• Macromolecular Research
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• v.17 no.12
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• pp.1032-1038
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• 2009

A polypyrrole (PPy)/alumina composite filler prepared via in-situ polymerization of pyrrole on alumina particles was incorporated into $Nafion^{(R)}$ to improve the performance of ionic polymer-metal composite (IPMC) actuators. The IPMCs with the pristine PPy without alumina support did not show bending displacements superior to that of the bare Nafion-based IPMC, except at a high PPy content of 4 wt%. This result was attributed to the low redox efficiency of the PPy alone in the IPMC and may have also been related to the modulus of the IPMC. However, at the optimized filler contents, the cyclic displacement of the IPMCs bearing the PPy/alumina filler was 2.2 times larger than that of the bare Nafion-based IPMC under an applied AC potential of 3 Vat 1 Hz. Even under a low AC potential of 1.5 V at 1 Hz, the displacement of the PPy/alumina-based IPMCs was a viable level of performance for actuator applications and was 2.7 times higher than that of the conventional Nafion-based IPMC. The generated blocking force was also improved with the PPy/aiumina composite filler. The greatly enhanced performance and the low-voltage-operational characteristic of the IPMCs bearing the PPy/alumina filler were attributed to the synergic effects of the neighboring alumina moiety near the PPy moiety involving electrochemical redox reactions.

• BMB Reports
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• v.48 no.8
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• pp.461-466
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• 2015

Epigallocatechin gallate (EGCG) and curcumin are well known to naturally-occurring anticancer agents. The aim of this study was to verify the combined beneficial anticancer effects of curcumin and EGCG on PC3 prostate cancer cells, which are resistant to chemotherapy drugs and apoptosis inducers. EGCG showed weaker inhibitory effect on PC3 cell proliferation than two other prostate cancer cell lines, LNCaP and DU145. Co-treatment of curcumin improved antiproliferative effect of EGCG on PC3 cells. The protein expressions of p21 were significantly increased by the co-treatment of EGCG and curcumin, whereas it was not changed by the treatment with each individual compound. Moreover, treatments of EGCG and curcumin arrested both S and G2/M phases of PC3 cells. These results suggest that the enhanced inhibitory effect of EGCG on PC3 cell proliferation by curcumin was mediated by the synergic up-regulation of p21-induced growth arrest and followed cell growth arrest. [BMB Reports 2015; 48(8): 461-466]

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.99-107
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• 1998

Numerous studies have demonstrated a negative association between cigarette smoking and Parkinson's disease. The present study was undertaken to investigate whether chronic exposure of mice to cigarette smoke a(footed the metabolism of 1-methyl-1113,6-tetrahydro-pyridine (MPTP) by cytochrome P4SO (P-450) or flavin-containing monooxygenase (FMO) in the hepatic microsomes of C57BL6/J mice. Adult male C57BL6/J mice were exposed to mainstream smoke generated from 15 cigarettes for 10 min a day and 5 day per week for 6 weeks. MPTP (10 mg/kg body weight) was administered to mice by subcutaneous injection for 6 consecutive days. Microsolnal P-450 content was increased by MPTP, smoke exposure, or both, but NADPH cytochrome P-450 reductase activity was rather decreased by the same treatments. The activities of benzo(a)pyrene hydroxylase, 7-ethoxycoumarin O-deethylase and ethoxyresorufin O-deethylase were significantly increased by the exposure of cigarette smoke, but were not or little affected by MPTP treatment. Benzphetamine N-demethylase activity was not affected either by MPTP treatment or by cigarette smoke exposure, but it was significantly increased by the combined MPTP treatment with cigarette smoke exposure, showing their synergic effect for the induction of the enzyme activity. Interestingly, in vitro studies of hepatic FMO and P-450 system both O-oxygenation and N-demethylation of MPTP were increased in the smoke-exposed or in the MPTP-treated mice. These results suggest that the enhancement in the N-demethylation as well as O-deethylation of P-450 system and in the N-oxygenation of FMO activity by cigarette smoke exposure in mouse liver may contribute to attenuating the neurotoxic effects of MPTP on the nigrostriatal dopaminergic neurons.

• Herbal Formula Science
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• v.17 no.2
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• pp.85-98
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• 2009

The fruits of Schisandra chinensis and Prunus mume have been traditionally used in the Oriental countries as an astringent against diarrhea and abdominal pain, a protectant for liver disease, an antimicrobial, and a blood tonic. However, little is known about the extract of Schizandrae Fructus and Mume Fructus (SMF-Ex) on dextran-sulfate sodium (DSS)-induced colitis in mice. In this study, we investigated the protective effects of SMF-Ex on DSS-induced colitis in mice. An experimental colitis was induced by daily treatment with 5% DSS. SMF-Ex was orally administrated the single dose (80 mg/kg, body weight/day) for 7 days with one time per day. SMF-Ex reduced significantly clinical sign of DSS-induced colitis, including body weight loss, shorten colon length, increased disease activity index (DAI), and histological colon injury. SMF-Ex also inhibited significantly nitric oxide (NO) and prostaglandine $E_2$ ($PGE_2$) productions in DSS-induced colitis mice. Furthermore, SMF-Ex increased significantly an superoxide anion (SOD), catalase, and glutathione peroxidase (Gpx) activity of the colon tissue in DSS-induced colitis mice. These results suggest that SMF-Ex administration could reduce significantly the clinical signs and inflammatory mediators, and increase antioxidant activity in DSS-induced colitis model mice and is a good candidate for further evaluation as an effective anti-ulcerative agent.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.374-378
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• 2004

One hundred and twenty crossbred pigs [(Duroc$\times$Yorkshire)$\times$Landrace] were used to determine the effects of plant extract (PE) supplementation on performance and blood characteristics in weaned pigs fed a corn-dried whey-SBM based diet. Treatments were 1) NC (antibiotic free basal diet), 2) PC (NC diet+100 ppm apramycin and 100 ppm oxytetracycline), 3) PE 0.1 (NC diet+0.1% plant extract), 4) PE 0.2 (NC diet+0.2% plant extract) and 5) PE+AB (PC diet+0.1% plant extract). Through the entire experimental period, ADG of pigs fed PC (300 vs. 281 g/d), PE 0.2 (310 vs. 281 g/d) and PE+AB (306 vs. 281 g/d) diets was higher than that of pigs fed NC diet (p<0.05). However, no differences were found among the treatments for ADFI and gain/feed. At day 2 after the onset of the experiment, fecal consistency score of pigs fed PC, PE 0.1, PE 0.2 and PE+AB diets was lower than that of pigs fed NC diet. There were no significant differences in red blood cell, white blood cell, lymphocytes, neutrophils and monocytes concentrations of blood among the treatments. In conclusion, PE can be used to replace antibiotics in diets for weaned pigs without negative affects on performance. Optimal PE levels seemed to be 0.2% and the results obtained point out to a synergic effect of the combination of PE and antibiotic on performance in weaned pigs.

• Microbiology and Biotechnology Letters
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• v.43 no.1
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• pp.16-21
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• 2015

In this study, a facile two-step pretreatment method was investigated for producing fermentable sugars. Rice straw was pretreated using electron beam irradiation (EBI) and 4-methylmorpholine-N-oxide (NMMO) prior to enzymatic hydrolysis. In the first stage, the EBI on the rice straw was carried out at various doses (100, 300, 500 kGy) and then, irradiated rice straw was stirred with NMMO solution at 120°C for 1 h for the second stage. The pretreated rice straw was hydrolyzed by cellulase 1.5 L (70 FPU/ml) and Novozyme-188 (40 CbU/ml) at 50°C for 24, 48, and 72 h. A sugar yield of 83.8% was obtained from the pretreated rice straw after 72 h of enzymatic hydrolysis. Also, FTIR and XRD results indicate that the pretreatment of the rice straw was effective due to the synergic effects of the two-step pretreatment. In conclusion, rice straw might be a potential substrate for bioethanol production by yeast fermentation.

• Analytical Science and Technology
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• v.23 no.5
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• pp.429-436
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• 2010

The present research evaluates the efficiency of mixed resins between anion exchange resin and active carbon. We expected synergic effect from advantages of both adsorbents. Especially, this research focused on the removal of high cencentrated perchlorate ion from demilitarization solution. The total amount of the adsorbed perchlorate ion is increased considerably with mixed resins between mono functional anion exchange resin and granular active carbon from a single adsorbent. Results demonstated that this process not only improve the efficiency of adsorbing perchlorate, but save the time, space and cost for treating perchlotrate waste solution, because of reducing organic contaminant removing process. The interference effects from coexisting anions are not significant and can successfully applied to real demilitarization sample.

• Molecules and Cells
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• v.39 no.2
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• pp.129-135
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• 2016

Eukaryotic translation initiation factor 2 alpha ($eIF2{\alpha}$), which is a component of the eukaryotic translation initiation complex, functions in cell death and survival under various stress conditions. In this study, we investigated the roles of $eIF2{\alpha}$ phosphorylation in cell death using the breast cancer cell lines MCF-7 and MCF-7/ADR. MCF-7/ADR cells are MCF-7-driven cells that have acquired resistance to doxorubicin (ADR). Treatment of doxorubicin reduced the viability and induced apoptosis in both cell lines, although susceptibility to the drug was very different. Treatment with doxorubicin induced phosphorylation of $eIF2{\alpha}$ in MCF-7 cells but not in MCF-7/ADR cells. Basal expression levels of Growth Arrest and DNA Damage 34 (GADD34), a regulator of $eIF2{\alpha}$, were higher in MCF-7/ADR cells compared to MCF-7 cells. Indeed, treatment with salubrinal, an inhibitor of GADD34, resulted in the upregulation of $eIF2{\alpha}$ phosphorylation and enhanced doxorubicin-mediated apoptosis in MCF-7/ADR cells. However, MCF-7 cells did not show such synergic effects. These results suggest that dephosphorylation of $eIF2{\alpha}$ by GADD34 plays an important role in doxorubicin resistance in MCF-7/ADR cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.3
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• pp.753-759
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• 2005

In order to evaluate the in vivo synergic effect of Eunkyo-san with quinolone antibiotics, rufloxacin (RUFX), the viable bacterial numbers and histopathological changes were monitored after experimental respiratory infection with Klebsiella peumoniae NCTC 9632. The obtained results were as follows : In RUFX group, the viable bacterial numbers were significantly decreased compared to those of control group and these were more dramatically decreased compared to those of single treatment with RUFX, respectively in concomitant treated groups with Eunkyo-san. In control group, severe infiltration of inflammatory cells, hemorrhage and hypertrophy of alveolar linings were demonstrated at microscopical levels. However, these abnormal histopathological changes were significantly decreased compared to those of control group in RUFX group, and these were more dramatically decreased compared to those of single treatment with RUFX, respectively in concomitant treated groups with Eunkyo-san. In RUFX group, the LSA% (luminal surface of alveolar%) were significantly increased compared to those of control group and these were more dramatically decreased compared to those of single treatment with RUFX, respectively in concomitant treated groups with Eunkyo-san. According to these results, it is considered that in vivo antibacterial activity of RUFX group was dramatically increased by concomitant use of Eunkyo-san against K. pneumoniae NCTC 9632 infection of respiratory tract.

• Journal of Digital Convergence
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• v.15 no.1
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• pp.163-170
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• 2017

The purposes of this study is to examine the effect of fitness among entrepreneurship, dynamic capabilities and innovation activities on business performance. A survey was conducted and analyzed on small & medium manufacturing companies in Korea with the following result of the study. First, the fitness of entrepreneurship and dynamic capabilities, the fitness of dynamic capabilities and innovation activities, the fitness of entrepreneurship and innovation activities have a significant effect on business performance respectively. Second, the fitness of all the three variables also has a significant positive effect on the performance. Additional path analysis shows that dynamic capabilities and innovation activities have mediating roles between entrepreneurship and business performance. The results imply that not only each of the entrepreneurship, dynamic capabilities, and innovation activities has a positive effect on business performance but also the three factors in harmony have a synergic positive effect on the business performance.