331 research outputs found
Traitement du cancer par transfert adoptif de lymphocytes T dirigés contre un antigÚne mineur d'histocompatibilité
ThÚse numérisée par la Direction des bibliothÚques de l'Université de Montréal
Pig welfare : the animal point of view, biological and behavioural approaches
Welfare refers to the subjective psychological state of an individual regarding his internal and external
environment. Since we are not yet able to read directly animal emotions and feelings, we have no other
option than to infer them from the analysis of objective signs, particularly physiological and behavioural,
based on the psychobiology of emotion, stress and adaptation. The activation of neuroendocrine
stress systems (adrenocortical axis and sympathetic nervous system) provides numerous markers to study
biological responses to environmental factors. However, their interpretation in terms of welfare must
take into account the important role of these systems in the bodyâs general physiology. Behavioural criteria
are also used (analysis of time budget and space use, abnormal behaviours, expression of social links,
preference tests), and interpreted in the context of applied ethology.Le bien-ĂȘtre fait rĂ©fĂ©rence Ă
l'Ă©tat psychologique subjectif de l'individu par rapport Ă son environnement interne et
externe. Puisque nous ne sommes pas encore capables de lire directement les sensations et
les émotions de l'animal, nous en sommes réduits à les inférer de l'analyse de leurs
manifestations objectives, en particulier physiologiques et comportementales, qui ont été
étudiées dans le contexte de la psychobiologie des émotions, du stress et de l'adaptation.
L'activation des systÚmes neuroendocriniens de réponse au stress (axe corticotrope et
systÚme nerveux sympathique) fournissent de nombreux marqueurs pour l'étude des réponses
biologiques aux facteurs d'environnement. Cependant leur interprétation en termes de
bien-ĂȘtre devra prendre en considĂ©ration le rĂŽle de ces systĂšmes dans la physiologie
générale de l'organisme. On utilisera aussi des critÚres comportementaux (analyse du
budget-temps et de l'utilisation de l'espace, comportements anormaux, expression des liens
sociaux, tests de préférences) qu'il faudra analyser dans le contexte des acquis de
l'éthologie appliquée
Nanonization of megestrol acetate by laser fragmentation in aqueous milieu
Faculté de PharmacieNanonization is a simple and effective method to improve dissolution rate and oral
bioavailability of drugs with poor water solubility. There is growing interest to downscale the nanocrystal production to enable early preclinical evaluation of new drug candidates when compound availability is scarce. The purpose of the present study was to investigate laser fragmentation to form nanosuspensions in aqueous solution of the insoluble model drug megestrol acetate (MA) using very little quantities of the drug. Laser fragmentation was obtained by focusing a femtosecond (fs) or nanosecond (ns) laser radiation on a magnetically stirred MA suspension in water or aqueous solution of a stabilizing agent. The size distribution and physicochemical properties of the drug nanoparticles were characterized, and the in vitro dissolution and in vivo oral pharmacokinetics of a laser fragmented formulation were evaluated. A MA nanosuspension was also prepared by media milling for comparison purpose. For both
laser radiations, smaller particles were obtained as the laser power was increased, but at a cost of higher degradation. Significant nanonization was achieved after a 30-min fs laser treatment at 250 mW and a 1-h ns laser treatment at 2500 mW. The degradation induced by the laser process of the drug was primarily oxidative in nature. The crystal phase of the drug was maintained, although partial loss of crystallinity was observed. The in vitro dissolution rate and in vivo bioavailability of the laser fragmented formulation were similar to those obtained with the nanosuspension prepared by media milling, and significantly improved compared to the coarse drug powder. It follows that this laser nanonization method has potential to be used for the preclinical evaluation of new drug candidates.IRSC - CRNS
Animal welfare, a driving force to change pig production systems?
Animal welfare requirements are expected to affect the future development of pig production systems
in France. Rules and regulations play a major role in this evolution. This could be in favour of larger
farms, better able to sustain their economic burden. The development of alternative production
systems should also be in favour of improved animal welfare. However, French consumer demand for
this type of production remains very low due to higher prices. On the other hand, simultaneous improvement
of animal performance and welfare provides an interesting approach, as the price increase due
to the welfare-related cost may be at least partly offset by enhanced animal performance.La prise en compte du
bien-ĂȘtre animal devrait jouer un rĂŽle important dans l'Ă©volution des systĂšmes de production
porcine en France. La réglementation y contribue de maniÚre prépondérante. Elle pourrait
favoriser le développement de structures de plus grande taille, mieux armées pour faire face
à ses conséquences économiques. Les élevages labellisés incluent dans leurs cahiers des
charges le respect du bien-ĂȘtre des animaux. De ce fait leur dĂ©veloppement contribue Ă celui
du respect du bien-ĂȘtre animal. Cependant, la demande des consommateurs pour ce type de
productions reste jusqu'à présent trÚs limitée en raison de leurs prix plus élevés.
L'amĂ©lioration conjointe du bien-ĂȘtre et des performances constitue une approche
intĂ©ressante, dans la mesure oĂč l'augmentation des coĂ»ts liĂ©s au bien-ĂȘtre peut ĂȘtre, tout
au moins en partie, compensée par l'accroissement des performances zootechniques
Les impacts des changements climatiques sur la santĂ© au QuĂ©bec : lâexemple de lâEstrie
LâOrganisation mondiale de la SantĂ© (OMS) soutient que les changements climatiques reprĂ©sentent la plus grande menace pour la santĂ© dans le monde au 21e siĂšcle. Ceux-ci influencent nĂ©gativement plusieurs dĂ©terminants sociaux et environnementaux de la santĂ© comme lâaccessibilitĂ© Ă la nourriture et la qualitĂ© de cette derniĂšre, lâeau et lâair. Blessures, impacts psychosociaux, aggravation de maladies respiratoires, malnutrition, maladies infectieuses, dĂ©cĂšs : les consĂ©quences sanitaires sont susceptibles dâaffecter les populations sur tous les continents. Le Canada se rĂ©chauffe deux fois plus rapidement que la moyenne mondiale en raison de sa proximitĂ© au pĂŽle Arctique, oĂč le rĂ©chauffement est accĂ©lĂ©rĂ© comparativement Ă lâĂ©quateur (Bush et Lemmen, 2019). Ainsi, le QuĂ©bec nâest certainement pas Ă lâabri des changements climatiques. Dans le Sud de la province, les tempĂ©ratures moyennes observĂ©es ont augmentĂ© de plus dâun degrĂ© depuis 1970 et des rĂ©percussions se font dĂ©jĂ sentir dans notre environnement. Ce rĂ©chauffement, accompagnĂ© dâune plus grande variabilitĂ© du climat (augmentation du risque dâorages, de tempĂȘtes et dâextrĂȘmes hydromĂ©tĂ©orologiques en gĂ©nĂ©ral), reprĂ©sente un dĂ©fi grandissant pour les professionnel.le.s de la santĂ©. Dans la rĂ©gion de lâEstrie, les professionnel.le.s de santĂ© publique ont effectuĂ© une analyse qui leur ont permis dâidentifier quatre principaux problĂšmes environnementaux associĂ©s aux changements climatiques, soit : les vagues de chaleur; les inondations; les tiques Ă pattes noires; le pollen de lâherbe Ă poux. Ces problĂšmes ont des impacts importants sur la santĂ©, câest-Ă -dire potentiellement graves ou qui touchent un grand nombre de personnes. Le stress et les pertes (humaines et matĂ©rielles) engendrĂ©es par ces diffĂ©rents problĂšmes environnementaux peuvent aussi reprĂ©senter une source majeure de problĂšmes psychologiques significatifs pouvant persister dans le temps. De plus, ces impacts sont variables selon les diffĂ©rents contextes sociaux des individus et des communautĂ©s, gĂ©nĂ©rant des inĂ©galitĂ©s sociales de santĂ©
Identification of a novel PPARÎČ/ÎŽ/miR-21-3p axis in UV-induced skin inflammation.
Although excessive exposure to UV is widely recognized as a major factor leading to skin perturbations and cancer, the complex mechanisms underlying inflammatory skin disorders resulting from UV exposure remain incompletely characterized. The nuclear hormone receptor PPARÎČ/ÎŽ is known to control mouse cutaneous repair and UV-induced skin cancer development. Here, we describe a novel PPARÎČ/ÎŽ-dependent molecular cascade involving TGFÎČ1 and miR-21-3p, which is activated in the epidermis in response to UV exposure. We establish that the passenger miRNA miR-21-3p, that we identify as a novel UV-induced miRNA in the epidermis, plays a pro-inflammatory function in keratinocytes and that its high level of expression in human skin is associated with psoriasis and squamous cell carcinomas. Finally, we provide evidence that inhibition of miR-21-3p reduces UV-induced cutaneous inflammation in ex vivo human skin biopsies, thereby underlining the clinical relevance of miRNA-based topical therapies for cutaneous disorders
High prevalence of PRPH2 in autosomal dominant retinitis pigmentosa in France and characterization of biochemical and clinical features.
International audiencePURPOSE:To assess the prevalence of PRPH2 in autosomal dominant retinitis pigmentosa (adRP), to report six novel mutations, to characterize the biochemical features of a recurrent novel mutation and to study the clinical features of adRP patients.DESIGN:Retrospective clinical and molecular genetic study.METHODS:Clinical investigations included visual field testing, fundus examination, high-resolution spectral-domain optical coherence tomography (OCT), fundus autofluorescence imaging and electroretinogram (ERG) recording. PRPH2 was screened by Sanger sequencing in a cohort of 310 French families with adRP. Peripherin-2 protein was produced in yeast and analyzed by Western blot.RESULTS:We identified 15 mutations, including 6 novel and 9 previously reported changes in 32 families, accounting for a prevalence of 10.3% in this adRP population. We showed that a new recurrent p.Leu254Gln mutation leads to protein aggregation, suggesting abnormal folding. The clinical severity of the disease in examined patients was moderate with 78% of the eyes having 1 to 0.5 of visual acuity and 52% of the eyes retaining more than 50% of the visual field. Some patients characteristically showed vitelliform deposits or macular involvement. In some families, pericentral RP or macular dystrophy were found in family members while widespread RP was present in other members of the same families.CONCLUSIONS:The mutations in PRPH2 account for 10.3% of adRP in the French population, which is higher than previously reported (0-8%) This makes PRPH2 the second most frequent adRP gene after RHO in our series. PRPH2 mutations cause highly variable phenotypes and moderate forms of adRP, including mild cases which could be underdiagnosed
Efficacy of the Janus kinase 1/2 inhibitor ruxolitinib in the treatment of vasculopathy associated with TMEM173-activating mutations in 3 children
International audienc
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