Role of UV radiation and oxidation on polyethylene micro- and nanoplastics: impacts on cadmium sorption, bioaccumulation, and toxicity in fish intestinal cells.

This study investigated the role of ultraviolet (UV) radiation and oxidation in high-density polyethylene microplastics (2-15 µm) and nanoplastics (0.2-9.9 µm) (NMPs) on particle chemistry, morphology, and reactivity with cadmium (Cd). Additionally, toxicity of NMPs alone and with Cd was evaluated using RTgutGC cells, a model of the rainbow trout (Oncorhynchus mykiss) intestine. The role on NMPs on Cd bioaccumulation in RTgutGC cells was also evaluated. Dynamic light scattering indicated that after UV radiation NPs agglomerated size increased from 0.8 to 28 µm, and to 8 µm when Cd was added. Oxidized MPs agglomerated size increased from 11 and 7 to 46 and 27 µm in non-UV- and UV-aged oxidized MPs when adding Cd, respectively. Cd-coated particles exhibited generally significantly higher zeta potential than non-Cd-coated particles, while attenuated total reflectance-Fourier transform infrared spectroscopy showed that the functional chemistry of the particles was oxidized and modified after being exposed to UV radiation. Presence of NMPs resulted in a significant decrease in Cd bioaccumulation in RTgutGC cells (100.5-87.9 ng Cd/mg protein) compared to Cd alone (138.1 ng Cd/mg protein), although this was not quite significant for co-exposures with UV-aged NPs (105.7 ng Cd/mg protein). No toxicity was observed in RTgutGC cells exposed to NMPs alone for 24 h. Moreover, co-exposures with Cd indicated that NMPs reduce the toxicity of Cd. Altogether these results show that UV aging enhances NMP surface reactivity, increasing Cd absorption in solution, which resulted in a reduction in Cd bioavailability and toxicity.

Comparative assessment of microplastics and microalgae as vectors of mercury and chlorpyrifos in the copepod Acartia tonsa.

Microplastics (MPs) raise concerns not only as pollutants themselves, but also due to their ability to act as vectors of pollutants adsorbed from seawater, transferring them to marine organisms. However, the relevance of MPs as carriers of pollutants compared to microalgae needs further exploration. This study compared the role of MPs (2-10 µm non-oxidized and 10-15 µm oxidized high-density polyethylene) and natural organic particles (Rhodomonas lens microalgae, MA) as carriers of mercury (Hg, 2.3 µg Hg/L) and chlorpyrifos (CPF, 1.0 µg CPF/L) to adult Acartia tonsa copepods, after 24-48 h exposure. Dose-response experiments were first performed with adult female copepods exposed to oxidized MPs (0.25-4.0 mg/L), waterborne Hg (0.01-10.0 µg/L) and Ox MPs + Hg (0.25-4.0 mg oxidized MPs/L + 0.50-8.0 µg Hg/L) for 48 h, to complement previous studies that focused on the pesticide CPF. Effects were evaluated with four replicates for physiological and reproductive responses (6 females/replicate), biochemical techniques (40 individuals/replicate) and Hg/CPF bioaccumulation measurements (1000 individuals/replicate). Copepods accumulated Hg/CPF similarly from dissolved pollutants (6204 ± 2265 ng Hg/g and 1251 ± 646 ng CPF/g) and loaded MPs (3125 ± 1389 ng Hg/g and 1156 ± 266 ng CPF/g), but significantly less from loaded MA (21 ± 8 ng Hg/g and 173 ± 80 ng CPF/g). After 24-48 h, copepods exposed to MPs + Hg/CPF showed generally greater biological effects than those exposed to dissolved Hg/CPF or to MA + Hg/CPF, although differences were not statistically significant. MA + CPF had significantly lower AChE inhibition (1073.4 nmol min-1 mg-1) and MA + Hg lower GRx induction (48.8 nmol min-1 mg-1) compared to MPs + Hg/CPF and dissolved Hg/CPF (182.8-236.4 nmol min-1 mg-1 of AChE and 74.1-101.7 nmol min-1 mg-1 of GRx). Principal component analysis suggested different modes of action for Hg and CPF.

De estar "toda Teletubbie" a ser Verónica: utilidad de las sesiones de observación (sesiones diagnósticas) para trazar el proceso evolutivo de un sufrimiento mental / From Being "Completely Teletubbie" to Being Veronica: Usefulness of Observation Sessions (Diagnostic Sessions) in Tracing the Evolutionary Process of a Mental Suffering

Introducción: En este estudio se usa un modelo evolutivo de los trastornos y del desarrollo del psiquismo que permite tener una visión global del paciente, en el cual concurre no sólo lo que podría aportar la genética, sino todas las distorsiones producto de las experiencias con el ambiente. Las teorías sobre el desarrollo psíquico han mostrado que el nacimiento, la construcción y la organización del psiquismo de un individuo deben comprenderse como una progresión evolutiva. Objetivo: Mostrar a través de una sesión de observación cómo se comprende la organización psíquica de una paciente y el origen y posterior evolución de sus trastornos. Método: Observación de un caso particular de interacción de una paciente con su madre, su abuela y un equipo de trabajo y, luego, este último reflexionó sobre diversas hipótesis, que surgieron de la comprensión de las relaciones entre la psicopatología de la paciente y las teorías del desarrollo psíquico. Resultados: En el caso ilustrado se descartó el diagnóstico de autismo con el cual venía remitida la paciente, pues los síntomas de esta paciente podrían verse desde la perspectiva de las primeras relaciones interpersonales. Las teorías actuales sobre el desarrollo psíquico permiten comprender que no se trata de algo "que le dio", sino que se fue gestando desde muy temprano en la vida emocional de este ser. Conclusión: En esta sesión de observación se ve cómo estas citas, que inicialmente fueron establecidas para diagnosticar, conducen a una profunda comprensión del paciente, que al ser compartida con sus padres, tiene también un efecto terapéutico y se constituyen así en "consultas terapéuticas", como las propuestas por D. W. Winnicott.

Introduction: In this study an evolutionary model of the disorders and the development of psychism is used, that allows achiving an overall vision of the patient and which combines not only what could contribute to genetics, but all the distortions resulting from experiences with the environment. The theories about psychic development have shown that the birth, building and organization of the psychism of an individual must be understood as an evolutionary progression. Objective: To show, by means of an observation session, how the psychic organization of a female patient and the subsequent evolution of her disorders may be understood. Method: Observing an individual case of interaction between a female patient and her mother, grandmother and a work team. Subsequently this team discussed different hypothesis that emerged from the understanding of the relationships between the patient’s psicopathology and the psychic development theories. Results: In this case the diagnosis of autism, with which the patient was remitted, was ruled out because the symptoms of this patient could be seen from the perspective of first interpersonal relationships. Current theories on psychic development allow understanding that it is not "just something that she got", but that it started developing very early in the emotional life of this being. Conclusion: In this observation session it is apparent how these visits, which initially were established to reach a diagnosis, lead to a deep understanding of the patient that, when shared with her parents, have a therapeutic effect and become "therapeutic consultations" as those proposed by D.W. Winnicott.