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The decline in bone mass and bone strength and musculoskeletal problems associated with aging constitute a major challenge for affected individuals and the healthcare system globally. Sirtuins 1‐7 (SIRT1‐SIRT7) are a family of nicotinamide adenine dinucleotide‐dependent deacetylases with remarkable abilities to promote longevity and counteract age‐related diseases. Sirtuin knockout and transgenic models have provided novel insights into the function and signaling of these proteins in bone homeostasis. Studies have revealed that sirtuins play a critical role in normal skeletal development and homeostasis through their direct action on bone cells and that their dysregulation might contribute to different bone diseases. Preclinical studies have demonstrated that mice treated with sirtuin agonists show protection against age‐related, postmenopausal, and immobilization‐induced osteoporosis. These findings suggest that sirtuins could be potential targets for the modulation of the imbalance in bone remodeling and treatment of osteoporosis and other bone disorders. The aim of this review was to provide a comprehensive updated review of the current knowledge on sirtuin biology, focusing specifically on their roles in bone homeostasis and osteoporosis, and potential pharmacological interventions targeting sirtuins for the treatment of osteoporosis. 相似文献
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Rong Yang Eunice E. Lee Jiwoong Kim Joon H. Choi Elysha Kolitz Yating Chen Clair Crewe Nicholas J. H. Salisbury Philipp E. Scherer Clay Cockerell Taylor R. Smith Leslie Rosen Louisa Verlinden Denise A. Galloway Christopher B. Buck Mariet C. Feltkamp Christopher S. Sullivan Richard C. Wang 《PLoS pathogens》2021,17(5)
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Regina M. Sullivan Margo S. Landers Jennifer Flemming Cara Vaught Theresa A. Young H. Jonathan Polan 《Somatosensory & motor research》2013,30(2):157-162
The present series of experiments assessed how information from the whiskers controls and modulates infant rat behavior during early learning and attachment. Passive vibrissal stimulation can elicit behavioral activity in pups throughout the first two postnatal weeks, although orienting to the source of stimulation is evident only after ontogenetic emergence of whisking. In addition, while pups were capable of demonstrating learning in a classical conditioning paradigm pairing vibrissa stimulation with electric shock, no corresponding changes were detected in the anatomy of the barrel cortex as determined by cytochrome oxidase (CO) staining. Finally, the role of whiskers in a more naturalistic setting was determined in postnatal day (PN)3-5 and PN11-12 pups. Our results showed that both nipple attachment and huddling were disrupted in whisker-clipped PN3-5 pups but only marginally altered in PN11-12 pups. Together, these results suggest that the neonatal whisker system is behaviorally functional and relevant for normal mother-infant interactions, though it lacks the sophistication of a mature whisker system that evokes very specific and directed responses. 相似文献
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Lily Khadempour Valerie LeMay David Jack J?rg Bohlmann Colette Breuil 《Microbial ecology》2012,64(4):909-917
The mountain pine beetle (MPB) is a native bark beetle of western North America that attacks pine tree species, particularly lodgepole pine. It is closely associated with the ophiostomatoid ascomycetes Grosmannia clavigera, Leptographium longiclavatum, Ophiostoma montium, and Ceratocystiopsis sp.1, with which it is symbiotically associated. To develop a better understanding of interactions between beetles, fungi, and host trees, we used target-specific DNA primers with qPCR to assess the changes in fungal associate abundance over the stages of the MPB life cycle that occur in galleries under the bark of pine trees. Multivariate analysis of covariance identified statistically significant changes in the relative abundance of the fungi over the life cycle of the MPB. Univariate analysis of covariance identified a statistically significant increase in the abundance of Ceratocystiopsis sp.1 through the beetle life cycle, and pair-wise analysis showed that this increase occurs after the larval stage. In contrast, the abundance of O. montium and Leptographium species (G. clavigera, L. longiclavatum) did not change significantly through the MPB life cycle. From these results, the only fungus showing a significant increase in relative abundance has not been formally described and has been largely ignored by other MPB studies. Although our results were from only one site, in previous studies we have shown that the fungi described were all present in at least ten sites in British Columbia. We suggest that the role of Ceratocystiopsis sp.1 in the MPB system should be explored, particularly its potential as a source of nutrients for teneral adults. 相似文献
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Strategies for automated sequencing of human mitochondrial DNA directly from PCR products. 总被引:6,自引:0,他引:6
A rapid, robust and sensitive method has been developed for the amplification and direct sequencing of human mitochondrial DNA. A 403-bp hypervariable segment was amplified by two successive rounds of nested PCR. This was then sequenced by the dideoxy chain termination method using dye-labeled universal sequencing primers in conjunction with an automated DNA sequencer. This paper describes the assessment of four different strategies for this amplification and sequencing process. Optimal results were obtained by immobilizing the biotinylated PCR product on Dynabeads followed by solid-phase sequencing with Sequenase. Degraded samples and those containing trace amounts of DNA such as extracts from hair shafts can be analyzed by this method. 相似文献