18 research outputs found

    Changing expression of vertebrate immunity genes in an anthropogenic environment: a controlled experiment

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    Background: The effect of anthropogenic environments on the function of the vertebrate immune system is a problem of general importance. For example, it relates to the increasing rates of immunologically-based disease in modern human populations and to the desirability of identifying optimal immune function in domesticated animals. Despite this importance, our present understanding is compromised by a deficit of experimental studies that make adequately matched comparisons between wild and captive vertebrates. Results: We transferred post-larval fishes (three-spined sticklebacks), collected in the wild, to an anthropogenic (captive) environment. We then monitored, over 11 months, how the systemic expression of immunity genes changed in comparison to cohort-matched wild individuals in the originator population (total n = 299). We found that a range of innate (lyz, defbl2, il1r-like, tbk1)and adaptive (cd8a, igmh) immunity genes were up-regulated in captivity, accompanied by an increase in expression of the antioxidant enzyme, gpx4a. For some genes previously known to show seasonality in the wild, this appeared to be reduced in captive fishes. Captive fishes tended to express immunity genes, including igzh, foxp3b, lyz, defbl2, and il1r-like, more variably. Furthermore, although gene co-expression patterns (analyzed through gene-by-gene correlations and mutual information theory based networks) shared common structure in wild and captive fishes, there was also significant divergence. For one gene in particular, defbl2, high expression was associated with adverse health outcomes in captive fishes. Conclusion: Taken together, these results demonstrate widespread regulatory changes in the immune system in captive populations, and that the expression of immunity genes is more constrained in the wild. An increase in constitutive systemic immune activity, such as we observed here, may alter the risk of immunopathology and contribute to variance in health in vertebrate populations exposed to anthropogenic environments

    Proposed method for agglutinating antibody titer analysis and its use as indicator of acquired immunity in pacu, Piaractus mesopotamicus

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    Antibody can be assessed by agglutinating antibody titer which is a quantitative measure of circulating antibodies in serum from fish previously immunized. The antibody evaluation has been performed with different fish species, and is considered a reliable method that can be applied to confirm several hypothesis regarding acquired immunity, even in conjunction with precise methods to describe immune mechanisms. In order to provide appropriate analytical methods for future studies on the specific immune system of native fish, the present study standardized on assay to measure the serum agglutinating antibody titer produced after immunization with inactivated A. hydrophila and levamisole administration in pacu. It was possible to determine the agglutinating antibodies titer in a satisfactorily way in pacu immunized with inactive A. hydrophila, and the highest titers were observed on fish fed with levamisole

    Proposed method for agglutinating antibody titer analysis and its use as indicator of acquired immunity in pacu, Piaractus mesopotamicus

    No full text
    Antibody can be assessed by agglutinating antibody titer which is a quantitative measure of circulating antibodies in serum from fish previously immunized. The antibody evaluation has been performed with different fish species, and is considered a reliable method that can be applied to confirm several hypothesis regarding acquired immunity, even in conjunction with precise methods to describe immune mechanisms. In order to provide appropriate analytical methods for future studies on the specific immune system of native fish, the present study standardized on assay to measure the serum agglutinating antibody titer produced after immunization with inactivated A. hydrophila and levamisole administration in pacu. It was possible to determine the agglutinating antibodies titer in a satisfactorily way in pacu immunized with inactive A. hydrophila, and the highest titers were observed on fish fed with levamisole

    Leukocytes respiratory burst activity as indicator of innate immunity of pacu Piaractus mesopotamicus

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    The present study evaluated the assay to quantify the respiratory burst activity of blood leukocytes of pacu as an indicator of the innate immune system, using the reduction of nitroblue tetrazolium (NBT) to formazan as a measure of the production of reactive oxygen species (ROS). In order to assess the accuracy of the assay, fish were challenged by Aeromonas hydrophila and sampled one week after challenge. The A. hydrophila infection increased the leukocyte respiratory burst activity. The protocol showed a reliable and easy assay, appropriate to determine the respiratory burst activity of blood leukocytes of pacu, a neotropical fish, in the present experimental conditions

    Leukocytes respiratory burst activity as indicator of innate immunity of pacu Piaractus mesopotamicus

    No full text
    The present study evaluated the assay to quantify the respiratory burst activity of blood leukocytes of pacu as an indicator of the innate immune system, using the reduction of nitroblue tetrazolium (NBT) to formazan as a measure of the production of reactive oxygen species (ROS). In order to assess the accuracy of the assay, fish were challenged by Aeromonas hydrophila and sampled one week after challenge. The A. hydrophila infection increased the leukocyte respiratory burst activity. The protocol showed a reliable and easy assay, appropriate to determine the respiratory burst activity of blood leukocytes of pacu, a neotropical fish, in the present experimental conditions

    Disease resistance of pacu Piaractus mesopotamicus (Holmberg, 1887) fed with β-glucan

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    Effects of β-glucan on innate immune responses and survival were studied in pacu experimentally infected with Aeromonas hydrophila. Fish fed diets containing 0, 0.1% and 1% β-glucan were injected with A. hydrophila. β-glucan enhanced fish survival in both treated groups (26.7% and 21.2% of the control, respectively). Leukocyte respiratory burst and alternative complement pathway activities were elevated after bacterial challenge regardless the β-glucan concentration. Lysozyme activity was higher after infection and showed a gradual increase as β-glucan concentration increased. A significant elevation in WBC count was observed either after bacterial challenge or by influence of β-glucan separately. The same response was observed in the number of thrombocytes, lymphocytes, eosinophils, LG-PAS positive cell and monocytes. It can be concluded that feeding pacu with β-glucan can increase protection against A. hydrophila, due to changes in non-specific immune responses

    Consensus on diagnosis and management of Cushing's disease: a guideline update

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    Cushing's disease requires accurate diagnosis, careful treatment selection, and long-term management to optimise patient outcomes. The Pituitary Society convened a consensus workshop comprising more than 50 academic researchers and clinical experts to discuss the application of recent evidence to clinical practice. In advance of the virtual meeting, data from 2015 to present about screening and diagnosis; surgery, medical, and radiation therapy; and disease-related and treatment-related complications of Cushing's disease summarised in recorded lectures were reviewed by all participants. During the meeting, concise summaries of the recorded lectures were presented, followed by small group breakout discussions. Consensus opinions from each group were collated into a draft document, which was reviewed and approved by all participants. Recommendations regarding use of laboratory tests, imaging, and treatment options are presented, along with algorithms for diagnosis of Cushing's syndrome and management of Cushing's disease. Topics considered most important to address in future research are also identified
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