• 생명과학회지
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• 제10권6호
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• pp.621-629
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• 2000

Camptothecin (CPT) is an antitumor alkaloid that has been isolated from the Chinese tree, Camptotheca acuminata. The cytotoxicity of CPT has been correlated to its inhibition of DNA topoisomerase (Topo) I by stabilizing drug-enzyme-DNA “cleavable complex" resulting in DNA single-strand breaks and DNA-protein crosslinks. This studies were designed to elucidate whether CPT regulates Topo I mediated by CPT in DNAs containing c-myc protooncogene. We have conducted experiments on Topo I purification, pUC-MYC I cloning and Topo I assay using electrophoresis, quantitative RT-PCR and Northern blotting techniques. CPT ingibited the relaxation activity of Topo I in pUC19 DNA at various concentrations (1-1000 $\mu$M), while it enhanced the cleavage of Topo I in the pUC-MYC I by forming a cleavable complex at relatively high concentrations (100-1000 $\mu$M). In HL-60 cells treated with CPT, the expression of c-myc gene was decreased over that in the control group with no changes in the expression of Topo I mRNA. Our results suggest that Topo I is the target of CPT cytotoxicity but it does not affect Topo I extression, and the suppression of c-myc mRNA expression by CPT is due to c-myc damage resulted from formation of a cleavable complex with CPT. CPT.

• 대한수의학회지
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• 제43권4호
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• pp.615-624
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• 2003

Vascular smooth muscle relaxation is modulated by an increase in cGMP subsequent to nitric oxide (NO) production by endothelial cells. The effects of cAMP and cGMP phosphodiesterase (PDE) inhibitors were investigated in phenylephrine-precontracted rat aorta rings by using the specific inhibitors of PDE I, III, IV and V as relaxing agents (calmodulin-activated PDE inhibitors, IBMX and $W_7$, type I; cAMP-specific PDE inhibitors, milrinone, type IV; Ro 20-1724, type III and cGMP-specific PDE inhibitor, zaprinast, type V). All the PDE inhibitors produced a concentration-dependent relaxation in the ring with intact endothelium (+E). Except for milrinone, all the PDE inhibitors-induced relaxations were inhibited by removal of extracellular $Ca^{2+}$, $N^G$-nitro-L-arginine, $N^G$-nitro-L-arginine methyl ester, methylene blue (MS) or nifedipine. The specific PDE I and PDE IV inhibitors both produced endothelium-independent relaxations which were inhibited by MS in -E rings. However, zaprinast had no effect in -E rings. Except for milrinone, sodium nitroprusside (a NO donor)-induced relaxation was significantly augmented by all PDE inhibitors in +E rings. The results suggest that I) the vasorelaxant properties of IBMX, $W_7$, Ro 20-1724 and zaprinast are dependent on endothelium or on interaction with $Ca^{2+}$ regulation, 2) each PDE is differently distributed in vascular tissues (endothelial and smooth muscle cells), 3) the vasodilations of PDE inhibitors are due to the increase of cAMP and cGMP formation through inhibition of cAMP- and cGMP-PDE and 4) the vasodilation action of milrinone does not involve in endothelial-cyclic nucleotide system.

• 대한화학회지
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• 제42권3호
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• pp.315-322
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• 1998

새로운 에메소겐 액정화합물들을 합성하였고, 이들의 열적 및 액정 성질을 DSC와 가열판이 부착된 편광현미경을 사용하여 조사하였다. 이 화합물들 즉, 1,10-bis[2,5-bis(4-substitutedphenoxycarbonyl)phenoxy]decane은 "H-자형" 이합체 대칭화합물의 구조로 중앙의 테페프탈로일 단위에 oxydecamethyleneoxy 격자를 통하여 상호 연결된 두 개의 bis(p-substitutedphenoxy)terephthalate 단위로 이루어졌다. 메소겐의 치환기는 X=-F, -H, -I, -Cl, -Br, $-NO_2,\;-CF_3,\;-OC_4H_9-CN$ 및 $-C_6H_5$를 바꾸어 보았다. $X=-OC_4H_9-CN$과 $C_6H_5$ 화합물은 단방성 네마틱액정이었으며 이에 비하여 X=-F, -H, -I, -Cl, -Br, $-NO_2$와 $-CH_3$는 액정이 아니었다. 이 화합물들의 네마틱 그룹 효율은 $-C_6H_5>-CN>-OC_4H_9$ 순이었다.

• 한국재료학회지
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• 제9권11호
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• pp.1148-1152
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• 1999

본 연구에서는 기존에 알려진 구리 전구체와 새롭게 개발된 전구체인 hfac (hexafluoroacetylacetonate) Cu(I) DMB (3,3-dimethyl-1-butene)를 비교 평가해보았다. (Hfac)Cu(I) (DMB)의 증가압은 $40^{\circ}C$에서 3 torr 정도로 기존에 잘 알려진 (hfac)Cu(I) vinyltrimethylsilane (VTMS) 보다 10배 정도 높은 것으로 나타났으며 그럼에도 불구하고 상당히 안정하여 $65^{\circ}C$에서 일주일 이상 가열하여도 변하지 않았다. 이 전구체로 100-$280^{\circ}C$에서 구리 박막을 증착할 수 있었으며 150-$250^{\circ}C$온도 범위에서 2.0$\mu\Omega$-cm의 순수한 구리 박막을 얻었다. 구리 박막의 증착 속도는 기존의 전구체보다 7~8배 정도 높은 것으로 나타났다.

• 동아시아식생활학회지
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• 제10권6호
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• pp.507-513
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• 2000

This study was conducted to investigate the shelf life of beef stored in antimicrobial pottery during 12days storage at 4'C and Five kinds of antimicrobial potteries were prepared with antimicrobial materials such as TiO$_2$, Ag (NO$_3$)$_2$, Cu(NO$_3$)$_2$ and Zn(NO$_3$)$_2$. In changes of color during storage, Hunter's L- and b-value of beef were not changed, but Hunter's a-value was low significantly. The pH of beef meats were low at 6 days, but were added from 6 days. TBA value of beef in "A" pottery containing TiO$_2$ 1% and "C" Pottery containing TiO$_2$ 0.5%, Cu(NO$_3$)$_2$ were lower than "B", "D" and "I" pottery. VBN contents of beef in "A", "B", "C", "D" and "I" Pottery stored during 12 days were 9.8, 12.5, 9.3, 11.9 and 13.7mg%, respectively. In changes of total plate count of beef during storage at 4$^{\circ}C$, the antimicrobial activity of "A" and "C" pottery were superior.g storage at 4$^{\circ}C$, the antimicrobial activity of "A" and "C" pottery were superior.ttery were superior.

• 생명과학회지
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• 제25권9호
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• pp.976-983
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• 2015

Achyranthoside C dimethyl ester (ACDE)는 우슬에서 분리한 oleanolic acid glycoside이다. 본 연구에서는 RAW264.7 대식세포에서 ACDE의 항염증 효과를 관찰하고 그 작용 기전을 연구하였다. ACDE는 세포에 독성을 유도하지 않으면서 heme oxygenase-1 (HO-1)의 발현을 유도하였다. ACDE 는 HO-1의 발현에 관여하는 전사인자인 nuclear factor E2-related factor 2 (Nrf2)를 핵으로 이동시켰다. 또한 ACDE에 의한 HO-1의 발현은 phosphatidylinositol 3-kinase (PI-3K) 및 mitogen activated protein kinases (MAPK) 억제제에 의해 감소되었으며, ACDE가 Akt, c-Jun kinase (JNK), extracellular signal regulated kinase (ERK), p38 kinase의 인산화를 유도하였다. 한편 ACDE는 lipopolysaccharide (LPS)로 인한 nitric oxide (NO)의 생성과 inducible NO synthase (iNOS) 발현을 억제하였으며 HO-1 siRNA를 처리했을 때 ACDE가 iNOS의 발현을 억제하지 못하였다. 이상의 결과를 종합해보면, ACDE는 대식세포에서 PI3K/Akt 및 MAPK와 Nrf2 신호전달과정을 통해 HO-1의 발현을 유도함으로써 NO와 같은 염증매개물질의 생성을 억제한다는 것을 알 수 있다. 이러한 연구결과는 ACDE가 항염증제로 사용될 수 있음을 시사한다.

• Korean Journal of Acupuncture
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• 제30권4호
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• pp.212-219
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• 2013

Objectives : Cirsium japonicum is a traditional Korean medicine that has been used in the treatment of inflammatory diseases such as appendicitis, hepatitis, pulmonary abscess and tumor. The aim of study was to elucidate anti-migratory activity of CJP(Cirsium japonicum pharmacopuncture) through regulation of inflammatory mediators in C6 glioma cell. Methods : Nitric oxide(NO) production was determined by using nitrite assay. The cell migration was analyzed by wound-healing assay and Boyden chamber assay. The expression levels of iNOS, and protein kinase C(PKC)-${\alpha}$ were measured by western blotting assay. Results : CJP showed a significant decrease on NO production. Moreover, glioma cell migration was effectively suppressed by CJP. Furthermore, CJP inhibited the expressions of iNOS and PKC-${\alpha}$ in C6 glioma cells. Conclusions : These results suggest that CJP inhibits glioma cell migration and iNOS expression through regulation of PKC-${\alpha}$. Therefore, it is expected that CJP could be an effective agents for blocking malignant progression of glioma.

• 대한수의학회지
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• 제33권2호
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• pp.345-350
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• 1993

Multiple ejaculates were collected from four male mongrel dogs. The second fraction and the small volume of third fraction from the ejaculates were divided and treated as follows : control; addition of the egg-yolk Tris extender to the semen at $37^{\circ}C$. group I; Removal of seminal plasma, group II; addition of the glycerolated extender at $4^{\circ}C$, group III Removal of seminal plasma and addition of glycerolated extender at $4^{\circ}C$. The semen cooled to $4^{\circ}C$ was equlibrated for 2hrs and preserved in refrigerator at $4^{\circ}C$. The preserved semen was evaluated for kinetics, morphology, motility and thermoresistance daily for 3 days. 1. The kinectics after preserved days 2 and 3 of group I was significantly higher than that of control(p<0.05). 2. There were no significant difference in abnormal morphology of each group between the periods of storage. 3. The motility after preserved day 1 and days 3 of group I was significantly higher than that of others(p<0.05), and the molity after preserved days 2 of group I and III was signficantly higher than that of others(p<0.05). 4. When the molity of preserved semen was measured during incubation at $37^{\circ}C$, the motility of four groups was declined at similar rates. There was no effect of removal of seminal plasma and glycerol addition on thermoresistance.

• 미생물학회지
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• 제40권2호
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• pp.178-182
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• 2004

Saccharomyces cerevisiae의 class I 키틴생합성 효소인 Chsl의 활성측정법을 적용하여 Aspergillus nidulans의 영양균사에서 class I 키틴생합성 효소인 ChsC의 활성측정을 시도하였다. 그 결과, A. nidulans의 class I 키틴생합성효소도 효모류의 경우와 마찬가지로 트립신 처리에 의하여 활성화되는 효소전구체형태(zymogenic form)로 존재함을 알 수 있었다. 그리고 A. nidulans 야생형의 class I 키틴 생합성 효소활성은 트립신 처리에 의하여 6배 가량 증가되었다. 반면, chsC 유전자가 파괴된 돌연변이주는 트립신 처리에 의하여 효소활성이 증가되지 아니하였을 뿐만 아니라, 효소활성의 수준도 트립신을 처리하지 아니한 야생형의 class I 키틴생합성 효소활성과 거의 동일한 수준이었다. 따라서, 트립신을 처리하여 측정한A. nidulans 야생형의 class I 키틴생합성 효소활성 값에서 트립신을 처리하지 아니한 야생형의 class I 키틴생합성 효소활성을 제외한 값이 A. nidulans 야생형의 ChsC 효소활성임을 알았다. 이러한 조건을 토대로 영양균사 생장과정 동안 ChsC의 효소활성을 측정한 결과, chsC 유전자의 발현양상과 유사하게 액체배양상태의 영양균사가 무성분화능을 획득하는 시기로 알려진 시간대에 효소의 활성이 증가하였다. 이러한 결과는 이미 보고된 바와 같이 chs 유전자가 A. nidulans의 영양균사 생장에 관여함을 시사하고 있다.

• 한국동물학회지
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• 제25권2호
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• pp.81-92
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• 1982

한국내 4개 지역에서 채집된 17마리의 등줄쥐 (Apodemus agrarius coreae)의 G-와 C-banding patter을 분석한 결과 첫 번째 염색체쌍의 다형현상 (차단부 및 단부)은 동원체 주위의 이질염색질이 어떤 때는 short arm의 형태로 나타나기 때문이라는 것이 밝혀졌다. 한국내 2개 지역에서 채집된 곰쥐 (R. rattus rufescens)의 G-와 C-banding pattern을 분석한 결과 첫 번째 염색체쌍의 다형현상 (차단부 및 단부)은 pericentric inversion에 기인한다는 것이 밝혀졌다.