A Kinetic Approach for Assessing the Uptake of Ag from Pristine and Sulfidized Ag Nanomaterials to Plants.

Nanomaterials (NMs) are thermodynamically unstable by nature, and exposure of soil organisms to NMs in the terrestrial environment cannot be assumed constant. Thus, steady-state conditions may not apply to NMs, and bioaccumulation modeling for uptake should follow a dynamic approach. The one-compartment model allows the uptake and elimination of a chemical to be determined, while also permitting changes in exposure and growth to be taken into account. The aim of the present study was to investigate the accumulation of Ag from different Ag NM types (20 nm Ag0 NMs, 50 nm Ag0 NMs, and 25 nm Ag2 S NMs) in the crop plant wheat (Triticum aestivum). Seeds were emerged in contaminated soils (3 or 10 mg Ag/kg dry soil, nominal) and plants grown for up to 42 d postemergence. Plant roots and shoots were collected after 1, 7, 14, 21, and 42 d postemergence; and total Ag was measured. Soil porewater Ag concentrations were also measured at each sampling time. Using the plant growth rates in the different treatments and the changing porewater concentrations as parameters, the one-compartment model was used to estimate the uptake and elimination of Ag from the plant tissues. The best fit of the model to the data included growth rate and porewater concentration decline, while showing elimination of Ag to be close to zero. Uptake was highest for Ag0 NMs, and size did not influence their uptake rates. Accumulation of Ag from Ag2 S NMs was lower, as reflected by the lower porewater concentrations. Environ Toxicol Chem 2021;40:1861-1872. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Impact of Ag2S NPs on soil bacterial community - A terrestrial mesocosm approach.

Soils might be a final sink for Ag2S nanoparticles (NPs). Still, there are limited data on their effects on soil bacterial communities (SBC). To bridge this gap, we investigated the effects of Ag2S NPs (10 mg kg-1 soil) on the structure and function of SBC in a terrestrial indoor mesocosm, using a multi-species design. During 28 days of exposure, the SBC function-related parameters were analysed in terms of enzymatic activity, community level physiological profile, culture of functional bacterial groups [phosphorous-solubilizing bacteria (P-SB) and heterotrophic bacteria (HB)], and SBC structure was analysed by 16S rRNA gene-targeted denaturing gradient gel electrophoresis. The SBC exposed to Ag2S NPs showed a significative decrease of functional parameters, such as ß-glucosidase activity and L-arginine consumption, and increase of the acid phosphatase activity. At the structural level, significantly lower richness and diversity were detected, but at later exposure times compared to the AgNO3 treatment, likely because of a low dissolution rate of Ag2S NPs. In fact, stronger effects were observed in soils spiked with AgNO3, in both functional and structural parameters. Changes in SBC structure seem to negatively correlate with parameters related to phosphorous (acid phosphatase activity) and carbon cycling (abundance of HB, P-SB, and ß-glucosidase activity). Our results indicate a significant effect of Ag2S NPs on SBC, specifically on parameters related to carbon and phosphorous cycling, at doses as low as 10 mg kg-1 soil. These effects were only observed after 28 days, highlighting the importance of long-term exposure experiments for slowly dissolving NPs.

Inhibition of serotonin receptor type 1 in acute myeloid leukemia impairs leukemia stem cell functionality: a promising novel therapeutic target.

Acute myeloid leukemia (AML) is a clinically and molecularly heterogeneous neoplasia with poor outcome, organized as a hierarchy initiated and maintained by a sub-population with differentiation and self-renewal capacities called leukemia stem cells (LSCs). Although currently used chemotherapy is capable of initially reducing the tumor burden producing a complete remission, most patients will ultimately relapse and will succumb to their disease. As such, new therapeutic strategies are needed. AML cells differentially expressed serotonin receptor type 1 (HTR1) compared with healthy blood cells and the most primitive hematopoietic fraction; in fact, HTR1B expression on AML patient samples correlated with clinical outcome. Inhibition of HTR1s activated the apoptosis program, induced differentiation and reduced the clonogenic capacity, while minimal effect was observed on healthy blood cells. In vivo regeneration capacity of primary AML samples was disrupted upon inhibition of HTR1. The self-renewal capacity remaining in AML cells upon in vivo treatment was severely reduced as demonstrated by serial transplantation. Thus, treatment with HTR1 antagonists showed antileukemia effect, especially anti-LSC activity while sparing healthy blood cells. Our results highlight the importance of HTR1 in leukemogenesis and LSC survival and identify this receptor family as a new target for therapy in AML with prognostic value.

Proyecto de investigación para evaluar la eficacia de los «Cuidados Primarios de Duelo» (CPD) en viudas: un ensayo clínico aleatorizado por médicos / No disponible

Objetivo: evaluar la eficacia de los «Cuidados Primarios de Duelo» (CPD), una intervención biopsicosocial en duelo diseñada específicamente para la atención primaria (AP). Diseño: ensayo clínico aleatorizado por médicos, distribuidos en dos grupos paralelos: control (GC) e intervención (GI). Emplazamiento: 19 Centros de Salud de Vizcaya del Servicio Vasco de Salud/Osakidetza. Participantes: 104 mujeres captadas antes de transcurridos 3 meses del fallecimiento de su pareja y 31 médicos de AP colaboradores. Intervenciones: GI: 7 sesiones de CPD, de 45 minutos cada una, realizadas a los 4, 4½, 5, 6, 8, 10 y 13 meses de la muerte del cónyuge y en lasque se aplicarán las técnicas generales (REFINO: relación, escucha, facilitación, información, normalización y orientación) y específicas (anticipación de fechas, toma de decisiones,...) de los CPD. GC: 7 sesiones realizadas con la misma periodicidad que el GI, pero libres en duración y contenido. Mediciones principales: se analizarán las «mejorías» en el InventarioTexas Revisado de Duelo, Inventario de Experiencias en Duelo, calidad de vida (SF-36) y salud mental (GHQ-28), a los 3, 9, 15 y 21 meses del fallecimiento del cónyuge; mediante análisis de la covarianza ajustado por las variables predictoras y confusoras que se consideren, y con un modelo lineal mixto. Todos los análisis se harán por intención de tratar. Discusión: el proyecto es muy complejo y está lleno de dificultades, pero las conclusiones que se deriven del mismo aportarán evidencias científicas útiles para definir la atención más apropiada a las personas en duelo en AP (AU)

Objective: to evaluate the effectiveness of «Primary BereavementCare» (PBC), a bereavement intervention specifically designed for primary health care (PHC). Design: a cluster (family physicians)-randomized controlled trial. Location: 19 Basque Health Service (Osakidetza) Centers in Biscay. Participants: 104 women selected within 3 months of their partners' demise, and 31 collaborating family physicians. Interventions: experimental group: 7 sessions of 45 minutes each, performed at 4, 4½, 5, 6, 8, 10 and 13 months after partner death, applying PBC general techniques (REFINO: relationship, «ear», facilitation, information, normalization, and orientation) and PBC specific techniques(date anticipation, decision taking, etc.). Control group: 7 sessions with the same frequency, but without specific content and duration. Principal measurements: «improvements» are analyzed according tothe Texas Revised Inventory of Grief, Grief Experiences Inventory, qualityof life (SF-36) and mental health (GHQ-28), at 3, 9, 15 and 21 monthsfollowing the partner's death; via a covariance analysis adjusted by predictedand confounding variables, using a mixed linear model. All analyses will be performed on an intention-to-treat basis. Discussion: the project is very complex and full of difficulties, but theconclusions obtained will provide useful scientific evidence for the definitionof the most appropriate care for the bereaved in PHC (AU)