Time filter

Source Type

PubMed | Hotchkiss Brain Institute and
Type: Journal Article | Journal: The Journal of neuroscience : the official journal of the Society for Neuroscience | Year: 2016

Mossy fiber afferents to cerebellar granule cells form the primary synaptic relay into cerebellum, providing an ideal site to process signal inputs differentially. Mossy fiber input is known to exhibit a long-term potentiation (LTP) of synaptic efficacy through a combination of presynaptic and postsynaptic mechanisms. However, the specific postsynaptic mechanisms contributing to LTP of mossy fiber input is unknown. The current study tested the hypothesis that LTP induces a change in intrinsic membrane excitability of rat cerebellar granule cells through modification of Kv4 A-type potassium channels. We found that theta-burst stimulation of mossy fiber input in lobule 9 granule cells lowered the current threshold to spike and increases the gain of spike firing by 2- to 3-fold. The change in postsynaptic excitability was traced to hyperpolarizing shifts in both the half-inactivation and half-activation potentials of Kv4 that occurred upon coactivating NMDAR and group I metabotropic glutamatergic receptors. The effects of theta-burst stimulation on Kv4 channel control of the gain of spike firing depended on a signaling cascade leading to extracellular signal-related kinase activation. Under physiological conditions, LTP of synaptically evoked spike output was expressed preferentially for short bursts characteristic of sensory input, helping to shape signal processing at the mossy fiber-granule cell relay.Cerebellar granule cells receive mossy fiber inputs that convey information on different sensory modalities and feedback from descending cortical projections. Recent work suggests that signal processing across multiple cerebellar lobules is controlled differentially by postsynaptic ionic mechanisms at the level of granule cells. We found that long-term potentiation (LTP) of mossy fiber input invoked a large increase in granule cell excitability by modifying the biophysical properties of Kv4 channels through a specific signaling cascade. LTP of granule cell output became evident in response to bursts of mossy fiber input, revealing that Kv4 control of intrinsic excitability is modified to respond most effectively to patterns of afferent input that are characteristic of physiological sensory patterns.


News Article | February 22, 2017
Site: www.eurekalert.org

New study highlights the need for heightened prevention and management of depression in psoriasis patients, reports the Journal of Investigative Dermatology Philadelphia, PA, February 22, 2017 - Psoriasis is a lifelong disease that is associated with significant cosmetic and physical disability and puts patients at increased risk for many major medical disorders. A multidisciplinary team of researchers at the University of Calgary, Canada, have found that psoriasis patients who developed depression were at a 37% greater risk of subsequently developing psoriatic arthritis, compared with psoriasis patients who did not develop depression. Their findings are published in the Journal of Investigative Dermatology. Psoriasis is a long-lasting inflammatory skin disease characterized by red, itchy, and scaly patches of skin. Approximately 8.5% of psoriasis patients have psoriatic arthritis, which is characterized by psoriasis plus inflammation of and around the joints. "For many years, the rheumatology and dermatology communities have been trying to understand which patients with psoriasis go on to develop psoriatic arthritis and how we might detect it earlier in the disease course," explained senior investigator Cheryl Barnabe, MD, MSc, of the McCaig Institute for Bone and Joint Health and the O'Brien Institute for Public Health, Cumming School of Medicine, at the University of Calgary, Alberta, Canada. Depression is common among patients with psoriasis. Based on recent laboratory work demonstrating that major depressive disorder is associated with increased systemic inflammation, the team of researchers hypothesized that psoriasis patients who develop depression are at increased risk of subsequently developing psoriatic arthritis. Investigators used The Health Improvement Network (THIN), a primary care medical records database in the United Kingdom, to identify over 70,000 patients with a new diagnosis of psoriasis. Through follow-up records, they identified individuals who subsequently developed depression and those who developed psoriatic arthritis. Patients were followed for up to 25 years or until they developed psoriatic arthritis. Statistical analysis showed that patients with psoriasis who developed major depressive disorder were at 37% greater risk of subsequently developing psoriatic arthritis compared with patients who did not develop depression, even after accounting for numerous other factors such as age and use of alcohol. The study highlights the need for physicians to manage patients with psoriasis to identify and address depression. This could include rapid, effective treatment of psoriasis and psychosocial management of the cosmetic burden of psoriasis. The study also draws into question the biological mechanisms by which depression increases the risk for developing psoriatic arthritis. These mechanisms may include altered systemic inflammation as a consequence of depression, or even the role of lifestyle behaviors such as physical activity or nutrition, which are typically worsened by depression, and which may place an individual at risk for psoriatic arthritis. "There is a tendency to think of depression as a purely 'psychological' or 'emotional' issue, but it also has physical effects and changes in inflammatory and immune markers have been reported in depressed people," commented Scott Patten, MD, PhD, the O'Brien Institute for Public Health, Hotchkiss Brain Institute and Mathison Centre for Mental Health Research and Education, Cumming School of Medicine. "Depression may be a risk factor for a variety of chronic conditions and this research is an example of how big data approaches can identify these associations." Laurie Parsons, MD, of the Cumming School of Medicine, added: "It is evident to physicians who treat patients with psoriasis, that there is a significant psychological and social burden associated with this disease, which is reflected in an increase in the rates of depression. This study brings us a little closer to understanding the role of chronic inflammation as a systemic player in both the physical and psychological manifestations of psoriasis and underscores the need for closer attention to symptoms of depression in this group of patients." "This study raises important questions on the role of systemic inflammation, which is also elevated in depression, in driving a disease phenotype, which needs to be confirmed in clinical cohorts," concluded Dr Barnabe.


News Article | October 26, 2016
Site: www.eurekalert.org

Brain functions are controlled by millions of brain cells. However, in order to understand how the brain controls functions, such as simple reflexes or learning and memory, we must be able to record the activity of large networks and groups of neurons. Conventional methods have allowed scientists to record the activity of neurons for minutes, but a new technology, developed by University of Calgary researchers, known as a bionic hybrid neuro chip, is able to record activity in animal brain cells for weeks at a much higher resolution. The technological advancement was published in the journal Scientific Reports this month. "These chips are 15 times more sensitive than conventional neuro chips," says Naweed Syed, PhD, scientific director of the University of Calgary, Cumming School of Medicine's Alberta Children's Hospital Research Institute, member of the Hotchkiss Brain Institute and senior author on the study. "This allows brain cell signals to be amplified more easily and to see real time recordings of brain cell activity at a resolution that has never been achieved before." The development of this technology will allow researchers to investigate and understand in greater depth, in animal models, the origins of neurological diseases and conditions such as epilepsy, as well as other cognitive functions such as learning and memory. "Recording this activity over a long period of time allows you to see changes that occur over time, in the activity itself," says Pierre Wijdenes, a PhD student in the Biomedical Engineering Graduate Program and the study's first author. "This helps to understand why certain neurons form connections with each other and why others won't." The cross-faculty team created the chip to mimic the natural biological contact between brain cells, essentially tricking the brain cells into believing that they are connecting with other brain cells. As a result, the cells immediately connect with the chip, thereby allowing researchers to view and record the two-way communication that would go on between two normal functioning brain cells. "We simulated what mother-nature does in nature and provided brain cells with an environment where they feel as if they are at home," says Syed. "This has allowed us to increase the sensitivity of our readings and help neurons build a long-term relationship with our electronic chip." While the chip is currently used to analyze animal brain cells, this increased resolution and the ability to make long-term recordings is bringing the technology one step closer to being effective in the recording of human brain cell activity. "Human brain cell signals are smaller and therefore require more sensitive electronic tools to be designed to pick up the signals," says Colin Dalton, Adjunct Professor in the Department of Electrical and Computer Engineering at the Schulich School of Engineering and a co-author on this study. Dalton is also the Facility Manager of the University of Calgary's Advanced Micro/nanosystems Integration Facility (AMIF), where the chips were designed and fabricated. Researchers hope the technology will one day be used as a tool to bring personalized therapeutic options to patients facing neurological disease. This discovery was funded by the Canadian Institutes of Health Research and the Natural Sciences and Engineering Research Council of Canada. The University of Calgary's multidisciplinary Engineering Solutions for Health: Biomedical Engineering research strategy is focused on developing solutions for pressing health challenges in disease and injury prevention, diagnosis and treatments. We are also applying systems engineering principles to continuously improve the health system.


News Article | November 10, 2016
Site: www.marketwired.com

CALGARY, AB--(Marketwired - November 10, 2016) - A new partnership between the Sheldon Kennedy Child Advocacy Centre (SKCAC) and the University of Calgary's Mathison Centre for Mental Health Research & Education will study the impact of child abuse on the developing brain. The goal is to use a scientific approach to understand which interventions work best to mitigate the impact of child abuse, to compare the impact of childhood sexual abuse to that of other forms of childhood trauma, and to understand why some children are more resilient than others. "I am so excited to see this collaboration between the SKCAC and the Mathison Centre to examine the impact of childhood abuse on the neurobiological and psychosocial development of young victims," says Sheldon Kennedy, Lead Director at the SKCAC. "For 20 years I've been working to help people really understand the impacts of child abuse; make the invisible visible. This research will help us do exactly that." As part of this study, children will receive an MRI scan of their brain to determine differences in structure and chemistry between participants who have experienced child abuse and those who have not. Researchers will also take saliva samples to analyze DNA, which could indicate epigenetic changes (changes in the genome caused by external factors) caused by environmental influences such as stress. Such epigenetic modifications of DNA structure caused by toxic stress could in turn lead to changes in brain structure, function and chemistry. "Despite emerging evidence that child abuse impacts the developing brain, the nature and extent of the effects are not well understood," says Dr. Paul Arnold, child psychiatrist and Director of the Mathison Centre at UCalgary's Cumming School of Medicine. "This study will impact care and provide a framework for personalized care informed by science." This first phase of the study is a two-year pilot study enrolling 240 children ages six to 17. Half of the study participants will be controls, and half will have experienced childhood abuse. The study will look at clinical and biological factors and how they relate to outcomes. After the initial pilot study, researchers hope to expand the study and enroll up to 1,000 children and follow them over a 10-15 year time period. The planned longitudinal study will be one of the most comprehensive studies of child abuse victims ever conducted. The SKCAC screens about 125 children for child abuse each month, with two-thirds of those cases related to sexual abuse. Childhood abuse increases the risk for mental health problems, including anxiety, depression, substance abuse and suicide. "Brain and mental health research partnerships with our community enable University of Calgary scientists to put knowledge into action and ultimately improve the lives of the children, youth and families we serve. We look forward to working closely with Sheldon and the Child Advocacy Centre on this vital new project," says Samuel Weiss, PhD, Director of the Hotchkiss Brain Institute and leader of the University of Calgary's Brain and Mental Health strategy. Led by the Hotchkiss Brain Institute (HBI), Brain and Mental Health is one of six strategic research themes guiding the University of Calgary towards its Eyes High goals. About the University of Calgary The University of Calgary is making tremendous progress on its journey to become one of Canada's top five research universities, where research and innovative teaching go hand in hand, and where we fully engage the communities we both serve and lead. This strategy is called Eyes High, inspired by the university's Gaelic motto, which translates as 'I will lift up my eyes.' For more information, visit ucalgary.ca. Stay up to date with University of Calgary news headlines on Twitter @UCalgary. For details on faculties and how to reach experts go to our media centre at ucalgary.ca/news/media. About the Cumming School of Medicine The University of Calgary's Cumming School of Medicine is a leader in health research, with an international reputation for excellence and innovation in health care research and education. We train the next generation of health practitioners, and take new treatments and diagnostic techniques from the laboratory to the patient, always keeping in mind our goal: Creating the Future of Health. The medical school was created in 1967 and on June 17, 2014, was formally named the Cumming School of Medicine in recognition of Geoffrey Cumming's generous gift to the university. For more information, visit cumming.ucalgary.ca, or follow us on Twitter @UCalgaryMed. About The Mathison Centre for Mental Health Research & Education The Mathison Centre for Mental Health Research & Education supports research and education into the early identification, prevention and treatment of mental illness, with a special emphasis on youth populations. Created by the Hotchkiss Brain Institute and the Department of Psychiatry, The Mathison Centre partners with the Cumming School of Medicine and other faculties at the University of Calgary to inform mental health care strategies in our community and offer new hope to families in Calgary, throughout Alberta and the world. mathison.ucalgary.ca. The Sheldon Kennedy Child Advocacy Centre is transforming how the current system responds to child abuse by using a ground-breaking model of integration with six partnering agencies. Together, these agencies provide early-intervention, assessment, investigation and treatment to children, youth and families impacted by the most severe and complex cases of child abuse. The power of the Centre is unleashed through integrated services -- the right support at the right time -- that reduce the long-term impact of trauma and enable children, youth and families to recover to lead healthy, productive lives.


News Article | November 8, 2016
Site: www.marketwired.com

CALGARY, AB--(Marketwired - November 08, 2016) - A new partnership between the Sheldon Kennedy Child Advocacy Centre (SKCAC) and the University of Calgary's Mathison Centre for Mental Health Research & Education will study the impact of child abuse on the developing brain. The goal is to use a scientific approach to understand which interventions work best to mitigate the impact of child abuse, to compare the impact of childhood sexual abuse to that of other forms of childhood trauma, and to understand why some children are more resilient than others. WHAT: News conference followed by one-on-one interviews. WHEN: Thursday, November 10, 2016 at 11:15 a.m. Parking: Lot 53, adjacent to the Centre and facing the hand print. Parking payment is required. About the University of Calgary The University of Calgary is making tremendous progress on its journey to become one of Canada's top five research universities, where research and innovative teaching go hand in hand, and where we fully engage the communities we both serve and lead. This strategy is called Eyes High, inspired by the university's Gaelic motto, which translates as 'I will lift up my eyes.' For more information, visit ucalgary.ca. Stay up to date with University of Calgary news headlines on Twitter @UCalgary. For details on faculties and how to reach experts go to our media centre at ucalgary.ca/news/media. About the Cumming School of Medicine The University of Calgary's Cumming School of Medicine is a leader in health research, with an international reputation for excellence and innovation in health care research and education. We train the next generation of health practitioners, and take new treatments and diagnostic techniques from the laboratory to the patient, always keeping in mind our goal: Creating the Future of Health. The medical school was created in 1967 and on June 17, 2014, was formally named the Cumming School of Medicine in recognition of Geoffrey Cumming's generous gift to the university. For more information, visit cumming.ucalgary.ca, or follow us on Twitter @UCalgaryMed. About The Mathison Centre for Mental Health Research & Education The Mathison Centre for Mental Health Research & Education supports research and education into the early identification, prevention and treatment of mental illness, with a special emphasis on youth populations. Created by the Hotchkiss Brain Institute and the Department of Psychiatry, The Mathison Centre partners with the Cumming School of Medicine and other faculties at the University of Calgary to inform mental health care strategies in our community and offer new hope to families in Calgary, throughout Alberta and the world. mathison.ucalgary.ca.


News Article | November 10, 2016
Site: www.marketwired.com

CALGARY, AB--(Marketwired - November 10, 2016) - A new partnership between the Sheldon Kennedy Child Advocacy Centre (SKCAC) and the University of Calgary's Mathison Centre for Mental Health Research & Education will study the impact of child abuse on the developing brain. The goal is to use a scientific approach to understand which interventions work best to mitigate the impact of child abuse, to compare the impact of childhood sexual abuse to that of other forms of childhood trauma, and to understand why some children are more resilient than others. WHAT: News conference followed by one-on-one interviews. WHEN: Thursday, November 10, 2016 at 11:15 a.m. Parking: Lot 53, adjacent to the Centre and facing the hand print. Parking payment is required. About the University of Calgary The University of Calgary is making tremendous progress on its journey to become one of Canada's top five research universities, where research and innovative teaching go hand in hand, and where we fully engage the communities we both serve and lead. This strategy is called Eyes High, inspired by the university's Gaelic motto, which translates as 'I will lift up my eyes.' For more information, visit ucalgary.ca. Stay up to date with University of Calgary news headlines on Twitter @UCalgary. For details on faculties and how to reach experts go to our media centre at ucalgary.ca/news/media. About the Cumming School of Medicine The University of Calgary's Cumming School of Medicine is a leader in health research, with an international reputation for excellence and innovation in health care research and education. We train the next generation of health practitioners, and take new treatments and diagnostic techniques from the laboratory to the patient, always keeping in mind our goal: Creating the Future of Health. The medical school was created in 1967 and on June 17, 2014, was formally named the Cumming School of Medicine in recognition of Geoffrey Cumming's generous gift to the university. For more information, visit cumming.ucalgary.ca, or follow us on Twitter @UCalgaryMed. About The Mathison Centre for Mental Health Research & Education The Mathison Centre for Mental Health Research & Education supports research and education into the early identification, prevention and treatment of mental illness, with a special emphasis on youth populations. Created by the Hotchkiss Brain Institute and the Department of Psychiatry, The Mathison Centre partners with the Cumming School of Medicine and other faculties at the University of Calgary to inform mental health care strategies in our community and offer new hope to families in Calgary, throughout Alberta and the world. mathison.ucalgary.ca. About the Sheldon Kennedy Child Advocacy Centre The Sheldon Kennedy Child Advocacy Centre is transforming how the current system responds to child abuse by using a ground-breaking model of integration with six partnering agencies. Together, these agencies provide early-intervention, assessment, investigation and treatment to children, youth and families impacted by the most severe and complex cases of child abuse. The power of the Centre is unleashed through integrated services -- the right support at the right time -- that reduce the long-term impact of trauma and enable children, youth and families to recover to lead healthy, productive lives.

Loading Hotchkiss Brain Institute and collaborators
Loading Hotchkiss Brain Institute and collaborators