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Antimicrobial Hydrogel Contact Lens Containing Alginate

  • Lee, Hyun-Mee;Kim, Jong-Ki;Cho, Tae-Sub
    • Bulletin of the Korean Chemical Society
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    • v.32 no.12
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    • pp.4239-4243
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    • 2011
  • Biocompatible hydrogels from 2-hydroxyethyl methacrylate (HEMA) monomer containing various amount of alginate in the presence and absence of hydrophilic methacrylic acid (MAA) were synthesized in order for biomedical application. The antimicrobial effect and interaction with proteins for hydrogels were investigated in this study. MAA was introduced because it was expected to increase the amount of water content in the polymer which is an important factor for biocompatibility, and alginate was expected to enhance the antimicrobial activity. The antimicrobial effect against S. aureus and E. coli increased for all hydrogels as the amount of alginate and MAA contained. Presence of MAA further enhances the antimicrobial effect. Amount of adsorption of bovine serum albumin (BSA) increased with increasing concentration of alginate whether MAA was present or not. Contrarily, the amount of lysozyme was not affected with increasing alginate concentration in the absence of MAA, while it decreased in the presence of MAA.

Capping of Silybin with β-Cyclodextrin Influences its Binding with Bovine Serum Albumin: A Study by Fluorescence Spectroscopy and Molecular Modeling

  • Natesan, Sudha;Sowrirajan, Chandrasekaran;Dhanaraj, Premnath;Enoch, Israel V.M.V.
    • Bulletin of the Korean Chemical Society
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    • v.35 no.7
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    • pp.2114-2122
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    • 2014
  • The association of silybin with ${\beta}$-cyclodextrin and its influence on silybin's binding with bovine serum albumin are reported. The stoichiometry, binding constant, and the structure of silybin-${\beta}$-cyclodextrin inclusion complex are reported. The titrations of silybin with bovine serum albumin in the absence and presence of ${\beta}$-cyclodextrin are carried out and the differences in binding strengths are discussed. Molecular modeling is used to optimize the sites and mode of binding of silybin with bovine serum albumin. F$\ddot{o}$rster resonance energy transfer is calculated and the proximity of interacting molecules is reported in the presence and absence of ${\beta}$-cyclodextrin.

First Larvae of Lebbeus comanthi and Thor amboinensis(Decapoda: Hippolytidae) Hatched in the Laboratory

  • Yang, Hoi Jeong;Okuno, Junji
    • Animal cells and systems
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    • v.8 no.1
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    • pp.19-25
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    • 2004
  • The decapodid stage of Lebbeus comanthi Hayashi and Okuno and the first zoea of Thor amboinensis (De Man) are described based on laboratory-hatched eggs from females collected from Japan. The decapodid stage of L. comanthi is readily distinguished from that of L. groenlandicus by the carapace without anteroventral denticle and tooth behind rostrum, the absence of the antennal spine, the four-segmented outer flagellum of the antennule, the absence of the palp of the mandible, and the telson with posterior margin con caved medially and without dorsolateral spine. The carapace with anteroventral denticle and the third abdominal somite distinctly curved in lateral view distinguish the first zoea of T. amboinensis from that of T. dobkini Chace and T. floridanus Kingsley. Larval characters of the genus Thor are summarized.

Hirschsprung's Disease (Hirschsprung씨 병)

  • Lee, Nam-Hyuk
    • Journal of Yeungnam Medical Science
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    • v.24 no.1
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    • pp.11-23
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    • 2007
  • Hirschsprung's disease is one of the most common causes of intestinal obstruction in neonates and infants. The underlying pathology of this disease is the absence of the ganglion cells in both the myenteric (Auerbach's) plexus and the submucosal (Meissner's) plexus. Since Hirschsprung's report in 1886, there have been thousands of papers on Hirschsprung's disease but the cause of the absence of the ganglion cells has not been identified. Hirschsprung's disease can be successfully treated with the Swenson, the Duhamel, and the Soave operations even though the pathogenesis is unknown. With the recent progress of molecular biology and genetics, a more detailed approach to the pathogenesis of Hirschsprung's disease can be undertaken. In addition, there have been recent developments in the surgical approach. In this review, recent advances in surgery for Hirschsprung's disease are presented.

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Conserved Roles of MonA in Fungal Growth and Development in Aspergillus Species

  • Son, Ye-Eun;Park, Hee-Soo
    • Mycobiology
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    • v.47 no.4
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    • pp.457-465
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    • 2019
  • MonA is a subunit of a guanine nucleotide exchange factor that is important for vacuole passing and autophagy processes in eukaryotes. In this study, we characterized the function of MonA, an orthologue of Saccharomyces cerevisiae Mon1, in the model fungus Aspergillus nidulans and a toxigenic fungus A. flavus. In A. nidulans, the absence of AnimonA led to decreased fungal growth, reduced asexual reproduction, and defective cleistothecia production. In addition, AnimonA deletion mutants exhibited decreased spore viability, had reduced trehalose contents in conidia, and were sensitive to thermal stress. In A. flavus, deletion of AflmonA caused decreased fungal growth and defective production of asexual spores and sclerotia structures. Moreover, the absence of monA affected vacuole morphology in both species. Taken together, these results indicate that MonA plays conserved roles in controlling fungal growth, development and vacuole morphology in A. nidulans and A. flavus.

Immobilization Imparts Stability to Watermelon Urease to Work in Water Miscible Organic Media

  • Prakash, Om;Upadhyay, Lata Sheo Bachan
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.11 no.2
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    • pp.140-145
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    • 2006
  • The behaviour of alginate immobilized and soluble watermelon (Citrullus vulgaris) urease in water miscible organic solvents like, acetonitrile, dimethylformamide (DMF), ethanol, methanol, and propanol is described. The organic solvents exhibited a concentration dependent inhibitory effect on both the immobilized and the soluble urease in the presence of urea. Pretreatment of soluble enzyme preparations with organic solvents in the absence of substrate for 10 min at $30^{\circ}C$ led to rapid loss in the activity, while similar pretreatment of immobilized urease with 50% (v/v) of ethanol, propanol, and acetonitrile was ineffective. Time-dependent inactivation of immobilized urease, both in the presence and in the absence of urea, revealed stability for longer duration of time even at very high concentration of organic solvents. The soluble enzyme, on the other hand, was rapidly inactivated even at fairly lower concentrations. The results suggest that the immobilization of watermelon urease in calcium alginate make it suitable for its application in organic media. The observations are discussed.

Verification of AGB (alpha-glucosidase biosynthesis) Bacterial Bioassay of Metal Toxicity and Inhibition Effect of Fulvic Acid (EA) (박테리아(E. Coli)의 AGB (alpha-glucosidase biosynthesis)를 이용한 중금속의 독성시험과 풀빅산에 의한 독성 억제효과)

  • Kim Jae Hyoun;Kim Myung Gill;Om Ae Son
    • Environmental Analysis Health and Toxicology
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    • v.19 no.1
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    • pp.25-32
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    • 2004
  • Aim of the present study was the development of a bioassay which enables the detection of toxic effects of heavy metal ions to a bacterium, Escherichia coli. Inhibition effects of the metals on growth rates of the bacterium were studied in the absence or presence of fulvic acid. This method does not clearly differentiate among metals, but does detect overall AGB inhibition rate (toxicity) for 5 different heavy metals. The toxicity of the metals in the absence of fulvic acid in the same testing conditions was significantly increased in following order: Hg < Pb, Zn < Cd < Cu, whereas the inhibition rate (toxicity) in the presence of FA was shown to be increased In following order: Cd < Pb, Hg < Cu < Zn. The results of the present study indicate that this simple and fast biomonitoring assay with direct exposure of E coli. might be a valuable supplement to analytical methods of contaminated media.

Implementation of Presence and Absence of Blocking Effects: A Categorial Grammar Approach to Chinese and Korean

  • Lee, Yong-Hun
    • Proceedings of the Korean Society for Language and Information Conference
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    • 2007.11a
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    • pp.275-284
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    • 2007
  • Among the languages that allow long-distance reflexives, some languages have blocking effects, whereas others don't. The goal of this paper is to provide computational algorithms that can handle presence and absence of blocking effects of long-distance reflexives. We will examine the blocking effects in Chinese and Korea and develop computational algorithms for handling blocking effects in those two languages. The algorithms will be developed by incorporating Chierchia's Binding Theory into Steedman's Combinatory Categorial Grammar (CCG). Through the analyses and implementations, this paper illustrates how blocking effects can be implemented computationally.

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effect of Nif A Overproduction on the Improvement of Nitrogenase Activity of Klebsiella oxytoca Strains (Nif A의 Overproduction에 의한 Klebsiella oxytoca 균주의 질소 고정력 증진 효과)

  • 서현창;유익동
    • The Korean Journal of Food And Nutrition
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    • v.5 no.2
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    • pp.137-143
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    • 1992
  • As a research for developing biofertilizers, Klebsiella oxytoca, an associative nitrogen fixer in the rhizosphere of rice plant in the soil of paddy field, was subjected to molecular breeding. The results obtained were as followings. 1). By transforming pbIC71A, Nif A overproducing plasmid, into Klebsiella oxytoca NGl3, Klebsiell6f oxytoca SH3l, and Klebsiella oxytoca SH161, nitrogenase activities in the absence of nitrogen source in the medium were increased 6.4, 17.2, and 13.5 times, respectively, in comparison with the parent strains. 2). Nitrogenase activity of Klebgiella oxytoca NGl3, Klebsiella oxytoca SH3l, and Klebsiella oxytoca SH161 was completely repressed In the presence of 15mM NH4+. But, nitrogenase activities of Klebsiella oxytoca NGl3/PMC71A, Klebsiella oxytoca SH3l /PMC71A, and Klebsiella oxytoca SH 161/pMC714 harboring PMC71A, were 13.7%, 7.7%, and 6.2% of the nitrogenase activities in the absence of nitrogen source in the medium, respectively.

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A Study on the Effect of Resident Participatory Education Program in Fishing Village -Focused on Improvement of Community Attachment and Sense of Community- (어촌마을 주민참여 교육 프로그램 효과성 분석에 관한 연구 -지역애착도와 공동체의식 향상을 중심으로-)

  • Park, Hye Eun
    • Journal of Korean Society of Rural Planning
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    • v.19 no.1
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    • pp.137-147
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    • 2013
  • The purpose of this study is to analyze the effect of "resident participatory education programs". This study methods was that applied this education programs to the residents of the fishing village after develop of education programs, and was surveyed to ninety five residents of these. As a result of the survey, "community attachment" and "sense of community" showed statistically significant differences from consciousness before and after education. Also, difference of residents consciousness according to the presence or absence of an education showed the same trend too. And, If in the presence or absence of the educational experience, residents consciousness was improved after the education programs. In other words, an education programs applied to in this study can be said to effective to that raise awareness of the residents. And this can be said to contribute in empowerment too.