• 제목/요약/키워드: synergism

검색결과 242건 처리시간 0.142초

Cytokine Synergism in Apoptosis: Its Role in Diabetes and Cancer

  • Lee, Myung-Shik
    • BMB Reports
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    • v.35 no.1
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    • pp.54-60
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    • 2002
  • The effects of individual cytokine on apoptosis have been extensively studied. However, the effect of the cytokine combination, or the synergistic effect of cytokines on cell death, has not been widely studied, though synergism between cytokines has been documented in a variety of biological situations. In our effort to identify the final death effector molecule(s) in autoimmune diabetes, we inadvertently became interested in the cytokine synergism. We discovered that $IFN{\gamma}/TNF{\alpha}$ synergism, rather than the Fas ligand as currently believed, is responsible for the apoptosis of pancreatic islet cells both in vitro and in vivo. We also studied similar cytokine synergism in cancer cell deaths, and noted the similarities and dissimilarities between cancer cell death and islet cell death.

방염 폴리에스테르 섬유의 열적거동 (II) -브롬화합물/산화안티몬의 상승작용- (Thermal Behavior of Flame-Retardant Polyester Fibers (II) -Synergism of Bronline Compounds/Antimony Trioxide-)

  • 이의소;송경근;고석원
    • 한국섬유공학회지
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    • v.28 no.5
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    • pp.62-67
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    • 1991
  • This study was undertaken to elucidate bromine-antimon Synergism of the Polyester fabrics treated with a mixture of organobromine compounds/antimony trioxide. For this purpose fide aromatic bromine compounds with a relatively high bromine content such as DBDPO, OB-DPO, HBCD, PBT, and HBB were chosen. Polyester fabrics were treated with the aqueous dispersion solution of a mixture of bromine compounds/antimony trioxide together with binder. Bromine-antimony synergism was confirmed by plotting the LOI values against bromine/antimony weight ratio. Bromine-antimony synergism was inferred by comparing thermogravimetric and differential thermal analysis curves of a mixture of bromine compounds/antimony trioxide with those combined mathematically from thermogravimetric and differential thermal analysis curves of bromine compounds and antimony trioxide, respectively.

Antioxidation synergism between ZnDTC and ZnDTP in mineral oil

  • Du, Da-Chang;Kim, Seock-Sam;Chun, Jung-Sik;Kwon, Wan-Seop;Suh, Chang-Min
    • 한국윤활학회:학술대회논문집
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    • pp.305-312
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    • 2001
  • Antioxidation synergism between ZnDTC and ZnDTP in a kind of mineral base oil was investigated by RBOT. The results indicate that there is antioxidation synergism between the two additives. FTIR analysis show that the oxidation products in the tested oils containing the two additives are much less than those in the tested oils containing the single additive alone.

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Synergism among Endo-xylanase, $\beta$-Xylosidase, and Acetyl Xylan Esterase from Bacillus stearothermophilus

  • Suh, Jung-Han;Choi, Yong-Jin
    • Journal of Microbiology and Biotechnology
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    • v.6 no.3
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    • pp.173-178
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    • 1996
  • Synergic effects among endo-xylanase, $\beta$-xylosidase, and acetyl xylan esterase of Bacillus stearothermophilus in the hydrolysis of xylan were studied by using birchwood, oat spelt, and acetylated xylan as substrates. Synergism between endo-xylanase and $\beta$-xylosidase was observed on all three substrates tested, indicating that $\beta$-xylosidase enhanced the production of xylose by relieving the end-product inhibition upon endo-xylanase conferred by xylooligomers. Endo-xylanase and $\beta$-xylosidase also showed synergism with acetyl xylan esterase in the hydrolysis of birchwood and acetylated xylan, while no synergic effect was detected in oat spelt xylan hydrolysis. Thus, the hydrolysis of xylan containing acetic acid side chains required the action of acetyl xylan esterase, which eliminated the steric hindrance of the side chains, leading to the better hydrolysis by endo-xylanase and $\beta$-xylosidase , and the acetyl xylan esterase activity was also enhanced by endo-xylanase and $\beta$-xylosidase for the latter enzymes provided acetyl xylan esterase with shorter xylan oligomers, the better substrate for the enzyme.

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Synergism effect of mixed surfactant solutions in remediation of soil contaminated with PCE

  • Lee, Dal-Heui
    • 한국지하수토양환경학회:학술대회논문집
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    • pp.47-51
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    • 2004
  • The purpose of this research was to evaluate the effect of mixed surfactant solution for removal of perchloroethylene (PCE) in soil. Ten different surfactant solutions were used in column studies. Mixed surfactant solutions (anionic and nonionic) were most effectively worked in the sandy soil for removal of PCE as a result of synergism between the two types of surfactants. The effectiveness of the mixture of surfactants was 35 % greater than that for the anionic or nonionic surfactant alone. The results indicate that mixed surfactant solution leaching is a promising candidate for the remediation of PCE contaminated sandy soil.

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Activity of Essential Oil from Mentha piperita against Some Antibiotic-Resistant Streptococcus pneumoniae Strains and Its Combination Effects with Antibiotics

  • Choi, Sung-Hee;Shin, Seung-Won
    • Natural Product Sciences
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    • v.13 no.2
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    • pp.164-168
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    • 2007
  • To investigate natural antibiotics from plant essential oils and to evaluate their synergism with current antimicrobial drugs in inhibiting antibiotic-resistant strains of Streptococcus pneumoniae. The minimal inhibitory concentrations (MICs) of eleven plant essential oils and their main components were established for two antibiotic-susceptible and two antibiotic-resistant strains of S. pneumoniae, using broth microdilution tests. Potential synergism with oxacillin, norfloxacin, or erythromycin was evaluated using a checkerboard microtitre assay. Among the tested oils, Mentha piperita oil and its main component, menthol, exhibited the strongest inhibitory activities against all of the tested strains. The activity of antibiotics against antibiotic-resistant strains of S. pneumoniae was enhanced significantly by combination with Mentha piperita oils and its main component, menthol. In conclusion, the combination Mentha piperita essential oil or menthol with antibiotics could be used to reduce the effective dose of antibiotic and to modulate the resistance of S. pneumoniae strains.

Magnolol 및 Honokiol의 항생제와의 병용 효과 (Antibacterial Activity of Magnolol and Honokiol in Combination with Antibiotics)

  • 정경수;이수나;김영호;배기환
    • 생약학회지
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    • v.31 no.4
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    • pp.407-411
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    • 2000
  • Antibacterial activities of magnolol (MGL) and honokiol (HKL) in combination with four representative antibiotics-amoxicillin (AMPC), oxytetracyclin (OTC), gentamicin (GM) and chloramphenicol (CAP)-were evaluated against four bacterial strains. When tested by disk-plate method, five out of eight combinations such as HKL-AMPC, HKL-CAP, MGL- AMPC, MGL-OTC, and MGL-CAP showed additive to synergistic interaction against gram- negative bacterium Salmonella typhimureum. Of these, MGL-AMPC combination turned out to be antagonistic against Sarcina lutea and Bacillus thurungiensis. Against these two grain-positive bacteria, only HKL-GM combination showed additivity to synergism. All the other combinations showed no interactions. Despite these results, however, no synergism was observed in checkerboard titration assay.

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Essential Oil Compounds from Agastache rugosa as Antifungal Agents Against Trichophyton Species

  • Shin, Seung-Won
    • Archives of Pharmacal Research
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    • v.27 no.3
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    • pp.295-299
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    • 2004
  • The antifungal activities of the essential oil from Agastache rugosa and its main component, estragole, combined with ketoconazole, one of the azole antibiotics commonly used to treat infections caused by Trichophyton species, were evaluated in this study. The combined effects were measured by the checkerboard microtiter and the disk diffusion tests, against T. erinacei, T. mentagrophytes, T. rubrum, T. schoenleinii and T. soudanense. Susceptibility of the five Trichophyton species to the oil alone, or ketoconazole alone, differed distinctly. The fractional inhibitory concentration indices (FICI) of ketoconazole combined with estragole or A. rugosa essential oil, against the tested Trichophyton species, were between 0.05 and 0.27, indicating synergistic effects. These drug combinations exhibited the most significant synergism against T. mentagrophytes, with FICIs of 0.05 and 0.09 for estragole and the essential oil fraction from A. rugosa, respectively. Isobolograms based on the data from checkerboard titer tests also indicated significant synergism between ketoconazole and the Agastache oil fraction or estragole, against the Trichophyton species evaluated. Trichophyton susceptibility to ketoconazole was significantly improved by combination with the Agastache rugosa oil fraction or its main component, estragole.

수종의 세균공존에 의한 Furfural의 분해 (Symbiotic Biodegradation of Furfural by Some Bacteria)

  • 한홍의;홍순우;하영칠
    • 미생물학회지
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    • v.17 no.4
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    • pp.198-202
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    • 1979
  • Pseudomonas sp. 세균주와 Zoogloea sp. 한 균주를 토양에서 분리하였으며 이들 균주는 furfural로부터 전환된 2-furoic acid와 primary amine group을 포함한 어떤 물질을 매개체로 이용함으로서 상호간에 procooperation과 Synergism을 보여 주었다. 이에 의하여 furfural이 완전히 산화됨과 동시에 탈색이 되는데 그 효과는 단일균주보다 혼합배양이 보다 효고적이었다.

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Trichoderma viride와 Penicillium funiculosum Cellulase 성분효소 간의 상승작용에 관한 연구 (Cross-Synergistic Interactions between Trichoderma viride and Penicillium funiculosum Cellulase)

  • Hong, Jeong-Hwa
    • 한국식품영양과학회지
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    • v.22 no.3
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    • pp.340-348
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    • 1993
  • Penicillium funiculosum과 Trichoderma viride cellulase의 정제효소들을 사용하여 cross-synergism을 조사하였다. Exo-exo형 상승작용이 Avicel을 분해하는데 가장 효과적이었으며 exo-endo형은 다소 효과가 떨어졌다. 정제효소성분과 이종의 조효소를 혼합하여 70시간 이상 Avicel을 가수분해하며 생성된 total sugar를 측정한 결과, P. funiculosum cellulase에서 분리정제한 $\beta$-glucosidase 성분효소는 T. viride cellulase와 상승작용을 크게 나타내며 Avicel을 가수분해하였다. 또한, T. viride cellulase에서 분리정제한 exoglucanase 성분효소도 P. funiculosum cellulase의 가수분해능을 크게 향상시켰다. 이와같은 결과로 미루어 볼 때, 이종의 cellulase로 부터 부족한 성분효소를 보충시켜 효소성분비율을 변화시킴으로써 Avicel의 가수분해도를 향상시킬 수 있을 것으로 사료된다. 이 때 최대한 높은 가수분해를 얻기 위하여 여러 형식의 상승작용이 같이 이루어져야할 것이다.

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