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211.
212.
Cell adhesion to extracellular matrix (ECM) components through cell-surface integrin receptors is essential to the formation, maintenance and repair of numerous tissues, and therefore represents a central theme in the design of bioactive materials that successfully interface with the body. While the adhesive responses associated with a single ligand have been extensively analyzed, the effects of multiple integrin subtypes binding to multivalent ECM signals remain poorly understood. In the present study, we generated a high throughput platform of non-adhesive surfaces presenting well-defined, independent densities of two integrin-specific engineered ligands for the type I collagen (COL-I) receptor alpha(2)beta(1) and the fibronectin (FN) receptor alpha(5)beta(1) to evaluate the effects of integrin cross-talk on adhesive responses. Engineered surfaces displayed ligand density-dependent adhesive effects, and mixed ligand surfaces significantly enhanced cell adhesion strength and focal adhesion assembly compared to single FN and COL-I ligand surfaces. Moreover, surfaces presenting mixed COL-I/FN ligands synergistically enhanced FAK activation compared to the single ligand substrates. The enhanced adhesive activities of the mixed ligand surfaces also promoted elevated proliferation rates. Our results demonstrate interplay between multivalent ECM ligands in adhesive responses and downstream cellular signaling. 相似文献
213.
Background
The leukocyte common antigen related receptor (LAR) protein has been shown to modulate the signal transduction of a number of different growth factors, including insulin and insulin-like growth factor 1. Splice variants exhibit differing roles and are expressed according to tissue type and developmental stage. 相似文献214.
Esther Heikens Masja Leendertse Lucas M Wijnands Miranda van Luit-Asbroek Marc JM Bonten Tom van der Poll Rob JL Willems 《BMC microbiology》2009,9(1):19-7
Background
Enterococcus faecium has globally emerged as a cause of hospital-acquired infections with high colonization rates in hospitalized patients. The enterococcal surface protein Esp, identified as a potential virulence factor, is specifically linked to nosocomial clonal lineages that are genetically distinct from indigenous E. faecium strains. To investigate whether Esp facilitates bacterial adherence and intestinal colonization of E. faecium, we used human colorectal adenocarcinoma cells (Caco-2 cells) and an experimental colonization model in mice. 相似文献215.
Hetty C van den Broeck Teun WJM van Herpen Cees Schuit Elma MJ Salentijn Liesbeth Dekking Dirk Bosch Rob J Hamer Marinus JM Smulders Ludovicus JWJ Gilissen Ingrid M van der Meer 《BMC plant biology》2009,9(1):41
Background
Gluten proteins can induce celiac disease (CD) in genetically susceptible individuals. In CD patients gluten-derived peptides are presented to the immune system, which leads to a CD4+ T-cell mediated immune response and inflammation of the small intestine. However, not all gluten proteins contain T-cell stimulatory epitopes. Gluten proteins are encoded by multigene loci present on chromosomes 1 and 6 of the three different genomes of hexaploid bread wheat (Triticum aestivum) (AABBDD). 相似文献216.
Roberts SC Gosling LM Carter V Petrie M 《Proceedings. Biological sciences / The Royal Society》2008,275(1652):2715-2722
Previous studies in animals and humans show that genes in the major histocompatibility complex (MHC) influence individual odours and that females often prefer odour of MHC-dissimilar males, perhaps to increase offspring heterozygosity or reduce inbreeding. Women using oral hormonal contraceptives have been reported to have the opposite preference, raising the possibility that oral contraceptives alter female preference towards MHC similarity, with possible fertility costs. Here we test directly whether contraceptive pill use alters odour preferences using a longitudinal design in which women were tested before and after initiating pill use; a control group of non-users were tested with a comparable interval between test sessions. In contrast to some previous studies, there was no significant difference in ratings between odours of MHC-dissimilar and MHC-similar men among women during the follicular cycle phase. However, single women preferred odours of MHC-similar men, while women in relationships preferred odours of MHC-dissimilar men, a result consistent with studies in other species, suggesting that paired females may seek to improve offspring quality through extra-pair partnerships. Across tests, we found a significant preference shift towards MHC similarity associated with pill use, which was not evident in the control group. If odour plays a role in human mate choice, our results suggest that contraceptive pill use could disrupt disassortative mate preferences. 相似文献
217.
Wouter N Leonhard Jeroen H Roelfsema Irma S Lantinga-van Leeuwen Martijn H Breuning Dorien JM Peters 《BMC biotechnology》2008,8(1):18
Background
Inducible conditional knockout animals are widely used to get insight in the function of genes and the pathogenesis of human diseases. These models frequently rely on Cre-mediated recombination of sequences flanked by Lox-P sites. To understand the consequences of gene disruption, it is essential to know the efficiency of the recombination process. 相似文献218.
219.
Esther H.-J. Kim Jane R. Petrie Lidia Motoi Marco P. Morgenstern Kevin H. Sutton Suman Mishra Lyall D. Simmons 《Food biophysics》2008,3(2):229-234
Pasta is a popular carbohydrate-based food with a low glycemic response. A continuous protein matrix which entraps starch
granules and/or limits/retards starch hydrolysis by α-amylase is thought to be an important factor in explaining the slow
digestion of starch in pasta. The characteristics of the protein matrix may also play an important role in determining the
rate of starch digestion in pasta and therefore its glycemic response. In this study, the structural and physicochemical characteristics
of the protein matrix of pasta were modified by varying the number of passes through sheeting rollers to investigate their
effect on in vitro starch digestibility. The results show that the proteins dissociated from the starch granules with increasing
sheeting passes thereby allowing an increased degree of digestion of starch. 相似文献
220.
Condition-dependent expression of secondary sexual charactersand measures of immune function in a cohort of similarly agedmale blue peafowl Pavo cristatus was used to test whether differentsexual signals provide information about different aspectsof phenotypic quality. A measure of cell-mediated immunityand the heterophillymphocyte ratio demonstrated conditiondependence, but a measure of humoral immunity was not condition
dependent. Only train length demonstrated condition-dependentexpression, while the number and the size of ocelli in thetrain did not show significant condition dependence. Althoughresidual train length (after controlling for the number andthe size of ocelli in the train) reliably reflected the magnitudeof two condition-dependent measures of immunocompetence (positively
with cell-mediated immunity and negatively with humoral immunity),residual size of ocelli was negatively related to cell-mediatedimmunity. Different features of the complex train were relatedin different ways to measures of immunocompetence. 相似文献