Publications by authors named "Maria Dahle"

Infectious Salmon Anaemia virus (ISAV) is an orthomyxovirus that causes large economic losses in Atlantic salmon (Salmo salar L.) aquaculture. All virulent ISAV variants originally emerged from a non-virulent subtype, ISAV-HPR0.

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Piscine orthoreovirus (PRV) infection is common in aquaculture of salmonids. The three known PRV genotypes (PRV-1-3) have host species specificity and cause different diseases, but all infect and replicate in red blood cells (RBCs) in early infection phase. PRV-1 is the causative agent of heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (Salmo salar), PRV-2 causes erythrocytic inclusion body syndrome (EIBS) in coho salmon (Oncorhynchus kisutch), while PRV-3 induces HSMI-like disease in farmed rainbow trout (Oncorhynchus mykiss).

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  • Triple negative breast cancer (TNBC) poses treatment challenges due to chemotherapy resistance and tumor diversity, prompting researchers to identify molecular pathways and patient sub-groups for targeted therapies.
  • Using RNA sequencing and reverse phase protein analysis on patient-derived xenografts, the study discovered that signaling pathways like SRC-family kinases (SFKs) and MAPK/ERK are more active in chemotherapy-resistant tumors, indicating potential targets for treatment.
  • High expression of these pathways correlates with poor outcomes in some TNBC patients, suggesting that those with elevated SFK levels, particularly in metastatic lesions, could benefit from future SFK-targeted therapies.
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  • Scientists studied how PRV-1, a virus, affects Atlantic salmon by looking for specific signs in their blood called metabolites.
  • They compared healthy salmon with sick ones at different stages of the disease to see how the virus changed things inside the fish.
  • They found that the virus really messed up the way fats are processed in the salmon’s body, which helped them learn more about how the disease develops.
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  • Farmed rainbow trout can have color changes in their meat, similar to farmed Atlantic salmon, but we didn’t know much about them before this study.
  • Researchers looked at 1293 rainbow trout in Norway when they were being slaughtered and found that these changes (called MFCs) happen in about 1.46% to 6.47% of the fish.
  • They discovered some viruses related to these changes, but the type of damage looked different in rainbow trout compared to Atlantic salmon, which might explain why rainbow trout don't have these issues as often.
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Piscine red blood cells (RBC) are nucleated and have been characterized as mediators of immune responses in addition to their role in gas exchange. Salmonid RBC are major target cells of Piscine orthoreovirus1 (PRV-1), the etiological agent of heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (). PRV-1 replicates in RBC , but no viral amplification has been possible in available A.

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Fish gills are not only the respiratory organ, but also essential for ion-regulation, acid-base control, detoxification, waste excretion and host defense. Multifactorial gill diseases are common in farmed Atlantic salmon, and still poorly understood. Understanding gill pathophysiology is of paramount importance, but the sacrifice of large numbers of experimental animals for this purpose should be avoided.

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Purpose: Hypoxic tumors are associated with therapy resistance and poor cancer prognosis, but methods to detect and counter tumor hypoxia remain insufficient. Our purpose was to investigate Cu(II)-elesclomol ([Cu][Cu(ES)]) as a novel theranostic agent for hypoxic tumors, by implementing an improved production method and assessing its therapeutic and diagnostic potential compared to the established Cu-64 radiopharmaceuticals [Cu]CuCl and [diacetyl-bis(N4-methylthiosemicarbazone) [Cu][Cu(ATSM)].

Methods: Cu-64 was produced using a biomedical cyclotron at 12 MeV with the reaction Ni(p,n)Cu, followed by synthesis of [Cu]CuCl, [Cu][Cu(ATSM)], and [Cu][Cu(ES)].

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The Salmon gill poxvirus (SGPV) has emerged in recent years as the cause of an acute respiratory disease that can lead to high mortality in farmed Atlantic salmon presmolts, known as Salmon gill poxvirus disease. SGPV was first identified in Norway in the 1990s, and its large DNA genome, consisting of over 206 predicted protein-coding genes, was characterized in 2015. This review summarizes current knowledge relating to disease manifestation and its effects on the host immune system and describes dissemination of the virus.

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Protective cellular immune responses have been difficult to study in fish, due to lack of basic understanding of their T cell populations, and tools to study them. Cellular immunity is thus mostly ignored in vaccination and infection studies compared to humoral responses. High throughput sequencing, as well as access to well assembled genomes, now advances studies of cellular responses.

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  • Mucous membranes like the gill and skin mucosa in fish serve as protective barriers and reflect environmental interactions as well as fish health.
  • The study utilized liquid chromatography and high-resolution mass spectrometry (LC-HRMS) to analyze the metabolite profiles of plasma, skin, and gill mucus in freshwater Atlantic salmon.
  • Results indicated a strong correlation in metabolite composition across different biological fluids, suggesting that mucus analysis could be an effective tool for monitoring fish health.
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Piscine orthoreovirus (PRV-1) infection causes heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon . The virus is also associated with focal melanized changes in white skeletal muscle where PRV-1 infection of macrophages appears to be important. In this study, we studied the macrophage polarization into M1 (pro-inflammatory) and M2 (anti-inflammatory) phenotypes during experimentally induced HSMI.

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  • Lumpfish are increasingly used in salmon farming to combat sea lice, but there’s limited understanding of their biology.
  • Researchers established the first Lumpfish Gill cell line (LG-1), which shares characteristics with epithelial or endothelial cells, including specific cellular structures and resistance properties.
  • The LG-1 cell line also supports the growth of various harmful viruses, making it a significant resource for studying gill cell functions and disease interactions in lumpfish.
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Salmon Gill Poxvirus Disease (SGPVD) has emerged as a cause of acute mortality in Atlantic salmon () presmolts in Norwegian aquaculture. The clinical phase of the disease is associated with apoptotic cell death in the gill epithelium causing acute respiratory distress, followed by proliferative changes in the regenerating gill in the period after the disease outbreak. In an experimental SGPV challenge trial published in 2020, acute disease was only seen in fish injected with hydrocortisone 24 h prior to infection.

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Melanized focal changes in white skeletal muscle of farmed Atlantic salmon, "black spots", is a quality problem affecting on average 20% of slaughtered fish. The spots appear initially as "red spots" characterized by hemorrhages and acute inflammation and progress into black spots characterized by chronic inflammation and abundant pigmented cells. 1 (PRV-1) was previously found to be associated with macrophages and melano-macrophages in red and black spots.

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Heart and skeletal muscle inflammation (HSMI), caused by infection with (PRV-1), is a common disease in farmed Atlantic salmon (). Both an inactivated whole virus vaccine and a DNA vaccine have previously been tested experimentally against HSMI and demonstrated to give partial but not full protection. To understand the mechanisms involved in protection against HSMI and evaluate the potential of live attenuated vaccine strategies, we set up a cross-protection experiment using PRV genotypes not associated with disease development in Atlantic salmon.

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Piscine orthoreovirus 1 (PRV-1) is the causative agent of heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (). The virus is widespread in Atlantic salmon and was present in Norway long before the first description of HSMI in 1999. Furthermore, in Canada the virus is prevalent in farmed Atlantic salmon but HSMI is not and Canadian isolates have failed to reproduce HSMI experimentally.

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The salmon gill poxvirus (SGPV) is a large DNA virus that infects gill epithelial cells in Atlantic salmon and is associated with acute high mortality disease outbreaks in aquaculture. The pathological effects of SGPV infection include gill epithelial apoptosis in the acute phase of the disease and hyperplasia of gill epithelial cells in surviving fish, causing damage to the gill respiratory surface. In this study, we sampled gills from Atlantic salmon presmolts during a natural outbreak of SGPV disease (SGPVD).

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Salmonid alphavirus (SAV) is the etiological cause of pancreas disease (PD) in Atlantic salmon (Salmo salar). Several vaccines against SAV are in use, but PD still cause significant mortality and concern in European aquaculture, raising the need for optimal tools to monitor SAV immunity. To monitor and control the distribution of PD in Norway, all salmonid farms are regularly screened for SAV by RT-qPCR.

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Piscine orthoreovirus infects various salmonid fish species, and the infection is associated with diseases such as heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (Salmo salar). There are no vaccines available or genetically selected resistant hosts that can efficiently control piscine orthoreovirus (PRV) infection. Currently, the only prophylactic measure against PRV is general biosecurity measures aiming to break the transmission cycle.

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Salmon gill poxvirus (SGPV) can cause serious gill disease in Atlantic salmon ( L.) and represents a significant problem to aquaculture industries in Northern Europe. Here, a single-tube multi-locus variable-number tandem-repeat (VNTR) analysis (MLVA) genotyping assay, targeting eight VNTR loci, was developed for studying the epizootiology of SGPV.

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Article Synopsis
  • Salmon gill poxvirus (SGPV) is linked to complex gill disease in Norwegian salmon farming and can lead to salmon poxvirus disease (SGPVD), with stress being a significant factor influencing disease onset.
  • An experiment involved injecting Atlantic salmon with hydrocortisone to assess its impact on SGPV levels and disease development compared to a control group receiving a sham injection.
  • Results showed that hydrocortisone-treated fish had higher cortisol and SGPV levels, developed SGPVD symptoms and increased mortality, indicating that elevated cortisol is crucial for SGPVD progression and highlighting the need to reduce stress in salmon farming practices.
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(PRV-1) can cause heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (), but the line of events from infection, pathologic change, and regeneration has not been thoroughly described. In this study, the cellular localization and variation of PRV-1 RNA and protein levels were analyzed at different times post-exposure in experimentally infected Atlantic salmon. Immunohistochemistry, flow cytometry, and Western blot were used for assessment of the presence of the PRV-1 σ1 protein, while RT-qPCR and in situ hybridization were performed for viral RNA.

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Bead-based multiplex immunoassays are promising tools for determination of the specific humoral immune response. In this study, we developed a multiplexed bead-based immunoassay for the detection of Atlantic salmon () antibodies against (PRV). Three different genotypes of PRV (PRV-1, PRV-2, and PRV-3) cause disease in farmed salmonids.

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Piscine orthoreovirus (PRV-1) can cause heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (). The virus targets erythrocytes in the acute peak phase, followed by cardiomyocytes, before the infection subsides into persistence. The persistent phase is characterized by high level of viral RNA, but low level of viral protein.

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