• 대한화학회지
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• 제29권5호
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• pp.490-495
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• 1985

팔라듐(II)의 새로운 착물인 $[Pd((ieaa)_2-en)]$ 및 [PdCl((ieaa)-l-pn)]을 합성하였다. 여기서 $(ieaa)_2-en$과 (ieaa)-l-pn은 각각 N,N'-ethylenebis(isonitrosoethylacetoacetate imine) 및 l-N-(2-aminopropyl)-isonitrosoethylacetoacetate imine을 표시한다. 합성된 이들 팔라듐(II) 착물들은 전자흡수(AB) 스펙트럼, 원이색성(CD) 스펙트럼, C-13핵자기공명스펙트럼, 적외선 및 라만스펙트럼등의 측정결과를 기초로 그 특성을 연구하였다. 염화팔라듐(II)과 ethylenediamine을 첨가한 isonitrosoethylacetoacetate (ieaa)와의 반응에서 생성된 팔라듐착물에서는 $(ieaa)_2-en$형의 Schiff 염기, 한편 ethylenediamine 대신 l-propylenediamine을 사용한 비슷한 반응으로 생성된 착물에서는 (ieaa)-l-pn형의 Schiff염기로 나타낸다. 이러한 구조형성의 차이를 사용된 diamine의 입체화학적 관점에서 검토한다.

• 환경생물
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• 제22권1호
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• pp.89-92
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• 2004

The effects of different light quality on the change of membrane potential difference (PD) of the guard cell in the intact leaf have been investigated. The mombrane PD was about -5.5 mV by white light of 600 $\mu$moles $m^{-2}\; s^{-1}$. The mean PD of change caused by red light was about -5.2 mV at the light intensity of 80 $\mu$moles $m^{-2}\; s^{-1}$. Membrane PD of guard cells in response to blue light was saturated at low light intensity. However, red and green light enhanced the change of membrane PD of guard cells with increasing intensity. In green light the biggest change of memrane PD was around -4 mV, whereas, with blue light the change of of memrane PD was around -2 mV. Accordingly, the membrane PD of guard cell showed the different degree of hyper-polarization by each wavelength.

• Bulletin of the Korean Chemical Society
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• 제9권4호
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• pp.198-202
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• 1988

Several new palladium(II) complexes of aminophosphines, $(Pd(L)X_2)$, (L = $Ph_2PNH$ ++ $NR_2$; R = $CH_3(L_1)$, $C_2H_5(L_2)$ : X = Cl, Br, I, and NCS) that contain two different donor atoms of nitrogen and phosphorus as ${\pi}$-electron acceptor, were synthesized and characterized by conductivity measurement, ir, and UV/Vis-spectra. For the dithiocyanatopalladium(II) complexes with aminophosphines, it was confirmed that the thiocyanate group trans to phosphorus is coordinated as Pd-NCS mode and the one trans to nitrogen as Pd-SCN mode, and the aminophosphines form six-membered chelate ring. The spectra of dihalogenopalladium(II) complexes with aminophosphines show that the band maxima are shifted to the short wavelengths as the concentration is decreased.

• 대한의생명과학회지
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• 제30권2호
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• pp.37-48
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• 2024

Liposomes are one of the most actively studied and promising drug delivery systems for the treatment of various diseases. In this study, an aptamer-conjugated liposome called "aptamosome" was used, in which an anti-PD-L1 aptamer targeting cancer cells was conjugated to the liposome. These aptamosomes showed remarkable cellular uptake and efficient delivery to Lewis lung carcinoma 2 (LL/2) cancer cells. In addition, suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor (HDACi), was delivered through this aptamer to induce a strong anticancer immunotherapeutic effect. The results of this study showed that when LL/2 cells were treated with SAHA-entrapped aptamosome [SAHA] and liposome [SAHA] and free SAHA, aptamosome [SAHA] improved cell death compared with that of liposomes [SAHA] or free SAHA, and it has demonstrated anticancer efficacy. Moreover, aptamosome [SAHA] induce the secretion of chemokines that promote the migration of activated T cells into tumor tissues. Finally, in vivo experiments showed that aptamosome [SAHA] significantly inhibited the growth rate of LL/2 tumors. Therefore, liposomes combined with an anti-PD-L1 aptamer for efficient SAHA delivery are suggested as an excellent model for drug delivery systems suitable for targeting cancer cells.

• Bulletin of the Korean Chemical Society
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• 제18권11호
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• pp.1162-1166
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• 1997

Nature of palladium(Ⅱ) complexes with 7-membered chelates was studied by experimental and theoretical methods on a Pd(L)Cl2 system, where L is Ph2PNHCH2CH2NHPPh2(L1), Ph2PNHC6H4NHPPh2(L2). The palladium(Ⅱ) complexes were prepared and characterized by elemental analysis, IR, UV, 1H, and 31P NMR spectroscopy. Ab initio calculations with geometry optimizations were also performed for related model systems, Pd(L)Cl2; L=R2PNH(CH2)2NHPR2(L3), R2PNHC6H4NHPR2(L4), R2P(CH2)4PR2(L5), R2PCH2(C6H4)CH2PR2(L6); R=H, CH3.

• 대한화학회지
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• 제42권4호
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• pp.369-377
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• 1998

이소옥사졸과 그의 유도체가 배위된 팔라듐(II) 및 백금(II)착물$([M(L)_2X_2]$, M=Pd(II), Pt(II); L=isoxazole(isox), 3,5-dimethylisoxazole(3,5-diMeisox), 3-methyl, 5-phenylisoxazole(3-Me, 5-Phisox), and 4-am-ino 3,5-dimethylisoxazole(4-ADI); X=Cl, Br)의 항암활성을 분자역학(MM2)법으로 최소에너지를 갖는 구조를 구한 후 확장분자궤도함수(EHMO)법으로 조사하였다. 중심금속의 $d_x^{2-}_y^2$ 궤도함수와 할로겐 원자의 $p_x$ 궤도함수 사이의 ${\sigma}MO$ 에너지준위$(E_{{\sigma}(Pd,Pt-X)})$가 질소원자의 $p_x$ 궤도함수 사이의 ${\sigma}MO$ 에너지준위 $(E_{\sigma}(Pd,Pt-N))$보다 예외없이 더 높아서 결합이 약함을 알 수 있었다. 아울러 같은 착물에서 cis- 보다 trans-착물에서 $(E_{\sigma}(Pd,Pt-X))$ 값이 더 높아서 결합이 약함을 알았다. 또한 평면형 리간드가 배위될 경우 cis-, trans- 이성체 모두 백금착물에서보다 팔라듐착물에서 $X^-$ 이온의 이탈이 더 용이했다. 다라서 $X^-$ 이온으로 떨어져 나가는 용이성이 항암활성과 어떤 관계가 있을 것으로 생각하고 $E_{{\sigma}(Pd,Pt-N)}-E_{{\sigma}(Pd,Pt-X)}({\Delta}E_{{\sigma}(N-X)})$과 저해활성 계수인 logIA의 값를 도시하였던바 실험치와 상관 계수가 0.96인 좋은 직선성이 성립함을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제28권1호
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• pp.77-80
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• 2007

As neurofilament proteins are major cytoskeletal components of neuron, abnormality of neurofilament is proposed in brain with neurodegenerative disorders such as Parkinson's disease (PD). Since oxidative stress might play a critical role in altering normal brain proteins, we investigated the oxidative modification of neurofilament-L (NF-L) induced by the reaction of cytochrome c with H2O2. When NF-L was incubated with cytochrome c and H2O2, the protein aggregation was increased in cytochrome c and H2O2 concentrationsdependent manner. Radical scavengers, azide, formate and N-acetyl cysteine, prevented the aggregation of NFL induced by the cytochrome c/H2O2 system. The formations of carbonyl group and dityrosine were obtained in cytochrome c/H2O2-mediated NF-L aggregates. Iron specific chelator, desferoxamine, prevented the cytochrome c/H2O2 system-mediated NF-L aggregation. These results suggest that the cytochrome c/H2O2 system may be related to abnormal aggregation of NF-L which may be involved in the pathogenesis of PD and related disorders.

• Korean Chemical Engineering Research
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• 제47권6호
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• pp.768-774
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• 2009

본 연구는 통성 혐기성 미생물인 K. pneumoniae DSM4799을 이용하여 순수 글리세롤과 국내 바이오디젤 생산공정에서 발생된 폐글리세롤로부터 1,3-PD을 생산하기 위한 연구로서, 혐기 및 호기 조건, 배양온도, 글리세롤 농도, pH에 따른 1,3-PD 생산성 비교를 통해 최적 배양조건을 찾고자 하였다. K. pneumoniae DSM4799를 혐기조건과 호기/혐기 2단계 배양을 한 결과, 혐기조건에서 더 효율적인 1,3-PD 생산이 이루어졌다. 배양 온도를 $26{\sim}37^{\circ}C$로 변화시키면서 배양한 결과, $30{\sim}33^{\circ}C$에서 높은 1,3-PD 생산성을 나타내었고, 글리세롤 농도는 글리세롤의 종류에 상관없이 60 g/L 이상에서 균주의 성장 및 1,3-PD 생산이 저해되는 현상을 관찰할 수 있었다. 폐글리세롤 사용시 순수 글리세롤에 비해 초기 1,3-PD 생산은 감소하였으나, 48시간 후에는 오히려 더 높은 농도의 1,3-PD를 생산하였다. 유가식 배양으로 글리세롤 농도를 40 g/L 이하로 조절하면서 pH 조절유무에 따른 1,3-PD 및 부산물의 변화를 살펴본 결과, pH를 7.0으로 유지시켰을 때 pH 조절을 하지 않은 경우보다 25% 향상된 1,3-PD 수율을 나타내었다(0.56 g/g vs. 0.45 g/g). 본 연구를 통해 K. pneumoniae DSM4799를 이용하여 1,3-PD 생산시 혐기조건, 온도 $30^{\circ}C$, 순수 또는 폐글리세롤 40 g/L 이하, pH 조절 등의 배양조건이 적합함을 알 수 있었으며, 최적화된 배양조건을 통해 보다 가격경쟁력이 있는 생물학적 1,3-PD 생산이 가능할 것으로 기대된다.

• 한국결정학회지
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• 제1권2호
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• pp.66-75
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• 1990

Pd-Te계의 상평형도를 시차열분석, X선회절분석, 전자현미분석, 반사현미경을 사용해 연구하였다. 본 계의 0-50 at.%Te 부분의 새로운 상관계가 정립되었다. 본 계에는 Pd17Te4, Pd20Te7, Pd8Te3, Pd7Te3, PdgTe4, Pd3Te2, PdTe, PdTe2 등 8개의 화합물이 존재하며 이중 Pd17Te4와 Pd7Te3는 처음 보고되는 신종 화합물이다. Pd17Te4는 등축정계이며 공간군 Fd3r에 속하며 단위포 크기 (a)는 12. 678(5)차이다. PdaTe.4와Pd7Te3의 X선회절분말자료는 사방정계의 단위포 a=12.843(3), b=15.126(3), c=11.304(2)A와 단사 정계의 단위포 a=7.444(1), b=13.918(2), c=8.873 (2)il, β=92.46(2)에 의해 각각 격자지수화가 가능하였다. 본계에 존재하는 합성 화합물의 일부 물리적, 광학적 자료를 새로 보고하였다.

• BMB Reports
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• 제44권1호
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• pp.64-69
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• 2011

A peroxidase (PD-cP; 0.47 mg/100 g leaves) was purified from autumn leaves of Phytolacca dioica L. and characterized. PD-cP was obtained by acid precipitation followed by gel-filtration and cation exchange chromatography. Amino acid composition and N-terminal sequence of PD-cP up to residue 15 were similar to that of Spinacia oleracea (N-terminal pairwise comparison showing four amino acid differences). PD-cP showed a molecular mass of approx. 36 kDa by SDS-PAGE, pH and temperature optima at 3.0 and $50.0^{\circ}C$, respectively and seasonal variation. The Michaelis-Menten constant ($K_M$) for $H_2O_2$ was 5.27 mM, and the velocity maximum ($V_{max}$) $1.31\;nmol\;min^{-1}$, while the enzyme turnover was $0.148\;s^{-1}$. Finally, the presence of $Ca^{2+}$ and $Mg^{2+}$ enhanced the PD-cP activity, with $Mg^{2+}$ 1.4-fold more effective than $Ca^{2+}$.