• Title/Summary/Keyword: Cell complex

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Variations of leaf thickness in the Chrysanthemum zawadskii complex and in two related Korean species: C. boreale and C. indicum (Asteraceae) (국화속 구절초무리와 근연종인 산국 및 감국 에서 보이는 잎의 해부학적 특징)

  • Kim, Jung Sung;Tobe, Hiroshi
    • Korean Journal of Plant Taxonomy
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    • v.39 no.1
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    • pp.29-34
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    • 2009
  • The Chrysanthemum zawadskii complex is demarcated from other species by having the white and pink ligulate flowers. Its morphological characters are greatly diversified, so that various classification systems have been suggested. The character of leaf thickness has been mentioned as the characteristic for recognizing some of infra-specific taxa within this complex. In this study, we used longitudinal leaf sections to investigate the leaf thickness and cell number of leaf blades of 13 populations including those of the members of the C. zawadskii complex, as well as 4 populations of the related species of C. boreale and C. indicum. From the result, it was clear that the leaves were thicker in populations of C. boreale, C. indicum and C. zawadskii complex (diminishing in that order), and that the leaves were composed of about 9 cell layers in all populations. Within the C. zawadskii complex, leaf shape and thickness varied among the populations. It was very interesting that the taxa with restricted distribution, like C. zawadskii var. tenuisectum, C. zawadskii var. alpinum, C. zawadskii var. lucidum, and C. zawadskii subsp. coreanum had a thicker leaves than found among widely occurring taxa. From this, leaf thickness is supposed to be an adaptation to the unique habitat of each population.

The Pleiotropy of Telomerase against Cell Death

  • Sung, Young Hoon;Choi, Yoon Sik;Cheong, Cheolho;Lee, Han-Woong
    • Molecules and Cells
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    • v.19 no.3
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    • pp.303-309
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    • 2005
  • The end of eukaryotic genomic DNA is capped by a specialized structure called as "telomere" which consists of the repetitive array of nucleotide sequence, TTAGGG, in humans and mice, and a variety of binding proteins. Telomerase is a ribonucleoprotein (RNP) complex responsible for the elongation of telomeres to maintain the genomic integrity, and is composed of telomerase reverse transcriptase (TERT), telomerase RNA component (TERC), and their associated factors regulating the catalytic activity of telomerase. Although it is now apparent that telomerase protects cells from apoptosis via the maintenance of genomic integrity by stabilizing telomeres, our understanding for the physiological role of telomerase is yet far from completion, and emerging evidence suggests that telomerase has additional extratelomeric roles in mediating cell survival and anti-apoptotic functions against various cytotoxic stresses. Here we summarize and discuss how telomerase and telomeres are involved in mediating cellular protection against apoptosis.

Preparation and Characteristics of $\gamma-LiAlO_2$ Fibers by the Sol-Gel Method (졸-겔 법에 의한 $\gamma-LiAlO_2$ 화이버의 제조 및 특성)

  • 현상훈;홍성안;신현철
    • Journal of the Korean Ceramic Society
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    • v.32 no.2
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    • pp.197-208
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    • 1995
  • ${\gamma}$-LiAlO2 fibers for fiber reinforced molten carbonate fuel cell (MCFC) matrix have been produced from LiAlO2 complex polymeric sols using the sol-gel process. The stable and spinnable LiAlO2 sols could be synthesized by mixing LiNO3 alcohol solutions in aluminum complex polymeric sols prepared through the condensationpolymerization reaction of 1 more of aluminum tri-sec-butoxide with 0.55 mole of mixed chelates (mole ratio of acetylaceton/triethanolamine=0.25/0.3). It was found that the viscosity range for fiber-spinning should be higher than 30 poise. The defect-free flexible ${\gamma}$-LiAlO2 fibers with the average tensile strength of 350 MPa could be obtained when the spinned fibers were heat-treated to 120$0^{\circ}C$ on the specified heating schedule after dried at room temperature.

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A Study on the Synthesis of [RCOOH]-$\varepsilon$-Caprolactam-Montmorillonite Intercalations-complex and its Isothermal Decomposition in High Vacuum ([RCOOH]-$\varepsilon$-Caprolactam-Montmorillonite 층간화합물의 합성과 고진공상태하에서의 등온 분해에 관한 연구)

  • 조성준
    • Journal of the Korean Ceramic Society
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    • v.33 no.8
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    • pp.909-914
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    • 1996
  • In this research [RCOOH]-$\varepsilon$-Caprolactam-Montmorillonite was synthesized by reaction between Na-Mont-morillonite (10-Carboxy-n-decyl)dimethylethylammonium (=RCCOH) ion and $\varepsilon$-Caprolactame-Motmorillonite ob-tained was 3.62$\AA$ After heat treatment of this intercalations complex at 37$^{\circ}C$ in high vacuum for 12 h 24 h, 40 h and 90 h the basal spacing was reduced to 35.8$\AA$, 34.2, 17.5 $\AA$ and 16.6$\AA$ respectively. The calculated amount of free $\varepsilon$-caprolactame included int he intercaltions complex and that of $\varepsilon$-caprolactame which is interca-lated into the interlayer space of montomorillonite and still remained after heat treatment are 4.6~4.9 and 0.5 molecules per unite cell of montmorillonite respectively.

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An Experimental Study on the Effect of Electric Field the Ornithine Decarboxylase Activity Change of Myeloid Cells According to Ionizing Radiation Exposure (이온화방사선 피폭에 의한 골수세포의 Ornithine Decarboxylase 활성도의 변화에 대한 전계장의 영향에 관한 실험적 연구)

  • 정문호
    • Journal of Environmental Health Sciences
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    • v.21 no.1
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    • pp.78-85
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    • 1995
  • Ornithine decarboxylase(ODC) is an indicate enzyme in carcinogenesis. We divided Sprague Dawley rats into six groups: control, electric field exposure, X-ray only irradiation, X-ray irradiation with electric field exposure group, Sr-90 injected group and Sr-90 and electric field complex exposure group. The ODC activity was measured in rat's bone marrow cell every week. The results were summarized as follows: The ODC activitied was increased in X-ray irradiated, Sr-90 injected and Sr-90 and electric field complex exposed group as compared with that of control(p<0.05). The ODC activity was increased comparing that of control neither in X-ray and electric field complex exposed group nor electric field only exposed group. This result suggests that the electric field doesn't have myeloid carcinogenicity and myeloid cancer incidence caused by ionized radiation is suppressed by electric field exposure.

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Development of A Three-Dimensional Thermo-Hydraulic Computer Code for Incompressible Flows in Complex Geometries

  • Park, Seok-Ki;Lee, Yong-Bum;Hwang, Jong-Sun;Nam, Ho-Yun;Mann Cho
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05b
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    • pp.173-178
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    • 1996
  • A three-dimensional thermo-hydraulic computer code is developed for simulation of incompressible flows in complex geometries. The computer code employs a body-fitted, nonorthogonal grid system in order to efficiently handle the complex geometries encountered in many engineering applications. The finite volume method is used to discretize the governing equations and the convection term is treated by higher-order bounded schemes. The cell-centered, nonstaggered grid arrangement is adopted and the resulting checkerboard pressure oscillation is avoided by use of momentum interpolation practice. The computer code employs the SIMPLE algorithm for pressure and velocity coupling and the k-$\varepsilon$ turbulence for turbulent calculation. The computer code has been tested through application to a variety of test problems and some results are presented in this paper

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Propamidine decreas mitochondrial complex III activity of Botrytis cinerea

  • Wu, Fangli;Jin, Weibo;Feng, Juntao;Chen, Anliang;Ma, Zhiqing;Zhang, Xing
    • BMB Reports
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    • v.43 no.9
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    • pp.614-621
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    • 2010
  • Propamidine, an aromatic diamidine compound, is widely used as an antimicrobial agent. To uncover its mechanism on pathogenetic fungi, Botrytis cinerea as an object was used to investigate effects of propamidine in this paper. The transmission electron microscope results showed that the mitochondrial membranes were collapsed after propamidine treatment, followed that mitochondria were disrupted. Inhibition of whole-cell and mitochondrial respiration by propamidine suggested that Propamidine is most likely an inhibitor of electron transport within Botrytis cinerea mitochondria. Furthermore, the mitochondrial complex III activity were inhibited by propamidine.

The fabrication of europium complex electroluminescence using BCP as hole blocking layer

  • Liang, Yujun;Zhang, Hongjie;Kim, Beung-Kwon;Jung, Young-Ho;Park, Jo-Yong;Myung, Kwang-Shik;Khatkar, S.P.;Han, Sang-Do
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.578-580
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    • 2002
  • A bright and highly monochromatic red organic electroluminescent device based on a poly(N-vinylcarbazole) host was made. The device structure consists of poly(N-vinylcarbazole) dispersed with a europium complex as an emitting layer and a hole blocking layer of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP). The EL cell exhibited just characteristic emission of europium ion.

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Review on Studies of Wild Ginseng Complex Pharmacopuncture Related to Obesity Treatment (비만치료와 관련된 산삼복합약침요법에 대한 연구 동향 고찰)

  • Park, Jung-Sik
    • Journal of Korean Medicine for Obesity Research
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    • v.21 no.1
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    • pp.42-48
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    • 2021
  • Objectives: The purpose of this study was to review the studies of the wild ginseng complex pharmacopuncture related to obesity treatment. Methods: We searched the papers with key words of 'wild ginseng complex pharmacopuncture', 'wild ginseng pharmacopuncture', 'obesity', 'fat', 'weight' in Oriental medicine Advanced Searching Integrated System, KRpia, Koreanstudies Information Service System, Research Information Sharing Service, KoreaMed and PubMed, Scopus. We classified the papers by year, content and study type. Results: There were 7 studies about the wild ginseng pharmacopuncture related to obesity treatment. Cell studies were excluded because they were not related to obesity. Analysis of 3 animal experiments and 4 clinical studies were conducted to describe each research subject, method, and research results. Conclusion: More interest and further research will be needed on wild ginseng pharmacopuncture related to obesity treatment in the Korean medicine to achieve clinical application and to develop treatment protocols for the obesity disease.

A New Model for the Reduced Form of Purple Acid Phosphatase: Structure and Properties of $[Fe_2BPLMP(OAc)_2](BPh_4)_2$

  • 임선화;이진호;이강봉;강성주;허남휘;Jang, Ho G.
    • Bulletin of the Korean Chemical Society
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    • v.19 no.6
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    • pp.654-660
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    • 1998
  • $[Fe^{II}Fe^{III}BPLMP(OAc)_2](BPh_4)_2$ (1), a new model for the reduced form of the purple acid phosphatases, has been synthesized by using a dinucleating ligand, 2,6-bis[((2-pyridylmethyl)(6-methyl-2-pyridylmethyl)amino) methyl]-4-methylphenol (HBPLMP). Complex I has been characterized by X-ray diffraction method as having (μ-phenoxo)bis(acetato)diiron core. Complex 1 was crystallized in the monoclinic space group C2/c with the following cell parameters: a=41.620(6) Å, b=14.020(3) Å, c=27.007(4) Å, β=90.60(2)°, and Z=8. The iron centers in the complex 1 are ordered as indicated by the difference in the Fe-O bond lengths which match well with typical $Fe^{III}-O\; and\; Fe^{II}-O$ bond lengths. Complex 1 has been studied by electronic spectral, NMR, EPR, SQUID, and electochemical methods. Complex 1 exhibits strong bands at 592 nm, 1380 nm in $CH_3CN$ (ε = 1.0 × 103 , 3.0 × 102). These are assigned to $phenolate-to-Fe^{III}$ and intervalence charge-transfer transitions, respectively. Its NMR spectrum exhibits sharp isotropically shifted resonances, which number half of those expected for a valence-trapped species, indicating that electron transfer between $Fe^{II}\;and\;Fe^{III}$ centers is faster than NMR time scale. This complex undergoes quasireversible one-electron redox processes. The $Fe^{III}_2/Fe^{II}Fe^{III}\;and\;Fe^{II}Fe^{III}/Fe^{II}_2$ redox couples are at 0.655 and -0.085 V vs SCE, respectively. It has $K_{comp}=3.3{\times}10^{12}$ representing that BPLMP/bis(acetate) ligand combination stabilizes a mixed-valence $Fe^{II}Fe^{III}$ complex in the air. Complex 1 exhibits a broad EPR signal centered near g=1.55 which is a characteristic feature of the antiferromagnetically coupled high-spin $Fe^{II}Fe^{III}$ system $(S_{total}=1/2)$. This is consistent with the magnetic susceptibility study showing the weak antiferromagnetic coupling $(J= - 4.6\;cm^{-1},\; H= - 2JS_1{\cdot}S2)$ between $Fe^{II}\; and \;Fe^{III}$center.