• Toxicological Research
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• v.8 no.1
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• pp.95-107
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• 1992

Basolateral and brush border membrance (BLM and BBM) vesicles of renal proximal tubules were prepared from adult male New Zealand White rabbits to develop an experimental for assessment of nephrotoxicity. PAH uptakes using BLMV, and glucose and leucine uptakes using BBMV were measured in the rabbits treated uranyl acetate. In addition, urinalysis and histopathological studies were performed to investigate the correlationship with the membrance vesicle uptakes.

• Bulletin of Food Technology
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• v.11 no.4
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• pp.61-69
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• 1998

간 독성 물질인 2-Nitropropane (2-NP)을 쥐의 복강내로 주사한 후에 조직에서의 지질산화(lipid peroxidation (LPO), malondialdehyde 와 4-hydroxyalkenal의 생산량)와 간 독성의 지표로서 혈청내의 soritol dehydrogenase(SDH) 활성을 측정하였다. 수많은 독성 물질에 대하여 방어효과를 보이는 멜라토닌(melatonin)을 2-NP 투여 30분전에 주사하여 2-NP에 대한 방어효과를 조사하였다. 2-NP 투여시에 LPO와 SDH 활성은 시간 (0, 4, 8, 24h) 및 2-NP의 농도 (0, 1, 2, 4mmol/kg)에 따라 증가하였고, 4mmol/kg의 2-NP을 투여한 24시간 후에는 간 (P<0.001), 폐 (P<0.05), 신장(P<0.001)에서 LPO가 유의적으로, 혈청에서의 SDH 활성은 470배 증가하였다. 멜라토닌을 농도에 따라 투여시(2.5, 5, 10 mg/kg) 간, 폐 신장에서 LPO가 간에 대하 발암성 물질인 2-NP가 지질산화도 유도 할 수 있으며, 약리적인 수준의 멜라토닌이 2-NP의 독성을 감소시킬 수 있음을 나타낸다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.28-28
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• 1992

브라디키닌은 체내에서 강력한 혈관 확장 작용을 일으키는 autacoid(local hormone)로서 혈압의 항상성 유지, 모세혈관 투과성 증진, 염증 및 통증 반응 등에 관여하고 여러 장관 평활근을 수축시킨다. 또한 septic 혹은 endotoxic shock의 여러 원인 물질로도 생각되어진다. 최근 rhinovirus로 인한 감기의 제증상 원인 물질로도 브라디키닌이 주목을 받고있다. 이와같이 브라디키닌온 다양한 질병에 있어 중요한 원인 물질로 여겨지므로 브라디키닌 길항제들은 한두 질병의 치료제로 개발될 가능성이 높음이 강력히 제시되고 있는 실정이다. 이의 개발을 위해서 브라디키닌 수용체에 대한 연구는 필수적이라고 할 수 있다. 본 연구는 두 부분으로 나누어 진행중인데 첫째, 이제까지 보고된 브라디키닌 길항 물질들은 대부분이 브라디키닌의 특정 아미노산 잔기를 치환시킨 펩타이드 유도체로서 이들을 경구 투여시 peptidase어 의하여 쉽게 분해되고 또한 부분적인 효능제 활성을 갖는 불리한 점을 감안하여, 비펩타이드성 브라디키닌 길항제를 개발할 목적으로 한방 및 민간에서 자주 사용되어온 생약중에 브라디키닌 작용에 선택적 길항효과가 있는 물질을 검색한 바 활성을 보인 황금으로부터 작용 성분을 추적중에 있다. 둘째, 브라디키닌 수용체를 순수하게 분리 정제하기 위한 첫 단계로서 이 수용체의 결합시험(binding assay) 방법을 확립하고 더불어 여러 조직내(흰쥐의 여러 기관, 토끼 및 사람의 신장)의 브라디키닌 수용체의 분포를 파악하는 일이다. 횐쥐 조직의 실험 결과로부터 신장에 브라디키닌 수용체가 많이 분포함을 확인되었고 향후 토끼 신장으로부터 동수용체를 분리하고자 한다. 또한 토끼 신장의 근위세뇨관일차배양세포을 이용하여 브라디키닌의 신장에서의 작용기전도 살펴보고 있다.+}$, $Na^{+}$, NH$_{4}$$^{+}$ 및 H$^{+}$) 수용액 메디움에서의 Cd(II), Mg(II) 및 Zn(II)의 Dowex 1-X8, Cl$^{-}$ 수지에 대한 흡착은 역시 어떤 메디움에서도 Cd(II) 흡착이 제일 크며, 다음이 Zn(II) 이고 착이온을 형성않는 Mg(II)이 제일 작았다. 한편 메디움 종류별 D값의 크기순위는 H$^{+}$>K$^{+}$> $Na^{+}$>NH$_{4}$$^{+}$이였다. 메디움의 종류에 따라 D값의 차이가 나는 것은 금속이온의 착이온 형성과 금속이온의 용액내에서의 이온종의 상태와 관련이 있다고 생각된다. 마. MCl(M:K$^{+}$, $Na^{+}$, NH$_{4}$$^{+}$ 및 H$^{+}$)과 MNO$_{3}$ 용리액에 의한 Cd(II), Mg(II) 및 Zn(II)의 용리는 예상한 바와 같이 MCl에서 작은 Dv 값을 갖는데, 이것은 CdCl$_{4}$$^{2-}$ 착이온을 형성하거나 ZnCl$_{4}$$^{2-}$ , ZnCl$_{3}$$^{-}$같은 이온과 MgCl$^{+}$, MgCl$_{2}$같은 이온종을 형성하기 때문인것 같다. 한편 어떠한 용리액에서던지 NH$_{4}$$^{+}$의 경우

• Korean Journal of Weed Science
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• v.12 no.2
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• pp.173-182
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• 1992

Regardless of the test species, germination was adversely affected by the different concentrations of the acidic and neutral fractions of sunflower root exudates while the basic and aqueous fractions had no effect on germination. In both test species, root lengths were inhibited slightly more than shoot lengths. Significant reduction in fresh weights of the test species was observed when the test species were treated with the acidic and neutral fractions but not with the basic and aqueous fractions. Six compounds, hydroquinone, ${\beta}$-resorcyclic acid, vanillic acid, caffeic acid, salicylic acid, and quercetin, were characterized from the acidic fraction. Seven compounds, hydroquinone, gentisic acid, ${\beta}$-resorcyclic acid, vanillic acid, caffeic acid, ferulic acid, and quercetin, were elucidated from the neutral fraction.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.185-190
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• 1999

Autotoxic substance(s) from alfalfa(Medicago sativa L.) plants reduces germination and growth of adjacent new alfalfa after alfalfa. The autotoxic chemical(s) in alfalfa are clearly unknown. Our objective was to improve the sensitivity of an alfalfa seedling bioassay for evaluating autotoxic leaf extracts. We determined critical extract concentrations that inhibit seed germination and seedling growth, compared two different culture media, and evaluated the effects of extract sterilization on the sensitivity of the assay, by using streptomycin and autoclaving method. An agar medium in petri plate gave better responses of germination and seedling growth to the extracts than using filter paper in the plate. On agar medium, the concentration of extract required to reach 50% inhibition of root length was 2.7 g $kg^{-1}$, and of germination and hypocotyl length were 3.8 and 9.9 g $kg^{-1}$, respectively. Leaf extracts with 100 ppm streptomycin stimulated germination significantly compared to Leaf extract alone but reduced root length of control by 43%. Root length was more sensitive to the autotoxin(s) than was germination or hypocotyl length. These results suggest that agar medium mixed with extract and sterilization by autoclaving could be improved the consistency and precision of bioassay, and that root length was the best parameter of autotoxic effect of alfalfa leaf extract.

• The Science & Technology
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• v.29 no.5 s.324
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• pp.76-77
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• 1996

염소소독을 한 수돗물에는 THM이란 오염물질이 잔류하게 되는데 간독성을 유발하는 이 HTM이 신장에도 독성을 일으킨다는 사실을 밝혀낸 서울대 약학과 정진호교수가 이달의 과학자로 뽑혔다. 최근 혈소판도 화학물질에 의해 독성반응을 일으킨다는 사실을 세계 최초로 밝혀낸 정교수는 혈소판과 혈관의 상호작용에 대한 연구로 분주한 나날을 보내고 있다.

• The Korean Journal of Ecology
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• v.17 no.1
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• pp.23-35
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• 1994

To investigate phytotoxic substances in Artemisia argyi, the donor plant, and their biological activities, seed germination and seedling growth of receptor plants such as Arundinella hirta, Echinochloa crus-galli, Rumex crispus and Lactuca sativa were examined at different concentrations of aqueous extracts of the donor plant. Germination of four receptor species was inhibited by the extracts, while seedling growth was decreased to a lesser degree than in the germintion test. Germination, seedling growth and dry weight growth of Achyranthes japonica grown in pot were proportionally inhibited by the extracts. Volatile substances emitted from A, argi plant caused slight inhibition in the germination and seedling growth of the receptor species. Essential oil of the plant extracted by Karlsruker's apparatus inhibited growth of microorganisms and callus growth of Pinellia ternata and Oryza sativa. The GC /MS method was employed for analysis and identification of allelochemicals from A. argyi leaves. Sixty-one chemical substances such as a-pinene, camphene, 1. 8-cineol, etc. were identified from essential oil of A. argyi. The results of this experiment on seed germination, seedling growth, microorganism culture and tissue culture indicated that naturally occurring chemical substances from A. argyi would be responsible for the growth inhibition of plants studied.

• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.121-128
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• 1998

Ochratoxin A (OA) is a mycotoxin produced by Aspergillus ochraceus as well as other molds. It is a natural contaminant of mouldy food and feed. OA has a number of toxic effects, the most prominant being nephrotoxicity. Futhermore, OA is immunosuppressive, genotoxic, teratogenic and carcinogenic. OA inhibits protein synthesis by competition with phenylalanine in the phenylalanine-tRNA aminoacylation reaction. Recently, lipid peroxidation induced by OA has been reported, indicating that the lesion induced by this mycotoxin could be also related to oxidative pathway. Since it seems impossible to avoid contamination of foodstuffs by toxigenic fungi, detoxification and detoxication of OA are needed. In this study we investigated the protective effects of aspartame (Asp), phenylalanine (Phe), polyphenol 70S (PP) and aloe extract (AE) on the nephrotoxicity induced by subacute exposure to the OA. Asp and Phe are structural analogues of OA. PP, an ingredient of Green Tea and AE have been known as antioxidant and radical scavenger. Phe (40 mg/kg, i.p.) and Asp (25 mg/kg, p.o.) were administered to Sprague-Dawley rats simultaneously with OA (2.0 mg/kg, p.o.) for 2 weeks. PP (200 mg/kg, p.o.) and AE (50 mg/kg, i.v.) were pretreated before administration of OA, for 2 weeks and 3 days, respectively. Using enzymuria, BUN level, creatinemia and histophathologic examination as indices of renal damage, we observed that all of four compounds prevented the nephrotoxic effects induced by OA. It seems that structural analogues of OA such as Asp and Phe have better protective effect on the nephrotoxicity of OA than antioxidants. These results indicate that 1) formation of free radical and lipid peroxidation are likely to be involved in the nephrotoxicity of OA in vivo, 2) Asp, PP and AE might be used for prevention of renal lesions in cases of ochratoxicosis.

• 한국체육학회지인문사회과학편
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• v.54 no.5
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• pp.769-780
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• 2015

This study investigated the changes in inflammatory mediators, immunocompetent cells and bone merrow progenitor cells by the magnitude of muscle damage and type of the muscle contraction in the elderly. Twenty older adults who had not been involved in a resistance-training program at least 6 months prior to the present study were assigned to eccentric exercise group (ECC, n=10) and concentric exercise group (CON, n=10). All subjects performed 10 sets of 6 maximal isokinetic eccentric (ECC 1) or concentric (CON) contractions with the non-dominant arm in a randomized, with 4 wk between bouts (ECC 2). Skeletal muscle damage index (ROM, VAS, Plasma CK), inflammation mediators (TNF-α, IL-1, IL-6), immunocomperent cells (CD3+, CD4+, CD8+, CD19+), bone merrow progenitor cell (CD34+) and leukocytes were measured before, immediately after, 2, 24, 48, 72, and 96 h after exercise. Changes in ROM and VAS were greater (P<.05) after ECC 1 than CON and ECC 2. Increases in TNF-α and IL-6 were greater (P<.05) 24, 48 and 72 h after ECC 1 than CON and ECC 2. Increases in neutrophils were greater (P<.05) 2 h after ECC 1 than CON and ECC 2. It was confirmed that muscle damage was greater following eccentric than concentric contractions as well as first bout than second bout in the elderly, and suggested that TNF-α, IL-6 and neutrophils should closely correlate with magnitude of muscle damage.

• The Korean Journal of Rheology
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• v.6 no.2
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• pp.129-138
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• 1994

공압출되는 sheet die에서 고분자 물질의 비등온 유동유동을 수치모사하였다. 유변학 적 식으로 power-law model을 사용하였고, 격자생성법을 이용한 유한차분법을 사용하였다. 수치계산을 통해 수축채널에서의 온도 분포를 구해보고 점도가 채널에서의 온도 분포를 구 해 보고 점도가 채널에서의 압력강하 및 신장속도에 미치는 영향을 알아보았다. 압력강하는 외부 유체의 점도 및 heat dissipation의 영향을 크게 받았다. 신장속도는 외부 유체의 점도 가 증가함에 따라 커진 반면 내부 유체의 점도가 증가함에 따라 커진반면, 내부 유체의 점 도증가에 따라 감소하였고, heat dissipation에 의해 증가하였다.