The progression from HIV infection to AIDS occurs because the body’s immune system fails to control replication of the virus. While broadly neutralizing antibodies (bNtAb) are unable to clear an established infection, they have shown promise in providing protection against the contraction of HIV. However bNtAb have proven to be extremely difficult to generate by immunization. Marinieve Montero is studying the antigenicity and immunogenicity of the HIV-1 transmenbrane glycoprotein gp41, to which several bNtAb are directed. Her work will involve an exhaustive biochemical characterization of the gp41 protein presentation in the context of membranes, and the analysis of the bNtAb response generated after immunization of animals. The results from her study will improve the understanding of the biology of bNtAb production, and may be a valuable aid in the design of successful vaccine candidates and immunization methods.
Program: Trainee
Molecular dissection of neural stem cells
Damage to the central nervous system caused by conditions such as Alzheimer’s disease, Parkinson’s disease, stroke and spinal cord injuries was once considered irreversible. But recent scientific advances suggest neural stem cells may hold the key to restoring the damaged area of the brain, giving hope to people suffering from these devastating conditions. Scientists have discovered that transplanted neural stem cells have the ability to reproduce themselves and become mature cells capable of performing nervous system functions. However, isolating these cells has proven difficult since researchers have yet to find markers that identify neural stem cells. Barbara Murdoch is working to identify proteins specific to the surface of neural stem cells so she can study their growth requirements. By solving this puzzle, scientists will be able to more effectively use neural stem cells for therapies that promote nervous system recovery.
Developmental changes in pain expression in infants
Assessing infant pain for clinical or research purposes is challenging because infants are unable to talk about their pain. However, infants can communicate distress and pain in a number of ways, including facial activity, body movement, crying and changes in physiological responses. Rami Nader is studying how pain expression changes during the first year of life, when infants undergo a particularly rapid rate of growth and development. He is also investigating the link between parents’ assessments of pain and factors that influence those assessments. Improved understanding of how infant pain expression changes and what influences parents’ reports of pain will contribute to refinement and development of more developmentally appropriate measures of pain.
The role of intraepithelial lymphocytes in cutaneous immunity and in the generation of psoriasiform pathology
Seborrheic dermatitis and psoriasis are chronic, inflammatory skin conditions that are extremely difficult to treat. Despite extensive research, the cause of these conditions is not known, although they have been linked to impairment of normal immunological response. Darryl Oble is investigating whether a genetic defect that renders cells unable to signal the immune system to repair damage predisposes people to developing inflammatory skin conditions. Similar genetic issues are involved in other immunologically-based diseases, such as Type 1 diabetes, inflammatory bowel disease, cancer and other conditions. As a result, this research could help explain how these diseases develop, lead to more successful treatments for a variety of conditions and reduce side effects.
Understanding low-income mothers' efforts to provide safe home environments for young children
Unintentional injuries represent the leading cause of death for children and youth under the age of 20. For children under five, approximately half of all deaths due to unintentional injuries occur in and around the home. Research shows that children living in low-income families are at greatest risk for home injuries. Studies also show that parental attitudes towards safety issues vary greatly, and that there are discrepancies between attitudes and taking action to prevent injuries. However, little is known about parents’ underlying values about safety and injury risks to young children and how these values fit into the broader social context of children and safety issues. Lise Olsen is exploring low-income mothers’ experiences with safety issues in the home. Using ethnographic methods, including interviews and observations, the study will provide insight about the everyday challenges of keeping young children safe from injuries at home. Ultimately, Lise hopes the research contributes to the design of appropriate and relevant injury prevention programs and policies.
Enhancing access to health care for marginalized groups through a study of relationships between street nurses and the people they serve
In previous research, people experiencing marginalization such as those living with mental illness, HIV/AIDS, illicit drug use and homelessness have reported very negative experiences with the health care system. These experiences can result in delays seeking treatment and greater future costs to the health care system. At the same time, these groups have reported positive experiences with street nurses (registered nurses who work on the street). Bernadette Pauly is assessing the nature and quality of health care relationships between street nurses and their clients, and how health and social policies and organizational structures affect these relationships. Increasing understanding of these relationships, along with factors in the environment where street nurses provide care, could ultimately reveal ways to improve health care delivery for marginalized groups and, ultimately, their health.
Agonist-specific Ca2+ signalling micro-domains in vascular smooth muscle cytoplasm and mitochondria
Building on his earlier research, which was supported by a MSFHR Trainee Award, Damon Poburko is now investigating the mechanisms involved in mitochondrial regulation of calcium. An average cell has several hundred mitochondria, which provide the energy for cells to function properly. Research has shown mitochondria are involved in programmed cell death, or apoptosis, when they take up large, toxic loads of calcium. In addition, mitochondria sense calcium changes, allowing them to tailor energy production to cell needs. Mitochondria also help regulate intracellular calcium levels, which determine blood vessel constriction in vascular muscle. The findings should help explain how vascular tone is regulated, and how blood is shunted to different parts of the body as needed. Ultimately, this research may lead to the development of new therapies to treat vascular diseases.
The Development of Joint Attention within Parent-infant Interaction
The development of children’s thinking and successful participation in healthy social interaction depends on their ability to share attention with others. Called joint attention, this ability begins to emerge by a child’s first birthday and enables them to learn about people, language and ways of thinking. Infants in whom this developmental milestone is delayed are often from at-risk groups, such as low birth weight children. The delay is also associated with autism, Attention Deficit Hyperactivity Disorder and language impairment. By studying observable aspects of joint attention, Timothy Racine is testing whether the parent-child relationship affects its development. In particular, he aims to identify the age at which infants begin to direct others’ attention with pointing gestures, and whether parents with a supportive style of interacting have infants who point meaningfully at an earlier age. Results from the study could help in the education and training of parents on appropriate ways of establishing joint attention in both normally developing and at-risk infants.
Examining physical perceptions of the body and physical characteristics as predictors of physical activity during adolescence
Research shows that a growing number of Canadian adolescents are becoming less active, threatening their physical and mental health by increasing their risk of being overweight. While there has been substantial research on physical activity, the primary factors that influence levels of activity have not been identified. Catherine Sabiston’s past research has focused on ways adolescents and young adults deal with feelings and emotions related to their body. In this research, she has found initial links between body image and physical activity. She is now looking at whether body image (perceptions and attitudes about one’s body and physical appearance) and actual body characteristics related to shape and weight contribute to decreasing physical activity levels among adolescents. Catherine is also interested in how these factors affect boys and girls differently. Her goal is to come up with realistic recommendations that will lead Canadian adolescents toward increased activity levels and eventually healthier lifestyles.
Anoxia and the regulation of intracellular ion concentrations in hippocampal neurons
Neurons (nerve cells) need a regular supply of oxygen and nutrients to survive. When neurons are deprived of these essential factors for more than a few minutes, such as during a stroke or cardiac arrest, they undergo changes that lead to cell death. Intracellular concentrations of ions (e.g. sodium ions, calcium ions and protons) show dramatic changes during and following periods of anoxia or ischemia (oxygen deprivation). These changes play an important role in determining subsequent neuronal damage or death. Claire Sheldon is characterizing these anoxia-evoked changes in sodium ions, calcium ions and protons in hippocampal neurons and hopes to identify the mechanisms which contribute to their production. Her research focuses on the role(s) of intracellular pH regulating mechanisms to the changes observed, with particular emphasis on the Na+/H+ exchanger, an acid-extruding mechanism present in hippocampal neurons. Claire hopes her research will lead to new strategies to prevent or limit neuron death and the debilitating effects that stroke or cardiac arrest have on the central nervous system.