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61.
Schmidt Uli; Rudolph Rainer; Bohm Gerald 《Protein engineering, design & selection : PEDS》2001,14(10):769-774
The development of novel delivery systems for therapeutic substancesincludes targeting of the carriers to a specific site or tissuewithin the body of the recipient. This can be accomplished byappropriate receptor-binding domains and requires linking ofthese domains to the carrier. We have used recombinantly expressedpolyomavirus-like particles as a model system and inserted thesequence of a WW domain into different surface loops of theviral capsid protein VP1. In one variant, the WW domain maintainedits highly selective binding properties of proline-rich ligandsand showed an increased affinity but also an accelerated association/dissociationequilibrium compared to the isolated WW domain, thus allowinga short-term coupling of external ligands onto the surface ofthe virus-like particles. 相似文献
62.
63.
The group of conjugated fatty acids known as conjugated linoleic acid (CLA) isomers have been extensively studied with regard to their bioactive potential in treating some of the most prominent human health malignancies. However, CLA isomers are not the only group of potentially bioactive conjugated fatty acids currently undergoing study. In this regard, isomers of conjugated α‐linolenic acid, conjugated nonadecadienoic acid and conjugated eicosapentaenoic acid, to name but a few, have undergone experimental assessment. These studies have indicated many of these conjugated fatty acid isomers commonly possess anti‐carcinogenic, anti‐adipogenic, anti‐inflammatory and immune modulating properties, a number of which will be discussed in this review. The mechanisms through which these bioactivities are mediated have not yet been fully elucidated. However, existing evidence indicates that these fatty acids may play a role in modulating the expression of several oncogenes, cell cycle regulators, and genes associated with energy metabolism. Despite such bioactive potential, interest in these conjugated fatty acids has remained low relative to the CLA isomers. This may be partly attributed to the relatively recent emergence of these fatty acids as bioactives, but also due to a lack of awareness regarding sources from which they can be produced. In this review, we will also highlight the common sources of these conjugated fatty acids, including plants, algae, microbes and chemosynthesis. 相似文献
64.
Dr. Christopher M. Schneider Dr. Wei Li Dr. Kriangsak Khownium Dr. Gerald H. Lushington Prof. Dr. Gunda I. Georg 《ChemMedChem》2016,11(15):1600-1616
Analogues of the anticancer natural product oximidine II were prepared and evaluated for cytotoxicity. One analogue of oximidine II that carries a C15 allylic amide side chain as well as two analogues with C15 vinyl sulfone side chains were found to lack cytotoxicity against the cancer cell line SK‐Mel‐5, thereby confirming the necessity of the C15 enamide side chain of oximidine II for cytotoxicity. Four analogues, designed by comparative molecular similarity index analysis (CoMSIA), that feature a less complex macrolactone scaffold were prepared and tested. The two analogues carrying a C15 vinyl sulfone group and the two analogues with a C15 oximidine II enamide side chain showed weak cytotoxicity against the SK‐Mel‐5 cell line and other cell lines, indicating that the designed simplified macrocycles cannot replace the oximidine II macrocycle. 相似文献
65.
66.
Muthu Kumaran Gnanamani Gary Jacobs Wilson D. Shafer Dennis E. Sparks Shelley Hopps Gerald A. Thomas Burtron H. Davis 《Topics in Catalysis》2014,57(6-9):612-618
Low temperature water–gas shift (LT-WGS) was performed over various group I alkali metal (Li, Na, K, Rb, Cs) promoted cobalt carbide (Co2C) catalysts at temperatures ranging from 453 to 573 K and atmospheric pressure. Cobalt carbide (Co2C) was found to be active for the WGS reaction. The stability of the catalyst is related to the stability of the cobalt carbide phases under reaction conditions. Potassium promoted cobalt carbide catalysts exhibited higher activity and stability compared to the other alkali promoted catalysts for LT-WGS. X-ray diffraction analyses of fresh and used catalysts suggest that the origin of deactivation of the catalysts is primarily due to the chemical transition of cobalt from carbide to metal during WGS. 相似文献
67.
Evaluation of the degree of cure of a coating 总被引:1,自引:0,他引:1
Coating cure is compared using pencil hardness, MEK rubs, and thumb twist test to evaporation rate analysis (ERA). ERA is rated most objective and reproducible. Department of Polymer Science, Hattiesburg, MS. Rockville, MD. 相似文献
68.
Dr. Carolyn Vargas Prof. Dr. Gerald Radziwill Dr. Gerd Krause Dr. Anne Diehl Prof. Dr. Sandro Keller Dr. Nestor Kamdem Prof. Dr. Constantin Czekelius Annika Kreuchwig Dr. Peter Schmieder Dr. Declan Doyle Prof. Dr. Karin Moelling Dr. Volker Hagen Dr. Markus Schade Prof. Dr. Hartmut Oschkinat 《ChemMedChem》2014,9(7):1458-1462
PDZ (PSD‐95, Dlg, ZO‐1) domains are ubiquitous interaction modules that are involved in many cellular signal transduction pathways. Interference with PDZ‐mediated protein–protein interactions has important implications in disease‐related signaling processes. For this reason, PDZ domains have gained attention as potential targets for inhibitor design and, in the long run, drug development. Herein we report the development of small molecules to probe the function of the PDZ domain from human AF6 (ALL1‐fused gene from chromosome 6), which is an essential component of cell–cell junctions. These compounds bind to AF6 PDZ with substantially higher affinity than the peptide (Ile‐Gln‐Ser‐Val‐Glu‐Val) derived from its natural ligand, EphB2. In intact cells, the compounds inhibit the AF6–Bcr interaction and interfere with epidermal growth factor (EGF)‐dependent signaling. 相似文献
69.
Sahas R. Rathi E. Bryan Coughlin Shaw Ling Hsu Charles S. Golub Gerald H. Ling Michael J. Tzivanis 《Polymer》2012,53(14):3008-3016
A method to overcome the brittleness of poly (l-lactic acid) (PLLA) by kinetically trapping a continuous low Tg amorphous phase is presented. This morphology is accomplished by exploiting the significant difference in the crystallization temperatures of PLLA vs its stereocomplex with the poly (d-lactic acid) (PDLA) isomer. In our studies, the D isomer is the end block of a triblock copolymer with a configuration of the form PDLAn–Soft Blockm–PDLAn. As demonstrated in this study, when blended with PLLA, the obtained morphology, and improvement in the sample toughness and flexibility, strongly depend on the miscibility of the midblock in the triblock copolymer with the matrix PLLA. The difference in the chemical nature of the midblock clearly affected the stereocomplex crystallization between the PDLA end blocks, the PLLA matrix polymer, and the morphology formed. It is found that the miscible midblock gives rise to a soft continuous amorphous phase while in the case of an immiscible midblock, a glassy phase separated amorphous phase is formed. Dramatically different physical properties can be obtained for various PLLA/triblock copolymer blends giving access to tough, yet flexible, semicrystalline PLLA blends. 相似文献
70.
Thomas Vogl Gregor Mori Wolfgang Havlik Gerald Zehethofer 《BHM Berg- und Hüttenm?nnische Monatshefte》2012,157(8-9):323-331
CO2 corrosion of carbon steel is a serious problem in oil and gas production, since the most used materials are low alloyed carbon steels. There are many approaches to handle the problem of CO2 corrosion. One flexible and economic way to control corrosion in oil and gas facilities is inhibition but the efficiency of an inhibitor is often limited by flow velocities. To investigate inhibitor efficiency in a superficial flow with high gas velocities neither standardized test had been available nor publications about that topic. Therefore the goal was to do the first investigations in that important field. To reach this aim a special, not standardized flow loop test system has been constructed. Results of these investigations have shown that differences in inhibitor efficiencies are related to chemical composition and flow velocities. 相似文献