• Title/Summary/Keyword: trap factor

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Inhibitory Effect of Standardized Curcuma xanthorrhiza Supercritical Extract on LPS-Induced Periodontitis in Rats

  • Kook, Kyo Eun;Kim, Changhee;Kang, Wonku;Hwang, Jae-Kwan
    • Journal of Microbiology and Biotechnology
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    • v.28 no.10
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    • pp.1614-1625
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    • 2018
  • Periodontitis, which is a severe inflammatory disease caused by endotoxins secreted from oral pathogens, destructs gingival tissue and alveolar bone. Curcuma xanthorrhiza, commonly called Java turmeric, has been shown to possess anti-bacterial and anti-inflammatory activities. The present study evaluated the inhibitory effect of C. xanthorrhiza supercritical extract (CXS) standardized with xanthorrhizol on lipopolysaccharide (LPS)-induced periodontitis in an animal model. LPS was topically injected into the periodontium of Sprague-Dawley rats to induce periodontitis and CXS (30 and $100mg{\cdot}kg^{-1}{\cdot}day^{-1}$) was orally administered after day 12. Histologically, CXS inhibited the collapse of gingival tissue by preventing cell infiltration. CXS significantly downregulated the expression of matrix metalloproteases (MMPs) and inflammation-related biomarkers, such as nuclear factor-kappa B ($NF-{\kappa}B$) and interleukin-1 beta ($IL-1{\beta}$) in gingival tissue. CXS also improved bone remodeling by downregulating osteoclastic transcription factors, such as nuclear factor of activated T-cells c1 (NFATc1), tartrate-resistant acid phosphatase (TRAP), and cathepsin K. In addition, CXS upregulated osteoblast differentiation-related markers, alkaline phosphate (ALP) and collagen type I alpha (COLA1). Thus, CXS can ameliorate periodontitis by inhibiting inflammation and improving bone remodeling.

SENSITIVITY ANALYSES OF THE USE OF DIFFERENT NEUTRON ABSORBERS ON THE MAIN SAFETY CORE PARAMETERS IN MTR TYPE RESEARCH REACTOR

  • Kamyab, Raheleh
    • Nuclear Engineering and Technology
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    • v.46 no.4
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    • pp.513-520
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    • 2014
  • In this paper, three types of operational and industrial absorbers used at research reactors, including Ag-In-Cd alloy, $B_4C$, and Hf are selected for sensitivity analyses. Their integral effects on the main neutronic core parameters important to safety issues are investigated. These parameters are core excess reactivity, shutdown margin, total reactivity worth of control rods, thermal neutron flux, power density distribution, and Power Peaking Factor (PPF). The IAEA 10 MW benchmark core is selected as the case study to verify calculations. A two-dimensional, three-group diffusion model is selected for core calculations. The well-known WIMS-D4 and CITATION reactor codes are used to carry out these calculations. It is found that the largest shutdown margin is gained using the $B_4C$; also the lowest PPF is gained using the Ag-In-Cd alloy. The maximum point power densities belong to the inside fuel regions surrounding the central flux trap (irradiation position), surrounded by control fuel elements, and the peripheral fuel elements beside the graphite reflectors. The greatest and least fluctuation of the point power densities are gained by using $B_4C$ and Ag-In-Cd alloy, respectively.

Ginsenoside Rg2 inhibits osteoclastogenesis by downregulating the NFATc1, c-Fos, and MAPK pathways

  • Sung-Hoon Lee;Shin-Young Park;Jung Ha Kim;Nacksung Kim;Junwon Lee
    • BMB Reports
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    • v.56 no.10
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    • pp.551-556
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    • 2023
  • Ginsenosides, among the most active components of ginseng, exhibit several therapeutic effects against cancer, diabetes, and other metabolic diseases. However, the molecular mechanism underlying the anti-osteoporotic activity of ginsenoside Rg2, a major ginsenoside, has not been clearly elucidated. This study aimed to determine the effects of ginsenoside Rg2 on receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation. Results indicate that ginsenoside Rg2 inhibits RANKL-induced osteoclast differentiation of bone marrow macrophages (BMMs) without cytotoxicity. Pretreatment with ginsenoside Rg2 significantly reduced the RANKL-induced gene expression of c-fos and nuclear factor of activated T-cells (Nfatc1), as well as osteoclast-specific markers tartrate-resistant acid phosphatase (TRAP, Acp5) and osteoclast-associated receptor (Oscar). Moreover, RANKL-induced phosphorylation of mitogen-activated protein kinases (MAPKs) was decreased by ginsenoside Rg2 in BMM. Therefore, we suggest that ginsenoside Rg2 suppresses RANKL-induced osteoclast differentiation through the regulation of MAPK signaling-mediated osteoclast markers and could be developed as a therapeutic drug for the prevention and treatment of osteoporosis.

EFFECTS OF NITRIC OXIDE SYNTHASE INHIBITORS ON OSTEOCLAST-LIKE CELL FORMATION

  • Ahn, Seung-Kyu;Kim, Jung-Kun;Cha, Kyung-Suk
    • The korean journal of orthodontics
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    • v.25 no.6 s.53
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    • pp.715-722
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    • 1995
  • Orthodontic tooth movement in response to orthodontic force results from actions of osteoclasts and osteeoblasts in the cell level. Convincing evidence has now been provided to support the view that osteoclasts are derived from mononuclear cells that originate in the bone marrow or other hematopoietic organs and they migrate to the bones via vascular routes. Nitric oxide(NO), which accounts for the biological properties of endothelium-derived relaxing factor(EDRF), is the endogenous stimulator of soluble guanylate cylase. The discovery of the formation of nitric oxide(NO) from L-arginine in mammalian tissues and its biological roles has, in the last 7 years, thrown new light onto many areas of research. Data from experiments in vitro showed that N-metyl-L-arginine(L-NMA) and L-nitro-L- arginine(L-NAME) are competitive inhibitors of nitric oxide synthase. This study suggest that the multinucleated cells in our culture have characteristics of osteoclasts and that the potential bone cell activity of nitric oxide in vitro may be mediated in part by stimulation of marrow mononuclear cells to form osteoclast-like cells. Bone marrow cells were obtaineed from tibia of 19-days old chick embryo. After sacrifice, tibia was quickly dissected and the bone were then split to expose the medullary bone. The cells were attached for 4 hours and the nonadherent cells were collected. Marrow cells weere cultured in 96-well plate in medium 199. To examine the number of TRAP-positive multinucleated cells(MNCs), $10^{-8}\;M\;Vit=D_3$ and various concentration of L-NMA and L-NAME weere added at the beginning of cultures and with each medium change. After 7 days of culture. tartrate-resistant acid phosphatase(TRAP) staining was performed for microscopic evaluation. Cells haying more than three nuclei per cell were counted as MNCs. The obsrved results were as follows;1. 1,25-dihydroxyvitamine $D_3$ stimulated the osteoclast-like multinucleated cells in cultures of chick embryo bone marrow. 2. Nitric oxide synthase inhibitors(NOSI ; N-NMA, N-NAME) stimulated the osteoclast-like cells in cultures of chick embry bone marrow. 3. 1,25-dihydroxyvitamine$D_3$ and nitric oxide synthase inhibitors did not appear to have additive effect on the generation of TRAP-positive MNCs. These results suggest that nitric oxide synthase inhibitors may stimulate the osteoclast-like multinucleated cell formation and fusion in cultures of chick bone marrow.

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Response of Wild Boars (Sus scrofa) to Two Attractants, and Use of Cage Traps to Capture Wild Boars in Korea (대한민국에서 멧돼지 포획을 위한 두 가지 유인먹이에 대한 반응과 상자형 포획트랩 이용)

  • Song, Jang-Hoon;Choi, Eu-Ddeum;Seo, Ho-Jin
    • Korean Journal of Organic Agriculture
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    • v.26 no.3
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    • pp.381-391
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    • 2018
  • This study was carried out to determine whether cage traps can be used to capture wild boars successfully, and to assess their response to different bait materials and the number of wild boars caught. Steel cage-traps ($4.0m{\times}1.5m{\times}1.2m$, $L{\times}W{\times}H$) were installed at two sites in Damyang County and at one site in Sunchang County, South Korea. To identify preferred bait-diet, baits were prepared with dry corn and fermented sour corn and placed in equal amounts at the sites close to wild boar pads at 200 m intervals. Before selecting trap locations where sufficient activity was observed, pre-baiting was undertaken and steel-framed traps were installed with gates open. Preference for bait materials was not clearly defined. After providing the bait for the first time, the number of days until wild boars ate all the food were counted. In the Damyang and Youngam areas, where hunting was allowed, total bait consumption took 6 to 12 days; in contrast, in the Sunchang area, where no hunting took place, total food consumption took only 5 days. In addition, after pre-baiting with the mixture of dry and sour corn for diet for about 8.7 days and then opening the trap gates for 3 more days, 13.7 days were necessary to catch 4.3 wild boars per trap. These results suggest that hunting intensity around trapping places was an important factor in determining the success of the traps.

Conditioned Medium of Soybean Extract Treated Osteoblasts Inhibits RANKL Induced Differentiation of Osteoclasts (대두추출물을 처리한 조골세포 조건배양액은 RANKL에 의해 유도된 파골세포 분화를 억제)

  • Park, Kyung-Ho;Ju, Won-Chul;Yeo, Joo-Hong;Lee, Kwang-Gill;Cho, Yun-Hi
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.1
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    • pp.64-70
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    • 2010
  • Soybean is of particular interest as a food supplement of isoflavones for inhibiting bone resorption in postmenopausal woman. These beneficial effects of isoflavones are caused by functioning as partial agonists or antagonists of estrogen, of which anti-resorptive effect is mediated indirectly through paracrine factors produced by osteoblasts that act on osteoclasts. In this study, the indirect effect of soybean on osteoclastic differentiation of RAW264.7 cells were investigated. The conditioned medium was collected from MC3T3-E1 osbeoblasts treated with 0.001 mg/mL~0.1 mg/mL soybean extracts for 6 days, mixed in 1:1 ratio with osteoclast medium, and then added into RAW264.7 cells with receptor activator of nuclear factor kappa B ligand (RANKL), a differentiation inducer for 3 days. Of paracrine factors in the conditioned medium, the protein expression of osteoprotegerin (OPG) with soybean extract was specifically higher in a dose dependent manner than with $10^{-9}$ M~$10^{-6}$ M of estrogen, genistein or daidzein standards. In RAW264.7 cells, the conditioned medium with soybean inhibited RANKL induced osteoclastic differentiation as total number of multinucleated tartrateresistant alkaline phosphatase (TRAP)-positive osteoclasts and protein expression of MMP-9 were significantly decreased. Coupled with the low expression of estrogen receptor $\alpha$ and $\beta$ proteins in RANKL treated RAW264.7 cells, we demonstrate that the conditioned medium of soybean treated osteoblasts inhibits RANKL induced differentiation of osteoclasts with the selective expression of OPG in osteoblasts.

An investigative study of enrichment reduction impact on the neutron flux in the in-core flux-trap facility of MTR research reactors

  • Xoubi, Ned;Darda, Sharif Abu;Soliman, Abdelfattah Y.;Abulfaraj, Tareq
    • Nuclear Engineering and Technology
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    • v.52 no.3
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    • pp.469-476
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    • 2020
  • Research reactors in-core experimental facilities are designed to provide the highest steady state flux for user's irradiation requirements. However, fuel conversion from highly enriched uranium (HEU) to low enriched uranium (LEU) driven by the ongoing effort to diminish proliferation risk, will impact reactor physics parameters. Preserving the reactor capability to produce the needed flux to perform its intended research functions, determines the conversion feasibility. This study investigates the neutron flux in the central experimental facility of two material test reactors (MTR), the IAEA generic10 MW benchmark reactor and the 22 MW s Egyptian Test and Research Reactor (ETRR-2). A 3D full core model with three uranium enrichment of 93%, 45%, and 20% was constructed utilizing the OpenMC particle transport Monte Carlo code. Neutronics calculations were performed for fresh fuel, the beginning of life cycle (BOL) and end of life cycle (EOL) for each of the three enrichments for both the IAEA 10 MW generic reactor and core 1/98 of the ETRR-2 reactor. Criticality calculations of the effective multiplication factor (Keff) were executed for each of the twelve cases; results show a reasonable agreement with published benchmark values for both reactors. The thermal, epithermal and fast neutron fluxes were tallied across the core, utilizing the mesh tally capability of the code and are presented here. The axial flux in the central experimental facility was tallied at 1 cm intervals, for each of the cases; results for IAEA 10 MW show a maximum reduction of 14.32% in the thermal flux of LEU to that of the HEU, at EOL. The reduction of the thermal flux for fresh fuel was between 5.81% and 9.62%, with an average drop of 8.1%. At the BOL the thermal flux showed a larger reduction range of 6.92%-13.58% with an average drop of 10.73%. Furthermore, the fission reaction rate was calculated, results showed an increase in the peak fission rate of the LEU case compared to the HEU case. Results for the ETRR-2 reactor show an average increase of 62.31% in the thermal flux of LEU to that of the HEU due to the effect of spectrum hardening. The fission rate density increased with enrichment, resulting in 34% maximum increase in the HEU case compared to the LEU case at the assemblies surrounding the flux trap.

Characterization of Hot Carrier Mechanism of Nano-Scale CMOSFETs (나노급 소자의 핫캐리어 특성 분석)

  • Na Jun-Hee;Choi Seo-Yun;Kim Yong-Goo;Lee Hi-Deok
    • Proceedings of the IEEK Conference
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    • 2004.06b
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    • pp.327-330
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    • 2004
  • It is shown that the hot carrier degradation due to enhanced hot holes trapping dominates PMOSFETs lifetime both in thin and thick devices. Moreover, it is found that in 0.13 ${\mu}m$ CMOSFET the PMOS lifetime under CHC (Channel Hot Carrier) stress is lower than the NMOSFET lifetime under DAHC (Drain Avalanche Hot Carrier) stress. Therefore. the interface trap generation due to enhanced hot hole injection will become a dominant degradation factor. In case of thick MOSFET, the degradation by hot carrier is confirmed using charge pumping current method and highly necessary to enhance overall device lifetime or circuit lifetime in upcoming nano-scale CMOS technology.

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Effects of Baicalin on the differentiation and activity of preosteoclasts

  • Ko, Seon-Yle
    • International Journal of Oral Biology
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    • v.34 no.2
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    • pp.81-86
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    • 2009
  • Baicalin is a flavonoid purified from the medicinal plant Scutellaria baicalensis. It has been reported that baicalin exhibits antibacterial, anti-inflammatory and analgesic effects. The present study was undertaken to determine the underlying cellular mechanisms of baicalin action in preosteoclasts. The effects of this flavonoid on preosteoclasts were determined by measuring osteoclast generation and osteoclast activity in macrophage-colony stimulating factor (M-CSF)-dependent bone marrow cells (MDBMCs) and in co-cultures of MDBMCs and osteoblasts. Osteoclast generation was assayed by measuring the number of tartrateresistant acid phosphatase (TRAP) (+) multinucleated cells after culture. Osteoclast activity was assayed by measuring the area of the resorption pit after culture. We found that osteoclast generation was induced by M-CSF and receptor activator of NF-kB ligand (RANKL), and by the 1.25-dihydroxycholecalciferol in our cultures. Baicalin decreased both osteoclast generation and activity in MDBM cultures and co-cultures indicating that it may inhibit bone resorption.

The effect of taurine and alendronate on the osteoclast differentiated by the sonicated extracts of Porphyromonas Gingivalis in vitro

  • Kim, Hyung-Su;Lee, Seung-Jong;Lee, Chan-Young;Kum, Kee-Yeon
    • Proceedings of the KACD Conference
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    • 2001.11a
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    • pp.566.2-566
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    • 2001
  • The objective of this study was to investigate the ability of alendronate and taurine in inhibiting in vitro osteoclast differentiation induced by bacteria. Whole cell sonicates of P. gingivalis were used as an osteoclast-stimulating factor in a mouse coculture system and differentiated osteoclasts were confirmed by tartrate-resistant acid phosphatase (TRAP) staining. Alendronate at the concentrations of 10-7, 10-6, and 10-5 M, and taurine at the concentrations of 4mM, 8mM, and 12mM were used.(omitted)

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