• Journal of Life Science
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• 제11권1호
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• pp.57-64
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• 2001

The cDNA encoding human NeuAc ${\alpha}$2,3Gal$\beta$ 1,3GalNAc GalNac ${\alpha}$2,6-Sialyltransferase (hST6GalNac IV) was isolated by screening of human fetal liver cDNA library with a DNA probe generated from the cDNA sequence of mouse ST6Gal NAc IV (mkST6GalNAc IV). The cDNA sequence included an open reading frame coding for 302 amino acids, and comparative analysis of this cDNA with mST6GalNAc IV showed that each sequence of the predicted coding region contains 88% and 85% identifies in nucleotide and amino acid levels, respecively. The primary structure of this enzyme suggested a putative domain structure, like that in other glycosyltransferases, consisting of a short N-terminal cytoplamic domain, a transmembrane domain and a large C-terminal active domain. This enzyme expressed in COS-7 cells echibited transferase activity toward NeuAc ${\alpha}$2,3Gal$\beta$ 1,3GalNAc, fetuin and GM1b, although the activity toward the later is very low, no significant activity being detected toward Gal${\beta}$ 1,3Gal NAc or asialofetuin, the other glycoprotein substrates tested. The $^{14}$ C-sialylated residue of fetuin sialylated by this enzyem with CMP-[$^{14}$C]NeuAc was sensitive to treatment with ${\alpha}$2,8-specific sialidase of Vibrio cholerae but resistant to treatment with ${\alpha}$2,3-specific sialidase (NaNase I), and ${\alpha}$2,3- and ${\alpha}$2,8-specific sialidase of Newcastle disease virus. These results clearly indicated that the expressed enzyme is a type of GalNAc ${\alpha}$2,6-sialyltransferase like mST6GalNAc IV, which requires sialic acid residues linked to Gal${\beta}$1,3GalNAc-residues for its activity.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권4호
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• pp.331-338
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• 2004

Stress transfer to the surrounding tissues is one of the factors involved in the design of dental implants. Unfortunately, insufficient data are available for stress transfer within the regenerated bone surrounding dental implants. The purpose of this study was to investigate the concentration of stresses within the regenerated bone surrounding the implant using three-dimensional finite element stress analysis method. Stress magnitude and contours within the regenerated bone were calculated. The $3.75{\times}10-mm$ implant (3i, USA) was used for this study and was assumed to be 100% osseointegrated, and was placed in mandibular bone and restored with a cast gold crown. Using ANSYS software revision 6.0, a program was written to generate a model simulating a cylindrical block section of the mandible 20 mm in height and 10 mm in diameter. The present study used a fine grid model incorporating elements between 165,148 and 253,604 and nodal points between 31,616 and 48,877. This study was simulated loads of 200N at the central fossa (A), at the outside point of the central fossa with resin filling into screw hole (B), and at the buccal cusp (C), in a vertical and $30^{\circ}$ lateral loading, respectively. The results were as follows; 1. In case the regenerated bone (bone quality type IV) was surrounded by bone quality type I and II, stresses were increased from loading point A to C in vertical loading. And stresses according to the depth of regenerated bone were distributed along the implant evenly in loading point A, concentrated on the top of the cylindrical collar loading point B and C in vertical loading. And, In case the regenerated bone (bone quality type IV) was surrounded by bone quality type III, stresses were increase from loading point A to C in vertical loading. And stresses according to the depth of regenerated bone were distributed along the implant evenly in loading point A, B and C in vertical loading. 2. In case the regenerated bone (bone quality type IV) was surrounded by bone quality type I and II, stresses were decreased from loading point A to C in lateral loading. Stresses according to the depth of regenerated bone were concentrated on the top of the cylindrical collar in loading point A and B, distributed along the implant evenly in loading point C in lateral loading. And, In case the regenerated bone (bone quality type IV) was surrounded by bone quality type III, stresses were decreased from loading point A to C in lateral loading. And stresses according to the depth of regenerated bone were distributed along the implant evenly in loading point A, B and C in lateral loading. In summary, these data indicate that both bone quality surrounding the regenerated bone adjacent to implant fixture and load direction applied on the prosthesis could influence concentration of stress within the regenerated bone surrounding the cylindrical type implant fixture.

• Asian Pacific Journal of Cancer Prevention
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• 제15권15호
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• pp.6227-6232
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• 2014

Background: Oral squamous cell carcinoma (OSCC) remains as one of the most difficult malignancies to control because of its high propensity for local invasion and cervical lymph node dissemination. The aim of present study was to evaluate the efficacy of novel pH and temperature sensitive doxorubicin-methotrexate-loaded nanoparticles (DOX-MTX NP) in terms of their potential to change the VEGF-C expression profile in a rat OSCC model. Materials and Methods: 120 male rats were divided into 8 groups of 15 animals administrated with 4-nitroquinoline-1-oxide to induce OSCCs. Newly formulated doxorubicin-methotrexate-loaded nanoparticles (DOX-MTX NP) and free doxorubicin were IV and orally administered. Results: Results indicated that both oral and IV forms of DOX-MTX-nanoparticle complexes caused significant decrease in the mRNA level of VEGF-C compared to untreated cancerous rats (p<0.05). Surprisingly, the VEGF-C mRNA was not affected by free DOX in both IV and oral modalities (p>0.05). Furthermore, in DOX-MTX NP treated group, less tumors characterized with advanced stage and VEGF-C mRNA level paralleled with improved clinical outcome (p<0.05). In addition, compared to untreated healthy rats, the VEGF-C expression was not affected in healthy groups that were treated with IV and oral dosages of nanodrug (p>0.05). Conclusions: VEGF-C is one of the main prognosticators for lymph node metastasis in OSCC. Down-regulation of this lymph-angiogenesis promoting factor is a new feature acquired in group treated with dual action DOX-MTX-NPs. Beside the synergic apoptotic properties of concomitant use of DOX and MTX on OSCC, DOX-MTX NPs possessed anti-angiogenesis properties which was related to the improved clinical outcome in treated rats. Taking together, we conclude that our multifunctional doxorubicin-methotrexate complex exerts specific potent apoptotic and anti-angiogenesis properties that could ameliorate the clinical outcome presumably via down-regulating dissemination factor-VEGF-C expression in a rat OSCC model.

• Journal of Plant Biology
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• 제11권1호
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• pp.33-37
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• 1968

Present investigation was carried out in order to make clear the fertility, morphological characters, and chromosome numbers of interspecific hybrids of Chrysanthemum Zauadskii, C. indicum, and C. lavandulaefolium. 1. Hybrids were not self-pollinated. When sib-crossed the fertility was 1.3~19.3%. 2. F2 individuals were variable in their morphological Characters. 3. Chromosome numbers of three putative parents were different from those reported previously: C. zawadskii 2n=36, C. indicum 2n=20, C. lavandulaefolium 2n=16, $C. indicum{\times}C. zawadskii 2n=28, C. zawadskii{\times}C. indicum-1 2n=28, C. zawadskii{\times}C. indicum-2 2n=28, C. zawadskii{\times}C. indicum-3 2n=28, C. zawadskii{\times}C. indicum-4 2n=28, C. zawadskii{\times}C. indicum-5 2n=28, C. zawadskii {\times}C. lavandulaefolium-1 2n=26, C. zawadskii{\times}C. lavandulaefolium-2 2n=26.$

• Asian-Australasian Journal of Animal Sciences
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• 제21권3호
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• pp.353-357
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• 2008

A series of studies has been conducted to establish a base infrastructure for an ovarian follicle culture system in the porcine and this study was designed to develop an effective retrieval protocol of preantral follicles. Five different methods using collagenase type I (A) or IV (B, C1, C2 and C3), which employed different treatment durations and/or conditions, were employed and sliced ovarian tissue of prepubertal gilts was provided for the retrieval. A significant increase in total number of follicles retrieved was detected when collagenase IV (methods B or C) was used. In total, more ovarian follicles were retrieved by method B undertaking agitation and method C2 without the agitation than method C1 and C3, while the number of preantral follicles collected was the largest in method B. Neither incubation in 5% $CO_2$ in air atmosphere instead of the agitation nor increased duration of enzymatic treatment up to 120 minutes improved the efficiency of follicle retrieval. There were no differences in the number of follicles retrieved from intact ovaries and from used ovaries for oocyte collection. These results demonstrate the collagenase IV treatment with agitation is effective for retrieving porcine preantral follicles from the ovaries.

• 대한화학회지
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• 제18권4호
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• pp.267-271
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• 1974

네자리 schiff base 리간드로서 N,N-비스(살리실알데히드)에틸렌디이민과 Mo(IV), Mo(V), Mo(VI) 및 Mo(III)의 각 산화상태인 몰리브덴이온들과의 반응으로서 새로운 착물$[MoO_2(C_{16}H_{14}O_2-N_2)], [MoO(C_{16}H_{14}O_2N_2)]_2O, (Mo(SCN)(C_{16}H_{14}O_2N_2)]_2O$들을 합성하였다. 이들 착물들은 리간드와 몰리브덴의 몰비가 1:1이며, 6배위의 가상적인 구조로 주어짐을 원소 분석치와 가시부 및 적외선 흡수스펙트럼, T.G.A., D.T.A. 및 X-ray 회절의 고찰로서 알아보았다.

• 한국유기농업학회지
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• 제18권1호
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• pp.63-74
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• 2010

본 연구는 유기액비 관비가 '녹광(세미니스)' 고추의 생육과 수량에 미치는 영향을 구명코자 실시하였다. 유기액비 조성에 따라 대조구(화학비료시비), 유기액비 I(계분 : 어분 : 대두박, 2:1:1), 유기액비 II(계분 : 골분 : 대두박, 2:1:1), 유기액비 III(계분 : 골분, 1:1), 유기액비 IV(계분 : 쌀겨 : 대두박, 2:1:1) 등 5처리를 두었다. 유기액비 조성재료와 비율에 따른 액비의 pH와 EC는 각각 6.5~6.8와, $2.91{\sim}3.69dS{\cdot}m^{-1}$의 분포를 나타냈다. 유기액비 조성 비율에 따른 C/N율은 유기액비 IV가 5.75로 가장 높았으며, 그 외 처리는 처리간에 차이가 없었다. 주당 총과중은 유기액비 IV 처리구에서 1,558g으로 가장 무거웠으며 총과수는 대조구에 비해 23.7% 증가하였다. 홍고추의 캡사이신 함량은 유기액비 I과 II에서 대조구에 비하여 증가하였으며, 유기액비 III과 IV 관비구에서는 감소하였다. 당도는 유기액비 IV 관비구에서 $10.0^{\circ}Brix$로 가장 높았다.

• 미생물학회지
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• 제14권3호
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• pp.117-127
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• 1976

A cellulase fraction (F IV-1) purified to about 8-folds was obtained from crude cellulase prepared from the wheat bran culture of S.atra. The partial purification of the enzyme was made by DEAE Sephadex and Sephdex cloumn chromatography in conjuction with ammonium sulfate precipitation. After stading at various pH's for 22 hours at $20^{\circ}C$, F IV-1 was most stable at pH 5.0 but when the enzyme fraction was stood for 74 hours, the point of pH stability was raised to around pH 6.0-7.0. After heating at various temperatures for 1 hour, F IV-1 was most stable at $20^{\circ}C$. The optimal enzyme activities of F IV-1 were seen at pH 6.0 and $50^{\circ}C$. The optimal concentrations of $Zn^{++}\;and\;Ca^{++}$ for the activities of crude cellulase were 6 and 4 mM respectively, but $Ca^{++}$ inhibited the enzyme activity at concentrations below 2 mM and above 6mM. Both $Cu^{++}\;and\;Mn^{++}$ ions inhibited cellulase activities and a ocmplete inactivation of crude cellulase was achieved at concentratioins of 5 and 2 mM of ions respectively. When Na-CMC was used as substrate, the Km values of crude cellulase and F IV-1 were calculated to be $5{\times}10^{-4}\;and\;2{\times}10^{-5}mM$, and V values 32 and 1.35 mmoles/hour, respectively. The Ki values of $Mn^{++}$ for crude cellulase and F IV-1 were found to be $8{\times}10^{-2}\;and\;3{\times}10^{-2}\;mM\;while\;those\;of\;Cu^{++}\;were\;at\;2{\times}10^{-1}\;and\;1{\times}10^{-1}\;mM\;respectively.\;Both\;Mn^{++}\;and\;Cu^{++}$ showed competitive inhibition with substrate.

• Journal of the Korean Wood Science and Technology
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• 제9권2호
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• pp.1-30
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• 1981

알칼리 펄프화중(化中)에 생성(生成)되는 리그닌의 착색구조(着色構造)를 구명(究明)하기 위(爲)하여 바닐린알코올[${\alpha}-^{13}C$] 과이아실 글리세롤-${\beta}$-아릴에테르[${\alpha}-^{13}C$] 혹은 [${\gamma}-^{13}C$] 페닐쿠마란[${\alpha}-^{13}C$] 구조(構造)를 각각(各各) 165$^{\circ}C$에서 1.5~3시간(時間) 알칼리용액을 처리한 후(後) 반응생성물(反應生成物)을 단리(單離) 또는 반응혼합물(反應混合物)을 $^{13}C$-NMR로 조사(調査)한 결과(結果), 바닐린아코올의 알칼리 처리(處理)는 Ca-$C_1$ 및 Ca-$C_5$의 결합(結合)을 갖는 축합체(縮合體)(II-1~5)로 되며, 이들은 공기산화(空氣酸化)에 의(依)해 퀴노이드 공역형구조(共役型構造)(Fig 3-7)로 산화(酸化)되며, 과이아실글리세롤 -${\beta}$- 아릴에테르의 알칼리 처리(處理)는 ${\alpha}$-아릴-${\beta}$-아록시퀴논구조(構造)(IV-15, IV-16) 디과이아실-1, 4-펜탄디엔 ${\beta}$, ${\beta}$' -디아록시스티렌메탄(V-4) ${\beta}$-아록시스티렌메탄(V-6)이 생성(生成)되며 스티렌메탄 구조(構造)는 공기산화(空氣酸化)에 의(依)해 O-퀴논메티드구조(V-8, V-9)로 된다. 페닐쿠마란은 알칼리처리(處理)에 의(依)해 다량(多量)의 스틸벤유도체(誘導體)를 생성(生成)하지만 이스틸벤구조가 퀴논구조로 산화되기 보다는 2량체(量體)(IV-11)로 안정화(安定化)되는 경향(傾向)이 있다. 이상(以上)과 같은 착색구조(着色構造)는 반응기구의 견지에서 알칼리 펄프화중(化中)에 생산되는 중요한 착색구조(着色構造)라고 생각된다.

• 대한화학회지
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• 제56권1호
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• pp.28-33
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• 2012

The kinetics of ruthenium(III) chloride catalyzed oxidation of butanone and uncatalyzed oxidation of cyclohexanone by cerium(IV) in sulphuric acid medium have been studied. The kinetic rate law(I) in case of butanone conforms to the proposed mechanism. $$-\frac{1}{2}\frac{d[Ce^{IV}]}{dt}=\frac{kK[Ru^{III}][butanone]}{1+K[butanone]}$$ (1). However, oxidation of cyclohexanone in absence of catalyst accounts for the rate eqn. (2). $$-\frac{1}{2}\frac{[Ce^{IV}]}{dt}=\frac{(k_1+k_1K^'[H^+])[Ce^{IV}][Cyclohexanone]}{1+K_3[HSO_4^-]}$$ (2) Kinetics and activation parameters have been evaluated conventionally. Kinetically preferred mode of reaction is via ketonic and not the enolic forms.