• Title/Summary/Keyword: $A{\beta}$

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Synergistic effects of dietary $\beta$-1,3 glucan and feed stimulants in juvenile olive flounder (Paralichthys olivaceus)

  • Sungchul C. Bai;Park, Gunjun;Kim, Joon-Hyung;Cui Hua;Kim, Youngchul
    • Proceedings of the Korean Aquaculture Society Conference
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    • 2003.10a
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    • pp.68-69
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    • 2003
  • The present study was conducted to investigate the effects of dietary supplementation of $\beta$-1,3 glucan and feed stimulants(BAISM) as a feed additive for juvenile olive flounder (Paralichthys olivaceus). Eight experimental diets supplemented with $\beta$-1,3 glucan and feed stimulants at 0%, $\beta$-1,3 glucan 0.05% + Baism 0.45%, $\beta$-1,3 glucan 0.05% + Baism 0.95%, $\beta$-1,3 glucan 0.10% + Baism 0.90%, $\beta$-1,3 glucan 0.10% + Baism 1.90%, $\beta$-1,3 glucan 0.15% + Baism 1.35%, $\beta$-1,3 glucan 0.15% + Baism 2.85% and $\beta$-1,3 glucan 0.30% + Baism 2.70% of diets as a dry-matter(DM) basis were prepared. Three replicate groups of fish averaging 9.2 $\pm$ 0.1g (Mean $\pm$ SD) were randomly distributed in each aquarium as a group of 15 fish and fed one of eight experimental diets for seven weeks. After the feeding trial, $\beta$-1,3 glucan 0.10% + Baism 0.90%, $\beta$-1,3 glucan 0.10% + Baism 1.90% diets had a higher weight gain (WG), feed efficiency(FE), specific growth rate(SGR) and protein efficiency ratio(PER) than did fish fed 0%, $\beta$-1,3 glucan 0.05% + Baism 0.45%, $\beta$-1,3 glucan 0.05% + Baism 0.95%, $\beta$-1,3 glucan 0.15% + Baism 2.85% and $\beta$-1,3 glucan 0.30% + Baism 2.70% (P<0.05). however, there was no significant difference among fish fed $\beta$-1,3 glucan 0.05% + Baism 0.45%, $\beta$-1,3 glucan 0.05% + Baism 0.95%, $\beta$-1,3 glucan 0.15% + Baism 2.85% and $\beta$-1,3 glucan 0.30% + Baism 2.70%(P>0.05). and $\beta$-1,3 glucan 0.10% + Baism 0.90% diets had a higher peak value of CL(Chemiluminescence) and lysozyme activity, than did fish fed the other diets (P<0.05). These results indicated that dietary sipplementation of $\beta$-1, 3 glucan and Baism affected growth, feed efficiency, specific growth rate, protein efficiency ratio, Peak value of CL and Lysozyme activity, and the optimum dietary supplementation level of $\beta$-1, 3 glucan and Baism as a feed additive could be approximately $\beta$-1, 3 glucan 0.10% + Baism 0.90% of diet in juvenile olive flounder (Paralichthys olivaceus).

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Enhancement of radiation effect using beta-lapachone and underlying mechanism

  • Ahn, Ki Jung;Lee, Hyung Sik;Bai, Se Kyung;Song, Chang Won
    • Radiation Oncology Journal
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    • v.31 no.2
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    • pp.57-65
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    • 2013
  • Beta-lapachone (${\beta}$-Lap; 3,4-dihydro-2, 2-dimethyl-2H-naphthol[1, 2-b]pyran-5,6-dione) is a novel anti-cancer drug under phase I/II clinical trials. ${\beta}$-Lap has been demonstrated to cause apoptotic and necrotic death in a variety of human cancer cells in vitro and in vivo. The mechanisms underlying the ${\beta}$-Lap toxicity against cancer cells has been controversial. The most recent view is that ${\beta}$-Lap, which is a quinone compound, undergoes two-electron reduction to hydroquinone form utilizing NAD(P)H or NADH as electron source. This two-electron reduction of ${\beta}$-Lap is mediated by NAD(P)H:quinone oxidoreductase (NQO1), which is known to mediate the reduction of many quinone compounds. The hydroquinone forms of ${\beta}$-Lap then spontaneously oxidizes back to the original oxidized ${\beta}$-Lap, creating futile cycling between the oxidized and reduced forms of ${\beta}$-Lap. It is proposed that the futile recycling between oxidized and reduced forms of ${\beta}$-Lap leads to two distinct cell death pathways. First one is that the two-electron reduced ${\beta}$-Lap is converted first to one-electron reduced ${\beta}$-Lap, i.e., semiquinone ${\beta}$-Lap $(SQ)^{{\cdot}-}$ causing production of reactive oxygen species (ROS), which then causes apoptotic cell death. The second mechanism is that severe depletion of NAD(P)H and NADH as a result of futile cycling between the quinone and hydroquinone forms of ${\beta}$-Lap causes severe disturbance in cellular metabolism leading to apoptosis and necrosis. The relative importance of the aforementioned two mechanisms, i.e., generation of ROS or depletion of NAD(P)H/NADH, may vary depending on cell type and environment. Importantly, the NQO1 level in cancer cells has been found to be higher than that in normal cells indicating that ${\beta}$-Lap may be preferentially toxic to cancer cells relative to non-cancer cells. The cellular level of NQO1 has been found to be significantly increased by divergent physical and chemical stresses including ionizing radiation. Recent reports clearly demonstrated that ${\beta}$-Lap and ionizing radiation kill cancer cells in a synergistic manner. Indications are that irradiation of cancer cells causes long-lasting elevation of NQO1, thereby sensitizing the cells to ${\beta}$-Lap. In addition, ${\beta}$-Lap has been shown to inhibit the repair of sublethal radiation damage. Treating experimental tumors growing in the legs of mice with irradiation and intraperitoneal injection of ${\beta}$-Lap suppressed the growth of the tumors in a manner more than additive. Collectively, ${\beta}$-Lap is a potentially useful anti-cancer drug, particularly in combination with radiotherapy.

NILPOTENCY CLASSES OF RIGHT NILPOTENT CONGRUENCES

  • Jeong, Joo-Hee
    • Bulletin of the Korean Mathematical Society
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    • v.36 no.1
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    • pp.139-146
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    • 1999
  • It is known that a right nilpotent congruence $\beta$ on a finite algebra A is also left nilpotent [3]. The question on whether the left nilpotency class of $\beta$ in less than or equal to the right nilpotency class of $\beta$is still open. In this paper we find an upper limit for the left nilpotency class of $\beta$. In addition, under the assumption that 1 $\in$ typ{A}, we show that $(\beta]^k=[\beta)^k$ for all k$\geq$1. Thus the left and right nilpotency classes of $\beta$ are the same in this case.

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ON BRAID-PLAT RELATIONS IN CONWAY FUNCTION

  • Yun, Ki-Heon
    • Honam Mathematical Journal
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    • v.33 no.3
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    • pp.407-418
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    • 2011
  • There are two kinds of closing method for a given braid ${\beta}{\in}B_{2n}$, a braid closure $\hat{\beta}$ and a plat closure $\bar{\beta}$. In the article, we find a relation between the Conway potential function ${\nabla}_{\hat{\beta}}$ of braid closure $\hat{\beta}$ and ${\nabla}_{\hat{\beta}}$ of plat closure $\bar{\beta}$.

Mercury induced the Accumulation of Amyloid Beta (Aβ) in PC12 Cells: The Role of Production and Degradation of Aβ

  • Song, Ji-Won;Choi, Byung-Sun
    • Toxicological Research
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    • v.29 no.4
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    • pp.235-240
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    • 2013
  • Extracellular accumulation of amyloid beta protein ($A{\beta}$) plays a central role in Alzheimer's disease (AD). Some metals, such as copper, lead, and aluminum can affect the $A{\beta}$ accumulation in the brain. However, the effect of mercury on $A{\beta}$ accumulation in the brain is not clear. Thus, this study was proposed to estimate whether mercury concentration affects $A{\beta}$ accumulation in PC12 cells. We treated 10, 100, and 1000 nM $HgCl_2$ (Hg) or $CH_3HgCl_2$ (MeHg) for 48 hr in PC12 cells. After treatment, $A{\beta}_{40}$ in culture medium increased in a dose- and time-dependent manner. Hg and MeHg increased amyloid precursor protein (APP), which is related to $A{\beta}$ production. Neprilysin (NEP) levels in PC12 cells were decreased by Hg and MeHg treatment. These results suggested that Hg induced $A{\beta}$ accumulation through APP overproduction and reduction of NEP.

Effect of Mycelial Extract of Clavicorona pyxidata on the Production of Amyloid $\beta$-Peptide and the Inhibition of Endogenous $\beta$-Secretase Activity in vitro

  • Lee, Tae-Hee;Park, Young-Il;Han, Yeong-Hwan
    • Journal of Microbiology
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    • v.44 no.6
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    • pp.665-670
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    • 2006
  • Amyloid $\beta$-peptide (A$\beta$), which is a product of the proteolytic effect of $\beta$-secretase (BACE) on an amyloid precursor protein, is closely associated with Alzheimer's disease (AD) pathogenesis. There is sufficient evidence to suggest that a BACE inhibitor may reduce A$\beta$ levels, thus decreasing the risk of AD. In a previous study, an extract of Clavicorona pyxidata DGUM 29005 mycelia was found to inhibit the production of a soluble $\beta$-amyloid precursor protein (s$\beta$APP), A$\beta$, and BACE in neuronal cell lines. We sought to determine whether this mycelial extract exerts the same effect in human rhabdomyosarcoma A-204 and rat pheochromocytoma PC-12 cells. We found that the production of A$\beta$ decreased in a dose-dependent manner in the presence of the mycelial extract and that the concentration of A$\beta$ never exceeded $50{\mu}g/ml$. The presence of sAPP was detected in every culture medium to which the mycelial extract had been added and its concentration remained the same, regardless of the concentration of the extract used. Endogenous $\beta$-secretase activity in A-204 and PC-12 cellular homogenates also decreased in the presence of this extract. These cells, in culture, were not susceptible to the cytotoxic activity of the mycelial extract.

Characterization of the \beta-Galactosidase Produced by Streptomyces sp. YB-10 (\beta-Galactosidase를 생산하는 Streptomyces sp. YB-10의 분리 및 효소 특성)

  • 윤기홍;이경섭;김창진
    • Microbiology and Biotechnology Letters
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    • v.31 no.2
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    • pp.151-156
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    • 2003
  • A strain YB-10 was isolated from soil as a producer of the extracellular $\beta$-D-galactosidase, which catalyzes the hydrolysis of lactose. The strain YB-10 was identified as Streptomyces sp. on the basis of its cultural, morphological and physiological properties. After treating culture supernatant of the isolate with ammonium sulfate, the precipitated protein was used as a crude $\beta$-galactosidase for analyzing its reaction properties with para-nitrophenyl-$\beta$-D-galactosidase(pNP-$\beta$Gal) as a substrate. The $\beta$-galactosidase showed its maximal activity at pH 6.0 and 6$0^{\circ}C$. The enzyme was also active on lactose. The hydrolyzing activity of $\beta$-galactosldase for pNP-$\beta$Gal and lactose was decreased by galactose. Its hydrolyzing activity far lactose was also decreased by glucose, but the activity for pNP-$\beta$Gal was increased to 1.8-folds by glucose.

Isolation and identification of $\beta$-glucan degrading enzyme producing bacterium using coloured $\beta$-glucan (색소에 접합된 $\beta$-glucan을 이용한 $\beta$-glucan 분해효소 생산 균주의 분리 및 동정)

  • 양진오;정안식;이성택
    • Korean Journal of Microbiology
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    • v.25 no.4
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    • pp.339-345
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    • 1987
  • A bacterium K-4-3, producing $\beta$-glucan hydrolyzing enzyme, was isolated from soil and identified to be Bacillus subtilis by its morpholohical and physiological characteristics. $\beta$-glucan was coloured using cibacron blue 3G-A and cross linded by the addition of 1, 4-butanedioldiglycidyl ether. This substrate was used for the isolation of $\beta$-glucanase producing microorganism. The $\beta$-glucan hydrolyzing enzyme actibity from isolated K-4-3 strain was also measured using the modified substrate. Bacillus subtilis K-4-3 produced the highest extracellular $\beta$-glucan hydrolyzing activity in the basal medium containing $\beta$-glucan as a carbon source, peptone and tryptone as a nitrogen source, and magnesium sulfate as an inorganic salt. The optimum temperature and initial pH for $\beta$-glucanase production by Bacillus subtilis K-4-3 were $37^{\circ}C$ and pH6. The highest enzyme activity was obtained at the culture age of 54 hrs with rotary shaking at $37^{\circ}C$. The crude enzyme showed the highest activity at pH 7.5-8.0 and $65^{\circ}C$.

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ON FUZZY ${\beta}-COMPACT^*$ SPACES AND FUZZY $\beta$-FILTERS

  • Uma, M.K.;Roja, E.;Balasubramanian, G.
    • East Asian mathematical journal
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    • v.23 no.2
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    • pp.151-158
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    • 2007
  • In this paper we introduce the concept of fuzzy ${\beta}-compact^*$ spaces. Besides giving some interesting properties of fuzzy ${\beta}-compact^*$ spaces we also give a characterization on fuzzy $\beta$-compact spaces by making use of newly introduced concept of fuzzy $\beta$-filters.

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Streptococcus LJ-22, a human intestinal bacterium, transformed glycyrrhizin to 18$\beta$-glycyrrhetinic acid monoglucuronide

  • Kim, Dong-Hyun;Lee, Seoung-Won;Park, Hae-Young;Han, Myung-Joo
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.125-125
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    • 1998
  • Glycyrrhizin (18$\beta$-glycyrrhetic acid $\beta$-D-glucuronyl a-D-glucuronic acid, GL), a main component of liquore extract (Glycyrrhiza glabra), is ingested orally as a component in the oriental medicine. By human intestinal bacteria, glycyrrhizin (18$\beta$-glycyrrhetinic acid $\beta$-D-glucuronyl a-D-glucuronic acid, GL) was metabolized to glycyrrhetinic acid (GA): main pathway metabolizing GL to GA by glucuronidases of Bacteroides J-37 (Kim et al., 1997) and Eubacterium sp strain GLH (Akao et al., 1987) and minor pathway metabolizing GL to GA via 18$\beta$-glycyrrhetic acid D-glucuronic acid (GAMG) by $\beta$-glucuronidase of Streptococcus LJ-22 and glucuronidases of Bacteroides J-37 / E. coli. $\beta$-Glucuronidase from Streptococcus LJ-22 hydrolyzed GL to GAMG, not GA. $\beta$-Glucuronidase of Streptococcus LJ-22 hydrolyzed $\beta$-glucuronic acid conjugates of polysaccharides rather than aglycone-$\beta$-glucuronides Optimal pH of Streptococcus LJ-22 $\beta$-glucuronidase was 5-6 and its molecular weight was 250 kDaltons. Km for GL was 0.37mM.

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