Entre petite criminalité et grande misère : la prison des hommes à Montréal et sa population (1836-1912)

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

Modification of Salmonella Typhimurium Motility by the Probiotic Yeast Strain Saccharomyces boulardii

BACKGROUND: Motility is an important component of Salmonella enterica serovar Typhimurium (ST) pathogenesis allowing the bacteria to move into appropriate niches, across the mucus layer and invade the intestinal epithelium. In vitro, flagellum-associated motility is closely related to the invasive properties of ST. The probiotic yeast Saccharomyces boulardii BIOCODEX (S.b-B) is widely prescribed for the prophylaxis and treatment of diarrheal diseases caused by bacteria or antibiotics. In case of Salmonella infection, S.b-B has been shown to decrease ST invasion of T84 colon cell line. The present study was designed to investigate the impact of S.b-B on ST motility. METHODOLOGY/PRINCIPAL FINDINGS: Experiments were performed on human colonic T84 cells infected by the Salmonella strain 1344 alone or in the presence of S.b-B. The motility of Salmonella was recorded by time-lapse video microscopy. Next, a manual tracking was performed to analyze bacteria dynamics (MTrackJ plugin, NIH image J software). This revealed that the speed of bacterial movement was modified in the presence of S.b-B. The median curvilinear velocity (CLV) of Salmonella incubated alone with T84 decreased from 43.3 µm/sec to 31.2 µm/sec in the presence of S.b-B. Measurement of track linearity (TL) showed similar trends: S.b-B decreased by 15% the number of bacteria with linear tract (LT) and increased by 22% the number of bacteria with rotator tract (RT). Correlation between ST motility and invasion was further established by studying a non-motile flagella-deficient ST strain. Indeed this strain that moved with a CLV of 0.5 µm/sec, presented a majority of RT and a significant decrease in invasion properties. Importantly, we show that S.b-B modified the motility of the pathogenic strain SL1344 and significantly decreased invasion of T84 cells by this strain. CONCLUSIONS: This study reveals that S.b-B modifies Salmonella's motility and trajectory which may account for the modification of Salmonella's invasion

Bioturbation in a Declining Oxygen Environment, in situ Observations from Wormcam

Bioturbation, the displacement and mixing of sediment particles by fauna or flora, facilitates life supporting processes by increasing the quality of marine sediments. In the marine environment bioturbation is primarily mediated by infaunal organisms, which are susceptible to perturbations in their surrounding environment due to their sedentary life history traits. Of particular concern is hypoxia, dissolved oxygen (DO) concentrations ≤2.8 mg l−1, a prevalent and persistent problem that affects both pelagic and benthic fauna. A benthic observing system (Wormcam) consisting of a buoy, telemetering electronics, sediment profile camera, and water quality datasonde was developed and deployed in the Rappahannock River, VA, USA, in an area known to experience seasonal hypoxia from early spring to late fall. Wormcam transmitted a time series of in situ images and water quality data, to a website via wireless internet modem, for 5 months spanning normoxic and hypoxic periods. Hypoxia was found to significantly reduce bioturbation through reductions in burrow lengths, burrow production, and burrowing depth. Although infaunal activity was greatly reduced during hypoxic and near anoxic conditions, some individuals remained active. Low concentrations of DO in the water column limited bioturbation by infaunal burrowers and likely reduced redox cycling between aerobic and anaerobic states. This study emphasizes the importance of in situ observations for understanding how components of an ecosystem respond to hypoxia

Impact of oil on bacterial community structure in bioturbated sediments

Oil spills threaten coastlines where biological processes supply essential ecosystem services. Therefore, it is crucial to understand how oil influences the microbial communities in sediments that play key roles in ecosystem functioning. Ecosystems such as sediments are characterized by intensive bioturbation due to burrowing macrofauna that may modify the microbial metabolisms. It is thus essential to consider the bioturbation when determining the impact of oil on microbial communities. In this study, an experimental laboratory device maintaining pristine collected mudflat sediments in microcosms closer to true environmental conditions - with tidal cycles and natural seawater - was used to simulate an oil spill under bioturbation conditions. Different conditions were applied to the microcosms including an addition of: standardized oil (Blend Arabian Light crude oil, 25.6 mg.g21 wet sediment), the common burrowing organism Hediste (Nereis) diversicolor and both the oil and H. diversicolor. The addition of H. diversicolor and its associated bioturbation did not affect the removal of petroleum hydrocarbons. After 270 days, 60% of hydrocarbons had been removed in all microcosms irrespective of the H. diversicolor addition. However, 16S-rRNA gene and 16S-cDNA T-RFLP and RT-PCR-amplicon libraries analysis showed an effect of the condition on the bacterial community structure, composition, and dynamics, supported by PerMANOVA analysis. The 16S-cDNA libraries from microcosms where H. diversicolor was added (oiled and un-oiled) showed a marked dominance of sequences related to Gammaproteobacteria. However, in the oiled-library sequences associated to Deltaproteobacteria and Bacteroidetes were also highly represented. The 16S-cDNA libraries from oiled-microcosms (with and without H. diversicolor addition) revealed two distinct microbial communities characterized by different phylotypes associated to known hydrocarbonoclastic bacteria and dominated by Gammaproteobacteria and Deltaproteobacteria. In the oiled-microcosms, the addition of H. diversicolor reduced the phylotype-richness, sequences associated to Actinobacteria, Firmicutes and Plantomycetes were not detected. These observations highlight the influence of the bioturbation on the bacterial community structure without affecting the biodegradation capacities

Prison : l’inamovible objet

À l’occasion du cinquantième anniversaire de la revue Criminologie, le présent texte présente une rétrospective des articles consacrés à la prison, ayant comme objectif de souligner la contribution des auteurs au développement de la recherche sur les institutions carcérales. En utilisant les publications de la revue pour seules références, l’article propose un choix de différentes thématiques afin d’illustrer les tendances qui se dégagent de ce corpus. Sont ainsi présentés des textes portant sur les origines de la prison et ses incarnations au Québec et au Canada, la volonté de transformer le régime carcéral par la reconnaissance des droits des détenus, la reconstruction de la personne carcérale sous le prisme du risque, ainsi que la situation particulière des femmes incarcérées.On the occasion of the fiftieth anniversary of Criminologie, this article takes a retrospective look at its publications on prisons to highlight the contribution Criminologie authors have made to the development of research on institutions that deal with incarceration. Different topics that illustrate the most important tendencies in this body of work are discussed, including the origins of prison and their incarnations in Quebec and Canada, attempts to transform the prison regime based on recognition of detainee rights, a new understanding of detainees as seen through the prism of risk, and the special situation of incarcerated women.Con ocasión del cincuenta aniversario de la revista Criminologie, el presente texto presenta una retrospectiva de los artículos consagrados a la cárcel, con el objetivo de subrayar la contribución de los autores al desarrollo de la investigación sobre las instituciones carcelarias. Utilizando las publicaciones de la revista para usar solamente las referencias, el artículo propone una selección de diferentes temáticas con el fin de ilustrar las tendencias que se derivan de este cuerpo. Son así presentados unos textos que tratan sobre los orígenes de la cárcel y sus encarnaciones en Quebec y en Canadá, sobre la voluntad de transformar el régimen carcelario por el reconocimiento de los derechos de los detenidos, sobre la reconstrucción de la persona carceral bajo el prisma del riesgo, así como sobre la situación particular de las mujeres encarceladas

21. La Grille d’orientation vers un programme d’encadrement intensif

Depuis l’entrée en vigueur de la Loi sur la protection de la jeunesse (LPJ) en janvier 1979, l’hébergement d’enfants et d’adolescents dans des centres de réadaptation qui comportent un encadrement sécuritaire ou intensif n’a cessé de susciter des controverses, voire des affrontements sur les plans juridique et social. Au risque d’être réductionniste, on peut considérer que dans ce débat s’opposent, d’une part, les droits fondamentaux des enfants placés qui restent protégés par les chartes can..

Le risque criminel est-il objectivable?

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