• 제목/요약/키워드: {\beta}$

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떡버들 잎의 플라보노이드 (Flavonoids from Salix hallaisanensis Leaves)

  • 오미현;함인혜;정성희;황완균
    • 생약학회지
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    • 제36권4호통권143호
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    • pp.282-290
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    • 2005
  • The MeOH extract of the the leaves of Salix hallaisanensis (Salicaceae) was partitioned successively with $CHCl_3$, 20% MeOH, 40% MeOH and 60% MeOH solution. From the fractions obtained, 9 compounds were isolated, $diosmetin-7-O-{\beta}-d-glucoside$ (I), $diosmetin-7-O-{\beta}-D-glucosyl-(1{\rightarrow)6)-{\beta}-d-glucoside$ (II), $diosmetin-7-O-{\beta}-d-xylosyl-(1{\rightarrow}6)-{\beta}-D-glucoside$ (III), $quercetin-3-O-{\beta}-d-galactoside$ (hyperoside) (IV), $quercetin-3-O-{\alpha}-l-rhamnosyl-(1{\rightarrow}6)-{\beta}-D-glucoside(rutin)$ (V), luteolin (VI), $luteolin-7-O-{\beta}-d-glucoside$ (VII), $kaempferol-3-O-{\alpha}-l-rhamnosyl-(1{\rightarrow}6)-{\beta}-D-glucoside$ (VIII), and (+)-catechin (IX).

Optimization of Cholesterol Removal by Crosslinked ${\beta}$-Cyclodextrin in Egg Yolk

  • Jung, Tae-Hee;Park, Heung-Sik;Kwak, Hae-Soo
    • Food Science and Biotechnology
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    • 제14권6호
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    • pp.793-797
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    • 2005
  • Optimum conditions for cholesterol removal in egg yolk were evaluated based on ratio of egg yolk-to-water, crosslinked ${\beta}$-cyclodextrin (${\beta}$-CD) concentration, and mixing temperature, time, and speed by adding crosslinked ${\beta}$-CD treated with adipic acid. Cholesterol removal in egg yolk-water mixture increased with increasing ${\beta}$-CD level (10-25%). About 95% was removed by 25% ${\beta}$-CD at 1:1 ratio of egg yolk-to-water and 800 rpm mixing at $40^{\circ}C$ for 30 min. In recycling study, removal rates were measured using ten times recycled crosslinked ${\beta}$-CD in egg yolk, and 85% cholesterol removal was observed with eight times reuse. These results indicated that over 90% cholesterol was removed at 1:1 ratio of egg yolk-to-water, 20% crosslinked ${\beta}$-CD addition, and 30 min mixing with 600 rpm at $40^{\circ}C$.

Functional Effects of $\beta4$-Subunit on Rat $BK_{Ca}$ Channel $\alpha$-Subunit, rSlo

  • Ha, Tal-Soo;Heo, Moon-Sun;Park, Chul-Seung
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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    • pp.32-32
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    • 2002
  • To understand the functional roles of the neuron-specific $\beta$-subunit of large-conductance calcium-activated potassium ($BK_{Ca}$) channel, we isolate the full-length complementary DNA of $\beta$4-subunit from rat brain library and investigated its effects on the function of $\alpha$-subunit (Slo). The deduced amino acid sequence of rat $\beta$4 (r$\beta$4), 210 amino acids in length, was closely related to those of $\beta$4 subunits in other mammalian species but showed only a limited sequence homology to the other $\beta$-subunits, $\beta$1 to $\beta$3.(omitted)d)

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베타 락탐계 항생제의 합성 및 항균력 (Synthesis of $\beta$-Lactam Antibiotics and Their Antibacterial Activity)

  • 홍석기;남재우;이경태;신관석
    • 약학회지
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    • 제37권2호
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    • pp.158-162
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    • 1993
  • 6$\beta$-(trans-3-Aryl-5-oxo-pyrrolidin-2-yl)acetamidopenicillanic acid(7a~7c) and 7$\beta$-(trans-3-Aryl-5-oxo-pyrrolidin-2-yl) acetamidocephalosporanic acid(8a~8c) were synthesized and tested in vitro antibacterial activity. Of these new penicillins exhibited good antibacterial activity against Gram-positive bacteria whereas none of the compounds possessed the activity against Gram-negative bacteria at the concentration tested.

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모세관 전기영동법을 이용한 베타차단제-시클로덱스트린 포접화합물의 안정도상수 결정 (Determination of Stability Constants for $\beta$-Blocker and Carboxymethyl-$\beta$-cyclodextrin Complexes by Capillary Electrophoresis)

  • 박경래;임환미;뉴엔티퐁;김경호;강종성
    • 약학회지
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    • 제47권4호
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    • pp.200-205
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    • 2003
  • The stability constants for the inclusion complexes between carboxymethyl-$\beta$-cyclodextrin (CM-$\beta$-CD) and five $\beta$-blockers, such as atenolol (ATE), bisoprolol (BIS), metoprolol (MET), pindolol (PIN) and propranolol (PRO) were determined by capillary electrophoresis. The magnitude of stability was decreased as following order; PRO>MET>BIS>ATE>PIN. Among them PRO showed the highest affinity towards CM-$\beta$-CD with stability constants of 383 and 371 $M^{-l}$ for (R)- and (S)-enantiomer, respectively. PIN enantiomers showed the lowest stability towards CM-$\beta$-CD, while the selectivity between (R)- and (S)-enantiomer was higher than any other tested $\beta$-blocker.r.

ON SOME NEW CLASSES OF COMPACT-LIKE BITOPOLOGICAL SPACES

  • Afsan, BM Uzzal
    • 충청수학회지
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    • 제33권2호
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    • pp.271-285
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    • 2020
  • In this paper, we have introduced a new type of covering property ${\beta}^t_{({\omega}_r,s)}$-closedness, stronger than $P^t_{({\omega}_r,s)}$-closedness [3] in terms of (r, s)-β-open sets [9] and β-ωt-closures in bitopological spaces along with its several characterizations via filter bases and grills [15] and various properties. Further grill generalizations of ${\beta}^t_{({\omega}_r,s)}$-closedness (namely, ${\beta}^t_{({\omega}_r,s)}$-closedness modulo grill) and associated concepts have also been investigated.

$\beta$-carboline alkaloids of polygala tenuifolia

  • Han, Byung-Hoon;Park, Jeong-Hill;Park, Myung-Hwan;Han, Yong-Nam
    • Archives of Pharmacal Research
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    • 제8권4호
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    • pp.243-247
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    • 1985
  • A new $\beta$-carboline alkaloid, 1-carbobutoxy-$\beta$-carboline as well as $N_{9}$ -formylharman, 1-carboethoxy-$\beta$-carboline, 1-carbomethoxy-$\beta$- carboline, perloyrine, harman and norharman were isolated from the rhizoma of Polygala tenuifolia Willdenow. The structures were elucidated on the basis of spectroscopic studies and chemical evidence.

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BETA-EXPANSIONS WITH PISOT BASES OVER Fq((x-1))

  • Hbaib, Mohamed
    • 대한수학회보
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    • 제49권1호
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    • pp.127-133
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    • 2012
  • It is well known that if the ${\beta}$-expansion of any nonnegative integer is finite, then ${\beta}$ is a Pisot or Salem number. We prove here that $\mathbb{F}_q((x^{-1}))$, the ${\beta}$-expansion of the polynomial part of ${\beta}$ is finite if and only if ${\beta}$ is a Pisot series. Consequently we give an other proof of Scheiche theorem about finiteness property in $\mathbb{F}_q((x^{-1}))$. Finally we show that if the base ${\beta}$ is a Pisot series, then there is a bound of the length of the fractional part of ${\beta}$-expansion of any polynomial P in $\mathbb{F}_q[x]$.

Mechanism and Products During the Homolytic Addition of CCl$_4$ and Cl$_3$CBr to $\beta$-Halostyrenes

  • Kim Sung-Soo
    • Bulletin of the Korean Chemical Society
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    • 제1권2호
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    • pp.45-49
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    • 1980
  • During the homolytic reactions of $CCl_4$ or $Cl_3CBr with ${\beta}-halo^1$-styrenes,$\beta$-haloradicals are key intermediates. They are to be stabilized via three pathways; $\beta$-cleavage, halogen transfer and telomerization. The three reaction paths are delicately controlled by the energetics of their formation and stabilization. When the formation of a $\beta$-haloradical is accompanied by considerable excess of energy from an exothermic reaction, $\beta$ -cleavage is often dominant over the halogen transfer. On the other hand, if the radical forms via a reversible reaction, two processes become competitive. $\beta$-Eliminated bromine atoms from ${\beta}$ -bromoradicals generate $Br_2$ via $Cl_3CBr + {\cdot}Br {\leftrightarrow} Br_2 + {CCl_3}{\cdot}{Br_2}$ may act as a better scavenger than Cl3CBr for the ${\beta}$-bromoradicals. Different reactivities of chlorine, bromine and trichloromethyl radicals towards olefinic pi-bond are clarified in terms of the beat content of the addition reactions.

Crosstalk Signaling between IFN-γ and TGF-β in Microglia Restores the Defective β-amyloid Clearance Pathway in Aging Mice with Alzheimer's Disease

  • Choi, Go-Eun
    • 대한의생명과학회지
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    • 제24권4호
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    • pp.305-310
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    • 2018
  • Microglia are emerging as critical regulators of innate immune responses in AD and other neurodegenerative disorders, highlighting the importance of understanding their molecular and cellular mechanisms. We attempted to determine the role of crosstalk signaling between $IFN-{\gamma}$ and $TGF-{\beta}$ in $A{\beta}$ clearance by microglia cells. We used in vitro and in vivo mouse models that recapitulated acute and chronic aspects of microglial responses to $A{\beta}$ peptides. We showed that crosstalk signaling between $TGF-{\beta}$ and Smad2 was an important mediator of neuro-inflammation. These findings suggest that microglial $TGF-{\beta}$ activity enhances the pathological progression to AD. As $TGF-{\beta}$ displays broad regulatory effects on beneficial microglial functions, the activation of inflammatory crosstalk signaling between $TGF-{\beta}$ and Smad2 may be a promising strategy to restore microglial functions, halt the progression of $A{\beta}$-driven pathology, and prevent AD development.