Consulta: subjectFacets:"ATP"
Registros recuperados: 15
Data/hora: 01/06/2024 01:21:31

Caracteristiques saisonnieres de l'hydrobiologie du complexe estuariende Marennes-Oleron (France).
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Heral, Maurice; Razet, Daniel; Deslous-paoli, Jean-marc; Berthome, Jean-paul; Garnier, J.
Four seasonal compaigns providing a sampling of 15 stations each followed during half a tide cycle, i.e. 120 water samples permit the definition of the main hydrobiological features of Marennes-Oleron Bay: salinity and turbidity, phytoplanktonic biomasses, ATP concentrations. The authors suggest that a new way of adapted sampling to their objectives, will work out in the future by sampling during tidal cycles but as frequently as possible.
Tipo: Text
Palavras-chave: Seasonal variations; Salinity; ATP; Estuaries; Turbidity; Hydrobiology; Salinity; Phytoplankton; Estuaries; Biomass; Hydrobiology; Physicochemical properties; Phytoplankton; Environmental conditions; Biomass.
Ano: 1982
URL: http://archimer.ifremer.fr/doc/1982/publication-1854.pdf

Preliminary results from POLMAR III (April 13-18, 1978) (SUROIT III) ATP, primary production and respiration rates in zooplankton. Complément à la Communication du Groupe Ecophysiologie du Centre Océanologique de Bretagne (SAMAIN et al.)
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Hendrikson, P.; Hirche, H.j.; Junghans,, U.
ATP, primary production and respiration rates in seston, respiration rates in zooplankton have been investigated after the spill by "AMOCO CADIZ". Gross primary production seems to be similar to the normal situation. The rate of photosynthesis is lower at the "AMOCO CADIZ" station than at any of the others. Respiration rates are surprisingly high at the surface. ATP concentra­tion exhibit an homogeneous pattern, zooplankton respiration are similar to the data obtained in Peruvian upwelled waters or in zooplankton culture. A more detailed computation of data will be necessary before concluding.
Tipo: Text
Palavras-chave: Plancton; Taux respiratoires; ATP; Production primaire; Pollution; AMOCO CADIZ; Plankton; Respiration rates; ATP; Primary production; Pollution; AMOCO CADIZ.
Ano: 1978
URL: http://archimer.ifremer.fr/doc/00306/41729/40940.pdf

Réponses et adaptations de la charge énergétique adénylique et l'activité enzymatique digestive à l'emersion chez Crassostrea gigas
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Moal, Jeanne; Samain, Jean-francois.
The effect of tidal emergence on the adenylate energy charge value was studied in Crassostrea gigas oysters in Marennes-Oleron Bay. The shot-term AEC responses to aerial exposure differed according to the period of the year. However, on a long-term basis, osters from three bathymetric positions exhibited the same AEC value, but had a different growth rate. The amylase increase observed for the most emerged oysters may play a role in the maintenance of energy equilibrium.
Tipo: Text
Palavras-chave: Charge énergétique; Amylase; Emersion; Huîtres; Crassostrea gigas; Cycle de marée; ATP; Adenylic energy charge; Amylase; Emersion; Oysters; Crassostrea gigas; Tidal cycle.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/00022/13285/10331.pdf

Ecophysiological and metabolic adaptations to sulphide exposure of the oyster Crassostrea gigas
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Le Moullac, Gilles; Cheize, Marie; Gastineau, Olivier; Daniel, Jean-yves; Le Coz, Jean-rene; Huvet, Arnaud; Moal, Jeanne; Pouvreau, Stephane; Van Wormhoudt, A; Samain, Jean-francois.
The purpose of this study is to examine the response of the oyster Crassostrea gigas to sulphide at different biological scales. A first experiment was designed to measure for 20 h the clearance (CR) and oxygen consumption (OC) rates of oysters exposed at different concentrations of sulphide (0, 3, 6, 12, 20, and 40 mu M). The second experiment was carried out to evaluate the metabolic adaptations to chronic sulphide exposure for 10 days by measuring PK and PEPCK enzyme activities, succinate and alanine content, the adenylate energy charge (AEC), and the activity of the electron transport system (ETS)in whole oysters at above 20 mu M. PK and PEPCK mRNAs and enzyme activities have been measured in adductor muscle. When exposed to sulphide above 20 mu M, CR...
Tipo: Text
Palavras-chave: ATP; AEC; Electron transport system; Succcinate; Alanine; Phosphoenolpyruvate carboxykinase; Pyruvate kinase; Oxygen consumption; Clearance rate; Crassostrea gigas; Sulphide; Oyster.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-3924.pdf

Effect of Bentazon on Growth and Physiological Responses of Marine Diatom: Chaetoceros gracilis
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Hourmant, Annick; Amara, Anis; Pouline, Patrick; Durand, Gael; Arzul, Genevieve; Quiniou, Francoise.
The herbicide bentazon (CASRN 25057-89-0) is extensively used in agriculture in Brittany (France) to replace atrazine. Bentazon is not readily adsorbed by soil and therefore it enters adjacent freshwater ecosystems, making its way to estuarine and marine waters areas. Information regarding its effects on marine ecosystems is scarce. Phytotoxicity assessments were conducted in the laboratory on the common diatom Chaetoceros gracilis using both the active ingredient and its formulated product (Basamais). The 3 day EC50 Using cell counts were, respectively, 150 mg/L and 60 mu g/L for bentazon active ingredient and for bentazon-formulated while cellular volume was increased. Although bentazon is known as a photosystem II inhibitor, it produced an increase of...
Tipo: Text
Palavras-chave: Photosynthesis; Marine diatom; Growth; Chlorophylls; Chaetoceros gracilis; Carotenoids; Bentazon; ATP.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6637.pdf

Assessment of oocyte and trochophore quality in Pacific oyster, Crassostrea gigas
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Boulais, Myrina; Corporeau, Charlotte; Huvet, Arnaud; Bernard, Ismael; Quere, Claudie; Quillien, Virgile; Fabioux, Caroline; Suquet, Marc.
Pacific oyster hatchery production remains highly variable, partially due to inconsistent gamete quality. However, little attention has been paid to oocyte quality in Pacific oyster compared to important vertebrate aquaculture species such as fishes. The aims of the present study were to identify criteria of oocyte and trochophore quality used as predictive tools for embryo developmental success at the D-larval stage. Twenty-six potential proxies of oocyte and trochophore quality were studied on 25 mature females, as determined using histology. Some morphological and biochemical characteristics of mature oocytes were described. Protein appeared to be the main constituent of fully mature Pacific oyster oocytes. Neutral lipids accounted for 61% of the total...
Tipo: Text
Palavras-chave: Crassostrea gigas; Oocyte quality; Trochophore; Lipid; Gene expression; ATP.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00239/35010/33544.pdf

Changes in motility, ATP content, morphology and fertilisation capacity during the movement phase of tetraploid Pacific oyster (Crassostrea gigas) sperm
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Suquet, Marc; Labbe, C.; Brizard, Raphael; Donval, Anne; Le Coz, Jean-rene; Quere, Claudie; Haffray, P.
Changes in sperm features during the movement phase are especially interesting to study in external fertilization species whose sperm duration movement is long because this implies a significant adaptation of moving cells to the external medium. This study describes the changes in tetraploid Pacific oyster sperm characteristics in relation to time post activation. Sperm individually collected on three tetraploid males were activated in seawater. Their features were analysed over a 24 h period and compared to a sperm pool collected on three diploid males as a reference. The percentage of motile spermatozoa, the intracellular ATP content, and the fine structure of spermatozoa were studied in relation to time post activation. Furthermore, the fertilisation...
Tipo: Text
Palavras-chave: Crassostrea gigas; Sperm; Tetraploid; Motility; ATP; Ultrastructure.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00006/11756/8639.pdf

NTPDase and acetylcholinesterase activities in silver catfish, Rhamdia quelen (Quoy &amp;amp; Gaimard, 1824) (Heptapteridae) exposed to interaction of oxygen and ammonia levels
Provedor de dados: Neotropical Ichthyology
Autores: Kaizer,Rosilene Rodrigues; Loro,Vania Lúcia; Schetinger,Maria Rosa Chitolina; Morsch,Vera Maria; Tabaldi,Luciane Almeri; Rosa,Cíntia Saydelles da; Garcia,Luciano de Oliveira; Becker,Alexssandro G.; Baldisserotto,Bernardo.
The effects of various levels of oxygen saturation and ammonia concentration on NTPDase (ecto-nucleoside triphosphate diphosphohydrolase, E.C. 3.6.1.5) and acetylcholinesterase (AChE, E.C. 3.1.1.7) activities in whole brain of teleost fish (Rhamdia quelen) were investigated. The fish were exposed to one of two different dissolved oxygen levels, including high oxygen (6.5 mg.L-1) or low oxygen (3.5 mg.L-1), and one of two different ammonia levels, including high ammonia (0.1 mg.L-1) or low ammonia (0.03 mg.L-1) levels. The four experimental groups included the following (A) control, or high dissolved oxygen plus low NH3; (B) low dissolved oxygen plus low NH3; (C) high dissolved oxygen plus high NH3; (D) low dissolved oxygen plus high NH3. We found that...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fish; ATP; ADP; AChE.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252009000400012

Extracellular ATP in the lymphohematopoietic system: P2Z purinoceptors and membrane permeabilization
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Persechini,P.M.; Bisaggio,R.C.; Alves-Neto,J.L.; Coutinho-Silva,R.
The effects of extracellular nucleosides and nucleotides on many organs and systems have been recognized for almost 50 years. The effects of extracellular ATP (ATPo), UTPo, ADPo, and other agonists are mediated by P2 purinoceptors. One of the most dramatic effects of ATPo is the permeabilization of plasma membranes to low molecular mass solutes of up to 900 Da. This effect is evident in several cells of the lymphohematopoietic system and is supposed to be mediated by P2Z, an ATP4--activated purinoceptor. Here, we review some basic information concerning P2 purinoceptors and focus our attention on P2Z-associated phenomena displayed by macrophages. Using fluorescent dye uptake, measurement of free intracellular Ca2+ concentration and electrophysiological...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: ATP; P2Z purinoceptor; Macrophage; Monocyte; T cell; Permeabilization.
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1998000100004

Effects of eugenol on resting tension of rat atria
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Olivoto,R.R.; Damiani,C.E.N.; Kassouf Silva,I.; Lofrano-Alves,M.S.; Oliveira,M.A.; Fogaça,R.T.H.
In cardiac and skeletal muscle, eugenol (μM range) blocks excitation-contraction coupling. In skeletal muscle, however, larger doses of eugenol (mM range) induce calcium release from the sarcoplasmic reticulum. The effects of eugenol are therefore dependent on its concentration. In this study, we evaluated the effects of eugenol on the contractility of isolated, quiescent atrial trabeculae from male Wistar rats (250-300 g; n=131) and measured atrial ATP content. Eugenol (1, 3, 5, 7, and 10 mM) increased resting tension in a dose-dependent manner. Ryanodine [100 µM; a specific ryanodine receptor (RyR) blocker] and procaine (30 mM; a nonspecific RyR blocker) did not block the increased resting tension induced by eugenol regardless of whether extracellular...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Eugenol; Atrial trabeculae; Resting tension; Ryanodine; Rat; ATP.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2014000400328

Cl- and regulation of pH by MDCK-C11 cells
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Tararthuch,A.L.; Fernandez,R.; Malnic,G.
The interaction between H+ extrusion via H+-ATPase and Cl- conductance was studied in the C11 clone of MDCK cells, akin to the intercalated cells of the collecting duct. Cell pH (pHi) was measured by fluorescence microscopy using the fluorescein-derived probe BCECF-AM. Control recovery rate measured after a 20 mM NH4Cl acid pulse was 0.136 ± 0.008 pH units/min (dpHi/dt) in Na+ Ringer and 0.032 ± 0.003 in the absence of Na+ (0 Na+). With 0 Na+ plus the Cl- channel inhibitor NPPB (10 µM), recovery was reduced to 0.014 ± 0.001 dpHi/dt. 8-Br-cAMP, known to activate CFTR Cl- channels, increased dpHi/dt in 0 Na+ to 0.061 ± 0.009 and also in the presence of 46 nM concanamycin and 50 µM Schering 28080. Since it is thought that the Cl- dependence of H+-ATPase might...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cell pH; CAMP; ATP; H+-ATPase; Valinomycin; Cl-.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2007000500012

Purine nucleotides reduce superoxide production by nitric oxide synthase in a murine sepsis model
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Barbeiro,H.V.; Barbeiro,D.F.; Debbas,V.; Souza,H.P.; Laurindo,F.R.; Velasco,I.T.; Soriano,F.G.
Sepsis involves a systemic inflammatory response of multiple endogenous mediators, resulting in many of the injurious and sometimes fatal physiological symptoms of the disease. This systemic activation leads to a compromised vascular response and endothelial dysfunction. Purine nucleotides interact with purinoceptors and initiate a variety of physiological processes that play an important role in maintaining cardiovascular function. The purpose of the present study was to investigate the effects of ATP on vascular function in a lipopolysaccharide (LPS) model of sepsis. LPS induced a significant increase in aortic superoxide production 16 h after injection. Addition of ATP to the organ bath incubation solution reduced superoxide production by the aortas of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: ATP; Endotoxin; Endothelium; Superoxide; Nitric oxide.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009001100009

Nitric oxide modulates ATP-evoked currents in mouse Leydig cells
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: de Deus,J.L.; Dagostin,A.L.A.; Varanda,W.A.
Testosterone synthesis within Leydig cells is a calcium-dependent process. Intracellular calcium levels are regulated by different processes including ATP-activated P2X purinergic receptors, T-type Ca2+ channels modulated by the luteinizing hormone, and intracellular calcium storages recruited by a calcium-induced calcium release mechanism. On the other hand, nitric oxide (NO) is reported to have an inhibitory role in testosterone production. Based on these observations, we investigated the interaction between the purinergic and nitrergic systems in Leydig cells of adult mice. For this purpose, we recorded ATP-evoked currents in isolated Leydig cells using the whole cell patch clamp technique after treatment with L-NAME (300 μM and 1 mM), L-arginine (10,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Leydig cells; ATP; Purinergic receptor; Calcium; Nitric oxide; Whole cell patch clamp.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2018000500603

Proteoliposomes as matrix vesicles' biomimetics to study the initiation of skeletal mineralization
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Simão,A.M.S.; Yadav,M.C.; Ciancaglini,P.; Millán,J.L.
During the process of endochondral bone formation, chondrocytes and osteoblasts mineralize their extracellular matrix by promoting the formation of hydroxyapatite (HA) seed crystals in the sheltered interior of membrane-limited matrix vesicles (MVs). Ion transporters control the availability of phosphate and calcium needed for HA deposition. The lipidic microenvironment in which MV-associated enzymes and transporters function plays a crucial physiological role and must be taken into account when attempting to elucidate their interplay during the initiation of biomineralization. In this short mini-review, we discuss the potential use of proteoliposome systems as chondrocyte- and osteoblast-derived MVs biomimetics, as a means of reconstituting a phospholipid...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Alkaline phosphatase; Biomineralization; Calcification; Lipids; Pyrophosphate; ATP.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2010000300003

P-glycoprotein-mediated resistance to chemotherapy in cancer cells: using recombinant cytosolic domains to establish structure-function relationships
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Di Pietro,A.; Dayan,G.; Conseil,G.; Steinfels,E.; Krell,T.; Trompier,D.; Baubichon-Cortay,H.; Jault,J.-M.
Resistance to chemotherapy in cancer cells is mainly mediated by overexpression of P-glycoprotein (Pgp), a plasma membrane ATP-binding cassette (ABC) transporter which extrudes cytotoxic drugs at the expense of ATP hydrolysis. Pgp consists of two homologous halves each containing a transmembrane domain and a cytosolic nucleotide-binding domain (NBD) which contains two consensus Walker motifs, A and B, involved in ATP binding and hydrolysis. The protein also contains an S signature characteristic of ABC transporters. The molecular mechanism of Pgp-mediated drug transport is not known. Since the transporter has an extraordinarily broad substrate specificity, its cellular function has been described as a "hydrophobic vacuum cleaner". The limited knowledge...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: P-glycoprotein (Pgp); Multidrug resistance; Anticancer chemotherapy; ATP; Steroids; Flavonoids.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000800001