• The Journal of Korean Obstetrics and Gynecology
• /
• v.25 no.3
• /
• pp.16-26
• /
• 2012

Objectives: This study was performed to evaluate effects of Cordyceps militaris(CM) on osteoclast differentiation and its related gene expression. Methods: We used mouse myeloid cells RAW 264.7 stimulated by receptor activator of nuclear factor kappa-B ligand(RANKL) to induce osteoclast differentiation. There are four groups of which RAW 264.7 cells are not stimulated by RANKL (Normal), stimulated by RANKL without CM(Control), stimulated by RANKL with 0.1 ${\mu}g/ml$ of CM(CM 0.1), stimulated by RANKL with 1 ${\mu}g/ml$ of CM(CM 1). Osteoclastogenesis was measured by counting Tartrate-resistant acid phosphatase-positive multinucleated cells [TRAP(+) MNC]. RT-PCR was performed to evaluate the inhibitory effect of CM on gene expression(TRAP, AKT1, JNK1, NFATc1, c-Fos, MITF). Results: 1. CM decreased the number of TRAP(+) osteoclast in RANKL-stimulated RAW 264.7 cell at the concentration of 0.1 ${\mu}g/ml$ and 1 ${\mu}g/ml$. 2. CM decreased the expression of TRAP in osteoclast at the concentration of 1 ${\mu}g/ml$. 3. CM decreased the expression of AKT1, JNK1 in osteoclast at the concentration of 1 ${\mu}g/ml$. 4. CM didn't affect the expression of NFATc1, c-Fos, MITF in osteoclast. Conclusions: Cordyceps militaris has inhibitory effects on osteoclast differentiation and its related gene expression. These results suggest that Cordyceps militaris has a potential as a treatment of osteoporosis.

• Journal of Korean Medicine Rehabilitation
• /
• v.29 no.2
• /
• pp.135-147
• /
• 2019

Objectives This study was performed to evaluate the effect of Pyrola japonica extract (NJ) and its principal constituent, homoarbutin (HA) on osteoclast differentiation and gene expression and bone resorption. The osteoclastogenesis and gene expression were determined in receptor activator of nuclear factor kappa B ligand (RANKL)-stimulated RAW264.7 cell. Methods In order to evaluate the effect of HA extracted from NJ on bone resorption, osteoclasts were used to be differentiated and formed by stimulating RAW264.7 cells with RANKL. Tartarate-resistant acid phosphatase (TRAP) (+) polynuclear osteoclast formation ability was evaluated, and differentiation control genes including cathepsin K, matrix metalloproteinases-9 (MMP-9), and TRAP in osteoclast differentiation were analyzed by real-time polymerase chain reaction (PCR). Immunoblotting was performed to measure the effect of mitogen-activated protein kinase (MAPK) factors on bone resorption, and the effect of osteoclasts on osteoclast differentiation was measured. Results Both NJ and high concentration of HA blocked RANKL-stimulated differentiation from RAW264.7 cell to TRAP-positive multinucleated cells. NJ reduced RANKL-induced expression of TRAP, cathepsin K. Both NJ and high concentration of HA inhibited RANKL-mediated expression of MMP-9, nuclear factor of activated T-cells, cytoplasmic 1, and cellular Jun-fos. NJ suppressed RANKL-stimulated expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase, tumor necrosis factor-alpha, and levels of interleukins. Both NJ and HA decreased bone resorption in osteoclast-induced bone pit formation model. Conclusions These results suggest that NJ and HA blocked bone resorption by decreasing RANKL-mediated osteoclastogenesis through down-regulation of genes for osteoclast differentiation.

• Journal of the Korean Applied Science and Technology
• /
• v.38 no.1
• /
• pp.168-177
• /
• 2021

The effects of the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture on the activities of osteoblast differentiation and the restraint of osteoclast formation were investigated. the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture in the human osteoblast "MG-63" cell, was examined in relation to alkaline phosphatase (ALP) activity and alizarin red stains. In order to observe the effects of osteoclasts formation, we analyzed RAW 264.7 cell tartrate-resistant acid phosphatase (TRAP) activity and TRAP stains. In cytotoxicity testing, it was confirmed that apple extract is safe at a concentration of 50 ㎍/㎖ or less. The ALP activity and Bone calcification formation ability were the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture had a lower activity than that of control group. However the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture significantly reduced activity of TRAP in the RAW 264.7 osteoclastic cell generation and effectively Inhibited the TRAP(+) multinuclear cells. Thus, our results demonstrate that the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture enhances the inhibitory activity of bone-resorption in RAW 264.7 cells. In conclusion, the Perilla frutescens var. crispa and Atractylodes macrocephala Koidzumi mixture seem to be effective in the prevention and treatment of bone related disorders.

• Proceedings of the KIEE Conference
• /
• 1999.11d
• /
• pp.932-934
• /
• 1999

In this paper, the new IGBT structures with trap injection are proposed to improve switching characteristics of the conventional SOI LIGBT. The simulations are used in order to investigate the effects of the position, width and concentration of trap injection region using 2D device simulator MEDICI. And, their electrical characteristics are analyze and the optimum design parameters are extracted. As a result of simulation, the turn off time for the proposed LIGBT model A by the trap injection is $0.78{\mu}s$. And, the latch up voltage is 3.4V and forward blocking voltage is 168V which are superior to that of conventional structure. In addition, the proposed model is achieved more efficient in switching time and process effort. Therefore, It is shown that the trap injection is very effective to reduce the turn off time with a little increasing of on-state voltage drop if its design and process parameters are optimized.

• The korean journal of orthodontics
• /
• v.31 no.3 s.86
• /
• pp.357-367
• /
• 2001

The purpose of this study was to investigate the alveolar bone turnover in diabetic rat, and to compare the alveolar bone turnover during tooth movement in diabetes with that in normal control Eighty Male Sprague-Dawley strain rats(8th week) were divided into normal control(N), normal-tooth movement (N-tm), diabetes(D), and diabetes-tooth movement(D-tm) groups. Eighteen days before the start of the experiment, diabetes was induced with a single injection of streptozotocin 50 mg/kg of body weight in citrate buffer as vehicle via the tail vein. Maxillary first molars of rats were moved mesially by 40 grams of the closed coil spring. Experimental animals were sacrificed after 1d, 3d, 7d, and 14d experimental period, and the alveolar bone around the maxillary first molars were assayed biochemically for acid phsophatase(ACP) and tartrate-resistant acid phosphatase (TRAP) as bone resorption markers, and alkaline phosphatase(ALP) and osteocalcin(OC) as bone formation markers. TRAP and OC concentration in serum and alveolar bone of D group were lower than those in N group, and especially OC concentration decreased mote following diabetes prolonged, which showed the decreased skeletal and alveolar bone resorption and formation potential in diabetic rats. In N-tm group compared with N group, alveolar bone ACP and TRAP concentrations were highest at 1d and 3d(p<0.01), decreased after then, and showed lowest at 14d, and alveolar bone OC concentration was higher at 3d, 7d, and 14d(p<0.001) and showed a tendency of peak level at 7d. which showed the peak of concentration of bone resorption markets at 1d-3d and those of bone formation markers at 7d. In D-tm group compared with N group, alveolar bone ACP and TRAP concentrations were higher at 3d, 7d and 14d(p<0.001), and tended to reach peak value at 7d and persisted through 14d, and alveolar bone ALP and OC concentration increased but not different from that of N group. The amount of tooth movement in D group were greater than that of N group at all experimental period. Those results were suggested that during diabetes, the alveolar and skeletal bone undergo low bone turnover and the mote amount of tooth movement, hut because the peak time of alveolar bone resorption activity was delayed and sustained in longer period of tooth movement and alveolar bone formation activity is lower than that of normal tooth movement, the periodontal space is supposed to be larger doting tooth movement.

• Analytical Science and Technology
• /
• v.10 no.5
• /
• pp.332-342
• /
• 1997

Fifteen volatile organic pollutants were spiked in blank water at the concentration of $20{\mu}g/L$ and analyzed with Purge and Trap and GC/MS. As a result, the overall mean recovery of 100% was obtained with a mean relative standard deviation of 3.6%. The method detection limits were in the range of $1.9{\sim}3.3{\mu}g/L$. In the wastewater analysis of Banwol dyeing comlex, 15 organic compounds were identified and three of these were quantified. Among the compounds identified, only trichloroethylene and tetrachloroethylene are regulated in wastewater by the Korea Ministry of Environment. But, the concentration of these two compounds were below the government allowance level.

• Journal of the Korean Ceramic Society
• /
• v.28 no.2
• /
• pp.141-145
• /
• 1991

The effects of the melt stoichiometry on the concentration of electron and hole traps formed by intrinsic defects of LEC GaAs were studied employing DLTS measurement technique. The concentration of EL2 were varied from $10^{16}cm^{-3}$ to $10^{11}cm^{-3}$ when the arsenic atomic fraction in the melt ([As]/{[As]+[Ga]} varied from 0.5 to 0.42. Specifically, when the fraction falls below 0.46, the 띠2 concentration start to decrease sharply. For 68meV and 77/200meV traps, their concentration increase inversely with the arsenic atomic fraction and have the values in the range of TEX>$10^{15}cm^{-3}$ and $10^{14}cm^{-3}$, respectively. It is, therefore, concluded that these hole traps originated from the intrinsic acceptor defects including $GS^{AS}$.

• ETRI Journal
• /
• v.15 no.2
• /
• pp.11-25
• /
• 1993

Interface trap densities at gate oxide/silicon substrate ($SiO_2/Si$) interfaces of metal oxide semiconductor field-effect transistors (MOSFETs) were determined from the substrate bias dependence of the subthreshold slope measurement. This method enables the characterization of interface traps residing in the energy level between the midgap and that corresponding to the strong inversion of small size MOSFET. In consequence of the high accuracy of this method, the energy dependence of the interface trap density can be accurately determined. The application of this technique to a MOSFET showed good agreement with the result obtained through the high-frequency/quasi-static capacitance-voltage (C-V) technique for a MOS capacitor. Furthermore, the effective substrate dopant concentration obtained through this technique also showed good agreement with the result obtained through the body effect measurement.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.54 no.1
• /
• pp.73-80
• /
• 2018

Intermittent duty of emergency generator has problems emitting large quantities of PM and NOx in exhaust gas. The aim of this study is to propose DPF system which can be applied to medium-large emergency generators. The system is composed of soot dust collector, silencer and filter trap, which is designed to reduce PM emissions at the emergency generator start-up. The pneumatic system controls a flow direction of exhaust gas to pass through the soot collector and filter trap until the engine reaches complete combustion condition. An experiment is performed to measure PM content and concentration to analyze the performance and characteristics of the proposed system.

• Analytical Science and Technology
• /
• v.8 no.4
• /
• pp.771-778
• /
• 1995

The authors have developed an analytical method for determining trace amounts of 285 kinds of chemicals in natural waters by GC-ion trap MS. The results of overall recovery tests at $0.1{\mu}g/l$ showed that the mean recovery was 92.1% and the mean relative standard deviation was 10.8%. The mean of the method detection limits was $0.036{\mu}g/l$. From the results of analysis of real samples, it was confirmed that this method is useful to elucidate the concentration levels and the fate of chemicals in the aquatic environment.