319 research outputs found
Effect of repeated exposure to AQUI-S® on the viability and growth of Neoparamoeba perurans
Peer reviewedPublisher PD
Non-Lethal Sequential Individual Monitoring of Viremia in Relation to DNA Vaccination in Fish-Example Using a Salmon Alphavirus DNA Vaccine in Atlantic Salmon Salmo salar
International audienceTraditionally, commercial testing for vaccine efficacy has relied on the mass infection of vaccinated and unvaccinated animals and the comparison of mortality prevalence and incidence. For some infection models where disease does not cause mortality this approach to testing vaccine efficacy is not useful. Additionally, in fish experimental studies on vaccine efficacy and immune response the norm is that several individuals are lethally sampled at sequential timepoints, and results are extrapolated to represent the kinetics of immune and disease parameters of an individual fish over the entire experimental infection period. In the present study we developed a new approach to vaccine testing for viremic viruses in fish by following the same individuals over the course of a DNA vaccination and experimental infection through repeated blood collection and analyses. Injectable DNA vaccines are particularly efficient against viral disease in fish. To date, two DNA vaccines have been authorised for use in fish farming, one in Canada against Infectious Haemorrhagic Necrotic virus and more recently one in Europe against Salmon Pancreatic Disease virus (SPDv) subtype 3. In the current study we engineered and used an experimental DNA vaccine against SPDv subtype 1. We measured viremia using a reporter cell line system and demonstrated that the viremia phase was completely extinguished following DNA vaccination. Differences in viremia infection kinetics between fish in the placebo group could be related to subsequent antibody levels in the individual fish, with higher antibody levels at terminal sampling in fish showing earlier viremia peaks. The results indicate that sequential non-lethal sampling can highlight associations between infection traits and immune responses measured at asynchronous timepoints and, can provide biological explanations for variation in data. Similar to results observed for the SPDv subtype 3 DNA vaccine, the SPDv subtype 1 DNA vaccine also induced an interferon type 1 response after vaccination and provided high protection against SPDv under laboratory conditions when fish were challenged at 7 weeks post-vaccination
Individual measurement of gene expression in blood cells from Rainbow trout Oncorhynchus mykiss (Walbaum)
ACKNOWLEDGEMENTS This work was funded by the National Centre for the Replacement, Refinement & Reduction of Animals in Research (NC3Rs) [grant G1100675].Peer reviewedPublisher PD
Individual monitoring of immune response in Atlantic salmon Salmo salar following experimental infection with Infectious Salmon Anaemia Virus (ISAV)
This work was funded by the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs, grant G1100675). The authors are grateful to the Marine Scotland aquarium staff (Ben Williamson, Louise Feehan and Mark Paterson) for help in the experimental work. Hendrix-Genetix (formerly Landcatch Natural Selection) is also acknowledged for providing PIT tagged fish for the purpose of this project.Peer reviewedPublisher PD
A highly prevalent filamentous algal endophyte in natural populations of the sugar kelp Saccharina latissima is not detected during cultivation in Northern Brittany
International audienc
Maternal and Fetal Exposure to Bisphenol A Is Associated with Alterations of Thyroid Function in Pregnant Ewes and Their Newborn Lambs
The putative thyroid-disrupting properties of bisphenol A (BPA) highlight the need for an evaluation of fetal exposure and its consequence on the mother/newborn thyroid functions in models relevant to human. The goals of this study were to characterize in sheep a relevant model for human pregnancy and thyroid physiology, the internal exposures of the fetuses and their mothers to BPA and its main metabolite BPA-glucuronide (Gluc), and to determine to what extent it might be associated with thyroid disruption. Ewes were treated with BPA [5 mg/(kg . d) sc] or vehicle from d 28 until the end of pregnancy. Unconjugated BPA did not appear to accumulate in pregnant ewes, and its concentration was similar in the newborns and their mothers (0.13 +/- 0.02 and 0.18 +/- 0.03 nmol/ml in cord and maternal blood, respectively). In amniotic fluid and cord blood, BPA-Gluc concentrations were about 1300-fold higher than those of BPA. Total T-4 concentrations were decreased in BPA-treated pregnant ewes and in the cord and the jugular blood of their newborns (30% decrease). A similar difference was observed for free T-4 plasma concentrations in the jugular blood of the newborns. Our results show in a long-gestation species with a similar regulatory scheme of thyroid function as humans that BPA in utero exposure can be associated with hypothyroidism in the newborns. If such an effect were to be confirmed for a more relevant exposure scheme to BPA, this would constitute a major issue for BPA risk assessment
[O/Fe] Estimates for Carbon-Enhanced Metal-Poor Stars from Near-IR Spectroscopy
We report on oxygen abundances determined from medium-resolution near-IR
spectroscopy for a sample of 57 carbon-enhanced metal-poor (CEMP) stars
selected from the Hamburg/ESO survey. The majority of our program stars exhibit
oxygen-to-iron ratios in the range +0.5 < [O/Fe]< +2.0. The [O/Fe] values for
this sample are statistically compared to available high-resolution estimates
for known CEMP stars, as well as to high-resolution estimates for a set of
carbon-normal metal-poor stars. Carbon, nitrogen, and oxygen abundance patterns
for a sub-sample of these stars are compared to yield predictions for very
metal-poor asymptotic giant-branch abundances in the recent literature. We find
that the majority of our sample exhibit patterns that are consistent with
previously studied CEMP stars having s-process-element enhancements, and thus
have very likely been polluted by carbon- and oxygen-enhanced material
transferred from a metal-poor asymptotic giant-branch companion.Comment: 16 pages, 8 figures, accepted by A
A Randomized Comparison of High Clopidogrel Loading Doses in Patients With Non–ST-Segment Elevation Acute Coronary Syndromes The ALBION (Assessment of the Best Loading Dose of Clopidogrel to Blunt Platelet Activation, Inflammation and Ongoing Necrosis) Trial
ObjectivesWe sought to compare the antiplatelet effects of three clopidogrel loading doses (LDs).BackgroundAdministration of a 300-mg clopidogrel LD is beneficial in situations requiring rapid platelet inhibition. Whether higher LDs can provide further benefits remains unknown.MethodsPatients (n = 103) with non–ST-segment elevation acute coronary syndromes were randomized to receive a 300-mg, 600-mg, or 900-mg clopidogrel LD, given on top of other standard therapy (including acetylsalicylic acid). The main outcome measure was inhibition of adenosine diphosphate-induced inhibition of platelet aggregation (IPA); inhibition of platelet activation, inflammatory markers, troponin I release, and major adverse cardiac events also were evaluated; all measures were blindly evaluated.ResultsCompared with the 300-mg LD, greater doses were associated with significantly greater platelet inhibition, with dose-effect relationships observed for onset of action, maximal plateau, 24-h areas under the curves of IPA, and rates of low IPA (<10% at 6 h), using 20 μmol/l major adverse cardiac events. A significant dose-response was also observed for the vasodilator-stimulated phosphoprotein index, a measure of P2Y12receptor inhibition. Similar but nonsignificant trends were observed for troponin release and major adverse cardiac events. Bleeding rates were similar in each group.ConclusionsIn low-to-moderate risk patients with non–ST-elevation acute coronary syndromes, clopidogrel LDs >300 mg provide a faster onset of action, a higher IPA plateau, and greater reductions in platelet activation during the first 24 h. A 900-mg LD may induce a greater antiplatelet effect than 600 mg, when compared with the standard 300-mg regimen. These findings require further clinical confirmation
A highly prevalent filamentous algal endophyte in natural populations of the sugar kelp Saccharina latissima is not detected during cultivation in Northern Brittany
The sugar kelp Saccharina latissima is cultivated in Europe for food, feed and ultimately the production of chemical commodities and bioenergy. Being cultivated in the open sea, S. latissima is exposed to potentially harmful organisms, such as Laminarionema elsbetiae, a filamentous brown algal endophyte with a very high prevalence in wild populations of European S. latissima. As it was shown previously that S. latissima sporophytes get infected by L. elsbetiae very early in their life, seeding the spores on collectors and keeping them under controlled conditions during the critical time of a possible infection with filamentous endophytes could be advantageous over direct seeding techniques, where the ropes are deployed within days after seeding. We used a qPCR-assay to assess the prevalence of the endophyte L. elsbetiae in S. latissima cultivated during winter in Northern Brittany, comparing individuals from direct-seeded ropes and collector-seeded lines that were kept in laboratory conditions for different time spans. No DNA of the endophyte was detected in the samples, suggesting that either the kelps were not infected or the amount of endophytic filaments were below the detection rate of the qPCR assay. Furthermore, L. elsbetiae could not be detected in the seawater surrounding the kelp farm, indicating that L. elsbetiae is not fertile or disperses at a very small scale in Northern Brittany during the deployment time of young kelps. Our results suggest that infections of cultivated S. latissima with the endophyte L. elsbetiae might be a minor problem in kelp farms in Northern Brittany if the seeding production is kept under controlled conditions without external contamination
Interopérabilité des systèmes d'information : approches dirigées par les modèles
National audienceInformation systems are more and more often based on aggregation of other systems that must be maintained and evolved in an agile way and with no entropy creation. This is not without interoperability problems! Among others, the aim of Model-Driven Engineering (MDE) is to provide solutions for interoperability issues between systems. This paper summarizes thoughts that have come up from the specific action "Interoper- ability of information systems and model-driven engineering: What challenges? What solutions?" supported by inforsid. We propose a summary of approaches that are based on MDE and knowledge engineering and that tackle interoperability issues in the industry. Open questions and limitations that raised during the meetings are also reported
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