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Points cles Un jeune homme de 17 ans atteint d’un diabete de type 2 (DT2) connu s’est presente au service des urgences en raison de lethargie, de tachypnee et d’intense douleur abdominale apres un episode de nausees et de vomissements d’une duree de 5 jours. Son diagnostic de DT2

The sensory system of animals detects a massive and unknown array of chemical cues that evoke a diversity of physiological and behavioural responses. One group of nitrogen-containing carbon ring chemicals—nucleobases—are thought to be involved in numerous behaviours yet have received little attention. We took a top-down approach to examine responses evoked by nucleobases at behavioural, tissue, and gene expression levels. Fish generally avoided nucleobases, and this behaviour, when observed, was driven by purines but not pyrimidines. At the tissue level, olfactory neuron generator potential responses tended to be concentration specific and robust at concentrations lower than amino acid detection ranges. In terms of gene expression, more than 2000 genes were significantly upregulated following nucleobase exposure, some of which were expected (e.g., genes involved in purine binding) and some of which were not (e.g., tubulin-related genes). Humanized RNA pathway analysis showed that we had exposed the animal to a nucleobase. Our data indicate that responses to nucleobase-containing compounds may be highly structure based and are evident from changes in behaviour to mRNA expression. Many of these responses were surprising, and all provide numerous routes for further research endeavour.

Olfactory dysfunction may be caused by many factors, including physical damage and genetic abnormalities, but is also an accessible early stage symptom of several neurodegenerative diseases. Not only is the olfactory system subject to the specific histological abnormalities, but patients also lose the capacities to detect, identify, and discriminate between odors. In addition to olfactory deficits, motor dysfunction is another prominent manifestation of these conditions. Various approaches have engineered zebrafish (Danio rerio) models for neurodegenerative diseases. Despite encouraging results, there remains a great deal of potential in testing the models using established methods of olfactory and motion assessment. This chapter discusses current zebrafish models and suggests olfactory and motor endpoints for Parkinson’s, Alzheimer’s, Huntington’s disease, multiple system atrophy, and amyotrophic lateral sclerosis.

The invited papers in this special issue highlight contributions to the symposium with the same title, held at Genomes to Biomes: the First Joint Meeting of the Canadian Society for Ecology and Evolution, the Canadian Society of Zoologists, and the Society of Canadian Limnologists. Today, leading researchers cross boundaries between layers of biological organization and traditional areas of expertise, and increasingly reach beyond their historical role in society to serve as public educators and science advocates. This series includes reviews of the integrative study of animals ranging from the very small (the world’s southernmost insect) to the very large (rorqual whales), a review on using ancient DNA to elucidate the physiology of long-extinct animals, and research articles that take us from the proteomic response of honey bees to Israeli acute paralysis virus (IAPV) infection to the geographic spread of a harmful invasive earthworm in the boreal forest.