• Molecules and Cells
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• v.37 no.9
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• pp.685-690
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• 2014

Osteoclasts are large polykaryons that have the unique capacity to degrade bone and are generated by the differentiation of myeloid lineage progenitors. To identify the genes involved in osteoclast development, we performed microarray analysis, and we found that carboxypeptidase E (CPE), a prohormone processing enzyme, was highly upregulated in osteoclasts compared with their precursors, bone marrow-derived macrophages (BMMs). Here, we demonstrate a novel role for CPE in receptor activator of NF-${\kappa}B$ ligand (RANKL)-induced osteoclast differentiation. The overexpression of CPE in BMMs increases the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinuclear osteoclasts and the expression of c-Fos and nuclear factor of activated T cells c1 (NFATc1), which are key regulators in osteoclastogenesis. Furthermore, employing CPE knockout mice, we show that CPE deficiency attenuates osteoclast formation. Together, our data suggest that CPE might be an important modulator of RANKL-induced osteoclast differentiation.

• Korean Journal of Pharmacognosy
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• v.46 no.4
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• pp.295-302
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• 2015

Cynanchi wilfordii Radix roots have been utilized as traditional medicine for variety of diseases including diabetes mellitus, aging progression and scavenging free radicals, enhancing immunity, reducing high serum cholesterol, and anti-tumor activity. However, the mechanisms underlying this effect remain poorly understood. The principal objective of this study was to determine the effect of cynandione A on osteoclast cells. Thus, we was isolated cynandione A from Cynanchi wilfordii Radix roots and evaluated the effect of cynandione A on receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL)-induced osteoclast differentiation. We found that cynandione A significantly inhibited osteoclast differentiation stimulated-RANKL in RAW 264.7 cells. Cynandione A conspicuously inhibited the mRNA and protein expression of matrix metallopeptidase 9 (MMP-9), tartrate-resistant acid phosphatase (TRAP) in cynandione A treated with RANKL. Taken together, our results demonstrated that Cynanchi Wilfordii Radix may be useful treatment option of bone-related disease such as osteoporosis leads to fracture of bone and rheumatoid arthritis.

• Journal of Information Science Theory and Practice
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• v.5 no.4
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• pp.68-80
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• 2017

The invention of computers is one of the best things that have ever happened to mankind and undergraduate students can benefit immensely from the use of computers. However, observations have showed that in the present Nigerian society, there are a number of issues arising from unethical use of computers. Interactions with some undergraduate students revealed that a majority have fallen into the trap of unethical use of computers at one time or another. This seemingly alarming rate of unethical use of computers therefore calls for concern. A literature search has shown that awareness and perception of computer ethics have not been adequately researched within the Nigerian context. Thus, the main objective of this study was to examine the awareness and perception of computer ethics by undergraduate students in a Nigerian university. Descriptive survey research method was used and the study population was comprised of 12,894 undergraduate students of the University of Ibadan, Nigeria. The multistage random sampling technique was used to select a sample size of 292 and the questionnaire was used to collect data. Findings showed that the level of awareness of respondents on issues associated with computer ethics was high (mean=45.19). A majority of the respondents had a favorable perception of computer ethics and the most prominent factor identified that could hinder adherence to computer ethics as noted by most of the respondents was the poor economic situation of the country. Part of the recommendations was that government at all levels should provide responsible and responsive leadership.

• The Journal of Fisheries Business Administration
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• v.39 no.2
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• pp.25-39
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• 2008

The Korean government is in the establishment process of plan for managing fishing effort by setting up the maximum fishing gear usage per fishery type for the recovery of fishery resources, for the settlement of disputes between fishery sectors over fishing gears, and for the stability of fishing business condition. Especially in the setting up of the maximum fishing gear usage, economic standards as well as biological standards are being considered as a significant factor to promote the sustainable and economically viable development of fisheries. This study is, thus, to analyze the optimal economic fishing gear usage ($E_{MEY}$) as the most economically efficient one for the coastal snow crab gillnet fishery, one of the most controversial sectors in establishing the maximum fishing gear usage. The data of logbooks per trip were used for concentrating on the estimation of $E_{MEY}$ per trip because it was considered there were limitations of data available for analyses. As a finding drawn from the analyses, the optimal economic trap usage ($E_{MEY}$) of coastal snow crab gillnet vessels per trip has to be decreased by about 13%. That is, reducing the trip gillnet usage up to the level of $E_{MEY}$ can lead to the reduction of trip fishing costs, thereby resulting in the increased trip profits.

• International Journal of Oral Biology
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• v.31 no.2
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• pp.67-72
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• 2006

Nitric oxide(NO) is a labile, uncharged, reactive radical that functions as a sensitive mediator of intercellular communication in diverse tissues. It has been reported that NO is produced by osteoblast and these results may suggest that NO is integrally involved in the regulation of osteoclast formation and osteoclast resorption activity by osteoblastic cells. We examined the effect of cytokines on NO release by mouse bone marrow cell. We also examined the effects of cytokines and sodium nitroprusside(SNP) on the formation of osteoclast-like cell from mouse bone marrow cells in culture. Cytokines stimulated NO production of mouse bone marrow cells, and N-nitro-L-arginine methyl ester, a specific inhibitor of NO synthase, suppressed the cytokine-induced NO production. SNP showed dual action in the generation of osteoclasts. The addition of $30{\mu}M$ SNP inhibited the formation of tartrate resistant acid phosphatase(TRAP)(+) multinucleated cell, whereas lower concentration($3{\mu}M$) of SNP enhanced it. Although the precise action of NO remains to be elucidated in detail, the action of NO in osteoclast generation in our studies seems to be associated, at least in part, with bone metabolism and bone pathophysiology.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.899-902
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• 2011

본 연구에서는 MicroTec 시뮬레이터를 이용하여 태양전지의 최적화 효율을 얻기 위한 연구를 하고자 한다. 효율은 태양전지의 성능을 나타내는 가장 중요한 인자로서 태양으로부터 입사된 에너지에 대한 출력에너지의 비로 정의된다. 효율은 입사되는 태양광 스펙트럼이나 세기, 그리고 전지의 온도에 영향을 받기도 하므로 태양전지의 변화효율은 정밀하게 조절된 조건에서 측정되어야 한다. 본 연구에서는 온도(200K-300K)와 Trap(트랩) 에너지(0.1eV~1.0eV) 파라미터의 값을 변화하면서 특성을 분석하였다. 그리고 이동도 모델에 따른 전류-전압 특성을 분석하였다. 분석결과에 따른 곡선 인자(Fill factor를) 비교하여 태양전지의 효율을 최적화 할 수 있는 모델을 제시할 것이다.

• Molecules and Cells
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• v.40 no.5
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• pp.371-377
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• 2017

Despite the importance of the receptor activator of nuclear factor (NF)-kappaB ligand (RANKL)-RANK signaling mechanisms on osteoclast differentiation, little has been studied on how RANK expression is regulated or what regulates its expression during osteoclastogenesis. We show here that insulin signaling increases RANK expression, thus enhancing osteoclast differentiation by RANKL. Insulin stimulation induced RANK gene expression in time- and dose-dependent manners and insulin receptor shRNA completely abolished RANK expression induced by insulin in bone marrow-derived monocyte/macrophage cells (BMMs). Moreover, the addition of insulin in the presence of RANKL promoted RANK expression. The ability of insulin to regulate RANK expression depends on extracellular signal-regulated kinase 1/2 (ERK1/2) since only PD98059, an ERK1/2 inhibitor, specifically inhibited its expression by insulin. However, the RANK expression by RANKL was blocked by all three mitogen-activated protein (MAP) kinases inhibitors. The activation of RANK increased differentiation of BMMs into tartrate-resistant acid phosphatase-positive ($TRAP^+$) osteoclasts as well as the expression of dendritic cell-specific transmembrane protein (DC-STAMP) and d2 isoform of vacuolar ($H^+$) ATPase (v-ATPase) Vo domain (Atp6v0d2), genes critical for osteoclastic cell-cell fusion. Collectively, these results suggest that insulin induces RANK expression via ERK1/2, which contributes to the enhancement of osteoclast differentiation.

• BMB Reports
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• v.52 no.7
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• pp.469-474
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• 2019

Kruppel-like factor 2 (KLF2) has been implicated in the regulation of cell proliferation, differentiation, and survival in a variety of cells. Recently, it has been reported that KLF2 regulates the p65-mediated transactivation of $NF-{\kappa}B$. Although the $NF-{\kappa}B$ pathway plays an important role in the differentiation of osteoclasts and osteoblasts, the role of KLF2 in these bone cells has not yet been fully elucidated. In this study, we demonstrated that KLF2 regulates osteoclast and osteoblast differentiation. The overexpression of KLF2 in osteoclast precursor cells inhibited osteoclast differentiation by downregulating c-Fos, NFATc1, and TRAP expression, while KLF2 overexpression in osteoblasts enhanced osteoblast differentiation and function by upregulating Runx2, ALP, and BSP expression. Conversely, the downregulation of KLF2 with KLF2-specific siRNA increased osteoclast differentiation and inhibited osteoblast differentiation. Moreover, the overexpression of interferon regulatory protein 2-binding protein 2 (IRF2BP2), a regulator of KLF2, suppressed osteoclast differentiation and enhanced osteoblast differentiation and function. These effects were reversed by downregulating KLF2. Collectively, our data provide new insights and evidence to suggest that the IRF2BP2/KLF2 axis mediates osteoclast and osteoblast differentiation, thereby affecting bone homeostasis.

• Journal of Information Display
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• v.12 no.4
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• pp.209-212
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• 2011

The threshold voltage shift (${\Delta}V_{th}$) under positive-voltage bias stress (PBS) of InGaZnO (IGZO) thin-film transistors (TFTs) annealed at different temperatures in air was investigated. The dramatic degradation of the electrical performance was observed at the sample that was annealed at $700^{\circ}C$. The degradation of the saturation mobility (${\mu}_{sat}$) resulted from the diffusion of indium atoms into the interface of the IGZO/gate insulator after crystallization, and the degradation of the subthreshold slope (S-factor) was due to the increase in the interfacial and bulk trap density. In spite of the degradation of the electrical performance of the sample that was annealed at $700^{\circ}C$, it showed a smaller ${\Delta}V_{th}$ under PBS conditions for $10^4$ s than the samples that were annealed at $500^{\circ}C$, which is attributed to the nanocrystal-embedded structure. The sample that was annealed at $600^{\circ}C$ showed the best performance and the smallest ${\Delta}V_{th}$ among the fabricated samples with a ${\mu}_{sat}$ of $9.38cm^2/V$ s, an S-factor of 0.46V/decade, and a ${\Delta}V_{th}$ of 0.009V, which is due to the passivation of the defects by high thermal annealing without structural change.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.1
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• pp.109-114
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• 2011

Atractylodis Rhizoma Alba is commonly used herbal medicine and it has been known that has immuno-regualtory effects and anti-cancer effects. The inhibition of osteoclastogenesis is essential for the prevention and treatment of osteoporosis. The aim of this study was to evaluate the effects of Atractylodis Rhizoma Alba on osteoclast differentiation in vitro and on resorbing activity of osteoclast. Osteoclast formation was evaluated in bone marrow cells (BMC) in the presence or absence of Atractylodis Rhizoma Alba. The expression of c-fos, tartrate-resistant acid phosphatase (TRAP), OSCAR, DC-STAMP, cathepsin K, MafB and NFATc1 mRNA in osteoclast precursor were assessed by RT-PCR. The levels of TNF receptor-associated factor-6 (TRAF-6), c-fos and NFATc1 protein were assessed by Western blot analysis. Also the correlation with MAPKs and NF-${\kappa}B$ pathways were measured by using Western blot analysis. With bone resorption study, I tried to evaluate the inhibitory effects of Atractylodis Rhizoma Alba on mature osteoclast function. Atractylodis Rhizoma Alba inhibited the RANKL induced osteoclastic differentiation from bone marrow macrophage in a dose dependant manner without cellular toxicity. Gene expression of c-fos and NFATc1 was significantly down regulated with Atractylodis Rhizoma Alba treatment. Atractylodis Rhizoma Alba markedly inhibited the RANKL-induced osteoclastogenesis through suppression of nuclear factor kappa b (NF-${\kappa}B$) pathway, down stream pathway of p38, ERK and JNK pathway. Taken together, I concluded that Atractylodis Rhizoma Alba have beneficial effect on osteoporosis by inhibition of osteoclast differentiation and by inhibition of functioning osteoclast. Thus I expect that Atractylodis Rhizoma Alba could be a treatment option for osteoporosis.