• Journal of Communications and Networks
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• 제8권3호
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• pp.290-296
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• 2006

In this paper, a generalized blind adaptive algorithm is introduced for multi-user detection of direct sequence code division multiple access (OS-COMA) wireless communication systems. The main property of the proposed algorithm is its ability to resolve the multipath fading channel resulting in inter symbol interference (ISI) as well as multiple access interference (MAI). Other remarkable properties are its low complexity and mitigation to the near-far problem as well as its insensitivity to asynchronous transmission. The proposed system is based on the minimization of the output energy and convergence to the minimum mean square error (MMSE) detector. It is blind in the sense that it needs no knowledge of the other users' signatures, only the intended user signature and timing are required. Furthermore, the convergence of the minimum output energy (MOE) detector to the MMSE detector is analytically proven in case of M-ary PSK. Depicted results show that the performance of the generalized system dominates those previously considered. Further improvements are obtained when multiple input multiple output (MIMO) technique is employed.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.380.2-380.2
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• 2002

Peroxisome proliferator-activated receptor (PPAR)-$\gamma$ is a nuclear hormone receptor family that plays an important role in the transcriptional regulation of genes in cellular lipid and energy metabolism. In our search for Iigands for PPAR-$\gamma$ from natural resources. two phenylpropanoids. 3.4.5-Trimethoxy cinnamylalcohol (1) and 3.4.5- Trimethoxy cinnamaldehyde (2). were isolated as PPAR-$\gamma$ agonists from the MeOH extracts of Zanthoxylum schinifolium Sieb. & ZUCCo (Rutaceae) by activity-guided fractionation. These two compoundS bind and activated PPAR-$\gamma$ transcriptional activity in a dose dependent manner assessed by ligand-binding assay. While the maximum activities for PPAR-$\gamma$ of these compounds were comparable with that of rosiglitazone. which is currently used in the treatment of Type II diabetes. the potency of these compounds were much weaker than rosiglitazone ($ED_{50}$=t.2$\mu\textrm{M}$) with the $ED_{50}$ values of 9.08 and 4.08 $\mu\textrm{M}$. respectively. To examine the structure-activity relationship of phenylpropanoids. we prepared several phenylpropanoid derivatives and measured the activity. We observed that substituents at 4'- position could playa key role in determining the potency for PPAR-$\gamma$ agonistic activity .

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.223.2-223.2
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• 2003

A rapid, sensitive and selective liquid chromatography-tandem mass spectrometric (LC/MS/MS) method for the determination of eupatilin in human plasma was developed. Eupatilin and internal standard, (S)-[N-3-(4-(2-(1-methyl-5-tetrazolyl)-pyridine-5-y1)- 3-fluorophenyl)-2-oxo-5-oxazolidinyl]methyl acetamide (DA-7867) were extracted from human plasma by liquid-liquid extraction and analyzed on a phenyl-hexyl column with the mobile phase of acetonitrile-ammonium formate (10 mM, pH 3.0) (60:40, v/v). (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.306.1-306.1
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• 2002

Cefodizime has originally been developed for treating infections as antibiotics. However. according to some of recent studies. cefodizime. a third generation cephalosporin. may potentially have the capability of stimulating chemotactic activity of neutrophils and monocytes as well as the strong immuno-modulator. In this study. we studied to learn about the expressive effect of dentritic cells and macrophage. With this background. We have studied to see if cefodizime can be a potential substance inducing an immunological function in dendritic cells and peritoneal macrophages. IL-12 activates NK cell and macrophage, and shows antiviral effect by excreting INF-${\gamma}$. In vitro. total RNAs were extracted from murine dentritic cell at 4, 8, 12, 24hr after the application of 10, 50, 100${\gamma}g$/ml of cefodizime wighout other stimulators. And we analyzed IL-12 mRNA using RT-PCR method. In conclusion. IL-12 mRNA was increased. and the results suggest that cefodizime activate TH1 cell induction, CTL differentiation as well as accelerating the increase of NK. LAK cell.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.202.4-203
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• 2003

The present study was carried out to clarify whether isoflavonoids isolated from Belamcandae Rhizoma (Iridaceae) inhibit inflammation and angiogenesis by the experimental methods in vitro and in vivo. Among the isolated isoflavonoids, such as irigenin, irisflorentine, and iristectorene B inhibited nitric oxide (NO) production, as measured by nitrite formation at 3-30 ${\mu}M$. Also these compounds reduced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) enzyme expression in a concentration dependent manner, when measured by western blotting, at 3-30 ${\mu}M$. Irigenin, irisflorentine and iristectoren B decreased angiogenesis of chick embryos in the chorioallantoic membrane assay. These compounds also reduced the proliferation of calf pulmonary arterial endothelial (CPAE) cells and found to possess relatively weak gelatinase/collagenase inhibitory activity in vitro. These compounds, when administered subcataneously at the dose of 30mg/kg for 20 days to mice implanted with murine Lewis lung carcinoma (LLC), caused a significant inhibition of tumor volume. Therefore, antiangiogenic activities of isoflavonoids from Belamcandae Rhizoma might be due to antiproliferative activities under inhibition the induction of COX-2 and iNOS enzyme.

• 정보처리학회논문지C
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• 제11C권1호
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• pp.141-148
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• 2004

최근 초고속 인터넷, HDTV, 3차원 입체 고 선명 TV, 그리고 ATM backbone 망 등과 같은 광대역 통신의 요구가 빠른 속도로 증가하고 있다. 따라서 무선망을 통한 광대역 데이터를 전송하기 위해 Ka 대역 주파수의 사용이 요구된다. 그런데 Ka 대역 주파수를 사용하면 강우에 의한 페이딩이나 대기손실에 의해 수신 데이터의 성능이 심각하게 영향을 받는다. 따라서 채널환경에 의한 성능 감소를 극복하기 위해 적응형 모뎀이 요구된다. 본 논문에서는 채널환경을 극복하는 155Mbps급 적응형 모뎀의 구조를 제시하고 설계한다. Ka 대역의 무선통신 채널에 대한 강우감쇠를 보상하기 위해 다양한 부호 율을 갖는 적응형 부호화 기법 및 TC-8PSK, QPSK, BPSK와 같은 다중 변조기법을 채택한다. 또한 본 논문에서는 다중 복조기에서 변조방식의 정보 없이 복조하기 위한 블라인드 복조방법을 제안하고, 빠른 위상모호성 해결 방법을 제안하며, SPW모델에 의해 적응형 모뎀의 설계와 시뮬레이션 결과를 제시한다. 본 155Mbps급 적응형 Modem은 $0.25\mu{m}$ CMOS 표준 셀 기술과 95만 게이트로 설계하고 구현하였다.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.312.3-313
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• 2002

Recently we have reported that various hydroxystilbenes show strong inhibition of human P450 1 activity. A series of synthetic trans-stilbene derivatives were prepared and their inhibitory potentials were evaluated with the bacterial membrane of recombinant human P450 1A1, 1A2 or 1B1 coexpressed with human NADPH-P450 reductase to find new candidates for cancer chemoprevention, Of the compounds tested. SY-021 (3.5-dimethoxyphenyl vinyl thiophene) exhibited a potent inhibition of human P450 181 with an IC$_{50}$ value of 2 nM. SY-021 also showed the inhibitrion of P450 1A1 with IC$_{50}$ value of 61 nM and P450 1A2 with IC$_{50}$ value of 11 nM. SY-021 showed 31-fold selectivity for P450 1B1 over P450 1A1 and 6-fold selectivity for P450 1B1 over 1A2. We have further investigated the inhibition kinetics of P450 1A1. 1A2 and 1B1 by SY-021. The modes of inhibition by SY-021were non-compeitive for all three P450 1 enzymes. Effect of preincubation with NADPH on inhibition of P450 1B1 by SY-021 was determined. These results suggest that SY-021 is one of the mostj potent inhibitor of human P450 1 enzymes and may be considered as a good candidate for a cancer chemopreventive agent in human

• 약학회지
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• 제59권4호
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• pp.164-169
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• 2015

In the present study, we determined the effect of $18{\beta}$-glycyrrhetinic acid ($18{\beta}$-GA) in the mice model bearing xenografts of HT-29 human colon cancer cell line. Data from the cytotoxicity assay displayed that $18{\beta}$-GA induced cell death in HT-29. The cytotoxicity was enhanced as the $18{\beta}$-GA treatment was prolonged. In case of 72 hrs treatment, $LD_{50}$ of $18{\beta}$-GA was approximately $90{\mu}M$, and the efficacy at $100{\mu}M$ of $18{\beta}$-GA appeared to be equivalent to that of doxorubicin at $1{\mu}M$. Based on the in vitro data, we tested the anti-tumor effect of $18{\beta}$-GA in thymic mice (Balb/c strain). Xenograft tumors were generated by subcutaneous injection of HT-29 ($3{\times}10^6cells/mouse$) to mice and the mice were treated intraperitoneally with $18{\beta}$-GA ($50{\mu}g/time/mouse$) every other day for 4 times. The tumor volumes were measured for a period of 14 days. Data displayed that the $18{\beta}$-GA treatment reduced the tumor volumes (P < 0.05) as compared to control mice. However, this activity was demolished when athymic mice (Balb/c nu/nu) were used instead of thymic mice. This observation appeared that T lymphocyte played an important role in the anti-tumor activity. In conclusion, our results indicate that $18{\beta}$-GA has anti-tumor activity in HT-29 tumor-bearing mice, which may be associated with T cells.

• 한국통신학회논문지
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• 제31권9C호
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• pp.831-839
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• 2006

본 논문에서는 수신기에서 I/Q 위상 및 진폭 불균형을 갖는 계층적 MPSK(Hierarchical M-ary Phase Shift Keying) 신호에 대해 수치 적분이 필요 없는 정확하고 일반화된 closed-form 형태의 비트 오류 확률(Bit Error Probability) 표현을 유도한다. 새롭게 유도된 비트 오류 확률 표현은 간결한 형태의 일반화된 식으로 되어 있어 다양한 환경으로의 적용이 용이하다. 뿐만 아니라, 계층적 MPSK를 적용하는 많은 디지털 통신 시스템에서 복조시 발생할 수 있는 I/Q 불균형들에 의한 시스템 성능 변화에 대하여 정확한 이론적 성능 기준을 제공할 것으로 기대된다.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.377.3-378
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• 2002

Eight compounds were isolated from the MeOH extracts of Erythrina senegalensis for HIV-1 protease inhibitors. Their structures were elucidated as eight isoflavonoids by spectroscopic analysis. These compounds showed dose dependent inhibitory activities on HIV-l protease with $IC_{50}$ values from 0.5 to 30.0 ${\mu}$M. (omitted)