The Experts below are selected from a list of 204 Experts worldwide ranked by ideXlab platform
Philip G. De Groot - One of the best experts on this subject based on the ideXlab platform.
-
Glycated Proteins Modulate Tissue–Plasminogen Activator-Catalyzed Plasminogen Activation
Biochemical and biophysical research communications, 1997Co-Authors: Inge W.g. Bobbink, W. L. H. Tekelenburg, Jan J. Sixma, Hetty C. De Boer, J. D. Banga, Philip G. De GrootAbstract:Abstract Plasminogen activation by tissue–plasminogen activator (t-PA) is accelerated by the presence of a macromolecular surface, which acts as a Template that brings enzyme and substrate in close proximity. Modification of lysine residues, which are important for this Template Function, occurs in diabetic patients as a consequence of glycation of proteins. In this study, we investigated the effects of glycation of fibrin and other proteins in t-PA-catalyzed plasmin formation. Plasminogen activation on glycated fibrin(ogen) was increased compared to non-glycated fibrin(ogen), which could fully be attributed to an increased affinity of t-PA for glycated fibrin(ogen). Binding of plasminogen to glycated fibrin was increased, but did not contribute to increased plasminogen activation. Both plasminogen activator inhibitor-1 (PAI-1) binding and activity were increased on glycated fibrin. Induction of Template Function in plasminogen activation was also observed on immobilized glycated bovine serum albumin (BSA) and human γ-globulins (IgG). Increased plasmin generation at sites of deposition of glycated proteins may lead to increased extracellular matrix breakdown and thereby affect the integrity of the endothelial monolayer. Moreover, soluble glycated BSA and glycated IgG can inhibit t-PA binding to immobilized glycated fibrin and interfere with fibrinolysis in diabetic patients.
Thomas Greber - One of the best experts on this subject based on the ideXlab platform.
-
graphene and boron nitride single layers
arXiv: Materials Science, 2010Co-Authors: Klaus D Sattler, Thomas GreberAbstract:This Chapter deals with single layers of carbon (graphene) and hexagonal boron nitride on transition metal surfaces. The transition metal substrates take the role of the support and allow due to their catalytic activity the growth of perfect layers by means of chemical vapor deposition. The layers are sp2 hybridized honeycomb networks with strong in plane sigma and weaker pi bonds to the substrate and to the adsorbates. This hierarchy in bond strength causes anisotropic elastic properties, where the sp2 layers are stiff in plane and soft out of plane. A corrugation of these layers imposes a third hierarchy level in bond energies, with lateral bonding to molecular objects with sizes between 1 and 5 nanometer. This extra bond energies are in the range of thermal energies kT at room temperature and are particularly interesting for nanotechnology. The concomitant Template Function will be discussed. The peculiar bond hierarchy also imposes intercalation as another property of sp2 layer systems. Last but not least sp2 layer systems are particularly robust, i.e. survive immersion into liquids, which is a promise for sp2 layers being useful outside ultra high vacuum. The Chapter shortly recalls the synthesis, describes the atomic and electronic structure, is followed by a discussion of properties like intercalation and the use of sp2 layers on metals as tunneling junctions or as Templates. The Chapter ends with an Appendix that summarizes the basics of atomic and electronic structure of honeycomb lattices. Of course the Chapter does not cover all aspects of sp2 single layers. Topics like free standing layers, edge structures of ribbons, topological defects, or mechanical and chemical properties were not covered.
-
Comparison of electronic structure and Template Function of single-layer graphene and a hexagonal boron nitride nanomesh on Ru(0001)
Physical Review B, 2009Co-Authors: Thomas Brugger, Sebastian Günther, Bin Wang, J. Hugo Dil, Marie-laure Bocquet, Jürg Osterwalder, Joost Wintterlin, Thomas GreberAbstract:The structure of a single-layer graphene on Ru(0001) is compared with that of a single-layer hexagonal boron nitride nanomesh on Ru(0001). Both are corrugated $s{p}^{2}$ hybridized networks and display a $\ensuremath{\pi}$ band gap at the $\overline{\text{K}}$ point of their $1\ifmmode\times\else\texttimes\fi{}1$ Brillouin zone. In contrast to $h\text{-BN}/\text{Ru}(0001)$, $g/\text{Ru}(0001)$ has a distinct Fermi surface. Together with the band structure measurements this indicates that $0.1e$ per $1\ifmmode\times\else\texttimes\fi{}1$ unit cell are transferred from the Ru substrate to the graphene. Photoemission from adsorbed xenon on $g/\text{Ru}(0001)$ identifies two $\text{Xe}\text{ }5{p}_{1/2}$ lines, separated by 240 meV, which reveals a corrugated electrostatic potential energy surface like on $h\text{-BN}/\text{Rh}(111)$. These two Xe species are related to the topography of the Template and have different desorption energies.
Mengbiao Yuan - One of the best experts on this subject based on the ideXlab platform.
-
Inhibition of telomerase activity by HDV ribozyme in cancers.
Journal of experimental & clinical cancer research : CR, 2011Co-Authors: Dachuan Jin, Yanjing Gao, Mengbiao YuanAbstract:Background Telomerase plays an important role in cell proliferation and carcinogenesis and is believed to be a good target for anti-cancer drugs. Elimination of Template Function of telomerase RNA may repress the telomerase activity.
Anjiang Cai - One of the best experts on this subject based on the ideXlab platform.
-
a facile synthesis of luminescent yvo4 eu3 hollow microspheres in virtue of Template Function of the sds peg soft clusters
Solid State Sciences, 2012Co-Authors: Juan Wang, Yinglin Yan, Mirabbos Hojamberdiev, Xiaoguang Ruan, Anjiang CaiAbstract:Hollow europium-doped yttrium orthovanadate (YVO4:Eu3+) microspheres were fabricated via a sodium dodecyl sulfate (SDS)–polyethylene glycol (PEG)-assisted hydrothermal technique. The as-synthesized hollow YVO4:Eu3+ microspheres were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence spectroscopy (PL). The obtained results showed that the morphology and size of the hollow microspheres have a strong dependence on the hydrothermal reaction time of the YVO4:Eu3+ powders. It is believed that the SDS–PEG clusters perform a Function of dual soft-Template that results in a unique Template-induced secondary assembly in the one-pot synthesis of hollow YVO4:Eu3+ microspheres. The photoluminescence measurement revealed that the YVO4:Eu3+ powders with a spherical hollow shape have better red luminescence compared to the YVO4:Eu3+ solid microspheres. As a result, the controlled synthesis of hollow YVO4:Eu3+ microspheres not only has a great theoretical significance in studying the three-dimensional control and selective synthesis of inorganic materials but also benefits the potential applications based on hollow YVO4:Eu3+ microspheres owing to reducing the usage of expensive rare-earth elements.
-
A facile synthesis of luminescent YVO4:Eu3+ hollow microspheres in virtue of Template Function of the SDS–PEG soft clusters
Solid State Sciences, 2012Co-Authors: Juan Wang, Yinglin Yan, Mirabbos Hojamberdiev, Xiaoguang Ruan, Anjiang CaiAbstract:Hollow europium-doped yttrium orthovanadate (YVO4:Eu3+) microspheres were fabricated via a sodium dodecyl sulfate (SDS)–polyethylene glycol (PEG)-assisted hydrothermal technique. The as-synthesized hollow YVO4:Eu3+ microspheres were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence spectroscopy (PL). The obtained results showed that the morphology and size of the hollow microspheres have a strong dependence on the hydrothermal reaction time of the YVO4:Eu3+ powders. It is believed that the SDS–PEG clusters perform a Function of dual soft-Template that results in a unique Template-induced secondary assembly in the one-pot synthesis of hollow YVO4:Eu3+ microspheres. The photoluminescence measurement revealed that the YVO4:Eu3+ powders with a spherical hollow shape have better red luminescence compared to the YVO4:Eu3+ solid microspheres. As a result, the controlled synthesis of hollow YVO4:Eu3+ microspheres not only has a great theoretical significance in studying the three-dimensional control and selective synthesis of inorganic materials but also benefits the potential applications based on hollow YVO4:Eu3+ microspheres owing to reducing the usage of expensive rare-earth elements.
José Antonio Odriozola - One of the best experts on this subject based on the ideXlab platform.
-
Understanding the role of the cosolvent in the zeolite Template Function of imidazolium-based ionic liquid.
The journal of physical chemistry. B, 2014Co-Authors: Regla Ayala, Svetlana Ivanova, José María Martínez Blanes, Francisca Romero-sarria, José Antonio OdriozolaAbstract:In this work, a study for understanding the role played by [ClBmim], [BF4Bmim], [PF6Bmim], and [CH3SO3Bmim] ionic liquids (ILs) in the synthesis of zeolites is presented. The use of [ClBmim] and [CH3SO3Bmim] ILs, as reported earlier [ Chem. Eur. J. 2013 , 19 , 2122 ] led to the formation of MFI or BEA type zeolites. Contrary, [BF4Bmim] and [PF6Bmim] ILs did not succeed in organizing the Si-Al network into a zeolite structure. To try to explain these results, a series of quantum mechanical calculations considering monomers ([XBmim]) and dimers ([XBmim]2) by themselves and plus cosolvent (water or ethanol) were carried out, where X ≡ Cl(-), BF4(-), PF6(-), or CH3SO3(-). Our attention was focused on the similarities and differences among the two types of cosolvents and the relation between the structure and the multiple factors defining the interactions among the ILs and the cosolvent. Although a specific pattern based on local structures explaining the different behavior of these ILs as a zeolite structuring Template was not found, the calculated interaction energies involving the Cl(-) and CH3SO3(-) anions were very close and larger than those for BF4(-) and PF6(-) species. These differences in energy can be used as an argument to describe their different behavior as structure directing agents. Moreover, the topology of the cosolvent is also an ingredient to take into account for a proper understanding of the results.
