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1.
BMC Med Educ ; 23(1): 745, 2023 Oct 10.
Article in English | MEDLINE | ID: mdl-37817205

ABSTRACT

BACKGROUND: Problem-based learning (PBL) is a pedagogy involving self-directed learning in small groups around case problems. Group function is important to PBL outcomes, but there is currently poor scaffolding around key self-reflective practices that necessarily precedes students' and tutors' attempts to improve group function. This study aims to create a structured, literature-based and stakeholder-informed tool to help anchor reflective practices on group function. This article reports on the development process and perceived utility of this tool. METHODS: Tool development unfolded in four steps: 1) a literature review was conducted to identify existent evaluation tools for group function in PBL, 2) literature findings informed the development of this new tool, 3) a group of PBL experts were consulted for engagement with and feedback of the tool, 4) four focus groups of stakeholders (medical students and tutors with lived PBL experiences) commented on the tool's constructs, language, and perceived utility. The tool underwent two rounds of revisions, informed by the feedback from experts and stakeholders. RESULTS: Nineteen scales relating to group function assessment were identified in the literature, lending 18 constructs that mapped into four dimensions: Learning Climate, Facilitation and Process, Engagement and Interactivity, and Evaluation and Group Improvement. Feedback from experts informed the addition of missing items. Focus group discussions allowed further fine-tuning of the organization and language of the tool. The final tool contains 17 descriptive items under the four dimensions. Users are asked to rate each dimension holistically on a 7-point Likert scale and provide open comments. Researchers, faculty, and students highlighted three functions the tool could perform: (1) create space, structure, and language for feedback processes, (2) act as a reference, resource, or memory aid, and (3) serve as a written record for longitudinal benchmarking. They commented that the tool may be particularly helpful for inexperienced and poor-functioning groups, and indicated some practical implementation considerations. CONCLUSION: A four-dimension tool to assist group function reflection in PBL was produced. Its constructs were well supported by literature and experts. Faculty and student stakeholders acknowledged the utility of this tool in addressing an acknowledged gap in group function reflection in PBL.


Subject(s)
Education, Medical, Undergraduate , Students, Medical , Humans , Curriculum , Education, Medical, Undergraduate/methods , Learning , Problem-Based Learning/methods
2.
J Immunol ; 168(1): 290-7, 2002 Jan 01.
Article in English | MEDLINE | ID: mdl-11751973

ABSTRACT

In sensitized individuals birch pollen induces an allergic response characterized by IgE-dependent mast cell degranulation of mediators, such as alpha-chymase and other serine proteases. In birch and other plant pollens, a major allergen is profilin. In mammals, profilin homologues are found in an intracellular form bound to cytoskeletal or cytosolic proteins or in a secreted form that may initiate signal transduction. IgE specific to birch profilin also binds human profilin I. This cross-reactivity between airborne and endogenous proteins may help to sustain allergy symptoms. The current work demonstrates that cultured mast cells constitutively secrete profilin I, which is susceptible to degranulation-dependent proteolysis. Coincubation of chymase-rich BR mastocytoma cells with Ala-Ala-Pro-Phe-chloromethylketone (a chymase inhibitor) blocks profilin cleavage, which does not occur in degranulated HMC-1 mast cells, which are rich in tryptase, but chymase deficient. These data implicate chymase as the serine protease cleaving secreted mast cell profilin. Sequencing of chymase-cleaved profilins reveals hydrolysis at Tyr(6)-Val(7) and Trp(35)-Ala(36) in birch profilin and at Trp(32)-Ala(33) in human profilin, with all sites lying within IgE-reactive epitopes. IgE immunoblotting studies with sera from birch pollen-allergic individuals demonstrate that cleavage by chymase attenuates binding of birch profilin to IgE. Thus, destruction of IgE-binding epitopes by exocytosed chymase may limit further mast cell activation by this class of common plant allergens, thereby limiting the allergic responses in sensitized individuals.


Subject(s)
Betula/immunology , Contractile Proteins , Immunoglobulin E/immunology , Mast Cells/immunology , Microfilament Proteins/immunology , Pollen/immunology , Serine Endopeptidases/physiology , Allergens/chemistry , Allergens/immunology , Allergens/metabolism , Amino Acid Sequence , Animals , Binding Sites, Antibody , Cell Degranulation , Cell Line , Chymases , Dogs , Epitopes/chemistry , Epitopes/immunology , Epitopes/metabolism , Humans , Immunoblotting , Mast Cells/enzymology , Microfilament Proteins/chemistry , Microfilament Proteins/metabolism , Models, Molecular , Molecular Sequence Data , Profilins , Serine Endopeptidases/metabolism , Tumor Cells, Cultured
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