L'an 2440 : rêve s'il en fut jamais de Louis-Sébastien Mercier : une étude thématique

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal

Platelet alpha-granules contribute to organ-specific pathologies in a mouse model of severe malaria

Cerebral malaria (CM) and malaria-associated acute lung injury/acute respiratory distress syndrome (MA-ALI/ARDS) are among the most severe complications of Plasmodium infection. While these disease manifestations are multifactorial, platelets have been described to play a role in the development of both syndromes in humans1,2 and mice3,4. Although the impact of platelets on malaria has been well-studied, questions remains with regard to their contribution to parasite control and immunopathogenesis. Studies have indicated that platelets can kill Plasmodium-infected red blood cells (iRBCs)5-8. However, there are contrasting reports that platelets do not exert any significant control over parasite growth but rather exacerbate malaria immunopathology3,9-12. In this study, we address the role of platelets in the development of severe malaria in three different mouse models of platelet dysfunction/depletion. We show a key role for platelets, and particularly platelet alpha granules (-granules), in mediating organ-specific pathologies during rodent Plasmodium infection

How Accessible Was Information about H1N1 Flu? Literacy Assessments of CDC Guidance Documents for Different Audiences

We assessed the literacy level and readability of online communications about H1N1/09 influenza issued by the Centers for Disease Control and Prevention (CDC) during the first month of outbreak. Documents were classified as targeting one of six audiences ranging in technical expertise. Flesch-Kincaid (FK) measure assessed literacy level for each group of documents. ANOVA models tested for differences in FK scores across target audiences and over time. Readability was assessed for documents targeting non-technical audiences using the Suitability Assessment of Materials (SAM). Overall, there was a main-effect by audience, F(5, 82) = 29.72, P<.001, but FK scores did not vary over time, F(2, 82) = .34, P>.05. A time-by-audience interaction was significant, F(10, 82) = 2.11, P<.05. Documents targeting non-technical audiences were found to be text-heavy and densely-formatted. The vocabulary and writing style were found to adequately reflect audience needs. The reading level of CDC guidance documents about H1N1/09 influenza varied appropriately according to the intended audience; sub-optimal formatting and layout may have rendered some text difficult to comprehend

A chicken bioreactor for efficient production of functional cytokines

The global market for protein drugs has the highest compound annual growth rate of any pharmaceutical class but their availability, especially outside of the US market, is compromised by the high cost of manufacture and validation compared to traditional chemical drugs. Improvements in transgenic technologies allow valuable proteins to be produced by genetically-modified animals; several therapeutic proteins from such animal bioreactors are already on the market after successful clinical trials and regulatory approval. Chickens have lagged behind mammals in bioreactor development, despite a number of potential advantages, due to the historic difficulty in producing transgenic birds, but the production of therapeutic proteins in egg white of transgenic chickens would substantially lower costs across the entire production cycle compared to traditional cell culture-based production systems. This could lead to more affordable treatments and wider markets, including in developing countries and for animal health applications. Here we report the efficient generation of new transgenic chicken lines to optimize protein production in eggs. As proof-of-concept, we describe the expression, purification and functional characterization of three pharmaceutical proteins, the human cytokine interferon α2a and two species-specific Fc fusions of the cytokine CSF1. Our work optimizes and validates a transgenic chicken system for the cost-effective production of pure, high quality, biologically active protein for therapeutics and other applications

Phenological mismatch in Arctic-breeding shorebirds: Impact of snowmelt and unpredictable weather conditions on food availability and chick growth

The ecological consequences of climate change have been recognized in numerous species, with perhaps phenology being the most well-documented change. Phenological changes may have negative consequences when organisms within different trophic levels respond to environmental changes at different rates, potentially leading to phenological mismatches between predators and their prey. This may be especially apparent in the Arctic, which has been affected more by climate change than other regions, resulting in earlier, warmer, and longer summers. During a 7-year study near Utqiaġvik (formerly Barrow), Alaska, we estimated phenological mismatch in relation to food availability and chick growth in a community of Arctic-breeding shorebirds experiencing advancement of environmental conditions (i.e., snowmelt). Our results indicate that Arctic-breeding shorebirds have experienced increased phenological mismatch with earlier snowmelt conditions. However, the degree of phenological mismatch was not a good predictor of food availability, as weather conditions after snowmelt made invertebrate availability highly unpredictable. As a result, the food available to shorebird chicks that were 2–10 days old was highly variable among years (ranging from 6.2 to 28.8 mg trap−1 day−1 among years in eight species), and was often inadequate for average growth (only 20%–54% of Dunlin and Pectoral Sandpiper broods on average had adequate food across a 4-year period). Although weather conditions vary among years, shorebirds that nested earlier in relation to snowmelt generally had more food available during brood rearing, and thus, greater chick growth rates. Despite the strong selective pressure to nest early, advancement of nesting is likely limited by the amount of plasticity in the start and progression of migration. Therefore, long-term climatic changes resulting in earlier snowmelt have the potential to greatly affect shorebird populations, especially if shorebirds are unable to advance nest initiation sufficiently to keep pace with seasonal advancement of their invertebrate prey

Parliament and the war prerogative in the United Kingdom and Canada: Explaining variations in institutional change and legislative control

The British and Canadian Parliaments have no legal control over military deployment decisions. Recently, however, governments in both countries have held votes in the House of Commons on expeditionary missions involving combat. In the United Kingdom, this has led to a convention of legislative control of the executive's prerogative to deploy the armed forces. In Canada, the votes have benefited and enabled the executive, rather than strengthening legislative control. Using Mahoney and Thelen's (2010)theory of gradual institutional change, this article analyses how and why war prerogative reforms in the United Kingdom and Canada have resulted in different outcomes

Royal Succession and the Constitutional Politics of the Canadian Crown, 1936–2013

Canadian governments held opposite views on how to alter the laws of royal succession for Canada in 1936 and 2013. This contrast was not the result of refined thinking about how the law of succession operates in Canada. Rather, the difference is explained by these governments’ political aims and institutional constraints. In 1936, the government of William Lyon Mackenzie King denied that Canada necessarily followed the British line of succession, and he ensured that alterations to the rules of succession that followed the abdication of King Edward VIII were extended into Canadian law. This was done gradually to advance the cause of Canadian autonomy while maintaining the unity of the Crown in the Commonwealth. In 2013, the government of Stephen Harper argued that rules of royal succession were not a matter of Canadian law or a constitutional issue in Canada. Instead, the Harper government maintained that Canada automatically accepts the British monarch as the sovereign of Canada. This approach served to avoid the complex constitutional amending formula Canada adopted in 1982. Constitutional politics, not the law of the constitution, explains how these two Canadian governments fundamentally disagreed with each other over royal succession