• Journal of Acupuncture Research
• /
• v.19 no.5
• /
• pp.10-27
• /
• 2002

연구목적 : 면역억제와 활성 작용을 지닌 것으로 알려진 녹용약침(CPH)을 type II collagen 유발 관절염 (CIA) 백서와 인산이온 유발 연골세포의 세포사에 있어 보호활성 효과를 연구하였다. 연구방법 : 7주된 암컷 Sprague-Dawley 쥐를 collagen으로 관절염을 유발시킨 후 CPH의 효과를 관절염 점수, 체중감소 등의 평가기준으로 검정하였다. CPH는 일주일에 5번씩 각각 10, 20, 30 및 $100{\mu}g/kg/day$의 용량으로 양측 신수혈에 주입하였다. 연구결과 : 1. 300 mg/kg/day CPH처리로 관절염점수의 감소를 기초로 한 collagen 유발 관절염의 발생을 완전히 억제하였으며 관절염 점수상에서 CPH의 효과작인 용량은 64 mg/kg이었다. 2. CHP는 쥐의 간에 있는 DHO-DHase 활성을 $Ki=843{\pm}43{\mu}g/ml$의 비교적 높은 비활성으로 억제하였다. 3. 관절염관련 세포의 증식억제활성을 검정한 결과 CPH의 항 증식효과는 세포주기 S기에서 정지시키는 활성을 나타내었다. 4. 쥐의 늑연골로부터 완전히 최종 분화된 비대연골세포를 분리 배양하여 3~5mM/L Pi를 첨가함으로서 세포사멸을 측정하였다. $10{\mu}g/ml$ CPH 처리에 의한 보호(억제) 효과가 Pi-유발 연골세포의 세포사에 대한 Na-Pi cotransport의 경쟁적 저해제로 알려진 phosphonoformic acid(PFA)의 억제활성과 상응하는 수준으로 CPH의 활성을 확인하게 되었다.

• Journal of Electrochemical Science and Technology
• /
• v.2 no.4
• /
• pp.187-192
• /
• 2011

Photoelectrochemical performances of ZnO electrodes are enhanced by coupling with cobalt-based catalyst (CoPi) in phosphate electrolyte (pH 7). For this study, hexagonal pillar-shaped ZnO nanorods are grown on ZnO electrodes through a chemical bath deposition, onto which CoPi is deposited with different photodeposition times (10-30 min). A scanning electron microscopic study indicates that CoPi deposition does not induce any change of ZnO morphology and an energy-dispersive X-ray spectroscopic analysis shows that inorganic phosphate ions (Pi) exist on ZnO surface. Bare ZnO electrodes generate the current of ca. $0.36mA/cm^2$ at a bias potential of 0.5 V vs. SCE, whereas ZnO/CoPi (deposited for 10 min) has ca. 50%-enhanced current ($0.54mW/cm^2$) under irradiation of AM 1.5G-light ($400mW/cm^2$). The excess loading of CoPi on ZnO results in decrease of photocurrents as compared to bare ZnO likely due to limited electrolyte access to ZnO and/or CoPi-mediated recombination of photogenerated charge carriers. The primary role of CoPi is speculated to trap the photogenerated holes and thereby oxidize water into molecular oxygen via an intervalency cycle among Co(II), Co(III), and Co(IV).

• Membrane Journal
• /
• v.5 no.2
• /
• pp.89-96
• /
• 1995

The monolayer characteristics of phosphate amphiphiles with azobenzene at air/water interface were studied by the measurment of $\pi-A$ curves and absorption spectra. Immediately after being spread on the water surface, these amphiphiles having strong intermolecular hydrogen bonding interactions showed the typical absorption spectra which resulted from domain formation. But the aggregated domains could be controlled by changing the subphase conditions (adding bulky salt and rasing pH). Addition of metal ions in subphase changes the molecular orientation of monolayer. As the metal ion charge increases ($1\leq2$ < 3 < 4 valence), the absorption maximum (310nm) of the amphiphile with azobenzene shifts to a longer wavelength (350nm) which means that the orientation of the amphiphile is tilted. These results suggest that the molecular orientation, and furthermore the aggregation state of monolayer can be possibly controlled by the interaction of metal ions with different charge types.

• Applied Biological Chemistry
• /
• v.43 no.3
• /
• pp.163-168
• /
• 2000

To remove phosphate accumulated in the soil and water, Acinetobacter lwoffi PO8 possessing a high ability to accumulate phosphate was isolated from a active sludge. Bacterium was cultured in the liquid medium containing $150\;{\mu}g/mL$ of phosphate at $30^{\circ}C$ in different culture conditions to examine intracellular phosphate uptake. The initial pH in the range of $7.5{\sim}8.5$ was effective on the growth and phosphate uptake of the strain. Glycerol and arabinose used as a carbon sources showed 93 and 91% the phsphate uptake, respectively. Among the nitrogen sources, ammonium salt such as $NH_4NO_3$ and $(NH_4)_2SO_4$ was effectively utilized on the phosphate uptake compared with amino compounds. The rate of phosphate uptake of $NH_4NO_3$, and $(NH_4)_2SO_4$, was 95 and 96%, respectively The growth and Phosphate uptake ability in the strain were significantly promoted when metal ions were added in the medium; $Co^{2+}$, however, was not utilized by the strain. The capacity of phosphate uptake was enhanced to $10{\sim}20%$ when arginine, methionine, or lysine was added. Using $^{32}P$ to examine the uptake Pattern of intracellular phosphate, experiment result showed that polyphosphate was largely found in the fraction of intracellular inorganic phosphate of Acinetobacter lwoffi PO8.