• Journal of Ginseng Research
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• v.44 no.2
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• pp.215-221
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• 2020

Background: Panax ginseng has been used for a variety of medical purposes in eastern countries for more than two thousand years. From the extensive experiences accumulated in its long medication use history and the substantial strong evidence in modern research studies, we know that ginseng has various pharmacological activities, such as antitumor, antidiabetic, antioxidant, and cardiovascular system-protective effects. The active chemical constituents of ginseng, ginsenosides, are rich in structural diversity and exhibit a wide range of biological activities. Methods: Ginsenoside constituents from P. ginseng flower buds were isolated and purified by various chromatographic methods, and their structures were identified by spectroscopic analysis and comparison with the reported data. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H- tetrazolium bromide method was used to test their cytotoxic effects on three human cancer cell lines. Results: Six ginsenosides, namely 6'-malonyl formyl ginsenoside F₁ (1), 3β-acetoxyl ginsenoside F₁ (2), ginsenoside Rh₂₄ (6), ginsenoside Rh₂₅ (7), 7β-hydroxyl ginsenoside Rd (8) and ginsenoside Rh₂₆ (10) were isolated and elucidated as new compounds, together with four known compounds (3-5 and 9). In addition, the cytotoxicity of these isolated compounds was shown as half inhibitory concentration values, a tentative structure-activity relationship was also discussed based on the results of our bioassay. Conclusion: The study of chemical constituents was useful for the quality control of P. ginseng flower buds. The study on antitumor activities showed that new Compound 1 exhibited moderate cytotoxic activities against HL-60, MGC80-3 and Hep-G2 with half inhibitory concentration values of 16.74, 29.51 and 20.48 μM, respectively.

• Archives of Pharmacal Research
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• v.29 no.11
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• pp.998-1005
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• 2006

The effects of imipramine on A-type delayed rectifier $K^{+}$ currents and ATP-sensitive $K^{+}\;(K_{ATP)$ currents were studied in isolated murine proximal colonic myocytes using the whole-cell patch-clamp technique. Depolarizing test pulses between-80 mV and +30 mV with 10 mV increments from the holding potential of-80 mV activated voltage-dependent outward $K^{+}$ currents that peaked within 50 ms followed by slow decreasing sustained currents. Early peak currents were inhibited by the application of 4-aminopyridine, whereas sustained currents were inhibited by the application of TEA. The peak amplitude of A-type delayed rectifier $K^{+}$ currents was reduced by external application of imipramine. The half-inactivation potential and the half-recovery time of A-type delayed rectifier $K^{+}$ currents were not changed by imipramine. With 0.1 mM ATP and 140 mM $K^{+}$ in the pipette and 90 mM $K^{+}$ in the bath solution and a holding potential of -80 mV, pinacidil activated inward currents; this effect was blocked by glibenclamide. Imipramine also inhibited $K_{ATP}$ currents. The inhibitory effects of imipramine in A-type delayed rectifier $K^{+}$ currents and $K_{ATP}$ currents were not changed by guanosine 5-O-(2-thiodiphosphate) ($GDP{\beta}S$) and chelerythrine, a protein kinase C inhibitor. These results suggest that imipramine inhibits A-type delayed rectifier $K^{+}$ currents and $K_{ATP}$ currents in a manner independent of G-protein and protein kinase C.

• Molecules and Cells
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• v.38 no.12
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• pp.1111-1117
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• 2015

Toll-like receptor 5 (TLR5) is a specific receptor for microbial flagellin and is one of the most well-known receptors in the TLR family. We reported previously that TLR5 signaling is well maintained during aging and that caveolin-1 may be involved in TLR5 signaling in aged macrophages through direct interactions. Therefore, it is important to clarify whether caveolin-1/TLR5 interactions affect TLR5 expression during aging. To assess the effect of caveolin-1 on TLR5, we analyzed TLR5 expression in senescent fibroblasts and aged tissues expressing high levels of caveolin-1. As expected, TLR5 mRNA and protein expression was well maintained in senescent fibroblasts and aged tissues, whereas TLR4 mRNA and protein were diminished in those cells and tissues. To determine the mechanism of caveolin-1-dependent TLR5 expression, we examined TLR5 expression in caveolin-1 deficient mice. Interestingly, TLR5 mRNA and protein levels were decreased dramatically in tissues from caveolin-1 knockout mice. Moreover, overexpressed caveolin-1 in vitro enhanced TLR5 mRNA through the MAPK pathway and prolonged TLR5 protein half-life through direct interaction. These results suggest that caveolin-1 may play a crucial role in maintaining of TLR5 by regulating transcription systems and increasing protein half-life.

• The Journal of Korean Society of Virology
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• v.26 no.2
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• pp.227-234
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• 1996

Prostatic carcinoma is the leading second cause of cancer in men. Previous epidermiological studies implicated human papillomavirus as an infectious agent. Since there are only limited studies on the association of HPV to prosate cancer, we examined the prevalence of HPV infections in korean prostate cancer patients. We observed that out of 26 cases, 4 cases and 5 cases were infected by HPV 16(27%) and HPV 18 (31%), respectively and 3 cases by both (46%) and at least 18 were positive for HPV (69%). For these samples, immunohistochemical detection of the p53 and proliferative cell nuclear antigen (PCNA) were also studied, using monoclonal antibodies. Sixteen of 26 (61%) showed immunostaining for p53 protein. While 8 samples with no HPV infection (100%) showed all positive for p53 protein staining, less than half of the 18 patients with any HPV infection (44%) showed p53 protein staining. These findings indicate that altered expression of p53 protein occurs in the more than half of prostate cancers, however, p53 expression is less frequent in HPV infected tissues. This implies that there might be an inverse correlation in general between HPV infection and p53 amplification. However, while 50% (4 of 8) of HPV negative prostate cancer was positive for PCNA staining, 13 out of 18 HPV infected patients (72%) were positive. Therefore HPV infection is more strongly associated with increase proliferation. In addition HPV infected cancer patients are generally in more advanced status implying that HPV infection plays a role in the development of highly malignant prostatic carcinomas, eventhough the statistical significance of this interpretation might be waited for the analysis of more cases.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.629-632
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• 1999

Constructed wetlands are being used for the removal of nutrients from livestock wastewater. However, natural vegetation typically used in constructed wetlands does not have marketable value. As an alternative, agronomic plants grown under flooded or saturated soil conditions that promote denitrification can be used. Studies on constructed wetlands for swine wastewater were conducted in wetland cells that contained either natural wetland plants or a combination of soybeans and rice for two years with the objective of maximum nitrogen reduction to minimize the amount of land required for terminal treatment. Three systems, of two 3.6 by 33.5 m wetland cells connected in series were used; two systems each contained a different combination of emergent wetland vegetation: rush/bulrush (system 1) and bur-reed/cattail (system 2). The third system contained soybean (Glycine max) in saturated-soil-culture (SSC) in the first cell, and flooded rice (Oryza sativa) in the second cell. Nitrogen (N) loading rates of 3 and $10kg\;ha^{-1}\;day^{-1}$ were used in the first and second years, respectively. These loading rates were obtained by mixing swine lagoon liquid with fresh water before it was applied to the wetland. The nutrient removal efficiency was similar in the rush/bulrush, bur-reed/cattails and agronomic plant systems. Mean mass removal of N was 94 % at the loading rate of $3kg\;N\;ha^{-1}\;day^{-1}$ and decreased to 71% at the higher rate of $10kg\;N\;ha^{-1}\;day^{-1}$. The two years means for above-ground dry matter production for rush/bulrushes and bur-reed/cattails was l2 and $33Mg\;ha^{-1}$, respectively. Flooded rice yield was $4.5Mg\;ha^{-1}$ and soybean grown in saturation culture yielded $2.8Mg\;ha^{-1}$. Additionally, the performance of seven soybean cultivars using SSC in constructed wetlands with swine wastewater as the water source was evaluated for two years, The cultivar Young had the highest yield with 4.0 and $2.8Mg\;ha^{-1}$ in each year, This indicated that production of acceptable soybean yields in constructed wetlands seems feasible with SSC using swine lagoon liquid. Two microcosms studies were established to further investigate the management of constructed wetlands. In the first microcosm experiment, the effects of swine lagoon liquid on the growth of wetland plants at half (about 175 mg/l ammonia) and full strength (about 350 mg/l ammonia) was investigated. It was concluded that wetland plants can grow well in at least half strength lagoon liquid. In the second microcosm experiment, sequencing nitrification-wetland treatments was studied. When nitrified lagoon liquid was added in batch applications ($48kg\;N\;ha^{-1}\;day^{-1}$) to wetland microcosms the nitrogen removal rate was four to five times higher than when non-nitrified lagoon liquid was added. Wetland microcosms with plants were more effective than those with bare soil. These results suggest that vegetated wetlands with nitrification pretreatment are viable treatment systems for removal of large quantities of nitrogen from swine lagoon liquid.

• Journal of the Korean Ceramic Society
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• v.42 no.4
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• pp.251-259
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• 2005

In order to characterize the influence of the reaction-site density on the cathodic polarization property of LSCF, we chose the porosity of LSCF as a main controlling variable, which is supposed to be closely related with active sites for the cathode reaction. To control the porosity of cathodes, we changed the mixing ratio of fine and coarse LSCF powders. The porosity and pore perimeter of cathodes were quantitatively analyzed by image analysis. The electrochemical half cell test for the cathodic polarization was performed via 3-probe AC-impedance spectroscopy. According to the investigation, the reduction of oxygen at LSCF cathode was mainly controlled by following two rate determining steps; i) surface diffusion and/or ionic conduction of ionized oxygen through bulk LSCF phase, ii) charge transfer of oxygen ion at cathode/electrolyte interface. Moreover, the overall cathode polarization was diminished as the cathode porosity increased due to the increase of the active reaction sites in cathode layer.

• Journal of Plant Biotechnology
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• v.32 no.1
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• pp.31-35
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• 2005

To obtain regeneration system of onion, we analyzed the effects of 2,4-D and BA concentration on the embryogenic callus induction from mature embryos. The highest embryogenic callus induction ratio was shown on MS medium (Murashie and Skoog 1962) containing $2.5\;\cal{mg/L}\;or\;5\;\cal{mg/L}$ picloram after mature embryos were placed on medium. When induced callus were cultured on half strength of MS medium containing $1\;\cal{mg/L}$ Kinetin, the highest shoot formation ratio was observed on MS medium containing $1\;{mg/L}$ 2,4-D and $1\;{mg/L}$ BA. Embryogenic callus were cultured in MS liquid medium containing $1\;\ccal{mg/L}$ of 2,4-D and $1\;\cal{mg/L}$ BA. The suspension cultured cell clumps could be mass propagated. Embryogenic callus were friable, but non-embryogenic callus included a lot of moisture, hence the identification between embryogenic and non-embryogenic callus as easily achieved. When embryogenic callus as cultured on half strength of MS medium containing $1\;\cal{mg/L}$ Kinetin, shoots were induced. The whole plantlet was obtained on rooting medium containing $0.5\;\cal{mg/}$ of NAA.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.559-564
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• 2015

Background: The participation of women in cervical cancer screening in Malaysia is low. Self-sampling might be able to overcome this problem. The aim of this study was to assess the reliability of self-sampling for cervical smear in our country. Materials and Methods: This cross-sectional study was conducted on 258 community dwelling women from urban and rural settings who participated in health campaigns. In order to reduce the sampling bias, half of the study population performed the self-sampling prior to the physician sampling while the other half performed the self-sampling after the physician sampling, randomly. Acquired samples were assessed for cytological changes as well as HPV DNA detection. Results: The mean age of the subjects was $40.4{\pm}11.3years$. The prevalence of abnormal cervical changes was 2.7%. High risk and low risk HPV genotypes were found in 4.0% and 2.7% of the subjects, respectively. A substantial agreement was observed between self-sampling and the physician obtained sampling in cytological diagnosis (k=0.62, 95%CI=0.50, 0.74), micro-organism detection (k=0.77, 95%CI=0.66, 0.88) and detection of hormonal status (k=0.75, 95%CI=0.65, 0.85) as well as detection of high risk (k=0.77, 95%CI=0.4, 0.98) and low risk (K=0.77, 95%CI=0.50, 0.92) HPV. Menopausal state was found to be related with 8.39 times more adequate cell specimens for cytology but 0.13 times less adequate cell specimens for virological assessment. Conclusions: This study revealed that self-sampling has a good agreement with physician sampling in detecting HPV genotypes. Self-sampling can serve as a tool in HPV screening while it may be useful in detecting cytological abnormalities in Malaysia.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.53-53
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• 1999

전계방출을 이용한 평판 표시장치는 CRT가 가진 장점을 모두 갖는 동시에 얇고 가벼우며 낮은 전력소모로 완벽한 색을 구현할 수 있는 차세대 표시장치로서 이에 대한 여국가 활발히 이루어지고 있다. 여기에 사용되는 음극물질로서 실리콘이나 몰리 등을 팁모양으로 제작하여 사용해 왔다. 하지만 잔류가스에 의한 역스퍼터링이나 화학적 반응에 의해서 전계방출 성능이 점차 저하되는 등의 해결해야할 많은 문제가 있다. 이러한 문제들을 해결하기 위하여 탄소계 재료로서 다이아몬드, 다이아몬드상 카본 등을 이용하려는 노력이 진행되어 왔다. 이중 유리화 비정형 탄소는 다량의 결함을 가지고 있는 유리질의 고상 탄소 재로로서, 전기전도도가 우수하면서 outgassing이 적고 기계적 강도가 뛰어나며 고온에서도 화학적으로 안정하여 전계방출 소자의 음극재료로서 알맞은 것으로 생각된다. 유리화 비정형 탄소가루를 전기영동법으로 기판에 코팅하여 전계방출 소자를 제작하였다. 전기영동 용액으로 이소프로필알코올에 질산마그네슘과 소량의 증류수, 유리화 비정형 탄소분말을 섞어주었고 기판으로는 몰리(Mo)가 증착된 유리를 사용하였다. 균일한 증착을 위해서 증착후 역전압을 걸어 주는 방법과 증착 후 플라즈마 처리를 하는 등의 여러 가지 방법을 사용했다. 전계방출 전류는 1$\times$10-7Torr이사에서 측정하였다. 1회 제작된 용액으로 반복해서 증착한 횟수에 따라 표면의 거치기, 입자의 분포, 전계방출 측정 결과 등의 차이가 관찰되었다. 발광이미지는 전압에 따라 변화하였고, 균일한 발광을 관찰하기 위해서 오랜 시간동안 aging 과정을 거쳐야 했다. 그리고 구 모양의 양극을 사용해서 위치를 변화시키며 시동 전기장을 관찰하여 위치에 따른 전계방출의 차이를 조사하여 발광의 균일성을 알 수 있었다.on microscopy로 분석하였으며 구조 분석은 X-선 회절분석, X-ray photoelectron spectroscopy 그리고Auger electron spectroscope로 하였다. 증착된 산화바나듐 박막의 전기화학적 특성을 분석하기 위하여 리튬 메탈을 anode로 하고 EC:DMC=1:1, 1M LiPF6 액체 전해질을 사용한 Half-Cell를 구성하여 200회 이상의 정전류 충 방전 시험을 행하였다. Half-Cell test 결과 박막의 결정성과 표면상태에 따라 매우 다른 전지 특성을 나타내었다.도상승율을 갖는 경우가 다른 베이킹 시나리오 모델에 비해 효과적이라 생각되며 초대 필요 공급열량은 200kW 정도로 산출되었다. 실질적인 수치를 얻기 위해 보다 고차원 모델로의 해석이 필요하리라 생각된다. 끝으로 장기적인 관점에서 KSTAR 장치의 베이킹 계획도 살펴본다.습파라미터와 더불어, 본 연구에서 새롭게 제시된 주기분할층의 파라미터들이 모형의 학습성과를 높이기 위해 함께 고려된다. 한편, 이러한 학습과정에서 추가적으로 고려해야 할 파라미터 갯수가 증가함에 따라서, 본 모델의 학습성과가 local minimum에 빠지는 문제점이 발생될 수 있다. 즉, 웨이블릿분석과 인공신경망모형을 모두 전역적으로 최적화시켜야 하는 문제가 발생한다. 본 연구에서는 이 문제를 해결하기 위해서, 최근 local minimum의 가능성을 최소화하여 전역적인 학습성과를 높여 주는 인공지능기법으로서 유전자알고리즘기법을 본 연구이 통합모델에 반영하였다. 이에 대한 실증사례 분석결과는 일일 환율예측문제를 적용하였을 경우, 기존의 방법론보다 더 나운 예측성과를 타나내었다.pective" to workflow architectural discussions. The vocabulary suggested

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.50-50
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• 1999

마이크로 공정을 이용한 초소형 정밀 기계는 공정 기술과 재료 기술의 발전에 의하여 더욱 소형화되고 있으며 특히 기능을 갖는 부분과 이 부분을 제어하는 주변회로의 on-chip화의 요구가 증가되기 시작하였다. 이와 같은 추세에 있어서의 문제점은 초소형 정밀기계 부품 소자의 구동을 위한 에너지원의 개발이다. 즉, 소자의 크기가 작아진 것에 부합되는 초소형의 전지가 필요하게 된 것이다. 따라서 보다 완전한 초소형 정밀 기계 및 마이크로 소자의 구현을 위하여 마이크로 소자와 혼성 (Hybrid) 되어 이용될 수 있는 고성능 및 초소형의 전지의 개발이 필수적이다. 초소형 전지의 구현을 위하여 Li계의 2차 전지를 선택하여 이를 박막화하고 반도체 공정을 도입할 수 있다. 이러한 전지를 박막형 2차 전지 또는 박막형 마이크로 전지(thin film Secondary Battery : TFSB or Thin Film Micro-Battery : TFMB)라 하며 이러한 2차 전지는 일반적인 벌크 전지와 동일하게 cathode/Electolyte/Anode의 구조를 갖는다. 박막의 특성상 전해질은 고상의 물질을 사용하는 것이 벌크형 2차 전지와 다른 점이다. TFSB의 성능은 주로 cathode에 의하여 결정되며 지금까지 많은 cathode 물질에 대한 연구 보고가 발표되고 있다. 반도체 공정을 이용한 TFMB의 제작시 무엇보다 중요한 점은 우수한 고상 전해질 및 anode 물질의 선택에 있다. 최근에 2차 전지를 위한 carbon계 anode를 대체할 수 있는 SnO에 대한 보고가 있는데 이는 한 개의 Sn 원자당 2개 이사의 Li가 반응하여 높은 용량을 갖는 전지의 제작이 가능하기 때문이다. Sno2의 anode는 매우 높은 충전용량을 갖는데 첫 번째 방전시에 Li2O를 생성하여 비가역적 반응을 나타내고 계속되는 충방전 동안 Li-Sn 합금이 생성되어 2차전지의 가역적 반응을 가능하게 한다. SnO2 는 대기중에서 Li 금속보다 안정하기 때문에 전지의 제작 공정 및 사용 면에서 매우 우수한 물질이지만 아직까지 SnO2 구조적 특성과 전지의 충, 방전 특성에 대한 관계의 규명을 위한 정확한 정설은 제시되고 있지 못하다. 본 연구에서는 TFSB anode 물질로써 SnOx박막을 상온에서 여러 전도성 콜렉터 위에 증착하여 그 충, 방전 특성을 보고하였다. 증착된 SnOx박막의 표면은 SEM, AFM으로 분석하였으며 구조의 분석은 XR와 Auger electron spectroscope로 하였다. 충, 방전 특성을 분석하기 위하여 리늄 foil을 대극과 참조 전극으로 하여 EC:DMC=1:1, 1M LiPF6 액체 전해질을 사용한 Half-Cell를 구성하여 100회 이상의 정전류 충, 방전 시험을 행하였다. Half-Cell test 결과 박막의 구조, 콜렉터의 종류 및 Sn/O비에 따라 서로 다른 충, 방전 거동을 나타내었다.