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71.
H. Karppanen Anna-Leena Sirn Alice Eskeli-Kaivosoja 《Prostaglandins & other lipid mediators》1979,17(3):385-394
Administration of PGF2α (0.2–6.4 μg) into the lateral cerebral ventricle (i.c.v.) induced dosedependent increases in blood pressure, heart rate and body temperature in urethane-anaesthetised rats, but had no effect on these parameters when the same dose range was administered intravenously. Peripheral pretreatment with sodium meclofenamate (50 mg/kg s.c.) shifted all the dose-response curves for PGF2α (i.c.v.) to the left, but indomethacin (50 mg/kg s.c.) did not significantly affect those changes. Central pretreatment with sodium meclofenamate or indomethacin (1.25 mg per rat i.c.v.) failed to modify significantly the effects of centrally administered PGF2α.The results support previous suggestions that PGF2α may participate in the central control of the cardiovascular and thermoregulatory systems, and also suggest that there may be differences in the sites and/or modes of action between sodium meclofenamate and indomethacin. 相似文献
72.
Cristiano Carlomagno Monia Cabinio Silvia Picciolini Alice Gualerzi Francesca Baglio Marzia Bedoni 《Journal of biophotonics》2020,13(3)
Alzheimer disease (AD) is the most common form of dementia in the elderly, progressively affecting the cognitive functions with a complex diagnostic procedure that limits the time for a prompt intervention. In this study we optimized a reliable protocol for the analysis of AD patients and healthy subjects' serum using the Surface Enhanced Raman Spectroscopy (SERS), taking into consideration the effect of different variables on the final spectra, analyzed and compared through multivariate analysis and correlated with hippocampus volume. As results, we demonstrated a statistical difference between the spectra collected from the two investigated groups, with an accuracy, precision and specificity of respectively 83%, 86%, and 86%. The correlation of these data with those obtained from MRI, demonstrated a direct correlation between Raman spectra and hippocampus degeneration showing the Raman Spectroscopy (RS) as a potential tool for the monitoring of AD progression and rehabilitation treatments. 相似文献
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Schooling often rests uneasily on presumed dichotomies between coverage and inquiry, skill development, and creativity. By
drawing on the often under-recognized parallels between biological evolution and human learning, this essay argues that formal
education needs and ought not to forego the unconscious exploratory processes of informal learning. Rather than posit as natural
the cultural story that formal schooling must prepare students to integrate with given cultures and foreknowable futures,
the evolutionary perspective shows that education is better thought of as preparing students to create cultures and to change,
and foster change, in relation to unknown futures. The properties that distinguish formal from informal learning—conscious
reflection and a degree of collective consensus about what constitutes knowledge at any given time—are, we argue, useful not
as ends in themselves, but as tools for maximizing, sharing, and extending unconscious, evolutionary learning. Working with
them as such offers a way out of some of education’s persistent problems. Two autobiographical case studies provide examples
of these evolutionary changes and indicate pathways of inquiry by which to pursue them. 相似文献
75.
Alice Kunzler Eduardo Antônio Kolling Jeferson Delgado da Silva-Jr Juciano Gasparotto Matheus Augusto de Bittencourt Pasquali José Cláudio Fonseca Moreira Daniel Pens Gelain 《Neurochemical research》2017,42(10):2788-2797
Retinoids (vitamin A and derivatives) are recognized as essential factors for central nervous system (CNS) development. Retinol (vitamin A) also was postulated to be a major antioxidant component of diet as it modulates reactive species (RS) production and oxidative stress in biological systems. Oxidative stress plays a major role either in pathogenesis or development of neurodegenerative diseases, or even in both. Here we investigate the role of retinol supplementation to human neuron-derived SH-SY5Y cells over RS production and biochemical markers associated to neurodegenerative diseases expressed at neuronal level in Parkinson’s disease and Alzheimer’s disease: α-synuclein, β-amyloid peptide, tau phosphorylation and RAGE. Retinol treatment (24 h) impaired cell viability and increased intracellular RS production at the highest concentrations (7 up to 20 µM). Antioxidant co-treatment (Trolox 100 µM) rescued cell viability and inhibited RS production. Furthermore, retinol (10 µM) increased the levels of α-synuclein, tau phosphorylation at Ser396, β-amyloid peptide and RAGE. Co-treatment with antioxidant Trolox inhibited the increased in RAGE, but not the effect of retinol on α-synuclein, tau phosphorylation and β-amyloid peptide accumulation. These data indicate that increased availability of retinol to neurons at levels above the cellular physiological concentrations may induce deleterious effects through diverse mechanisms, which include oxidative stress but also include RS-independent modulation of proteins associated to progression of neuronal cell death during the course of neurodegenerative diseases. 相似文献
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Ludivine Rousset Béatrice Alpha-Bazin Alice Château Jean Armengaud Thierry Clavel Odile Berge Catherine Duport 《Environmental microbiology》2020,22(12):5248-5264
Bacillus cereus is a ubiquitous endospore-forming bacterium, which mainly affects humans as a food-borne pathogen. Bacillus cereus can contaminate groundwater used to irrigate food crops. Here, we examined the ability of the emetic strain B. cereus F4810/72 to survive abiotic conditions encountered in groundwater. Our results showed that vegetative B. cereus cells rapidly evolved in a mixed population composed of endospores and asporogenic variants bearing spo0A mutations. One asporogenic variant, VAR-F48, was isolated and characterized. VAR-F48 can survive in sterilized groundwater over a long period in a vegetative form and has a competitive advantage compared to its parental strain. Proteomics analysis allowed us to quantify changes to cellular and exoproteins after 24 and 72 h incubation in groundwater, for VAR-F48 compared to its parental strain. The results revealed a significant re-routing of the metabolism in the absence of Spo0A. We concluded that VAR-F48 maximizes its energy use to deal with oligotrophy, and the emergence of spo0A-mutated variants may contribute to the persistence of emetic B. cereus in natural oligotrophic environments. 相似文献
80.
Olga A. Kildisheva Kingsley W. Dixon Fernando A. O. Silveira Ted Chapman Alice Di Sacco Andrea Mondoni Shane R. Turner Adam T. Cross 《Restoration Ecology》2020,28(Z3):S256-S265
From 50 to 90% of wild plant species worldwide produce seeds that are dormant upon maturity, with specific dormancy traits driven by species' occurrence geography, growth form, and genetic factors. While dormancy is a beneficial adaptation for intact natural systems, it can limit plant recruitment in restoration scenarios because seeds may take several seasons to lose dormancy and consequently show low or erratic germination. During this time, seed predation, weed competition, soil erosion, and seed viability loss can lead to plant re‐establishment failure. Understanding and considering seed dormancy and germination traits in restoration planning are thus critical to ensuring effective seed management and seed use efficiency. There are five known dormancy classes (physiological, physical, combinational, morphological, and morphophysiological), each requiring specific cues to alleviate dormancy and enable germination. The dormancy status of a seed can be determined through a series of simple steps that account for initial seed quality and assess germination across a range of environmental conditions. In this article, we outline the steps of the dormancy classification process and the various corresponding methodologies for ex situ dormancy alleviation. We also highlight the importance of record‐keeping and reporting of seed accession information (e.g. geographic coordinates of the seed collection location, cleaning and quality information, storage conditions, and dormancy testing data) to ensure that these factors are adequately considered in restoration planning. 相似文献