6 research outputs found
The role of humoral autoimmunity in gastrointestinal neuromuscular diseases.
No full textDysfunction of the gastrointestinal neuromuscular apparatus (including interstitial cells of Cajal) is presumed to underlie a heterogeneous group of disorders collectively termed gastrointestinal neuromuscular diseases (GINMDs). There is increasing experimental and clinical evidence that some GINMDs are immune-mediated, with cell-mediated dysfunction relatively well studied. Humoral (antibody)-mediated autoimmunity is associated with several well-established acquired neuromuscular diseases and is now implicated in an increasing number of less well-characterised disorders, particularly of the central nervous system. The role of autoimmunity in GINMDs has been less studied. Whilst most work has focused on the presence of antibodies directed to nuclear antigens, particularly in the context of secondary disorders such as paraneoplastic intestinal pseudo-obstruction, the possibility that 'functional' anti-neuronal antibodies directed to membrane-bound ion channels may cause disease (channelopathy) is now also being realised. The evidence for humoral autoimmunity as an etiologic factor in primary (idiopathic) and secondary GINMDs is systematically presented using the original paradigms previously applied to established autoimmune neuromuscular disorders. The presence of anti-enteric neuronal antibodies, although repeatedly demonstrated, still requires the identification of specific neuronal autoantigens and validated evidence of pathogenicity
The role of humoral autoimmunity in gastrointestinal neuromuscular diseases
No full textPhDDysfunction of the gastrointestinal neuromuscular apparatus (including interstitial cells of Cajal) is presumed to underlie a heterogeneous group of disorders collectively termed gastrointestinal neuromuscular diseases (GINMDs). Humoral (antibody)-mediated autoimmunity directed against ligand- or voltage-gated ion channels or associated proteins involved in neuromuscular transmission is associated with several acquired neuromuscular diseases of the periphery and is now implicated in an increasing number of less well-characterised diseases. Anti-channel antibodies have been reported in small numbers of patients with GINMD, particularly in those with GI dysfunction secondary to an underlying disease such as neoplasia or infection. However, little is known of humoral autoimmunity in primary GINMDs.
This thesis investigated the association between anti-channel antibodies and GINMD, and the human GI tract as a potential target of anti-channel antibodies. The presence of anti-voltage- and ligand-gated antibodies was investigated in the serum of patients with primary achalasia, enteric dysmotility and intestinal pseudo-obstruction, and in those with GINMD secondary to Chagas’ disease. The functional effect of sera from some of these patients on colonic smooth muscle contractility was also characterised. Finally, the distribution of six voltage-gated potassium channels (VGKCs), which serve essential roles in the peripheral and central nervous systems and are known targets of pathological autoantibodies, were investigated in all layers of the human GI tract.
Our findings suggest that currently recognised anti-channel antibodies are not a common pathogenic factor in primary GINMDs. Anti-channel antibodies, in particular anti-VGKC antibodies, were however found in a significant number of individuals with Chagas’ disease. Furthermore, circulating factors in patients with chagasic GI disease altered GI smooth muscle contractility in vitro which may have pathological relevance to GI dysfunction. VGKCs were found throughout the human GI tract, especially in enteric neurons and epithelial cells, which has significance for both normal function and in relation to the GI tract as a target organ for anti-channel autoimmunity
Serum but Not IgG From Patients With Chagas' Disease Relax Naive Human Colon Muscle Without Directly Interfering With Motor Nerve Functions
No full textAssessment and evaluation practices in a pediatric dentistry clinical education setting
No full textIn clinical teaching and learning settings, there is a need for assessment and evaluation practices to be focused on students' overall performance during patient care, not just technical skills in Dentistry. Competency-based education is intended to provide the framework for dental education at The University of British Columbia (UBC) in terms of curriculum content and assessment of student learning outcomes. Clinical instruction in disciplines such as Pediatric Dentistry depends on clinical practitioner-instructors who have potential to make important contributions to student development. Although they bring strengths as disciplinary experts immersed in the realities of dental practice, most are not well versed in research-based instructional strategies to engage students in critical thinking and self-directed learning for the rigours of independent practice.
In a qualitative study, data were collected by the author (resident Program Coordinator of the UBC Children's Dental Program) through interviews, observation in teaching clinics, and review of documentation to inform the scope and nature of assessment and evaluation practices in the clinical educational settings of Pediatric Dentistry at UBC. Interview data also provided reflections about how clinical practitioner-instructors understand their practice. Data collected were analyzed using principles of grounded theory and merged into themes drawn from the conceptual framework of Hubball and Burt (2004) as well as the use of the UBC Faculty of Dentistry patient care performance criteria and standards for student learning.
Assessment and evaluation practices in clinical settings typically ranged from predominantly directive methods (e.g. traditional teacher-driven and skills-based) that clinical practitioner-instructors experienced themselves as students, to occasional learning-centred methods (e.g. instructor questioning, self-analysis, and reflection) supported by current literature. While clinical practitioner-instructors recognized the importance of student confidence and safety of patient care, most were unfamiliar with authentic methods of assessment and evaluation for competency-based dental education. Further, there was little reflection or collaboration within the community of practitioners about the effectiveness of assessment methods.
These results and a research-informed approach will guide planning of faculty development initiatives (e.g., learning communities focused on learning-centred assessment and evaluation strategies) for clinical practitioner-instructors.Education, Faculty ofCurriculum and Pedagogy (EDCP), Department ofGraduat
Esophageal Epithelial ASIC3 is Associated With Increase in Severity of Symptoms in Patients With Gastro-Esophageal Reflux Disease (GERD)
No full textProgramme design practice in a polytechnic in Aotearoa/New Zealand: A case for complexity
No full textA programme is an instrument for education. Through educational programmes we help shape our society. Programme design includes decisions on what society finds valuable for people to learn, and how this should be structured and organised. In this way it influences teaching and learning. Therefore understanding how and on what basis programme design decisions are made is vital for the improvement of teaching and learning. Yet, there is a dearth of research that provides this understanding in the context of tertiary education. This thesis alleviates this scarcity by describing the theorising of design practice of certificate and diploma programmes in a polytechnic in Aotearoa/New Zealand. The research presented in this thesis consists of an interpretive case study of a polytechnic in Aotearoa/New Zealand. The study included embedded case studies of programme design practice at institutional level and of design practice of five certificate and diploma programmes across the polytechnic. Data were analysed from 32 interviews with representatives of the six embedded cases, from documents including the institution’s Academic Statute, its Quality Management system and approved programme documents, and from observation of one meeting. The findings show that programme design practice can be observed through various lenses. For this case study the following seven lenses were identified: 1) The teaching and learning lens shows how language shapes the conceptualisations of a programme and how these conceptualisations relate to views on teaching and learning; 2) The rational lens shows how models and frameworks influence programmes, how these models and frameworks become rationalisations that are often used unconsciously, and what the implications of this are; 3) The cultural lens allows exploring what is considered normal within programme design practice and indicates how differences from the norm are being approached; 4) The personal experience lens highlights how the personal experiences of people involved contribute to programme design considerations and decision-making; 5) The ethical lens investigates how people’s moral and professional responsibilities influence their programme design practice; 6) The business lens illustrates the contribution of business considerations to programme design; and, 7) The social-political lens highlights how people’s formally and informally assigned roles and responsibilities, their political responsibilities, and their negotiations between multiple responsibilities impact on programme design practice. The images of these lenses are interrelated. To create a comprehensive understanding of the images and their interrelationship, a programme has been theorised as a complex system. The constituents of this system are people’s considerations, language, silences, experiences and relationships. These constituents only concern those aspects of education that are assigned to the concept of ‘programme’. For the current case study these aspects were found to consist of six components: consultation for and development of a programme; intentions; structure and instruction; administration and management; assessment; and evaluation of a programme, including elements within these components. The people who create the considerations, language, silences, experiences and relationships were found in this case study to be people within the polytechnic. The complex programme system interacts with the outside world. Programme design practice then is the programme system’s adaptation to influences from outside. Ideological discourses are shown to form the power structures that shape the direction of adaptation of the programme system. For this case study the analysis of the images of the seven lenses and their interconnections shows neo-liberalist discourses as the prevailing ideological discourses determining the direction of adaptation of the complex programme system. The findings of this study have three major implications for practice. Firstly, the effects of a programme on the world around it cannot be predicted or controlled but emerge from the programme system. Secondly, the findings imply that if a programme is to survive or continue to develop, it needs diversification. Further strengthening of the already dominant ideological discourses directing programme systems in the context of this case study risks the death of these systems. And thirdly, acknowledging ideological discourses as the power structures that shape the direction of the adaptation of complex programme systems requires practitioners to be responsible in deciding which discourses to follow and to be mindful of the possible implications of their decisions
