Browsing by Subject "Metals"
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- PublicationOpen AccessCopper-Linked Rotaxanes for the Building of Photoresponsive Metal Organic Frameworks with Controlled Cargo Delivery(American Chemical Society, 2020-07-09) Saura Sanmartín, Adrián; Martinez-Cuezva, Alberto; Bautista, Delia; Marzari, Mara R. B.; Martins, Marcos A. P.; Alajarín, Mateo; Berná, José; Berná, José; Química OrgánicaWe have prepared a photoresponsive metal–organic framework by using an amide-based [2]rotaxane as linker and copper(II) ions as metal nodes. The interlocked linker was obtained by the hydrogen bond-directed approach employing a fumaramide thread as template of the macrocyclic component, this latter incorporating two carboxyl groups. Single crystal X-ray diffraction analysis of the metal–organic framework, prepared under solvothermal conditions, showed the formation of stacked 2D rhombohedral grids forming channels decorated with the interlocked alkenyl threads. A series of metal–organic frameworks differing in the E/Z olefin ratio were prepared either by the previous isomerization of the linker or by postirradiation of the reticulated materials. By dynamic solid state 2H NMR measurements, using deuterium-labeled materials, we proved that the geometry of the olefinic axis of the interlocked struts determined the obtention of materials with different independent local dynamics as a result of the strength of the intercomponent noncovalent interactions. Moreover, the usefulness of these novel copper-rotaxane materials as molecular dosing containers has also been assayed by the diffusion and photorelease of p-benzoquinone, evaluated in different solvents and temperatures.
- PublicationRestrictedCytotoxicity and alterations at transcriptional level caused by metals on fish erythrocytes in vitro(Springer, 2016-03-15) Morcillo, Patricia; Romero, Diego; Meseguer, José; Cuesta Peñafiel, Alberto; Esteban Abad, María de los Ángeles; Ciencias SociosanitariasThe in vitro use of fish erythrocytes to test the toxicity of aquatic pollutants could be a valuable alternative to fish bioassays but has received little attention. In this study, erythrocytes from marine gilthead sea bream (Sparus aurata L.) and European sea bass (Dicentrarchus labrax L.) specimens were exposed for 24 h to Cd, Hg, Pb and As and the resulting cytotoxicity was evaluated. Exposure to metals produced a dose-dependent reduction in the viability, and mercury showed the highest toxicity followed by MeHg, Cd, As and Pb. Moreover, fish erythrocytes incubated with each one of the metals exhibited alteration in gene expression profile of metallothionein, superoxide dismutase, catalase, peroxiredoxin, glutathione reductase, heat shock proteins 70 and 90, Bcl2-associated X protein and calpain1 indicating cellular protection, stress and apoptosis death as well as oxidative stress. This study points to the benefits for evaluating the toxicological mechanisms of marine pollution using fish erythrocytes in vitro.
- PublicationOpen AccessEstudio de metales pesados (cd, zn, cu, pb) en el toro de lidia (bos taurus) de diferentes zonas ganaderas y su posible repercusión en la cadena alimentaria(Universidad de Murcia. Servicio de publicaciones, 2024) Pedreño Pérez, Ana; Sanes Vargas, José Manuel; Motas Guzmán, Miguel; Seva Alcaraz, JuanEl ganado de lidia es conocido por su destino a los espectáculos taurinos. Presenta un sistema de producción en régimen extensivo, complementado en algunas fases de su desarrollo por alimentación con concentrados y aportes vitamínico-minerales. Este ganado no está exento, como el resto de los bovinos, de poder padecer la exposición a metales pesados, considerando el peligro potencial que suponen para la cadena alimentaria. El objetivo de este trabajo es evaluar la concentración de metales pesados en el toro de lidia, sus correlaciones y las diferencias entre las diferentes zonas ganaderas. En el siguiente estudio se analizaron las concentraciones de cadmio (Cd), plomo (Pb), cobre (Cu) y zinc (Zn) en 36 toros de lidia de edades comprendidas entre los 48-72 meses criados en un sistema extensivo en las zonas ganaderas de Salamanca, Cádiz, Albacete y Murcia. Los resultados obtenidos se encontraron por debajo de los límites establecidos por ley excepto el Cd (0,23 mg/kg de peso fresco) a nivel muscular. Se encontraron correlaciones del Pb con Cd (CP= 0,487) y Zn (CP= 0,593) a nivel hepático, Pb y Cu (CP= 0,591) en riñón, Cu y Zn (CP= 0,517) en riñón, Cd renal y Zn hepático (CP= 0,418) y el nivel de Cu en riñón y músculo (CP= -0,483). Los animales procedentes de Salamanca presentan menor concentración de Cd en riñón y Cu en hígado, los de Albacete menor concentración de Cd en músculo y los de Murcia mayor concentración de Zn en músculo, lo cual podría ser debido a una causa ambiental. El toro de lidia, debido a su longeva edad productiva, podría considerarse un biomonitor ambiental.
- PublicationOpen AccessFunctionalized Nanoplastics (NPs) Increase the Toxicity of Metals in Fish Cell Lines(MDPI (Basel, Switzerland), 2021) González Fernández, Carmen; Díaz Baños, F. Guillermo; Cuesta Peñafiel, Alberto; Esteban Abad, María de los Ángeles; Química FísicaNanoplastics (NPs) are one of the most abundant environment‐threatening nanomaterials on the market. The objective of this study was to determine in vitro if functionalized NPs are cytotoxic by themselves or increase the toxicity of metals. For that, we used 50 nm polystyrene nanoparticles with distinct surface functionalization (pristine, PS‐Plain; carboxylic, PS‐COOH; and amino PS‐NH2) alone or combined with the metals arsenic (As) and methylmercury (MeHg), which possess an environmental risk to marine life. As test model, we chose a brain‐derived cell line (SaB‐1) from gilthead seabream (Sparus aurata), one of the most commercial fish species in the Mediterranean. First, only the PS‐NH2 NPs were toxic to SaB‐1 cells. NPs seem to be internalized into the cells but they showed little alteration in the transcription of genes related to oxidative stress (nrf2, cat, gr, gsta), cellular protection against metals (mta) or apoptosis (bcl2, bax). However, NPs, mainly PSCOOH and PS‐NH2, significantly increased the toxicity of both metals. Since the coexistence of NPs and other pollutants in the aquatic environment is inevitable, our results reveal that the combined effect of NPs with the rest of pollutants deserves more attention.
- PublicationRestrictedInorganic elements in live vs dead nesting olive ridley marine turtles in the Mexican Pacific: Introducing a new statistical methodology in ecotoxicology(Elsevier, 2020-11-03) Cortés-Gómez, Adriana A.; Romero, Diego; Santos, Juan; Rivera-Hernández, José R.; Girondot, Marc; Ciencias SociosanitariasThis study reports the largest inorganic elements database in the blood of live marine turtles (Lepidochelys olivacea), with 241 live as well as 38 dead nesting turtles sampled and analyzed for 26 inorganic elements, includ ing essential (Al, As, B, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Se, S, V, and Zn) and non-essential elements (Cd, Li, Pb, Sr, Ti, Tl, and Hg). We compared inorganic element concentrations in live and dead olive ridleys from the arribada beach “La Escobilla” located on the Pacific coast of southeastern Mexico. The most outstanding result of our study is the higher Cd concentration in dead (mean 4.27 μg g−1 ww: min 0.01-max 81.5) compared with live animals (mean 0.14 μg g−1 ww: min 0.02-max 0.52). This population has been previously reported to have the highest Cd concentration worldwide in kidney and liver samples from marine turtles (with 150.88 ± 110.99 and 82.88 ± 36.65 μg g−1 ww, respectively). Other important findings of this study include the low Hg concen tration along with the decrease in Pb over the years in this population. The study also uses a new statistical method – the iconography of correlations – in which all available information is used without removing individ uals or variables with missing information for the whole analysis, which is a common problem in ecotoxicology. A major advantage of this method compared to other multivariate methods is that the missing information can be easily handled, because the correlations (2 variables) and partial correlations (3 variables) are estimated only with the available data using a one-at-a-time strategy. ©
- PublicationRestrictedMetals and metalloids in whole blood and tissues of Olive Ridley turtles (Lepidochelys olivacea) from La Escobilla Beach (Oaxaca, Mexico)(Elsevier, 2014-10-06) Cortés-Gómez, Adriana A.; Fuentes-Mascorro, Gisela; Romero García, Diego; Ciencias SociosanitariasConcentrations of eight metals and metalloids (Pb, Cd, Cu, Zn, Mn, Se, Ni and As) were evaluated from 41 nesting females (blood) and 13 dead (tissues) Olive Ridley turtles (Lepidochelys olivacea), a species classified as vulnerable and also listed in Appendix I of the Convention of International Trade in Endangered Species (CITES). The mean blood, liver and kidney lead concentration were 0.02 ± 0.01, 0.11 ± 0.08 and 0.06 ± 0.03 μg g−1 ww respectively, values lower than other turtle species and locations, which it could be due to the gradual disuse of leaded gasoline in Mexico and Central America since the 1990s. Mean concentration of cadmium was 0.17 ± 0.08 (blood), 82.88 ± 36.65 (liver) and 150.88 ± 110.99 μg g−1 (kidney). To our knowledge, the mean renal cadmium levels found is the highest ever reported worldwide for any sea turtle species, while other six elements showed a concentration similar to other studies in sea turtles.
- PublicationEmbargoMolecular oxidative stress markers in olive ridley turtles (Lepidochelys olivacea) and their relation to metal concentrations in wild populations(Elsevier, 2017-10-23) Cortés-Gómez, Adriana A.; Morcillo, Patricia; Espinosa, Cristóbal; Girondot, Marc; Romero, Diego; Cuesta Peñafiel, Alberto; Esteban Abad, María de los Ángeles; Guardiola Abellán, Francisco Antonio; Ciencias SociosanitariasDue to their longevity and extensive migration areas, marine turtles are able to accumulate diverse contaminants over many years and as a consequence they represent an interesting bioindicator species for marine ecosystem pollution. Metals provoke toxicological effects in many aquatic animal species, but marine turtles have been under-investigated in this area. Thus, we have determined the presence of certain inorganic elements (As, Cd, Cu, Ni, Pb, Se and Zn) in olive ridley turtles (Lepidochelys olivacea) and related them to metallothionein (MT), superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) transcription and/or enzymatic activities. Gene expression of sod, cat and gr was found to be higher in blood than liver or kidney but most of the significant relationships were found in liver, not only for gene expression but also for enzyme activities. This must be related to the role the liver has as the first filter organ. Several positive relationships ofsod, cat and gr gene expression in the different tissues were found in this population, as well as very high Cd concentrations. This could mean that these turtles are adapting to the metals-production of ROS and damage through a high transcription of these antioxidants. Multiple positive relationships with GR seem to be part of its compensatory effect due to the decrease of SOD production against the high and chronic exposure to certain xenobiotics. CAT, on the other hand, seems not to be used much, and glutathione detoxification of H2O2 may be more important in this species. Finally, despite the very high Cd concentrations found in this population, no significant relationship was found in any tissue with metallothionein gene expression. These results, along with very high Cd concentrations and a negative relationship with Cu, lead us to consider some kind of disruption in mt gene expression in these turtles.
- PublicationEmbargoThe current situation of inorganic elements in marine turtles: a general review and meta-analysis(Elsevier, 2017-06-24) Cortés-Gómez, Adriana A.; Romero, Diego; Girondot, Marc; Ciencias SociosanitariasInorganic elements (Pb, Cd, Hg, Al, As, Cr, Cu, Fe, Mn, Ni, Se and Zn) are present globally in aquatic systems and their potential transfer to marine turtles can be a serious threat to their health status. The environmental fate of these contaminants may be traced by the analysis of turtle tissues. Loggerhead turtles (Caretta caretta) are the most frequently investigated of all the sea turtle species with regards to inorganic elements, followed by Green turtles (Chelonia mydas); all the other species have considerably fewer studies. Literature shows that blood, liver, kidney and muscle are the tissues most frequently used for the quantification of inorganic elements, with Pb, Cd, Cu and Zn being the most studied elements. Chelonia mydas showed the highest concentrations of Cr in muscle (4.8 ± 0.12), Cu in liver (37 ± 7) and Mg in kidney (17 mg g 1 ww), Cr and Cu from the Gulf of Mexico and Mg from Japanese coasts; Lepidochelys olivacea presented the highest concentrations of Pb in blood (4.46 5) and Cd in kidney (150 ± 110 mg g 1 ww), both from the Mexican Pacific; Caretta caretta from the Mediterranean Egyptian coast had the highest report of Hg in blood (0.66 ± 0.13 mg g 1 ww); and Eretmochelys imbricata from Japan had the highest concentration of As in muscle (30 ± 13 13 mg g 1 ww). The meta-analysis allows us to examine some features that were not visible when data was analyzed alone. For instance, Leatherbacks show a unique pattern of concentration compared to other species. Additionally, contamination of different tissues shows some tendencies independent of the species with liver and kidney on one side and bone on the other being different from other tissues. This review provides a general perspective on the accumulation and distribution of these inorganic elements alongside existing information for the 7 sea turtle species.
- PublicationRestrictedToxic and essential element concentrations in Iberian Ibex (Capra pyrenaica) from the Sierra Nevada Natural Park (Spain): reference intervals in whole blood(Springer, 2015-12-21) Ráez-Bravo, Arián; Granados, José Enrique; Cano-Manuel, Francisco Javier; Soriguer, Ramón C.; Fandos, Paulino; Pérez, Jesús M.; Pavlov, Igor Y.; Romero García, Diego; Ciencias SociosanitariasIberian ibex (Capra pyrenaica) blood samples from the Sierra Nevada Natural Park (Spain) were analyzed to establish concentrations of toxic and essential elements. Samples (whole blood from 32 males and 34 females) were taken from wild animals and the concentrations of inorganic elements considered as (1) non-essential and toxic (Pb, Cd and As), (2) essential but potentially toxic (Cu, Zn and Mn) and (3) occasionally beneficial (B, Cr, Al and Ni), as well as (4) essential minerals (Ca, Na, K, P, Mg, S, Co and Fe), were analyzed. The low concentration of Pb and Cd indicated that there is no heavy metal contamination in this geographical area for these elements. The concentration of elements in this ibex population was defined for different genders and ages. Significant differences between genders were only found for Mg and Cu, while significant differences in concentrations of Ca, Cr, Fe, Mn, P, S and Zn were found between ages.