• Korean Journal of Microbiology
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• v.44 no.1
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• pp.80-84
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• 2008

We constructed the null mutants of fission yeast Schizosaccharomyces pombe spDbp5 gene that is homologous to DEAD-box RNA helicase DBP5 in budding yeast Saccharomyces cerevisiae, which plays important roles in mRNA export out of nucleus. A null mutant in an $h^+/h^+$ diploid strain was constructed by replacing the spDbp5-coding region with an $ura4^+$ gene using one-step gene disruption method. Tetrad analysis showed that the spDbp5 is essential for vegetative growth. The haploid spDbp5 null mutants harboring pREP81X-spDbp5 plasmid showed extensive $poly(A)^+$ RNA accumulation in the nucleus and decrease in the cytoplasm after repression of spDbp5 expression. These results suggest that spDbp5 is also involved in mRNA export from the nucleus.

• Polymer(Korea)
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• v.28 no.5
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• pp.382-390
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• 2004

One of the significant natural bioactive materials is demineralized bone particle (DBP) whose has a powerful induce. of new bone growth. In this study, we developed the DBP loaded poly-lactide (PLA) and poly(L-lactide-co-glycolide) (PLGA) scaffolds for the possibility of the application of the tissue engineered bone. PLA/DBP and PLGA/DBP scaffolds were prepared by solvent casting/salt leaching method and were characterized by porosimeter, scanning electron microscopy. BMSCs were stimulated by osteogenic medium and characterized by histological stained Wright-Giemsa, Alizarin red, von Kossa, and alkaline phosphate activity (ALP). DBP impregnated scaffolds with BMSCs were implanted into the back of athymic nude mouse to observe the effect of DBP on the osteoinduction compared with control scaffolds. It can be observed that the porosity was above $90.2\%$ and the pore size was above 69.1$\mu$m. BMSCs could be differentiated into osteoprogenitor cells as result of wright-giemsa, alizarin red, von Kossa and ALP staining. In in vivo study, we could observed calcification region in PLA/DBP and PLGA/DBP groups, but calcification did not occur almost in control scaffolds. From these results, it seems that DBP as well as BMSCs play an important role for bone induction in PLA/DBP and PLGA/DBP scaffolds.

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.209-212
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• 2007

To evaluate the estrogenic activities of di-ethyl hexyl phthalate (DEHP) and di-butyl phthalate (DBP), two phthalates known as endocrine disrupters, we used MCF-7 human breast cancer cell line. As results, DBP and DEHP had estrogenic effects. In brief, the concentration of maximal MCF-7 cell proliferation was $10^{-7}M\;and\;10^{-8}M$ for DEHP and DBP, respectively. The ratio of maximal cell yield of the test compounds to that of $17{\beta}-estradiol$ was 87.5% for DEHP and 73.4% for DBP. In summary, both DEHP and DBP had cell proliferation potencies in the MCF-7 cell. Potencies ranged from approximately 10 to 100 times less than 17beta-estradiol. DBP was stronger than DEHP in the concentration of maximal efficacy. However, DEHP was stronger than DBP in the MCF-7 cell proliferation. Results from this study suggested that DEHP and DBP may play an important role in the estrogenic activity. Therefore, it is suggested that DEHP and DBP are estrogenic.

• Macromolecular Research
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• v.9 no.5
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• pp.267-276
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• 2001

In order to endow with new bioactive functionality from demineralized bone particle (DBP) as natural source to poly(L-lactide) (PLA) synthetic biodegradable polymer, porous DBP/PLA as natural/synthetic composite scaffolds were prepared and compared by means of the emulsion freeze drying and solvent casting/salt leaching methods for the possibility of the application of tissue engineered bone and cartilage. For the emulsion freeze drying method, it was observed that the pore size decreased in the order of 79$\mu\textrm{m}$ (PLA control) > 47$\mu\textrm{m}$ (20% of DBP) > 23 $\mu\textrm{m}$ (40% of DBP) > 15$\mu\textrm{m}$ (80% of DBP). Porosities as well as specific pore areas decreased with increasing the amount of DBR. It can be explained that DBP acts like emulsifier resulting in stabilizing water droplet in emulsion. For the solvent casting/salt leaching method, a uniform distribution of well interconnected pores from the surface to core region were observed the pore size of 80 ∼70 $\mu\textrm{m}$ independent with DBP amount. Porosities as well as specific pore areas also were almost same. For pore size distribution by the mercury intrusion porosimeter analysis between the two methods, the pore size distribution of the emulsion freeze drying method was broader than that of the solvent casting/salt leaching method due to the mechanism of emulsion formation. Scaffolds of PLA alone, DBP/PLA of 40 and 80%, and DBP powder were implanted on the back of athymic nude mouse to observe the effect of DBP on the induction of cells proliferation by hematoxylin and eosin staining for 8 weeks. It was observed that the effect of DBP/PLA scaffolds on bone induction are stronger than PLA scaffolds, even though the bone induction effect of DBP/PLA scaffold might be lowered than only DBP powder, that is to say, in the order of DBP only > DBP/PLA scaffolds of 40 and 80% DBP > PLA scaffolds only for osteoinduction activity. In conclusion, it seems that DBP plays an important role for bone induction in DBP/PLA scaffolds for the application of tissue engineering area.

• Journal of environmental and Sanitary engineering
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• v.19 no.1
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• pp.50-56
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• 2004

Dibutyl phthalate (DBP) is used extensively in the plastic industry and has been known as an endocrine disruptor. Present study was undertaken to examine whether DBP can induce oxidative stress in mice. In this study, oxidative stress was measured in terms of the modification of lipid peroxidation and gamma-glutamyl transferase (GGT) activity. The serum toxicity index, level of lipid peroxidation and triglyceride (TG), and activity of GGT were measured in male ICR mice after a single administration of DBP (5 g/kg, po). DBP did not alter serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, glucose and cholesterol level. However, the treatment with DBP was found to significantly increase the level of lipid peroxidation in liver and lung. The TG content and activity of GGT in the liver of DBP-exposed animals was also increased. These results indicate that DBP can induce mild oxidative stress in mice. The GGT activity is considered to be increased as one of the adaptive defense mechanisms to oxidative stress induced by DBP.

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.218-222
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• 2007

Di(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) were screened for estrogenic activity using a recombinant yeast screening system consisted with estrogen receptors and ${\beta}-galactosidase$ as reporter gene. The chemicals showed estrogenic activity in ranges of $1{\times}10^{-10}\;to\;1{\times}10^{-7}M(DEHP)\;and\;of\;1{\times}10^{-9}M\;to\;1{\times}10^{-6}M(DBP)$ respectively. $17{\beta}-estradiol$, as a positive control of, showed maximal activity at $1{\times}10^{-9}M$. The concentration of half-maximal estrogenic activity was $1{\times}10^{-9}M$ for both chemicals. However, the concentration of maximal estrogenic activity was $1{\times}10^{-7}M$ for DEHP and $1{\times}10^{-8}M$ M for DBP. These results suggested that DBP was higher in relative potencies and more sensitive than DEHP. In conclusion, DEHP and DBP were both estrogenic, even though DBP was more reactive to estrogen receptor.

• Polymer(Korea)
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• v.34 no.5
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• pp.398-404
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• 2010

We fabricated sponge and poly(lactide-co-glycolide)(PLGA) scaffolds impregnated demineralized bone particle(DBP)(DBP/PLGA) and investigated proper condition to proliferation and phenotype maintenance of intervertebral disc(IVD) cells by comparison between DBP/PLGA scaffold and DBP sponge. DBP/PLGA scaffolds were prepared by solvent casting/salt leaching. Human IVD cells were seeded in scaffolds of two types. Cell viability and proliferation according to scaffolds were analyzed by WST assay and SEM. RT-PCR was assessed to measure mRNA expression of aggrecan and type II collagen of human IVD cells. In WST assay results, cell viability in scaffolds impregnated DBP/PLGA scaffold were higher than DBP sponge. We could observe that disc cell mRNA expressed better in DBP/PLGA scaffold than DBP sponge. We concluded that the using of DBP/PLGA in terms of scaffold fabrication for bio-disc with human IVD cells is helpful growth of disc cells maintenance of phenotypes.

• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.518-523
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• 2008

Experiments were conducted to assess the quality properties of steamed fish paste by addition level, along with a fish meat replacement(dried bovine plasma). The moisture, crude protein, crude fat and ash contents evidenced partially significant difference among the controls, DBP1, DBP2 and DBP3 groups(p<0.05). The pH values of the steamed samples were higher than those of the non-steamed samples, and when the content of the dried bovine plasma as meat replacement agent was increased, the pH was increased. The water holding capacity of the steamed fish past samples, along with the replacement levels were significantly higher than in the samples without the meat replacer(p<0.05). The range of cooking loss was $5.19{\sim}5.38%$. Structural weakening of the boiled samples was significantly higher than that observed in the fried sample. Hardness and chewiness were increased slightly by the addition of bovine plasma, but gel strength evidenced a pattern of decreased in DBP1, DBP2 and DBP3 groups. The result of our sensory evaluation on taste, texture, color and overall acceptance evidenced significant differences among the controls, DBP1, DBP2 and DBP3 groups, and the sensory score of color was the highest.

• Polymer(Korea)
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• v.32 no.2
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• pp.109-115
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• 2008

Because demineralized bone particle (DBP) contains various bioactive molecules such as cytokines, it is widely used biomaterials in the field of tissue engineering. In this study, we investigated the effect of 2-dimensional DBP/PLGA hybrid films on adhesion, proliferation and phenotype maintenance of intervertebral disc cells. PLGA films incorporated with different amount (0, 10, 20, 40 and 80 wt%) of DBP were prepared by the solvent evaporation method and characterized by scanning election microscopy (SEM). PLGA film has a flat and smooth surface. According to the increase of content of DBP, the surface of DBP/PLGA film exhibited few agglomerates and increased the roughness of the surface. Annulus fibrosus (AF) and nucleus pulposus (NP) cells were cultured on PLGA and DBP/PLGA film surface, and then examined the cell adhesion and proliferation by the cell count and SEM observation. The result of cell count and SEM observation revealed that 10 and 20% DBP in DBP/PLGA films were superior to adhesion and proliferation of both AF and NP cells. We confirmed that specific gene expression of disc cells on DBP/PLGA film based on the cell count result. Disc cells seeded on 20% DBP/PLGA film expressed the gene of type I and II collagen continuously. Therefore, pertinent content of biomaterials could provide more appropriate condition on adhesion and proliferation of cell. And this results may be used as a basic data for the intervertebral disc regeneration using tissue engineering.

• Korean Journal of Environmental Biology
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• v.22
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• pp.47-53
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• 2004

Among the phthalic esters, di-butyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP), which are categorized endocrine disrupting chemicals, account toy up to 80％ of the world production. Nine phthalic esters were quantitatively determined in water and in sediment samples from Gawngyang Bay and Seomjin River estuary. This might be the first report in contamination of phthalates in the marine environment of Korea. DBP and DEHP were detected with the high concentration and high frequency, while the other phthnlic compounds were below the detection limits. The aveyage concentyations of DBP and DEBP in sediment from Gawngyang Bay were 33.8 ng g$\^$-1/ and 67.4 ng g$\^$-1/ on a dry weight basis, respectively. The concentrations in surface watey from Seomjin River estuary were in the range of 62.7∼333.8 ng L$\^$-1/ for DBP and 25.6 ng L$\^$-/∼116.1 ng L$\^$-1/ for DBHP. In sediments from Seomjin River estuary, DBP ranged 9.1∼149.3 ng g$\^$-1/, and DEHP 46.3∼156.3 ng g$\^$-1/. Phthalic esters concentrations found in Seomjin River estuary were much less than those in other rivers in Korea. Distribution pattern of DBP and DEHP concentrations in Seonliin River estuary indicates that both compounds aye introduced to Gwangyang Bay through run-off.