• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.2
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• pp.151-157
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• 2003

Obtaining a sufficient amount of healthy keratinocytes from a small tissue is difficult. However, ORS cells can be a good source of epithelium since they are easily obtainable and patients do not have to suffer from scar formation at donor sites. Accordingly, the current study modified the conventional primary culture technique to overcome the low propagation and easy aging of epithelial cells during culturing. In a conventional primary culture, the average yield of human ORS tells is 2.↑ $\times$ 10$^3$cells/follicle based on direct incubation in a trypsin (0.1%)/EDTA(0.02%) solution for 15 min at 37$^{\circ}C$, however, our modified method was able to obtain about 6.9 $\times$ 10$^3$cel1s/follicle using a two-step enzyme digestion method involving dispase (1.2 U/mL) and a trypsin (0.1%)/EDTA (0.02%) solution. Thus, the yield of primary cultured ORS cells could be increasd three times higher. Furthermore, a total of 2.0 $\times$ 10$^{7}$ cells was obtained in a serum-free medium. while a modified E-medium with mitomycin C-treated feeder tells produced a total of 6.3 $\times$ 10$^{7}$ Cel1s over 17 days When Starting With 7.5 $\times$ 10$^4$cells. Finally, We Confirmed the effectiveness of our ORS tell isolation method by presenting their ability for reconstructing the bioartificial skin epithelium in vitro

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.6
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• pp.2677-2684
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• 2011

This study was conducted to clarify relationships between BMI and the incidence of hypertension, hyperglycemia and hypercholesterolemia among health checkup examinees. The study sample consists of 3,402 adults aged 30s - 60s years, who underwent health check-up at a university hospital. during the Jan. 2007 to Dec. 2008.As a results, blood pressure level at the base line, ORs(95% CI) of hypertension compared with BMI category of 18.5-22.9(normal group) were 1.7(1.2-3.8) for obesity group I, and 2.9(1.7-6.2) for obesity group II. After adjusting for age and sex, ORs(95% CI) of hypertension compared with BMI category of normal group were 1.3(1.0-1.7) for obesity group I, 1.8(1.3-2.4) for obesity group II. Serum total cholesterol level at the base line, ORs(95% CI) of hypercholesterolemia compared with BMI category of normal group were 1.7(1.5-4.9) for obesity group I, and 2.8(1.8-5.3) for obesity group II. After adjusting for age and sex, ORs(95% CI) of hypercholesterolemia compared with BMI category of normal group were 1.5(1.1-1.9) for obesity group I, and 2.3(1.7-3.1) for obesity group II.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.6.1-6.15
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• 2023

Background: Polycyclic aromatic hydrocarbons (PAHs) are occupational and environmental pollutants generated by the incomplete combustion of organic matter. Exposure to PAHs can occur in various occupations. In this study, we compared PAH exposure levels among occupations based on 4 urinary PAH metabolites in a Korean adult population. Methods: The evaluation of occupational exposure to PAHs was conducted using Second Korean National Environmental Health Survey data. The occupational groups were classified based on skill types. Four urinary PAH metabolites were used to evaluate PAH exposure: 1-hydroxypyrene (1-OHP), 2-naphthol (2-NAP), 1-hydroxyphenanthrene (1-OHPHE), and 2-hydroxyfluorene (2-OHFLU). The fraction exceeding the third quartile of urinary concentration for each PAH metabolite was assessed for each occupational group. Adjusted odds ratios (ORs) for exceeding the third quartile of urinary PAH metabolite concentration were calculated for each occupational group compared to the "business, administrative, clerical, financial, and insurance" group using multiple logistic regression analyses. Results: The "guard and security" (OR: 2.949; 95% confidence interval [CI]: 1.300-6.691), "driving and transportation" (OR: 2.487; 95% CI: 1.418-4.364), "construction and mining" (OR: 2.683; 95% CI: 1.547-4.655), and "agriculture, forestry, and fisheries" (OR: 1.973; 95% CI: 1.220-3.191) groups had significantly higher ORs for 1-OHP compared to the reference group. No group showed significantly higher ORs than the reference group for 2-NAP. The groups with significantly higher ORs for 1-OHPHE than the reference group were "cooking and food service" (OR: 2.073; 95% CI: 1.208-3.556), "driving and transportation" (OR: 1.724; 95% CI: 1.059-2.808), and "printing, wood, and craft manufacturing" (OR: 2.255; 95% CI: 1.022-4.974). The OR for 2-OHFLU was significantly higher in the "printing, wood, and craft manufacturing" group (OR: 3.109; 95% CI: 1.335-7.241) than in the reference group. Conclusions: The types and levels of PAH exposure differed among occupational groups in a Korean adult population.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.2
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• pp.389-405
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• 2014

Outdated Channel State Information (CSI) was proved to have negative effect on performance in two-way relay networks. The diversity order of widely used opportunistic relay selection (ORS) was degraded to unity in networks with outdated CSI. This paper proposed a multiple relay selection scheme for amplify-and-forward (AF) based two-way relay networks (TWRN) with outdated CSI. In this scheme, two sources exchange information through more than one relays. We firstly select N best relays out of all candidate relays with respect to signal-noise ratio (SNR). Then, the ratios of the SNRs on the rest of the candidate relays to that of the Nth highest SNR are tested against a normalized threshold ${\mu}{\in}[0,1]$, and only those relays passing this test are selected in addition to the N best relays. Expressions of outage probability, average bit error rate (BER) and ergodic channel capacity were obtained in closed-form for the proposed scheme. Numerical results and Simulations verified our theoretical analyses, and showed that the proposed scheme had significant gains comparing with conventional ORS.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4441-4444
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• 2012

Background: Polymorphisms of the Taq I gene have been associated with prostate cancer risk. Methods:We applied a fixed-effects model to combine odds ratios (ORs) and 95% confidence intervals (95% CI). The Egger's test was carried out to evaluate potential publication bias. Results: A total of 10 case-control studies enrolling 1,141 prostate cancer patients and 1,685 controls were included in this meta-analysis. Compared with the T allele, the OR for the C allele was 0.81 (0.70-0.94). The ORs for CT and CC+CT genotypes were 0.86 (0.74-1.01) and 0.84 (0.73-0.97) compared to wide type genotype (homozygote TT). Conclusions: The present meta-analysis suggests that the TF gene Taq I polymorphism may reduce the prostate cancer risk in Asian populations.

• BMB Reports
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• v.43 no.10
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• pp.688-692
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• 2010

In a previous study, we recently claimed that dihydrotestosterone (DHT)-inducible dickkopf-1 (DKK-1) expression is one of the key factors involved in androgen-potentiated balding. We also demonstrated that L-ascorbic acid 2-phosphate (Asc 2-P) represses DHT-induced DKK-1 expression in cultured dermal papilla cells (DPCs). Here, we investigated whether or not L-threonate could attenuate DHT-induced DKK-1 expression. We observed via RT-PCR analysis and enzyme-linked immunosorbent assay that DHT-induced DKK-1 expression was attenuated in the presence of L-threonate. We also found that DHT-induced activation of DKK-1 promoter activity was significantly repressed by L-threonate. Moreover, a co-culture system featuring outer root sheath (ORS) keratinocytes and DPCs showed that DHT inhibited the growth of ORS cells, which was then significantly reversed by L-threonate. Collectively, these results indicate that L-threonate inhibited DKK-1 expression in DPCs and therefore is a good treatment for the prevention of androgen-driven balding.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.2033-2036
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• 2013

Many studies have suggested that the XRCC1 Arg280His gene polymorphism might be involved in the development of hepatocellular carcinoma (HCC). However, the results have been inconsistent. In this study, the authors performed a meta-analysis to assess the association between XRCC1 Arg280His and HCC susceptibility. Published literature from PubMed, EMBASE and CNKI Data was searched. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using fixed- or random-effects models when appropriate. Begg's test was used to measure publication bias. A total of 7 case-control studies covering 1,448 HCC cases and 1,544 controls were included. No significant variation in HCC risk was detected in any of the genetic models overall. In the stratified analysis, four studies with sample sizes over 300 produced similar results. The corresponding pooled ORs were not substantially altered after the exclusion of three studies deviating from Hardy-Weinberg equilibrium in the control group, which indicated reliability for our meta-analysis results.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.2
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• pp.83-89
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• 2005

This study aims to compare a self-reported and expert-observed method on ergonomic risk factors of Work-related Musculoskeletal Disorders (WMSDs). The checklist was developed based on the results of previous studies, and the symptoms of WMSDs were obtained using a self-reported questionnaire from 1,029 shipyard workers. The risk factors were assessed through the self-report by workers and video analysis by ergonomists. The symptom prevalence at the low back (59.2%), shoulders (50.8 %), and knees (49.7%) were relatively higher than those at other body parts. Odds ratios (ORs) by body parts were 2.48 to 2.90 for the risk job, and the ORs were significantly different from those of the low risk job. The risk factor scores by body parts between workers and ergonomist were very high correlation(r=0.82 to 0.92). The rates of self-report from risk job were 54.0% (elbow and arm) to 72.1 % (low back), but sometimes overestimated(105.7 to 122.6%) than those by ergonomists. The checklist, developed in this study, will be an efficient tool for the evaluation of risk jobs using self-report by workers.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3163-3168
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• 2013

Methylenetetrahydrofolate reductase (MTHFR) plays a central role in folate metabolism. This study with 381 esophageal cancer patients and 432 healthy controls was conducted to examine the association of MTHFR C677T and A1298C polymorphisms with susceptibility to esophageal cancer (EC) in a Chinese population. Compared with the CC genotype of MTHFR C677T, subjects carrying homozygote TT and variant genotypes (CT+TT) demonstrated reduced risk of EC with adjusted ORs (95% CI) of 0.44 (0.28-0.71) and 0.57 (0.37-0.88), respectively. However, no association was found between the MTHFR A1298C polymorphism and the risk of EC. Comparing to haplotype CA, haplotypes TA and TC could reduce the susceptibility to EC with adjusted ORs (95% CI) of 0.61(0.47-0.79) and 0.06 (0.01-0.43), respectively. In conclusion, the present study suggested that the MTHFR C677T polymorphism can markedly influence the risk of EC in Chinese.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.5
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• pp.2416-2432
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• 2017

In this paper, we investigate the security performance for cooperative networks over Nakagami-m fading channels. Based on whether the channel state information (CSI) of wiretap link is available or not, optimal relay selection (ORS) and suboptimal relay selection (SRS) schemes are considered. Also, multiple relays combining (MRC) scheme is considered for comparison purpose. The exact and asymptotic closed-form expressions for secrecy outage probability (SOP) are derived and simulations are presented to validate the accuracy of our proposed analytical results. The numerical results illustrate that the ORS is the best scheme and SRS scheme is better than MRC scheme in some special scenarios such as when the destination is far away from the relays. Furthermore, through asymptotic analysis, we obtain the closed-form expressions for the secrecy diversity order and secrecy array gain for the three different selection schemes. The secrecy diversity order is closely related to the number of relays and fading parameter between relay and destination.