Strategy proposal using QSAR models to approach mutagenicity assessment of non intentionally added substances in recycled plastic resins.

Context: Transition to the use of recycled plastics raises an issue concerning safety assessment of Non Intentionally Added Substances (NIAS). To assess the mutagenic potential of the recycled polyethylene impurities and to evaluate the need to perform in vitro assays on recycled resins, this study lies in identifying existing NIAS associated with recycled Low/High Density Polyethylene and assessing the mutagenicity data-gaps by employing in silico tools.

Methods: Quantitative Structure-Activity Relationship (QSAR) models predicting Ames mutagenicity were selected from literature, then NIAS were run to 1/evaluate performances of each model, 2/apply a QSAR strategy on the NIAS molecular space and address data-gaps.

Real-world data meta-analysis: procedural success and clinical outcomes after radiofrequency ablation of atrial fibrillation in South America.

Objective: To profile patients' characteristics, in-hospital results, and recurrence rates after radiofrequency ablation of atrial fibrillation (RAAF) in South America.

Methods: We comprehensively searched for single-center studies from South America with ≥10 patients receiving RAAF, published or presented from January 1, 2010, through June 29, 2020, excluding those reports aimed to specific populations such as permanent atrial fibrillation, structural cardiopathies, or re-do procedures.

Results: Main pooled estimates from a random-effects meta-analysis that included 3909 patients from 27 cohorts (from 5 countries): a) Patients characteristics: age 57.

New approach for hair keratin characterization: Use of the confocal Raman spectroscopy to assess the effect of thermal stress on human hair fibre.

Objective: The objective of our research was to investigate the heat-protecting effect of a product ex vivo and in vivo on human hair fibres.

Methods: A preparatory study was carried out in order to determine an optimal threshold of thermal stress. For this, the structure of cross-sections of the hair fibre was observed by optical microscopy.

Influence of applied quantity, water-immersion and air-drying on covering and microstructure of physical sunscreen films.

The features of topically applied suncream films depend on the applied quantities and could be modified by water immersion and air drying. The aim of this study was to investigate the effects of the aforementioned factors on physical sunscreen films and to establish the correlation between the in vitro determined Sun Protection Factor (SPF) and the microstructure of the mineral coating. The assessments were conducted by using UV spectroscopy and electron microscopy on sunscreen films applied on both synthetic membranes and human skin.

Epidermal reconstructs: a new tool to study topical and systemic photoprotective molecules.

In this study, we compared the effects of sunscreens and antioxidants on reconstructed epidermis made with or without melanocytes 24 h after UVB, UVA or UVA+B irradiation. For this purpose, we studied sunburn cells and cyclobutane pyrimidine dimer formation, protein and lipid oxidation, catalase and superoxide dismutase activities and vitamin E levels. Topical sunscreens protected against direct cell death and thymine dimer formation whereas their protective effect against protein and lipid oxidation and antioxidant depletion was less marked partly due to the difficulty of spreading the cream.