Honors & News
March 28, 2016
Nam Research Article Recommended by F1000Prime
The research of Jong-Hoon Nam and his collaborators Anthony Peng and Anthony Ricci has been recommended in F1000Prime as being of special significance in its field by a F1000 faculty member. The research, published in June of 2015 is entitled,"Underestimated sensitivity of mammalian cochlear hair cells due to splay between stereociliary columns."
F1000Prime publishes recommendations of articles in biology and medicine from a faculty of around 5,000 scientists and clinical researchers and 5,000 more junior associate faculty. The service covers 40 disciplines and around 3,500 journals. Inclusion in F1000 prime indicates that an article has made an impact on the broad scientific areas of biology and medicine.
Read the abstract here:
Current-displacement (I-X) and the force-displacement (F-X) relationships characterize hair-cell mechano-transduction in the inner ear. A common technique for measuring these relationships is to deliver mechanical stimulations to individual hair bundles with microprobes and measure whole cell transduction currents through patch pipette electrodes at the basolateral membrane. The sensitivity of hair-cell mechano-transduction is determined by two fundamental biophysical properties of the mechano-transduction channel, the stiffness of the putative gating spring and the gating swing, which are derived from the I-X and F-X relationships. Although the hair-cell stereocilia in vivo deflect <100 nm even at high sound pressure levels, often it takes >500 nm of stereocilia displacement to saturate hair-cell mechano-transduction in experiments with individual hair cells in vitro. Despite such discrepancy between in vivo and in vitro data, key biophysical properties of hair-cell mechano-transduction to define the transduction sensitivity have been estimated from in vitro experiments. Using three-dimensional finite-element methods, we modeled an inner hair-cell and an outer hair-cell stereocilia bundle and simulated the effect of probe stimulation. Unlike the natural situation where the tectorial membrane stimulates hair-cell stereocilia evenly, probes deflect stereocilia unevenly. Because of uneven stimulation, 1) the operating range (the 10-90% width of the I-X relationship) increases by a factor of 2-8 depending on probe shapes, 2) the I-X relationship changes from a symmetric to an asymmetric function, and 3) the bundle stiffness is underestimated. Our results indicate that the generally accepted assumption of parallel stimulation leads to an overestimation of the gating swing and underestimation of the gating spring stiffness by an order of magnitude.
June 18, 2015
Jong-Hoon Nam Receives NIH R01 Grant
January 18, 2014
Dr. Jong-Hoon Nam Receives HSCCI Pilot Grant
Dr. Jong-Hoon Nam lab's research titled 'Computational analysis of micro-fluidic mechanotransduction in the mammalian cochlea' will be supported by the University of Rochester Office of the Provost and the School of Medicine and Dentistry Dean's office via the HSCCI (Health Sciences Center for Computational Innovation). The HSCCI supports health sciences research using high performance computational resources.
Dr. Nam's lab investigates the mechano-transduction of the inner ear — how the inner ear selects and amplifies external stimuli.
May 11, 2013
Yanju Liu Wins 1st Place in the CIRC (Center for Integrated Research Computing) Annual Poster Session
Yanju Liu won 1st place for her presentation in the CIRC (Center for Integrated Research Computing) Annual Poster Session that took place on Friday, May 10th. Congrats Yanju!
September 11, 2012
Dr. Jong-Hoon Nam Awarded NSF Grant
Jong-Hoon Nam, Ph.D., assistant professor of Biomedical Engineering and Mechanical Engineering, has been awarded a three year grant from the National Science Foundation (NSF). The objective of the project, entitled Multi-Scale Analysis of Mechanotransduction in the Organ of Corti, is to establish a coherent theory of how the organ of Corti (cochlear sensory epithelium) optimizes the force from the outer hair cells in order to magnify tiny vibrations of the basilar membrane.
With ME and BME professor, Sheryl Gracewski, Ph.D. as Co-PI, the research will take two innovative approaches. First, it will integrate cellular physiology and macro/micro mechanics of the cochlea. Second, computational and experimental models will be investigated in parallel to reduce the animal use while maximizing the research outcome. This will make a direct impact on understanding various hearing disorders. Besides hearing sensation, mechano-transduction plays a crucial role in other tissues such as muscle, bone and articular cartilage. Therefore, the findings of this research will advance the general understanding of mechano-sensation.
For more information please visit the Nam Lab.
- Underestimated sensitivity of mammalian cochlear hair cells due to splay between stereociliary columns.Biophys J. 108, 2633-47. (2015 Jun 02).
- Two-compartment passive frequency domain cochlea model allowing independent fluid coupling to the tectorial and basilar membranes.J Acoust Soc Am. 137, 1117-25. (2015 Mar 01).