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1.
Mar Environ Res ; 119: 100-13, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27262668

RESUMO

Meiofauna abundance, biomass and individual size were studied in mangrove sediments subjected to shrimp farm effluents in New Caledonia. Two strategies were developed: i) meiofauna examination during the active (AP) and the non-active (NAP) periods of the farm in five mangrove stands characteristics of the mangrove zonation along this coastline, ii) meiofauna examination every two months during one year in the stand the closest to the pond (i.e. Avicennia marina). Thirteen taxonomic groups of meiofauna were identified, with nematodes and copepods being the most abundant ones. Meiofauna abundance and biomass increased from the land side to the sea side of the mangrove probably as a result of the increased length of tidal immersion. Abundance of total meiofauna was not significantly different before and after the rearing period. However, the effluent-receiving mangrove presented twice the meiofauna abundance and biomass than the control one. Among rare taxa, mites appeared extremely sensitive to this perturbation.


Assuntos
Aquicultura , Organismos Aquáticos/fisiologia , Águas Residuárias/toxicidade , Áreas Alagadas , Monitoramento Ambiental , Nova Caledônia , Águas Residuárias/análise , Águas Residuárias/estatística & dados numéricos
2.
Mar Pollut Bull ; 93(1-2): 103-20, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25758645

RESUMO

In New Caledonia, semi-intensive shrimp farms release untreated effluents into the mangrove. Foraminiferal assemblages were analyzed for assessing the impact of effluent release on the benthic compartment. Comparison was made between samples collected (1) in an effluent receiving mangrove before and after the rearing cycle, and (2) for one-year monitoring an effluent receiving and a control mangrove. The distribution of foraminiferal assemblages was primarily driven by the gradient between Rhizophora stands and salt-flats, related to salinity and tidal elevation, and by seasonal cycles. The potential impact of effluent release was due to the combined effects of normal-saline effluents on surface salinity, and of nutrient input and microbial stimulation on food availability. Foraminiferal assemblages did not indicate a substantial impact of farm effluents and suggest that semi-intensive shrimp farming using mangrove for effluent discharge may appear as a sustainable solution in New Caledonia, when considering only the impact on the mangrove itself.


Assuntos
Aquicultura , Monitoramento Ambiental/métodos , Foraminíferos/classificação , Poluição da Água/análise , Animais , Crustáceos , Foraminíferos/crescimento & desenvolvimento , Nova Caledônia , Rhizophoraceae/fisiologia , Poluição da Água/estatística & dados numéricos , Áreas Alagadas
3.
mBio ; 4(3): e00052-13, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-23674611

RESUMO

UNLABELLED: Metabolic interactions with endosymbiotic photosynthetic dinoflagellate Symbiodinium spp. are fundamental to reef-building corals (Scleractinia) thriving in nutrient-poor tropical seas. Yet, detailed understanding at the single-cell level of nutrient assimilation, translocation, and utilization within this fundamental symbiosis is lacking. Using pulse-chase (15)N labeling and quantitative ion microprobe isotopic imaging (NanoSIMS; nanoscale secondary-ion mass spectrometry), we visualized these dynamic processes in tissues of the symbiotic coral Pocillopora damicornis at the subcellular level. Assimilation of ammonium, nitrate, and aspartic acid resulted in rapid incorporation of nitrogen into uric acid crystals (after ~45 min), forming temporary N storage sites within the dinoflagellate endosymbionts. Subsequent intracellular remobilization of this metabolite was accompanied by translocation of nitrogenous compounds to the coral host, starting at ~6 h. Within the coral tissue, nitrogen is utilized in specific cellular compartments in all four epithelia, including mucus chambers, Golgi bodies, and vesicles in calicoblastic cells. Our study shows how nitrogen-limited symbiotic corals take advantage of sudden changes in nitrogen availability; this opens new perspectives for functional studies of nutrient storage and remobilization in microbial symbioses in changing reef environments. IMPORTANCE: The methodology applied, combining transmission electron microscopy with nanoscale secondary-ion mass spectrometry (NanoSIMS) imaging of coral tissue labeled with stable isotope tracers, allows quantification and submicrometric localization of metabolic fluxes in an intact symbiosis. This study opens the way for investigations of physiological adaptations of symbiotic systems to nutrient availability and for increasing knowledge of global nitrogen and carbon biogeochemical cycling.


Assuntos
Alveolados/fisiologia , Antozoários/fisiologia , Antozoários/parasitologia , Nitrogênio/metabolismo , Simbiose , Alveolados/química , Alveolados/metabolismo , Animais , Antozoários/química , Marcação por Isótopo , Compostos de Nitrogênio/metabolismo , Isótopos de Nitrogênio/metabolismo , Organelas/química , Espectrometria de Massa de Íon Secundário
4.
Aquat Toxicol ; 108: 130-40, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22265613

RESUMO

Since sediments have the potential to form associations with several classes of pollutants, they have been recognized as a possible and significant source of contamination for the benthic environment. Flatfish maintain a close association with sediments for food and cover, and are therefore more likely to be exposed to contaminated sediments, especially in coastal areas (e.g. nursery grounds). The assessment of these potential biological effects involves the use of adapted biomonitoring tools. The main objective of this study was to assess and compare the response of several physiological biomarkers measured on juvenile turbot (Scophthalmus maximus) exposed to contaminated sediments. Sediments were collected from three stations in a harbour in northern France (Boulogne-sur-Mer), in an anthropogenic French estuary (the Seine), and in a reference site (exposed sandy beach of Wimereux). Unexposed lab-reared juvenile turbots were exposed to sediments for 7 and 21 days in laboratory conditions. Sediments were analysed for metals, PAH and PCB contamination. Several fish growth and condition indices were individually analysed in fish according to the chemical contaminant availability in sediment, the metal concentrations in gills and the estimation of PAH metabolites in their bile. Significant decreases in growth rates, morphometric index, RNA:DNA ratio and the lipid storage index, based on the ratio of the quantity of triacylglycerols on sterols (TAG:ST), were observed with increasing level of chemical contamination. This decrease in the fish's physiological status could be related to the significant increase of several metal concentrations in contaminated fish gills and the significant increase of PAH metabolites in bile. In a field situation, such a reduction in growth and energetic status of juvenile fish could dramatically decrease their over-winter survival in contaminated nursery grounds.


Assuntos
Linguados/fisiologia , Sedimentos Geológicos/química , Crescimento e Desenvolvimento/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Bile/química , Biomarcadores/análise , Restrição Calórica , Linguados/crescimento & desenvolvimento , Sedimentos Geológicos/análise , Brânquias/química , Metais Pesados/análise , Metais Pesados/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/análise
5.
Chemosphere ; 87(7): 692-702, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22236592

RESUMO

In the present study, juvenile sea bass were exposed for 48 and 96 h to an Arabian light crude oil and their responses were assessed at the molecular and physiological levels. The aim of the study was therefore to assess (i) the short term effects of crude oil exposure by the measurement of several molecular biomarkers, (ii) the consequences of this short term exposure on fish health by using growth and condition indices measured after a decontamination period of 28 and 26 d in seawater. Hydrocarbon petroleum concentrations was monitored during the 96 h experiments and an increase of PAH concentrations were found in fish following both exposure times. An 7-ethoxyresorufin-O-deethylase (EROD) induction was observed after 48 h of exposure, while a significant decrease in the sea bass specific growth rate in length and for the RNA:DNA ratio was observed 28 d after that exposure ceased. The EROD induction doubled after the 96 h exposure, and a significant increase in GST activities was observed. A significant decrease in the specific growth rates, the otolith recent growth, the RNA:DNA ratio and the Fulton's K condition index were then observed in sea bass 26 d after the 96 h exposure to mechanically dispersed crude oil compared to the control. The present study shows that growth and condition indices can prove useful in assessing fish health status following an oil spill. Their complementary analysis with sensitive molecular biomarkers as EROD could improve the determination of oil spill impact on fish populations.


Assuntos
Bass/fisiologia , Petróleo/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Monitoramento Ambiental , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Glutationa Transferase/metabolismo , Petróleo/análise , Poluição por Petróleo , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Água do Mar/química , Estresse Fisiológico , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-17553717

RESUMO

Lipids play a key role in thermal and photo-acclimation processes, yet they are often neglected in stress studies. We investigated the influence of different light intensities and an increase of temperature on the fatty acid composition of the coral Montipora digitata and its symbiotic algae (i.e., zooxanthellae). Coral branches were subjected to 3 different light intensities (7, 30 and 95% sea surface photosynthetic active radiation) in filtered seawater for 35 days. Fatty acids as methyl esters were determined using gas chromatography (GC) and verified by GC-mass spectrometry. Different light intensities, but only in combination with increased temperature, significantly affected the fatty acid composition of the coral host and zooxanthellae. Temperature and light intensity increases caused reductions in the proportion of polyunsaturated fatty acids in both the host and symbionts. Most changes occurred in the host coral, which suggests that the host is more susceptible to environmental change than the symbiont, or that the host shields the symbionts from environmental change.


Assuntos
Aclimatação/fisiologia , Antozoários/química , Antozoários/fisiologia , Dinoflagellida/química , Ácidos Graxos/análise , Animais , Eucariotos/química , Luz , Densidade Demográfica , Reprodução , Simbiose/fisiologia , Temperatura
7.
Arch Mal Coeur Vaiss ; 99(2): 95-101, 2006 Feb.
Artigo em Francês | MEDLINE | ID: mdl-16555691

RESUMO

BACKGROUND: informed consent is a fundamental and legal obligation for each interventional cardiologist. The effect of consent form describing risks of invasive procedure on anxiety is controversial. This trial was aimed to assess the added value of video information to the standard informed consent process. METHODS: 200 consecutive patients undergoing coronary angiography were enrolled. The first one hundred were assigned to conventional education conducted by the physician (no video group) and the second one hundred had consent obtained in the conventional manner assisted by video information (video group). The outcome variables for this comparison consisted of a standard anxiety score (Spielberger Statement Anxiety Inventory questionnary) plus hemodynamics measurements of heart rate, systolic and diastolic blood pressure obtained at baseline and immediately after written informed consent In addition, before discharge, patients graded the tolerability and satisfaction on a 4-point scale. RESULTS: The groups were similar with regard to their baseline characteristics and anxity score (37+23 vs 37+23). Patients who had not had prior experience of catheterization had higher baseline anxiety than those who had prior angiography (45 + 22 vs 31 + 20; p = 0.027). Patients who watched the video were significantly less anxious after informed consent (28 + 21 vs 34 + 22; p = 0.048) and had a significantly lower heart rate (65 + 10 vs 71 + 12; p = 0.03). The benefits of video information were especially prominent in those with higher anxiety scores at baseline (score after 45 + 24 vs 57 + 26; p = 0.046). Tolerability were higher in the video group compared with no video group (98% vs 86%; p = 0.003). Finally, satisfaction of information for informed consent process was higher in video group than in no video group (99% vs 76%; p = 0.001). CONCLUSION: a video information decreased anxiety level after written informed consent and improved tolerability and satisfaction scales in patients undergoing coronary angiography. The most likely to benefit from video information are patients with higher anxiety level at baseline. Beneficial effect on informed refusal should be investigated in larger population.


Assuntos
Angiografia Coronária/psicologia , Educação de Pacientes como Assunto/métodos , Gravação de Videoteipe , Adaptação Psicológica , Idoso , Ansiedade , Feminino , França , Humanos , Consentimento Livre e Esclarecido , Masculino , Satisfação do Paciente
8.
Ann Cardiol Angeiol (Paris) ; 54(4): 201-11, 2005 Aug.
Artigo em Francês | MEDLINE | ID: mdl-16104621

RESUMO

Drug eluting stents have been developed in order to reduce in-stent restenosis observed with a 20 to 40% rate in bare-stents. Neoinitimal smooth muscular cells proliferation have been characterized as the corner stone of in-stent restenosis. Consequently, many anti-mitotic and anti-inflammatory drugs have been evaluated in a new stent generation, so called coated stents or drug eluting stents. Three major components must be considered to evaluate the beneficial effects: the bare-stent, the drug, and the deliverance system, most usually a polymer. For the present, sirolimus eluting stent and paclitaxel eluting stent are available in the market with the european conformity label considering evidence based medicine established in randomized trials. Both stents have been shown to reduce in-stent restenosis incidence to less than 7%. Long-term follow-up still remain expected and would give answers to two safety queries: what is about the incidence of late stent thrombosis, what is about mal-apposition consequences in clinical feature. Utilization of drug eluting stent in clinical practice must considered materials with european conformity and must applied French society of cardiology guidelines restricting implantation to patients who meet high-risk restenosis criteria. Medicoeconomic approach must be considered beneficial at the present only in patients with high restenosis risk. Long-term antiplatelet regimen of aspirin and clopidogrel must be considered to avoid late stent thrombosis.


Assuntos
Reestenose Coronária/prevenção & controle , Sistemas de Liberação de Medicamentos , Imunossupressores/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Stents , Ensaios Clínicos como Assunto , Humanos , Paclitaxel/uso terapêutico , Sirolimo/uso terapêutico , Stents/economia , Tacrolimo/uso terapêutico , ortoaminobenzoatos/uso terapêutico
9.
Arch Mal Coeur Vaiss ; 97(4): 291-8, 2004 Apr.
Artigo em Francês | MEDLINE | ID: mdl-15182071

RESUMO

AIM: As compared to the femoral approach, the use of radial arterial access has been demonstrated to reduce the incidence of access site bleeding complications in staged procedures. The purpose of this study was to evaluate clinical outcomes comparing radial and femoral approaches in the treatment of acute myocardial infarction with emergency angioplasty. METHODS: Between September 1999 and December 2002, we prospectively enrolled 162 consecutive patients undergoing primary angioplasty with abciximab (n=127) or rescue angioplasty after thrombolysis failure (n=35) comparing in a non-randomized plan radial (n=87) and femoral (n=75) access. RESULTS: Cannulation time (from patient arrival at the catheterization laboratory to the effective placement of arterial sheath) and procedural time was not significantly different in radial and femoral groups (respectively 8.5 +/- 5.2 vs 9.0 +/- 5.8 minutes, p=0.81, and 42 +/- 28 vs 44 +/- 27 min, p=0.74). Nevertheless, time of radiation (23.1 +/- 11 min vs 16.5 +/- 10.9 min; p=0.01) and dose-area product (229 +/- 133 vs 151 +/- 86 Gy.cm2, p=0.01) were significantly higher in the radial group. Angiographic success rate is comparable in both groups. Freedom from ischemic recurrent events at 1-month follow-up occurred in 84 (96%) and 69 (92%) patients in the radial and femoral groups, respectively (p=0.12). There were no major access site bleeding complications in the radial group, as opposed to six (8%) in the femoral group (p=0.01) all requiring transfusions and surgical repair necessary in four. Uncomplicated clinical course occurred in 83 (92%) of patients in the radial group and 65 (85%) in the femoral group (p=0.03). Total hospital length of stay was significantly higher in the femoral group (5.9 +/- 2.1 days vs 3.5 +/- 1.2 days; p=0.009). CONCLUSION: In patients with acute myocardial infarction treated with coronary angioplasty, the transradial access is efficacious with fewer major access site complications than transfemoral access. Transradial approach produces a shorter length of stay, as compared to the transfemoral approach although with longer times of radiation and higher dose area-product.


Assuntos
Angioplastia Coronária com Balão/métodos , Infarto do Miocárdio/terapia , Cateterismo Periférico , Angiografia Coronária , Feminino , Artéria Femoral , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Artéria Radial , Resultado do Tratamento
10.
Artigo em Inglês | MEDLINE | ID: mdl-12831773

RESUMO

We compared the fatty acid composition of the host-coral Montipora digitata with the fatty acid composition in the coral's endosymbiotic dinoflagellates (zooxanthellae). Fatty acids as methyl esters were determined using gas chromatography (GC) and verified by GC-mass spectrometry. We found the main difference between the fatty acids in the host and their symbionts were that zooxanthellae supported higher proportions of polyunsaturated fatty acids. The presence of fatty acids specific to dinoflagellates (i.e. 18:4omega3, 22:5omega3 and 22:6omega3) in the host tissue suggests that zooxanthellae provide the coral host not only with saturated fatty acids, but also with diverse polyunsaturated fatty acids.


Assuntos
Antozoários/metabolismo , Dinoflagellida/metabolismo , Ácidos Graxos Insaturados/metabolismo , Simbiose , Animais , Antozoários/microbiologia , Composição Corporal , Dieta
11.
Arch Mal Coeur Vaiss ; 96(3): 175-80, 2003 Mar.
Artigo em Francês | MEDLINE | ID: mdl-12722546

RESUMO

Between September 1999 and June 2001, 591 patients required ad hoc coronary angioplasty. The authors compared the group of patients in whom the approach of first intent was radial (n = 328, 55%) with those in whom the femoral approach had been used (n = 263), in terms of immediate local (haematoma or thrombosis requiring surgical intervention or transfusion) and general complications (myocardial infarction, cerebrovascular accident), and major adverse cardiovascular events (infarction, angioplasty, bypass and death) at 1 year. The dose of ionising radiation during the procedures was also compared prospectively. The conversion rate from the radial (R) to the humeral or femoral (F) approach was 10%. The angioplasty, stenting, and stenting without dilatation failure rates were identical in the two groups (5% versus 5%, 0.6% versus 1.9%, 3% versus 4%, respectively). The average irradiation time was greater in the R group than in the F group (23 +/- 12 min vs 17 +/- 4 min, p < 0.001) as was the irradiation per surface unit (242 +/- 137 Gy.cm2 vs 185 +/- 117 Gy.cm2, p < 0.001). The immediate complication rate was comparable in the two groups (2.5% in group R vs 3.6% in group F) as was the major adverse cardiovascular event rate at 1 year (13% in both groups). The authors observed the same rate of immediate complications and late adverse cardiac events in patients undergoing coronary angioplasty followed by immediate angioplasty by the radial or femoral approaches with an acceptable conversion rate from the radial to the femoral approach. The procedures by the radial approach seem to be associated with a greater time and dosage of ionising radiation.


Assuntos
Angioplastia Coronária com Balão/métodos , Doença das Coronárias/terapia , Artéria Femoral , Artéria Radial , Idoso , Cateterismo Cardíaco/métodos , Humanos , Modelos Lineares , Estudos Prospectivos , Dosagem Radioterapêutica , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
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