• Title/Summary/Keyword: Critical Science Research

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Purification and Identification of Apoptosis Modulator Pipernonaline from Piper longum Linn. against Prostate Cancer Cells (필발(Piper longum Linn.)로부터 전립선암 세포사멸물질 pipernonaline의 분리 및 동정)

  • Kim, Kwang-Youn;Kim, Yun-Jin;Lee, Wan;Yu, Sun-Nyoung;Cho, Hyo-Jin;Lee, Sun-Yi;Lee, Han-Seung;Sohn, Jae-Hak;Oh, Hyuncheol;Ahn, Soon-Cheol
    • Journal of Life Science
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    • v.19 no.5
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    • pp.671-675
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    • 2009
  • Prostate cancer has been a critical health problem due to an increase of prostate cancer-related deaths worldwide. Also, a frequent treatment option for prostate cancer is androgen ablation, but this treatment has a limited scope, especially for hormone-refractory cancer. There is an urgent need for the identification of alternative therapeutic strategies for prostate cancer. Previously, over one hundred species of dried-plant methanol extracts were tested for inhibitory effects on proliferation. One of them, Piper longum Linn. was selected based on its potent anti-proliferation effect. The dried root of P. longum Linn. was extracted with 100% methanol for 2-3 days and its extract was fractionated using chloroform. The chloroform layer was then subjected to column chromatography on silica gel, reverse phase-18 (RP-18) and Sephadex LH-20, in turn. Finally, the pure compound was obtained and identified as pipernonaline by NMR spectroscopic and physico-chemical analysis. In this study, anti-proliferation and cell cycle arrest effects of pipernonaline on human prostate cancer PC-3 cells were investigated using the MTT and PI staining, respectively. Our findings suggest that pipernonaline represents a dose-dependent growth inhibition pattern on PC-3 cells and, moreover, its growth inhibition is associated with sub-G1 and G0/G1 cell cycle accumulation in PC-3 cells. Also, these results provide an anticancer candidate for human prostate cancer.

A Critical Study on Validity of the Present Purpose of the Public Library Defined in the Korean Library Act ('도서관법(圖書館法)' 중(中) '공공도서관(公共圖書館)의 목적(目的)'에 대한 비판적(批判的) 고찰(考察))

  • Choi, Sung-Jin
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.2 no.1
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    • pp.132-177
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    • 1974
  • Toe public library may perform a social good only when its objectives are adequate to the community's needs. The present purpose of the public library in the Korean Library Act has no direct concern for our social needs from its very beginning because it was not created in response to our social needs but transplanted from American principles. It is, therefore. difficult to expect socially useful output of our public library programs under the present purpose which may be inadequate to our social tradition and needs. This study purposes to examine validity of the present purpose of the public library in the Korean Library Act, in the light of our community needs and our own library tradition. The methods employed to achieve the purpose of the study are (1) to survey needs of the library frequenters through questionnaire, and interviews with the public librarians in Seoul, (2) to gather the statistical data relevant to, and supporting, the hypothesis, and (3) to compare our social background with that of the United States of which the American purpose, a model for our present purpose, came out. The conclusion is as follows: A. The idea to induce people to pull themselves upward by providing for all the members of the community access to the world's best books shelved in the public library should be abandoned. The reasons are (1) that the idea is alien in our public library tradition, (2) that little demand of the community goes with the idea, and (3) that reading outside the library has come into wide practice, thanks to recent increase in individual income and that in publications. B. That the public library maintains fiction and other recreational reading materials is meaningless in the light of the community needs. These are the two explanations supporting the thesis. (1) The "uplift" theory has proved inoperative and people apparently do not progress from, light fiction to more respectable fare. (2) The conviction that fiction and other recreational reading materials keep the middling classes from the "vicious" entertainments maintaining order in the community by giving them a harmless source of recreation has lost its significance as the modern society provides a number of choices in recreation: television is an obvious example. C. The nature of the informational needs of the community has radically changed, so radically as to require substantial changes in the outlook, collections, and services of the public library, which is :slow in adopting itself to the new social surroundings in Korea. D. 92.2 per Cent of the present frequenters of the public library are high school and college students. Since the library is to meet the existing community needs it should turn its attention to the student group, and develop the means to serve it better, not the "theoretical group of specialists who do not come to "the public library. E. In revision of the purpose of the public library, priority of each objective should be given. The priorities in the last analysis are research and information. culture, recreation in that order.

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Research Trends for Nanotoxicity Using Soil Nematode Caenorhabditis elegans (토양선충 Caenorhabditis elegans를 이용한 나노독성 연구동향)

  • Kim, Shin Woong;Lee, Woo-Mi;An, Youn-Joo
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.12
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    • pp.855-862
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    • 2012
  • Caenorhabditis elegans, a free-living nematode mainly found in the soil pore water, roles the critical function in trophic levels, energy flow, and decomposition in soil ecosystem. C. elegans is commonly used species to test soil toxicity. Recently, they are employed broadly as a test organism in nanotoxicology. In this study, a review of the toxicity of nanomaterials for C. elegans was presented based on SCI (E) papers. The nanotoxicity studies using C. elegans have been reported in 20 instances including the mechanism of toxicity. Most studies used K-medium, S-medium, and NGM (Nematode Growth Medium) plate as an exposure medium to test toxicity of nanoparticles. The effects observed include anti aging, phototoxicity, genotoxicity, and dermal effects on C. elegans exposed to nanoparticles. We found that the toxic mechanisms were related with various aspects such as lifespan abnormality, oxidative stress, distribution of particles on inter-organisms, and stress-related gene analysis. C. elegans has advantage to test toxicity of nanoparticles due to various cellular activities, full genome information, and easy observation of transparent body. C. elegans was considered to be a good test species to evaluate the nanotoxicity.

Impact of Meteorological Wind Fields Average on Predicting Volcanic Tephra Dispersion of Mt. Baekdu (백두산 화산 분출물 확산 예측에 대기흐름장 평균화가 미치는 영향)

  • Lee, Soon-Hwan;Yun, Sung-Hyo
    • Journal of the Korean earth science society
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    • v.32 no.4
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    • pp.360-372
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    • 2011
  • In order to clarify the advection and dispersion characteristics of volcanic tephra to be emitted from the Mt. Baekdu, several numerical experiments were carried out using three-dimensional atmospheric dynamic model, Weather and Research Forecast (WRF) and Laglangian particles dispersion model FLEXPART. Four different temporally averaged meteorological values including wind speed and direction were used, and their averaged intervals of meteorological values are 1 month, 10 days, and 3days, respectively. Real time simulation without temporal averaging is also established in this study. As averaging time of meteorological elements is longer, wind along the principle direction is stronger. On the other hands, the tangential direction wind tends to be clearer when the time become shorten. Similar tendency was shown in the distribution of volcanic tephra because the dispersion of particles floating in the atmosphere is strongly associated with wind pattern. Wind transporting the volcanic tephra is divided clearly into upper and lower region and almost ash arriving the Korean Peninsula is released under 2 km high above the ground. Since setting up the temporal averaging of meteorological values is one of the critical factors to determine the density of tephra in the air and their surface deposition, reasonable time for averaging meteorological values should be established before the numerical dispersion assessment of volcanic tephra.

Nitric Oxide on the MMP-2 expression by human gingival fibroblasts (치은섬유아세포의 MMP 발현에 대한 Nitric Oxide의 영향)

  • Shin, In-Sik;Yoon, Sang-Oh;Chung, Hyun-Ju;Koh, Jung-Tae
    • Journal of Periodontal and Implant Science
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    • v.33 no.2
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    • pp.277-288
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    • 2003
  • It has been suggested that increased number and activity of phagocytes in periodontitis lesion results in a high degree of reactive oxygen species (ROS) such as superoxide anion, hydrogen peroxide, nitric oxide and peroxynitrite. There are few reports on the relationship between ROS and MMPs expressions in gingival fibroblast. We studied to elucidate whether and how ROS, especially nitric oxide affects the MMP expression. Human gingival fibroblasts and HTl080 cells (human fibrosarcoma sell line as reference) were grown in DMEM supplemented with 10 mM HEPES, 50 mg/L gentamicin, and 10% heat inactivated fetal bovine serum with addition of various reactive oxygen species (ROS). Culture media conditioned by cells were examined by gelatin zymography. HT1080 cells expressed proMMP-2 and proMMP-9, but human gingival fibroblasts (HGF) produced only proMMP-2. Hydrogen peroxide upregulated MMP-9 expression in HT1080 cells, whereas in human gingival fibroblast SNP treatment showed marked increase in MMP-2 level compared to other ROS. These results suggest that the effects of ROS on MMPs expressions are cell-type specific. RT-PCR for MMP-2 and TIMP-2 m-RNA were performed using total RNA from cultured cells under the influence various kinase inhibitors. In HT1080 cells, treatment with FPTI III (Ras processing inhibitor) and LY294002 (PI3-kinase inhibitor) resulted in inhibition of MMP-2 and MMP-9 expressions, suggesting that Ras/P13-kinase pathway is important for MMPs expression in HT1080 cells. In gingival fibroblasts, treatment with FPTI III and PDTC (NF-kB inhibitor) showed marked decrease in MMP-2 regardless of the of SNP , suggesting that Ras/NF-kB could be the key pathway for NO-induced MMP-2 expression in gingival fibroblasts. This study showed that ROS, especially nitric oxide, could be the critical mediator of periodontal disease progression through control of MMP-2 expression in gingival fibroblasts possibly via Ras/NF-kB pathway.

Trends of Thermochemical Technology for the Recovery of Phosphorus from Sewage Sludge Ash (열화학적 방법에 의한 하수 슬러지 소각재에서의 인 회수 기술 동향)

  • Jeon, Seulki;Shin, Hyuna;Kim, Dong-Jin
    • Clean Technology
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    • v.24 no.2
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    • pp.87-98
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    • 2018
  • Phosphorus (P) is an essential and irreplaceable element for all living organisms, and it is widely used as a fertilizer. Unfortunately, it is estimated that phosphate reservoir is depleted within about 100 years. Sewage sludge ash (SSA) is an alternative resource for P recovery because of its high P content. However, SSA cannot be directly used as a fertilizer due to heavy metals in it and low P bioavailability. Thermochemical treatment with Cl donor is known to reduce heavy metal contents and increase P bioavailability of SSA. Literature review on thermochemical technologies of SSA for the reduction of heavy metals and bioavailability enhancement has been carried out to estimate the status of current P recovery technology and to develop strategic future research plan for P recovery. The review showed that $CaCl_2$ and $MgCl_2$ were the most effective Cl donors and reaction temperature (< $1000^{\circ}C$) was the critical operation condition for the reduction. The removal efficiency depends on the species of heavy metals. Thermochemical technology of SSA for P recovery showed the possibility of commercial application in the near future to overcome the coming crisis of human sustainability by P depletion, but it needs cost effectiveness and more ecofriendly process to reduce energy consumption.

Using Logistic Regression for Determining the Factors Affecting Bidding Success in World Bank's International Consulting Projects in Indonesia (로그 회귀분석을 이용한 해외 엔지니어링 사업의 낙찰 성공 요인 분석 - 세계은행의 인도네시아 사업을 중심으로-)

  • Yu, Youngsu;Shin, Byungjin;Koo, Bonsang;Han, Seungheon
    • Korean Journal of Construction Engineering and Management
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    • v.19 no.1
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    • pp.80-89
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    • 2018
  • World Bank projects enable Korean engineering firms to enter new markets and diversify their portfolio. These firms need to understand the critical factors for bidding success in such projects. The World Bank publishes as open records all their bidding history data in their open database. This provides an opportunity to identify empirically the factors that determine which firms on chosen. This research collected relevant bid data, focusing on Indonesia, to perform a logistic regression with the goal of statistically identifying significant factors that result in bidding success. Results showed that work experience, being included in a consortium, and having a local partner positively affected winning a bid. On the other hand, having a local competitor of the recipient country negatively impacts the chances of attaining a bid. Commensurately, Korean engineering firms need to increase their work experience in internationally recognized projects, and include a local partner as a joint venture partner to increase their chances, while refrain from conventional projects that can be performed by local engineering firms.

Growth Inhibition Effects of Cancer Cell Lines by Gloiopeltis furcata Fractions in Vitro (불등가사리 분획물의 암세포 성장 억제 효과)

  • Park, Soung-Young;Jung, Bok-Mi;Choi, Yung-Hyun;Bae, Song-Ja
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.6
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    • pp.771-775
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    • 2005
  • The growth inhibitory effects on human cancer cell lines provide useful information regarding critical cellular targets. Reports on cytotoxicity of Gloiopeltis furcata (GF) to human cancer cell lines are conflicting. This study was performed to investigate the effects of cytotoxicity and quinone reductase activity of Gloiopeltis furcata on the human cancer cells. The four partition layers of methanol extracts (GFM) which are hexane (GFMH), methanol (GFMM), butanol (GFMB) and aquous (GFMA) were screened for their cytotoxic effects on HepG2, HeLa, MCF-7, HT-29, and normal liver cell lines. The GFMM showed the strongest growth inhibition effect on all cell lines we used. the GFMM showed the highest induction activity of quinone reductase on HepG2 cells among the other partition layers.

Problems in Quantification of Adequacy of Academic Library Collections -Critical Analysis of Standards for Academic Libraries in the U.S.- (종합대학 도서관장서의 적정량기준 설정에 관한 고찰 -미국의 종합대학도서관기준을 중심으로-)

  • Chung Young Sun
    • Journal of the Korean Society for Library and Information Science
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    • v.8
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    • pp.183-207
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    • 1981
  • Library standards have been the source of considerable controversy, whereas many problems are involved in developing stardard for university library collections. For evaluation purposes, standards should be precise, quantifiable and measurable. In the United States, however, standards for academic libraries are limited to qualitative statements and principles. Quantitative standards, when given, are ususally related to the number of population in the institution being served, or the prescribed quantitative objectives are often arbitrarily formulated by value judgements. The study in this paper attempts to explain the problems involved in developing quantitative standard for academic library collections. Two problems facing in the formulation of the optimal size of collection are identified. One is the theoretically faulty concept of adequacy of collection to meet the situations of diversity of university libraies, and the other is the difficulties in quantification and measurement, along with the lack of concept of adequacy of collection. However, quantification of adequate size of collection is proved to be useful on the pratical level, even though not valid theoretically. ACRL, Clapp/Jordan and Voigt developed formulas or models for setting the optimal size of a library collection for any particular university library. The main purpose of this study is the analysis of the above formulas. ACRL standard was drawn from obervation and analysis of statistcs in leading library collections. In academic field, this judgement appears to have been based on the assumption that a high-grade institution would be apt to have a good library collection. This study criticizes ACRL standard for its failure to include some determinants of measurements, and points out the limitations of the standard. In contrast. Clapp/Jordan developed a formula rather scientifically based upon bibliographical sources. This is similarly empirical but has the advantage of bringing into play the elements which make universities diverse in nature. Both ACRL and Clapp/Jordan formulas share two major defects. (1) the specific subject needs of the collection are not indiacted directly, and (2) percentage rate of growth is an indicator in measuring the potential utility of a collection. Thus both formulas failed to provide a basis for meaningful evaluation. Voigt further developed a model for determining acquisition rates for currently published materials based on bibliographic technique. Voigt model encourages experimentation with different programs and different allocations of input resources, designed to meet the needs of the library's particular population. Standard for university library collections can be formulated in terms of input(traditional indicator), or additionally, in terms of output(cost-effectiveness). Cost effectiveness is expressed as user satisfaction, ability to provide wanted materials within a reasonable time period. Thus simple quantitative method does not cover all the situations of diversity of university library collections, nor measures the effectiveness of collections. Valid standard could not be established without further research.

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Biological Roles of the Glycan in the Investigation of the Novel Disease Diagnosis and Treatment Methods (신개념 질병 진단 및 치료 연구에 있어서의 당사슬의 생물학적 역할)

  • Kim, Dong-Chan
    • Journal of Life Science
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    • v.28 no.11
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    • pp.1379-1385
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    • 2018
  • Glycans are attached to proteins as in glycoproteins and proteoglycans. They are found on the exterior surface of cells. O- and N-linked glycans are very common in eukaryotic cells but may also be found in prokaryotes. The interaction of cell surface glycans with complementary glycan binding proteins located on neighboring cells, other cell types, pathogens like virus, or bacteria is crucial in biologically and biomedically important processes like pathogen recognition, cell migration, cell-cell adhesion, development, and infection. Their implication in pathological condition, suggests an important role for glycans as disease markers. In addition, a great amount of research has been shown that appropriate glycosylation of a recombinant therapeutic protein is critical for product solubility, stability, pharmacokinetics and pharmacodynamics, bioactivity, and safety. Besides, cancer-associated glycosylation changes often involve sialic acid in glycan branch which play important roles in cell-cell interaction, recognition and immunological response. This review aims at giving a comprehensive overview of the glycan's biological function and describing the relevance among the glycosylation, disease diagnosis and treatment methods. Furthermore, the high-throughput analytic methods available to measure the profile changing patterns of glycan in the blood serum as well as possible underlying biochemical mechanisms.