Bioaccumulation of titanium dioxide nanoparticles in green (Ulva sp.) and red (Palmaria palmata) seaweed

A bioaccumulation study in red (Palmaria palmata) and green (Ulva sp.) seaweed has been carried out after exposure to different concentrations of citrate-coated titanium dioxide nanoparticles (5 and 25 nm) for 28 days. The concentration of total titanium and the number and size of accumulated nanoparticles in the seaweeds has been determined throughout the study by inductively coupled plasma mass spectrometry (ICP-MS) and single particle-ICP-MS (SP-ICP-MS), respectively. Ammonia was used as a reaction gas to minimize the effect of the interferences in the 48Ti determination by ICP-MS. Titanium concentrations measured in Ulva sp. were higher than those found in Palmaria palmata for the same exposure conditions. The maximum concentration of titanium (61.96 ± 15.49 μg g−1) was found in Ulva sp. after 28 days of exposure to 1.0 mg L−1 of 5 nm TiO2NPs. The concentration and sizes of TiO2NPs determined by SP-ICP-MS in alkaline seaweed extracts were similar for both seaweeds exposed to 5 and 25 nm TiO2NPs, which indicates that probably the element is accumulated in Ulva sp. mainly as ionic titanium or nanoparticles smaller than the limit of detection in size (27 nm). The implementation of TiO2NPs in Ulva sp. was confirmed by electron microscopy (TEM/STEM) in combination with energy dispersive X-Ray analysis (EDX)The authors wish to thank the fnancial support of Ministerio de Economía y Competitividad (project INNOVANANO, reference RT2018-099222-B-100), European Union (INTERREG Atlantic Area, project NANOCULTURE, reference EAPA590/2018), and Xunta de Galicia (Grupo de Referencia Competitiva, grant number ED431C 2022/29)S

Development and validation of a clinical score to estimate progression to severe or critical state in Covid-19 pneumonia hospitalized patients

The prognosis of a patient with Covid-19 pneumonia is uncertain. Our objective was to establish a predictive model of disease progression to facilitate early decision-making. A retrospective study was performed of patients admitted with Covid-19 pneumonia, classified as severe (admission to the intensive care unit, mechanic invasive ventilation, or death) or non-severe. A predictive model based on clinical, analytical, and radiological parameters was built. The probability of progression to severe disease was estimated by logistic regression analysis. Calibration and discrimination (receiver operating characteristics curves and AUC) were assessed to determine model performance. During the study period 1,152 patients presented with Covid-19 infection, of whom 229 (19.9%) were admitted for pneumonia. During hospitalization, 51 (22.3%) progressed to severe disease, of whom 26 required ICU care (11.4); 17 (7.4%) underwent invasive mechanical ventilation, and 32 (14%) died of any cause. Five predictors determined within 24 hours of admission were identified: Diabetes, Age, Lymphocyte count, SaO2, and pH (DALSH score). The prediction model showed a good clinical performance, including discrimination (AUC 0.87 CI 0.81, 0.92) and calibration (Brier score = 0.11). In total, 0%, 12%, and 50% of patients with severity risk scores ≤5%, 6-25%, and >25% exhibited disease progression, respectively. A simple risk score based on five factors predicts disease progression and facilitates early decision-making according to prognosis.Carlos III Health Institute, Spain, Ministry of Economy and Competitiveness (SPAIN) and the European Regional Development Fund (FEDER)Instituto de Salud Carlos II

Bioaccumulation and bioavailability studies of silver and titanium dioxide nanoparticles in aquaculture products

Silver and titanium dioxide nanoparticles are commonly used in industry, can be emitted into the environment, interact with different organisms, and therefore they can be considered emergent contaminants. This doctoral thesis focuses on the bioaccumulation and bioavailability studies of these materials in some of the most important aquaculture species of the Atlantic area, including seaweed, mussels, and turbot. Different methodologies for silver and titanium dioxide nanoparticles extraction from the aquaculture matrices were used and developed. They were also applied to the study of the presence of nanoparticles in marine samples from Ireland, France and UK. Furthermore, the potential release of nanoparticles from the food matrix to the systemic circulation and the intestinal epithelial cells was assessed after simulated in vitro gastrointestinal digestions and transport through Caco-2 cells by SP-ICP-MS and SC-ICP-MS

Ultrasonication followed by enzymatic hydrolysis as a sample pre-treatment for the determination of Ag nanoparticles in edible seaweed by SP-ICP-MS

Seaweed can bioaccumulate nanomaterials that would be transferred to the trophic chain. This work describes the optimization of a method for the separation of silver nanoparticles (AgNPs) from seaweed using an ultrasound-assisted enzymatic hydrolysis method and ulterior determination by single particle inductively coupled plasma mass spectrometry (SP-ICP-MS). The following parameters affecting the isolation of AgNPs were optimized using a Palmaria palmata (red seaweed) sample previously exposed to AgNPs: type of sonication (bath vs. ultrasonic probe), ultrasound amplitude, sonication time, sonication mode (pulsed vs. continuous sonication), concentration of the enzymes mixture (Macerozyme R-10®), and enzymatic hydrolysis time. The stability of AgNPs during extraction was tested by transmission electron microscopy (TEM) and using a standard of 15 nm of polyvinylpyrrolidone (PVP)-coated AgNPs analyzed by SP-ICP-MS. The analytical performance was evaluated with good results. For total Ag determination, the limits of detection and quantification were 2.2 and 7.7 ng g−1, respectively; and for AgNPs determination, the limits of detection in size and number were 14 nm and 4.34 × 107 part g−1, respectively. Besides, the matrix effect, the repeatability and the analytical recovery were also studied. Finally, the method was applied to the analysis of several red (Palmaria palmata) and green (Ulva sp.) seaweed samplesThe authors wish to acknowledge the financial support of Ministerio de Economía y Competitividad (project INNOVANANO, reference RT2018-099222-B-100), European Union (INTERREG Atlantic Area, project NANOCULTURE, reference EAPA590/2018), and Xunta de Galicia (Grupo de Referencia Competitiva, grant number ED431C2018/19)S

Proteomics reveals multiple effects of titanium dioxide and silver nanoparticles in the metabolism of turbot, Scophthalmus maximus

Titanium dioxide (TiO2) and silver (Ag) NPs are among the most used engineered inorganic nanoparticles (NPs); however, their potential effects to marine demersal fish species, are not fully understood. Therefore, this study aimed to assess the proteomic alterations induced by sub-lethal concentrations citrate-coated 25 nm ("P25") TiO2 or polyvinylpyrrolidone (PVP) coated 15 nm Ag NPs to turbot, Scophthalmus maximus. Juvenile fish were exposed to the NPs through daily feeding for 14 days. The tested concentrations were 0, 0.75 or 1.5 mg of each NPs per kg of fish per day. The determination of NPs, Titanium and Ag levels (sp-ICP-MS/ICP-MS) and histological alterations (Transmission Electron Microscopy) supported proteomic analysis performed in the liver and kidney. Proteomic sample preparation procedure (SP3) was followed by LC-MS/MS. Label-free MS quantification methods were employed to assess differences in protein expression. Functional analysis was performed using STRING web-tool. KEGG Gene Ontology suggested terms were discussed and potential biomarkers of exposure were proposed. Overall, data shows that liver accumulated more elements than kidney, presented more histological alterations (lipid droplets counts and size) and proteomic alterations. The Differentially Expressed Proteins (DEPs) were higher in Ag NPs trial. The functional analysis revealed that both NPs caused enrichment of proteins related to generic processes (metabolic pathways). Ag NPs also affected protein synthesis and nucleic acid transcription, among other processes. Proteins related to thyroid hormone transport (Serpina7) and calcium ion binding (FAT2) were suggested as biomarkers of TiO2 NPs in liver. For Ag NPs, in kidney (and at a lower degree in liver) proteins related with metabolic activity, metabolism of exogenous substances and oxidative stress (e.g.: NADH dehydrogenase and Cytochrome P450) were suggested as potential biomarkers. Data suggests adverse effects in turbot after medium/long-term exposures and the need for additional studies to validate specific biological applications of these NPs.Funding: European Regional Development Fund (ERDF) through Interreg Atlantic Area Program, project NANO -CULTURE [EAPA 590/2018]; Portuguese Foundation for Science and Technology (Fundacao para a Ciencia e Tecnologia; FCT) [UIDB/04423/2020, UIDP/04423/2020]</p