• Korean Journal of Microbiology
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• v.41 no.1
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• pp.24-37
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• 2005

This study was conducted to analyze the molecular epidemiological properties and to select the most efficient and reliable PCR method on 116 of Staphylococcus aureus (S. aureus) isolates from Korean cattle, black goat, pig, dog, chicken, mouse and also human clinical cases from hospital. The distribution patterns of SSG [species specific genes; coagulase (coa), protein A (spa), nuclease (nuc) and aroA (RsaI) gene] were analyzed by PCR method. Among the SSGs, the nuc-gene was found in all strains $(100\%)$ tested and followed by coa-gene $(87.9\%)$, spa-gene $(91.4\%)$ and aroA-gene $(26.7\%)$, in order. The genetic subtyping by RFLP method was performed on the coa [AluI] and aroA-gene [RsaI] PCR products. The mecA-gene PCR and PCR-RFLP techniques were chosen to detect and verify of MRSA strains. Only the human strains $(12.1\%)$ were detected the positive mecA-gene products (533 bp), which were divided into two specific bands [201 & 332 bp] by HhaI enzyme digestion. On coa-gene and spa-gene typing, coa-gene was typed with ten kinds of genotype and coa-3 type were determined as the most predominant genotype, while spa-gene was divided into eleven kinds of genotype and also spa-7 type were selected the most prevalent genotype based on their genetic variations. On the aroA and coa-gene subtyping by PCR-RFLP, aroA-gene products were discriminated with only seven types of genotype, while coa-gene products were further divided into an eleven genotype, respectively. In comparison of SID values of five PCR based typing methods, the coa-PCR-RFLP (SID0.894) was evaluated the most efficient and reliable tools and followed by coa-PCR (SID0.883) and aroA-PCR-RFLP (SID0.462), in order. In conclusion, we could determined that the coa-PCR-RFLP method was the most suitable genetic analysis tool for S. aureus and MRSA strains from domestic animals and humans.

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.386-395
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• 2007

A total of 27 strains of Vibrio parahaemolyticus (18 strains isolated from Korea and 9 strains from Japan) were serotyped and examined for biochemical characteristics, antimicrobial susceptibility patterns, cytotoxicity assay, thermostable direct hemolysin (TDH) production and molecular epidemiology. Using polymerase chain reaction (PCR) method and DNA probe hybridization method, the strains were tested for toxR, tdh, trh and ORF 8 genes. The V. parahaemolyticus isolated from patients were belonged to 8 different serotypes : O3:K6, O1:K38, O3:K57, O4:K9, O4:Kl2, O4:K68, O5:Kl5 and O6:K46. Urease-positive strain possessed the trh gene, and conversely, urease-negative strains lacked the gene, indicating that urease production by V. parahemolyticus strains strongly correlates with the possession of the trh gene. Most strains showed multiple resistant to more than three antibiotics and the antibiogram could be classified into 6 group (I to VI). All of the O3:K6 strains isolated in South Korea and Japan producted TDH at high levels. The TDH titers ranged between 256 and 2.048, and the average titer was 1009. To distinguish the new and increasingly common V. parahaemolyticus strains from clinical isolates, ORF 8 is a useful genetic marker. After Southern hybridization, the HindIII restriction fragment patterns of the tdh gene were grouped one type, respectively. One type showed two bands one of which was 4.3kb and the other was 11.5kb in size. Variation between the O3:K6 serotype are minor when compared to the differences seen with the non O3:K6 strains. The migration patterns of Not I -digested of the total DNA of the O3:K6 strains were similar, and only slight variations were observed between the serotypes. By contrast, the O3:K6 strains and non O3:K6 had markedly different profiles. In conclusion, Random amplified polymorphic DNA (RAPD) profile using appropriate primers was an effective epidemiological marker.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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• pp.6619-6625
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• 2014

Background: Numerous studies have explored the influence of XPD Lys751Gln and/or Asp312Asn polymorphisms on skin cancer susceptibility. However, the results remain inconclusive. To derive a more precise estimation, we conducted a comprehensive search to identify all available published studies and performed a meta-analysis. Materials and Methods: Electronic literature searches of the PubMed, CBM and CNKI databases were performed up to March 2014. Odds ratios (ORs) with 95% confidence intervals (CIs) were applied to assess the strength of associations. Results: Seventeen case-control studies were included with a total sample size of 6, 113 cases and 11, 074 controls for the XPD Lys751Gln polymorphism, and 10 studies (3, 840cases and 7, 637 controls) for the XPD Asp312Asn polymorphism were pooled for analysis. Overall, no significant associations were found between the XPD Lys751Gln polymorphism and skin cancer risk in any genetic model. On stratified analysis by tumor type, XPD Lys751Gln polymorphism was not associated with increased risk of non-melanoma skin cancer, but was significantly related with increased risk of cutaneous melanoma (Gln/Gln vs Lys/Lys: OR=1.15, 95%CI=1.02-1.29, p=0.023; dominant model: OR=1.09, 95%CI=1.01-1.18, p=0.036). For the XPD Asp312Asn polymorphism, no significant association with skin cancer risk was observed in overall or subgroup analyses. Conclusions: The present meta-analysis suggests that the XPD Lys751Gln polymorphism may contribute to the risk of cutaneous melanoma from currently available evidence. Further investigations are needed to obtain more insight into possible roles of these two polymorphisms in skin carcinogenesis.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.522-526
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• 2007

Since newly emerged disease, the Severe Acute Respiratory Syndrome (SARS), spread from Asia to North America and Europe rapidly in 2003, many researchers have tried to determine where the virus came from. In the phylogenetic point of view, SARS virus has been known to be one of the genus Coronavirus, but, the overall conservation of SARS virus sequence was not highly similar to that of known coronaviruses. The natural reservoirs of SARS-CoV are not clearly determined, yet. In the present study, the genomic sequences of SARS-CoV were analyzed by bioinformatics techniques such as multiple sequence alignment and phylogenetic analysis methods as well multivariate statistical analysis. All the calculating processes, including calculations of the relative synonymous codon usage (RSCU) and other genomic parameters using 30,305 coding sequences from the two genera, Coronavirus, and Lentivirus, and one family, Orthomyxoviridae, were performed on SMP cluster in KISTI, Supercomputing Center. As a result, SARS_CoV showed very similar RSCU patterns with feline coronavirus on the both axes of the correspondence analysis, and this result showed more agreeable results with serological results for SARS_CoV than that of phylogenetic result itself. In addition, SARS_CoV, human immunodeficiency virus, and influenza A virus commonly showed the very low RSCU differences among each synonymous codon group, and this low RSCU bias might provide some advantages for them to be transmitted from other species into human beings more successfully. Large-scale genomic analysis using bioinformatics techniques may be useful in genetic epidemiology field effectively.

• Korean Journal of Microbiology
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• v.53 no.3
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• pp.156-162
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• 2017

Legionnaires' disease (LD) is a severe and potentially fatal pneumonia caused by colonization of human-made water system and subsequent aerosolization and inhalation of Legionella bacteria. A total of 147 Legionella strains was isolated from environmental water sources from public facilities in Gyeonggi-do, South Korea. The distribution of Legionella isolates was investigated according to facility type, and sample type. L. pneumophila was distributed broadly throughout Gyeonggi-do, accounting for 85.7% of the isolates, and L. pneumophila serogroup (sg) 1 predominated in all of the public facilities. L. wadsworthii predominated among non-L. pneumophila species. We performed comparative analyses of L. pneumophila sg 1 isolated from environment water of public facilities in Gyeonggi-do by pulsed field gel electrophoresis (PFGE) and sequence-based typing (SBT). Thirty-two isolates were classified into 22 types by PFGE and 9 sequence types (STs) by SBT and categorized into 3 groups. ST1 was the most prevalent sequence type and two STs obtained in this study had unique allelic profiles. The use of SBT data from different countries for epidemiology study of LD constitutes a technically uncomplicated and relatively easy method for strain subtyping, especially compared to other contemporary techniques.

• Korean Journal of Health Education and Promotion
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• v.28 no.1
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• pp.103-113
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• 2011

Objective: This study was conducted to investigate the relationship between the degree of stress and social support among residents in a rural area. Methods: We used the baseline data of the Korean Genomic Rural Cohort (KGRC), a sub-cohort of the Korean Genome Epidemiology Study (KOGES) that collected data about relationships among environmental, genetic risk factors, and chronic illness in Korean adults since November 2005. The cases chosen for the study included 1737 men and women, aged 40 to 70, living in a rural area of Wonju-city, South Korea. A questionnaire interviewing method was addressed in 2006. The final participants consisted of 1349 participants, of which 589 were male (43.7%) and 760 were female (56.3%). We applied the hierarchical multiple regression analysis with three stages. The first and second stages include socio-demographic and health-related behaviour factors and the third stage includes more social support factors. Results: The main findings revealed that the amount of social support and health-related behaviour significantly influenced the level of stress the subjects reported. The degree of stress was shown to be significantly higher for the following individuals: females, those who were divorced, the bereaved, participants who suffer from chronic disease, and non-exercisers. Low social support was shown to be negatively associated with stress. Conclusion: Social support factors along with socio-demographic and health-related behavior had an influence on stress levels in Korean rural adults. It is necessary to relieve residents from stress through diverse social support programs and healthy living initiatives.

• Journal of Genetic Medicine
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• v.12 no.2
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• pp.92-95
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• 2015

Purpose: Increased maternal age is a major risk factor for chromosomal abnormalities. The maternal age-specific risk of fetal trisomy was theoretically calculated. We investigated the actual frequency of fetal trisomy between 16 and 24 gestational weeks in pregnant women over the age of 34 at delivery. Materials and Methods: We retrospectively, over a four-year period, reviewed the medical records of women with singleton pregnancies that started their antenatal care before the 10th week of pregnancy. Pregnant women aged 34 to 45 years at the time of delivery were enrolled and divided into groups of one-year intervals. We investigated the frequency of Down syndrome and all trisomies as a function of the maternal age and compared with the theoretical maternal-age-specific risk. Results: Of the 5,858 pregnant women enrolled in the study, the rate of trisomy 21 was 0.29% (17 cases). The observed frequencies of trisomy 21 in women with maternal ages of 35 years and 40 years were 1:1,116 and 1:141, respectively. The rate of all trisomies was 0.39% (23 cases). The observed frequencies of all trisomies in women with maternal ages of 35 years and 40 years were 1:372 and 1:56, respectively. Conclusion: The frequencies of Down syndrome and all trisomies were proportional to the maternal age. However, the observed frequencies of Down syndrome and all trisomies between the 16 and 24 gestational weeks were lower than the theoretical rates.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1317-1320
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• 2012

Biliary tract cancers, broadly described as malignancies that arise from the biliary tract epithelia, are usually divided into two major clinical phenotypes: cholangiocarcinoma and gallbladder cancer, differing in etiopathogenesis, risk factors, and perhaps molecular and genetic signatures. Atypical symptoms and lack of tumor biomarkers make it difficult to diagnose in early stages. At the time of presentation, few patients are candidates for potentially curative surgical resection. We here assessed and compared features of a total of 150 cases divided into extra- and intrahepatic cholangiocarcinomas and gallbladder cancers (GBC). Althought there were no significant differences in serum tumour marker levels, GBC patients had the poorest prognosis. Furthermore, gallbladder cancer respond poorly to chemotherapy or radiation therapy and approximately half of untreated patients died within 10 months. Therefore, treatment for patients with gallbladder cancer is still in challenge. Outcomes and survival of these patients had improved little over the past three decades - a period in which new successful treatments have greatly contributed to the prolonged patient survival for many other cancers.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.275-278
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• 2016

The membrane epithelial mucin MUC1 is expressed at the luminal surface of most simple epithelial cells, but expression is greatly increased in most breast cancers. The aims of present study were to investigate expression of the MUC1 gene and interactive affects in metastases. Whole cell RNA isolation from 50 sentinel lymph nodes (SNLs) of breast cancer patients was performed using reverse transcription and real-time PCR. All patients were diagnosed with breast cancer and without metastasis, confirmed by IHC staining. The evaluation of tumor and normal samples for expression of MUC1 gene, the results were 49.1% non-expressive and 45.3% expression (Student t, p = 0.03). Also in comparison of normal breast tissue and breast cancer SLN for MUC1 gene, MUC1 negative SLNs were 75.0% (18 samples) and MUC1 positive samples were 25.0% (6 samples). Over-expression of MUC1 gene may offer a target for therapy related to progression and metastasis in women with breast cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2093-2097
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• 2016

Background: HCV is a major global health problem. IL-27 is a member of the IL-6/IL-12 cytokine family with a broad range of anti-inflammatory properties. Recent studies highlighted the effect of a SNP in the IL-27 promoter region on modulating the progression of infectious diseases and individual responses to therapy. Aim of the work: The present study investigated the potential role of (-964 A/G) SNP in the promoter region of IL-27p28 gene (alleles rs153109) on the outcome of HCV infection among genotype 4a infected patients. Materials and Methods: HCV genotyping confirmed that all of the HCV-infected patients had genotype 4a infection. Genomic DNA was extracted from 111 patients with chronic HCV infection, 42 spontaneous resolvers (SR) and 16 healthy controls. IL- 27p28.rs153109 genotyping was assessed using PCR-RFLP then confirmed by DNA sequencing. Results: The frequency of IL-27-p28.rs153109AA, AG, and GG genotypes among chronically infected subjects were 74.8 %, 25.2%, and 0% while among the SR, they were 57.1%, 35.7%, and 7.14%, respectively. Our data show the unique presence of G/G genotype in the SR group (3 patients; 7.14%). Moreover, the "G" allele frequencies among chronic and resolved subjects were 12.6% and 25.0%, respectively (p=0.0136). Importantly, subjects with the GG genotype were more likely to clear their HCV infection than those with the AA genotype (p=0.0118). Conclusions: HCV genotype 4a subjects with the IL-27-p28.rs153109 A/G and G/G genotype were more likely to clear their HCV infection. Therefore, we propose IL- 27p28.rs153109SNPas a genetic biomarker for predicting HCV infection outcome.