Partial Craniofacial Cartilage Rescue in ace/fgf8 Mutants from Compensatory Signaling From the Ventricle of Danio Rerio

Examples of asymmetric organs are found throughout the animal kingdom. Whether it is superficial like the fiddler crab’s claw or within an organism like our visceral organs, asymmetries have repeatedly evolved in nature. However, the genetic and developmental origins for asymmetric organ development remain unclear, especially for superficially paired structures. Within zebrafish, a striking example of asymmetry occurs within the ace/fgf8 mutant. The pharyngeal cartilages of these mutants develop asymmetrically 35% of the time, with more cartilages developing on the left or right side of the head, but the origins of this asymmetry are unknown. A significant proportion of mutants also exhibit situs inversus, whereby the visceral organs develop on the opposite side of the body. Here we seek to understand the temporal window most sensitive to giving rise to this asymmetry, and to understand if there is a correlation between the developing heart field and pharyngeal cartilage with respect to the direction of the asymmetry. Wild type (WT) zebrafish were exposed to SU5402 during different periods of development, and heart position as well as cartilage development was observed within the developing larvae. The direction of asymmetry (i.e., left or right biased) was also recorded in ace/fgf8 mutant heart position and cartilage number to observe if there was a correlation between the two developing fields. SU5402 experiments revealed that the time window most sensitive to the development of cartilage asymmetries was during heart looping and pharyngeal arch segmentation. Furthermore, ace/fgf8 mutants exhibited a robust correlation between ventricle position and the side of cartilage asymmetry, with more cartilages forming on the side where the ventricle is located. Given the close proximity of the heart and pharyngeal cartilage fields we suggest that the heart field is influencing the developing cartilage, with signaling permeating from the developing heart to the pharyngeal mesoderm to provide a buffer on the side of the developing ventricle

Kit de mesure des micropolluants dans les eaux

Ces travaux présentent de nouvelles microélectrodes à fibre de carbone, leur procédé de préparation et leur application à l’analyse électrochimique des micropolluants organiques (MPO), ainsi que leur mise en œuvre au sein du premier prototype de kit portable. La Commission Européenne exige que la concentration maximale par composé dans l’eau destinée à la consommation humaine ne dépasse pas 0,1 μg/L et que la concentration maximale pour tous ces composés ne dépasse pas 0,5 μg/L. Nos travaux ont permis d’atteindre une limite de détection égale à la limite de qualité dans l’eau destinée à la consommation humaine, soit 0,1 μg/L, pour le paranitrophénol (PNP), alors que dans le milieu naturel les concentrations rencontrées sont de l’ordre de quelques μg/L. De plus la facilité d’utilisation de ces microélectrodes, leur versatilité et leur petite taille, nous a permis d’élaborer un kit de mesure des MPO dans les milieux aquatiques employé pour des analyses décentralisées

1er kit portable pour la mesure des micropolluants organiques (MPO) aquatiques

National audienc

Multifractal analysis of radar rainfall fields over the area of Rome

A scale-invariance analysis of space and time rainfall events monitored by meteorological radar over the area of Rome (Italy) is proposed. The study of the scale-invariance properties of intense precipitation storms, particularly important in flood forecast and risk mitigation, allows to transfer rainfall information from the large scale predictive meteorological models to the small scale hydrological rainfall-runoff models. <P style=&quot;line-height: 20px;&quot;> Precipitation events are monitored using data collected by the polarimetric Doppler radar Polar 55C (ISAC-CNR), located 15 km Southeast from downtown. The meteorological radar provides the estimates of rainfall intensity over an area of about 10 000 km² at a resolution of 2&times;2 km² in space and 5 min in time. <P style=&quot;line-height: 20px;&quot;> Many precipitation events have been observed from autumn 2001 up to now. A scale-invariance analysis is performed on some of these events with the aim at exploring the multifractal properties and at understanding their dependence on the meteorological large-scale conditions

A new motion-based tool for occupation and monitoring of residents in nursing homes

Population ageing bring new challenges in healthcare and has raised issues concerning innovative solutions to optimize the management of elderly. As recommended, new interactive tools must be accessible to users, acceptable, easy to use, motivating and useful for both residents and staff. Virtual Reality is a good candidate to fulfill these specifications. Based on our expertise in Human Computer Interaction and Neuropsychology of ageing, we are developing a platform to offer interactive activities adapted to very-old and dependent people living in nursing homes. It is based on the use of a low-cost markerless RGB-D sensor (AstraTM, Orbbec) to track user body motion. Implemented activities were designed to involve various cognitive abilities, such as sorting game, search game, ball game. In addition, a module records several biomechanical data and generates reports for caregivers. This paper aims to discuss the special needs of research context and to present the designed interaction platform

Geosmithia argillacea: an emerging agent of airway colonization in patients with cystic fibrosis?

Date du colloque&nbsp;: 06/2009</p

Intestinal cell targeting of a stable recombinant Cu–Zn SOD from Cucumis melo fused to a gliadin peptide

The mRNA encoding full length chloroplastic Cu–Zn SOD (superoxide dismutase) of Cucumis melo (Cantaloupe melon) was cloned. This sequence was then used to generate a mature recombinant SOD by deleting the first 64 codons expected to encode a chloroplastic peptide signal. A second hybrid SOD was created by inserting ten codons to encode a gliadin peptide at the N-terminal end of the mature SOD. Taking account of codon bias, both recombinant proteins were successfully expressed and produced in Escherichia coli. Both recombinant SODs display an enzymatic activity of ∼5000 U mg−1 and were shown to be stable for at least 4 h at 37 °C in biological fluids mimicking the conditions of intestinal transit. These recombinant proteins were capable in vitro, albeit at different levels, of reducing ROS-induced-apoptosis of human epithelial cells. They also stimulated production and release in a time-dependent manner of an autologous SOD activity from cells located into jejunum biopsies. Nevertheless, the fused gliadin peptide enable the recombinant Cu–Zn SOD to maintain a sufficiently sustained interaction with the intestinal cells membrane in vivo rather than being eliminated with the flow. According to these observations, the new hybrid Cu–Zn SOD should show promise in applications for managing inflammatory bowel diseases

Scedo-Select III: a new semi-selective culture medium for environmental studies

International audienc

Endoplasmic reticulum stress-induced hepatocellular death pathways mediate liver injury and fibrosis via Stimulator of Interferon Genes.

Fibrosis, driven by inflammation, marks the transition from benign to progressive stages of chronic liver diseases. Although inflammation promotes fibrogenesis, it is not known whether other events, such as hepatocyte death, are required for the development of fibrosis. Interferon Regulatory Factor 3 (IRF3) regulates hepatocyte apoptosis and production of Type-I interferons (IFNs). In the liver, IRF3 is activated via Toll-like receptor 4 (TLR4) signaling or the ER adapter, Stimulator of Interferon Genes (STING). We hypothesized that IRF3-mediated hepatocyte death is an independent determinant of chemically-induced liver fibrogenesis. To test this, we performed acute or chronic carbontetrachloride (CCl4) administration to WT, IRF3-, TRAM-, TRIF-, and STING-deficient mice. We report that acute CCl4 administration to WT mice resulted in early ER stress, activation of IRF3 and Type-I IFNs, followed by hepatocyte apoptosis and liver injury, accompanied by liver fibrosis upon repeated administration of CCl4. Deficiency of IRF3 or STING prevented hepatocyte death and fibrosis both in acute or chronic CCl4. In contrast, mice deficient in Type-I IFN receptors or in TLR4-signaling adaptors, TRAM or TRIF, upstream of IRF3, were not protected from hepatocyte death and/or fibrosis suggesting that the pro-apoptotic role of IRF3 is independent of TLR signaling in fibrosis. Hepatocyte death is required for liver fibrosis with causal involvement of STING and IRF3. Thus, our results identify that IRF3, by its association with STING in the presence of ER stress, couples hepatocyte apoptosis with liver fibrosis, and indicate that innate immune signaling modulates outcomes of liver fibrosis via modulation of hepatocyte death in the liver