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931.
Kelsey D. McDermott M. Agustina Frechou Jake T. Jordan Sunaina S. Martin J. Tiago Gonçalves 《Aging cell》2023,22(9):e13924
Aging is associated with cognitive deficits, with spatial memory being very susceptible to decline. The hippocampal dentate gyrus (DG) is important for processing spatial information in the brain and is particularly vulnerable to aging, yet its sparse activity has led to difficulties in assessing changes in this area. Using in vivo two-photon calcium imaging, we compared DG neuronal activity and representations of space in young and aged mice walking on an unfamiliar treadmill. We found that calcium activity was significantly higher and less tuned to location in aged mice, resulting in decreased spatial information encoded in the DG. However, with repeated exposure to the same treadmill, both spatial tuning and information levels in aged mice became similar to young mice, while activity remained elevated. Our results show that spatial representations of novel environments are impaired in the aged hippocampus and gradually improve with increased familiarity. Moreover, while the aged DG is hyperexcitable, this does not disrupt neural representations of familiar environments. 相似文献
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International Journal of Primatology - Vertebrate predation was a vital behavior during human evolution. Some Afro-Eurasian primates, such as baboons (Papio spp.) and chimpanzees (Pan troglodytes),... 相似文献
934.
Abstract. The common waxbill Estrilda astrild was first introduced to Portugal from Africa in 1964, and has spread across much of the country and into Spain. We modelled the expansion of the common waxbill on a 20 × 20 km UTM grid in 4‐year periods from 1964 to 1999. The time variation of the square root of the occupied area shows that this expansion process is stabilizing in Portugal, and reasons for this are discussed. Several methods used to model biological expansions are not appropriate for the present case, because little quantitative data are available on the species ecology and because this expansion has been spatially heterogeneous. Instead, colonization on a grid was modelled as a function of several biophysical and spatio‐temporal variables through the fitting of a multivariate autologistic equation. This approach allows examination of the underlying factors affecting the colonization process. In the case of the common waxbill it was associated positively with its occurrence in adjacent cells, and affected negatively by altitude and higher levels of solar radiation. 相似文献
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936.
Laura Mediani Francesco Antoniani Veronica Galli Jonathan Vinet Arianna Dorotea Carr Ilaria Bigi Vadreenath Tripathy Tatiana Tiago Marco Cimino Giuseppina Leo Triana Amen Daniel Kaganovich Cristina Cereda Orietta Pansarasa Jessica Mandrioli Priyanka Tripathi Dirk Troost Eleonora Aronica Johannes Buchner Anand Goswami Jared Sterneckert Simon Alberti Serena Carra 《EMBO reports》2021,22(5)
Stress granules (SGs) are dynamic condensates associated with protein misfolding diseases. They sequester stalled mRNAs and signaling factors, such as the mTORC1 subunit raptor, suggesting that SGs coordinate cell growth during and after stress. However, the molecular mechanisms linking SG dynamics and signaling remain undefined. We report that the chaperone Hsp90 is required for SG dissolution. Hsp90 binds and stabilizes the dual‐specificity tyrosine‐phosphorylation‐regulated kinase 3 (DYRK3) in the cytosol. Upon Hsp90 inhibition, DYRK3 dissociates from Hsp90 and becomes inactive. Inactive DYRK3 is subjected to two different fates: it either partitions into SGs, where it is protected from irreversible aggregation, or it is degraded. In the presence of Hsp90, DYRK3 is active and promotes SG disassembly, restoring mTORC1 signaling and translation. Thus, Hsp90 links stress adaptation and cell growth by regulating the activity of a key kinase involved in condensate disassembly and translation restoration. 相似文献
937.
Naoya Takayama Alex Murison Shin-ichiro Takayanagi Christopher Arlidge Stanley Zhou Laura Garcia-Prat Michelle Chan-Seng-Yue Sasan Zandi Olga I. Gan Héléna Boutzen Kerstin B. Kaufmann Aaron Trotman-Grant Erwin Schoof Ken Kron Noelia Díaz John J.Y. Lee Tiago Medina Daniel D. De Carvalho Mathieu Lupien 《Cell Stem Cell》2021,28(3):488-501.e10
938.
Seasonal patterns of horse fly richness and abundance in the Pampa biome of southern Brazil 下载免费PDF全文
Fluctuations in seasonal patterns of horse fly populations were examined in rainforests of tropical South America, where the climate is seasonal. These patterns were evaluated with robust analytical models rather than identifying the main factors that influenced the fluctuations. We examined the seasonality of populations of horse flies in fields and lowland areas of the Pampa biome of southern Brazil with generalized linear models. We also investigated the diversity of these flies and the sampling effort of Malaise traps in this biome over two years. All of the 29 species had clear seasonality with regard to occurrence and abundance, but only seven species were identified as being influenced by temperature and humidity. The sampling was sufficient and the estimated diversity was 10% more than observed. Seasonal trends were synchronized across species and the populations were most abundant between September and March and nearly zero in other months. While previous studies demonstrated that seasonal patterns in population fluctuations are correlated with climatic conditions in horse fly assemblages in South America rainforests, we show a clear effect of each factor on richness and abundance and the seasonality in the prevalence of horse fly assemblages in localities of the Pampa biome. 相似文献
939.
Tatiana Tiago Barbara Hummel Federica F. Morelli Valentina Basile Jonathan Vinet Veronica Galli Laura Mediani Francesco Antoniani Silvia Pomella Matteo Cassandri Maria Giovanna Garone Beatrice Silvestri Marco Cimino Giovanna Cenacchi Roberta Costa Vincent Mouly Ina Poser Esti Yeger-Lotem Alessandro Rosa Simon Alberti Rossella Rota Anat Ben-Zvi Ritwick Sawarkar Serena Carra 《Cell death & disease》2021,12(5)