• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.877-887
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• 1996

The ideal membranes for membrane-covered oxygen probes system should be selectively permeable for oxygen and chemically inert, and have good mechanical strength. Polysulfone(PSf) was selected to develop the membrane for membrane-covered oxygen electrodes system. PSf membranes have properties such as good reproducibility, good mechanical strength, chemical inertness, and high heat resistance. PSf membranes were cast from polymer solution on the glass plate at constant temperature, and casting solvents used were tetrahydrofuran(THF), methylene chloride, and N-methyl-2-pyrrolidone(NMP). Tricresyl phosphate(TCP) as plasicizer was added to PSf to increase the softness of membrane. The permeation characteristics were observed for pure oxygen and nitrogen through pure PSf membranes by variable volume method and membrane-covered electrode system. The permeability coefficients of oxygen and nitrogen measured by variable volume method were slightly decreased with increasing of upstream pressure. The permeation properties of PSf membrane using methylene choride as casting solvent were not affected by the PSf amount of polymer solution. The permeability coefficients of oxygen and nitrogen for PSf membrane containing TCP were very slightly lower than those for pure PSf membrane, but ideal separation factors were slightly higher. The flexibility of PSf membrane containing 2wt% TCP was better than that of pure PSf membrane. It was expected that this increase in flexibility would solve the difficulty of fixing the membrane to the cathode. The membrane-covered oxygen probes system was composed of anode, cathode and electrolyte. The type of the anode was Ag/AgCl half-cell, that of cathode was Ag, and the electrolyte was 4N KCl solution. The result of sampled current voltametry for PSf membrane showed the plateu region at -0.3V~-1.0V. The correlation coefficient of oxygen partial pressure versus current for PSf membrane was relatively high, 0.99949. It was concluded that PSf membrane was the good candidate for the membrane-covered oxygen probes system.

• Journal of the Korean Vacuum Society
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• v.15 no.1
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• pp.97-102
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• 2006

Anodic alumina with self-organized and ordered nano hole arrays can be a good candidate of an irradiation mask to modify the properties of nano-scale region. In order to try using porous anodic alumina as a mask for ion-beam patterning, ion beam transmittance of anodic alumina was tested. 4 Um thick self-standing AAO templates anodized from Al bulk foil with two different aspect ratio, 200:1 and 100:1, were aligned about incident ion beam with finely controllable goniometer. At the best alignment, the transmittance of the AAO with aspect ratio of 200:1 and 100:1 were $10^{-8}\;and\;10^{-4}$, respectively. However transmittance of the thin film AAO with low aspect ratio, 5:1, were remarkably improved to 0.67. The ion beam transmittance of self-standing porous alumina with a thickness larger than $4{\mu}m$ is extremely low owing to high aspect ratio of nano hole and charging effect, even at a precise beam alignment to the direction of nano hole. $SiO_2$ nano dot array was formed by ion irradiation into thin film AAO on $SiO_2$ film. This was confirmed by scanning electron microscopy that the $SiO_2$ nano dot array is similar to AAO hole array.

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.947-956
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• 2004

The primary role of lipoprotein lipase(LPL) is the hydrolysis of triglycerides(TG) from the core of triglyceride-rich lipoproteins such as chylomicrons and very low density lipoproteins in plasma. Fatty acids liberated by LPL on capillary endothelial surfaces are available for tissues as energy sources especially in muscles or for storage in the form of TG in adipose tissues. Therefore, as the candidate gene related to the carcass traits of the beef cattle, we have directly sequenced the exon 5${\sim}$exon 6 region in the bovine LPL gene for discovery of single nucleotide polymorphism(SNP) with 24 unrelated Hanwoo(Korean cattle). Novel eight sequence variants were detected: three loci on exon 5, three on intron 5 and two on exon 6. All SNPs identified were strongly linked each other, and one hundred twenty eight Hanwoo samples were genotyped one SNP on intron 5 using PCR-restriction fragment length polymorphism method by digestion with Hae III restriction enzyme. The allele frequency of the polymorphism was 0.76 and 0.24. The effects of this polymorphism on the breeding values of the carcass weight, loin muscle area, back fat thickness and marbling score were analyzed using least square methods of SAS GLM. The marbling score of BB genotype was significantly higher than those of AA and AB genotypes(P<0.05). This result indicates that this polymorphism may be associated with the variation of marbling score. Further study is warranted to investigate the phenotypic association in Hanwoo.

• Korean Journal of Plant Resources
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• v.26 no.5
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• pp.533-538
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• 2013

Potatoes were first introduced outside the Andes region four centuries ago, and have become an integral part of much of the world's food. Potatoes were first introduced into Europe in the 16th century and Korea in the early 19th century. In the nutritional aspects, potatoes contain abundant vitamins and minerals, as well as an assortment of phytochemicals such as carotenoids and natural phenols. Chlorogenic acid constitutes up to 90% of potato natural phenols. Due to the high content of potato functional compounds, it has known that potatoes are effective in the prevention of various human diseases. Recently, color-fleshed potatoes 'Hongyoung' and 'Jayoung' were developed by RDA, and it has reported that they have high content of anthocyanin. Additionally they show higher radical scavenging activity compared to white or yellow fleshed potatoes. So it will be expected that the consumption of color-fleshed potatoes grandually increase by pre-peeled potatoes and color potato chips. This study was conducted to enhance the peel of color-fleshed potatoes utilization and to determine the biological activity of peel of color-fleshed potatoes extract. The anti-inflammatory effects on ethanol extract and its solvent fraction were also evaluated. The anti-inflammatory activities of $CHCl_3$ fraction was evaluated for inhibitory activities against lipopolysacchride(LPS) induced nitric oxide(NO) and prostaglandin $E_2(PGE_2)$ production as well as inducible nitric oxide synthase(iNOS) and cyclo oxygenase-2(COX-2) protein expressions in RAW264.7 cell lines. The fraction inhibitory activity for both tests with $IC_{50}$ values showed in the ranges of $25{\sim}50{\mu}g/ml$. This result revealed that $CHCl_3$ fraction of Jayoung's peel is expected to be good candidate for development into source of anti-inflammatory agent.

• Genomics & Informatics
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• v.9 no.2
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• pp.52-58
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• 2011

Osteoporotic fracture (OF), along with bone mineral density (BMD), is an important diagnostic parameter and a clinical predictive risk factor in the assessment of osteoporosis in the elderly population. However, a genome-wide association study (GWAS) on OF has not yet been clarified sufficiently. To identify OF-associated genetic variants and candidate genes, we conducted a GWAS in a population-based cohort (Korean Association Resource [KARE], n=1,427 [case: 288 and control: 1139]) and performed a de novo replication study in hospital-based individuals (Asan and Catholic Medical Center [ACMC], n=1,082 [case: 272 and control: 810]). In a combined meta-analysis, a newly identified genetic locus in an intergenic region at 10p11.2 (near genes FZD8 and ANKRD30A ) showed the most significant association (odd ratio [OR] = 2.00, 95% confidence interval [CI] = 1.47~2.74, p=$1.27{\times}10^{-6}$) in the same direction. We provide the first evidence for a common genetic variant influencing OF and genetic information for further investigation in bone metabolism.

• Journal of Life Science
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• v.21 no.9
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• pp.1301-1309
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• 2011

The major function of adipocytes is to store fat in the form of triglycerides. One of the signaling pathways known to affect adipogenesis, i.e. fat formation, is the WNT/${\beta}$-catenin pathway which inhibits the expression and activity of key regulators of adipogenesis. The purpose of this research is to find genes among the WNT/${\beta}$-catenin pathway which regulate adipogenesis by using small interfering (si) RNA and to find the association of single nucleotide polymorphisms (SNPs) of the gene with serum triglyceride levels in the human population. To elucidate the effects of ${\beta}$-catenin siRNA on adipogenesis key factors, PPAR${\gamma}$ and C/EBP${\alpha}$, we performed real-time PCR and western blotting experiments for the analyses of mRNA and protein levels. It was found that the siRNA-mediated knockdown of ${\beta}$-catenin upregulates adipogenesis key factors. However, upstream regulators of the WNT/${\beta}$-catenin pathway, such as DVL2 and LRP6, had no significant effects compared to ${\beta}$-catenin. These results indicate that ${\beta}$-catenin is a candidate gene for human fat accumulation. In general, serum triglyceride level is a good indicator of fat accumulation in humans. According to statistical analyses of the association between serum triglyceride level and SNPs of ${\beta}$-catenin, -10,288 C>T SNP (rs7630377) in the promoter region was significantly associated with serum triglyceride levels (p<0.05) in 290 Korean subjects. On the other hand, serum cholesterol levels were not significantly associated with SNPs of the ${\beta}$-catenin gene. The results of this study showed that ${\beta}$-catenin is associated with fat accumulation both in vitro and in the human population.

• Tuberculosis and Respiratory Diseases
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• v.54 no.6
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• pp.610-620
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• 2003

Background : 3p deletion has been shown to be the most frequently occurring change in lung cancers, suggesting the presence of a tumor suppressor gene in this region. Recent attention has focused on a candidate 3p14.2 tumor suppressor gene, FHIT. Therefore, the association of the expression of FHIT, with apoptosis, cell proliferation cycle and the clinicopathological features, including survival, were investigated Materials and Methods : 83 patients with non-small cell lung cancer, who underwent curative operation, between Jan. 1996 and Aug. 2000, at the Wonkwang university hospital, were analyzed. The expression of the FHIT was identified by immunohistochemical staining, and rate of apoptosis and cell proliferation cycle by flow cytometry. Results : 43% (36/83) of patients exhibited no FHIT expression. The rates of FHIT loss were 52% (28/54), 22% (5/23), 50% (3/6); 30% (11/37), 48% (16/33), 69% (9/13); 54% (30/56) and 22% (6/27), in squamous cell cancers, adenocarcinomas, large cell cancers, TNM stages I, II and III, smokers and non-smokers, respectively. All the differences in FHIT loss rates, according to the histopathology, TNM stages and smoking habits, were statistically significant. The median survival time and 2-year survival rate of the FHIT(-) group were 24 months and 44%, and those of the FHIT(+) group were 25 months and 51% (p>0.05), respectively. The apoptotic rate of the FHIT(-) and FHIT(+) groups were 50.72 (${\pm}13.93$) and 59.38 (${\pm}14.33$)%, respectively (p=0.01). The S- and G1-phase fractions of the FHIT(-) and FHIT(+) groups were 13.93 (${\pm}7.35$) and $51.50({\pm}23.15$)% and 15.65(${\pm}6.59$) and 54.16 (${\pm}20.25$)%, respectively (p>0.05). Conclusion : The loss of FHIT expression was increased to a greater extent with advancing TNM stage, smoking habits and squamous cell cancer compared to the adenocarcinomas. However, no survival differences were found according to the expression of FHIT. The apoptotic rate of the FHIT(+) group was greater than in the FHIT(-) group, but differences in the S- and G1-phase fractions, according to the expression of the FHIT, were not found.

• Applied Biological Chemistry
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• v.49 no.3
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• pp.227-232
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• 2006

Styela clava (also called as rough sea squirt or leathery tunicate) is regarded as native to the northwest Pacific region including Korea and widely distributed in parts of northwestern Europe, North America and Australia. To evaluate Styela clava as a potential bioactive agent, the antioxidant activity of aceton extracts from Styela clava (whole, substance and tunic) was tested by measuring inhibitory effect of $H_2O_2$ induced DNA damage using comet assay. Also, anticancer activity on human colon cancer cell (HT-29) was investigated by MTT reduction assay. The $200\;{\mu}M$ $H_2O_2$ induced DNA damage was inhibited with Styela clava aceton extract in dose dependent manner in human leukocytes. The maximum inhibition was by 62.8, 62.1 and 78.3% at the concentration of $50\;{\mu}g/ml$ of whole, substance and tunic extracts, respectively. The aceton extracts from S. clava were also found to inhibit the growth of human colon cancer cell. The cell proliferation rates decreased to 26.9, 30.6 and 12.0% at the concentration of $500\;{\mu}g/ml$ of whole, substance and tunic extracts, respectively. These results support that aceton extracts from S. clava may be a potential candidate as a possible antimutagenic and chemotherapeutic agent.

• Microbiology and Biotechnology Letters
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• v.49 no.4
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• pp.552-558
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• 2021

Traditional foods are manufactured according to the characteristics of each region for the nations of the world. Korea has mainly farmed, and seasonings have developed around rice and vegetables. In fermented foods, lactic acid bacteria such as Lactobacillus sp. and Pediococcus sp. and Bacillus sp. were isolated and identified from fermented foods. In this study, lactic acid bacteria were isolated and identified from commercially available traditional Korean fermented foods, and candidate strains were selected through antibacterial activity tests on human and fish disease bacteria. Thereafter, the final strain was selected by examining the resistance to simulated gastric and intestinal fluids, and hemolysis. The three (M1, K1, C13) final selected latic acid bacteria were miced with prebiotics and the antibacterial activity of synbiotics was evaluated. As for the fist antibacterial activity result, C13 showed high antibacterial acitivity in human diseases and fish diseases. Then, M1, K1 and C13, which did not produce β-haemolysis and were resistant to simulated gastric and intestinal fluids, were subjected to the second antibacterial activity of synbiotics. When the three prebiotics (FOS, GOS, Inulin) and probiotics (M1, K1, C13) were mixed, the antibacterial activity was increased or inhibited. Based on the 16S rRNA gene sequencing results, K1 and M1 were analyzed as Bacillus tequiensis 99.72%, Bacillus subtilis 99.65%, Bacillus inaquosorum 99.72%, Bacillus cabrialesii 99.72%, Bacillus stercoris 99.58%, Bacillus spizizenii 99.58%, Bacillus halotolerans 99.58%, and Bacillus mojavensis 99.51%. And C13 was analyzed as Bacillus velezensis 99.71%, Bacillus nematocida 99.36%, Bacillus amyloliquefaciens 99.44%, Bacillus atrophaeus 99.22%, and Bacillus nakamurai 99.44%.

• Journal of Life Science
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• v.32 no.1
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• pp.29-35
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• 2022

This study was conducted to analyze the genetic polymorphisms of dopamine receptor D4 (DRD4) in horse breeds and its association with substrate characteristics in Jeju crossbreds (Jeju Horse × Thoroughbred). Polymorphisms in DRD4 are candidate genes associated with temperament in various mammals, including humans. Single nucleotide polymorphism (SNP) G292A in the exon 3 region of the horse DRD4 has a reported association with curiosity and vigilance in thoroughbreds. Sanger sequencing was used to identify polymorphisms of the mutations in DRD4 in three horse breeds. The SNP frequency in Jeju horses was significantly different from the frequency in other breeds. Character evaluation, conducted in the Jeju crossbreds and scored using a temperament test and contact test, revealed a high correlation between each test. Comparison of the polymorphism in the DRD4 of horses and the results of the character evaluation revealed lower scores for all temperaments in horses carrying allele A. Comparison of the SNP of G292A and blood dopamine levels in Jeju crossbreds showed 2.87 times higher levels for the GA type than for the GG type. This study identified an association between DRD4 polymorphism and various test methods for evaluating horse temperament and levels of neurotransmitters. Further research could validate the use of this gene as a genetic marker for character evaluation.