• 무역학회지
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• 제45권5호
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• pp.91-116
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• 2020

The construction industry can be described as one of the most volatile industry depending on the situation. As such, a contractor, who is usually positioned to take all kinds of risk, may frequently require to form a strategic partnership for better execution of a project. In this study, we are going to review act or behavior that may happen among such partnership. For such review, a survey targeted at domestic construction companies has been conducted on their thoughts as regards opportunism, risk perception, and the contractual governance between partners. The analysis result of structural equation and regression has indicated that there exists a positive effect on the opportunistic behavior from the risk perception, a moderating effect on contractual governance between the performance risk and opportunism, whereas no such moderating effect on the same between relational risk and the opportunism. The output of this study may assist various domestic individuals who wish to participate large scaled overseas projects.

• 한국식품영양과학회지
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• 제39권3호
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• pp.356-362
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• 2010

동결건조된 솔잎(Pinus densiflora needles)으로부터 냉수(PD-CW), 열수(PD-HW)와 메탄올추출물(PD-M)을 분획하여 in vitro에서 Peyer's patch를 경유한 장관면역 활성을 측정한 결과, PD-M 획분에서 유력한 골수세포 증식활성을 나타내었다. 메탄올 추출방법을 확립하기 위하여 MeOH 추출물을 균질화, 교반 또는 환류 등의 방법으로 조제하였을 때, 환류방법으로 조제된 MeOH 추출물에서 유의적(p<0.05)으로 가장 높은 장관면역 활성을 in vitro에서 확인할 수 있었다. 솔잎으로부터 분획된 PD-M을 마우스에 경구 투여하고 Peyer's patch를 분리하여 ex vivo에서의 장관면역 활성도 관찰하였다. 다양한 농도로 1주일 동안 PD-M을 경구투여 한 결과, 1.0 g/kg of BW/day의 용량으로 경구투여 한 C3H/He 마우스의 Peyer's patch로부터 얻은 세포배양 상등액에서 saline 대조군보다 2.5배의 높은 장관면역 활성을 보여주었다(p<0.05). 또한 다양한 농도로 경구투여 된 Peyer's patch 세포의 배양액을 이용하여 측정한 IL-6 생산능은 1.0 g/kg of BW/day의 용량에서 1.13배로 증가하였으나 GM-CSF는 처리 용량에 따라 유의적인 값을 보이지는 않았다. 이러한 결과는 PD-M의 경구투여가 Peyer's patch 세포로부터 GM-CSF와 IL-6 등의 조혈세포 증식인자의 분비를 촉진함을 나타내는 것이며, 이러한 cytokine들이 골수세포 증식의 조절인자로서 작용함을 보여주는 것으로 생각한다.

• 대한한의학회지
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• 제24권2호
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• pp.166-178
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• 2003

Objectives : Nitric oxide (NO) plays an important role in normal and pathophysiological cells as a messenger molecule, neurotransmitter, microbiological agent, or dilator of blood vessels and arteriosclerosis, respectively. This study was undertaken to understand the mechanism of NO production and effect of Hyeolbuchukeo-tang (Xiefuzhuyu-tang) on NO production in cultured vascular smooth muscle cell (VSMC). Methods and Results : VSMC was isolated from aorta and cultured. Cultured primary cells were identified as VSMC with anti--smooth muscle actin antibody. A large amount of NO was produced in cultured VSMC treated with $IFN-{\gamma}$ plus TNF in a time- and dose-dependent manner. $TNF-{\alpha}$ was a more efficient stimulator than $IFN-{\gamma}$ in NO production of cultured VSMC. iNOS protein wasdetected within 3 hrs and it increased up to 12 hrs in a time-dependent manner. However, accumulated NO in cytokine-treated VSMC was not detected within 3 hrs. NO production in cytokine-treated VSMC showed the dose- and time-dependent manner, and increased up to 48 hrs. The activated VSMC produced a large amount of NO (about 60 uM). Hyeolbuchukeo-tang (Xiefuzhuyu-tang) alone did not induceNO production, but it potentiated the effect of $TNF-{\alpha}$ on NO production and increased NO production by about 20%. Hyeolbuchukeo-tang (Xiefuzhuyu-tang) did not affect the transcriptional activity of iNOS gene, but increased the accumulation of iNOS. These results indicate that Hyeolbuchukeo-tang (Xiefuzhuyu-tang) could modulate the translational level of iNOS. PKC did not modulate NO production, but calcium ionophore A23187 decreased NO production. However, Hyeolbuchukeo-tang (Xiefuzhuyu-tang) elevated the decreased NO production in A23187-treated VSMC by modulating the stability of iNOS transcripts. Half-life of the synthesized transcripts appeared to have about 6 hrs. PDTC, an $NF-{\kappa}B$ inhibitor, blocked the accumulation of iNOS mRNA, indicating that $NF-{\kappa}B$ served as an important modulator in the transcriptional regulation of iNOS. As Hyeolbuchukeo-tang (Xiefuzhuyu-tang) potentiated the effect of the $TNF-{\alpha}$ on NO production but had no additional effect on PDTC-modulated NO production, it is suggested that Hyeolbuchukeo-tang (Xiefuzhuyu-tang) enhances the $TNF-{\alpha}-mediated$ NO production of VSMC by modulating the iNOS activity and the stability of iNOS transcripts in activated VSMC having the elevated intracellular calcium ion. Conclusions : This study suggests that Hyeolbuchukeo-tang (Xiefuzhuyu-tang) has a potential capacity for preventing and treating diseases of the circulation system, including arteriosclerosis.

• IMMUNE NETWORK
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• 제9권5호
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• pp.192-202
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• 2009

Background: Little information is available the role of Nitric Oxide (NO) in host defenses during human tuberculosis (TB) infection. We investigated the modulating factor(s) affecting NO synthase (iNOS) induction in human macrophages. Methods: Both iNOS mRNA and protein that regulate the growth of mycobacteria were determined using reverase transcriptase-polymerase chain reaction and western blot analysis. The upstream signaling pathways were further investigated using iNOS specific inhibitors. Results: Here we show that combined treatment with 1,25-dihydroxyvitamin D3 (1,25-D3) and Interferon (IFN)-${\gamma}$ synergistically enhanced NO synthesis and iNOS expression induced by Mycobacterium tuberculosis (MTB) or by its purified protein derivatives in human monocyte-derived macrophages. Both the nuclear factor-${\kappa}B$ and MEK1-ERK1/2 pathways were indispensable in the induction of iNOS expression, as shown in toll like receptor 2 stimulation. Further, the combined treatment with 1,25-D3 and IFN-${\gamma}$ was more potent than either agent alone in the inhibition of intracellular MTB growth. Notably, this enhanced effect was not explained by increased expression of cathelicidin, a known antimycobacterial effector of 1,25-D3. Conclusion: These data support a key role of NO in host defenses against TB and identify novel modulating factors for iNOS induction in human macrophages.

• 한국가금학회지
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• 제39권1호
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• pp.33-37
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• 2012

One of the biggest challenges for the animal feed industry in the coming years will be to meet the growing demand in animal protein in light of increased cost of feed ingredient as well as tougher restrictions on the use of antimicrobial growth promoters imposed by consumers and governments. A key focus area will be to maximise feed efficiency and minimise nutrient waste. It has been widely acknowledged that the composition of the intestinal microflora is closely related to intestinal health and performance of animals. Advanced microbial techniques have shown a close relationship between bacterial communities and their ability to modulate nutrient absorption and processing. In addition it has been recognised that modulating the immune response has significant impact on overall health as well as overall nutrient demand. Molecular techniques are a useful tool to gain an understanding of the impact of dietary interventions including the use of functional feed additives on specific changes in microbial communities or the immune system. Most these techniques however focus on the evaluation of large changes in bacterial compositions and often underestimate or neglect to recognise small changes in microbial diversity or behaviour changes without any measurable immune response. The key to understanding the relationship between specific nutritional intervention and the impact on health and performance lies in a deeper understanding of the impact of these nutrients on the expression of specific genes or specific metabolic pathways. The development of molecular tools as a result of developments in the field of Nutrigenomics has enabled researchers to study the effects of specific nutrients on the whole genome or in other words, the effect of thousands of genes simultaneously, and has opened a completely different avenue for nutritional research.

• 대한약침학회지
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• 제19권2호
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• pp.129-136
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• 2016

Objectives: The crude extracts of Scutellaria barbata D. Don (SB) have traditionally demonstrated inhibitory effects on numerous human cancers both in vitro and in vivo. Gastric cancer is one of the most common types of cancer on world. The authors investigated the effects of an ethanol extract of Scutellaria barbata D. Don (ESB) on the growth and survival of MKN-45 cells (a human gastric adenocarcinoma cell line). Methods: The MKN-45 cells were treated with different concentrations of ESB, and cell death was examined using an MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. Analyses of sub-G1 peaks, caspase-3 and -9 activities, and mitochondrial membrane depolarizations were conducted to determine the anti-cancer effects of SB on MKN-45 cells. Also, intracellular reactive oxygen species (ROS) generation was investigated. Results: ESB inhibited the growth of MKN-45 cells, caused cell cycle arrest, and increased the sub-G1 population. In addition, ESB markedly increased mitochondrial membrane depolarization and the activities of caspase-3 and -9. ESB exerted anti-proliferative effects on MKN-45 cells by modulating the mitogen-activated protein kinase (MAPK) signaling pathway and by increasing the generation of ROS. Furthermore, combinations of anti-cancer drugs plus ESB suppressed cell growth more than treatments with an agent or ESB, and this was especially true for cisplatin, etoposide, and doxorubicin. Conclusion: ESB has a dose-dependent cytotoxic effect on MKN-45 cells and this is closely associated with the induction of apoptosis. ESB-induced apoptosis is mediated by mitochondria-, caspase- and MAPK dependent pathways. In addition, ESB enhances ROS generation and increases the chemosensitivity of MKN-45 cells. These results suggest that treatment with ESB can inhibit the proliferation and promote the apoptosis of human gastric adenocarcinoma cells by modulating the caspase-, MAPK- and ROS-dependent pathway.

• The Korean Journal of Physiology and Pharmacology
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• 제16권1호
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• pp.17-24
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• 2012

The hypothalamus-pituitary-adrenocortex (HPA) axis is the central mediator of the stress response. The supramammillary (SuM) region is relatively unique among the hypothalamic structures in that it sends a large, direct projection to the hippocampal formation. It has been shown that mild stress could activate the SuM cells that project to the hippocampus. However, the role of these cell populations in modulating the stress response is not known. The present study examined the effect of stress on different populations of SuM cells that project to the hippocampus by injecting the fluorescent retrograde tracer, fluorogold (FG), into the hippocampus and utilizing the immunohistochemistry of choline acetyltransferase (ChAT), corticotrophin releasing factor (CRF), serotonin (5-HT), glutamate decarboxylase (GAD), tyrosine hydroxylase (TH) and NADPH-d reactivity. Immobilization (IMO) stress (2 hr) produced an increase in the expression of ChAT- immunoreactivity, and tended to increase in CRF, 5-HT, GAD, TH-immunoreactivity and nitric oxide (NO)-reactivity in the SuM cells. Fifty-three percent of 5-HT, 31% of ChAT and 56% of CRF cells were double stained with retrograde cells from the hippocampus. By contrast, a few retrogradely labeled cells projecting to the hippocampus were immunoreactive for dopamine, ${\gamma}$-aminobutyric acid (GABA) and NO. These results suggest that the SuM region contains distinct cell populations that differentially respond to stress. In addition, the findings suggest that serotonergic, cholinergic and corticotropin releasing cells projecting to the hippocampus within the SuM nucleus may play an important role in modulating stress-related behaviors.

• Nutrition Research and Practice
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• 제11권5호
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• pp.430-434
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• 2017

BACKGROUND/OBJECTIVE: Chronic hyperglycemia induces oxidative stress via accumulation of reactive oxygen species (ROS) and contributes to diabetic complications. Hyperglycemia induces mitochondrial superoxide anion production through the increased activity of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. This study aimed to determine whether fisetin and luteolin treatments suppress the oxidative stress by modulating the expression of sirtuins (SIRTs) and forkhead box O3a (FOXO3a) under hyperglycemic conditions in human monocytes. MATERIALS/METHODS: Human monocytic cells (THP-1) were cultured under osmotic control (14.5 mmol/L mannitol), normoglycemic (NG, 5.5 mmol/L glucose), or hyperglycemic (HG, 20 mmol/L glucose) conditions, in the absence or presence of fisetin and luteolin for 48 h. To determine the effect of fisetin and luteolin treatments on high glucose-induced oxidative stress, western blotting and intracellular staining were performed. RESULTS: Hyperglycemic conditions increased the ROS production, as compared to normoglycemic condition. However, fisetin and luteolin treatments inhibited ROS production under hyperglycemia. To obtain further insight into ROS production in hyperglycemic conditions, evaluation of p47phox expression revealed that fisetin and luteolin treatments inhibited p47phox expression under hyperglycemic conditions. Conversely, the expression levels of SIRT1, SIRT3, SIRT6, and FOXO3a were decreased under high glucose conditions compared to normal glucose conditions, but exposure to fisetin and luteolin induced the expression of SIRT1, SIRT3, SIRT6, and FOXO3a. The above findings suggest that fisetin and luteolin inhibited high glucose-induced ROS production in monocytes through the activation of SIRTs and FOXO3a. CONCLUSIONS: The results of our study supports current researches that state fisetin and luteolin as potential agents for the development of novel strategies for diabetes.

• BMB Reports
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• 제51권10호
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• pp.508-513
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• 2018

Fibronectin fragments found in the synovial fluid of patients with osteoarthritis (OA) induce the catabolic responses in cartilage. Nuclear high-mobility group protein Box 1 (HMGB1), a damage-associated molecular pattern, is responsible for the regulation of signaling pathways related to cell death and survival in response to various stimuli. In this study, we investigated whether changes induced by 29-kDa amino-terminal fibronectin fragment (29-kDa FN-f) in HMGB1 expression influences the pathogenesis of OA via an HMGB1-modulated autophagy signaling pathway. Human articular chondrocytes were enzymatically isolated from articular cartilage. The level of mRNA was measured by quantitative real-time PCR. The expression of proteins was examined by western blot analysis, immnunofluorescence assay, and enzyme-linked immunosorbent assay. Interaction of proteins was evaluated by immunoprecipitation. The HMGB1 level was significantly lower in human OA cartilage than in normal cartilage. Although 29-kDa FN-f significantly reduced the HMGB1 expression at the mRNA and protein levels 6 h after treatment, the cytoplasmic level of HMGB1 was increased in chondrocytes treated with 29-kDa FN-f, which significantly inhibited the interaction of HMGB1 with Beclin-1, increased the interaction of Bcl-2 with Beclin-1, and decreased the levels of Beclin-1 and phosphorylated Bcl-2. In addition, the level of microtubule-associated protein 1 light chain 3-II, an autophagy marker, was down-regulated in chondrocytes treated with 29-kDa FN-f, whereas the effect was antagonized by mTOR knockdown. Furthermore, prolonged treatment with 29-kDa FN-f significantly increased the release of HMGB1 into the culture medium. These results demonstrated that 29-kDa FN-f inhibits chondrocyte autophagy by modulating the HMGB1 signaling pathway.

• Archives of Pharmacal Research
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• 제25권5호
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• pp.561-571
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• 2002

The action mechanisms of several chemopreventive agents derived from herbal medicine and edible plants have become attractive issues in cancer research. Tea is the most widely consumed beverage worldwide. Recently, the cancer chemopreventive actions of tea have been intensively investigated. It have been demonstrated that the active principles of tea were attributed to their tea polyphenols. Recently, tremendous progress has been made in elucidating the molecular mechanisms of cancer chemoprevention by tea and tea polyphenols. The suppression of various tumor biomarkers including growth factor receptor tyrosine kinases, cytokine receptor kinases, P13K, phosphatases, ras, raf, MAPK cascades, NㆍFB, IㆍB kinase, PKA, PKB, PKC, c-jun, c-fos, c-myc, cdks, cyclins, and related transducing proteins by tea polyphenols has been studied in our laboratory and others. The IㆍB kinase (IKK) activity in LPS-activated murine macrophages (RAW 264.7 cells) was found to be inhibited by various tea polyphenols including (-) epigallocatechin-3-gallate (EGCG), theaflavin (TF-1), theaflavin-3-gal-late (TF-2) and theaflavin-3,3'-digallate (TF-3). TF-3 inhibited IKK activity in activated macrophages more strongly than did the other tea polyphenols. TF-3 inhibited both IKK1 and IKK2 activity and prevented the degradation of IㆍBㆍand IㆍBㆍin activated macrophage cells. The results suggested that the inhibition of IKK activity by TF-3 and other tea polyphenols could occur by a direct effect on IKKs or on upstream events in the signal transduction pathway. TF-3 and other tea polyphenols blocked phosphorylation of IB from the cytosolic fraction, inhibited NFB activity and inhibited increases in inducible nitric oxide synthase levels in activated macrophage. TF-3 and other tea polyphenols also inhibited strongly the activities of xanthine oxidase, cyclooxygenase, EGF-receptor tyrosine kinase and protein kinase C. These results suggest that TF-3 and other tea polyphenols may exert their cancer chemoprevention through suppressing tumor promotion and inflammation by blocking signal transduction. The mechanisms of this inhibition may be due to the blockade of the mitogenic and differentiating signals through modulating EGFR function, MAPK cascades, NFkB activation as wll as c-myc, c-jun and c-fos expression.