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Invited review: Mastitis Escherichia coli strains—Mastitis-associated or mammo-pathogenic?
No full textInternational audienceBovine mastitis remains a major concern for dairy farmers, mainly because of its effect on the economy of their activity and on animal welfare. Because Escherichia coli is considered a major mastitis pathogen, the diversity of E. coli strains isolated from mastitis cases has been studied for decades, with the aim to discover new ways to fight this infection. With the recent advances in whole-genome sequencing, a detailed view of the peculiarities of mastitis E. coli strains has emerged. This review aims to bring together the knowledge garnered over the years with the more recent results of whole-genome analyses. Whereas the concept of a mammary pathogenic E. coli has been proposed, because a common set of virulence genes cannot be identified among mastitis E. coli strains, we prefer the use of mastitis-associated E. coli (MAEC), with MAEC being more an "ecotype" rather than a "pathotype." Indeed, data available so far suggest that a common feature of MAEC would rather be an enrichment in fitness capabilities that makes them well-suited for survival and rapid adaptation to changing biotopes in the mammary gland, which we qualify as intramammary ecotopes
Brucella vulpis sp. nov. is attenuated in a BALB/c murine model of infection: Of mice and foxes
No full textInternational audienceBrucellosis, caused by Brucella spp., is a zoonotic disease of global significance, affecting a wide range of animal hosts. Since the discovery of Brucella spp. in wildlife, novel bacteria belonging to the genus Brucella have been isolated across various terrestrial and aquatic animals. Among them are Brucella vulpis isolates F60T and F965 cultured from two red foxes (Vulpes vulpes) tissues, classified within the Brucella genus in 2016; however, the behavior and pathogenic potential of B. vulpis in a mouse model have not been investigated yet. In this study, the virulence and serologic response of B. vulpis F60T and F965 in BALB/c mice were investigated and compared using B. suis 1330, B. microti CCM 4915 and Brucella sp. 83-210 representative of phylogenetically more distant or non-core species, and previously shown to be also virulent in the mouse model. Our findings indicate that B. vulpis exhibits an attenuated infection pattern at 104 CFU, with lower levels of persistence in the spleen and liver than B. suis 1330, B. microti CCM 4915, and Brucella sp. 83-210, and no associated mortality in mice. B. vulpis F60T and F965 elicited a similar serologic response compared to B. suis 1330, B. microti CCM 4915, and Brucella sp. 83-210, based on an indirect enzyme-linked immunosorbent assay (iELISA). These results indicate that, in a mouse infection model, B. vulpis can replicate and is attenuated, at least for the isolates investigated, compared to the other virulent Brucella spp. studied
Neospora caninum as delivery vehicle for anti-PD-L1 scFv-Fc: A novel approach for cancer immunotherapy
No full textInternational audienceNeospora caninum, a potential anticancer agent able to reactivate the immune response within the tumor microenvironment (TME), has recently shown enhanced immunomodulatory properties in different tumor models when armed with the cytokine, Il-15. In the current area of combination immunotherapy strategies designed to overcome treatment resistance, we engineered for the first time the protozoan Neospora caninum to vectorize and secrete a single-chain variable fragment fused to fragment crystallizable region (scFv-Fc) targeting human programmed cell death ligand 1 (PD-L1). Following validation of its secretion through the micronemes (protozoa secretory organelles), we demonstrated that the scFv-Fc could bind PD-L1 on mouse and human tumor cells, block the programmed cell death protein 1 (PD-1)/PD-L1 pathway leading to potentiate the T cell lymphocyte activity. Additionally, the scFv-Fc induced antibody-dependent cellular phagocytosis (ADCP) and antibody-dependent cellular cytotoxicity (ADCC). Those data demonstrate the feasibility of vectoring and secreting a functional antibody fragment by N. caninum, opening promising avenues for future research
Biphonation in animal vocalizations: insights into communicative functions and production mechanisms
No full textInternational audienceBiphonation, defined as the simultaneous production of two distinct, non-harmonically related fundamental frequencies, has traditionally been viewed as an anomaly or a by-product of vocal pathology. Recent studies have challenged this assumption and found that biphonic calls are present in the natural vocalizations of a wide range of taxa, including birds, amphibians and mammals. This phenomenon could play an essential role in communicating distinct pieces of information at short- versus long-distance, increase call complexity to allow more individually distinct calls, and provide cues to the sender’s direction of movement. Proposed mechanisms underlying biphonation production include asymmetries in vocal fold oscillations, the addition of aerodynamic whistles, the involvement of secondary structures, and bilateral specializations. This scoping review underscores the adaptive significance of biphonic calls in non-human animals, highlighting their role in the evolution of vocal communication and suggesting avenues for future research. This article is part of the theme issue ‘Nonlinear phenomena in vertebrate vocalizations: mechanisms and communicative functions’
Acoustic context and dynamics of nonlinear phenomena in mammalian calls: the case of puppy whines
No full textInternational audienceNonlinear phenomena (NLP) are often associated with high arousal and function to grab attention and/or signal urgency in vocalizations such as distress calls. Although biomechanical models and in vivo / ex vivo experiments suggest that their occurrence reflects the destabilization of vocal fold vibration under intense subglottal pressure and muscle tension, comprehensive descriptions of the dynamics of NLP occurrence in natural vocal signals are critically lacking. Here, to plug this gap, we report the timing, type, extent and acoustic context of NLP in 12 011 whines produced by Beagle puppies ( Canis familiaris ) during a brief separation from their mothers. Within bouts of whines, we show that both the proportion of time vocalizing and the number of whines containing NLP, especially those with chaos, increase with time since separation, presumably reflecting heightened arousal. Within whines, we show that NLP are typically produced during the first half of the call, following the steepest rises in pitch (fundamental frequency, f o ) and amplitude. While our study reinforces the notion that NLP arise in calls due to instabilities in vocal production during high arousal, it also provides novel and efficient analytical tools for quantifying nonlinear acoustics in ecologically relevant mammal vocal communication contexts. This article is part of the theme issue ‘Nonlinear phenomena in vertebrate vocalizations: mechanisms and communicative functions’
Introduction aux musiques de séries télévisées: De Badge 714 à Lost
No full textInternational audienceMalgré tout l’intérêt qu’elles suscitent aujourd’hui auprès des téléspectateurs, les musiques originales de séries télévisées étasuniennes ont longtemps souffert d’être reléguées à l’arrière-plan du vaste univers des musiques à l’image. Pourtant, ces partitions regorgent de mystères, de trouvailles sonores et de ritournelles entêtantes qui ne demandent qu’à être déchiffrées. Quelles sont les spécificités des musiques télésériales ? Comment interagissent-elles avec l’image, la narration ou la répétition propre à l’expérience sérielle proposée par la télévision ? Quels liens entretiennent-elles vraiment avec les musiques du cinéma hollywoodien souvent décrites comme un modèle incontournable ? L’ouvrage propose ainsi d’éclairer l’origine des musiques télésériales américaines à partir des années 1950, puis d’en suivre les mutations stylistiques pour, enfin, mettre au jour plusieurs principes musicaux propres aux séries des grands networks. Badge 714 (Walter Schumann), Buffy contre les vampires (Christopher Beck), X-Files (Mark Snow) ou encore Lost : Les Disparus (Michael Giacchino) font notamment l’objet d’analyses musicologiques qui permettent d’éclairer les singularités d’un territoire en partie inexploré
Development of a Short Version of the Dissociation Questionnaire (sDIS-Q) : Assessment of Its Psychometric Properties within a Non-Clinical and Clinical Sample
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Towards more efficient, more specific, and safer MRI contrast agents: a Portuguese–French collaborative journey
No full textInternational audienceAlthough complexes of the paramagnetic Gd(III) ion have been used with great success for the past 40 years to enhance image contrast in magnetic resonance imaging (MRI), important challenges such as improving the relaxation efficacy, the specificity, the safety, and the environmental impact of these agents remain in this field. Thanks to a collaborative effort between the Centre of Molecular Biophysics in Orléans, France and the Coimbra Chemistry Centre - Institute of Molecular Sciences in Coimbra, Portugal, there have been important advances in the chemistry of MRI probes. The authors have developed rigid, medium-sized, and bishydrated Gd(III) complexes specifically optimized for high-field applications with successful validation in vivo. For the specific targeting of amyloid peptides implicated in many pathologies such as Alzheimer’s disease and diabetes, they have designed benzothiazole-derivative metal chelates with detection potential in MRI, optical, and nuclear imaging modalities. The authors have gained valuable insights into the aggregation behavior of these complexes in solution and how this affects peptide binding affinity. More recently, manganese porphyrin complexes have been investigated with the objective of visualizing the tissue redox state based on the Mn(II)/Mn(III) redox switch, which can be followed not only in classical H detection but also in F MRI