• Bulletin of the Korean Chemical Society
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• 제29권8호
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• pp.1499-1504
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• 2008

Pyrazine derivatives bind to b-RAF receptor which is important in cancer therapy. The ligand-receptor interactions have been studied by comparative molecular field analysis (CoMFA) and molecular docking methods. Applying conventional ligand-based alignment schemes for the whole set was not successful. However, QM and DFT results suggested that some ligands have electrostatic interaction while others have steric interactions. On the basis of these results, we divided the dataset into two subsets. Electrostatic effect was found to be important in one set while steric effect for the other. Best docking modes were obtained for each subset based on the available crystal structure. These receptor-guided CoMFA models propose an interesting possibility which is difficult to obtain otherwise. i.e., in one binding mode the electrostatic interaction plays a key role for one subset ($q^2$ = 0.46, $r^2$ = 0.98), while in another binding mode steric effect is important with another subset ($q^2$ = 0.43, $r^2$ = 0.74).

• 한국수소및신에너지학회논문집
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• 제28권5호
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• pp.570-576
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• 2017

Gas turbine system with steam injection has shown outstanding advantages such as high specific power and NOx reduction. In the present work, a comparative exergetic analysis was carried out for Steam Injected Gas Turbine (STIG), Regenerative Steam Injected Gas Turbine (RSTIG), and Regenerative After Fogging Gas Turbine (RAF). Effects of pressure ratio, steam injection ratio and steam injection method on the system performance was theoretically investigated. The results showed that the order of the highest exergy efficiency is RSTIG, RAF, and STIG for low pressure ratios but STIG, RSTIG, and RAF for high pressure ratios. In each arrangement, the combustion chamber has the highest exergy destruction and the compressor has the second one.

• 한국식품영양학회지
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• 제29권2호
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• pp.200-205
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• 2016

The aim of this work was to select suitable fermentation treatments for the efficient bioconversion of cactus (Opuntia humifusa Raf.) bioactive components with an improved radical scavenging activity for use as a nutraceutical. To obtain microorganisms for the microbial conversion of cactus, Leuconostoc mesenteroides ATCC8294, Lactobacillus plantarum KCTC 3099, Lactobacillus plantarum KERI 236 and Monascus pilosus KCCM 60029 (ATCC 22080) were used for fermentation. Fermentation by Lac. plantarum KCTC 3099 was the most effective at scavenging 1,1-diphenyl-2-picrylhydrazyl hydrate (DPPH) and 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals and reducing iron (III). In particular, uronic acid levels showed a remarkable increase in fermentation. The polyphenol and quercetin content of the fermented cactus showed large increases from $108.65{\mu}g/mL$ and $2.71{\mu}g/mL$ to $227.83{\mu}g/mL$ and $9.73{\mu}g/mL$, respectively, showing a maximum level at 36 h of fermentation with Lac. plantarum KCTC 3099. Thus, cactus fermentation with Lac. plantarum is an useful process for the enhancement of antioxidant contents and activity of fresh cactus.

• The Korean Journal of Physiology and Pharmacology
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• 제9권5호
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• pp.299-304
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• 2005

Cardiac hypertrophy contributes an increased risk to major cerebrovascular events. However, the molecular mechanisms underlying cerebrovascular dysfunction during cardiac hypertrophy have not yet been characterized. In the present study, we examined the molecular mechanism of isoproterenol (ISO)-evoked activation of Ras/Raf/MAPK pathways as well as PKA activity in cerebral artery of rabbits, and we also studied whether the activations of these signaling pathways were altered in cerebral artery, during ISO-induced cardiac hypertrophy compared to heart itself. The results show that the mRNA level of c-fos (not c-jun and c-myc) in heart and these genes in cerebral artery were considerably increased during cardiac hypertrophy. These results that the PKA activity and activations of Ras/Raf/ERK cascade as well as c-fos expression in rabbit heart during cardiac hypertrophy were consistent with previous reports. Interestingly, however, we also showed a novel finding that the decreased PKA activity might have differential effects on Ras and Raf expression in cerebral artery during cardiac hypertrophy. In conclusion, there are differences in molecular mechanisms between heart and cerebral artery during cardiac hypertrophy when stimulated with β2 adrenoreceptor (AR), suggesting a possible mechanism underlying cerebrovascular dysfunction during cardiac hypertrophy.

• 대한수의학회지
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• 제40권2호
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• pp.393-401
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• 2000

계난백유래물질(EWD)로 배양한 고양이 말초혈액 단핵구세포(MNC)의 배양상충액에서 다형핵백혈구(PMN)에 대한 유주성인자를 조사하였다. EWD로 배양한 MNC 배양상층액과 human recombinant (hr) interleukin (IL-8)는 고양이 PMN의 유주성을 현저하게 증가시켰다. 이 유주활성물질을 규명하기 위해 EWD 처리 MNC 배양상충액을 gel electro-phoresis(denaturing 조건 18% loading gel 및 nondenaturing 조건 12.5% loading gel)를 실시한 결과, EWD로 배양한 MNC 배양상충액과 hr IL-8는 모두 분자량 6~8kDa에서 band를 나타내었다. Denaturing 조건에서 6~8kDa band의 gel slices에서 용출시킨 용출액에서도 고양이 PMN의 유주활성이 인정되었다. EWD로 배양한 MNC 배양상층액, hr IL-8 및 용출액에 의한 유도된 고양이 PMN의 유주활성은 rabbit anti-feline polyclonal IgG(RAF pIgG)와 hr IL-8에 대한 mAb에 의해 농도의존적으로 억제되었다. 또한 RAF pIgG는 hr IL-8와 결합을 보임으로써 사람의 IL-8와 교차반응을 시사하였다. 이상의 결과로부터 EWD로 배양한 고양이 MNC는 분자량 6~8kDa의 IL-8 양(樣) 유주성인자를 분비하여 PMN의 유주성을 유도하는 것으로 사료되었다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 공동 춘계학술대회
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• pp.27-27
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• 1999

No Abstract, See Full Text

• BMB Reports
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• 제48권6호
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• pp.301-302
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• 2015

Hypoxia is associated with many pathological conditions as well as the normal physiology of metazoans. We identified a lactate-dependent signaling pathway in hypoxia, mediated by the oxygen- and lactate-regulated protein NDRG family member 3 (NDRG3). Oxygen negatively regulates NDRG3 expression at the protein level via the PHD2/VHL system, whereas lactate, produced in excess under prolonged hypoxia, blocks its proteasomal degradation by binding to NDRG3. We also found that the stabilized NDRG3 protein promotes angiogenesis and cell growth under hypoxia by activating the Raf-ERK pathway. Inhibiting cellular lactate production abolishes NDRG3-mediated hypoxia responses. The NDRG3-Raf-ERK axis therefore provides the genetic basis for lactate-induced hypoxia signaling, which can be exploited for the development of therapies targeting hypoxia-induced diseases in addition to advancing our understanding of the normal physiology of hypoxia responses. [BMB Reports 2015; 48(6): 301-302]

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2008년도 추계학술발표회
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• pp.447-448
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• 2008

• Journal of Applied Biological Chemistry
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• 제50권4호
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• pp.254-258
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• 2007

Five flavonoids, isorhamnetin 3-O-${\beta}$-D-galactosyl-4'-O-${\beta}$-D-glucoside (1), isorhamnetin 3,4'-di-O-${\beta}$-D-glucoside (2), isorhamnetin 3-O-${\beta}$-D-(6-O-${\alpha}$-L-rhamnosyl)glucosyl-4'-O-${\beta}$-D-glucoside (3), isorhamnetin 3-O-${\beta}$-D-(6-O-${\alpha}$-L-rhamnosyl)glucoside (4), and isorhamnetin 3-O-${\beta}$-D-(6-O-${\alpha}$-L-rhamnosyl) galactoside (5) were isolated from the stems of Opuntia humifusa (Raf.) Raf. and their structures were identified based on LC-MS and NMR data.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1997년도 한국생물과학협회 학술발표대회
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• pp.301.1-301
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• 1997

No Abstract, See Full Text