• Environmental Analysis Health and Toxicology
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• v.25 no.2
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• pp.111-120
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• 2010

DEPs (diesel exhaust particles) like any other particles can be also inhaled into lung to participate in a damaging reaction to the organ. Possible damages might be apoptosis and inflammatory responses to the cells in respiratory track. The aim of this study was cytotoxicity evaluation of DEPs from five in-use diesel vehicles using a murine macrophage cell (RAW 254.7). We found that most DEPs have a considerable cytotoxicity compared to the control and SRM 2975. When measured by MTT assay and extents of apoptosis, DEPs of two highmileage vehicles had higher toxicity than those of the other three low-mileage vehicles tested. Although mRNA expression level of TNF-${\alpha$ somewhat explains the trend of cytotoxicity and apoptosis, that of IL-1$\beta$ did not. Correlation studies among the extents of MTT assay, apoptosis, and TNF-$\alpha$ expression showed that the extents between apoptosis and TNF-$\alpha$ expression was most highly correlated (r=0.96). These results suggest that cytotoxicity of various DEPs could be compared easily by measuring the extent of apoptosis or TNF-$\alpha$ expression by DEPs.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.2
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• pp.107-112
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• 2012

Although various derivatives of caffeic acid have been reported to possess a wide variety of biological activities such as neuronal protection against excitotoxicity and anti-inflammatory property, the biological activity of 3,4,5-trihydroxycinnamic acid (THC), a derivative of hydroxycinnamic acids, has not been clearly examined. The objective of the present study is to evaluate the anti-inflammatory effects of THC on lipopolysaccharide (LPS)-stimulated BV2 microglial cells. THC significantly suppressed LPS-induced excessive production of nitric oxide (NO) and expression of iNOS, which is responsible for the production of iNOS. THC also suppressed LPS-induced overproduction of pro-inflammatory cytokines such as IL-$1{\beta}$and TNF-${\alpha}$ in BV2 microgilal cells. Furthermore, THC significantly suppressed LPS-induced degradation of $I{\kappa}B$, which retains NF-${\kappa}B$ in the cytoplasm. Therefore, THC attenuated nuclear translocation of NF-${\kappa}B$, a major pro-inflammatory transcription factor. Taken together, the present study for the first time demonstrates that THC exhibits antiinflammatory activity through the suppression of NF-${\kappa}B$ transcriptional activation in LPS-stimulated BV2 microglial cells.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.6
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• pp.491-497
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• 2015

Traumatic brain injury (TBI) is a major cause of mortality and long-term disability, which can decrease quality of life. In spite of numerous studies suggesting that Epigallocatechin-3- gallate (EGCG) has been used as a therapeutic agent for a broad range of disorders, the effect of EGCG on TBI remains unknown. In this study, a weight drop model was established to evaluate the therapeutic potential of EGCG on TBI. Rats were administered with 100 mg/kg EGCG or PBS intraperitoneally. At different times following trauma, rats were sacrificed for analysis. It was found that EGCG (100 mg/kg, i.p.) treatment significantly reduced brain water content and vascular permeability at 12, 24, 48, 72 hour after TBI. Real-time PCR results revealed that EGCG inhibited TBI-induced IL-$1{\beta}$ and TNF-${\alpha}$ mRNA expression. Importantly, CD68 mRNA expression decreasing in the brain suggested that EGCG inhibited microglia activation. Western blotting and immunohistochemistry results showed that administering of EGCG significantly inhibited the levels of aquaporin-4 (AQP4) and glial fibrillary acidic protein (GFAP) expression. TBI-induced oxidative stress was remarkably impaired by EGCG treatment, which elevated the activities of SOD and GSH-PX. Conversely, EGCG significantly reduced the contents of MDA after TBI. In addition, EGCG decreased TBI-induced NADPH oxidase activation through inhibition of $p47^{phox}$ translocation from cytoplasm to plasma membrane. These data demonstrate that EGCG treatment may be an effective therapeutic strategy for TBI and the underlying mechanism involves inhibition of oxidative stress.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4217-4224
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• 2014

Cholangiocarcinoma (CCA), a slow growing but highly metastatic tumor, is highly prevalent in Northeast Thailand. Specific tests that predict prognosis of CCA remain elusive. The present study was designed to investigate whether peripheral blood leukocyte (PBL) transcriptional profiles might be of use as a prognostic test in CCA patients. Gene expression profiles of PBLs from 9 CCA and 8 healthy subjects were conducted using the Affymetrix HG_U133 Plus 2.0 GeneChip. We indentified informative PBLs gene expression profiles that could reliably distinguish CCA patients from healthy subjects. Of these CCA specific genes, 117 genes were up regulated and 60 were down regulated. The molecular and cellular functions predicted for these CCA specific genes according to the Gene Ontology database indicated differential PBL expression of host immune response and tumor progression genes (EREG, TGF ${\beta}1$, CXCL2, CXCL3, IL-8, and VEGFA). The expression levels of 9 differentially expressed genes were verified in 36 CCA vs 20 healthy subjects. A set of three tumor invasion related genes (PLAU, CTSL and SERPINB2) computed as "prognostic index" was found to be an independent and statistically significant predictor for CCA patient survival. The present study shows that CCA PBLs may serve as disease predictive clinically accessible surrogates for indentifying expressed genes reflective of CCA disease severity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.314-314
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• 2010

The SiC-$ZrB_2$ composites were fabricated by combining 40vol.% of Zirconium Diboride(hereafter, $ZrB_2$) powders with Silicon Carbide(hereafter, SiC) matrix. TheSiC+40vol.%$ZrB_2$ composites were manufactured through Spark Plasma Sintering(hereafter, SPS) under argon atmosphere, uniaxial pressure of 50MPa, heating rate of $100^{\circ}C$/min, sintering temperature of $1,500^{\circ}C$ and holding time of 5min. But one on/off pulse sequence(one pulse time: 2.78ms) is 10:9(hereafter, SZ10), and the other is 48:8(hereafter, SZ48). The physical and mechanical properties of the SZ12 and SZ48 were examined. Reactions between $\beta$-SiC and $ZrB_2$ were not observed via X-Ray Diffraction(hereafter, XRD) analysis. The apparent porosity of the SZ10 and SZ48 composites were 9.7455 and 12.2766%, respectively. The SZ10 composite, 593.87MPa, had higher flexural strength than the SZ48 composite, 324.78MPa, at room temperature. The electrical properties of the SiC-$ZrB_2$ composites had Positive Temperature Coefficient Resistance(hereafter, PTCR).

• Tuberculosis and Respiratory Diseases
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• v.49 no.1
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• pp.18-29
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• 2000

호흡기 바이러스 감염은 모든 연령층의 천식에 상당한 영향을 미치는 데 영아에서 RSV는 천명을 야기하고 대부분 일시적이나 재발성 일수도 있다. 어릴 때 바이러스 감염은 면역체계 형성에 영향를 미쳐 알러지와 천식의 위험을 완하할 수있다고 한다. 또한 소아와 성인 천식에서 RV같은 감기 바이러스는 천식의 급성 증상을 유발한다. 호흡기 바이러스 감염에 대한 면역반응이, 기관지로 부터 바이러스 제거 기능외에 기도수축과 호흡기 증상에 관여한다고 한다. 이러한 변화가 일어나는 기전은 호흡기 바이러스가 proinflammatory 사이토카인과 매개체 생성을 유도하는 능력과 연관성이 있는 것 같고 이들이 상하기도 호흡기 증상 및 기도반응 변화에 관여하는 것으로 생각된다. 호흡기 바이러스 감염에 대한 면역반응을 요약하면 바이러스 감염으로 상피세포, 내피세포, 과립백혈구가 활성화되며, 상피세포는 사이토카인, 키모카인, 매개체들을 분비하여 항 면역 반응를 주도하다. 이와 같은 상피세포와 다른 기관지 세포들의 조기 활성화로 내피 세포에 유착분자 표현을 증가시켜 백혈구 동원 증가 및 혈관 투과성을 증가시켜 부종과 분비물을 증가시킨다. 바이러스 또는 바이러스 유발 사이토카인에 의해 활성화된 과립 백혈구, 대식세포, T세포들도 기도염증 증가, 기도폐쇄를 야기하고 기도반응을 증가시킨다. 세포독성 임파구에 의한 바이러스 감염세포의 분해, TGF-$\beta$ IL-10 같은 사이토카인에 의해 부분적으로 염증억제, 기도 remoldeling에 의한 기도구조의 재생등이 바이러스 감염후 기관지 기능의 지속적 변화를 결정한다. 끝으로 천식환자에서 RV 감염의 병인에 관한 기본적 문제는 RV감염이 정상인에서는 경한 증상을 나타내는 데 천식환자에서는 왜 심한 임상증상을 나타내는지 아직 완전히 밝혀지지 않았다. 항 바이러스에 대한 면역반응이 천식환자에서 손상되었는지 또는 천식환자에서 RV감염에 의한 중증의 임상증상은 어떤 다른 세포가 관여하는지? 이들에 대한 답은 기도염증이 천식에서 어떻게 조절되는지 또한 바이러스 감염에 의한 악화된 증상을 어떻게 치료할 것인가에 대한 방향을 제시해줄 것이다.

• Biomolecules & Therapeutics
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• v.24 no.6
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• pp.638-649
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• 2016

In the previous study, the rhizome mixture of Anemarrhena asphodeloides and Coptis chinensis (DW2007), improved TNBS-, oxazolone-, or DSS-induced colitis in mice by regulating macrophage activation. Therefore, to understand the effect of DW2007 on the T cell differentiation involved in the adaptive immunity, we measured its effect on both Th17 and Treg cell differentiation in splenocytes, in the lamina propria of mice with DSS-induced colitis (DIC), and in the spleens of mice with collagen-induced arthritis (CIA). Results showed that DW2007 potently inhibited the differentiation of splenocytes into Th17 cells, but increased Treg cell differentiation in vitro. In the colon of wild type and $TLR4^{-/-}$ mice with DIC, DW2007 potently suppressed DSS-induced colon shortening and myeloperoxidase activity. DW2007 also suppressed collagen-induced paw thickening, clinical index, and myeloperoxidase activity in CIA mice. Overall, DW2007 potently suppressed Th17 cell differentiation in mice with CIA and DIC, but increased Treg cell differentiation. Moreover, DW2007 strongly inhibited the expression of TNF-${\alpha}$ and IL-$1{\beta}$, as well as the activation of NF-${\kappa}B$. Based on these findings, DW2007 may ameliorate inflammatory diseases by regulating the innate immunity via the inhibition of macrophage activation and the adaptive immunity via the correction of disturbed Th17/Treg cells.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.8
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• pp.153-165
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• 1995

The design procedure of a GaAs/AlGaAs semiconductor matrix optical switch is presented for a simplified tree architecture in the viewpoint of optical loss. A low loss, 0.537 dB/cm, pin type substrate is designed by considering the loss due to imputity doping at 1.3 $\mu$m wavelength. The operating voltage and the device length of a reversed ${\Delta}{\beta}$ electro-optic directional coupler(EODC) swith which is a cross-point device of the 4${\times}$4 matrix optical switch and the bending loss of rib waveguide are caculated as functions of waveguide parameters and bending parameters. There is an optimum bending radius for some waveguide parameters. It is recommened that higher optical confinement conditions such as wide waveguide width and higher rib-height should be chosen for structural parameters of a low loss and a process insensitive 4${\times}$4 matris optical switch. A 4${\times}$4 optical matrix switch which has a 3 dB loss and a 12 volt operating voltage is designed.

• Journal of Periodontal and Implant Science
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• v.47 no.6
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• pp.381-387
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• 2017

Purpose: The aim of this study was to evaluate volumetric and histologic changes in edentulous alveolar ridge areas after ridge preservation using basic fibroblast growth factor-2 (bFGF-2) in combination with collagenated biphasic calcium phosphate (BCP). Methods: The experiments were performed in 6 adult male beagle dogs. The following 3 groups were created: 1) ridge preservation with bFGF-2 and collagenated BCP (experimental group), 2) ridge preservation with collagenated BCP (positive control group), and 3) a negative control group in which no ridge preservation procedure was performed. Volumetric change analysis was performed using an optical scanner and casts. Histological observations were made using light microscopy. Results: After the initial swelling subsided, the magnitude of the volumetric change in the experimental group and positive control group was smaller than in the negative control group. In the experimental group, a distinct trend was observed for the resorption of residual bone and collagen fibers at 4 weeks and for more mature bone and faster healing at 12 weeks. Conclusions: Based on the findings of the present study, bFGF-2 may be considered for use as a therapeutic molecule in ridge preservation procedures.

• BMB Reports
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• v.41 no.6
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• pp.415-434
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• 2008

Phosphoinositide-specific phospholipase C is an effector molecule in the signal transduction process. It generates two second messengers, inositol-1,4,5-trisphosphate and diacylglycerol from phosphatidylinositol 4,5-bisphosphate. Currently, thirteen mammal PLC isozymes have been identified, and they are divided into six groups: PLC-$\beta$, -$\gamma$, -$\delta$, -$\varepsilon$, -$\zeta$ and -$\eta$. Sequence analysis studies demonstrated that each isozyme has more than one alternative splicing variant. PLC isozymes contain the X and Y domains that are responsible for catalytic activity. Several other domains including the PH domain, the C2 domain and EF hand motifs are involved in various biological functions of PLC isozymes as signaling proteins. The distribution of PLC isozymes is tissue and organ specific. Recent studies on isolated cells and knockout mice depleted of PLC isozymes have revealed their distinct phenotypes. Given the specificity in distribution and cellular localization, it is clear that each PLC isozyme bears a unique function in the modulation of physiological responses. In this review, we discuss the structural organization, enzymatic properties and molecular diversity of PLC splicing variants and study functional and physiological roles of each isozyme.