There were no differences in satisfaction according to the daily use and frequency of use. Based on the results of this study, more advanced smartphone application for medication reconciliation of high-alert medications will provide an important platform for patient safety.

• Journal of Veterinary Clinics
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• v.22 no.1
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• pp.1-5
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• 2005

Seroprevalence of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) infections were surveyed in 875 domestic cats derived from 4 major cities and 4 provinces in Korea. Of those tested, 715 were healthy and 160 were sick. FeLV and FIV were tested with AGEN/sup ⓡ/ FeLV-FIV, a commercial combo test kit. Ten out of 875 cats (1.1 %) were seropositive for FeLV and none out of 875 cats (0%) was positive for FIV, respectively. The positive rates for FeLV were 3.8% in sick cats and 0.6% in healthy cats. The cats at the age of more than 1 year showed higher incidence rates than the younger ones. There were no significant relationships either with the environment or with the sex. The prevalence of seropositive FeLV was 0.7% in mixed cats and 1.6% in pedigree cats. With respect to the regional prevalence of the FeLV, the highest seroprevalence (9.5%) was found in Gyeongsang province.

• Korean Journal of Ecology and Environment
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• v.38 no.2 s.112
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• pp.137-145
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• 2005

Traditional screening techniques have missed up to 99% of microbial resources existing in the nature. Strategies of direct cloning of environmental DNAs comprising tine genetic blueprints of entire microbial metagenomes provide vastly more genetic information than is contained in the culturable. Therefore, one way to screening the useful gene in a variety of environments is the construction of metagenomic DNA library. In this study, the water samples were collected from Daecheong Reservoir in the mid Korea, and analyzed by T-RFLP to examine the diversity of the microbial communities. The crude DNAs were extracted by SDS-based freezing-thawing method and then further purified using an $UltraClean^{TM}kit$ (MoBio, USA). The metagenomic libraries were constructed with the DNAs partially digested with EcoRI, BamHI, and SacII in Escherichia coli DH10B using the pBACe3.6 vector. About 14.0 Mb of metagenomic libraries were obtained with average inserts 13 ${\sim}$ 15 kb in size. The genes responsible for degradation of 1, 2-dichloroethane (1, 2-DCE) via hydrolytic dehalogenation were identified from the metagenomic libraries by colony hybridization. The 1, 2-dichloroethane dehalogenase gene (dhlA) was cloned and its nucleotide sequence was analyzed. The activity of the 1, 2-DCE dehalogenase was highly expressed to the substrate. These results indicated that the dhlA gene identified from the metagenomes derived from Deacheong Reservoir might be useful to develop a potent strain for degradation of 1, 2-DCE.

• Food Science of Animal Resources
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• v.25 no.3
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• pp.357-364
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• 2005

To search probiotic microorganisms, we isolated Lactobacillus sp. from kefir, The Lactobacillus sp. strain showed $99.5\%$ of identity to species Lactobacillus rhamnosus by API kit. Lactobacillus rhamnosus showed high resistances to acidic environment, which grew well even at pH 2.0 and $1.0\%$ bile salt Enzyme activity of Lactobacillus rhamnosus was higher in amylase ($0.673\;{\mu}mol/min/mg$) than that in xylanase ($0.288\;{\mu}mol/min/mg$), cellulase($0.117\;{\mu}mol/min/mg$) and phytase($0.269\;{\mu}mol/min/mg$). Especially, the Lactobacillus rhamnosus showed high heat stability which remained $1{\times}10^6\;CFU/ml$ at $60^{\circ}C$. The maximum numbers of Lactobacillus rhamnosus on growth owe was reached at 24 h fermentation and pH was decreased to 4.6. The resistances of Lactobacillus rhamnosus to acidic pH and bile salt were better than that of Lactobacillus acidophilus used as control. When Lactobacillus rhamnosus was cultured with E. coli in MRS broth, E. coli was disappeared after 18 h. These result suggest that the isolated Lactobacillus rhamnosus has a useful probiotics properties.

• Radiation Oncology Journal
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• v.22 no.3
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• pp.217-224
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• 2004

Purpose: It is well known that the radiosensitivity of tumor cells can be significantly reduced under hypoxic conditions. Hypoxia-inducible factor-1 $\alpha$ (HIF-1 $\alpha$) plays a pivotal role in the essential adaptive responses to hypoxia. Therefore this study investigated the relationship between HIF-1 $\alpha$ expression and radiosensitivity. M Mouse hepatoma cell line hepafcic7 and HIF-1 $\beta$-deficient mutant cell line hepa1C4 were used to analyze the role of HIF-1 a. on radiosensitivity. These cells were exposed for 6 h to desferrioxamine (DFX) before radiation. HIF-1$\alpha$. expression was examined by Western blot. Apoptosis was assessed by DNA fragmentation, propidium iodide staining, and apoptotic cell death detection ELISA kit. Radiation sensitivity was determined using MTT assay. The radiobioiogical parameters, surviving fractions at 2 Gy and 8 Gy, and mean inactivation dose (MID) from the linear-quadratic model were used to assess radiation sensitivity in the statistical analyses. Results: The expression of HIF-1 $\alpha$. was Increased, whereas apoptosis was decreased, by radiation In the presence of DFX In hepal cl c7, but not In hepal C4. The radlosensitivity of hepal C4 cells was not significantly affected by DFX treatment. The radiosensitivlty of hepal cl c7 cells was significantly decreased in the presence of DFX Conclusion: The expression of HIF-1 w by hypoxia-mimic agent DFX reduced apoptosls and radiosensitlvity in mouse hepatoma cell line hepafclc7. These results suggested that HIF-1 u could be Induced by irradiation in hypoxic ceils of tumor masses, and that this mlght Increase radioresistance in hypoxic cells.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.562-567
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• 2008

The primary objective of this study was to select a probiotic starter for cheonggukjang using 60 strains isolated from rice straw. Among isolated strains, only 8 strains including strain B-59 evidenced proteolytic, amylolytic and soybean activity. These 8 strains were all gram-positive, spore-forming rods. The B-59 strain evidenced antimicrobial activity against Staphylococcus aureus, Listeria monocytogenes, Pseudomonas fluorescens, and Vibrio parahaemolyticus. The antimicrobial activity of isolated B-59 was verified by its ability to inhibit the growth of S. aureus, L. monocytogenes, P. fluorescens, and V. parahaemolyticus. The selected B-59 strain was indentified as Bacillus licheniformis, as shown by a result of 99.0% homology upon API kit analysis. The selected B-59 strain also displayed viability in pH 2.5 artificial gastric juice, artificial bile acid, NaCl (2, 4, 8, 16, 32%), and ethanol (4, 8, 16, 32%). The antioxidative activity of the strain B-59 culture was assessed via a DPPH free radical scavenging activity assay. The activity increased with an increasing in the fermentation time of strain B-59 for 20 hours.

• Journal of Biosystems Engineering
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• v.37 no.6
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• pp.420-428
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• 2012

Purpose: Porcine proliferative enteropathy(PPE), caused by the obligate intracellular bacterium Lawsonia intracellularis, is a widely distributed disease throughout the world causing substantial economic loss. The bacterial pathogen invades the intestinal epithelial cells which causes hyperplasia of the infected cells and leads to the process of disease pathogenesis. For diagnosing PPE in a pig farm in earlier stage, a rapid diagnosing test equipment is needed for farmers. To test the equipment appropriately, we prepare the samples and antibodies for rapid detecting the Lawsonia intracellularis in pig feces. Methods : To prepare the PPE infected samples, we sampled PPE suspected pig feces in a pig farm. To manufacture a anti-Lawsonia intracellularis antibody for capturing the Lawsonia intracellularis, the rabbit-anti LsaA synthetic peptide polyclonal antibody was inoculated to rabbits. To select the couple of antibodies which is most well sandwiched with the bacteria, ELISA test was done with PPE infected ileum samples. Finally, to verify the PPE infected feces which would be used to test the rapid kit, PCR test was done on the sampled PPE suspected feces Results : The rabbit-anti LsaA synthetic peptide polyclonal antibody is developed, and is verified to capture the bacterial well through the fluorescence antibody test. Also, we found that the monoclonal antibody and the polyclonal antibody could be used as couples for sandwiching the bacteria. Finally, through the PCR test for samples of pig feces, we could prepare the 150 PPE positive samples and 50 PPE negative samples. Conclusions : The manufactured polyclonal antibody and the imported monoclonal antibody could be used to capture the bacteria using the sandwich techniques. Also, the prepared PPE infected negative and positive samples could be used to test the performance of the rapid kit to capture the bacterium Lawsonia intracellularis.