Protection against myxomatosis and rabbit viral hemorrhagic disease with recombinant myxoma viruses expressing rabbit hemorrhagic disease virus capsid protein

Two myxoma virus-rabbit hemorrhagic disease virus (RHDV) recombinant viruses were constructed with the SG33 strain of myxoma virus to protect rabbits against myxomatosis and rabbit viral hemorrhagic disease. These recombinant viruses expressed the RHDV capsid protein (VP60). The recombinant protein, which is 60 kDa in size, was antigenic, as revealed by its reaction in immunoprecipitation with antibodies raised against RHDV. Both recombinant viruses induced high levels of RHDV- and myxoma virus-specific antibodies in rabbits after immunization. Inoculations by the intradermal route protected animals against virulent RHDV and myxoma virus challenges

Unusual use of objects after unilateral brain damage. The technical reasoning model.

International audienceIt has been suggested that gesture engrams, conceptual knowledge and/or the ability to infer function from structure can support object use. The present paper proposes an alternative view which is based upon the idea that object use requires solely the ability to reason about technical means provided by objects. Technical means are abstract principles which are not linked with any object representation (e.g., cutting involves the opposition between dense and permeable material). The technical reasoning model predicts that the inability to perform technical reasoning should impair performance in any situation requiring the use of objects (in a conventional way or not). Twenty left brain-damaged (LBD) patients, 11 right brain-damaged (RBD) patients and 41 healthy controls were examined on experimental tests assessing the conventional use of objects (e.g., screwing a screw with a screwdriver), conceptual knowledge about object function, pantomime of object use and recognition of object utilization gestures. We also designed the Unusual Use of Objects test, which demands unusual applications of objects to achieve a purpose for which the usually applied object is not provided (e.g., screwing a screw with a knife). The key findings are that only LBD patients have more difficulties on the Unusual Use of Objects Test than controls or RBD patients, and that the severity of their impairment is correlated with that on conventional use of objects. Correlations with tests assessing conceptual knowledge as well as with tests of pantomime of object use and recognition of object utilization gestures were weaker. These results support the technical reasoning model and question the role of conceptual knowledge and gesture engrams in object use. Since the technical reasoning model also predicts two distinct technical disorders, the discussion focuses on the existence of these disorders in regard to individual performance profiles obtained in the Unusual Use of Objects test

Retrospective studies on rabbit haemorrhagic disease outbreaks caused by RHDV GI.2 virus on farms in France from 2013 to 2018

[EN] Rabbit haemorrhagic disease (RHD) is a critical health threat to the rabbit industry in Europe. In 2018, the French rabbit industry adopted a voluntary control plan against this disease. In this context, two epidemiological studies were conducted on RHD outbreaks that occurred between 2013 and 2018 in France. The objectives were to describe the spread of RHD due to the new genotype RHDV GI.2 (rabbit haemorrhagic disease virus GI.2) and to identify rearing factors influencing the occurrence of the disease in order to guide the prevention measures recommended in the control plan. An analysis of cases on 295 farms between 2013 and 2017 showed that 32% of farms were affected at least once; the incidence of the disease increased in 2016-2017 compared to 2013-2015. Farms already affected in 2013-2015 had a higher risk of being infected in 2016-2017 than those that remained unaffected until 2015 (Relative Risk and 95% Confident Interval 1.7 [1.1-2.7]). A case-control study carried out between 2016 and 2018 on 37 outbreaks and 32 control farms revealed variability in biosecurity and decontamination practices between farms. The risk of being infected tends to be linked to these practices, but certain structural factors (e.g. the manure disposal system, transfer of rabbits at weaning) could also influence the risk of virus introduction into farms. In the context of a limited vaccination coverage of the farms (only females are vaccinated), these hypotheses will be studied further, using information from the RHD outbreak monitoring system implemented at the same time as the control plan in 2018.This study was founded by the French Ministry of Agriculture (2017-430 / 170274).Huneau-Salaün, A.; Boucher, S.; Fontaine, J.; Le Normand, B.; Lopez, S.; Maurice, T.; Nouvel, L.... (2021). Retrospective studies on rabbit haemorrhagic disease outbreaks caused by RHDV GI.2 virus on farms in France from 2013 to 2018. World Rabbit Science. 29(2):87-98. https://doi.org/10.4995/wrs.2021.12800OJS8798292Abrantes J., Van der Loo W., Le Pendu J., Esteves P.J. 2012. Rabbit haemorrhagic disease (RHD) and rabbit haemorrhagic disease virus (RHDV): a review. Vet. Res., 43: 12.https://doi.org/10.1186/1297-9716-43-12Capucci L., Cavadini P., Schiavitto M., Lombardi G., Lavazza A. 2017. Increased pathogenicity in rabbit haemorrhagic disease virus type 2 (RHDV2). Vet. Record., 180: 426. https://doi.org/10.1136/vr.104132Carvalho C.L., Leclerc Duarte E., Monteiro J.M., Afonso C., Pacheco J., Carvalho P., Mendonça P., Botelho A., Albuquerque T., Themudo P., Fevereiro M., Henriques A.M., Santos Barros S., Dias Duarte M. 2017. Progression of rabbit haemorrhagic disease virus 2 upon vaccination in anindustrial rabbitry: a laboratorial approach. World Rabbit Sci., 25: 73-85. https://doi.org/10.4995/wrs.2017.5708Cooke B.D., Fenner F. 2002. Rabbit haemorrhagic disease and the biological control of wild rabbits, Oryctolagus Cuniculus, in Australia and New Zealand. Wildlife Res., 29: 689-706. https://doi.org/10.1071/WR02010Dalton K.P., Balseiro A., Juste R.A., Podadera A., Nicieza I., del Llano D., González R., Martin Alonso J.M., Prieto J.M., Parra F., Casais R. 2018. Clinical course and pathogenicity of variant rabbit haemorrhagic disease virus in experimentally infected adult and kit rabbits: Significance towards control and spread. Vet. Microbiol., 220: 24-32. https://doi.org/10.1016/j.vetmic.2018.04.033Dohoo I., Martin W., Stryhn H. 2003. Measures of disease frequency. In: Veterinary Epidemiologic Research, First Edition, AVC Inc., Charlottetown, Canada, 65-84.Hall R.N., Huang N., Roberts J., Strive T. 2019. Carrion flies as sentinels for monitoring lagovirus activity in Australia. Transboundary Emerg. Dis., 66: 2025-2032. https://doi.org/10.1111/tbed.13250Henning J., Meers J., Davies R., Morris R.S. 2005. Survival of rabbit haemorrhagic disease virus (RHDV) in the environment. Epidemiol. Infect., 133: 719-730. https://doi.org/10.1017/S0950268805003766Hurand J. 2016. L'élevage de lapins de chair en France, résultats technico-économiques 2015. Tema, 40.ITAVI. 2019. Situation de la filière cunicole. Novembre 2019. 6 p. Available athttps://www.itavi.asso.fr/content/note-deconjoncture-lapins-7Accessed December 2019.Le Gall-Reculé G., Zwingelstein F., Boucher S., Le Normand B., Plassiart G., Portejoie Y., Decors A., Bertagnoli S., Guérin J.L., Marchandeau S. 2011. Detection of a new variant of rabbit haemorrhagic disease virus in France. Vet. Rec., 168: 137- 138. https://doi.org/10.1136/vr.d697Le Gall-Reculé G., Lavazza A., Marchandeau S., Bertagnoli S., Zwingelstein F., Cavadini P., Martinelli N., Lombardi G., Guérin J.L., Lemaitre E., Decors A., Boucher S., Le Normand B., Capucci L. 2013. Emergence of a new lagovirus related to Rabbit haemorrhagic disease virus. Vet. Res., 44:81. https://doi.org/10.1186/1297-9716-44-81Le Gall-Reculé G., Boucher S. 2017. Connaissances et actualités sur la maladie hémorragique du lapin. In Proc.: 17èmes Journées de la Recherche Cunicole, 21-22 November, 2017. Le Mans, France. 97-109.Le Minor O., Joudou L., Le Moullec T., Beilvert F. 2017. Innocuité et efficacité de la vaccination à 2 et 3 semaines d'âge contre le virus RHDV2 de la maladie hémorragique virale du lapin (VHD). In Proc.:17èmes Journées de la Recherche Cunicole, 21-22 November, 2017. Le Mans, France. 127-130.Le Minor O., Boucher S., Joudou L., Mellet R., Sourice M., Le Moullec T., Nicoler A., Beilvert F., Sigognault-Flochlay A. 2019. Rabbit haemorrhagic disease: experimental study of a recent highly pathogenic GI.2/RJDV2/b strain and evaluation of vaccine efficacy. World Rabbit Sci., 27: 143-156.https://doi.org/10.4995/wrs.2019.11082Le Pendu J., Abrantes J., Bertagnoli S., Guitton J.S., Le Gall-Reculé G., Lopes A.M., Marchandeau S., Alda F., Almeida T., Célio A. C., Barcena J., Burmakina G., Blanco E., Calvete C., Cavadini P., Cooke B., Dalton K., Mateos M.D., Deptula W., Eden J.S., Wang F., Ferreira C.C., Ferreira P., Foronda P., Gonçalves D., Gavier-Widén D., Hall R., Hukowska-Szematowicz B., Kerr P., Kovaliski J., Lavazza A., Mahar J., Malogolovkin A., Marques R.M., Marques S., Martin-Alonso A., Monterroso P., MorenoS., Mutze G., Naimanis A., Niedzwiedzka-Rystwej P., Peacock D., Parra F., Rocchi M., Rouco C., Ruvoën-Clouet N., Silva E., Silvério D., Strive T., Thompson G., Tokarz-Deptula B., Esteves P. 2017. Proposal for a unified classification system and nomenclature of lagoviruses. J. Gen. Virol., 98: 1658-1666. https://doi.org/10.1099/jgv.0.000840Matthaei M., Kerr P.J., Read A.J., Hick P., Haboury S., Wright J.D., Strive T. 2014. Comparative quantitative monitoring of rabbit haemorrhagic disease viruses in rabbit kittens. Virol. J., 11: 109. https://doi.org/10.1186/1743-422X-11-109Mc Coll K.A., Merchant J.C., Hardy J., Cooke B.D., Robinson A., Westbury H.A. 2002. Evidence for insect transmission of rabbit haemorrhagic disease virus. Epidemiol. Infect., 129: 655-663. https://doi.org/10.1017/S0950268802007756Neimanis A.S., Larsson Pettersson U., Huang N., Gavier-Widen D., Strive T. 2018. Elucidation of the pathology and tissue distribution of Lagovirus europaeus GI.2/RHDV2 (rabbit haemorrhagic disease virus 2) in young and adult rabbits (Oryctolagus cuniculus). Vet. Res., 49:46. https://doi.org/10.1186/s13567-018-0540-zRosell J.M., de la Fuente L.F., Parra F., Dalton K.P., Badiola Sáiz J.I., Pérez de Rozas A., Badiola Díez J.J., Fernández de Luco D., Casal J., Majó N., Casas J., Garriga R., Fernández Magariños X.M. 2019. Myxomatosis and Rabbit Haemorrhagic Disease: A 30-Year Study of the Occurrence on Commercial Farms in Spain. Animals, 9: 780. https://doi.org/10.3390/ani9100780Rouco C., Aguayo-Adán J.A., Santoro S., Abrantes J., Delibes-Mateos M. 2019. Worldwide rapid spread of the novel rabbit haemorrhagic disease virus (GI.2/RHDV2/b). Transboundary Emerg. Dis., 66: 1762-1764.https://doi.org/10.1111/tbed.1318

Characterisation of a non-pathogenic and non-protective infectious rabbit lagovirus related to RHDV

The existence of non-pathogenic RHDV strains was established when a non-lethal virus named rabbit calicivirus (RCV) was characterised in 1996 in Italy. Since then, different RNA sequences related to RHDV have been detected in apparently healthy domestic and wild rabbits, and recently a new lagovirus was identified in Australia. We have characterised from seropositive healthy domestic rabbits a non-lethal lagovirus that differs from RHDV in terms of pathogenicity, tissue tropism and capsid protein sequence. Phylogenetic analyses have revealed that it is close to the Ashington strain and to the RCV, but distinct. We proved experimentally that it is infectious but non-pathogenic and demonstrated that, contrary to the other described non-pathogenic lagoviruses, it induces antibodies that do not protect against RHDV. Our results indicate the existence of a gradient of cross-protection between circulating strains, from non-protective, partially protective to protective strains, and highlight the extent of diversity within the genus Lagovirus

Histo-Blood Group Antigens Act as Attachment Factors of Rabbit Hemorrhagic Disease Virus Infection in a Virus Strain-Dependent Manner

Rabbit Hemorrhagic disease virus (RHDV), a calicivirus of the Lagovirus genus, and responsible for rabbit hemorrhagic disease (RHD), kills rabbits between 48 to 72 hours post infection with mortality rates as high as 50–90%. Caliciviruses, including noroviruses and RHDV, have been shown to bind histo-blood group antigens (HBGA) and human non-secretor individuals lacking ABH antigens in epithelia have been found to be resistant to norovirus infection. RHDV virus-like particles have previously been shown to bind the H type 2 and A antigens. In this study we present a comprehensive assessment of the strain-specific binding patterns of different RHDV isolates to HBGAs. We characterized the HBGA expression in the duodenum of wild and domestic rabbits by mass spectrometry and relative quantification of A, B and H type 2 expression. A detailed binding analysis of a range of RHDV strains, to synthetic sugars and human red blood cells, as well as to rabbit duodenum, a likely gastrointestinal site for viral entrance was performed. Enzymatic cleavage of HBGA epitopes confirmed binding specificity. Binding was observed to blood group B, A and H type 2 epitopes in a strain-dependent manner with slight differences in specificity for A, B or H epitopes allowing RHDV strains to preferentially recognize different subgroups of animals. Strains related to the earliest described RHDV outbreak were not able to bind A, whereas all other genotypes have acquired A binding. In an experimental infection study, rabbits lacking the correct HBGA ligands were resistant to lethal RHDV infection at low challenge doses. Similarly, survivors of outbreaks in wild populations showed increased frequency of weak binding phenotypes, indicating selection for host resistance depending on the strain circulating in the population. HBGAs thus act as attachment factors facilitating infection, while their polymorphism of expression could contribute to generate genetic resistance to RHDV at the population level

Contribution to the study of Rickettsiosis of the Saint-Jacques Scallop Pecten maximus (Mollusca : Bivalvia)

A la suite de mortalités dans la population de coquilles St- Jacques, Pecten marimus, de la baie de St-Brieuc, un procaryote intracellulaire a été mis en évidence dans les branchies et apparenté à l'ordre des Ricketts iales sur la base de critères ultrastructuraux. Un protocole de purification, reposant sur des centrifugations différentielles et isopycniques, a été élaboré. Les protéines constitutives majeures et plusieurs activités enzymatiques ont été caractérisées. Des anticorps polyclonaux et monoclonaux ont été préparés et appliqués à des immunodiagnos tics de la rickettsie. Des fragments de restriction de l'ADN du procaryote ont été clonés et analysés en tant que sondes . Plusieurs fragments ont été séquencés et des oligonucléotides spécifiques ont été synthétisés et utilisés comme amorces selon la technique de PCR. L'application de plu sieurs de ces méthodes et réactifs de caractérisation a été validée pour d'autres rickettsies de pectinidés. L'épidémiologie de la rickettsiose a été étudiée d'un point de vue spatio- temporel. A l'échelle européenne, les taux et les degrés d'infection se sont avérés très différents . En baie de St-Brieuc, la disparition des animaux les plus infectés est apparue concommitante avec les mortalités à la fin de l'hiver. La transmission horizontale du procalyote a été établie dans le milieu et au laboratoire. L'impact de la rickettsiose sur la physiologie de l'hôte se traduit par un bilan énergétique négatif chez des animaux fortement infectés maintenus à basse température. Il a été démontré que les hémocytes de P. maximus sont capables de produire des radicaux toxiques de l'oxygène lors de la phagocytose de particules, mais la rickettsie interfère avec le processus microbicide. Ces résultats sont en faveur chez P. maximus de l'hypothèse d'un rôle pathogène de la rickettsiose.Populations of St-Jacques scallops, Pecten maximus, from St - Brieuc Bay, suffered mass mortalities between 1985 and 1988. An intracellular prokaryote was found in the gills of these scallops, which was identified as a Rickettsiales - like organism (RLO), on the basis of its ultrastructure. A protocol for purification of the RLO was developed, which relied on differential and isopycnic centrifugations. The major constitutive proteins and several enzyme activities were characterized. Polyclonal and monoclonal antibodies were prepared and used in immunodiagnosis of the RLO. Also, restriction fragments of DNA were cloned and analysed for use as probes. Several fragments were sequenced and specific oligonucleotides were synthesized and then used as primers for PCR. Several of the above methods and reactifs were applied to RLO found in other pectinids. Epidemiology of the RLO was studied from a spatial-temporal point of view. The rate and degree of infection were very different throughout Europe. In St-Brieuc Bay, the disappearance of the most heavily infected scallops occurred at the end of winter. Horizontal transmission was established in the field and in the laboratory. Rickettsiosis has a negative effect on the energy budget of heavily infected scallops heId at low temperature. It was shown th at the hemocytes of P. maximus produce toxic radicals during phagocytosis, but this phenomenon was not triggered by RLO. These results support the hypothesis that the RLO are pathogenic for P. maximu

Persistence of infectious pancreatic necrosis virus (IPNV) in scallops Pecten maximus

Infectious pancreatic necrosis virus (IPNV), serotype N1 isolated from scallops Pecten maximus in Norway, was propagated and used in both inoculation and bath challenge experiments with scallops in vivo. Although virus titers measured in scallop tissues decreased, depuration of virus was not complete during the experimental periods. IPNV was still detectable 11 mo after injection. The highest virus titer was found in the hepatopancreas, but virus was also detectable in other tissues, as well as in the hemolymph. After a bath challenge, uptake of IPNV was shown. Virus was present in hepatopancreas, gonad, kidney, mantle, gill, rectum and in the hemolymph 1 d after the uptake. The titer was highest in the hepatopancreas where virus was detectable at the end of the experiment, 50 d after challenge. Virus levels in the rectum decreased below detectable levels after Day 30. Titers decreased rapidly in the hemolymph where no virus could be detected after Day 8. Challenges did not result in increased mortality or in clear pathological changes in the scallops. No evidence of viral replication within the scallops was found

Les infections à influenzavirus de sous-types H5 chez des canards domestiques (étude des possibilités de prévention par la vaccination avec des pseudoparticules virales)

Les influenzavirus aviaires faiblement pathogènes (LPAI) de sous-types H5 et H7 peuvent après mutation devenir hautement pathogènes (HP) et avoir de graves conséquences en santé publique et animale. Les canards ont un rôle essentiel dans la transmission des LPAI, il est donc primordial de contrôler et d empêcher la circulation des LPAI chez cette espèce. Parmi les vaccins recombinants ou inactivés évalués chez le canard, aucune donnée n existe concernant la protection offerte vis-à-vis des LPAI H5. Nous avons généré un baculovirus triple recombinant permettant l expression des protéines HA, NA et M. La protection offerte par un lysat de cellules exprimant les 3 protéines recombinantes a été évaluée chez des canards de Barbarie après infection par le LPAI H5N3 homologue. Une diminution significative de l excrétion virale cloacale et un retard du pic d excrétion virale trachéale ont été observés. Pour optimiser la formation de VLPs, le plasmide triple recombinant a été modifié. Les VLPs présentent à leur surface des protéines HA et NA biologiquement actives et antigéniques. Un baculovirus quadruple recombinant a été généré en ajoutant le gène M2 et la formation de VLPs a été confirmée. Le pouvoir vaccinant des deux types de VLPs devra être évalué.H5 and H7 low pathogenic avian influenza (LPAI) viruses can mutate into highly pathogenic (HP) and lead to serious problems in both animal and public health. Domestic ducks playing a pivotal role in the transmission cycle of H5 LPAI viruses, it s essential to control and prevent the circulation and spread of these viruses in this species. A few inactivated and recombinant vaccines have been assessed in ducks, mainly for preventing HP H5N1 influenzavirus. Nevertheless, H5 LPAI virus duck vaccination is poorly documented. We generated a triple recombinant baculovirus allowing the expression of HA, NA and M proteins. The protection afforded by cell lysate expressing three recombinant proteins was assessed in Muscovy ducks against H5N3 LP virus challenge. A significant decrease of cloacal shedding and a delayed peak of tracheal shedding were observed. To improve the VLPs formation, triple recombinant plasmid was modified. HA and NA were present on the VLPs surface and were biologically active and antigenic. A quadruple recombinant baculovirus was generated by adding the M2 gene, and VLPs formation was confirmed. The protection afforded by the two types of VLPs will have to be evaluated.RENNES1-BU Sciences Philo (352382102) / SudocSudocFranceF

Evaluation des traumatismes crâniens en vie quotidienne : Intérêt de la réalité virtuelle

IntroductionLes séquelles neuropsychologiques consécutives à un traumatisme crânio-encéphalique peuvent être multiples, affectant la cognition (surtout dans ses dimensions attention, mémoire, fonctions exécutives et conscience des troubles, l’humeur (anxiété, dépression) et le comportement (réduction des activités, désinhibition). Plus récemment, des troubles de la cognition sociale ont été décrits sous forme de déficits de perception des émotions, de théorie de l’esprit ou d’empathie. Ces derniers troubles seront évoqués ailleurs dans cet ouvrage.Ces séquelles entraînent aussi des difficultés, parfois persistantes, dans la réalisation des activités de la vie quotidienne. Nous entendons ici par activités de la vie quotidienne toutes les tâches familières sollicitant des processus cognitifs tels que l’ordonnancement séquentiel des actions, la sélection des objets ou des outils pour atteindre des buts pratiques, comme par exemple “Préparer un tasse de café au lait”.Chacun d’entre nous réalise ce type d’activité de façon journalière, avec une impression de grande facilité. Les patients neurologiques, dont ceux avec un traumatisme crânien, commettent souvent des erreurs dans la conduite de ces activités, erreurs qui peuvent compromettre l’atteinte du but (Luria, 1975; Schwartz et al., 1991, 1998). Ce chapitre se propose de faire un point sur la sémiologie des perturbations des activités de la vie quotidienne après un traumatisme crânien grave et sur les différents types d’outils permettant de les appréhender.</p