Gadolinium toxicity on sea urchin embryos of geographically and phylogenetically distant species

Pharmaceuticals are a class of emerging environmental contaminants. Gadolinium (Gd) is a metal of the lanthanide series of the elements whose chelates are commonly employed as contrast agents for magnetic resonance imaging, and subsequently released into the aquatic environment. We investigated the consequences of sea urchin embryo exposure to sublethal Gd concentrations, comparing the effects on the development of four phylogenetically and geographically distant species: two Mediterranean species, Paracentrotus lividus and Arbacia lixula, and two species living in the East coast of Australia, Heliocidaris tuberculata and Centrostephanus rodgersii. Measures of the Gd and Ca content inside e…

Impact of Safety-Related Dose Reductions or Discontinuations on Sustained Virologic Response in HCV-Infected Patients: Results from the GUARD-C Cohort.

Background: Despite the introduction of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, peginterferon alfa/ribavirin remains relevant in many resource-constrained settings. The non-randomized GUARD-C cohort investigated baseline predictors of safety-related dose reductions or discontinuations (sr-RD) and their impact on sustained virologic response (SVR) in patients receiving peginterferon alfa/ribavirin in routine practice. Methods: A total of 3181 HCV-mono-infected treatment-naive patients were assigned to 24 or 48 weeks of peginterferon alfa/ribavirin by their physician. Patients were categorized by time-to-first sr-RD (Week 4/12). Detailed analyses of the i…

Safety and efficacy of non-steroidal anti-inflammatory drugs to reduce ileus after colorectal surgery

Ileus is common after elective colorectal surgery, and is associated with increased adverse events and prolonged hospital stay. The aim was to assess the role of non-steroidal anti-inflammatory drugs (NSAIDs) for reducing ileus after surgery.A prospective multicentre cohort study was delivered by an international, student- and trainee-led collaborative group. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The primary outcome was time to gastrointestinal recovery, measured using a composite measure of bowel function and tolerance to oral intake. The impact of NSAIDs was explored using Cox regression analyses, including the results of a c…

The toxic effect of gadolinium ions on sea urchin embryos: comparison among phylogenetically distant species and focus on mechanisms regulating stress response and skeletogenesis.

Gadolinium (Gd) is a metal of the lanthanide series of the elements whose chelates are commonly employed as contrast agents for magnetic resonance imaging, and subsequently released into the aquatic environment. We investigated the consequences of sea urchin embryo exposure to sublethal Gd concentrations, comparing the effects on the development of four phylogenetically and geographically distant species: two Mediterranean species, Paracentrotus lividus and Arbacia lixula, and two species living in the East coast of Australia, Heliocidaris tuberculata and Centrostephanus rodgersii. Measures of the Gd content inside embryos by ICP-MS showed a time- and dose-dependent increase. In all these s…

Gadolinium-induced stress response causes a time-dependent miss-expression of regulative and structural genes involved in the development of the sea urchin P. lividus

Safety of hospital discharge before return of bowel function after elective colorectal surgery

Ileus is common after colorectal surgery and is associated with an increased risk of postoperative complications. Identifying features of normal bowel recovery and the appropriateness for hospital discharge is challenging. This study explored the safety of hospital discharge before the return of bowel function.A prospective, multicentre cohort study was undertaken across an international collaborative network. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The main outcome of interest was readmission to hospital within 30 days of surgery. The impact of discharge timing according to the return of bowel function was explored using multiva…

Asimmetric skeleton patterns induced by gadolinium ions in sea urchin embryos: focus on mechanisms regulating skeletogenesis and comparison among phylogenetically distant species

Particle tracking in a gap of aquatic vegetation meadow

Aquatic vegetation considerably affects the flow field in water bodies, with influence increasing as the depth decreases. As a consequence, vegetation also affects suspended particle transport. In inshore sandy beds less than 40 m deep of the Mediterranean Sea, meadows of Posidonia oceanica are widespread. This plant is constituted by a tuft of very thin and flexible ribbon-like leaves about 1 cm wide and up to 1.5 m long; the meadow areal density can reach 1000-1200 plant/m2. Frequently, such meadows are not continuous but vegetated areas alternate with sand strips (“gaps”). The presence of such discontinuities noticeably affects the flow field and gaps can actually act as particle traps. …

Trasporto di particelle sospese in una discontinuità di un prato di vegetazione acquatica

La vegetazione acquatica influenza sensibilmente il campo di moto e il trasporto solido nei corpi idrici. Nelle aree sottocosta del Mar Mediterraneo sono molto diffusi i prati di Posidonia oceanica, una pianta costituita da un ciuffo di foglie nastriformi molto lunghe e flessibili. Spesso i prati sono interrotti da frequenti strisce di sabbia, e tali discontinuità, modificando sensibilmente il campo di moto, possono agire come “trappole” per i sedimenti. Nella presente memoria, sulla base di un campo di moto sperimentale, si simula numericamente il trasporto di particelle sospese in una tale discontinuità. A tal fine si adotta un semplice modello lagrangiano che assume assenza di velocità r…

Effect of environmental stress on sea urchin embryos and larvae: from developmental to molecular biology analyses

Skeleton growth inhibition in sea urchin embryos Paracentrotus lividus after manganese exposure.

In the sea urchin embryos, skeleton is specified by interactions between PMCs and patterning cues derived from the ectoderm. PMCs use spatial and temporal information to organize the proper animal-vegetal and oral-aboral position and orientation of the two tri-radiate skeletal spicules. Many experiments have demonstrated that exposure to metals, such as lithium, zinc and nickel, can disrupt skeleton patterning information. Here, we have investigated the effects of manganese (Mn) on Paracentrotus lividus embryo development. We found that Mn exposure prevents skeleton growth producing spicule-lacking embryos. Normal skeleton growth was partially rescued after Mn removal from the culture. To d…

Toxicity induced by Gadolinium ions on sea urchin embryos: comparison among phylogenetically distant species and focus on stress response and skeletogenesis.

Pharmaceuticals are a class of emerging environmental contaminants. Gadolinium (Gd) is a lanthanide metal whose chelates are employed as contrast agents for magnetic resonance imaging, and subsequently released into the aquatic environment. We investigated the effects of exposure to sublethal Gd concentrations on the development of four phylogenetically and geographically distant sea urchin species: two Mediterranean, Paracentrotus lividus and Arbacia lixula, and two from Australia, Heliocidaris tuberculata and Centrostephanus rodgersii. Sensitivity to Gd greatly varied, with EC50 ranging from 56 nM to 132 µM across the four species. Measures of the Gd and Ca content inside embryos showed a…

Developmental abnormalities induced by Gadolinium causes a time-dependent miss-expression of regulative and structural genes in P. lividus sea urchin embryos

Gadolinium (Gd) is a metal of the lanthanide series of the elements whose chelates are commonly used as contrast agents for magnetic resonance imaging. Its release into the aquatic milieu has posed serious concerns regarding its noxious effects, and therefore Gd is now considered an emerging environmental pollutant. The sea urchin embryo is an excellent model used in both toxicological and developmental research. We analysed the consequences of embryo exposure to sublethal concentrations of Gd on embryo development, focusing on skeletogenesis and developmental symmetry. We observed a strong inhibition of skeleton growth, frequently displayed by an asymmetrical pattern. Continuous exposure t…