• Proceedings of the PSK Conference
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• 2002.10a
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• pp.244.2-245
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• 2002

4-Hydroxy nonenal (HNE) is a lipid peroxidation product derived from oxidized $\omega$-6 polyunsaturated fatty acids, such as arachidonic acid. HNE is widely used as a marker of lipid peroxidation. To study the hypothesis that HNE may induce apoptosis and cell cycle arrest, we estimated cytotoxicity of HNE in BAE (bovine aortic endothelial) cells. Anti-proliferative effects were examined by morphological changes and MTT assay after exposure to different time (0-3 hr) and concentration (3-7 ${\mu}$M of HNE. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.316.3-317
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• 2002

In previous reports, we exhibited that acteoside showed significant cytotoxicity against various cancer cells. In this study we investigated that acteoside is capable of inducing differentiation in HL -60 human leukemia cell line. After being treated with acteoside, the growth curve was decreased remakably in a dose- and time-dependent manner, and cell doubling time was delayed. Exposure of cells to 20 $\mu\textrm{g}$/m$\ell$ acteoside induced differentiation of HL-60 cells to monocyte/macrophage-like cells by cell surface antigen expression. The percentage of NBT reducing activity was increased in a time-dependent manner. In addition. the protein lever of p21 and p16 increased and ppRb decreased in western biot analysis. Theas results suggest that acleoside possess the activity of inducing differentiation in HL-60 cells.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.4
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• pp.37-46
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• 1996

In this paper, we analyzed the performance improvement of the DS-CDMA/dPSK cellular mobile communication system with CCI canceller and RAKE receiver techniques in mobile radio channel which is characterized by AWGN, Multi-user interference (mUI) and frequency-selective rayleigh fading. System capacity i.e., number of user per cell has been derived and the evaluated results are shown in figuraes as a function of PN code sequence length, number of RAKE receiver tap, BER and E$_{b}$/N$_{o}$. The voice activity factor is assumed to be 3/8 the number of sectors in a cell 3 and MUI is modeled as gaussian process. From the results, the capacity of the DS-CDMA/DPSK cellular mobile communication system is improved by adopting CCI canceller. When we adopt the RAKE receiver to mitigate the multipath fading, the error performance is improved and the amount of improvement is proportional ot the number of taps L in the case that each tap contains a signal component and the better of improvement can be obtained, the smaller of the SNR difference in each tap. The system capacity is more increased when the CCI canceller and the RAKE receiver is used in cascade.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.383.1-383.1
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• 2002

In connection with our studies on the isolation of hepatoprotective constituents from natural products. we have recently reported hepatoprotective compounds including phenolic bakuchiol. diarylheptanoids. furocoumarins. In the course of continuing efforts. the aqueous extract of the roots of Agrimonia pilosa Ledeb. (Rosaceae) was found to exhibit promising hepatoprotective activity. A. pilosa is a perennial herb distributed throughout South Korea. and its roots have been used as the hemostatic. antimalarial. and antidysenteric agent in oriental medicine. Chemical investigation of the aqueous extract of the roots of this plant. as guided by hepatoprotective active catechin (2). Compound 1 showed hepatoprotective effects on both tacrine-induced cytotoxicity in human level derived Hep G2 cells and tert-hydroperoxide-induced cytotoxicity in rat primary hepatocyles with $EC_{50}$ values of 66.2 $\pm$ 2.8 and 22.9 $\pm$ 2.6 $\mu\textrm{M}$ respectively.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.88.1-88.1
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• 2003

CJ-11668 is a new potent and selective COX-2 inhibitor (IC$\sub$50/ COX-2 65nM; COX-l/COX-2 ratio 770). The pharmacokinetic profile of CJ-11668 (20 mg/kg, p.o.) in the rat was characterized by high bioavailability (90%) and long plasma half-life (11.7 hr) with low clearance (0.4 L/hr/kg). In the dog, the PK profiles (2 mg/kg, p.o.) also showed long plasma half-life (l7.9hr) with low clearance (0.5 L/hr/kg), and the bioavalability of 60%. The inhibition of CJ-11668 infive different cytochrome P450 isozymes (1A2, 2C9, 2C19, 2D6 and 3A4) was determined in vitro and had observed no significant effect. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.115.1-115.1
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• 2003

Cadmium, a human carcinogen, can induce apoptosis in various cell lines. Despite extensive research, the mechanisms of cadmium-induced apoptosis are poorly understood, and its toxicity and estrogenic potential in human are not clear. This study was performed to investigate the apoptotic activities of cadmium on two human breast cancer cell lines: MCF-7 cells, an estrogen receptor (ER) positive cell line, and MDA-MB-231 cells, an ER negative cell line. Both cells were treated with $CdCl_2$ 100$\mu$M for 12hrs, and the spoptosis was determined by DNA fragmentation, DAPI staining, and expression of caspase-9. (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.222.1-222.1
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• 2003

This study was carried out to investigate the quality control of domestic and imported Puerariae Radix. It was analyzed by HPLC using ${\mu}$-Bondapak C$\sub$18/ column with 35% MeOH containing 1% CH$_3$3CO$_2$H system as the mobile phase at UV 254nm. Good linearity showed over the range of 10 to 200$\mu\textrm{g}$/$m\ell$(r$^2$=1) for Puerarin, and 0.5 to 10$\mu\textrm{g}$/mg(r$^2$=0.9999) for Daidzein. The average contents of Puerarin and Daidzein were 5.5${\pm}$1.2%(Domestic), 5.3${\pm}$0.7%(Imported), and 0.05${\pm}$0.02%(Domestic), 0.08${\pm}$0.02%(Imported).The average recovery rates of Puerarin and Daidzein were 101.8${\pm}$1.9% and 97.2${\pm}$0.7%, respectively.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.6 no.3
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• pp.36-54
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• 1995

The error performance of digital radio signals (i.e., M-ary PSK signal, DQPSK signal, MSK signal, GMSK signal) interfered by impulsive noise and electromagnetic interference (EMI) is analyzed and discussed. In analysis at first, the error rate equations have been derived in an electromagnetic interference plus impulsive noise environment. And then, the error performance has been evaluated and shown in figures as a function of carrier-to-noise ratio, carrier-to-interference ratio, impu- lsive index, gaussian noise to impulsive noise power ratio, and interference index to measure the amount of error degradation in digital radio signals. From the obtained results we have known that in the presence of m-distributed tone interference plus inpulsive noise, the more significant the electromagnetic interference amplitude varies, the more significant performance degradation is produced. The listing the digital radio signals from the most degraded to the least is that DQPSK, GMSK, QPSK and MSK signal. In the constant amplitude tone interference plus impulsive noise environment, the effect of in- terference nearly disappears over about 20dB in CIR. The effect of constant tone interference on error rate performance is reduced more remarkably in the region from 10dB to 15dB in CIR. In both enviroments of m-distributed tone interference and constant amplitude tone interference, the more electromagnetic interference amplitude varies and CIR increases, the more error perfor- mance is improved. But it is found out that the performance can not be improved significantly even the electromagnetic interference becomes weak. This describes that the impulsive noise affects dominantly to the performance degradation.

• YAKHAK HOEJI
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• v.59 no.5
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• pp.207-214
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• 2015

P2Y receptors, a type of P2 receptor family, are G-protein coupled receptors and 8 subtypes have been characterized ($P2Y_1$, $P2Y_2$, $P2Y_4$, $P2Y_6$, $P2Y_{11-14}$). Recently, several studies have shed light on the role of P2Y receptors in bone biology. Among them, little is known on the role of $P2Y_6$ receptor on osteoclast differentiation. Thus, we investigated the role of $P2Y_6$ receptor on osteoclastogenesis using $P2Y_6$ receptor selective antagonist, MRS 2578. When osteoblasts and bone marrow cells were co-cultured in the presence of $VitD_3$ and $PGE_2$, $P2Y_6$ antagonist increased the formation of TRAP positive osteoclasts. To elucidate the target cells of $P2Y_6$ antagonist, we first checked the effect of MRS 2578 on osteoblasts. Treatment of MRS 2578 did not affect OPG : RANKL mRNA ratio in osteoblasts. Next, we checked the effects of $P2Y_6$ antagonist on osteoclast precursors using mouse bone marrow macrophages (BMMs). Addition of MRS 2578 increased the number of osteoclasts in RANKL-treated BMMs. Although $P2Y_6$ antagonist had no effect on RANKL-induced NFATc1, c-Fos and MafB expression levels, it significantly stimulated RANKL-induced Blimp1 mRNA expression in BMMs. Taken together, these data indicate that $P2Y_6$ antagonist increases osteoclast formation by upregulation of Blimp1 expression.

• YAKHAK HOEJI
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• v.60 no.1
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• pp.36-45
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• 2016

This study was aimed to enhance the percutaneous absorption of tizanidine hydrochloride (TZ) across Strat-M$^{TM}$ artificial membrane and excised hairless mouse skin using various vehicles and chemical permeation enhancers. Solubility studies were performed using hydrophilic and lipophilic vehicles. To initially evaluate vehicle effects on skin permeation, Strat-M$^{TM}$ membrane was adopted using Franz-type diffusion cells loaded with 0.4 mg donor dose. Effects of fatty acids on the permeation of TZ from PG and PGMC were compared, and the effects of various hydrophilic vehicles in the presence of linoleic acid were studied using excised hairless mouse skin specimens. The mean solubility (mg/ml) of TZ in hydrophilic vehicles was higher: water > PG > DMSO > ethanol > PEG 200 > NMP > PEG 300 > PEG 400 > DGME, and solubilities in lipophilic vehicles such as PGMC, PGMC, IPM, Captex 200 and Captex 300 were much less than 1.0 mg/ml. Permeation rates through StratTM membrane from pure vehicles were in the rank order: PGMC ${\geq}$ LBF > DMSO ${\geq}$ NMP ${\geq}$ PGML ${\geq}$ PG ${\geq}$ PEG 200 ${\geq}$ DGME ${\geq}$ EtOH. However, permeation rates of TZ through hairless mouse skin from pure vehicles were very low, although PG showed the highest flux ($1.66{\pm}0.28{\mu}g/cm^2{\cdot}hr$). Therefore, PG was selected in further studies. Addition of enhancers (3 v/v%) into PG markedly increased the flux (${\mu}g/cm^2{\cdot}hr$): oleyl alcohol ($14.9{\pm}3.1$) ${\geq}$ oleic acid ($14.5{\pm}1.6$) ${\geq}$ linoleic acid ($13.7{\pm}1.3$) > capric acid ($4.4{\pm}0.6$) > caprylic acid ($2.1{\pm}0.4$). Among hydrophilic vehicles with linoleic acid, PG and DMSO revealed relatively higher permeation for TZ. Increase of donor dose in PG resulted in dose-dependent permeation fluxes. These results suggest that permeation properties of TZ from nonaqueous solutions are markedly different between Strat-$M^{TM}$ membrane and excised hairless mouse skin, and transdermal delivery of TZ would be feasible with a combination of PG and enhancers.