Investigating the impact of remediation efforts on Hedistediversicolor in the Seine estuary using multiple levels of biological organization.

The Seine Estuary is historically one of the most contaminated estuaries in Europe. In 2002 the estuary underwent major redevelopment which emphasized environmental remediation to measure biological effects. The present study investigated the health status of the sentinel species Hediste diversicolor in the Seine estuary by comparing data from a sampling campaign immediately after the Seine underwent reconstruction and 10 years afterward. Both studies implemented multiple levels of biological organization ranging from enzymatic biomarkers to population density. Integrative modeling was used to establish a holistic status assessment for H. diversicolor in the Seine. H. diversicolor populations in the Seine estuary were impacted in both campaigns suggesting no significant improvements over the 10-year period. This interpretation however can be improved by increasing the number of reference sites used to establish the baseline natural variation, integrating additional environmental parameters into the model and measuring additional biological endpoints, such as reproductive status.

A novel methodology for the determination of biomarker baseline levels in the marine polychaete Hediste diversicolor.

Identifying environmental damage due to anthropogenic activities is a focal point for scientists and policy makers like those involved in the European Water Framework Directive (WFD). Many of these approaches focus on ecological endpoints for assessing environmental perturbations, which lead to policies emphasizing mitigation rather than prevention. Biomarkers provide early-warning indicators of stress but it is necessary to distinguish their natural variations from those induced by chemical stress. The global aim of this study was to establish a baseline assessment criterion (BAC) using historical data in a reference site to define toxicity thresholds. We have developed a multiple polynomial regression model (MPR) accounting the influence of salinity, temperature and size of individual on energetic reserves (glycogen and lipids) in the marine polychaete Hediste diversicolor. The model identified a complex, orthogonal relationship between confounding factors and glycogen and a linear relationship between lipids and size of individuals.

Induction of apoptosis in mussel Mytilus galloprovincialis gills by model cytotoxic agents.

Apoptosis signaling pathway was investigated in the marine mussel Mytilus galloprovincialis exposed to various stressors. Analyses were performed in mussels exposed to two major pollutants of the aquatic environment: tributyltin and the water soluble fraction of diesel oil, for 1 h and animals were then maintained in sea water for a recovery period of 6 and 24 h. Apoptosis was evaluated at several levels of the cell signaling cascade by measuring Bcl-xS expression, caspase-3 activity and DNA damage (Fast micromethod(®) and TUNEL techniques). H(2)O(2) was used as a control of apoptosis induction for validation of the assays. Results showed an induction of Bcl-xS expression, a protein implicated in apoptosis, after 1 h exposure to all concentrations of chemicals. Moreover, in the same manner, apoptotic DNA damage was induced with all chemicals tested. Besides, caspase 3 activity was detected after 1 h exposure to low doses of TBT and diesel oil while the high concentrations induced this protein after 6 h. The achieved data were also correlated with our previous study, demonstrating an induction of the mitogen-activated protein kinase (MAPK) activity in the mussel M. galloprovincialis exposed to the same conditions. In conclusion, this study was one of the first characterizing the MAP kinase cell signaling pathway leading to apoptosis in the mussel M. galloprovincialis exposed to chemicals. It showed for the first time that the Bcl-xS protein was present in these mussels as in other species and played a role in apoptosis mediation. Moreover, the main originality of this work was that it showed that two apoptotic pathways might be present in the mussel: a caspase 3-dependent and a caspase 3-independent pathways.

MAP kinase cell signaling pathway as biomarker of environmental pollution in the sponge Suberites domuncula.

In the present study, we analyzed the effects of two major pollutants of the environment, tributyltin (TBT) and water-accommodated fraction (WAF) of diesel oil, on MAP kinase activation, apoptosis induction and DNA damage, in the marine sponge Suberites domuncula. Our results clearly demonstrated a differential activation of the MAPKs depending on the chemicals tested. TBT induced the activation of p38 and JNK while diesel oil enhanced activation of both ERK and p38. The activation of MAPKs was observed after 1 h exposure and 6 and 24 h of recovery in seawater. In addition, DNA fragmentation, assessed by two techniques, the Fast micromethod(®) and the TUNEL assay, was detected after sponges were treated with both chemicals. Moreover, the study of caspase 3/7 activity showed that apoptosis was induced and triggered with all concentrations of TBT but only at high diesel oil concentrations. After TBT exposure, a correlation was observed between JNK activation, caspase 3 activity and DNA damage while p38 activation followed the two latter parameters at high concentrations of diesel oil, suggesting that sponges enhanced a specific apoptotic pathway depending on the xenobiotic tested. This study demonstrated a high signal response by the sponge Suberites domuncula to the tested chemicals. Cell signaling pathway studies may thus be of use in water quality biomonitoring programs.

Activation of MAP kinase signaling pathway in the mussel Mytilus galloprovincialis as biomarker of environmental pollution.

Stimulation of MAP kinase signal transduction pathway by various stressful stimuli was investigated in the marine bivalve Mytilus galloprovincialis. Analyses were performed in animals exposed in laboratory to selected pollutants and in mussels collected in winter and summer along the eastern Adriatic coast (Croatia). Effects of oxidative stress, induced by tributyltin, hydrogen peroxide and water soluble fraction of diesel fuel on the activation/phosphorylation of the three Mitogen-Activated Protein Kinases (MAPKs) p38, JNK and ERK using a newly developed ELISA procedure were evaluated. MAP kinase activation was analyzed 1h after exposure of mussels to chemical agents, and after recovery periods of 6 and 24h. Our results clearly indicated that pollutants generated different patterns of induction of the MAPK phosphorylation. Indeed, only pp38 and pJNK were activated with 11, 33 and 100 microg/L TBT, reaching a maximum activation after 6h in seawater following treatment of mussels with 11 microg/L TBT. Treatment with 0.074 and 0.222 mM H2O2 enhanced activation of both p38 and ERK. These two kinases were activated after 1h exposure, followed by a diminution after 6h of recovery in seawater and a reactivation after 24h. The levels of phosphorylated P38 and JNK were increased after mussel exposure with 7.5, 15 and 30% of water soluble fraction of diesel oil. P38 was activated concentration dependently at 1h exposure. Additionally, field study pointed out seasonal differences in MAP kinases activation as mussels collected during summer had a higher enzyme activation state than in winter, as well as sampling site differences which could be correlated to the industrial/tourism activity and environmental stresses (salinity). All the results converge towards MAP kinase signaling pathway being induced by various pollutants in M. galloprovincialis. This signaling cascade should be considered as a possible biomarker of environmental stress and pollution.

[Distal mesenteric arteritis: a rare complication of D. methylsergide treatment (author's transl)]. / Une artérite mésentérique distale. Complication rare du traitement par le D. méthylsergide.

A patient developed typical abdominal angina due to mesenteric arteritis secondary to D. methylsergide (Desernil) treatment. Multiple regular distal stenoses were revealed by arteriography, but these had completely disappeared 5 months after discontinuing treatment. Histology demonstrated fibrosis of the three tunicae with hyperelastosis. Six analogous cases due to D. methylsergide or ergotamine tartrate have been reported in the published literature, rapid regression occurring in all of them after interruption of treatment.

[Bi-apical pulmonary fibrosis during ankilosing spondylitis: A report on 5 cases (author's transl)]. / Fibrose pulmonaire bi-apicale au cours de la spondylarthrite ankylosante. A propos de 5 observations.

The authors describe 5 cases of bi-apical pulmonary fibrosis occurring during the course of ankylosing spondylitis. In 4 patients the lesions were advanced and detected during pneumological investigations. In the 5th patient, the lesions were at an early stage and were discovered during a retrospective study of 100 case-reports of patients with ankylosing spondylitis. Radiological signs were morphologically similar: localized pulmonary lesions of the two apices, of the retractile type and with a fibrous hilar framework, bullous images that were more or less extensive, raising of the two hili with compensatory distention at both bases, and pleural lesions consisting of thickening of both pleurae at the apices. The mean age of the patients at the time these lesions appear is 60 years, and they occur about 20 years after the onset of the articular disorder. These fibro-bullous lesions can be complicated by aspergillosis (20%) of pneumothorax (8%). The principal differential diagnosis is advanced tuberculous disease in the lung apices, and this explains why these patients have often been prescribed antituberculosis therapy.