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991.

Increased levels of circulating fatty acids, such as palmitic acid (PA), are associated with the development of obesity, insulin resistance, type-2 diabetes and metabolic syndrome. Furthermore, these diseases are linked to an increased risk of cancer, cardiovascular diseases, mild cognitive impairment and even Alzheimer’s disease (AD). However, the precise actions of elevated PA levels on neurons and their association with neuronal metabolic disruption that leads to the expression of pathological markers of AD, such as the overproduction and accumulation of the amyloid-β peptide, represent an area of intense investigation. A possible molecular mechanism involved in the effects of PA may be through dysfunction of the NAD+ sensor enzyme, SIRT1. Therefore, the aim of the present study was to analyze the relationship between the effects of PA metabolism on the function of SIRT1 and the upregulation of BACE1 in cultured hippocampal neurons. PA reduced the total amount of NAD+ in neurons that caused an increase in p65 K310 acetylation due to inhibition of SIRT1 activity and low protein content. Furthermore, BACE1 protein and its activity were increased, and BACE1 was relocated in neurites after PA exposure.

  相似文献   
992.
Journal of Ichthyology - Based on materials from bottom trawl surveys of 2009–2015, biomass and abundance of bottom fish of the Sea of ​​Japan between the Povorotny and Zolotoy...  相似文献   
993.
994.
Protoplasma - Green algae of the genus Zygnema form extensive mats and produce large amounts of biomass in shallow freshwater habitats. Environmental stresses including freezing may perturb these...  相似文献   
995.
Voronina  A. O.  Egorova  D. O.  Korsakova  E. S.  Plotnikova  E. G. 《Microbiology》2019,88(4):433-443
Microbiology - Molecular biological and cultivation-based approaches were used to investigate the microbial community of tehnogenic soil contaminated with poorly degradable toxic (chlorinated)...  相似文献   
996.
Paleontological Journal - Distribution of 57 ostracod species is investigated in the Quaternary sediment samples from the borehole RBH-16, drilled at the north-eastern Black Sea shelf edge off the...  相似文献   
997.
Oddi  L.  Celi  L.  Cremonese  E.  Filippa  G.  Galvagno  M.  Palestini  G.  Siniscalco  C. 《Plant and Soil》2019,434(1-2):379-395
Plant and Soil - Grasslands are among the largest ecosystems in the world and store up to 30% of the global reserves of carbon. Decomposition processes have a crucial role in maintaining carbon...  相似文献   
998.
Dispersal of offspring is a critical step in the spread of invasive species, yet dispersal patterns are seldom well studied, inhibiting effective management and ecological understanding of invasions. Dispersal patterns can be affected by characteristics of the parent plant and by climatic or site characteristics, including community vegetation structure, but these factors have not been studied in the context of plant invasion processes. Cynara cardunculus (L.) is a polycarpic perennial thistle invasive in coastal grasslands in California that produces large numbers of wind-dispersed seeds. This study quantified and compared C. cardunculus dispersal patterns in an exotic grassland (vegetated site) and an agricultural field (non-vegetated site). Seed size variation in C. cardunculus was also quantified within inflorescences, between inflorescences, and between years of production, and compared across dispersal distances. Results indicate that dispersal distance increased dramatically from less than 20 m in the vegetated site to more than 40 m in the non-vegetated site. Plants producing fewer seeds produced heavier seeds and dispersal distance decreased over time, but seed size was not related to dispersal distance, which may serve to spread the risk to seeds or seedlings across the environment. C. cardunculus has great potential for dispersal in open areas such as agricultural fields or disturbed sites, but may be limited in highly structured natural communities. Management of C. cardunculus and other wind-dispersed plant invasions may be improved by prioritizing populations with open or disturbed areas downwind and minimizing the removal of vegetation during dispersal.  相似文献   
999.

Background  

The identification of differentially expressed genes (DEGs) from Affymetrix GeneChips arrays is currently done by first computing expression levels from the low-level probe intensities, then deriving significance by comparing these expression levels between conditions. The proposed PL-LM (Probe-Level Linear Model) method implements a linear model applied on the probe-level data to directly estimate the treatment effect. A finite mixture of Gaussian components is then used to identify DEGs using the coefficients estimated by the linear model. This approach can readily be applied to experimental design with or without replication.  相似文献   
1000.

Background  

The Y model of resource allocation predicts a tradeoff between reproduction and survival. Environmental stress could affect a tradeoff between reproduction and survival, but the physiological mechanisms underlying environmental mediation of the tradeoff are largely unknown. One example is the tradeoff between starvation resistance and early fecundity. One goal of the present study was to determine if reduced early age fecundity was indeed a robust indirect response to selection for starvation resistance, by investigation of a set of D. melanogaster starvation selected lines which had not previously been characterized for age specific egg production. Another goal of the present study was to investigate a possible relationship between ovariole number and starvation resistance. Ovariole number is correlated with maximum daily fecundity in outbred D. melanogaster. Thus, one might expect that a negative genetic correlation between starvation resistance and early fecundity would be accompanied by a decrease in ovariole number.  相似文献   
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