• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.4
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• pp.247-252
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• 2000

The strength and regulatory characteristics of the heat-inducible HSA1, HSA2 and TPS1 promoters were compared with those of the well-established, carbon source-regulated FMD promoter in a Hansenula polymorpha-based host system in vivo. In addition, the Saccharomyces cerevisiae-derived ADH1 promoter was analysed. While ADH1 promoter showed to be of poor activity in the foreign host, the strength of the heat shock TPS1 promoter was found to exceed that of the FMD promoter, which at present is considered to be the strongest promoter for driving heterologous gene expression in H. polymorpha.

• Archives of Pharmacal Research
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• v.27 no.6
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• pp.633-639
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• 2004

The expression of therapeutic transgenes in recombinant adenoviral vectors is a major cause of toxicity in dividing cancer cells as well as non dividing normal cells. To solve the problem of toxicity to normal cells, we have reported on a recombinant adenoviral vector system （AdLP-） in which the expression of the transgene is directed by the tumor-specific L-plastin promoter （LP） （Chung et al., 1999）. The object of this study was to generate a recombinant adenoviral vector system which would generate tumor cell specific expression of cytosine deaminase （CD） gene. We report the construction of a replication-incompetent adenoviral vector in which CD is driven by the L-plastin promoter （AdLPCD）. Infection of 293 cells by AdLPCD generated the functional CD protein as measured by HPLC analysis for the conversion of 5-Fluorocy-tosine （5-FC） to 5-Fluorouracil （5-FU）. HPLC analysis in conjunction with counting radioactivity for ［6-$^3$H］-5FC and ［6-$^3$H］-5FU demonstrated vector dose-dependent conversion of 5-FC to 5-FU in AdLPCD infected ovarian cancer cells. The results from present and previous studies（Peng et al., 2001； Akbulut et al., 2003） suggest that the use of the AdLPCD／5-FC system may be of value in the treatment of cancer including microscopic ovarian cancer in the peritoneal cavity.

• Bulletin of the Korean Chemical Society
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• v.35 no.10
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• pp.3025-3029
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• 2014

To realize copper-based electrode materials for printed electronics applications, it is necessary to improve the adhesion strength between conductive lines and the substrate. Here, we report the preparation of Cu pastes using (3-glycidoxypropyl) trimethoxysilane (GPTMS) prepolymer as an adhesion promoter (AP). The Cu pastes were screen-printed on glass and polyimide (PI) substrates and sintered at high temperatures (> $250^{\circ}C$) under a formic acid/$N_2$ environment. According to the adhesion strengths and electrical conductivities of the sintered Cu films, the optimized Cu paste was composed of 1.0 wt % GPTMS prepolymer, 83.6 wt % Cu powder and 15.4 wt % vehicle. After sintering at $400^{\circ}C$ on a glass substrate and $275^{\circ}C$ on a PI substrate, the Cu films showed the sheet resistances of $10.0m{\Omega}/sq$. and $5.2m{\Omega}/sq$., respectively. Furthermore, the sintered Cu films exhibit excellent adhesion properties according to the results of the ASTM-D3359 standard test.

• Journal of Microbiology and Biotechnology
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• v.19 no.3
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• pp.331-337
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• 2009

Interleukin-13 (IL-13) has been proposed as a therapeutic target for bronchial asthma as it plays crucial roles in the pathogenesis of the disease. We developed an in vitro test system measuring transcriptional downregulatory activities on IL-13 as a primary screening method to select drug candidates from natural products. The promoter region of IL-13 (-2,048 to +1) was cloned into the upstream of a luciferase gene in the plasmid pGL4.14 containing the hygromycin resistance gene as a selection marker, generating pGL4.14-IL-13. The EL-4 thymoma and RBL-2H3 mast cells transiently expressing this plasmid highly produced the luciferase activities by responding to PI (PMA and ionomycin) stimulation up to 8-fold and 13-fold compared with the control, respectively, whereas cyclosporin A, a well-known antiasthmatic agent, significantly downregulated the activities. The BF1 clone of RBL-2H3 cells constitutively expressing pGL4.14-IL-13 was established by selecting surviving cells under a constant lethal dose of hygromycin treatment. The feasibility of this system was evaluated by measuring the downregulatory activities of 354 natural products on the IL-13 promoter using the BF1 clone. An extract from Morus bombycis (named TBRC 156) significantly inhibited PI-induced luciferase activities and IL-13 mRNA expression, but not the protein expression. Fisetin (named TBRC 353) inhibited not only PI-induced luciferase activities and mRNA expression, but also the IL-13 protein secretion, whereas myricetin (named TBRC 354) could not suppress the IL-13 expression at all. Our data indicated that this in vitro test system is able to discriminate the effects on IL-13 expression, and furthermore, that it might be suitable as a simple and time-saving primary screening system to select antiasthmatic agents by measuring transcriptional activities of the IL-13 promoter.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.5
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• pp.389-392
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• 2004

In order to produce a harmful protein more efficiently, this expression cassette, dubbed pCol-MICT, is directed by the colicin promoter, and was constructed by the insertion of a $rrnBT_1T_2$ fragment of pEXP7, and a MxelnteinCBD fragment of pTXB3, into pSH375. To test whether harmful proteins, including proteolytic enzymes, could be effectively produced by this cassette, the carboxypeptidase (CPase) Taq gene was inserted into the pCol-MICT cassette to yield pCol-CPase Taq-MICT. E coli W3l 10 tells harboring pCol-CPase Taq-MICT produced a large quantity of this enzyme, as much as 47.2 mg of purified from per liter of culture, when cultured in the presence of mitomycin C ($0.4{\mu}g/mL$). This indicates that the colicin promoter-controlled E, coli expression cassette was able to produce almost 8 times of protein than the conventional tar promoter-based system, and that this cassette may be useful in the Synthesis of other harmful proteins.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.260-267
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• 2001

The objective of this study was to investigate the characteristics of jet flow and heat transfer caused by trapezoid rods array in impinging jet system. In this study, trapezoid rods have been set up in front of flat plate to serve as a turbulence promoter. The bottom width of trapezoid rod was W=4, 8mm and oblique angle were $80^{\circ}$. The space from rods to the heating surface was C=1, 2, 4mm, the pitch between each rods was P=30, 40, 50mm, and the distance from nozzle exit to flat plate was H=100, 500mm. This results were compared with the case without trapezoid rods. As a result, when rods are installed in front of the impinging plate, the acceleration of the jet flow and the eddies due to the rods seem to contribute to the heat transfer enhancement. Among test conditions, the heat transfer performance was best for the condition of W=8mm, C=1mm, P=30mm and H/B=10. The maximum heat transfer rate is about 1.9 times larger than that without trapezoid rods.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.9
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• pp.904-913
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• 2001

The objective of this study was to investigate the characteristics of jet flow and heat transfer caused by trapezoid rods array in impinging jet system. In this study, trapezoid rods have been set up in front of flat plate to serve as a turbulence promoter. The bottom width of trapezoid rod was W=4, 8 mm and oblique angle were 80$^{\circ}$. The space from rods to the heating surface was C=1, 2, 4 mm, the pitch between each rods was P=30, 40, 50 mm, and the distance from nozzle exit to flat plate was H=100, 500 mm. This results were compared with the case without trapezoid rods. As a result, when rods are installed in front of the impinging plate, the acceleration of the jet flow and the eddies due to the rods seem to contribute to the heat transfer enhancement. Among test conditions, the heat transfer performance was best for the condition of W=8 mm, C=1 mm, P=30 mm and H/B=10. The maximum heat transfer rate is about 1.9 times larger than that without trapezoid rods.

• Journal of Life Science
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• v.12 no.4
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• pp.477-482
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• 2002

As a biological model system for the production of an active antibacterial peptide, we have attempted the expression and secretion of insect defensin in Saccharomyces cerevisiae. Nucleotide sequences encoding mature defensin composed of 40 amino acids were fused in frame with promoter and signal sequence of Saccharomyces diastaticus glucoamylase, and mating factor $\alpha$ l[MF $\alpha$1] prosequence. The host strain, S. cerevisiae 2805 was transformed with the resulting plasmid, pSMFll The secretion of functional defensin was confirmed by growth inhibition zone assay using Micrococcus luteus as a test organism. Insect defensin was secreted to the culture supernatant in biologically active form by glucoamylase signal sequence and mating factor $\alpha$1 prosequence. Most of antibacterial activity was detected in the culture supernatant. Defensin was also active against Staphylococcus aureus and Listeria monocytogenes.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.2
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• pp.117-124
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• 2005

Aluminum plate heat exchanger, rotary wheel heat exchanger, and heat pipe heat exchanger have been used (or ventilation heat recovery in the air-conditioning system. The purpose of this research is to develop high efficiency plastic plate heat exchanger which can substitute aluminum plate heat exchanger. Because thermal conductivity of plastic is quite small compared to that of aluminum, various heat transfer enhancement techniques are applied in the design of plastic plates. Five types of heat exchanger model are designed and manufactured, which are plate type, plate-fin type, turbulent promoter type, corrugate type, and dimple type. Thermal performance and pressure loss of each heat exchangers are measured in various operating conditions, and compared each other. Test results show that heat transfer performance of corrugate type, turbulent promoter type, and dimple type are increases about $43\%$, $14\%$, and $33\%$ at the equivalent fan power compared to those of plate type, respectively. On the other hand, the heat transfer performance of plate-fin type decreases $9\%$ because fins can not play their own role.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.2
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• pp.235-239
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• 2004

Drosophila melanogaster heat shock protein 70 gene promoter (Dhsp70p) is widely used in transgenic insect to drive exogenous gene, and the homologous region 3 from Bombyx mori nucleopolyhedrovirus (BmNPVhr3) functions as an enhancer for several promoters. To test whether BmNPVhr3 can enhance the Dhsp70ps transcriptional activity, the reporter plasmids, which contain the Dhsp70p, the reporter $\beta$-galactosidase gene with SV40 terminator and BmNPVhr3 fragment, are constructed and transfected into the insect cell lines (Bm-N cells and Sf-21 cells) by lipofectin-mediated method. The results from the transient expression assay show that BmNPVhr3 significantly increases transcriptional activity of Dhsp70p both under the normal condition and under the heat-shock treatment, although the effects are significantly different between in Bm-N cells and in sf-21 cells. The enhancing behavior of BmNPVhr3 on the Dhsp70p is in an orientation-independent manner. Meanwhile, the effects of heat-shock treatment on Dhsp70p alone or Dhsp70p/BmNPVhr3 combination present no significant difference, indicating that BmNPVhr3 only enhances the transcriptional activity of Dhsp70p, but cant alter its characteristic of the response to the heat-shock stress. The above results suggest that the Dhsp70p/BmNPVhr3 combination is more effective one to drive exogenous gene for transgene or stable cell expression system in insects.