278 research outputs found

    Estimating oxygen consumption of rainbow trout (Oncorhynchus mykiss) in a raceway: a precision fish farming approach

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    3openInternationalItalian coauthor/editorThe Precision Fish Farming (PFF) approach was applied to the estimation of fish oxygen consumption of rainbow trout in a raceway farm. A dynamic model, simulating the evolution of Dissolved Oxygen concentration, was identified: the daily oscillation of fish oxygen consumption rate was simulated by means of a sinusoidal function. The model was applied to the data set collected during a four-week field study, which was carried out in July 2019. Water temperature and Dissolved Oxygen concentration were measured with an hourly frequency in farm influent and effluent. Fish biomass was monitored on a daily basis by combining the data provided by a state-of-the art system for non-invasive estimation of fish weight distribution with mortality counting. The monitoring period was partitioned into two time-windows, as fish was not fed during the first two weeks. These windows were further partitioned into a calibration and validation set. Three model parameters, i.e. the average daily respiration rate, the amplitude of its daily oscillation, and its phase were estimated by fitting the model output to the time series of DO concentration in the effluent. The results of the calibration show that: 1) the daily average oxygen consumption rate is consistent with the literature; 2) the amplitude of the daily oscillation when fish is regularly fed is more than twice that estimated for fasting fish. The results of the validation suggest that the model could be used to implement a cost-effective automatic control of oxygen supply, based on the short-term prediction of oxygen demandopenRoyer, E.; Faccenda, F.; Pastres, R.Royer, E.; Faccenda, F.; Pastres, R

    Potential of shrimp waste meal and insect exuviae as sustainable sources of chitin for fish feeds.

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    Aquaculture is one of the world’s fastest growing food-producing sectors, providing more than half of all fish consumed globally for human nutrition. However, to maintain such growth and meet the increasing demand for aquatic food, sustainable raw materials for fish feeds are needed. In this regard, insects represent one of the most promising alternatives to fish meal (FM) protein source for use in aquafeeds. In addition to protein, insects contain bioactive compounds, such as chitin, which is a natural polysaccharide abundantly present in the pupal exuviae of some insects. Studies have shown that dietary chitin or its derivate chitosan acts as a prebiotic thus modulating the gut microbial communities of fish. Accordingly, the present study aimed to evaluate the effect of two waste products rich in chitin, i.e., shrimp head meal (SHM), and insect (Hermetia illucens) pupal exuviae on the gut microbiota of rainbow trout (Oncorhynchus mykiss). Three isoproteic, isolipidic, and isoenergetic diets containing either FM, SHD, or a combination of FM and 1.6% of pupal exuviae meal (PEM) were tested through a 91-day feeding trial. At the end of the experiment, no differences in final mean body weight, specific growth rate, and feed conversion ratio values were observed between fish experimental groups. Mortality was <1% and it did not correlate with diet for the entire duration of the trial. However, a modulatory effect of dietary pupal exuviae on fish gut microbiota was detected. Indeed, gut bacterial species richness improved by including insect exuviae. In particular, Firmicutes and Actinobacteria phyla, mainly represented by Bacillus, Facklamia, Brevibacterium, and Corynebacterium genera, were enriched in trout receiving pupal exuviae. These genera are chitinolytic and shortchain fatty acids (SCFAs)-producing bacteria. SCFAs production was confirmed by gas chromatography analysis, which detected the highest amount of butyrate in feces of trout fed with pupal exuviae meal. Functional inference analysis of intestinal microbiota using PICRUST metagenome prediction tool, showed differences in response to diet. In particular, eleven pathways were significantly different between control fish (FM) and fish fed the PEM diet, whereas twenty functional traits were significantly different between the FM and SHM fish groups. Overall, our data confirmed that chitin from insect’s pupal exuviae represents a promising functional ingredient, better than SHM, for positively modulating gut microbiota communities of rainbow trout

    Native larval parasitoids (Hymenoptera) of Frugivorous Tephritoidea (Kiptera) in South Pantanal, Brazil.

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    El objetivo de este estudio es evaluar la incidencia de los parasitoides (Hymenoptera) sobre larvara de tephritidae (moscas de la fruta) y los Lonchacidae frugivoros, en varias especies frutiferas nativas y exoticas en el Pantal sur Mato Grosso do Sul, Brasil. Noventa Y dos especies de frutas de 36 familias y 22 Ăłrdenes fueron evaluadas..

    Reduction of the ATPase inhibitory factor 1 (IF1) leads to visual impairment in vertebrates

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    In vertebrates, mitochondria are tightly preserved energy producing organelles, which sustain nervous system development and function. The understanding of proteins that regulate their homoeostasis in complex animals is therefore critical and doing so via means of systemic analysis pivotal to inform pathophysiological conditions associated with mitochondrial deficiency. With the goal to decipher the role of the ATPase inhibitory factor 1 (IF1) in brain development, we employed the zebrafish as elected model reporting that the Atpif1a−/− zebrafish mutant, pinotage (pnttq209), which lacks one of the two IF1 paralogous, exhibits visual impairment alongside increased apoptotic bodies and neuroinflammation in both brain and retina. This associates with increased processing of the dynamin-like GTPase optic atrophy 1 (OPA1), whose ablation is a direct cause of inherited optic atrophy. Defects in vision associated with the processing of OPA1 are specular in Atpif1−/− mice thus confirming a regulatory axis, which interlinks IF1 and OPA1 in the definition of mitochondrial fitness and specialised brain functions. This study unveils a functional relay between IF1 and OPA1 in central nervous system besides representing an example of how the zebrafish model could be harnessed to infer the activity of mitochondrial proteins during development

    Human Amniocytes Are Receptive to Chemically Induced Reprogramming to Pluripotency

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    Restoring pluripotency using chemical compounds alone would be a major step forward in developing clinical-grade pluripotent stem cells, but this has not yet been reported in human cells. We previously demonstrated that VPA_ AFS cells, human amniocytes cultivated with valproic acid (VPA) acquired functional pluripotency while remaining distinct from human embryonic stem cells (hESCs), questioning the relationship between the modulation of cell fate and molecular regulation of the pluripotency network. Here, we used single-cell analysis and functional assays to reveal that VPA treatment resulted in a homogeneous population of self-renewing non-transformed cells that fulfill the hallmarks of pluripotency, i.e., a short G1 phase, a dependence on glycolytic metabolism, expression of epigenetic modifications on histones 3 and 4, and reactivation of endogenous OCT4 and downstream targets at a lower level than that observed in hESCs. Mechanistic insights into the process of VPA-induced reprogramming revealed that it was dependent on OCT4 promoter activation, which was achieved independently of the PI3K (phosphatidylinositol 3-kinase)/ AKT/ mTOR (mammalian target of rapamycin) pathway or GSK3 beta inhibition but was concomitant with the presence of acetylated histones H3K9 and H3K56, which promote pluripotency. Our data identify, for the first time, the pluripotent transcriptional and molecular signature and metabolic status of human chemically induced pluripotent stem cells

    Welfare of rainbow trout at slaughter: integrating behavioural, physiological, proteomic and quality indicators and testing a novel fast-chill stunning method

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    A critical point in the life of a captive fish is the final stages of production, not only in welfare terms but also due to effects on meat quality, carcass appearance and derived economic impacts. The most common method to slaughter fish is by asphyxia either in ice-water or in the open air. In humane slaughter procedures, however, a stunning method needs to be implemented to render the fish immediately unconscious (within one second) until death. The objective of this research was to evaluate and compare the effectiveness and welfare effects of four types of stunning methods in rainbow trout (O. mykiss): cold shock by fast-chilling as a novel method, where the fish were immersed in liquid water at −8 °C, asphyxia (as the currently used method), electrical stunning, and anaesthesia with MS-222. We used a total of 176 trout (mean weight 524 ± 138 g), combining behavioural (individual swimming activity, equilibrium, opercular movement and eye-roll), physiological (heart rate and electrocardiogram amplitude) and circulating (plasma cortisol and osmolality) indicators with brain proteomic signatures. We also analysed the effects on fillet shelf-life and quality in each method (rigor mortis, water content, fillet colour, pH and ATP degradation). Anaesthesia effectively induced unconsciousness, with regular and strong heartbeat and low cortisol. Quality indicators were the best among all the methods assessed. Electric shock was found to be an effective and irreversible method for inducing unconsciousness, with strong heartbeat and large variation in cortisol response and quality indicators similar to anaesthesia. On the contrary, asphyxia presented indicators of poor welfare (e.g., long-lasting consciousness throughout the slaughter process, high cortisol levels), with very low flesh quality parameters. Fast-chilling also resulted in extreme signs of stress (intense mucus release, haemorrhage and no loss of consciousness), low ATP content and the worst proteomic signatures, along with an early onset and resolution of rigor mortis (6 and 48 h, respectively). Our results reinforce the idea that electric stunning is a promising humane method to stun farmed trout. In contrast, the fast-chilling method showed very poor results both in welfare and in quality, indicating that it is not a viable humane alternative to asphyxia. Moreover, the proteome analysis provided valuable insights into the brain mechanisms of rainbow trout at slaughter, offering potential fine-scale biomarkers of welfare.Provincia Autonoma di Trento; Fundação para a CiĂȘncia e a Tecnologiainfo:eu-repo/semantics/acceptedVersio

    Transglutaminase Type 2 Regulates ER-Mitochondria Contact Sites by Interacting with GRP75

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    Transglutaminase type 2 (TG2) is a multifunctional enzyme that plays a key role in mitochondria homeostasis under stressful cellular conditions. TG2 interactome analysis reveals an enzyme interaction with GRP75 (glucose-regulated protein 75). GRP75 localizes in mitochondria-associated membranes (MAMs) and acts as a bridging molecule between the two organelles by assembling the IP3R-GRP75-VDAC complex, which is involved in the transport of Ca2+ from the endoplasmic reticulum (ER) to mitochondria. We demonstrate that the TG2 and GRP75 interaction occurs in MAMs. The absence of the TG2-GRP75 interaction leads to an increase of the interaction between IP3R-3 and GRP75; a decrease of the number of ER-mitochondria contact sites; an impairment of the ER-mitochondrial Ca2+ flux; and an altered profile of the MAM proteome. These findings indicate TG2 is a key regulatory element of the MAMs

    A rational roadmap for SARS-CoV-2/COVID-19 pharmacotherapeutic research and development: IUPHAR Review 29.

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    In this review, we identify opportunities for drug discovery in the treatment of COVID-19 and, in so doing, provide a rational roadmap whereby pharmacology and pharmacologists can mitigate against the global pandemic. We assess the scope for targeting key host and viral targets in the mid-term, by first screening these targets against drugs already licensed, an agenda for drug repurposing, which should allow rapid translation to clinical trials. A simultaneous, multi-pronged approach using conventional drug discovery methods aimed at discovering novel chemical and biological means of targeting a short list of host and viral entities which should extend the arsenal of anti-SARS-CoV-2 agents. This longer term strategy would provide a deeper pool of drug choices for future-proofing against acquired drug resistance. Second, there will be further viral threats, which will inevitably evade existing vaccines. This will require a coherent therapeutic strategy which pharmacology and pharmacologists are best placed to provide. LINKED ARTICLES: This article is part of a themed issue on The Pharmacology of COVID-19. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.21/issuetoc.Welcome Trust 107715/Z/15/

    The IUPHAR Guide to Immunopharmacology: connecting immunology and pharmacology

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    Given the critical role that the immune system plays in a multitude of diseases, having a clear understanding of the pharmacology of the immune system is crucial to new drug discovery and development. Here we describe the International Union of Basic and Clinical Pharmacology (IUPHAR) Guide to Immunopharmacology (GtoImmuPdb), which connects expert-curated pharmacology with key immunological concepts and aims to put pharmacological data into the hands of immunologists. In the pursuit of new therapeutics, pharmacological databases are a vital resource to researchers through providing accurate information on the fundamental science underlying drug action. This extension to the existing IUPHAR/British Pharmacological Society Guide to Pharmacology supports research into the development of drugs targeted at modulating immune, inflammatory or infectious components of disease. To provide a deeper context for how the resource can support research we show data in GtoImmuPdb relating to a case study on the targeting of vascular inflammation

    The Concise Guide to PHARMACOLOGY 2023/24:Nuclear hormone receptors

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    The Concise Guide to PHARMACOLOGY 2023/24 is the sixth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of approximately 1800 drug targets, and nearly 6000 interactions with about 3900 ligands. There is an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (https://www.guidetopharmacology.org/), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes almost 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/10.1111/bph.16179. Nuclear hormone receptors are one of the six major pharmacological targets into which the Guide is divided, with the others being: G protein-coupled receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2023, and supersedes data presented in the 2021/22, 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate.</p
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