• 제목/요약/키워드: alpha type

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Saccharomyces cerevisiae를 이용한 온도조절형 발현 Vector의 개발 (Construction of a Temperature Controlled Expression Ve e tor in Saccharumy ces cerevisiae)

  • 최진옥;황용일
    • 한국미생물·생명공학회지
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    • 제21권3호
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    • pp.214-220
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    • 1993
  • The mating type a of yeast, Saccharomyces cerevisiae mutant with hmla2-102 and sir3-8ts was changed to type alpha by changing the growth temperature from 25C to 35C. A temperature-sensitive expression vector system was constructed using mating factor alpha1 (Mfalpha1) gene encoding alpha factor which is expressed in the type alpha cells. Vectors with different copy numbers were constructed by joining the promoter and pre or prepro-secretion single sequence of Mfalpha1 to promoterless PHO5' gene as a reporter gene.

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Utilization of Dried Garlic Powder and α-Tocopherol to Improve the Shelf-life of Emulsion-type Sausage during Refrigerated Storage

  • Kim, Young-Jik;Choi, In-Hag
    • 한국축산식품학회지
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    • 제32권6호
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    • pp.725-731
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    • 2012
  • This study investigated the shelf life of emulsion-type sausages containing garlic powder and/or ${\alpha}$-tocopherol during storage at $4^{\circ}C$ for 0, 10, 20, and 30 d. Six groups of emulsion-type sausages were included: control (no additives), GP1 (1% garlic powder), GP3 (3% garlic powder), AT100 (100 IU of ${\alpha}$-tocopherol/kg of sausage), AT200 (200 IU of ${\alpha}$-tocopherol/kg of sausage), and GP1+AT100 (1% garlic powder+100 IU of ${\alpha}$-tocopherol/kg of sausage). During storage, the pH, thiobarbituric acid reactive substances, and residual nitrite content were reduced by the addition of garlic powder and/or ${\alpha}$-tocopherol relative to the control (p<0.05). In addition, emulsion-type sausages supplemented with garlic powder and/or ${\alpha}$-tocopherol improved color stability (p<0.05). The results suggest that a higher amount of garlic powder and their different combinations could improve the shelf life of emulsion-type sausages and protect against lipid oxidation.

Expression of Low Voltage-Activated $Ca^{2+}$ Channels in Xenopus Oocytes

  • Lee, Jung-Ha;Han, Dong-Pyo
    • Journal of Microbiology and Biotechnology
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    • 제11권4호
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    • pp.614-618
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    • 2001
  • Low-threshold T-type $Ca^{2+}$ channels are distinctive voltage-operated gates for external $Ca^{2+}$ entry around a resting membrane potential due to their low voltage activation. These phenomena have already been extensively studied due to their relevance in diverse physiological functions. Recently, three T-type $Ca^{2+}$ channel ${\alpha}$$_1$subunits were cloned and their biophysical properties were characterized after expression in mammalian expression systems. In this study, ${\alpha_IG} and {\alpha_IH}$ low-threshold $Ca^{2+}$ channels were expressed and characterized in Xenopus oocytes after adding 5' and 3'untranslated portions of a Xenopus ${\beta}$ globin to improve their expression levels. The added portions dramatically enhanced the expression levels of the ${\alpha_IG} and {\alpha_IH}$ T-type channels. When currents were recorded in 10 mM $Ba^{2+}$ as the charge carrier, the activation thresholds were about -60 mV, peak currents appeared at -20 mV, and the reversal potentials were between +40 and +45. The activation time constants were very similar to each other, while the inactivation time constants of the ${\alpha_IG}$ currents were smaller than those of ${\alpha_IH}$. Taken together, the electrophysiological properties of the ${\alpha_IG} and {\alpha_IH}$ channels expressed in Xenopus oocytes were similar to the previously reported characteristics of low-threshold $Ca^{2+}$ channel currents.

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A note on Jensen type inequality for Choquet integrals

  • Jang, Lee-Chae
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제9권2호
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    • pp.71-75
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    • 2009
  • The purpose of this paper is to prove a Jensen type inequality for Choquet integrals with respect to a non-additive measure which was introduced by Choquet [1] and Sugeno [20]; $$\Phi((C)\;{\int}\;fd{\mu})\;{\leq}\;(C)\;\int\;\Phi(f)d{\mu},$$ where f is Choquet integrable, ${\Phi}\;:\;[0,\;\infty)\;\rightarrow\;[0,\;\infty)$ is convex, $\Phi(\alpha)\;\leq\;\alpha$ for all $\alpha\;{\in}\;[0,\;{\infty})$ and ${\mu}_f(\alpha)\;{\leq}\;{\mu}_{\Phi(f)}(\alpha)$ for all ${\alpha}\;{\in}\;[0,\;{\infty})$. Furthermore, we give some examples assuring both satisfaction and dissatisfaction of Jensen type inequality for the Choquet integral.

NMR structural studies on Human CD99 Type I

  • Kim, Hai-Young;Kim, Young-Mee;Joon Shin;Shin, Young-Kee;Park, Seong-Hoe;Lee, Weontae
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2003년도 정기총회 및 학술발표회
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    • pp.69-69
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    • 2003
  • Human CD99 is a ubiquitous 32-kDa transmembrane protein encoded by the mic2 gene. The major cellular functions of CD99 protein are related to homotypic cell adhension, apoptosis, vesicular protein transport, and differentiation of thymocytes or T cells. Recently it has been reported that expression of a splice variant of CD99 transmembrane protein (Type I and Type II) increases invasive ability of human breast cancer cells. To understand structural basis for cellular functions of CD99 (Type I), we have initiated studies on hCD99$^{TMcytoI}$ and hCD99$^{cytoI}$ using circular dichroism (CD) and multi-dimensional NMR spectroscopy. CD spectrum of hCD99$^{TMcytoI}$ in the presence of 200mM DPC and CHAPS displayed an existence $\alpha$-helical conformation. The solution structure of hCD99$^{cytoI}$ determined by NMR is composed of one N-terminal $\alpha$-helix, $\alpha$A, two C-terminal short $\alpha$-helix segments, $\alpha$B and $\alpha$C. While $\alpha$A and $\alpha$B are connected by the long flexible loop, $\alpha$B and $\alpha$C connected by type III$\beta$-turn. Although it has been rarely figured out the correlation between structure and functional mechanism of hCD99$^{TMcytoI}$ and hCD99$^{cytoI}$, there is possibility of dimerization or oligomerization. In addition, the feasible mechanism of hCD99$^{cytoI}$ is that it could have intramolecular interaction between the N- and C- terminal domain through large flexible AB loop.

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상아모세포의 I 형 아교질에 대한 부착 (THE ADHESION OF ODONTOBLAST TO TYPE I COLLAGEN)

  • 안명기;정태성;김신
    • 대한소아치과학회지
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    • 제37권3호
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    • pp.308-316
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    • 2010
  • 상아모세포는 부착분자들을 이용하여 기질에 부착하는 세포이며, 인테그린과 같은 부착분자들이 일련의 세포와 세포외기질을 인지하는 신호전달분자로 알려져 있다. 본 연구의 목적은 상아모세포(MDPC-23 세포)와 I형 아교질과의 상호작용과 TGF-${\beta}1$과 TNF-${\alpha}$가 세포부착분자의 발현에 미치는 영향을 알아보기 위해 시행하였다. 본 연구에서 MDPC-23 세포는 농도의존적으로 I형 아교질에 부착했으며, 면역형광염색법에서 MDPC-23 세포가 아교질에 부착할 때, 국소부착점에서 인테그린 ${\alpha}1$, ${\alpha}2$, CD44, FAK 그리고 paxillin의 발현양상을 관찰할 수 있었다. 싸이토카인 TGF-${\beta}1$은 MDPC-23 세포의 아교질에 대한 부착성 및 인테그린 ${\alpha}1$, ${\alpha}2$와 chondroitin sulfate의 발현을 증가시켰으며, RT-PCR의 결과에서는 인테그린 ${\alpha}1$의 mRNA의 양이 TGF-${\beta}1$에 의해서 증가되었음을 확인하였다. 결론적으로 MDPC-23 세포는 아교질에 부착 친화성을 갖고 있으며, 부착 시에 인테그린 ${\alpha}1$, ${\alpha}2$와 CD44 그리고 chondroitin sulfate와 같은 부착분자들이 관여한다. 그리고 TGF-${\beta}1$은 인테그린 ${\alpha}1$, ${\alpha}2$ 그리고 chondroitin sulfate와 같은 부착분자의 발현을 증가시켰다.

Weighted Geometric Means of Positive Operators

  • Izumino, Saichi;Nakamura, Noboru
    • Kyungpook Mathematical Journal
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    • 제50권2호
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    • pp.213-228
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    • 2010
  • A weighted version of the geometric mean of k ($\geq\;3$) positive invertible operators is given. For operators $A_1,{\ldots},A_k$ and for nonnegative numbers ${\alpha}_1,\ldots,{\alpha}_k$ such that $\sum_\limits_{i=1}^k\;\alpha_i=1$, we define weighted geometric means of two types, the first type by a direct construction through symmetrization procedure, and the second type by an indirect construction through the non-weighted (or uniformly weighted) geometric mean. Both of them reduce to $A_1^{\alpha_1}{\cdots}A_k^{{\alpha}_k}$ if $A_1,{\ldots},A_k$ commute with each other. The first type does not have the property of permutation invariance, but satisfies a weaker one with respect to permutation invariance. The second type has the property of permutation invariance. We also show a reverse inequality for the arithmetic-geometric mean inequality of the weighted version.

GENERALIZED VECTOR MINTY'S LEMMA

  • Lee, Byung-Soo
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제19권3호
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    • pp.281-288
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    • 2012
  • In this paper, the author defines a new generalized ${\eta}$, ${\delta}$, ${\alpha}$)-pseudomonotone mapping and considers the equivalence of Stampacchia-type vector variational-like inequality problems and Minty-type vector variational-like inequality problems for generalized (${\eta}$, ${\delta}$, ${\alpha}$)-pseudomonotone mappings in Banach spaces, called the generalized vector Minty's lemma.

GENERALIZED (α, β, γ) ORDER AND GENERALIZED (α, β, γ) TYPE ORIENTED SOME GROWTH PROPERTIES OF COMPOSITE ENTIRE AND MEROMORPHIC FUNCTIONS

  • Tanmay Biswas;Chinmay Biswas
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제31권2호
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    • pp.119-130
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    • 2024
  • In this paper we discuss on the growth properties of composite entire and meromorphic functions on the basis of generalized (α, β, γ) order and generalized (α, β, γ) type comparing to their corresponding left and right factors.

Rubus속 식물에 존재하는 $19{\alpha}-Hydroxyursane-type$ Triterpenoid의 특성과 이용 (Chemical Characterization and Utilization of $19{\alpha}-Hydroxyursane-type$ Triterpenoids in Rubus species)

  • 정현주;남정환;임상철;김원배;박희준
    • 한국자원식물학회지
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    • 제19권5호
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    • pp.563-572
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    • 2006
  • The plant Rubus species (Rosaceae) mainly contains $19{\alpha}-hydroxyurane-type$ triterpenoids $(19{\alpha}-HUT)$ as bioactive components. Available functional food includes blackberry (the fruit of thornless Rubus sp.), red raspberry (R. idaeus) and black raspberry (R. occidentalis). However, the fruit of R. coreanus, which is used in Korea as a functional food, substitutes black raspberry. Rubi Fructus, which has been traditionally used as an oriental medicinal drug, designates only unripe fruit of R. coreanus but not its ripe fruit which indicates that it needs high content of $19{\alpha}-HUT$ as a crude drug. Throughout our experiment, we found that ripe fruits contain very little amount of $19{\alpha}-HUT$ when compared to unripe fruits. In addition, various and rich $19{\alpha}-HUT$ has been reported from Rubus species. The most common structure of $19{\alpha}-HUT$ of Rubus species, euscaphic acid or tormentic acid with $3{\alpha}-OH$ or $3{\beta}-OH$, respectively, can be glycosylated or oxidized to produce a number of $19{\alpha}-HUTs $as euscaphic acid and tormentic acid derivatives and even esterified to form dimeric triterpenoids. In this review, the bioactivity and biosynthetic pathway and chemical characterization of $19{\alpha}-HUTs$ found in Rubus species are discussed.