• 제목/요약/키워드: ${\beta}-transformation$

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Capsaicinoids의 미생물전환 메카니즘 (Micerobial Transformation Mechanism of Capsaicinoids)

  • 이익수;이상섭
    • 약학회지
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    • 제31권5호
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    • pp.280-285
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    • 1987
  • There are three plausible bioconversion pathways in biodegradation mechanism of capsaicinoids; first, side chain degradation through $\omega$-hydroxylation and $\beta$-oxidation, secondly, aromatic ring hydroxylation, and lastly, hydrolysis on the acidaraide linkage. In microbes, it was reported that capsaicin and its synthetic, analog, nonoylvanillylamide(NVA), could be metabolized to N-vanillylcarbamoylbutyric acid via $\omega$-hydroxylation and consecutive $\beta$-oxidations by Aspergillus niger. In order to broaden the scope of microbial degradation of capsaicinoids, over thirty strains of various fungi including Aspergillus, Penicillum, Mycotypha, Gliocladium, Paecilomyces, Byssoclamys, Conidiobolus, Thamnidium, and Entomophthora. It was observed that almost all the strains examined oxidized, the side chain of capsaicids as A. niger did. These observations strongly support the notion that side chain degradation is the most dominant pathway in the microbial degradation of capsaicinoids.

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On Extended Hurwitz-Lerch Zeta Function

  • Mohannad Jamal Said Shahwan;Maged Gumman Bin-Saad;Mohammed Ahmed Pathan
    • Kyungpook Mathematical Journal
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    • 제63권3호
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    • pp.485-506
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    • 2023
  • This paper investigates an extended form Hurwitz-Lerch zeta function, as well as related integral images, ordinary and fractional derivatives, and series expansions, using the term extended beta function. We establish a connection between the extended Hurwitz-Lerch zeta function and the Laguerre polynomials. Furthermore, we present a probability distribution application of the extended Hurwitz-Lerch zeta function ζ𝛿,𝜇𝜈,λ. Several results, both known and new, are shown to follow as special cases of our findings.

인체 상피세포에서 ras-종양유전자의 발암화가 신호 전달 기작에 미치는 영향 (EFFECTS OF SIGNAL TRANSDUCTION PATHWAY IN THE RAS-INDUCED CELLULAR TRANSFORMATION OF HUMAN EPITHELIAL CELLS IN CULTURE)

  • 장도근;변기정;김진수
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제26권3호
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    • pp.254-261
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    • 2000
  • 본 연구는 인체암 발생과 밀접한 관련을 가지고 있는 ras 종양 유전자의 발암화기전을 인체상피세포모델을 이용하여 규명하고자 SV40-Ad12 hybrid virus에 의해 불멸화된 인체상피세포모델에 H-ras 종양유전자을 함유하는 $pSV_2-ras$를 transfection하여 H-ras에 의한 세포발암화를 평가하였다. ras를 함유하는 세포군은 대조세포군에 비해 saturation density, soft-agar colony formation, cell aggregation 등의 세포 발암화지표가 유의한 수준으로 높게 나타나 H-ras에 의한 인체상피세포의 발암화를 확인하였다. 또한 H-ras에 의한 인체세포 발암화는 hydrocortisone과 같은 glucocorticoid에 의해 촉진되어 saturation density, soft-agar colony formation의 증가 및 foci의 출현시기의 단축을 나타내었다. H-ras 종양 유전자에 의한 인체세포발암화 과정에 관여하는 신호전달기작의 영향을 평가하기 위해 효현제 처리 후 세포내 칼슘농도변화를 측정한 결과 발암세포의 세포내 칼슘농도변화가 낮게 나타났으며 특히 이러한 반응차이는 세포외 칼슘의 존재하에서 더욱 뚜렷이 나타났다. 따라서 세포외부로부터 칼슘의 세포내 이동이 발암화에 의해 억제되고 있음을 보였다. 또한 효현제 처리후 $IP_3$ 농도의 변화를 측정한 결과 발암세포의 $IP_3$ 증가폭이 대조군 세포보다 훨씬 낮았다. 이러한 결과는 H-ras에 의한 세포 발암화에 phospholipase C와 관련한 신호전달기작의 down-regulation이 관여하고 있음을 보여주고 있다. 성장조절인자의 mRNA 발현을 평가한 결과 $TGF-{\beta}_1$ 및 PAI-2의 발현은 발암세포에서 낮게 나타난 반면 fibronectin의 경우는 발암세포의 발현이 높게 나타났다. 이러한 결과는 H-ras 종양유전자에 의한 발암화 과정에 성장조절인자의 변화가 관여하고 있으며 이러한 성장조절인자의 확인은 암발생의 생물학적 지표를 선별하는 데 기여할 것으로 사료된다. 본 연구는 H-ras 종양유전자에 의한 인체세포 발암화의 확인과 발암화 과정에 관여하는 신호전달기작의 변화 및 성장조절인자의 확인을 통하여 상피세포에서 나타나는 구강암 등의 발생기전 이해 뿐만 아니라 생체지표의 개발에 필요한 기초자료를 마련하는 데 기여할 것으로 사료된다.

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FURTHER HYPERGEOMETRIC IDENTITIES DEDUCIBLE BY FRACTIONAL CALCULUS

  • Gaboury, Sebastien;Rathie, Arjun K.
    • 대한수학회논문집
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    • 제29권3호
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    • pp.429-437
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    • 2014
  • Motivated by the recent investigations of several authors, in this paper we present a generalization of a result obtained recently by Choi et al. ([3]) involving hypergeometric identities. The result is obtained by suitably applying fractional calculus method to a generalization of the hypergeometric transformation formula due to Kummer.

Rhizopus nigricans에 의한 Progesterone 전환 반응의 경로 (Transformation Pathway of the Progesterone by Rhizopus nigricans)

  • 김명희;김말남
    • 미생물학회지
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    • 제29권2호
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    • pp.111-116
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    • 1991
  • Rhizopus nigricans produces 11.alpha.-hydroxyprogesternoe with a unidentified byproduct, which is hardly separated. Results of chromatography, IR and NMR spectroscopy identified the byproduct to be 11.alpha.-hydroxy-allopregnane-3,20-dione. R. nigricans was found to transform progesternoe into a monoform intermediate, 11.alpha.-hydroxyprogesterone, from which 11.alpha.-hydroxy-allopregnane-3,20-dione and 6.betha., 11.alpha. - dihydroxyprogesterone were formed respectively by 5.alpha.-reduction and 6.betha.-hydroxylation.

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Diterpene Glycoside from Acanthopanax koreanum

  • Kim, Young-Ho;Ryu, Jong-Hyeon;Chung, Bo-Sup
    • 생약학회지
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    • 제21권1호
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    • pp.49-51
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    • 1990
  • From tire root bark of Accnthopanax koreanum a new diterpene glycoside, mp $212{\sim}214^{\circ}$, was isolated. The structure was established as 15(R),16-dihydroxypimar-9(11)-ene-19-oic acid ${\beta}$-D-glucopyranosyl ester (sumogaside) oil the basis of spectroscopic methods and chemical transformation.

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GENERALIZATION OF EXTENDED APPELL'S AND LAURICELLA'S HYPERGEOMETRIC FUNCTIONS

  • Khan, N.U.;Ghayasuddin, M.
    • 호남수학학술지
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    • 제37권1호
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    • pp.113-126
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    • 2015
  • Recently, Liu and Wang generalized Appell's and Lauricella's hypergeometric functions. Motivated by the work of Liu and Wang, the main object of this paper is to present new generalizations of Appell's and Lauricella's hypergeometric functions. Some integral representations, transformation formulae, differential formulae and recurrence relations are obtained for these new generalized Appell's and Lauricella's functions.

분말야금법으로 제조된 FeSi2 열전특성 화합물의 열처리 시간에 따른 미세조직과 상변화 (Phase Transformation and Microstructure of FeSi2 Thermoelectric Compounds Manufactured by Powder Metallurgy)

  • 박경태;신진교;홍순직;천병선
    • 한국분말재료학회지
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    • 제17권6호
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    • pp.482-488
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    • 2010
  • In this study, $FeSi_2$ as high temperature performance capable thermoelectric materials was manufactured by powder metallurgy.The as-casted Fe-Si alloy was annealed for homogenization below $1200^{\circ}C$ for 3 h. Due to its high brittleness, the cast alloy transformed to fine powders by ball-milling, followed by subsequent compaction (hydraulic pressure; 2 GPa) and sintering ($1200^{\circ}C$, 12 h). In order to precipitate ${\beta}-FeSi_2$, heat treatment was performed at $850^{\circ}C$ with varying dwell time (7, 15 and 55 h). As a result of this experiment thermoelectric phase ${\beta}-FeSi_2$ was quickly transformed by powder metallurgical process. There was not much change in powder factor between 7h and 55h specimens.

Molecular Dynamics Study on the Structural Phase Transition of Crystalline Silver Iodide

  • Jun Sik Lee;Mee Kyung Song;Mu Shik Jhon
    • Bulletin of the Korean Chemical Society
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    • 제12권5호
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    • pp.490-494
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    • 1991
  • The ${\beta} to {\alpha}$ phase transition in silver iodide is studied with the (N, V, E) and (N, P, T) molecular dynamics (MD) method. In experiments, the phase transition temperature is 420 K. Upon heating of ${\beta}$ form, the iodine ions undergo hcp to bcc transformation and silver ions become mobile. MD simulations for the ${\beta}$ and ${\alpha}$ phases are carried out at several temperatures and the radial distribution functions (rdf) are obtained at those temperatures in the (N, V, E) ensemble. But the phase transition is not found in our calculation. Next the phase transition is studied with the (N, P, T) MD and we find some evidences of phase transition. At 3 Kbars and 2 Kbars the phase transition temperatu re is about 300 K. For 3.55 Kbars, the phase transition is higher (420 K) than the low pressure case. The phase transition temperature is somewhat dependent on the pressure in our calculations.

전분 분해성 산업용 Saccharomyces cerevisiae에서 Achlya bisexualis $\beta$-Amylase의 발현 특성 규명 (Characterization of Achlya bisexualis $\beta$-Amylase Expression in an Amylolytic Industrial Strain of Saccharomyces cerevisiae)

  • 이옥희;임미현;김지혜;유은혜;고현미;진종언;배석
    • 미생물학회지
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    • 제44권3호
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    • pp.264-269
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    • 2008
  • $\beta$-Amylase를 생산하여 전분 분해능을 갖는 산업용 효모를 개발하기 위해 산업용 Saccharomyces cerevisiae에서 Achlya bisexualis $\beta$-amylase (BAMY)유전자를 ADC1 promoter에 연결하여 구성적으로 발현시켰다. 효모의 형질전환은 $\delta$-서열을 재조합 부위로 하는integration 시스템을 이용하였다. Integration 시스템의 세균 유전자 부분은 제거되고 BAMY 유전자와 $\delta$-서열을 갖고 있는 짧은integrative cassette를 제조하였다. BAMY 유전자를 발현하는 재조합 S. cerevisiae 형질전환체는 세포외 배지로 45 kDa의 $\beta$-amylase를 분비하였고, $\beta$-amylase 활성은 A. bisexualis에 비해 약 18.5배 높았다. 형질전환체에 다중도입된 BAMY 유전자는 비선택배지에서 100세대 생장 후에도 안정되게 유지되었다. 각종전분을 기질로 했을 매 $\beta$-amylase의 활성은soluble starch를 기질로 했을 경우와 유사하게 높았고, 가수분해산물 분석 결과 maltose가 주 분해산물이었다.