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Ultrastructural Analysis of Odontocete Cochlea

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Laboratori d’Aplicacions Bioacústiques Universitat Politècnica de Catalunya Ultrastructural analysis of Odontocete cochlea Thesis presented by MARIA MORELL YBARZ to obtain the Doctoral degree This thesis was supervised by: Dr. MICHEL ANDRÉ (Laboratory of Applied Bioacoustics, Technical University of Catalonia-Barcelona Tech) and Dr. MARC LENOIR (Inserm, U. 1051, Institut des Neurosciences de Montpellier) Vilanova i la Geltrú, May 4, 2012 1 Ultrastructural analysis of Odontocete cochlea Acknowlegdements ACKNOWLEDGEMENTS This dissertation is the result of many years of research at the Laboratory of Applied Bioacoustics (LAB, Technical University of Catalonia-Barcelona Tech) and it received the collaboration, help and effort of many people. First of all I would like to thank my supervisors, Michel André and Marc Lenoir for their unconditional support. Michel, thanks for giving me the opportunity to perform this research, standing by me when I needed, both personally and professionally, transmitting this passion, energy and encouragement with which you pervade those around you. Marc, thank you very much for everything you taught me so patiently, for your invaluable help and for being so positive about our work. This study and objectives were initiated by Michel André and Eduard Degollada. Eduard originally developed some of the protocols we used in this thesis. Thanks for all your ideas, advice and experience. I would also like to thank our colleagues and the stranding organizations who helped us in collecting the ears, especially Thierry Jauniaux (Université de Liège), Willy Dabin and Olivier Vancanneyt (Centre de Recherche sur les Mammifères Marins, Université de la Rochelle), Lidewij Wiersma, Lineke Begeman and Sjoukje Hiemstra (University of Utrecht), Iranzu Maestre and Pablo Cermeño (AMBAR), Marisa Ferreira (SPVS), Gema Hernández (University College Cork), Paco Toledano (PROMAR), Ángela Llavona, Josep Mª Alonso, Alfredo López and María Llarena (CEMMA), Beatriz González (Fundació CRAM), Encarna Gómez (Biologia Animal-Vertebrats, UB), Denik Ulqini (Universiteti i Shkodres), Mardik Leopold (IMARES), Kees C. J. Camphuysen (Royal NIOZ), Alexandre Dewez (GEFMA) and Martina Duras (University of Zagreb). I am also grateful to Dr Concepció Bru’s team from the Diagnostic Imaging Unit at the Hospital Clínic of Barcelona, especially Dr Carles Falcon, Dr Núria Bargalló, David Flores and Carles Reguera for their time, interest and dedication. I would like to thank Dr. Maria Cristina Manzanares and Eva Maria Sánchez, from the Unit of Anatomy and Human Embriology (Universitat de Barcelona) for all their support and disposition with the development of the experiment with Technovit. Part of the research of this thesis was developed at the Institut des Neurosciencies de Montpellier (INSERM, U. 1051) where I visited for over four months at different time. Each time I was there I felt like at home thanks to the researchers of the Pathophysiology and Therapy of Inner Ear team who always received me with open arms. I would like to thank Jérôme Bourien, Jing Wang, Rémy Pujol, Benjamin Delprat, Gastón Sendin, Lydie Fasquelle and Michel Eybalin for their help and advice in the interpretation of the results, Jean- Louis Pasquier for his help with iconography and the director Jean-Luc Puel for his interest and for inviting me in his unit, facilitating me any process that could allow me to make my visits easy. The technical assistance, adapting protocols for these new samples, was possible with the help of Sabine Ladrech, Florence François and Hassim Boukhaddaoui (INM), Chantal Cazevieille and Cécile Sanchez (CRIC), Jose-Manuel Fortuño (Institut de Ciències del Mar -CSIC) and Lluïsa Matas and Imma Arrom (Research Technical Service of the Universitat the Girona). My colleagues and friends from the LAB: Alex, Serge, Marta, Mike, Ludwig, Joan Vincent, Eric, Julien, Torbjörn and Pierre are who really have lived with me every day during the course of this thesis, have encouraged me when things were not going so well, we had good times together, and I learned a lot from them. I want to thank everyone, especially Mike for his invaluable help in this work with the statistical analysis and Serge for his help with programming in Matlab. 2 Ultrastructural analysis of Odontocete cochlea Acknowlegdements Finally, I thank all those who love me and who have been there for me, especially my parents, my brothers Joan and Xavier for their blind support from the very first day and above all Paulo, who has accompanied me with infinite patience throughout this journey. This study was funded by the BBVA Foundation, within the project Noise pollution effects on cetaceans, the Spanish Ministry of the Environment in the project eCREM, Effects and Control of Anthropogenic Noise in Marine Ecosystems (under contract 083/SDGTB / 2007) and AGAUR (Generalitat de Catalunya) fellowships. 3 Ultrastructural analysis of Odontocete cochlea Acknowlegdements AGRADECIMIENTOS Esta tesis es el fruto de varios años de investigación en el Laboratori d’Aplicacions Bioacústiques (LAB, Universitat Politècnica de Catalunya) y ha sido posible gracias a la ayuda, colaboración y esfuerzo de muchas personas. En primer lugar me gustaría agradecer a mis directores de tesis Michel André y Marc Lenoir por su apoyo incondicional. Michel, gracias por darme la oportunidad de llevar a cabo esta investigación, estar a mi lado cuando lo he necesitado, tanto a nivel personal como profesional, transmitirme esta pasión, energía y ánimos con que contagias a los que te rodean. Marc, muchas gracias por todo lo que me has enseñado con tanta paciencia, tu ayuda inestimable y ser tan positivo con nuestro trabajo. Este estudio y sus objetivos fueron iniciados por Michel André y Eduard Degollada. Eduard empezó a desarrolar algunos de los protocolos que hemos utilizado en esta tesis. Gracias por todas tus ideas, consejos y experiencia. También quisiera agradecer a todos nuestros compañeros de diferentes redes de varamientos que nos ayudaron a extraer y fijar los oídos que se han utilizado para este estudio, especialmente a Thierry Jauniaux (Université de Liège), Willy Dabin y Olivier Vancanneyt (Centre de Recherche sur les Mammifères Marins, Université de la Rochelle), Lidewij Wiersma, Lineke Begeman y Sjoukje Hiemstra (University of Utrecht), Iranzu Maestre y Pablo Cermeño (AMBAR), Marisa Ferreira (SPVS), Gema Hernández (University College Cork), Paco Toledano (PROMAR), Ángela Llavona, Josep Maria Alonso, Alfredo López y María Llarena (CEMMA), Beatriz González (Fundació CRAM), Encarna Gómez (Biologia Animal-Vertebrats, Universitat de Barcelona), Denik Ulqini (Universiteti i Shkodres), Mardik Leopold (IMARES), Kees C. J. Camphuysen (Royal NIOZ), Alexandre Dewez (GEFMA) y Martina Duras (University of Zagreb). Igualmente quisiera agradecer al equipo de la Dra. Concepció Bru de la Unidad de Diagnosis por Imagen del Hospital Clínic de Barcelona, sobre todo al Dr Carles Falcon, a la Dra Núria Bargalló, a Carles Reguera y a David Flores por su tiempo, interés y dedicación. A la Dra. Maria Cristina Manzanares y a Eva María Sánchez, de la Unidad de Anatomía y Embiología Humana (Universitat de Barcelona) quisiera dar las gracias por toda su disposición y apoyo en el desarrollo del experimento con Technovit. Parte de la investigación de esta tesis se ha desarrollado en el Institut des Neurosciencies de Montpellier (INSERM, U. 1051). He estado más de cuatro meses en diferentes periodos y cada vez que vuelvo me siento como en casa gracias a que los investigadores del equipo de Patofisiología y Terapia del Oído Interno me reciben con los brazos abiertos. Quisiera agradecer a Jérôme Bourien, Jing Wang, Rémy Pujol, Benjamin Delprat, Gastón Sendin, Lydie Fasquelle y Michel Eybalin por su ayuda y consejos en la interpretación de resultados, a Jean-Louis Pasquier por su ayuda con las imágenes y al director Jean-Luc Puel por su interés y haber facilitado cualquier proceso para que pudiera realizar esta estancia. La asistencia técnica, adaptando protocolos para estas nuevas muestras, ha sido posible gracias a la ayuda de Sabine Ladrech, Florence François y Hassim Boukhaddaoui (INM), Chantal Cazevieille y Cécile Sanchez (CRIC), José-Manuel Fortuño (Institut de Ciències del Mar-CSIC) y Lluïsa Matas y Imma Arrom (Servicio Técnico de investigación de la Universitat de Girona). Mis compañeros y amigos del LAB Alex, Serge, Marta, Mike, Ludwig, Joan Vicent, Eric, Julien, Torbjörn y Pierre son quienes realmente han convivido conmigo día a día durante el transcurso de esta tesis, me han animado cuando las cosas no salían bien, hemos pasado muy buenos momentos juntos, y he aprendido 4 Ultrastructural analysis of Odontocete cochlea Acknowlegdements mucho de todos ellos. Quiero daros las gracias a todos, especialmente a Mike por su inestimable ayuda en este trabajo con los análisis estadísticos y a Serge por su ayuda con la programación en Matlab. Finalmente agradezco a todos aquellos que me quieren y que han estado a mi lado, muy especialmente a mis padres, mis hermanos Joan y Xavier por su apoyo ciego en mi des del primer día y sobre todo a Paulo, quien con paciencia infinita me ha acompañado en todo este camino. Este trabajo ha sido financiado por la Fundación BBVA, dentro del proyecto Estudio de los efectos de la contaminación acústica marina sobre cetáceos, por el Ministerio de Medio Ambiente en el proyecto eCREM, Efectos y Control del Ruido Antropogénico en Ecosistemas Marinos (contrato 083/SDGTB/2007) y las becas de AGAUR (Generalitat de Catalunya).
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  • Anatomic Moment

    Anatomic Moment

    Anatomic Moment Hearing, I: The Cochlea David L. Daniels, Joel D. Swartz, H. Ric Harnsberger, John L. Ulmer, Katherine A. Shaffer, and Leighton Mark The purpose of the ear is to transform me- cochlear recess, which lies on the medial wall of chanical energy (sound) into electric energy. the vestibule (Fig 3). As these sound waves The external ear collects and directs the sound. enter the perilymph of the scala vestibuli, they The middle ear converts the sound to fluid mo- are transmitted through the vestibular mem- tion. The inner ear, specifically the cochlea, brane into the endolymph of the cochlear duct, transforms fluid motion into electric energy. causing displacement of the basilar membrane, The cochlea is a coiled structure consisting of which stimulates the hair cell receptors of the two and three quarter turns (Figs 1 and 2). If it organ of Corti (Figs 4–7) (4, 5). It is the move- were elongated, the cochlea would be approxi- ment of hair cells that generates the electric mately 30 mm in length. The fluid-filled spaces potentials that are converted into action poten- of the cochlea are comprised of three parallel tials in the auditory nerve fibers. The basilar canals: an outer scala vestibuli (ascending spi- membrane varies in width and tension from ral), an inner scala tympani (descending spi- base to apex. As a result, different portions of ral), and the central cochlear duct (scala media) the membrane respond to different auditory fre- (1–7). The scala vestibuli and scala tympani quencies (2, 5). These perilymphatic waves are contain perilymph, a substance similar in com- transmitted via the apex of the cochlea (helico- position to cerebrospinal fluid.