• Biomedical Science Letters
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• v.19 no.2
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• pp.168-172
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• 2013

Toll-like receptors (TLRs) play an important role for host defense against invading pathogens. TLR4 has been identified as the receptor for lipopolysaccharide (LPS), which is a cell wall component of gram-negative bacteria. The activation of TLR4 signaling by LPS leads to the activation of NF-${\kappa}B$ and the expression of pro-inflammatory gene products such as cytokines, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2). To evaluate the therapeutic potential of (E)-1-(2-(2-nitrovinyl)phenyl)pyrrolidine (NVPP), previously synthesized in our laboratory, NF-${\kappa}B$ activation and iNOS and COX-2 expression induced by LPS were examined. NVPP inhibited the activation of NF-${\kappa}B$ induced by LPS. NVPP also suppressed the iNOS expression induced by LPS but it did not suppress COX-2 expression induced by LPS. These results suggest that NVPP has the specific mechanism for anti-inflammatory responses.

• Animal cells and systems
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• v.4 no.4
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• pp.381-388
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• 2000

Using a murine T cell hybridoma, activation-induced cell death (AICD) was studied. As an in vitro model system for the AICD, 1 cell hybridoma expressing TCR/CD3 complex was incubated onto the immobilized purified anti-CD3 antibody. The immobilized anti-CD3 antibody induced AICD effectively up to 40%. At 1-100 $\mu$M range of SNP, an exogenous source of nitric oxide (NO), the cell proliferation was not affected, but at 1 mM SNP, cell proliferation was significantly reduced. The AICD of T cell hybridoma was inhibited by exogenous NO at non-cytotoxic concentration, In the cells undergoing AICD, the expressions of caspase-3 and FasL were detected, but not iNOS. Similar result was recognized in the apoptosis induced by dexamethasone, an apoptosis-inducing agent. However, the conversion from the inactive form of caspase-3 (32 kDa) to the active form (17 kDa) was significantly reduced in the cells in AICD induced by anti-CD3 antibody, With the result of increased PARP cleavage in the cells, we propose that another PARP cleavage pathway not involving caspase-3 may function in the anti-CD3 antibody induced AICD in the T cell hybridoma.

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.134.2-135
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• 2001

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.931-934
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• 2009

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.241.2-241
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• 2000

No Abstract, See Full Text

• Journal of Integrative Natural Science
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• v.12 no.2
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• pp.29-34
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• 2019

In dental resin cement studies, viscosity is also an important factor in the adhesion of tooth defects and implants. This study used BisGMA and HPMA as the main ingredients, triethylene glycol dimethacrylate (TEGDMA) as a diluent, and benzoyl peroxide (BPO) as a photoinitiator. The physical properties of graphene oxide used as an additive for functionality were evaluated, and its use as a dental resin cement material was investigated.The rupture strength has the tendency to increase along with the increase of the ratio of graphene oxide that was added, which seemed to reflect the effect of the high strength property of graphene oxide. The flexural strength also has the tendency to increase when about 0.5% of graphene oxide was added the same as the increase of rupture strength.When graphene oxide was added, according to viscosity use, the utilization as high-quality dental resin cements will increase.

• Nuclear Engineering and Technology
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• v.51 no.4
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• pp.996-1007
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• 2019

We investigated the influence of the aspect ratio (H/R) of the oxide layer on the reactor vessel heating in three-layer configuration. Based on the analogy between heat and mass transfers, we performed mass transfer experiments to achieve high Rayleigh numbers ranging from $6.70{\times}10^{10}$ to $7.84{\times}10^{12}$. Two-dimensional (2-D) semi-circular apparatuses having the internal heat source were used whose surfaces of top, bottom and side simulate the interfaces of the oxide layer with the light metal layer, the heavy metal layer, and the reactor vessel, respectively. Multi-cell flow pattern was identified when the H/R was reduced to 0.47 or less, which promoted the downward heat transfer from the oxide layer and possibly mitigated the focusing effect at the upper metallic layer. The top boundary condition greatly affected the natural convection of the oxide layer due to the presence of secondary flows underneath the cold light metal layer.

• The Journal of the Korea Contents Association
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• v.9 no.7
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• pp.211-217
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• 2009

In order to find out the radioprotective effect of algin-oligosaccharide, this study, with a mouse of which whole body irradiated by 3 Gy radiation once, measured nitric oxide. In nitric oxide test for observing the reaction of cell inflammation, nitric oxide showed decreased in the irradiation control group, while 3 day's treatment group with algin-oligosaccharide before or after irradiation indicated higher than the irradiation control group, especially showed big difference in 3 day's treatment group before irradiation (P<0.001). Consequently, this study inquired into the fact that algin-oligosaccharide with superior antioxidant activity performed radiation protection by increasing promotion of nitric oxide generation and confirmed that natural product with less chemical toxicity was able to be applied as radioprotector.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.231-236
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• 2008

The current work was designed to assess novel pharmacological activities of 4-hydroxybenzaldehyde (HD), a major phenolic constituent of various natural products of plant origin, such as Gastrodia elata Blume. HD exhibited a significant inhibition in the chick chorioallantoic membrane (CAM) angiogenesis. HD also displayed an inhibitory effect in acetic acid-induced permeability in mice. Anti-nociceptive activity of HD was convinced using the acetic acid-induced writhing test in mice. HD was able to suppress production of nitric oxide (NO) and induction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in the lipopolysaccharide (LPS)-activated RAW264.7 macrophages. HD also diminished the reactive oxygen species (ROS) level elevated in the LPS-activated macrophages. In brief, HD exhibits anti-angiogenic, anti-inflammatory and anti-nociceptive activities possibly via down-regulating iNOS and/or COX-2, which may be partly responsible for pharmacological efficacies of various natural products.

• Molecules and Cells
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• v.26 no.1
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• pp.48-52
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• 2008

We here demonstrate an anti-inflammatory action of raloxifene, a selective estrogen receptor modulator, in lipopolysaccharide (LPS)-induced murine macrophage RAW264.7 cells. Treatment with raloxifene at micromolar concentrations suppressed the production of nitric oxide (NO) by down-regulating expression of the inducible nitric oxide synthase (iNOS) gene in LPS-activated cells. The decreased expression of iNOS and subsequent reduction of NO were due to inhibition of nuclear translocation of transcription factor NF-${\kappa}B$. These effects were significantly inhibited by exposure to the phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor, LY294002, or by expression of a dominant negative mutant of PI 3-kinase. In addition, pretreatment with raloxifene reduced LPS-induced Akt phosphorylation as well as NF-${\kappa}B$ DNA binding activity and NF-${\kappa}B$-dependent reporter gene activity. Thus our findings indicate that raloxifene exerts its anti-inflammatory action in LPS-stimulated macrophages by blocking the PI 3-kinase-Akt-NF-${\kappa}B$ signaling cascade, and eventually reduces expression of pro-inflammatory genes such as iNOS.