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131.
Nicole Schreiber Notburga Gierlinger Norbert Pütz Peter Fratzl Christoph Neinhuis Ingo Burgert 《The Plant journal : for cell and molecular biology》2010,61(5):854-861
Root contraction has been described for many species within the plant kingdom for over a century, and many suggestions have been made for mechanisms behind these contractions. To move the foliage buds deeper into the soil, the proximal part of the storage root of Trifolium pratense contracts by up to 30%. Anatomical studies have shown undeformed fibres next to strongly deformed tissues. Raman imaging revealed that these fibres are chemically and structurally very similar to poplar (Populus) tension wood fibres, which are known to generate high tensile stresses and bend leaning stems or branches upright. Analogously, an almost pure cellulosic layer is laid down in the lumen of certain root fibres, on a thin lignified secondary cell wall layer. To reveal its stress generation capacities, the thick cellulosic layer, reminiscent of a gelatinous layer (G‐layer) in tension wood, was selectively removed by enzymatic treatment. A substantial change in the dimensions of the isolated wood fibre bundles was observed. This high stress relaxation indicates the presence of high tensile stress for root contraction. These findings indicate a mechanism of root contraction in T. pratense (red clover) actuated via tension wood fibres, which follows the same principle known for poplar tension wood. 相似文献
132.
Romy F.J. Janser Ranjith K. Meka Zack E. Bryant Enoch A. Adogla Elizabeth K. Vogel Jaimie L. Wharton Cynthia M. Tilley Catherine N. Kaminski Seth L. Ferrey Severine Van slambrouck Wim F.A. Steelant Ingo Janser 《Bioorganic & medicinal chemistry letters》2010,20(6):1848-1850
A series of ethacrynic acid analogues, lacking the α,β-unsaturated carbonyl unit, was synthesized and subsequently evaluated for their ability to inhibit the migration of human breast cancer cells, MCF-7/AZ. Several of the analogues were already active in the low micromolar range, whereas ethacrynic acid itself shows no potential to inhibit the migration of these cancer cells. Preliminary studies show that the presence of one or more methoxy groups at the phenyl ring of ethacrynic acid is important in order for the ethacrynic acid analogues to demonstrate an inhibitory effect on the migration. 相似文献
133.
Jennifer A. Kowalski Alan D. Swinamer Ingo Muegge Anne B. Eldrup Alison Kukulka Charles L. Cywin Stéphane De Lombaert 《Bioorganic & medicinal chemistry letters》2010,20(12):3703-3707
A 270-membered library of trisubstituted ureas was synthesized and evaluated for inhibition of soluble epoxide hydrolase. Library design and reagent selection was guided by the use of a pharmacophore model and synthesis of the array was enabled with a general solid-phase method. This array approach facilitated multi-dimensional SAR around this series and identified functionality responsible for binding affinity, as well as opportunities for modulating the overall in vitro profiles of this class of soluble epoxide hydrolase inhibitors. 相似文献
134.
Stenting of the Shelhigh pulmonary conduit was performed 2 years after a Ross procedure because of a stenosis of the distal segment. We used the new Siemens Artis Zeego technology. A precise placement of the stent to release the stenosis within the distal segment simultaneously retaining a competent valve was possible by using the Dyna-computed tomography technology. The early onset of a stenosis of the Shelhigh xenograft in the pulmonary position is alarming, thus, its use can not be recommended for a replacement of the pulmonary valve. 相似文献
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Gralle M Schäfer I Seibel P Pääbo S 《Biochemical and biophysical research communications》2010,402(4):747-749
Targeting of nuclear-encoded proteins to different organelles, such as mitochondria, is a process that can result in the redeployment of proteins to new intracellular destinations during evolution. With the sequencing of the Neandertal genome, it has become possible to identify amino acid substitutions that occurred on the modern human lineage since its separation from the Neandertal lineage. Here we analyze the function of two substitutions in mitochondrial targeting sequences that occurred and rose to high frequency recently during recent human evolution. The ancestral and modern versions of the two targeting sequences do not differ in the efficiency with which they direct a protein to the mitochondria, an observation compatible with the neutral theory of molecular evolution. 相似文献
137.
Qingchun Zhou Ingo Braasch Alexander Froschauer Astrid Boehne Christina Schultheis Manfred Schartl Jean-Nicolas Volff 《遗传学报》2010,37(3):181-188
A consensus sequence,encoding a putative DNA polymerase type B derived from a Polinton transposon,was assembled from the sex determination region of Xiphophorus maculatus.This predicted protein,which is 1,158 as in length,contains a DNA_pol_B_2 domain and a DTDS motif.The DNA polymerase type B gene has about 10 copies in the haploid X.maculatus genome with one Y-specific copy.Interestingly,it has specific copies on the W chromosome in the X.maculatus Usumacinta strain (sex determination with female heterogamety),which represent new markers for this type of sex chromosome in platyfish.This marker with W-and Y-specific copies suggests relationship between different types of gonosomes and allows comparing male and female heterogameties in the platyfish.Further molecular analysis of the DNA polymerase type B gene in X.maculatus will shed new light on the evolution of sex chromosomes in platyfish. 相似文献
138.
Luminescent magnetic particles (LuMaPs) are attractive tools for life science applications such as multimodal imaging, analyte monitoring, nanotherapeutics, and combinations thereof. LuMaPs consist of at least one magnetic and one luminescent component which often are incorporated in a (polymeric) matrix. Alarge variety of materials do exist for the components that make up LuMaPs. However, a smart selection and combination is required for achieving useful tools. While the magnetic component mainly influences the response to a magnetic field, the luminophore can act as label, sensor, or therapeutic agent. The matrix fulfills tasks such as stabilizing the luminophore and magnet, carrying useful functional groups on its surface, or hosting smart drug delivery systems. Surface modifications with targeting ligands can further improve the applicability of LuMaPs, for example in biomedicine. This review provides an overview on LuMaPs with respect to the materials used and to its structures. Routes toward LuMaPs are outlined, and potential applications are discussed. 相似文献
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