75 research outputs found
Chemical Safety Assessment Using Read-Across: Assessing the Use of Novel Testing Methods to Strengthen the Evidence Base for Decision Making
Background: Safety assessment for repeated dose toxicity is one of the largest challenges in the
process to replace animal testing. This is also one of the proof of concept ambitions of SEURAT-1,
the largest ever European Union research initiative on alternative testing, co-funded by the
European Commission and Cosmetics Europe. This review is based on the discussion and outcome
of a workshop organized on initiative of the SEURAT-1 consortium joined by a group of international
experts with complementary knowledge to further develop traditional read-across and
include new approach data.
Objectives: The aim of the suggested strategy for chemical read-across is to show how a traditional
read-across based on structural similarities between source and target substance can be strengthened
with additional evidence from new approach data—for example, information from in vitro
molecular screening, “-omics” assays and computational models—to reach regulatory acceptance.
Methods: We identified four read-across scenarios that cover typical human health assessment
situations. For each such decision context, we suggested several chemical groups as examples
to prove when read-across between group members is possible, considering both chemical and
biological similarities.
Conclusions: We agreed to carry out the complete read-across exercise for at least one chemical
category per read-across scenario in the context of SEURAT-1, and the results of this exercise will
be completed and presented by the end of the research initiative in December 2015
Ovatoxin-a and Palytoxin Accumulation in Seafood in Relation to Ostreopsis cf. ovata Blooms on the French Mediterranean Coast
Dinoflagellates of the genus Ostreopsis are known to cause (often fatal) food poisoning in tropical coastal areas following the accumulation of palytoxin (PLTX) and/or its analogues (PLTX group) in crabs, sea urchins or fish. Ostreopsis spp. occurrence is presently increasing in the northern to north western Mediterranean Sea (Italy, Spain, Greece and France), probably in response to climate change. In France, Ostreopsis. cf. ovata has been associated with toxic events during summer 2006, at Morgiret, off the coast of Marseille, and a specific monitoring has been designed and implemented since 2007. Results from 2008 and 2009 showed that there is a real danger of human poisoning, as these demonstrated bioaccumulation of the PLTX group (PLTX and ovatoxin-a) in both filter-feeding bivalve molluscs (mussels) and herbivorous echinoderms (sea urchins). The total content accumulated in urchins reached 450 µg PLTX eq/kg total flesh (summer 2008). In mussels, the maximum was 230 µg eq PLTX/kg (summer 2009) compared with a maximum of 360 µg found in sea urchins during the same period at the same site. This publication brings together scientific knowledge obtained about the summer development of Ostreopsis spp. in France during 2007, 2008 and 2009
Exploitation des enquetes par sondage sur les forces de travail. 7. Importance des faibles durees de travail = Analysis of the results of the sample surveys on the labour forces. 7. Importance of the minimum duration of work. Programme of research and actions on the development of the labor market. V/522/80-FR
Poetologische Transformationen ? Die beiden Fassungen von Ilse Aichingers Roman Die größere Hoffnung unter besonderer Berücksichtigung des Magischen Realismus
This article consists in comparing meticulously both versions of Ilse Aichinger's first novel Die groBere Hoffnung, which were respectively published in 1948 and 1960. Indeed it is only recently that attention has been paid to the considerable differences existing between these two versions. Research considering this work in its historical context had until now based on the reworked text of 1960. Secondly we consider reassessing the novel from the point of view of Magical Realism, which refers according to us to both a poetic feature of numerous texts of German literature of that time (Ernst Junger, Hermann Kasack) and a concept intensely disputed in the Post-War years, notably by Hans-Werner Richter and Georg Saiko
Extent of genetic lesions of the arginine and pyrimidine biosynthetic pathways in lactobacillus plantarum, L. paraplantarum, L. pentosus, L. casei : Prevalence of CO2-dependent auxotrophs and characterization of deficient arg genes in L. plantarum
Metallothionein mRNA induction is correlated with the decrease of DNA strand breaks in cadmium exposed zebra mussels
We have previously shown that cadmium (Cd) and Benzo[a]pyrene (BaP) induced early DNA damages in zebra mussels, and that the level of DNA strand breaks (SB) returned to a basal level after 3 days of exposure to Cd. The aim of the present study was to go further in the mechanisms of Cd and BaP detoxification. For that purpose, expression of genes encoding for metallothionein (MT), Aryl Hydrocarbon Receptor (AHR), P-gP, catalase, glutathione S-transferase and Heat shock protein 70 (HSP70) proteins have been measured using RT-qPCR. Data reported here show that Cd is a strong inducer of MT and HSP70 genes, and that BaP is a strong inducer of P-gP and AHR genes. Exposure to Cd and BaP resulted in moderate changes in antioxidant enzymes mRNA. Since the increase of MT mRNA occured when the DNA SB level returned to its basal level, we can suggest that MT is implicated in cadmium detoxification
Adsorption of norovirus and ostreid herpesvirus type 1 to polymer membranes for the development of passive samplers
Aims
This study was performed to develop passive sampling methodology for the detection of two viruses in seawater in the area of shellfish production, The Norovirus (NoV), a human pathogen implicated in gastroenteritis outbreaks linked to oyster consumption and the ostreid herpesvirus type 1 (OsHV-1) a virus associated with mass mortalities of Pacific oysters.
Methods and Results
Commercially membranes were tested for their capacity to adsorb virus: Zetapor, gauze, nylon, low density polyethylene (LDPE) and Polyvinylidene difluoride (PVDF). Laboratory exposures of membranes to contaminated water samples (stool, sewage, seawater) were performed. Our data shown that the amount of NoV GII genome per membrane measured with qRT-PCR increased with the time of exposure up to 24h, for all types of membranes except gauze. After 15 days of exposure, the amount of NoV GII per membrane continued to increase only for nylon and LDPE. The amount of OsHV-1 per zetapor membrane was significantly increased as soon as 4h of exposure, and after 24 h of exposure for all types of membranes. Exposure of membranes to serial dilutions of various samples revealed that the amount of NoV GII and OsHV-1 per membrane is significantly higher in diluted samples. The detection of NoV and OsHV-1 respectively with zetapor and PVDF membranes were found to be more efficient than direct analysis of sewage and sea water Conclusions: All membranes immerged in contaminated samples adsorbed NoV GII and OsHV-1. The amount of both virus increased with the time of exposure. Zetapor and PVDF membranes seems to be more adapted to NoV GII and OsHV-1 detection respectively.
Significance and Impact of the study
Membranes tested will be used as passive samplers to improve the detection of virus in oyster production areas. Also, passive samplers could be a valuable tool for microbiome analysis with New Generation Sequencing
Les potentialités de l'imagerie radar pour la caractérisation des corridors écologiques : application au réseau bocager dans un contexte agricole
International audienc
Les potentialités de l'imagerie radar pour la caractérisation des corridors écologiques : application au réseau bocager dans un contexte agricole
International audienc
Genotoxicity and activation of cellular defenses in transplanted zebra mussels Dreissena polymorpha along the Seine river
The aim of the present study was to confirm the relevance of studying DNA adduct formation in a field study. In that context, freshwater mussels Dreissena polymorpha, collected in a reference station, were transplanted in different sites with a pollution gradient. After one and two months, mussels were collected and DNA adduct formation was analyzed using the 32P post labelling technique on both gills and digestive glands. In addition, the expression of genes involved in the detoxification system (catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), HSP70, aryl hydrocarbon receptor (AHR), P glycoprotein (PgP), metallothionein (MT)) was assessed by RT-PCR. DNA adducts were observed at amount comparable to data from literature. Increase of DNA adducts after two months of transplantation could be correlated with strong modulation of gene expression implicated in detoxification processes. Indeed, PgP and HSP70 gene expressions were similarly induced in gills and digestive glands while SOD and CAT expressions were down regulated in both tissues. AHR, GST and MT genes were differently regulated depending upon the tissue studied and the level of contamination in the different sites. We demonstrated that mussels transplanted in the different stations with pollution gradient were able to biotransform PAHs, assessed by DNA adduct formation and the high decrease of detoxification genes. Specific DNA adducts pattern obtained after one and two month mussel transplantations demonstrated the relevance of DNA adduct as biomarker of environmental pollution
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