University of Fribourg View Institution's Website 19 articles published in JoVE Biology A Cryoinjury Model for Studying Skeletal Muscle Regeneration of the Caudal Peduncle in Adult Zebrafish Hendrik Oudhoff1, Florian Baumgartner1, Anna Jaźwińska1 1Department of Biology, University of Fribourg This protocol describes a cryoinjury model to induce profound damage of several caudal myomeres in adult zebrafish. This method provides a new approach for studying skeletal muscle regeneration after severe loss of tissue in non-mammalian vertebrates. Bioengineering Cultivating a Three-dimensional Reconstructed Human Epidermis at a Large Scale Irini M. Dijkhoff1, Benedetta Petracca1,2, Roxane Prieux3, Giuseppe Valacchi3,4, Barbara Rothen-Rutishauser1, Marc Eeman2 1Adolphe Merkle Institute, University of Fribourg, 2Dow Silicones Belgium SRL, 3Department of Biomedical and Specialist Surgical Sciences, University of Ferrara, 4Department of Animal Sciences, Plants for Human Health Institute, North Carolina State University This protocol describes a straightforward method to cultivate three-dimensional reconstituted human epidermis in a reproducible and robust manner. Additionally, it characterizes the structure-function relationship of the epidermal barrier model. The biological responses of the reconstituted human epidermis upon proinflammatory stimuli are also presented. Biology Multicellular Human Alveolar Model Composed of Epithelial Cells and Primary Immune Cells for Hazard Assessment Hana Barosova*1, Barbara Drasler*1, Alke Petri-Fink1, Barbara Rothen-Rutishauser1 1Adolphe Merkle Institute, University of Fribourg Presented here is a protocol for primary human blood monocyte isolation as well as their differentiation into macrophages and dendritic cells and assembly with epithelial cells into a multicellular human lung model. Biological responses of cocultures composed of immune cells differentiated from either freshly isolated or thawed monocytes, upon exposure to proinflammatory stimuli, are compared. Biology Intrathoracic Injection for the Study of Adult Zebrafish Heart Thomas Bise1, Anna Jaźwińska1 1Department of Biology, University of Fribourg This method relies on the injection of 0.5−3 μL of solution into the thorax of adult zebrafish. The procedure efficiently delivers proteins and chemical compounds into the proximity of the zebrafish heart without damaging the organ. The approach is suitable for testing effects of exogenous factors on various tissues of the heart. Immunology and Infection Evaluation of Extracellular Vesicle Function During Malaria Infection María Andrea Hernández-Castañeda*1, Smart Mbagwu*1, Kehinde Adebayo Babatunde*1, Michael Walch1, Luis Filgueira1, Pierre-Yves Mantel1 1Department of Medicine, University of Fribourg In this work, we describe protocols to investigate the role of extracellular vesicles (EVs) released by Plasmodium falciparum infected erythrocytes. In particular, we focus on the interactions of EVs with endothelial cells. Medicine The Rabbit Model of Accelerated Atherosclerosis: A Methodological Perspective of the Iliac Artery Balloon Injury Manish Jain*1, Aurélien Frobert*1, Jérémy Valentin1, Stéphane Cook1, Marie-Noëlle Giraud1 1Cardiology, Department of Medicine, University of Fribourg Animal models of atherosclerosis are essential to understand the mechanism and to investigate newer approaches to prevent plaque development or rupture, a leading cause of death in the industrialized world. This protocol uses a combination of balloon injury and cholesterol rich diet to induce atherosclerotic plaques in rabbit iliac artery. Behavior Intracortical Inhibition Within the Primary Motor Cortex Can Be Modulated by Changing the Focus of Attention Yves-Alain Kuhn1, Martin Keller1, Jan Ruffieux1, Wolfgang Taube1 1Department of Medicine, Movement and Sport Sciences, University of Fribourg Using two different transcranial magnetic stimulation (TMS) protocols, this manuscript describes how to measure and compare cortical inhibition within the primary motor cortex when adopting different attentional foci. Neuroscience Non-invasive Assessment of Changes in Corticomotoneuronal Transmission in Humans Wolfgang Taube1, Christian Leukel1,2, Jens Bo Nielsen3,4, Jesper Lundbye-Jensen3,4 1Department of Medicine, Movement and Sport Science, University of Fribourg (Switzerland), 2Department of Sport Science, University of Freiburg (Germany), 3Department of Neuroscience and Pharmacology, University of Copenhagen, 4Department of Nutrition, Exercise and Sports, University of Copenhagen The aim of the present study was to assess changes in transmission at the corticomotoneuronal synapses in humans after repetitive transcranial magnetic stimulation. For this purpose, an electrophysiological method is introduced that allows assessment of pathway specific corticospinal transmission, i.e. differentiation of fast, direct corticospinal pathways from polysynaptic connections. Medicine Histological Quantification of Chronic Myocardial Infarct in Rats Jérémy Valentin1, Aurélien Frobert1, Guillaume Ajalbert1, Stéphane Cook1, Marie-Noëlle Giraud1 1Cardiology, Department of Medicine, University of Fribourg The post-mortem assessment of myocardial infarction (MI) in rodents is based on quantification of the infarct on stained heart sections. We describe an accurate method to quantify the infarct size using systematic sampling of harvested rat hearts from base to apex and image analyses of trichrome-stained histological sections. Behavior Force and Position Control in Humans - The Role of Augmented Feedback Benedikt Lauber1,2, Martin Keller2, Christian Leukel1,3, Albert Gollhofer1, Wolfgang Taube2 1Department of Sport Science, University of Freiburg, 2Department of Medicine, Movement and Sport Science, University of Fribourg, 3Bernsteincenter Freiburg Controlling an identical movement with position or force feedback results in different neural activation and motor behavior. This protocol describes how to investigate behavioral changes by looking at neuromuscular fatigue and how to evaluate motor cortical (inhibitory) activity using subthreshold TMS with respect to the interpretation of augmented feedback. Biology En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries Yi Yu1,2, Yuyan Xiong1,2, Jean-Pierre Montani2,3, Zhihong Yang1,2, Xiu-Fen Ming1,2 1Cardiovascular and Aging Research, Department of Medicine, Division of Physiology, Faculty of Science, University of Fribourg, 2Kidney Control of Homeostasis, Swiss National Centre of Competence in Research, 3System Physiology, Department of Medicine, Division of Physiology, Faculty of Science, University of Fribourg In this article we describe an adapted relatively easy method using the fluorescence dye diaminofluorescein-2 diacetate (DAF-2DA) and dihydroethidium (DHE) for en face simultaneous detection and visualization of intracellular nitric oxide (NO) and superoxide anion (O2.−) respectively, in freshly isolated intact aortas of an obesity mouse model. Behavior Simple and Computer-assisted Olfactory Testing for Mice Emanuele Brai1, Lavinia Alberi1 1Unit of Anatomy, Department of Medicine, University of Fribourg We present a simple and unbiased olfactory test in mice. With this protocol olfactory discrimination, preference, avoidance and sensitivity to a novel odor as compared to water can be assessed in single behavioral sessions. This method is indicated for a single experimenter and analysis is based on computer-assisted video processing. Biology A High Yield and Cost-efficient Expression System of Human Granzymes in Mammalian Cells Farokh Dotiwala1, Isabelle Fellay2, Luis Filgueira2, Denis Martinvalet3, Judy Lieberman1, Michael Walch2 1 We describe here a cost-efficient granzyme expression system using HEK293T cells that produces high yields of pure, fully glycosylated and enzymatically active protease. Biology Methylnitrosourea (MNU)-induced Retinal Degeneration and Regeneration in the Zebrafish: Histological and Functional Characteristics Ellinor Maurer1, Markus Tschopp1,2, Christoph Tappeiner1, Pauline Sallin3, Anna Jazwinska3, Volker Enzmann1 1Department of Ophthalmology, Inselspital, University of Bern, 2Department of Ophthalmology, University Hospital of Basel, 3Department of Biology, University of Fribourg Herein we demonstrate quantification of retinal de- and regeneration and its impact on visual function using N-methyl-N-nitrosourea in the adult zebrafish. Loss of visual acuity and decreased photoreceptor numbers were followed by proliferation in the inner nuclear layer. Complete morphological and functional regeneration occurred 30 days after the initial treatment. Bioengineering Cell-based Therapy for Heart Failure in Rat: Double Thoracotomy for Myocardial Infarction and Epicardial Implantation of Cells and Biomatrix Aurélien Frobert1, Jérémy Valentin1, Stéphane Cook1, Justine Lopes-Vicente1, Marie-Noëlle Giraud1 1Cardiology, Department of Medicine, University of Fribourg Implantation of a biograft to treat myocardial infarction induced by LAD ligation in a rodent model has conventionally required two open-heart surgeries. In order to reduce mortality and provide optimal conditions for fixation of solid and gelatinous biomatrices associated with cells, minimally invasive procedures have been developed. Neuroscience Light Preference Assay to Study Innate and Circadian Regulated Photobehavior in Drosophila Larvae Abud J. Farca Luna1, Alina M. H. J. von Essen1, Yves F. Widmer1, Simon G. Sprecher1 1Department of Biology, Institute of Cell and Developmental Biology, University of Fribourg Here we describe a light-dark preference test for Drosophila larva. This assay provides information about innate and circadian regulation of light sensing and processing photobehavior. Neuroscience Appetitive Associative Olfactory Learning in Drosophila Larvae Anthi A. Apostolopoulou1, Annekathrin Widmann1, Astrid Rohwedder1,2, Johanna E. Pfitzenmaier1, Andreas S. Thum1,2 1Department of Biology, University of Konstanz, 2Department of Biology, University of Fribourg Drosophila larvae are able to associate odor stimuli with gustatory reward. Here we describe a simple behavioral paradigm that allows the analysis of appetitive associative olfactory learning. Medicine Induction of Myocardial Infarction in Adult Zebrafish Using Cryoinjury Fabian Chablais1, Anna Jaźwińska1 1Department of Biology, Unit of Zoology, University of Fribourg, Fribourg, Switzerland Zebrafish represents a valuable model to study the mechanisms of heart regeneration in vertebrates. Here, we present a protocol for induction of a heart infarct in adult zebrafish using cryoinjury. This method results in massive cell death within 20% of the ventricular wall, similar to that observed in mammalian infarcts. Neuroscience Behavioral Assessment of Manual Dexterity in Non-Human Primates Eric Schmidlin*1, Mélanie Kaeser*1, Anne- Dominique Gindrat1, Julie Savidan1, Pauline Chatagny1, Simon Badoud1, Adjia Hamadjida1, Marie-Laure Beaud1, Thierry Wannier1, Abderraouf Belhaj-Saif1, Eric M. Rouiller1 1Department of Medicine, University of Fribourg As manual dexterity is a prerogative mainly of primates, behavioral tasks have been developed in macaque monkeys. Four reach and grasp prehension tasks, measuring hand manipulation ability and force, allow to establish functional recovery after a lesion of the central nervous system and to test the effect of a treatment.