Magnetic resonance imaging (MRI) is a powerful non-invasive imaging tool due to its ability to provide soft tissue contrast with high spatial resolution. Clinicians and researchers alike value MR images both for diagnosis and characterization of changes cause by disease. Recent advances have been made using MRI to image central nervous system white matter and investigate diseases that affect the white matter (such as Multiple Sclerosis), and damage to the spinal cord. The term âwhite matterâ is derived from the white colour of nerve tracts. It appears white because of the layers of fat wrapped around each nerve fibre, called the âmyelin sheathâ. If the myelin sheath has been degraded or broken down, transmission of information along the fibre can be slowed down or lost completely. In the case of a narrowing of the spinal canal, the invertebral discs slip out of place and put pressure on the spinal cord, damaging the white matter tracts, resulting in symptoms like a feeling of numbness or tingling in the hands or feet. Somatosensory evoked potentials (SSEP) are a current clinical tool used to detect myelin degradation and nerve damage in the spinal cord. However, SSEP measurements are limited to only sensory pathway nerves, and cannot locate damage throughout the entire spinal cord. The UBC MRI Research Group has recently developed an MRI technique to measure myelin content in vivo, termed âmyelin water imagingâ (MWI), which can be applied throughout the brain and spinal cord. Erin MacMillan is applying the MWI technique to healthy adults and people suffering from narrowing of the cervical spinal canal. She hopes to find that MWI provides results consistent with SSEP measurements in sensory pathways, and identifies myelin degradation throughout the cervical spine. In addition, she will compare patient results from before and after surgery in the hopes of finding that the white matter has been repaired. If MWI proves to be an accurate measurement of myelin in the spinal cord, it could potentially be used to track myelin content during new spinal cord injury treatments aimed at degrading myelin in an effort to encourage nerve fibre repair.
Year: 2007
An examination of illicit drug use and sexual risk behaviours among a cohort of street-involved youth in Vancouver
Injection drug use has significant health consequences, including high rates of HIV and hepatitis C transmission. These problems have been exacerbated in recent years by the use of crystal methamphetamine (commonly called crystal meth), particularly in BC. Methamphetamine use is becoming increasingly common among marginalized youth, particularly those whose social and economic environment is the street. It is estimated there are between 45,000 to 150,000 street-involved youth in Canada, most of whom live in the large urban centres of Toronto, Montreal and Vancouver. Illicit drug use and unsafe sexual practices, including unprotected sex and sex trade work, increase susceptibility to HIV infection among street-involved youth. Brandon Marshall is one of the few researchers investigating the relationship between illicit drug use and sexual risk behaviours among street-involved youth. Using data collected from the B.C. Centre for Excellence in HIV/AIDS At-Risk Youth Study, he will examine how different social, structural, and environmental factors impact sexual practices. Specific factors include the age of first sexual experience, sexual orientation, illicit drug use, sexual relationships with older partners, access to health services, and involvement in the Downtown Eastside community of Vancouver, where drug use and poverty are prominent. This research will improve our understanding of illicit drug use and sexual activity in marginalized youth and will play an important role in developing sexual health education and prevention programs for youth at-risk.
Characterization of a kinase implicated in kinetochore function during S phase
Chromosomes, which are a compacted form of DNA, must be accurately duplicated and separated into two new daughter cells during each cell cycle. Genetic instability arises when chromosomes are separated improperly. This error is the source of many diseases, such as cancer and Downâs syndrome. Accurate chromosome separation relies on machinery assembled on each chromosome called the kinetochore. The regulation of the kinteochore is essential for cellular fitness and prevention of genetic instability. Understanding the mechanism by which the kinetochore is regulated will lead to a better view of cellular division and will provide insight into the treatment of diseases such as cancer. Because chromosome separation is a fundamental cellular process in all types of cells, Jennifer McQueen is using budding yeast as a model to study chromosome segregation. She is using many genetic and biochemical tools to examine the involvement of the Mck1 kinase in chromosome separation. Her project aims to discover a new role for the Mck1 kinase in kinetochore function and to produce a new model of kinteochore regulation that is applicable to human health.
The biological role of bone marrow-derived keratinocyte precursor cells in wound healing
Skin, which is the most extensive organ in the human body, performs multiple vital functions. Wounds to this organ, whether chronic or acute, are a serious threat because they leave the body open to infection. Thatâs why burns are a major cause of infection-associated deaths and why early replacement of burned tissues is so critically important. There is an urgent need to engineer skin substitutes for patients with extensive burns who do not have enough skin available for harvesting as grafts to close wounds. However, relatively little is known about how to establish a large-scale production of skin substitutes and how to control the healing process when such material is used. Bone marrow-derived stem cells may be a potential source for the preparation of skin substitutes due to their capacity to be reprogrammed to produce a variety of cell types. Abelardo Medina is studying whether bone marrow-derived stem cells can be used in this fashion both to close wounds and to improve wound healing. Findings from his research may also lead to a better understanding of the healing process and the treatment of chronic non-healing ulcers that develop in elderly people, diabetic and immuno-compromised patients. It also may contribute to a better understanding of the processes associated with over-healing wounds such as those that result in thick burn scars.
Use of a recombinant fusion protein to expand hematopoietic stem cells in vitro and to elucidate mechanisms that determine the expansion and self-renewal potential of mouse fetal liver and adult stem âŠ
Bone marrow is the tissue that fills most bone cavities and is the source of red blood cells and many white blood cells. Disorders that require bone marrow transplantation include aplastic anemia (inadequate blood cell formation by bone marrow), immune disorders, and many types of blood cancers. Current bone marrow transplantation therapies are limited by the number of blood-forming hematopoietic stem cells (HSC) that can be isolated from the patient or donor and transplanted to the patient. Typically, bone marrow or peripheral blood, as closely matched as possible to the patient, is transplanted into the patient. As this match is rarely perfect, patients will often develop a condition of varying severity known as graft-versus-host disease, which causes the patientâs immune system to destroy donor cells. Michelle Miller aims to generate in the laboratory a non-viral method of expanding HSC in the aim of avoiding certain complications that can arise from gene therapy or allogenic bone marrow transplantation.. Michelle (or Ms. Miller) is in the process of testing a fusion protein, which in viral form, has proven to lead to significant HSC expansion and generation of functional mature cells without leading to malignancy. She is also investigating whether there are pathways in common between the self-renewal capacity of mouse fetal liver HSC and those found in the adult as these cells perform better in transplantation tests when compared to HSC from adults. Ms. Miller (or Michelle â see above)hopes her research will lead to increased knowledge about hematopoietic stem cells, and to safer, more effective stem cell therapies.
Impact of community engaged arts on the health status of older adults
With the number of seniors in Canadaâs population increasing, more older adults are potentially dealing with chronic or recurring health issues. Given this trend, thereâs an essential need to identify health resources available to these individuals and to evaluate the effectiveness of these resources in impacting health status. Recent research has show that that creative involvement in the arts positively impacts the health of older adults. Elaine Moody is investigating how a community-based art project impacts health among its older adult participants. She is studying groups of seniors in the Vancouver area who are currently participating in community-engaged arts projects focused on developing creative and artistic abilities, and providing opportunities to meaningfully contribute to their communities. Through a questionnaire and a series of interviews, Elaine is collecting information about the health status of the participants, including physical, mental and social health, and overall well-being. Using statistical methods, she is examining the information obtained to determine if health status has improved over the course of the study. Her overall aim is to provide a clearer understanding of the health benefits of participating in community engaged arts for older adults.
Modulation of Cav3.2 T-type calcium channels through neuronal nitric oxide synthase activity
Normal brain activity involves the controlled transmission of electrical impulses across networks of neurons (nerve cells). Occasionally, undesired electrical activity occurs within cellular networks and a response is necessary to suppress this outburst. Kirk Mulatz is investigating a negative feedback mechanism that allows neurons to inhibit this atypical electrical activity. He is focusing on the role of T-type calcium ion channels in generating this aberrant electrical activity, and exploring the effectiveness of inhibiting characteristics of the channels to inhibit the activity. Investigations into negative feedback mechanisms both increase understanding of normal brain activity and how cells respond to abnormal activity. A number of neuronal disorders such as epilepsies, mood disorders and chronic pain are associated with atypical brain activity, and the feedback mechanism that Mulatz is researching may contribute to restoring normal activity across cellular networks.
Dimensionality and implications of reduced cognitive performance following kidney transplant
Chronic kidney disease (CKD) is an increasingly common disorder among middle-aged and older adults. More than 1,000 Canadians received kidney transplants in 1999, and there were more than three times that many on waiting lists. Deficits in memory and cognition are common in adults with chronic kidney disease and these worsen with increasing age. Cognitive abilities continue to be impaired following successful kidney transplant. However, decreased cognitive function in successful kidney transplant patients, which has vast implications on quality of life, has not been thoroughly examined. Theone Paterson is studying the everyday cognitive ability of renal transplant patients and how age, traditional and everyday measures of cognitive performance, and differing emotional states affect their quality of life and their ability to function in society on a daily basis post transplant. Specifically, Patersonâs research is looking at how these factors affect their ability to follow treatment regimens, such as taking medicines and following dietary restrictions. This work could lead to new approaches, including special training for healthcare providers in ways of supporting patients to better understand and remember aspects of treatment. Ultimately, the goal is to improve patientsâ lives.
The effect of intermittent hypoxic and hypercapnic protocols on cerebral blood flow regulation at rest and exercise
Sleep apnea causes involuntary stops in breathing during sleep, up to 400 times a night. About 24 per cent of men and 9 per cent of women experience sleep apnea symptoms. People with this condition are at greater risk for stroke. Normally, we take in oxygen when we inhale and expel carbon dioxide when we exhale. During an apnea episode, breathing temporarily stops, so oxygen is not taken in and carbon dioxide accumulates. When this occurs, blood vessels in the brain expand due to an increase of carbon dioxide in the brain, which leads to an improvement in blood flow reducing the chance of brain damage from insufficient oxygen. However, this mechanism becomes less sensitive with a repeated lack of oxygen or exposure to higher than normal levels of carbon dioxide. Jordan Querido is investigating the combined effect of low oxygen and high carbon dioxide to determine which plays a greater role in decreasing the expansion of blood vessels and increasing the risk of stroke. Querido will also examine whether these repetitive exposures lessen the blood vesselsâ ability to dilate during exercise, when extra oxygen is needed. An exercise program is often prescribed for sleep apnea patients, as most are overweight. This research will help to clarify whether patients are at greater risk of stroke during exercise, with the goal of designing safe exercise rehabilitation programs for sleep apnea patients.
Autism Spectrum Disorders: Identification of Novel Microdeletion and Microduplication Syndromes and Clinical Endophenotypes
Autism spectrum disorders (ASDs) affect more than one in 250 people and are characterized by significant impairments in social interactions and communication as well as inappropriately focused behaviours and restricted interests. Research involving sibling, twin and family studies has revealed the predominant role of genetic factors in ASDs and also identified regions in chromosomes where genes conveying susceptibility to ASDs might be located. Furthermore, recent studies have shown that chromosome anomalies can be found in five to 28 per cent of persons with ASDs, depending on whether they have cognitive delay and/or physical anomalies. Noemie Riendeau is exploring the genomic changes and molecular genetics underlying ASDs, as well as their clinical presentation and associated genomic syndromes. She is using a genome screening method known as Comparative Genomic Hybridization (array-CGH) to detect small chromosomal imbalances called microdeletions and microduplications in people with autism. The hope is that identifying these imbalances will help pinpoint genomic regions where genes associated with Autism Spectrum Disorders (ASDs) are located. The research also investigates how these genomic changes correlate with the clinical phenotypes of the patients, especially those with dysmorphic features and/or intellectual disability, but also for those cases described as simple autism. By defining new microdeletion and microduplication syndromes, this research will contribute to a better understanding of the genetic basis of ASDs and potentially to improved methods for early detection and treatment.