Search results for " Auditory"
showing 10 items of 240 documents
Localization of the two constitutively expressed nitric oxide synthase isoforms (nNOS and eNOS) in the same cell types in the saccule maculae of the …
2003
There is growing evidence for a nitric oxide/cyclic GMP pathway of signal transduction in the vestibular system. Recently, two isoforms of nitric oxide (NO) synthase (nNOS and eNOS) and NO itself have been identified at the light microscopic level in the vestibulocochlear system of mice using specific antibodies and a new fluorescence indicator. In order to acquire more information about signal transduction and tissue modulation in this neuroepithelium at the cellular and subcellular levels, ultrathin sections of London Resin White-embedded saccule maculae of the frog Rana pipiens were incubated with various concentrations of commercially available antibodies to nNOS and eNOS. The immunorea…
Evidence for a possible NOS back-up system in the organ of Corti of the guinea pig
2003
Recently, the two Ca(2+)/calmodulin-regulated nitric oxide synthase isoforms, nNOS and eNOS, and NO itself have been identified in the cochlea of vertebrates using specific antibodies and a new fluorescence indicator. In order to acquire more information about the quantitative and spatial distribution of these two constitutively expressed NOS isoforms (cNOS) in the organ of Corti at the cellular and subcelluar levels, ultrathin sections of London resin (LR) White-embedded cochleae of the guinea pig were incubated with various concentrations of commercially available antibodies to nNOS and eNOS. The immunoreactivity was visualized by a gold-labeled secondary antibody and the amount of the im…
Usher syndrome: molecular links of pathogenesis, proteins and pathways.
2006
Contains fulltext : 50437.pdf (Publisher’s version ) (Closed access) Usher syndrome is the most common form of deaf-blindness. The syndrome is both clinically and genetically heterogeneous, and to date, eight causative genes have been identified. The proteins encoded by these genes are part of a dynamic protein complex that is present in hair cells of the inner ear and in photoreceptor cells of the retina. The localization of the Usher proteins and the phenotype in animal models indicate that the Usher protein complex is essential in the morphogenesis of the stereocilia bundle in hair cells and in the calycal processes of photoreceptor cells. In addition, the Usher proteins are important in…
Genome-wide association analysis on normal hearing function identifies PCDH20 and SLC28A3 as candidates for hearing function and loss.
2015
Hearing loss and individual differences in normal hearing both have a substantial genetic basis. Although many new genes contributing to deafness have been identified, very little is known about genes/variants modulating the normal range of hearing ability. To fill this gap, we performed a two-stage meta-analysis on hearing thresholds (tested at 0.25, 0.5, 1, 2, 4, 8 kHz) and on pure-tone averages (low-, medium-and high-frequency thresholds grouped) in several isolated populations from Italy and Central Asia (total N = 2636). Here, we detected two genome-wide significant loci close to PCDH20 and SLC28A3 (top hits: rs78043697, P = 4.71E-10 and rs7032430, P = 2.39E-09, respectively). For both…
Synthetic individual binaural audio delivery by pinna image processing
2014
Purpose – The purpose of this paper is to present a system for customized binaural audio delivery based on the extraction of relevant features from a 2-D representation of the listener’s pinna. Design/methodology/approach – The most significant pinna contours are extracted by means of multi-flash imaging, and they provide values for the parameters of a structural head-related transfer function (HRTF) model. The HRTF model spatializes a given sound file according to the listener’s head orientation, tracked by sensor-equipped headphones, with respect to the virtual sound source. Findings – A preliminary localization test shows that the model is able to statically render the elevation of a vi…
Localization of Ca(2+)-stores and tissue compartments with a Ca(2+)-binding capacity in the organ of Corti of the guinea-pig by electron energy-loss …
1992
SUMMARY The addition of 10 mM CaCl2 to glutaraldehyde fixative leads to the formation of small electron-dense deposits in the organ of Corti of the guinea-pig. These precipitates are mainly attached to cell membranes in contact with different extracellular lymphatic fluids. A higher number of precipitates is localized in the acellular parts of tectorial and basilar membrane. Electron energy-loss spectroscopy (EELS) was used to determine the elemental composition of the deposits formed. The spectra showed a prominent signal at the Ca2+ L2,3 ionization edge. Oxygen could also be detected in all the precipitates analysed. EELS analysis of mitochondria of the inner and outer hair cells after co…
Possible Ca 2+ -dependent mechanism of apical outer hair cell modulation within the cochlea of the guinea pig
1998
Calcium ions were precipitated with potassium antimonate after injection of the inorganic calcium channel blocker MnCl2 or the inorganic potassium channel blockers BaCl2 or CsCl into the perilymph of the scala vestibuli of the guinea pig. The spatial distribution of the formed histochemical reaction products within the organ of Corti was studied by energy-filtering transmission-electron microscopy. Compared with untreated control ears, the number of the formed precipitates drastically increased at the extracellular side of the lamina reticularis after application of the various inorganic channel blockers. The apical side of the outer hair cells and the intervening Deiter cells were covered …
Vezatin, a novel transmembrane protein, bridges myosin VIIA to the cadherin-catenins complex
2000
International audience; Defects in myosin VIIA are responsible for deafness in the human and mouse. The role of this unconventional myosin in the sensory hair cells of the inner ear is not yet understood. Here we show that the C-terminal FERM domain of myosin VIIA binds to a novel transmembrane protein, vezatin, which we identi®ed by a yeast two-hybrid screen. Vezatin is a ubiquitous protein of adherens cell±cell junctions, where it interacts with both myosin VIIA and the cadherin±catenins complex. Its recruitment to adherens junctions implicates the C-terminal region of a-catenin. Taken together, these data suggest that myosin VIIA, anchored by vezatin to the cadherin±catenins complex, cre…
Histochemical localization of calcium ATPase in the cochlea of the guinea pig
1992
The activity of Ca(2+)-ATPase in the inner ear of the guinea pig was studied ultracytochemically by the lead citrate reaction. The electron-dense reaction products as an expression of Ca(2+)-ATPase activity were localized in endolymphatic cells of Reissner's membrane, in outer and inner hair cells and in some supporting cells. The main finding was the difference in the localization of Ca(2+)-ATPase in outer and inner hair cells. In the latter cells the activity sites were mainly intracellular and in apical membrane specializations, whereas in the outer hair cells the enzyme was localized in the apical membrane specializations and the basolateral plasma membrane.
Oscillatory Dynamics Underlying Perceptual Narrowing of Native Phoneme Mapping from 6 to 12 Months of Age
2016
During the first months of life, human infants process phonemic elements from all languages similarly. However, by 12 months of age, as language-specific phonemic maps are established, infants respond preferentially to their native language. This process, known as perceptual narrowing, supports neural representation and thus efficient processing of the distinctive phonemes within the sound environment. Although oscillatory mechanisms underlying processing of native and non-native phonemic contrasts were recently delineated in 6-month-old infants, the maturational trajectory of these mechanisms remained unclear. A group of typically developing infants born into monolingual English families, …