• International Journal of Naval Architecture and Ocean Engineering
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• v.2 no.1
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• pp.24-33
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• 2010

Design of a Pump Jet Propulsor (PJP) was undertaken for an underwater body with axisymmetric configuration using axial/low compressor design techniques supported by Computational Fluid Dynamics (CFD) analysis for performance prediction. Experimental evaluation of the PJP was earned out through experiments in a Wind Tunnel Facility (WTF) using momentum defect principle for propulsive performance prior to proceeding with extensive experimental evaluation in towing tank and cavitation tunnel. Experiments were particularly conducted with respect to Self Propulsion Point (SPP), residual torque and thrust characteristics over a range of vehicle advance ratio in order to ascertain whether sufficient thrust is developed at the design condition with least possible imbalance torque left out due to residual swirl in the slip stream. Pumpjet and body models were developed for the propulsion tests using Aluminum alloy forged material. Tests were conducted from 0 m/s to 30 m/s at four rotational speeds of the PJP. SPP was determined confirming the thrust development capability of PJP. Estimation of residual torque was carried out at SPP corresponding to speeds of 15, 20 and 25 m/s to examine the effectiveness of the stator. Estimation of thrust and residual torque was also carried out at wind speeds 0 and 6 m/s for PJP RPMs corresponding to self propulsion tests to study the propulsion characteristics during the launch of the vehicle m water where advance ratios are close to Zero. These results are essential to assess the thrust performance at very low advance ratios to accelerate the body and to control the body during initial stages. This technique has turned out to be very useful and economical method for quick assessment of overall performance of the propulsor and generation of exhaustive fluid dynamic data to validate CFD techniques employed.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1159-1164
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• 2010

Several triterpenoid saponins from root of Pulsatilla koreana Nakai (Ranunculaceae) were studied and their biological activities were reported. It is difficult to analyze triterpenoid saponins using HPLC-UV due to the lack of chromophores. So, evaporative light scattering detection (ELSD) is used as a valuable alternative to UV detection. More recently, a charged aerosol detection (CAD) has been developed to improve the sensitivity and reproducibility of ELSD. In this study, we developed and validated a novel method of high performance liquid chromatography coupled with a charged aerosol detector for the simultaneous determination of four triterpenoid saponins: pulsatilloside E, pulsatilla saponin H, anemoside B4 and cussosaponin C. Analytes were separated by the Supelco Ascentis$^{(R)}$ Express C18 column (4.6 mm ${\times}$ 150 mm, 2.7 ${\mu}m$) with gradient elution of methanol and water at a flow rate of 0.8 mL/min at $30^{\circ}C$. We examined various factors that could affect the sensitivity of the detectors, including various concentrations of additives, the pH of the mobile phase, and the CAD range. Linear calibration curves were obtained within the concentration ranges of 2 - 200 ${\mu}g$/mL for pulsatilloside E, anemoside $B_4$ and cussosaponin C, and 5 - 500 ${\mu}g$/mL for pulsatilla saponin H with correlation coefficient ($R^2$) greater than 0.995. The limit of detection (LOD) and quantification (LOQ) were 0.04 - 0.2 and 2 - 5 ${\mu}g$/mL, respectively. The validity of the developed HPLC-CAD method was confirmed by satisfactory values of linearity, intra- and inter-day accuracy and precision. This method could be successfully applied to quality evaluation, quality control and monitoring of Pulsatilla koreana.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.5
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• pp.905-910
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• 2002

To investigate an eliminatory effect of mixed extract of Hovenia dulcis Thunb, Gastrodia elata and Alnus japonica etc., on the ethanol-induced hangover, 12 hr-fasted male Sprague-Dawley rats weighing 220±20 g were given mixed extract (10 mL/kg, p.o.) and administered ethanol at a dose of 3 g/kg bw (25% in distilled water) orally 30 min postdosing. Blood was collected from caudal artery at 0.25, 0.5, 1, 2, 4, 6, 8, 10, and 12 hr and then the animals were sacrificed at 24 hr after the ethanol treatment. From 0 to 12 hr, the administration of mixed extract significantly decreased the area under the serum alcohol concentrations-vs.-time curves by 21 % compared with control group. In these experiments, liver function indices, such as alanine aminotransferase, aspartate aminotransferase and sorbitol dehydrogenase activities, showed unaltered results in all treated groups compared with the normal group. These results suggest that oral intake of the mixed extract may be effective on elimination of ethanol-induced hangover.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.1
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• pp.91-100
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• 2003

In the present study, we investigated the protective effect of the Lycii Fructus water extracts (LFE) against CCl4-induced hepatotoxicity and the mechanism underlying these protective effects in the rats. The pretreatment of LFE has shown to possess a significant protective effect by lowering the serum alanine and aspartate aminoteansferase (AST and ALT) and alkaline phosphatase (ALP). This hepatoprotective action was confirmed by histological observation, In addition, the pretreatment of LFE prevented the elevation of hepatic malondialdehyde (MDA) formation and the depletion of reduced glutathione (GSH) content and catalase activity in the liver of CC1₄-injected rats. The LFE also displayed hydroxide radical scavenging activity in a dose-dependent manner (IC50 = 83.6 μg/ml), as assayed by electron spin resonance (ESR) spin-trapping technique. Moreover, the expression of cytochrome P450 2E1 (CYP2E1) mRNA, as measured by reverse transcriptase-polymerase chain reaction (RT-PCR), was significantly decreased in the liver of LFE-pretreated rats when compared with that in the liver of control group. Based on these results, it was suggested that the hepatoprotective effects of the LFE may be related to antioxidant effects and regulation of CYP2E1 gene expression.

• Toxicological Research
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• v.13 no.1_2
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• pp.23-27
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• 1997

This study was performed to examine the anti-cancer effect of Red Ginseng in the DENGalN-PH-induced hepatic tumor model system in rats. One hundred of male SPF Sprague-Dawley rats(6weeks old) were randomly divided into five groups. Rats in groups 1, 2, 3, and 4 were administered to diethylnitrosamine intraperitoneally 200 mg/kg body weight for the caner initiation. Rats in group 5 were given to saline as a control. On two weeks after cancer initiation, rats in groups 1 and 3 were fed on diet containing 0.01% of acethylaminofiuorene(AAF) which is strong cancer-promotor for 6 weeks, while rats in groups 2 and 4 were fed on water containing 0.05% of phenobarbital which is weak cancer.promotor for 6 weeks. Rats in groups 1 and 2 were treated with diet containing 3% of Red Ginseng for six weeks(from 9th week till 15th week after cancer initiation). Rats in all groups were necropsied time-sequencially at 8, 15, and 36 weeks. The hepatic lesions of rat treated with carcinogens expressed glutathione S-transferase placental form(GST-P) at 8 week. The GST-P positive foci of rats treated with AAF were larger than that of any other rats, while the GST-P positive foci of rats treated with AAF and red ginseng were significantly decreased. This anti-cancer effect of Red ginseng might be involved in the enhacement of natural killer cell activity. To know whether there is direct relationship between Red Ginseng and natural killer cell activity, the activity of natural killer cell was examined after treatment AAF, AAF+Red ginseng and Red ginseng only, respectively. Comparing with natural killer cell activity in AAF-treated group, natural killer cell activity was significantly activated in AAF+ Red ginseng-treated group. This indicated that Red ginseng might enhance natural killer activity after treatment carcinogen in rats. These results suggested that Red ginseng might have a cancer prevention ability by promoting natural killer cell activity during hepatocarclnogenesis.

• Korean Journal of Environment and Ecology
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• v.21 no.4
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• pp.318-335
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• 2007

Floral study and present vegetation survey were conducted at a representative reclaimed wetland located behind the Rural Research Institute at Ansan, Gyeonggi-do. The importance values were calculated from the ground cover and frequency of recorded species within quadrats and detrended canonical correspondence analysis was conducted using environment variables, such as total nitrogen, electric conductivity, available phosphate, nitrate nitrogen and the distance from the inner roads. And basal areas for the trees encroaching on the reclaimed wetland were estimated to take a look at the on-going situation about the succession routes on land. As a result, 46 families and 158 species of plants were recorded and Pragmites communis was found to be a dominant species as the present vegetation. The ordination analysis results showed that species distribution was purposely explained by total nitrogen in soil and its content in nitrate nitrogen. The invasion of Robinia pseudoacacia and Pinus rigida whose basal areas were $22.3m^2$ and $1.6m^2$ respectively, into the interior areas of the reclaimed wetland was found to cause a disturbance making some parts of the wetland into land. The zoning program using water level control and migratory roads is becoming a contributing factor in destroying a wetland, so it's suggested that some adjustments should be needed to take care of it.

• Journal of Environmental Health Sciences
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• v.33 no.2 s.95
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• pp.137-144
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• 2007

Yam, Prunella was stepwise extracted with hexane, chloroform, ethyl acetate, butanol, and water. Anti-microbial activity of each extract was investigated. Hexane extract was tested for anti-microbial effect on Streptocaccus mutans, one of causative factor of dental caries. Methanol extracts of 7 plants were investigated to anti-microbial effects on S. mutans KCTC 5316, P. gingivalis KCTC 5352, S. aureus KCTC 1927 by means of agar diffusion method. Methanol extract of Yam and Prunella revealed anti-microbial activity against S. mutans, P. gingivalis, and S. aureus. Also, hexane fraction of Yam revealed anti-microbial activity against S. mutans. In sequence of hexane, chloroform, ethylacetate, butanol fraction by Prunelia acted as potent anti-microbial agent on P. gingivalis. The measured MIC of hexane fraction of Yam and Prunella on S. mutans KCTC 5316 strain was 0.25 mg/ml and 0.5 mg/ml and the MIC of hexane fraction of Prunella on S. aureus was 0.5 mg/ml. The hexane fraction of Yam and Prunella suppressed viable ceil counts(VCC) of S. mutans, especially after 24 hrs. The Prunella hexane fraction suppressed VCC of S. aureus, after 12 and 24 hrs. Tested concentrations were 0.1, 0.25 and 0.5 mg/ml. the results were compared with control (0 mg/ml). The pH of S. mutans media and GTase activity were determined to evaluate the anticariogenic activity of Yam, Prunella hexane fraction. The pH were increased from 5.6 to 7.0-7.2 in concentration of 2.0 mg/ml. Yam hexane extraction revealed 35% inhibition to GTase activity and Punella inhibited 25% of GTase. These results suggest that the hexane extracts of Yam and prunella have Antibacterial activities against S. mutans, P. gingivalis, S. aureus and have preventive effect on dental caries.

• The Korean Journal of Physiology
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• v.19 no.1
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• pp.49-59
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• 1985

The effects of anions on net accumulation of $(\rho-aminohippuric\;acid)$(PAH) were studied in rabbit kidney cortical slices. Experiments were carried while varying the major anionic composition of the incubation medium(replacement of $Cl^-$ by isethionate and $SCN^-$). The total replacement of $Cl^-$ with isethionate, $SO_4\;^{2-}$ and $SCN^-$ in the incubation medium decreased the 60-min slice-to-medium concentration(S/M) ratio of PAH to 60%, 40% and 50% of control value, respectively. The degree of inhibition in PAH accumulation by the replacement of isethionate and $SCN^-$ was increased with increasing of both preincubation and incubation time. The influence of isethionate and $SCN^-$ on PAH uptake was fully reversible. Both isethionate and $SCN^-$ increased the apparent Km value significantly with no change on the apparent Vmax value, suggesting a competitive inhibition on PAH uptake. And the inhibitory effect of $SCN^-$ on PAH uptake decreased with increase of pH in the incubation medium while that of isethionate increased with increase of pH. Intracellular water content, intracellular electrolyte concentration and oxygen consumption were not influenced by the replacement of $Cl^-$ with isethionate or $SCN^-$ in the incubation medium. These results suggest that both $isethionate^-$ and $SCN^-$ inhibit the PAH uptake by binding to some site necessary for normal PAH transport without affecting the cellular viability.

• The Korean Journal of Physiology
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• v.19 no.1
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• pp.25-33
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• 1985

Renal arterial infusion of renotropic agents has been a very useful technique in the renal function studies. This type of experiments have usually been conducted in the large animals such as dogs and sheep. In these animals a catheter can be placed in the site without much disturbances of renal blood flow. Rabbits as an experimental model, however, caused a disturbances of renal blood flow by a catheterization of renal artery by its properties. Therefore we have developed a new technique that allows a simple and selective access to one side of renal arteries and the other as a control, without any disturbances of renal function. The distance between the both bifurcations of renal arteries on abdominal aorta is about 7 mm. To locate the tip of catheter on one side renal artery, ascending cannulation performed via femoral artery was done. We did an experiment with the technique to clarify the effect of calmodulin inhibitor on the renal function. One of the phenothiazine derivatives, trifluoperazine known as a powerful calmodulin inhibitor. Trifluoperazine, actual dose ranges of $2.76-5.20\;ug\;{\cdot}\;kg^{-1}\;{\cdot}\;min^{-1}$, increased urine volume and glomerular filtration rate significantly. Significant increases in urinary excretion of sodium, chloride and potassium were found. Fractional excretion of sodium and free water clearance increased significantly. These data suggest that this new technique is very useful in field of renal physiology and that striking effect of trifluoperazine on the renal function may be caused by increasing the renal hemodynamics, and by the inhibition of sodium, chloride and potassium reabsorption in the renal tubules.

• The Journal of Internal Korean Medicine
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• v.33 no.4
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• pp.520-532
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• 2012

Objectives : This study was carried out to investigate the effects of Coicis Semen Extract (CSE) on the experimental colitis induced by dextran sulfate sodium (DSS) in mice. Methods : Experimental colitis was induced by daily treatment with 5% DSS in the drinking water for 7 days in 6-week-old male ICR mice. The colitic mice were divided into three groups: the normal (N) group consisted of mice that were not inflammation-induced. The control (C) group was composed of untreated colitis elicited mice. The sample (S) group was administered CSE after colitis elicitation. The effects on colonic mucosal ulcers were evaluated by the morphological, histological and immunohistochemical change of the large intestine. Results : Inhibition of LPS-induced NO decreased in the S group. Inhibition of LPS-induced iNOS and COX-2 mRNA noticeably decreased in the S group from 0.25 mg/ml. In the common morphological and histochemical change, the erosion and the infiltration of inflammatory cells increased in the C group, while they noticeably decreased in the S group. The length of colon was shortened more in the C group than in the S group. The distributions of MUC2 and Hsp70 treated with CSE increased noticeably more in the S group than in the C group (p<0.05). It was confirmed histochemically and immunohistochemically that the distributions of iNOS, COX-2, MAC387, serotonin, apoptosis and PCNA treated with CSE decreased in the S group more than in the C group (p<0.05). Conclusions : It is confirmed that CSE has cytoprotective effect, so can alleviate inflammation process. Therefore, it is expected to have potential protective effect on colitis.