• Journal of Food Hygiene and Safety
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• v.25 no.2
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• pp.153-161
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• 2010

The purpose of this study was to examine the appearance of norovirus in the water for food in food service institutions and the influence of physicochemical and microbial factors of norovirus in order to work out basic data to predict the detection of norovirus. Among 82 samples of water for food in food service institutions, norovirus appeared in 7 samples and the rate of appearance was 8.5%. As for the type of norovirus, one samples contained GI type (genotype GI-6) and six samples contained GII type (genotype GII-2, GII-4, GII-12). In the regression model of prediction of norovirus, the rate of appearance was correlated with $NH_3$-N, total solids and the consumption of $KMnO_4$, out of such variables as $NH_3$-N, total solids, the consumption of $KMnO_4$, depth, chloride and total colony counts, and its contribution rate for effectiveness was 78.60%. In order to examine the influential factor of environment upon the detection of norovirus, Pearson's correlation analysis was carried out. The predictable regression formula for appearance rate of norovirus was expressed as -1.818 + 42.677 [$NH_3$-N] + 0.023 [total solids] + 0.762 [consumption of $KMnO_4$] -0.009 [depth] -0.146 [chloride] + 0.007 [total colony counts] (R = 0.904, $R^2$ = 0.818, adjusted $R^2$ = 0.786, p < 0.05). The most influential factors upon the detection of norovirus were $NH_3$-N, total solids and the consumption of $KMnO_4$. In other words, when the measured values of $NH_3$-N, total solids and the consumption of $KMnO_4$ were higher, the possibility of appearance of norovirus increased.

• Korean Journal of Poultry Science
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• v.40 no.4
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• pp.305-313
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• 2013

The objective of this study was to investigate occurrence patterns of Clostridium perfringens on different raising periods in broilers. In different raising periods, we investigated the change in the gross lesion and microscopic histological findings of the mucose of the small intestine, colony forming unit (CFU) and the types C. perfringens with PCR assay. According to the gross lesions on the mucose of small intestine with 10-days-old broilers, the non-antibiotic group showed a higher value (0.6) than the antibiotic group (0.0). Whereas 20-days-old broilers with, the antibiotic treatment had a slightly lower value (1.0) than the non-antibiotic group (1.3). In the histological examination on the villi of the small intestine, there was no damage of the villi of the small intestine with 1-day-old broilers in both groups; however, the non-antibiotic group showed a higher value (0.4) than the antibiotic group (0.0) with 10-days-old broilers. In the non-antibiotic group, the CFU of C. perfringens of the fecal samples from the small intestine increased from 10 days of raising broilers and rapidly increase after 20 and 30 days of raising broilers. There was no detection of C. perfringens types with PCR assy in 1-day-old broilers, but we found C. perfringens type A in 10-, 20- and 30-days-old broilers. Although it is possible to raise healthy broilers by using antibiotics, the addition of antibiotics to concentrate feed is prohibited for public health. The results of this study would contribute to proper feeding management through the careful use of antibiotics.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10407-10412
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• 2015

Background: ${\beta}$-elemene, extracted from herb medicine Curcuma wenyujin has potent anti-tumor effects in various cancer cell lines. However, the activity of ${\beta}$-elemene against glioma cells remains unclear. In the present study, we assessed effects of ${\beta}$-elemene on human glioma cells and explored the underlying mechanism. Materials and Methods: Human glioma U87 cells were used. Cell proliferation was determined with MTT assay and colony formation assay to detect the effect of ${\beta}$-elemene at different doses and times. Fluorescence microscopy was used to observe cell apoptosis with Hoechst 33258 staining and change of glioma apoptosis and cell cycling were analyzed by flow cytometry. Real-time quantitative PCR and Western-blotting assay were performed to investigated the influence of ${\beta}$-elemene on expression levels of Fas/FasL, caspase-3, Bcl-2 and Bax. The experiment was divided into two groups: the blank control group and ${\beta}$-elemne treatment group. Results: With increase in the concentration of ${\beta}$-elemene, cytotoxic effects were enhanced in the glioma cell line and the concentration of inhibited cell viability ($IC_{50}$) was $48.5{\mu}g/mL$ for 24h. ${\beta}$-elemene could induce cell cycle arrest in the G0/G1 phase. With Hoechst 33258 staining, apoptotic nuclear morphological changes were observed. Activation of caspase-3,-8 and -9 was increased and the pro-apoptotic factors Fas/FasL and Bax were upregulated, while the anti-apoptotic Bcl-2 was downregulated after treatment with ${\beta}$-elemene at both mRNA and protein levels. Furthermore, proliferation and colony formation by U87 cells were inhibited by ${\beta}$-elemene in a time and does-dependent manner. Conclusions: Our results indicate that ${\beta}$-elemene inhibits growth and induces apoptosis of human glioma cells in vitro. The induction of apoptosis appears to be related with the upregulation of Fas/FasL and Bax, activation of caspase-3,-8 and -9 and downregulation of Bcl-2, which then trigger major apoptotic cascades.

• Herbal Formula Science
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• v.26 no.3
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• pp.223-236
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• 2018

Objectives : We compared the inhibitory effects of herb-combined remedies, which were recorded on "Yooam" prescription of Dongeuibogam, on cell migration and invasion, two critical cellular processes that are often deregulated during metastasis, in B16F10 melanoma cells. For this purpose, water extracts of Sipyukmiryukieum (SYMRKU), Danjacheongpitang (DJCPT), Cheongganhaeultang (CGHUT) and Jipaesan (JPS) were used. Methods : Cytotoxicity was assessed by an MTT assay. Wound healing and matrigel transwell assays were used to examine on B16F10 cell migration and invasion. The levels of mRNA and protein expression of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) were analyzed by RT-PCR and Western blotting. Results : Our data showed that DJCPT showed the strongest inhibitory effect among the four prescriptions in inhibiting cell motility of B16F10 melanoma cells within the concentration range that was not cytotoxic. The inhibitory potential of colony formation was higher in DJCPT and SYMRKU compared to the other two types of prescriptions, and the inhibitory effect of invasiveness is shown in order of DJCPT, SYMRKU, CGHUT and JPS. DJCPT, and SYMRKU strongly inhibited the activity and expression of MMP-2 and MMP-9, which are important mediators in cancer invasion, compared to CGHUT and JPS, and the increased expression of TIMP-1 and TIMP-2 was also more effective in these two prescriptions. In conclusion, DJCPT is expected to exhibit the most potent blocking effect on migration and invasion among four herb-combined remedies compared in B16F10 melanoma cells. Conclusion : Overall, the results of this study will be used as an important source to validate these prescriptions in animal models and to understand the mechanism of action of herbal remedies recorded in Dongeuibogam.

• BMB Reports
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• v.37 no.3
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• pp.282-291
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• 2004

Phytases catalyze the release of phosphate from phytic acid. Phytase-producing microorganisms were selected by culturing the soil extracts on agar plates containing phytic acid. Two hundred colonies that exhibited potential phytase activity were selected for further study. The colony showing the highest phytase activity was identified as Aspergillus niger and designated strain 113. The phytase gene from A. niger 113 (phyI1) was isolated, cloned, and characterized. The nucleotide and deduced amino acid sequence identity between phyI1 and phyA from NRRL3135 were 90% and 98%, respectively. The identity between phyI1 and phyA from SK-57 was 89% and 96%. A synthetic phytase gene, phyI1s, was synthesized by successive PCR and transformed into the yeast expression vector carrying a signal peptide that was designed and synthesized using P. pastoris biased codon. For the phytase expression and secretion, the construct was integrated into the genome of P. pastoris by homologous recombination. Over-expressing strains were selected and fermented. It was discovered that ~4.2 g phytase could be purified from one liter of culture fluid. The activity of the resulting phytase was 9.5 U/mg. Due to the heavy glycosylation, the expressed phytase varied in size (120, 95, 85, and 64 kDa), but could be deglycosylated to a homogeneous 64 kDa species. An enzymatic kinetics analysis showed that the phytase had two pH optima (pH 2.0 and pH 5.0) and an optimum temperature of $60^{\circ}C$.

• The Korean Journal of Mycology
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• v.27 no.2 s.89
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• pp.132-137
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• 1999

This study was carried out to develop the molecular marker for the detection of Pseudomonas tolaasii, a causative agent of bacterial brown blotch disease of oyster mushroom (Pleurotus ostreatus). When several primers designed from repetitive sequences and pectin lyase genes of bacteria were used to produce DNA polymorphism from different Pseudomonas spp. isolated from edible mushrooms, PEU1 primer derived from pectin lyase gene produced polymorphic bands differentiating P. tolaasii strains from other Pseudomonas species. Two bands, 1.0kb and 0.4kb, found commonly in 6 isolates of P. tolaasii were cloned into pGEM-T vector which were designated as pPTOP1 and pPTOP2, respectively, to use as probe. The 0.4 kb insert of pPTOP2 hybridized to only 6 isolates of P. tolaasii, but did not to the other Pseudomonas species. As few as $1.5{\times}10^3$ colony forming unit (cfu) of P. tolaasii could be detected by dot blot hybridization with the cloned 0.4kb DNA in pPTOP2.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.133-139
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• 2011

In this study, we determined the changes in microbial numbers in solar salts according to the manufacturing process and storage duration. The salt samples were harvested from salt farms in Shinan (area 2) and Yeonggwang (area 1). They were serially diluted ten-fold and then placed on 4 kinds of cultivable media (mannitol salt agar, eosin methylene blue, plate count agar, and trypticase soy agar). After incubation, we obtained 62 halophilic isolates from the salt samples. Coliform and general bacteria were not detected in all salt samples. By 16S rRNA sequencing analysis, we found 12 kinds of halophilic bacteria belonging to the genera Halobacillus, Halomonas, Bacillus, Idiomarina, Marinobacter, Pseudoalteromonas, Vibrio, Salinivibrio, Virgibacillus, Alteromonas, Staphylococcus and some un-known stains. In our study, we discovered two novel species that have a 16S rDNA sequence similarity below 97%.

• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1529-1538
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• 2017

Klebsiella pneumoniae is an opportunistic and clinically significant emerging pathogen. We investigated the relative roles of Toll-like receptor (TLR) 2 and TLR4 in initiating host defenses against K. pneumoniae. TLR2 knockout (KO), TLR4 KO, TLR2/4 double KO (DKO), and wild-type (WT) mice were inoculated with K. pneumoniae. Mice in each group were sacrificed after either 12 or 24h, and the lungs, liver, and blood were harvested to enumerate bacterial colony-forming units (CFU). Cytokine and chemokine levels were analyzed using enzyme-linked immunosorbent assay and real-time PCR, and pneumonia severity was determined by histopathological analysis. Survival was significantly shortened in TLR4 KO and TLR2/4 DKO mice compared with that of WT mice after infection with $5{\times}10^3CFU$. TLR2 KO mice were more susceptible to infection than WT mice after exposure to a higher infectious dose. Bacterial burdens in the lungs and liver were significantly higher in TLR2/4 DKO mice than in WT mice. Serum $TNF-{\alpha}$, MCP-1, MIP-2, and nitric oxide levels were significantly decreased in TLR2/4 DKO mice relative to those in WT mice, and TLR2/4 DKO mice showed significantly decreased levels of $TNF-{\alpha}$, IL-6, MCP-1, and inducible nitric oxide synthase mRNA in the lung compared with those in WT mice. Collectively, these data indicate that TLR2/4 DKO mice were more susceptible to K. pneumoniae infection than single TLR2 KO and TLR4 KO mice. These results suggest that TLR2 and TLR4 play cooperative roles in lung innate immune responses and bacterial dissemination, resulting in systemic inflammation during K. pneumoniae infection.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2975-2979
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• 2015

Background: Telomere length is closely associated with cellular radiosensitivity and WRAP53 is required for telomere addition by telomerase. In this research we assessed radiosensitivity of laryngeal squamous cell carcinoma Hep-2 cell lines after WRAP53 inhibition, and analyzed the molecular mechanisms. Materials and Methods: phWRAP53-siRNA and pNeg-siRNA were constructed and transfected into Hep-2 cells with lipofectamine. Expression of WRAP53 was analyzed by RT-PCR and Western-blottin, radiosensitivity of Hep-2 cells was assessed colony formation assay, and the relative length of telomeres was measured by QPCR. Results: The data revealed that the plasmid of phWRAP53-siRNA was constructed successfully, and the mRNA and protein levels of WRAP53 were both obviously reduced in the Hep-2 cell line transfected with phWRAP53-siRNA. After Hep-2 cells were irradiated with X-rays, the $D_0$ and $SF_2$ were 2.481 and 0.472, respectively, in the phWRAP53-siRNA group, much lower than in the control group ($D_0$ and $SF_2$ of 3.213 and 0.592) (P<0.01). The relative telomere length in the phWRAP53-siRNA group was $0.185{\pm}0.01$, much lower than in the untreated group ($0.523{\pm}0.06$) and the control group ($0.435{\pm}0.01$). Conclusions: Decreasing the expression of WRAP53 using RNA interference technique can enhance the radiosensitivity of Hep-2 cell lines by influencing the telomere length. WRAP53 is expected to be a new target to regulate the radiosensitization of tumor cells.

• Journal of Environmental Health Sciences
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• v.40 no.2
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• pp.88-97
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• 2014

Objectives: The aim of this study was to evaluate the occurrence of microbiological contamination of kitchen utensils and environments of food service operations at university located in Seoul, Korea. Methods: We collected swab samples from the surfaces of knives, chopping boards, floors, and drains, as well as drinking water and airborne bacteria samples from 20 food service operations. Three bacterial indicators and five food poisoning bacteria were measured quantitatively and qualitatively, respectively. We used selective culture media and the PCR assay targeting 16S rRNA gene for the microbiological analysis. Results: We detected bacterial indicators on knives or chopping boards in eight different food service operations and, three food service operations (I, M, and O) showed more than 3 log colony forming units $(CFU)/100cm^2$ on their knives, significantly higher than the others. The levels of bacterial indicators on the floors and drains in the cooking areas were much higher than those on the cooking utensils. S. aureus was detected on 10 floors and 8 drains. Culturable bacteria were identified in 5 drinking water samples, and food service operation B ($431.1CFU/m^3$) and C ($551.2CFU/m^3$) showed more than $400CFU/m^3$ of total airborne bacteria. Conclusions: These results suggest that some of food service operations in this study may require additional investigation to secure the microbial safety of cooking environments. In addition, further actions including hygiene education for employees and proper guidelines to maintain clean cooking environments should be prepared.