• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.619-624
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• 2013

Background: Colorectal cancer (CRC) exists in a more common sporadic form and less common hereditary forms, associated with the Lynch syndrome, familial adenomatous polyposis (FAP) and other rare syndromes. Sporadic CRC is believed to arise as a result of close interaction between environmental factors, including dietary and lifestyle habits, and genetic predisposition factors. In contrast, hereditary forms such as those related to the Lynch syndrome result from inheritance of germline mutations of mismatch repair (MMR) genes. However, in certain cases, the influence of low penetrance alleles in familial colorectal cancer susceptibility is also undeniable. Aim: To investigate the genotype frequencies of MLH1 promoter polymorphism -93G>A and to determine whether it could play any role in modulating familial and sporadic CRC susceptibility risk. Methods: A case-control study comprising of 104 histopathologically confirmed CRC patients as cases (52 sporadic CRC and 52 Lynch syndrome patients) and 104 normal healthy individuals as controls was undertaken. DNA was extracted from peripheral blood and the polymorphism was genotyped employing PCR-RFLP methods. The genotypes were categorized into homozygous wild type, heterozygous and homozygous variants. The risk association between these polymorphisms and CRC susceptibility risk was calculated using binary logistic regression analysis and deriving odds ratios (ORs). Results: When risk association was investigated for all CRC patients as a single group, the heterozygous (G/A) genotype showed a significantly higher risk for CRC susceptibility with an OR of 2.273, (95%CI: 1.133-4.558 and p-value=0.021). When analyzed specifically for the 2 types of CRC, the heterozygous (G/A) genotype showed significantly higher risk for sporadic CRC susceptibility with and OR of 3.714, (95%CI: 1.416-9.740 and p-value=0.008). Despite high OR value was observed for Lynch syndrome (OR: 1.600, 95%CI: 0.715-3.581), the risk was not statistically significant (P=0.253). Conclusion: Our results suggest an influence of MLH1 promoter polymorphism -93G>A in modulating susceptibility risk in Malaysian CRC patients, especially those with sporadic disease.

• Journal of Nutrition and Health
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• v.48 no.6
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• pp.468-475
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• 2015

Purpose: Genetic polymorphisms in antioxidant defense and detoxification genes may modulate the levels of oxidative stress biomarkers. Methods: A total of 301 healthy preschool-aged children in the Seoul and Kyung-gi areas were recruited. DNA was extracted from blood for genotyping of manganese superoxide dismutase (Mn-SOD) Val16Ala, glutathione S-transferase (GST) P1 Ile105Val, GSTT1 present/null, and GSTM1 present/null polymorphisms by PCR-restriction fragment length polymorphism or multiplex PCR analyses. In addition to a questionnaire survey, the levels of urinary 8-hydroxyl-2-deoxiguanosine (8-OHdG) and plasma malondialdehyde (MDA) were measured by ELISA. Results: Significantly higher urinary 8-OHdG concentrations were observed in GSTP1 Ile/Val + Val/Val genotype (p = 0.030), and tended to be higher in Mn-SOD Val/Val genotype (p = 0.065). On the other hand, exposure to environmental tobacco smoking (ETS) and interaction between ETS and gene polymorphisms did not significantly influence either urinary 8-OHdG concentrations or serum MDA. Conclusion: Based on our findings, GSTP1 Ile/Val gene polymorphisms might modulate the levels of oxidative stress biomarkers in healthy preschool children.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1460-1468
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• 2007

In this study, an approx. 2.5-kb gene fragment including the catalase gene from Rhodospirillum rubrum S1 was cloned and characterized. The determination of the complete nucleotide sequence revealed that the cloned DNA fragment was organized into three open reading frames, designated as ORF1, catalase, and ORF3 in that order. The catalase gene consisted of 1,455 nucleotides and 484 amino acids, including the initiation and stop codons, and was located 326 bp upstream in the opposite direction of ORF1. The catalase was overproduced in Escherichia coli UM255, a catalase-deficient mutant, and then purified for the biochemical characterization of the enzyme. The purified catalase had an estimated molecular mass of 189 kDa, consisting of four identical subunits of 61 kDa. The enzyme exhibited activity over a broad pH range from pH 5.0 to pH 11.0 and temperature range from $20^{\circ}C$ to $60^{\circ}C$C. The catalase activity was inhibited by 3-amino-1,2,4-triazole, cyanide, azide, and hydroxylamine. The enzyme's $K_m$ value and $V_{max}$ of the catalase for $H_2O_2$ were 21.8 mM and 39,960 U/mg, respectively. Spectrophotometric analysis revealed that the ratio of $A_{406}$ to $A_{280}$ for the catalase was 0.97, indicating the presence of a ferric component. The absorption spectrum of catalase-4 exhibited a Soret band at 406 nm, which is typical of a heme-containing catalase. Treatment of the enzyme with dithionite did not alter the spectral shape and revealed no peroxidase activity. The combined results of the gene sequence and biochemical characterization proved that the catalase cloned from strain S1 in this study was a typical monofunctional catalase, which differed from the other types of catalases found in strain S1.

• Applied Microscopy
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• v.40 no.4
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• pp.229-235
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• 2010

Cervical cancer is associated with low antioxidant status. It has a high prevalence especially amongst woman in Asia and is a leading cause of cancer death. Cancer chemotherapy in vivo improved in cases with high p53 expression in the tumor tissue. The restoration of p53 levels could be a potential strategy to increase chemoresponsiveness. Under circumstances where damage is extensive, p53 plays a direct role in trigering apoptosis. To investigate the effect of curcumin (CMN) as an antioxidant agent on anticancer agent 5-fluorouracil (5FU) induced apoptosis and p53 expression, HPV-18 positive HeLa cells were treated with noncytotoxic amounts of antioxidant. Curcumin induced apoptosis in cervical cancer cells. Morphological hallmarks of apoptosis such as nuclear fragmentation and internucleosomal fragmentation of DNA were observed. CMN caused upregulation of p53 expression, evident from Western blotting data and also increased the susceptibility/apoptosis induced by 5FU. These results show that increasing drug sensitivity of cervical cancer cells by upregulation of p53 using CMN is novel approach and could have a possible therapeutic potential in cervical cancer.

• Toxicological Research
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• v.20 no.2
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• pp.101-108
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• 2004

The different social reflections about the benefits and the potential risks of genetically modified (GM) crops have evolved with .different reactions in different countries. Many countries including Korea are working toward setting down new guidelines. Korea requires companies to label all food that contains more than 3% GM ingredients. One of the rapid and convenient detection methods of GM ingredients is amplification of the introduced DNAs by polymerase chain reaction (PCR). Many PCR kits for this purpose are commercially available. The objective of this study was to evaluate performance of commercialized GM crop detection kits. The results showed that 6 out of 15 kits tested did not meet the requirements even purposed by the manufacturers themselves in terms of stability, reproducibility, and detection limits, suggesting a potential quality control problem in their design stage or production line. The evaluation also suggests that, although the duplex and triplex detection kits allowed unambiguous detection in a single PCR reaction, the monoplex detection kits were the most sensitive to the detection of GM ingredients. The detection limits also differ between soybean and corn. Results from this study will be useful in the development of sound qualitative tracking systems of GM ingredients for monitoring throughout the cultivation of GM crops, their trans-boundary movement, and food production using GM grains as well as for complying with government guidelines associated with GM crops.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.161-168
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• 2005

In this study, we did the molecular typing of 39 environmental Legionella pneumophila serogroup 1 isolates collected from 2001-2003 in Busan using the pulsed-filed gel electrophoresis (PFGE). PFGE of SfiI fragments were divided into 10 pulsotypes $(A\~J)$, corresponding to $<65\%$ similarity and a subtype within each pulsotype was characterized by $>84\%$ similarity. The major cluster was pulsotype E $(46.2\%)$, which included 18 isolates and was divided into 4 subtypes $(E1\~E4)$. PFGE of NotI fragments were divided into 8 pulsotypes $(a\~h)$, corresponding to $<60\%$ similarity and a subtype within each pulsotype was characterized by $100\%$ similarity. The major cluster was pulsotype f $(38.5\%)$, which included 15 isolates. The ATCC type strain L. pneumophila serogroup 1 was identified as a different molecular pulsotype compare to the Busan isolates. It is possible that L. pneumophila serogroup 1 isolated in Busan with specific DNA pattern is comparable with those isolation in other cities in Korea.

• Journal of Dairy Science and Biotechnology
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• v.34 no.1
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• pp.9-20
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• 2016

Various microflora, including lactic acid bacteria, are important and necessary components of various cheeses and have significant roles in cheese manufacturing and ripening. In general, the starter culture and secondary microflora could affect the physicochemical properties of various cheeses and could contribute to modifications during manufacturing and ripening. Therefore, during cheese manufacturing and ripening, microbial diversity may depend on continuous interactions among microflora and various environmental conditions. The microbial diversity of cheese is very complex and difficult to control using the classical microbiological techniques. However, recent culture-independent methods have been rapidly developed for microflora in cheese, which could be directly detected using DNA (and/or RNA) in combination with culture-dependent methods. Therefore, this review summarizes state-of-the-art molecular methods to analyze microbial communities in order to understand the properties that affect quality and ripening as well as the complex microbial diversity of various raw-milk, long-ripened cheeses.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.268-274
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• 2006

Bacillus sp. DYL130 producing biosurfactant was isolated from soil samples in the Duck-yu mountain and identified as Bacillus sp. by analysis of 16S rDNA sequence. Purification of the biosurfactant was performed by using affinity chromatography and TLC. The biosurfactant of culture medium from Bacillus sp. DYL130 was eluted with 100% methanol using affinity chromatography. To remove methanol, a rotary evaporator was used and enrichment sample was dissolved in alkaline water(pH 10). The purified biosurfactant was identified by TLC. It was confirmed that the Rf value of the biosurfactant was 0.78. Antifungal activity against Botrytis cineria was showed the strongly activity as active antagonist. Maximum emulsification activity and stability were obtained from soybean oil. The critical micelle concentration (CMC) of purified biosurfactant was 35mg/l and the purified biosurfactant inhibited biofilm forming by Bacillus sp..

• Journal of Life Science
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• v.21 no.7
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• pp.985-991
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• 2011

The purpose of this study was to investigate the biological effect of obesity-induced oxidative damage on neurogenesis and early protein expression. Obesity was induced I thirty 4-week old male Sprague-Dawley rats through a high fat diet for 15 weeks. After one week of environmental adaptation, the rats were divided into 2 groups: high fat diet sedentary group (HDS, n=15) and high fat diet training group (HDT, n=15). Exercise training was performed 5 times a week for 8 weeks, with mild-intensity treadmill running for weeks 1-4 and moderate-intensity treadmill running for weeks 5-8. After the 8 week training period, we analyzed lipid profiles, serum 8-hydroxyguanosine (8-OHdG), liver tissue malondialdehyde (MDA) related to oxidative damage factors, nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), c-fos, c-jun, and extracellular signal regulated kinase (Erk) in the hippocampus. The results of this study are as follows. There were differences between HDS and HDT in triglyceride (TG) and total cholesterol (TC) (p<0.05). In high density lipoprotein (HDL-c), the HDT was higher than HDS after treadmill training (p<0.05). In 8-OHdG, the HDT was lower than HDS after treadmill training (p<0.05). Genetic expressions of c-jun, BDNF and MDA in the HDT were higher than in the HDS after treadmill training in hippocampus (p<0.05). Therefore, we conclude that 8 weeks of treadmill training can improve imbalanced lipid profiles, reduce oxidative damage, and activate neurogenesis in obese rats.

• Journal of Life Science
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• v.25 no.2
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• pp.136-150
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• 2015

Pseudomonas syringae pathovar tabaci is a plant pathogenic bacterium that causes wildfire disease in tobacco plants. In P. syringae pv. tabaci, PsyI, a LuxI-type protein, acts as an AHL synthase, while primary and secondary sequence analysis of PsyR has revealed that it is a homolog of the LuxR-type transcriptional regulator that responds to AHL molecules. In this study, using phenotypic and genetic analyses in P. syringae pv. tabaci, we show the effect of PsyR protein as a quorum-sensing (QS) transcriptional regulator. Regulatory effects of PsyR on swarming motility and production of siderophores, tabtoxin, and N-acyl homoserine lactones were examined via phenotypic assays, and confirmed by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR). Further qRT-PCR showed that PsyR regulates expression of these virulence genes in response to environmental signals. However, an upstream region of the gene was not bound with purified MBP-PsyR protein; rather, PsyR was only able to shift the upstream region of psyI. These results suggested that PsyR may be indirectly controlled via intermediate-regulatory systems and that auto-regulation by PsyR does not occur.