Thirty-second edition of the Vision Network Prize
Joelle Lavoie
Article: The Electroretinogram as a Biomarker of Central Dopamine and Serotonin: Potential Relevance to Psychiatric Disorders
Joëlle Lavoie studied in medical biology at the Université du Québec à Trois-Rivières. In 2008, she began a Master degree in neurobiology at Laval University supervised by Marc Hébert and Martin Beaulieu and she transferred to a Ph.D. in 2009. Her researches focus on the electroretinogram (ERG) as a biomarker of psychiatric disorders. She studies the origins of the ERG anomalies reported in patients with psychiatric disorders and she works with patients and animal models. Joëlle is granted by research fellowships from the Fonds de recherche du Québec – Santé (FRQS) and the Centre de recherche sur le cerveau, le comportement et la neuropsychiatrie (CRCN). She presented her work in several scientific events and international conferences where she received many awards and distinctions from the Association for Research in Vision and Ophthalmology (ARVO), the International Society for Clinical Electrophysiology of Vision (ISCEV) and the Vision Research Network. In her work published in the prestigious journal Biological Psychiatry, she demonstrates that alterations in central dopamine and serotonin neurotransmission can affect the ERG parameters. The ERG anomalies reported in psychiatric disorders might serve as biomarkers of central monoaminergic dysfunctions thus promoting the ERG measurements as a useful tool in psychiatric research.
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Joseph Bouskila
Article: Expression and localization of the cannabinoid receptor type 1 and the enzyme fatty acid amide hydrolase in the retina of vervet monkeys
Joseph Bouskila holds a bachelor degree in biomedical sciences and a master degree in visual sciences from University of Montreal. He is currently following a PhD degree in biomedical sciences in the laboratories of Drs. Maurice Ptito and Jean-François Bouchard. He is interested on the involvement of the endocannabinoid system in the monkey visual system. When he was an undergraduate student, he completed a fellowship in the laboratory of Dr. Christophe Faure. There, he learned various immunostaining techniques. His master thesis focused on the detection of key proteins of the monkey retinal endocannabinoid system; with his thesis entitled “Expression and localization of the endocannabinoid system in the retina of the monkey”. The aim of his doctoral thesis is to characterize the endocannabinoid signaling system in the central nervous system (CNS) with an emphasis on all visual structures, including the retina, lateral geniculate nucleus and primary visual cortex. For millennia, cannabis has been a drug of abuse that played a significant role in human history. The CB1 receptor is largely responsible for mediating the effects of cannabinoid binding in the brain and is one of the most widely highly expressed G protein coupled receptor throughout the CNS. It is involved in many brain functions such as learning, memory, and motor coordination. However, its role on vision and during visual system development is still unknown.
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Kanawarpal Singh
Article: Pulsatile Movement of the Optic Nerve Head and the Peripapillary Retina in Normal Subjects and in Glaucoma
Mr. Singh holds a master degree in Laser science and applications from Devi Ahilya University,
Indore (India). During his master degree he became familiar with the world of lasers and its use
in biological sciences. He worked as an exchange student at ophthalmology department of
Hôpital Maisonneuve-Rosemont for one year as a part of his master degree. The fascinating
world of vision motivated him to pursue his PhD program in this field.
To pursue his work, he received PhD scholarships from “Le Fonds québécois de la recherche sur
la nature et les technologies” (2008-2009) and “Le Fonds de la recherche en santé du Québec”
(2009-2012). He received the prestigious Innovation Challenge Award (2012) form Natural
Sciences and Engineering Research Council of Canada (NSERC) for his contribution in the
development of a machine for early diagnosis of glaucoma. He also received Incubic/Milton-
Chang travel grant to present his work at Conference on Laser and Electro Optics. He won a
travel grant from Ministère de l'Éducation, du Loisir et du Sport in 2009 to visit medical
university of Vienna, Austria in order to perform experiments related to his work.
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Trente et unième concours du prix réseau vision
Marie-Ève Laramée
Article:Principal Component and Cluster Analysis of Layer V Pyramidal Cells in Visual and Non-
Visual Cortical Areas Projecting to the Primary Visual Cortex of the Mouse.
Marie-Eve Laramée studied in medical biology at the Université du Québec à Trois-Rivières. By the
end of her second year, Dr Denis Boire hired her as a research assistant in his lab. Already interested by neuroscience researches, she rapidly discovered her passion in neuroanatomy and decided to pursue her PhD studying the organization of corticocortical connections and their reorganisation in blind mice. In 2008, the FRSQ Vision Research Network granted her with a support recruitment fellowship and financed her internship in Dr Kathleen Rockland's laboratory at RIKEN (Japan). She afterwards participated in many scientific meetings where she presented her work and received numerous prizes. In 2009, she obtained the prestigeous NSERC Alexander-Graham Bell fellowship, which allowed her to pursue her thesis and, with the Michael Smith foreign study supplement, to go in Dr Lutgarde Arkens' laboratory at the catholic University of Louvain (Belgium). In her second paper, presented here, Marie-Eve studied the connections from the secondary visual areas, the primary auditory and the primary somatosensory cortices towards the primary visual cortex. The results yielded a high morphological heterogeneity within the population of layer V pyramidal neurons involved in this connection and showed that these morpohlogies could be found in all areas.
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Thirtieth Edition of the Vision Network Prize
Jean-Sébastien Joyal
Article:Ischemic neurons prevent vascular regeneration of neural tissue by secreting semaphorin 3A
Dr. Jean-Sébastien Joyal is a pediatric intensive care physician and a Ph.D. in pharmacology. After completing his international baccalaureate at Lester B. Pearson United World College in British Colombia, he obtained his medical degree from McGill University in 2000. He trained in pediatrics and sub-specialized in pediatric intensive care at Sainte-Justine Hospital. While completing his clinical training, Dr. Joyal pursued a Ph.D. in pharmacology at McGill University under the supervision of Dr. Sylvain Chemtob. He was the recipient of prestigious scholarships from the Hemostasis Research Fellowship and the Canadian Child Health Clinician-Scientist Program, a CIHR training initiative. Dr. Joyal completed his clinical training in pediatric cardiac intensive care at Great Ormond Street Hospital, London in 2010. He joined Dr. Lois Smith’s lab at Harvard Medical School for postdoctoral training in 2011. His recent work published in the journal Blood (cover article) explores the neurovascular interactions contributing to retinal angiogenesis in a model of proliferative retinopathy.
Nicholas Sitaras
Article:Ischemic neurons prevent vascular regeneration of neural tissue by secreting semaphorin 3A
Nicholas Sitaras completed his bachelors degree with Honour’s in Biochemistry at Concordia University and enrolled in a Master’s program in Pharmacology at Université de Montréal in 2009 under the mentorship of Dr. Sylvain Chemtob. Nicholas completed his fast‐track to PhD under the co‐supervision of Dr. Chemtob and Dr. Mike Sapieha. His work published in Blood (cover article) unravels the dynamics behind vascular repulsion involving neuronal‐derived guidance cue Semaphorin3A and its impact in proliferative retinopathies. Nicholas is the recipient of several scholarships including the prestigious Frederick Banting and Charles Best CIHR Masters Awards. He received support from CHU Sainte‐Justine–Foundation of Stars, the Masters‐to‐PhD Fast‐Track Award from the Faculté d’étude superieure et postdoctorale (FESP) and a Doctorate Award from the Fondsde la recherche en santé du Québec (FRSQ). Nichol as is presently conducting research toward the completion of his PhD at Université de Montréal in the Department of Pharmacology and Ophthalmology at Maisonneuve‐Rosemont Hospital. The investigations delve into the pharmacology of certain peptide agonists in the retina, looking specifically in their function in p roliferative retinopathies.
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Twenty ninth Edition of the Vision Network Prize
Valentina Vucea
Article:Blood oxygenation measurements by multichannel reflectometry on the venous and arterial structures of the retina
Holder of a Master’s degree in Physics from the University of Craiova, in Romania, I arrived in Quebec in 2002 in order to advance my studies at the University of Montreal. Here, I became acquainted with Professor Vasile Diaconu and began my master’s degree in 2004 in his laboratory at the School of Optometry. It’s during my Masters that I got interested in the methodology behind blood oxygenation determination from measurements taken from the eye with a spectroreflectometer. I continued working actively in this domain during my doctorate in biomedical engineering, under the supervision of Dr. Diaconu, Professor at the Institut de de Génie Biomédical de l’Université de Montréal. Along with my background and the expertise of my research advisor, I unified physics and ophthalmology in my
doctoral thesis by the use of the spectroreflectometer, a continuous non-invasive method that measures blood oxygenation. During my Master’s and Doctorate, I obtained excellence grants from the School of Optometry, and the Faculty of Medicine de l’Université de Montréal and also, a doctoral research bursary from FQRNT (Fonds québécois de la recherche sur la nature et les technologies), for two consecutive years. In 2009, I won the excellence award for my oral presentation during the 15th annual reunion of the “réseau FRSQ de recherche en santé de la vision”, and in 2010, the excellence award for my poster presentation during the « Journée scientifique du Groupe de Recherche en Sciences de la Vision ». Also, I am the author of twenty institutional, national and international presentations and two publications, of which one recently appeared in the very prestigious revue “Applied Optics”.
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Twenty eighth Edition of the Vision Network Prize
Allison Dorfman
Article: Immunohistochemical evidence of synaptic retraction, cytoarchitectural remodelling and cell death in the inner retina of the rat model of OIR.
Following the completion of the B.Sc. program at McGill University with a major in Physiology and a minor in Pharmacology and Therapeutics in 2000, I entered the PhD graduate program in Pharmacology and Therapeutics under the co-supervision of Drs. Chemtob and Lachapelle. My research is focused on a model of retinopathy of prematurity (ROP) which is a disease that affects prematurely born infants that can ultimately lead to blindness. Oxygen-induced retinopathy (OIR) in the neonatal rat provides a model for ROP and other diseases that are characterized by abnormal retinal angiogenesis. In order to better understand the pathophysiology of this retinopathy, I have carried out electrophysiological (flash ERGs and VEPs, multifocal ERGs), histological, immunohistochemical and vascular studies in both albino and pigmented rat strains following exposure to hyperoxic conditions. The results from my first study showed that trolox C, a water soluble analogue of vitamin E, is able to at least partly prevent retinal functional and structural damage as evaluated with the ERG and histology, respectively, when administered throughout the hyperoxic phase. These results suggest a role for free radicals among other factors in creating the pathogenesis of OIR. Our findings with Trolox C led to the current study comparing the pigmented Long Evans and albino Sprague Dawley rat models of OIR in order to determine whether melanin, also known to act as an antioxidant, plays a role in protecting the retina from oxygen toxicity. In humans, studies that compared the racial incidence of retinopathy of prematurity (ROP) suggested that ocular pigmentation might offer protection against the development of severe ROP. The severity of the OIR was determined by examining retinal flatmounts (retinal vasculature assessment), protein level quantification and cellular localization of fibroblast growth factor (FGF)-2 and ciliary neurotrophic factor (CNTF; Western blot analysis and immunohistochemistry, respectively), retinal histology, and photopic and scotopic electroretinograms (ERGs). Surprisingly, irrespective of the parameter considered, vascular, structural and functional deficits resulting from postnatal hyperoxia were significantly more pronounced in pigmented Long Evans rats compared to albino Sprague Dawley rats. Our current study is focused on using various immunohistochemical techniques (anti-synaptophysin, anti-PKC, anti-recoverin, anti-mGluR6, anti-bassoon and anti-calbindin) in order to further elucidate the mechanism by which synaptic retraction occurs. Results suggest that cell death and synaptic retraction are at the root of OPL thinning and increased TUNEL positive cells in the INL confirm that cells die, at least in part, due to apoptosis. Our findings propose a previously undescribed mechanism of cell death and synaptic retraction that are likely at the origin of the functional consequences of hyperoxia. In conjunction with my graduate studies, I worked at the Montreal Children’s Hospital ERG clinic from 2002-2008 (department of Ophthalmology) where I saw patients with diseases such as retinitis pigmentosa, congenital stationary night blindness and age related macular degeneration, among others. The results from both my laboratory and clinical work have been presented at a number of international and local conferences. From 1999-2000, I was given the opportunity to pursue a research project for completion of the minor program in Pharmacology and Therapeutics under the supervision of Drs. De Koninck and Ribeiro-Da-Silva. This work was focused on the characterization of cells in Lamina I of the spinal dorsal horn, an area involved in the relay of nociceptive and thermoreceptive information. This project, as well as my earliest research experience (1996-1998) at the Jewish General Hospital (supervised by Drs. Mitmaker and Black), involved the generation and organization of data from colon, head and neck cancer patients, were all instrumental in helping me realize my passion for research and my eagerness to pursue a doctoral degree.
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Twenty seventh Edition of the Vision Network Prize
Olivier Collignon
Article: Functional specialization for auditory–spatial processing in the occipital cortex of congenitally blind humans
Olivier Collignon earned his degree in clinical psychology at the University of Liege (Belgium) in 2001. He then completed a master's degree in experimental psychology and a doctorate in neuroscience at the catholic University of Louvain (Belgium). It was during his PhD that he started studying the phenomena of brain plasticity in the blind person. He continued to work actively in this issue during the post-doctoral researches he has done under the supervision of Prof. Franco Lepore at the Centre for Research in Neuropsychology and Cognition (CERNEC) of the Department of Psychology at the University of Montreal. The objective of these researches is to investigate whether the occipital cortex of blind people maintains functional properties comparable to those observed in the sighted person. In recent work using functional magnetic resonance imaging (fMRI), he was able to demonstrate that the dorsal occipital regions, normally regarded as visuospatial in the sighted person, maintain a preference for the processing of auditory spatial informations in peoples blind from birth.
Olivier is currently enrolled in a second postdoc at the Research Center of the CHU Sainte-Justine, during which he is interested in the development of multisensory processing in children and in autistic persons.
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Twenty sixth Edition of the Vision Network Prize
Caroline Jacques
Article: Long-Term Effects of Prenatal Omega-3 Fatty Acid Intake on Visual Function in School-Age Children
After having obtained a Master degree in Clinical Psychology from the University of Liege in Belgium, Caroline Jacques came to Quebec in 2006 with the aim of studying nutrition at the University of Montreal. There she met Dr. Dave Saint-Amour, director of the laboratory of visual electrophysiology at CHU Sainte-Justine and professor at the department of psychology at the University from Quebec in Montreal since April 2010. Dr. Dave Saint-Amour became her research director in collaboration with Dr. Emile Levy, full-time
professor at the Department of Nutrition at the University of Montreal and director of the Gastroenterology, Hepatology and Nutrition Unit at the CHU Sainte-Justine. With the help of both professors and thanks to their expertise and advice, Caroline could link Neuropsychology and Nutrition in her Master’s thesis about the effect of omega-3 fatty acids on visual functions. She received a Master degree in Nutrition in April 2010 and
afterwards she continued to work with Dr. Saint-Amour further to winning the first place for a scholarship granted by FQRNT (Fonds québécois de la recherche sur la nature et les technologies) to outstanding foreign students. During her studies in Nutrition, Caroline also won each year a scholarship from the nutrition department and another from the “Fondation
de l’Hôpital Sainte-Justine”. In 2009, she won several awards including two excellence awards for poster presentations: one at the 47th ISCEV International Congress and the second one at the 15th “Réseau FRSQ de Recherche en Santé de la Vision” Annual Meeting. The same year, she obtained as well an award for her abstract at the “Réseau de Recherche en Santé Environnementale”. Finally, Caroline is the author of about twenty
institutional, national and international presentations and of several publications including a recent article published in the prestigious publication “Journal of Pediatrics”.
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Twenty fifth Edition of the Vision Network Prize
Matthieu Vanni
Article: Evaluation of receptive field size from higher harmonics in visuotopic mapping using continuous stimulation optical imaging.
After an initial education at the “Ecole Normale Supérieure (Paris)”, Matthieu Vanni specialized in the field of neurosciences at the University Pierre & Marie Curie (DEA, Paris 6). Interested in the opportunities that new methods in brain imaging provide, he decided to complete his formation by an additional training in biomedical imaging (DESS in electronic imaging). This double skill allowed him to occupy a position of research assistant at the « Commissariat à l’Énergie Atomique » in France where he had participated to the development of a nuclear imaging device for animal research currently distributed by Biospace Lab. Since 2004, he has begun a PhD in Biomedical Sciences at the University of Montreal to work on the quantification and the description of cortical maps in the visual system (supported by the Government of Canada and the University of Montreal). The study of the precise organization of the cortex in vivo requires the use of high resolution imaging methods from large portions of brain that only optical imaging of intrinsic signals can provide. For this reason, he joined the Casanova Lab at the School of Optometry which has the most advanced imaging platform of this type in Canada (funding CIHR, NSERC and NIH). Since 2006, he has also worked very closely with the laboratory of Frederic Lesage at the Polytechnic to develop projects related to the development of quantitative methods in optical imaging. The article presented here deals with one aspect developed during this collaboration: Since the 90s, optical imaging of intrinsic signals is the functional imaging technique that has yielded the best spatial resolution over large portions of cortex. However, signal is mainly contaminated by the strong contribution of vascular noises. Many strategies have been developed to reduce this contribution, including a recent approach based on the periodic stimuli coupled to a continuous recording of images and spectral analysis of the response over the time. This approach has led to an increase of 10x the signal to noise ratio but has so far not taken into account the contribution of neurovascular coupling and is only limited to the analysis of a single harmonic. In the article presented here, a model was developed to assess the neural response profile, taking into account the neurovascular coupling and the response to multiple harmonics. This approach was used to assess the size of receptive fields based on the width of the optical response for a drifting bar. This new evaluation paradigm of the receptive field size map may therefore be a fundamental tool for studies looking at the impact of some diseases in the spatial integration of neurons in the retina or brain such as glaucoma.
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 Patrice Voss
Article: Adaptation to sensory loss.
Patrice Voss received his PhD degree in psychology in 2009 from the University of Montreal, working under the supervision of Dr Franco Lepore. He is currently a McGill post‐doctoral researcher working with Dr Robert Zatorre at the MNI and BRAMS. Using several brain imaging tools (fMRI, DTI, VBM) and several behavioral variables (sound localization, pitch and melody discrimination), his research aims to identify the functional and anatomical correlates of enhanced auditory and tactile abilities observed in blind individuals, and to better ascertain the specific impact of the age of onset of blindness on both the brain and behavioral adaptations.
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Twenty fourth Edition of the Vision Network Prize
Wassim Chatoo
Article: Bimodal modulation and continuous stimulation in optical imaging to map direction selectivity.
Wassim Chatoo, born in Democratic Republic of Congo, had arrived to Canada in 1999
where he started his collegial studies in fondamental sciences. After obtaining a bachelor
in biology at UQAM, he sustained his post-graduate studies at the University of
Montreal, under the supervision of Dr Gilbert Bernier at the Maisonneuve-Rosemont
hospital. Dr Bernier is a member of Reseau Vision and is affiliated with the departement of ophtalmology of the University of Montreal. Mr Chatoo enrolled to Bernier’s lab in
2004 as a master student before doing a passage direct to PhD in 2006. The outcome of
his works was published in several scientific papers in high impact journals. His first
publication in 2009, as the main author, in Journal of Neuroscience (impact factor 7.48)
was selected for one of the most interesting papers published in biological sciences over
the world in 2009 (Faculty of 1000 Biology). This paper had an important media
coverage including press release, TV coverage (le téléjournal de Radio-Canada) and radio
interviews (CBC, 98.5 Fm Dutrizac). His second paper submitted to Stem Cells journal
(impact factor 7.74), also as the main author, was recently accepted for publication and
his third paper is in revision in Antioxidants Redox Signaling journal (impact factor 6.19).
Moreover, Mr Chatoo had also participated in numerous published works as second and
third co-autor ((Journal of Neuroscience in 2009 and 2010).
During his PhD studies, Mr Chatoo won several prices for his oral and poster
presentations at different scientific meetings. He also received the Suzanne Véronneau-
Troutman research award during his doctoral studies. This price is awarded to the best
competent student of the ophtalmology departement. He also won Master and PhD
research awards from le Fond de recherche en ophtalmologie (FROUM) during his
master and PhD studies.
Mr Chatoo also attended multiple national and international meetings, like the 3rd
Canadian Conference of Development biology, held at Mont-Tremblant. He also assisted
to the annual meeting of ISSCR considered as the world’s premier stem cell research
event and which was held in Barcelona in July 2009.
Mr Chatoo was recently accepted to Laval University at Quebec, where he is planning to
start his medical studies.
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Twenty third Edition of the Vision Network Prize
Matthieu Vanni
Article: Bimodal modulation and continuous stimulation in optical imaging to map direction selectivity.
After an initial education at the Ecole Normale Supérieure (Paris), Matthieu Vanni specialized in the field of neurosciences at the University Pierre & Marie Curie (DEA, Paris 6). Interested in the opportunities that new methods in brain imaging provide, he decided to complete his formation by an additional training in biomedical imaging (DESS in electronic imaging). This double skill allowed him to occupy a position of research assistant at the Ť Commissariat ŕ lÉnergie Atomique ť in France where he had participated to the development of a nuclear imaging device for animal research currently distributed by Biospace Lab.
Since 2004, he has begun a PhD in Biomedical Sciences at the University of Montreal to work on the quantification and the description of cortical maps in the visual system (supported by the Government of Canada and the University of Montreal). The study of the precise organization of the cortex in vivo requires the use of high resolution imaging methods from large portions of brain that only optical imaging of intrinsic signals can provide. For this reason, he joined the Casanova Lab at the School of Optometry which has the most advanced imaging platform of this type in Canada (funding CIHR, NSERC and NIH). Since 2006, he has also worked very closely with the laboratory of Frederic Lesage at the Polytechnic to develop projects related to the development of quantitative methods in optical imaging. The article presented here deals with one aspect developed during this collaboration:
Direction selectivity is a very important parameter in vision and some cortical structures are organized in map to optimize processing: this is the case in the area MT of primates or in the primary visual cortex of carnivores. The use of optical imaging can be use to reveal these maps but the visual response is usually 10,000 to 100,000 times lower than the vascular noise which often compromises their quantification in reasonable time scales (hours). A new paradigm based on continuous stimulation and Fourier analysis has been developed and has increased by 10x the signal to noise ratio which allows shorter recording session (tens of minutes). This new strategy provides great benefits when the motion selectivity is evaluated in studies involving reversible lesions (injection of pharmacological agents or cooling inactivation) or when many parameters are measured (e.g. speed, coherency ...).
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Twenty second Edition of the Vision Network Prize
Jun II Kang
Article: Cholinergic pairing with visual activation results in long-term enhancement of visual evoked potentials.
My first interest in vision started with visual memory, when I was studying in Handong University in Korea where I received my bachelor degree. I was amazed how the complexity of the brain could be related to such various functions in human behaviour. Especially when I joined the laboratory of Dr. Elvire Vaucher in University of Montreal as a graduate student, I was fascinated by the mechanism of visual memory. I am presently doing my Ph.D. in neuroscience to reveal the role of neurotransmitter acetylcholine (ACh) during the process of visual information. ACh is an important molecule in brain categorized in two groups (i.e. nicotinic and muscarinic; according to its stimulating agonist) which is shown to be involved during cognitive function such as learning or attention. Since enlargement of cortical map could result as an expansion of capacity, I am particularly interested about long-term effect of ACh during the plasticity in adult primary visual cortex (V1).
The article submitted for the contest is a study where we measured the visual evoked potential (VEP) in V1 while the rat was pharmacologically injected (Carbachol: agonist of ACh, CCh). During our study we demonstrated that a unique injection of CCh in V1 induces an increase of VEP when it was paired with the visual stimulation. We also showed that an electrical stimulation of the horizontal diagonal-band of Broca –the major distributor of ACh in V1- results a similar augmentation of VEP. Although both effects endure for several hours, a pre-injection of muscarinic and nicotinic antagonist inhibits this enhancement. Our results signify that the cholinergic agent induced enhancement of cortical responses involves both presynaptic and postsynaptic process. Moreover, inhibition of N-methyl-D-aspartate (NMDA) receptor (NMDAR) also suppressing the CCh-induced effect indicates that the underlying mechanism resembles with long-term potentiation -mechanism occurring during memory formation. To summarize, our data show that the release of ACh during the treatment of visual information could result in the augmentation of the process capacity in a long-term way in V1. This enhancement can be related to cognitive function such as learning and memory.
Future study will be to examine the effect of cholinergic system during vision restoration. I am now analyzing the effect of ACh in V1 on a behavioural level through a water maze. I will also observe its influence during the recovery of cortical response into V1 of laser induced retinal lesioned rats (co-work with Dr. Levin: Maisonneuve-Rosemont hospital).
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Twenty first Edition of the Vision Network Prize
Mylène Pouliot
Article: Quantitative and regional measurement of retinal blood flow in rats using N-isopropyl-p-[14C]-iodoamphetamine ([14C]-IMP).
I completed a B.Sc. in Pharmacology at the University of Sherbrooke in 2006. I began a Master degree in physiology at the University of Montreal supervised by Dr Elvire Vaucher (École d’optométrie) and Dr Réjean Couture (Department of physiology) and have transferred to PhD. At the beginning of my Master degree, I received the support student recruitment bursary from the Vision Research Network. Between 2007 and 2009, I received two academic achievement awards from the Faculty of Graduate Studies and a scholarship from the Foundation Fighting Blindness.
The objective of my research project is to study the retinal vascular alterations contributing to retinal blood flow dysfunction in diabetic retinopathy. To measure retinal blood flow, Dr Vaucher and I have recently developed an autoradiographic technique to obtain quantitative values (to compare different groups of animals) and regional measurements (to measure blood flow on the overall retina). Quantitative and regional measurement of retinal blood flow is essential to evaluate regulation of ocular circulation in pathological situation as most retinal diseases are characterized by subtle changes in microcirculation. The article submitted for Vision Research Network contest presents a new technique for the measurement of retinal perfusion in rat and demonstrates its capacity to detect regional changes of blood flow in the retina. Retinal blood flow in rat was measured following an intravenous injection of [14C]-IMP; a radioactive tracer commonly used for the investigation of cerebral blood flow. This lipophilic tracer diffuses into the retina proportionally to blood flow and has a low post-mortem diffusion which limits contamination of retinal blood flow by choroidal circulation. Because of these tracer properties, local blood flow can be measured on whole-mount retinas by quantitative autoradiography. In this study, the method using [14]-IMP in rats was validated for its capacity to detect retinal blood flow augmentation induced by hypercapnia. Results showed that this technique is sensitive enough to detect variation of retinal blood flow at two different hypercapnic levels and can be used to measure blood flow in central as well as peripheral retina. Thus, this technique could be a powerful tool to study retinal blood flow changes in animal models of ocular diseases such as diabetic retinopathy, or to evaluate the potential of new pharmacological treatments. To complete my PhD, I am now using this technique to study the regulation of retinal blood flow in diabetic rats and the effect of a treatment targeting kinin receptors which are involved in inflammatory mechanisms and retinal vascular damage in diabetes.
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Twentieth Edition of the Vision Network Prize
Allison L. Dorfman
Article: Functional and Structural Changes Resulting From Strain Differences in the Rat Model of Oxygen.
Following the completion of the B.Sc. program at McGill University with a major in Physiology and a minor in Pharmacology and Therapeutics in 2000, I entered the PhD graduate program in Pharmacology and Therapeutics under the co-supervision of Drs. Chemtob and Lachapelle. My research is focused on a model of retinopathy of prematurity (ROP) which is a disease that affects prematurely born infants that can ultimately lead to blindness.
Oxygen-induced retinopathy (OIR) in the neonatal rat provides a model for ROP and other diseases that are characterized by abnormal retinal angiogenesis. In order to better understand the pathophysiology of this retinopathy, I have carried out electrophysiological (flash ERGs and VEPs, multifocal ERGs), histological, immunohistochemical and vascular studies in both albino and pigmented rat strains following exposure to hyperoxic conditions.
The results from my first study showed that trolox C, a water soluble analogue of vitamin E, is able to at least partly prevent retinal functional and structural damage as evaluated with the ERG and histology, respectively, when administered throughout the hyperoxic phase. These results suggest a role for free radicals among other factors in creating the pathogenesis of OIR.
Our findings with Trolox C led to the current study comparing the pigmented Long Evans and albino Sprague Dawley rat models of OIR in order to determine whether melanin, also known to act as an antioxidant, plays a role in protecting the retina from oxygen toxicity. In humans, studies that compared the racial incidence of retinopathy of prematurity (ROP) suggested that ocular pigmentation might offer protection against the development of severe ROP. The severity of the OIR was determined by examining retinal flatmounts (retinal vasculature assessment), protein level quantification and cellular localization of fibroblast growth factor (FGF)-2 and ciliary neurotrophic factor (CNTF; Western blot analysis and immunohistochemistry, respectively), retinal histology, and photopic and scotopic electroretinograms (ERGs). Surprisingly, irrespective of the parameter considered, vascular, structural and functional deficits resulting from postnatal hyperoxia were significantly more pronounced in pigmented Long Evans rats compared to albino Sprague Dawley rats. We have already begun to use various immunohistochemical techniques (anti-synaptophysin, anti-PKC, anti-recoverin, anti-mGluR6, anti-bassoon and anti-calbindin) in order to further elucidate the mechanism by which synaptic retraction occurs.
In conjunction with my graduate studies, I’ve been working at the Montreal Children’s Hospital ERG clinic since 2002 (department of ophthalmology) where I see patients with diseases such as retinitis pigmentosa, congenital stationary night blindness and age related macular degeneration, among others. The results from both my laboratory and clinical work have been presented at a number of international and local conferences.
From 1999-2000, I was given the opportunity to pursue a research project for completion of the minor program in Pharmacology and Therapeutics under the supervision of Drs. De Koninck and Ribeiro-Da-Silva. This work was focused on the characterization of cells in Lamina I of the spinal dorsal horn, an area involved in the relay of nociceptive and thermoreceptive information. This project, as well as my earliest research experience (1996-1998) at the Jewish General Hospital (supervised by Drs. Mitmaker and Black), involved the generation and organization of data from colon, head and neck cancer patients, were all instrumental in helping me realize my passion for research and my eagerness to pursue a doctoral degree.
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Nineteenth Edition of the Vision Network Prize
Frédéric Lebrun-Julien
Article: Inhibition of p75NTR in glia potentiates TrkA-mediated survival of injured retinal ganglion cells.
I began my studies in science at the University of Sherbrooke in Biotechnology. Then, I joined the laboratory of Dr. Adriana Di Polo at Montreal University in the Department of Pathology and Cell Biology to continue my graduate studies. Following a direct passage, I’m presently doing my Ph.D.. The goal of my project of thesis is to determine the specific role of the two receptors of the nerve growth factor (NGF) in the adult retina: TrkA and p75NTR. Moreover, these two receptors are expressed in different cellular populations in the adult retina, the Müller glia (p75NTR) and the retinal ganglion cells (RGCs) (TrkA). I am interested in the neuron-glia interaction following injury of optic nerve or after excitotoxic damages caused by N-methyl-D-aspartic acid (NMDA).
The article submitted for the contest is a study where we used new peptidomimetic ligands (agonists or antagonists) with specific activity for the receptors TrkA and/or p75NTR in order to determine the role of each receptor on the survival of the axotomized RGCs. We showed that the specific activation of the TrkA receptor led to marked neuroprotection of axotomized RGCs, while intraocular administration of recombinant nerve growth factor did not promote survival. Surprisingly, injection of an antagonist of p75NTR in Müller cells induced the survival of RGCs after the axotomy. RGCs of knockout mouse for the receptor p75NTR also show a resistance following the optic nerve transection. Collectively, our data show the neuroprotection effect of new peptidomimetic compounds of the neurotrophins in the retina and reveal a novel mechanism by which p75NTR expressed on retinal glia can profoundly influence neuronal survival.
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Eighteenth Edition of the Vision Network Prize
Madeleine Fortin
Article: Wayfinding in the blind: larger hippocampal volume and supranormal spatial navigation, publié dans Brain.
I received my bachelor’s degree in psychology in 2003 at the Université de Montréal. During the last year of my undergraduate studies I joined the group of Dr Franco Lepore. I became interested in cerebral plasticity and spatial abilities in the blind while working in his laboratory. I collaborated in a research project looking into the auditory abilities of early- and late-onset blind individuals. The results show for the first time that late-onset blind individuals show above-normal spatial abilities while compared to sighted individuals thus suggesting that significant compensation can occur in adults. These data have been published in Current Biology. The originality and quality of this work has been underlined in the Québec Science top ten discoveries of 2004.
I began a master’s in psychology and then my doctorate studies in clinical neuropsychology under the supervision of Dr Lepore and co-directed by Dr Dave St‑Amour. I am interested in the spatial orientation abilities of the blind and also in the neural correlates of spatial orientation. The goal of my fist project was to investigate the topographical abilities of the blind. Previous studies on mental rotation in the blind had so far focused on the comparative study of two objects. In marked contrast to these studies, my experiment focuses on mental rotations centered on the environment rather than on external objects. This work was presented in many scientific meetings and has been published in 2006 in NeuroReport. The award for the best poster presentation of the Journée Scientifique du Département de psychologie de l’Université de Montréal has also highlighted the quality of this work.
The goal of the paper presented for this contest was twofold. We first explored the navigational abilities of early- and late-onset blind individuals. We also explored structural changes in the hippocampus, a structure well known to be involved in spatial processing. Remarkably, we not only showed that blind individuals possess superior navigational skills than matched sighted blindfolded controls on several spatial tasks, but also showed for the first time a significant volume increase of the hippocampus in blind individuals, irrespective of whether their blindness was congenital or acquired. Overall, our results shed new light not only on the construction of spatial concepts and the non-necessity of vision for its proper development, but also on the hippocampal plasticity observed in adult blind individuals who have to navigate in this space. The results of this study were also presented in several local and international scientific meetings and have been published in the prestigious journal Brain. The value of this work has been highlighted by the presentation of the figures of my article on the cover of the journal.
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Seventeenth
Edition of the Vision Network Prize
Przemyslaw Sapieha
Article: The succinate receptor GPR91 in neurons plays a major role in retinal angiogenesis.
Mike (Przemyslaw) Sapieha received his Ph.D in Molecular Neurocytology in 2005 and has since been working as a postdoctoral fellow under the mentorship of Dr. Sylvain Chemtob at the Ste-Justine Research Center in Montreal. He initially began his research career in industry at MethylGene Inc elucidating mechanisms of gene silencing by novel RNA-inhibitors. This interest in gene modulation was pursued during his doctorate where he worked on elaborating neuroprotective and regenerative strategies by means of gene therapy. It was here that he first started working with the retina and visual system. Mike pursued working on the retina in the Chemtob Lab where he tackled issues related to ischemic retinopathies such a that of retinopathy of prematurity (ROP). Here, they put forward two important concepts pertaining to the unprecedented involvement of the Krebs cycle metabolite succinate in neuroretinal angiogenesis. First, their work indentified succinate as a biologically active molecule that accumulates in the hypoxic retina and via its recently identified cognate receptor, GPR91, contributes significantly to vessel growth both during development as well as that associated with pathological proliferative ischemic retinopathies such as ROP. Secondly, they demonstrated that retinal ganglion neurons act as the principal respondents to succinate and consequently recognized these cells as key sensors of hypoxic stress, capable of reinstating vascular supply to an ischemic retina by governing the release of a pleiotropy of major angiogenic factors. Collectively, their findings provide a novel target for the design of effective strategies to counter vascular injuries by modulating (insufficient [eg. stroke] or excessive [aberrant preretinal neovascularization such as in ROP]) revascularization. Their work has been published in the October 2008 issue of the journal Nature Medicine.
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Paper in the Forum
Sixteenth
Edition of the Vision Network Prize
Anteneh Argaw
Article: Protein kinase A modulates retinal ganglion cell growth during development.
Visual impairment is a major medical problem and an imminent social concern for which presently, there is no cure or treatment. Neuro-visual deficiencies could be caused by several diseases, including congenital disorders (optic nerve hypoplasia or atrophia), trauma, age-related macular degeneration, or secondary to other pathologies (glaucoma, diabetic retinopathy). Thus, the main goal of the proposed project is to understand and characterise molecular mechanisms with significant potential to treat neuronal impairment of the visual system and improve the sight and quality of life of patients.
Following differentiation, retinal ganglion cell (RGC) axons, tipped at their distal end by the growth cone (GC), navigate through relatively long distances in a highly directed manner in order to establish functional synapses with thalamic and superior colliculus (SC) neurons. This is achieved with the help of extracellular guidance molecules which steer RGC axon growth by regulating GC morphology by means of attractive and/or repulsive mechanisms. The cyclic nucleotide cAMP is a key intracellular second messenger that plays an essential role in numerous neuronal functions such as cell survival, axon regeneration, and GC behaviour to guidance cues. For example, elevated intracellular cAMP levels enhance survival of CNS neurons. In RGCs, an increase in survival rate is attributed in part by cAMP’s ability to potentiate the cell responsiveness to trophic factors in vitro. A large body of evidence supports a role for cAMP in axon regeneration. Accordingly, treatment of injured neurons with a cocktail of trophic factors and cell permeable analogs of cAMP results in an increased number of regenerating axons, even promoting their growth through inhibitory environment.
The importance of cAMP regulation of axonal growth, navigation and the mechanism by which it exerts its role is further confirmed by a recent study which demonstrated that during the establishment of the retinotopic map, cAMP oscillations in the GC appear to be the mechanism by which cAMP mediates ephrin-A-induced collapse and retraction retinal axons in vitro. Despite the abundance evidence describing the role played by cAMP and its downstream effector Protein Kinase A (PKA) in neuron survival and axon regeneration, its role during development remains unknown.
In the adult brain, endocannabinoids exert an important neuromodulatory function by acting as retrograde messengers to regulate the function of many synapses. Endocannabinoids act mainly via their Gi-coupled protein receptors CB1 and CB2. Both receptors are coupled negatively to adenylate cyclase, an enzyme regulating the synthesis of cAMP. Due to their presence at the fetal and early postnatal periods, it has been proposed that endocannabinoids and their receptors might be involved in several developmental events, such as cell proliferation and migration, axon guidance and synaptogenesis. Recently, activation of CB1 receptors at the GC has been proposed to induce an inhibitory effect on GABAergic interneurons in vitro.
The main objectives of my thesis are: 1) To evaluate the role of the cAMP/PKA pathway during early neonatal development of RGCs, and to test the hypothesis that modification of retinal cAMP levels will alter retinal axon growth in vitro and in vivo. 2) To identify the functional role of cannabinoids and their receptors during RGC axon guidance and the mechanisms by which they exert their effects in vitro and in vivo.
Since 2005, I have received several academic achievement awards from the faculty of graduate studies, the school of optometry and the department of biomedical science at the Université de Montréal. In addition, I received the 2008 Synapse Award from the CIHR. My doctoral studies are funded by E.A. Baker and CIHR..
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Fifteenth
Edition of the Vision Network Prize
Allison L. Dorfman
Article: Early Manifestations Of Postnatal Hyperoxia On The Retinal Structure
And Function Of The Neonatal Rat.
Following the completion of the B.Sc. program at McGill University with a major in Physiology and a minor in Pharmacology and Therapeutics in 2000, I entered the PhD graduate program in Pharmacology and Therapeutics under the co-supervision of Drs. Chemtob and Lachapelle. My research is focused on a model of retinopathy of prematurity (ROP) which is a disease that affects prematurely born infants that can ultimately lead to blindness.
Oxygen-induced retinopathy (OIR) in the neonatal rat provides a model for ROP and other diseases that are characterized by abnormal retinal angiogenesis. In order to better understand the pathophysiology of this retinopathy, I have carried out electrophysiological (flash ERGs and VEPs, multifocal ERGs), histological, immunohistochemical and vascular studies in both albino and pigmented rat strains following exposure to hyperoxic conditions.
The results from my first study showed that trolox C, a water soluble analogue of vitamin E, is able to at least partly prevent retinal functional and structural damage as evaluated with the ERG and histology, respectively, when administered throughout the hyperoxic phase. These results suggest a role for free radicals among other factors in creating the pathogenesis of OIR.
The findings from this paper led to a second study of OIR in a pigmented rat model in order to determine whether melanin, also known to act as an antioxidant, plays a role in protecting the retina from oxygen toxicity. Surprisingly, these results have suggested that this rat strain undergoes an even more severe form of OIR, with greater retinal vascular, structural and functional consequences. My third study includes the use of immunohistochemical techniques (anti-synaptophysin, anti-PKC, anti-recoverin, anti-mGluR6, anti-bassoon and anti-calbindin) in order to determine the mechanism by which OPL retraction occurs. Finally, I am currently using immunoblotting techniques (Western blots) to determine whether changes in regulation of specific neurotrophic factors (BDNF, CNTF and FGF-2) might be involved in the protection or susceptibility of the retina throughout different hyperoxic exposures.
In conjunction with my graduate studies, I’ve been working at the Montreal Children’s Hospital ERG clinic since 2002 (department of ophthalmology) where I see patients with diseases such as retinitis pigmentosa, congenital stationary night blindness and age related macular degeneration, among others. The results from both my laboratory and clinical work have been presented at a number of international and local conferences.
From 1999-2000, I was given the opportunity to pursue a research project for completion of the minor program in Pharmacology and Therapeutics under the supervision of Drs. De Koninck and Ribeiro-Da-Silva. This work was focused on the characterization of cells in Lamina I of the spinal dorsal horn, an area involved in the relay of nociceptive and thermoreceptive information. This project, as well as my earliest research experience (1996-1998) at the Jewish General Hospital (supervised by Drs. Mitmaker and Black), involved the generation and organization of data from colon, head and neck cancer patients, were all instrumental in helping me realize my passion for research and my eagerness to pursue a doctoral degree.
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Fourteen
Edition of the Vision Network Prize
Woo Young Choi
Article: Responses of Collicular Fixation Neurons
to Gaze Shift Perturbations in Head-Unrestrained
Monkey Reveal Gaze Feedback Control
I was intrigued by the brain’s ability to coordinate different mobile segments of our body to achieve a common goal. For example, how can the brain control goal-directed, multi-joint movements such as arm-reaching movements to grasp an object and eye-head gaze shifts used to scan our visual surrounds? With this question in mind I started my Ph.D. training at McGill University with Dr. Daniel Guitton. Dr. Guitton was one of the proponents of a controversial hypothesis that coordinated eye-head gaze shifts are controlled by an internal feedback loop and that the superior colliculus, a midbrain visual-motor structure, is implicated in this process. In this hypothesis, the superior colliculus resides within a gaze feedback control loop that assures movement accuracy by nullifying an error or “mismatch” signal, a difference between final and current gaze positions. This hypothesis created a long-standing controversy that has divided the motor-control field into two camps, one proposing that the superior colliculus is within a gaze feedback loop while the other maintaining the traditional view that the superior colliculus carries an open-loop, ballistic eye command. I thought that solving this problem will be a major contribution because, in addition to uniting different views and ending the important controversy in the field, the results from my research will be critical to the development of models of the neural circuitry that controls how we look about our surrounds, a function most critical for vision. Now the findings from my research strongly support the existence of a gaze feedback loop and show that the superior colliculus is informed about its calculations. These observations are incompatible with the traditional view that the superior colliculus carries an open-loop, ballistic eye command.
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Thirteenth
Edition of the Vision Network Prize
Vincent Pernet
Article:A role for polyamines in retinal ganglion cell excitotoxic death
I carried out my undergraduate studies at Reims, in France (1995 to 1998). During the last year of my undergraduate studies I participated in a CREPUQ exchange program at McGill University in Montreal. During this time, I was able to refine my interest in neuroscience. After having completed my Master’s in Neurological Sciences (1999-2001) at the Université de Montréal in the laboratory of Dr Michel Anctil I joined the group of Dr Adriana Di Polo at the Department of Pathology and Cellular Biology. My PhD was entitled « Les Voies de Signalisation du Facteur Neurotrophique Dérivé du Cerveau (BDNF) dans la Survie Neuronale et la Régénération Axonale des Cellules Ganglionnaires de la Rétine Adulte Blessée ». My doctoral work demonstrated that targeted activation of the MAPK1/2 signalling pathway stimulated the survival of injured retinal ganglion cells (RGC), but was insufficient to induce the regeneration of sectioned axons in the optic nerve (Vincent Pernet, William W. Hauswirth and Adriana Di Polo (2005) J. Neurochem., 93 (1):72-83). In the second part of my thesis, we discovered that treatment with BDNF combined with injury of the crystallin lead to a greater survival of RGCs, but completely inhibited the regrowth of lesioned optic nerve axons (Vincent Pernet and Adriana Di Polo (2006) Brain, 129 (Pt4):1014-26). For the last part of my PhD work, we observed that the endogenous synthesis of polyamines participated in excitotoxic death caused by the activation of inotropic glutamate receptors of the N-methyl-D-aspartate (NMDA) family. This type of death is implicated in mechanisms that contribute to damage caused by ischemia in the SNC. Therefore, by showing that a pharmacological blockade of the polyamine synthesis pathway reduced excitotoxic death, our results suggest a new therapeutic strategy to reduce damage related to ischemia in the retina (Vincent Pernet, Philippe Bourgeois and Adriana Di Polo (2007) J. Neurochem.; attached article).
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Twelth
Edition of the Vision Network Prize
Sandrine Joly
Article:Neuroprotection in the juvenile rat model of light-induced retinopathy: Evidence suggesting a role for FGF-2 and CNTF
Sandrine Joly carried out her Master’s degree work at the “Institut de Recherche Clinique de Montréal (IRCM)” prior to joining the laboratory of visual electrophysiology of Dr Lachapelle in 2001 for her doctoral thesis. Sandrine’s thesis aimed to characterize the functional and structural damage in the retina following intense light exposure during the postnatal maturation period in albino rats. Using electroretinography (ERG) and optical microscopy, Sandrine demonstrated the surprising resistance of juvenile retinas to light damage as compared to what is seen in adults. These results have been the subject of her first two articles (IOVS, 2006, 47: 3202; Doc. Ophthalmol., 2006, 113: 93).
Consequent to her research into the mechanisms responsible for the greater resilience of juvenile retinas to light stress, Sandrine developed an interest for neurotrophic factors. Within the context of collaboration between the laboratories of Dr Lachapelle and Dr Di Polo, Sandrine measured the variations in endogenous CNTF (Ciliary Neurotrophic Factor) levels, as well as FGF-2 (Fibroblast Growth Factor-2) and BDNF (Brain-Derived Neurotrophic Factor). These measures were carried out using protein staining (Western Blot) and by immunohistochemistry, following the exposure of young animals to light stress. The results show that the retinas of juvenile animals over express CNTF and FGF-2 in comparison to adult animals exposed to the same conditions.
This last part of her thesis has allowed Sandrine to demonstrate that important changes of some neurotrophic factors in the juvenile retina, following exposure to light, suggests that other molecular mechanisms may intervene. Put together, Sandrine’s work brings to light the importance of differences in physiological and molecular responses in the retina to light exposure in the juvenile and adult.
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Eleventh
Edition of the Vision Network Prize
Sandra Leh
Article: Absence of S-cone input in human blindsight following hemispherectomy
I practiced as a licensed Orthoptist (Health Professional
in Neuroopthalmology) for seven years in Hamburg,
Germany. My work involved the prevention, diagnosis,
assessment, treatment and rehabilitation of disorders
of vision, eye movements and eye alignment in
children and adults. These disorders included
childhood eye diseases, such as amblyopia, strabismus,
double vision, ametropia; neurological eye diseases
such as eye movement difficulties (palsies, Grave's
disease, myasthenia, blow-out fracture), visual
field deficits, pupil defects and nystagmus; and
the differential diagnosis of dyslexia and learning
disabilities.
My neuroophthalmological experience as an Orthoptist
drew my interest towards (residual) visual abilities,
learning disabilities, neurological disorders
and its neuronal mechanisms, and directed me towards
research in neuroscience. I was particularly interested
in the blindsight phenomenon, which is the ability
to respond to visual stimuli in the blind visual
field without awareness. I received my M.Sc. in
Clinical Psychology (Major: Cognitive Psychology/Neuropsychology,
Neurology) from the University of Hamburg in Hamburg,
Germany in 2003. After completing my M.Sc, I worked
for six months at the Brain Imaging Center of
the Douglas Hospital in Montreal, Canada until
I began my current doctoral studies in Neuroscience
at McGill University/Montreal Neurological Institute
and Hospital (MNI) in Montreal, Canada in 2003.
My doctoral work is currently being supervised
by Dr. Alain Ptito, a clinical neuropsychologist
who does research in residual vision in hemispherectomized
patients and post-traumatic brain disorders and
I am currently funded by a doctoral scholarship
from the Fonds de recherche en santé du
Québec (FRSQ).
For my research, I have implemented an innovative
brain imaging technique, Diffusion Tensor Imaging
(DTI) Tractography, which enables reconstruction
of white matter tracts in vivo. In DTI, the magnetic
resonance signal is sensitized to the random motion
(diffusion) of water molecules, to provide local
measures of the magnitude of water diffusion,
which can be related to fiber structure in the
brain. I used a probabilistic diffusion tractography
algorithm that is able to trace likely fiber pathways
between grey matter structures. We used DTI tractography
to demonstrate an association between the presence
of blindsight and reconstructed superior colliculi
fiber tracts in hemispherectomized human subjects,
in support of the hypothesis that this subcortical
structure plays a pivotal role in this type of
blindsight.
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Tenth
Edition of the Vision Network Prize
Mirna Sirinyan
Article: Hyperoxic exposure leads to nitrative stress and ensuing microvascular degeneration and diminished brain mass and function in the immature subject
Mirna Sirinyan graduated with great distinction in June 2001 from the department of Microbiology and Immunology at McGill University. She was awarded an NSERC scholarship to pursue her M.Sc. under the supervision of Dr. Joseph Mancini at Merck Frost where she studied the role of the enzyme membrane prostaglandin E2 synthase-1 (mPGES-1) in rheumatoid arthritis. She then commenced her PhD in Pharmacology and Therapeutics (McGill) in Dr. Sylvain Chemtob’s laboratory at Sainte-Justine Hospital in September 2003. Her PhD focuses on the neurovascular degeneration and repair that occurs following hyperoxic exposure in premature infants. Her current publication in Stroke extended findings of the deleterious effects of hyperoxia in the premature retina to the brain, and provided evidence that hyperoxia elicits microvascular degeneration (mostly in the cortical regions of the immature brain), diminished brain mass and cerebral functional deficits. She is currently working on unveiling novel properties for mitochondrial Krebs cycle metabolites succinate and α-ketoglutarate in governing retinal angiogenesis by acting through specific cognate GPCRs, GPR91 and GPR99 respectively. The identification of these receptors conveying signaling of the Krebs cycle intermediates provides new and potentially important therapeutic targets for countering abnormal pre-retinal neovascularization seen in ischemic retinopathies.
Mirna Sirinyan is the author of a number of publications and is the recipient of several prizes including the FRSQ prix d'excellence in June 2003, the Young Investigator's award in November 2004 at the Free Radicals and Biology of Medicine conference, the best poster presentation at the Nature Biotechnology conference on Angiogenesis and Diseases in February 2006, and the Melville Prize at the McGill Pharmacology Research Day in June 2006. She has been funded by the Heart and Stroke Foundation of Canada (doctoral scholarship) throughout her PhD, which she will be completing in the course of 2007.
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Marie-Ève Doucet
Article: Cross-modal reorganization and speech perception in cochlear implant users
Marie-Ève Doucet completed her Masters degree in experimental neuropsychology at the Université de Montréal, under the supervision of Franco Lepore, Canada research chair and tenured professor at the department of Psychology, and co-directed by Jean-Pierre Gagné, tenured professor and director of the department of orthophonie-audiologie. The project concentrated on the enhanced sound localisation capacities by the visually impaired. The title of the thesis was: Le traitement des indices spectraux dans la localisation sonore chez les aveugles. The article based on this masters degree was titled Blind subjects process auditory spectral cues more efficiently than sighted individuals (M.-E. Doucet . J.-P. Guillemot . M. Lassonde . J.-P. Gagné . C. Leclerc . F. Lepore. (2005) Experimental Brain Research 160: 194-202). The article proposes that inter-modal plasticity could explain the enhanced auditory capacities in the blind, as compared to sighted individuals. This work was presented in poster form at two international conferences and oral presentations in two national conferences. Thereafter, Marie-Ève became interested in plasticity following the restoration of a sensory modality. In order to attain this objective she decided to study hearing impairments and cochlear implants, an apparatus that restores hearing in the hearing impaired. She completed a PhD in neuropsychology at the Université de Montréal in this area, once again under the supervision of Franco Lepore and co-directed by François Bergeron, adjunct professor at Université Laval. The title of the thesis was Plasticité des aires visuelles chez le sujet sain et chez l’implanté cochléaire. The objective of the project was to assess the state of the visual system among the hearing impaired to determine if they can understand speech after receiving a cochlear implant. The first article from this thesis was: Development of visual- evoked potentials to radially modulated concentric patterns (M.-E. Doucet, F. Gosselin, M. Lassonde, J.-P. Guillemot, F. Lepore (2005) Neuroreport 16: 1753-1756.). It shows that the processing of radially modulated stimuli is not mature before the age of 13 in humans. The results demonstrated that it is possible to use the same stimuli with subjects suffering from a sensory deficiency to examine the cerebral reorganisation due to sensory deprivation. The next article, the one rewarded by the Vision Network Prize, is: Cross-modal reorganization and speech perception in cochlear implant users. (M.-E. Doucet, F. Bergeron, M. Lassonde, P. Ferron et F. Lepore (2006) Brain 129: 3376-83.). It concerns the visual analysis in the deaf before and after a cochlear implant. The work during her PhD has been presented as five poster presentations in national and international conferences and three oral communications, of which two were as an invited speaker, at the Smith-Kettlewell Institute (San Francisco) and the California Institute of Technology (Los Angeles).
Ninth
Edition of the Vision Network Prize
Sandra Leh
Article: Unconscious vision:
new insights into the neuronal correlate of blindsight
using diffusion tractography
I practiced as a licensed Orthoptist (Health Professional
in Neuroopthalmology) for seven years in Hamburg,
Germany. My work involved the prevention, diagnosis,
assessment, treatment and rehabilitation of disorders
of vision, eye movements and eye alignment in
children and adults. These disorders included
childhood eye diseases, such as amblyopia, strabismus,
double vision, ametropia; neurological eye diseases
such as eye movement difficulties (palsies, Grave's
disease, myasthenia, blow-out fracture), visual
field deficits, pupil defects and nystagmus; and
the differential diagnosis of dyslexia and learning
disabilities.
My neuroophthalmological experience as an Orthoptist
drew my interest towards (residual) visual abilities,
learning disabilities, neurological disorders
and its neuronal mechanisms, and directed me towards
research in neuroscience. I was particularly interested
in the blindsight phenomenon, which is the ability
to respond to visual stimuli in the blind visual
field without awareness. I received my M.Sc. in
Clinical Psychology (Major: Cognitive Psychology/Neuropsychology,
Neurology) from the University of Hamburg in Hamburg,
Germany in 2003. After completing my M.Sc, I worked
for six months at the Brain Imaging Center of
the Douglas Hospital in Montreal, Canada until
I began my current doctoral studies in Neuroscience
at McGill University/Montreal Neurological Institute
and Hospital (MNI) in Montreal, Canada in 2003.
My doctoral work is currently being supervised
by Dr. Alain Ptito, a clinical neuropsychologist
who does research in residual vision in hemispherectomized
patients and post-traumatic brain disorders and
I am currently funded by a doctoral scholarship
from the Fonds de recherche en santé du
Québec (FRSQ).
For my research, I have implemented an innovative
brain imaging technique, Diffusion Tensor Imaging
(DTI) Tractography, which enables reconstruction
of white matter tracts in vivo. In DTI, the magnetic
resonance signal is sensitized to the random motion
(diffusion) of water molecules, to provide local
measures of the magnitude of water diffusion,
which can be related to fiber structure in the
brain. I used a probabilistic diffusion tractography
algorithm that is able to trace likely fiber pathways
between grey matter structures. We used DTI tractography
to demonstrate an association between the presence
of blindsight and reconstructed superior colliculi
fiber tracts in hemispherectomized human subjects,
in support of the hypothesis that this subcortical
structure plays a pivotal role in this type of
blindsight.
PDF
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Eighth
Edition of the Vision Network Prize
Daniel Chebat
Article: Development of
the commissure of the superior colliculus in the
hamster
I obtained my Bachelor's degree
from Bishop's University in 2002, and then began
my master's in neuropsychology at the Iniversité
de Montréal under the supervision of Dr.
Maurice Ptito. With whom I am now continuing my
PhD in neuropsychology. The present paper, concerns
the development of the commisure of the superior
colliculus (CSC). It is the result of my research
during my master's degree, for which I have received
many prizes (best presentation at the Réseau
Vision 2004, the best scientific presentation
of the Caisse Populaire Desjardins 2005). The
CSC is a mysterious part of the brain of which
we know very little as petains to it's functions.
It is believed to be involved in the interhemispheric
transfer of sensory information. My work was a
first in this area, as no one had yet studied
the development of the normal CSC from the embryo
to adulthood. This work was presented in poster
format at the last Society for Neuroscience Meeting
in Washington in the fall of 2005. Thereafter,
it appeared under article format in the prestigious
Journal of COmparative Neurology.
Having received the Vision Network bursary, I
began my PhD in neuropsychology under the supervision
of Dr. Maurice Ptito. My teaching a class of the
Neurophsyiology of eye movements at the School
of Optometry at the University of Montréal,
I began two projects on navigation by the blind
and sensory substitution. Preliminary results
have been presented at the last scientific day
of the School of Optometry in APril 2006, for
which I received the Novartis prize for the best
scientific presentation.
The above mentionned projects, on which I am presently
working in the context of my PhD, also represent
a first in the area of plasticity of the visual
system as I am working with individuals who are
born blind and that are navigating by means of
sensory substitution. My results were presented
at the Human Brain Mapping meeting (Florence,
2006).
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Seventh
Edition of the Vision Network Prize
Vincent Pernet
Article: Synergistic action
of brain-derived neurotrophic factor and lens
injury promotes retinal ganglion cell survival,
but leads to optic nerve dystrophy in vivo
I obtained my masters in the Neurological
Sciences program with Dr Michel Anctil at the
Université de Montréal from 1999
to 2001. The subject of my masters concerned the
neuroendocrine system of the Renilla koellikeri.
The results from my masters were the object of
three publications. Thereafter, I decided to do
my Doctorate on the mechanisms of neuronal survival.
Since 2001, I have therefore conducted my PhD
in the laboratory of Dr Di Polo at the Department
of Pathology and Cellular Biology at the Université
de Montréal. We use damage of the optic
nerve as a model in order to define strategies
of survival and axonal regeneration via genetic
therapy.
The objective of my thesis project is to determine
the role of MAPK on survival and regenration of
ganglion cells in the retina after damage to the
optic nerve. I am also interested in the effects
of brain derived neurotrophic factor (BDNF) on
axonal regeneration and on the damage caused by
lesions of the optic nerve or NMDA excocitotoxicity.
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Sixth
Edition of the Vision Network Prize
Martin Y. Villeneuve
Article: Pattern-Motion
Selectivity in the Human Pulvinar
For my Ph.D., I am working on cerebral
function using imaging techniques as a measure.
To do this, I went to Denmark in 2002 and 2003
(Aarhus) to learn the basics of positron emission
tomography, under the supervision of Ron Kupers.
During my stay, I had the chance to conduct a
study which is submitted for the Network's prize.
This work has been presented at many meetings:
Human Brain Mapping (Budapest, 2004), Society
for Neuroscience (San Diego, 2004), Journée
Scientifique de l'École d'optométrie
de l'U de M (Montréal, 2005), Journée
scientifique Centre de Recherche en Neuropsychologie
Expérimentale et Clinique (CERNEC, St-Sauveur,
2005), Journée Scientifique du Réseau
Vision (Drummondville, 2004).
Following an invitation to give a conference
at Ruhr-Universität-Bochum in 2002 (Germany),
I was invited in 2003 to stay 6 months as a guest
scientist in the department of Dr. Klauss-P. Hoffmann.
With the support of the International Graduate
School of Neuroscience, I learnt how to use optical
imaging systems. Upon my return to Montréal
in 2004, I was able to get Dr. Christian Casanova's
(my thesis supervisor) system to work. This technique
allows us to get a functional map of cerebral
function with a high spatial resolution (200 microns).
The objective of the projects under way is to
determine the functional relationships between
the Pulvinar and information processing in the
visual cortex. With this technique it is also
possible to get a very high temporal resolution
(1ms), in order to study the temporal dynamics
between the cortex and the Pulvinar when a voltage
sensitive dye is used. In order to complete my
knowledge of optical imaging, I visited the laboratory
of Dr. Birgit Roerig at Baltimore (University
of Maryland), as well as the laboratory of Dr.
Mriganka Sur at MIT (Cambridge). Both of these
trips were partially paid for by the Vision Network
as well as the EA baker Foundation. Both helped
me to develop my knowledge of techniques and mathematical
algorithms that are necessary to analyse an image.
During my masters (1999-2002), I completed two
research projects regarding the visual system
of the cat. The first consisted of determining
the different effects of two anaesthetic agents
on visual function. This work was published in
the Journal of Neuroscience Methods (2003), with
the help of the Vision Network. A second research
project studied the role of neurons in the postero-medial
lateral suprasylvian cortex (PMLS) of the cat
in the perception of complex motion. This project
consisted of characterizing PMLS neurons with
different complex stimuli (RDKs, plaids, …)
in order to determine the role this region plays
in the perception of complex motion. The financing
of this project was also possible thanks to the
Vision Network (FRSQ). This study is presently
in press in the journal Experimental Brain Research.
PDF
version of the article
Fifth
Edition of the Vision Network Prize
Sandrine Joly
Article : Brain-Derived
Neurotrophic Factor Gene Delivery to Müller
Glia Preserves Structure and Function of Light-Damaged
Photoreceptors.
Sandrine Joly completed a master's
degree in molecular biology at the Institut de
Recherche Clinique de Montréal (IRCM) before
beginning her PhD in the laboratory of visual
electrophysiology of Dr Lachapelle in 2001. The
theme of her thesis is the functional and structural
characterisation of damage to the retina induced
par intense light exposure during post-natal maturation
in albino rats. She uses the complementary approaches
of electroretinography (ERG) which measures the
electrical activity of the retina, and optical
and electronic microscopy allowing for a histological
assessment of damage caused by light exposure.
Sandrine's original work demonstrates the surprising
resiliency of the juvenile retina to light produced
damage as compared to the adult. These results
are well documented in the first two articles
which Sandrine is presently preparing. Sandrine
concentrated on neurotrophic factors that could
explain the resiliency of the juvenile retina
to light damage. In a study which was a collaboration
between the laboratories of Dr Lachapelle and
Dr Di Polo, Sandrine contributed to the demonstration
that Ad-BDNF could protect photoreceptors from
light induced stress in the adult rat, by introducing
the gene for BDNF in Müller cells. To determine
whether the endogenous resistance of the juvenile
retina is attributable to the over expression
of neurotrophic factors, Sandrine followed variations
of CNTF, FGF2 and BDNF by immunoblotting (western
blot) and by immunohistochemistry. This fourth
part of Sandrine's research project demonstrated
that there are important changes of certain neurotrophins
in the juvenile retina following exposure to light,
but it also suggest that other unknown molecular
mechanisms may be implicated. Overall, her work
demonstrates that the damaged retina does not
react the same way in the juvenile and adult animal.
PDF
version of the article
Fourth
Edition of the Vision Network Prize
Armando Bertone
I received my bachelor's degree
in psychology (Advanced Exprimental Psychology)
in 1996 at Concordia University. During this time,
I tool courses related to visual perception which
I found quite interesting. This led to the beginning
of my graduate studies, with Dr. Michael von Grunau
at Concordia University. With Dr. von Grunau,
I completed a master's degree in experimental
psychology in 1998. The project was related to
the perception of simple and complex dynamic stimuli
in the peripheral visual field, as well as maintained
attention during motion aftereffects.
In the autumn of 1998, I searched for a more applied
research project, I continued my academic career
at the University of Montreal in the Clinical
Neuropsychology program (research/intervention
option). During my clinical studies, I worked
in the laboratory of "Psychophysique et de
Perception Visuelle" at the School of Optometry,
under the supervision of Dr. Jocelyn Faubert.
With Dr. Faubert, I undertook studies on both
clinical and fundamental research projects (aging,
autism, fragile-X syndrome, etc.). At the School
of Optometry I was resposinle for the following
courses; "Psychophysique visuelle",
"Optométrie Pédiatrique",
and recently "Aspects Neuropsychologiques
en Optométrie".
In 2002, I obtained my second master's degree
(clinical), this allowed me to become a meber
of the order of Psychologist of Québec.
However, my interest for research was too strong,
and I spent the major part of my time doing research.
In 2004, I obtained my Ph.D. related to work on
the processing of dynamic information with autistics.
Presently, I am continuing my research in the
laboratory of Dr. Jocelyn Faubert as a post-doc.
Since last year, I am a part time member of the
faculty at Concordia University, and I still give
courses at the School of Optometry. The article
submitted for this prize was the third published
article, from our laboratory, on abnormal information
processing in autistics (the two other articles
were published in 2003 and 2004 in the Journal
of Cognitive Neurosciences and Neurology, respectively).
In the article, we present a new hypothesis concerning
abnormal information processing in autistics,
based on abnormal neuronal networks involved in
perception.
PDF
version of the article
Third
Edition of the Vision Network Prize
Frédéric Huppé
Gourges
L'The article submitted for the
Vision Network Prize is the result of research
conducted during my Master's degree.
Since I have begun my PhD, I have developped different
cortical injection systems and different analysis
methods (confocal micrscope, electronic micrscope,
stereological analysis). I have presented these
results at the annual meeting of the European
Federation of Neuroscience (FENS 2004), as well
as at the Society for Neuroscience (SFN 2004).
An article is in preparation based on these results.
For this work I have obtained a bursary from the
FCAR-FRSQ-Santé.
In the course of my Master's degree, I also participated
in a study that aimed to demonstrate the role
of retinal dopamine on contrast sensitivity of
lateral geniculate nucleus neurons (Coudé
et alé, in preparation). I will be second
author on this article, which should appear in
the next year. For the above described work, I
was financially supported by the FCAR-FRSQ-Santé.
During my Bachelor's degree, I worked from January
1998 to Septembre 1999 in the "Laboratoire
de Neuropsychologie Expérimentale Comparée
(LNEC) de l'Université du Québec
à Trois-Rivières (UQTR)", under
the direction of Roger Ward PhD. In particular,
I worked on different projects such as histochemistry
and volumetric studies of glycinergic cells of
the cochlear nucleus of C57BL6 and DBA2J mice.
I worked in this part time during the academic
year of 1998-1999 and full time for two summers.
In parralel to my fundamental research projects,
from January 1999 to Juin 1999, I also worked
with Lucie Godbout PhD in the " Laboratoire
de neuropsychologie expérimentale (volet
neuropsychologie humaine) de l'UQTR". I also
benefitted from an NSERC bursary for undergraduates.
From an academic point of view, I was a teaching
assistant for Dr. Michel Volle in the context
of the course "Les fontions nerveuses supérieures"
in the autumn of 1998, and "Psychophysiologie"
in the autumn of 1999 for Dr. Lucie Godbout. My
tasks were to present information to students
in teaching laboratories and general supervision
of students. During my Master's degree, I had
a course load in the School of Optometry "Sciences
de la vision: neurologie des mouvements visuels".
PDF
version of the article
Second
Edition of the Vision Network Prize
Martin Beauchamp
Le récipiendaire pour le
deuxième concours Prix Réseau Vision
est Martin Beauchamp.
La rétinopathie du prématuré
est une maladie obstructive proliférative
affectant nombre d'enfants prématurés
sur laquelle l'équipe du Dr Sylvain Chemtob
se penche depuis de nombreuses années.
Étudiant boursier dans le laboratoire du
Dr Chemtob au Centre de recherche de l'Hôpital
Ste-Justine de Montréal, Martin Beauchamp
en a fait son sujet de recherche.
En 1997, M. Beauchamp termine un baccalauréat
en sciences biologiques avant de s'intéresser
aux communications et à l'informatique,
intérêts qui l'ont mené à
l'obtention avec mention d'excellence d'un diplôme
de mineur en arts en sciences l'année suivante.
Recruté en janvier 1999 au sein de l'équipe
du Dr Sylvain Chemtob, M. Beauchamp est d'abord
boursier de la Fondation de l'Hôpital Ste-Justine
de 1999 à 2001. Sa contribution à
plusieurs publications dont deux en tant que premier
auteur et les nombreux prix qu'il reçoit
en 2000 (bourse d'études de la Fondation
de la recherche sur le monoxyde d'azote, prix
d'excellence : Journée de la recherche
du Centre de recherche de l'Hôpital Ste-Justine,
Trainee Travel Award de la American Federation
For Medical Research), lui permettent d'être
exempté du mémoire de maîtrise
et de passer directement au doctorat. En 2002,
il obtient une bourse de la Fondation des maladies
du cœur du Canada, bourse qu'il décline
au profit d'une plus prestigieuse, la bourse des
Instituts de recherche en santé du Canada
qui le soutient financièrement depuis ce
temps.
Que ce soit par la rédaction d'articles
scientifiques publiés dans des journaux
de haut calibre, la communication de résultats
de recherche à l'occasion de rencontres
internationales, l'élaboration de protocoles
pour l'expérimentation animale, la mise
sur pied et la direction d'un projet de recherche
pour des élèves stagiaires; toutes
ces activités lui ont permis de développer
un sens aigu des responsabilités, de l'organisation
et du leadership. Aujourd'hui, il termine sa formation
doctorale, fort de l'acquisition de nouvelles
techniques de laboratoire: pharmacologie in vivo
et ex vivo chez le rat adulte et le rat nouveau-né,
bio-informatique (prise de données et développement
d'applications biométriques, imagerie digitale),
microscopie en champ clair et fluorescence, histologie,
immunohistochimie et immunobuvardage de type western,
bases en culture cellulaire.
Tout au long de sa formation, M. Beauchamp a travaillé
à l'amélioration du modèle
animal de rétinopathie du prématuré
et a tenté de percer le mystère
de la dégénérescence microvasculaire
qui caractérise cette maladie. Les travaux
de M. Beauchamp ont permis de mettre en lumière
les circonstances contribuant au développement
de la maladie et l'importance de certaines substances
participant à la dégénérescence
de la microvasculature rétinienne immature.
PDF version of his article
Submission
for the Vision Network Prize
The deadline for submission for
the next Vision Network Prize is December 15
2007. The submitted article must be on a subject
related to vision health and have been published
in the last six months. The candidate must send
the following information to the secretariat:
1. A short biography (1 page)
2. A photography
3. The presneted article, of course!
An article can be presented more than once. The
criteria are the quality of the article as well
as the prestige of the journal it is published
in. All documents should be sent to the secretariat
of the network, in an electronic format, at réseau.vision@mcgill.ca. Do not hesitate
to contact us if you have any questions. The recipient
will receive a bursary of $500.
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