411 research outputs found

    Comparative study of the effects of Montanide‚ĄĘ ISA 763A VG and ISA 763B VG adjuvants on the immune response against Streptococcus agalactiae in Nile tilapia (Oreochromis niloticus)

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    Acknowledgements We are highly grateful to thank Seppic, France, for providing us with the commercial products of MontanideTM ISA 763A VG and MontanideTM 437 ISA 763B VG. Funding This research project was financially supported by Mahasarakham University (Grant No. 6517022Peer reviewedPostprin

    Sex-related responses of blue mussels to the plasticiser DEHP under climate change scenarios

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    Climate change and plastic pollution are both pressing environmental issues. Little is known, however, about the combined effect of climate change conditions (such as global warming and ocean acidification) and plastic contaminants (such as the additive di-2-ethylhexyl phthalate DEHP), and whether this effect differs by sex. In fact, sex and gametogenesis status of individuals can influence a vast array of biological responses of several species, including the commercially important blue mussel Mytilus spp.This thesis investigates the consequences of DEHP exposure at environmentally relevant concentrations, alone or in combination with end-of-the-century simulated climate change conditions. A general effect of DEHP on mussel reproductive traits was observed, which confirmed the endocrine disruptive nature of this plasticiser. Specifically, fertility outcomes and estrogen receptor-related pathways were affected by the exposure, especially in female individuals. Overall, when combined with increased temperature or lowered pH, DEHP affected histological, molecular, transcriptomic, metabolic and behavioural systems at various degrees. Furthermore, as it was previously noted for other endocrine disruptive chemicals, the additive DEHP seemed to display a non-monotonic dose-response curve, provoking a stronger effect at low concentrations than at higher levels. Climate change stressors were also noticed to elicit a response in exposed individuals, especially increased temperature on spawning events and lowered pH on valve behaviours. Finally, when analysing the gene expression outcomes, sex and gametogenesis stage were considered useful predictive factors for interpreting the molecular datasets

    Renibacterium salmoninarum and Aeromonas salmonicida pathogenesis and virulence in lumpfish (Cyclopterus lumpus)

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    Renibacterium salmoninarum, the etiological agent of Bacterial Kidney Disease (BKD), and Aeromonas salmonicida, which causes furunculosis, are economically important pathogens of marine fish. The marine teleost lumpfish (Cyclopterus lumpus) is an eco-friendly cleaner fish in Atlantic salmon (Salmo salar) farming. As the lumpfish demand in salmonid aquaculture continues to rise, understanding how lumpfish interact with well-known Gram-positive and Gram-negative fish pathogens is certainly required. Therefore, in my Ph.D. thesis, I studied the interactions between lumpfish host and Grampositive R. salmoninarum or Gram-negative A. salmonicida with a particular focus on the fundamental aspects of bacterial pathogenicity and virulence. First, I evaluated the lumpfish susceptibility and immune response to R. salmoninarum infection. Lumpfish showed typical BKD clinical signs and 35 % mortality when infected with a high dose of R. salmoninarum (1√ó109 cells dose-1). High bacterial loads were observed in tissues (i.e., spleen, liver, and head kidney) at 28 days post-infection (dpi), and R. salmoninarum continued to persist in tissues until 98 dpi. Further, gene expression analysis using qPCR in the fish head kidney found that R. salmoninarum causes immune suppression at 28 dpi and lumpfish induce a cell-mediated immune response at 98 dpi. Second, I profiled the lumpfish head kidney transcriptome response to R. salmoninarum at early (28 dpi) and chronic (98 dpi) infection using RNA sequencing. Compared to 98 dpi, lumpfish induced many molecular pathways and genes at 28 dpi. For instance, R. salmoninarum-induced genes at 28 dpi were linked to innate and adaptive immunity, while R. salmoninarum-suppressed genes were involved in amino acid metabolism, cellular and developmental processes. In contrast, the transcriptome response of the lumpfish head kidney to this pathogen was minimal at 98 dpi, with R. salmoninarumdependent dysregulation of genes primarily connected to cell-mediated adaptive immunity. Third, I described the riboflavin supply pathways of A. salmonicida. Using in silico tools and RT-PCR, I found that A. salmonicida has a riboflavin biosynthesis pathway (RBP) and a riboflavin transporter. Moreover, I constructed the deletion mutants of riboflavin biosynthesis genes, their duplicated copies, and the transporter (ribN) of A. salmonicida and studied their role in virulence and potential as live-attenuated vaccine candidates using the lumpfish infection model. The results showed that riboflavin biosynthesis is crucial for A. salmonicida virulence. Overall, the thesis provided fundamental insights into the pathogenicity and virulence of R. salmoninarum and A. salmonicida and lumpfish response. The findings presented here are valuable for developing immunoprophylactic measures for lumpfish against BKD and furunculosis

    From invasion to fish fodder: inclusion of the brown algae rugulopteryx okamurae in aquafeeds for european sea bass dicentrarchus labrax (L., 1758)

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    In keeping with the premises of Blue Circular Economy in the European Union, the present study explored the possibility of using the invasive brown alga Rugulopteryx okamurae in aquafeeds for European sea bass (Dicen-trarchus labrax). Assuming the raw algae biomass could negatively impact animal performance, four experi-mental formulations were prepared, by including macroalgae material at 5%, using crude (CR), enzymatically hydrolysed and fermented (EF), enzymatically hydrolysed (E), or fermented (F) R. okamurae biomass, which we tested against a control feed (CT). To evaluate the effects of the experimental diets, besides animal growth performance and biometric parameters, we devised a toolbox focused on the intestine and intestinal function: i) ex-vivo epithelial resistance and permeability in Ussing chambers; ii) microbiota composition through NGS; iii) expression profiles of selected markers for epithelial integrity, transport, metabolism, and immune response, by qPCR. Our results show differentiated allometric growth among diets, coupled with intestinal epithelium al-terations in permeability, integrity, and amino acid transport. Additionally, evidence of microbiota dysbiosis and contrasting immune responses between experimental diets, i.e. pro-inflammatory vs. anti-inflammatory, are also described. In conclusion, we believe that R. okamurae could be a suitable resource for aquafeeds for the European sea bass, although its use requires a pre-treatment before inclusion. Otherwise, while the fish still have a positive growth performance, the gastrointestinal tract pays a toll on the integrity, transport, and inflammatory processes.LA/P/0101/2020info:eu-repo/semantics/publishedVersio

    Functional and molecular mmune response of rainbow trout (Oncorhynchus mykiss) following challenge with Yersinia ruckeri

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    Currently, aquaculture production of rainbow trout (Oncorhynchus mykiss) is a multibillion dollar industry; nevertheless, the development of this sector has not been exempt from pitfalls related to the recurrent presence of pathogens of bacterial origin. This is the case of Yersinia ruckeri, the etiologic agent of the infectious pathology known as Enteric Red Mouth Disease (ERM), causing serious economic losses that can be as high as 30‚Äď70% of production. Although several studies have been performed regarding pathogen features and virulence factors, more information is needed about the host defense mechanism activation after infection. Given this perspective, this study aimed to evaluate rainbow trout‚Äôs short-term innate immune response against infection with Y. ruckeri. A series of factors linked to the innate immune response were evaluated, including determination of hematological parameters, oxidative stress biomarkers, and analysis of the expression of immunerelated genes. Results showed a significant decrease in several hematological parameters (white blood cell count, hematocrit, neutrophils, monocytes, lymphocytes, and thrombocytes) and oxidative stress indicators (SOD) between the control and infected groups. In addition, there were significant differences in the level of gene expression between infected individuals and the control group. Most of these genes (il-1b, il-8, il-10, tnf-a1, tnf-a2, socs3, mmp-9, cath, hsp-70, saa, fer, pcb) were upregulated within the first 24 h following infection. Results from this study showed more insights into the short-term immune response of rainbow trout to infection with Y. ruckeri, which may be useful for the establishment of biomarkers that may be used for the early detection of ERM.info:eu-repo/semantics/publishedVersio

    Macrophage: A Key Player of Teleost Immune System

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    Fish, the free-living organisms, residing in aquatic environment, are earliest vertebrates with fully developed innate and adaptive immunity. Immune organs homologous to those of mammalian immune system are found in fish. Macrophages are best known for their role in immunity, basic function of which being cytokine production and phagocytosis. Due to environmental adaptation and whole genome duplication, macrophages in teleost are differently modulated (pro-inflammatory, M1-type, and anti-inflammatory/regulatory, M2-type) and perform a variety of different functions as compared with those of mammals. Phagocytosis is a major mechanism for removing pathogens and/or foreign particles in immune system and therefore is a critical component of the innate and adaptive immune system. One of the most competent phagocytes in teleost is found to be macrophages/monocytes. Increasing experimental evidence demonstrates that teleost phagocytic cells can recognize and destroy antigens to elicit adaptive immune responses that involve multiple cytokines. A detail understanding of teleost macrophages and phagocytosis would not only help in understanding the immune mechanism but will also help in disease prevention in teleost

    Characterizing toxicity pathways of fluoxetine to predict adverse outcomes in adult fathead minnows (Pimephales promelas)

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    Current ecotoxicity testing programs mandated by regulatory agencies are impeded as they predominantly rely on slow and expensive animal tests measuring traditional adverse outcomes such as mortality, growth, disease, reproductive failure, or developmental dysfunction. To address these concerns and support environmental risk assessment, the development of new approach methodologies (NAMs) is increasingly involving short-term mechanistic assays that employ molecular endpoints, such as transcriptomics and proteomics, to predict adverse outcomes of regulatory relevance. The research in this thesis aimed to use fluoxetine (FLX) as the model compound for the development of a novel mechanism-based toxicity assay through elucidation of its molecular toxicity pathways in adult fathead minnows. Specifically, the objectives of this study were to characterize the relationships between molecular response patterns using whole proteomics and transcriptomics and apical level effects of regulatory relevance (fecundity and histopathology). In two parallel studies, fish were exposed to three FLX concentrations (measured: 2.42, 10.7, and 56.7 ¬ĶgL-1) and a control. After the 96-hour exposure, molecular response signatures were characterized using whole proteomics and transcriptomics analyses in livers and brains of exposed male fish. Following the 21-day exposure, fish were sampled and assessed for liver histopathology and morphometric measurements. Fecundity was monitored throughout the study and revealed a significant reduction at all FLX-treatment levels. Hepatic histopathological assessment found presence of lipid-type vacuolation in two of five specimens of fish exposed to 56.7 ¬ĶgL-1 FLX. Whole transcriptomic analysis in the liver revealed dysregulation of pathways associated with biosynthesis and metabolism of fatty acids, which may be an upstream molecular response that led to lipid-type vacuolation of hepatocytes, as observed in the histology analysis. Whole proteome analysis of the same fish revealed dysregulation of several processes including PPAR signalling. These molecular signatures may be upstream responses that led to lipid-type vacuolation of hepatocytes. Upregulated genes in the brain suggested alterations in serotonin-related signalling processes and reproductive behaviour, which may explain the observed significant decrease in fecundity. While the relationships between molecular responses and adverse outcomes remain complex, this research provided important insights into the mechanistic toxicity of FLX. This work achieved the research objectives in demonstrating the potential of large-scale omics data to elucidate the complex physiological response of adult fathead minnows to FLX as well as added to the growing body of literature on the utility of these methods in support of chemical hazard assessment

    The contributions of the MUNA network to CUCS Naples 2022. Proceedings of the MUNA sessions

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    [Italiano]: Il Consortium Muna (Mediterranean and Middle East University Network Agreement) è stato fondato nel 2015 e rinnovato nel 2021, quando 30 Università provenienti da tutti i Paesi dell'area mediterranea e alcune altre dal Medio Oriente hanno firmato l'Accordo Quadro. Come scritto nell'Accordo Quadro, anche in questo spazio Muna della Conferenza CUCS, proponiamo tre diversi temi principali: MARE NOSTRUM (il nostro Mare, il Mediterraneo), PERSONA (l'Uomo) e ORBIS (la Terra), per riassumere le proposte di Cooperazione tra le Università di Muna Network. La prima sessione è dedicata al campo di ORBIS per condividere la sostenibilità, attraverso la biodiversità come elemento chiave per lo sviluppo del suolo in diversi aspetti come la gestione sostenibile dell'agricoltura, della fauna e della flora, con impatto nel campo della veterinaria. Tuttavia, un focus è anche legato all'inclusione e all'integrazione nelle città sostenibili in questo periodo di pandemia e flussi migratori rispetto al problema dei cambiamenti climatici nell'area mediterranea. La seconda sessione è incentrata su PERSONA, per condividere le esperienze nell'immunodeficienza primaria innata con i contributi di diverse Università di diverse aree del Mediterraneo, esaminando approcci di prevenzione e cura, anche attraverso la proposta di uno studio comparativo. Vengono discusse le differenze culturali in questo periodo di pandemia e la situazione dei diritti umani nel bacino mediterraneo. L'ultimo punto è MARE NOSTRUM, incentrato sullo sfruttamento delle risorse mediterranee proposto dalle Cooperazione Internazionale tra Muna Partners. Oltre allo sfruttamento, vengono ulteriormente sviluppati i temi del miglioramento della qualità dell'acqua, della salvaguardia del settore ittico e dell'obbligatoria migliore organizzazione delle aree portuali. In conclusione, una tavola rotonda discute le opportunità della Cooperazione, soprattutto per capire quali proposte possono essere seguite nella Cooperazione Universitaria e magari per definire progetti futuri./[English]: The Muna Consortium (Mediterranean and Middle East University Network Agreement) was founded in 2015 and renewed in 2021, when 30 Uni¬versities coming from all Countries of Mediterranean area and some others from Middle East signed the Fra¬mework Agreement. As written in the Framework Agreement, also in this Muna space in the CUCS Conference, we propo¬se three different main themes: MARE NOSTRUM (our Sea, the Mediterranean), PERSONA (Man) and ORBIS (the Earth), to summarize the proposals of Co¬operation between Muna Network Universities. The first session is dedicated to the field of ORBIS to share the sustainability, through the biodiversity as a key ele¬ment for the development of soil in different aspects as agricolture, fauna and flora sustainable management, with impact in the field of veterinary. Neverthless, a focus is also related to the inclusion and integration in the sustainable cities during this time of pandemia and migration flows with regard to the problem of clima changes in the Mediterranean area. The second session is focused on PERSONA, to share the experiences in the primary immunodefi¬ciency inborn with the contributions of different Uni¬versities of different mediterranean area, examinating approaches of prevention and treatment, also thorough the proposal of a comparative study. Culture differencies in this pandemia period and the situation of human rights in the medi¬terranean basin are discussed. The last item is MARE NOSTRUM, foused on exploitation of the Mediterannean resources proposed by International Cooperations among Muna Partners. Besides the exploitation, the the¬mes of improving the quality of water, the safe¬guarding of ittic sector and the mandatory better organization of port areas are further developed. In conclusion, a round table discusses the oppor¬tunities of the Cooperation, especially to understand which proposals can be followed in the Universities Cooperation and maybe to establish future projects

    ¬ęIo vivo fra le cose e invento, come posso, il modo di nominarle¬Ľ

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    This study‚Äôs aim is to deepen and enhance the linguistic dimension in Pier Paolo Pasolini's work, in the hope of restoring to his figure all the fullness of his intense and visceral relationship with the entire universe of languages. In the first part of the work we will investigate the various moments of Pasolini‚Äôs reflection on different expressive codes, from dialect to the language of cinema, from the 'Language of Reality' to the technological neo-Italian, promptly counterposed by the author‚Äôs linguistic experimentation. From here a broad lexical investigation starts - this study being the subject of the second part of this volume ‚Äď with the aim of highlighting the author‚Äôs contribution to contemporary Italian (as to this day many 'keywords' from Pasolini‚Äôs universe still echo in Italian language, from ¬ęnuovo Potere¬Ľ to ¬ęPalazzo¬Ľ, from ¬ęomologazione¬Ľ to ¬ęmutazione antropologica¬Ľ), thus confirming, once again, the inseparable relationship between reflection and language creativity, giving birth to a new, unique portrait of Pasolini as a 'linguist' and at the same time as an 'onomaturgist'
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