• Journal of IKEEE
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• v.3 no.2 s.5
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• pp.196-203
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• 1999

In this paper, the DS(direct sequence)-CDMA and MC(multi-carrier)-CDMA, which are being researched recently as a synchronous IMT-2000 scheme for next-generation mobile multimedia communications, are studied in terms of BER(bit error rate) performance. The BER performance of MC-CDMA with EGB, MRC, and improved MMSEC detection scheme are analyzed and compared to that of conventional DS-CDMA adopting RAKE receiver through the computer simulations under the environments of synchronous IMT-2000 transmission channel. Not only single user case but also multiuser case is considered in the given system. As a result, it is shown that MC-CDMA with MMSEC detection outperforms all other schemes improved the $E_b/N_o$ by about 5 [dB] and 6 [dB] when the BER is $2{\times}10^{-3}$, for the indoor/outdoor fading channel and synchronous IMT-2000 transmission channel, respectively. Also in the multiuser case, MC-CDMA with MMSEC detection scheme exhibits better performance than all the other schemes.

• Journal of Applied Biological Chemistry
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• v.64 no.3
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• pp.263-268
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• 2021

7-Hydroxy-4-methylcoumarin (7H-4MC) inhibits hyaluronan production in multiple cell lines and tissue types both in vitro and in vivo. It is a commercially available drug approved for human use, called hymecromone, in European and Asian countries to prevent biliary spasms. Nevertheless, as the pharmacological efficacy of 7H-4MC has not yet been reported in macrophages, this study investigated its anti-inflammatory effects and mechanism of action using lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. LPS-induced RAW 264.7 cells were treated with various concentrations of 7H-4MC (62.5, 125, 250, and 500 μM). The application of 7H-4MC significantly reduced nitric oxide and prostaglandin E₂ production without cytotoxic effects. Additionally, 7H-4MC strongly decreased the expression of inducible nitric oxide synthase and cyclooxygenase. Furthermore, 7H-4MC reduced the production of proinflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-1β, and IL-6. Finally, 7H-4MC exerted its potent anti-inflammatory actions via the upregulation of IκB-α production, which led to the inhibition of nuclear factor-κB (NF-κB) activity. These results, obtained in macrophage cell lines, suggest that 7H-4MC prevents inflammatory diseases via the NF-κB signaling pathway and that its use could be beneficial for human health. Ultimately, this is the first report describing the anti-inflammatory activity of 7H-4MC in a macrophage cell line.

• The korean journal of orthodontics
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• v.26 no.4
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• pp.449-454
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• 1996

The propose of this study was to evaluate the difference of cellular activity dependent on intermittent compressive force by determining the alkaline phosphatase activity. Alkaline phosphatase activity was measured on control and experimental groups every 24, 48, 72hours. Experimental groups consisted of continous and intermittent compressive group which were compressed by $300gm/cm^2$ of diaphram pump. The intermittent compressive group was connected by timer which was worked on 10 minutes an off 10 minutes. The results were as follows; 1. The alkaline phosphatase activity between control and experimental groups showed not significant difference at compressed 24 hours. 2. The alkaline phosphatase activity of experimental groups were more increased than control group at compressed 48 hours. 3. The alkaline phosphatase activity of intermittent compressive group showed significant increased to control group. Whereby continuous compressive group showed not significant difference to control at 72 hours. 4. The alkaline phosphatase activity of intermittent compressive group were stringly increased than continuous compressive groups. 5. Between experimental groups and control group no other morphologic changes were detected by microscopic findings.

• The korean journal of orthodontics
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• v.27 no.6 s.65
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• pp.929-941
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• 1997

Optimal force for orthodontic treatment is the force that produces a rapid rate of tooth movement without discomfort to the Patient or ensuing tissue damage. Recently considerable interest has been generated in the application of magnets as a way to obtain an optimal force. The purpose of the present study was to investigate the effect of static magnetic fields of Sm-Co magnets on molecular and cellular activities. The distance of erythrocyte sedimentation was measured directly, and the activities and the syntheses of $Fe^{2+}$-related enzymes (catalase and NO synthase) and non $Fe^{2+}$-related enzyme (lactic dehydrogenase) were assayed by the spectrophotometer. The growth and the proliferation of osteoblast-like cells $MC_3T_3-E_1$ were determined by the crystal violet staining and the ${^3}H$-thymidine incorporation. The erythrocytes were exposed to the pole face flux density of 1,400 G (gauss), and the enzymes and osteoblast-like cells $MC_{3}T_3-E_1$ were exposed to the flux density of 7,000 G. The results obtained were as follows: 1. The distance of sedimentation of erythrocyte was not affected by the static magnetic fields. 2. The activities of catalase and lactic dehydrogenase were not affected by the static magnetic fields. 3. The intracellular syntheses of NO synthase and lactic dehydrogenase were not affected by the static magnetic fields. 4. The growth and the proliferation of cultured osteoblast-like cells $MC_{3}T_3-E_1$ were not affected by the static magnetic fields. These results suggested that the molecular and cellular activities were not significantly influenced by the static magnetic fields.

• International Journal of Oral Biology
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• v.33 no.3
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• pp.105-111
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• 2008

Thrombospondins (TSP-1, TSP-2) are secretory extracellular glycoproteins that are involved in a variety of physiological processes such as tumor cell adhesion, invasion, and metastasis. The present study was undertaken to elucidate the involvement of thrombospondins in the adhesion of osteoblast-like cells using the TSP-1 or TSP-2 antisense MG63 and MC3T3-E1 cell lines. For downregulation of TSPs expression, we prepared antisense constructs for TSP-1 and TSP-2 using the pREP4 an episomal mammalian expression vector, which be able to produce the specific antisense oligonucleotides around chromosome. MG63 and MC3T3-E1 osteoblast-like cells were transfected with the antisense constructs and nonliposomal Fugene 6, and then selected under hygromycin B (50 ${\mu}g/ml$) treatment for 2 weeks. Western blot analysis revealed that expression of the TSP proteins was downregulated in the antisense cell lines. The cell adhesion assay showed that adhesive properties of TSP-1 and TSP-2 antisense MG63 cells on the polystyrene culture plate were reduced to 17% and 21% of the control cells, respectively, and those of the TSP-1 and TSP-2 antisense MC3T3-E1 cells also decreased to 19% and 27% of control, respectively. Adhesion of TSP-1 and TSP-2 antisense MC3T3-E1 cells on Type I collagen-coated culture plate decreased to 27% and 76%, respectively. These results indicate that TSP-1 and TSP-2 proteins may have an important role in adhesion of osteoblast-like cells to extracellular matrix.

• Journal of Periodontal and Implant Science
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• v.37 no.1
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• pp.115-124
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• 2007

Silica is known as a promising osteoconductive material, and polycaprolactone is a bioactive and degradable material. The purpose of this study was to monitor the differentiation of MC3T3-E1 cells cultured on the layer-built silica/poly caprolactone non-woven fabric produced by electrospinning. Non-woven fabric (silica, polycaprolactone, PSP, SPS) was made by electrospinning and they were inserted in the 48 well cell culture plate. MC3T3-E1 cells were prepared by subculture. Cells were seeded to each well $1{\times}10^5$ concentration per well. Dulbecco's modified eagle medium with 10% FBS and 1% antibiotic-antimycotic solution was used. Confocal laser scanning microscope was taken 4 hours after incubation (95% air. 5% $CO_2$, $37^{\circ}C$). Cell proliferation was monitored by spectrophotometer on 1, 7, 14 days, and the morphology of the growing cells was observed by field emission scanning electron microscope. To monitor the differentiation of osteoblasts on the materials, MC3T3-E1 cells were incubated in 48 well culture plate after seeding with the density of $1{\times}10^5$ concentration. Then ELISA kit & EIA kit were used on to assess osteocalcin and osteopontin expression respectively. The other conditions were the same as above. MC3T3-E1 cells were proliferated well on all of the materials. There were no statistical differences among them. The osteopontin expression of silica, PSP, SPS was significantly higher than other groups on day 3 (p/0,05), but after that time, there were no statistically signigicant differences. The osteocalcin expression was significantly higher in silica and PSP than other groups on day 14. These findings show that PSP was as good as silica on the effect of osteoblast differentiation. The PSP non-woven fabric may have the possibility as bone graft materials.

• Journal of Periodontal and Implant Science
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• v.29 no.4
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• pp.751-765
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• 1999

Several growth factors and polypeptidesare not commonly yet used for regenerators of bone tissue or alveolar bone because of the insufficiency of studies on their side effects, genetic engineering for mass production and stability for clinical application. Recently, many natural medicines, which have advantage of less side effects and possibility of long-term use, have been studied for their capacity and effects of anti-bacterial, anti-inflammatory and regenerative potential of periodontal tissues. Olibanum, Myrrha, Phlomis Radix, and Cimicifugae Rhizoma have been traditionally used as a drug for treatment of bone disease in oriental medicine. The objective of this study was to examine the ability of alkaline phosphatase(ALP) synthesis of rat calvarial osteoblast(MC3T3-E1) when several natural medicines were supplemented. MC3T3-E1 cells were cultured with ${\alpha}$-MEM(negative control), dexamethasone(positive control), and each natural medicines for 3 and 5 days. And then ALP synthesis was measured by spectrophotometer for enzyme activity and by naphthol AS-BI staining for morphometry. All of the natural medicines induced higher activity of ALP synthesis than the negative controls. Especially Olibanumind uced the higher activity than the positive controls (p<0.05). In the aspects of culturing time, except Cimicifugae Rhizoma, the natural medicines induced higher activity of ALP synthesis at 5 days than at 3 days (p<0.05). In morphometry, all of the natural medicines showed statistical significance compared to the negative control (p<0.05). Myrrha a n d Phlomis Radix showed larger positively stained area at 5days than at 3 days, whereas the others did not showed the difference between at 5 and at 3 days(p<0.05). These results indicate that several natural medicines have an inducing ability of ALP synthesis in MC3T3-E1 cells.

• Natural Product Sciences
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• v.11 no.2
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• pp.103-108
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• 2005

Bioflavone quercetin is thought to have an important role to inhibit bone loss by affecting osteoclastogenesis and regulating a number of systemic and local factors such as hormones and cytokines. In this study, we examined how quercetin acts on cytokine production and mineralization of osteoblast in the presence of tumor necrosis factor-alpha $(TNF-{\alpha})$ which has been known to play a pivotal role in bone metabolic diseases. Quercetin inhibited $TNF-{\alpha}-induced$ secretion of $IFN-{\gamma}$ and IL-6 in differentiated MC3T3-E1 cells. As indicated by the markers that are characteristics of the osteoblast phenotype, such as alkaline phosphatase (ALP) activity and calcium deposition, quercetin treatment slightly prevented the $TNF-{\alpha}-induced$ dramatic inhibition of differentiation and mineralization of MC3T3-E1 cells. Further, quercetin inhibited the production of nitric oxide induced by $TNF-{\alpha}$ in the cells. Collectively, our findings indicate that quercetin inhibites $TNF-{\alpha}-induced$ secretion of inflammatory cytokines in differentiated MC3T3-E1 cells without any cytotoxic effects.

• Imaging Science in Dentistry
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• v.38 no.3
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• pp.125-132
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• 2008

Purpose : To investigate the effects of irradiation on transforming growth factor ${\beta}_1$ (TGF-${\beta}_1$) mRNA expression and calcific nodule formation in MC3T3-E1 osteoblastic cell line. Materials and Methods : Cells were cultured in alpha-minimum essential medium ($\alpha$-MEM) supplemented with 10% fetal bovine serum and antibiotics. When the cells reached the level of 70-80% confluence, culture media were changed with $\alpha$-MEM supplemented with 10% FBS, 5 mM $\beta$-glycerol phosphate, and $50\;{\mu}g/mL$ ascorbic acid. Thereafter the cells were irradiated with a single dose of 2, 4, 6, 8 Gy at a dose rate of 1.5 Gy/min. The expression pattern of TGF-${\beta}_1$ mRNA, calcium content and calcific nodule formation were examined on day 3, 7, 14, 21, 28, respectively, after the irradiation. Results : The amount of TGF-${\beta}_1$ mRNA expression decreased significantly on day 7 after irradiation of 4, 6, 8 Gy. It also decreased on day 14 after irradiation of 6, 8 Gy. and decreased on day 21 after irradiation of 8 Gy. The amount of calcium deposition decreased significantly on day 7 after irradiation of 4, 8 Gy (P < 0.01) and showed a decreased tendency on day 14, 21 after irradiation of 4, 6, 8 Gy. The number of calcific nodules was decreased on day 7 after irradiation of 4, 8 Gy. Conclusion: Irradiation with a single dose of 4, 6, 8 Gy influences negatively the bone formation at the molecular level by affecting the TGF-${\beta}_1$ mRNA expression that was associated with proliferation and the production of extracellular matrix in MC3T3-E1 osteoblastic cell line.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.82-88
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• 2012

Chrysanthemum indicum L. (Asteraceae) is a traditional herbal medicine that has been used for the treatment of inflammation, hypertension, and respiratory diseases due to its strong antagonistic activity against inflammatory cytokines. The effects of Chrysanthemum indicum L. Extract (CIE) for increasing cell growth, alkaline phosphatase (ALP) activity, and collagen content were totally inhibited, suggesting that the effect of CIE might be partly involved with estrogen activity. Furthermore, the protective effects of CIE on the response of osteoblasts to oxidative stress were evaluated. Osteoblastic MC3T3-E1 cells were incubated with hydrogen peroxide and/or CIE, and markers of osteoblast function and oxidative damage were examined. CIE significantly increased cell survival, ALP activity, and calcium deposition, and decreased the production of Reactive Oxygen Species (ROS) and Tumor Necrosis Factor-${\alpha}$ (TNF-${\alpha}$) in osteoblasts. Taken together, these results indicate that the enhancement of osteoblast function by CIE may prevent osteoporosis and inflammatory bone diseases.