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Petersen PE, Dahl MM, Vest NMO, Jansen MD, Fosse JH, Falk K, Christiansen DH. Validation of a TaqMan one-step real-time RT-PCR assay targeting ISAV segment 7 spliced mRNA. J Virol Methods 2023; 321:114791. [PMID: 37562733 DOI: 10.1016/j.jviromet.2023.114791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 07/31/2023] [Accepted: 08/07/2023] [Indexed: 08/12/2023]
Abstract
Infectious salmon anaemia virus (ISAV) can cause severe systemic infection in Atlantic salmon (Salmo salar L.), and a timely diagnosis is critical. Conventional real-time reverse transcription PCR (RT-qPCR) assays target unspliced RNA from either ISAV segment 7 or 8 and provide data on viral load. Here, we evaluate a TaqMan one-step RT-qPCR assay that detects explicitly a spliced messenger RNA (mRNA) of ISAV segment 7, thus providing evidence of active viral transcription. Assay performance was comparable with existing unspliced segment 7 and segment 8 assays. PCR efficiency as evaluated from dilutions of a synthetic DNA fragment was 98 % (R2 = 1.00). The assay also performed well on clinical heart samples with PCR efficiency of 108 % (R2 = 1.00). Finally, evaluation on kidney samples from experimental infection revealed higher levels of active transcription for high-virulent compared to low-virulent ISAV. At early, peak, and late infection, mean ratios of spliced to unspliced segment 7 RNA were 3.0 % (± 0.7), 1.7 % (± 0.3), and 1.5 % (± 0.1) for the low virulent and 9.4 % (± 2.2), 4.7 % (± 0.8), and 6.2 % (± 0.1) for the high virulent isolate, respectively. By detection and quantification of active ISAV transcription, this assay may provide a more detailed understanding of ISAV infection dynamics.
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Affiliation(s)
- Petra Elisabeth Petersen
- Faroese Food and Veterinary Authority, National Reference Laboratory for Fish Diseases, V.U. Hammershaimbsg. 11, FO-100 Tórshavn, the Faroe Islands.
| | - Maria Marjunardóttir Dahl
- Faroese Food and Veterinary Authority, National Reference Laboratory for Fish Diseases, V.U. Hammershaimbsg. 11, FO-100 Tórshavn, the Faroe Islands
| | - Nicolina Maria Ovadóttir Vest
- Faroese Food and Veterinary Authority, National Reference Laboratory for Fish Diseases, V.U. Hammershaimbsg. 11, FO-100 Tórshavn, the Faroe Islands
| | - Mona Dverdal Jansen
- Norwegian Veterinary Institute, Elizabeth Stephansens vei 1, Pb 64, N-1431 Ås, Norway
| | - Johanna Hol Fosse
- Norwegian Veterinary Institute, Elizabeth Stephansens vei 1, Pb 64, N-1431 Ås, Norway
| | - Knut Falk
- Norwegian Veterinary Institute, Elizabeth Stephansens vei 1, Pb 64, N-1431 Ås, Norway
| | - Debes Hammershaimb Christiansen
- Faroese Food and Veterinary Authority, National Reference Laboratory for Fish Diseases, V.U. Hammershaimbsg. 11, FO-100 Tórshavn, the Faroe Islands
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2
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Fosse JH, Andresen AMS, Ploss FB, Weli SC, Heffernan IA, Sapkota S, Lundgård K, Kuiper RV, Solhaug A, Falk K. The infectious salmon anemia virus esterase prunes erythrocyte surfaces in infected Atlantic salmon and exposes terminal sialic acids to lectin recognition. Front Immunol 2023; 14:1158077. [PMID: 37180109 PMCID: PMC10167051 DOI: 10.3389/fimmu.2023.1158077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 04/03/2023] [Indexed: 05/15/2023] Open
Abstract
Many sialic acid-binding viruses express a receptor-destroying enzyme (RDE) that removes the virus-targeted receptor and limits viral interactions with the host cell surface. Despite a growing appreciation of how the viral RDE promotes viral fitness, little is known about its direct effects on the host. Infectious salmon anemia virus (ISAV) attaches to 4-O-acetylated sialic acids on Atlantic salmon epithelial, endothelial, and red blood cell surfaces. ISAV receptor binding and destruction are effectuated by the same molecule, the haemagglutinin esterase (HE). We recently discovered a global loss of vascular 4-O-acetylated sialic acids in ISAV-infected fish. The loss correlated with the expression of viral proteins, giving rise to the hypothesis that it was mediated by the HE. Here, we report that the ISAV receptor is also progressively lost from circulating erythrocytes in infected fish. Furthermore, salmon erythrocytes exposed to ISAV ex vivo lost their capacity to bind new ISAV particles. The loss of ISAV binding was not associated with receptor saturation. Moreover, upon loss of the ISAV receptor, erythrocyte surfaces became more available to the lectin wheat germ agglutinin, suggesting a potential to alter interactions with endogenous lectins of similar specificity. The pruning of erythrocyte surfaces was inhibited by an antibody that prevented ISAV attachment. Furthermore, recombinant HE, but not an esterase-silenced mutant, was sufficient to induce the observed surface modulation. This links the ISAV-induced erythrocyte modulation to the hydrolytic activity of the HE and shows that the observed effects are not mediated by endogenous esterases. Our findings are the first to directly link a viral RDE to extensive cell surface modulation in infected individuals. This raises the questions of whether other sialic acid-binding viruses that express RDEs affect host cells to a similar extent, and if such RDE-mediated cell surface modulation influences host biological functions with relevance to viral disease.
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3
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Wagner M, Kutlu A, Minesinger G, Falk K, Speidel M, Laeseke P. Abstract No. 243 Multidetector CT-Guided Histotripsy: A Targeting Solution for Closed-Bore Imaging Systems. J Vasc Interv Radiol 2023. [DOI: 10.1016/j.jvir.2022.12.306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023] Open
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4
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Falk K, Kisting M, White J, Lee F, Ziemlewicz T, Speidel M, Wagner M, Laeseke P. Abstract No. 161 Targeting for Transcostal Histotripsy: Effect of Intervening Ribs on Treatment Zone Size. J Vasc Interv Radiol 2023. [DOI: 10.1016/j.jvir.2022.12.215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023] Open
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5
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Pan X, Šmíd M, Štefaníková R, Donat F, Baehtz C, Burian T, Cerantola V, Gaus L, Humphries OS, Hajkova V, Juha L, Krupka M, Kozlová M, Konopkova Z, Preston TR, Wollenweber L, Zastrau U, Falk K. Imaging x-ray spectrometer at the high energy density instrument of the European x-ray free electron laser. Rev Sci Instrum 2023; 94:033501. [PMID: 37012789 DOI: 10.1063/5.0133639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 02/03/2023] [Indexed: 06/19/2023]
Abstract
A multipurpose imaging x-ray crystal spectrometer is developed for the high energy density instrument of the European X-ray Free Electron Laser. The spectrometer is designed to measure x rays in the energy range of 4-10 keV, providing high-resolution, spatially resolved spectral measurements. A toroidally bent germanium (Ge) crystal is used, allowing x-ray diffraction from the crystal to image along a one-dimensional spatial profile while spectrally resolving along the other. A detailed geometrical analysis is performed to determine the curvature of the crystal. The theoretical performance of the spectrometer in various configurations is calculated by ray-tracing simulations. The key properties of the spectrometer, including the spectral and spatial resolution, are demonstrated experimentally on different platforms. Experimental results prove that this Ge spectrometer is a powerful tool for spatially resolved measurements of x-ray emission, scattering, or absorption spectra in high energy density physics.
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Affiliation(s)
- X Pan
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - M Šmíd
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - R Štefaníková
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - F Donat
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - C Baehtz
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - T Burian
- Institute of Physics of the ASCR, 18221 Prague, Czech Republic
| | - V Cerantola
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - L Gaus
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - O S Humphries
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - V Hajkova
- Institute of Physics of the ASCR, 18221 Prague, Czech Republic
| | - L Juha
- Institute of Physics of the ASCR, 18221 Prague, Czech Republic
| | - M Krupka
- Institute of Physics of the ASCR, 18221 Prague, Czech Republic
| | - M Kozlová
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - Z Konopkova
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - T R Preston
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - L Wollenweber
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - U Zastrau
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - K Falk
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
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6
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Aamelfot M, Fosse JH, Viljugrein H, Ploss FB, Benestad SL, McBeath A, Christiansen DH, Garver K, Falk K. Destruction of the vascular viral receptor in infectious salmon anaemia provides in vivo evidence of homologous attachment interference. PLoS Pathog 2022; 18:e1010905. [PMID: 36240255 PMCID: PMC9621750 DOI: 10.1371/journal.ppat.1010905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 10/31/2022] [Accepted: 10/01/2022] [Indexed: 11/06/2022] Open
Abstract
Viral interference is a process where infection with one virus prevents a subsequent infection with the same or a different virus. This is believed to limit superinfection, promote viral genome stability, and protect the host from overwhelming infection. Mechanisms of viral interference have been extensively studied in plants, but remain poorly understood in vertebrates. We demonstrate that infection with infectious salmon anaemia virus (ISAV) strongly reduces homologous viral attachment to the Atlantic salmon, Salmo salar L. vascular surface. A generalised loss of ISAV binding was observed after infection with both high-virulent and low-virulent ISAV isolates, but with different kinetics. The loss of ISAV binding was accompanied by an increased susceptibility to sialidase, suggesting a loss of the vascular 4-O-sialyl-acetylation that mediates ISAV attachment and simultaneously protects the sialic acid from cleavage. Moreover, the ISAV binding capacity of cultured cells dramatically declined 3 days after ISAV infection, accompanied by reduced cellular permissiveness to infection with a second antigenically distinct isolate. In contrast, neither infection with infectious haematopoietic necrosis virus nor stimulation with the viral mimetic poly I:C restricted subsequent cellular ISAV attachment, revealing an ISAV-specific mechanism rather than a general cellular antiviral response. Our study demonstrates homologous ISAV attachment interference by de-acetylation of sialic acids on the vascular surface. This is the first time the kinetics of viral receptor destruction have been mapped throughout the full course of an infection, and the first report of homologous attachment interference by the loss of a vascular viral receptor. Little is known about the biological functions of vascular O-sialyl-acetylation. Our findings raise the question of whether this vascular surface modulation could be linked to the breakdown of central vascular functions that characterises infectious salmon anaemia. Viral interference, also referred to as superinfection exclusion, is a process that supports viral genome integrity and protects the host from overwhelming infection. Here, we demonstrate that infection of Atlantic salmon with infectious salmon anaemia virus (ISAV) results in the destruction of the viral vascular surface receptor, thus preventing virus attachment. We also observed that the loss of viral receptor strongly restricted the extent of a second ISAV infection in cultured cells, suggesting viral interference. To our knowledge, this is the first time the kinetics of viral receptor destruction has been explored in an infected host. This is important, because we know little of how such responses develop in animals and humans. Our study therefore improves the general understanding of how viral infections progress. Finally, our findings raise the question of whether modulation of the vascular surface by ISAV and other viruses may contribute to the pathogenesis of viral disease.
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Affiliation(s)
| | | | | | | | | | | | | | - Kyle Garver
- Fisheries and Oceans Canada Pacific Biological Station, Nanaimo, British Columbia, Canada
| | - Knut Falk
- Norwegian Veterinary Institute, Ås, Norway
- * E-mail:
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7
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Fosse JH, Aamelfot M, Sønstevold T, Weli SC, Vendramin N, Petersen PE, Solhaug A, Amundsen MM, Heffernan IA, Cuenca A, Christiansen DH, Falk K. Salmon Erythrocytes Sequester Active Virus Particles in Infectious Salmon Anaemia. Viruses 2022; 14:v14020310. [PMID: 35215905 PMCID: PMC8879071 DOI: 10.3390/v14020310] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 01/27/2022] [Accepted: 01/28/2022] [Indexed: 02/06/2023] Open
Abstract
Infectious salmon anaemia virus (ISAV) binds circulating Atlantic salmon erythrocytes, but the relevance of this interaction for the course of infection and development of disease remains unclear. We here characterise ISAV-erythrocyte interactions in experimentally infected Atlantic salmon and show that ISAV-binding to erythrocytes is common and precedes the development of disease. Viral RNA and infective particles were enriched in the cellular fraction of blood. While erythrocyte-associated ISAV remained infectious, erythrocytes dose-dependently limited the infection of cultured cells. Surprisingly, immunostaining of blood smears revealed expression of ISAV proteins in a small fraction of erythrocytes in one of the examined trials, confirming that ISAV can be internalised in this cell type and engage the cellular machinery in transcription and translation. However, viral protein expression in erythrocytes was rare and not required for development of disease and mortality. Furthermore, active transcription of ISAV mRNA was higher in tissues than in blood, supporting the assumption that ISAV replication predominantly takes place in endothelial cells. In conclusion, Atlantic salmon erythrocytes bind ISAV and sequester infective virus particles during infection, but do not appear to significantly contribute to ISAV replication. We discuss the implications of our findings for infection dynamics and pathogenesis of infectious salmon anaemia.
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Affiliation(s)
- Johanna Hol Fosse
- Norwegian Veterinary Institute, 1433 Ås, Norway; (M.A.); (T.S.); (S.C.W.); (A.S.); (M.M.A.); (I.A.H.); (K.F.)
- Correspondence: ; Tel.: +47-9588-6639
| | - Maria Aamelfot
- Norwegian Veterinary Institute, 1433 Ås, Norway; (M.A.); (T.S.); (S.C.W.); (A.S.); (M.M.A.); (I.A.H.); (K.F.)
| | - Tonje Sønstevold
- Norwegian Veterinary Institute, 1433 Ås, Norway; (M.A.); (T.S.); (S.C.W.); (A.S.); (M.M.A.); (I.A.H.); (K.F.)
| | - Simon Chioma Weli
- Norwegian Veterinary Institute, 1433 Ås, Norway; (M.A.); (T.S.); (S.C.W.); (A.S.); (M.M.A.); (I.A.H.); (K.F.)
| | - Niccolò Vendramin
- Unit for Fish and Shellfish Diseases, National Institute of Aquatic Resources, Technical University of Denmark, 2800 Kongens Lyngby, Denmark; (N.V.); (A.C.)
| | - Petra Elisabeth Petersen
- National Reference Laboratory for Fish and Animal Diseases, Faroese Food and Veterinary Authority, 110 Tórshavn, Faroe Islands; (P.E.P.); (D.H.C.)
| | - Anita Solhaug
- Norwegian Veterinary Institute, 1433 Ås, Norway; (M.A.); (T.S.); (S.C.W.); (A.S.); (M.M.A.); (I.A.H.); (K.F.)
| | - Marit Måsøy Amundsen
- Norwegian Veterinary Institute, 1433 Ås, Norway; (M.A.); (T.S.); (S.C.W.); (A.S.); (M.M.A.); (I.A.H.); (K.F.)
| | - Inger Austrheim Heffernan
- Norwegian Veterinary Institute, 1433 Ås, Norway; (M.A.); (T.S.); (S.C.W.); (A.S.); (M.M.A.); (I.A.H.); (K.F.)
| | - Argelia Cuenca
- Unit for Fish and Shellfish Diseases, National Institute of Aquatic Resources, Technical University of Denmark, 2800 Kongens Lyngby, Denmark; (N.V.); (A.C.)
| | - Debes Hammershaimb Christiansen
- National Reference Laboratory for Fish and Animal Diseases, Faroese Food and Veterinary Authority, 110 Tórshavn, Faroe Islands; (P.E.P.); (D.H.C.)
| | - Knut Falk
- Norwegian Veterinary Institute, 1433 Ås, Norway; (M.A.); (T.S.); (S.C.W.); (A.S.); (M.M.A.); (I.A.H.); (K.F.)
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Christiansen DH, Petersen PE, Dahl MM, Vest N, Aamelfot M, Kristoffersen AB, Jansen MD, Matejusova I, Gallagher MD, Jónsson G, Rodriguez E, Fosse JH, Falk K. No Evidence of the Vertical Transmission of Non-Virulent Infectious Salmon Anaemia Virus (ISAV-HPR0) in Farmed Atlantic Salmon. Viruses 2021; 13:v13122428. [PMID: 34960697 PMCID: PMC8708482 DOI: 10.3390/v13122428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 11/30/2022] Open
Abstract
The nonvirulent infectious salmon anaemia virus (ISAV-HPR0) is the putative progenitor for virulent-ISAV, and a potential risk factor for the development of infectious salmon anaemia (ISA). Understanding the transmission dynamics of ISAV-HPR0 is fundamental to proper management and mitigation strategies. Here, we demonstrate that ISAV-HPR0 causes prevalent and transient infections in all three production stages of Atlantic salmon in the Faroe Islands. Phylogenetic analysis of the haemagglutinin-esterase gene from 247 salmon showed a clear geographical structuring into two significantly distinct HPR0-subgroups, which were designated G2 and G4. Whereas G2 and G4 co-circulated in marine farms, Faroese broodfish were predominantly infected by G2, and smolt were predominantly infected by G4. This infection pattern was confirmed by our G2- and G4-specific RT-qPCR assays. Moreover, the HPR0 variants detected in Icelandic and Norwegian broodfish were never detected in the Faroe Islands, despite the extensive import of ova from both countries. Accordingly, the vertical transmission of HPR0 from broodfish to progeny is uncommon. Phylogenetic and statistical analysis suggest that HPR0 persists in the smolt farms as “house-strains”, and that new HPR0 variants are occasionally introduced from the marine environment, probably by HPR0-contaminated sea-spray. Thus, high biosecurity—including water and air intake—is required to avoid the introduction of pathogens to the smolt farms.
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Affiliation(s)
- Debes Hammershaimb Christiansen
- National Reference Laboratory for Fish and Animal Diseases, Faroese Food and Veterinary Authority, 110 Torshavn, Faroe Islands; (P.E.P.); (M.M.D.); (N.V.)
- Correspondence:
| | - Petra Elisabeth Petersen
- National Reference Laboratory for Fish and Animal Diseases, Faroese Food and Veterinary Authority, 110 Torshavn, Faroe Islands; (P.E.P.); (M.M.D.); (N.V.)
| | - Maria Marjunardóttir Dahl
- National Reference Laboratory for Fish and Animal Diseases, Faroese Food and Veterinary Authority, 110 Torshavn, Faroe Islands; (P.E.P.); (M.M.D.); (N.V.)
| | - Nicolina Vest
- National Reference Laboratory for Fish and Animal Diseases, Faroese Food and Veterinary Authority, 110 Torshavn, Faroe Islands; (P.E.P.); (M.M.D.); (N.V.)
| | - Maria Aamelfot
- Norwegian Veterinary Institute, 0454 Oslo, Norway; (M.A.); (A.B.K.); (M.D.J.); (J.H.F.); (K.F.)
| | | | - Mona Dverdal Jansen
- Norwegian Veterinary Institute, 0454 Oslo, Norway; (M.A.); (A.B.K.); (M.D.J.); (J.H.F.); (K.F.)
| | - Iveta Matejusova
- Marine Scotland Science, Marine Laboratory, Aberdeen AB11 9DB, UK;
| | - Michael D. Gallagher
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh EH8 9YL, UK;
| | - Gísli Jónsson
- Icelandic Food and Veterinary Authority, 220 Hafnarfjordur, Iceland;
| | | | - Johanna Hol Fosse
- Norwegian Veterinary Institute, 0454 Oslo, Norway; (M.A.); (A.B.K.); (M.D.J.); (J.H.F.); (K.F.)
| | - Knut Falk
- Norwegian Veterinary Institute, 0454 Oslo, Norway; (M.A.); (A.B.K.); (M.D.J.); (J.H.F.); (K.F.)
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9
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Sander S, Ebert T, Hartnagel D, Hesse M, Pan X, Schaumann G, Šmíd M, Falk K, Roth M. Microstructured layered targets for improved laser-induced x-ray backlighters. Phys Rev E 2021; 104:065207. [PMID: 35030937 DOI: 10.1103/physreve.104.065207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 12/08/2021] [Indexed: 06/14/2023]
Abstract
We present the usage of two-layer targets with laser-illuminated front-side microstructures for x-ray backlighter applications. The targets consisted of a silicon front layer and copper back side layer. The structured layer was irradiated by the 500-fs PHELIX laser with an intensity above 10^{20}Wcm^{-2}. The total emission and one-dimensional extent of the copper Kα x-ray emission as well as a wide spectral range between 7.9 and 9.0 keV were recorded with an array of crystal spectrometers. The measurements show that the front-side modifications of the silicon in the form of conical microstructures maintain the same peak brightness of the Kα emission as flat copper foils while suppressing the thermal emission background significantly. The observed Kα source sizes can be influenced by tilting the conical microstructures with respect to the laser axis. Overall, the recorded copper Kα photon yields were in the range of 10^{11}sr^{-1}, demonstrating the suitability of these targets for probing applications without subjecting the probed material to additional heating from thermal line emission.
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Affiliation(s)
- S Sander
- Institut für Kernphysik, Fachbereich Physik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - T Ebert
- Institut für Kernphysik, Fachbereich Physik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - D Hartnagel
- Institut für Kernphysik, Fachbereich Physik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - M Hesse
- Institut für Kernphysik, Fachbereich Physik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - X Pan
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
- Technische Universität Dresden, 01062 Dresden, Germany
| | - G Schaumann
- Institut für Kernphysik, Fachbereich Physik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - M Šmíd
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - K Falk
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
- Technische Universität Dresden, 01062 Dresden, Germany
- Institute of Physics of the ASCR, 182 21 Prague, Czech Republic
| | - M Roth
- Institut für Kernphysik, Fachbereich Physik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
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10
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Alarcón M, Moldal T, Dverdal Jansen M, Aamelfot M, Sindre H, Lyngstad TM, Falk K. Infectious salmon anaemia virus detected by RT-qPCR in Norwegian farmed rainbow trout, Oncorhynchus mykiss (Walbaum, 1792). J Fish Dis 2021; 44:479-481. [PMID: 33284992 DOI: 10.1111/jfd.13315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/14/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Affiliation(s)
- Marta Alarcón
- Norwegian Veterinary Institute, Oslo, Norway
- Fish Vet Group, Benchmark Norway AS, Norway
| | | | | | - Maria Aamelfot
- Norwegian Veterinary Institute, Oslo, Norway
- Norwegian Institute of Public Health, Oslo, Norway
| | | | - Trude M Lyngstad
- Norwegian Veterinary Institute, Oslo, Norway
- Norwegian Institute of Public Health, Oslo, Norway
| | - Knut Falk
- Norwegian Veterinary Institute, Oslo, Norway
- AkvaMed Consulting AS, Oslo, Norway
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Abstract
There are several reasons to consider the role of endothelial cells in COVID-19 and other emerging viral infections. First, severe cases of COVID-19 show a common breakdown of central vascular functions. Second, SARS-CoV-2 replicates in endothelial cells. Third, prior deterioration of vascular function exacerbates disease, as the most common comorbidities of COVID-19 (obesity, hypertension, and diabetes) are all associated with endothelial dysfunction. Importantly, SARS-CoV-2's ability to infect endothelium is shared by many emerging viruses, including henipaviruses, hantavirus, and highly pathogenic avian influenza virus, all specifically targeting endothelial cells. The ability to infect endothelium appears to support generalised dissemination of infection and facilitate the access to certain tissues. The disturbed vascular function observed in severe COVID-19 is also a prominent feature of many other life-threatening viral diseases, underscoring the need to understand how viruses modulate endothelial function. We here review the role of vascular endothelial cells in emerging viral infections, starting with a summary of endothelial cells as key mediators and regulators of vascular and immune responses in health and infection. Next, we discuss endotheliotropism as a possible virulence factor and detail features that regulate viruses' ability to attach to and enter endothelial cells. We move on to review how endothelial cells detect invading viruses and respond to infection, with particular focus on pathways that may influence vascular function and the host immune system. Finally, we discuss how endothelial cell function can be dysregulated in viral disease, either by viral components or as bystander victims of overshooting or detrimental inflammatory and immune responses. Many aspects of how viruses interact with the endothelium remain poorly understood. Considering the diversity of such mechanisms among different emerging viruses allows us to highlight common features that may be of general validity and point out important challenges.
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Affiliation(s)
| | - Guttorm Haraldsen
- Department of Pathology, Oslo University Hospital, Oslo, Norway.,Department of Pathology, University of Oslo, Oslo, Norway
| | - Knut Falk
- Norwegian Veterinary Institute, Oslo, Norway.,AquaMed Consulting AS, Oslo, Norway
| | - Reidunn Edelmann
- Department of Clinical Medicine, Centre for Cancer Biomarkers CCBIO, University of Bergen, Bergen, Norway
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12
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Falk K, Holec M, Fontes CJ, Fryer CL, Greeff CW, Johns HM, Montgomery DS, Schmidt DW, Šmíd M. Erratum: Measurement of Preheat Due to Nonlocal Electron Transport in Warm Dense Matter [Phys. Rev. Lett. 120, 025002 (2018)]. Phys Rev Lett 2020; 124:159901. [PMID: 32357038 DOI: 10.1103/physrevlett.124.159901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 04/03/2020] [Indexed: 06/11/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.120.025002.
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13
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Youngstrom M, Metcalfe N, Falk K, Ogorek J, Chahine E. 73: Laparoscopic uterosacral ligament suspension task trainer. Am J Obstet Gynecol 2020. [DOI: 10.1016/j.ajog.2019.12.222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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14
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Kettle B, Gerstmayr E, Streeter MJV, Albert F, Baggott RA, Bourgeois N, Cole JM, Dann S, Falk K, Gallardo González I, Hussein AE, Lemos N, Lopes NC, Lundh O, Ma Y, Rose SJ, Spindloe C, Symes DR, Šmíd M, Thomas AGR, Watt R, Mangles SPD. Single-Shot Multi-keV X-Ray Absorption Spectroscopy Using an Ultrashort Laser-Wakefield Accelerator Source. Phys Rev Lett 2019; 123:254801. [PMID: 31922780 DOI: 10.1103/physrevlett.123.254801] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 10/16/2019] [Indexed: 06/10/2023]
Abstract
Single-shot absorption measurements have been performed using the multi-keV x rays generated by a laser-wakefield accelerator. A 200 TW laser was used to drive a laser-wakefield accelerator in a mode which produced broadband electron beams with a maximum energy above 1 GeV and a broad divergence of ≈15 mrad FWHM. Betatron oscillations of these electrons generated 1.2±0.2×10^{6} photons/eV in the 5 keV region, with a signal-to-noise ratio of approximately 300∶1. This was sufficient to allow high-resolution x-ray absorption near-edge structure measurements at the K edge of a titanium sample in a single shot. We demonstrate that this source is capable of single-shot, simultaneous measurements of both the electron and ion distributions in matter heated to eV temperatures by comparison with density functional theory simulations. The unique combination of a high-flux, large bandwidth, few femtosecond duration x-ray pulse synchronized to a high-power laser will enable key advances in the study of ultrafast energetic processes such as electron-ion equilibration.
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Affiliation(s)
- B Kettle
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, United Kingdom
| | - E Gerstmayr
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, United Kingdom
| | - M J V Streeter
- Physics Department, Lancaster University, Lancaster LA1 4YB, United Kingdom
| | - F Albert
- Lawrence Livermore National Laboratory (LLNL), Livermore, California 94550, USA
| | - R A Baggott
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, United Kingdom
| | - N Bourgeois
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - J M Cole
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, United Kingdom
| | - S Dann
- Physics Department, Lancaster University, Lancaster LA1 4YB, United Kingdom
| | - K Falk
- Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
- Institute of Physics of the ASCR, Na Slovance 1999/2, 182 21 Prague, Czech Republic
- Technische Universität Dresden, 01062, Dresden, Germany
| | | | - A E Hussein
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109-2099, USA
| | - N Lemos
- Lawrence Livermore National Laboratory (LLNL), Livermore, California 94550, USA
| | - N C Lopes
- GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, U.L., Lisboa 1049-001, Portugal
| | - O Lundh
- Department of Physics, Lund University, P.O. Box 118, S-22100, Lund, Sweden
| | - Y Ma
- Physics Department, Lancaster University, Lancaster LA1 4YB, United Kingdom
| | - S J Rose
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, United Kingdom
| | - C Spindloe
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - D R Symes
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot OX11 0QX, United Kingdom
| | - M Šmíd
- Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - A G R Thomas
- Physics Department, Lancaster University, Lancaster LA1 4YB, United Kingdom
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109-2099, USA
| | - R Watt
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, United Kingdom
| | - S P D Mangles
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, United Kingdom
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15
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Hussein AE, Senabulya N, Ma Y, Streeter MJV, Kettle B, Dann SJD, Albert F, Bourgeois N, Cipiccia S, Cole JM, Finlay O, Gerstmayr E, González IG, Higginbotham A, Jaroszynski DA, Falk K, Krushelnick K, Lemos N, Lopes NC, Lumsdon C, Lundh O, Mangles SPD, Najmudin Z, Rajeev PP, Schlepütz CM, Shahzad M, Smid M, Spesyvtsev R, Symes DR, Vieux G, Willingale L, Wood JC, Shahani AJ, Thomas AGR. Laser-wakefield accelerators for high-resolution X-ray imaging of complex microstructures. Sci Rep 2019; 9:3249. [PMID: 30824838 PMCID: PMC6397215 DOI: 10.1038/s41598-019-39845-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 01/29/2019] [Indexed: 12/19/2022] Open
Abstract
Laser-wakefield accelerators (LWFAs) are high acceleration-gradient plasma-based particle accelerators capable of producing ultra-relativistic electron beams. Within the strong focusing fields of the wakefield, accelerated electrons undergo betatron oscillations, emitting a bright pulse of X-rays with a micrometer-scale source size that may be used for imaging applications. Non-destructive X-ray phase contrast imaging and tomography of heterogeneous materials can provide insight into their processing, structure, and performance. To demonstrate the imaging capability of X-rays from an LWFA we have examined an irregular eutectic in the aluminum-silicon (Al-Si) system. The lamellar spacing of the Al-Si eutectic microstructure is on the order of a few micrometers, thus requiring high spatial resolution. We present comparisons between the sharpness and spatial resolution in phase contrast images of this eutectic alloy obtained via X-ray phase contrast imaging at the Swiss Light Source (SLS) synchrotron and X-ray projection microscopy via an LWFA source. An upper bound on the resolving power of 2.7 ± 0.3 μm of the LWFA source in this experiment was measured. These results indicate that betatron X-rays from laser wakefield acceleration can provide an alternative to conventional synchrotron sources for high resolution imaging of eutectics and, more broadly, complex microstructures.
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Affiliation(s)
- A E Hussein
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, MI, 48109-2099, USA.
| | - N Senabulya
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI, 48109-2099, USA
| | - Y Ma
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, MI, 48109-2099, USA.,Physics Department, Lancaster University, Lancaster, LA1 4YB, UK.,The Cockcroft Institute, Keckwick Lane, Daresbury, WA4 4AD, UK
| | - M J V Streeter
- Physics Department, Lancaster University, Lancaster, LA1 4YB, UK.,The Cockcroft Institute, Keckwick Lane, Daresbury, WA4 4AD, UK.,The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, UK
| | - B Kettle
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, UK
| | - S J D Dann
- Physics Department, Lancaster University, Lancaster, LA1 4YB, UK.,The Cockcroft Institute, Keckwick Lane, Daresbury, WA4 4AD, UK
| | - F Albert
- Lawrence Livermore National Laboratory, NIF and Photon Sciences, Livermore, CA, 94550, USA
| | - N Bourgeois
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot, OX11 0QX, UK
| | - S Cipiccia
- Diamond Light Source, Harwell Science and Innovation Campus, Fermi Avenue, Didcot, OX11 0DE, UK
| | - J M Cole
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, UK
| | - O Finlay
- Physics Department, Lancaster University, Lancaster, LA1 4YB, UK.,The Cockcroft Institute, Keckwick Lane, Daresbury, WA4 4AD, UK
| | - E Gerstmayr
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, UK
| | | | - A Higginbotham
- York Plasma Institute, Department of Physics, University of York, York, YO10 5DD, UK
| | - D A Jaroszynski
- The Cockcroft Institute, Keckwick Lane, Daresbury, WA4 4AD, UK.,SUPA, Department of Physics, University of Strathclyde, Glasgow, G4 0NG, UK
| | - K Falk
- Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01328, Dresden, Germany.,Technische Universität Dresden, 01062, Dresden, Germany.,Institute of Physics of the ASCR, 182 21, Prague, Czech Republic
| | - K Krushelnick
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, MI, 48109-2099, USA
| | - N Lemos
- Lawrence Livermore National Laboratory, NIF and Photon Sciences, Livermore, CA, 94550, USA
| | - N C Lopes
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, UK.,GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, U.L., Lisboa, 1049-001, Portugal
| | - C Lumsdon
- York Plasma Institute, Department of Physics, University of York, York, YO10 5DD, UK
| | - O Lundh
- Department of Physics, Lund University, P.O. Box 118, S-22100, Lund, Sweden
| | - S P D Mangles
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, UK
| | - Z Najmudin
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, UK
| | - P P Rajeev
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot, OX11 0QX, UK
| | - C M Schlepütz
- Swiss Light Source, Paul Scherrer Institute, CH-5232, Villigen, Switzerland
| | - M Shahzad
- The Cockcroft Institute, Keckwick Lane, Daresbury, WA4 4AD, UK.,SUPA, Department of Physics, University of Strathclyde, Glasgow, G4 0NG, UK
| | - M Smid
- Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01328, Dresden, Germany.,ELI Beamlines, Institute of Physics of the ASCR, 182 21, Prague, Czech Republic
| | - R Spesyvtsev
- The Cockcroft Institute, Keckwick Lane, Daresbury, WA4 4AD, UK.,SUPA, Department of Physics, University of Strathclyde, Glasgow, G4 0NG, UK
| | - D R Symes
- Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot, OX11 0QX, UK
| | - G Vieux
- The Cockcroft Institute, Keckwick Lane, Daresbury, WA4 4AD, UK.,SUPA, Department of Physics, University of Strathclyde, Glasgow, G4 0NG, UK
| | - L Willingale
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, MI, 48109-2099, USA
| | - J C Wood
- The John Adams Institute for Accelerator Science, Imperial College London, London, SW7 2AZ, UK
| | - A J Shahani
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI, 48109-2099, USA
| | - A G R Thomas
- Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, MI, 48109-2099, USA.,Physics Department, Lancaster University, Lancaster, LA1 4YB, UK.,The Cockcroft Institute, Keckwick Lane, Daresbury, WA4 4AD, UK
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16
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Gudo ES, Ali S, António VS, Chelene IR, Chongo I, Demanou M, Falk K, Guiliche OC, Heinrich N, Monteiro V, Muianga AF, Oludele J, Mula F, Mutuku F, Amade N, Alho P, Betsem E, Chimbuinhe Z, Cristovam AJ, Galano G, Gessain A, Harris E, Heise M, Inalda F, Jala I, Jaszi E, King C, Kitron U, Kümmerer BM, LaBeaud AD, Lagerqvist N, Malai G, Mazelier M, Mendes S, Mukoko D, Ndenga B, Njouom R, Pinto G, Tivane A, Vu DM, Vulule J. Seroepidemiological Studies of Arboviruses in Africa. Adv Exp Med Biol 2018; 1062:361-371. [PMID: 29845545 DOI: 10.1007/978-981-10-8727-1_25] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
The literature on sero-epidemiological studies of flaviviral infections in the African continent is quite scarce. Much of the viral epidemiology studies have been focussing on diseases such as HIV/AIDS because of their sheer magnitude and impact on the lives of people in the various affected countries. Increasingly disease outbreaks caused by arboviruses such as the recent cases of chikungunya virus, dengue virus and yellow fever virus have prompted renewed interest in studying these viruses. International agencies from the US, several EU nations and China are starting to build collaborations to build capacity in many African countries together with established institutions to conduct these studies. The Tofo Advanced Study Week (TASW) was established to bring the best scientists from the world to the tiny seaside town of Praia do Tofo to rub shoulders with African virologists and discuss cutting-edge science and listen to the work of researchers in the field. In 2015 the 1st TASW focussed on Ebola virus. The collections of abstracts from participants at the 2nd TASW which focused on Dengue and Zika virus as well as presentations on other arboviruses are collated in this chapter.
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Affiliation(s)
| | - S Ali
- National Institute of Health, Maputo, Mozambique
| | - V S António
- National Institute of Health, Maputo, Mozambique
| | - I R Chelene
- National Institute of Health, Maputo, Mozambique
| | - I Chongo
- National Institute of Health, Maputo, Mozambique
| | - M Demanou
- Laboratoire des arbovirus et des virus de fièvres hémorragiques, Centre Pasteur du Cameroun (CPC), Yaoundé, Cameroon.
| | - K Falk
- The Public Health Agency of Sweden and Karolinska Institute, Solna, Sweden.
| | - O C Guiliche
- National Institute of Health, Maputo, Mozambique
| | - N Heinrich
- Infectious Diseases & Tropical Medicine, Medical Center of the University of Munich (LMU), Munich, Germany.
| | - V Monteiro
- National Institute of Health, Maputo, Mozambique
| | - A F Muianga
- National Institute of Health, Maputo, Mozambique
| | - J Oludele
- National Institute of Health, Maputo, Mozambique
| | - F Mula
- National Institute of Health, Maputo, Mozambique
| | - F Mutuku
- Technical University of Mombasa, Mombasa, Kenya.
| | - N Amade
- National Institute of Health, Maputo, Mozambique
| | - P Alho
- National Institute of Health, Maputo, Mozambique
| | - E Betsem
- Faculté de médecine et des Sciences Biomédicales, Université de Yaoundé 1, Yaoundé, Cameroon
- Unité d'Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France
| | | | | | - G Galano
- Pemba Provincial Hospital, Pemba, Mozambique
| | - A Gessain
- Unité d'Epidémiologie et Physiopathologie des Virus Oncogènes, Institut Pasteur, Paris, France
| | - E Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, CA, USA
| | - M Heise
- University of North Carolina School of Medicine, Chapel Hill, NC, USA
| | - F Inalda
- National Institute of Health, Maputo, Mozambique
| | - I Jala
- Laboratoire des arbovirus et des virus de fièvres hémorragiques, Centre Pasteur du Cameroun (CPC), Yaoundé, Cameroon
- Tropical Disease Research Center (TDRC), Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - E Jaszi
- Centers for Disease Control and Prevention (CDC), Atlanta, GA, USA
| | - C King
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
| | - U Kitron
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
| | - B M Kümmerer
- Institute of Virology, University of Bonn Medical Centre, Bonn, Germany
| | - A D LaBeaud
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, OH, USA
- Department of Pediatrics, Division of Infectious Diseases, Stanford University School of Medicine, California, USA
| | - N Lagerqvist
- The Public Health Agency of Sweden and Karolinska Institute, Solna, Sweden
| | - G Malai
- Polana Caniço General Hospital Mozambique, Maputo, Mozambique
| | - M Mazelier
- Laboratoire des arbovirus et des virus de fièvres hémorragiques, Centre Pasteur du Cameroun (CPC), Yaoundé, Cameroon
| | - S Mendes
- Nampula Central Hospital, Nampula, Mozambique
| | - D Mukoko
- Department of Pediatrics, Division of Infectious Diseases, Stanford University School of Medicine, California, USA
| | - B Ndenga
- Centre for Global Health Research, Kenya Medical Research Institute, Nairobi, Kenya
| | - R Njouom
- Laboratoire des arbovirus et des virus de fièvres hémorragiques, Centre Pasteur du Cameroun (CPC), Yaoundé, Cameroon
| | - G Pinto
- National Institute of Health, Maputo, Mozambique
| | - A Tivane
- National Institute of Health, Maputo, Mozambique
| | - D M Vu
- Department of Pediatrics, Division of Infectious Diseases, Stanford University School of Medicine, California, USA
| | - J Vulule
- Centre for Global Health Research, Kenya Medical Research Institute, Nairobi, Kenya
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17
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Gallagher MD, Matejusova I, Nguyen L, Ruane NM, Falk K, Macqueen DJ. Nanopore sequencing for rapid diagnostics of salmonid RNA viruses. Sci Rep 2018; 8:16307. [PMID: 30397226 PMCID: PMC6218516 DOI: 10.1038/s41598-018-34464-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 10/19/2018] [Indexed: 12/16/2022] Open
Abstract
Analysis of pathogen genome variation is essential for informing disease management and control measures in farmed animals. For farmed fish, the standard approach is to use PCR and Sanger sequencing to study partial regions of pathogen genomes, with second and third-generation sequencing tools yet to be widely applied. Here we demonstrate rapid and accurate sequencing of two disease-causing viruses affecting global salmonid aquaculture, salmonid alphavirus (SAV) and infectious salmon anaemia virus (ISAV), using third-generation nanopore sequencing on the MinION platform (Oxford Nanopore Technologies). Our approach complements PCR from infected material with MinION sequencing to recover genomic information that matches near perfectly to Sanger-verified references. We use this method to present the first SAV subtype-6 genome, which branches as the sister to all other SAV lineages in a genome-wide phylogenetic reconstruction. MinION sequencing offers an effective strategy for fast, genome-wide analysis of fish viruses, with major potential applications for diagnostics and robust investigations into the origins and spread of disease outbreaks.
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Affiliation(s)
- Michael D Gallagher
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, United Kingdom
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Midlothian, EH25 9RG, United Kingdom
| | - Iveta Matejusova
- Marine Scotland Science, Marine Laboratory, Aberdeen, AB11 9DB, United Kingdom
| | - Lien Nguyen
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, United Kingdom
| | - Neil M Ruane
- Fish Health Unit, Marine Institute, Rinville Oranmore, Co, Galway, Ireland
| | - Knut Falk
- Norwegian Veterinary Institute, Ullevålsveien 68, 0454, Oslo, Norway
| | - Daniel J Macqueen
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, United Kingdom.
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Midlothian, EH25 9RG, United Kingdom.
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18
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Falk K, Holec M, Fontes CJ, Fryer CL, Greeff CW, Johns HM, Montgomery DS, Schmidt DW, Šmíd M. Measurement of Preheat Due to Nonlocal Electron Transport in Warm Dense Matter. Phys Rev Lett 2018; 120:025002. [PMID: 29376698 DOI: 10.1103/physrevlett.120.025002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 08/23/2017] [Indexed: 06/07/2023]
Abstract
This Letter presents a novel approach to study electron transport in warm dense matter. It also includes the first x-ray Thomson scattering (XRTS) measurement from low-density CH foams compressed by a strong laser-driven shock at the OMEGA laser facility. The XRTS measurement is combined with velocity interferometry (VISAR) and optical pyrometry (SOP) providing a robust measurement of thermodynamic conditions in the shock. Evidence of significant preheat contributing to elevated temperatures reaching 17.5-35 eV in shocked CH foam is measured by XRTS. These measurements are complemented by abnormally high shock velocities observed by VISAR and early emission seen by SOP. These results are compared to radiation hydrodynamics simulations that include first-principles treatment of nonlocal electron transport in warm dense matter with excellent agreement. Additional simulations confirm that the x-ray contribution to this preheat is negligible.
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Affiliation(s)
- K Falk
- Institute of Physics of the ASCR, ELI-Beamlines, 182 21 Prague, Czech Republic
| | - M Holec
- Institute of Physics of the ASCR, ELI-Beamlines, 182 21 Prague, Czech Republic
- Centre Lasers Intenses et Applications, Universite de Bordeaux-CNRS-CEA, UMR 5107, F-33405 Talence, France
- Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, 120 00 Prague 1, Czech Republic
| | - C J Fontes
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - C L Fryer
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - C W Greeff
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - H M Johns
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - D S Montgomery
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - D W Schmidt
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - M Šmíd
- Institute of Physics of the ASCR, ELI-Beamlines, 182 21 Prague, Czech Republic
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19
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Aas IB, Austbø L, Falk K, Hordvik I, Koppang EO. The interbranchial lymphoid tissue likely contributes to immune tolerance and defense in the gills of Atlantic salmon. Dev Comp Immunol 2017; 76:247-254. [PMID: 28655579 DOI: 10.1016/j.dci.2017.06.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 06/22/2017] [Accepted: 06/23/2017] [Indexed: 06/07/2023]
Abstract
Central and peripheral immune tolerance is together with defense mechanisms a hallmark of all lymphoid tissues. In fish, such tolerance is especially important in the gills, where the intimate contact between gill tissue and the aqueous environment would otherwise lead to continual immune stimulation by innocuous antigens. In this paper, we focus on the expression of genes associated with immune regulation by the interbranchial lymphoid tissue (ILT) in an attempt to understand its role in maintaining immune homeostasis. Both healthy and virus-challenged fish were investigated, and transcript levels were examined from laser-dissected ILT, gills, head kidney and intestine. Lack of Aire expression in the ILT excluded its involvement in central tolerance and any possibility of its being an analogue to the thymus. On the other hand, the ILT appears to participate in peripheral immune tolerance due to its relatively high expression of forkhead box protein 3 (Foxp3) and other genes associated with regulatory T cells (Tregs) and immune suppression.
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Affiliation(s)
- Ida Bergva Aas
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Lars Austbø
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Knut Falk
- Norwegian Veterinary Institute, 0454 Oslo, Norway
| | - Ivar Hordvik
- Department of Biology, High Technology Centre, University of Bergen, 5006 Bergen, Norway
| | - Erling Olaf Koppang
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 0454 Oslo, Norway.
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20
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Weli SC, Dale OB, Hansen H, Gjessing MC, Rønneberg LB, Falk K. A case study of Desmozoon lepeophtherii infection in farmed Atlantic salmon associated with gill disease, peritonitis, intestinal infection, stunted growth, and increased mortality. Parasit Vectors 2017; 10:370. [PMID: 28764744 PMCID: PMC5540559 DOI: 10.1186/s13071-017-2303-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 07/20/2017] [Indexed: 11/25/2022] Open
Abstract
Background In September 2008, a disease outbreak characterized by acute, severe gill pathology and peritonitis, involving the gastrointestinal tract, was observed in an Atlantic salmon (Salmo salar L.) farm in north-western Norway. During subsequent sampling in November 2008 and January 2009, chronic proliferative gill inflammation and peritonitis was observed. Cumulative mortalities of 5.6–12.8% and severe growth retardation were observed. Routine diagnostic analysis revealed no diseases known to salmon at the time, but microsporidian infection of tissues was observed. Methods To characterize the disease outbreak, a combination of histopathology, in situ hybridization (ISH), chitin, calcofluor-white (CFW) staining, and real-time PCR were used to describe the disease progression with visualization of the D. lepeophtherii stages in situ. Results The presence of the microsporidian Desmozoon lepeophtherii was confirmed with real-time PCR, DNA sequencing and ISH, and the parasite was detected in association with acute lesions in the gills and peritoneum. ISH using a probe specific to small subunit 16S rRNA gene provided an effective tool for demonstrating the distribution of D. lepeophtherii in the tissue. Infection in the peritoneum seemed localized in and around pre-existing vaccine granulomas, and in the gastrointestinal walls. In the heart, kidney and spleen, the infection was most often associated with mononuclear leucocytes and macrophages, including melanomacrophages. Desmozoon lepeophtherii exospores were found in the nuclei of the gastrointestinal epithelium for the first time, suggesting a role of the gastrointestinal tract in the spread of spores to the environment. Conclusions This study describes the progression of D. lepeophtherii disease outbreak in an Atlantic salmon farm without any other known diseases present. Using different methods to examine the disease outbreak, new insight into the pathology of D. lepeophtherii was obtained. The parasite was localized in situ in association with severe tissue damage and inflammation in the gills, peritoneal cavity and in the gastrointestinal (GI) tract that links the parasite directly to the observed pathology.
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Affiliation(s)
- Simon Chioma Weli
- Norwegian Veterinary Institute, P.O.Box 750 Dep., N-0106, Oslo, Norway
| | - Ole Bendik Dale
- Norwegian Veterinary Institute, P.O.Box 750 Dep., N-0106, Oslo, Norway.
| | - Haakon Hansen
- Norwegian Veterinary Institute, P.O.Box 750 Dep., N-0106, Oslo, Norway
| | | | - Liv Birte Rønneberg
- Present address: Fiske-liv AS, Marine Harvest Apotekergt. 9A, 6004, Ålesund, Norway
| | - Knut Falk
- Norwegian Veterinary Institute, P.O.Box 750 Dep., N-0106, Oslo, Norway
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Christiansen DH, McBeath AJA, Aamelfot M, Matejusova I, Fourrier M, White P, Petersen PE, Falk K. First field evidence of the evolution from a non-virulent HPR0 to a virulent HPR-deleted infectious salmon anaemia virus. J Gen Virol 2017; 98:595-606. [PMID: 28475029 DOI: 10.1099/jgv.0.000741] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The putatively non-virulent subtype of infectious salmon anaemia virus (ISAV), ISAV-HPR0, is proposed to act as a progenitor and reservoir for all virulent ISAVs and thus represent a potential risk factor for the emergence of infectious salmon anaemia (ISA) disease. Here, we provide the first evidence of genetic and functional evolution from an ISAV-HPR0 variant (FO/07/12) to a low-virulent ISAV virus (FO/121/14) in a Faroese Atlantic salmon marine farm. The FO/121/14 virus infection was not associated with specific clinical signs of ISA and was confined to a single net-pen, while various ISAV-HPR0 subtypes were found circulating in most epidemiologically linked marine and freshwater farms. Sequence analysis of all eight segments revealed that the FO/121/14 virus was identical, apart from a substitution in the fusion (F) gene (Q266L) and a deletion in the haemagglutinin-esterase (HE) gene, to the FO/07/12 variant from a freshwater farm, which supplied smolts exclusively to the FO/121/14-positive net-pen. An immersion challenge with the FO/121/14 virus induced a systemic infection in Atlantic salmon associated with a low mortality and mild clinical signs confirming its low pathogenicity. Our results demonstrate that mutations in the F protein and deletions in the highly polymorphic region (HPR) of the HE protein represent a minimum requirement for ISAV to gain virulence and to switch cell tropism from a localized epithelial infection to a systemic endotheliotropic infection. This documents that ISAV-HPR0 represents a reservoir and risk factor for the emergence of ISA disease.
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Affiliation(s)
- Debes H Christiansen
- Faroese Food and Veterinary Authority, National Reference Laboratory for Fish Diseases, Tórshavn, Faroe Islands
| | | | | | | | | | - Patricia White
- Marine Scotland Science, Marine Laboratory, Aberdeen, Scotland
| | - Petra E Petersen
- Faroese Food and Veterinary Authority, National Reference Laboratory for Fish Diseases, Tórshavn, Faroe Islands
| | - Knut Falk
- Norwegian Veterinary Institute, Oslo, Norway
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Šmíd M, Gallardo González I, Ekerfelt H, Björklund Svensson J, Hansson M, Wood JC, Persson A, Mangles SPD, Lundh O, Falk K. Highly efficient angularly resolving x-ray spectrometer optimized for absorption measurements with collimated sources. Rev Sci Instrum 2017; 88:063102. [PMID: 28667973 DOI: 10.1063/1.4986464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Highly collimated betatron radiation from a laser wakefield accelerator is a promising tool for spectroscopic measurements. Therefore, there is a requirement to create spectrometers suited to the unique properties of such a source. We demonstrate a spectrometer which achieves an energy resolution of <5 eV at 9 keV (E∕ΔE>1800) and is angularly resolving the x-ray emission allowing the reference and spectrum to be recorded at the same time. The single photon analysis is used to significantly reduce the background noise. Theoretical performance of various configurations of the spectrometer is calculated by a ray-tracing algorithm. The properties and performance of the spectrometer including the angular and spectral resolution are demonstrated experimentally on absorption above the K-edge of a Cu foil backlit by a laser-produced betatron radiation x-ray beam.
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Affiliation(s)
- M Šmíd
- Institute of Physics of the ASCR, ELI-Beamlines, 18221 Prague, Czech Republic
| | | | - H Ekerfelt
- Department of Physics, Lund University, P.O. Box 118, S-22100 Lund, Sweden
| | | | - M Hansson
- Department of Physics, Lund University, P.O. Box 118, S-22100 Lund, Sweden
| | - J C Wood
- John Adams Institute for Accelerator Science, Imperial College London, SW7 2AZ London, United Kingdom
| | - A Persson
- Department of Physics, Lund University, P.O. Box 118, S-22100 Lund, Sweden
| | - S P D Mangles
- John Adams Institute for Accelerator Science, Imperial College London, SW7 2AZ London, United Kingdom
| | - O Lundh
- Department of Physics, Lund University, P.O. Box 118, S-22100 Lund, Sweden
| | - K Falk
- Institute of Physics of the ASCR, ELI-Beamlines, 18221 Prague, Czech Republic
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Kammerer K, Falk K, Heintze C, Döpfmer S, Heusinger J. [GPs' Views on Barriers and Preconditions for Referring Elderly People with Depressive Disorder to Psychotherapy]. Gesundheitswesen 2016; 81:58-62. [PMID: 27846669 DOI: 10.1055/s-0042-116589] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE Older people with depressive disorders access psychotherapy less frequently than younger ones. GPs play an important role in referring patients, particularly the elderly, to psychotherapeutic treatment. This paper presents the obstacles to and preconditions for referring older, depressed sick people to psychotherapy from the point of view of GPs. METHODOLOGY Doctors who are training GPs were given a questionnaire on the care of the elderly (60+) with depressive disorders. In 2 open questions, they were requested to state their views on obstacles to and preconditions for referring older, depressed diseased people to psychotherapeutic treatment. RESULTS Most statements related to obstacles perceived by patients followed by barriers on the part of the supply system. Especially obstructive attitudes and emotions, but also functional limitations on the part of patients were referred to as barriers. With regard to the supply system, structural aspects, such as lack of psychotherapy places, but also the actions of care providers and insufficient cooperation were listed. As preconditions, specific therapy for the elderly were mentioned CONCLUSIONS: Dealing with reservations about psychotherapy on the part of older people takes time, which usually is not reimbursed in general practice. Collaborations with psychotherapists are seen as an important precondition for referral. Especially for people with multiple illnesses, access is considered difficult.
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Affiliation(s)
- K Kammerer
- Institut für Gerontologische Forschung e. V., Berlin
| | - K Falk
- Institut für Gerontologische Forschung e. V., Berlin
| | - C Heintze
- Institut für Allgemeinmedizin der Charité-Universitätsmedizin Berlin
| | - S Döpfmer
- Institut für Allgemeinmedizin der Charité-Universitätsmedizin Berlin
| | - J Heusinger
- Hochschule Magdeburg-Stendal, Fachbereich Soziale Arbeit, Gesundheit und Medien - SGM
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Falk K, Andikyan V, Kolev V. Laparoscopic Resection of Para-Aortic Tumor Recurrence Using Kocher Maneuver Duodenal Mobilization. J Minim Invasive Gynecol 2016. [DOI: 10.1016/j.jmig.2016.08.417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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26
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Kammerer K, Falk K, Döpfmer S, Heintze C. [GPs' Perceptions of Strengths and Shortcomings of the ICD-10 for Diagnosis of depression]. Gesundheitswesen 2016; 80:40-42. [PMID: 27056710 DOI: 10.1055/s-0041-111840] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AIM For the health care of people with depressive disorders, general practitioners are important contact persons. Some investigations have shown an under-diagnosis of these patients in GPs' surgeries. The significance of the ICD-10 for the diagnosis of depression is disputed. The BMBF-funded study "PSYTIA - Psychotherapy in old age" engages, among others, with the treatment of older people with depression in GPs' surgeries. This study presents the strengths and shortcomings of the ICD-10 for diagnosis of depression from the point of view of GPs. METHODS With the help of a questionnaire, 402 teaching GPs were asked how they diagnose and treat elderly people (60+) with depressive disorders in their practices. The response rate was 23.6%. 2 open-ended questions dealt with GPs' perceptions of strengths and shortcomings of ICD-10 for the diagnosis of depression. The responses were matched to inductively developed overarching categories. RESULTS About three-quarters of the respondents answered the 2 questions. While nearly one-fifth of the respondents did not state any opinion about the suitability of ICD-10 as a diagnostic instrument for depressive disorders, 41% of the respondents mentioned the shortcomings and one-third the strengths of ICD-10. Shortcomings and strengths relate primarily to the complexity of the instrument and its manageability in everyday practice. CONCLUSIONS The results show that application of ICD-10 in a GP's surgery depends on a holistic, hermeneutical approach to the case in family practice, a need for efficient practice management, and billing. These different perceptions explain the heterogeneous and ambivalent assessment of the suitability of ICD-10 for the diagnosis of depression.
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Affiliation(s)
- K Kammerer
- Institut für Gerontologische Forschung e. V., Berlin
| | - K Falk
- Institut für Gerontologische Forschung e. V., Berlin
| | - S Döpfmer
- Institut für Allgemeinmedizin Charité, Universitätsmedizin Berlin
| | - C Heintze
- Institut für Allgemeinmedizin Charité, Universitätsmedizin Berlin
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27
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Muianga A, Falk K, Oludele J, Pinto G, Ali S, Tivane A, Galano G, Gudo ES, Lagerqvist N. Serological and molecular investigation of dengue, chikungunya and rift valey fever in febrile and non-febrile patients from northern Mozambique during Dengue outbreak, 2014. Int J Infect Dis 2016. [DOI: 10.1016/j.ijid.2016.02.430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Dalum A, Tangen R, Falk K, Hordvik I, Rosenlund G, Torstensen B, Koppang EO. Coronary changes in the Atlantic salmon Salmo salar L: characterization and impact of dietary fatty acid compositions. J Fish Dis 2016; 39:41-54. [PMID: 25413740 DOI: 10.1111/jfd.12321] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 09/11/2014] [Accepted: 09/15/2014] [Indexed: 06/04/2023]
Abstract
Consumption of fatty acids from fishes is widely regarded as beneficial for preventing cardiovascular disorders. Nevertheless, salmonids themselves are victims of vascular diseases. As the pathogenesis and nature of these changes are elusive, they are here addressed using novel morphological and transcriptional approaches. Coronary arteries of wild Atlantic salmon Salmo salar L., (n = 12) were investigated using histological and immunohistochemical techniques, and RT-qPCR was employed to investigate expression of stretch-induced genes. In an experimental trial, fish were fed diets with different fatty acids composition, and histological features of the coronary arteries (n = 36) were investigated. In addition, the heart fatty acid profile (n = 60) was analysed. There were no differences in morphological or immunological features between wild fish and groups of experimental fish. Arteriosclerotic lesions consisted of smooth muscle cells in dissimilar differential stages embedded in considerable amounts of extracellular matrix in a similar fashion to what is seen in early stages of human atherosclerosis. No fat accumulations were observed, and very few inflammatory cells were present. In affected arteries, there was an induction of stretch-related genes, pointing to a stress-related response. We suggest that salmon may have a natural resistance to developing atherosclerosis, which corresponds well with their high investment in lipid metabolism.
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Affiliation(s)
- A Dalum
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway
| | - R Tangen
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway
| | - K Falk
- Norwegian Veterinary Institute, Norway
| | - I Hordvik
- Institute of Biology, University of Bergen, Norway
| | | | - B Torstensen
- National Institute of Nutrition and Seafood Research (NIFES), Bergen, Norway
| | - E O Koppang
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway
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Kurath G, Winton JR, Dale OB, Purcell MK, Falk K, Busch RA. Atlantic salmon, Salmo salar L. are broadly susceptible to isolates representing the North American genogroups of infectious hematopoietic necrosis virus. J Fish Dis 2016; 39:55-67. [PMID: 25381936 DOI: 10.1111/jfd.12323] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 09/19/2014] [Accepted: 09/22/2014] [Indexed: 06/04/2023]
Abstract
Beginning in 1992, three epidemic waves of infectious hematopoietic necrosis, often with high mortality, occurred in farmed Atlantic salmon Salmo salar L. on the west coast of North America. We compared the virulence of eleven strains of infectious hematopoietic necrosis virus (IHNV), representing the U, M and L genogroups, in experimental challenges of juvenile Atlantic salmon in freshwater. All strains caused mortality and there was wide variation within genogroups: cumulative mortality for five U-group strains ranged from 20 to 100%, four M-group strains ranged 30-63% and two L-group strains varied from 41 to 81%. Thus, unlike Pacific salmonids, there was no apparent correlation of virulence in a particular host species with virus genogroup. The mortality patterns indicated two different phenotypes in terms of kinetics of disease progression and final per cent mortality, with nine strains having moderate virulence and two strains (from the U and L genogroups) having high virulence. These phenotypes were investigated by histopathology and immunohistochemistry to describe the variation in the course of IHNV disease in Atlantic salmon. The results from this study demonstrate that IHNV may become a major threat to farmed Atlantic salmon in other regions of the world where the virus has been, or may be, introduced.
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Affiliation(s)
- G Kurath
- U.S. Geological Survey, Western Fisheries Research Center, Seattle, WA, USA
| | - J R Winton
- U.S. Geological Survey, Western Fisheries Research Center, Seattle, WA, USA
| | - O B Dale
- Norwegian Veterinary Institute, Oslo, Norway
| | - M K Purcell
- U.S. Geological Survey, Western Fisheries Research Center, Seattle, WA, USA
| | - K Falk
- Norwegian Veterinary Institute, Oslo, Norway
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Fourrier M, Lester K, Markussen T, Falk K, Secombes CJ, McBeath A, Collet B. Dual Mutation Events in the Haemagglutinin-Esterase and Fusion Protein from an Infectious Salmon Anaemia Virus HPR0 Genotype Promote Viral Fusion and Activation by an Ubiquitous Host Protease. PLoS One 2015; 10:e0142020. [PMID: 26517828 PMCID: PMC4627773 DOI: 10.1371/journal.pone.0142020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 10/15/2015] [Indexed: 11/24/2022] Open
Abstract
In Infectious salmon anaemia virus (ISAV), deletions in the highly polymorphic region (HPR) in the near membrane domain of the haemagglutinin-esterase (HE) stalk, influence viral fusion. It is suspected that selected mutations in the associated Fusion (F) protein may also be important in regulating fusion activity. To better understand the underlying mechanisms involved in ISAV fusion, several mutated F proteins were generated from the Scottish Nevis and Norwegian SK779/06 HPR0. Co-transfection with constructs encoding HE and F were performed, fusion activity assessed by content mixing assay and the degree of proteolytic cleavage by western blot. Substitutions in Nevis F demonstrated that K276 was the most likely cleavage site in the protein. Furthermore, amino acid substitutions at three sites and two insertions, all slightly upstream of K276, increased fusion activity. Co-expression with HE harbouring a full-length HPR produced high fusion activities when trypsin and low pH were applied. In comparison, under normal culture conditions, groups containing a mutated HE with an HPR deletion were able to generate moderate fusion levels, while those with a full length HPR HE could not induce fusion. This suggested that HPR length may influence how the HE primes the F protein and promotes fusion activation by an ubiquitous host protease and/or facilitate subsequent post-cleavage refolding steps. Variations in fusion activity through accumulated mutations on surface glycoproteins have also been reported in other orthomyxoviruses and paramyxoviruses. This may in part contribute to the different virulence and tissue tropism reported for HPR0 and HPR deleted ISAV genotypes.
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Affiliation(s)
- Mickael Fourrier
- Aquaculture and Fish Health, Marine Scotland Science, Aberdeen, United Kingdom
- * E-mail:
| | - Katherine Lester
- Aquaculture and Fish Health, Marine Scotland Science, Aberdeen, United Kingdom
| | | | - Knut Falk
- Epidemiology, Norwegian Veterinary Institute, Oslo, Norway
| | | | - Alastair McBeath
- Aquaculture and Fish Health, Marine Scotland Science, Aberdeen, United Kingdom
| | - Bertrand Collet
- Aquaculture and Fish Health, Marine Scotland Science, Aberdeen, United Kingdom
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Aamelfot M, McBeath A, Christiansen DH, Matejusova I, Falk K. Infectious salmon anaemia virus (ISAV) mucosal infection in Atlantic salmon. Vet Res 2015; 46:120. [PMID: 26490835 PMCID: PMC4618535 DOI: 10.1186/s13567-015-0265-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 10/01/2015] [Indexed: 11/25/2022] Open
Abstract
All viruses infecting fish must cross the surface mucosal barrier to successfully enter a host. Infectious salmon anaemia virus (ISAV), the causative agent of the economically important infectious salmon anaemia (ISA) in Atlantic salmon, Salmo salar L., has been shown to use the gills as its entry point. However, other entry ports have not been investigated despite the expression of virus receptors on the surface of epithelial cells in the skin, the gastrointestinal (GI) tract and the conjunctiva. Here we investigate the ISAV mucosal infection in Atlantic salmon after experimental immersion (bath) challenge and in farmed fish collected from a confirmed outbreak of ISA in Norway. We show for the first time evidence of early replication in several mucosal surfaces in addition to the gills, including the pectoral fin, skin and GI tract suggesting several potential entry points for the virus. Initially, the infection is localized and primarily infecting epithelial cells, however at later stages it becomes systemic, infecting the endothelial cells lining the circulatory system. Viruses of low and high virulence used in the challenge revealed possible variation in virus progression during infection at the mucosal surfaces.
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Affiliation(s)
| | - Alastair McBeath
- Marine Scotland Science, Marine Laboratory, Aberdeen, Scotland, UK.
| | | | - Iveta Matejusova
- Marine Scotland Science, Marine Laboratory, Aberdeen, Scotland, UK.
| | - Knut Falk
- Norwegian Veterinary Institute, Oslo, Norway.
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Kammerer K, Falk K, Heusinger J. Zugang zu Psychotherapie im Alter: Barrieren und Möglichkeiten des Zugangs zu Psychotherapie aus Sicht von HausärztInnen. Gesundheitswesen 2015. [DOI: 10.1055/s-0035-1563051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Aamelfot M, Dale OB, McBeath A, Falk K. Host tropism of infectious salmon anaemia virus in marine and freshwater fish species. J Fish Dis 2015; 38:687-694. [PMID: 25048819 DOI: 10.1111/jfd.12284] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 05/06/2014] [Indexed: 06/03/2023]
Abstract
The aquatic orthomyxovirus infectious salmon anaemia virus (ISAV) causes a severe disease in farmed Atlantic salmon, Salmo salar L. Although some ISA outbreaks are caused by horizontal transmission of virus between farms, the source and reservoir of the virus is largely unknown and a wild host has been hypothesized. Atlantic salmon are farmed in open net-pens, allowing transmission of pathogens from wild fish and the surrounding environment to the farmed fish. In this study, a large number of fish species were investigated for ISAV host potential. For orthomyxoviruses, a specific receptor binding is the first requirement for infection; thus, the fish species were investigated for the presence of the ISAV receptor. The receptor was found to be widely distributed across the fish species. All salmonids expressed the receptor. However, only some of the cod-like and perch-like fish did, and all flat fish were negative. In the majority of the positive species, the receptor was found on endothelial cells and/or on red blood cells. The study forms a basis for further investigations and opens up the possibility for screening species to determine whether a wild host of ISAV exists.
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Affiliation(s)
- M Aamelfot
- Norwegian Veterinary Institute, Oslo, Norway
| | - O B Dale
- Norwegian Veterinary Institute, Oslo, Norway
| | - A McBeath
- Marine Scotland Science, Aberdeen, UK
| | - K Falk
- Norwegian Veterinary Institute, Oslo, Norway
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Zyriax R, Falk K. Mal ernst, mal heiter- Kinderzahngesundheit in Mecklenburg-Vorpommern. Gesundheitswesen 2015. [DOI: 10.1055/s-0035-1546853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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McBeath A, Aamelfot M, Christiansen DH, Matejusova I, Markussen T, Kaldhusdal M, Dale OB, Weli SC, Falk K. Immersion challenge with low and highly virulent infectious salmon anaemia virus reveals different pathogenesis in Atlantic salmon, Salmo salar L. J Fish Dis 2015; 38:3-15. [PMID: 24820820 DOI: 10.1111/jfd.12253] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 03/21/2014] [Accepted: 03/24/2014] [Indexed: 06/03/2023]
Abstract
The salmonid orthomyxovirus infectious salmon anaemia virus (ISAV) causes disease of varying severity in farmed Atlantic salmon, Salmo salar L. Field observations suggest that host factors, the environment and differences between ISAV strains attribute to the large variation in disease progression. Variation in host mortality and dissemination of ISAV isolates with high and low virulence (based on a previously published injection challenge) were investigated using immersion challenge. Virus dissemination was determined using real-time PCR and immunohistochemistry in several organs, including blood. Surprisingly, the low virulent virus (LVI) replicated and produced nucleoprotein at earlier time points post-infection compared to the virus of high virulence (HVI). This was particularly noticeable in the gills as indicated by different viral load profiles. However, the HVI reached a higher maximum viral load in all tested organs and full blood. This was associated with a higher mortality of 100% as compared to 20% in the LVI group by day 23 post-infection. Immersion challenge represented a more natural infection method and suggested that specific entry routes into the fish may be of key importance between ISAV strains. The results suggest that a difference in virulence is important for variations in virus dissemination and pathogenesis (disease development).
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Affiliation(s)
- A McBeath
- Marine Scotland Science, Marine Laboratory, Aberdeen, UK
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Løkka G, Austbø L, Falk K, Bromage E, Fjelldal PG, Hansen T, Hordvik I, Koppang EO. Immune parameters in the intestine of wild and reared unvaccinated and vaccinated Atlantic salmon (Salmo salar L.). Dev Comp Immunol 2014; 47:6-16. [PMID: 24968078 DOI: 10.1016/j.dci.2014.06.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 06/13/2014] [Accepted: 06/16/2014] [Indexed: 06/03/2023]
Abstract
Forming a barrier to the outside world, the gut mucosa faces the challenge of absorbing nutrients and fluids while initiating immune reactions towards potential pathogens. As a continuation to our previous publication focusing on the regional intestinal morphology in wild caught post smolt and spawning Atlantic salmon, we here investigate selected immune parameters and compare wild, reared unvaccinated and vaccinated post smolts. We observed highest transcript levels for most immune-related genes in vaccinated post smolts followed by reared unvaccinated and finally wild post smolts, indicating that farming conditions like commercial feed and vaccination might contribute to a more alerted immune system in the gut. In all groups, higher levels of immune transcripts were observed in the second segment of mid-intestine and in the posterior segment. In the life stages and conditions investigated here, we found no indication of a previously suggested population of intestinal T cells expressing MHC class II nor RAG1 expression.
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Affiliation(s)
- Guro Løkka
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway.
| | - Lars Austbø
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway.
| | - Knut Falk
- Norwegian Veterinary Institute, Oslo, Norway.
| | - Erin Bromage
- Department of Biology, University of Massachusetts Dartmouth, MA, USA.
| | | | - Tom Hansen
- Institute of Marine Research, Matre Research Station, Matredal, Norway.
| | - Ivar Hordvik
- Department of Biology, University of Bergen, Bergen, Norway.
| | - Erling Olaf Koppang
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, Oslo, Norway.
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37
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Falk K, Brown A, Murray G, Martensson M. The Reimbursement of Expensive Drugs In Hospitals in Western European Countries. Value Health 2014; 17:A428-A429. [PMID: 27201112 DOI: 10.1016/j.jval.2014.08.1081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- K Falk
- Abacus International, Manchester, UK
| | - A Brown
- Abacus International, Manchester, UK
| | - G Murray
- Abacus International, Manchester, UK
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38
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Løkka G, Falk K, Austbø L, Koppang EO. Uptake of yeast cells in the Atlantic salmon (Salmo salar L.) intestine. Dev Comp Immunol 2014; 47:77-80. [PMID: 25020196 DOI: 10.1016/j.dci.2014.07.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 07/04/2014] [Accepted: 07/06/2014] [Indexed: 06/03/2023]
Abstract
The intestinal mucosa is an important port of entry for many pathogens. Information of antigen uptake mechanisms is essential to understand and to possibly prevent infections. In teleosts, several studies have aimed at investigating particulate uptake in the gastrointestinal system that seems to vary dependent on fish species and antigen. In the present study, particulate uptake in the Atlantic salmon intestine by anal intubation of yeast cells has been investigated. In the anal intubated fish, yeast were found in the epithelium close to nuclei of macrophage-like cells and inside large mononuclear cells in the intestinal lumen, indicating uptake and possible transport of large antigen particles over the epithelium by macrophage-like cells.
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Affiliation(s)
- Guro Løkka
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, School of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway.
| | - Knut Falk
- Norwegian Veterinary Institute, Oslo, Norway.
| | - Lars Austbø
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, School of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway.
| | - Erling Olaf Koppang
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, School of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway.
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39
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Falk K, McCoy CA, Fryer CL, Greeff CW, Hungerford AL, Montgomery DS, Schmidt DW, Sheppard DG, Williams JR, Boehly TR, Benage JF. Temperature measurements of shocked silica aerogel foam. Phys Rev E Stat Nonlin Soft Matter Phys 2014; 90:033107. [PMID: 25314547 DOI: 10.1103/physreve.90.033107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Indexed: 06/04/2023]
Abstract
We present recent results of equation-of-state (EOS) measurements of shocked silica (SiO_{2}) aerogel foam at the OMEGA laser facility. Silica aerogel is an important low-density pressure standard used in many high energy density experiments, including the novel technique of shock and release. Due to its many applications, it has been a heavily studied material and has a well-known Hugoniot curve. This work then complements the velocity and pressure measurements with additional temperature data providing the full EOS information within the warm dense matter regime for the temperature interval of 1-15 eV and shock velocities between 10 and 40 km/s corresponding to shock pressures of 0.3-2 Mbar. The experimental results were compared with hydrodynamic simulations and EOS models. We found that the measured temperature was systematically lower than suggested by theoretical calculations. Simulations provide a possible explanation that the emission measured by optical pyrometry comes from a radiative precursor rather than from the shock front, which could have important implications for such measurements.
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Affiliation(s)
- K Falk
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - C A McCoy
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA
| | - C L Fryer
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - C W Greeff
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - A L Hungerford
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - D S Montgomery
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - D W Schmidt
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - D G Sheppard
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - J R Williams
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - T R Boehly
- Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623, USA
| | - J F Benage
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA and Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
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40
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Falk K. P104: Functional disability and ability 75-year-olds: A comparison of two Swedish cohorts born 30 years apart. Eur Geriatr Med 2014. [DOI: 10.1016/s1878-7649(14)70279-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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41
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Aas IB, Austbø L, König M, Syed M, Falk K, Hordvik I, Koppang EO. Transcriptional characterization of the T cell population within the salmonid interbranchial lymphoid tissue. J Immunol 2014; 193:3463-9. [PMID: 25172486 DOI: 10.4049/jimmunol.1400797] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Previously, our group has shown that the interbranchial lymphoid tissue (ILT) is a distinct structure largely consisting of T cells embedded in a meshwork of epithelial cells, with no direct resemblance to previously described lymphoid tissues. In this study, we aim to focus on the T cell population and the possibility of the ILT being a thymus analog. By characterizing structural responsiveness to Ag challenge, the presence of recombination activating genes, and different T cell-related transcripts, we attempt to further approach the immunological function of the ILT in salmonid gills. In addition to eight healthy individuals, a group of eight infectious salmon anemia virus-challenged fish were included to observe T cell responses related to infection. The results showed reduced size of ILT in the infected group, no expression of RAG-1 and -2, and a high degree of T cell diversity within the ILT. Taking into account that the ILT can be regarded as a strategically located T cell reservoir and possibly an evolutionary forerunner of mammalian MALTs right at the border to the external environment, the alteration in transcription observed may likely represent a shift in the T cell population to optimize local gill defense mechanisms.
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Affiliation(s)
- Ida Bergva Aas
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Lars Austbø
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Melanie König
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Mohasina Syed
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, 0454 Oslo, Norway
| | - Knut Falk
- Norwegian Veterinary Institute, 0454 Oslo, Norway; and
| | - Ivar Hordvik
- Department of Biology, High Technology Centre, University of Bergen, 5006 Bergen, Norway
| | - Erling O Koppang
- Department of Basic Sciences and Aquatic Medicine, Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences, 0454 Oslo, Norway
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42
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McBeath AJA, Ho YM, Aamelfot M, Hall M, Christiansen DH, Markussen T, Falk K, Matejusova I. Low virulent infectious salmon anaemia virus (ISAV) replicates and initiates the immune response earlier than a highly virulent virus in Atlantic salmon gills. Vet Res 2014; 45:83. [PMID: 25143055 PMCID: PMC4144175 DOI: 10.1186/s13567-014-0083-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 07/24/2014] [Indexed: 01/12/2023] Open
Abstract
Observations from the field and experimental evidence suggest that different strains of infectious salmon anaemia virus (ISAV) can induce disease of varying severity in Atlantic salmon. Variation in host mortality and dissemination of ISAV isolates with high and low virulence was investigated using immersion challenge; from which mortality, pathological, immunohistochemical and preliminary molecular results have been previously published. Here, real-time RT-PCR analysis and statistical modelling have been used to further investigate variation in virus load and the response of four select immune genes. Expression of type I and II interferon (IFN), Mx and γIFN induced protein (γIP) to high and low pathogenic virus infection were examined in gill, heart and anterior kidney. In addition, a novel RNA species-specific assay targeting individual RNA types was used to investigate the separate viral processes of transcription and replication. Unexpectedly, the low virulent ISAV (LVI) replicated and transcribed more rapidly in the gills compared to the highly virulent virus (HVI). Subsequently LVI was able to disseminate to the internal organs more quickly and induced a more rapid systemic immune response in the host that may have offered some protection. Contrary to this, HVI initially progressed more slowly in the gills resulting in a slower generalised infection. However HVI ultimately reached a higher viral load and induced a greater mortality.
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Affiliation(s)
| | - Yee Mai Ho
- />Marine Scotland Science, Marine Laboratory, Aberdeen, Scotland UK
| | | | - Malcolm Hall
- />Marine Scotland Science, Marine Laboratory, Aberdeen, Scotland UK
| | | | | | - Knut Falk
- />Norwegian Veterinary Institute, Oslo, Norway
| | - Iveta Matejusova
- />Marine Scotland Science, Marine Laboratory, Aberdeen, Scotland UK
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43
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Austbø L, Aas IB, König M, Weli SC, Syed M, Falk K, Koppang EO. Transcriptional response of immune genes in gills and the interbranchial lymphoid tissue of Atlantic salmon challenged with infectious salmon anaemia virus. Dev Comp Immunol 2014; 45:107-114. [PMID: 24561102 DOI: 10.1016/j.dci.2014.02.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 02/10/2014] [Accepted: 02/11/2014] [Indexed: 06/03/2023]
Abstract
Previously, it has been assumed that fish lack organized mucosa-associated lymphoid structures. Recently, an interbranchial lymphoid tissue (ILT) was described in salmonid gills at a site with substantial exposure to antigen. In this study, immune responses were examined in gills, mid-kidney and the laser-dissected ILT of Atlantic salmon (Salmo salar L.) infected with infectious salmon anaemia virus (ISAV). A strong innate response was observed in gills and mid-kidney and even in the laser-dissected ILT, despite the fact that no virus could be traced in this tissue. A small delayed increase in IgT transcripts, exclusively in the ILT, could indicate that this tissue has a role as a secondary lymphoid organ with clonal expansion of IgT expressing B-cells. Compared to the other examined tissues, gills displayed the earliest replication of the virus, further supporting this tissue as the main entry route for infection with ISAV.
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Affiliation(s)
- Lars Austbø
- Department of Basic Science and Aquatic Medicine, The Norwegian School of Veterinary Science, Ullevålsveien 72, P.O. Box 8146 Dep, 0033 Oslo, Norway
| | - Ida Bergva Aas
- Department of Basic Science and Aquatic Medicine, The Norwegian School of Veterinary Science, Ullevålsveien 72, P.O. Box 8146 Dep, 0033 Oslo, Norway
| | - Melanie König
- Department of Basic Science and Aquatic Medicine, The Norwegian School of Veterinary Science, Ullevålsveien 72, P.O. Box 8146 Dep, 0033 Oslo, Norway
| | - Simon Chioma Weli
- Norwegian Veterinary Institute, Ullevålsveien 68, P.O. Box 750 Sentrum, 0106 Oslo, Norway
| | - Mohasina Syed
- Department of Basic Science and Aquatic Medicine, The Norwegian School of Veterinary Science, Ullevålsveien 72, P.O. Box 8146 Dep, 0033 Oslo, Norway
| | - Knut Falk
- Norwegian Veterinary Institute, Ullevålsveien 68, P.O. Box 750 Sentrum, 0106 Oslo, Norway
| | - Erling Olaf Koppang
- Department of Basic Science and Aquatic Medicine, The Norwegian School of Veterinary Science, Ullevålsveien 72, P.O. Box 8146 Dep, 0033 Oslo, Norway.
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44
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Aamelfot M, Dale OB, Weli SC, Koppang EO, Falk K. The in situ distribution of glycoprotein-bound 4-O-Acetylated sialic acids in vertebrates. Glycoconj J 2014; 31:327-35. [PMID: 24833039 PMCID: PMC7088174 DOI: 10.1007/s10719-014-9529-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 05/02/2014] [Accepted: 05/04/2014] [Indexed: 11/29/2022]
Abstract
Sialic acids are located at the terminal branches of the cell glycocalyx and secreted glycan molecules. O-Acetylation is an important modification of the sialic acids, however very few studies have demonstrated the in situ distribution of the O-Acetylated sialic acids. Here the distribution of glycoprotein bound 4-O-Acetylated sialic acids (4-O-Ac sias) in vertebrates was determined using a novel virus histochemistry assay. The 4-O-Ac sias were found in the circulatory system, i.e. on the surface of endothelial cells and RBCs, of several vertebrate species, though most frequently in the cartilaginous fish (class Chondrichthyes) and the bony fish (class Osteichthyes). The O-Acetylated sialic acid was detected in 64 % of the examined fish species. Even though the sialic acid was found less commonly in higher vertebrates, it was found at the same location in the positive species. The general significance of this endothelial labelling pattern distribution is discussed. The seemingly conserved local position through the evolution of the vertebrates, suggests an evolutionary advantage of this sialic acid modification.
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Affiliation(s)
- Maria Aamelfot
- Norwegian Veterinary Institute, PO Box 750 Sentrum, 0106, Oslo, Norway
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45
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Nielsen S, Björck L, Berg J, Giang KW, Zverkova Sandström T, Falk K, Määttä S, Rosengren A. Sex-specific trends in 4-year survival in 37 276 men and women with acute myocardial infarction before the age of 55 years in Sweden, 1987-2006: a register-based cohort study. BMJ Open 2014; 4:e004598. [PMID: 24793251 PMCID: PMC4025457 DOI: 10.1136/bmjopen-2013-004598] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To examine sex-specific trends in 4-year mortality among young patients with first acute myocardial infarction (AMI), 1987-2006. DESIGN Prospective cohort study. SETTING Sweden. PARTICIPANTS We identified 37 276 cases (19.4% women; age, 25-54 years) from the Swedish Inpatient Register, 1987-2006, who had survived 28 days after an AMI. OUTCOME MEASURES 4-year mortality from all causes and standard mortality ratio (SMR). RESULTS From the first to last 5-year period, the absolute excess risk decreased from 1.38 to 0.50 and 1.53 to 0.59 per 100 person-years among men aged 25-44 and 45-54 years, respectively. Corresponding figures for women were a decrease from 2.26 to 1.17 and from 1.93 to 1.45 per 100 person-years, respectively. Trends for women were non-linear, decreasing to the same extent as those for men until the third period, then increasing. For the last 5-year period, the standardised mortality ratio for young survivors of AMI compared with the general population was 4.34 (95% CI 3.04 to 5.87) and 2.43 (95% CI 2.12 to 2.76) for men aged 25-44 and 45-54 years, respectively, and 13.53 (95% CI 8.36 to 19.93) and 6.42 (95% CI 5.24 to 7.73) for women, respectively. Deaths not associated with cardiovascular causes increased from 21.5% to 44.6% in men and 41.5% to 65.9% in women. CONCLUSIONS Young male survivors of AMI have low absolute long-term mortality rates, but these rates remain twofold to fourfold that of the general population. After favourable development until 2001, women now have higher absolute mortality than men and a 6-fold to 14-fold risk of death compared with women in the general population.
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Affiliation(s)
- S Nielsen
- Department of Molecular and Clinical Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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46
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Falk K, Gamboa EJ, Kagan G, Montgomery DS, Srinivasan B, Tzeferacos P, Benage JF. Equation of state measurements of warm dense carbon using laser-driven shock and release technique. Phys Rev Lett 2014; 112:155003. [PMID: 24785044 DOI: 10.1103/physrevlett.112.155003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Indexed: 06/03/2023]
Abstract
We present a new approach to equation of state experiments that utilizes a laser-driven shock and release technique combined with spatially resolved x-ray Thomson scattering, radiography, velocity interferometry, and optical pyrometry to obtain independent measurements of pressure, density, and temperature for carbon at warm dense matter conditions. The uniqueness of this approach relies on using a laser to create very high initial pressures to enable a very deep release when the shock moves into a low-density pressure standard. This results in material at near normal solid density and temperatures around 10 eV. The spatially resolved Thomson scattering measurements facilitate a temperature determination of the released material by isolating the scattering signal from a specific region in the target. Our results are consistent with quantum molecular dynamics calculations for carbon at these conditions and are compared to several equation of state models.
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Affiliation(s)
- K Falk
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - E J Gamboa
- University of Michigan, Ann Arbor, Michigan 48109, USA
| | - G Kagan
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - D S Montgomery
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - B Srinivasan
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - P Tzeferacos
- Flash Center for Computational Science, University of Chicago, Chicago, Illinois 60637, USA
| | - J F Benage
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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47
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Aamelfot M, Dale OB, Falk K. Infectious salmon anaemia - pathogenesis and tropism. J Fish Dis 2014; 37:291-307. [PMID: 24475971 DOI: 10.1111/jfd.12225] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 12/05/2013] [Accepted: 12/05/2013] [Indexed: 06/03/2023]
Abstract
Infectious salmon anaemia (ISA) is a serious disease of farmed Atlantic salmon caused by the aquatic orthomyxovirus infectious salmon anaemia virus (ISAV). ISA was first detected in Norway in 1984 and was characterized by severe anaemia and circulatory disturbances. This review elucidates factors related to the pathogenesis of ISA in Atlantic salmon, the dissemination of the virus in the host and the general distribution of the 4-O-acetylated sialic acids ISAV receptor. The knowledge contributes to the understanding of this disease, and why, almost 30 years after the first detection, it is still causing problems for the aquaculture industry.
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Affiliation(s)
- M Aamelfot
- Norwegian Veterinary Institute, Oslo, Norway
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48
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Fourrier M, Lester K, Thoen E, Mikalsen A, Evensen Ø, Falk K, Collet B, McBeath A. Deletions in the highly polymorphic region (HPR) of infectious salmon anaemia virus HPR0 haemagglutinin-esterase enhance viral fusion and influence the interaction with the fusion protein. J Gen Virol 2014; 95:1015-1024. [PMID: 24486627 DOI: 10.1099/vir.0.061648-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Since the discovery of a non-virulent infectious salmon anaemia virus (ISAV) HPR0 variant, many studies have speculated on the functional role of deletions within the highly polymorphic region (HPR) of genomic segment 6, which codes for the haemagglutinin-esterase (HE) protein. To address this issue, mutant HE proteins with deletions in their HPR were generated from the Scottish HPR0 template (NWM10) and fusion-inducing activity was measured using lipid (octadecyl rhodamine B) and content mixing assays (firefly luciferase). Segment six HPR was found to have a strong influence on ISAV fusion, and deletions in this near-membrane region predominantly increased the fusion-inducing ability of the resulting HE proteins. The position and length of the HPR deletions were not significant factors, suggesting that they may affect fusion non-specifically. In comparison, the amino acid composition of the associated fusion (F) protein was a more crucial criterion. Antibody co-patching and confocal fluorescence demonstrated that the HE and F proteins were highly co-localized, forming defined clusters on the cell surface post-transfection. The binding of erythrocyte ghosts on the attachment protein caused a reduction in the percentage of co-localization, suggesting that ISAV fusion might be triggered through physical separation of the F and HE proteins. In this process, HPR deletion appeared to modulate and reduce the strength of interaction between the two glycoproteins, causing more F protein to be released and activated. This work provides a first insight into the mechanism of virulence acquisition through HPR deletion, with fusion enhancement acting as a major contributing factor.
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Affiliation(s)
- Mickael Fourrier
- Marine Scotland Science, Marine Laboratory, 375 Victoria Road, Aberdeen AB11 9DB, UK
| | - Katherine Lester
- Marine Scotland Science, Marine Laboratory, 375 Victoria Road, Aberdeen AB11 9DB, UK
| | - Even Thoen
- Norwegian Veterinary Institute, Oslo, Norway
| | - Aase Mikalsen
- Norwegian School of Veterinary Science, Oslo, Norway
| | | | - Knut Falk
- Norwegian Veterinary Institute, Oslo, Norway
| | - Bertrand Collet
- Marine Scotland Science, Marine Laboratory, 375 Victoria Road, Aberdeen AB11 9DB, UK
| | - Alastair McBeath
- Marine Scotland Science, Marine Laboratory, 375 Victoria Road, Aberdeen AB11 9DB, UK
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49
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Markussen T, Sindre H, Jonassen CM, Tengs T, Kristoffersen AB, Ramsell J, Numanovic S, Hjortaas MJ, Christiansen DH, Dale OB, Falk K. Ultra-deep pyrosequencing of partial surface protein genes from infectious Salmon Anaemia virus (ISAV) suggest novel mechanisms involved in transition to virulence. PLoS One 2013; 8:e81571. [PMID: 24303056 PMCID: PMC3841194 DOI: 10.1371/journal.pone.0081571] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Accepted: 10/14/2013] [Indexed: 11/22/2022] Open
Abstract
Uncultivable HPR0 strains of infectious salmon anaemia viruses (ISAVs) infecting gills are non-virulent putative precursors of virulent ISAVs (vISAVs) causing systemic disease in farmed Atlantic salmon (Salmo salar). The transition to virulence involves two molecular events, a deletion in the highly polymorphic region (HPR) of the hemagglutinin-esterase (HE) gene and a Q266→L266 substitution or insertion next to the putative cleavage site (R267) in the fusion protein (F). We have performed ultra-deep pyrosequencing (UDPS) of these gene regions from healthy fish positive for HPR0 virus carrying full-length HPR sampled in a screening program, and a vISAV strain from an ISA outbreak at the same farming site three weeks later, and compared the mutant spectra. As the UDPS data shows the presence of both HE genotypes at both sampling times, and the outbreak strain was unlikely to be directly related to the HPR0 strain, this is the first report of a double infection with HPR0s and vISAVs. For F amplicon reads, mutation frequencies generating L266 codons in screening samples and Q266 codons in outbreak samples were not higher than at any random site. We suggest quasispecies heterogeneity as well as RNA structural properties are linked to transition to virulence. More specifically, a mechanism where selected single point mutations in the full-length HPR alter the RNA structure facilitating single- or sequential deletions in this region is proposed. The data provides stronger support for the deletion hypothesis, as opposed to recombination, as the responsible mechanism for generating the sequence deletions in HE.
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Affiliation(s)
- Turhan Markussen
- Department of Laboratory Services, Norwegian Veterinary Institute, Oslo, Norway
- * E-mail:
| | - Hilde Sindre
- Department of Laboratory Services, Norwegian Veterinary Institute, Oslo, Norway
| | | | - Torstein Tengs
- Department of Laboratory Services, Norwegian Veterinary Institute, Oslo, Norway
| | | | - Jon Ramsell
- Department of Laboratory Services, Norwegian Veterinary Institute, Oslo, Norway
| | - Sanela Numanovic
- Department of Laboratory Services, Norwegian Veterinary Institute, Oslo, Norway
| | - Monika J. Hjortaas
- Department of Laboratory Services, Norwegian Veterinary Institute, Oslo, Norway
| | - Debes H. Christiansen
- National Reference Laboratory for Fish Diseases, Food and Veterinary Authority, Torshavn, Faroe Islands
| | - Ole Bendik Dale
- Department of Laboratory Services, Norwegian Veterinary Institute, Oslo, Norway
| | - Knut Falk
- Department of Health Surveillance, Norwegian Veterinary Institute, Oslo, Norway
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50
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Fagerland HAS, Austbø L, Fritsvold C, Alarcon M, Rimstad E, Falk K, Taksdal T, Koppang EO. Pathological pigmentation in cardiac tissues of Atlantic salmon (Salmo salar L.) with cardiomyopathy syndrome. Vet Res 2013; 44:107. [PMID: 24219276 PMCID: PMC3866610 DOI: 10.1186/1297-9716-44-107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 10/09/2013] [Indexed: 12/03/2022] Open
Abstract
It is widely accepted that melanin formation may play an immunologic role in invertebrates and ectothermic vertebrates. In farmed Atlantic salmon, cardiomyopathy syndrome (CMS) is a common viral disease associated with severe cardiac inflammation that may be accompanied by heavy melanisation of the heart. By the use of histology, laser capture microdissection and transcription analysis of tyrosinase genes, we here show that this melanisation is linked to de novo melanogenesis by melanomacrophages, suggesting an active part in the inflammatory reaction. No general systemic activation of the extracutaneous pigmentary system in response to viral infections with affinity to the heart was observed.
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Affiliation(s)
| | | | | | | | | | | | | | - Erling O Koppang
- Section of Anatomy and Pathology, Department of Basic Science and Aquatic Medicine, Norwegian School of Veterinary Science, 0033 Oslo, Norway.
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