Argomenti di Patologia Comparata dei Molluschi - Aspetti ecologoci e sanitari.

Questo volume nasce con l’intento di colmare, anche se solo parzialmente, una lacuna che per quanto ci è noto, appare evidente nel contesto della bibliografia scientifica nazionale: la mancanza di testi di riferimento aggiornati, in lingua italiana, di patologia degli organismi acquatici. Tra questi, i molluschi rappresentano organismi modello sempre più considerati rispetto ad altri, sia per la loro importanza bio-medica ed ecologica che per quella socio-economica. Il testo è diretto non solo agli studenti dei corsi di laurea in discipline Biologiche e Veterinarie, ma anche ai professionisti (Biologi, Medici, Veterinari) che lavorano nei settori della Ricerca, della Sanità Pubblica, dell’Acquacoltura, dell’Ecologia. La Patologia comparata dei molluschi, nel contesto del volume, viene sempre trattata nell’ottica di una comprensione più generale del rapporto tra salute e ambiente, oggi aspetto imprescindibile della “filosofia” di fondo che caratterizza le linee guida della Unione Europea per lo sfruttamento sostenibile delle risorse biologiche acquatiche vive e l’ottimizzazione del contributo sostenibile dell’acquacoltura alla sicurezza alimentare. La struttura del libro prevede una prima parte di patologia generale comparata (vertebrati - invertebrati - molluschi) ed una seconda parte di patologia speciale che include una breve trattazione delle principali malattie batteriche, virali, parassitarie e micotiche dei molluschi nonché alcune note legislative redatte dal dott. Giuseppe Arcangeli, Responsabile del Laboratorio di Riferimento Nazionale per le malattie dei Molluschi all’Istituto Zooprofilattico Sperimentale delle Venezie

Preparazione di materiali nanostrutturati a base di Pt per applicazioni in catalisi

L’ossido di grafene (GO) è un materiale 2D prodotto dall'ossidazione della grafite dalle interessanti proprietà meccaniche. La presenza di gruppi funzionali ossigenati rende il GO fortemente idrofilo e quindi facilmente disperdibile in acqua. L’utilizzo del GO in catalisi è legato alla sua ottima capacità di disperdere la fase attiva, grazie all’elevata area superficiale e di favorire la stabilizzazione delle particelle metalliche. Inoltre, se trattato in condizioni riducenti, il GO recupera parzialmente le caratteristiche di conducibilità elettroniche tipiche dei materiali grafenici che possono essere sfruttate per favorire reazioni di ossidazione o riduzione. Lo scopo di questo lavoro di tesi ha quindi riguardato la sintesi e caratterizzazione di materiali nanostrutturati a base di Pt e GO da utilizzare in catalisi. In particolare, lo studio ha comportato la preparazione di questi sistemi attraverso l’eterocoagulazione e spray-freeze-granulation di sospensioni nanometriche di TiO2 e SiO2 a cui sono stati aggiunti l’ossido di grafene ed il precursore del Pt. Nel processo di eterocoagulazione ci si basa su un approccio di tipo self-assembling, che sfrutta l’attrazione tra superfici di carica opposta, per favorire l’organizzazione spontanea dei nanosol di partenza in strutture core-shell. Le sospensioni sono state poi granulate utilizzando un sistema di liofilizzazione spray che ha portato alla formazione di catalizzatori granulati nanostrutturati con dimensioni micrometriche. I materiali preparati sono stati poi testati nella reazione di riduzione del 5-idrossimetilfurfurale (HMF) a 2,5 bisidrossimetilfurano (BHMF)

Disease and Disorders of Freshwater Unionid Mussels: A Brief Overview of Recent Studies

The use of aquatic invertebrates in biomedical research and as environmental sentinels has dramatically grown in recent decades, with an increased need in understanding of comparative pathology. The Unionids freshwater mussels are a group of worldwide distributed bivalves residing small ditches and ponds, lakes, canals and rivers, often used as animal test in eco-toxicological studies. Once one of the most abundant bivalve molluscs in ancient rivers around the world, now many of them are declining in many countries and consequently are nearly extinct in many areas. The causes of this decline are not fully understood but alteration and degradation of the freshwater habitat seemed to play a central role. To date, link causality to the observed losses during episode of mussel die-offs has been more difficult to establish, and disease and pathogen presence have been scarcely considered. In this article we provide a brief overview of unionids freshwater mussel conservation status, also describing reported diseases and pathogens and illustrating a few relatively well-documented studies

Presence of Gambusia affinis (Baird & Girard, 1853) in a freshwater ecosystem of Campania region (Italy)

The western mosquitofish, Gambusia affinis, is a small fish native to the southeastern United States. In the past century this species, and its congener, the eastern mosquitofish, Gambusia holbrooki, have been stocked in permanent and temporary waters throughout the world for mosquito control. These two species, very similar in appearance and biology, quickly became invasive with a strong ecological impact on ecosystems. They are considered responsible for the decline of several native amphibians and small fish in the Mediterranean region. Previous studies on European population conducted from Portugal to Greece reported the presence of only G. holbrooki in Italy, with report on Sicily (Catania) and Tuscany (Coltano) (Vidal, 2010). During an experimental trawl survey in 2010, samples of mosquito fishes were collected with nets from a pond near Cancello Arnone (Campania, Caserta, Italy). In order to define the Gambusia species, identification through dichotomous keys and DNA based methods were conducted. In particular, gonopodia morphology of preserved male individuals along with dorsal and anal fin rays were used to species differentiation (Walters and Feeman, 2000; Veenvliet, 2007), in our case giving uncertain results. For the molecular characterization, DNA from muscle tissue was isolated and two primer sets were used based on the conserved regions of the 12S and 16S rRNA loci as described by Kitano et al. (2007). PCR amplification and sequencing showed a 100% of maximum identity with G. affinis sequences in Genbank. These results, while contributing to unriddle the ambiguities in Gambusia taxonomy (see Vidal, 2010), call for further studies in order to define Gambusia affinis distribution in the Campania region and its impact on freshwater population

Vibrio mediterranei, a Potential Emerging Pathogen of Marine Fauna: Investigation of pathogenicity using a bacterial challenge in Pinna nobilis and development of a species‐specific PCR

Aims Extreme mortality events affecting Pinna nobilis, some associated to Vibrio mediterranei, have depleted many populations of this bivalve. The objective of this study was to demonstrate pathogenicity of V. mediterranei in the host P. nobilis by performing a bacterial challenge in P. nobilis to understand if V. mediterranei has specific virulence in this host. To assist this objective, a secondary objective was to develop a species‐specific DNA diagnostic test. Methods and Results P. nobilis collected from local bays were used in a challenge experiment with V. mediterranei (strain IRTA18‐108). Virulence in the host background of P. nobilis was demonstrated at doses of 103 CFUs / animal. An alignment of published Vibrio spp. atpA sequences was used to design V. mediterranei ‐specific primers. Further, data mining of published literature and V. mediterranei genomes identified multiple virulence‐related genes (vir genes) from which specific primers were designed for PCR detection of selected genes. Conclusion V. mediterranei strain IRTA18‐108 is pathogenic in the host P. nobilis . The virulence genes sod, rtx , and mshA were identified in this strain. Temperatures of 24ºC or higher appear to trigger onset of virulence. Sensitivity and specificity of the Vm atpA PCR is useful for diagnosis of Vibriosis in shellfish. Significance and Impact of the Study The presence of previously described virulence genes have been confirmed in this strain. The specific Vm atpA PCR assay will aid management of future epizootics of this emerging pathogen of aquatic fauna, and improve surveillance capabilities for mortality events where Vibrios are suspect.info:eu-repo/semantics/acceptedVersio

Epidemiology of Noble Pen Shell (Pinna nobilis L. 1758) Mass Mortality Events in Adriatic Sea Is Characterised with Rapid Spreading and Acute Disease Progression

From May to October 2019, multiple mass mortality events (MMEs) of Pinna nobilis were observed along Croatian coastline starting from the south-east and rapidly progressing in north-western direction. Time dynamics of the MMEs closely followed general speed and direction patterns of surface sea-currents, advancing approximately 350 km in less than 3 months. Surveillance, clinical evaluation, and sample collection were performed on multiple sites with various degrees of mortality rates. Moribund P. nobilis individuals were collected and subjected to pathological, molecular, and microscopical investigation. Affected animals were positive for Mycobacterium in 70% of the individuals, and Haplosporidium pinnae was present in 58% of the cases. Observed pathological lesions were most severe where concurrent presence of both pathogens was confirmed (in 45.8% of moribund individuals). Moderate to strong lesions were observed in animals positive for Mycobacterium only (25% of cases), and lesions were absent or minor to moderate when only H. pinnae was confirmed (16% of cases). Considering the rapid and severe spread of the MMEs, the areas less exposed to major sea currents appeared to be at lower risk of pathogen transmission. Surveillance activities along the Croatian coastline identified several P. nobilis populations in such “lower risk” areas without apparent mortality or clinical symptoms. Such areas are of particular interest as source of potentially healthy individuals to support active recovery actions

Linking stocking densities and feeding strategies with social and individual stress responses on gilthead seabream (Sparus aurata)

Intensive aquaculture and poor management practices can cause stress and compromise welfare of farmed fish. This study aimed to assess the potential links between stocking densities and feeding methods with social and individual stress responses on juvenile seabream (Sparus aurata) through risk-taking and hypoxia tests. Seabream was first experimentally reared under two different densities: high (HD: 11-65 kg m−3) and low (LD: 3-15 kg m−3). After 120 days under these conditions, increment in fish weight was not affected by different stocking densities. HD seemed to induce a stronger schooling behavior on seabream juveniles seeking for the group safety during the risk test; while LD increased the mean number of movements per fish recorded and the time of first response. Additionally, HD conditions delayed the time of first response of proactive fish during hypoxia tests. Glucose levels were higher in reactive fish compared to proactive ones, being highly significant in fish reared at HD. In parallel, juvenile seabream was also experimentally reared for 106 days under two different feeding strategies: hand-feeding (HF) and self-demanding feeding (DF), which influenced fish growth and foraging behavior at group and individual level. HF method induced a positive effect on fish weight compared to DF systems. Time of first response during both hypoxia and risk-taking tests was shorter in HF fish than DF fish, and the mean number of movements per fish during risk-taking behavior tests was lower for DF fish compared to HF fish. No differences were found in glucose and cortisol concentrations between behavioral traits (proactive/reactive) and feeding strategies. Triggering actions of seabream in DF systems were also assessed, which seemed to be highly dependent on particular individuals and not related to proactive individuals. DF systems however reinforce the social hierarchy within the fish group, which might lead to a higher competitiveness for resources among fishes, increasing the social hierarchy, and therefore, the stress. The findings of this study provide valuable information to the industry for the management of fish stress and welfare under production conditions at social and individual level.info:eu-repo/semantics/acceptedVersio

Linking stocking densities and feeding strategies with social and individual stress responses on gilthead seabream (Sparus aurata)

Intensive aquaculture and poor management practices can cause stress and compromise welfare of farmed fish. This study aimed to assess the potential links between stocking densities and feeding methods with social and individual stress responses on juvenile seabream (Sparus aurata) through risk-taking and hypoxia testsPostprint (author's final draft

MicroRNA co-expression networks exhibit increased complexity in pancreatic ductal compared to Vater’s papilla adenocarcinoma

iRNA expression abnormalities in adenocarcinoma arising from pancreatic ductal system (PDAC) and Vater’s papilla (PVAC) could be associated with distinctive pathologic features and clinical cancer behaviours. Our previous miRNA expression profiling data on PDAC (n=9) and PVAC (n=4) were revaluated to define differences/ similarities in miRNA expression patterns. Afterwards, in order to uncover target genes and core signalling pathways regulated by specific miRNAs in these two tumour entities, miRNA interaction networks were wired for each tumour entity, and experimentally validated target genes underwent pathways enrichment analysis. One hundred and one miRNAs were altered, mainly over-expressed, in PDAC samples. Twenty-six miRNAs were deregulated in PVAC samples, where more miRNAs were down-expressed in tumours compared to normal tissues. Four miRNAs were significantly altered in both subgroups of patients, while 27 miRNAs were differentially expressed between PDAC and PVAC. Although miRNA interaction networks were more complex and dense in PDAC than in PVAC, pathways enrichment analysis uncovered a functional overlapping between PDAC and PVAC. However, shared signalling events were influenced by different miRNA and/or genes in the two tumour entities. Overall, specific miRNA expression patterns were involved in the regulation of a limited core signalling pathways in the biology landscape of PDAC and PVAC

Nanomedicine Approaches for the Pulmonary Treatment of Cystic Fibrosis

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