Consulta: subjectFacets:"Redox"
Registros recuperados: 7
Data/hora: 03/06/2024 16:44:57

The crustacean selenoproteome similarity to other arthropods homologs: A mini review
Provedor de dados: 69
Autores: García-Triana,Antonio; Yepiz-Plascencia,Gloria.
Selenoproteins (Sels) are involved in oxidative stress regulation. Glutathione peroxidase (GPx) and thioredoxin reductase are among the most studied Sels in crustaceans. Since their expressions and activities are affected by pathogens, environmental and metabolic factors, their functions might be key factors to orchestrate the redox cellular balance. The most studied invertebrate selenoproteome is from Drosophila. In this fly, SelD and SelB are involved in selenoproteins synthesis, whereas SelBthD, SelH and SelK are associated with embryogenesis and animal viability. None of the Sels found in Drosophila have been identified in marine crustaceans yet, and their discovery and function identification is an interesting research challenge. SelM has been...
Tipo: Journal article
Palavras-chave: Functions; Invertebrates; Redox; Selenoproteins.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000500017

Nuclear field shift effect in isotope fractionation of thallium
Provedor de dados: 5
Autores: Fujii, Toshiyuki; Moynier, Frederic; Agranier, Arnaud; Ponzevera, Emmanuel; Abe, Minori; Uehara, Akihiro; Yamana, Hajimu.
Environmental transport of Tl is affected by redox reaction between Tl(I) and Tl(III) and ligand exchange reactions of them. In order to deepen the knowledge of Tl chemistry, we investigated fractionation of Tl stable isotopes (Tl-203 and Tl-205) in a chemical exchange system. Tl isotopes were fractionated in a liquid-liquid extraction system, in which aqueous and organic phases are hydrochloric acid solution and dichloroethane including a crown ether, respectively. After purification by ion-exchange chemistry, the isotope ratio of Tl-205/Tl-203 in equilibrated aqueous phase was measured precisely by multiple-collector-inductively-coupled-plasma-mass-spectrometry. A large isotope fractionation &gt; 1 aEuro degrees was found. Electronic structures of...
Tipo: Text
Palavras-chave: Thallium; Isotope fractionation; Redox; Ligand exchange; Nuclear field shift; Ab initio calculation.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00135/24624/22691.pdf

Mercury sources and transformations in a man-perturbed tidal estuary; the Sinnamary Estuary, French Guiana
Provedor de dados: 5
Autores: Muresan, B; Cossa, Daniel; Coquery, M; Richard, S.
The distribution, partition and speciation of mercury (Hg) were studied along the redox gradient of an anthropogenically perturbed tropical estuary, the Sinnamary Estuary in French Guiana. This system is a partially mixed estuary characterized by an anoxic freshwater end-member, while the marine end member consists of the Amazon Plume. The set up of an artificial oxygenation system in the anoxic freshwater end-member generates sharp gradients of major chemical species (iron, sulfides, etc.) coupled with intense organic matter (OM) turnover. The coexistence of oxygenated waters and dissolved sulfides in an organic rich environment depicts the Upper Sinnamary Estuary (USE: part of Sinnamary Estuary under the tidal influence but upstream of the salt...
Tipo: Text
Palavras-chave: Partitioning; Speciation; Redox; Mercury; Reservoir; Estuary.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4223.pdf

New insights into productivity and redox-controlled trace element (Ag, Cd, Re, and Mo) accumulation in a 55 kyr long sediment record from Guaymas Basin, Gulf of California
Provedor de dados: 5
Autores: Chang, Alice S.; Pichevin, Laetitia; Pedersen, Thomas F.; Gray, Victoria; Ganeshram, Raja.
A high-resolution, 55 kyr long record of chalcophile and redox-sensitive trace element accumulation (Ag, Cd, Re, and Mo) from MD02-2515, western Guaymas Basin, is investigated in conjunction with patterns in stratigraphy and productivity. High opal concentrations (~59 wt. %), representing increased diatom production, coincide with laminated sediments and dilute the concentrations of organic carbon (Corg) and metals. A similarity between opal and normalized Corg, Ag, and Cd concentrations suggests delivery to the sediments by diatom export production, while patterns in normalized Re and Mo accumulation suggest a different emplacement mechanism. Although Mo enrichment in organic-rich, laminated sediments typically represents anoxic conditions at other...
Tipo: Text
Palavras-chave: Productivity; Redox; Trace elements; Laminated sediments; Guaymas Basin; Northeast Pacific Ocean.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00294/40566/39461.pdf

Composition des isotopes stables du molybdène dans les carbonates du Précambrien : affinement du proxy et applications paléo-environnementales
Provedor de dados: 5
Autores: Thoby, Mary.
The redox conditions of the oceans evolved considerably during the Precambrian. This is mainly due to the arrival of the oxygen, at first generating oxygen oases, and then accumulating in the atmosphere during the Great Oxidation Event (GOE) ca. 2.45 Ga. However, the earliest traces of free oxygen during these periods, and the mechanisms of their sedimentary expression, remain poorly understood. For over a decade, the isotopic composition of molybdenum (δ98Mo) in sediments has been used as a global marine redox proxy.An elemental and isotopic study of the different phases constituting carbonate rocks was carried out using sequential digestions performed on carbonates of different ages and depositional environments. The results show that Mo is primarily...
Tipo: Text
Palavras-chave: Redox; Précambrien; Carbonates; Molybdène; Isotopes; Attaque séquentielle; Sequential digestion; Precambrian; Molybdenum.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00663/77462/79129.pdf

An experimental study of the partitioning of trace elements between rutile and silicate melt as a function of oxygen fugacity
Provedor de dados: 42
Autores: MALLMANN,GUILHERME; FONSECA,RAÚL O.C.; SILVA,ADOLFO B.
Subduction zone or arc magmas are known to display a characteristic depletion of High Field Strength Elements (HFSE) relative to other similarly incompatible elements, which can be attributed to the presence of the accessory mineral rutile (TiO2) in the residual slab. Here we show that the partitioning behavior of vanadium between rutile and silicate melt varies from incompatible (∼0.1) to compatible (∼18) as a function of oxygen fugacity. We also confirm that the HFSE are compatible in rutile, with D(Ta)&gt; D(Nb)&gt;&gt; (D(Hf)&gt;/∼ D(Zr), but that the level of compatibility is strongly dependent on melt composition, with partition coefficients increasing about one order of magnitude with increasing melt polymerization (or decreasing basicity). Our...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Arc magma; HFSE; Partition coefficient; Redox; Rutile.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000401609

Anti-inflammatory and redox-protective activities of citronellal
Provedor de dados: 48
Autores: Melo,Mônica S; Guimarães,Adriana G; Santana,Michele F; Siqueira,Rosana S; De Lima,Amanda Do Carmo B; Dias,Antonio S; Santos,Márcio Roberto V; Onofre,Alexandre S.C.; Quintans,Jullyana S.S.; De Sousa,Damião P; Almeida,Jackson R.G.S.; Estevam,Charles S; Araujo,Brancilene S; Quintans-Júnior,Lucindo J.
The anti-inflammatory and redox protective effects of the citronellal (CT) were evaluated using in vivo and in vitro tests. Intraperitoneal (i.p.) administration of CT (50, 100, and 200 mg/kg) inhibited (p &lt; 0.05) the carrageenan-induced leukocyte migration to the peritoneal cavity. Additionally, the carrageenan- and arachidonic acid-induced rat hind paw edema was significantly inhibited (p &lt; 0.05) by i.p. administration of 100 and 200 mg/kg of the compound. When the redox activity was evaluated, CT (200 mg/kg) significantly reduced hepatic lipoperoxidation (p &lt; 0.001), as well as oxidation of plasmatic (p &lt; 0.05) and hepatic (p &lt; 0.01) proteins. The results of the present study support the hypothesis that CT possesses anti-inflammatory and...
Tipo: Journal article
Palavras-chave: Monoterpene; Citronellal; Anti-inflammatory; Redox.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602011000400008