Most language processing occurs in the left hemisphere of the brain. In schizophrenia, language is disturbed on several levels: from abnormal anatomy in essential regions of the left hemisphere to deficits in comprehension and expression. Studies suggest genetic and environmental factors interact to cause abnormal anatomical development in the left hemisphere, resulting in abnormal functions that lead to schizophrenia symptoms. Sara Weinstein is investigating how abnormal brain structure and brain functions relate to a deviation in linguistic processing and expression that results in thought disorder, which is a primary symptom of schizophrenia. The research could help explain what causes schizophrenia symptoms — the first step toward developing more effective treatments.
Every year more than 20,000 Canadians with advanced osteoarthritis receive hip replacements. A new surgical technique resurfaces the head of the femur (the long thigh bone between the hip and knee) with a metal cap, removing far less bone than the traditional method, which involves removing a large portion of the upper femur. Hip replacements for active patients under the age of 55 have significantly increased and many of these patients will likely outlive their first hip implants. This new technique will help ensure they have enough bone to support a second surgery. Surgeons use a cumbersome alignment guide to insert a wire in the top of the femur and position the implant, which leads to variations in alignment that can loosen the implant or cause the femur to fracture. Jill Brimacombe is designing a computer-assisted surgical technique to help surgeons position the implants more accurately. The computer-assisted tool could reduce surgery time, be easier for surgeons to use, and improve accuracy, which would lengthen the life span of patients’ implants.
Organisms that cause disease use various strategies to create infection. Bacteria such as Mycobacterium tuberculosis invade cells in the human immune system. These bacteria manipulate the internal machinery of a host cell to enter and survive inside the cell. A cell contains many different types of molecules that interact in complex ways to control cell behaviours. Michael Hsing is studying these interactions to understand how bacterial invasions occur. He is using a computer method, called the semantic network, to simulate molecular interactions and cellular behaviours during bacterial invasions. The research could enable researchers to predict how cells respond in different situations, potentially leading to development of drugs to prevent and treat bacterial infections.
Melanoma is an aggressive and lethal form of skin cancer that is increasingly prevalent among Caucasians. Although often curable if diagnosed early and surgically removed, melanoma tumors can rapidly metastasize (spread) to other parts of the body. Patients diagnosed with melanoma at later stages face a poor prognosis and survival rates averaging only six to ten months. Once it has spread, melanoma is extremely difficult to treat because it does not respond well to conventional cancer treatments such as radiation and chemotherapy. But the reason for this resistance is unknown. Most anti-cancer drugs induce apoptosis (programmed cell death) in tumor cells. Melanoma may have abnormally high levels of cell survival genes, making them difficult to kill with such drugs. Alison Karst is investigating whether introduction of the PUMA cell death gene into malignant tumors could overcome this problem and sensitize malignant cells to chemotherapy.
Each year in Canada more than 24,000 people will fracture hips due to weakened bones caused by osteoporosis. Current ability to predict risk of hip fracture is limited. Dual-energy x-ray absorptiometry (DXA) is used to assess bone density, but it shows a two-dimensional representation of bone, which is a three-dimensional structure. DXA is also unable to assess the structural properties of bone, which are a major factor in bone strength. Sarah Manske is evaluating whether two emerging technologies can accurately measure bone structure and strength. Magnetic Resonance Imaging (MRI) can measure cross-sections of bones to evaluate strength, without radiation exposure. Quantitative computed tomography (QCT) can assess bone in three dimensions. Sarah aims to develop a model integrating different imaging technologies to provide a more comprehensive picture of fracture risk. The information could be used to target preventative health strategies to help those at greatest risk of hip fracture.
A growing body of evidence indicates that a lack of control over working conditions contributes significantly to poor health and that social networks have a positive impact on health. Amber Louie is building on that research by analyzing the impact of organizational restructuring and changing work conditions on health care workers. Amber is examining the barriers to workers’ control in the health care sector, and the factors that facilitate or serve as incentives for workers’ control. She is also investigating the relative effectiveness of the various forms that workers’ control may take. The research involves interviewing community health workers to assess individual perceptions about social support, participation in decision-making and other factors that affect their working conditions. The study could provide important information for health care practitioners, human resource managers and community developers to use in the design, implementation and evaluation of workplace and community health promotion programs.
Tissues in multi-cellular organisms maintain a state of equilibrium (homeostasis) through a delicate balance between controlled cell growth and programmed cell death (apoptosis). Programmed cell death is required to remove superfluous, damaged or harmful cells. Uncontrolled cell growth can lead to cancer, autoimmune disorders and neurodegenerative diseases. The BCL-2 family of proteins tightly regulates the cell death process. Dr. Marc Germain is investigating their role in cell death. One of these proteins, Mcl-1, prevents cell death and also seems to have a role in controlling cell division. Dr. Germain is examining how different forms of this protein control the body’s equilibrium, which could improve understanding of how cancer develops and potentially lead to new anti-cancer drugs.
Prostate cancer is the second leading cause of cancer death in men. While curable if discovered early, many men are diagnosed after the disease has metastasized (spread) to other parts of the body. At this point few treatments are effective. Androgens (male sex hormones) regulate prostate growth and development. Removing androgens is the most effective treatment for advanced prostate cancer. However, some cancer cells eventually adapt and become androgen-independent, enabling the disease to progress. The YB-1 protein regulates two genes involved in the progression of androgen independence. Using sophisticated DNA microarray technology, Dr. Susan Moore aims to identify additional genes regulated by this protein to learn how androgen independence develops. The findings could lead to earlier diagnosis and new treatments for prostate cancer.
Superantigens are secreted toxins from some kinds of bacteria that stimulate a massive and damaging immune response in the body, causing a number of diseases. For example, TSST-1 is a superantigen that can cause toxic shock syndrome which may lead to multiple organ failure and often death. Shirin Kalyan is studying how the immune system responds to superantigens at the cellular level. Superantigens activate between 5 to 30 percent of all T cells (white blood cells involved in fighting infection). This ability to stimulate such a large pool of immune cells leads to a massive inflammatory response. In contrast, conventional antigens activate less than .01 per cent of T cells. Shirin is investigating whether a particular type of primodial innate T cell can influence the immune response that causes toxic shock syndrome. The findings could lead to more effective treatments for toxic shock syndrome and other immune disorders caused by superantigens.
Physical activities involving repetitive strain can injure tendons, causing chronic pain and disability. Contrary to previous thinking, chronic overuse tendon injuries do not involve inflammation. Instead, these injuries primarily involve the breakdown and disarray of collagen, a structural protein that is the primary support for tendons as well as bone, cartilage and skin. Recent research associates chronic tendon injury with excessive apoptosis (programmed cell death) among tendon cells. Alexander Scott’s preliminary laboratory studies identified two stressful conditions that can cause the problem: repetitive mechanical strain and lack of oxygen. Now he is investigating the basic mechanisms of tendon degeneration, with the aim of discovering whether abnormal rates of cell death occur in real life models of tendon injury. Alexander is also testing whether IGF-1, a potent growth factor, can help tendons better recover from injury. The research could lead to new treatments for people who suffer from painful tendon injuries.