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Design and Synthesis of Novel 2'(β)-Fluoro-3'(α)-hydroxy-threose Nucleosides: Iso-FMAU Analogues as Potent Antiviral Agents

  • Kim, Seyeon;Jee, Jun-Pil;Hong, Joon Hee
    • 통합자연과학논문집
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    • 제8권2호
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    • pp.99-106
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    • 2015
  • Novel 2'(${\beta}$)-fluoro-3'(${\alpha}$)-hydroxy-threose nucleosides (iso-FMAU) as antiviral agents were designed and racemically synthesized from Solketal. Condensation successfully proceeded from a glycosyl donor 9 under $Vorbr{\ddot{u}}ggen$ conditions yielded the nucleoside analogues. Ammonolysis and hydrolysis of isopropylidene protection group gave the desired nucleoside analogues 12, 15, 18, and 19. The antiviral activities of the synthesized compounds were evaluated against the HIV-1, HSV-1, HSV-2 and HCMV. Compound 12 displayed some anti-HCMV activity ($EC_{50}=24.7{\mu}g/ml$) without exhibiting any cytotoxicity up to $100{\mu}M$.

A proteomic approach to identify yeast proteins responding to accumulation of misfolded proteins inside the cells

  • Shin, Yong-Seung;Seo, Eun-Joo;Kim, Joon;Yu, Myeong-Hee
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2003년도 정기총회 및 학술발표회
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    • pp.57-57
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    • 2003
  • In growing number of diseases it has been shown that aggregation of specific proteins has an important role in pathogenesis of the disorder. This has been demonstrated in structural details with the liver cirrhosis of ${\alpha}$$_1$-antitrypsin deficiency, and it is now believed that similar protein aggregation underlies many neurodegenerative disorders such as autosomal dominant Parkinson disease, prion diseases, Alzheimer disease, and Huntington disease. ${\alpha}$$_1$-Antieypsin, a member of serine pretense inhibitor (serpin) family, functions as an inhibitor of neutrophil elastase.

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$\alpha$-Tocopherol과 Cysteamine 첨가가 돼지 미성숙난포란의 체외성숙, 체외수정 및 배발달에 미치는 영향 (Effect of $\alpha$-Tocopherol and Cysteamine on Maturation Male Pronuclear Formation and Development of Porcine Oocytes In Vitro)

  • 이경호;문승주;김재홍
    • 한국수정란이식학회지
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    • 제14권1호
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    • pp.9-15
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    • 1999
  • This study was conducted to investigate the effect of $\alpha$-tocopherol and cysteamine with Whitten's medium in supporting the development on in vitro maturation(IVM), in vitro fertilization (IVF) and in culture(IVC) on porcine oocytes. When the immature oocytes were cultured of $\alpha$-tocopherol for 40h, the nuclear maturation rates were 39, 4, 52.5 and 54.1%, respectivley. The nuclear maturation rates of treat groups were signficantly (P<0.05) higher than those of non-treat groups. After matureation, the oocytes were inseminated in vitro in medium 199 with ejaculated spermatoza for examination of sperm penetration, polyspermy, male pronuclear(MPN) formation, and cleavage rate. Sperm penetration rates of treat higher than the control groups(P<0.05), and MPN formation rates were significantly(P<0.05) higher on treated groups (24.3~53.1%) than control groups(14.2~21.4%). After insemination, the cleavage rates at 120hr were groups higher than control groups(P<0.05).

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Effects of Extrahepatic Cholestasis on Hepatic $\alpha$-D-Mannosidase Activity in Chronic Ethanol Intoxicated Rats

  • Si-Woo Bae;Chun-Sik Kwak;Chong-Guk Yoon
    • 대한의생명과학회지
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    • 제9권1호
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    • pp.21-27
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    • 2003
  • Hepatic subcellular $\alpha$-D-mannosidases activities and its Km and Vmax values were determined in chronic ethanol intoxicated rats with extrahepatic cholestasis induced by common bile duct ligation to manifest the biochemical background of alcohol drinking hazard under the hepatobiliary disease. In case of extrahepatic cholestasis, chronic ethanol intoxication in animals led to the increased activities of liver Golgi and microsomal $\alpha$-D-mannosidase as well as the Vmax values of these enzymes. However, the difference of Km values on hepatic subcellular enzymes were not found between the experimental groups. Therefore, the results indicate that the liver Golgi and microsomal $\alpha$-D-mannosidase may be more induced in chronic ethanol intoxication animals in case of cholestasis. Accordingly, the resulting data supported the fact that alcoholic drinks may led to enhancement of the hepatobiliary liver damage.

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EFFECTS OF SEVERAL CYTOKINES ON THE FUNCTIONS OF FETAL RAT OSTEOBLAST-LIKE CELLS IN VITRO

  • Han, Hee-Sung;Kim, Jung-Keun;Chang, Young-IL
    • 대한치과교정학회지
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    • 제25권6호
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    • pp.689-696
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    • 1995
  • Effects of several cytokines($IL-1{\beta},\;TNF_{\alpha},\;and\;IFN_{\gamma}$) have been examined on fetal rat osteoblast-like cells. To investigate whether cytokines play direct causal roles in production of lysosomal enzyme, fetal rat osteoblast-like cells were treated with $IL-1{\beta},\;TNF_{\alpha},\;and\;IFN_{\gamma}$, respectively or combined. And acid phosphatase was determined by biochemical method. Alkaline phosphatase was assayed to determine the effects of $IL-1{\beta},\;TNF_{\alpha},\;and\;IFN_{\gamma}$ on the expression of this enzyme. And also experiment of calcified nodule formation was performed to assess the effects of cytokines on the bone-forming activity of osteoblast-like cells in vitro. Acid phosphatase activity was significantly increased by the addition of $IL-1{\beta}\;and\;TNF_{\alpha}$, whereas decreased by $IFN_{\gamma}$. However, no significant change:: in alkaline phosphatase activity was observed when the osteoblast-like cells were treated with $IL-1{\beta}\;and\;TNF_{\alpha}$. Interestingly, $IFN_{\gamma}$ showed stimulatory effect on alkaline phosphatase activity. The number of calcified nodules was decreased by treatment of cultures with 1 ng/ml $IL-1{\beta},\;20\;ng/ml\;TNF_{\alpha}$, and 500 u/ml $IFN_{\gamma}$ continuously for 21 days, while considerable number of calcified nodules were formed in control group of osteoblast-like cell in culture for 21 days. These results seem to suggest that cytokines may play crucial roles in bone remodeling through the direct action on the osteoblast-like cell.

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Expression and Biochemical Characterization of the Bacillus thuringiensis Cry4B ${\alpha}1$-${\alpha}5$ Pore-forming Fragment

  • Puntheeranurak, Theeraporn;Leetacheewa, Somphob;Katzenmeier, Gerd;Krittanai, Chartchai;Panyim, Sakol;Angsuthanasombat, Chanan
    • BMB Reports
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    • 제34권4호
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    • pp.293-298
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    • 2001
  • Tryptic activation of the 130-kDa Bacillus thuringiensis Cry4B $\delta$-endotoxin produced protease-resistant products of ca. 47 kDa and ca. 21 kDa. The 21-kDa fragment was identified as the N-terminal five-helix bundle (${\alpha}1-{\alpha}5$,) which is a potential candidate for membrane insertion and pore formation. In this study, we constructed the recombinant clone over-expressing this putative pore-forming (PPF) fragment as inclusion bodies in Escherichia coli. The partially purified inclusions were composed of a 23-kDa protein, which cross-reacted with Cry4B antibodies, and whose N-terminus was identical to that of the 130-kDa protein. Dissimilar to protoxin inclusions, the PPF inclusions were only soluble when the carbonate buffer, pH 9.0, was supplemented with 6 M urea. After renaturation via a stepwise dialysis, the refolded PPF protein appeared to exist as an oligomer and was structurally stable upon trypsin treatment. Unlike the 130kDa protoxin, the refolded protein was able to release entrapped glucose from liposomes, and showed comparable activity to the full-length activated toxin, although it lacks larvicidal activity These results, therefore, support the notion that the PPF fragment that consists of ${\alpha}1-{\alpha}5$ of the activated Cry4B toxin is involved in membrane pore-formation.

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편백나무 건조 중 발생하는 휘발성 유기화합물의 항진균 및 항산화 활성 (Antifungal and Antioxidant Activities of Volatile Organic Compounds Generated During the Drying Process of Chamaecyparis obtuse)

  • 서영준;이재원
    • 미생물학회지
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    • 제48권4호
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    • pp.305-308
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    • 2012
  • 본 연구는 편백나무 건조 중 발생하는 휘발성 유기화합물로 구성된 응축수에 대해 항진균 및 항산화 활성을 평가하였다. 응축수는 hexane과 ethyl acetate로 각각 추출하였으며 추출액의 농도 100-500 mg/L에서 피부사상균에 대한 항진균 활성을 측정하였다. 추출액 농도가 증가할수록 항진균 효과도 증가하였으며 500 mg/L에서는 모든 피부사상균에 대해 높은 항진균 활성을 나타냈다. 추출용매에 따라서는 hexane으로 추출하였을 경우 높은 활성을 나타냈으며, 특히 Trichophyton rubrum에 대한 항진균 활성이 높았다. 항산화 활성을 측정한 결과 25 mg/L 이상의 농도에서는 90% 이상의 항산화 활성을 나타냈으며 추출용매에 따른 차이는 거의 없었다. 하지만 25 mg/L 이하의 농도에서는 hexane 추출물에서 높은 항산화 활성을 나타냈다. 각각의 추출물 구성성분을 분석한 결과 hexane 추출물의 주요 구성성분은 torreyol, alpha-cadinol, tau-cadinol이며, ethyl acetate 추출물의 주요 구성성분은 alpha-amorphene, alpha-cadinol, gamma-cadinene으로 나타났다.

마황 추출물의 항바이러스 활성 (Antiviral activity of methanol extract from Ephedra sinica Stapf)

  • 이도승;이동선
    • 한국식품저장유통학회지
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    • 제21권5호
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    • pp.735-739
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    • 2014
  • Newcastle disease virus(NDV) 감염된 baby hamster kidney(BHK) 세포에서 syncytium(합포체) 형성은 세포막 표면으로의 수송된 바이러스 당단백질 hemagglutinin-neuramidase(HN)에 의해 일어난다. HAU 값은 추출물의 농도가 25과 3.2 ug/mL 사이에서는 현저하게 감소하였으나, NDV 감염된 HAD(%)는 25 ug/mL 농도에서 광범위한 흡착능의 감소를 나타내 바이러스 당단백질의 세포내 생합성은 저해되지 않았다. 그러므로, 약용식물인 마황 메탄올 추출물이 바이러스 당단백질의 세포막으로의 수송과 함께 합포체 형성을 저해하여 항바이러스 작용을 하였다. 또한 마황 추출물의 저해활성을 조사한 결과 ${\alpha}$-glucosidase에 대한 추출물의 $IC_{50}$$18{\mu}g/mL$이었으며, ${\beta}$-glucosidase, ${\alpha}$-mannosidase, ${\beta}$-mannosidase에 대한 마황 추출물의 $IC_{50}$은 각각 60, 40, $150{\mu}g/mL$로 나타나 ${\beta}$-type glycosidases 보다 ${\alpha}$-type glycosidase에 대한 효소활성 저해능이 우수하였다. 따라서 $IC_{50}$농도에서는 세포내에서 당단백질 생합성은 저해되지 않으며 당단백질의 수송을 저해하는 것으로 판단되었으며 향후 항바이러스 관련 작용기작의 연구가 필요하다고 판단된다.

Temporal Pattern of cAMP Concentrations and α-Actin mRNA Expression in Skeletal Muscle of Cimaterol-Fed Rats

  • Kim, Y.S.;Duguies, M.V.;Kim, Y.H.;Vincent, D.L.
    • Asian-Australasian Journal of Animal Sciences
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    • 제10권5호
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    • pp.528-533
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    • 1997
  • Twenty four female Sprague-Dawley rats weighing about 190 g were used to examine changes in muscle cAMP concentrations and steady-state levels of skeletal muscle ${\alpha}$-actin mRNA during chronic administration of cimaterol, a ${\beta}$-adrenergic agonist. Cimaterol was mixed in a powdered rat diet at 10 mg/kg diet. At 3 and 21 days after the start of treatment, skeletal muscle and heart samples were collected for the measurement of cAMP concentrations and skeletal muscle ${\alpha}$-actin mRNA levels. Cimaterol increased (p < 0.01) body weight gain gradually during the first seven days of the trial period, but not thereafter. Most skeletal muscle weights and the ratio of muscle weight to body weight were increased (p < 0.05) by cimaterol treatment both at 3 and 21 days. Heart weight was also increased (p < 0.05) by cimaterol treatment at 3 and 21 days, but the ratio of heart weight to body weight was increased (p < 0.05) only at 3 day. Cimaterol decreased (p < 0.05) cAMP concentration of gastrocnemius muscle at both 3 and 21 days after treatment. However, cimaterol tended (p = 0.07) to increase cAMP concentration at 3 days in the heart. Cimaterol tended (p = 0.08) to increase the steady-state level of ${\alpha}$-actin mRNA by 60% in gastrocnemius muscle at 3 days but had no effect at 21 days. The results indicate that the pattern of hypertrophic response to chronic dietary administration of cimaterol is different between cardiac and skeletal muscle. In skeletal muscles it appears that the hypertrophy induced by cimaterol is partly due to stimulated myofibrillar protein synthesis at a pre-translational level.

Cloning and Characterization of Glycogen-Debranching Enzyme from Hyperthermophilic Archaeon Sulfolobus shibatae

  • Van, Trinh Thi Kim;Ryu, Soo-In;Lee, Kyung-Ju;Kim, Eun-Ju;Lee, Soo-Bok
    • Journal of Microbiology and Biotechnology
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    • 제17권5호
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    • pp.792-799
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    • 2007
  • A gene encoding a putative glycogen-debranching enzyme in Sulfolobus shibatae(abbreviated as SSGDE) was cloned and expressed in Escherichia coli. The recombinant enzyme was purified to homogeneity by heat treatment and Ni-NTA affinity chromatography. The recombinant SSGDE was extremely thermostable, with an optimal temperature at $85^{\circ}C$. The enzyme had an optimum pH of 5.5 and was highly stable from pH 4.5 to 6.5. The substrate specificity of SSGDE suggested that it possesses characteristics of both amylo-1,6-glucosidase and $\alpha$-1,4-glucanotransferase. SSGDE clearly hydrolyzed pullulan to maltotriose, and $6-O-\alpha-maltosyl-\beta-cyclodextrin(G2-\beta-CD)$ to maltose and $\beta$-cyclodextrin. At the same time, SSGDE transferred maltooligosyl residues to the maltooligosaccharides employed, and maltosyl residues to $G2-\beta-CD$. The enzyme preferentially hydrolyzed amylopectin, followed in a decreasing order by glycogen, pullulan, and amylose. Therefore, the present results suggest that the glycogen-debranching enzyme from S. shibatae may have industrial application for the efficient debranching and modification of starch to dextrins at a high temperature.