• 한국연소학회:학술대회논문집
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• 2002.11a
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• pp.123-128
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• 2002

The synergistic effect of ethylene/propane and ethylene/methane mixtures on soot formation is studied experimentally with a concentric co-flow burner. The integrated soot volume fractions, laser light scattering signal and PAH concentrations are measured for different fuel supply configurations. The synergistic effect in ethylene/propane diffusion flames is found to be affected not only by the composition of mixture but also by the way of mixing. Comparing to the homogeneously mixed ethylene/propane case, the increase of soot formation is observed when propane is supplied through the inner nozzle, while the decrease is observed when propane is supplied through the outer nozzle. However, the measured PAH concentration distributions are inconsistent with the current view of the synergistic effect of ethylene./propane mixture on soot formation. Virtually no synergistic effect is observed in ethylene-methane flames regardless of the fuel supply configuration, which suggests the important role of $C_3$ species produced during the propane pyrolysis process for the synergistic effect.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1039-1046
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• 2005

The salt resistance of antibacterial activity and synergistic effect with clinically used antibiotic agents are critical factors in developing effective peptide antibiotic drugs. For this reason, we investigated the resistance of antibacterial activity to antagonism induced by NaCl and $MgCl_2$ and the synergistic effect of P20 with cefotaxime. P20 is a 20-residue synthetic peptide derived from a cecropin A (CA)-melittin(ME) hybrid peptide. In this study, P20 was found to have potent antibacterial activity against clinically isolated methicillin-resistant Staphylococcus aureus (MRSA) strains without hemolytic activity against human erythrocytes. The combination study revealed that P20 in combination with cefotaxime showed synergistic antibacterial activity in an energy-dependent manner. We also confirmed the synergism between P20 and cefotaxime by fluorescence-activated flow cytometric analysis by staining bacterial cells with propidium iodide (PI) and bis-(1,3-dibutylbarbituric acid) trimethine oxonol (BOX). This study suggests that P20 may be useful as a therapeutic antibiotic peptide with synergistic effect in combination with conventional antibiotic agents.

• Journal of the Korean Wood Science and Technology
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• v.50 no.1
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• pp.12-30
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• 2022

Many studies on plant extracts have been reported for the treatment of candidiasis caused by Candida albicans, a representative fungal infection. This study demonstrates the synergistic antifungal activity of the combination of Phellodendri Cortex and Magnoliae Cortex, previously reported to have antifungal efficacy. Considering the antifungal efficacy and the separation of the active constituents, berberine and magnolol, hot water extraction and carbon dioxide supercritical extraction were selected for Phellodendri Cortex and Magnoliae Cortex, respectively. A combination of 0.55 g/L hot water extract of Phellodendri Cortex and 0.59 g/L carbon dioxide supercritical extract of Magnoliae Cortex showed synergistic antifungal activity. The synergistic antifungal activity of 160 μM berberine and 100 μM magnolol, which are representative antifungal compounds of Phellodendri Cortex and Magnoliae Cortex, respectively, contributes to the synergistic antifungal effect of their extracts. The additive decrease in cellular ergosterol level and the increased antifungal efficacy by extracellular ergosterol suggest that disruption of the biological function of ergosterol in the cell membrane is not responsible for the synergistic antifungal activity of berberine and magnolol. Synergistic cellular release of chromosomal DNA upon mixing berberine and magnolol indicates that disruption of the cellular structure is responsible for the synergistic antifungal effect of berberine and magnolol.

• Corrosion Science and Technology
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• v.15 no.4
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• pp.171-181
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• 2016

In this work, synergistic corrosion inhibition effect of nitrite and 3 kinds of ethanolamines on ductile cast iron using chemical and electrochemical methods was evaluated. This work attempts to clarify the synergistic effect of nitrite and ethanolamines. The effects of single addition of TEA, DEA, and MEA, and mixed addition of nitrite plus TEA, DEA or MEA on the corrosion inhibition of ductile cast iron in a tap water were evaluated. A huge amount of single addition of ethanolamine was needed. However, the synergistic effect by mixed addition was observed regardless of the combination of nitrite and triethanolamines, but their effects increased in a series of MEA + nitrite > DEA + nitrite > TEA + nitrite. This tendency of synergistic effect was attributed to the film properties and polar effect; TEA addition couldn't form the film showing high film resistance and semiconductive properties, but DEA or MEA could build the film having relatively high film resistance and n-type semiconductive properties. Moreover, it can be explained that this behaviour was closely related to electron attractive group within the ethanolamines, and thus corrosion inhibition power depends upon the number of the electron attractive group of MEA, DEA, and TEA.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.4
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• pp.992-997
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• 2007

Cisplatin is a chemotherapeutic drug which is widely used for cancer therapy including cervical cancer. The purpose of this study is to elucidate synergistic effect of Cisplatin and Berberine on the apoptosis of HeLa cells and to determine whether oxidants are formed as part of apoptotic process. Apoptotic death of HeLa cells by cisplatin and berberine was confirmed by chromatin condensation of HeLa cells and flow cytometric analysis of intracellular ROS(reactive oxygen species) production. In MTT assay, Cell viability was decreased and enhanced ROS generation in combination of cisplatin and berberine significantly, as compared with cisplatin only. Synergistic effect of Cisplatin and Berberine on the inhibition of cell growth by apoptosis was clearly observed and ROS may play an important role in apoptosis. This effect suggest the possibility lowering the concentration of chemotherapeutic drugs, which alleviate the side effect of drugs.

• Journal of Nutrition and Health
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• v.31 no.4
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• pp.739-746
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• 1998

This study was designed to investigated the antitumor effect and change chemosensitivity of chitosan in 2 kinds of humen lung cancer cell lines(NCI-H522, NCI-H596). To evaluate the antitumor effect and synergistic effectof chomosensitivity, MTT assay was used in vitro. then anticancer drugs used were 챤-platin , ectoposide, and adrimycin. The results of this study were as follows; Chitosan shwoed in antitumor effect on both NCI-H522 and NCI-H596. The lung cancer viability percent for NCI-H522 and NCL-H596 showed at the lowest levels of 5.31 and 5.33% when the concentration of chitosan was 25mg/$m\ell$ media and the exposure time of chitosan was 72 hours. ID50 value of chitosan on both NCI-H522 and NCI-H596 showed at the lowest levels of 14.07, 11.68 mg/$m\ell$ media when the exposure time of chitosan was 72 hours. the synergistic effect of chomosensitivity was better in NCI-H596 than in NCI0H522 . When the synergistic effect of chomosensitivity was shown according to the kind of the anticancer drugs, in case of NCI-H522 , in the concentration of 100$\mu\textrm{g}$/$m\ell$, ectoposide showed the highest synergistic effect of chomosensitivity and then was adrimycin In case of NCI-H596, in the concentration of 100$\mu\textrm{g}$/$m\ell$,, the order of the synergistic effect of chomosensitivity was ectoposide>adrimycin>cis-platin and in the concentration of 10$\mu\textrm{g}$/$m\ell$, ectoposide>cis-platin >adrimycin. It is concluded that chitosan is an active antitumor agent and is increased chomosensitivity though there is difference according to the kind and the concentration of anticancer drugs. But to be sued to lung cancer theraphy, further studies on toxicity, the mechanism of action, animal experiment are wanted.

• Journal of the Korean Operations Research and Management Science Society
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• v.36 no.4
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• pp.1-16
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• 2011

It is important not only to introduce the C4I(Command and Control, Communication, Computer, Intelligence) system for realizing the NCW(Network Centric Warfare) but also to evaluate the synergistic effect by the C4I system. However, the study effort for evaluating the system's synergistic effect is insufficient compared with introducing the system. Therefore, in this paper, we proposed a model that measures the synergistic effect of combat power by the warfare information system. To measure the synergistic effect of warfare information system, the network power must be considered, so we also proposed a new methodology for measurement of network power based on SNA(Social Network Analysis), not Metcalfe's law. A model we proposed is a model that measures the raised combat power by the network effectiveness. The methodology and model we proposed in this paper will be used usefully to analyze the practical effect of constructing future warfare information system.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.813-818
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• 2002

Expression of monokine induced by IFN-$\gamma$(Mig) mRNA is well-known to strictly depend on Interferon-$\gamma$(IFN-$\gamma$). Lipopolysaccharide (LPS) alone Is weakly effective on Mig mRNA expression in mouse Peritoneal macrophages. This study was undertaken to investigate the synergistic effect of LPS and IFN-$\beta$ on chemokine Mig gene expression in mouse peritoneal macrophages. Although IFN-$\beta$ alone was minimally effective, LPS plus IFN-$\beta$ synergized to produce a high level of Mig mRNh. The synergistic effect of LPS and IFN-$\beta$ (LPS/IFN-$\beta$) on Mig mRNA expression was strain-specific. The most effective synergistic effect of LPS/IFN-$\beta$ on the mRNh expression was found in simultaneous stimulation of LPS/IFN-$\beta$. This synergy was modulated at the level of the gene transcription and was not dependent on a new protein synthesis. Synergistic effect of LPS/IFN-$\beta$ also required the activation of $NF-_KB$. Accordingly, these data suggest that LPS/IFN-$\beta$ synergizes the expression of Mig mRNA through a process that depends on a pretranscriptional level and/or coincident Mig mRNA transcription.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.953-958
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• 2013

Selaginella tamariscina is a traditional herb used in medicine. Phytochemical amentoflavone, a biflavonoid class of flavonoids, was isolated from the plant of Selaginella tamariscina. In this study, the antibacterial effects and combination effects of amentoflavone and conventional antibiotics such as ampicillin, cefotaxime, and chloramphenicol were investigated. These results showed that amentoflavone had a considerable antibacterial effect and synergistic interaction with antibiotics against various bacterial strains (fractional inhibitory concentration index ${\leq}$ 0.5), except for Streptococcus mutans. To study the mechanism(s) involved in the synergistic activities between amentoflavone and antibiotics, we detected hydroxyl radical formation using 3'-(p-hydroxyphenyl) fluorescein and measured the $NAD^+/NADH$ ratio by $NAD^+$ cycling assay. The results indicated that the formation of hydroxyl radical would be a cause of the synergistic effect and that this oxidative stress originated from a transient NADH depletion. This study suggests that amentoflavone synergizes with antibiotics and has potential as a therapeutic agent for antimicrobial chemotherapy.

• Bulletin of the Korean Chemical Society
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• v.26 no.3
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• pp.423-427
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• 2005

The bis(2,4,4-trimethylpentyl)phosphinic acid (Cyanex-272) and sodium diethyl- dithiocarbamate (NaDDC) ligands were used to extract of metal ions ($Cd^{2+},\;Co^{2+},\;Cu^{2+},\;Pb^{2+},\;Zn^{2+}$) in supercritical $CO_2$. Experiments showed a strong synergistic effect and better extraction efficiency if the two ligands were used together. In-situ UV-visible observation indicates that NaDDC in the water/supercritical $CO_2$ started to decompose slowly. The synergistic effect seems to come from the deprotonation of the organophosphorus ligand by amines from the decomposed NaDDC. The enhancing role of amines was confirmed using the mixture of Cyanex-272 and diethylamine(DEA) in the metal extraction.