• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.206-206
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• 1994

1차년도에 F9 EC cell의 분화유도 시스템을 확립한뒤 계속적으로 해양생물로 부터 분리한 여러가지 물질을 처리하여 세포의 형태 변화 및 분화 관련 유전자 즉 laminin Bl, type IV collagen, RAR-$\beta$ 의 발현을 조사하였다. 그 결과 다수의 물질이 F9 세포를 분화시키는데 효과가 있는 것으로 나타났으며, 효과있는 물질들에 대한 구조분석이 계속적으로 실시되고 있다. 뿐만 아니라 분화효과가 있는 물질중에서 그 구조적으로 특이한 성질을 가진 물질에 대하여 이 물질이 암세호의 분화에 미치는 기작에 대해 조사하였다. 구체적인 실험내용을 요약하면 다음과 같다. 1. F9 EC cell에 스크리링할 물질의 처리 후 형태 변화 관찰 2. 분화 maker 유전자의 발현 조사 3, 작용 기작에 대한 조사

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.125-128
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• 2002

강변 여과 취수 방식을 활용한 국내 충적층 지하수의 이용을 위해서는 망간에 대한 수처리가 주요 사항인 것으로 나타났다. 강변 여과 방식 취수 원수의 망간 함량은 먹는 물 수질 기준을 부분적으로 상회하지만, 이러한 망간에 대한 저감 처리는 기존의 지표수를 취수하여 처리하는 수처리 공정에 비해서는 상대적으로 효율적인 것으로 판단된다. 실제로, 국내 최초의 강변 여과 방식 취수를 활용하는 창원시 대산 지구 원수는 공기 포기, 급속 여과, 활성탄 여과를 통해, 먹는 물 수질 기준을 상회하는 망간을 효과적으로 처리하고 있는 것으로 평가되었다. 특히, 활성탄 여과가 망간제거 효과를 보이는 점은 특이한 현상으로, 활성탄 내에서도 철 관련 박테리아에 의한 망간 처리 가능성을 시사하고 있다. 또한 망간과 함께 나타나는 철 성분은 망간의 침전 처리에 긍정적인 면으로 작용하는 것으로 판단된다. 한편, 고령군 다산면에서의 실증 플랜트 실험은 전염소처리와 망간접촉여과를 통해 먹는 물 기준 이하의 망간 함량을 확보하는 데는 성공하였으나, 이러한 처리 기작이 안정화되는데 까지는 약 3개월 내외의 시간이 요구되는 것으로 나타났다.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.521-525
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• 1993

To elucidate adsorption of proteins and examine the molecular behavior of protein molecules at interfaces, various proteins at the air-water interface were studied. The adsorption data of bovine serum albumin intermediates indicated that the conformational state of a protein played an important role in adsorption of proteins at interfaces. The adsorption behavior of succinylated beta-lactoglobulin indicated that the increase in the net negative charge of the protein significantly inflenced both the kinetics and thermodynamics of adsorption. The adsorption kinetics of beta-casein showed that the salt that induced break-down of water structure decreased the rate of adsorption.

• Korean Journal of Food Science and Technology
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• v.5 no.3
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• pp.157-162
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• 1973

Mode of action study of irradiation was performed with potato tuber slices, $1mm{\times}1.5cm,$ aged on moist filter paper under aseptic technique. The time courses of invertase activity, nucleic acids and respiratory activity were determined, and sensitivities of these three processes to ionizing radiation were measured. None of those processes was severely inhibited by the dosage suppressing cell division. The result of $^3H-thymidine$ incorporation suggests that the reaction site of ionizing radiation might be existent during mitosis or $G_2$ period.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.76-83
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• 1998

The most remarkable aspect in the hormesis law is that dose of harmful agents can produce effect that are diametrically opposite to the effect found with high doses of the same agent. Minute quantities of a harmful agent bring about very small change in the organism and control mechanisms appear to subjugate normal processes to place the organism in a state of albert and repair. The stimulated organism in more responsive to changes in environmental factors than it did before being alerted. Routine functions, including repair and defense, have priority for available energy and matetial. The alerted organism utilizes nutrients more efficiently, grows faster, shows improved defense, and lives longer. Accelerated germination, sprouting, growth, development, blooming and ripening, and increased crop yield and resistance to disease are found in plants. Another concept supported by the data in that low doses of ionizing radiation provide increased resistance to subsequent high doses of radiation. The hormesis varies with subject plant, variety, state of seed, environmental and cultural conditions, physiologic function measured, dose rate and total exposure. The results of hormesis are less consistently found, probably due to the great number of uncontrolled variables in the experiments. The general dosage for radiation homlesis in about 100 (10 to 1,000) times ambient or 100 (10 to 1,000) times less than a definitely harmful dose, but these must be modified to the occasion. Although little is known about most mechanisms of homzesis reaction, overcompensation of repair mechanism is offered as one mechanism.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.369-374
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• 2021

Brown blotch disease of oyster mushrooms is caused by tolaasin and its analog peptide toxins which are produced by Pseudomonas tolaasii. Tolaasin peptides form pores in the plasma membrane and destroy the fruiting body structure of mushroom. Lysis of red blood cells, hemolysis, can be occurred by cytotoxic activity of tolaasin. The hemolytic activity of tolaasin is inhibited by metal ions, such as Zn²⁺ and Ni²⁺. When Gadolinium ion was added, a biphasic effect was observed on tolaasin-induced hemolysis, an increase in hemolysis at submillimolar concentrations and an inhibition at millimolar concentrations. The mechanism of gadolinium ion-induced inhibition of tolaasin activity may not be similar to those of the inhibitions by other metal ions. Since gadolinium ion has been reported to change a lateral pressure of lipid membrane by binding to the negative charges of membrane lipids, it may not directly work on the tolaasin channel gating, but rather decrease the stability of tolaasin channel by increasing firmness of membrane.

• KOREAN POULTRY JOURNAL
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• v.19 no.4 s.210
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• pp.99-102
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• 1987

가죽의 생산력을 향상시키고 도체조성을 개선하기 위해 현재 사용되고 있는 다양한 성장촉진제에 대하여 그 효과와 가능한 작용기전에 관해 정리하였다. 항생제는 여러 가축에 가장 널리 이용되고 있으며 성장 촉진 효과로 잘 알려져 있다. 그러나 가능한 내성문제 등 여러가지 우려되는 문제점으로 사용에 제한을 받고 있으며 따라서 부작용이 없는 새로운 항생제의 개발노력은 계속적으로 경주되어져야 한다고 본다. 생균제는 항생제의 대체 가능한 첨가제로서 장내에서 유해한 미생물들을 억제조절하고 반면 유익한 미생물 성장을 도와 성장을 촉진한다. 성장호르몬의 합성효과에 의한 성장촉진 및 체조성 개선 효과는 상당한 관심의 대상으로 연구가 되고 있으며 최근의 연구결과에 의하면 동물에 성장호르몬 투여는 성장촉진 효과와 더불어 근육생산을 늘리고 지방축적을 감소시켰다고하며 또한 유생산에도 상당한 증가효과가 있었다고 한다. 대부분 성호르몬인 합성호르몬은 주로 육생산 가축에서 성장촉진 및 도체품질 향상 목적으로 쓰이는데 보통 사료에 첨가되거나 직접 투여되기도 한다. 효모 배양물은 특히 어린 동물에서 증체 향상 효과가 보고되고 있는데 이런 효과는 효모의 효소에 의한 소화율 향상이나 비타민 B군등 미량 영양소의 직접적인 공급 효과로 풀이된다. 전체적으로 성장촉진 목적으로 이용되는 여러 제제들은 그 명확한 작용기작 규명 등 앞으로 보다 많은 연구노력이 이루어져야 할 것으로 본다.

• Korean Journal of Crystallography
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• v.16 no.2
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• pp.66-74
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• 2005

Marine natural products with various bioactivities are featured with similar structure to the common secondary metabolites and generally modified by halogenides, such as chloride, bromide, and iodide ions. Vanadium haloperoxidase is a key enzyme for the production of marine natural products and a metalloenzyme which requires a cofactor of vanadate. This review will cover isolation of vanadium haloperoxidase and the protein structures, as well as reaction mechanism of the metalloenzyme. Finally, reactivity of vanadium haloperoxidase and the biosynthesis of the secondary metabolites of indole, terpenoids, and acetogenins will be described.

• The Journal of Natural Sciences
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• v.9 no.1
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• pp.25-29
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• 1997

To study the mechanism of lipocortin-1, the 37 kDa protein, one of the annxin superfamily thought to be a second messenger during the Glucocorticoid dependent anti-inflammatory action, the gene for lipocortin-1 binding protein was isolated using the yeast two hybrid assay, the yeast based genetic assay recognizing the protein-protein interaction. The results showed that this gene has a weak homology to the for the human serine proteinase.

• Journal of Wetlands Research
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• v.20 no.1
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• pp.63-71
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• 2018

The particle filtration mechanisms in an infiltration trench should be varying due to the different hydraulic conditions during stormwater runoff. The understanding of these variations associated with different filtration mechanisms and their effect on the particle removal efficiency is of vital importance. Therefore, a LID (Low Impact Development) system comprising of an infiltration trench packed with gravel and woodchip was investigated during the monitoring of several independent rainfall events. A typical rainfall event was divided into separate regimes and their corresponding flow conditions as well as filtration mechanisms in the trench were analyzed. According to hydraulic conditions, it was found out that filtration changes between vertical and horizontal flows as well as between unsaturated, saturated, and partially-saturated flows. Particle separation efficiency was high (55-76%) and was mainly governed by physical straining during the unsaturated period. It was then enhanced by diffusion during the saturated period (75-95%). When the trench became partially saturated at the end of the rainfall event, the efficiency decreased which was believed to be due to the existence of a negatively charged air-water interface which limited the removal to positively charged particles.