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1.
Biol Rev Camb Philos Soc ; 99(1): 131-176, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37698089

RESUMEN

Aquatic invertebrates play a pivotal role in (eco)toxicological assessments because they offer ethical, cost-effective and repeatable testing options. Additionally, their significance in the food chain and their ability to represent diverse aquatic ecosystems make them valuable subjects for (eco)toxicological studies. To ensure consistency and comparability across studies, international (eco)toxicology guidelines have been used to establish standardised methods and protocols for data collection, analysis and interpretation. However, the current standardised protocols primarily focus on a limited number of aquatic invertebrate species, mainly from Arthropoda, Mollusca and Annelida. These protocols are suitable for basic toxicity screening, effectively assessing the immediate and severe effects of toxic substances on organisms. For more comprehensive and ecologically relevant assessments, particularly those addressing long-term effects and ecosystem-wide impacts, we recommended the use of a broader diversity of species, since the present choice of taxa exacerbates the limited scope of basic ecotoxicological studies. This review provides a comprehensive overview of (eco)toxicological studies, focusing on major aquatic invertebrate taxa and how they are used to assess the impact of chemicals in diverse aquatic environments. The present work supports the use of a broad-taxa approach in basic environmental assessments, as it better represents the natural populations inhabiting various ecosystems. Advances in omics and other biochemical and computational techniques make the broad-taxa approach more feasible, enabling mechanistic studies on non-model organisms. By combining these approaches with in vitro techniques together with the broad-taxa approach, researchers can gain insights into less-explored impacts of pollution, such as changes in population diversity, the development of tolerance and transgenerational inheritance of pollution responses, the impact on organism phenotypic plasticity, biological invasion outcomes, social behaviour changes, metabolome changes, regeneration phenomena, disease susceptibility and tissue pathologies. This review also emphasises the need for harmonised data-reporting standards and minimum annotation checklists to ensure that research results are findable, accessible, interoperable and reusable (FAIR), maximising the use and reusability of data. The ultimate goal is to encourage integrated and holistic problem-focused collaboration between diverse scientific disciplines, international standardisation organisations and decision-making bodies, with a focus on transdisciplinary knowledge co-production for the One-Health approach.


Asunto(s)
Artrópodos , Ecosistema , Animales , Humanos , Invertebrados
2.
Small ; 13(20)2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28374954

RESUMEN

Materials with controllable multifunctional abilities for optical imaging (OI) and magnetic resonant imaging (MRI) that also can be used in photodynamic therapy are very interesting for future applications. Mesoporous TiO2 sub-micrometer particles are doped with gadolinium to improve photoluminescence functionality and spin relaxation for MRI, with the added benefit of enhanced generation of reactive oxygen species (ROS). The Gd-doped TiO2 exhibits red emission at 637 nm that is beneficial for OI and significantly improves MRI relaxation times, with a beneficial decrease in spin-lattice and spin-spin relaxation times. Density functional theory calculations show that Gd3+ ions introduce impurity energy levels inside the bandgap of anatase TiO2 , and also create dipoles that are beneficial for charge separation and decreased electron-hole recombination in the doped lattice. The Gd-doped TiO2 nanobeads (NBs) show enhanced ability for ROS monitored via • OH radical photogeneration, in comparison with undoped TiO2 nanobeads and TiO2 P25, for Gd-doping up to 10%. Cellular internalization and biocompatibility of TiO2 @xGd NBs are tested in vitro on MG-63 human osteosarcoma cells, showing full biocompatibility. After photoactivation of the particles, anticancer trace by means of ROS photogeneration is observed just after 3 min irradiation.


Asunto(s)
Gadolinio/química , Luminiscencia , Nanopartículas/química , Neoplasias/diagnóstico , Neoplasias/terapia , Especies Reactivas de Oxígeno/metabolismo , Marcadores de Spin , Titanio/química , Catálisis , Línea Celular Tumoral , Supervivencia Celular , Teoría Funcional de la Densidad , Humanos , Radical Hidroxilo/química , Imagen por Resonancia Magnética , Nanopartículas/ultraestructura , Imagen Óptica , Porosidad , Temperatura , Rayos Ultravioleta , Difracción de Rayos X
3.
Environ Toxicol Chem ; 33(4): 858-67, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24812678

RESUMEN

The effect of ultraviolet-A irradiated or nonirradiated suspensions of agglomerates of titanium dioxide (TiO(2)) or silicon dioxide (SiO(2)) nanoparticles on roots of the onion (Allium cepa) has been studied. The reactive potential of TiO(2) nanoparticles, which have photocatalytic potential, and the nonphotocatalytic SiO(2) nanoparticles with the same size of agglomerates was compared. The authors measured the activity of antioxidant enzymes glutathione reductase, ascorbate peroxidase, guaiacol peroxidase, and catalase as well as lipid peroxidation to assess the oxidative stress in exposed A. cepa roots. A wide range of concentrations of nanoparticles was tested (0.1-1000 µg/mL). The sizes of agglomerates ranged in both cases from 300 nm to 600 nm, and the exposure time was 24 h. Adsorption of SiO(2) nanoparticles on the root surface was minimal but became significant when roots were exposed to TiO(2) agglomerates. No significant biological effects were observed even at high exposure concentrations of SiO(2) and TiO(2) nanoparticles individually. Plants appear to be protected against nanoparticles by the cell wall, which shields the cell membrane from direct contact with the nanoparticles. The authors discuss the need to supplement conventional phytotoxicity and stress end points with measures of plant physiological state when evaluating the safety of nanoparticles.


Asunto(s)
Nanopartículas/toxicidad , Cebollas/efectos de los fármacos , Raíces de Plantas/efectos de los fármacos , Dióxido de Silicio/toxicidad , Titanio/toxicidad , Rayos Ultravioleta , Ascorbato Peroxidasas/metabolismo , Catalasa/metabolismo , Glutatión Reductasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Nanopartículas/efectos de la radiación , Cebollas/metabolismo , Cebollas/efectos de la radiación , Estrés Oxidativo/efectos de los fármacos , Peroxidasa/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Raíces de Plantas/efectos de la radiación , Dióxido de Silicio/efectos de la radiación , Titanio/efectos de la radiación
4.
Protoplasma ; 249(3): 835-42, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21688199

RESUMEN

Isolated digestive gland epithelium from a model invertebrate organism was used in an ex vivo system to assess the potential of nanoparticulate TiO(2) to disrupt cell membranes. Primary particle size, surface area, concentration of particles in a suspension, and duration of exposure to TiO(2) particles were all found to have effects, which are observed at concentrations of nano-TiO(2) as low as 1 µg mL(-1). The test system employed here can be used as a fast screening tool to assess biological potential of nanoparticles with similar chemical composition but different size, concentration, or duration of exposure. We discuss the potential of ex vivo tests to avoid some of the limitations of conventional in vitro tests.


Asunto(s)
Permeabilidad de la Membrana Celular/efectos de los fármacos , Sistema Digestivo/efectos de los fármacos , Nanopartículas/toxicidad , Titanio/toxicidad , Animales , Membrana Celular/efectos de los fármacos , Sistema Digestivo/citología , Evaluación Preclínica de Medicamentos , Epitelio/efectos de los fármacos , Técnicas In Vitro , Isópodos , Nanopartículas/química , Tamaño de la Partícula , Propiedades de Superficie , Titanio/química
5.
Sci Total Environ ; 304(1-3): 231-56, 2003 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-12663187

RESUMEN

The province of Guizhou in Southwestern China is currently one of the world's most important mercury production areas. Emissions of mercury from the province to the global atmosphere have been estimated to be approximately 12% of the world total anthropogenic emissions. The main objective of this study was to assess the level of contamination with Hg in two geographical areas of Guizhou province. Mercury pollution in the areas concerned originates from mercury mining and ore processing in the area of Wanshan, while in the area of Quingzhen mercury pollution originates from the chemical industry discharging Hg through wastewaters and emissions to the atmosphere due to coal burning for electricity production. The results of this study confirmed high contamination with Hg in soil, sediments and rice in the Hg mining area in Wanshan. High levels of Hg in soil and rice were also found in the vicinity of the chemical plant in Quingzhen. The concentrations of Hg decreased with distance from the main sources of pollution considerably. The general conclusion is that Hg contamination in Wanshan is geographically more widespread, due to deposition and scavenging of Hg from contaminated air and deposition on land. In Quingzhen Hg contamination of soil is very high close to the chemical plant but the levels reach background concentrations at a distance of several km. Even though the major source of Hg in both areas is inorganic Hg, it was observed that active transformation of inorganic Hg to organic Hg species (MeHg) takes place in water, sediments and soils. The concentration of Hg in rice grains can reach up to 569 microg/kg of total Hg of which 145 microg/kg was in MeHg form. The percentage of Hg as MeHg varied from 5 to 83%. The concentrations of selenium can reach up to 16 mg/kg in soil and up to 1 mg/g in rice. A correlation exists between the concentration of Se in soil and rice, indicating that a portion of Se is bioavailable to plants. No correlation between Hg and Se in rice was found. Exposure of the local population to Hg may occur due to inhalation of Hg present in air (in particular in Hg mining area) and consumption of Hg contaminated food (in particular rice and fish) and water. Comparison of intake through these different routes showed that the values of Hg considerably exceed the USA EPA Reference Concentration (RfC) for chronic Hg exposure (RfC is 0.0004 mg/m(3)) close to the emission sources. Intake of Hg through food consumption, particularly rice and fish, is also an important route of Hg exposure in study area. In general, it can be concluded that the population mostly at risk is located in the vicinity of smelting facilities, mining activities and close to the waste disposal sites in the wider area of Wanshan. In order to assess the real level of contamination in the local population, it is recommended that biomonitoring should be performed, including Hg and MeHg measurements in hair, blood and urine samples.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación de Alimentos , Mercurio/análisis , Compuestos de Metilmercurio/análisis , Selenio/análisis , Contaminantes del Suelo/análisis , Animales , Disponibilidad Biológica , Industria Química , China , Monitoreo del Ambiente , Peces , Humanos , Oryza/química , Salud Pública
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