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871.
R Fulceri R Giunti J Knudsen R Leuzzi T Kardon A Benedetti 《Biochemical and biophysical research communications》1999,264(2):409-412
We previously showed (Fulceri et al., Biochem. J. 325, 423, 1997) that the fatty acyl CoA ester palmitoyl CoA (PCoA) complexed with a molar excess of its cytosolic binding protein (ACBP) causes a discrete Ca(2+) efflux or allows Ca(2+) release by suboptimal caffeine concentrations, in the Ca(2+)-preloaded terminal cisternae fraction (TC) from rabbit skeletal muscle, by activating ryanodine receptor Ca(2+) release channels (RyRC). We show here that both effects were abolished by pretreating TC with the FKBP12 ligand rapamycin (20 microM). Moreover, rapamycin reversed the Ca(2+) release induced by combined treatment with 3 mM caffeine and the PCoA-ACBP complex. Rapamycin also reduced the Ca(2+)-releasing activity by PCoA alone. Under the above experimental conditions, rapamycin removed FKBP12 from the TC membranes, as revealed by Western blot analysis. We conclude that FKBP12 associated with RyRC in the TC membrane participates in the activation of the Ca(2+) channel by fatty acyl CoA esters. 相似文献
872.
Endre Knudsen Andreas Lindn Christiaan Both Niclas Jonzn Francisco Pulido Nicola Saino William J. Sutherland Lars A. Bach Timothy Coppack Torbjrn Ergon Phillip Gienapp Jennifer A. Gill Oscar Gordo Anders Hedenstrm Esa Lehikoinen Peter P. Marra Anders P. Mller Anna L. K. Nilsson Guillaume Pron Esa Ranta Diego Rubolini Tim H. Sparks Fernando Spina Colin E. Studds Stein A. Sther Piotr Tryjanowski Nils Chr. Stenseth 《Biological reviews of the Cambridge Philosophical Society》2011,86(4):928-946
Recent shifts in phenology in response to climate change are well established but often poorly understood. Many animals integrate climate change across a spatially and temporally dispersed annual life cycle, and effects are modulated by ecological interactions, evolutionary change and endogenous control mechanisms. Here we assess and discuss key statements emerging from the rapidly developing study of changing spring phenology in migratory birds. These well‐studied organisms have been instrumental for understanding climate‐change effects, but research is developing rapidly and there is a need to attack the big issues rather than risking affirmative science. Although we agree poorly on the support for most claims, agreement regarding the knowledge basis enables consensus regarding broad patterns and likely causes. Empirical data needed for disentangling mechanisms are still scarce, and consequences at a population level and on community composition remain unclear. With increasing knowledge, the overall support (‘consensus view’) for a claim increased and between‐researcher variability in support (‘expert opinions') decreased, indicating the importance of assessing and communicating the knowledge basis. A proper integration across biological disciplines seems essential for the field's transition from affirming patterns to understanding mechanisms and making robust predictions regarding future consequences of shifting phenologies. 相似文献
873.
Iris Starnberger Dennis Poth Pardha Saradhi Peram Stefan Schulz Miguel Vences Jette Knudsen Michael F. Barej Mark‐Oliver Rödel Manfred Walzl Walter Hödl 《Biological journal of the Linnean Society. Linnean Society of London》2013,110(4):828-838
Males of all reed frog species (Anura: Hyperoliidae) have a prominent, often colourful, gular patch on their vocal sac, which is particularly conspicuous once the vocal sac is inflated. Although the presence, shape, and form of the gular patch are well‐known diagnostic characters for these frogs, its function remains unknown. By integrating biochemical and histological methods, we found strong evidence that the gular patch is a gland producing volatile compounds, which might be emitted while calling. Volatile compounds were confirmed by gas chromatography–mass spectrometry in the gular glands in 11 species of the hyperoliid genera Afrixalus, Heterixalus, Hyperolius, and Phlyctimantis. Comparing the gular gland contents of 17 specimens of four sympatric Hyperolius species yielded a large variety of 65 compounds in species‐specific combinations. We suggest that reed frogs might use a complex combination of at least acoustic and chemical signals in species recognition and mate choice. © 2013 The Authors. Biological Journal of the Linnean Society published by John Wiley & Sons Ltd on behalf of The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 828–838. 相似文献
874.
Statistical tests for multivariate bioequivalence 总被引:3,自引:0,他引:3
875.
876.
R Knudsen Y K Lam K Folkers W Frick G D Daves D F Barofsky C Y Bowers 《Biochemical and biophysical research communications》1978,80(4):735-739
During extensive fractionation of extractives of porcine hypothalami tissue, advanced steps were monitored by RIA for the activity of the corticotropin releasing factor (CRF). Two entities with CRF-activity were observed and identified. They were 相似文献
877.
Mads Reinholdt Jensen Signe Høgslund Steen Wilhelm Knudsen Julius Nielsen Peter Rask Møller Søren Rysgaard Philip Francis Thomsen 《Diversity & distributions》2023,29(2):316-334
Aim
Greenland is one of the places on Earth where the effects of climate change are most evident. The retreat of sea ice has made East Greenland more accessible for longer periods during the year. East Greenland fjords have been notoriously difficult to study due to their remoteness, dense sea ice conditions and lack of infrastructure. As a result, biological monitoring across latitudinal gradients is scarce in East Greenland and relies on sporadic research cruises and trawl data from commercial vessels. We here aim to investigate the transition in fish and marine mammal communities from South to Northeast Greenland using environmental DNA (eDNA).Location
South to Northeast Greenland.Methods
We investigated the transition in fish and marine mammal communities from South to Northeast Greenland using eDNA metabarcoding of seawater samples. We included both surface and mesopelagic samples, collected over approximately 2400 km waterway distance, by sampling from Cape Farewell to Ella Island in August 2021.Results
We demonstrate a clear transition in biological communities from south to northeast, with detected fish and mammal species matching known distributions. Samples from the southern areas were dominated by capelin (Mallotus villosus) and redfish (Sebastes), whereas northeastern samples were dominated by polar cod (Boreogadus saida), sculpins (Myoxocephalus) and ringed seal (Pusa hispida). We provide newly generated 12S rRNA barcodes from 87 fish species, bringing the public DNA database closer to full taxonomic coverage for Greenlandic fish species for this locus.Main Conclusions
Our results demonstrate that eDNA sampling can detect latitudinal shifts in marine biological communities of the Arctic region, which can supplement traditional fish surveys in understanding species distributions and community compositions of marine vertebrates. Importantly, sampling of eDNA can be a feasible approach for detecting northward range expansions in remote areas as climate change progresses. 相似文献878.
879.
B. Almeida H. Kjeldal I. Lolas A. D. Knudsen G. Carvalho K. L. Nielsen M. T. Barreto Crespo A. Stensballe J. L. Nielsen 《Biodegradation》2013,24(5):615-630
Ibuprofen is the third most consumed pharmaceutical drug in the world. Several isolates have been shown to degrade ibuprofen, but very little is known about the biochemistry of this process. This study investigates the degradation of ibuprofen by Patulibacter sp. strain I11 by quantitative proteomics using a metabolic labelling strategy. The whole-genome of Patulibacter sp. strain I11 was sequenced to provide a species-specific protein platform for optimal protein identification. The bacterial proteomes of actively ibuprofen-degrading cells and cells grown in the absence of ibuprofen was identified and quantified by gel based shotgun-proteomics. In total 251 unique proteins were quantitated using this approach. Biological process and pathway analysis indicated a number of proteins that were up-regulated in response to active degradation of ibuprofen, some of them are known to be involved in the degradation of aromatic compounds. Data analysis revealed that several of these proteins are likely involved in ibuprofen degradation by Patulibacter sp. strain I11. 相似文献
880.