• Applied Biological Chemistry
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• v.49 no.4
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• pp.281-286
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• 2006

Tolaasin, a pore-forming toxin, is a 1,985 Da peptide produced by Pseudomonas tolaasii and causes a brown blotch disease on cultivated mushrooms. Tolaasin forms pores on the plasma membrane of various cells including fungi, bacteria, plant as well as erythrocytes, and destroys cell structure. $Zn^{+2}$ has been known to block the tolaasin activity by an unknown mechanism. Thus, we investigated the inhibitory effects of $Zn^{+2}$ on the tolaasin-induced hemolysis to understand the molecular mechanism of tolaasin-induced pore formation. $Zn^{+2}$ and $Cd^{+2}$ inhibited the tolaasin-induced hemolysis in a dose-dependent manner and their Ki values were 170 ${\mu}M$ and 20 mM, respectively. The effect of $Zn^{+2}$ was reversible since the subsequent addition of EDTA chelates $Zn^{+2}$ and removes the inhibitory effect of $Zn^{+2}$. When an osmotic protectant, PEG 2000, was added, the tolaasin-induced hemolysis was not observed. After the removal of osmotic protectant by centrifugation, resuspended erythrocytes with fresh medium were immediately hemolyzed, while the addition of $Zn^{+2}$ prevented from hemolysis, implying that tolaasin-induced pores on the membrane were already formed in the medium containing osmotic protectant. These results suggest that $Zn^{+2}$ inhibits the activity of tolaasin pores and it has minor effects on the membrane binding of tolaasin and the formation of pore.

• Applied Biological Chemistry
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• v.43 no.2
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• pp.141-147
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• 2000

Interrelation between the antioxidative activity of hot-water extracts of 130 medicinal plants and their cellular antimutagenic activity was investigated. Antioxidative activity was evaluated by assaying electron-donation to DPPH free radical and scavenging of hydroxyl radical $({\cdot}OH)$ generated through Fenton rection, respectively. All medicinal plants examined in this study exhibited markedly electron-donating ability and radical scavenging ability in each assay system. The results demonstrated the fact that Pilbal (Piper longum L.) is the strongest in electron-donating activity, on the other hand, that Seokgok (Dendrobium moniliforme L.) is the strongest in ${\cdot}OH$ scavenging activity. When evaluated their antioxidative activities, 24 medicinal plants including Jimo (Anemarrhena asphodeloides Bunge) were found to be the medicinal plants carrying strong antioxidative activity, which exhibited more than 50% activity compared to the control group in both electron-donating and free radical scavenging. The experiment was also performed to examine whether 11 medicinal plants having significant antimutagenicity damage DNA in the presence of $Cu^{2+}$, showing the fact that all samples tested, except Taeksa (Alisma canaliculatum All. Br.), Paekjain (Nitraria sibirica Pall) and Ohyak (Lindera strychifolia Sieb. et Zucc. Villar) are capable of inducing DNA strand break. We also found that Taeksa and Paekjain strongly block DNA strand break induced by chemical mutagen mitomycin C.

• Magazine of the Korean Society of Agricultural Engineers
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• v.27 no.1
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• pp.62-70
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• 1985

The purpose of this study is to investigate the basic data such the total, the daily maximum, and the peak stage of consumptive use of water and also the soil moisture extraction pattern for irrigation plan of tobacco during the growing period. The plots at which this study was conducted are divided into three fertilization levels of 30g, 60g, and 90g. Each block for three levels is divided as vinyl mulching and irrigation plot, vinyl mulching and nonirrigation plot, and nonmulching and irrigation plot. The results obtained are summarized as follows: 1. The evapotranspiration amount of mulching-irrigation plots are similar to that of mulching-nonirrigation plots. While, the evapotranspiration amount of mulching plots are different obviousely from that of nonmulching plots. Therefore, a significance was recognized between the mulching plots and the nonmulching plots. 2. The amount of evapotranspiration in case of 60g and 90g fertilization level was larger than that of 30g. But the 60g plots and the 90g plots showed little differences. 3. In the total amount of evapotranspiration for each of the experimental plots during the growing period, nonmulching-irrigation plot showed the largest value of 332.9mm, second the mulching-irrigation plot, 284. 9mm, and the mulching-nonirrigation plot, the smallest as 255. 9mm. 4. In the monthly average amount of evapotranspiration for each of the treatment plots, the mulching-irrigation the mulching-nonirrigation, and the nonmulching-irrigation plot showed 3. 6mm, 3. 2mm and 4. 2mm respectively. The daily maximum amount of evapotranspiration showed 5. 1mm, 4. 5mm, and 6.4mm for the mulching-irrigation, the mulching-nonirrigationl, and the nonmulching-irrigation plot respectively. 5. It was confirmed that the higher correlationship exists between the weight of dried leaves and the amount of evapotranspiration, and between the weight of dried leaves and the coefficient of evapotranspiration with the function of logarithms. The coefficient of evapotranspiration have a tendency to increase in proportion to the leaf area index. 6. The maximum coefficient of evapotranspration and the largest leaf area index showed 1. 45 and 5.5 respectively. The stage appeared maximum values was assumed to be before and after flowering. 7. The soil moisture extraction pattern has changed by the depth of root zone for the tobacco's growing. The soil moisture extraction influenced on the 20cm depth of soil after 15 days passed, the 30cm depth after 25 days passed and the whole root zone after 45 days passed from planting. It was shown in the only mulching-irrigation plot after S5days passed from planting that the rate of soil moisture extraction of 20cm layer was larger than that of 10cm layer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.2
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• pp.564-568
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• 2008

This study was conducted to investigate the effects of dietary Hewer's dried grain supplementation on growth performance and digestibility in growing pigs. A total of forty-eight pigs (19.3 kg, average initial body weight) were used during 42 days. Dietary treatments included: 1) CON (basal diet), 2) BDG5 (basal diet + 5 % brewer's dried grain) and 3) BDC10 (basal diet + 10 % brewer's dried grain). Each treatment had 8 replicates of 2 pigs per pen in a randomized complete block design. Growth performance was not affected by treatments. However, in nutrient digestibility, DM digestibility was higher in BDG5 treatment than CON and BDG10 treatments. Nitrogen digestibility was the highest in BDG10 treatment and among another treatments, also, BDG5 treatment was higher than CON treatment. And, energy digestibility was higher in BDG10 treatment than CON treatment. In conclusion, dietary brewer's dried grain supplementation is not reduced on growth performance and improved on nutrient digestibility.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.2
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• pp.133-138
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• 1996

To investigate the effects of inorganic phosphate ($P_2O_5$ 200kg/ha), fermented cow manures($P_2O_5$ 200kg/ha, 400kg/ha) and poultry manures($P_2O_5$ 200kg/ha, 400kg/na) levels mixed with sawdust on the soil changes and productivity of alfalfa monoculture, a field experiment arranged by randonmized complete block design was conducted at National Livestock Research Institute in Suwon, September, 1993 to December 1995. The results are as follows. S1. Soil pH was changed from 5.40(before experiment) to 6.17(fermented cow manure, $P_2O_5$ 400kg/ha), 6.76 (fermented poultry manure, $P_2O_5$400kg/ha) and 6.3l(inorganic phosphate, $P_2O_5$ 200kg/ha) at 0~5cm depth of subsoil, respectively. Organic contents after experiment were lower as a range of 2.41%~3.15% than those before experiment. 2. Total nitrogen contents of each treatment showed as 0.13%~0.16% at 0~5cm depth of subsoil comparing with before experiment(0.15%). Available phosphate content of inorganic phosphate($P_2O_5$200kgha) was highest as 405ppm. lowest as 125ppm(fermented poultry manure, $P_2O_5$ 200kg/ha) than before trial(205ppm). 3. K and Ca contents of after experiment were appeared to 0.22%~0.78% and 6.45%~9.45% comparing with before experiment(0.10% and 3.56%), respectively. 4. During two years, average DM yield of fermented cow rnanure($P_2O_5$ 400kg/ha) was highest as 11, 731kg/ha and lowest as 9, 017kg/ha at fermented poultry manure plot($P_2O_5$ 200kg/ha) with as sawdust, but no significant difference was found among treatment(P>0.05). 5. CP production, NEL and TDN yield of fermented cow manure($P_2O_5$ 400kg/ha) were highest as 2, 282kg/ha 69, 900kg/ha and 6, 392kg/ha, respectively, but no significant difference among treatment(P>0.05). 6. In inorganic contents of alfalfas, there was not show same tendency in accordance with treatments. As a results mentioned above, it was possible to use 200kg $P_2O_5/ha$ of fermented cow or poultry manure with sawdust instead of inorganic phosphae fertilizer.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.1
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• pp.19-26
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• 1997

To find out the residual effect of phosphate fertilization on botanical composition, mineral contents and mineral nutrient deprivation of pasture plants, this experiment was arranged as a randomized complete block design with six treatments(0-0, 50-50, 100-65, 150-65, 200-65 and 250-65kg $P_2O_5$/ha), those were composed of three P,O, fertilization level(0, 50 and 65kg P,OJha) after phosphate fertilization trial with six treatments(0, 50, 100, 150, 200 and 250kg $P_2O_5$/ha) from 1989 to 1992, and conducted at hilly land in Kwangju, Kyonggi Province 60m 1993 to 1994. The results obtained are summarized as follows: The botanical composition of pasture plants without phosphate fertilization was very poor. With increasing available phosphate of soil, the percentage of grasses and legumes were remarkably increased and weeds was decreased. With 150-65kg $P_2O_5$/ha application for two years, the average DM yield was composed of 80.6% grasses, 15.4% legume and 4.0% weeds, the percentage was similar to that of 200-65kg $P_2O_5$/ha. As available phosphate of soil increase, P, K and Mg content of pasture plants were increased, but Ca/P ratio was lowed and the other mineral contents tended not to be regular. The mineral nutrient contents deprived by DM yield was increased as available phosphate of soil was increased, but those were not different between 150-65 and 250-65kg $P_2O_5$/ha. However, mineral nutrient of $P_2O_5$,$K_2O$ and MgO were higher in 200-65 and 250-65kg $P_2O_5$/ha. Most of applied mineral elements were accumulated at a subsurface(0-2.5cm) of grasslands, and mineral tended to be decrease than that of soil chemical analysis before the experiment of residual effect of phosphate fertilization.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.1
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• pp.65-70
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• 1986

This experiment was carried out to identify the main pathogens infected with Piper sudangrass and to evaluate the qualitative and quantitative damage of the plants infected with leaf blight (Helminthosporium turcicum PASS) under different levels of nitrogen fertilizer (20, 30 and 40 kg/10a). The experiment was design as a randomized block design with 4 replications at experimental field of Livestock Experiment Station in Suweon, 1984. The results obtained are summarized as follows: 1. The main fungi isolated from sudangrass were identified as Helminthoporium turcicum and Collectotricum graminicolum, but 1 species fungus was not identified. 2. Leaf blight was first found on June 20 and appeared extremely in the regrowth plants from July to September. The rate of attack was associated with increasing of nitrogen fertilization (P<0.01). 3. Fresh and dry matter yields were as much as 47 and 38 percentage lower in leaf blight infected plants (disease severity: V) than those of no visible infection. 4. Concentrations of crude fat and crude protein were decreased in the plants infected with Helminthosporium leaf blight, but lignin content was increased. Dry matter and organic matter digestibility of the plants were negative correlated with the infection of leaf blight(P<0.01).

• Membrane Journal
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• v.18 no.3
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• pp.234-240
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• 2008

This work demonstrates the preparation of proton conducting crosslinked polymer electrolyte membranes by blending polystrene-b-poly(hydroxyethyl acrylate) (PS-b-PHEA) and poly(vinyl alcohol) (PVA) at 1 : 1 wt ratio. The PHEA block of the diblock copolymer was crosslinked with PVA using sulfosuccinic acid (SA) via the esterification reaction between -OH of membrane and -COOH of SA, as confirmed by FT-IR spectroscopy. Ion exchange capacity (IEC) continuously increased from 0.14 to 0.91 meq/g with increasing concentrations of SA, due to the increasing portion of charged groups in the membrane. In contrast, the water uptake increased up to 20.0 wt% of SA concentration above which it decreased monotonically. The membrane also exhibited a maximum proton conductivity of 0.024 S/cm at 20.0 wt% of SA concentration. The maximum behavior of water uptake and proton conductivity is considered to be due to competitive effect between the increase of ionic sites and the crosslinking reaction according to the SA concentration.

• Archives of Plastic Surgery
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• v.35 no.4
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• pp.360-366
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• 2008

Purpose: Botulinum toxin type A(BoTA) can block the release of vasoconstriction cotransmitters as well as acetylcholine in nerve terminal. The authors observed that BoTA increases flap survival by preventing sympathetic collapse of peripheral vessels. Methods: 10 Sprague Dawley rats were divided into control(n=5), and BoTA group(n=5). $3{\times}10cm$ sized random pattern cutaneous flaps were elevated on the dorsal side in both groups. In BoTA group, BoTA was injected into the flap via intradermal to subdermal route, 7 days before the flap elevation. Flap survival rates (survival area/total area) were measured 7 days after the elevation. Cutaneous blood flow was measured in proximal, middle and distal compartments of the flap using laser Doppler flowmetry initially, preoperatively, at immediate postoperation, and 7 days after flap elevation, respectively. Histological examination was performed 7 days after the flap elevation. The number and shape of the vessels were evaluated under microscope. Results: Mean flap survival was $53.18{\pm}6.58%$ in control group and $93.79{\pm}6.06%$ in BoTA group, displaying statistically significant difference(p=0.0008, p<0.05). In the control group, blood flow to the middle and distal compartments of the flap decreased significantly immediately after flap elevation. In the BoTA group, blood flow to the middle compartment did not decrease(p=0.002) and slightly decreased in the distal compartment(p=0.001). Cutaneous blood flow was significantly higher in all compartments of the flap in BoTA group than in control group, 7 days after the flap elevation. In histopathologic examination, greater number of vessels were noted in the BoTA group than in the control group. Conclusion: Botulinum toxin A can increase the survival of the random pattern cutaneous flap in rats by preventing the sympathetic collapse of peripheral vessels.

• Journal of radiological science and technology
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• v.43 no.5
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• pp.359-365
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• 2020

This study aimed to investigate the causes of bacterial growth to prevent infection caused by ultrasound gel and gel containers in contact with patients during ultrasonography. To investigate bacterial contamination during manufacturing or storage, we cultured ultrasound gels originally supplied from three manufacturers. To analyze bacterial growth according to the lapse of time and frequency of use of the ultrasound gel container, the gel and container were cultured at regular intervals every week for 4 weeks. In addition, to determine the source of infection, the examiner's hand was inspected with hand plate and the degree of bacterial contamination was measured before the test. As a result of the study, bacteria were not detected in the gel provided at the initial supply, and in the gel and gel container used repeatedly for 4 weeks, the same bacteria residing on the skin were identified in the examiner's hand, such as Staphylococcus epidermidis, Micrococcus luteus, Leuconostoc mesenteroid spp cremoris, Kocuria rhizophila, and etc. Separated strains were classified as those of the low- or non-pathogenicity; however, most of these strains may render fatal consequences to patients of lower level of immunity due to acquired tolerance to antibiotics. At week 1, when the number of tests was the highest, 44 colonies were identified, and at week 4, when the number of tests was the lowest, 4 colonies were identified. As r=0.994, it was found that the number of colonies increased as the number of tests increased. In conclusion, it was confirmed that the cause of the infection was not the ultrasound gel, but the examiner's hand. The ultrasound gel or gel container may be contaminated by skin flora of examiner's hands, which can cause opportunistic infection in patients with low immunity. The ultrasound gel or gel container may be contaminated by skin flora of examiner's hands, which can cause opportunistic infection in patients with low immunity. Therefore, it was confirmed that thorough hand disinfection was necessary to block healthcare-associated infections.