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851.
Darrabie MD Arciniegas AJ Mishra R Bowles DE Jacobs DO Santacruz L 《American journal of physiology. Endocrinology and metabolism》2011,300(5):E870-E876
Profound alterations in myocellular creatine and phosphocreatine levels are observed during human heart failure. To maintain its intracellular creatine stores, cardiomyocytes depend upon a cell membrane creatine transporter whose regulation is not clearly understood. Creatine transport capacity in the intact heart is modulated by substrate availability, and it is reduced in the failing myocardium, likely adding to the energy imbalance that characterizes heart failure. AMPK, a key regulator of cellular energy homeostasis, acts by switching off energy-consuming pathways in favor of processes that generate energy. Our objective was to determine the effects of substrate availability and AMPK activation on creatine transport in cardiomyocytes. We studied creatine transport in rat neonatal cardiomyocytes and HL-1 cardiac cells expressing the human creatine transporter cultured in the presence of varying creatine concentrations and the AMPK activator 5-aminoimidazole-4-carboxamide-1-β-d-ribonucleoside (AICAR). Transport was enhanced in cardiomyocytes following incubation in creatine-depleted medium or AICAR. The changes in transport were due to alterations in V(max) that correlated with changes in total and cell surface creatine transporter protein content. Our results suggest a positive role for AMPK in creatine transport modulation for cardiomyocytes in culture. 相似文献
852.
The frequency and intensity of extreme weather events and global temperature are rising, which poses a potential threat to
life, specifically crops, and therefore food and bioenergy supply. Reduced water availability has the most severe impact on
potential grain yield. Negative effects of transient drought stress (dry spells) can be countered by drought tolerance-inducing
chemicals. In search for useful compounds, biochemical assays are fast but limited in scope, whereas whole-plant assays are
slow, require large amounts of compounds, and are usually not concentration-related. Here we report the development of a fast,
concentration-dependent whole-plant assay using the fast growing duckweed Lemna minor L. 4-Amino-1,8-naphthalimide (1) and the imidacloprid metabolite 6-chloronicotinic acid (2) were affirmed as drought stress tolerance enhancers. Both also reduce oxidative stress-induced cell death in Arabidopsis thaliana (L.) Heynh. cell suspension culture but show differences in their mode of action. 相似文献
853.
Uhlén M Björling E Agaton C Szigyarto CA Amini B Andersen E Andersson AC Angelidou P Asplund A Asplund C Berglund L Bergström K Brumer H Cerjan D Ekström M Elobeid A Eriksson C Fagerberg L Falk R Fall J Forsberg M Björklund MG Gumbel K Halimi A Hallin I Hamsten C Hansson M Hedhammar M Hercules G Kampf C Larsson K Lindskog M Lodewyckx W Lund J Lundeberg J Magnusson K Malm E Nilsson P Odling J Oksvold P Olsson I Oster E Ottosson J Paavilainen L Persson A Rimini R Rockberg J Runeson M Sivertsson A 《Molecular & cellular proteomics : MCP》2005,4(12):1920-1932
Antibody-based proteomics provides a powerful approach for the functional study of the human proteome involving the systematic generation of protein-specific affinity reagents. We used this strategy to construct a comprehensive, antibody-based protein atlas for expression and localization profiles in 48 normal human tissues and 20 different cancers. Here we report a new publicly available database containing, in the first version, approximately 400,000 high resolution images corresponding to more than 700 antibodies toward human proteins. Each image has been annotated by a certified pathologist to provide a knowledge base for functional studies and to allow queries about protein profiles in normal and disease tissues. Our results suggest it should be possible to extend this analysis to the majority of all human proteins thus providing a valuable tool for medical and biological research. 相似文献
854.
Antonellis A Rogus JJ Canani LH Makita Y Pezzolesi MG Nam M Ng D Moczulski D Warram JH Krolewski AS 《Genomics》2002,79(3):326-332
Evaluating the potential genetic components of complex disease will likely be aided through the use of dense polymorphism maps. Previously, we reported evidence for linkage with diabetic nephropathy on chromosome 3q in a region encompassing the type 1 angiotensin II receptor (AGTR1) gene. To further investigate any role for this gene in disease onset, we set out to design a dense polymorphism map spanning the AGTR1 locus for the purpose of association studies. Toward this goal, we have developed a technique for rapid identification of polymorphisms in long stretches of genomic DNA. This approach uses long-range PCR, DNA pooling, and transposon-based DNA sequencing. Using this technique, we efficiently validated and genotyped 18 polymorphisms spanning the 60.5-kb AGTR1 locus. Our panel of polymorphisms has an average spacing of 3.2 kb and an average minor allele frequency of 24%. 相似文献
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Marc-Thorsten Hütt Marcus Kaiser Claus C. Hilgetag 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2014,369(1653)
The understanding of neural activity patterns is fundamentally linked to an understanding of how the brain''s network architecture shapes dynamical processes. Established approaches rely mostly on deviations of a given network from certain classes of random graphs. Hypotheses about the supposed role of prominent topological features (for instance, the roles of modularity, network motifs or hierarchical network organization) are derived from these deviations. An alternative strategy could be to study deviations of network architectures from regular graphs (rings and lattices) and consider the implications of such deviations for self-organized dynamic patterns on the network. Following this strategy, we draw on the theory of spatio-temporal pattern formation and propose a novel perspective for analysing dynamics on networks, by evaluating how the self-organized dynamics are confined by network architecture to a small set of permissible collective states. In particular, we discuss the role of prominent topological features of brain connectivity, such as hubs, modules and hierarchy, in shaping activity patterns. We illustrate the notion of network-guided pattern formation with numerical simulations and outline how it can facilitate the understanding of neural dynamics. 相似文献
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