In silico prediction of the interaction of legacy and novel per- and poly-fluoroalkyl substances (PFAS) with selected human transporters and of their possible accumulation in the human body.

Per- and poly-fluorinated compounds constitute a wide group of fluorocarbon chemicals with widespread industrial applications, ranging from non-stick coating in cookware to water surfactants, from fire-fighting foams to water-repellent coatings on textiles. Presently, over 12,000 PFAS are known worldwide. In recent years, extensive research has focused on investigating the biological effects of these molecules on various organisms, including humans. Here, we conducted in silico simulations to examine the potential binding of a representative selection of PFAS to various human proteins known to be involved in chemical transportation and accumulation processes. Specifically, we targeted human serum albumin (HSA), transthyretin (TTR), thyroxine binding protein (TBG), fatty acid binding proteins (FABPs), organic anion transporters (OATs), aiming to assess the potential for bioaccumulation. Molecular docking simulations were employed for this purpose, supplemented by molecular dynamics (MD) simulations to account for protein flexibility, when necessary. Our findings indicate that so-called "legacy PFAS" such as PFOA or PFOS exhibit a higher propensity for interaction with the analysed human protein targets compared to newly formulated PFAS, characterised by higher branching and hydrophilicity, and possibly a higher accumulation in the human body.

A new cyclodextrin-grafted viscose loaded with aescin formulations for a cosmeto-textile approach to chronic venous insufficiency.

Cosmeto-textile applications can be used in the treatment of chronic venous insufficiency in legs by means of elastic bandages loaded with natural products which possess flebotonic properties. We have developed an efficient synthetic procedure for the preparation of ß-cyclodextrin (ß-CD)-grafted viscose by means of a 2-step ultrasound-assisted reaction. The highly grafted fabric bearing bis-urethane bridged ß-CD has been characterized by ATR-FTIR and CP-MAS spectra and by an empiric colorimetric method which used phenolphthalein as the CD guest. We have also developed a suitable cosmetic preparation containing natural substances and extracts (aescin, menthol, Centella asiatica and Ginkgo biloba) to recharge the CD-grafted textile. The efficacy of the new cosmeto-textile has been corroborated by in vitro studies of diffusion through membranes, cutaneous permeation and accumulation in porcine skin. Aescin was taken as a reference compound and its concentration in the different compartments was monitored by HPLC analysis. This cost effective cosmeto-textile shows excellent application compliance and is easily recharged and so has the strong base characteristics needed for possible industrial production.

In vitro tests to evaluate potential biological activity in natural substances.

The biological activity of polysaccharides from the mycelia of 40 Basidiomycetes was studied using an uncommon toxicity test technique, the planaria bioassay, and the better known potato disk bioassay. The results showed the utility of this duo of 'in vitro' tests as a preliminary screening of the toxicity of substances that are present in aqueous fungal extracts.

The characteristics of eye movements made during visual search with multi-element stimuli.

Saccadic eye movements during visual search made to detect a target embedded in a set of randomly distributed, identical elements have been measured. Both the time T1/2 taken to press a button to denote target detection (the manual response time) and the time Tf taken to fixate the target were determined. It is established that these two response times are closely related to each other, and have similar dependence on the number of reference elements N, both in search tasks for which T1/2 is independent of N (parallel search) and in those for which T1/2 is proportional to N (serial search). The properties of the eye movements made by two subjects in response to a variety of stimuli have been subjected to detailed analysis. It is shown that the number of fixations made during a given search is proportional to the manual response time T1/2 and that the probability of locating the target with a single fixation falls steeply as T1/2 increases. The latency of the first saccade is approximately linearly dependent on T1/2, and latencies made in performing a given task are distributed in a Gaussian manner the spread of the latency values increasing as the mean latency increases. It is conclude that the measurement of eye movements provides a more detailed description of visual search than that given by measurement of manual response times, and that in terms of eye movements, only a subset of those tasks for which T1/2 is independent of N can be classified as parallel.