• Title/Summary/Keyword: $\beta$-type

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Characteristics and Antibiotic Susceptibility of Imipenem-Resistant Clinical Isolates Producing Carbapenemase (Carbapenemase를 생산하는 imipenem 내성 세균의 특성 및 항생제 감수성)

  • Choe, Han-Na;Park, Chul;Kim, Hyung-Rak;Baik, Keun-Sik;Kim, Se-Na;Seong, Chi-Nam
    • Journal of Life Science
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    • v.20 no.8
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    • pp.1214-1220
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    • 2010
  • Imipenem-resistant bacteria were isolated from clinical specimens taken from hospitalized patients in Suncheon, Korea. Fifty-four isolates were phylogenetically analyzed based on 16S rRNA gene and gyrB gene sequence comparisons. Isolates were affiliated with Pseudomonas aeruginosa (30 strains; 55.6%), Acinetobacter baumannii (21; 38.9%), Enterobacter hormaechei (2) and Pseudomonas putida (2). Twenty-two isolates produced metallo-$\beta$-lactamase (MBL); 12 Acinetobacter baumannii strains, 7 Pseudomonas aeruginosa strains, 2 P. putida strains and 1 Enterobacter hormaechei strain. Antibiotic susceptibility of the isolates was determined using the disc diffusion method and Vitek system. Strains producing metallo-$\beta$-lactamase (type IMP & VIM) were more resistant to antibiotics ceftazidime, aztreonam, amikacin and gentamicin than to strains producing OXA and SHV type of $\beta$-lactamase.

Xylan Hydrolysis by Treatment with Endoxylanase and $\beta$-Xylosidase Expressed in Yeast

  • Heo, Sun-Yeon;Kim, Joong-Kyun;Kim, Young-Man;Nam, Soo-Wan
    • Journal of Microbiology and Biotechnology
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    • v.14 no.1
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    • pp.171-177
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    • 2004
  • The endoxylanase (642 bp; 213 amino acids) and $\beta$-xylosidase (1,602 bp; 533 amino acids) genes from Bacillus sp. were amplified by PCR and separately inserted into the downstream of the yeast ADH1 promoters, resulting in the pAEDX-1 (7.63 kb) and pAEX (8.47 kb) plasmids, respectively. When the yeast transformants, S. cerevisiae SEY2102 harboring pAEDX-1 or pAEX, were grown on YPD medium, the total activities of the enzymes were approximately 9.8 unit/ml for endoxylanase and 2.9 unit/m1 for $\beta$-xylosidase. When the three kinds of xylan from oat spelts, birch wood, and corncob were hydrolyzed by treating with recombinant endoxylanase and $\beta$-xylosidase, it was found that xylose, xylobiose, and xylotriose were produced. To efficiently hydrolyze xylan, various reaction conditions such as amount of enzymes, substrate type, substrate concentration, temperature, and reaction time were examined. The optimized conditions for the hydrolysis of xylan were as follows: amount of endoxylanase, 10 units; amount of $\beta$-xylosidase, 10 units; temperature, $50^\circ{C}$; substrate type, oat spelts xylan; substrate concentration, 6%; reaction time, 1 h. Under the optimal condition, xylose was mainly produced from oat spelts xylan by cooperative action of endoxylanase and $\beta$-xylosidase.

Hepatitis E Virus Papain-Like Cysteine Protease Inhibits Type I Interferon Induction by Down-Regulating Melanoma Differentiation-Associated Gene 5

  • Kim, Eunha;Myoung, Jinjong
    • Journal of Microbiology and Biotechnology
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    • v.28 no.11
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    • pp.1908-1915
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    • 2018
  • Upon viral infection, the host cell recognizes the invasion through a number of pattern recognition receptors. Melanoma differentiation associated gene 5 (MDA5) and retinoic acid-inducible gene-I (RIG-I) recognize RNA molecules derived from invading viruses, activating down-stream signaling cascades, culminating in the induction of the type I interferon. On the other hand, viruses have evolved to evade type I interferon-mediated inhibition. Hepatitis E virus has been shown to encode a few antagonists of type I interferon and it is not surprising that viruses encode multiple mechanisms of viral evasion. In the present study, we demonstrated that HEV PCP strongly down-regulates MDA5-mediated activation of interferon ${\beta}$ induction in a dose-dependent manner. Interestingly, MDA5 protein expression was almost completely abolished. In addition, polyinosinic polycytidylic acid (poly(I:C))- and Sendai virus-mediated activation of type I interferon responses were similarly abrogated in the presence of HEV PCP. Furthermore, HEV PCP down-regulates several molecules that play critical roles in the induction of type I IFN expression. Taken together, these data collectively suggest that HEV-encoded PCP is a strong antagonist of type I interferon.

STABILITY OF (α, β, γ)-DERIVATIONS ON LIE C*-ALGEBRA ASSOCIATED TO A PEXIDERIZED QUADRATIC TYPE FUNCTIONAL EQUATION

  • Eghbali, Nasrin;Hazrati, Somayeh
    • Communications of the Korean Mathematical Society
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    • v.31 no.1
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    • pp.101-113
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    • 2016
  • In this article, we considered the stability of the following (${\alpha}$, ${\beta}$, ${\gamma}$)-derivation $${\alpha}D[x,y]={\beta}[D(x),y]+{\gamma}[x,D(y)]$$ and homomorphisms associated to the quadratic type functional equation $$f(kx+y)+f(kx+{\sigma}(y))=2kg(x)+2g(y),\;x,y{\in}A$$, where ${\sigma}$ is an involution of the Lie $C^*$-algebra A and k is a fixed positive integer. The Hyers-Ulam stability on unbounded domains is also studied. Applications of the results for the asymptotic behavior of the generalized quadratic functional equation are provided.

NORMAL WEIGHTED BERGMAN TYPE OPERATORS ON MIXED NORM SPACES OVER THE BALL IN ℂn

  • Avetisyan, Karen L.;Petrosyan, Albert I.
    • Journal of the Korean Mathematical Society
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    • v.55 no.2
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    • pp.313-326
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    • 2018
  • The paper studies some new ${\mathbb{C}}^n$-generalizations of Bergman type operators introduced by Shields and Williams depending on a normal pair of weight functions. We find the values of parameter ${\beta}$ for which these operators are bounded on mixed norm spaces L(p, q, ${\beta}$) over the unit ball in ${\mathbb{C}}^n$. Moreover, these operators are bounded projections as well, and the images of L(p, q, ${\beta}$) under the projections are found.

A Numerical Analysis on Prediction of Cut-diameter according to Vane Outflow Angle in the Axial-flow Cyclone (축상유입식 사이클론의 베인 유출각도에 따른 절단입경 예측에 관한 수치해석)

  • Yi, Chung-Seob;Lee, Chi-Woo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.11 no.4
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    • pp.111-117
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    • 2012
  • Dust collecting performance of axial-vane type cyclone for oil mist was analyzed in this study. For predicting cut diameter size of cyclone, the number and angle of vane ($tan{{\beta}_2}^{\prime}$) was simulated by CFD. As the result, $tan{{\beta}_2}^{\prime}$ was decreased as the number of vane was increased and the angle of inclination(${{\beta}_2}^{\prime}$) decreased, and it cause strong swirl flow. Therefore, it could be confirmed that as the number of vane was increased and the angle of inclination was decreased, cut diameter size was decreased. Also, by verifying the results of CFD through experiment, the cut diameter size could be $2{\mu}m$ at $4m^3/min$ of flow rate.

Effects of Nurses' Resilience, Job Satisfaction, and Social Support on Organizational Commitment (간호사의 회복탄력성, 직무만족, 사회적 지지가 조직몰입에 미치는 영향)

  • Lee, Jeong-Sook
    • The Korean Journal of Health Service Management
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    • v.12 no.1
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    • pp.57-67
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    • 2018
  • Objectives : The purpose of this study was to examine the effect of nurses' resilience, job satisfaction, and social support on organizational commitment. Methods : The data were collected from August 25, 2017 to September 5, 2017 by distributing a questionnaire to 195 nurses. The measures in this study included resilience, job satisfaction, social support, and organizational commitment. The data were analyzed using descriptive statistics, t-tests, ANOVAs, Pearson's correlation coefficients, and a hierarchical multiple linear regression using the SPSS/WIN 21.0 program. Results : There were significant correlations among resilience, job satisfaction, social support, and organizational commitment. The factors that significantly influenced nurses' organizational commitment were job satisfaction (${\beta}=0.599$, p<.001), type of work (${\beta}=0.190$, p=.007), and pay satisfaction (${\beta}=0.170$, p=.002). Conclusions : In order to increase organizational commitment, it is necessary to create a systematic program that enhances nurses' job satisfaction with their type of work and pay satisfaction.

SYNTHESIS OF THE GINSENG GLYCOSIDES AND THEIR ANALOGS

  • Elyakov G. B.;Atopkina L. N.;Uvarova N. I.
    • Proceedings of the Ginseng society Conference
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    • 1993.09a
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    • pp.74-83
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    • 1993
  • In an attempt toward the synthesis of the difficulty accessible ginseng saponins the four dammarane glycosides identical to the natural $ginsenosides-Rh_2,$ - F2, compound K and chikusetsusaponin - LT8 have been prepared from betulafolienetriol(=dammar-24-ene-$3{\alpha},12{\beta}\;20(S)-triol).\;3-O-{\beta}-D-Glucopyranoside$ of 20(S) - protopanaxadiol $(=ginsenoside-Rh_2)$ have been obtained by the regio - and stereoselective glycosylation of the $12-O-acetyldammar-24-ene-3{\beta},\;12{\beta},$ 20(S)-triol. The 12-ketoderivative of 20(S)-protopanaxadiol has been used as aglycon in synthesis of chikusetsusaponin - LT8. Attempted regio - and stereoselective glycosylation of the less reactive tertiary C - 20 - hydroxyl group in order to synthesize the $20-O-{\beta}-D-glucopyranoside$ of 20(S)-protopanaxadiol(=compound K) using 3, 12 - di - O - acetyldammar - 24 - ene - $3{\beta},12{\beta},20(S)$-trial as aglycon was unsuccessful. Glycosylation of 3, 12 - diketone of betulafolienetriol followed by $NaBH_4$ reduction yielded the $20-O-{\beta}-D-glucopyranoside\;of\;dammar-24-ene-3{\beta},12{\alpha},$ 20(S)-triol, the $12{\alpha}-epimer$ of 20(S) - protopanaxadiol. Moreover, a number of semisynthetic ocotillol - type glucosides, analogs of natural pseudoginsenosides, have been prepared.

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Inclusion Complex of Analgesic and Antiinflammatory agents with Cyclodextrins (I): Enhancement of Dissolution of Ibuprofen by $2-Hydroxypropyl-{\beta}-cyclodextrin$ (시클로덱스트린과 소염진통제 간의 포접복합체에 관한 연구(I): 2-히드록시프로필-${\beta}$-시클로덱스트린에 의한 이부프로펜의 용출 증가)

  • Oh, In-Joon;Park, Jeong-Gyu;Lee, Yong-Bok;Shin, Sang-Chul
    • Journal of Pharmaceutical Investigation
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    • v.23 no.1
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    • pp.11-18
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    • 1993
  • Inclusion complex of ibuprofen with $2-Hydroxypropyl-{\beta}-cyclodextrin\;(HP-{\beta}-CD)$ in aqueous solution and in the solid state was evaluated by the solubility method and the instrumental analysis such as infrared spectroscopy, thermal analysis and x-ray diffractometry. The aqueous solubility of ibuprofen was increased linearly with the increase in the concentration of $HP-{\beta}-CD$, showing an $A_L$ type phase solubility diagram. The results showed that the dissolution rate of ibuprofen was significantly increased by complexation with $HP-{\beta}-CD$. $Ibuprofen-HP-{\beta}-CD$ complex enhanced the mean plasma concentration levels and the area under plasma concentration-time curve after oral administration compared to those of the drug alone. It is concluded that the complex of ibuprofen with $HP-{\beta}-CD$ increases the dissolution rate and improves the bioavailability of the ibuprofen by the formation of a water-soluble complex.

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Fermentation Kinetics for Production of Carotenoids by ${\beta}$-ionone Resistant Mutant of Xanthophyllomyces dendrorhous (Xanthophyllomyces dendrorhous 변이군주에 의한 Carotenoids 생산 발효의 특성 연구)

  • Park, Ki-Moon;Kim, Young-Jun;Song, Min-Woo;Kang, Seog-Jin;Lee, Jae-Heung
    • KSBB Journal
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    • v.21 no.4
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    • pp.286-291
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    • 2006
  • Various ${\beta}$-ionone resistant mutants were isolated from the wild-type red yeast Xanthophyllomyces dendrorhous KCTC 7704. Although the growth of X. dendrorhous KCTC 7704 was strongly inhibited at 0.025 mM ${\beta}$-ionone, one of the ${\beta}$-ionone resistant mutants isolated at 0.1 mM ${\beta}$-ionone by NTG mutagenesis showed rather 70% of relative survival at 0.15 mM ${\beta}$-ionone. Fermentation kinetics study with the mutant was carried out at $20^{\circ}C$ for 4 days in 300-mL baffled flasks. The mutant yielded up to 2.3-fold higher carotenoids content(viz. $1.2{\mu}g$ of total carotenoids per mg of dry cells) compared with the wild-type strain. The production of metabolites such as organic acids could be neglected. Studies on the kinetics with various carbon substrates revealed both an increase in final dry cell mass and a higher total carotenoids content in cell mass with glucose when compared to fructose or sucrose. As a further part of study, the effect of pH on the fermentation kinetics was investigated in glucose-limited chemostat at a dilution rate of $0.04h^{-1}$. When compared to steady-state kinetic parameters obtained at pH 4.0, a significant reduction in cell concentration at pH 3.0 and a lower carotenoids content at pH 5.2 were evident.