• 제목/요약/키워드: Homogenate

검색결과 353건 처리시간 0.029초

Protein Phosphatase 2A의 활성화에 미치는 Lipid Bilayer Membrane의 저해 효과 (Inhibitory Effect of Lipid Bilayer Membrane on Protein Phosphatase 2A)

  • 남기열
    • KSBB Journal
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    • 제7권4호
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    • pp.302-307
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    • 1992
  • protein phosphatase 2A는 bovine brain homogenate의 세포질 fraction에서 얻어졌다. 기질로서 인산화된 histione H1을 이용하여 측정한 phosphatase 의 활성은 dipalmitoyIphophatidylcholine(DPPC) 혹은 phosphatidylserine/DPPC의 혼합물로 구성된 liposome의 존재하에서 저해되었다. Protein phosphatase 2A의 lipid membrane에의 결합은 다중층 지질막의 혼합물 계에서 liposome 의 양이 증가함에 따라서 상등액 중의 phosphatase의 활성이 감소하는 것으로 확인할 수 있었다. 또한 [$^{125}I$]protein phosphatase 2A가 liposome과 동시에 용출되는 것으로도 확인되었다. 그러나 liposome에 대한 protein phosphatase의 친화력은 높지 않았다. 한편, okadaic acid와 liposome은 협동으로 phosphatase의 활성을 감소시켰다. 이것은 okadaic acid가 lipid membrane이나 membrane에 결함한 phosphatase에는 결합하지 않는다는 것을 의미한다. 그러므로 lipid membrane에 의한 protein phosphatase 2A의 활성 저해 효과는 phosphatase 2A와 lipid membrane과의 결합에 의한 것이라고 설명될 수있다.

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디클로페낙 프로드럭들의 흰쥐 피부 투과 (Rat Skin Permeation of Diclofenac and its Prodrugs)

  • 도희정;조원제;용철순;이치호;김대덕
    • Journal of Pharmaceutical Investigation
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    • 제31권2호
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    • pp.95-100
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    • 2001
  • Various alkyl ester prodrugs of diclofenac were synthesized in order to investigate the relationship between their skin permeation characteristics and physicochemical properties. Solubility in various vehicles was measured at room temperature. 1-Octanol/water partition coefficients (Log P) and capacity factors (k') were measured to determine the lipophilicity of the prodrugs. Stability of prodrugs in the skin extract and homogenate was also investigated before conducting the skin permeation studies. Increases in the Log P and capacity factor values were observed when alkyl esters of diclofenac were prepared. Since the aqueous solubility of the prodrugs was not high enough, they were saturated in propylene glycol (PG) for skin permeation studies. Prodrugs were rapidly metabolized to diclofenac, both in skin homogenate and in dermal extract of skin. The skin permeation rate of alkyl ester prodrugs was significantly higher than diclofenac with shorter lag time. Moreover, a parabolic relationship was observed between the permeation rate and the log P values of prodrugs, and the maximum flux was achieved at a log P value of around 4.0.

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Bacillus thuringiensis subsp. sotto의 내독소 결정체 용해 과정 및 활성기작과 항원 발현 양상 (In Vitro Dissolution and Proteolytic Activation of $\delta$-endotoxin and Antigenic Expression Pattern of Bacillus thuringiensis subsp, sotto)

  • 남기범;조재민;홍순복;이형환;조명환
    • 한국미생물·생명공학회지
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    • 제23권6호
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    • pp.730-736
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    • 1995
  • The solubilization and proteolytic process of $\delta $-endotoxin was analvsed to compare the biochemical property of the toxin isolated from B. thuringiensis subsp. sotto. The purified crystals were dissolved in 50 mM carbonate buffer containing 10 mM dithiothreitol at pH 10 for various times. The electrophoretic pattern showed that a rapid disappearance of 138 kDa protein band. This disappearance of protein with high molecular weight was accompanied by the appearance of new protein fragment with 104 kDa, 60 kDa, and 25 kDa. For proteolvtic processing, the soluble crystals were digested with trypsin for various times. The soluble crystal protein of 104 kDa was completely disappeared. However, the protein fragment of 60 kDa and 25 kDa still remained after complete proteolysis. The comparative immunoblot analysis showed that the antiserum against intact crystals showed strong immunoreactivity to the homologous inclusion protein of 138 kDa, 104 kDa, and 25 kDa, and to the intact spores of 221 kDa and 138 kDa, but not to the vegetative cell homogenate. The sera against crystals and spores had no immunoreactivity to the vegetative cell homogenate.

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인삼(人蔘)이 흰 생쥐의 운동능력(運動能力) 및 유산생성량(乳酸生成量)에 미치는 영향(影響) (The Effect of Ginseng on the Physical Performance and Lactic Acid Production in Mice)

  • 홍성일;박해근
    • The Korean Journal of Physiology
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    • 제9권1호
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    • pp.77-82
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    • 1975
  • This experiment was carried out to observe a biological effect of ginseng on the weight gain, physical performance and lactic acid production after exercise in mice. A group of mice weighing about 19 gm was divided into ginseng and cotrol group. on the treadmill (Exp. I & II) and LDH activity of liver and heart homogenates (Exp. II) were determined. Results are summerized as follows; 1. Body weight gain was greater id ginseng group than in control and the difference was statistically significant at 9th and 16th days of experimental period. 2. Maximal running time of ginseng was found to be longer than that of control (p<0.05) in experiment I and the experiment II also revealed the significant increase in maximal running time in ginseng group. 3. Bloo lactate concentration of 48 hour-rest from physical exertion was lower in ginseng group than in control (p<0.05). 4. LDH activity in liver homogenate was lower compared to control group, but in heart homogenate, it was greater in ginseng group. Above findings may be concluded tat the range of biological dose (20 mg/mice/day) of ginseng powder stimulated the body weight gain and increase of physical performance and its mechanism might be attributable to a lower level of blood lactic acid. The adaptive change of LDH activity also contributed to the change in lactate level in blood and tissue.

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Preparation of Highly Water Soluble Tacrolimus Derivatives: Poly(Ethylene Glycol) Esters as Potential Prod rugs

  • Chung, Yong-Seog;Cho, Hoon
    • Archives of Pharmacal Research
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    • 제27권8호
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    • pp.878-883
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    • 2004
  • Tacrolimus (FK506), which is isolated from Streptomyces tsukubaensis, is a new potent immu-nosuppressant. Because of poor solubility in water, the conventional intravenous dosage forms of tacrolimus contain surfactants such as cremophor EL (BASF Wyandotte Co.) or hydroge-nated polyoxy 60 castor oil (HCO-60) which may cause adverse effects. This study relates to a polymer-tacrolimus conjugate, which can be dissolved in water, formed by chemically binding the sparingly soluble drug, tacrolimus, with the water soluble polymer, methoxypoly(ethylene glycol) (mPEG). Water soluble tacrolimus-mPEG conjugates have been synthesized and shown to be function in vitro as prodrugs. These conjugates are in the form of an ester wherein the 24-, 32- or 24,32-positions are esterified. The desired 24-, 32- or 24,32-esterified com-pounds were obtained by initially acylating of tacrolimus with iodoacetic acid at the 24-,32-, or 24,32-positions and then reacting the resulting acylated tacrolimus with a mPEG in the pres-ence of a base such as sodium bicarbonate. These conjugates were converted again into tac-rolimus by the action of enzymes in human liver homogenate, and the half-lives of the conjugates are approximately 10 min in the homogenate, indicating that the esterified tacroli-mus derivatives may be practically applicable as a prod rug for the immunosuppressant.

Autoxidation Products of Phytofluene in Liposome and Conversion of Phytapentaenal to 4,5-Didehydrogeranyl Geranoic Acid in Pig Liver Homogenate

  • Kim, Seon-Jae
    • Preventive Nutrition and Food Science
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    • 제5권4호
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    • pp.234-238
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    • 2000
  • The cleavage products formed by autoxidation of phytofluene were evaluated in order to elucidate possible oxidation products of phytofluene under oxidative conditions. Phytofluene solubilized at 50$\mu$M in liposomal suspension was oxidized by incubating at 37$^{\circ}C$ for 72 h. Among a number of oxidation products formed, five products in the carbonyl compound fraction were identified as 6, 10, 14-trimethylpentadeca-3,5,9,13-tetraen-2-one, phytapentaenal, 5,9,13,17-tetramethyloctadeca-2,4,6,8,12,16-hexaenal, 5,9,13,17-tetramethyloctadeca-2,4,8,12,16-pentaenal, 2,7,11,15,19-pentamethylicosa-2,4,6,10,14,18-hexaenal and 4,9,13,17,21-pentamethyldocosa-2,4,6,8,12,16,20-heptaenal. These correspond to a series of products formed by cleavage in the respective eight conjugated double bonds of phytofluene. Also, 4,5-didehydorgeranyl geranoic acid was formed by autoxidation of phytofluene in liposomal suspension. The pig liver homogenate had the ability to convert phytapentaenal to 4,5-didehydrogeranyl geranoic acid, comparable to the conversion of all-trans-retinal to all-trans-retinoic acid. These results suggest that phytofluene is cleaved to a series of long-chain and short-chain carbonyl compounds under the oxidative condition in vitro and that phytapentaenal is further enzymatically converted to 4,5-didehydrogeranyl geranoic acid.

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야생초 추출물에 의한 간장내 활성산소 생성과 항산화 효소계 조절에 관한 연구 (Modulation of Hepatic Lipid Peroxidation and Antioxidant Defenses by Wild Plants Extracts)

  • 이상영;김성완;김종대
    • 생약학회지
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    • 제28권1호
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    • pp.48-53
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    • 1997
  • This study was performed to elucidate the possible antioxidative effects of several wild plant extracts. Wild plants were extracted with methanol or water using general method. In first experiments, antioxidative effects were measured by lipid peroxidation using rat brain homogenate. Coptis japonica extract showed the highest antioxidative activity among the 15 wild plant extracts. In second experiments, rats were fed on the semipurified diets with or without Coptis japonica extracts at the level of 0.5% for 4 weeks. MDA production of liver homogenate were significantly lower in the rats fed Coptis japonica extracts (P<0.05). Cytosolic catalase. GPX, and SOD activities were not changed, whereas the activities of GST and glutathione level were significantly higher in rats fed Coptis japonica extracts (P<0.05). These results suggest that Coptis japonica extract has an antioxidative effect through increasing GST activity and glutathione level and decreasing MDA production.

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감귤과피 물 균질액을 첨가한 빵의 품질특성 (Quality Characteristics of Bread with Citrus Peel Water Homogenate)

  • 권수경;이예경;김순동
    • 동아시아식생활학회지
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    • 제12권5호
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    • pp.397-406
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    • 2002
  • 감귤과피 분말을 l~5% 함유하는 물 균질액을 첨가한 빵의 품질특성을 조사하였다. 반죽의 pH는 첨가량이 증가할수록 낮아졌으며 산도는 반대로 높아졌다. 반죽의 부피와 빵의 loaf volume은 첨가량이 높아질수록 감소하였다. 3% 첨가빵의 total carotenoids, hesperidin 및 naringin 함량은 각각 0.14 mg%, 38.4 mg% 및 25.3 mg%이었다. 빵의 hardness는 감귤과피 분말의 첨가량이 증가할수록 높았다. 1%를 첨가한 경우의 strength는 대조군과 차이가 없었으며 그 이상으로 첨가할수록 높아졌다. Cohesiveness는 1% 첨가는 대조구와 차이가 보이지 않았으나 3~5% 첨가구는 크게 감소하였다. Springiness는 0, 1 및 3% 첨가는 유의적 차이를 보이지 않았으나 5% 첨가군에서는 현저히 낮았다. 색상, 맛, 향, 씹힘성 및 종합적인 기호도로 평가한 결과 3% 첨가구가 가장 양호하였다.

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