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Nel presente lavoro vengono presentati e discussi i risultati delle indagini necroscopiche, parassitologiche, microbiologiche, istopatologiche, immunoistochimiche, di immunofluorescenza indiretta (IFI), biomolecolari (RT-PCR) e sierologiche condotte su 8 esemplari (1 maschio neonato, 1 femmina subadulta, 5 femmine ed 1 maschio adulti) di stenella striata (Stenella coeruleoalba) rinvenuti spiaggiati nel periodo Agosto-Novembre 2007 in provincia di Imperia. Una polmonite (bronco-interstiziale) era evidente in 6 stenelle, con presenza di numerosi corpi parassitari in sede sia polmonare, sia extra-polmonare. Una meningo-encefalite subacuto-cronica multifocale non purulenta si osservava altresì in 4 animali (1 maschio e 3 femmine adulte), in cui erano istologicamente apprezzabili più o meno spessi manicotti perivasali di cellule infiammatorie mononucleate, con contestuali aggregati macrofagici in sede peri-paravasale. Lievi infiltrati linfo-plasmacellulari erano presenti a livello dei plessi corioidei, mentre moderate espressioni di sofferenza interessavano isolati o alcuni gruppi di neuroni, senza che fosse possibile dimostrare la presenza di inclusioni virali né al loro interno, né all’interno di altri tipi cellulari. I sieri di 4 stenelle (1 neonato, 1 subadulto, 2 adulti) contenevano inoltre anticorpi neutralizzanti anti-Morbillivirus, ad un titolo compreso fra 1:10 e 1:40. Ciononostante, le indagini immunoistochimiche, in IFI ed in RT-PCR per Morbillivirus hanno avuto esito negativo in tutti gli animali. In conclusione, si ritiene che ad una o più noxae diverse dal Morbillivirus sia verosimilmente da ascrivere l’eziologia primaria degli episodi di mortalità in questione. Ulteriori indagini sono comunque necessarie per confermare tale ipotesi.

Present study was aimed at investigating whether Morbillivirus infection is present in stranded dolphins from West Ligurian Sea. From obtained data, it seems more than realistic to believe that a morbilliviral agent took place in at least 4 out of the 8 dolphin analysed. Nevertheless, despite their seropositivity, IIIC, IIF and TR-PCR investigations yealded negative results in all cetaceans. In conclusion, data obtained from the study suggest that, albeit exposure to a morbilliviral agent was documented in half of the animals, one or more factors other that Morbillivirus could have involved in animals' death.

The impact of morbillivirus on cetacean is well known since a long time. Indeed, since 1987, at least eight morbillivirus infection (MI) epidemics have caused mass mortality of several free-living pinniped and cetacean populations around the world. At post-mortem examination, a commonly occurring macroscopic lesion is represented by more or less severe bilateral pneumonia, with consolidation, congestion and oedema of both lungs, which fail to collapse. Among the still debated, or even controversial issues regarding MI in sea mammals, the one related to the origin of their causative agents is of particular concern. It has recently also debated if some episodes ascribed to MI were real morbillivirus infections, as serological or immunohistochemical techniques failed to identify the virus. Another intriguing issue regards the synergistic effects, if any, associated with chronic exposure to a number of environmental pollutants, such as organochlorines and heavy metals. In fact, it is also unknown whether and how these chemicals contribute towards modulating the pathogenic and pathogenetic activity primarily displayed by sea mammal morbilliviruses. Among others, heavy metals have proved to act as immunomodulators in many mammals species, mainly acting as immunosuprressor. In present study we report about heavy metals (Cd, Pb and Hg) concentration in liver and muscle of stranded dead stripped dolphin (n= 9) from Tirrenian Sea collected during a suspected MI episode. Sampled cohort included a 5 days old calf, two sub-adult and 6 adult subjects. Contemporarily, autoptic lesions were recorded and a serological survey was conducted on brain samples of 8 out of 9 animals in order to verify if the causative agent of death was morbillivirus. Any possible correlation with immunosuppressive action of metals was also tested, even if low number of animals did not allow any statistical analysis. Obtained results showed mean metals concentration reported in table 1. Lowest levels of all metals were observed in the calf, but it should be noted that 10 out of 18 samples were below the limit of detection (LOD) for lead. These levels were always below the immunotoxic thresholds for cadmium and lead, while were always well below the threshold for mercury. Thus a certain degree of immunosuppression, including increase of apoptosis, reduction in lymphocyte proliferation and fagocytic activity, could be considered for all animals. Serological survey revealed that only 4 out of 8 animals analysed were positive to morbillivirus. Interestingly, positive animals presented no typical morbillivirus brain lesion, which were present in negative subjects. It should be noted the presence among sero-positive animals of the calf. In this case, a mother-calf antibody transfer with colostrum should be considered. Giovanni, qui ti sarei molto grata se potessi scrivere tu qualcosa sulla sierologia, tipo la questione del passaggio col colostro al cucciolo, la possibilità di un'immunità acquisita a seguito di esposizione "cronica" al virus, i dubbi sull'effettiva esposizione a morbillivirus o ad altri patogeni. Interestingly, when metal data were evaluated on the basis of serological results, higher levels of metal were found in sero-negative animals, as evident in hepatic lead and mercury Obtained data seems to suggest the occurrence of an infection different from morbillivirus, which induce cerebral lesions similar to MI and whose morbidity is increased by the action of mercury and probably of other contaminants known to act as immunosuppressive agents. Further and deeper researches are considered necessary in order to better define which is the role of pollutants in the severity of epidemics and, more important, which could be the real causative agent of the die-off of 2007 in Italy.

The electrochemical conversion of carbon dioxide is considered one of the most promising strategies to convert waste-CO2 into value-added chemicals. This review focuses on the synthesis of formic acid/formate in aqueous electrolyte using Sn-based cathodes; this material is considered relatively cheap and shows promising results in terms of faradaic efficiency. In order to be suitable at an industrial scale, the process should present simultaneously high current densities, faradaic efficiencies close to 100%, high concentrations of formic acid and long-term stability. Analysing the main results reported in the literature, it was observed that to date further studies are necessary to achieve this outcome. Several strategies that can be used to overcome the main bottlenecks of the process were presented and critically reviewed. Finally, to evaluate the main factors that affect the scalability of the process on an industrial scale, a technical-economic overview was discussed.