• 약학회지
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• 제41권2호
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• pp.225-232
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• 1997

The in vitro antibacterial activity of DWP20367 (1-Cyclopropyl-6-fluoro-8-chloro-7-(2,7-diazabicyclo[3,3,0]oct-4-ene-7-yl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid), a new broad-spectrum fluoroquinolone, was compared with those of ciprofloxacin (CPFX), sparfloxacin (SPFX) and ofloxacin (OFLX). DWP20367 was showed antibacterial activity much higher than CPFX, SPFX and OFLK against gram-positive bacteria, while it was slightly more superior to quinolones against gram-negative bacteria. DWP20367 was particularly effective against MRSA, and its $MlC_{90}$ against clinical isolates of methicillin-susceptible S. aureus, low methicillin-resistant S. aureus and high methicillin-resistant S. aureus were 0.098, 0.781 and 1.563 micro g/ml, respectively. Against S. pneumoniae, MIC90 of DWP20367 was 2- to 8-fold higher than those of CPFX. With a view of MIC90, DWP20367 showed slightly more potent activity against P. aeruginosa and E. coli isolates than the control quinolones. DWP20367 activity was not affected by inoculum size and medium pH. But addition of $Mg^{2+}, \;Ca^{2+} $Mg2+, Ca2+ or horse serum (25%) decreased its antibacterial activity. DWP20367 was showed rapidly bactericidal activity within 2 to 4 h, and regrowth was not observed even after 24 h incubation at concentrations near the 4-fold of MIC.

• 약학회지
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• 제41권2호
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• pp.233-240
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• 1997

The in vitro antibacterial activity of DWP20418 (1R, 5S, 6S)-6-[1-(R)-Hydroxyethyl)-l-methyl-2-[(2S,4S)-2-(piperazinylcarbonyl)-1-(R)-hydroxyethyl)pyrrolidine-4-thio]carb apen-2-em-3-carboxylic acid), a new carbapenem antibiotic, was compared with those of imipenem (IPM) and meropenem (MEPM). DWP20418 was comparable or slightly more superior to MEPM against gram-positive bacteria, and it showed more potent activity to IPM against gram-negative bacteria. DWP20418 was particularly active against MRSA, and its $MIC_{90}$ of methicillin-susceptible S. aureus, low methicillin-resistant S. aureus and high methicillin-resistant S. aureus were 0.391, 25 and 50 ${\mu}g/ml$, respectively. With a view of $MIC_{90}$, DWP20418 was comparable than the other carbapenems against P. aeruginosa and E. coli isolates. The activity of DWP20418 was not affected in the presence of $Mg^{2+},\;Ca^{2+}$ or horse serum. But inoculum size and alterations in pH of medium affected its antibacterial activity. DWP20418 showed rapidly bactericidal activity within 1h, and regrowth was not observed even incubation of 24hrs at the concentrations near the MIC.

• 접착 및 계면
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• 제9권2호
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• pp.24-31
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• 2008

본 연구에서는 EVA 에멀젼에 내수성 및 기계적 특성을 향상시키기 위하여 금속 이온 가교제인 calcium hydroxide 및 magnesium carbonate를 사용하여 이온성 가교결합을 도입하였다. EVA 에멀젼 필름의 가교밀도, 열적특성, 표면자유에너지 그리고 인장강도, 파단신율 및 인열강도 특성을 고찰하였다. 금속 이온 가교제 양이 증가함에 따라 EVA 에멀젼의 가교밀도는 증가하였고, 이에 내수성과 $T_g$ 값도 증가하였다. 그러나 EVA 에멀젼 필름의 표면에너지 및 기계적 특성들은 다소 다른 거동을 보였다. Calcium hydroxide 0.4% 그리고 magnesium carbonate 0.5%를 첨가한 경우가 EVA 에멀젼에 강한 이온성 가교결합이 형성되어 가장 높은 표면 자유에너지 값과 인장강도 및 인열강도를 보였다. 그러므로 본 연구에서 calcium hydroxide 및 magnesium carbonate와 같은 금속 이온 가교제가 EVA 에멀젼의 내수성과 기계적 물성을 향상시킴을 확인하였다.

• 공업화학
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• 제19권6호
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• pp.661-667
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• 2008

본 연구에서는 LCD 백라이트용 휘도향상 편광필름으로 사용하기 위해, 콜레스테릭 액정(CLC)을 합성하여 네미틱 액정과 혼합한 다음 이들이 충진된 모듈을 제작하였다. 광확산필름에 의해 면광원화된 빛을 통과시킬 때, LCD 백라이트상에서 이들의 투과광 증폭 및 편광능력에 대한 특성을 연구하였다. 합성된 콜레스테릭 액정의 특성은 UV/Visible 스펙트럼과 편광현미경(POM) 등으로 평가하였다. 여러 종류의 선형 카르복실산을 콜레스테롤 분자에 도입하여 콜레스테릭 메소젠 사이의 유연격자를 이루도록 유도하여 각 층에서 일정한 방향성을 유지하도록 하였다. 또한 CLC필름을 적층하여 가시광선대에서 편광능력, 휘도향상 및 투과파장영역을 넓히고 백라이트 유니트의 밝기를 향상시키는 모듈로 적용할 수 있었다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2010년도 춘계학술발표대회
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• pp.43.1-43.1
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• 2010

조직공학의 중요한 요소로 작용하는 scaffold는 여러 가지 필수적인 조건들을 만족시켜야 한다. 대표적인 특징들로는 (1)생분해성 및 비독성, (2)넓은 표면적을 갖는 상호 연결된 내부 다공성 구조, (3)구조적 안정성, (4)세포부착 기질의 제공, (5)낮은 면역 반응성, (6)혈전 형성 억제, (7)친수성, (8)생체 기능성 등을 들 수 있다. 이러한 scaffold가 갖추어야 할 특성 중에서 세포 부착 기질 제공을 위하여 scaffold에 표면 개질을 통한 기능기를 도입하였다. 본 연구에서는 BCP scaffold의 구조적 안정성 부여를 위하여 PCL(polycaprolactone)을 infiltration 하였다. PCL은 소수성의 특징을 갖고 있어 세포와 상호작용 할 수 있는 생물학적 반응기가 없기 때문에 세포와의 친화성이 떨어진다. 세포의 친화성을 높여주기 위해 실리콘의 전구체인 TEOS(tetraethly orthosilicate)를 코팅하고, 그 위에 카복실기(carboxylic acid group)를 도입하였다. 또한 세포의 고정화를 높여주기 위해 fibronectin을 코팅하여 BCP/PCL scaffold의 세포 친화성을 높여주었다. 이와 같이 제조된 고기능성 BCP/PCL scaffold의 내부 구조와 특성을 Micro-CT로 확인하였고, 또한 실리콘 코팅 여부를 확인하기 위하여 SEM-EDS를 통해 관찰하였으며, FT-IR 관찰을 통해 카복실기 도입 여부를 확인 하였다. 또한 생체적합성 평가를 위해 MTT assay, 조골세포의 부착에 미치는 영향을 관찰하기 위해 SEM, 조골세포의 유전자 발현에 미치는 영향을 관찰하기 위해 RT-PCR을 통해 확인 하였다.

• 멤브레인
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• 제28권4호
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• pp.286-295
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• 2018

폴리에틸렌이민(분자량 800)에 다가이온을 갖는 정삼투용 새로운 유도용질을 합성하고 특성을 분석하였다. 폴리에틸렌이민과 메틸 아크릴레이트의 중화반응으로 중간체를 합성하고, KOH로 가수분해하여 수용성의 카복실산 금속염 형태의 폴리에틸렌이민을 합성하였다. NMR, 점도, 삼투압을 측정하여 유도용질의 특성을 평가하였다. 그 염이 유도용질로서 사용할 수 있는지의 여부를 정삼투 실험을 통하여 알아보았다. 유도용질로서 수투과도와 역염 투과도를 측정하여 NaCl과 비교하였다. 정삼투와 나노여과의 혼성공정을 통하여 유도용질의 회수가능성을 보였다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권12호
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• pp.1728-1736
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• 2006

The effects of green tea (Camellia sinensis) waste silage and supplemental polyethylene glycol (PEG) on rumen fermentation and blood components were studied in cattle. Six Holstein steers were fed three diets in a 3${\times}$3 Latin square design, replicated twice. One diet was a control with no added silage, and the other two diets were supplemented (20% of the dry matter) with green tea waste silage either with (PEG) or without PEG (tea). Most of the fermentation parameters including major volatile fatty acids (VFA) were not affected by the diet treatments. The concentrations of high density lipoprotein cholesterol in the PEG group and urea nitrogen in the tea and PEG groups were greater than those in the control before morning feeding. The plasma 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid equivalent concentration was not different before morning feeding, but 3 h after morning feeding, its concentrations in both the tea and PEG groups were higher than in the control. Although the concentration of plasma vitamin A in the animals was not affected by feeding green tea waste silage, the concentrations of plasma vitamin E were significantly higher in the tea and PEG groups than in the control, both before and 3 h after morning feeding. The results from the present study suggest that feeding diets containing 20% of the dietary dry matter as green tea waste silage to Holstein steers has no negative impact on their ruminal fermentation, and increases their plasma antioxidative activity and concentration of vitamin E.

• Journal of Microbiology and Biotechnology
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• 제22권1호
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• pp.69-79
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• 2012

In an ongoing survey of the bioactive potential of microorganisms from Ladakh, India, the culture medium of a bacterial strain of a new Pseudomonas sp., strain ICTB-745, isolated from an alkaline soil sample collected from Leh, Ladakh, India, was found to contain metabolites that exhibited broad-spectrum antimicrobial and biosurfactant activities. Bioactivity-guided purification resulted in the isolation of four bioactive compounds. Their chemical structures were elucidated by $^1H$ and $^{13}C$ NMR, 2D-NMR (HMBC, HSQC, $^1H$,$^1H$-COSY, and DEPT-135), FT-IR, and mass spectroscopic methods, and were identified as 1-hydroxyphenazine, phenazine-1-carboxylic acid (PCA), rhamnolipid-1 (RL-1), and rhamnolipid-2 (RL-2). These metabolites exhibited various biological activities like antimicrobial and efficient cytotoxic potencies against different human tumor cell lines such as HeLa, HepG2, A549, and MDA MB 231. RL-1 and RL-2 exhibited a dose-dependent antifeedant activity against Spodoptera litura, producing about 82.06% and 73.66% antifeedant activity, whereas PCA showed a moderate antifeedant activity (63.67%) at 60 ${\mu}g/cm^2$ area of castor leaf. Furthermore, PCA, RL-1, and RL-2 exhibited about 65%, 52%, and 47% mortality, respectively, against Rhyzopertha dominica at 20 ${\mu}g/ml$. This is the first report of rhamnolipids as antifeedant metabolites against Spodoptera litura and as insecticidal metabolites against Rhyzopertha dominica. The metabolites from Pseudomonas sp. strain ICTB-745 have interesting potential for use as a biopesticide in pest control programs.

• 대한핵의학회지
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• 제28권2호
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• pp.167-171
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• 1994

Ethylcystein dimer (ECD) was synthesized by dimerizatlon of L-thiazolidine-4-carboxylic acid in liquid ammania with sodium metal and successive esterification in ethanolic solution of hydrogen chlorde. The purified product was labeled with $^{99m}Tc$ in the presence of sodium glucarate(pH= 5.6) and stannous chloride. Best result was obtained from the preparation con sisting of 0.1mg ECD, $40{\mu}l$ of 0.4M sodium glucarate (pH=5.6), and $20{\mu}g$ of stannous chloride. The labeling efficiency was 90% with previous condition. The labeled $^{99m}Tc$-ECD was stable at least for 3 hours in PBS(pH=7.4) at room temperature. About 10mCi of $^{99m}Tc$-ECD was injected to normal volunteer, and SPECT image of brain was obtained by triple head camera 10 minutes after inection. The image showed similar distribution of radioactivity in brain with that of HMPAO image.

• Biomolecules & Therapeutics
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• 제5권4호
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• pp.419-425
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• 1997

The pharmacokinetics of DWP20364 (1-cyclopropyl -5-amino-6,8-difluoro-7-(2,7-diazabiclo [3,3,0] oct-4-ene-7-yl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid), a novel fluoroquinolone containing C7-bicyc-talc structure, were compared with those of ciprofloxacin (CPFX) after single intravenous (i.v.) and oral (p.o.) administration to rats using microbiological assay (bioassay). After i.v. administration to rats, the plasma concentrations of the two drugs declined biexponentially. The terminal half-lives (t$_{1}$2$\beta$/) of DWP20364 were 110$\pm$ 13.2 min and 117$\pm$3.09 min after i.v. and p.o. administration, respectively, and they were significantly higher than those of CPFX (45.5$\pm$9.52 min and 48.3$\pm$ 12.1 min, respectively). Similar results were also obtained from plasma concentrations and area under the plasma concentration-time curves. The total body clearance of DWP20364, 7.82$\pm$0.37 ml/min/kg was significantly slower than that of CPFX, 27.3 $\pm$ 11.1 m1/ min/kg. Above data suggested that the antimicrobial activity of DWP20364 could be longer than that of CPFX. The urinary recovery after i.v. and p.o. administration of DWP20364 was significantly lower than those of CPFX suggesting that the effect of DWP20364 on urinary tract infection could be lower than that of CPFX. The serum protein binding values of DWP20364 at 2$\mu$g/ml were apparently 91.5~93.1% in rats and human. DWP20364 was distributed by the order of liver, lung, kidney, sf)leon, heart, muscle and brain collected at 30 min after orally administered.