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971.
Alzheimer's disease (AD) is characterized by cognitive disorders and alterations of behavioral traits such as anhedonia and anxiety. Contribution of nonphysiological forms of amyloid and tau peptides to the onset of neurological dysfunctions remains unclear because most preclinical models only present one of those pathological AD-related biomarkers. A more recently developed model, the TgF344-AD rat has the advantage of overexpressing amyloid and naturally developing tauopathy, thus making it close to human familial forms of AD. We showed the presence of a learning dysfunction in a reference memory test, without spatial working memory impairment but with an increase in anxiety levels and a decrease in motivation to participate in the test. In the sucrose preference test, TgF344-AD rats did not show signs of anhedonia but did not increase the volume of liquid consumed when the water was replaced by sucrose solution. These behavioral phenomena were observed at an age when tau accumulation are absent, and where amyloid deposits are predominant in the hippocampus and the entorhinal cortex. Within the hippocampus itself, amyloid accumulation is heterogenous between the subiculum, the dorsal hippocampus and the ventral hippocampus. Thus, our data demonstrated heterogeneity in the appearance of various behavioral and neurochemical markers in the TgF344-AD rat. This multivariate analysis will therefore make it possible to define the stage of the pathology, to measure its evolution and the effects of future therapeutic treatments.  相似文献   
972.
The chemical composition and in vitro biological activities of the essential oil (EO) of Micromeria macrosiphon Coss. and M. arganietorum (J. Emb.) R. Morales, two Lamiaceae endemic to south Morocco, were investigated. GC/MS analysis resulted in the identification of 36 metabolites from the EO of M. macrosiphon, 45 from M. arganietorum. Borneol was the major metabolite in both oils and together with related derivatives such as camphor, accounted for 2/3 of the EO of M. macrosiphon, 1/3 of those of M. arganietorum. Pinene and terpinene derivatives were also present in high proportions. From a chemotaxonomic point of view, the composition of the examined samples may be related to those of other species endemic to Macaronesia. Both EOs showed significant toxicity towards liver HepG2 and melanoma B16 4A5 tumor cell lines at 100 μg/mL; however, they were also cytotoxic towards S17 normal cell lines, with a selectivity index <1. No antibacterial activity was noticed against 52 strains at 100 μg/mL.  相似文献   
973.
Over the last two decades, gene therapy vectors based on wild-type Adeno-associated viruses (AAV) are safe and efficacious in numerous clinical trials and are translated into three approved gene therapy products. Concomitantly, a large body of preclinical work has illustrated the power and potential of engineered synthetic AAV capsids that often excel in terms of an organ or cell specificity, the efficiency of in vitro or in vivo gene transfer, and/or reactivity with anti-AAV immune responses. In turn, this has created a demand for new, scalable, easy-to-implement, and plug-and-play platform processes that are compatible with the rapidly increasing range of AAV capsid variants. Here, the focus is on recent advances in methodologies for downstream processing and characterization of natural or synthetic AAV vectors, comprising different chromatography techniques and thermostability measurements. To illustrate the breadth of this portfolio, two chimeric capsids are used as representative examples that are derived through forward- or backwards-directed molecular evolution, namely, AAV-DJ and Anc80. Collectively, this ever-expanding arsenal of technologies promises to facilitate the development of the next AAV vector generation derived from synthetic capsids and to accelerate their manufacturing, and to thus boost the field of human gene therapy.  相似文献   
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975.

Upwelling ecosystems exhibit strong spatio-temporal variations of environmental conditions that drive the dynamics of marine diversity and ressources. Yet little is known in these ecosystems concerning the diversity of groundfishes. We studied the effects of environment (sea surface temperature, chlorophyll a concentration and bathymetric strata) and fishing pressure on this variability in the Mauritanian Exclusive Economic Zone (MEEZ), based on abundance data collected from 2158 hauls from scientific surveys performed on the continental shelf (15–200 m) between 1997 and 2010. First, for each haul (i.e. alpha-diversity), Species richness S and Berger Parker dominance Dbp were used as proxies of two complementary groups of nine indices, belonging to three main components of diversity (species number, evenness and taxonomic diversity), identified by a principal component analysis based on Spearman correlation coefficient. Thus the set of diversity indices used in this work suggests that a single component of diversity cannot represent the biodiversity of MEEZ groundfish. Second, generalized linear models (GLM) highlighted the stability of both indices for environmental variables, fishing effort and time, while, as shown by a previous study in the MEEZ, these variables influence species composition (i.e. beta-diversity). A longitudinal gradient of S and Dbp was highlighted, with coastal strata being richer in species and abundances more evenly distributed among species than offshore strata. Overall, this study provides a baseline of groundfish diversity in the MEEZ, that is also useful for comparison to other upwelling ecosystems, and essential for monitoring its potential shifts faced to climate change.

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976.
The anthropology of cinema has been instrumental in describing the ‘unseen’ labour invested in making films. What has been less explored is film workers’ erasure of each other's concrete effort in a similar manner. This process is what I call ‘reification’. Extending Georg Lukács's reflections, I argue that the relations of production throughout the film-making process seem to be transformed into relations between things (images and sounds) in a recurring pattern. In Egypt, this transformation impacts every juncture in commercial film production, and film workers manage its continuous impact via conventional means of recognition towards their concrete work. The overarching project is to understand, on the one hand, how the serial erasure of concrete work contributes to creating the film as a commodity and, on the other hand, how workers find value in their work under conditions where their effort is consumed by the things that they produce.  相似文献   
977.
978.
979.
International Microbiology - The current plastic pollution throughout the world is a rising concern that demands the optimization of biodegradation processes. One avenue for this is to identify...  相似文献   
980.
Human activity and associated landscape modifications alter the movements of animals with consequences for populations and ecosystems worldwide. Species performing long-distance movements are thought to be particularly sensitive to human impact. Despite the increasing anthropogenic pressure, it remains challenging to understand and predict animals' responses to human activity. Here we address this knowledge gap using 1206 Global Positioning System movement trajectories of 815 individuals from 14 red deer (Cervus elaphus) and 14 elk (Cervus canadensis) populations spanning wide environmental gradients, namely the latitudinal range from the Alps to Scandinavia in Europe, and the Greater Yellowstone Ecosystem in North America. We measured individual-level movements relative to the environmental context, or movement expression, using the standardized metric Intensity of Use, reflecting both the directionality and extent of movements. We expected movement expression to be affected by resource (Normalized Difference Vegetation Index, NDVI) predictability and topography, but those factors to be superseded by human impact. Red deer and elk movement expression varied along a continuum, from highly segmented trajectories over relatively small areas (high intensity of use), to directed transitions through restricted corridors (low intensity of use). Human activity (Human Footprint Index, HFI) was the strongest driver of movement expression, with a steep increase in Intensity of Use as HFI increased, but only until a threshold was reached. After exceeding this level of impact, the Intensity of Use remained unchanged. These results indicate the overall sensitivity of Cervus movement expression to human activity and suggest a limitation of plastic responses under high human pressure, despite the species also occurring in human-dominated landscapes. Our work represents the first comparison of metric-based movement expression across widely distributed populations of a deer genus, contributing to the understanding and prediction of animals' responses to human activity.  相似文献   
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