7 research outputs found

    TOWARDS BENZ[A]ANTHRACENE XENOME ELUCIDATION IN PLANTS AND GREEN MICROALGAE

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    In only 12,000 years the Homo sapiens sapiens has completely modified the face of the Earth. The human pressure on the atmosphere, water and soil has been accelerate from the industrial revolution from which chemicals and energy have been released in the environment. Therefore, chemical environmental pollution and world climate changes are two of the main concerns that modern human must deal. Among chemicals released in the ecosystem the polycyclic aromatic hydrocarbon (PAHs) have gathered significant environment concerns for their detrimental biological effects, toxicity, mutagenicity, and carcinogenicity. The distribution of PAHs in the three environment compartments is related to the number of fused benzene rings. Two or three benzene rings have been occurring in the atmosphere whereas 5 or more rings are largely bounds in the soil particles. Intermediate, 4-rings, such as benz(a)anthracene (B[a]A) are partitioned between air and soil. The molecular mechanism involved to degrade PAHs into less toxic compounds by bacteria and fungi in soil has been elucidated. On the other hands, the metabolism of PAHs in plant and microalgae remain unknown. Signalling, transport, biotransformation of PAHs to less toxic molecules and compartmentalization are the main steps involved for their detoxification in photosynthetic cell. The expression of genes involved in these xenobiotics detoxification steps constitutes the xenome. The final aim of this work is to determine the B[a]A xenome in plants of tomato and in microalgae. So far, we have assessed the ability of tomato plants to grow in vitro and take up the B[a]A. Tomato seedlings were transplanted to MS medium added with 50 and 100 μg g -1 B[a]A and cultivated for 30 days. The detection of B[a]A in shoots infer a translocation from roots to shoots. However, the content of the PAH in shoots was much lower than in the root apparatus indicating that B[a]A was translocated very little from roots to shoots. The identification of microalgae species B[a]A capable of growing in presence of has been performed on 14 different species belonging to the genera Chlorella, Scenedesmus, Chlamydomonas, Ankistrodesmus, Botriococcus and Selenastrum, with six different concentrations of B[a]A. Four microalgae species showed a growth inhibition percentage less than 50% in a medium containing 43.8 μM B[a]A. The capacity to degrade B[a]A and affect the photosynthetic pigment content has been evaluated in the identified microalgae grown for 21 days in the medium containing B[a]A. The four microalgae strains reached 90% B[a]A degradation. Then, in silico analysis was carried out on C. reinhardtii proteome to identify potential laccase involved in the degradation process. Finally, the response of intracellular and extracellular activity in the absence and presence of the B[a]A was analysed by ABTS and 2,6-DMP assays

    A practical approach for the in vitro safety and efficacy assessment of an anti-ageing cosmetic cream enriched with functional compounds

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    (1) Background: Cosmeceuticals are topical products applied to human skin to prevent skin ageing and maintain a healthy skin appearance. Their effectiveness is closely linked to the compounds present in a final formulation. In this article, we propose a panel of in vitro tests to support the efficacy assessment of an anti-ageing cream enriched with functional compounds. (2) Methods: biocompatibility and the irritant effect were evaluated on reconstructed human epidermis (RHE) and corneal epithelium (HCE) 3D models. After a preliminary MTT assay, normal human dermal fibroblasts (NHDF) and keratinocytes (HaCaT) were used to evaluate the extracellular matrix (ECM) protein synthesis, and interleukin-6 (IL-6) and metalloproteinase-1 (MMP-1) production. (3) Results: data collected showed good biocompatibility and demonstrated the absence of the irritant effect in both 3D models. Therefore, we demonstrated a statistical increase in collagen and elastin productions in NHDF cells. In HaCaT cells, we highlighted an anti-inflammatory effect through a reduction in IL-6 levels in inflammatory stimulated conditions. Moreover, the reduction of MMP-1 production after UV-B radiation was demonstrated, showing significant photo-protection. (4) Conclusion: a multiple in vitro assays approach is proposed for the valid and practical assessment of the anti-ageing protection, anti-inflammatory and biocompatible claims that can be assigned to a cosmetic product containing functional compounds

    Pedagogical Practices for Virtual Worlds

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    As a result from activities carried out within Module 2 of the MUVEnation programme about exploring active learning approaches, we have created a collection of practices for teaching and learning in Virtual Worlds, organised in 21 chapters, classified in the following categories of instructional methods: Presentation, Demonstration, Discussion, Drill-and-practice, Tutorial, Cooperative Learning, Gaming, Simulation and Discovery. The educational professionals who participated in the course worked in teams, but in some cases individually to map and describe the existing range of teaching practices in Second Life, and to draw a reflection about the elements for their success. Practices described include: lecture, multimedia presentation, demonstration, dialogic teaching and specifically debates and consensus building, but also other forms of discussion like seminars, symposia, syndicates, panel discussion, workshops and organized forums; brain storming, treasure hunts and virtual quests, learning by projects, self paced learning and self study, Labs (class/ fields), role play, virtual theatre and theatrical improvisation matches, peer tutoring and learning, Role playing, and simulation games

    Educational Tools for Second Life: a handbook for educators in virtual worlds.

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    As a result of two collective activities organised during the MUVEnation programme, we have produced a collection of educational tools for Second Life. This collection has been produced in two stages. First, back in September 2008, 33 partcipants in the introductory module worked together in groups for the identification of more than 100 tools used for teaching and learning in Second Life. Later, in March 2009, 55 education professionals (lecturers, researchers, learning technologists and teachers) have collected, tested and fully described more than 150 tools. The result of this collective work has been transformed into a book, published as an Open Educational Resource under CC licence by attribution unported, so anyone is free to distribute without restrictions: adapt, translate, re-mix and improve it
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