The northeastern Pacific isopod Synidotea laticauda Benedict, 1897 is reported for the first time in the French part of the English Channel. Specimens have been found in 2017 in a pebble habitat of the Seine Estuary (Normandy, France). Its occurrence in the Seine Estuary is probably related to international maritime traffic, which is important around the major seaports of the Seine Estuary: Le Havre and Rouen.

Serotonin, a highly conserved neurotransmitter, controls many biological functions in vertebrates, but also in invertebrates. Selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine, are commonly used in human medication to ease depression by affecting serotonin levels. Their residues and metabolites can be detected in the aquatic environment and its biota. They may also alter serotonin levels in aquatic invertebrates, thereby perturbing physiological functions. To investigate whether such perturbations can indeed be expected, shore crabs (Carcinus maenas) were injected either with serotonin, fluoxetine or a combination of both. Dose-dependent effects of fluoxetine ranging from 250 to 750nM were investigated. Gene expression of crustacean hyperglycemic hormone (chh) as well as moult inhibiting hormone (mih) was assessed by RT-qPCR at 2h and 12h after injection. Glucose and ecdysteroid levels in the haemolymph were monitored in regular intervals until 12h. Serotonin led to a rapid increase of chh and mih expression. On the contrary, fluoxetine only affected chh and mih expression after several hours, but kept expression levels significantly elevated. Correspondingly, serotonin rapidly increased glycaemia, which returned to normal or below normal levels after 12h. Fluoxetine, however, resulted in a persistent low-level increase of glycaemia, notably during the period when negative feedback regulation reduced glycaemia in the serotonin treated animals. Ecdysteroid levels were significantly decreased by serotonin and fluoxetine, with the latter showing less pronounced and less rapid, but longer lasting effects. Impacts of fluoxetine on glycaemia and ecdysteroids were mostly observed at higher doses (500 and 750nM) and affected principally the response dynamics, but not the amplitude of glycaemia and ecdysteroid-levels. These results suggest that psychoactive drugs are able to disrupt neuroendocrine control in decapod crustaceans, as they interfere with the normal regulation of the serotonergic system.

The Intergovernmental Panel on Climate Change (IPCC 2007-13) has developed several models that all predict a rise in mean air tem- peratures over the next decades. [...]

As it is well-established that protein extraction constitutes a crucial step for two-dimensional electrophoresis (2DE), this work was done as a prerequisite to further the study of alterations in the proteome in gills of the shore crab Carcinus maenas under contrasted environmental conditions. Because of the presence of a chitin layer, shore crab gills have an unusual structure. Consequently, they are considered as a hard tissue and represent a challenge for optimal protein extraction. In this study, we compared three published extraction procedures for subsequent applications to 2DE: the first one uses homogenization process, the second one included an additional TCA-acetone precipitation step, and finally, the third one associated grinding in liquid nitrogen (N2) and TCA-acetone precipitation. Extracted proteins were then resolved using 1DE and 2DE. Although interesting patterns were obtained using 1DE with the three methods, only the one involving grinding in liquid N2 and TCA-acetone precipitation led to proper resolution after 2DE, showing a good level of reproducibility at technical (85%) and biological (84%) levels. This last method is therefore proposed for analysis of gill proteomes in the shore crab.

Intertidal blue mussels display physiological adaptations to emersion-submersion cycle that can be impacted by response to chemicals. In order to study the interference of cellular response to pollutants on intertidal physiology, we analysed proteomic (2-DE) responses in gills of mussels exposed for 14 days to regular emersion (intertidal condition) or continuous submersion (subtidal condition) and to a mixture (B[a]P/phenantrene) of polycyclic aromatic hydrocarbons (PAHs). Antioxidant activities were measured as general stress markers. In clean context, emersion generated several over-expressions of proteins mainly involved in cytoskeleton, chaperoning, energetic metabolism and transcription regulation. Mussels exposed to PAHs showed equivalent accumulation levels of contaminants in both physiological conditions but an increased GST activity specifically in intertidal context, highlighting the high degree of stress underwent in this group, as well as over-expressions of Cu/Zn SOD and stress proteins in subtidal context. Presence of contaminants partly impacted the response to emersion: cytoskeletal rearrangements and energetic adjustments were mostly maintained whereas stress response was dramatically altered. These findings highlight the potential adverse effects of toxicants on physiological adjustments linked to air-exposure, thus suggesting to take into account in the evaluation of environmental risk the multiplicity of stresses that wild animals are likely to encounter.

We investigated the potential variability of enzymatic antioxidant activities in blue mussels Mytilus edulis from a single intertidal population but living at different tidal heights. Activity levels of antioxidant enzymes (Cu/Zn superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione transferase) were measured in the gills and digestive gland of mussels sampled at high shore (HS, air-exposure > 6 h/12 h) and low shore (LS, air-exposure < 2 h/12 h) of an intertidal zone (Yport, Normandie, France) for two consecutive autumns. In both tissues, levels of each enzymatic activity (except GST) were clearly higher in HS mussels than in LS for the two years. These results suggest an ability to acclimate the enzymatic antioxidant defences to the degree of undergone stress, confirming the importance of environmental conditions in the antioxidant responses. Therefore, the location of organisms on the shore should be taken into account in sampling for ecotoxicological studies.

Inducible antioxidant defences in marine organisms such as mussel bivalves are commonly used as biomarkers of pollutant-induced oxidative stress and their variations proposed as one of the biological effect measurements for assessment of contamination impact in aquatic environments. Among them, the copper/zinc superoxide dismutases (Cu/Zn-SODs) are metalloenzymes which play a key role in the protection of cells in case of oxidative stress. In order to observe possible variations of an antioxidant response in relation to tidal oscillations, the copper/zinc superoxide dismutase activity (Cu/Zn-SOD) was characterized in the digestive gland and gills of blue mussels sampled at high and low shore throughout the tidal cycle. Determination of SOD activity was performed on gels after isoelectro-focusing, allowing the revelation of three isoforms. In both tissues, high-shore mussels exhibited a higher level of total SOD activity than low-shore mussels. During emersion, a decrease of total SOD activity appeared in digestive gland for both groups. In high-shore mussels, the less acidic form contributed to 75% of the total activity, the second one to 20% and the more acidic one to 5% in both tissues before air exposure. During emersion, the relative contribution of the three isoforms to the total activity was markedly changed with a significant decrease in intensity of the first isoform and parallel increases in the two other ones. After re-immersion a progressive recovery of proportions of SOD isoforms was observed. In low-shore mussels, the relative contribution of the three isoforms to the total SOD activity showed similar changes. The observed variations could correspond to changes in the redox status of the mussels during tidal oscillations.

Between January 2002 and July 2003, 173 bronchoalveolar lavage (BAL) specimens from 150 patients (19 HIV-infected and 131 non-HIV-infected patients) were evaluated for identification of Pneumocystis jiroveci (formerly known as Pneumocystis carinii f. sp. hominis) using staining techniques, conventional PCR (mtLSUrRNA gene) and real-time PCR (MSG gene). Test results were compared to Pneumocystis pneumonia (PCP) confirmed by typical clinical findings and response to treatment. Sensitivity and specificity of the techniques were 60 and 100% for staining (where either one or both techniques were positive), 100 and 87.0% for conventional PCR and 100 and 84.9 % for real-time PCR, respectively. The use of a concentration of 10(3) copies of DNA per capillary of BAL as a cut-off (determined by real-time PCR) increased specificity from 84.9 to 98.6% without reducing the sensitivity of the technique. This technique is rapid (<3 h) and therefore of major interest in differentiating between asymptomatic carriage and PCP. A BAL specimen with <10(3) copies per capillary of Pneumocystis-specific DNA is more likely to indicate a chronic carrier state, but in such cases follow-up is required to ensure that the patient is not in the early stage of an active PCP.

Blue mussels (Mytilus edulis, L.) were exposed to a single dose of 1 ppb benzo[a]pyrene (BaP) under subtidal (SC) or tidal conditions (TC; 6 h immersion, 6 h emersion) in order to follow its bioaccumulation in whole mussel and mantle tissue, and to compare BaP-mediated toxicity on lipids (malonaldehyde formation, MDA) in the mantle. Rapid uptake of BaP (70–80% of BaP initially introduced in tanks) was observed in both conditions after 12 h, but subsequent depuration in clean water was slower in TC mussels. BaP levels decreased in whole tissue in both conditions between 12 and 24 h, but increased in mantle. The mantle BaP levels were similar during the first 4 days in SC and TC, but whereas they decreased in SC after 7 days, BaP was retained at high levels in mantle in TC until the end of the study (14 days). In both conditions, significant increases (P<0.05) in lipid peroxidation were observed after 4 days, but MDA levels were approximately 3 times higher in the mantle of TC than SC mussels, although BaP tissue concentrations were similar. These observations suggested that increased BaP-mediated toxicity in mantle lipid was due to the interactive effect of the tidal cycle of immersion/emersion on BaP-mediated oxidative damage.

Survival ability of Maia squinado to emersion and subsequent reimmersion was determined in winter and summer conditions. Male spider crabs were less tolerant of emersion than females. Emersion (up to 24 h in summer and to 48 h in winter) induced a marked reduction of nitrogen excretion, especially ammonia excretion. Increase in blood ammonia content was rapid and very high in summer (1750 μmol l−1), but non-lethal levels. Estimation of the body ammonia overload showed that only 30% of unexcreted ammonia accumulated in blood. The ammonia release at reimmersion indicated that ammonia also accumulated in other body compartments. Increase in blood urate content, which indirectly reduces ammonia production, was similar at both seasons. Emersed M. squinado was rapidly resorting to anaerobic metabolism, especially in summer when its blood haemocyanin content is low. A strong hyperglycemia was developed in the first 12 h of emersion at both seasons. Mortality occurring beyond 24 h of reimmersion, when the body ammonia overload is cancelled and the recovery of most of blood components is achieved, remains unexplained.

Carcinus maenas and Necora puber were exposed to air for 72 h and 18 h, respectively, at 18 °C. Changes in the free amino acid (FAA) content of their muscle, hepatopancreas and haemolymph were recorded during air-exposure and subsequent reimmersion. Muscle and hepatopancreas urate contents and haemolymph serum protein levels were also measured during emersion. In air-exposed C. maenas, the muscle FAA pool increased significantly within the first 24 h of emersion. This increase was due to an increase in the non-essential amino acid (NEAA) pool only; the essential amino acid (EAA) pool did not change. In haemolymph, the EAA pool decreased during the first 24 h of emersion, whereas the FAA and NEAA pools did not change. However, in this compartment, glutamine levels increased throughout the air-exposure period. No significant changes in FAA, NEAA and EAA contents of the hepatopancreas were observed during the 72 h emersion. In air-exposed N. puber, the FAA pools of muscle and hepatopancreas did not change, although changes in the levels of some amino acids were observed during the 18 h emersion period. In this species, large increases in both the NEAA and EAA pools in the haemolymph were recorded. High levels of urate were observed in the muscle and hepatopancreas of immersed N. puber, but no significant changes occurred during emersion. In contrast, immersed C. maenas exhibited low levels of urate in both compartments, and hepatopancreas urate levels increased slightly during emersion. Haemolymph protein content did not change in air-exposed N. puber, whereas it increased in the haemolymph of 72 h emersed C. maenas. The origin of newly formed NEAAs and their role in ammonia detoxification, particularly in C. maenas, which is able to regulate its internal ammonia levels during such a prolonged emersion, are discussed.

Glycosaminoglycans (GAGs) in the gills of an intertidal crab (Carcinus maenas) were deter mined by biochemical analysis and digestion by specific enzymes. In control (submerged) crabs, gill total GAG content was 14.58 +/- 0.97 mg.g(-1) of dry defatted weight of tissue (n = 12). Half of it consisted of sulfated GAGs: chondroitin sulfate (CS), keratan sulfate (KS), and heparan sulfate (HS) for 12%, 15%, and 24.5% of total GAGs, respectively; the other half consisted of nonsulfated GAGs: hyaluronan (HA) for 18% and a chondroitin-like compound for 30%.In crabs exposed to air for up to 72 hr, a 73% increase in gill total GAG content was observed. HA was fully responsible for the GAG increase occurring within the first 24 hr of air exposure. Both HA and chondroitin contents increased during the next 24 hr, whereas the sulfated GAGs remained at their control level. Significant changes in total sulfated GAG content occurred only after 48 hr of air exposure, and the final 32% increase was only attributable to CS. Increase in gill CS content was coupled with the main (50%) increase in gill chondroitin content.The initial increase in gill HA content is discussed in relation to the GlcNAc synthesis that we observed previously in the gills of crabs exposed to air for 24 hr. Air exposure-induced changes in the GAG population of gills and their possible implications in gill tissue homeostasis, when crabs have to face dehydration, acidosis, and internal ammonia overload, are discussed. (C) 1998;Wiley-Liss, Inc.

Carcinus maenas and Necora puber were exposed to air for 72 h and 18 h, respectively, at 18 degreesC. Nitrogen excretion, blood and muscle ammonia content and blood urate and lactate content were recorded throughout the experimental emersion and following reimmersion (recovery period). During emersion, the rate of ammonia excretion was strongly reduced in both species, while urea and amine excretion were not enhanced. Blood and muscle ammonia content increased steadily, reaching 1.3 and 10.4 mmol l-1, respectively, after an 18 h emersion in N. puber. In contrast, in C. maenas, blood ammonia levels increased slightly during the first 12 h and then remained at this level (approximately 0.12 mmol l-1) until the end of emersion. Muscle ammonia content showed a non-significant increase at 12 h, after which values returned to control values (3.3 mmol l-1) for the next 60 h. Blood urate and lactate content increased in emersed N. puber, indicating strong internal hypoxia, but urate content did not increase in C. maenas until the third day of emersion. Upon reimmersion, both species released large amounts of ammonia within a few minutes. Two different patterns of ammonia release then were observed: ammonia excretion was enhanced for a further 3 h in N. puber, whereas raised ammonia excretion rates were observed for a further 24 h in C. maenas. These patterns, the recovery of blood and muscle ammonia levels and the calculated nitrogen balance between emersed and control crabs indicated that specific processes were used to manage the nitrogen overload induced by air exposure. Whereas N. puber shows little or no ability to limit ammonia accumulation in its body, C. maenas exhibits strong regulation of its nitrogen metabolism. The probability that amino acid synthesis is involved in this regulation and whether these species use metabolic depression as a survival strategy are discussed.