• Natural Product Sciences
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• v.22 no.2
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• pp.93-101
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• 2016

For efficient quality control of the Samryeongbaekchul-san decoction, a powerful and accurate an ultra-performance liquid chromatography (UPLC) coupled with electrospray ionization (ESI) tandem mass spectrometry (MS) method was developed for quantitative analysis of the thirteen constituents: allantoin (1), spinosin (2), liquiritin (3), ginsenoside Rg1 (4), liquiritigenin (5), platycodin D2 (6), platycodin D (7), ginsenoside Rb1 (8), glycyrrhizin (9), 6-gingerol (10), atractylenolide III (11), atractylenolide II (12), and atractylenolide I (13). Separation of the compounds 1 - 13 was performed on a UPLC BEH $C_{18}$ column ($2.1{\times}100mm$, $1.7{\mu}m$) at a column temperature of $40^{\circ}C$ with a gradient solvent system of 0.1% (v/v) formic acid aqueous-acetonitrile. The flow rate and injection volume were 0.3 mL/min and $2.0{\mu}L$. Calibration curves of all compounds were showed good linearity with values of the correlation coefficient ${\geq}0.9920$ within the test ranges. The values of limits of detection and quantification for all analytes were 0.04 - 4.53 ng/mL and 0.13 - 13.60 ng/mL. The result of an experiment, compounds 2, 6, 12, and 13 were not detected while compounds 1, 3 - 5, and 7 - 11 were detected with 1,570.42, 5,239.85, 299.35, 318.88, 562.27, 340.87, 12,253.69, 73.80, and $115.01{\mu}g/g$, respectively.

• Natural Product Sciences
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• v.13 no.4
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• pp.378-383
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• 2007

Phenathrene derivatives, such as batatasins, are well-known constituents in Dioscorea Rhizoma. Although phenanthrenes have been reported as representative compounds in this plant, standard markers for quality control have been focused on the polar constituents (saponins and purine derivatives). Herein, simple, rapid and reliable HPLC method was developed to determine 3,5-dimethoxyphenanthrene-2,7-diol (DMP) and batatasin-I (BA-I) as non-polar standard maker compounds of Dioscorea Rhizoma. DMP and BA-I were analyzed under optimized HPLC conditions [column: Columbus $5{\mu}$ C18 100A ($30{\times}4.6mm$ i.d., $5{\mu}m$; mobile phase: $H_2O$ with 0.025% $CH_3COOH$ (v/v) for solvent A and $CH_3CN$ with 0.025% $CH_3COOH$ (v/v) for solvent B, gradient elution; flow rate: 2 mL/min; detection: 260 nm), and each experiment was finished within 13 min. Good linearity was achieved in the range from 0.5 to $10.0{\mu}g/mL$ for each compound, and intra- and inter-day precision were in the acceptable levels. The recovery test were performed with three different Dioscorea Rhizoma samples (D. opposita, D. batatas and D. japonica), and showed its accuracy values in the range of 97.2 - 102.8% for three different concentrations of DMP and BA-I. The content levels of DMP and BA-I were ranged under 0.0020%. These results demonstrated that amounts of DMP and BA-I are easily determined with conventional HPLC-UV-DAD method although the content levels were lower than those of saponins and allantoin in Dioscorea Rhizoma. This HPLC method could be used for quality control of various Dioscorea preparations.

• Journal of Chest Surgery
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• v.18 no.4
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• pp.718-731
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• 1985

Renal dysfunction is a common complication of open-heart surgery: a form of controlled hemorrhagic shock, and successful perioperative management of renal dysfunction depends on recognition of the risk factors and optimal management of factors influencing renal function, including cardiopulmonary bypass, and early detection of renal failure. Changes in renal functional parameters including Ccr, Cosm, CH2O, FENa, and RFI were observed prospectively in forty five patients operated on at Dept. of Thoracic and Cardiovascular Surgery, S.N.U.H., from April to June, 1985. They were 23 males and 22 females with 35 acquired and 10 congenital heart diseases and the mean age and body surface area of them were 38.010.3 years [22-63] and 1.5518 M2[1.151.92] respectively. Followings are the conclusion. 1. The Ccr, representative of renal function, is significantly improved from 90.231.3 ml/min/M2 preoperatively to 101.536.4 ml/min/M2 postoperative and day [P<0.05], and all patients were classified as postoperative renal functional class I of Abel, which representing adequate renal protection during our cardiopulmonary bypass. 2. The Cosm is significantly elevated at immediate postperfusion time and remained high at postoperative one day representing osmotic diuresis at that time, but CH2O shows no significant changes at immediate postperfusion period and is decreased significantly at postoperative one day, representing recovery of renal concentrating ability at that time with decreasing urine flow. 3. The absolute value and changing tendency in FENa and RFI during perioperative period shows no diagnostic reliability on these parameters, but those of CH2O appear to reveal future renal function more accurately than Ccr 4. The depth of hypothermia may be protective upon renal function against the ill effects of prolonged nonpulsatile cardiopulmonary bypass. 5. The depth of the hypothermia, pump time of more than 150 minutes, poor cardiac function, and intraoperative events such as embolism appear to be related with immediate postperfusion renal function. 6. Hemoglobinuria and hemolysis, poor preoperative renal function, history of cardiac surgery, and massive transfusion associated with bleeding appear not to be related with renal dysfunction.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.186-186
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• 2013

종래의 흑연 위주 연료전지 분리판 개발되어 최근 고분자 전해질 막 연료전지가 높은 전력, 낮은 배기 가스 배출, 낮은 작동 온도로 자동차 산업에서 상당한 주목을 받고 있다. 요구사항은 높은 전기 전도도, 높은 내식성, 낮은 가스 투과성, 낮은 무게, 쉬운 가공, 낮은 제조비용이다. Thin film Cr 장비로 저항가열 furnace, sputter 등이 사용된다. 연료전지 분리판의 고전도도, 내부식성 보호막의 고속 증착을 위한 새로운 증착원으로 스퍼터 - 승화형 소스의 가능성을 유도 결합 플라즈마에 금속 봉을 직류 바이어스 함으로써 시도하였다. 유도 결합 플라즈마를 이용하여 승화증착 시스템을 사용하여 OES (SQ-2000)와 QMS (CPM-300)를 사용하여 $N_2$ flow에 따른 유도 결합 플라즈마를 이용한 스퍼터-승화증착 시스템을 사용 하여도 균일한 공정을 하는 것을 확인 하였다. 5 mTorr의 Ar 유도 결합 플라즈마를 2.4 MHz, 500 W로 유지하면서 직류 바이어스 전력을 30 W (900 V, 0.02 A) 인가하고, $N_2$의 유량을 0.5, 1.0, 1.5 SCCM로 변화를 주어 특성을 분석하였다. MID (Multiple Ion Detection) mode에서 유도결합 플라즈마를 이용한 스퍼터-승화 증착 장비를 사용하여 CrN thin flim 성장시켰고, deposition rate은 44.8 nm/min으로 얻을 수 있었다. 또한 $N_2$의 유량이 증가할 수록 bias voltage가 증가하는 것을 확인 할 수 있었다. OES time acquisition을 이용한 공정 분석에서는 $N_2$ 유량을 off 하였을 때 Ar, Cr의 중성 intensity peak이 상승하였고, 시간 경과에 따라 sublimation에 의한 영향이 없는 것을 확인 할 수가 있었다. XRD data에서는 질소 유량이 증가함에 따라 $Cr_2N$이 감소하고, CrN이 증가하는 것을 확인할 수가 있었다. 결정배향성과 Morphology는 다결정 재료의 경도에 영향을 주는 인자이다. CrN 결정 구조의 경우는 (200)면이 경도가 제일 높은데 (200)면에서 성장한 것을 확인 할 수 있었다. 잔류가스 분석 결과로는 일정한 Ar의 유량을 흘렸을 때 $N_2$의 변화량이 비례적인 경향이 보이는 것을 확인 할수 있었다. 또한 $N_2$가 흐르면서도 유도 결합 플라즈마를 이용한 스퍼터-승화 증착 시스템을 사용하면 일정한 공정을 하는 것을 확인 할 수 있었다. 질소의 분압이 유량에 따라서 $3.0{\times}10^{-10}$ Torr에서 $1.65{\times}10^{-9} $Torr까지 일정한 비율로 증가한다. 즉, 이 시스템으로 양산장비 설계를 하여도 가능 하다는 것을 말해준다.

• Parasites, Hosts and Diseases
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• v.58 no.2
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• pp.173-179
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• 2020

Leishmaniasis is a prevalent cause of death and animal morbidity in underdeveloped countries of endemic area. However, there is few vaccine and effective drugs. Antimicrobial peptides are involved in the innate immune response in many organisms and are being developed as novel drugs against parasitic infections. In the present study, we synthesized a 5-amino acid peptide REDLK, which mutated the C-terminus of Pseudomonas exotoxin, to identify its effect on the Leishmania tarentolae. Promastigotes were incubated with different concentration of REDLK peptide, and the viability of parasite was assessed using MTT and Trypan blue dye. Morphologic damage of Leishmania was analyzed by light and electron microscopy. Cellular apoptosis was observed using the annexin V-FITC/PI apoptosis detection kit, mitochondrial membrane potential assay kit and flow cytometry. Our results showed that Leishmania tarentolae was susceptible to REDLK in a dose-dependent manner, disrupt the surface membrane integrity and caused parasite apoptosis. In our study, we demonstrated the leishmanicidal activity of an antimicrobial peptide REDLK from Pseudomonas aeruginosa against Leishmania tarentolae in vitro and present a foundation for further research of anti-leishmanial drugs.

• The Korean Journal of Nuclear Medicine
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• v.21 no.2
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• pp.155-165
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• 1987

The noninvasive nature of the radionuclide angiocardiography provided a useful approach for the evaluation of left-to-right cardiac shunts (LRCS). While the qualitative information can be obtained by inspection of serial radionuclide angiocardiograms, the quantitative information of radionuclide angiocardiography can be obtained by the analysis-of time-activity curves using advanced computer system. The count ratios method and pulmonary-to-systemic flow ratio (QP/QS) by gamma variate fit method were used to evaluate the accuracy of detection and localization of LRCS. One hundred and ten time-activity curves were analyzed. There were 46 LRCS (atrial septal defects 11, ventricular septal defects 22, patent ductus arteriosus 13) and 64 normal subjects. By computer analysis of time-activity curves of the right atrium, ventricle and the lungs separately, the count ratios modified by adding the mean cardiac transit time were calculated in each anatomic site. In normal subjects the mean count ratios in the right atrium, ventricle and lungs were 0.24 on average. In atrial septal defects, the count ratios were high in the right atrium, ventricle and lungs, whereas in ventricular septal defects the count ratios were higher only in the right ventricle and lungs. Patent ductus arteriosus showed normal count ratios in the heart but high count ratios were obtained in the lungs. Thus, this count ratios method could be separated normal from those with intra cardiac or extracardiac shunts, and moreover, with this method the localization of the shunt level was possible in LRCS. Another method that could differentiate the intracardiac shunts from extracardiac shunts was measuring QP/QS in the left and right lungs. In patent ductus arteriosus, the left lung QP/QS was higher than those of the right lung, whereas in atrial septal defects and ventricular septal defects QP/QS ratios were equal in both lungs. From this study, it was found that by measuring QP/QS separately in the lungs, intracardiac shunt could be differenciated from extracardiac shunts.

• Nutrition Research and Practice
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• v.7 no.4
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• pp.249-255
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• 2013

In this study, the protective effects of EGCG on L-3,4-dihydroxyphenylalanine (L-DOPA)-induced oxidative cell death in catecholaminergic PC12 cells, the in vitro model of Parkinson's disease, were investigated. Treatment with L-DOPA at concentrations higher than $150{\mu}M$ caused cytotoxicity in PC12 cells, as determined using the 3-(4,5-dimetylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry detection. The apoptotic ratio was similar in cells treated with $100{\mu}M$ EGCG plus $150{\mu}M$ L-DOPA (5.02%) and the control (0.96%) (P > 0.05), and was lower than that of cells treated with L-DOPA only (32.24%, P < 0.05). The generation level of ROS (% of control) in cells treated with EGCG plus L-DOPA was lower than that in cells treated with L-DOPA only (123.90% vs 272.32%, P < 0.05). The optical density in production of TBARS in cells treated with L-DOPA only was higher than that in the control ($0.27{\pm}0.05$ vs $0.08{\pm}0.04$, P < 0.05), and in cells treated with EGCG only ($0.14{\pm}0.02$, P < 0.05), and EGCG plus L-DOPA ($0.13{\pm}0.02$, P < 0.05). The intracellular level of GSH in cells treated with EGCG plus L-DOPA was higher than that in cells treated with L-DOPA only ($233.25{\pm}16.44$ vs $119.23{\pm}10.25$, P < 0.05). These results suggest that EGCG protects against L-DOPA-induced oxidative apoptosis in PC12 cells, and might be a potent neuroprotective agent.

• KIPS Transactions on Computer and Communication Systems
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• v.3 no.11
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• pp.427-432
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• 2014

The Purpose of local system attacks is to acquire administrator's(root) privilege shell through the execution of the malicious program or change the flow of the program. This acquiring shell through attack is still valid approach method and it is difficult to cope with improving each of vulnerability because the attacker can select various forms of attack. Linux allocate a set of credentials when login, in order to manage user permissions. Credentials were issued and managed by the kernel directly, and also the kernel ensures that any change cannot be occurred outside of kernel. But, user's credentials that acquired root privilege through system attacks occurs a phenomenon that does not remain consistent. In this paper we propose a security module to detect a security threats that may cause to users and tasks by analysis user task execution and inconsistency credentials.

• Korean Journal of Remote Sensing
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• v.20 no.2
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• pp.125-137
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• 2004

In case of using image sequence taken from a moving camera along a road in an urban area, general video mosaicing technique based on a single baseline cannot create 2-D image mosaics. To solve the drawback, this paper proposed a new image mosaicing technique through 3-D multi-baselines that can create image mosaics in 3-D space. The core of the proposed method is that each image frame has a dependent baseline, an equation of first order, calculated by using ground control point (GCP) of optical flows. The proposed algorithm consists of 4 steps: calculation of optical flows using hierarchical strategy, calculation of camera exterior orientation, determination of multi-baselines, and seamless image mosaics. This paper realized and showed the proposed algorithm that can create efficient image mosaics in 3-D space from real image sequence.

• Journal of the Korean Society of Propulsion Engineers
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• v.18 no.5
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• pp.62-69
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• 2014

Infrared signature of rocket plume plays an important role for detection, recognition, tracking and minimzing for low observability. Infrared signatures of rocket plume with reduced smoke propellant and smokeless propellant are measured. In order to estimate the infrared signature of rocket plume, CFD analysis for flow structure of plume is performed, and layered integration method for estimating of infrared signature is used. Numerical and experimental results were in good agreement. Both propellants had similar infrared signature. Strong peak at $4.3{\mu}m$ region in the experimental results is appeared due to experimental error arising from the calibration procedure.