• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.285-291
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• 2011

NCO terminated polyurethane prepolymers were synthesized from isophorone diisocyanate(IPDI), poly (tetramethylene glycol)(PTMG) and dimethylol propionic acid(DMPA). Subsequently, waterborne polyurethanes were prepared by capping the NCO groups of polyurethane prepolymers with different types of silane coupling agents, such as methyltrimethoxysilane(MTMS), glycidoxypropyl trimethoxysilane(GPTMS), methacryloxypropyl trimethoxysilane (MPTMS) and aminopropyl triethoxysilane(APS). The average particle size of the waterborne polyurethane solutions was increased by adding silane coupling agents. Also, the coating films prepared from GPTMS, MPTMS and APS, exhibited better pencil hardness than those from pure waterborne polyurethane. On the other hand, the coating films from MTMS did not show an improved pencil hardness than those from pure waterborne polyurethane.

• The Korean Journal of Pharmacology
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• v.30 no.2
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• pp.167-179
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• 1994

Recent evidence indicates that glial cells have a wide range of funtions which are critical for maintaining a balanced homeostatic environment in the central nervous system(CNS) peripheral nervous system(PNS). Morever, astrocytes are known to participate in the tissue repair and neuroimmunologic events within the CNS through many kinds of growth factors and cytokines. We investigated the effect of $TGF\;{\beta}_1$, on the growth and biochemical changes of rat glial cells in culture. The proliferative effect was determined by $^3H-thymidine$ uptake and the double immunostain with anti-cell-specific marker and anti-Bromodeoxyuridine(BrdU) antibody. To check the effect of biochemical changes we compared the amounts of glial fibrillar acidic protein(GFAP) and the activity of glutamine synthetase(GS) in astrocyte. And the amounts of myelin basic protein and the activity of 2',3'-cyclic nucleotide phosphohydrolase(CNPase) were measured in oligodendrocyte and the amounts of peripheral myelin in Schwann cell. When $TGF\;{\beta}_1$, was treated for 2 days with cultured glial cell, $TGF\;{\beta}_1$, decreased the $^3H-thymidine$ uptake and proliferation index of double immunostain of astrocytes, which indicates the inhibition of astroglial DNA synthesis, but stimulated the growth of Schwann cell. Also, $TGF\;{\beta}_1$, decrease the GS activity and increased the amounts of GFAP in astrocyte. In the case of Schwann cells the amounts of peripheral myelin was increased when treated with $TGF\;{\beta}_1$. However, $TGF\;{\beta}_1$, didn't show any effect on the proliferation and biochemical changes in oligodendrocyte. These results suggest that $TGF\;{\beta}_1$, might have a critical action in the regulation of proliferation and biochemical changes in glial cells, especially astrocyte.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.365-368
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• 2003

Hair follicles develop as a result of epithelial-mesenchymal interactions between epidermal keratinocytes and dermal cells. Moreover hair follicles constitute multiple cells that influence hair follicle development and cyclic activity. We isolated some cells using explantation and enzymatic digestion method from human scalp hair follicles. So we could culture some follicular cells, such as outer root sheath (ORS) cells, dermal papilla (DP) cells, dermal sheath (DS) cells, matrix cells and melanocyte.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.359-362
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• 2003

The recent development of methods for culturing hair follicles in vitro has proved an important tool to investigate many aspects of drug screening. Human hair follicle is composed of multiple types of cells, whose interactions regulate morphology and cycling-anagen, catagen, and telogen. Many investigators have tried to develop models to prolong of the period of hair elongation in vitro. However these are limited in submerged culture, which don't work due to the lack of cell-cell interactions which are abundant in vivo environment. So we applied dermal equivalent (DE) to culturing flair follicles to prolong hair growth period.

• KSBB Journal
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• v.26 no.3
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• pp.255-259
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• 2011

This study was to suggest the method for wrinkle improvement using Mugil cephalus extract. In order to evaluate the cosmetic product made of M. cephalus extract, the experiments were conducted with subjects and skin states for 4 weeks. Effect of cosmetics containing M. cephalus extract on the water holding capacity and evaporation of the women skin were investigated. The water holding capacity was increased after 1 h of application. But after 2 h, it was decreased. In the case of the water evaporation, it was increased with the increase of time. On the clinical trial, it was also found that water, oil, and rough level on the women skin were increased and wrinkles were improved. Side effects were also not detected during the application and treatment of cosmetics. Based on this result, the application of M. cephalus extract had positive effects on the improvement of wrinkles and skin in women. Therefore, it will be used to develop the wrinkle improvement therapy for women.

• KSBB Journal
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• v.26 no.3
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• pp.260-265
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• 2011

This study aimed to examine the treatment effect of Muraenesox cinereus extract product combined with high frequency on men's damaged skin. The subjects were treated by a product containing M. cinereus extract combined with high frequency therapy for six weeks and tested in skin condition. First, for moisture level change, there was no significant difference between the control group treated only by high frequency therapy and the experimental group treated by a M. cinereus extract product combined with high frequency therapy. But the subjects who increased consistently in moisture level in the cheek and chin were more common in the experimental group. Second, for an oil level, prominently high increase was found in both the control group and the experimental group. Finally, for a rough level, while there was little difference in the control group between immediately after peeling and after six weeks, high improvement effect on a curve was found in the experimental group. Based on this result, cosmetics using M. cinereus extract may have a positive effect on men's skin which is exposed to several stress factors. Accordingly, this result will contribute to developing men's functional cosmetics.

• Journal of Microbiology and Biotechnology
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• v.21 no.2
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• pp.204-211
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• 2011

To yield high concentrations of protein expressed by genetically modified Escherichia coli, it is important that the bacterial strains are cultivated to high cell density in industrial bioprocesses. Since the expressed target protein is mostly accumulated inside the E. coli cells, the cellular product formation can be directly correlated to the bacterial biomass concentration. The typical way to determine this concentration is to sample offline. Such manual sampling, however, wastes time and is not efficient for acquiring direct feedback to control a fedbatch fermentation. An E. coli K12-derived strain was cultivated to high cell density in a pressurized stirred bioreactor on a pilot scale, by detecting biomass concentration online using a capacitance probe. This E. coli strain was grown in pure minimal medium using two carbon sources (glucose and glycerol). By applying exponential feeding profiles corresponding to a constant specific growth rate, the E. coli culture grew under carbon-limited conditions to minimize overflow metabolites. A high linearity was found between capacitance and biomass concentration, whereby up to 85 g/L dry cell weight was measured. To validate the viability of the culture, the oxygen transfer rate (OTR) was determined online, yielding maximum values of 0.69 mol/l/h and 0.98mol/l/h by using glucose and glycerol as carbon sources, respectively. Consequently, online monitoring of biomass using a capacitance probe provides direct and fast information about the viable E. coli biomass generated under aerobic fermentation conditions at elevated headspace pressures.

• Journal of Microbiology and Biotechnology
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• v.16 no.7
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• pp.1032-1040
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• 2006

Some Pseudomonas species can grow on styrene as a sole carbon and energy source. From the new isolate Pseudomonas putida SN1, the genes for styrene catabolism were cloned and sequenced. They were composed of four structural genes for styrene monooxygenase (styA and styB), styrene oxide isomerase (styC), and phenylacetaldehyde dehydrogenase (styD), along with two genes for the regulatory system (styS and styR). All the genes showed high DNA sequence (91% to 99%) and amino acid sequence (94% to 100%) similarities with the corresponding genes of the previously reported styrene-degrading Pseudomonas strains. A recombinant Escherichia coli to contain the styrene monooxygenase from the SN1 was constructed under the control of the T7 promoter for the production of enantiopure (S)-styrene oxide, which is an important chiral building block in organic synthesis. The recombinant E. coli could convert styrene into an enantiopure (S)-styrene oxide (ee >99%) when induced by IPTG The maximum activity was observed as 140 U/g cell, when induced with 1 mM IPTG at $15^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.28 no.9
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• pp.1447-1456
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• 2018

The amylosucrase encoding gene from Deinococcus geothermalis DSM 11300 (DgAS) was codon-optimized and expressed in Escherichia coli. The enzyme was employed for biosynthesis of three different dihydroxybenzene glucosides using sucrose as the source of glucose moiety. The reaction parameters, including temperature, pH, and donor (sucrose) and acceptor substrate concentrations, were optimized to increase the production yield. This study demonstrates the highest ever reported molar yield of hydroquinone glucosides 325.6 mM (88.6 g/l), resorcinol glucosides 130.2 mM (35.4 g/l) and catechol glucosides 284.4 mM (77.4 g/l) when 400 mM hydroquinone, 200 mM resorcinol and 300 mM catechol, respectively, were used as an acceptor substrate. Furthermore, the use of commercially available amyloglucosidase at the end of the transglycosylation reaction minimized the gluco-oligosaccharides, thereby enhancing the target productivity of mono-glucosides. Moreover, the immobilized DgAS on Amicogen LKZ118 beads led to a 278.4 mM (75.8 g/l), 108.8 mM (29.6 g/l) and 211.2 mM (57.5 g/l) final concentration of mono-glycosylated product of hydroquinone, catechol and resorcinol at 35 cycles, respectively, when the same substrate concentration was used as mentioned above. The percent yield of the total glycosides of hydroquinone and catechol varied from 85% to 90% during 35 cycles of reactions in an immobilized system, however, in case of resorcinol the yield was in between 65% to 70%. The immobilized DgAS enhanced the efficiency of the glycosylation reaction and is therefore considered effective for industrial application.

• Nutritional Sciences
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• v.6 no.2
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• pp.113-117
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• 2003

Possible correlations between nutrient intake add health status-as assessed by anthropometric measurements, physical performance and biochemical measurements-were investigated, using 514 healthy young men aged 20 years old who had no apparent health problems. The intakes of nutrients were estimated using a three-day dietary recall method. Height and body weight were measured, and body mass index (BMI) was calculated. Physical performance was tested using sit-ups, push-ups, a loom sprint and a 1,500m run. When compared with the Korean recommended dietary allowances (Korean RDA), the subjects nutrient intakes were adequate except for calcium. The intake of calcium was 516.66$\pm$293.43mg/day, which is 73.80 % of the Korean RDA. The subjects averaged 174.51$\pm$7.07cm in height, 68.17$\pm$9.25 kg in body weight and 22.23$\pm$2.16 in BMI. The associations between nutrient intakes and anthropometric measurements, and between nutrient intakes and physical performance, were weak. The intake of vegetable fat was positively correlated to body weight, whereas the intake of carbohydrate was negatively correlated to BMI. The intake of carbohydrate was positively correlated to the level of performance in the loom sprint, and the intake of vegetable Int was positively correlated to the level of performance of sit-ups. No correlation was found between nutrient intakes and the following biochemical measurements of the blood: the levels of glucose, total protein, total cholesterol, triglyceride, hemoglobin and hematocrit. These results suggest that anthropometric measurements and level of physical performance can be associated with energy nutrient intakes, even in moderately active, well-nourished, young men. No correlation was found between nutrient intake and biochemical measurements, probably because all subjects had a reasonably well-balanced diet.