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21.
Adeline Arini Fabien Durant Michel Coste François Delmas Agnès Feurtet‐Mazel 《Journal of phycology》2013,49(2):361-370
While the induction of teratology by cadmium (Cd) on diatoms is already known, reversal kinetics are not well documented. This study aims to understand the viability of diatoms exhibiting teratological frustules and their reproduction capacities within a Cd‐impacted population to predict their return to normal diatom forms. We worked on a frequently encountered species in French hydrosystems: Planothidium frequentissimum (Lange‐Bertalot) Round & L. Bukhtiyarova. First, a 21‐d contamination phase highlighted increasing inductionof different teratological types in response to two levels of Cd contamination: 20 and 100 μg · L?1. The deformity counting indicated that Cd firstly generated striae and mixed teratologies, then affected the central area and the valves. Second, a 28‐d decontamination phase demonstrated the Cd depuration capacity of Planothidium frequentissimum. Cd half‐lives appeared relatively low, ~6 d for the 100 μg · L?1 condition. Moreover, the decontamination phase showed a decrease in teratology abundances, but a still incomplete recovery after 28 d. Deformations of the striae appeared to be the most sustainable phenotype since they were still significantly higher than in reference cultures at the end of the decontamination phase for both Cd cultures. 相似文献
22.
Guillaume Compain Agnès Martin-Mingot Alfonso Maresca Sebastien Thibaudeau Claudiu T. Supuran 《Bioorganic & medicinal chemistry》2013,21(6):1555-1563
A series of new, halogen containing N-substituted 4-aminobenzenesulfonamides were synthesized by using superacid HF/SbF5 chemistry and investigated as inhibitors of several human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms, that is, the cytosolic hCA I and II and, the tumor-associated transmembrane isoforms hCA IX and XII. Despite the substitution of the sulfonamide function, the presence of fluorine atom(s) in β position of the sulfonamide function strongly favors hCA inhibition. A similar effect of the β-fluorinated alkyl substitution on the amino function has been also observed. Among the tested compounds, several chlorinated derivatives have been identified as selective nanomolar, tumor-associated isoforms inhibitors. These non-primary sulfonamides probably bind in the coumarin-binding site, at the entrance of the cavity, and not to the metal ion as the primary sulfonamide inhibitors. 相似文献
23.
Adam Ahanchédé José E. F. Alfaya L. W. Andersen Didier Azam Ma. Anita M. Bautista Anne‐Laure Besnard Gregorio Bigatti Anthony Bouétard Marie‐Agnès Coutellec Eben‐Ezer B. K. Ewédjè Reiko Fuseya Ricardo GarcÍa‐Jiménez M. Haratian Olivier J. Hardy L.‐E. Holm Casey W. Hoy Eriko Koshimizu V. Loeschcke Violeta López‐Márquez Carlos A. Machado Annie Machordom C. Marchi Andrew P. Michel Claire Micheneau Omprakash Mittapalli Takahiro Nagai Nobuaki Okamoto Ying Pan F. Panitz N. Safaie Takashi Sakamoto B. Sharifnabi En‐Wei Tian Hui Yu 《Molecular ecology resources》2013,13(1):158-159
This article documents the addition of 83 microsatellite marker loci and 96 pairs of single‐nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Bembidion lampros, Inimicus japonicus, Lymnaea stagnalis, Panopea abbreviata, Pentadesma butyracea, Sycoscapter hirticola and Thanatephorus cucumeris (anamorph: Rhizoctonia solani). These loci were cross‐tested on the following species: Pentadesma grandifolia and Pentadesma reyndersii. This article also documents the addition of 96 sequencing primer pairs and 88 allele‐specific primers or probes for Plutella xylostella. 相似文献
24.
Ielham Hadad Alex Veithen Jean–Yves Springael Panagiota A. Sotiropoulou Agnès Mendes Da Costa Fran?oise Miot Robert Naeije Xavier De Deken Kathleen Mc Entee 《PloS one》2013,8(2)
Stroma cell-derived factor-1α (SDF-1α) is a cardioprotective chemokine, acting through its G-protein coupled receptor CXCR4. In experimental acute myocardial infarction, administration of SDF-1α induces an early improvement of systolic function which is difficult to explain solely by an anti-apoptotic and angiogenic effect. We wondered whether SDF-1α signaling might have direct effects on calcium transients and beating frequency.Primary rat neonatal cardiomyocytes were culture-expanded and characterized by immunofluorescence staining. Calcium sparks were studied by fluorescence microscopy after calcium loading with the Fluo-4 acetoxymethyl ester sensor. The cardiomyocyte enriched cellular suspension expressed troponin I and CXCR4 but was vimentin negative. Addition of SDF-1α in the medium increased cytoplasmic calcium release. The calcium response was completely abolished by using a neutralizing anti-CXCR4 antibody and partially suppressed and delayed by preincubation with an inositol triphosphate receptor (IP3R) blocker, but not with a ryanodine receptor (RyR) antagonist. Calcium fluxes induced by caffeine, a RyR agonist, were decreased by an IP3R blocker. Treatment with forskolin or SDF-1α increased cardiomyocyte beating frequency and their effects were additive. In vivo, treatment with SDF-1α increased left ventricular dP/dtmax.These results suggest that in rat neonatal cardiomyocytes, the SDF-1α/CXCR4 signaling increases calcium transients in an IP3-gated fashion leading to a positive chronotropic and inotropic effect. 相似文献
25.
Benjamin Salmon Claire Bardet Mayssam Khaddam Jiar Naji Benjamin R. Coyac Brigitte Baroukh Franck Letourneur Julie Lesieur Franck Decup Dominique Le Denmat Antonino Nicoletti Anne Poliard Peter S. Rowe Eric Huet Sibylle Opsahl Vital Agnès Linglart Marc D. McKee Catherine Chaussain 《PloS one》2013,8(2)
Mutations in PHEX (phosphate-regulating gene with homologies to endopeptidases on the X-chromosome) cause X-linked familial hypophosphatemic rickets (XLH), a disorder having severe bone and tooth dentin mineralization defects. The absence of functional PHEX leads to abnormal accumulation of ASARM (acidic serine- and aspartate-rich motif) peptide − a substrate for PHEX and a strong inhibitor of mineralization − derived from MEPE (matrix extracellular phosphoglycoprotein) and other matrix proteins. MEPE-derived ASARM peptide accumulates in tooth dentin of XLH patients where it may impair dentinogenesis. Here, we investigated the effects of ASARM peptides in vitro and in vivo on odontoblast differentiation and matrix mineralization. Dental pulp stem cells from human exfoliated deciduous teeth (SHEDs) were seeded into a 3D collagen scaffold, and induced towards odontogenic differentiation. Cultures were treated with synthetic ASARM peptides (phosphorylated and nonphosphorylated) derived from the human MEPE sequence. Phosphorylated ASARM peptide inhibited SHED differentiation in vitro, with no mineralized nodule formation, decreased odontoblast marker expression, and upregulated MEPE expression. Phosphorylated ASARM peptide implanted in a rat molar pulp injury model impaired reparative dentin formation and mineralization, with increased MEPE immunohistochemical staining. In conclusion, using complementary models to study tooth dentin defects observed in XLH, we demonstrate that the MEPE-derived ASARM peptide inhibits both odontogenic differentiation and matrix mineralization, while increasing MEPE expression. These results contribute to a partial mechanistic explanation of XLH pathogenesis: direct inhibition of mineralization by ASARM peptide leads to the mineralization defects in XLH teeth. This process appears to be positively reinforced by the increased MEPE expression induced by ASARM. The MEPE-ASARM system can therefore be considered as a potential therapeutic target. 相似文献
26.
Stochastic winter weather events are predicted to increase in occurrence and amplitude at northern latitudes and organisms are expected to cope through phenotypic flexibility. Small avian species wintering in these environments show acclimatization where basal metabolic rate (BMR) and maximal thermogenic capacity (MSUM) are typically elevated. However, little is known on intra-seasonal variation in metabolic performance and on how population trends truly reflect individual flexibility. Here we report intra-seasonal variation in metabolic parameters measured at the population and individual levels in black-capped chickadees (
Poecile
atricapillus
). Results confirmed that population patterns indeed reflect flexibility at the individual level. They showed the expected increase in BMR (6%) and MSUM (34%) in winter relative to summer but also, and most importantly, that these parameters changed differently through time. BMR began its seasonal increase in November, while MSUM had already achieved more than 20% of its inter-seasonal increase by October, and declined to its starting level by March, while MSUM remained high. Although both parameters co-vary on a yearly scale, this mismatch in the timing of variation in winter BMR and MSUM likely reflects different constraints acting on different physiological components and therefore suggests a lack of functional link between these parameters. 相似文献
27.
Daniel Lucas José M. Delgado-García Beatriz Escudero Carmen Albo Ana Aza Rebeca Acín-Pérez Yaima Torres Paz Moreno José Antonio Enríquez Enrique Samper Luis Blanco Alfonso Fairén Antonio Bernad Agnès Gruart 《PloS one》2013,8(1)
A definitive consequence of the aging process is the progressive deterioration of higher cognitive functions. Defects in DNA repair mechanisms mostly result in accelerated aging and reduced brain function. DNA polymerase µ is a novel accessory partner for the non-homologous end-joining DNA repair pathway for double-strand breaks, and its deficiency causes reduced DNA repair. Using associative learning and long-term potentiation experiments, we demonstrate that Polµ−/− mice, however, maintain the ability to learn at ages when wild-type mice do not. Expression and biochemical analyses suggest that brain aging is delayed in Polµ−/− mice, being associated with a reduced error-prone DNA oxidative repair activity and a more efficient mitochondrial function. This is the first example in which the genetic ablation of a DNA-repair function results in a substantially better maintenance of learning abilities, together with fewer signs of brain aging, in old mice. 相似文献
28.
Fernando Contreras Auria Albacete Pere Castellví Agnès Ca?o Bessy Benejam José Manuel Menchón 《PloS one》2016,11(2)
Background
Counterfactual thinking is a specific type of conditional reasoning that enables the generation of mental simulations of alternatives to past factual events. Although it has been broadly studied in the general population, research on schizophrenia is still scarce. The aim of the current study was to further examine counterfactual reasoning in this illness.Methods
Forty schizophrenia patients and 40 controls completed a series of tests that assessed the influence of the “causal order effect” on counterfactual thinking, and the ability to generate counterfactual thoughts and counterfactually derive inferences from a hypothetical situation. Socio-demographic and clinical characteristics, as well as neurocognitive variables, were also examined.Results
Compared to controls, the schizophrenia patients generated fewer counterfactual thoughts when faced with a simulated scenario. The pattern of response when assessing the causality effect of the order was also different between the groups, with the patients being more frequently unable to attribute any ordering of events than the control subjects. Additionally, the schizophrenia patients showed more difficulties when deriving normative counterfactual inferences from hypothetical social situations. None of the counterfactual reasoning measures was associated to any of the cognitive functions or clinical and socio-demographic variables assessed.Conclusions
A global impairment in counterfactual thinking characterizes schizophrenia patients. Because of the potential impact of such deficits on psychosocial functioning, targeting counterfactual reasoning for improvement might be considered in future treatment approaches. 相似文献29.
Metodi?D. Metodiev Kyle Thompson Charlotte?L. Alston Andrew?A.M. Morris Langping He Zarah Assouline Marlène Rio Nadia Bahi-Buisson Angela Pyle Helen Griffin Stefan Siira Aleksandra Filipovska Arnold Munnich Patrick?F. Chinnery Robert McFarland Agnès R?tig Robert?W. Taylor 《American journal of human genetics》2016,99(1):246
30.
Marine Schoeffler Anne-Laure Gaudin Fanny Ramel Odile Valette Yann Denis Wagdi Ben Hania Agnès Hirschler-Réa Alain Dolla 《Environmental microbiology》2019,21(1):360-373
Desulfovibrio species are representatives of microorganisms at the boundary between anaerobic and aerobic lifestyles, since they contain the enzymatic systems required for both sulfate and oxygen reduction. However, the latter has been shown to be solely a protective mechanism. By implementing the oxygen-driven experimental evolution of Desulfovibrio vulgaris Hildenborough, we have obtained strains that have evolved to grow with energy derived from oxidative phosphorylation linked to oxygen reduction. We show that a few mutations are sufficient for the emergence of this phenotype and reveal two routes of evolution primarily involving either inactivation or overexpression of the gene encoding heterodisulfide reductase. We propose that the oxygen respiration for energy conservation that sustains the growth of the O2-evolved strains is associated with a rearrangement of metabolite fluxes, especially NAD+/NADH, leading to an optimized O2 reduction. These evolved strains are the first sulfate-reducing bacteria that exhibit a demonstrated oxygen respiratory process that enables growth. 相似文献