Setting up a global SARS-CoV-2 surveillance system requires an understanding of how virus isolation and propagation practices, use of animal or human sera, and different neutralisation assay platforms influence assessment of SARS-CoV-2 antigenicity. In this study, with the contribution of 15 independent laboratories across all WHO regions, we carried out a controlled analysis of neutralisation assay platforms using the first WHO International Standard for antibodies to SARS-CoV-2 variants of concern (source: NIBSC). Live virus isolates (source: WHO BioHub or individual labs) or spike plasmids (individual labs) for pseudovirus production were used to perform neutralisation assays using the same serum panels.
View Article and Find Full Text PDFThis study investigated the impact of an oxygen-rich spray on rainbow trout subjected to short-term air exposure episodes. These episodes can be due to sampling procedures or catch-and-release (C&R) practices, focusing on behavioral, haematological, and physiological responses. For this, 12 rainbow trout were divided into two groups: control and oxygen-rich sprayed fish.
View Article and Find Full Text PDFThe effectiveness of vaccines may be compromised by the stress response induced by intraperitoneal/intramuscular (IP/IM) vaccination due to an intimate interaction between the neuroendocrine and immune systems. Essential oils (EOs), known for their antibacterial, antioxidant, and sedative properties, are potential candidates to mitigate this stress response. This study investigates the short-term sedative effect of two essential oil-based products, FishEase-C (FEC) and FishEase-L (FEL) in sea bass prior to intraperitoneal vaccination (IP).
View Article and Find Full Text PDFMem Inst Oswaldo Cruz
September 2024
Mucosal tissues appear to be more important in fish than in mammals due to living in a microbial-rich aquatic milieu, yet the complex interaction between the immune and the neuroendocrine system in these tissues remains elusive. The aim of this work was to investigate the mucosal immune response in immunized rainbow trout vaccinated with Alpha ject vaccine (bivalent), kept in fresh water (FW) or transferred to seawater (SW), and to evaluate their response to acute stress (chasing). Acute stress resulted in higher levels of plasma cortisol (Sham + Stress and Vaccine + Stress).
View Article and Find Full Text PDFThe skin of bony fish is the first physical barrier and is responsible for maintaining the integrity of the fish. Lesions make the skin vulnerable to potential infection by pathogens present in the aquatic environment. In this way, wound repair has barely been studied in gilthead sea bream.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
September 2024
In recent years, there has been a burgeoning interest in exploring the nuances of animal stress physiology, particularly in relation to parameters such as sex and behavioral phenotype-dependent variations, which is crucial for understanding phenotypic variation and its role in evolutionary selection. However, a significant dearth remains in how chronic stressors affect organismal stress physiology concerning the aforesaid parameters. This void is even wider pertaining to the response of peripheral tissues, such as the skin, the organ with the highest surface contact area with the environment.
View Article and Find Full Text PDFUnder climate change, the increase in temperature in aquatic environments may induce oxygen depletion. In extreme cases, low oxygen may become a limiting factor for fish, thus generating stress. In addition, consecutive hypoxic episodes may complicate the recovery of individuals and hinder their ability to modulate physiological and biochemical responses to maintain homeostasis.
View Article and Find Full Text PDFWhen necessary, sea turtles are held captive for veterinarian care and research purposes. Protocols and basic guidelines have been described for husbandry of sea turtles with veterinarian needs but not considering physiological indicators of animal welfare. Because all sea turtle are imperiled species, monitoring their welfare is important.
View Article and Find Full Text PDFThe widespread use of pesticides in some areas where fish species such as tilapia are farmed may cause damage to the environment and affect commercial fish and therefore, human health. Water leaching with the pesticide trichlorfon, during the fumigation season in the field, can affect water quality in fish farms and consequently affect fish health. At the same time, the use of immunomodulatory compounds such as β-glucan supplied in the diet has become widespread in fish farms as it has been shown that improves the overall immune response.
View Article and Find Full Text PDFBraz J Infect Dis
March 2024
This study compares the effects of virus-cell interactions among SARS-CoV-2 variants of concern (VOCs) isolated in Brazil in 2021, hypothesizing a correlation between cellular alterations and mortality and between viral load and transmissibility. For this purpose, reference isolates of Alpha, Gamma, Zeta, and Delta variants were inoculated into monolayers of Vero-E6 cells. Viral RNA was quantified in cell supernatants by RT‒PCR, and infected cells were analyzed by Transmission Electron Microscopy (TEM) for qualitative and quantitative evaluation of cellular changes 24, 48, and 72 hours postinfection (hpi).
View Article and Find Full Text PDFThe present study explores the effects of two supplementation levels of (1.1% and 2.2%) as a probiotic in a reference low fish meal-based diet on the skin mucosal tissue in .
View Article and Find Full Text PDFNew variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have emerged, imposing the need for periodic booster doses. However, whether booster doses should be applied to the entire population or groups, and the booster doses interval, remains unclear. In this study, we evaluated humoral reactivity kinetics from before the first dose to 180 days after the third booster dose in different schedules in a well-controlled health worker cohort.
View Article and Find Full Text PDFBackground: The development of a sustainable business model with social acceptance, makes necessary to develop new strategies to guarantee the growth, health, and well-being of farmed animals. Debaryomyces hansenii is a yeast species that can be used as a probiotic in aquaculture due to its capacity to i) promote cell proliferation and differentiation, ii) have immunostimulatory effects, iii) modulate gut microbiota, and/or iv) enhance the digestive function. To provide inside into the effects of D.
View Article and Find Full Text PDFThe main objective of this study was to investigate the dynamic of SARS-CoV-2 viral excretion in rectal swab (RS), saliva, and nasopharyngeal swab (NS) samples from symptomatic patients and asymptomatic contacts. In addition, in order to evaluate the replication potential of SARS-CoV-2 in the gastrointestinal (GI) tract and the excretion of infectious SARS-CoV-2 from feces, we investigated the presence of subgenomic nucleoprotein gene (N) mRNA (sgN) in RS samples and cytopathic effects in Vero cell culture. A prospective cohort study was performed to collect samples from symptomatic patients and contacts in Rio de Janeiro, Brazil, from May to October 2020.
View Article and Find Full Text PDFCOVID-19 vaccines have dramatically reduced rates of severe infection requiring hospitalization. However, SARS-CoV-2 variants have reduced vaccine effectiveness at preventing any symptomatic infection. This real-world study analyzed binding and neutralizing antibodies generated after complete vaccination and boosting across three vaccine platforms.
View Article and Find Full Text PDFThe rapid spread of the SARS-CoV-2 Variant of Concern (VOC) Gamma in Amazonas during early 2021 fueled a second large COVID-19 epidemic wave and raised concern about the potential role of reinfections. Very few cases of reinfection associated with the VOC Gamma have been reported to date, and their potential impact on clinical, immunological, and virological parameters remains largely unexplored. Here we describe 25 cases of SARS-CoV-2 reinfection in Brazil.
View Article and Find Full Text PDFIn this study, we investigated the effects of the artificial photoperiods that mimic summer (16L:8D; 16 h Light: 8 h Dark) and winter (8L:16D) solstices, equinoxes (12L:12D), and the artificial 24-h light regimen (24L:0D) on the leukocyte populations and the T helper and regulatory type responses on rainbow trout (Oncorhynchus mykiss). Using flow cytometry analysis, we found that photoperiod induces changes in head kidney leukocyte subsets. The lymphoid subset increased in the 16L:8D summer solstice regime.
View Article and Find Full Text PDFThe most documented fibrates are gemfibrozil, clofibrate and bezafibrate, while for statins, the majority of the published literature focuses on atorvastatin and simvastatin. The present work reviews previously published research concerning the effects of these hypocholesterolaemic pharmaceuticals on fish, with a particular focus on commercially important species, commonly produced by the European aquaculture industry, specifically in recirculated aquaculture systems (RAS). Overall, results suggest that both acute and chronic exposures to lipid-lowering compounds may have adverse effects on fish, disrupting their capacity to excrete exogenous substances, as well as both lipid metabolism and homeostasis, causing severe ontogenetic and endocrinological abnormalities, leading to hampered reproductive success (e.
View Article and Find Full Text PDFOvercoming a stress situation, such as hypoxia episodes, which involve an allostatic load, will depend on the ability of fish to modulate physiological and biochemical systems to maintain homeostasis. The aim of the study was to determine the integrated stress response after acute hypoxia of the rainbow trout considering the different elements and areas of the stress response: systemic and mucosal, local and global, and from the systemic hypothalamic-pituitary-interrenal axis to skin mucosa. For this purpose, trout were subjected to acute hypoxia (dissolved O down to 2 mg/L) for 1 h and then recovered and sampled at 1, 6, and 24 h after reoxygenation.
View Article and Find Full Text PDFThe melanocortin system is an ancient neuroendocrine system conserved from teleosts to mammals. The melanocortin system is a set of complex neuroendocrine signaling pathways involved in numerous physiological processes, and particularly associated with the hypothalamic-pituitary-interrenal (HPI) axis response. The melanocortin 1 receptor (MC1R) is the central melanocortin receptor involved in pigmentation in vertebrates, including fish.
View Article and Find Full Text PDFIntroduction: Transcranial magnetic stimulation (TMS) is a consolidated procedure for the treatment of depression, with several meta-analyses demonstrating its efficacy. Theta-burst stimulation (TBS) is a modification of TMS with similar efficacy and shorter session duration. The geriatric population has many comorbidities and a high prevalence of depression, but few clinical trials are conducted specifically for this age group.
View Article and Find Full Text PDFis a marine zoonotic pathogen associated with fish farms that is considered a biomarker of climate change. Zoonotic strains trigger a rapid death of their susceptible hosts (fish or humans) by septicemia that has been linked to a cytokine storm in mice. Therefore, we hypothesize that also causes fish death by triggering a cytokine storm in which red blood cells (RBCs), as nucleated cells in fish, could play an active role.
View Article and Find Full Text PDFIn the present study, the modulation of the transcriptional immune response (microarray analysis) in the head kidney (HK) of the anadromous fish Atlantic salmon () fed a diet supplemented with an olive fruit extract (AQUOLIVE) was evaluated. At the end of the trial (133 days), in order to investigate the immunomodulatory properties of the phytogenic tested against a bacterial infection, an challenge with was performed. A total number of 1,027 differentially expressed genes (DEGs) (805 up- and 222 downregulated) were found when comparing the transcriptomic profiling of the HK from fish fed the control and AQUOLIVE diets.
View Article and Find Full Text PDF