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991.
992.
Brian S. Roberts Andrew A. Hardigan Marie K. Kirby Meredith B. Fitz-Gerald C.?Mel Wilcox Robert P. Kimberly Richard M. Myers 《Nucleic acids research》2015,43(21):e145
Highly abundant microRNAs (miRNAs) in small RNA sequencing libraries make it difficult to obtain efficient measurements of more lowly expressed species. We present a new method that allows for the selective blocking of specific, abundant miRNAs during preparation of sequencing libraries. This technique is specific with little off-target effects and has no impact on the reproducibility of the measurement of non-targeted species. In human plasma samples, we demonstrate that blocking of highly abundant hsa-miR-16–5p leads to improved detection of lowly expressed miRNAs and more precise measurement of differential expression overall. Furthermore, we establish the ability to target a second abundant miRNA and to multiplex the blocking of two miRNAs simultaneously. For small RNA sequencing, this technique could fill a similar role as do ribosomal or globin removal technologies in messenger RNA sequencing. 相似文献
993.
994.
K. Kendall A. D. Roberts 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1661)
Adhesion molecules, often thought to be acting by a ‘lock and key’ mechanism, have been thought to control the adhesion of cells. While there is no doubt that a coating of adhesion molecules such as fibronectin on a surface affects cell adhesion, this paper aims to show that such surface contamination is only one factor in the equation. Starting from the baseline idea that van der Waals force is a ubiquitous attraction between all molecules, and thereby must contribute to cell adhesion, it is clear that effects from geometry, elasticity and surface molecules must all add on to the basic cell attractive force. These effects of geometry, elasticity and surface molecules are analysed. The adhesion force measured between macroscopic polymer spheres was found to be strongest when the surfaces were absolutely smooth and clean, with no projecting protruberances. Values of the measured surface energy were then about 35 mJ m−2, as expected for van der Waals attractions between the non-polar molecules. Surface projections such as abrasion roughness or dust reduced the molecular adhesion substantially. Water cut the measured surface energy to 3.4 mJ m−2. Surface active molecules lowered the adhesion still further to less than 0.3 mJ m−2. These observations do not support the lock and key concept. 相似文献
995.
Thomas W. Miller David R. Soto-Pantoja Anthony L. Schwartz John M. Sipes William G. DeGraff Lisa A. Ridnour David A. Wink David D. Roberts 《The Journal of biological chemistry》2015,290(41):24858-24874
Modulating tissue responses to stress is an important therapeutic objective. Oxidative and genotoxic stresses caused by ionizing radiation are detrimental to healthy tissues but beneficial for treatment of cancer. CD47 is a signaling receptor for thrombospondin-1 and an attractive therapeutic target because blocking CD47 signaling protects normal tissues while sensitizing tumors to ionizing radiation. Here we utilized a metabolomic approach to define molecular mechanisms underlying this radioprotective activity. CD47-deficient cells and cd47-null mice exhibited global advantages in preserving metabolite levels after irradiation. Metabolic pathways required for controlling oxidative stress and mediating DNA repair were enhanced. Some cellular energetics pathways differed basally in CD47-deficient cells, and the global declines in the glycolytic and tricarboxylic acid cycle metabolites characteristic of normal cell and tissue responses to irradiation were prevented in the absence of CD47. Thus, CD47 mediates signaling from the extracellular matrix that coordinately regulates basal metabolism and cytoprotective responses to radiation injury. 相似文献
996.
997.
Anders Nielsen Ingolf Steffan-Dewenter Catrin Westphal Olivia Messinger Simon G. Potts Stuart P. M. Roberts Josef Settele Hajnalka Szentgy?rgyi Bernard E. Vaissi��re Michalis Vaitis Michal Woyciechowski Ioannis Bazos Jacobus C. Biesmeijer Riccardo Bommarco William E. Kunin Thomas Tscheulin Ellen Lamborn Theodora Petanidou 《Ecological Research》2011,26(5):969-983
The decline of bees has raised concerns regarding their conservation and the maintenance of ecosystem services they provide to bee-pollinated wild flowers and crops. Although the Mediterranean region is a hotspot for bee species richness, their status remains poorly studied. There is an urgent need for cost-effective, reliable, and unbiased sampling methods that give good bee species richness estimates. This study aims: (a) to assess bee species richness in two common Mediterranean habitat types: semi-natural scrub (phrygana) and managed olive groves; (b) to compare species richness in those systems to that of other biogeographic regions, and (c) to assess whether six different sampling methods (pan traps, variable and standardized transect walks, observation plots and trap nests), previously tested in other European biogeographic regions, are suitable in Mediterranean communities. Eight study sites, four per habitat type, were selected on the island of Lesvos, Greece. The species richness observed was high compared to other habitat types worldwide for which comparable data exist. Pan traps collected the highest proportion of the total bee species richness across all methods at the scale of a study site. Variable and standardized transect walks detected the highest total richness over all eight study sites. Trap nests and observation plots detected only a limited fraction of the bee species richness. To assess the total bee species richness in bee diversity hotspots, such as the studied habitats, we suggest a combination of transect walks conducted by trained bee collectors and pan trap sampling. 相似文献
998.
Rhabdomyolysis-induced renal failure represents up to 15% of all cases of acute renal failure. Many studies over the past 4 decades have demonstrated that accumulation of myoglobin in the kidney is central in the mechanism leading to kidney injury. However, some discussion exists regarding the mechanism mediating this oxidant injury. Although the free-iron-catalyzed Fenton reaction has been proposed to explain the tissue injury, more recent evidence strongly suggests that the main cause of oxidant injury is myoglobin redox cycling and generation of oxidized lipids. These molecules can propagate tissue injury and cause renal vasoconstriction, two of the three main conditions associated with acute renal failure. This review presents the evidence supporting the two mechanisms of oxidative injury, describes the central role of myoglobin redox cycling in the pathology of renal failure associated with rhabdomyolysis, and discusses the value of therapeutic interventions aiming at inhibiting myoglobin redox cycling for the treatment of rhabdomyolysis-induced renal failure. 相似文献
999.
Sedman VL Kasotakis E Chen X Allen S Roberts CJ Mitraki A Tendler SJ 《Protein and peptide letters》2011,18(3):268-274
Here we present a study of five analogues of a fragment from the shaft domain of the adenovirus fibre protein that readily form fibrils under a range of conditions. Using atomic force microscopy the fibrillisation of these peptides at the liquid/solid interface utilizing ordered crystalline substrates has been investigated. Our results demonstrate that the assembly pathway at the liquid/solid interface enables only the formation of truncated fibrillar structures, which align along the substrate's underlying atomic lattice during growth. Furthermore, that the concentration and volume of solution applied can be used to directly control the density of fibrillar coverage at the surface. 相似文献
1000.
Alexandra Douglas Mahdi Altukroni Andrew A Udy Michael S Roberts Kersi Taraporewalla Jason Jenkins Jeffrey Lipman Jason A Roberts 《BMC anesthesiology》2011,11(1):1-5