• Title/Summary/Keyword: Bio-nano

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Solid Phase Synthesis of Lysine-exposed Peptide-Polymer Hybrids by Atom Transfer Radical Polymerization (ATRP를 이용한 Lysine 말단기를 가진 펩타이드-고분자 하이브리드 합성)

  • Ha, Eun-Ju;Kim, Mijin;Kim, Jinku;An, Seong Soo A.;Paik, Hyun-Jong
    • Polymer(Korea)
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    • v.38 no.4
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    • pp.550-556
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    • 2014
  • Recently, the peptide(or protein)-polymer hybrid materials (PPs) were sought in many research areas as potential building blocks for assembling nanostructures in selective solvents. In PPs, the facile routes of preparing well-defined peptide-polymer bio-conjugates and their specific activities in various applications are important issues. Our strategy to prepare the peptide-polymer hybrid materials was to combine atom transfer radical polymerization (ATRP) method with solid phase peptide synthesis. The standard solid phase peptide synthesis method was employed to prepare the PYGK (proline-tyrosine-glycine-lysine) peptide. PYGK is an analogue peptide, PFGK (proline-phenylalanine-glycine-lysine), which interacted with plasminogen in fibrinolysis. The peptide and the peptide-initiator were characterized with MALDI-TOF mass spectrometry and $^1H$ NMR spectrometer. The peptide-polymer, pSt-PYGK was characterized by GPC, IR, $^1H$ NMR spectrometer and TLC. Spherical micellar aggregates were determined by TEM and SEM. Current synthesis methodology suggested opportunities to create the well-defined peptide-polymer hybrid materials with specific binding activity.

A Review of Geochemical Factors Governing the Phase Transformation of Birnessite (버네사이트 상변화 반응의 지화학적 반응 조절인자 연구)

  • Namgung, Seonyi;Chon, Chul-Min;Lee, Giehyeon
    • Economic and Environmental Geology
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    • v.50 no.6
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    • pp.545-554
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    • 2017
  • Birnessite is one of the dominant Mn (oxyhydr)oxide phases commonly found in soil and deep ocean environments. It typically occurs as nano-sized and poorly crystalline aggregates in the natural environment. It is well known that birnessite participates in a wide variety of bio/geochemical reactions as a reactive mineral phase with structural defects, cation vacancies, and mixed valences of structural Mn. These various bio/geochemical reactions control not only the fate and transport of inorganic and organic substances in the environment, but also the formation of diverse Mn (oxyhydr)oxides through birnessite transformation. This review assessed and discussed about the phase transformation of birnessite under a wide range of environmental conditions and about the potential geochemical factors controlling the corresponding reactions in the literature. Birnessite transformation to other types of Mn (oxyhydr)oxides were affected by dissolved Mn(II), dissolved oxygen, solution pH, and co-existing cation (i.e., $Mg^{2+}$). However, there still have been many issues to be unraveled on the complex bio/geochemical processes involved in the phase transformation of birnessite. Future work on the detail mechanisms of birnessite transformation should be further investigated.

Application of Nano Fe°-impregnated Biochar for the Stabilization of As-contaminated Soil (비소 오염토양의 안정화를 위한 나노 Fe° 담지 바이오차 적용 연구)

  • Choi, Yu-Lim;Angaru, Ganesh Kumar Reddy;Ahn, Hye-Young;Park, Kwang-Jin;Joo, Wan-Ho;Yang, Jae-Kyu;Chang, Yoon-Young
    • Journal of Environmental Impact Assessment
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    • v.29 no.5
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    • pp.350-362
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    • 2020
  • In this study, nano Fe°-impregnated biochar (INPBC) was prepared using pruning residues and one-pot synthetic method and evaluated its performance as an amendment agent for the stabilization of arsenic-contaminated soil. For the preparation of INPBC, the mixture of pruning residue and Fe (III) solution was heated to 220℃ for 3hr in a teflon-sealed autoclave followed by calcination at 600℃ under N2 atmosphere for 1hr. As-prepared INPBC was characterized using FT-IR, XRD, BET, SEM. For the stabilization test of as-prepared INPBC, As-contaminated soils (Soil-E and Soil-S) sampled from agricultural sites located respectively near E-abandoned mine and S-abandoned mine in South Korea were mixed with different of dosage of INPBC and cultivated for 4 weeks. After treatment, TCLP and SPLP tests were conducted to determine the stabilization efficiency of As in soil and showed that the stabilization efficiency was increased with increasing the INPBC dosage and the concentration of As in SPLP extractant of Soil-E was lower than the drinking water standard level of Ministry of Environment of South Korea. The sequential fractionation of As in the stabilized soils indicated that the fractions of As in the 1st and 2nd stages that correspond liable and known as bioavailable fraction were decreased and the fractions of As in 3rd and 4th stages that correspond relatively non-liable fraction were increased. Such a stabilization of As shows that the abundant nano Fe° on the surface of INPBC mixed with As-contaminated soils played the co-precipitation of As leaching from soil by surface complexation with iron. The results of this study may imply that INPBC as a promising amendments for the stabilization of As-contaminated soil play an important role.

Effect of Heating by Nano-Carbon Fiber Infrared Lamps on Growth and Vase Life of Cut Roses and Heating Cost (나노탄소섬유 적외선등 난방이 절화장미의 생육과 수명 및 난방비에 미치는 영향)

  • Lim, Mi-Young;Ko, Chung-Ho;Son, Moon-Sook;Lee, Sang-Bok;Kim, Gil-Ju;Kim, Byung-Soo;Kim, Young-Bok;Jeong, Byoung-Ryong
    • Journal of Bio-Environment Control
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    • v.18 no.1
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    • pp.1-8
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    • 2009
  • The greatest and major cost for cut rose production during winter seasons in Korea is cost of heating the greenhouse. A study was conducted on a cost-efficient heating system to reduce expenses of cut rose growers in times of high energy prices. An infrared heating system utilizing radiant energy has an obvious advantage over other heating methods in that the energy is first used to raise temperatures of plants and other objects and subsequently that of the atmosphere, resulting in faster reaching to desired plant temperatures at a reduced heating cost. In this study the heating effect and heating cost saving of a nano-carbon fiber infrared heating system (NCFIHS) installed in cut rose greenhouses in Gimhae, Gyeongnam Province were analyzed comparatively. In addition growth, quality, and vase life of 'Orange Fresh' roses grown in greenhouses heated by NCFIHS against those grown in greenhouses heated by so called an electrical heating system. In greenhouses with a NCFlHS with a set point air temperature of $20^{\circ}C$, plant temperature was maintained at $1{\sim}2^{\circ}C$ higher than the air temperature, and temperatures of growing bed surface and root zone were maintained at $17{\sim}19^{\circ}C$ throughout cold winter nights. The cost for heating in NCFIHS was about 25 and 51% of that of an electrical heating system and a hot water heating system heated by petroleum, respectively. Growth of roses harvested in greenhouses with a NCFIHS was similar to those grown in greenhouses with an electrical heating system. However, cut roses with more intense petal and leaf colors and a longer vase life (fresh weight and amount of water uptake) were harvested in greenhouses with a NCFIHS as compared to those harvested in greenhouses with an electrical heating system.

Effect of nanosilica and TEOS in hydrophilic coating solution on the surface characteristics of solar cell glass panel (나노실리카와 TEOS가 함유된 친수성 코팅액의 태양광 유리팬널에 미치는 표면 특성 연구)

  • Lee, Soo;Kim, Seung Hye;Hwang, Heon
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.1
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    • pp.152-162
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    • 2017
  • A hydrophilic coating solution was prepared by adding a silane coupling agent and a nano-inorganic oxide in aqueous surfactant solution to increase the efficiency of photovoltaic power generation due to the introduction of antifogging and antifouling properties on the glass surface of the solar cell module. Addition of $Ludox^{(R)}$, a nano-inorganic oxide, to 1% hydrophilic coating solution showed improved hydrophilicity and excellent antifogging effect regardless of $Ludox^{(R)}$ concentration. However, the antifouling effect on the glass surface was showed only when Ludox was added more than 10%. In the case of addition of 0.7% of hydrolyzed TEOS at pH 4, the antifogging effect was maintained as a result of the steam test as well as the antifouling effect even after the coated glass surface was rubbed 100 times with a wet Kimwipe. In addition, from the surface roughness ($R_q$) calculated using AFM data, the higher surface roughness with irregular surface shape was obtained with the higher concentration of TEOS. The addition of 0.7% of TEOS showed relatively high surface roughness and well organized surface condition which can help to improve transmittance of light. In conclusion, $Ludox^{(R)}$ is not required only for the antifogging property. However, at least 10% of Ludox should be added to show antifouling effect and 0.7% of TEOS should be added for good durability.

Analysis for Concentration Range of Fluorescein Sodium (플루오레신나트륨의 농도 범위 분석)

  • Lee, Da-Ae;Kim, Yong-Jae;Yoon, Ki-Cheol;Kim, Kwang-Gi
    • Journal of Biomedical Engineering Research
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    • v.41 no.2
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    • pp.67-74
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    • 2020
  • Brain tumors or gliomas are fatal cancer species with high recurrence rates due to their strong invasiveness. Therefore, the goal of surgery is complete tumor resection. However, the surgery is difficult to distinguish the border because tumors and blood vessels have the same color tone and shape. The fluorescein sodium is used as a fluorescence contrast agent for boundary separation. When the external light source is irradiated, yellow fluorescence is expressed in the tumor, which helps distinguish between blood vessels and tumor boundaries. But, the fluorescence expression of fluorescence sodium depends on the concentration of fluorescein sodium and such analytical data is insufficient. The unclear fluorescence can obscure the boundaries between blood vessels and tumors. In addition, reduce the efficiency of fluorescence sodium use. This paper proposes a protocol of concentration range for fluorescence expression conditions. Fluorescent expression was observed using a near-infrared (NIR) color camera with corresponding dilution using normal saline in 1 ml microtube. The flunoresence emission density range is 1.00 mM to 0.15 mM. The fluorescence emission begin to 1.00 mM and the 0.15 mM discolor. The discolor is difficult to fluorescence emission condition obserbation. Thus, the maximum density range of the bright fluoresecein is 0.15 mM to 0.30 mM. When the concentration range of fluorescein sodium is analyzed based on the gradient of fluorescence expression and the power measurement, the brightest fluorescence is expected to facilitate the complete resection of the tumor. For the concentration range protocol, setting concentration ranges and analyzing fluorescence expression image according to saturation and brightness to find optimal fluorescence concentration are important. Concentration range protocols for fluorescence expression conditions can be used to find optimal concentrations of substances whose expression pattern varies with concentration ranges. This study is expected to be helpful in the boundary classification and resection of brain tumors and glioma.

Conjugated Linoleic Acid Induces Apoptosis by Activating AMPK in MCF-7 Breast Cancer Cells (MCF-7 유방암 세포에서 AMPK 활성에 의한 conjugated linoleic acid의 apoptosis 유도에 관한 연구)

  • Lin, Sun-Kyo;Kim, Hyun-Sook;Park, Ock-Jin;Kim, Young-Min
    • Journal of Life Science
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    • v.18 no.12
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    • pp.1679-1685
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    • 2008
  • Conjugated linoleic acid (CLA) is a naturally occurring compound found in dairy and beef products. It has been shown to suppress cancer cells and to induce apoptosis. Practically, there is emerging evidence that CLA can inhibit chemically induced carcinogenesis in various tissues. However, the molecular mechanisms of CLA on human MCF-7 breast cancer cells have not been clearly explained yet. In this report, we investigated the anti-cancer activity of CLA in MCF-7 cells. It was found that CLA could inhibit the growth of the MCF-7 cells and induce apoptosis, through modulating AMP-activated protein kinase (AMPK) and cyclooxygenase-2 (COX-2). AMPK acts as a cellular fuel gauge and responds to decreased cellular energy status by inhibiting ATP-consuming pathways and increasing ATP-synthesis. CLA treatment with variable concentrations and different time of same-dose CLA on MCF-7 cells resulted in a strong activation of AMPK and an inhibition of COX-2 expression. It supports that CLA induces apoptosis in CLA-treated MCF 7 cells. Therefore, the effects of CLA induced COX-2 expression via activating AMPK can provide new possibility into the understanding the molecular mechanisms of anti-cancer component.

Lamellar-bio nano-hybrid; The Study for Stability of Catechin (Green Tea: EGCG) Using 3-Dimensional Liposome (라멜라-바이오 나노하이브리드: 3 Dimension-liposome을 이용한 카테킨(EGCG)에 안정화에 대한 연구)

  • Hong Geun, Ji;Jung Sik, Choi;Hee Suk, Kwon;Sung Rack, Cho;Byoung Kee, Jo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.2
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    • pp.201-205
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    • 2004
  • In these several years, as many people have been attracted by the functional cosmetics, there are a lot of study to enhance the stability of active ingredients for light, heat, oxygen, etc. in the academic and industrial field. Especially, catechin is well known as strong anti-oxidant, anti-inflammatory and reducing agent for oxidative stress but it is very unstable for light, heat, oxygen. etc. In this study, the stability and skin penetration of catechin are improved by 3-dimensional method. As I-dimension, porous silica is prepared using sol-gel method, and then catechin is adsorbed in pores of silica. As 2-dimension, solid lipid nanoparticles (SLN) are obtained using non-phospholipid vesicles. Finally 3-dimension is completion through lamellar phase self-organization that combines SLN catechin with skin lipid matrix. We used laser light scattering system, cyro-SEM, chromameter, HPLC and image analyzer to analyze our 3-dimentional systems. According to chromameter date, the color stability of 3-dimensional catechin is enhanced by 5-10 times compared with general liposome systems. We also confirmed through HPLC analysis that 3-dimensional catechin is more long lasting. The effect of skin penetration and wrinkle reduction are improved, too.

A Study on Characteristics Analysis of Multichannel Filter Module for Near-infrared Fluorescence Imaging (근적외선 형광 이미징 영상 구현을 위한 다채널 필터 모듈 특성분석 연구)

  • Choi, Jinsoo;Cho, Sang Uk;Kim, Doo-In;Lee, Hak-Guen;Choi, Hak Soo;Jeong, Myung Yung
    • Journal of the Microelectronics and Packaging Society
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    • v.23 no.1
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    • pp.29-34
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    • 2016
  • In this study, development of multichannel filter module and characteristic evaluation for bio imaging were studied. The filter module was fabricated in order to realize near infrared fluorescence imaging of 700 nm and 800 nm wavelength ranges, and contrast imaging analysis for characteristic evaluation of the filter module was studied through signal to back ground ratio (SBR), controlled by parameters such as magnification, exposure, gain. Furthermore, phantoms, which are biomimetic tissue with equal optical properties of kidney and liver, were fabricated to study characteristics of both filter module depending on thickness and exposure amount of light source for bio imaging analysis. The fabricated filter module has more than 4 of SBR difference despite changes of magnification, exposure, gain, and in the case of the kidney phantom and the liver phantom, contrast imaging of more than 4 of SBR was confirmed on 50 mA, 60 mA exposure amount of light source respectively.

The Experimental Study of the Effects of Continuous Traction Therapy in Meridian Sinews Therapy (경근 치료방법 중 지속적 견인요법의 효과에 관한 실험적 연구)

  • Shin, Jeong-Hun;Hwang, Sung-Yeoun;Keum, Kyung-Soo;Kim, Jae-Hyo;Sohn, In-Chul;Ahn, Seong-Hun
    • Korean Journal of Acupuncture
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    • v.29 no.3
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    • pp.385-395
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    • 2012
  • Objectives : Meridian sinew theory was introduced in Miraculous Pivot, Huangdi's Internal Classic, to explain in relation with locations of meridian sinews, causes, mechanisms, and treatment of diseases. The meridian sinews are understood to include muscles, tendons and ligaments, or muscles in the superficial body made up with muscles, ligaments, tendons, fascia etc. This theory shows the similarity or organic relationship between the meridian sinews and muscles. From the Hippocrates(460-385 BC) ages, traction therapy was used as a treatment method on muscular diseases such as low back pain, scoliosis, etc in western medicine. The effects of traction therapy, however, were unclear so that this study was purposed to illustrate the effectiveness of continuous traction therapy and to develop meridian sinews treatment. Methods : We made 2 hypotheses to explain the cause of scoliosis occurrence, muscles contraction and relaxation. As the hypothesis, we made the spinal model having 3 joints with wood and rubber bands. Each of the three joints in the spinal model represents the case of normal(NT; control), contraction(AT 1)and relaxation(AT 2) condition, and distance between the vertebrae joints was measured. Results : Under normal circumstance models, the normal type 1(NT 1; muscle relax state) and normal type 2(NT 2; muscle contract state) all joints were being towed equally. But in an unusual contracted situation, regardless of the relationship of joint area, contracted part of joint was not released. And in a relaxed situation, regardless of joint areas, released parts of joint were further released. These observation results mean that the effects of traction might be different from the purpose of traction therapy of Hippocrates. Conclusions : To explain the effect of traction therapy for scoliosis, the spinal cord model and scoliosis model were made. After vertebral bodies were pulled with different tensile forces, we compared the observed length of the each joints pulled. The results suggested that there were no effects of traction in objected parts with traction method from Hippocrates' design, continuous traction method. Moreover, it may worsen the symptom in worst case. Of course, our results are just the result of experimental models and clinical results may be different. More careful studies, therefore, are required.