Les représentations de l'histoire des sciences chez les élèves du secondaire

Québec Université Laval, Bibliothèque 201

Syndrome de Bean chez l'enfant: à propos de deux cas

L'angiomatose diffuse ou syndrome de Bean est une entité rare caractérisée par des malformations veineuses essentiellement cutanées et digestives pouvant se compliquer d'hémorragie de gravité variable. Notre travail intéresse l'étude de deux enfants, l'un âgé de 5 ans et l'autre de 9 ans et demi atteints d'angiomatose diffuse suivis au service des urgences chirurgicales pédiatriques depuis des années. Le diagnostic a été évoqué devant des rectorragies et/ou des mélénas occasionnant une anémie sévère nécessitant des transfusions régulières chez nos deux patients ainsi que l'apparition des angiomes cutanés au niveau des membres. Les explorations radiologiques ont révélé la présence au niveau du jéjunum et l'iléon des multiples lésions correspondant à une angiomatose grêlique diffuse pour l'enfant de 9 ans et demi; elles n'ont pas retrouvé de localisations abdominales pour l'enfant de 5ans. Les deux malades ont été admis au bloc opératoire avec individualisation à l'exploration des angiomes dont certains saignaient activement. Une résection par entérotomie a été réalisée. Les suites ont été marquées par l'arrêt des saignements. L'intérêt de notre travail est de mettre le point sur cette entité pathologique rare, ainsi que le bénéfice du traitement chirurgical pour le contrôle des complications de cette pathologie et pour la diminution de la fréquence des transfusions

Rotavirus infection activates the UPR but modulates its activity

<p>Abstract</p> <p>Background</p> <p>Rotaviruses are known to modulate the innate antiviral defense response driven by IFN. The purpose of this study was to identify changes in the cellular proteome in response to rotavirus infection in the context of the IFN response. We also sought to identify proteins outside the IFN induction and signaling pathway that were modulated by rotavirus infection.</p> <p>Methods</p> <p>2D-DIGE and image analysis were used to identify cellular proteins that changed in levels of expression in response to rotavirus infection, IFN treatment, or IFN treatment prior to infection. Immunofluorescence microscopy was used to determine the subcellular localization of proteins associated with the unfolded protein response (UPR).</p> <p>Results</p> <p>The data show changes in the levels of multiple proteins associated with cellular stress in infected cells, including levels of ER chaperones GRP78 and GRP94. Further investigations showed that GRP78, GRP94 and other proteins with roles in the ER-initiated UPR including PERK, CHOP and GADD34, were localized to viroplasms in infected cells.</p> <p>Conclusions</p> <p>Together the results suggest rotavirus infection activates the UPR, but modulates its effects by sequestering sensor, transcription factor, and effector proteins in viroplasms. The data consequently also suggest that viroplasms may directly or indirectly play a fundamental role in regulating signaling pathways associated with cellular defense responses.</p

"Start with where you are": The View of Indigenizing STEM Curriculum from Educational Outreach

Draft of conference paperAs educational institutions in Canada respond to the Truth and Reconciliation Commission’s 2015 “Calls-to-Action” by exploring what it means to “indigenize” curriculum, the process is complex and requires contributions from multiple angles of education, including informal education. This is particularly important for STEM education, where the exclusivity of western-centric notions of science and technology must be re-evaluated to provide a more culturally-aware offering. The unique position of informal education programs like educational outreach provides a unique outlook that offers lessons that formal education can benefit from. To explore this unique position in indigenizing, we use a qualitative study with Geering Up, a STEM educational outreach program at the University of British Columbia, and members of K’omoks First Nation on nearby Vancouver Island. We conducted semi-structured interviews with 10 members of Geering Up and 4 members of K’omoks First Nation, and identified themes that ought to inform how educators and scholars consider the foundations of indigenizing curriculum and education in general, particularly the value of sharing. We explore its potential as the foundation of a broad framework for indigenizing curriculum in a way that scales from one community’s perspective to multiple in a way that is respectful, and accounts for the significant time, energy, and human resource commitment involved in these practices.Funding for this research was provided by the Interinstitutional Consortium for Indigenous Knowledge and Penn State University

STEM Educational Outreach and Indigenous Culture: (Re)Centering for Design Scholarship

Integrating Indigenous culture into STEM education is a critical process in building pathways to justice and diversifying design. This process serves to (re)center our conceptions of STEM education by challenging strictly Western notions of STEM, representing an opportunity for learning not just in curricular design, but in technological design as well. Postcolonial computing scholars have critically examined design processes, highlighting the dominance of Western knowledge undergirding cross-cultural design. However, such efforts have yet to fully leverage insights from national curricular (re) centering initiatives. We take up this opportunity through a qualitative case study of an educational outreach organization in British Columbia, Canada, a subsidiary of a nation-wide effort in curricular integration of Indigenous and Western STEM material. Applying postcolonial computing thought, we offer enrichments to theory by providing an empirical basis for a) integrating resiliency, b) politicization in design, and c) arguments for (re)centering epistemological authority in computing. These contributions both enrich theory and enhance the practice of cross-cultural design by encouraging and exploring an Indigenous (re)centering of our understanding of both curricular and technological design

INTERET DE LA LAPAROSCOPIE DANS LE REFLUX GASTRO-OESOPHAGIEN CHEZ L’ENFANT : A PROPOS DE 90 CAS

La pathologie de la jonction oesogastrique chez l’enfant peut revêtir des aspects variés, allant de la malposition cardio-tubérositaire mineure à la grande hernie hiatale. La gravité de l’affection réside dans le risque de reflux gastro-oesophagien par perturbation des mécanismes physiologiques de la continence oesogastrique. Le traitement chirurgical de la pathologie repose sur la mise en place d’un système anti-reflux ou la fundoplicature qui se fait de plus en plus par coelioscopie. L’objectif de notre travail est de rapporter les résultats à court et à long terme de la coelioscopie dans la cure de la hernie hiatale chez l’enfant en se basant sur une série de 90 cas colligés au service des urgences chirurgicales pédiatriques de Rabat en les comparants aux séries de la littérature, ainsi qu’une étude comparative des résultats de notre série avec ceux de 84 patients porteurs de RGO opérés par voie conventionnelle dans le même service

Human enteroids: Preclinical models of non-inflammatory diarrhea

Researchers need an available and easy-to-use model of the human intestine to better understand human intestinal physiology and pathophysiology of diseases, and to offer an enhanced platform for developing drug therapy. Our work employs human enteroids derived from each of the major intestinal sections to advance understanding of several diarrheal diseases, including those caused by cholera, rotavirus and enterohemorrhagic Escherichia coli. An enteroid bank is being established to facilitate comparison of segmental, developmental, and regulatory differences in transport proteins that can influence therapy efficacy. Basic characterization of major ion transport protein expression, localization and function in the human enteroid model sets the stage to study the effects of enteric infection at the transport level, as well as to monitor potential responses to pharmacological intervention

A single nanobody neutralizes multiple epochally evolving human noroviruses by modulating capsid plasticity

Acute gastroenteritis caused by human noroviruses (HuNoVs) is a significant global health and economic burden and is without licensed vaccines or antiviral drugs. The GII.4 HuNoV causes most epidemics worldwide. This virus undergoes epochal evolution with periodic emergence of variants with new antigenic profiles and altered specificity for histo-blood group antigens (HBGA), the determinants of cell attachment and susceptibility, hampering the development of immunotherapeutics. Here, we show that a llama-derived nanobody M4 neutralizes multiple GII.4 variants with high potency in human intestinal enteroids. The crystal structure of M4 complexed with the protruding domain of the GII.4 capsid protein VP1 revealed a conserved epitope, away from the HBGA binding site, fully accessible only when VP1 transitions to a “raised” conformation in the capsid. Together with dynamic light scattering and electron microscopy of the GII.4 VLPs, our studies suggest a mechanism in which M4 accesses the epitope by altering the conformational dynamics of the capsid and triggering its disassembly to neutralize GII.4 infection.Instituto de VirologíaFil: Salmen, Wilhelm. Baylor College of Medicine. Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology; Estados UnidosFil: Hu, Liya. Baylor College of Medicine. Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology; Estados UnidosFil: Bok, Marina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virología e Innovaciones Tecnologicas; ArgentinaFil: Bok, Marina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Chaimongkol, Natthawan. National Institutes of Health. National Institute of Allergy and Infectious Diseases. Caliciviruses Section; Estados UnidosFil: Ettayebi, Khalil. Baylor College of Medicine. Department of Molecular Virology and Microbiology; Estados UnidosFil: Sosnovtsev, Stanislav V. National Institutes of Health. National Institute of Allergy and Infectious Diseases. Caliciviruses Section; Estados UnidosFil: Soni, Kaundal. Baylor College of Medicine. Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology; Estados UnidosFil: Ayyar, B. Vijayalakshmi. Baylor College of Medicine. Department of Molecular Virology and Microbiology; Estados UnidosFil: Shanker, Sreejesh. Baylor College of Medicine. Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology; Estados UnidosFil: Neill, Frederick H. Baylor College of Medicine. Department of Molecular Virology and Microbiology; Estados UnidosFil: Sankaran, Banumathi. Berkeley Center for Structural Biology. Molecular Biophysics and Integrated Bioimaging. Lawrence Berkeley Laboratory; Estados UnidosFil: Atmar, Robert L. Baylor College of Medicine. Department of Molecular Virology and Microbiology; Estados UnidosFil: Atmar, Robert L. Baylor College of Medicine. Department of Medicine; Estados UnidosFil: Estes, Mary K. Baylor College of Medicine. Department of Molecular Virology and Microbiology; Estados UnidosFil: Estes, Mary K. Baylor College of Medicine. Department of Medicine; Estados UnidosFil: Green, Kim Y. National Institutes of Health. National Institute of Allergy and Infectious Diseases. Caliciviruses Section; Estados UnidosFil: Parreño, Gladys Viviana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virologia e Innovaciones Tecnologicas (IVIT); ArgentinaFil: Parreño, Gladys Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Prasad, B. V. Venkataram. Baylor College of Medicine. Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology; Estados UnidosFil: Prasad, B. V. Venkataram. Baylor College of Medicine. Department of Molecular Virology and Microbiology; Estados Unido