• Journal of Magnetics
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• 제5권4호
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• pp.120-123
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• 2000

Co-Ni-Fe-N thin films were fabricated by a $N_2$ reactive rf magnetron sputtering method. The nitrogen partial pressure ($P_{N2}$) was varied in the range 0~10% . As$P_{N2}$ increases in this range, the saturation magnetization $B_s$ linearly decreases from 19.8 kG to 14 kG and the electrical resistivity ($\rho$) increases from 27 to 155 $\mu\Omegacm$. The coercivity $H_c$ exhibits the minimum value at 4% $P_{N2}$. The magnetic anisotropy fields ($H_k$) are in the range of 20$\sim$50 Oe. High frequency characteristics of $(Co_{22.2}Ni_{27.6}Fe_{50.2})_{100-x}N_x$ films are excellent in the range of 3$\sim$5% of $P_{N2}$. In particular, the effective permeability of the film fabricated at 4% $P_{N2}$ is 800, which is maintained up to 600 MHz. This film also shows Bs of 17.5 kG, $H_c$/ of 1.4 Oe, resistivity of 98$\mu\Omegacm$ and $H_k$ of about 25 Oe. Also, the corrosion resistance of $(Co_{22.2}Ni_{27.6}Fe_{50.2})_{100-x}N_x$ films was imp roved with increasing N concentration.

• 약학회지
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• 제42권1호
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• pp.59-69
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• 1998

To increase the solubility of quercetin, which is a practically insoluble flavonoid of Ginkgo biloba leaf, the effects of nonaqueous vehicles. Their cosolvents, water-sol uble polymers and modified cyclodextrins (CDs) were observed. Polyethylene glycols, diethyleneglycol monoethyl ether, and their cosolvents with water showed a good solvency toward quercetin. Also the aqueous solutions of povidone, copolyvidone and Cremophor RH 40 was effective in solubilizing quercetin. Complex formation of quercetin with ${\beta}$-cyclodextrin (${\beta}$-CD), dimethyl-${\beta}$-cyclodextiin (DMCD), 2-hydroxypropyl-${\beta}$-cyclodextrin (HPCD) and ${\beta}$-cyclodextrin sulfobutyl ether (SBCD) in water was investigated by solubility method at $37^{\circ}C$. The addition of CDs in water markedly increased the solubility of quercetin with increasing the concentration. AL type phase solubility diagrams were obtained with CDs studied. Solubilizaton efficiency by CDs was in the order of SBCD >> DMCD > HPCD > ${\beta}$-CD. The dissolution rates of quercetin from solid dispersions with copolyvidone, povidone and HPCD were much faster than those of drug alone and corresponding physical mixtures, and exceeded the equilibrium solubility (3.03${\pm}1.72{\mu}$g/ml). The permeation of quercetin through duodenal mucosa did not occur even in the presence of enhancers such as bile salts, but the permeation was observed when the mucus layer was scraped off. This was due to the fact that quercetin had a strong binding to mucin ($58.5{\mu}$g/mg mucin). However rutin was permeable to the duodenal mucosa. The addition of enhancer significantly increased the permeation of rutin in the order of sodium glycocholate.

• Journal of Veterinary Science
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• 제22권1호
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• pp.4.1-4.13
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• 2021

Background: Microsporum canis is a zoonotic disease that can cause dermatophytosis in animals and humans. Objectives: In clinical practice, ketoconazole (KTZ) and other imidazole drugs are commonly used to treat M. canis infection, but its molecular mechanism is not completely understood. The antifungal mechanism of KTZ needs to be studied in detail. Methods: In this study, one strain of fungi was isolated from a canine suffering with clinical dermatosis and confirmed as M. canis by morphological observation and sequencing analysis. The clinically isolated M. canis was treated with KTZ and transcriptome sequencing was performed to identify differentially expressed genes in M. canis exposed to KTZ compared with those unexposed thereto. Results: At half-inhibitory concentration (½MIC), compared with the control group, 453 genes were significantly up-regulated and 326 genes were significantly down-regulated (p < 0.05). Quantitative reverse transcription polymerase chain reaction analysis verified the transcriptome results of RNA sequencing. Gene ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that the 3 pathways of RNA polymerase, steroid biosynthesis, and ribosome biogenesis in eukaryotes are closely related to the antifungal mechanism of KTZ. Conclusions: The results indicated that KTZ may change cell membrane permeability, destroy the cell wall, and inhibit mitosis and transcriptional regulation through CYP51, SQL, ERG6, ATM, ABCB1, SC, KER33, RPA1, and RNP genes in the 3 pathways. This study provides a new theoretical basis for the effective control of M. canis infection and the effect of KTZ on fungi.

• 한국산학기술학회논문지
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• 제20권7호
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• pp.265-271
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• 2019

본 논문의 목적은 기존의 에틸렌기반 폴리머 사용 배합인 투수 콘크리트 단점을 개선하고자, 아크릴 폴리머를 적용함으로써 개선된 도로 포장 재료로써 활용하기 위한 기초자료를 제시하고 한다. 기존의 에틸렌 폴리머 기반 투수 콘크리트 재료를 선정하고, 아크릴 폴리머를 혼입하여 배합 설계하여 비교 평가하였다. 시험결과, 기존 에틸렌 기반 폴리머 투수 콘크리트 배합 경우 큰 공극률이 발생하여 압축강도 증진이 미약한 결과를 나타냈었고, 아크릴 폴리머 기반 투수 콘크리트 배합 경우 KS에서 규정하고 있는 차도용 28일 압축강도 24MPa을 만족하였다. 휨강도인 경우, 아크릴 폴리머 기반 투수 콘크리트 배합 강도가 우수하였으며, 투수 계수는 모든 변수에서 기준인 0.1(mm/s) 이상으로 측정되었다. 흡수율의 경우 모든 변수에서 1% 이하로 측정되었고, 동탄성계수 측정결과, 아크릴 폴리머배합특성의 경우 120 Cycle 이상 측정을 유지할 수 있었고, 다른 배합의 경우 80 Cycle 이상 유지하지 못하였다. 따라서 기존의 에틸렌 폴리머 기반보다 아크릴 폴리머를 적용함으로써, 내구성 향상에 효과적인 것으로 판단된다.

• 멤브레인
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• 제29권5호
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• pp.252-262
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• 2019

서로 다른 술폰화 정도에 따라 sulfonated star branched poly(styrene-b-butadiene-b-styrene) triblock copolymer (SSBS)가 합성되었다. 술폰화된 butadiene block은 FT-IR spectroscopy로 확인할 수 있다. 술폰화 정도를 측정 비교하기 위해서 산-염기 적정을 통하여, ion exchange capacity (IEC)를 계산하였다. 술폰화된 SSEB 전해질막은 높은 water uptake와 proton conductivity를 보였다. 실온에서 25 mol% 술폰화된 SSBS는 0.114 S/cm라는 높은 값을 나타냈으며, 이는 Nafion과 비슷한 수치였다. 일정한 상대 습도에서 온도의 증가는 현저하게 높은 수소이온전도도를 나타냄을 알 수 있었다. 모든 술폰화된 막은 Nafion과 비교했을 때 낮은 methanol 투과도를 보여주었다. AFM을 이용하여 술폰화된 전해질막의 구조는 이른바 분리된 나노구조의 미세상과 ionic channel의 접속으로 이루어졌음을 확인할 수 있었다.

• 동의생리병리학회지
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• 제34권4호
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• pp.184-190
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• 2020

This study was performed to find antibacterial substances contained in Scutellariae Radix (SR) using a systems pharmacological analysis method and to establish an effective strategy for the prevention and treatment of infectious diseases. Analysis of the main active ingredients of SR was performed using Traditional Chinese Medicine Systems Pharmacology (TCMSP) Database and Analysis Platform. 36 active compounds were screened by the parameter values of Drug-Likeness (DL), Oral Bioavailability (OB), and Caco-2 permeability (Caco-2), which were based on the drug absorption, distribution, metabolism, and excretion indicators. The UniProt database was used to obtain information on 159 genes associated with active compounds. The main active compounds with antibacterial effects were wogonin, β-sitosterol, baicalein, acacetin and oroxylin-A. Target proteins associated with the antibacterial action were chemokine ligand 2, interleukin-6, tumor necrosis factor, caspase-8,9 and mitogen-activated protein kinase 14. In the future, systems pharmacological analysis of traditional medicine will be able to make it easy to find the important mechanism of action of active substances present in natural medicines and to optimize the efficacy of medicinal effects for combinations of major ingredients to help treat certain diseases.

• The Plant Pathology Journal
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• 제37권6호
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• pp.533-542
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• 2021

Chitosan has been considered an environmental-friendly polymer. However, its use in agriculture has not been extended yet due to its relatively low solubility in water. N-Methylene phosphonic chitosan (NMPC) is a water-soluble derivative prepared by adding a phosphonic group to chitosan. This study demonstrates that NMPC has a fungicidal effect on the phytopathogenic fungus Fusarium solani f. sp. eumartii (F. eumartii) judged by the inhibition of F. eumartti mycelial growth and spore germination. NMPC affected fungal membrane permeability, reactive oxygen species production, and cell death. Also, this chitosan-derivative exerted antifungal effects against two other phytopathogens, Botrytis cinerea, and Phytophthora infestans. NMPC did not affect tomato cell viability at the same doses applied to these phytopathogens to exert fungicide action. In addition to water solubility, the selective biological cytotoxicity of NMPC adds value in its application as an antimicrobial agent in agriculture.

• Journal of the Korean Wood Science and Technology
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• 제31권1호
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• pp.52-60
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• 2003

액체암모니아 처리 침·활엽수 소시편의 물리적 성질을 무처리와 비교하였다. 처리시간은 4와 8시간으로 하였다. 동일한 환경에서 처리재의 평형함수율은 무처리재보다 항상 높았으나 전건 후에는 차이를 나타내지 않았다. 암모니아 처리를 오래할수록 방사방향과 접선방향으로 수축이 일어났으나 섬유방향에는 변화가 없었다. 또 처리시간이 길수록 초음파 전달속도는 감소하고 밀도는 증가하였다. 따라서 동탄성계수는 감소함을 보였다. 밤나무의 가소화는 증기처리가 액체 암모니아 처리보다 효과 있음과 인사이징이 침·활엽수 모두 액체 암모니아 침투성을 높이지 못했음이 밝혀졌다. 액체 암모니아 처리는 5mm두께 침엽수 시편에서 제일 좋은 가소화 효과를 보였다. 상대유전율과 열전달계수도 측정하여 처리재와 무처리재를 비교하였다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.84-84
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• 2001

The heartwood of Rhus verniciflua has been known to be effective for lingering intoxication and diabetes mellitus and rheumatoidal arthritis in traditional folk medicine in Korea. We have previously reported that antimutagenic effect of flavonoids derived from the heartwood extract of R. verniciflua, and sulfuretin was the active component. Recently, we have demonstrated that sulfuretin could be an anti-inflammatory principle of the R. verniciflua heartwood partially dependent on cyclooxigenase-inhibitory activity. The present study was undertaken to demonstrate the anti-rheumatoidal arthritis effect of the R. verniciflua heartwood extract, its EtOAc fraction and the main flavonoids, sulfuretin and fustin. All the test samples showed variably significant inhibitory effects on hind paw edema induced by Freund's complete adjuvant reagent (FCA reagent). Sulfuretin treatment with 10 mg/kg (i.p.) for seven days showed the inhibitory effect of 54.2${\pm}$3.0%, Similar trends in RA- and CRP tests, vascular permeability test and trypsin inhibitor test were also found. In addition, no dead mouse was found even when the dose was increased up to 5,000 mg/kg (i.p.). Treatment with 250-1,500 mg/kg on normal rats did not show any marked toxicological significances in the tests of body weight gain, wet weight of organs and hepatic functions. These results suggested that the heartwood of R. verniciflua could be an adequate crude drug for rheumatoidal arthritis with an active component of sulfuretin. The toxicological safety of the heartwood of R, verniciflua is contrasted to known severe allergenic action of the stem bark or its exudate.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2000년도 International Symposium on Magnetics The 2000 Fall Conference
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• pp.492-499
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• 2000

Co-Ni-Fe-N thin films were fabricated by a N$\sub$2/ reactive rf magnetron sputtering method. The nitrogen partial pressure (P$\sub$N2/) was varied in the range of 0∼10%. As P$\sub$N2/ increases in this range, the saturation magnetization (B$\sub$s/) linearly decreases from 19.8 kG to 14 kG and the electrical resistivity ($\rho$) increased from 27 to 155 ${\mu}$$\Omega$cm. The coercivity (H$\sub$c/) exhibits the minimum value at 4% of P$\sub$N2/. The magnetic anisotropy (H$\sub$k/) are in the range of 20∼50 Oe. High frequency characteristics of (Co$\sub$22.2/Ni$\sub$27.6/Fe$\sub$50.2/)$\sub$100-x/N$\sub$x/ films are excellent in the range of 3∼5% of P$\sub$N2/. Especially the effective permeability of the film fabricated at 4% of P$\sub$N2/ is 800, which is maintained up to 600 MHz. This film also shows Bs of 17.5 kG, H$\sub$c/ of 1.4 Oe, resistivity of 98 $\Omega$cm and H$\sub$k/ of about 25 Oe. Also, the corrosion resistance of (Co$\sub$22.2/Ni$\sub$27.6/Fe$\sub$50.2/)$\sub$100-x/N$\sub$x/ were improved with the increase in N concentration.