To gain further insight into the conformational properties of small cyclic peptides that bind to the G-protein coupled receptor C5aR1, we report here for the first time the elucidation of three peptide solution conformations using residual dipolar couplings and NMR temperature coefficients. Each of these peptides varies by at least one amino acid, adopts a different intramolecular hydrogen bonding pattern, and has a different solution conformation. The solution conformations were used in combination with a homology structure of C5aR1 as a design template for increasing the potency of peptide leads for the C5a receptor.
View Article and Find Full Text PDFRadiation therapy for abdominopelvic malignancies often results in damage to the gastrointestinal tract (GIT) and permanent changes in bowel function. An overlooked component of the pathophysiology of radiation-induced bowel injury is the role of the gut microbiome. The goal of this research was to identify the impacts of acute radiation exposure on the GIT and gut microbiome.
View Article and Find Full Text PDFBecause of their evolutionary importance, it has been proposed that animate entities would be better remembered than inanimate entities. Although a growing body of evidence supports this hypothesis, it is still unclear whether the animacy effect persists under incidental learning conditions. Furthermore, few studies have tested the robustness of this effect in young children, with conflicting results.
View Article and Find Full Text PDFObjectives: We examine age-related differences in recollection and test the impact of words with high vs low sensory experience ratings (SER) in older and younger adults. We expected that the recollection of words with high SER would be similar in older and young adults, as they depend on knowledge, unlike recollection of words with a low SER, which would depend on executive functions.
Methods: We manipulated the sensory experience of words (high vs.
Objectives: We examine age-related differences in implicit and explicit memory tasks, and test the impact of future time perspectives on priming and cued recall.
Methods: We induced time perspective in young (limited-time perspective) and older (extended-time perspective) adults. Implicit and explicit memory tasks were performed by younger and older adults.
Contrasting irradiation of senescent cells of the diatom Thalassiosira sp. in association with the bacterium Pseudomonas stutzeri showed the effect of intensity of irradiance on the transfer of singlet oxygen ( O ) to bacteria attached to phytoplanktonic cells. Under low irradiances, O is produced slowly, favors the oxidation of algal unsaturated lipids (photodynamic effect), and limits O transfer to attached bacteria.
View Article and Find Full Text PDFSeveral studies set out to explain the presence of high proportions of photooxidation products of cis-vaccenic acid (generally considered to be of bacterial origin) in marine environments. These studies show that these oxidation products result from the transfer of singlet oxygen from senescent phytoplankton cells to the bacteria attached to them in response to irradiation by sunlight. This paper summarizes and reviews the key findings of these studies, i.
View Article and Find Full Text PDFIt has repeatedly been shown in adults that animates are remembered better than inanimates. According to the adaptive view of human memory this is due to the fact that animates are generally more important for survival than inanimates. Animacy enhances not only the quantity but also the quality of remembering.
View Article and Find Full Text PDFMemory plays an important role in the behavioral immune system (BIS; Schaller in , (2), 96-101, 2016a), a proactive immune system whose ultimate function is to make organisms avoid sources of contamination. Indeed, it has been found that objects presented next to sick people are remembered better than objects shown next to healthy people-representing a contamination effect in memory. In the present studies, we investigated this memory effect in relation to "pseudo-contaminated" sources, that is to say, people exhibiting cues ultimately evoking the threat of contamination but objectively posing no such threat in terms of disease transmission.
View Article and Find Full Text PDFThe Behavioral Immune System (BIS, Schaller & Park, 2011) is a defense system whose function is to protect against pathogen exposure. Memory is an important component of this system (Fernandes et al., 2017).
View Article and Find Full Text PDFAttractiveness judgements influence desires to initiate and maintain romantic relationships. Testosterone also predicts relationship initiation and maintenance; such effects may be driven by the hormone's modulation of attractiveness judgements, but no studies have investigated causal (and situation-dependent) effects of the hormone on these judgements. Using a placebo-controlled cross-over design, our preregistered analyses revealed order- and relationship- dependent effects: single heterosexual men judged the women as more appealing when testosterone was administered first (and placebo second), but marginally less appealing when placebo was administered first (and testosterone second).
View Article and Find Full Text PDFRecent studies have shown the presence of an abiotic electrical current across the walls of deep-sea hydrothermal chimneys, allowing the growth of electroautotrophic microbial communities. To understand the role of the different phylogenetic groups and metabolisms involved, this study focused on electrotrophic enrichment with nitrate as electron acceptor. The biofilm density, community composition, production of organic compounds, and electrical consumption were monitored by FISH confocal microscopy, qPCR, metabarcoding, NMR, and potentiostat measurements.
View Article and Find Full Text PDFThe threat of diseases varies considerably among individuals, and it has been found to be linked to various proactive or reactive behaviors. In the present studies, we investigated the impact of individual differences in the perceived vulnerability to disease (PVD) on social touch before (Study 1) or during the coronavirus disease 2019 (COVID-19) pandemic (Study 2). We also investigated the influence of personality traits in the covariation between these two dimensions.
View Article and Find Full Text PDFDuring anaerobic digestion (AD) of protein-rich wastewater, ammonium (NH) is released by amino acid degradation. High NH concentrations disturb the AD microbiome balance, leading to process impairments. The sensitivity of the AD microbiome to NH and the inhibition threshold depend on multiple parameters, especially the previous microbial acclimation to ammonium stress.
View Article and Find Full Text PDFSci Total Environ
February 2022
Nitrate (NO) removal from aquatic ecosystems involves several microbially mediated processes, including denitrification, dissimilatory nitrate reduction to ammonium (DNRA), and anaerobic ammonium oxidation (anammox), controlled by slight changes in environmental gradients. In addition, some of these processes (i.e.
View Article and Find Full Text PDFFor over two decades, researchers in the field of human social neuroendocrinology have been using single-dose pharmacological challenge protocols to determine the causal effects of testosterone on psychological, behavioural, and neural processes. Most of these single-dose administration studies have so far used (1) single-sex samples and (2) varying modes of testosterone administration (intramuscular, transdermal, sublingual, and intranasal) that produced vastly different dose-response curves. Moreover, whereas studies with male participants increased men's testosterone concentrations within the high normal physiological range, studies with women typically increased testosterone concentrations to supraphysiological levels.
View Article and Find Full Text PDFDeep-sea hydrothermal vents are extreme and complex ecosystems based on a trophic chain. We are still unsure of the identities of the first colonizers of these environments and their metabolism, but they are thought to be (hyper)thermophilic autotrophs. Here we investigate whether the electric potential observed across hydrothermal chimneys could serve as an energy source for these first colonizers.
View Article and Find Full Text PDFCompounds are morphologically complex words made of different linguistic parts. They are very prevalent in a number of languages such as French. Different psycholinguistic characteristics of compounds have been used in certain studies to investigate the mechanisms involved in compound processing (see Table 7).
View Article and Find Full Text PDFTestosterone has been suggested to influence individuals' economic decision making, yet the effects of testosterone on economic behavior are not well-understood and existing research is equivocal. In response, in three studies, we examined the extent to which testosterone affected or was associated with several different facets of economic decision making. Study 1 was a double-blind, placebo-controlled, within-subjects study examining loss aversion and risk-taking (N = 26), whereas Study 2 was a larger double-blind, placebo-controlled, between-subjects study examining loss aversion and risk-taking behavior (N = 117).
View Article and Find Full Text PDFIn the framework of the GreenEdge Project (whose the general objective is to understand the dynamic of the phytoplankton spring bloom in Arctic Ocean), lipid composition and viability and stress state of bacteria were monitored in sea ice and suspended particulate matter (SPM) samples collected in 2016 along a transect from sea ice to open water in Baffin Bay (Arctic Ocean). Lipid analyses confirmed the dominance of diatoms in the bottommost layer of ice and suggested (i) the presence of a strong proportion of micro-zooplankton in SPM samples collected at the western ice covered St 403 and St 409 and (ii) a high proportion of macro-zooplankton (copepods) in SPM samples collected at the eastern ice covered St 413 and open water St 418. The use of the propidium monoazide (PMA) method allowed to show a high bacterial mortality in sea ice and in SPM material collected in shallower waters at St 409 and St 418.
View Article and Find Full Text PDFLentic ecosystems play a major role in the global carbon cycling but the understanding of the environmental determinants of lake metabolism is still limited, notably in small artificial lakes. Here the effects of environmental conditions on lake metabolism and CO and CH emissions were quantified in 11 small artificial gravel pit lakes covering a gradient of ecosystem maturity, ranging from young oligotrophic to older, hypereutrophic lakes. The diffusive fluxes of CO and CH ranged from -30.
View Article and Find Full Text PDFWe provide normative data for a new set of 313 colourised line drawings. The drawings were standardised on name agreement ( = 60 participants), image agreement ( = 34), conceptual familiarity ( = 36), age of acquisition ( = 35), and imageability ( = 35). Objective visual complexity measures are given for the pictures, and objective word frequencies are provided for the modal names of the drawings.
View Article and Find Full Text PDFPhotosynthetic microbial mats are stable, self-supported communities. Due to their coastal localization, these mats are frequently exposed to hydrocarbon contamination and are able to grow on it. To decipher how this contamination disturbs the functioning of microbial mats, we compared two mats: a contaminated mat exposed to chronic petroleum contamination and a reference mat.
View Article and Find Full Text PDFAlanine-serine-cysteine transporter 2 (ASCT2, SLC1A5) is the primary transporter of glutamine in cancer cells and regulates the mTORC1 signaling pathway. The SLC1A5 function involves finely tuned orchestration of two domain movements that include the substrate-binding transport domain and the scaffold domain. Here, we present cryo-EM structures of human SLC1A5 and its complex with the substrate, L-glutamine in an outward-facing conformation.
View Article and Find Full Text PDFLike other animals, humans are sensitive to facial cues of threat. Recent evidence suggests that we use this information to dynamically calibrate competitive decision-making over resources, ceding more to high-threat individuals (who appear more willing/able to retaliate) and keeping more from low-threat individuals. Little is known, however, about the biological factors that support such threat assessment and decision-making systems.
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