Search results for "Cadmi"
showing 10 items of 442 documents
The metal binding abilities of Megathura crenulata metallothionein (McMT) in the frame of gastropoda MTs.
2011
Metallothioneins (MTs) are proteins that play a major role in metal homeostasis and/or detoxification in all kind of organisms. The MT gene/protein system of gastropod molluscs provides an invaluable model to study the diversification mechanisms that have enabled MTs to achieve metal-binding specificity through evolution. Most pulmonate gastropods, particularly terrestrial snails, harbor three paralogous isogenes encoding three MT isoforms with different metal binding preferences: the highly specific CdMT and CuMT isoforms, for cadmium and copper respectively, and the unspecific Cd/CuMT isoform. Megathura crenulata is a non-pulmonate gastropod in which only one MT isogene has so far been re…
Chemical and biochemical responses to sub−lethal doses of mercury and cadmium in gilthead seabream (Sparus aurata)
2022
Specimens of Sparus aurata were exposed to sub-lethal concentrations of Hg and Cd for 25 days and the levels of both metals were investigated in organs and tissues. Bioaccumulation of Hg decreased as follow: gills > kidney > liver > skin > muscle, while the order of Cd bioaccumulation was: liver > kidney > gills > skin > muscle. Immediately after exposure, both metals showed the highest bioaccumulation in gills and skin indicating that these organs are reliable targets for biomonitoring studies after short term exposure. Metals introduction caused a significant time-dependent concentrations increase in kidney and liver, while in the muscle a significant in-crease of …
Cadmium, mercury, and lead effects on gill tissue of freshwater crayfishProcambarus clarkii (girard)
1989
Intermolt adult crayfish P. clarkii were used for this work. After acclimatization to laboratory conditions crayfish were exposed to sublethal concentrations of cadmium, mercury, and lead for 96 h. Gills of control and exposed crayfish were removed and ATPase activity and oxygen uptake rate were determined. Structural damage of gill filaments was also observed. Gill tissue respiration rates were measured for individual crayfish using a Gilson differential respirometer. Lead causes a decrease of gill oxygen uptake, but neither cadmium nor mercury seems to affect it at the concentrations employed. Although all metals studied alter gill filament structure, lead damage is the most apparent. In …
Effects of cadmium on the biochemical composition of the freshwater crayfishProcambarus clarkii (Girard, 1852)
1991
Lake Albufera of Valencia (Spain) and the surrounding rice field waters are subjected to very heavy loads of sewage and toxic residues. Among these residues include heavy metals which have been deposited from the many urban and waste waters in this area. The American red crayfish, Procambarus clarkii from Albufera Lake has high resistance to heavy metals. The authors have also found that P. clarkii shows a high capacity for cadmium accumulation in experimental conditions and natural conditions since crayfish collected in this area contained considerable amounts of cadmium in several tissues even after 15 days of depuration in clean water. Since the physiological changes that take place when…
Interaction of metal ions with N-glycosylamines: isolation and characterization of the products of 4,6-O-benzylidene-N-(o-carboxyphenyl)-β-D-glucopyr…
2001
Metal-ion complexes of Li+, Na+, K+, Mg2+, Ca2+, Ba2+, Pb2+, Cd2+, Hg2+ with 4,6–O–benzylidene–N–(o–carboxyphenyl)–β–D–glucopyranosylamine were synthesized and isolated as solid products and characterized by analytical means as well as by spectral techniques, such as, 1H and 13C NMR, FTIR, absorption, FAB mass spectrometry, optical rotation and CD. While the alkali metal ions formed ML type of complexes, the other metal ions formed ML2 type complexes. Molecular weights of the complexes of Li+, Na+ and K+ were established based on the molecular-ion peaks in the FAB mass spectra. The saccharide portion remians in the β-anomeric form even after the complexation. The spectral data, as well as t…
Single and competitive adsorption of Cd and Zn onto a granular activated carbon
1996
Single and competitive adsorption of cadmium and zinc onto granular activated carbon DARCO 12–20 mesh has been investigated. This activated carbon has been shown as an effective adsorbent for both metals. Cadmium and zinc removals increased with pH and decreased with molar metal/carbon ratio. Surface precipitation phenomena have been detected for the higher pHs and molar ratios. The adsorption process has been modelled on the surface complexation Triple Layer Model (TLM). For this purpose, the amphoteric nature of the activated carbon has been studied. Single metal adsorption data have been used to calibrate TLM parameters. A dependence of the adsorption constants on pH and molar metal/carb…
Biomarkers, matrices and analytical methods targeting human exposure to chemicals selected for a European human biomonitoring initiative
2020
E-mail addresses: kvo@envs.au.dk (K. Vorkamp), Castano@isciii.es (A. Castaño), Jean-Philippe.Antignac@oniris-nantes.fr (J.-P. Antignac), Luis.Boada@ulpgc.es (L.D. Boada), ECequier@quimica.udl.cat (E. Cequier), Adrian.Covaci@uantwerpen.be (A. Covaci), M.Esteban@isciii.es (M. Esteban López), LineSmastuen.Haug@fhi.no (L.S. Haug), Kasper@ipa-dguv.de (M. Kasper-Sonnenberg), Koch@ipa-dguv.de (H.M. Koch), Octavio.Perez@ulpgc.es (O. Pérez Luzardo), Agnese.Osite@lu.lv (A. Osīte), Loic.Rambaud@santepubliquefrance.fr (L. Rambaud), mtpin@ticino.com (M.-T. Pinorini), Gabriele.Sabbioni@bluewin.ch (G. Sabbioni), Cathrine.Thomsen@fhi.no (C. Thomsen).; International audience; The major purpose of human biom…
Country-specific correlations across Europe between modelled atmospheric cadmium and lead deposition and concentrations in mosses
2012
Previous analyses at the European scale have shown that cadmium and lead concentrations in mosses are primarily determined by the total deposition of these metals. Further analyses in the current study show that Spearman rank correlations between the concentration in mosses and the deposition modelled by the European Monitoring and Evaluation Programme (EMEP) are country and metal-specific. Significant positive correlations were found for about two thirds or more of the participating countries in 1990, 1995, 2000 and 2005 (except for Cd in 1990). Correlations were often not significant and sometimes negative in countries where mosses were only sampled in a relatively small number of EMEP gr…
Metallothionein in the freshwater gastropod Melanopsis dufouri chronically exposed to cadmium: A methodological approach
2010
Previous studies have demonstrated that the use of differential pulse polarography (DPP) for metallothionein (MT) determination in marine gastropod tissues, particularly the digestive gland, requires taking into account the presence of heat-stable high molecular weight compounds that exhibit polarographic signal. In the present paper, similar compounds were identified in tissues from the freshwater snail Melanopsis dufouri which also interfere with MT determination by DPP and, due to their silver binding capacity, also interfere in the silver assay for MT quantification. Ultrafiltration seems to be effective in removing these high molecular weight compounds from heat-denatured homogenate su…
Assessment of metal levels in foodstuffs from the Region of Valencia (Spain).
2017
Graphical abstract