Acetylcholinesterase (AChE) is a key enzyme in the nervous system. It terminates nerve impulses by catalysing the hydrolysis of neurotransmitter acetylcholine. As a specific molecular target of organophosphate and carbamate pesticides, acetylcholinesterase activity and its inhibition has been early recognized to be a human biological marker of pesticide poisoning. Measurement of AChE inhibition has been increasingly used in the last two decades as a biomarker of effect on nervous system following exposure to organophosphate and carbamate pesticides in occupational and environmental medicine. The success of this biomarker arises from the fact that it meets a number of characteristics necessary for the successful application of a biological response as biomarker in human biomonitoring: the response is easy to measure, it shows a dose-dependent behavior to pollutant exposure, it is sensitive, and it exhibits a link to health adverse effects. The aim of this work is to review and discuss the recent findings about acetylcholinesterase, including its sensitivity to other pollutants and the expression of different splice variants. These insights open new perspective for the future use of this biomarker in environmental and occupational human health monitoring.

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The aim of this work was to assess the diffusive properties of poly(ethylene glycol) diacrylate (PEGDA)‐based hydrogels, derived from low MW prepolymers, in view of potential biomedical applications. Several hydrogels were synthesized through UV irradiation of PEGDA solutions for different exposure times. Swelling measurements in distilled water were performed to estimate the yielded crosslink density, while swelling tests at 37 °C in selected media allowed to analyze the mesh size changes induced by various pH and ionic strength (IonS) conditions. The transport of glucose and insulin through thin hydrogel membranes was finally assessed in a modified Ussing chamber at physiological values of pH and IonS (7.4 and 150 mM, respectively). Results showed that the swelling was dependent on the IonS (with swelling reductions up to 20–30% for IonS increases in the range 0–300 mM) and, to a lesser extent, on the pH of the surrounding medium (with swelling increments of about 10% for increasing pH in the range 2.5–11). All hydrogels were also permeable to glucose and insulin, which displayed comparable diffusion coefficients (in the order of 10−6 cm2/s). Specific interactions between glucose and the polymer chains were evidenced by values of the partition coefficient higher than unity. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44380.

Observational data suggest that the white seabream Diplodus sargus, a sparid fish of economic and ecological relevance in the Mediterranean Sea, has included the invasive green alga Caulerpa racemosa in its diet. Here we adopted a chemoecological approach to study the trophic relationship between the fish and the exotic pest. We demonstrated that the red pigment caulerpin, the most abundant secondary metabolite of C. racemosa, enters food chains and accumulates in the fish tissues. General biological condition markers associated with fish health and reproductive development were measured and correlated with the caulerpin levels in the fish tissues. Significant correlations among caulerpin tissue load (determined by liquid chromatography-mass spectrometry analysis) and fish condition factor and hepatosomatic index were obtained, suggesting a possible detrimental effect of the dietary exposure to C. racemosa on D. sargus. Glutathione peroxidase and catalase activity were also significantly correlated with caulerpin concentrations in the liver, suggesting a possible interaction between algal metabolites and liver antioxidant mechanisms. Studies on the impact of invasive macroalgae on marine assemblages have been almost exclusively focused on the structural modification of benthic assemblages, through the alteration of the relative importance of some endemic species and the modification of habitat complexity. Here we propose a new mechanism by which invasive algae can impact marine systems, namely the entry of pest metabolites in food webs, with potential detrimental effects on the population dynamics of a single species, alteration of trophic webs and changes in the functioning of coastal ecosystems.

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