A high-resolution map of the Nile tilapia genome: a resource for studying cichlids and other percomorphs

Background: The Nile tilapia (Oreochromis niloticus) is the second most farmed fish species worldwide. It is also an important model for studies of fish physiology, particularly because of its broad tolerance to an array of environments. It is a good model to study evolutionary mechanisms in vertebrates, because of its close relationship to haplochromine cichlids, which have undergone rapid speciation in East Africa. The existing genomic resources for Nile tilapia include a genetic map, BAC end sequences and ESTs, but comparative genome analysis and maps of quantitative trait loci (QTL) are still limited. Results: We have constructed a high-resolution radiation hybrid (RH) panel for the Nile tilapia and genotyped 1358 markers consisting of 850 genes, 82 markers corresponding to BAC end sequences, 154 microsatellites and 272 single nucleotide polymorphisms (SNPs). From these, 1296 markers could be associated in 81 RH groups, while 62 were not linked. The total size of the RH map is 34,084 cR3500 and 937,310 kb. It covers 88% of the entire genome with an estimated inter-marker distance of 742 Kb. Mapping of microsatellites enabled integration to the genetic map. We have merged LG8 and LG24 into a single linkage group, and confirmed that LG16-LG21 are also merged. The orientation and association of RH groups to each chromosome and LG was confirmed by chromosomal in situ hybridizations (FISH) of 55 BACs. Fifty RH groups were localized on the 22 chromosomes while 31 remained small orphan groups. Synteny relationships were determined between Nile tilapia, stickleback, medaka and pufferfish. Conclusion:The RH map and associated FISH map provide a valuable gene-ordered resource for gene mapping and QTL studies. All genetic linkage groups with their corresponding RH groups now have a corresponding chromosome which can be identified in the karyotype. Placement of conserved segments indicated that multiple inter-chromosomal rearrangements have occurred between Nile tilapia and the other model fishes. These maps represent a valuable resource for organizing the forthcoming genome sequence of Nile tilapia, and provide a foundation for evolutionary studies of East African cichlid fishes.Additional co-authors: Thomas D Kocher, Catherine Ozouf-Costaz, Jean Francois Baroiller and Francis Galiber

OVX033, a nucleocapsid-based vaccine candidate, provides broad-spectrum protection against SARS-CoV-2 variants in a hamster challenge model

Spike-based COVID-19 vaccines induce potent neutralizing antibodies but their efficacy against SARS-CoV-2 variants decreases. OVX033 is a recombinant protein composed of the full-length nucleocapsid (N) protein of SARS-CoV-2 genetically fused to oligoDOM®, a self-assembling domain which improves antigen immunogenicity. OVX033 including N as an antigenic target is proposed as new vaccine candidate providing broad-spectrum protection against sarbecoviruses. OVX033 demonstrated its ability to trigger cross-reactive T cell responses and cross-protection against three variants of SARS-CoV-2 (B.1 Europe, Delta B.1.617.2, and Omicron B.1.1.529) in a hamster challenge model, as evidenced by lower weight loss, lower lung viral loads, and reduced lung histopathological lesions

Integrated photonic-based coronagraphic systems for future space telescopes

The detection and characterization of Earth-like exoplanets around Sun-like stars is a primary science motivation for the Habitable Worlds Observatory. However, the current best technology is not yet advanced enough to reach the 10^-10 contrasts at close angular separations and at the same time remain insensitive to low-order aberrations, as would be required to achieve high-contrast imaging of exo-Earths. Photonic technologies could fill this gap, potentially doubling exo-Earth yield. We review current work on photonic coronagraphs and investigate the potential of hybridized designs which combine both classical coronagraph designs and photonic technologies into a single optical system. We present two possible systems. First, a hybrid solution which splits the field of view spatially such that the photonics handle light within the inner working angle and a conventional coronagraph that suppresses starlight outside it. Second, a hybrid solution where the conventional coronagraph and photonics operate in series, complementing each other and thereby loosening requirements on each subsystem. As photonic technologies continue to advance, a hybrid or fully photonic coronagraph holds great potential for future exoplanet imaging from space.Comment: Conference Proceedings of SPIE: Techniques and Instrumentation for Detection of Exoplanets XI, vol. 12680 (2023

Visible extreme adaptive optics on extremely large telescopes: Towards detecting oxygen in Proxima Centauri b and analogs

Looking to the future of exo-Earth imaging from the ground, core technology developments are required in visible extreme adaptive optics (ExAO) to enable the observation of atmospheric features such as oxygen on rocky planets in visible light. UNDERGROUND (Ultra-fast AO techNology Determination for Exoplanet imageRs from the GROUND), a collaboration built in Feb. 2023 at the Optimal Exoplanet Imagers Lorentz Workshop, aims to (1) motivate oxygen detection in Proxima Centauri b and analogs as an informative science case for high-contrast imaging and direct spectroscopy, (2) overview the state of the field with respect to visible exoplanet imagers, and (3) set the instrumental requirements to achieve this goal and identify what key technologies require further development.Comment: SPIE Proceeding: 2023 / 12680-6

Responses of juvenile sea bass, Dicentrarchus labrax, exposed to acute concentrations of crude oil, as assessed by molecular and physiological biomarkers.

International audienceIn the present study, juvenile sea bass were exposed for 48 and 96 h to an Arabian light crude oil and their responses were assessed at the molecular and physiological levels. The aim of the study was therefore to assess (i) the short term effects of crude oil exposure by the measurement of several molecular biomarkers, (ii) the consequences of this short term exposure on fish health by using growth and condition indices measured after a decontamination period of 28 and 26 d in seawater. Hydrocarbon petroleum concentrations was monitored during the 96 h experiments and an increase of PAH concentrations were found in fish following both exposure times. An 7-ethoxyresorufin-O-deethylase (EROD) induction was observed after 48 h of exposure, while a significant decrease in the sea bass specific growth rate in length and for the RNA:DNA ratio was observed 28 d after that exposure ceased. The EROD induction doubled after the 96 h exposure, and a significant increase in GST activities was observed. A significant decrease in the specific growth rates, the otolith recent growth, the RNA:DNA ratio and the Fulton's K condition index were then observed in sea bass 26 d after the 96 h exposure to mechanically dispersed crude oil compared to the control. The present study shows that growth and condition indices can prove useful in assessing fish health status following an oil spill. Their complementary analysis with sensitive molecular biomarkers as EROD could improve the determination of oil spill impact on fish populations

A UK Single-Center, Retrospective, Noninterventional Study of Clinical Outcomes and Costs of Two BotulinumtoxinA Treatments for Limb Spasticity

Service model changes at the North Staffordshire Rehabilitation Centre (UK) included switching spasticity treatment from onabotulinumtoxinA (onaBoNT-A) to abobotulinumtoxinA (aboBoNT-A). This noninterventional, retrospective, longitudinal study (NCT04396704) describes the clinical and economic outcomes in toxin-naive adults with spasticity who received onaBoNT-A (Cohort 1; 2015–2017) or aboBoNT-A (Cohort 2; 2017–2019). Outcomes included Goal Attainment Scale T (GAS-T) score, treatment satisfaction, quality of life (QoL; EQ-5D visual analog scale [VAS] score), and treatment costs. Adverse events were recorded for Cohort 2. Cohort 1 included 60 patients (mean [standard deviation] dose, 206.0 [98.8] U); Cohort 2 included 54 patients (753.7 [457.3] U). Mean (95% confidence interval) GAS-T scores for Cohorts 1 and 2 were 43.1 (39.3–46.9) and 47.8 (43.7–51.9) at Week 6, and 43.2 and 44.3 at Week 12, respectively. In both cohorts most patients were satisfied with treatment. At Week 12, QoL had not changed in Cohort 1 but had improved in Cohort 2 (EQ-5D VAS, −5). Mean estimated per-patient costs (in 2021) for Cohorts 1 and 2 were £315.56 and £249.25, respectively, at Week 6, and £343.20 and £273.21, respectively, at Week 12. Fifteen non–treatment-related serious adverse events and two deaths were recorded. These data may warrant a larger prospective study powered to compare outcomes of aboBoNT-A and onaBoNT-A

Complémentarité des images Pléiades et drone pour la viticulture de précision dans le cadre du programme EarthLab

National audienceThe potentiality of the Pléiades product has been assessed in the framework of the EarthLab programme set up by Telespazio France. « EarthLab Vine » aims at providing vineyard owners and wine sector with various products and services dedicated to accurate and regular monitoring of vineyards in order to improve the technical management and increase the value of the production. Telespazio France has based the EarthLab products on the different very high resolution acquisition techniques available nowadays: satellite, aerial and UAV (Unmanned Aerial Vehicle). Thanks to its resolution in the panchromatic mode, the Pléiades sensor provides images at a resolution that is compatible with the resolution required for precision agriculture activity especially viticulture where the order of magnitude of the vine elements (rows) is about 1 metre. The multispectral information is brought through a pans harpening method so as to get the information at the highest possible resolution. This step is necessary to highlight the various elements of the target scene especially the rows and inter-rows that are not distinguishable on the native resolution images (2 metres). Then the pansharpened images are processed in order to generate various products especially a vegetation index map, vegetation index maps for the rows and for the inter-rows, as well as a map showing missing or dead vine stocks. This study has shown on some vineyard plots that results obtained from the Pléiades images are spatially consistent with the results obtained from very high resolution images acquired by an UAV. Consequently, the same products can be derived from both image sets: vigour maps, row detection, missing or dead stocks. However, small detail detection such as missing or dead stocks is more difficult on the Pléiades images than on the UAV images. On vineyards with narrow rows, Pléiades pixels are very often mixed pixels composed of inter-row vegetation (grass) and vine components, which highlights the limit of the sensor resolution compared to the UAV image resolution. Consequently, UAV imagery is still more adapted in some spatial configurations. This study has shown the potentiality of Pléiades for precision viticulture applications thanks to their high resolution compared to SPOT satellite family, as well as the synergy with very high resolution imagery (UAV or aerial acquisitions). Beyond the very high resolution capabilities of Pléiades, the spatial coverage as well as the short revisit time are of high interest compared to the constraints of the aerial techniques

CX3CR1 reduces Ly6Chigh-monocyte motility within and release from the bone marrow after chemotherapy in mice

The chemokine receptor CCR2 controls the release of Ly6C monocytes from the bone marrow and their recruitment to sites of inflammation. A second chemokine receptor, CX3CR1, is differentially expressed on monocyte subsets. We examined the role of CX3CR1 in monocyte trafficking during the recovery phase after cyclophosphamide (CP)-induced myeloablation and observed that, in the absence of CCR2, Ly6C monocytes accumulated in the bone marrow and peripheral reconstitution was severely impaired compared with wild-type (WT) mice. In contrast, in the absence of CX3CR1, Ly6C monocytes accumulated less rapidly in the marrow but recovered faster in the blood and were more recruited into the spleen, suggesting an opposite action between CCR2 and CX3CR1 in myelorestoration. During the recovery phase, marrow medullar monocytes displayed lower CX3CR1 expression and reduced their adherence to coated CX3CL1. Intravital imaging of the bone marrow showed that CP treatment impacts monocyte trafficking between the parenchyma and the vasculature. Medullar monocytes in CX3CR1 mice and mice treated with a specific antagonist of CX3CR1 displayed increased mean velocity and displacement and a reduced arrest coefficient compared withWT mice. This study indicates that CX3CR1 reduces the motility of Ly6C monocytes in the bone marrow and thereby controls their release

Stem Cell-Like Properties of CK2β-down Regulated Mammary Cells

International audienceThe ubiquitous protein kinase CK2 has been demonstrated to be overexpressed in a number of human tumours. This enzyme is composed of two catalytic α or α' subunits and a dimer of β regulatory subunits whose expression levels are probably implicated in CK2 regulation. Several recent papers reported that unbalanced expression of CK2 subunits is sufficient to drive epithelial to mesenchymal transition, a process involved in cancer invasion and metastasis. Herein, through transcriptomic and miRNA analysis together with comparison of cellular properties between wild type and CK2β-knock-down MCF10A cells, we show that down-regulation of CK2β subunit in mammary epithelial cells induces the acquisition of stem cell-like properties associated with perturbed polarity, CD44high/CD24low antigenic phenotype and the ability to grow under anchorage-independent conditions. These data demonstrate that a CK2β level establishes a critical cell fate threshold in the control of epithelial cell plasticity. Thus, this regulatory subunit functions as a nodal protein to maintain an epithelial phenotype and its depletion drives breast cell stemness

Origins and unconventional behavior of neutrophils in developing zebrafish

International audienceThe first leukocytes that arise in the development of vertebrate embryos are the primitive macrophages, which differentiate in the yolk sac and then quickly invade embryonic tissues. These macrophages have been considered to constitute a separate lineage, giving rise to no other cell type. Using an in vivo photoactivatable cell tracer in the transparent zebrafish (Danio rerio) embryo, we demonstrated that this lineage also gave rise to an equal or higher number of neutrophilic granulocytes. We were surprised to find that the differentiation of these primitive neutrophils occurs only after primitive myeloid progenitors have dispersed in the tissues. By 2 days after fertilization, these neutrophils have become the major leukocyte type found wandering in the epidermis and mesenchyme. Like the primitive macrophages, all primitive and larval neutrophils express PU.1 and L-plastin and they are highly attracted to local infections, yet only a small fraction of them phagocytose microbes, and to a much lesser extent per cell than the macrophages. They are also attracted to variously stressed or malformed tissues, suggesting a wider role than antimicrobial defense