Physical activity provides numerous health benefits, but most Canadian youth are not active enough to receive these benefits. The growing trend of inactivity has serious health implications for youth now and into adulthood. A number of theories on motivation suggest that peer relationships influence adolescents’ motivations and behaviour, but little research has explored the influence of peers on physical activity. Meghan McDonough is surveying 500 high school students to determine the role of peer relationships in physical activity motivation and behaviour. She also aims to identify specific elements of peer relationships that are key influences of physical activity motivation and behaviour. Results from the research could contribute to development of programs that motivate youth to participate in physical activity.
Year: 2004
An analysis of the structure of life satisfaction as an indicator of adolescent quality of life in context of health
Quality of life has become an important outcome of health care practice and research. Quality of life measurements are increasingly being used to determine the appropriateness of various treatment approaches. However, quality of life research has focused primarily on adult and senior populations, with little research examining quality of life among adolescents. In a study targeting adolescents aged 13 to 19 who attend BC high schools, Richard Sawatzky is researching the effectiveness of the Multidimensional Student Life Satisfaction Scale in measuring adolescent quality of life. Using data obtained with the scale, he is examining how differences in perceived and observed physical and psychological health affect adolescents’ perceptions of family life, friendships, school life, living environment and themselves. Health professionals could use findings from the research to develop health promotion initiatives and treatments that address the particular needs of adolescents.
Neuroendocrine Regulation of Aggressive Behaviour and Adult Neuroplasticity
Steroid hormones have profound effects on human physiology and behaviour. They are critical for the nervous system to develop and function normally, and play a role in psychiatric and neurological diseases. The levels of one steroid hormone, DHEA (dehydroepiandrosterone), drop dramatically as people age. DHEA supplements have been promoted in the media as a “fountain of youth” that can reverse brain aging and cognitive decline. However relatively little is known about the actions of DHEA on the nervous sytem and how DHEA acts at the cellular and molecular level. In earlier research, Dr. Soma showed that DHEA increases aggressive behaviour and the size of specific brain regions. Now Dr. Soma is further clarifying the effects of DHEA on behaviour and neuroplasticity (the brain’s natural ability to form new nerve cells and new connections after a change in the environment). He is assessing whether DHEA must be converted to sex steroids such as testosterone and estrogen to affect the brain. The research could improve understanding of the physiological functions of DHEA in humans, and help determine how DHEA treatment could be used to alleviate mental illness and increase neuroplasticity.
Regulation of the BACE gene expression in the Alzheimer's disease pathogenesis
Alzheimer’s disease is the most common neurodegenerative disorder leading to dementia. The disease affects about 10 percent of people over the age of 65, and prevalence increases with age. Approximately $5.5 billion is spent in Canada each year on people with Alzheimer’s and related dementias. Deposits of the amyloid ß(Aß) protein in the brain are a characteristic feature of Alzheimer’s. Four genes, including APP, have also been linked to the disease. Processing of APP by the BACE enzyme is essential to generate the A-beta protein. In previous research Dr. Weihong Song made important discoveries about the role of presenilin proteins in the development of Alzheimer’s Disease. Now Dr. Song, who holds the distinction of being the youngest physician to graduate in China, is researching the role of BACE in the development of Alzheimer’s Disease. The research could contribute to development of BACE inhibitors, which could improve treatment of Alzheimer’s.
The link between cardiovascular and bone health: a randomized controlled trial of statins and exercise rehabilitation in post-menopausal women
Cardiovascular disease (CVD) and osteoporosis are major health problems in North America. CVD is the leading cause of death of North American women, and one in four Canadian women over the age of 50 has osteoporosis. Once a woman reaches menopause, the risk for both osteoporosis and CVD increases substantially. Both diseases were thought to be independent consequences of aging. However, mounting evidence shows links between these diseases. For example, a widely used class of cholesterol lowering drugs, known as statins, reduces atherosclerosis (hardening of the arteries) and also increases bone health. Exercise may also provide the same health benefits, but more than 60 percent of Canadian women between 50 and 70 are not active enough to reduce their risk of heart disease or osteoporosis. Dr. Darren Warburton is studying the combined effect of statins and exercise on cardiovascular and bone health, physical fitness and quality of life. The research could provide important new information to help develop prevention and treatment programs for these diseases in post-menopausal women.
Access issues for Aboriginal people seeking primary care services in an urban centre
Access to primary care is problematic for large numbers of Aboriginal people in BC and other parts of Canada. Because of these difficulties, many Aboriginal people rely on hospital emergency departments for health care. Since emergency departments are not designed to provide comprehensive primary care, there are concerns about health outcomes and continuity of care for patients who rely on them. To plan effective, responsive services, more must be known about the ongoing use of the emergency department for health concerns that could potentially be addressed elsewhere. Dr. Annette Browne and a team of Aboriginal and non-Aboriginal researchers are exploring the factors and social contexts that influence access to primary care from the perspective of Aboriginal patients who seek care at the emergency department. Learning from the perspectives of Aboriginal peoples will be critical to the design of accessible, culturally safe, primary care services. Dr. Browne is also examining how interactions between Aboriginal patients and health professionals affect decisions about where to seek care. Findings from this research will be discussed with leaders in Aboriginal health, policy makers and health care planners to improve access to effective health care services involving Aboriginal peoples.
Neuropsychology of vision and eye movements
Nearly half of the human brain is involved in processing vision and eye movements. These functions can be impaired by strokes or brain tumours, as well as neurological disorders such as schizophrenia and autism. Using imaging technologies, experimental vision tests and eye movement recordings, Dr. Jason Barton is studying how neurological diseases disrupt the brain_s sensory and motor processing systems. Recognizing faces is one of the most demanding tasks for our visual systems, requiring both high-level perception and memory. Faces differ in only subtle ways in structure and shape, and the average person sees hundreds of faces in a day: despite this, humans are able to recognize faces effortlessly. Dr. Barton is studying how face perception is organized in the normal human brain, and how it is disrupted in patients with brain damage from strokes and surgery, and in those with Asperger_s disorder, an autism-like condition. Dr. Barton is also investigating saccades, rapid eye movements that shift our gaze toward a target and antisaccades, an unusual eye movement in which subjects look away from a suddenly appearing target. Performance on novel tasks like antisaccades can tell us something about how we exercise control over our responses to the environment. Abnormalities on such tasks can inform us about the problems with response control in conditions like schizophrenia. These studies will improve our understanding of these neurological disorders, how they disrupt visual processing, and lead to the development of future remedies.
Protein and lipid transport in health and disease: molecular mechanisms of endocytic sorting
Lysosomal storage diseases involve an inherited enzyme deficiency caused by genetic defects. Every cell has hundreds of lysosomes, which contain digestive enzymes used to break down complex cell components such as proteins into simpler components for the cell to reuse. In lysosomal storage diseases fatty substances called sphingolipids accumulate inside brain cells and cause progressive neurological degeneration and early death. Potentially, a lack of digestive enzymes may be the root cause. Recent research also suggests that the way the brain transports cholesterol may contribute to the damage associated with these diseases. The Saccharomyces cerevisiae yeast uses genes that are similar to those found in humans to control the transport of proteins and fats inside the cell. Dr. Elizabeth Conibear is identifying these genes in yeast and in mammalian cells. The research could help reveal ways to change the transport and storage of cholesterol and other lipids, which could lead to methods of preventing accumulation of fatty substances in the brains of children with these diseases. Developing a better understanding of how the cell transports cholesterol could also have important implications for treating adults with heart disease.
Synapse assembly and plasticity
In order to combat neurological disease and mental illness, a greater understanding of how the brain functions at the molecular and cellular level is needed. If we can learn how nerve cells form connections during development, we can develop therapies for regenerating connections following injury. Dr. Ann Marie Craig is leading an effort to understand how nerve cells form and modify synaptic connections. Her group uses a combination of fluorescence imaging, molecular biology, and electrophysiology to investigate how nerve cells communicate. By studying nerve cells growing in a dish, the scientists have already begun to identify molecular signals on the surface of nerve cells that induce contacting partners to form a synaptic connection. Mutations in one of these molecular cues has recently been linked to autism. Dr. Craig and her team are also studying how neurotransmitter receptors are localized and modified to control the strength of synaptic signaling between nerve cells. Given that synapses are the basic units of communication in the brain, the knowledge gained from understanding synapse development and modification has broad implications for the treatment of all neurological diseases and mental illnesses.
Structural studies of clinically-relevant protein-carbohydrate interactions
Thanks to new scientific methods, including use of high-speed computers, the search for ways to diagnose, treat and cure disease has changed greatly in the last 50 years. While chance discoveries are still important, new technology allows researchers to systematically probe the molecular nature of disease-causing organisms and the medicines being developed to treat them. X-ray crystallography is a technique to determine the three-dimensional structure of crystallized molecules. Dr. Stephen Evans is using the technique to study the interactions between proteins (such as antibodies and enzymes) with carbohydrates to learn about the atomic structure of these molecules. In one project Dr. Evans is investigating the antibodies responsible for inherited immunity to learn how the body reacts to new and emerging diseases. In another project he is investigating how a protein molecule can mimic a carbohydrate and be used to vaccinate patients against their own cancer. He is also examining how enzymes can be used to make new carbohydrates that can, in turn, be used as new medicines. Finally, Dr. Evans is developing a new version of his SETOR molecular graphics software that will enable researchers to reduce complicated molecular structures to simplified illustrations.