Rare earth elements accumulation and patterns in abiotic and biotic compartments of a large river system influenced by natural and anthropogenic sources in Eastern Canada.

The mobilization of rare earth elements (REEs) in aquatic ecosystems is expected to rise significantly due to intensified exploitation, erosion, and climate change. As a result, more attention has been brought to study their environmental fate. However, our ability to assess contamination risks in freshwater organisms remains limited due to scarce data on the composition and accumulation of REEs.

Genomic analysis of a second rainbow trout line (Arlee) leads to an extended description of the IGH VDJ gene repertoire.

High-throughput sequencing technologies brought a renewed interest for immune repertoires. Fish Ab and B cell repertoires are no exception, and their comprehensive analysis can both provide new insights into poorly understood immune mechanisms, and identify markers of protection after vaccination. However, the lack of genomic description and standardized nomenclature of IG genes hampers accurate annotation of Ig mRNA deep sequencing data.

Combined effects of temperature increase and immune challenge in two wild gudgeon populations.

In the context of global changes, aquatic ecosystems are increasingly exposed to multiple stressors that can have unexpected interactive effects on aquatic organisms. Among these stressors, the occurrence of heat waves and pathogens is changing rapidly in freshwater rivers, but their combined effects on fish health are still understudied. In this study, we experimentally tested the crossed effects of increased temperature (mimicking a heat wave) and a standardized immune challenge (mimicking a parasite attack) on wild gudgeon (Gobio occitaniae) physiology and behaviour across biological levels from molecules to the whole individual.

[An urban health workgroup in northern Marseille: the experiment of a health and living environment network].

The réseau santé cadre de vie (health and living environment network) was created in 2007 by the Atelier Santé Ville (Urban Health Workgroup) with the support of the CUCS in a run-down residential area of Marseille. Its aim is to improve the health of residents living in the private jointly-owned property of Kallisté by acting on factors determining lifestyle practices and the living environment. With the help of associations and institutions involved in the local network, a range of activities targeting local residents have been developed to promote access to healthcare and prevention and improve the living environment.

Spatial heterogeneity of periphytic microbial communities in a small pesticide-polluted river.

Spatial variability in the microbial community composition of river biofilms was investigated in a small river using two spatial scales: one monitored the upstream-downstream pesticide contamination gradient, referred to as the 'between-section variability', and the other monitored a 100-m longitudinal transect (eight sampling sites per section) within each sampling section, referred to as the 'within-section variability'. Periphyton samples were collected in spring and winter on artificial substrates placed in the main channel of the river. Denaturing gradient gel electrophoresis (DGGE) was used to assess the prokaryotic and eukaryotic community richness and diversity, and HPLC pigment analysis to assess the global taxonomic composition of the photoautotrophic community.

Genetic diversity of small eukaryotes in lakes differing by their trophic status.

Small eukaryotes, cells with a diameter of less than 5 mum, are fundamental components of lacustrine planktonic systems. In this study, small-eukaryote diversity was determined by sequencing cloned 18S rRNA genes in three libraries from lakes of differing trophic status in the Massif Central, France: the oligotrophic Lake Godivelle, the oligomesotrophic Lake Pavin, and the eutrophic Lake Aydat. This analysis shows that the least diversified library was in the eutrophic lake (12 operational taxonomic units [OTUs]) and the most diversified was in the oligomesotrophic lake (26 OTUs).

IMGT/PhyloGene: an on-line tool for comparative analysis of immunoglobulin and T cell receptor genes.

IMGT/PhyloGene is an on-line software package for comparative analysis of immunoglobulin (IG) and T cell receptor (TR) variable genes of all vertebrate species, newly implemented in IMGT, the international ImMunoGeneTics information system ((R)). IMGT/PhyloGene is strongly associated with the IMGT gene and allele nomenclature and with the IMGT unique numbering for V-REGION, which directly creates standardized alignments from IMGT reference sequences. IMGT/PhyloGene is the first tool to use the IMGT expertized and standardized data for automated comparative analyses, and the first on-line software package for phylogenetic reconstruction to be integrated to a sequence database.