Due to their unique properties, perfluorinated substances (PFAS) are widely used in multiple industrial and commercial applications, but they are toxic for animals, humans included. This review presents some available data on the PFAS environmental distribution in the world, and in particular in Europe and in the Veneto region of Italy, where it has become a serious problem for human health. The consumption of contaminated food and drinking water is considered one of the major source of exposure for humans. Worldwide epidemiological studies report the negative effects that PFAS have on human health, due to environmental pollution, including infertility, steroid hormone perturbation, thyroid, liver and kidney disorders, and metabolic disfunctions. In vitro and in vivo researches correlated PFAS exposure to oxidative stress effects (in mammals as well as in other vertebrates of human interest), produced by a PFAS-induced increase of reactive oxygen species formation. The cellular antioxidant defense system is activated by PFAS, but it is only partially able to avoid the oxidative damage to biomolecules.

The production of reactive oxygen species (ROS) is a normal consequence of the aerobic cell metabolism. Despite their high and potentially detrimental reactivity with various biomolecules, the endogenous production of ROS is a vital part of physiological, immunological, and molecular processes that contribute to fitness. The role of ROS in host–parasite interactions is frequently defined by their contribution to innate immunity as effectors, promoting parasite death during infections. In vertebrates, ROS and antioxidant system enzymes, such as superoxide dismutase (SOD) are also involved in acquired immune memory, where they are responsible for T-cell signalling, activation, proliferation, and viability. Based on recent findings, ROS are now also assumed to play a role in immune priming, i.e., a form of memory in invertebrates. In this study, the potential involvement of Cu,Zn SODs in immunity of the red flour beetle Tribolium castaneum is described for the first time, applying an approach that combines an in silico gene characterisation with an in vivo immune priming experiment using the Gram-positive entomopathogen Bacillus thuringiensis. We identified an unusually high number of three different transcripts for extracellular SOD and found that priming leads to a fine-tuned modulation of SOD expression, highlighting the potential of physiological co-adaptations for immune phenotypes.

In the present study, we describe the purification and molecular characterization of Cu,Zn superoxide dismutase (SOD) from Chionodraco hamatus, an Antarctic teleost widely distributed in many areas of the Ross Sea that plays a pivotal role in the Antarctic food chain. The primary sequence was obtained using biochemical and molecular biology approaches and compared with Cu,Zn SODs from other organisms. Multiple sequence alignment using the amino acid sequence revealed that Cu,Zn SOD showed considerable sequence similarity with its orthologues from various vertebrate species, but also some specific substitutions directly linked to cold adaptation. Phylogenetic analyses presented the monophyletic status of Antartic Teleostei among the Perciformes, confirming the erratic differentiation of these proteins and concurring with the theory of the “unclock-like” behavior of Cu,Zn SOD evolution. Expression of C. hamatus Cu,Zn SOD at both the mRNA and protein levels were analyzed in various tissues, highlighting the regulation of gene expression related to environmental stress conditions and also animal physiology. The data presented are the first on the antioxidant enzymes of a fish belonging to the Channichthyidae family and represent an important starting point in understanding the antioxidant systems of these organisms that are subject to constant risk of oxidative stress.

The present work consists in an experimental research based on teaching and learning Biology in primary school. The aims of this research are two. First, it wants to support the current scientific evidence that underlines the effectiveness of laboratory didactics. Secondly, it aims to prove that this method makes it possible to deal with several topics which are not currently mentioned in the Italian Guidelines. Nowadays, scientific evidence demonstrates that laboratory didactics has a stronger impact on lifelong learning than traditional didactic approaches, based on frontal lessons only. The epistemological and methodological structure is clear: Science, especially Biology, should not just be taught for their products (concepts, theories, innovations,) but also, and especially, for their processes. Therefore, laboratory activities, conducted through experimental methods, represent one of the best resources in order to develop problem-solving skills, which underline a scientific mind. In the laboratory, every question or curiosity opens to new discoveries. In this way students gradually come to formalize their scientific knowledge. The teacher's role is to suspend his immediate explanation. He should be able to support spontaneous questions by students and the possibility to make hypothesis based on their naive theories. Starting from children's curiosity, it also makes possible to consider aspects that really intrigue them but which are usually omitted by school programs, as they are considered too "far" from pupils' actual cognitive ability. Children, unlike adults, do not tend to take anything for granted and are fascinated and intrigued by everything is around them, regardless of its hypothetical complexity. For this reason, teaching Biology in this way means to support students' intrinsic motivation, giving them not only scientific notions, but also concrete answers with practical implications in their daily lives. In this research, we followed children's interest for the microscopic world and we treated microbiology and its biotechnological applications in food industry. We started from bread and yogurt productions, which are very close to students' reality, in order to introduce the topic of biotechnological applications using yeast (Saccharomyces cerevisiae) and bacteria (Streptococcus termophilus and Lactobacillus bulgaricus). It was surprising for children to "discover" that the dough of a bakery product or a dairy product is actually a living material. As a matter of fact, the billion cells of living microorganisms, the yeasts and the bacteria, are in fact the protagonists of fermentation processes. In conclusion, considering the outcomes of our research, it is clear that the educational implications of laboratory didactics are very significant and therefore not negligible. Moreover, this work would be an exhortation to teachers to use this method and to become a potential changing agent.

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