Alfred L Nuttall
Oregon Health And Science University
Project start date: 1977-05-01
Project end date: 2013-01-31
Sponsored Links Excellgen http://Excellgen.com
CONTROL OF INNER EAR MICROCIRULATION
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
University Of Michigan At Ann Arbor 3003 South State Street, Room 1040 Ann Arbor, Mi 481091274
Grant 5R01DC000105-20 from National Institute On Deafness And Other Communication Disorders IRG: HAR
Abstract: This proposal seeks to define the mechanics of cochlear blood flow control. The proposal offers the hypothesis that nitric oxide (NO), a molecule with both vasoactive and neuroactive capacity, is one factor contributing to vascular tone in the cochlea. The sympathetic neural input is another factor, along with myogenic mechanisms. The study is in three parts. 1) Examines the systems that control cochlear blood flow in the normal cochlea. Responsiveness of smooth muscle is measured following manipulations of the sympathetic neural innervation and oxygen respiration. Measures of myogenic activity are accomplished by measuring the speed and amount of the blood flow change (by laser Doppler flowmetry) following compressions of the feeding arteries to the cochlea. 2) Measures the amount of sound-induced sensitivity loss in chronic experiments as a function of oxygen delivery to the cochlea. Oxygen concentration in the organ of Corti is measured using oxygen sensing microelectrodes. This is done in order to verify and study the exact oxygen deficit and the consequential energy shortfall in the cochlea. A "functional deficit model" is also explored, where a small topographic vascular lesion in the cochlea is created by light activation of the photothrombic agent, rose bengal. In both of these experiments, the relationship of the vascular change to the activity of the organ of Corti will be measured using the otoacoustic and cochlear microphonic distortion products. Direct observations of the vessels in the stria vascularis also will be made during sound stimulation. The velocity of the flowing blood in capillaries and the diameters of the capillaries will be determined. 3) determines the role of NO in cochlear blood flow control. First, the endogenous level of NO causing vasodilation of cochlear blood vessels will be determined by applying competitive blockers of NO synthase. The blockers will be given into the cochlea by perfusion and by systemic administration. The direct effect of NO on cochlear blood vessels will be measured by intravital microscopy. The study will also determine the toxicity of NO on sensory function. Taken as a whole, the aims of this proposal will establish the roles of intracochlear oxygenation, NO, and the sympathetic nervous system to the cochlea in establishing the basal cochlea blood flow and vascular reactivity.
Keywords: blood flow, cochlea, microcirculation, nitric oxide, oxygen consumption, vasodilation, amine oxidoreductase, cellular respiration, cochlear lesion, hearing, hypoxia, metabolism, noise biological effect, organ of Corti, sensorineural hearing loss, sympathetic nervous system, toxicology, vascular smooth muscle, cochlear microphonic potential, oxygen microelectrode, rose bengal, ultrasound blood flow measurement
Project start date: 1977-05-01
Project end date: 1997-03-31
5R01DC000105-20 (1995): $284279
5R01DC000105-19 (1994): $287983
CONTROL OF INNER EAR MICROCIRCULATION
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
University Of Michigan At Ann Arbor 3003 South State Street, Room 1040 Ann Arbor, Mi 481091274
Grant 5R01DC000105-17 from National Institute On Deafness And Other Communication Disorders IRG: HAR
Abstract: This investigation is concerned with the mechanisms that control blood flow in the cochlea, the degree or magnitude of such control, and the physical locations and effectors of the control. The nature of the blood-perilymph and blood-endolymph barriers are of additional interest as is the influence of the sympathetic nervous system on the cochlear blood supply. In-vivo blood flow velocity and blood vessel diameters are to be measured using light microscopic techniques. Analog and digital techniques will allow quantification of flow and vessel diameter changes for altered systemic blood pressure, cervical sympathetic ganglion electric stimulation, CO2 and O2 exposure, osmotic agents, and intense sound. Extensive use will be made of fluorescence microscopy using flurescein-isothiocyanate-labeled dextran and fluroescently labeled red blood cells. The dyes will be excited by xenon light epl-illumination or transillumination and recorded by an image intensified video camera and recording system. Quantitative analysis of cochlear vasculature will be accomplished by digital image processing techniques. Laser Doppler flowmetery will be used to determine cochlear blood flux changes and studies will be carried out to enlarge the understanding of the performance of this instrumentation. Expanded knowledge of laser-Doppler flowmetry will help bring this instrumentation closer to the possible future clinical application for the measurment of inner ear perfusion. Laser- Doppler flowmetry will be examined in experiments deriving comparative analytical measures of functional changes in cochlear blood flow which are assessed by hydrogen clearance (to measure regional blood flow), by oxygen sensitive microelectrodes (to measure intracochlear pO2), and from compound action potential responses (to test inner ear function). Autoregulation in the inner ear will be investigated by physically controlling systemic blood pressure with the aid of an extracorporeal blood recirculation system. The ultimate goal of the research is to determine the factors that influence cochlear microcirculation and the effect that circulation changes have on the inner ear. The studies will help us to understand normal homeostasis of the inner ear and clarify the role that microcirculation has in sudden deafness, fluctuant hearing, sound-induced hearing loss, and Meinere s disease.
Keywords: cochlea, endolymph, hemodynamics, homeostasis, labyrinth, microcirculation, perilymph, sympathetic ganglion, vascular endothelium permeability, Meniere s syndrome, acid base balance, action potential, carbon dioxide tension, cochlear microphonic potential, deafness, electrochemistry, oxygen tension, sympathetic nervous system, blood flow measurement, fluorescence microscopy, fluorescent dye /probe, guinea pig, heterodyning, histology, image processing, microelectrode, microscopy, scanning electron microscopy
Project start date: 1977-05-01
Project end date: 1993-03-31
5R01DC000105-27 (2001): $410661
5R01DC000105-26 (2000): $443462
5R01DC000105-25 (1999): $422798
5R01DC000105-24 (1998): $363021
5R01DC000105-32 (2006): $531454
5R01DC000105-31 (2005): $528531
Sponsored Links Excellgen http://Excellgen.com
5R01DC000105-30 (2004): $513286
5R01DC000105-29 (2003): $498480
5R01DC000105-35 (2010): $405273
CONTROL OF INNER EAR MICROCIRULATION
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
University Of Michigan At Ann Arbor 3003 South State Street, Room 1040 Ann Arbor, Mi 481091274
Grant 5R01DC000105-21 from National Institute On Deafness And Other Communication Disorders IRG: HAR
Project start date: 1977-05-01
Project end date: 1996-11-30
5R01DC000105-21 (1996): $299774
Grants awarded to Alfred L Nuttall
COCHLEAR BLOOD FLOW AND NEUROPEPTIDES
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
Oregon Health And Science University 3181 Sw Sam Jackson Pk Rd Portland, Or 972393098
Grant 5R03TW000502-03 from Fogarty International Center IRG: ICP
Abstract: This proposal seeks to define the mechanisms of cochlear blood flow control. The proposal offers the hypothesis that the sensory neurons and Substance P (SP) are important factors contributing to vascular tone in the cochlea. The study has four specific aims. 1) Characterize the vasodilatation effect of capsaicin-sensitive primary sensory neurons on cochlear blood flow by applying capsaicin through the anterior inferior cerebellar artery (AICA) and the round window membrane (RWM). This will demonstrate the significant role of capsaicin fibers as part of the cochlear blood flow regulation system. 2) Measure capsaicin-induced changes in the permeability of cochlear blood vessels. The permeability change will be revealed by intravenous infusion of colloidal silver, followed by serial sectioning of the cochlea. This study will demonstrate a role of this neuropeptide system in cochlear fluid homeostasis. 3a) Characterize the effect of SP neurotransmitter on cochlear blood flow and 3b) pharmacologically block the SP-based, capsaicin-induced cochlear vasodilatation. This will provide direct evidence for a significance of contribution of SP in the regulation of cochlear blood flow. 4a) Measure changes in cochlear vasodilatation produced by the capsaicin-sensitive neurons and neuropeptides in the hydropic guinea pig. The animal model of hydrops is a significant type of homeostatic pathology in the cochlea. This aim will determine if hydrops also alters the neuropeptide vasodilatative mechanisms. 4b) Measure the cochlear blood flow (CBF) change after capsaicin application in diabetic rat. The non-invasive laser Doppler flowmetry method for measurement of cochlear blood flow will be used in these experiments.
Keywords: blood flow, cochlea, neuropeptide, Meniere s disease, capsaicin, diabetes mellitus, disease model, ear pharmacology, homeostasis, microcirculation, neural information processing, neuron, neurotransmitter, protein structure /function, sensorimotor system, substance P, ultrasound blood flow measurement, vascular endothelium permeability, vasodilatation, guinea pig, intravenous administration, laboratory rat
Project start date: 1995-09-30
Project end date: 2000-09-29
5R03TW000502-03 (1997): $20000
CONTROL OF INNER EAR MICROCIRULATION
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
University Of Michigan At Ann Arbor
3003 South State Street, Room 1040
ann Arbor, Mi 481091274
Grant 2R01DC000105-18A1 from National Institute On Deafness And Other Communication Disorders IRG: HAR
Abstract: This proposal seeks to define the mechanics of cochlear blood flow control. The proposal offers the hypothesis that nitric oxide (NO), a molecule with both vasoactive and neuroactive capacity, is one factor contributing to vascular tone in the cochlea. The sympathetic neural input is another factor, along with myogenic mechanisms. The study is in three parts. 1) Examines the systems that control cochlear blood flow in the normal cochlea. Responsiveness of smooth muscle is measured following manipulations of the sympathetic neural innervation and oxygen respiration. Measures of myogenic activity are accomplished by measuring the speed and amount of the blood flow change (by laser Doppler flowmetry) following compressions of the feeding arteries to the cochlea. 2) Measures the amount of sound-induced sensitivity loss in chronic experiments as a function of oxygen delivery to the cochlea. Oxygen concentration in the organ of Corti is measured using oxygen sensing microelectrodes. This is done in order to verify and study the exact oxygen deficit and the consequential energy shortfall in the cochlea. A "functional deficit model" is also explored, where a small topographic vascular lesion in the cochlea is created by light activation of the photothrombic agent, rose bengal. In both of these experiments, the relationship of the vascular change to the activity of the organ of Corti will be measured using the otoacoustic and cochlear microphonic distortion products. Direct observations of the vessels in the stria vascularis also will be made during sound stimulation. The velocity of the flowing blood in capillaries and the diameters of the capillaries will be determined. 3) determines the role of NO in cochlear blood flow control. First, the endogenous level of NO causing vasodilation of cochlear blood vessels will be determined by applying competitive blockers of NO synthase. The blockers will be given into the cochlea by perfusion and by systemic administration. The direct effect of NO on cochlear blood vessels will be measured by intravital microscopy. The study will also determine the toxicity of NO on sensory function. Taken as a whole, the aims of this proposal will establish the roles of intracochlear oxygenation, NO, and the sympathetic nervous system to the cochlea in establishing the basal cochlea blood flow and vascular reactivity
Keywords: blood flow, cochlea, microcirculation, nitric oxide, oxygen consumption, vasodilation amine oxidoreductase, cellular respiration, cochlear lesion, hearing, hypoxia, metabolism, noise biological effect, organ of Corti, sensorineural hearing loss, sympathetic nervous system, toxicology, vascular smooth muscle cochlear microphonic potential, oxygen microelectrode, rose bengal, ultrasound blood flow measurement
Project start date: 1977-05-01
Project end date: 1997-03-31
2R01DC000105-18A1 (1993): $270349
EFFERENT INFLUENCE ON COCHLEAR MECHANOELECTRIC PHYSIOLOGY
Alfred L Nuttall, Director, Or Hear Resrch Cntr
Oregon Health And Science University, 3181 Sw Sam Jackson Pk Rd, Portland, Or 97239-3098
Grant 5R01DC000141-32 from National Institute On Deafness And Other Communication Disorders
Abstract: This proposal is concerned with the mechanical and electrical properties of cells in the organ of Corti and how those properties influence the ability of the organ to process sounds. In particular, the experiments are designed to determine how the outer hair cells (OHCs) function in vivo to control the vibration of the basilar membrane and cellular structure of the organ. It is thought that OHCs use their inherent motile ability to amplify sound-evoked vibration of the neurosensory structures in the cochlea. This process is called cochlear amplification. However, it is not known how OHCs accomplish this amplification, a property critical to normal hearing because it provides both for the great sensitivity of the ear and for the acuity needed to understand speech in a noisy environment. The amplifier mechanism must work within a system of mechanical and electrical filters. In Aim 1 we test the hypothesis that the stereocillia of OHCs act as a critical mechanical filter that has not yet been studied. The amplifier must also generate power and it is clear OHCs have cellular or subcellular motor activity that may provide the power. In Aim 2 we will determine whether cochlear amplification requires forces produced by the stereocilia (via so called fast adaptation) of OHCs or prestin motor molecules in the baso-lateral membrane of the OHC or both. The manipulation of endolymphatic calcium is key to the Aim 1 and 2 experiments. Finally, cochlear amplification can only come about with the proper (but as yet unknown) micromechanical motions of the system of cells that make up the organ of Corti. In Aim 3 we study the micro or cellular mechanics of the organ of Corti (in yivo) using custom designed measurement instrumentation based on low coherence optical interferometry. We investigate the mechanical processing of sound that occurs with activity of the OHCs and the resulting stimulation of the stereocilia of inner hair cells. Knowledge of OHCs and organ of Corti mechanics is essential to our understanding of the normal and pathophysiologial function of the cochlea. Data derived in these studies are critically needed for appropriate mathematical modeling of the inner ear and in turn such models provide the only way to completely understand its complex mechanics
Keywords: Acoustic; Acoustics; Amplifiers; Apical; Auditory Canal, External; Basilar Membrane; Blood Coagulation Factor IV; Body Tissues; Ca++ element; Calcium; Cavia; Cell Components; Cell Function; Cell Locomotion; Cell Migration; Cell Movement; Cell Process; Cell Structure; Cell membrane; Cell physiology; Cells; Cellular Function; Cellular Migration; Cellular Physiology; Cellular Process; Cellular Structures; Chloride; Chloride Ion; Chlorides; Cl- element; Coagulation Factor IV; Cochlea; Cochlear Organ; Cochlear structure; Complex; Corti Cell; Cortis Organ; Custom; Cytoplasmic Membrane; Data; Dependence; Doppler OCT; Ear; Ear Canal; Ear structure; Ear, Internal; Endolymph; Environment; External Acoustic Meatus; External auditory canal structure; Factor IV; Frequencies (time pattern); Frequency; Goals; Guinea Pigs; Hair; Hair Cells; Hair Cells, Inner; Hair Cells, Outer; Hearing; Inner Hair Cells; Instrumentation, Other; Interferometry; Investigators; Knowledge; Laboratories; Labyrinth; Lateral; Learning; Locomotor Activity; Mammals, Guinea Pigs; Maps; Math Models; Measurement; Measures; Mechanics; Membrane; Modeling; Motility; Motility, Cellular; Motion; Motor; Motor Activity; Movement; OCT Tomography; Optical Coherence Tomography; Optics; Organ; Organ of Corti; Organ of Corti structure; Otoacoustic Emissions, Spontaneous; Outer Hair Cell of the Organ of the Corti; Outer Hair Cells; Pattern; Phase; Physiology; Plasma Membrane; Preparation; Pres protein, rat; Process; Production; Programs (PT); Programs [Publication Type]; Property; Property, LOINC Axis 2; Receptor Protein; Relative; Relative (related person); Research Personnel; Researchers; Role; Solutions; Sound; Sound - physical agent; Speech; Speed; Speed (motion); Spiral Organ; Spiral Organ of Corti; Spontaneous Otoacoustic Emissions; Stereocilium; Stereovillus; Structure; Subcellular Process; System; System, LOINC Axis 4; Technology; Testing; Tissues; Tomography, Optical Coherence; V (voltage); Vibration; Vibration - physical agent; Work; base; body movement; cell motility; design; designing; driving force; ear hair cell; electrical property; experiment; experimental research; experimental study; extracellular; hearing perception; in vivo; inner ear; instrumentation; mathematical model; mathematical modeling; membrane structure; otoacoustic emission; plasmalemma; prestin; prestin (motor protein), rat; prestin protein, rat; programs; rat Pres protein; receptor; research study; response; social role; sound; sound perception; theories; vibration; voltage
Project start date: 1979-04-01
Project end date: 2012-01-31
Budget start date: 1-FEB-2010
Budget end date: 31-JAN-2011
5R01DC000141-32 (2010): $530854
2R01DC000141-29A1 (2007): $462156
CONTROL OF INNER EAR MICROCIRCULATION
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
Otolaryngology Head & Neck Surgeryoregon Health & Science University
3181 Sw Sam Jackson Pk Rd
portland, Or 972393098
Grant 3R01DC000105-25S1 from National Institute On Deafness And Other Communication Disorders IRG: HAR
Abstract: The roles of reactive oxygen species (ROS), nitric oxide (NO), and cochlear blood flow in cochlear function and in sound-induced hearing loss will be examined with a combination of experimental manipulations and biochemical and physiological measurements. In Aim 1, generation of ROS during and after ischemia will be evaluated by manipulating glutathione levels, measuring NO levels, blocking NO synthesis, and chelating iron (to diminish production of hydroxyl radical). In Aim 2, roles of these factors in sound-induced hearing loss will be evaluated by examining the effects of similar manipulations on short-term and long-term hearing loss after high-level exposure to sound, and by hemodilution to alter blood flow and oxygen delivery. In Aim 3, a newly-discovered trigeminal C-fiber innervation of the cochlear vasculature will be studied by electrical stimulation, observing the effects of on blood flow and cochlear vascular permeability, and by tract-tracing to establish more completely its anatomical path
Keywords: ischemia, labyrinth, microcirculation, nitric oxide, noise induced deafness C fiber, blood flow, enzyme activity, glutathione, hydroxyl radical, iron, neuroanatomy, neuroregulation, nitric oxide synthase, trigeminal nerve (V), vascular endothelium permeability, vascular smooth muscle nervous control electrostimulus, guinea pig
Project start date: 1977-05-01
Project end date: 2002-08-31
3R01DC000105-25S1 (2000): $19999
2R01DC000105-23 (1997): $354272
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
Oregon Health And Science University 3181 Sw Sam Jackson Pk Rd Portland, Or 972393098
Grant 1P30DC005983-019001 from National Institute On Deafness And Other Communication Disorders IRG: ZDC1
Abstract: The Oregon Hearing Core (OHCC) Bioengineering Core (Core 1) will support six of the OHCC users and four collaborating investigators. The purpose of the Bioengineering core is to provide engineering and software expertise and to provide electrophysiological characterization of certain animals needed in projects of the users. In engineer will design and build custom electronic and mechanical devices that solve experimental and data acquisition problems. A computer programmer will write computer software (e.g. a Lab View virtual instrument) to address the experimental needs of the users. Projects undertaken by engineer and programmer will extend the funded work of the core users and stimulate collaborative studies between users. The programmer will help create common data bases that would allow sharing of experimental data among users. In addition, an electrophysiology technician will be available to measure (in mice, guinea pigs or gerbils) auditory brainstem responses, cochlear compound action potentials, distortion product otoacoustic emissions, and endocochlear potentials. An important activity of the technician will be to characterize the functional status of the cochlea in mutant mice produced by the OHCC Mouse Molecular Genetics Core. As for the engineer and programmer, the technician will work with Core users to extend work on supported R01s and enhance collaborative studies.
Keywords: bioengineering /biomedical engineering, biomedical equipment development, biomedical facility, computer system design /evaluation, electrophysiology, brain stem, cochlea, cochlear microphonic potential, computer program /software, hearing, information system, otoacoustic emission, gerbil /jird, guinea pig, laboratory mouse
Project start date: 2003-03-01
Project end date: 2008-02-28
Mechanics Of Hearing Meeting 2005
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
Oregon Health And Science University 3181 Sw Sam Jackson Pk Rd Portland, Or 972393098
Grant 1R13DC007582-01 from National Institute On Deafness And Other Communication Disorders IRG: CDRC
Abstract: The Ninth Mechanics of Hearing Workshop - Auditory Mechanisms Processes and Models - The Benson Hotel, Portland Oregon, July 23-28, 2005 - This proposal requests support for a workshop to bring together active senior experimentalists and theoreticians working in hearing mechanics in diverse species, along with students and junior investigators entering this field of research. The purpose of the workshop is to discuss, at length and in depth, the most recent theoretical and experimental work in the field, together with the currently important issues and controversies. One primary goal of the workshop is to advance the understanding of the peripheral mechanisms of hearing. An increased understanding of auditory mechanics will aid in our understanding of, and future treatment of hearing impairment. The primary objective is to promote strong interaction and connections between theoretical and experimental scientists. To ensure involvement of all attendees in each interest area, the number of orally presented papers will be limited to approximately 50 to avoid parallel sessions. This number will allow ample representation of different opinions while still being conducive to free discussion. Poster sessions will permit individuals who are not selected for oral presentations to present their data and ideas. Written copies of the papers will be circulated to registrants of the meeting a month before the meeting and the proceedings of the meeting will be published immediately afterward. This rapid publication time scale will be accomplished by requiring authors to submit manuscripts electronically at the time of registration or at the meeting itself. The secondary goal is to introduce mechanics-of-hearing scientists to the idea and feasibility of science outreach. To this end, the workshop will have a scientific outreach component where one of the plenary speakers will provide a lecture for high school students. In addition, attendees will receive information and experience in how to be proactive in the area of public education for hearing science.
Keywords: hearing, meeting /conference /symposium, travel
Project start date: 2005-02-01
Project end date: 2006-01-31
1R13DC007582-01 (2005): $32939
COCHLEAR BLOOD FLOW AND NEUROPEPTIDES
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
Oregon Health And Science University 3181 Sw Sam Jackson Pk Rd Portland, Or 972393098
Grant 5R03TW000502-06 from Fogarty International Center IRG: ICP
Abstract: The migraine related inner ear symptoms for phonopobia , tinnitus, hearing fluctuation, hearing loss, and increased noise sensitivity provide evidence for a possible neurological substrate connecting basilar artery migraine and cochlear pathophysiological mechanisms. Recently we have identified a previously unreported sensory innervation of the cochlear blood vessels originating from the trigeminal ganglia. We have shown that this sensory innervation has a significant effect on cochlear blood flow (CBF) in both normal and pathological conditions (e.g., in the animal model of endolymphatic hydrops, one of the symptoms of Meniere s disease). This proposal seeks to further define the anatomical basis and mechanisms of the trigemino-sensory network around the vertebrovasilar and cochlear vascular system. The proposal offers the hypothesis that the trigemino-sensory system and its related neuropeptide system are important factors contributing to basilar migraine and vascular homeostasis of the cochlea. The study has three specific aims. Aim 1. To establish if there is a physiological basis for the cochlear symptoms in basilar artery migraine headache. Positive results will confirm a common functional basis for basilar migraine and cochlear symptoms, the basis could be neurogenic inflammation. Aim 2. To demonstrate if vanilloid receptor (VR1) and substance P (SP) are co-localized around cochlear blood vessels, the basilar artery and its related branches. Positive immunocytochemical results will demonstrate (a) network of the VR1 and (b) SP co-labeled primary sensory neurons around the basilar artery; anterior inferior cerebellar artery (AICA), spiral modiolar artery (SMA) and radial artery; (c), Capsaicin will cause a significant reduction in the density of labeled sensory fibers. Aim 3. To determine the vasoregulatory disturbance of the trigemino-sensory neurons in endolymphatic hydrops. In this study positive results will demonstrate that endolymphatic hydrops causes a reduction in the stimulated trigeminal ganglion induced CBF change. The studies of the proposal will help clarify how trigemino-sensory neurons regulate the vertebro-basilar vascular system and cochlear fluid balance under normal and pathological conditions.
Keywords: blood flow, cochlea, neuropeptide, neurophysiology, Meniere s disease, capsaicin, cooperative study, disease /disorder model, ear pharmacology, ganglion, homeostasis, migraine, neural information processing, neuroanatomy, neuron, neuroregulation, protein structure function, sensorimotor system, substance P, trigeminal nerve, ultrasound blood flow measurement, vascular endothelium permeability, vasodilatation, guinea pig, immunocytochemistry
Project start date: 1995-09-30
Project end date: 2005-07-31
5R03TW000502-06 (2002): $37317
Sponsored Links Excellgen http://Excellgen.com
5R03TW000502-05 (2001): $37395
2R03TW000502-04 (2000): $37395
Low Optical Coherence Interferometry For The Cochlea
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
Oregon Health And Science University 3181 Sw Sam Jackson Pk Rd Portland, Or 972393098
Grant 1R55DC006273-01A1 from National Institute On Deafness And Other Communication Disorders IRG: AUD
Abstract: The major goal in this proposal is to develop and instrument to measure the vibration of the organ of Corti in the living guinea pig. The instrument will use the principles of optical coherence topography (OCT) and low optical coherence interferometer to visualize the basilar membrane and the internal structures of the organ and to measure their vibratory displacements induced by sound stimulation of the ear, respectively. The OCT interferometer will utilize light from two different super luminescent diodes coupled into a common optical fiber, allowing simultaneous measurement of the vibratory displacement of the basilar membrane and the reticular lamina components of the organ of Corti. The first two aims of the proposal are 1) to develop a dual source (two channels) OCT interferometer for measurements at a single location in the organ and 2) to develop a scanning OCT interferometer to measure organ of Corti motion in three dimensions. OCT interferometer will have the advantage of not requiring any reflective objects (such as mirrors or beads) to be placed on the ear tissues and will have high optical spatial resolution (particularly in the z direction along the optical axis) allowing accurate magnitude and phase measurements of organ of Corti tissue vibration. The third aim is to use the OCT instrument to measure the three-dimensional vibration pattern of the basilar membrane and reticular lamina in the guinea pig. The data will give critical new insight into the micro mechanical motion of the organ of Corti and on the mechanism of the cochlear amplification process whereby outer hair cells are thought to be actively enhancing organ of Corti motion.
Keywords: auditory stimulus, biomedical equipment development, interferometry, optical tomography, organ of Corti, vibration, biomechanics, ear hair cell, fiber optics, bioimaging /biomedical imaging, guinea pig
Project start date: 2004-06-01
Project end date: 2004-12-17
1R55DC006273-01A1 (2004): $100000
5R01DC006273-03 (2007): $258818
5R01DC006273-02 (2006): $192455
1R01DC006273-01A2 (2005): $279016
Alfred L Nuttall, Director, Or Hear Resrch Cntr
Oregon Health And Science University, 3181 Sw Sam Jackson Pk Rd, Portland, Or 97239-3098
Abstract: The Bioengineering Core will support all P30 investigators and collaborating investigators. The purpose of this Core is to provide engineering and software expertise needed in the projects of the users and to maintain the OHRC sound-exposure and auditory-brainstem-response (ABR) facilities. The P30 engineer will design and build custom electronic and mechanical devices that solve experimental and data acquisition problems. The P30 computer programmer will write computer software (e.g., a Lab- View virtual instruments) to address the experimental needs of the users. Projects undertaken by the engineer and programmer will extend the funded work of the Core users and stimulate collaborative studies between users. The P30 staff will help create common databases that would allow sharing of experimental data among users and enable more secure data backup. Core staff also advise faculty on specification and purchase of instrumentation and software
Keywords: Address; Animals; Articulation; Auditory; Auditory Brainstem Responses; Biomedical Engineering; Calibration; Collaborations; Computer Programs; Computer Software Development; Computer Software Engineering; Computer software; Computers; Custom; Data; Data Banks; Data Bases; Databank, Electronic; Databanks; Database, Electronic; Databases; Devices; Electronics; Engineering; Engineering, Software; Engineerings; Faculty; Fostering; Funding; Gene Targeting; Goals; Individual; Instrumentation, Other; Investigators; Joints; Laboratories; Mammals, Mice; Mechanics; Mice; Murine; Mus; P-30; P-30 Protein; P30; P30 Protein; Productivity; Programs (PT); Programs [Publication Type]; R01 Mechanism; R01 Program; RPG; Research Grants; Research Personnel; Research Project Grants; Research Projects; Research Projects, R-Series; Research Resources; Researchers; Resources; Secure; Software; Software Engineering; Solutions; Sound; Sound - physical agent; System; System, LOINC Axis 4; Targetings, Gene; Testing; Time; Training; Update; Work; Writing; bioengineering; bioengineering/biomedical engineering; clinical data repository; clinical data warehouse; computer program/software; data acquisition; data repository; design; designing; experiment; experimental research; experimental study; improved; instrument; instrumentation; interest; programs; ranpirnase; relational database; research study; sound; success; virtual
Budget start date: 1-AUG-2010
Budget end date: 31-JUL-2011
5P30DC005983-08_9001 (2010): $247663
Efferent Influence--Cochlear Mechanoelectric Physiology
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
Oregon Health And Science University 3181 Sw Sam Jackson Pk Rd Portland, Or 972393098
Grant 5R01DC000141-28 from National Institute On Deafness And Other Communication Disorders IRG: ZRG1
Abstract: Sound stimulation of the cochlea leads to mechanoelectric activity in the organ of Corti. Outer hair cells play a central but little understood role in the normal cochlear response to sound. Furthermore, outer hair cell (OHC) activity is controlled in an almost completely unknown way by a complex innervation from the olivocochlear efferent fibers. This proposal seeks to add to our understanding of organ of Corti function by examining its mechanoelectric responses to sound and to efferent nerve electric stimulation. Organ of Corti response will be measured as gross cochlear potentials, ear canal otoacoustic responses, receptor potentials of hair cells and, most importantly, as velocity and displacement responses measured from various locations in the organ of Corti. Each of these measurements provides a different viewpoint on the performance of inner and OHCs acting together in vivo. This proposal applies a dramatic new technology for the study of cellular vibration in the inner ear. Laser feedback interferometry (LFI) is a method with sufficient sensitivity to register the vibration of nearly transparent cellular elements. LFI applied through a microscope allows one to focus a laser beam onto the different cellular structures in the organ of Corti. A detailed study of the traveling wave will provide an important empirical base for theoretical studies of organ of Corti function by providing information on mechanical displacements of its cellular structures. This understanding is necessary in order to determine how mechanical energy stimulates the inner and OHCs. LFI microscopy can provide the cellular displacement measurements needed to determine how OHCs serve as motile elements in this system. Finally, with this proposal we are beginning the study of the physiology of the supporting cells of the organ of Corti. Until recently, supporting cells were thought to be largely passive elements, only lending structural support to the system. There is mounting evidence now that Deiters cells are motile and dynamic structures. We will measure the changes in organ of Corti vibration following types of stimulation that lead to changes in Deiters cell morphology. Taken together, the studies of this proposal will provide an understanding of how OHCs generate high frequency selectivity and sensitivity in the normal inner ear, the function of the olivocochlear efferent system and the structural dynamics of supporting cells in the organ of Corti.
Keywords: auditory stimulus, biomechanics, cochlea, efferent nerve, electrophysiology, olivocochlear bundle, organ of Corti, acetylcholine, calcium flux, cell motility, ear hair cell, electrostimulus, membrane potential, otoacoustic emission, salicylate, fluorescent dye /probe, guinea pig, interferometry
Project start date: 1979-04-01
Project end date: 2007-02-11
5R01DC000141-28 (2006): $602535
5R01DC000141-27 (2005): $600320
5R01DC000141-26 (2004): $582888
Sponsored Links Excellgen http://Excellgen.com
5R01DC000141-25 (2003): $565976
3R01DC000141-22S1 (2000): $19499
5R01DC000141-23 (2001): $488715
5R01DC000141-22 (2000): $469984
5R01DC000141-21 (1999): $452498
5R01DC000141-20 (1998): $443825
5R01DC000141-19 (1997): $406646
Control Of Inner Ear Microcirculation
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
Oregon Health And Science University 3181 Sw Sam Jackson Pk Rd Portland, Or 972393098
Grant 2R01DC000105-28 from National Institute On Deafness And Other Communication Disorders IRG: ZRG1
Abstract: Nitric oxide (NO) is a major signaling molecule in biological systems. It serves in normal physiology as a vasodilator and a regulator of cellular processes including energy metabolism. It is also involved in tissue pathology through the damage caused by nitrogen related reactive oxygen species (ROS). The abundant NO synthase (NOS) found in the organ of Corti suggests a role for NO in the mechanical or electrical function of the organ. The NOS found in the stria vascularis and endothelial cells of blood vessels could be important to blood vessel permeability as well as vasodilation. The state of the cochlear blood flow (CBF) and the microcirculation in the cochlea is of critical importance to hearing. It is known that age, drugs and loud sound cause changes in cochlear circulation but it is not know whether these changes are a cause of hearing loss or perhaps accelerate declining hearing. This proposal is designed to evaluate the normal physiology of NO generation in the cochlea and the pathological consequences of ROS formation. Aim 1 has the goal of evaluating whether NO produced in the organ of Corti affects the sensitivity and mechanical responses of the organ. Electrophysiological and mechanical measurements of organ of Corti responses to sound while blocking or enhancing NO levels in the cochlea accomplish this. Aim 2 has the goals of determining whether NO caused vasodilation of CBF reduces the damaging effects of loud sound exposure; whether NO prevents abnormal vascular permeability of the CBF; and how hypoxia alters the cellular biology of cochlear vascular smooth muscle. Mutant mice, deficient in endothelial cell NOS, will be used in part of this work. In Aim 3 it will be determined if an inducible form of NOS (iNOS) is responsible for loss of sensitivity and of sensory cells as a result of noise exposure. These studies will use the mutant mouse lacking iNOS as well as the experimental approach of pharmacological inhibition of iNOS. The work will also determine the amount and cellular locations of nitrogen related ROS. By correlation of the cellular ROS levels with the early expression of stress proteins and subsequent cell death, it will be possible learn the importance of NO in the pathological process of noise-induced hearing loss. The long term goals of this work are to learn how cochlear microcirculation and the NO biochemistry can be treated to prevent noise induced and age-related hearing loss .
Keywords: hearing, labyrinth, microcirculation, nitric oxide, noise induced deafness, C fiber, blood flow, cochlea, enzyme activity, free radical oxygen, ischemia, neuroanatomy, neuroregulation, nitric oxide synthase, noise, organ of Corti, vasodilation, electrical measurement, electrophysiology, electrostimulus, fluorescence microscopy, guinea pig, laboratory mouse, transgenic animal
Project start date: 1977-05-01
Project end date: 2007-08-31
2R01DC000105-28 (2002): $477639
3-D OPTICAL IMAGING OF THE IN VIVO ORGAN OF CORTI MOTION AT A SUB-NANOMETER SCALE
Alfred L Nuttall, Director, Or Hear Resrch Cntr
Oregon Health And Science University, 3181 Sw Sam Jackson Pk Rd, Portland, Or 97239-3098
Grant 1R01DC010399-01 from National Institute On Deafness And Other Communication Disorders
Abstract: Low optical coherence tomography (OCT) has been used to image biological tissue and is the theoretical basis of microscopes that are commercially available to image the lens and cellular structures of the human eye. Interferometers based on OCT have not been produced but have unique properties useful for vibration measurements of the tissues and cells of the inner ear. We propose to develop an OCT interferometer that has the ability to both image the living organ of Corti and measure its cellular motion in 3-dimensions down to a vibration as small as 0.1 nm. The basic concept of OCT interferometry has already proven usefulness for the micromechanics of the organ of Corti. This proposal implements technical advances that permit needed higher resolution that enables determination of the direction and phase of the organ displacement vector at the cellular level. The instrument will have an imaging and vibration resolution of about 3 cubic micrometers through the use of a femtosecond pulsed laser. This is accomplished by incorporation of a novel phase-sensitive OCT approach allowing the instrument to be used to test the hypothesis that the tectorial membrane is mechanically resonant in the lateral (radial) direction. Knowledge of the in vivo mechanics of the tectorial membrane, including resonance, will set to rest a quarter century of conjecture on how the organ achieves the efficient mechanical stimulation of the inner ear hair cell stereocilia and the subsequent remarkable sensitivity of mammalian hearing. The discoveries of cochlear mechanics that this optical coherence tomography (OCT) instrument will allow are critical to the understanding of normal hearing, the mechanisms of the otoacoustic emissions that are used as clinical audiometric tests and the defects in hearing caused by loud sound and by deafness genes. The OCT method we will develop also has other applications for human health in Otolaryngology OCT could image the vibration of the middle ear structures as an audiometric method, measure blood flow in the human inner ear to classify which patients with sudden deafness have deficient flow or measure and map blood flow in a microvascular skin flap to improve the viability of flaps
Keywords: 3-D; 3-Dimensional; 3D image; Algorithms; Audiogram; Audiometric Test; Audiometry; Basilar Membrane; Biological; Blood flow; Body Tissues; Cell Communication and Signaling; Cell Components; Cell Signaling; Cell Structure; Cells; Cellular Structures; Clinical; Cochlea; Cochlear Organ; Cochlear structure; Computer Programs; Computer software; Corti Cell; Cortis Organ; Coupling; Data; Deafness; Defect; Dimensions; Doppler OCT; Ear; Ear structure; Ear, Internal; Electromagnetic, Laser; Eye; Eyeball; Flaps; Frequencies (time pattern); Frequency; Funding; Genes; Goals; Hair Cells; Health; Hearing; Human; Human Resources; Human, General; Illumination; Image; Images, 3-D; Interferometry; Intracellular Communication and Signaling; Island Flaps; Knowledge; Labyrinth; Lasers; Lateral; Life; Lighting; Location; Man (Taxonomy); Man, Modern; Manpower; Maps; Measurement; Measures; Mechanical Stimulation; Mechanics; Methods; Microscope; Motion; Noise; OCT Tomography; Optical Coherence Tomography; Optics; Organ; Organ of Corti; Organ of Corti structure; Oto/Rhino/Laryngology; Otoacoustic Emissions, Spontaneous; Otolaryngology; Patients; Phase; Physiologic pulse; Problem Solving; Process; Programs (PT); Programs [Publication Type]; Property; Property, LOINC Axis 2; Pulse; Radial; Radiation, Laser; Resolution; Rest; Sampling; Scala Tympani; Signal Transduction; Signal Transduction Systems; Signaling; Skin; Software; Sound; Sound - physical agent; Source; Spiral Organ; Spiral Organ of Corti; Spontaneous Otoacoustic Emissions; Stereocilium; Stereovillus; Structure; Structure of tectorial membrane; Sudden Deafness; Surface; Surgical Flaps; System; System, LOINC Axis 4; Tectorial Membrane; Testing; Three-Dimensional Image; Time; Tissues; Tomography, Optical Coherence; Travel; Tympanus, Scala; Vibration; Vibration - physical agent; base; biological signal transduction; computer program/software; develop software; developing computer software; ear hair cell; hearing perception; imaging; improved; in vivo; inner ear; instrument; interest; lens; middle ear; nano; nano meter scale; nano meter sized; nano scale; nanometer scale; nanometer sized; nanoscale; new technology; novel; optic imaging; optical imaging; otoacoustic emission; otorhinolaryngology; personnel; programs; public health relevance; response; software development; sound; sound perception; tectorial membrane; user-friendly; vector; vibration
Relevance: Narrative The discoveries of cochlear mechanics that this optical coherence tomography (OCT) instrument will allow are critical to the understanding of normal hearing, the mechanisms of the otoacoustic emissions that are used as clinical audiometric tests and the defects in hearing caused by loud sound and by deafness genes. The OCT method we will develop also has other applications for human health in Otolaryngology: OCT could image the vibration of the middle ear structures as an audiometric method, measure blood flow in the human inner ear to classify which patients with sudden deafness have deficient flow or measure and map blood flow in a microvascular skin flap to improve the viability of flaps
Project start date: 2009-12-01
Project end date: 2013-11-30
Budget start date: 1-DEC-2009
Budget end date: 30-NOV-2010
PFA/PA: PA-07-070
1R01DC010399-01 (2010): $377597
EFFERENT INFLUENCE--COCHLEAR MECHANOELECTRIC PHYSIOLOGY
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
University Of Michigan At Ann Arbor 3003 South State Street, Room 1040 Ann Arbor, Mi 481091274
Grant 5R01DC000141-15 from National Institute On Deafness And Other Communication Disorders IRG: HAR
Abstract: Adapted from s .) This proposal seeks to add to our knowledge concerning organ of Corti function by examining its mechanoelectric responses to sound using four distinct, but linked measurement approaches; gross cochlear potentials, ear canal otoacoustic responses, intracellular hair cell receptor potentials, and most importantly, basilar membrane motion. Each of these provides a different viewpoint on the performance of inner and outer hair cells. The detailed motion pattern of the basilar membrane will be studied first, using a new method for this purpose. A new and detailed view of the traveling wave pattern will provide an important empirical base for future theoretical models of the organ of Corti function and establish a point of experimental departure to measure olivocochlear efferent activity. Natural, sound evoked, activation of efferents as well as electrical activation will be studied. Ear canal otoacoustic changes during efferent activation will be directly compared to basilar membrane motion changes. This comparison will reveal some mechanical aspects of neurally controlled outer hair cell performance. The role of the efferent system to protect OHCs from the damaging effects of loud sound will be studied, as will how efferent activity can improve our ability to detect and code sounds in the presence of masking noises. The investigators will also study the physiology of the higher brain stem levels of the descending efferent pathways. Electric current stimulation of areas of the inferior colliculus will be used to activate this system, leading not only to new information on the descending pathways proper but perhaps also on the unknown physiology of the "lateral" efferent fibers which terminate on the peripheral processes of afferent neurons.
Keywords: auditory stimulus, biological signal transduction, cochlear microphonic potential, ear hair cell, efferent nerve, mechanoreceptor, organ of Corti, receptor, stimulus /response, visceral afferent nerve, auditory feedback, auditory threshold shift, cat, electrical potential, electrostimulus, evoked potential, hearing test, inferior colliculus, loudness, neural information processing, noise biological effect, perceptual masking, chinchilla, computer processing of laboratory data, electrophoresis, electrophysiology, guinea pig, histochemistry /cytochemistry
Project start date: 1979-04-01
Project end date: 1995-01-31
5R01DC000141-15 (1994): $323221
Sponsored Links Excellgen http://Excellgen.com
EFFERENT INFLUENCE ON COCHLEAR MECHANOELECTRIC PHYSIOLOG
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
University Of Michigan At Ann Arbor 3003 South State Street, Room 1040 Ann Arbor, Mi 481091274
Grant 5R01DC000141-14 from National Institute On Deafness And Other Communication Disorders IRG: HAR
Abstract: Adapted from s .) This proposal seeks to add to our knowledge concerning organ of Corti function by examining its mechanoelectric responses to sound using four distinct, but linked measurement approaches; gross cochlear potentials, ear canal otoacoustic responses, intracellular hair cell receptor potentials, and most importantly, basilar membrane motion. Each of these provides a different viewpoint on the performance of inner and outer hair cells. The detailed motion pattern of the basilar membrane will be studied first, using a new method for this purpose. A new and detailed view of the traveling wave pattern will provide an important empirical base for future theoretical models of the organ of Corti function and establish a point of experimental departure to measure olivocochlear efferent activity. Natural, sound evoked, activation of efferents as well as electrical activation will be studied. Ear canal otoacoustic changes during efferent activation will be directly compared to basilar membrane motion changes. This comparison will reveal some mechanical aspects of neurally controlled outer hair cell performance. The role of the efferent system to protect OHCs from the damaging effects of loud sound will be studied, as will how efferent activity can improve our ability to detect and code sounds in the presence of masking noises. The investigators will also study the physiology of the higher brain stem levels of the descending efferent pathways. Electric current stimulation of areas of the inferior colliculus will be used to activate this system, leading not only to new information on the descending pathways proper but perhaps also on the unknown physiology of the "lateral" efferent fibers which terminate on the peripheral processes of afferent neurons.
Keywords: auditory stimulus, biological signal transduction, cochlear microphonic potential, ear hair cell, efferent nerve, mechanoreceptor, organ of Corti, receptor, stimulus /response, visceral afferent nerve, auditory feedback, auditory threshold shift, cat, electrical potential, electrostimulus, evoked potential, hearing test, inferior colliculus, loudness, neural information processing, noise biological effect, perceptual masking, chinchilla, computer processing of laboratory data, electrophoresis, electrophysiology, guinea pig, histochemistry /cytochemistry
Project start date: 1979-04-01
Project end date: 1995-01-31
5R01DC000141-14 (1993): $308025
5R01DC000141-13 (1992): $305057
Alfred L Nuttall
Oregon Health And Science University
Project start date: 2009-12-01
Project end date: 2013-11-30
3-D OPTICAL IMAGING OF THE IN VIVO ORGAN OF CORTI MOTION AT A SUB-NANOMETER SCALE
Alfred L Nuttall
Department/ Educational Institution Type:
Grant 5R01DC010399-02 from National Institute On Deafness And Other Communication Disorders
Keywords: 3-D; 3-Dimensional; 3D image; Algorithms; Audiogram; Audiometric Test; Audiometry; base; Basilar Membrane; Biological; biological signal transduction; Blood flow; Body Tissues; Cell Communication and Signaling; Cell Components; Cell Signaling; Cell Structure; Cells; Cellular Structures; Clinical; Cochlea; Cochlear Organ; Cochlear structure; computer program/software; Computer Programs; Computer software; Corti Cell; Cortis Organ; Coupling; Data; Deafness; Defect; develop software; developing computer software; Dimensions; Doppler OCT; Ear; ear hair cell; Ear structure; Ear, Internal; Electromagnetic, Laser; Eye; Eyeball; Flaps; Frequencies (time pattern); Frequency; Funding; Genes; Goals; Hair Cells; Health; Hearing; hearing perception; Human; Human Resources; Human, General; Illumination; Image; Images, 3-D; imaging; improved; in vivo; inner ear; instrument; interest; Interferometry; Intracellular Communication and Signaling; Island Flaps; Knowledge; Labyrinth; Lasers; Lateral; lens; Life; Lighting; Location; Man (Taxonomy); Man, Modern; Manpower; Maps; Measurement; Measures; Mechanical Stimulation; Mechanics; Methods; Microscope; middle ear; Motion; nano; nano meter scale; nano meter sized; nano scale; nanometer scale; nanometer sized; nanoscale; new technology; Noise; novel; OCT Tomography; optic imaging; Optical Coherence Tomography; optical imaging; Optics; Organ; Organ of Corti; Organ of Corti structure; Oto/Rhino/Laryngology; otoacoustic emission; Otoacoustic Emissions, Spontaneous; Otolaryngology; otorhinolaryngology; Patients; personnel; Phase; Physiologic pulse; Problem Solving; Process; programs; Programs (PT); Programs [Publication Type]; Property; Property, LOINC Axis 2; public health relevance; Pulse; Radial; Radiation, Laser; Resolution; response; Rest; Sampling; Scala Tympani; Signal Transduction; Signal Transduction Systems; Signaling; Skin; Software; software development; sound; Sound; Sound - physical agent; sound perception; Source; Spiral Organ; Spiral Organ of Corti; Spontaneous Otoacoustic Emissions; Stereocilium; Stereovillus; Structure; Structure of tectorial membrane; Sudden Deafness; Surface; Surgical Flaps; System; System, LOINC Axis 4; Tectorial Membrane; tectorial membrane; Testing; Three-Dimensional Image; Time; Tissues; Tomography, Optical Coherence; Travel; Tympanus, Scala; user-friendly; vector; Vibration; vibration; Vibration - physical agent
Relevance: Narrative The discoveries of cochlear mechanics that this optical coherence tomography (OCT) instrument will allow are critical to the understanding of normal hearing, the mechanisms of the otoacoustic emissions that are used as clinical audiometric tests and the defects in hearing caused by loud sound and by deafness genes. The OCT method we will develop also has other applications for human health in Otolaryngology: OCT could image the vibration of the middle ear structures as an audiometric method, measure blood flow in the human inner ear to classify which patients with sudden deafness have deficient flow or measure and map blood flow in a microvascular skin flap to improve the viability of flaps
Project start date: 2009-12-01
Project end date: 2013-11-30
Budget start date: 1-DEC-2010
Budget end date: 30-NOV-2011
PFA/PA: PA-07-070
5R01DC010399-02 (2011): $385831
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
Oregon Health And Science University 3181 Sw Sam Jackson Pk Rd Portland, Or 972393098
Grant 5P30DC005983-046660 from National Institute On Deafness And Other Communication Disorders IRG: ZDC1
Project start date: 2006-04-01
Project end date: 2008-03-31
EFFERENT INFLUENCE--COCHLEAR MECHANOELECTRIC PHYSIOLOGY
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
University Of Michigan At Ann Arbor 3003 South State Street, Room 1040 Ann Arbor, Mi 481091274
Grant 5R01DC000141-17 from National Institute On Deafness And Other Communication Disorders IRG: HAR
Project start date: 1979-04-01
Project end date: 1996-11-30
5R01DC000141-17 (1996): $409934
COCHLEAR BLOOD FLOW AND NEUROPEPTIDES
Alfred L Nuttall, Professor Of Otolaryngology, Director Or
Otolaryngology Head & Neck Surgeryoregon Health & Science University
3181 Sw Sam Jackson Pk Rd
portland, Or 972393098
Grant 7R03TW000502-02 from Fogarty International Center IRG: ICP
Project start date: 1995-09-30
Project end date: 1998-09-29
7R03TW000502-02 (1996): $20000