Associate Professor - Bobby R. Alford Dept. of Otolaryngology - Head and Neck Surgery Associate Professor - Department of Neuroscience M.D., University of Wisconsin - Madison, 1994 One Baylor Plaza, NA102 Houston, TX 77030 Telephone: 713-798-3200 - Fax: 713-798-5078 Email: jso@bcm.edu Website: www.bcm.edu/oto/jsolab/

Sensorineural hearing loss is a common disease and there are no effective treatments. While hearing aid technology continues to improve, they function basically to compress and amplify incoming sounds and cannot improve frequency discrimination. Cochlear implants are a valuable tool in alleviating deafness, but can not replicate normal hearing. Our laboratory is dedicated towards understanding mechanisms within the cochlea that underlie progressive sensorineural hearing loss and towards developing techniques to improve human hearing. We seek to better understand the relationship between the passive and active mechanical properties within the mammalian cochlea and the sensory hair cells as well as to develop techniques that can be used to modulate these properties. Our primary research techniques involve in vivo and in vitro studies in transgenic mice. Basilar membrane motion is measured using a laser doppler vibrometer. Cochlear function is assessed by measuring the compound action potential, the auditory evoked brainstem response, distortion product otoacoustic emissions, the cochlear microphonic, and the endocochlear potential. We measure changes in hair cell and spiral ganglion calcium using fluorescent indicators and two-photon microscopy. The physiology of single hair cells is assessed using the patch clamp technique. Additionally, histological analysis of the inner ear is performed using immunohistochemistry.

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Oghalai, J.S., A.A. Patel, T. Nakagawa, and W.E. Brownell, Fluorescence-imaged microdeformation of the outer hair cell lateral wall. J Neurosci, 1998. 18(1): p. 48-58.

Oghalai, J.S., T.D. Tran, R.M. Raphael, T. Nakagawa, and W.E. Brownell, Transverse and lateral mobility in outer hair cell lateral wall membranes. Hear Res, 1999. 135(1-2): p. 19-28.

Oghalai, J.S., H.B. Zhao, J.W. Kutz, and W.E. Brownell, Voltage- and tension-dependent lipid mobility in the outer hair cell plasma membrane. Science, 2000. 287(5453): p. 658-61.

Oghalai, J.S., Chlorpromazine inhibits cochlear function in guinea pigs. Hear Res, 2004. 198(1-2): p. 59-68.

Choi, C.H. and J.S. Oghalai, Predicting the effect of post-implant cochlear fibrosis on residual hearing. Hear Res, 2005. 205(1-2): p. 193-200.

Wenzel, G.I., B. Anvari, A. Mazhar, B. Pikkula, and J.S. Oghalai, Laser-induced collagen remodeling and deposition within the basilar membrane of the mouse cochlea. J Biomed Opt, 2007. 12(2): p. 021007.

Wenzel, G.I., A. Xia, E. Funk, M.B. Evans, D.J. Palmer, P. Ng, F.A. Pereira, and J.S. Oghalai, Helper-dependent adenovirus-mediated gene transfer into the adult mouse cochlea. Otol Neurotol, 2007. 28(8): p. 1100-8.

Xia, A., A.M. Visosky, J.H. Cho, M.J. Tsai, F.A. Pereira, and J.S. Oghalai, Altered traveling wave propagation and reduced endocochlear potential associated with cochlear dysplasia in the BETA2/NeuroD1 null mouse. J Assoc Res Otolaryngol, 2007. 8(4): p. 447-63.

Xia, A., J.R.A. Wooltorton, D.J. Palmer, P. Ng, F. Pereira, R.A. Eatock, and J.S. Oghalai, Prestin is required and essential for non-linear capacitance in outer hair cells. J Assoc Res Otolaryngol, in press.

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Assistant Professor (Tenure Track), Bobby R. Alford Department of Otolaryngology – Head and Neck Surgery, Baylor College of Medicine, Houston, TX (2003-pres.)

Secondary appointment, Department of Neuroscience, Baylor College of Medicine, Houston, TX (2008-pres.)

Adjunct Assistant Professor, Department of Bioengineering, Rice University, Houston, TX (2005-pres.)

Clinic Chief and Director of The Hearing Center at Texas Children's Hospital

The Dawn and Brook Lenfest Grant in Auditory Science (2004)

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• Alec Sevy
• Christopher Liu
• Simon Gao
• Tao Yuan

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Cochlear sensory epithelium cultures from prestin-null mice infected with helper-dependent adenovirus containing the genes for HA-prestin and GFP. (A) A confocal image of a whole-mount preparation under low magnification demonstrates that GFP was expressed primarily within the organ of Corti area (white asterisk and rectangles), the spiral limbus (blue asterisk), and the spiral ganglion area (yellow asterisk). (B) A representative confocal image under high magnification demonstrates transduction of OHCs and supporting cells. Some OHCs had bright GFP fluorescence (white arrow), some OHCs had low GFP fluorescence (blue arrow), and some OHCs had no GFP fluorescence (yellow arrow). Supporting cells were also transduced (arrowheads). (C) The number of GFP-positive and GFP-negative hair cells was determined in 35 images from 7 cochleae (representative areas counted are shown in A, rectangles). (D) A paraffin-embedded cross-section of a cultured preparation demonstrates that HA-prestin was expressed within the organ of Corti (OC, white asterisk), the spiral limbus (SPL, blue asterisk), and the spiral ganglion area (SG, yellow asterisk). These asterisks correspond to those in A. Myosin VIIa antibody labels the hair cells with green fluorescence. Scale bars: A, 200 µm; B, 50 µm; D, 100 µm.

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