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Registros recuperados: 95 | |
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Rabalais,Nancy N. |
The seasonal formation of a bottom-water layer severely depleted in dissolved oxygen has become a perennial occurrence on the Louisiana continental shelf adjacent to the Mississippi River system. Dramatic changes have occurred in this coastal ecosystem in the last half of the 20th century as the loads of dissolved inorganic nitrogen tripled. There are increases in primary production, shifts in phytoplankton community composition, changes in trophic interactions, and worsening severity of hypoxia. The river-influenced continental shelf is representative of similar ecosystems in which increased nutrient flux to the coastal ocean has resulted in eutrophication and subsequently hypoxia. The hypoxic conditions (dissolved oxygen less than 2 mg L-1) cover up to... |
Tipo: Journal article |
Palavras-chave: Anoxia; Hypoxia; Eutrophication; Nutrients; Nitrogen. |
Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-65382006000300015 |
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Souza,Samara Silva de; Silva,Grazyelle Sebrenski da; Almeida-Val,Vera Maria Fonseca de. |
Abstract The present study aimed to evaluate the biological responses of Colossoma macropomum to naphthalene injection and subsequent hypoxia exposure, emphasizing the expression of the tumor suppressor gene tp53. Tambaquis were intraperitoneally injected with naphthalene (50 mg/kg) and, after 96 hours, the fish were transferred to respirometry chambers and, submitted to progressive hypoxia for the determination of critical PO2. In a subsequent experiment, the fish received an intraperitoneal injection of naphthalene and were kept for 96 hours under normoxia. Successively, fish were challenged with acute hypoxia (PO2<PO2 crit) during 6 hours. We observed that the PO2 crit was not affected by naphthalene injection. Moreover, hematological parameters were... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Naphthalene; Hypoxia; Tumor suppressor gene tp53; DNA damage; Tambaqui. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572019000300411 |
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Almeida-Val,Vera Maria Fonseca; Oliveira,Alice Reis; Silva,Maria de Nazaré Paula da; Ferreira-Nozawa,Monica Stropa; Araújo,Roziete Mendes; Val,Adalberto Luis; Nozawa,Sérgio Ricardo. |
Adaptation or acclimation to hypoxia occurs via the modulation of physiologically relevant genes, such as erythropoietin, transferrin, vascular endothelial growth factor, phosphofructokinase and lactate dehydrogenase A. In the present study, we have cloned, sequenced and examined the modulation of the LDH-A gene after an Amazonian fish species, Astronotus crassipinis (the Oscar), was exposed to hypoxia and anoxia. In earlier studies, we have discovered that adults of this species are extremely tolerant to hypoxia and anoxia, while the juveniles are less tolerant. Exposure of juveniles to acute hypoxia and anoxia resulted in increased LDH-A gene expression in skeletal and cardiac muscles. When exposed to graded hypoxia juveniles show decreased LDH-A... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Amazon; Fishes; Gene expression; RT-PCR; LDH-A; Hypoxia; Anoxia. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000200025 |
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Guevelou, Eric; Huvet, Arnaud; Sussarellu, Rossana; Milan, Massimo; Guo, Xinmei; Li, Li; Zhang, Guofan; Quillien, Virgile; Daniel, Jean-yves; Quere, Claudie; Boudry, Pierre; Corporeau, Charlotte. |
AMP-activated protein kinase α (AMPKα) is a key regulator of energy balance in many model species during hypoxia. In a marine bivalve, the Pacific oyster Crassostrea gigas, we analyzed the protein content of adductor muscle in response to hypoxia during 6 h. In both smooth and striated muscles, the amount of full-length AMP-activated protein kinase α (AMPKα) remained unchanged during hypoxia. However, hypoxia induced a rapid and muscle-specific response concerning truncated isoforms of AMPKα. In the smooth muscle, a truncated isoform of AMPKα was increased from 1 to 6 h of hypoxia, and was linked with accumulation of AKT kinase, a key enzyme of the insulin signaling pathway which controls intracellular glucose metabolism. In this muscle, aerobic metabolism... |
Tipo: Text |
Palavras-chave: Marine bivalve; Crassostrea gigas; Hypoxia; AMP-activated protein kinase; Alternative splicing; Adductor muscle. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00119/22998/21397.pdf |
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Mazurais, David; Ferraresso, Serena; Gatta, Pier Paolo; Desbruyeres, Elisabeth; Severe, Armelle; Corporeau, Charlotte; Claireaux, Guy; Bargelloni, Luca; Zambonino, Jose-luis. |
Coastal systems could be affected by hypoxic events brought about by global change. These areas are essential nursery habitats for several fish species including the common sole (Solea solea L.). Tolerance of fish to hypoxia depends on species and also on their physiological condition and nutritional status. Indeed, high dietary lipid content has been recently shown to negatively impact the resistance of sole to a severe hypoxic challenge. In order to study the molecular mechanisms involved in the early response to hypoxic stress, the present work examined the hepatic transcriptome in common sole fed diets with low and high lipid content, exposed to severe hypoxia. The activity of AMP-activated protein kinase (AMPK) was also investigated through the... |
Tipo: Text |
Palavras-chave: Fish; Hypoxia; Nutrition; Liver; Transcriptome; AMPK. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00169/28062/26474.pdf |
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Claireaux, Guy; Theron, Michael; Prineau, Michel; Dussauze, Matthieu; Merlin, Francois Xavier; Le Floch, Stephane. |
The worldwide increasing recourse to chemical dispersants to deal with oil spills in marine coastal ecosystems is a controversial issue. Yet, there exists no adequate methodology that can provide reliable predictions of how oil and dispersant-treated oil can affect relevant organism or population-level performance. The primary objective of the present study was to examine and compare the effects of exposure to untreated oil (weathered Arabian light crude oil), chemically dispersed oil (Finasol, TOTAL-Fluides) or dispersant alone, upon the ability of fish for environmental adaptation. To reach that goal, we implemented high-throughput, non-lethal challenge tests to estimate individual hypoxia and heat tolerance as surrogate measures of their capacity to... |
Tipo: Text |
Palavras-chave: Oil-spill; Dispersant; Fish; Temperature; Hypoxia; Survival; Growth; Environmental adaptation ability; Darwinian fitness. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00137/24831/23045.pdf |
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Zambonino, Jose-luis; Claireaux, Guy; Ernande, Bruno; Quazuguel, Patrick; Severe, Armelle; Huelvan, Christine; Mazurais, David. |
An individual's environmental history may have delayed effects on its physiology and life history at later stages in life because of irreversible plastic responses of early ontogenesis to environmental conditions. We chose a marine fish, the common sole, as a model species to study these effects, because it inhabits shallow marine areas highly exposed to environmental changes. We tested whether temperature and trophic conditions experienced during the larval stage had delayed effects on life-history traits and resistance to hypoxia at the juvenile stage. We thus examined the combined effect of global warming and hypoxia in coastal waters, which are potential stressors to many estuarine and coastal marine fishes. Elevated temperature and better trophic... |
Tipo: Text |
Palavras-chave: Fish; Environmental programming; Climate change; Hypoxia; Nutrition. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00127/23858/21810.pdf |
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Legovic, T; Justic, D. |
Eutrophication of the northern Adriatic Sea was investigated using data on dissolved oxygen (DO) from 1911 to 1982. Beginning in the period 1955-1965, DO concentrations increased in the surface layer and decreased close to the bottom in all seasons except winter. These changes are attributed to an increase of the anthropogenic nutrient inflow. The occurrence of hypoxia near the bottom and its disappearance were investigated using the vertical distribution of DO on the transect from the Po delta to Rovinj during 1973. Horizontal distributions of DO close to the surface and near the bottom show prominent gradients from the Po delta towards the middle of the northern Adriatic Sea. Application of a simple box model indicates that phytoplankton blooms which... |
Tipo: Text |
Palavras-chave: Hypoxia; Phytoplankton blooms; Nutrients; Eutrophication; Adriatic Sea. |
Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00093/20451/18123.pdf |
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Cadiz, Laura; Zambonino-infante, Jose-luis; Quazuguel, Patrick; Madec, Lauriane; Le Delliou, Herve; Mazurais, David. |
Several physiological functions in fish are shaped by environmental stimuli received during early life. In particular, early-life hypoxia has been reported to have long-lasting effects on fish metabolism, with potential consequences for fish life history traits. In the present study, we examine whether the synergistic stressors hypoxia (40% and 100% air saturation) and temperature (15° and 20 °C), encountered during early life, could condition later metabolic response in European sea bass (Dicentrarchus labrax) juveniles. Growth rate and metabolic parameters related to carbohydrate and lipid metabolism in the liver were investigated at the juvenile stage under normoxic and chronic hypoxic conditions. Juvenile growth rates were significantly lower... |
Tipo: Text |
Palavras-chave: Hypoxia; Developmental plasticity; Metabolism; European sea bass. |
Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00404/51536/52126.pdf |
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Pichavant, Karine; Person, Jeannine; Le Bayon, Nicolas; Severe, Armelle; Le Roux, Annick; Boeuf, Gilles. |
When juvenile turbot Scophthulmus maximus and sea bass Dicentrarchus labrax were fed to satiation, growth and food intake were depressed under hypoxia (3.2 +/- 0.3 and 4.5 +/- 0.2 mg O-2 l(-1)). However, no significant difference in growth was observed between fishes maintained in hypoxia and fed to satiation and fishes reared in normoxia (7.4 +/- 0.3 mg O-2 l(-1)) and fed restricted rations (same food intake of fishes at 3.2 mg O-2 l(-1)). Routine oxygen consumption of fishes fed to satiation was higher in normoxia than in hypoxia due to the decrease in food intake in the latter. Of the physiological parameters measured, no significant changes were observed in the two species maintained in hypoxia. This study confirms the significant interaction between... |
Tipo: Text |
Palavras-chave: Oxygen consumption; Growth; Hypoxia; Sea bass; Turbot. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-617.pdf |
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Bardon-albaret, Agnes; Saillant, Eric. |
The effects of hypoxic conditions and elevated ammonia concentrations on the viability of embryos and newly hatched larvae of the red snapper (Lutjanus campechanus) were investigated. In all experiments, tested levels of hypoxia or ammonia concentrations were applied to embryos and unfed newly hatched larvae from three different spawns. Exposures began at 1 h post fertilization (pf) and lasted until all individuals in a group had expired. Survival rates were monitored daily in duplicates for each spawn in each treatment. Fertilized eggs exposed to 2 mg L− 1 dissolved oxygen (29% saturation) showed complete mortality before hatch while 81% of embryos in control groups (> 85% saturation) hatched and subsequently maintained high survival until 5 days pf.... |
Tipo: Text |
Palavras-chave: Lutjanus campechanus; Hypoxia; Ammonia; Egg quality; Stress; Water quality. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00321/43188/42735.pdf |
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Ory, Pascaline; Bonnet, Antoine; Mondeguer, Florence; Breitwieser, Marine; Dubillot, Emmanuel; Graber, Marianne. |
Mimachlamys varia is a sub-littoral bivalve encountered from Norway to the Mediterranean Sea, which lives mostly byssally attached to rocks. During the low tide period, M. varia individuals, located highest on the shore, may experience short time of aerial exposure and face a low availability of oxygen. Here we report a comparative metabolomic profiling of gill samples of M. varia obtained by both LC-QToF and APGC-QToF mass spectrometry, to analyze metabolic changes occurring during emersion in comparison with immersion. Scallops were grown in aquaria with a simulated intertidal environment mimicking short-duration air exposure that they might experience during extreme tides: alternating 2 h emersion and 10 h immersion. Our results show a switch from... |
Tipo: Text |
Palavras-chave: Anaerobic; APGC-QToF mass spectrometry; Hypoxia; Intertidal; LC-QToF mass spectrometry; Metabolomics; Mimachlamys varia; PLS-DA. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00466/57741/59936.pdf |
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Registros recuperados: 95 | |
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