Distinct capacity for differentiation to inner ear cell types by progenitor cells of the cochlea and vestibular organs

PubMed Central

McLean, Will J.; McLean, Dalton T.; Eatock, Ruth Anne

2016-01-01

Disorders of hearing and balance are most commonly associated with damage to cochlear and vestibular hair cells or neurons. Although these cells are not capable of spontaneous regeneration, progenitor cells in the hearing and balance organs of the neonatal mammalian inner ear have the capacity to generate new hair cells after damage. To investigate whether these cells are restricted in their differentiation capacity, we assessed the phenotypes of differentiated progenitor cells isolated from three compartments of the mouse inner ear – the vestibular and cochlear sensory epithelia and the spiral ganglion – by measuring electrophysiological properties and gene expression. Lgr5+ progenitor cells from the sensory epithelia gave rise to hair cell-like cells, but not neurons or glial cells. Newly created hair cell-like cells had hair bundle proteins, synaptic proteins and membrane proteins characteristic of the compartment of origin. PLP1+ glial cells from the spiral ganglion were identified as neural progenitors, which gave rise to neurons, astrocytes and oligodendrocytes, but not hair cells. Thus, distinct progenitor populations from the neonatal inner ear differentiate to cell types associated with their organ of origin. PMID:27789624

Integrated annotation and analysis of in situ hybridization images using the ImAnno system: application to the ear and sensory organs of the fetal mouse.

PubMed

Romand, Raymond; Ripp, Raymond; Poidevin, Laetitia; Boeglin, Marcel; Geffers, Lars; Dollé, Pascal; Poch, Olivier

2015-01-01

An in situ hybridization (ISH) study was performed on 2000 murine genes representing around 10% of the protein-coding genes present in the mouse genome using data generated by the EURExpress consortium. This study was carried out in 25 tissues of late gestation embryos (E14.5), with a special emphasis on the developing ear and on five distinct developing sensory organs, including the cochlea, the vestibular receptors, the sensory retina, the olfactory organ, and the vibrissae follicles. The results obtained from an analysis of more than 11,000 micrographs have been integrated in a newly developed knowledgebase, called ImAnno. In addition to managing the multilevel micrograph annotations performed by human experts, ImAnno provides public access to various integrated databases and tools. Thus, it facilitates the analysis of complex ISH gene expression patterns, as well as functional annotation and interaction of gene sets. It also provides direct links to human pathways and diseases. Hierarchical clustering of expression patterns in the 25 tissues revealed three main branches corresponding to tissues with common functions and/or embryonic origins. To illustrate the integrative power of ImAnno, we explored the expression, function and disease traits of the sensory epithelia of the five presumptive sensory organs. The study identified 623 genes (out of 2000) concomitantly expressed in the five embryonic epithelia, among which many (∼12%) were involved in human disorders. Finally, various multilevel interaction networks were characterized, highlighting differential functional enrichments of directly or indirectly interacting genes. These analyses exemplify an under-represention of "sensory" functions in the sensory gene set suggests that E14.5 is a pivotal stage between the developmental stage and the functional phase that will be fully reached only after birth.

Sox2 and Jagged1 Expression in Normal and Drug-Damaged Adult Mouse Inner Ear

PubMed Central

Campbell, Sean; Taylor, Ruth R.; Forge, Andrew; Hume, Clifford R.

2007-01-01

Inner ear hair cells detect environmental signals associated with hearing, balance, and body orientation. In humans and other mammals, significant hair cell loss leads to irreversible hearing and balance deficits, whereas hair cell loss in nonmammalian vertebrates is repaired by the spontaneous generation of replacement hair cells. Research in mammalian hair cell regeneration is hampered by the lack of in vivo damage models for the adult mouse inner ear and the paucity of cell-type-specific markers for non-sensory cells within the sensory receptor epithelia. The present study delineates a protocol to drug damage the adult mouse auditory epithelium (organ of Corti) in situ and uses this protocol to investigate Sox2 and Jagged1 expression in damaged inner ear sensory epithelia. In other tissues, the transcription factor Sox2 and a ligand member of the Notch signaling pathway, Jagged1, are involved in regenerative processes. Both are involved in early inner ear development and are expressed in developing support cells, but little is known about their expressions in the adult. We describe a nonsurgical technique for inducing hair cell damage in adult mouse organ of Corti by a single high-dose injection of the aminoglycoside kanamycin followed by a single injection of the loop diuretic furosemide. This drug combination causes the rapid death of outer hair cells throughout the cochlea. Using immunocytochemical techniques, Sox2 is shown to be expressed specifically in support cells in normal adult mouse inner ear and is not affected by drug damage. Sox2 is absent from auditory hair cells, but is expressed in a subset of vestibular hair cells. Double-labeling experiments with Sox2 and calbindin suggest Sox2-positive hair cells are Type II. Jagged1 is also expressed in support cells in the adult ear and is not affected by drug damage. Sox2 and Jagged1 may be involved in the maintenance of support cells in adult mouse inner ear. PMID:18157569

Vestibular sensory functional status of cochlear implanted ears versus non-implanted ears in bilateral profound deaf adults.

PubMed

Cozma, Romică Sebastian; Dima-Cozma, Lucia Corina; Rădulescu, Luminiţa Mihaela; Hera, Maria Cristina; Mârţu, Cristian; Olariu, Raluca; Cobzeanu, Bogdan Mihail; Bitere, Oana Roxana; Cobzeanu, Mihail Dan

2018-01-01

Patients with hearing loss who underwent cochlear implantation can present symptomatic or asymptomatic vestibular damages earlier or later after the surgery. The vestibular permanent lesions could be acute, produced by surgical trauma or could be progressive due to local morphological changes made by the presence of the portelectrode in the inner ear (fibrosis related, ossification, basilar membrane distortion, endolymphatic hydrops). Besides histopathological findings in inner ear of cochlear implanted patients, the vestibular permanent damages could be found by assessment of clinical vestibular status. This study reports the sensorial vestibular functional findings for adults in cochlear implanted ears related to the electrode insertion type (cochleostomy or round window approach) and comparing to non-implanted deaf ears. A total of 20 adult patients with 32 cochlear implanted ears (12 patients with binaural cochlear implant and eight with monoaural) were selected for postoperatory vestibular examination by cervical and ocular vestibular myogenic potentials and vestibular caloric tests. The same tests were made for a control group of 22 non-implanted deaf ears. Functional testing results were reported related to the electrode insertion approach. For the cochleostomy group, we found different deficits: in 40% for saccular function, 44% for utricular function, and 12% horizontal canal dysfunction. In round window group, the deficit was present in 14.29% for saccular function, 28.57% for utricular function, and 28.58% for horizontal canal. In 46.88% of implanted ears, the vestibular function was completely preserved on all tested sensors. In conclusion, the vestibular functional status after inner ear surgery presents sensorial damages in 53.12% ears compare with the vestibular dysfunction existing in 50% of deaf non-operated ears. Round window insertion allows for better conservation of the vestibular function.

Inner Ear Morphology in the Atlantic Molly Poecilia mexicana—First Detailed Microanatomical Study of the Inner Ear of a Cyprinodontiform Species

PubMed Central

Schulz-Mirbach, Tanja; Heß, Martin; Plath, Martin

2011-01-01

Background Fishes show an amazing diversity in hearing abilities, inner ear structures, and otolith morphology. Inner ear morphology, however, has not yet been investigated in detail in any member of the diverse order Cyprinodontiformes. We, therefore, studied the inner ear of the cyprinodontiform freshwater fish Poecilia mexicana by analyzing the position of otoliths in situ, investigating the 3D structure of sensory epithelia, and examining the orientation patterns of ciliary bundles of the sensory hair cells, while combining μ-CT analyses, scanning electron microscopy, and immunocytochemical methods. P. mexicana occurs in different ecotypes, enabling us to study the intra-specific variability (on a qualitative basis) of fish from regular surface streams, and the Cueva del Azufre, a sulfidic cave in southern Mexico. Results The inner ear of Poecilia mexicana displays a combination of several remarkable features. The utricle is connected rostrally instead of dorso-rostrally to the saccule, and the macula sacculi, therefore, is very close to the utricle. Moreover, the macula sacculi possesses dorsal and ventral bulges. The two studied ecotypes of P. mexicana showed variation mainly in the shape and curvature of the macula lagenae, in the curvature of the macula sacculi, and in the thickness of the otolithic membrane. Conclusions Our study for the first time provides detailed insights into the auditory periphery of a cyprinodontiform inner ear and thus serves a basis—especially with regard to the application of 3D techniques—for further research on structure-function relationships of inner ears within the species-rich order Cyprinodontiformes. We suggest that other poeciliid taxa, or even other non-poeciliid cyprinodontiforms, may display similar inner ear morphologies as described here. PMID:22110746

Inner ear morphology in the Atlantic molly Poecilia mexicana--first detailed microanatomical study of the inner ear of a cyprinodontiform species.

PubMed

Schulz-Mirbach, Tanja; Hess, Martin; Plath, Martin

2011-01-01

Fishes show an amazing diversity in hearing abilities, inner ear structures, and otolith morphology. Inner ear morphology, however, has not yet been investigated in detail in any member of the diverse order Cyprinodontiformes. We, therefore, studied the inner ear of the cyprinodontiform freshwater fish Poecilia mexicana by analyzing the position of otoliths in situ, investigating the 3D structure of sensory epithelia, and examining the orientation patterns of ciliary bundles of the sensory hair cells, while combining μ-CT analyses, scanning electron microscopy, and immunocytochemical methods. P. mexicana occurs in different ecotypes, enabling us to study the intra-specific variability (on a qualitative basis) of fish from regular surface streams, and the Cueva del Azufre, a sulfidic cave in southern Mexico. The inner ear of Poecilia mexicana displays a combination of several remarkable features. The utricle is connected rostrally instead of dorso-rostrally to the saccule, and the macula sacculi, therefore, is very close to the utricle. Moreover, the macula sacculi possesses dorsal and ventral bulges. The two studied ecotypes of P. mexicana showed variation mainly in the shape and curvature of the macula lagenae, in the curvature of the macula sacculi, and in the thickness of the otolithic membrane. Our study for the first time provides detailed insights into the auditory periphery of a cyprinodontiform inner ear and thus serves a basis--especially with regard to the application of 3D techniques--for further research on structure-function relationships of inner ears within the species-rich order Cyprinodontiformes. We suggest that other poeciliid taxa, or even other non-poeciliid cyprinodontiforms, may display similar inner ear morphologies as described here.

Shaping of inner ear sensory organs through antagonistic interactions between Notch signalling and Lmx1a

PubMed Central

Mann, Zoe F; Chen, Ziqi; Chrysostomou, Elena; Żak, Magdalena; Kang, Miso; Canden, Elachumee

2017-01-01

The mechanisms of formation of the distinct sensory organs of the inner ear and the non-sensory domains that separate them are still unclear. Here, we show that several sensory patches arise by progressive segregation from a common prosensory domain in the embryonic chicken and mouse otocyst. This process is regulated by mutually antagonistic signals: Notch signalling and Lmx1a. Notch-mediated lateral induction promotes prosensory fate. Some of the early Notch-active cells, however, are normally diverted from this fate and increasing lateral induction produces misshapen or fused sensory organs in the chick. Conversely Lmx1a (or cLmx1b in the chick) allows sensory organ segregation by antagonizing lateral induction and promoting commitment to the non-sensory fate. Our findings highlight the dynamic nature of sensory patch formation and the labile character of the sensory-competent progenitors, which could have facilitated the emergence of new inner ear organs and their functional diversification in the course of evolution. PMID:29199954

[Immunocytochemical study of cholinergic innervation in the neurosensory epithelia of human vestibule].

PubMed

Kong, W; Hussl, B; Schrott-Fischer, A

1998-02-01

To investigate the cholinergic innervation of the neurosensory epithelia of human vestibule. A modified preembedding immunostaining technique for immunoelectronmicroscopy was applied to this study. A polyclonal antibody to choline acetyltransferase (ChAT) was used as the marker of cholinergic fibers. ChAT-immunoreactive products were restricted to the nerve fibers and terminals which were rich in synaptic vesicles. The ChAT-immunoreactive fibers synaps with afferent chalice as well as with type II sensory hair cells. This study demonstrates that cholinergic fibers innervate the neurosensory epithelia of human vestible. The cholinergic fibers of human vestibular sensory epithelia belong to the vestibular efferent system.

Scanning Thin-Sheet Laser Imaging Microscopy Elucidates Details on Mouse Ear Development

PubMed Central

Kopecky, Benjamin; Johnson, Shane; Schmitz, Heather; Santi, Peter; Fritzsch, Bernd

2016-01-01

Background The mammalian inner ear is transformed from a flat placode into a three-dimensional (3D) structure with six sensory epithelia that allow for the perception of sound and both linear and angular acceleration. While hearing and balance problems are typically considered to be adult onset diseases, they may arise as a developmental perturbation to the developing ear. Future prevention of hearing or balance loss requires an understanding of how closely genetic mutations in model organisms reflect the human case, necessitating an objective multidimensional comparison of mouse ears with human ears that have comparable mutations in the same gene. Results Here, we present improved 3D analyses of normal murine ears during embryonic development using optical sections obtained through Thin-Sheet Laser Imaging Microscopy. We chronicle the transformation of an undifferentiated otic vesicle between mouse embryonic day 11.5 to a fully differentiated inner ear at postnatal day 15. Conclusions Our analysis of ear development provides new insights into ear development, enables unique perspectives into the complex development of the ear, and allows for the first full quantification of volumetric and linear aspects of ear growth. Our data provide the framework for future analysis of mutant phenotypes that are currently under-appreciated using only two dimensional renderings. PMID:22271591

Scanning thin-sheet laser imaging microscopy elucidates details on mouse ear development.

PubMed

Kopecky, Benjamin; Johnson, Shane; Schmitz, Heather; Santi, Peter; Fritzsch, Bernd

2012-03-01

The mammalian inner ear is transformed from a flat placode into a three-dimensional (3D) structure with six sensory epithelia that allow for the perception of sound and both linear and angular acceleration. While hearing and balance problems are typically considered to be adult onset diseases, they may arise as a developmental perturbation to the developing ear. Future prevention of hearing or balance loss requires an understanding of how closely genetic mutations in model organisms reflect the human case, necessitating an objective multidimensional comparison of mouse ears with human ears that have comparable mutations in the same gene. Here, we present improved 3D analyses of normal murine ears during embryonic development using optical sections obtained through Thin-Sheet Laser Imaging Microscopy. We chronicle the transformation of an undifferentiated otic vesicle between mouse embryonic day 11.5 to a fully differentiated inner ear at postnatal day 15. Our analysis of ear development provides new insights into ear development, enables unique perspectives into the complex development of the ear, and allows for the first full quantification of volumetric and linear aspects of ear growth. Our data provide the framework for future analysis of mutant phenotypes that are currently under-appreciated using only two dimensional renderings. Copyright © 2012 Wiley Periodicals, Inc.

Evolution of vertebrate mechanosensory hair cells and inner ears: toward identifying stimuli that select mutation driven altered morphologies

PubMed Central

Fritzsch, Bernd; Straka, Hans

2014-01-01

Among the major distance senses of vertebrates, the ear is unique in its complex morphological changes during evolution. Conceivably, these changes enable the ear to adapt toward sensing various physically well-characterized stimuli. This review develops a scenario that integrates sensory cell with organ evolution. We propose that molecular and cellular evolution of the vertebrate hair cells occurred prior to the formation of the vertebrate ear. We previously proposed that the genes driving hair cell differentiation, were aggregated in the otic region through developmental re-patterning that generated a unique vertebrate embryonic structure, the otic placode. In agreement with the presence of graviceptive receptors in many vertebrate outgroups, it is likely that the vertebrate ear originally functioned as a simple gravity-sensing organ. Based on the rare occurrence of angular acceleration receptors in vertebrate outgroups, we further propose that the canal system evolved with a more sophisticated ear morphogenesis. This evolving morphogenesis obviously turned the initial otocyst into a complex set of canals and recesses, harboring multiple sensory epithelia each adapted to the acquisition of a specific aspect of a given physical stimulus. As support for this evolutionary progression, we provide several details of the molecular basis of ear development. PMID:24281353

Regulated reprogramming in the regeneration of sensory receptor cells

PubMed Central

Bermingham-McDonogh, Olivia; Reh, Thomas A.

2015-01-01

The sensory reception of vision, olfaction, hearing and balance are mediated by receptors that reside in specialized epithelial organs. Age-related degeneration of the photoreceptors in the retina and the hair cells in the cochlea, caused by macular degeneration and sensorineural hearing loss, respectively, affect a growing number of individuals. Although sensory receptor cells in the mammalian retina and inner ear show only limited or no regeneration, in many non-mammalian vertebrates, these sensory epithelia show remarkable regenerative potential. We summarize the current state of knowledge of regeneration in the specialized sense organs in both non-mammalian vertebrates and mammals, and discuss possible areas where new advances in regenerative medicine might provide approaches to successfully stimulate sensory receptor cell regeneration. The field of regenerative medicine is still in its infancy, but new approaches using stem cells and reprogramming suggest ways in which the potential for regeneration may be restored in individuals suffering from sensory loss. PMID:21835338

Calcium Gradients in the Fish inner Ear sensory Epithelium and otolithic Membrane: an Energy filtering Transmission electron Microscopy (EFTEM) Study

NASA Astrophysics Data System (ADS)

Ibsch, M.; Anken, R.; Rahmann, H.

Inner ear otolith formation in fish is supposed to be performed by the molecular release of proteinacious precursor material from the sensory epithelia, followed by an undirected and diffuse precipitation of calcium carbonate (which is mainly responsible for the functionally important weight of otoliths). Previous experiments have shown, however, that otolith formation in terms of provision both of the protein matrix and of calcium is regulated by a (likely neuronal) feedback mechanism. This regulating mechanism effects a symmetrical crystallisation of the corresponding otoliths in the inner ears of both sides of the head, which is necessary for a correct graviperception and for maintenance of postural control; thus, asymmetrical otoliths can induce kinetoses (e.g., space motion sickness) both in human and fish. On the background of an obviously directed incorporation of calcium into otoliths, the site of origin of the otoliths's inorganic components such as calcium still remains obscure. Therefore, ultrastructural and element analytical investigations were undertaken to screen the calcium distribution within the macular epithelial region using fish as model system. Electron spectroscopic imaging (ESI) and electron energy loss spectra (EELS) revealed discrete calcium-precipitations in the extracellular space of the otolithic membrane as well as within the lumina of the epithelial sensory cells. The calcium particles were accumulated at the macular tight junctions and seemed to be distributed in an ascending intracellular and a descending extracellular gradient towards the otolith. Further distinct calcium containing crystals covered the peripheral proteinacious layer of the otolith. The remaining endolymphatic space of the otocyst was lacking calcium precipitates. Overall, the present results indicate that the apical region of the macular epithelium is involved in the controlled release of calcium. This finding is in complete agreement with a study using calcium

The molecular basis of neurosensory cell formation in ear development: a blueprint for hair cell and sensory neuron regeneration?

PubMed Central

Fritzsch, Bernd; Beisel, Kirk W.; Hansen, Laura

2014-01-01

Summary The inner ear of mammals uses neurosensory cells derived from the embryonic ear for mechanoelectric transduction of vestibular and auditory stimuli (the hair cells) and conducts this information to the brain via sensory neurons. As with most other neurons of mammals, lost hair cells and sensory neurons are not spontaneously replaced and result instead in age-dependent progressive hearing loss. We review the molecular basis of neurosensory development in the mouse ear to provide a blueprint for possible enhancement of therapeutically useful transformation of stem cells into lost neurosensory cells. We identify several readily available adult sources of stem cells that express, like the ectoderm-derived ear, genes known to be essential for ear development. Use of these stem cells combined with molecular insights into neurosensory cell specification and proliferation regulation of the ear, might allow for neurosensory regeneration of mammalian ears in the near future. PMID:17120192

Generation of inner ear sensory cells from bone marrow-derived human mesenchymal stem cells.

PubMed

Durán Alonso, M Beatriz; Feijoo-Redondo, Ana; Conde de Felipe, Magnolia; Carnicero, Estela; García, Ana Sánchez; García-Sancho, Javier; Rivolta, Marcelo N; Giráldez, Fernando; Schimmang, Thomas

2012-11-01

Hearing loss is the most common sensory disorder in humans, its main cause being the loss of cochlear hair cells. We studied the potential of human mesenchymal stem cells (hMSCs) to differentiate towards hair cells and auditory neurons. hMSCs were first differentiated to neural progenitors and subsequently to hair cell- or auditory neuron-like cells using in vitro culture methods. Differentiation of hMSCs to an intermediate neural progenitor stage was critical for obtaining inner ear sensory lineages. hMSCs generated hair cell-like cells only when neural progenitors derived from nonadherent hMSC cultures grown in serum-free medium were exposed to EGF and retinoic acid. Auditory neuron-like cells were obtained when treated with retinoic acid, and in the presence of defined growth factor combinations containing Sonic Hedgehog. The results show the potential of hMSCs to give rise to inner ear sensory cells.

Sensory hair cell death and regeneration in fishes

PubMed Central

Monroe, Jerry D.; Rajadinakaran, Gopinath; Smith, Michael E.

2015-01-01

Sensory hair cells are specialized mechanotransductive receptors required for hearing and vestibular function. Loss of hair cells in humans and other mammals is permanent and causes reduced hearing and balance. In the early 1980’s, it was shown that hair cells continue to be added to the inner ear sensory epithelia in cartilaginous and bony fishes. Soon thereafter, hair cell regeneration was documented in the chick cochlea following acoustic trauma. Since then, research using chick and other avian models has led to great insights into hair cell death and regeneration. However, with the rise of the zebrafish as a model organism for studying disease and developmental processes, there has been an increased interest in studying sensory hair cell death and regeneration in its lateral line and inner ears. Advances derived from studies in zebrafish and other fish species include understanding the effect of ototoxins on hair cells and finding otoprotectants to mitigate ototoxin damage, the role of cellular proliferation vs. direct transdifferentiation during hair cell regeneration, and elucidating cellular pathways involved in the regeneration process. This review will summarize research on hair cell death and regeneration using fish models, indicate the potential strengths and weaknesses of these models, and discuss several emerging areas of future studies. PMID:25954154

The zinc finger transcription factor Gfi1, implicated in lymphomagenesis, is required for inner ear hair cell differentiation and survival

NASA Technical Reports Server (NTRS)

Wallis, Deeann; Hamblen, Melanie; Zhou, Yi; Venken, Koen J T.; Schumacher, Armin; Grimes, H. Leighton; Zoghbi, Huda Y.; Orkin, Stuart H.; Bellen, Hugo J.

2003-01-01

Gfi1 was first identified as causing interleukin 2-independent growth in T cells and lymphomagenesis in mice. Much work has shown that Gfi1 and Gfi1b, a second mouse homolog, play pivotal roles in blood cell lineage differentiation. However, neither Gfi1 nor Gfi1b has been implicated in nervous system development, even though their invertebrate homologues, senseless in Drosophila and pag-3 in C. elegans are expressed and required in the nervous system. We show that Gfi1 mRNA is expressed in many areas that give rise to neuronal cells during embryonic development in mouse, and that Gfi1 protein has a more restricted expression pattern. By E12.5 Gfi1 mRNA is expressed in both the CNS and PNS as well as in many sensory epithelia including the developing inner ear epithelia. At later developmental stages, Gfi1 expression in the ear is refined to the hair cells and neurons throughout the inner ear. Gfi1 protein is expressed in a more restricted pattern in specialized sensory cells of the PNS, including the eye, presumptive Merkel cells, the lung and hair cells of the inner ear. Gfi1 mutant mice display behavioral defects that are consistent with inner ear anomalies, as they are ataxic, circle, display head tilting behavior and do not respond to noise. They have a unique inner ear phenotype in that the vestibular and cochlear hair cells are differentially affected. Although Gfi1-deficient mice initially specify inner ear hair cells, these hair cells are disorganized in both the vestibule and cochlea. The outer hair cells of the cochlea are improperly innervated and express neuronal markers that are not normally expressed in these cells. Furthermore, Gfi1 mutant mice lose all cochlear hair cells just prior to and soon after birth through apoptosis. Finally, by five months of age there is also a dramatic reduction in the number of cochlear neurons. Hence, Gfi1 is expressed in the developing nervous system, is required for inner ear hair cell differentiation, and its loss

MEKK4 Signaling Regulates Sensory Cell Development and Function in the Mouse Inner Ear

PubMed Central

Haque, Khujista; Pandey, Atul K.; Zheng, Hong-Wei; Riazuddin, Saima; Sha, Su-Hua

2016-01-01

Mechanosensory hair cells (HCs) residing in the inner ear are critical for hearing and balance. Precise coordination of proliferation, sensory specification, and differentiation during development is essential to ensure the correct patterning of HCs in the cochlear and vestibular epithelium. Recent studies have revealed that FGF20 signaling is vital for proper HC differentiation. However, the mechanisms by which FGF20 signaling promotes HC differentiation remain unknown. Here, we show that mitogen-activated protein 3 kinase 4 (MEKK4) expression is highly regulated during inner ear development and is critical to normal cytoarchitecture and function. Mice homozygous for a kinase-inactive MEKK4 mutation exhibit significant hearing loss. Lack of MEKK4 activity in vivo also leads to a significant reduction in the number of cochlear and vestibular HCs, suggesting that MEKK4 activity is essential for overall development of HCs within the inner ear. Furthermore, we show that loss of FGF20 signaling in vivo inhibits MEKK4 activity, whereas gain of Fgf20 function stimulates MEKK4 expression, suggesting that Fgf20 modulates MEKK4 activity to regulate cellular differentiation. Finally, we demonstrate, for the first time, that MEKK4 acts as a critical node to integrate FGF20-FGFR1 signaling responses to specifically influence HC development and that FGFR1 signaling through activation of MEKK4 is necessary for outer hair cell differentiation. Collectively, this study provides compelling evidence of an essential role for MEKK4 in inner ear morphogenesis and identifies the requirement of MEKK4 expression in regulating the specific response of FGFR1 during HC development and FGF20/FGFR1 signaling activated MEKK4 for normal sensory cell differentiation. SIGNIFICANCE STATEMENT Sensory hair cells (HCs) are the mechanoreceptors within the inner ear responsible for our sense of hearing. HCs are formed before birth, and mammals lack the ability to restore the sensory deficits associated

Continuous hair cell turnover in the inner ear vestibular organs of a mammal, the Daubenton's bat (Myotis daubentonii).

PubMed

Kirkegaard, M; Jørgensen, J M

2000-02-01

In both humans and mice the number of hair cells in the inner ear sensory epithelia declines with age, indicating cell death (Park et al. 1987; Rosenhall 1973). However, recent reports demonstrate the ability of the vestibular sensory epithelia to regenerate after injury (Forge et al. 1993, 1998; Kuntz and Oesterle 1998; Li and Forge 1997; Rubel et al. 1995; Tanyeri et al. 1995). Still, a continuous hair cell turnover in the vestibular epithelia has not previously been demonstrated in mature mammals. Bats are the only flying mammals, and they are known to live to a higher age than animals of equal size. The maximum age of many species is 20 years, with average lifespans of 4-6 years (Schober and Grimmberger 1989). Further, the young are fully developed and able to fly at the age of 2 months, and thus the vestibular organs are thought to be differentiated at that age. Consequently, long-lived mammals such as bats might compensate for the loss of hair cells by producing new hair cells in their postembryonic life. Here we show that the utricular macula of adult Daubenton's bats (more than 6 months old) contains innervated immature hair cells as well as apoptotic hair cells, which strongly indicates a continuous turnover of hair cells, as previously demonstrated in birds.

Continuous Hair Cell Turnover in the Inner Ear Vestibular Organs of a Mammal, the Daubenton's Bat (Myotis daubentonii)

NASA Astrophysics Data System (ADS)

Kirkegaard, M.; Jørgensen, J. M.

In both humans and mice the number of hair cells in the inner ear sensory epithelia declines with age, indicating cell death (Park et al. 1987; Rosenhall 1973). However, recent reports demonstrate the ability of the vestibular sensory epithelia to regenerate after injury (Forge et al. 1993, 1998; Kuntz and Oesterle 1998; Li and Forge 1997; Rubel et al. 1995; Tanyeri et al. 1995). Still, a continuous hair cell turnover in the vestibular epithelia has not previously been demonstrated in mature mammals. Bats are the only flying mammals, and they are known to live to a higher age than animals of equal size. The maximum age of many species is 20years, with average lifespans of 4-6years (Schober and Grimmberger 1989). Further, the young are fully developed and able to fly at the age of 2months, and thus the vestibular organs are thought to be differentiated at that age. Consequently, long-lived mammals such as bats might compensate for the loss of hair cells by producing new hair cells in their postembryonic life. Here we show that the utricular macula of adult Daubenton's bats (more than 6months old) contains innervated immature hair cells as well as apoptotic hair cells, which strongly indicates a continuous turnover of hair cells, as previously demonstrated in birds.

A short history of nearly every sense - The evolutionary history of vertebrate sensory cell types.

PubMed

Schlosser, Gerhard

2018-05-08

Evolving from filter feeding chordate ancestors, vertebrates adopted a more active life style. These ecological and behavioral changes went along with an elaboration of the vertebrate head including novel complex paired sense organs such as the eyes, inner ears and olfactory epithelia. However, the photoreceptors, mechanoreceptors and chemoreceptors used in these sense organs have a long evolutionary history and homologous cell types can be recognized in many other bilaterians or even cnidarians. After briefly introducing some of the major sensory cell types found in vertebrates, this review summarizes the phylogenetic distribution of sensory cell types in metazoans and presents a scenario for the evolutionary history of various sensory cell types involving several cell type diversification and fusion events. It is proposed that the evolution of novel cranial sense organs in vertebrates involved the redeployment of evolutionarily ancient sensory cell types for building larger and more complex sense organs.

Cisplatin ototoxicity blocks sensory regeneration in the avian inner ear.

PubMed

Slattery, Eric L; Warchol, Mark E

2010-03-03

Cisplatin is a chemotherapeutic agent that is widely used in the treatment of solid tumors. Ototoxicity is a common side effect of cisplatin therapy and often leads to permanent hearing loss. The sensory organs of the avian ear are able to regenerate hair cells after aminoglycoside ototoxicity. This regenerative response is mediated by supporting cells, which serve as precursors to replacement hair cells. Given the antimitotic properties of cisplatin, we examined whether the avian ear was also capable of regeneration after cisplatin ototoxicity. Using cell and organ cultures of the chick cochlea and utricle, we found that cisplatin treatment caused apoptosis of both auditory and vestibular hair cells. Hair cell death in the cochlea occurred in a unique pattern, progressing from the low-frequency (distal) region toward the high-frequency (proximal) region. We also found that cisplatin caused a dose-dependent reduction in the proliferation of cultured supporting cells as well as increased apoptosis in those cells. As a result, we observed no recovery of hair cells after ototoxic injury caused by cisplatin. Finally, we explored the potential for nonmitotic hair cell recovery via activation of Notch pathway signaling. Treatment with the gamma-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester failed to promote the direct transdifferentiation of supporting cells into hair cells in cisplatin-treated utricles. Taken together, our data show that cisplatin treatment causes maintained changes to inner ear supporting cells and severely impairs the ability of the avian ear to regenerate either via proliferation or by direct transdifferentiation.

Insights into inner ear-specific gene regulation: epigenetics and non-coding RNAs in inner ear development and regeneration

PubMed Central

Avraham, Karen B.

2016-01-01

The vertebrate inner ear houses highly specialized sensory organs, tuned to detect and encode sound, head motion and gravity. Gene expression programs under the control of transcription factors orchestrate the formation and specialization of the non-sensory inner ear labyrinth and its sensory constituents. More recently, epigenetic factors and non-coding RNAs emerged as an additional layer of gene regulation, both in inner ear development and disease. In this review, we provide an overview on how epigenetic modifications and non-coding RNAs, in particular microRNAs (miRNAs), influence gene expression and summarize recent discoveries that highlight their critical role in the proper formation of the inner ear labyrinth and its sensory organs. In contrast to non-mammalian vertebrates, adult mammals lack the ability to regenerate inner ear mechano-sensory hair cells. Finally, we discuss recent insights into how epigenetic factors and miRNAs may facilitate, or in the case of mammals, restrict sensory hair cell regeneration. PMID:27836639

Ephrin-B2 governs morphogenesis of endolymphatic sac and duct epithelia in the mouse inner ear.

PubMed

Raft, Steven; Andrade, Leonardo R; Shao, Dongmei; Akiyama, Haruhiko; Henkemeyer, Mark; Wu, Doris K

2014-06-01

Control over ionic composition and volume of the inner ear luminal fluid endolymph is essential for normal hearing and balance. Mice deficient in either the EphB2 receptor tyrosine kinase or the cognate transmembrane ligand ephrin-B2 (Efnb2) exhibit background strain-specific vestibular-behavioral dysfunction and signs of abnormal endolymph homeostasis. Using various loss-of-function mouse models, we found that Efnb2 is required for growth and morphogenesis of the embryonic endolymphatic epithelium, a precursor of the endolymphatic sac (ES) and duct (ED), which mediate endolymph homeostasis. Conditional inactivation of Efnb2 in early-stage embryonic ear tissues disrupted cell proliferation, cell survival, and epithelial folding at the origin of the endolymphatic epithelium. This correlated with apparent absence of an ED, mis-localization of ES ion transport cells relative to inner ear sensory organs, dysplasia of the endolymph fluid space, and abnormally formed otoconia (extracellular calcite-protein composites) at later stages of embryonic development. A comparison of Efnb2 and Notch signaling-deficient mutant phenotypes indicated that these two signaling systems have distinct and non-overlapping roles in ES/ED development. Homozygous deletion of the Efnb2 C-terminus caused abnormalities similar to those found in the conditional Efnb2 null homozygote. Analyses of fetal Efnb2 C-terminus deletion heterozygotes found mis-localized ES ion transport cells only in the genetic background exhibiting vestibular dysfunction. We propose that developmental dysplasias described here are a gene dose-sensitive cause of the vestibular dysfunction observed in EphB-Efnb2 signaling-deficient mice. Published by Elsevier Inc.

Ephrin-B2 governs morphogenesis of endolymphatic sac and duct epithelia in the mouse inner ear

PubMed Central

Raft, Steven; Andrade, Leonardo R.; Shao, Dongmei; Akiyama, Haruhiko; Henkemeyer, Mark; Wu, Doris K.

2014-01-01

Control over ionic composition and volume of the inner ear luminal fluid endolymph is essential for normal hearing and balance. Mice deficient in either the EphB2 receptor tyrosine kinase or the cognate transmembrane ligand ephrin-B2 (Efnb2) exhibit background strain-specific vestibular behavioral dysfunction and signs of abnormal endolymph homeostasis. Using various loss-of-function mouse models, we found that Efnb2 is required for growth and morphogenesis of the embryonic endolymphatic epithelium, a precursor of the endolymphatic sac (ES) and duct (ED), which mediate endolymph homeostasis. Conditional inactivation of Efnb2 in early-stage embryonic ear tissues disrupted cell proliferation, cell survival, and epithelial folding at the origin of the endolymphatic epithelium. This correlated with apparent absence of an ED, mis-localization of ES ion transport cells relative to inner ear sensory organs, dysplasia of the endolymph fluid space, and abnormally formed otoconia (extracellular calcite protein composites) at later stages of embryonic development. A comparison of Efnb2 and Notch signaling deficient mutant phenotypes indicated that these two signaling systems have distinct and non overlapping roles in ES/ED development. Homozygous deletion of the Efnb2 C terminus caused abnormalities similar to those found in the conditional Efnb2 null homozygote. Analyses of fetal Efnb2 C-terminus deletion heterozygotes found mis-localized ES ion transport cells only in the genetic background exhibiting vestibular dysfunction. We propose that developmental dysplasias described here are a gene dose sensitive cause of the vestibular dysfunction observed in EphB-Efnb2 signaling-deficient mice. PMID:24583262

Hair cell regeneration in sensory epithelia from the inner ear of a urodele amphibian.

PubMed

Taylor, Ruth R; Forge, Andrew

2005-03-28

The capacity of urodele amphibians to regenerate a variety of body parts is providing insight into mechanisms of tissue regeneration in vertebrates. In this study the ability of the newt, Notophthalmus viridescens, to regenerate inner ear hair cells in vitro was examined. Intact otic capsules were maintained in organotypic culture. Incubation in 2 mM gentamicin for 48 hours resulted in ablation of all hair cells from the saccular maculae. Thus, any hair cell recovery was not due to repair of damaged hair cells. Immature hair cells were subsequently observed at approximately 12 days posttreatment. Their number increased over the following 7-14 days to reach approximately 30% of the normal number. Following incubation of damaged tissue with bromodeoxyuridine (BrdU), labeled nuclei were confined strictly within regions of hair cell loss, indicating that supporting cells entered S-phase. Double labeling of tissue with two different hair cell markers and three different antibodies to BrdU in various combinations, however, all showed that the nuclei of cells that labeled with hair cell markers did not label for BrdU. This suggested that the new hair cells were not derived from those cells that had undergone mitosis. When mitosis was blocked with aphidicolin, new hair cells were still generated. The results suggest that direct phenotypic conversion of supporting cells into hair cells without an intervening mitotic event is a major mechanism of hair cell regeneration in the newt. A similar mechanism has been proposed for the hair cell recovery phenomenon observed in the vestibular organs of mammals. Copyright 2005 Wiley-Liss, Inc.

Epigenetic influences on sensory regeneration: histone deacetylases regulate supporting cell proliferation in the avian utricle.

PubMed

Slattery, Eric L; Speck, Judith D; Warchol, Mark E

2009-09-01

The sensory hair cells of the cochlea and vestibular organs are essential for normal hearing and balance function. The mammalian ear possesses a very limited ability to regenerate hair cells and their loss can lead to permanent sensory impairment. In contrast, hair cells in the avian ear are quickly regenerated after acoustic trauma or ototoxic injury. The very different regenerative abilities of the avian vs. mammalian ear can be attributed to differences in injury-evoked expression of genes that either promote or inhibit the production of new hair cells. Gene expression is regulated both by the binding of cis-regulatory molecules to promoter regions as well as through structural modifications of chromatin (e.g., methylation and acetylation). This study examined effects of histone deacetylases (HDACs), whose main function is to modify histone acetylation, on the regulation of regenerative proliferation in the chick utricle. Cultures of regenerating utricles and dissociated cells from the utricular sensory epithelia were treated with the HDAC inhibitors valproic acid, trichostatin A, sodium butyrate, and MS-275. All of these molecules prevent the enzymatic removal of acetyl groups from histones, thus maintaining nuclear chromatin in a "relaxed" (open) configuration. Treatment with all inhibitors resulted in comparable decreases in supporting cell proliferation. We also observed that treatment with the HDAC1-, 2-, and 3-specific inhibitor MS-275 was sufficient to reduce proliferation and that two class I HDACs--HDAC1 and HDAC2--were expressed in the sensory epithelium of the utricle. These results suggest that inhibition of specific type I HDACs is sufficient to prevent cell cycle entry in supporting cells. Notably, treatment with HDAC inhibitors did not affect the differentiation of replacement hair cells. We conclude that histone deacetylation is a positive regulator of regenerative proliferation but is not critical for avian hair cell differentiation.

Mature middle and inner ears express Chd7 and exhibit distinctive pathologies in a mouse model of CHARGE syndrome

PubMed Central

Hurd, Elizabeth A.; Adams, Meredith E.; Layman, Wanda S.; Swiderski, Donald L.; Beyer, Lisa A.; Halsey, Karin E.; Benson, Jennifer M.; Gong, Tzy-Wen; Dolan, David F.; Raphael, Yehoash; Martin, Donna M.

2011-01-01

Heterozygous mutations in the gene encoding chromodomain-DNA-binding-protein 7 (CHD7) cause CHARGE syndrome, a multiple anomaly condition which includes vestibular dysfunction and hearing loss. Mice with heterozygous Chd7 mutations exhibit semicircular canal dysgenesis and abnormal inner ear neurogenesis, and are an excellent model of CHARGE syndrome. Here we characterized Chd7 expression in mature middle and inner ears, analyzed morphological features of mutant ears and tested whether Chd7 mutant mice have altered responses to noise exposure and correlated those responses to inner and middle ear structure. We found that Chd7 is highly expressed in mature inner and outer hair cells, spiral ganglion neurons, vestibular sensory epithelia and middle ear ossicles. There were no obvious defects in individual hair cell morphology by Prestin immunostaining or scanning electron microscopy, and cochlear innervation appeared normal in Chd7Gt/+ mice. Hearing thresholds by auditory brainstem response (ABR) testing were elevated at 4 and 16 kHz in Chd7Gt/+ mice, and there were reduced distortion product otoacoustic emissions (DPOAE). Exposure of Chd7Gt/+ mice to broadband noise resulted in variable degrees of hair cell loss which inversely correlated with severity of stapedial defects. The degrees of hair cell loss and threshold shifts after noise exposure were more severe in wild type mice than in mutants. Together, these data indicate that Chd7Gt/+ mice have combined conductive and sensorineural hearing loss, correlating with changes in both middle and inner ears. PMID:21875659

BODIPY-Conjugated Xyloside Primes Fluorescent Glycosaminoglycans in the Inner Ear of Opsanus tau.

PubMed

Holman, Holly A; Tran, Vy M; Kalita, Mausam; Nguyen, Lynn N; Arungundram, Sailaja; Kuberan, Balagurunathan; Rabbitt, Richard D

2016-12-01

We report on a new xyloside conjugated to BODIPY, BX and its utility to prime fluorescent glycosaminoglycans (BX-GAGs) within the inner ear in vivo. When BX is administered directly into the endolymphatic space of the oyster toadfish (Opsanus tau) inner ear, fluorescent BX-GAGs are primed and become visible in the sensory epithelia of the semicircular canals, utricle, and saccule. Confocal and 2-photon microscopy of vestibular organs fixed 4 h following BX treatment, reveal BX-GAGs constituting glycocalyces that envelop hair cell kinocilium, nerve fibers, and capillaries. In the presence of GAG-specific enzymes, the BX-GAG signals are diminished, suggesting that chondroitin sulfates are the primary GAGs primed by BX. Results are consistent with similar click-xylosides in CHO cell lines, where the xyloside enters the Golgi and preferentially initiates chondroitin sulfate B production. Introduction of BX produces a temporary block of hair cell mechanoelectrical transduction (MET) currents in the crista, reduction in background discharge rate of afferent neurons, and a reduction in sensitivity to physiological stimulation. A six-degree-of-freedom pharmacokinetic mathematical model has been applied to interpret the time course and spatial distribution of BX and BX-GAGs. Results demonstrate a new optical approach to study GAG biology in the inner ear, for tracking synthesis and localization in real time.

Inner ear tissue preservation by rapid freezing: Improving fixation by high-pressure freezing and hybrid methods

PubMed Central

Bullen, A.; Taylor, R.R.; Kachar, B.; Moores, C.; Fleck, R.A.; Forge, A.

2014-01-01

In the preservation of tissues in as ‘close to life’ state as possible, rapid freeze fixation has many benefits over conventional chemical fixation. One technique by which rapid freeze-fixation can be achieved, high pressure freezing (HPF), has been shown to enable ice crystal artefact-free freezing and tissue preservation to greater depths (more than 40 μm) than other quick-freezing methods. Despite increasingly becoming routine in electron microscopy, the use of HPF for the fixation of inner ear tissue has been limited. Assessment of the quality of preservation showed routine HPF techniques were suitable for preparation of inner ear tissues in a variety of species. Good preservation throughout the depth of sensory epithelia was achievable. Comparison to chemically fixed tissue indicated that fresh frozen preparations exhibited overall superior structural preservation of cells. However, HPF fixation caused characteristic artefacts in stereocilia that suggested poor quality freezing of the actin bundles. The hybrid technique of pre-fixation and high pressure freezing was shown to produce cellular preservation throughout the tissue, similar to that seen in HPF alone. Pre-fixation HPF produced consistent high quality preservation of stereociliary actin bundles. Optimising the preparation of samples with minimal artefact formation allows analysis of the links between ultrastructure and function in inner ear tissues. PMID:25016142

Differential Transmission of HIV Traversing Fetal Oral/Intestinal Epithelia and Adult Oral Epithelia

PubMed Central

Herrera, Rossana; Veluppillai, Piri; Greenspan, Deborah; Soros, Vanessa; Greene, Warner C.; Levy, Jay A.; Palefsky, Joel M.

2012-01-01

While human immunodeficiency virus (HIV) transmission through the adult oral route is rare, mother-to-child transmission (MTCT) through the neonatal/infant oral and/or gastrointestinal route is common. To study the mechanisms of cell-free and cell-associated HIV transmission across adult oral and neonatal/infant oral/intestinal epithelia, we established ex vivo organ tissue model systems of adult and fetal origin. Given the similarity of neonatal and fetal oral epithelia with respect to epithelial stratification and density of HIV-susceptible immune cells, we used fetal oral the epithelium as a model for neonatal/infant oral epithelium. We found that cell-free HIV traversed fetal oral and intestinal epithelia and infected HIV-susceptible CD4+ T lymphocytes, Langerhans/dendritic cells, and macrophages. To study the penetration of cell-associated virus into fetal oral and intestinal epithelia, HIV-infected macrophages and lymphocytes were added to the surfaces of fetal oral and intestinal epithelia. HIV-infected macrophages, but not lymphocytes, transmigrated across fetal oral epithelia. HIV-infected macrophages and, to a lesser extent, lymphocytes transmigrated across fetal intestinal epithelia. In contrast to the fetal oral/intestinal epithelia, cell-free HIV transmigration through adult oral epithelia was inefficient and virions did not infect intraepithelial and subepithelial HIV-susceptible cells. In addition, HIV-infected macrophages and lymphocytes did not transmigrate through intact adult oral epithelia. Transmigration of cell-free and cell-associated HIV across the fetal oral/intestinal mucosal epithelium may serve as an initial mechanism for HIV MTCT. PMID:22205732

A simple method for purification of vestibular hair cells and non-sensory cells, and application for proteomic analysis.

PubMed

Herget, Meike; Scheibinger, Mirko; Guo, Zhaohua; Jan, Taha A; Adams, Christopher M; Cheng, Alan G; Heller, Stefan

2013-01-01

Mechanosensitive hair cells and supporting cells comprise the sensory epithelia of the inner ear. The paucity of both cell types has hampered molecular and cell biological studies, which often require large quantities of purified cells. Here, we report a strategy allowing the enrichment of relatively pure populations of vestibular hair cells and non-sensory cells including supporting cells. We utilized specific uptake of fluorescent styryl dyes for labeling of hair cells. Enzymatic isolation and flow cytometry was used to generate pure populations of sensory hair cells and non-sensory cells. We applied mass spectrometry to perform a qualitative high-resolution analysis of the proteomic makeup of both the hair cell and non-sensory cell populations. Our conservative analysis identified more than 600 proteins with a false discovery rate of <3% at the protein level and <1% at the peptide level. Analysis of proteins exclusively detected in either population revealed 64 proteins that were specific to hair cells and 103 proteins that were only detectable in non-sensory cells. Statistical analyses extended these groups by 53 proteins that are strongly upregulated in hair cells versus non-sensory cells and vice versa by 68 proteins. Our results demonstrate that enzymatic dissociation of styryl dye-labeled sensory hair cells and non-sensory cells is a valid method to generate pure enough cell populations for flow cytometry and subsequent molecular analyses.

Ontogenetic development of the inner ear saccule and utricle in the Lusitanian toadfish: Potential implications for auditory sensitivity.

PubMed

Chaves, Patrícia P; Valdoria, Ciara M C; Amorim, M Clara P; Vasconcelos, Raquel O

2017-09-01

Studies addressing structure-function relationships of the fish auditory system during development are sparse compared to other taxa. The Batrachoididae has become an important group to investigate mechanisms of auditory plasticity and evolution of auditory-vocal systems. A recent study reported ontogenetic improvements in the inner ear saccule sensitivity of the Lusitanian toadfish, Halobatrachus didactylus, but whether this results from changes in the sensory morphology remains unknown. We investigated how the macula and organization of auditory receptors in the saccule and utricle change during growth in this species. Inner ear sensory epithelia were removed from the end organs of previously PFA-fixed specimens, from non-vocal posthatch fry (<1.4 cm, standard length) to adults (>23 cm). Epithelia were phalloidin-stained and analysed for area, shape, number and orientation patterns of hair cells (HC), and number and size of saccular supporting cells (SC). Saccular macula area expanded 41x in total, and significantly more (relative to body length) among vocal juveniles (2.3-2.9 cm). Saccular HC number increased 25x but HC density decreased, suggesting that HC addition is slower relative to epithelial growth. While SC density decreased, SC apical area increased, contributing to the epithelial expansion. The utricule revealed increased HC density (striolar region) and less epithelial expansion (5x) with growth, contrasting with the saccule that may have a different developmental pattern due to its larger size and main auditory functions. Both macula shape and HC orientation patterns were already established in the posthatch fry and retained throughout growth in both end organs. We suggest that previously reported ontogenetic improvements in saccular sensitivity might be associated with changes in HC number (not density), size and/or molecular mechanisms controlling HC sensitivity. This is one of the first studies investigating the ontogenetic development of the

Mature middle and inner ears express Chd7 and exhibit distinctive pathologies in a mouse model of CHARGE syndrome.

PubMed

Hurd, Elizabeth A; Adams, Meredith E; Layman, Wanda S; Swiderski, Donald L; Beyer, Lisa A; Halsey, Karin E; Benson, Jennifer M; Gong, Tzy-Wen; Dolan, David F; Raphael, Yehoash; Martin, Donna M

2011-12-01

Heterozygous mutations in the gene encoding chromodomain-DNA-binding-protein 7 (CHD7) cause CHARGE syndrome, a multiple anomaly condition which includes vestibular dysfunction and hearing loss. Mice with heterozygous Chd7 mutations exhibit semicircular canal dysgenesis and abnormal inner ear neurogenesis, and are an excellent model of CHARGE syndrome. Here we characterized Chd7 expression in mature middle and inner ears, analyzed morphological features of mutant ears and tested whether Chd7 mutant mice have altered responses to noise exposure and correlated those responses to inner and middle ear structure. We found that Chd7 is highly expressed in mature inner and outer hair cells, spiral ganglion neurons, vestibular sensory epithelia and middle ear ossicles. There were no obvious defects in individual hair cell morphology by prestin immunostaining or scanning electron microscopy, and cochlear innervation appeared normal in Chd7(Gt)(/+) mice. Hearing thresholds by auditory brainstem response (ABR) testing were elevated at 4 and 16 kHz in Chd7(Gt)(/+) mice, and there were reduced distortion product otoacoustic emissions (DPOAE). Exposure of Chd7(Gt)(/+) mice to broadband noise resulted in variable degrees of hair cell loss which inversely correlated with severity of stapedial defects. The degrees of hair cell loss and threshold shifts after noise exposure were more severe in wild type mice than in mutants. Together, these data indicate that Chd7(Gt)(/+) mice have combined conductive and sensorineural hearing loss, correlating with changes in both middle and inner ears. Copyright © 2011 Elsevier B.V. All rights reserved.

In Vivo Analysis of Lrig Genes Reveals Redundant and Independent Functions in the Inner Ear

PubMed Central

del Rio, Tony; Nishitani, Allison M.; Yu, Wei-Ming; Goodrich, Lisa V.

2013-01-01

Lrig proteins are conserved transmembrane proteins that modulate a variety of signaling pathways from worm to humans. In mammals, there are three family members – Lrig1, Lrig2, and Lrig3 – that are defined by closely related extracellular domains with a similar arrangement of leucine rich repeats and immunoglobulin domains. However, the intracellular domains show little homology. Lrig1 inhibits EGF signaling through internalization and degradation of ErbB receptors. Although Lrig3 can also bind ErbB receptors in vitro, it is unclear whether Lrig2 and Lrig3 exhibit similar functions to Lrig1. To gain insights into Lrig gene functions in vivo, we compared the expression and function of the Lrigs in the inner ear, which offers a sensitive system for detecting effects on morphogenesis and function. We find that all three family members are expressed in the inner ear throughout development, with Lrig1 and Lrig3 restricted to subsets of cells and Lrig2 expressed more broadly. Lrig1 and Lrig3 overlap prominently in the developing vestibular apparatus and simultaneous removal of both genes disrupts inner ear morphogenesis. This suggests that these two family members act redundantly in the otic epithelium. In contrast, although Lrig1 and Lrig2 are frequently co-expressed, Lrig1−/−;Lrig2−/− double mutant ears show no enhanced structural abnormalities. At later stages, Lrig1 expression is sustained in non-sensory tissues, whereas Lrig2 levels are enhanced in neurons and sensory epithelia. Consistent with these distinct expression patterns, Lrig1 and Lrig2 mutant mice exhibit different forms of impaired auditory responsiveness. Notably, Lrig1−/−;Lrig2−/− double mutant mice display vestibular deficits and suffer from a more severe auditory defect that is accompanied by a cochlear innervation phenotype not present in single mutants. Thus, Lrig genes appear to act both redundantly and independently, with Lrig2 emerging as the most functionally distinct family

Inner ear tissue preservation by rapid freezing: improving fixation by high-pressure freezing and hybrid methods.

PubMed

Bullen, A; Taylor, R R; Kachar, B; Moores, C; Fleck, R A; Forge, A

2014-09-01

In the preservation of tissues in as 'close to life' state as possible, rapid freeze fixation has many benefits over conventional chemical fixation. One technique by which rapid freeze-fixation can be achieved, high pressure freezing (HPF), has been shown to enable ice crystal artefact-free freezing and tissue preservation to greater depths (more than 40 μm) than other quick-freezing methods. Despite increasingly becoming routine in electron microscopy, the use of HPF for the fixation of inner ear tissue has been limited. Assessment of the quality of preservation showed routine HPF techniques were suitable for preparation of inner ear tissues in a variety of species. Good preservation throughout the depth of sensory epithelia was achievable. Comparison to chemically fixed tissue indicated that fresh frozen preparations exhibited overall superior structural preservation of cells. However, HPF fixation caused characteristic artefacts in stereocilia that suggested poor quality freezing of the actin bundles. The hybrid technique of pre-fixation and high pressure freezing was shown to produce cellular preservation throughout the tissue, similar to that seen in HPF alone. Pre-fixation HPF produced consistent high quality preservation of stereociliary actin bundles. Optimising the preparation of samples with minimal artefact formation allows analysis of the links between ultrastructure and function in inner ear tissues. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Hair cell regeneration

PubMed Central

Edge, Albert SB; Chen, Zheng-Yi

2017-01-01

The mammalian inner ear largely lacks the capacity to regenerate hair cells, the sensory cells required for hearing and balance. Recent studies in both lower vertebrates and mammals have uncovered genes and pathways important in hair cell development and have suggested ways that the sensory epithelia could be manipulated to achieve hair cell regeneration. These approaches include the use of inner ear stem cells, transdifferentiation of nonsensory cells, and induction of a proliferative response in the cells that can become hair cells. PMID:18929656

Investigating Science Student Teachers' Ideas about Function and Anatomical Form of Two Human Sensory Organs, the Eye and the Ear

ERIC Educational Resources Information Center

Kunt, Halil

2016-01-01

The purpose of this research was to determine science student teachers' level of knowledge about the anatomical structure of two sensory organs, the eye and the ear, in addition to vision and hearing processes. Conducted with 86 science student teachers, research utilized drawing methods and open-ended questions as data collection instruments. The…

Wild-type cells rescue genotypically Math1-null hair cells in the inner ears of chimeric mice.

PubMed

Du, Xiaoping; Jensen, Patricia; Goldowitz, Daniel; Hamre, Kristin M

2007-05-15

The transcription factor Math1 has been shown to be critical in the formation of hair cells (HCs) in the inner ear. However, the influence of environmental factors in HC specification suggests that cell extrinsic factors are also crucial to their development. To test whether extrinsic factors impact development of Math1-null (Math1(beta-Gal/beta-Gal)) HCs, we examined neonatal (postnatal ages P0-P4.5) Math1-null chimeric mice in which genotypically mutant and wild-type cells intermingle to form the inner ear. We provide the first direct evidence that Math1-null HCs are able to be generated and survive in the conducive chimeric environment. beta-Galactosidase expression was used to identify genetically mutant cells while cells were phenotypically defined as HCs by morphological characteristics notably the expression of HC-specific markers. Genotypically mutant HCs were found in all sensory epithelia of the inner ear at all ages examined. Comparable results were obtained irrespective of the wild-type component of the chimeric mice. Thus, genotypically mutant cells retain the competence to differentiate into HCs. The implication is that the lack of the Math1 gene in HC precursors can be overcome by environmental influences, such as cell-cell interactions with wild-type cells, to ultimately result in the formation of HCs.

Zebrafish Foxi1 provides a neuronal ground state during inner ear induction preceding the Dlx3b/4b-regulated sensory lineage.

PubMed

Hans, Stefan; Irmscher, Anne; Brand, Michael

2013-05-01

Vertebrate inner ear development is a complex process that involves the induction of a common territory for otic and epibranchial precursors and their subsequent segregation into otic and epibranchial cell fates. In zebrafish, the otic-epibranchial progenitor domain (OEPD) is induced by Fgf signaling in a Foxi1- and Dlx3b/4b-dependent manner, but the functional differences of Foxi1 and Dlx3b/4b in subsequent cell fate specifications within the developing inner ear are poorly understood. Based on pioneer tracking (PioTrack), a novel Cre-dependent genetic lineage tracing method, and genetic data, we show that the competence to embark on a neuronal or sensory fate is provided sequentially and very early during otic placode induction. Loss of Foxi1 prevents neuronal precursor formation without affecting hair cell specification, whereas loss of Dlx3b/4b inhibits hair cell but not neuronal precursor formation. Consistently, in Dlx3b/4b- and Sox9a-deficient b380 mutants almost all otic epithelial fates are absent, including sensory hair cells, and the remaining otic cells adopt a neuronal fate. Furthermore, the progenitors of the anterior lateral line ganglia also arise from the OEPD in a Foxi1-dependent manner but are unaffected in the absence of Dlx3b/4b or in b380 mutants. Thus, in addition to otic fate Foxi1 provides neuronal competence during OEPD induction prior to and independently of the Dlx3b/4b-mediated sensory fate of the developing inner ear.

NOTCH SIGNALING ALTERS SENSORY OR NEURONAL CELL FATE SPECIFICATION OF INNER EAR STEM CELLS

PubMed Central

Jeon, Sang-Jun; Fujioka, Masato; Kim, Shi-Chan; Edge, Albert S.B.

2011-01-01

Multipotent progenitor cells in the otic placode give rise to the specialized cell types of the inner ear, including neurons, supporting cells and hair cells. The mechanisms governing acquisition of specific fates by the cells that form the cochleovestibular organs remain poorly characterized. Here we show that whereas blocking Notch signaling with a γ-secretase inhibitor increased the conversion of inner ear stem cells to hair cells by a mechanism that involved the upregulation of bHLH transcription factor, Math1 (mouse Atoh1), differentiation to a neuronal lineage was increased by expression of the Notch intracellular domain. The shift to a neuronal lineage could be attributed in part to the continued cell proliferation in cells that did not undergo sensory cell differentiation due to the high Notch signaling, but also involved upregulation of Ngn1. The Notch intracellular domain influenced Ngn1 indirectly by upregulation of Sox2, a transcription factor expressed in many neural progenitor cells, and directly by an interaction with an RBP-J binding site in the Ngn1 promoter/enhancer. The induction of Ngn1 was blocked partially by mutation of the RBP-J site and nearly completely when the mutation was combined with inhibition of Sox2 expression. Thus Notch signaling had a significant role in the fate specification of neurons and hair cells from inner ear stem cells, and decisions about cell fate were mediated in part by a differential effect of combinatorial signaling by Notch and Sox2 on the expression of bHLH transcription factors. PMID:21653840

Evaluation of the chemical model of vestibular lesions induced by arsanilate in rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vignaux, G.; Univ Caen, Caen, F-14000; Chabbert, C.

Several animal models of vestibular deficits that mimic the human pathology phenotype have previously been developed to correlate the degree of vestibular injury to cognate vestibular deficits in a time-dependent manner. Sodium arsanilate is one of the most commonly used substances for chemical vestibular lesioning, but it is not well described in the literature. In the present study, we used histological and functional approaches to conduct a detailed exploration of the model of vestibular lesions induced by transtympanic injection of sodium arsanilate in rats. The arsanilate-induced damage was restricted to the vestibular sensory organs without affecting the external ear, themore » oropharynx, or Scarpa's ganglion. This finding strongly supports the absence of diffusion of arsanilate into the external ear or Eustachian tubes, or through the eighth cranial nerve sheath leading to the brainstem. One of the striking observations of the present study is the complete restructuring of the sensory epithelia into a non sensory epithelial monolayer observed at 3 months after arsanilate application. This atrophy resembles the monolayer epithelia observed postmortem in the vestibular epithelia of patients with a history of lesioned vestibular deficits such as labyrinthectomy, antibiotic treatment, vestibular neuritis, or Ménière's disease. In cases of Ménière's disease, aminoglycosides, and platinum-based chemotherapy, vestibular hair cells are destroyed, regardless of the physiopathological process, as reproduced with the arsanilate model of vestibular lesion. These observations, together with those presented in this study of arsanilate vestibular toxicity, suggest that this atrophy process relies on a common mechanism of degeneration of the sensory epithelia.« less

PLCγ-activated signalling is essential for TrkB mediated sensory neuron structural plasticity

PubMed Central

2010-01-01

Background The vestibular system provides the primary input of our sense of balance and spatial orientation. Dysfunction of the vestibular system can severely affect a person's quality of life. Therefore, understanding the molecular basis of vestibular neuron survival, maintenance, and innervation of the target sensory epithelia is fundamental. Results Here we report that a point mutation at the phospholipase Cγ (PLCγ) docking site in the mouse neurotrophin tyrosine kinase receptor TrkB (Ntrk2) specifically impairs fiber guidance inside the vestibular sensory epithelia, but has limited effects on the survival of vestibular sensory neurons and growth of afferent processes toward the sensory epithelia. We also show that expression of the TRPC3 cation calcium channel, whose activity is known to be required for nerve-growth cone guidance induced by brain-derived neurotrophic factor (BDNF), is altered in these animals. In addition, we find that absence of the PLCγ mediated TrkB signalling interferes with the transformation of bouton type afferent terminals of vestibular dendrites into calyces (the largest synaptic contact of dendrites known in the mammalian nervous system) on type I vestibular hair cells; the latter are normally distributed in these mutants as revealed by an unaltered expression pattern of the potassium channel KCNQ4 in these cells. Conclusions These results demonstrate a crucial involvement of the TrkB/PLCγ-mediated intracellular signalling in structural aspects of sensory neuron plasticity. PMID:20932311

Expression of S100 beta in sensory and secretory cells of the vertebrate inner ear

NASA Technical Reports Server (NTRS)

Fermin, C. D.; Martin, D. S.

1995-01-01

We evaluated anti-S100 beta expression in the chick (Gallus domesticus) inner ear and determined that: 1) the monomer anti-S100 beta is expressed differentially in the vestibular and auditory perikarya; 2) expression of S100 beta in the afferent nerve terminals is time-related to synapse and myelin formation; 3) the expression of the dimer anti-S100 alpha alpha beta beta and monomer anti-S100 beta overlaps in most inner ear cell types. Most S100 alpha alpha beta beta positive cells express S100 beta, but S100 beta positive cells do not always express S100 alpha alpha beta beta. 4) the expression of S100 beta is diffused over the perikaryal cytoplasm and nuclei of the acoustic ganglia but is concentrated over the nuclei of the vestibular perikarya. 6) S100 beta is expressed in secretory cells, and it is co-localized with GABA in sensory cells. 7) Color thresholding objective quantitation indicates that the amount of S100 beta was higher (mean 22, SD +/- 4) at E19 than at E9 (mean 34, SD +/- 3) in afferent axons. 8) Moreover, S100 beta was unchanged between E11-E19 in the perikaryal cytoplasm, but did change over the nuclei. At E9, 74%, and at E21, 5% of vestibular perikarya were positive. The data suggest that S100 beta may be physically associated with neuronal and ionic controlling cells of the vertebrate inner ear, where it could provide a dual ionic and neurotrophic modulatory function.

Histone Deacetylase Inhibitor Induces the Expression of Select Epithelial Genes in Mouse Utricle Sensory Epithelia-Derived Progenitor Cells

PubMed Central

Wang, Jue

2014-01-01

Abstract Mouse utricle sensory epithelial cell–derived progenitor cells (MUCs), which have hair cell progenitor and mesenchymal features via epithelial-to-mesenchymal transition (EMT) as previously described, provide a potential approach for hair cell regeneration via cell transplantation. In this study, we treated MUCs with trichostatin A (TSA) to determine whether histone deacetylase inhibitor is able to stimulate the expression of epithelial genes in MUCs, an essential step for guiding mesenchymal-like MUCs to become sensory epithelial cells. After 72 h of TSA treatment, MUCs acquired epithelial-like features, which were indicated by increased expression of epithelial markers such as Cdh1, Krt18, and Dsp. Additionally, TSA decreased the expression of mesenchymal markers, including Zeb1, Zeb2, Snai1, and Snai2, and prosensory genes Lfng, Six1, and Dlx5. Moreover, the expression of the hair cell genes Atoh1 and Myo6 was increased in TSA-treated MUCs. We also observed significantly decreased expression of Hdac2 and Hdac3 in TSA-treated MUCs. However, no remarkable change was detected in protein expression using immunofluorescence, indicating that TSA-induced HDAC inhibition may contribute to the initial stage of the mesenchymal-to-epithelial phenotypic change. In the future, more work is needed to induce hair cell regeneration using inner ear tissue–derived progenitors to achieve an entire mesenchymal-to-epithelial transition. PMID:24945595

Inner Ear Drug Delivery for Auditory Applications

PubMed Central

Swan, Erin E. Leary; Mescher, Mark J.; Sewell, William F.; Tao, Sarah L.; Borenstein, Jeffrey T.

2008-01-01

Many inner ear disorders cannot be adequately treated by systemic drug delivery. A blood-cochlear barrier exists, similar physiologically to the blood-brain barrier, which limits the concentration and size of molecules able to leave the circulation and gain access to the cells of the inner ear. However, research in novel therapeutics and delivery systems has led to significant progress in the development of local methods of drug delivery to the inner ear. Intratympanic approaches, which deliver therapeutics to the middle ear, rely on permeation through tissue for access to the structures of the inner ear, whereas intracochlear methods are able to directly insert drugs into the inner ear. Innovative drug delivery systems to treat various inner ear ailments such as ototoxicity, sudden sensorineural hearing loss, autoimmune inner ear disease, and for preserving neurons and regenerating sensory cells are being explored. PMID:18848590

Developmental evolutionary biology of the vertebrate ear: conserving mechanoelectric transduction and developmental pathways in diverging morphologies

NASA Technical Reports Server (NTRS)

Fritzsch, B.; Beisel, K. W.; Bermingham, N. A.

2000-01-01

This brief overview shows that a start has been made to molecularly dissect vertebrate ear development and its evolutionary conservation to the development of the insect hearing organ. However, neither the patterning process of the ear nor the patterning process of insect sensory organs is sufficiently known at the moment to provide more than a first glimpse. Moreover, hardly anything is known about otocyst development of the cephalopod molluscs, another triploblast lineage that evolved complex 'ears'. We hope that the apparent conserved functional and cellular components present in the ciliated sensory neurons/hair cells will also be found in the genes required for vertebrate ear and insect sensory organ morphogenesis (Fig. 3). Likewise, we expect that homologous pre-patterning genes will soon be identified for the non-sensory cell development, which is more than a blocking of neuronal development through the Delta/Notch signaling system. Generation of the apparently unique ear could thus represent a multiplication of non-sensory cells by asymmetric and symmetric divisions as well as modification of existing patterning process by implementing novel developmental modules. In the final analysis, the vertebrate ear may come about by increasing the level of gene interactions in an already existing and highly conserved interactive cascade of bHLH genes. Since this was apparently achieved in all three lineages of triploblasts independently (Fig. 3), we now need to understand how much of the morphogenetic cascades are equally conserved across phyla to generate complex ears. The existing mutations in humans and mice may be able to point the direction of future research to understand the development of specific cell types and morphologies in the formation of complex arthropod, cephalopod, and vertebrate 'ears'.

Vitamin D receptor deficiency impairs inner ear development in zebrafish

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwon, Hye-Joo; Biology Department, Princess Nourah University, Riyadh 11671

The biological actions of vitamin D are largely mediated through binding to the vitamin D receptor (VDR), a member of the nuclear hormone receptor family, which regulates gene expression in a wide variety of tissues and cells. Mutations in VDR gene have been implicated in ear disorders (hearing loss and balance disorder) but the mechanisms are not well established. In this study, to investigate the role of VDR in inner ear development, morpholino-mediated gene knockdown approaches were used in zebrafish model system. Two paralogs for VDR, vdra and vdrb, have been identified in zebrafish. Knockdown of vdra had no effectmore » on ear development, whereas knockdown of vdrb displayed morphological ear defects including smaller otic vesicles with malformed semicircular canals and abnormal otoliths. Loss-of-vdrb resulted in down-regulation of pre-otic markers, pax8 and pax2a, indicating impairment of otic induction. Furthermore, zebrafish embryos lacking vdrb produced fewer sensory hair cells in the ears and showed disruption of balance and motor coordination. These data reveal that VDR signaling plays an important role in ear development. - Highlights: • VDR signaling is involved in ear development. • Knockdown of vdrb causes inner ear malformations during embryogenesis. • Knockdown of vdrb affects otic placode induction. • Knockdown of vdrb reduces the number of sensory hair cells in the inner ear. • Knockdown of vdrb disrupts balance and motor coordination.« less

A drop-tower experiment to determine the threshold of gravity for inducing motion sickness in fish

NASA Astrophysics Data System (ADS)

Anken, R. H.; Hilbig, R.

2004-01-01

It has been repeatedly shown earlier that some fish of a given batch reveal motion sickness (a kinetosis) at the transition from 1 g to microgravity. In the course of parabolic aircraft flight experiments, it has been demonstrated that kinetosis susceptibility is correlated with asymmetric inner ear otoliths (i.e., differently weighed statoliths on the right and the left side of the head) or with genetically predispositioned malformed cells within the sensory epithelia of the inner ear. Hitherto, the threshold of gravity perception for inducing kinetotic behavior as well as the relative importance of asymmetric otoliths versus malformed epithelia for kinetosis susceptibility has yet not been determined. The following experiment using the ZARM drop-tower facility in Bremen, Germany, is proposed to be carried out in order to answer the aforementioned questions. Larval cichlid fish ( Oreochromis mossambicus) will be kept in a camcorder-equipped centrifuge during the microgravity phases of the drops and thus receive various gravity environments ranging from 0.1 to 0.9 g. Videographed controls will be housed outside of the centrifuge receiving 0 g. Based on the video-recordings, animals will be grouped into kinetotically and normally swimming samples. Subsequently, otoliths will be dissected and their size and asymmetry will be measured. Further investigations will focus on the numerical quantification of inner ear supporting and sensory cells as well as on the quantification of inner ear carbonic anhydrase reactivity. A correlation between: (1) the results to be obtained concerning the g-loads inducing kinetosis and (2) the corresponding otolith asymmetry/morphology of sensory epithelia/carbonic anhydrase reactivity will further contribute to the understanding of the origin of kinetosis susceptibility. Besides an outline of the proposed principal experiments, the present study reports on a first series of drop-tower tests, which were undertaken to elucidate the

Determination of the threshold of gravity for inducing kinetosis in fish: A drop-tower experiment

NASA Astrophysics Data System (ADS)

Anken, Ralf H.; Hilbig, R.

2004-06-01

It has been repeatedly shown earlier that some fish of a given batch reveal motion sickness (a kinetosis) at the transition from 1g to microgravity. In the course of parabolic aircraft flight experiments, it has been demonstrated that kinetosis susceptibility is correlated with asymmetric inner ear otoliths (i.e., differently weighed statoliths on the right and the left side of the head) or with genetically predispositioned malformed cells within the sensory epithelia of the inner ear. Hitherto, the threshold of gravity perception for inducing kinetotic behaviour as well as the relative importance of asymmetric otoliths versus malformed epithelia for kinetosis susceptibility has yet not been determined. The following experiment using the ZARM droptower facility in Bremen, Germany, is proposed to be carried out in order to answer the aforementioned questions. Larval cichlid fish ( Oreochromis mossambicus) will be kept in a camcorder-equipped centrifuge during the microgravity phases of the drops and thus receive various gravity environments ranging from 0.1 to 0.9g. Videographed controls will be housed outside of the centrifuge receiving 0g. Based on the videorecordings, animals will be grouped into kinetotically and normally swimming samples. Subsequently, otoliths will be dissected and their size and asymmetry will be measured. Further investigations will focus on the numerical quantification of inner ear supporting and sensory cells as well as on the quantification of inner ear carbonic anhydrase reactivity. A correlation between (1) the results to be obtained concerning the g-loads inducing kinetosis and (2) the corresponding otolith asymmetry/morphology of sensory epithelia/carbonic anhydrase reactivity will further contribute to the understanding of the origin of kinetosis susceptibility. Besides an outline of the proposed principal experiments, the present study reports on a first series of drop-tower tests which were undertaken to elucidate the feasibility

[Lop ear - knife, tape, or nothing at all?].

PubMed

Klockars, Tuomas

2013-01-01

More than 200 different surgical techniques of correction of lop ear have been published. The operation is usually recommended to be performed at the age of six years or after. In addition, lop ear surgery involves risks, the most common complications being bleeding, infections, sensory alterations and scarring problems. Surgical preference and decision should always be based on realistic expectations of the patient or the parents, and prior to the decision they should have adequate information about the nature of the procedure and potential complications. Splint therapy of lop ear is possible for infants.

BONE MARROW MESENCHYMAL STEM CELLS ARE PROGENITORS IN VITRO FOR INNER EAR HAIR CELLS

PubMed Central

Jeon, Sang-Jun; Oshima, Kazuo; Heller, Stefan; Edge, Albert S.B.

2011-01-01

Stem cells have been demonstrated in the inner ear but they do not spontaneously divide to replace damaged sensory cells. Mesenchymal stem cells (MSC) from bone marrow have been reported to differentiate into multiple lineages including neurons, and we therefore asked whether MSCs could generate sensory cells. Overexpression of the prosensory transcription factor, Math1, in sensory epithelial precursor cells induced expression of myosin VIIa, espin, Brn3c, p27Kip, and jagged2, indicating differentiation to inner ear sensory cells. Some of the cells displayed F-actin positive protrusions in the morphology characteristic of hair cell stereociliary bundles. Hair cell markers were also induced by culture of mouse MSC-derived cells in contact with embryonic chick inner ear cells, and this induction was not due to a cell fusion event, because the chick hair cells could be identified with a chick-specific antibody and chick and mouse antigens were never found in the same cell. PMID:17113786

Developing an Ear Prosthesis Fabricated in Polyvinylidene Fluoride by a 3D Printer with Sensory Intrinsic Properties of Pressure and Temperature

PubMed Central

Suaste-Gómez, Ernesto; Rodríguez-Roldán, Grissel; Reyes-Cruz, Héctor; Terán-Jiménez, Omar

2016-01-01

An ear prosthesis was designed in 3D computer graphics software and fabricated using a 3D printing process of polyvinylidene fluoride (PVDF) for use as a hearing aid. In addition, the prosthesis response to pressure and temperature was observed. Pyroelectric and piezoelectric properties of this ear prosthesis were investigated using an astable multivibrator circuit, as changes in PVDF permittivity were observed according to variations of pressure and temperature. The results show that this prosthesis is reliable for use under different conditions of pressure (0 Pa to 16,350 Pa) and temperature (2 °C to 90 °C). The experimental results show an almost linear and inversely proportional behavior between the stimuli of pressure and temperature with the frequency response. This 3D-printed ear prosthesis is a promising tool and has a great potentiality in the biomedical engineering field because of its ability to generate an electrical potential proportional to pressure and temperature, and it is the first time that such a device has been processed by the additive manufacturing process (3D printing). More work needs to be carried out to improve the performance, such as electrical stimulation of the nervous system, thereby extending the purpose of a prosthesis to the area of sensory perception. PMID:26959026

Developing an Ear Prosthesis Fabricated in Polyvinylidene Fluoride by a 3D Printer with Sensory Intrinsic Properties of Pressure and Temperature.

PubMed

Suaste-Gómez, Ernesto; Rodríguez-Roldán, Grissel; Reyes-Cruz, Héctor; Terán-Jiménez, Omar

2016-03-04

An ear prosthesis was designed in 3D computer graphics software and fabricated using a 3D printing process of polyvinylidene fluoride (PVDF) for use as a hearing aid. In addition, the prosthesis response to pressure and temperature was observed. Pyroelectric and piezoelectric properties of this ear prosthesis were investigated using an astable multivibrator circuit, as changes in PVDF permittivity were observed according to variations of pressure and temperature. The results show that this prosthesis is reliable for use under different conditions of pressure (0 Pa to 16,350 Pa) and temperature (2 °C to 90 °C). The experimental results show an almost linear and inversely proportional behavior between the stimuli of pressure and temperature with the frequency response. This 3D-printed ear prosthesis is a promising tool and has a great potentiality in the biomedical engineering field because of its ability to generate an electrical potential proportional to pressure and temperature, and it is the first time that such a device has been processed by the additive manufacturing process (3D printing). More work needs to be carried out to improve the performance, such as electrical stimulation of the nervous system, thereby extending the purpose of a prosthesis to the area of sensory perception.

Immunolocalization of aquaporin CHIP in the guinea pig inner ear.

PubMed

Stanković, K M; Adams, J C; Brown, D

1995-12-01

Aquaporin CHIP (AQP-CHIP) is a water channel protein previously identified in red blood cells and water transporting epithelia. The inner ear is an organ of hearing and balance whose normal function depends critically on maintenance of fluid homeostasis. In this study, AQP-CHIP, or a close homologue, was found in specific cells of the inner ear, as assessed by immunocytochemistry with the use of affinity-purified polyclonal antibodies against AQP-CHIP.AQP-CHIP was predominantly found in fibrocytes in close association with bone, including most of the cells lining the bony labyrinth and in fibrocytes lining the endolymphatic duct and sac. AQP-CHIP-positive cells not directly apposing bone include cells under the basilar membrane, some type III fibrocytes of the spiral ligament, fibrocytes of the spiral limbus, and the trabecular perilymphatic tissue extending from the membranous to the bony labyrinth. AQP-CHIP was also found in the periosteum of the middle ear and cranial bones, as well as in chondrocytes of the oval window and stapes. The distribution of AQP-CHIP in the inner ear suggests that AQP-CHIP may have special significance for maintenance of bone and the basilar membrane, and for function of the spiral ligament.

Stem Cell Therapy for the Inner Ear

PubMed Central

Okano, Takayuki

2012-01-01

In vertebrates, perception of sound, motion, and balance is mediated through mechanosensory hair cells located within the inner ear. In mammals, hair cells are only generated during a short period of embryonic development. As a result, loss of hair cells as a consequence of injury, disease, or genetic mutation, leads to permanent sensory deficits. At present, cochlear implantation is the only option for profound hearing loss. However, outcomes are still variable and even the best implant cannot provide the acuity of a biological ear. The recent emergence of stem cell technology has the potential to open new approaches for hair cell regeneration. The goal of this review is to summarize the current state of inner ear stem cell research from a viewpoint of its clinical application for inner ear disorders to illustrate how complementary studies have the potential to promote and refine stem cell therapies for inner ear diseases. The review initially discusses our current understanding of the genetic pathways that regulate hair cell formation from inner ear progenitors during normal development. Subsequent sections discuss the possible use of endogenous inner ear stem cells to induce repair as well as the initial studies aimed at transplanting stem cells into the ear. PMID:22514095

ILDR1 null mice, a model of human deafness DFNB42, show structural aberrations of tricellular tight junctions and degeneration of auditory hair cells

PubMed Central

Morozko, Eva L.; Nishio, Ayako; Ingham, Neil J.; Chandra, Rashmi; Fitzgerald, Tracy; Martelletti, Elisa; Borck, Guntram; Wilson, Elizabeth; Riordan, Gavin P.; Wangemann, Philine; Forge, Andrew; Steel, Karen P.; Liddle, Rodger A.; Friedman, Thomas B.; Belyantseva, Inna A.

2015-01-01

In the mammalian inner ear, bicellular and tricellular tight junctions (tTJs) seal the paracellular space between epithelial cells. Tricellulin and immunoglobulin-like (Ig-like) domain containing receptor 1 (ILDR1, also referred to as angulin-2) localize to tTJs of the sensory and non-sensory epithelia in the organ of Corti and vestibular end organs. Recessive mutations of TRIC (DFNB49) encoding tricellulin and ILDR1 (DFNB42) cause human nonsyndromic deafness. However, the pathophysiology of DFNB42 deafness remains unknown. ILDR1 was recently reported to be a lipoprotein receptor mediating the secretion of the fat-stimulated cholecystokinin (CCK) hormone in the small intestine, while ILDR1 in EpH4 mouse mammary epithelial cells in vitro was shown to recruit tricellulin to tTJs. Here we show that two different mouse Ildr1 mutant alleles have early-onset severe deafness associated with a rapid degeneration of cochlear hair cells (HCs) but have a normal endocochlear potential. ILDR1 is not required for recruitment of tricellulin to tTJs in the cochlea in vivo; however, tricellulin becomes mislocalized in the inner ear sensory epithelia of ILDR1 null mice after the first postnatal week. As revealed by freeze-fracture electron microscopy, ILDR1 contributes to the ultrastructure of inner ear tTJs. Taken together, our data provide insight into the pathophysiology of human DFNB42 deafness and demonstrate that ILDR1 is crucial for normal hearing by maintaining the structural and functional integrity of tTJs, which are critical for the survival of auditory neurosensory HCs. PMID:25217574

Generation and characterization of Atoh1-Cre knock-in mouse line

PubMed Central

Yang, Hua; Xie, Xiaoling; Deng, Min; Chen, Xiaowei; Gan, Lin

2010-01-01

Summary Atoh1 encodes a basic helix-loop-helix (bHLH) transcription factor required for the development of the inner ear sensory epithelia, the dorsal spinal cord, brainstem, cerebellum, and intestinal secretory cells. In this study to create a genetic tool for the research on gene function in the ear sensory organs, we generated an Atoh1-Cre knock-in mouse line by replacing the entire Atoh1 coding sequences with the Cre coding sequences. Atoh1Cre/+mice were viable, fertile, and displayed no visible defects whereas the Atoh1Cre/Cremice died perinatally. The spatiotemporal activities of Cre recombinase were examined by crossing Atoh1-Cre mice with the R26R-lacZ conditional reporter mice. Atoh1-Cre activities were detected in the developing inner ear, the hindbrain, the spinal cord, and the intestine. In the inner ear, Atoh1-Cre activities were confined to the sensory organs in which lacZ expression is detected in nearly all of the hair cells and in many supporting cells. Thus, Atoh1-Cre mouse line serves as a useful tool for the functional study of genes in the inner ear. In addition, our results demonstrate that Atoh1 is expressed in the common progenitors destined for both hair and supporting cells. PMID:20533400

Ear Deformations Give Bats a Physical Mechanism for Fast Adaptation of Ultrasonic Beam Patterns

NASA Astrophysics Data System (ADS)

Gao, Li; Balakrishnan, Sreenath; He, Weikai; Yan, Zhen; Müller, Rolf

2011-11-01

A large number of mammals, including humans, have intricate outer ear shapes that diffract incoming sound in a direction- and frequency-specific manner. Through this physical process, the outer ear shapes encode sound-source information into the sensory signals from each ear. Our results show that horseshoe bats could dynamically control these diffraction processes through fast nonrigid ear deformations. The bats’ ear shapes can alter between extreme configurations in about 100 ms and thereby change their acoustic properties in ways that would suit different acoustic sensing tasks.

Three-dimensional Organotypic Cultures of Vestibular and Auditory Sensory Organs.

PubMed

Gnedeva, Ksenia; Hudspeth, A J; Segil, Neil

2018-06-01

The sensory organs of the inner ear are challenging to study in mammals due to their inaccessibility to experimental manipulation and optical observation. Moreover, although existing culture techniques allow biochemical perturbations, these methods do not provide a means to study the effects of mechanical force and tissue stiffness during development of the inner ear sensory organs. Here we describe a method for three-dimensional organotypic culture of the intact murine utricle and cochlea that overcomes these limitations. The technique for adjustment of a three-dimensional matrix stiffness described here permits manipulation of the elastic force opposing tissue growth. This method can therefore be used to study the role of mechanical forces during inner ear development. Additionally, the cultures permit virus-mediated gene delivery, which can be used for gain- and loss-of-function experiments. This culture method preserves innate hair cells and supporting cells and serves as a potentially superior alternative to the traditional two-dimensional culture of vestibular and auditory sensory organs.

Molecular evolution of the vertebrate mechanosensory cell and ear.

PubMed

Fritzsch, Bernd; Beisel, Kirk W; Pauley, Sarah; Soukup, Garrett

2007-01-01

The molecular basis of mechanosensation, mechanosensory cell development and mechanosensory organ development is reviewed with an emphasis on its evolution. In contrast to eye evolution and development, which apparently modified a genetic program through intercalation of genes between the master control genes on the top (Pax6, Eya1, Six1) of the hierarchy and the structural genes (rhodopsin) at the bottom, the as yet molecularly unknown mechanosensory channel precludes such a firm conclusion for mechanosensors. However, recent years have seen the identification of several structural genes which are involved in mechanosensory tethering and several transcription factors controlling mechanosensory cell and organ development; these warrant the interpretation of available data in very much the same fashion as for eye evolution: molecular homology combined with potential morphological parallelism. This assertion of molecular homology is strongly supported by recent findings of a highly conserved set of microRNAs that appear to be associated with mechanosensory cell development across phyla. The conservation of transcription factors and their regulators fits very well to the known or presumed mechanosensory specializations which can be mostly grouped as variations of a common cellular theme. Given the widespread distribution of the molecular ability to form mechanosensory cells, it comes as no surprise that structurally different mechanosensory organs evolved in different phyla, presenting a variation of a common theme specified by a conserved set of transcription factors in their cellular development. Within vertebrates and arthropods, some mechanosensory organs evolved into auditory organs, greatly increasing sensitivity to sound through modifications of accessory structures to direct sound to the specific sensory epithelia. However, while great attention has been paid to the evolution of these accessory structures in vertebrate fossils, comparatively less attention has

Changes in the Adult Vertebrate Auditory Sensory Epithelium After Trauma

PubMed Central

Oesterle, Elizabeth C.

2012-01-01

Auditory hair cells transduce sound vibrations into membrane potential changes, ultimately leading to changes in neuronal firing and sound perception. This review provides an overview of the characteristics and repair capabilities of traumatized auditory sensory epithelium in the adult vertebrate ear. Injured mammalian auditory epithelium repairs itself by forming permanent scars but is unable to regenerate replacement hair cells. In contrast, injured non-mammalian vertebrate ear generates replacement hair cells to restore hearing functions. Non-sensory support cells within the auditory epithelium play key roles in the repair processes. PMID:23178236

Responses of the ear to low frequency sounds, infrasound and wind turbines.

PubMed

Salt, Alec N; Hullar, Timothy E

2010-09-01

Infrasonic sounds are generated internally in the body (by respiration, heartbeat, coughing, etc) and by external sources, such as air conditioning systems, inside vehicles, some industrial processes and, now becoming increasingly prevalent, wind turbines. It is widely assumed that infrasound presented at an amplitude below what is audible has no influence on the ear. In this review, we consider possible ways that low frequency sounds, at levels that may or may not be heard, could influence the function of the ear. The inner ear has elaborate mechanisms to attenuate low frequency sound components before they are transmitted to the brain. The auditory portion of the ear, the cochlea, has two types of sensory cells, inner hair cells (IHC) and outer hair cells (OHC), of which the IHC are coupled to the afferent fibers that transmit "hearing" to the brain. The sensory stereocilia ("hairs") on the IHC are "fluid coupled" to mechanical stimuli, so their responses depend on stimulus velocity and their sensitivity decreases as sound frequency is lowered. In contrast, the OHC are directly coupled to mechanical stimuli, so their input remains greater than for IHC at low frequencies. At very low frequencies the OHC are stimulated by sounds at levels below those that are heard. Although the hair cells in other sensory structures such as the saccule may be tuned to infrasonic frequencies, auditory stimulus coupling to these structures is inefficient so that they are unlikely to be influenced by airborne infrasound. Structures that are involved in endolymph volume regulation are also known to be influenced by infrasound, but their sensitivity is also thought to be low. There are, however, abnormal states in which the ear becomes hypersensitive to infrasound. In most cases, the inner ear's responses to infrasound can be considered normal, but they could be associated with unfamiliar sensations or subtle changes in physiology. This raises the possibility that exposure to the

How minute sooglossid frogs hear without a middle ear.

PubMed

Boistel, Renaud; Aubin, Thierry; Cloetens, Peter; Peyrin, Françoise; Scotti, Thierry; Herzog, Philippe; Gerlach, Justin; Pollet, Nicolas; Aubry, Jean-François

2013-09-17

Acoustic communication is widespread in animals. According to the sensory drive hypothesis [Endler JA (1993) Philos Trans R Soc Lond B Biol Sci 340(1292):215-225], communication signals and perceptual systems have coevolved. A clear illustration of this is the evolution of the tetrapod middle ear, adapted to life on land. Here we report the discovery of a bone conduction-mediated stimulation of the ear by wave propagation in Sechellophryne gardineri, one of the world's smallest terrestrial tetrapods, which lacks a middle ear yet produces acoustic signals. Based on X-ray synchrotron holotomography, we measured the biomechanical properties of the otic tissues and modeled the acoustic propagation. Our models show how bone conduction enhanced by the resonating role of the mouth allows these seemingly deaf frogs to communicate effectively without a middle ear.

Human myosin VIIA responsible for the Usher 1B syndrome: a predicted membrane-associated motor protein expressed in developing sensory epithelia.

PubMed

Weil, D; Levy, G; Sahly, I; Levi-Acobas, F; Blanchard, S; El-Amraoui, A; Crozet, F; Philippe, H; Abitbol, M; Petit, C

1996-04-16

The gene encoding human myosin VIIA is responsible for Usher syndrome type III (USH1B), a disease which associates profound congenital sensorineural deafness, vestibular dysfunction, and retinitis pigmentosa. The reconstituted cDNA sequence presented here predicts a 2215 amino acid protein with a typical unconventional myosin structure. This protein is expected to dimerize into a two-headed molecule. The C terminus of its tail shares homology with the membrane-binding domain of the band 4.1 protein superfamily. The gene consists of 48 coding exons. It encodes several alternatively spliced forms. In situ hybridization analysis in human embryos demonstrates that the myosin VIIA gene is expressed in the pigment epithelium and the photoreceptor cells of the retina, thus indicating that both cell types may be involved in the USH1B retinal degenerative process. In addition, the gene is expressed in the human embryonic cochlear and vestibular neuroepithelia. We suggest that deafness and vestibular dysfunction in USH1B patients result from a defect in the morphogenesis of the inner ear sensory cell stereocilia.

Responses of the ear to low frequency sounds, infrasound and wind turbines

PubMed Central

Salt, Alec N.; Hullar, Timothy E.

2010-01-01

Infrasonic sounds are generated internally in the body (by respiration, heartbeat, coughing, etc) and by external sources, such as air conditioning systems, inside vehicles, some industrial processes and, now becoming increasingly prevalent, wind turbines. It is widely assumed that infrasound presented at an amplitude below what is audible has no influence on the ear. In this review, we consider possible ways that low frequency sounds, at levels that may or may not be heard, could influence the function of the ear. The inner ear has elaborate mechanisms to attenuate low frequency sound components before they are transmitted to the brain. The auditory portion of the ear, the cochlea, has two types of sensory cells, inner hair cells (IHC) and outer hair cells (OHC), of which the IHC are coupled to the afferent fibers that transmit “hearing” to the brain. The sensory stereocilia (“hairs”) on the IHC are “fluid coupled” to mechanical stimuli, so their responses depend on stimulus velocity and their sensitivity decreases as sound frequency is lowered. In contrast, the OHC are directly coupled to mechanical stimuli, so their input remains greater than for IHC at low frequencies. At very low frequencies the OHC are stimulated by sounds at levels below those that are heard. Although the hair cells in other sensory structures such as the saccule may be tuned to infrasonic frequencies, auditory stimulus coupling to these structures is inefficient so that they are unlikely to be influenced by airborne infrasound. Structures that are involved in endolymph volume regulation are also known to be influenced by infrasound, but their sensitivity is also thought to be low. There are, however, abnormal states in which the ear becomes hypersensitive to infrasound. In most cases, the inner ear’s responses to infrasound can be considered normal, but they could be associated with unfamiliar sensations or subtle changes in physiology. This raises the possibility that

Expression of Prox1 defines regions of the avian otocyst that give rise to sensory or neural cells

NASA Technical Reports Server (NTRS)

Stone, Jennifer S.; Shang, Jia-Lin; Tomarev, Stanislav

2003-01-01

The simple primordium of the inner ear (otocyst) differentiates into many cell types, including sensory neurons and hair cells. We examined expression of the divergent homeobox transcription factor, cProx1, during otocyst development in chickens. Nuclear cProx1 protein is not evident in the otic placode but emerges in the otic cup by stage 12. At stage 16, cProx1-positive nuclei are scattered continuously throughout the neuroepithelium, from anteroventral to posteromedial. These labeled cells are neural precursors; they express betaIII-tubulin and migrate to the cochleovestibular ganglion between stages 13 and 21. By stage 18, two areas develop a dense pattern of cProx1 expression in which every nucleus is labeled. These areas emerge at the anterior and posterior extremes of the band of scattered cProx1 expression and express the sensory markers cSerrate1 and Cath1 by stage 23. Four discrete patches of dense cProx1 expression appear by stage 23 that correspond to the future superior crista, lateral crista, saccular macula, and posterior crista, as confirmed by immunolabeling for hair cell antigen (HCA) by stage 29. The remaining sensory epithelia display a dense pattern of cProx1 expression and label for HCA by stage 29. In the basilar papilla, nuclear cProx1 expression is down-regulated in most hair cells by stage 37 and in many supporting cells by stage 40. Our findings show that regions of the otocyst that give rise to neurons or hair cells are distinguished by their relative density of cProx1-positive nuclei, and suggest a role for cProx1 in the genesis of these cell types.

Zebrafish models of human eye and inner ear diseases.

PubMed

Blanco-Sánchez, B; Clément, A; Phillips, J B; Westerfield, M

2017-01-01

Eye and inner ear diseases are the most common sensory impairments that greatly impact quality of life. Zebrafish have been intensively employed to understand the fundamental mechanisms underlying eye and inner ear development. The zebrafish visual and vestibulo-acoustic systems are very similar to these in humans, and although not yet mature, they are functional by 5days post-fertilization (dpf). In this chapter, we show how the zebrafish has significantly contributed to the field of biomedical research and how researchers, by establishing disease models and meticulously characterizing their phenotypes, have taken the first steps toward therapies. We review here models for (1) eye diseases, (2) ear diseases, and (3) syndromes affecting eye and/or ear. The use of new genome editing technologies and high-throughput screening systems should increase considerably the speed at which knowledge from zebrafish disease models is acquired, opening avenues for better diagnostics, treatments, and therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

Ultramicroscopic examination of the ovine tonsillar epithelia.

PubMed

Casteleyn, Christophe; Cornelissen, Maria; Simoens, Paul; Van den Broeck, Wim

2010-05-01

As solid morphological knowledge of ovine tonsillar epithelia might contribute to a better understanding of the pathogenesis of several diseases including prion diseases, the epithelia of all tonsils of 7 one-year-old Texel sheep were examined using scanning and transmission electron microscopy. Major parts of the pharyngeal and tubal tonsils were covered by pseudostratified columnar ciliated epithelia that were interrupted by patches of epithelium containing cells with densely packed microfolds or microvilli, and cells with both microvilli and cilia. Smaller parts were covered by either flattened polygonal cells with densely packed microvilli or microfolds, squamous epithelial cells, or patches of reticular epithelium. The palatine and paraepiglottic tonsils were mainly lined by squamous epithelial cells with apical microplicae or short knobs. Additionally, regions of reticular epithelium containing epithelial cells with apical microvilli were seen. The lingual tonsil was uniformly covered by a keratinized squamous epithelium and devoid of microvillous cells and patches of reticular epithelium. The rostral half of the tonsil of the soft palate was lined by a pseudostratified columnar ciliated epithelium with characteristics of the pharyngeal and tubal tonsils. The epithelium of the caudal part resembled the epithelia of the palatine and paraepiglottic tonsils. Putative M cells, mainly characterized by apical microvilli or microfolds and a close association with lymphoid cells, seem manifestly present on the nasopharyngeal tonsils. The reticular epithelium of the palatine and paraepiglottic tonsils also harbor cells with small apical microvilli. The exact nature of these presumptive M cells should, however, be elucidated in functional studies.

Cell proliferation and hair cell addition in the ear of the goldfish, Carassius auratus

NASA Technical Reports Server (NTRS)

Lanford, P. J.; Presson, J. C.; Popper, A. N.

1996-01-01

Cell proliferation and hair cell addition have not been studied in the ears of otophysan fish, a group of species who have specialized hearing capabilities. In this study we used the mitotic S-phase marker bromodeoxyuridine (BrdU) to identify proliferating cells in the ear of one otophysan species, Carassius auratus (the goldfish). Animals were sacrificed at 3 h or 5 days postinjection with BrdU and processed for immunocytochemistry. The results of the study show that cell proliferation occurs in all of the otic endorgans and results in the addition of new hair cells. BrdU-labeled cells were distributed throughout all epithelia, including the primary auditory endorgan (saccule), where hair cell phenotypes vary considerably along the rostrocaudal axis. This study lays the groundwork for our transmission electron microscopy study of proliferative cells in the goldfish ear (Presson et al., Hearing Research 100 (1996) 10-20) as well as future studies of hair cell development in this species. The ability to predict, based on epithelial location, the future phenotype of developing hair cells in the saccule of the goldfish make that endorgan a particularly powerful model system for the investigation of early hair cell differentiation.

Vitamin D receptor deficiency impairs inner ear development in zebrafish.

PubMed

Kwon, Hye-Joo

2016-09-16

The biological actions of vitamin D are largely mediated through binding to the vitamin D receptor (VDR), a member of the nuclear hormone receptor family, which regulates gene expression in a wide variety of tissues and cells. Mutations in VDR gene have been implicated in ear disorders (hearing loss and balance disorder) but the mechanisms are not well established. In this study, to investigate the role of VDR in inner ear development, morpholino-mediated gene knockdown approaches were used in zebrafish model system. Two paralogs for VDR, vdra and vdrb, have been identified in zebrafish. Knockdown of vdra had no effect on ear development, whereas knockdown of vdrb displayed morphological ear defects including smaller otic vesicles with malformed semicircular canals and abnormal otoliths. Loss-of-vdrb resulted in down-regulation of pre-otic markers, pax8 and pax2a, indicating impairment of otic induction. Furthermore, zebrafish embryos lacking vdrb produced fewer sensory hair cells in the ears and showed disruption of balance and motor coordination. These data reveal that VDR signaling plays an important role in ear development. Copyright © 2016 Elsevier Inc. All rights reserved.

Structure and functions of keratin proteins in simple, stratified, keratinized and cornified epithelia

PubMed Central

Bragulla, Hermann H; Homberger, Dominique G

2009-01-01

Historically, the term ‘keratin’ stood for all of the proteins extracted from skin modifications, such as horns, claws and hooves. Subsequently, it was realized that this keratin is actually a mixture of keratins, keratin filament-associated proteins and other proteins, such as enzymes. Keratins were then defined as certain filament-forming proteins with specific physicochemical properties and extracted from the cornified layer of the epidermis, whereas those filament-forming proteins that were extracted from the living layers of the epidermis were grouped as ‘prekeratins’ or ‘cytokeratins’. Currently, the term ‘keratin’ covers all intermediate filament-forming proteins with specific physicochemical properties and produced in any vertebrate epithelia. Similarly, the nomenclature of epithelia as cornified, keratinized or non-keratinized is based historically on the notion that only the epidermis of skin modifications such as horns, claws and hooves is cornified, that the non-modified epidermis is a keratinized stratified epithelium, and that all other stratified and non-stratified epithelia are non-keratinized epithelia. At this point in time, the concepts of keratins and of keratinized or cornified epithelia need clarification and revision concerning the structure and function of keratin and keratin filaments in various epithelia of different species, as well as of keratin genes and their modifications, in view of recent research, such as the sequencing of keratin proteins and their genes, cell culture, transfection of epithelial cells, immunohistochemistry and immunoblotting. Recently, new functions of keratins and keratin filaments in cell signaling and intracellular vesicle transport have been discovered. It is currently understood that all stratified epithelia are keratinized and that some of these keratinized stratified epithelia cornify by forming a Stratum corneum. The processes of keratinization and cornification in skin modifications are

Gravitational Neurobiology of Fish

NASA Astrophysics Data System (ADS)

Rahmann, H.; Anken, R. H.

In vertebrates (including man), altered gravitational environments such as weightlessness can induce malfunctions of the inner ears, based on irregular movements of the semicircular cristae or on dislocations of the inner ear otoliths from the corresponding sensory epithelia. This will lead to illusionary tilts, since the vestibular inputs are not confirmed by the other sensory organs, which results in an intersensory conflict. Vertebrates in orbit therefore face severe orientation problems. In humans, the intersensory conflict may additionally lead to a malaise, commonly referred to as space motion sickness (SMS), a kinetosis. During the first days at weightlessness, the orientation problems (and SMS) disappear, since the brain develops a new compensatory interpretation of the available sensory data. The present review reports on the neurobiological responses - particularly of fish - observed at altered gravitational states, concerning behaviour and neuroplastic reactivities. Recent investigations employing microgravity (spaceflight, parabolic aircraft flights, clinostat) and hyper-gravity (laboratory centrifuges as ground based research tools) yielded clues and insights into the understanding of the respective basic phenomena

Better late than never: effective air-borne hearing of toads delayed by late maturation of the tympanic middle ear structures.

PubMed

Womack, Molly C; Christensen-Dalsgaard, Jakob; Hoke, Kim L

2016-10-15

Most vertebrates have evolved a tympanic middle ear that enables effective hearing of airborne sound on land. Although inner ears develop during the tadpole stages of toads, tympanic middle ear structures are not complete until months after metamorphosis, potentially limiting the sensitivity of post-metamorphic juveniles to sounds in their environment. We tested the hearing of five species of toads to determine how delayed ear development impairs airborne auditory sensitivity. We performed auditory brainstem recordings to test the hearing of the toads and used micro-computed tomography and histology to relate the development of ear structures to hearing ability. We found a large (14-27 dB) increase in hearing sensitivity from 900 to 2500 Hz over the course of ear development. Thickening of the tympanic annulus cartilage and full ossification of the middle ear bone are associated with increased hearing ability in the final stages of ear maturation. Thus, juvenile toads are at a hearing disadvantage, at least in the high-frequency range, throughout much of their development, because late-forming ear elements are critical to middle ear function at these frequencies. We discuss the potential fitness consequences of late hearing development, although research directly addressing selective pressures on hearing sensitivity across ontogeny is lacking. Given that most vertebrate sensory systems function very early in life, toad tympanic hearing may be a sensory development anomaly. © 2016. Published by The Company of Biologists Ltd.

Sensitization to serum albumins in children allergic to cow's milk and epithelia.

PubMed

Vicente-Serrano, J; Caballero, M L; Rodríguez-Pérez, R; Carretero, P; Pérez, R; Blanco, J G; Juste, S; Moneo, I

2007-09-01

Patients with persistent milk allergy and specific immunoglobulin E (IgE) to bovine serum albumin (BSA) have a greater risk of rhinoconjunctivitis and asthma because of animal dander. To prove the cross-reactivity between serum albumin (SA) of different mammals in milk, meat, and epithelia and determine if heat treatment of meats decrease the allergenicity of albumins. The study was performed using SDS-PAGE and IgE-immunoblotting using sera from eight patients sensitized to milk, BSA, and animal danders. Sera from non-allergic and only animal dander allergic subjects served as a control. With one exception, all patients' sera recognized SA in different meats (beef, lamb, deer, and pork), epithelia (dog, cat, and cow), and cow's milk. Some patients even were only sensitized to SA in meat and epithelia. Danders' allergic only recognized other proteins in epithelia but not SA. No patients reacted to SA from heated meat extracts. Serum albumin is an important allergen involved in milk, meat, and epithelia allergy. The first contact with SA was through cow's milk and patients developed sensitization to epithelia SA even without direct contact with animals. Patients with both BSA and cow's milk allergy must avoid raw meats and furry pets.

CFTR is required for maximal transepithelial liquid transport in pig alveolar epithelia.

PubMed

Li, Xiaopeng; Comellas, Alejandro P; Karp, Philip H; Ernst, Sarah E; Moninger, Thomas O; Gansemer, Nicholas D; Taft, Peter J; Pezzulo, Alejandro A; Rector, Michael V; Rossen, Nathan; Stoltz, David A; McCray, Paul B; Welsh, Michael J; Zabner, Joseph

2012-07-01

A balance between alveolar liquid absorption and secretion is critical for maintaining optimal alveolar subphase liquid height and facilitating gas exchange in the alveolar space. However, the role of cystic fibrosis transmembrane regulator protein (CFTR) in this homeostatic process has remained elusive. Using a newly developed porcine model of cystic fibrosis, in which CFTR is absent, we investigated ion transport properties and alveolar liquid transport in isolated type II alveolar epithelial cells (T2AECs) cultured at the air-liquid interface. CFTR was distributed exclusively to the apical surface of cultured T2AECs. Alveolar epithelia from CFTR(-/-) pigs failed to increase liquid absorption in response to agents that increase cAMP, whereas cAMP-stimulated liquid absorption in CFTR(+/-) epithelia was similar to that in CFTR(+/+) epithelia. Expression of recombinant CFTR restored stimulated liquid absorption in CFTR(-/-) T2AECs but had no effect on CFTR(+/+) epithelia. In ex vivo studies of nonperfused lungs, stimulated liquid absorption was defective in CFTR(-/-) alveolar epithelia but similar between CFTR(+/+) and CFTR(+/-) epithelia. When epithelia were studied at the air-liquid interface, elevating cAMP levels increased subphase liquid height in CFTR(+/+) but not in CFTR(-/-) T2AECs. Our findings demonstrate that CFTR is required for maximal liquid absorption under cAMP stimulation, but it is not the rate-limiting factor. Furthermore, our data define a role for CFTR in liquid secretion by T2AECs. These insights may help to develop new treatment strategies for pulmonary edema and respiratory distress syndrome, diseases in which lung liquid transport is disrupted.

Rhesus Cochlear and Vestibular Functions Are Preserved After Inner Ear Injection of Saline Volume Sufficient for Gene Therapy Delivery.

PubMed

Dai, Chenkai; Lehar, Mohamed; Sun, Daniel Q; Rvt, Lani Swarthout; Carey, John P; MacLachlan, Tim; Brough, Doug; Staecker, Hinrich; Della Santina, Alexandra M; Hullar, Timothy E; Della Santina, Charles C

2017-08-01

reconstruction of computed tomography (CT) images of adult C57BL6 mouse, rat, rhesus macaque, and human temporal bones (N = 3 each). Injection was well tolerated by all animals, with eight of nine exhibiting no signs of disequilibrium and one animal exhibiting transient disequilibrium that resolved spontaneously by 24 h after surgery. Physiologic results at the final, 8-week post-injection measurement showed that injection was well tolerated. Compared to its pretreatment values, no treated ear's ABR threshold had worsened by more than 5 dB at any stimulus frequency; distortion product otoacoustic emissions remained detectable above the noise floor for every treated ear (mean, SD and maximum deviation from baseline: -1.3, 9.0, and -18 dB, respectively); and no animal exhibited a reduction of more than 3 % in vestibulo-ocular reflex gain during high-acceleration, whole-body, passive yaw rotations in darkness toward the treated side. All control ears and all operated ears with definite histologic evidence of injection through the intended site showed similar findings, with intact hair cells in all five inner ear sensory epithelia and intact auditory/vestibular neurons. The relative volumes of mouse, rat, rhesus, and human inner ears as measured by CT were (mean ± SD) 2.5 ± 0.1, 5.5 ± 0.4, 59.4 ± 4.7 and 191.1 ± 4.7 μL. These results indicate that injection of PBSV at volumes sufficient for gene therapy delivery can be accomplished without destruction of inner ear structures required for hearing and vestibular sensation.

Electrotactile and vibrotactile displays for sensory substitution systems

NASA Technical Reports Server (NTRS)

Kaczmarek, Kurt A.; Webster, John G.; Bach-Y-rita, Paul; Tompkins, Willis J.

1991-01-01

Sensory substitution systems provide their users with environmental information through a human sensory channel (eye, ear, or skin) different from that normally used or with the information processed in some useful way. The authors review the methods used to present visual, auditory, and modified tactile information to the skin and discuss present and potential future applications of sensory substitution, including tactile vision substitution (TVS), tactile auditory substitution, and remote tactile sensing or feedback (teletouch). The relevant sensory physiology of the skin, including the mechanisms of normal touch and the mechanisms and sensations associated with electrical stimulation of the skin using surface electrodes (electrotactile, or electrocutaneous, stimulation), is reviewed. The information-processing ability of the tactile sense and its relevance to sensory substitution is briefly summarized. The limitations of current tactile display technologies are discussed.

Comparative biology of rAAV transduction in ferret, pig and human airway epithelia.

PubMed

Liu, X; Luo, M; Guo, C; Yan, Z; Wang, Y; Engelhardt, J F

2007-11-01

Differences between rodent and human airway cell biology have made it difficult to translate recombinant adeno-associated virus (rAAV)-mediated gene therapies to the lung for cystic fibrosis (CF). As new ferret and pig models for CF become available, knowledge about host cell/vector interactions in these species will become increasingly important for testing potential gene therapies. To this end, we have compared the transduction biology of three rAAV serotypes (AAV1, 2 and 5) in human, ferret, pig and mouse-polarized airway epithelia. Our results indicate that apical transduction of ferret and pig airway epithelia with these rAAV serotypes closely mirrors that observed in human epithelia (rAAV1>rAAV2 congruent withrAAV5), while transduction of mouse epithelia was significantly different (rAAV1>rAAV5>rAAV2). Similarly, ferret, pig and human epithelia also shared serotype-specific differences in the polarity (apical vs basolateral) and proteasome dependence of rAAV transduction. Despite these parallels, N-linked sialic acid receptors were required for rAAV1 and rAAV5 transduction of human and mouse airway epithelia, but not ferret or pig airway epithelia. Hence, although the airway tropisms of rAAV serotypes 1, 2 and 5 are conserved better among ferret, pig and human as compared to mouse, viral receptors/co-receptors appear to maintain considerable species diversity.

Precancerous esophageal epithelia are associated with significantly increased scattering coefficients

PubMed Central

Su, Jing-Wei; Lin, Yang-Hsien; Chiang, Chun-Ping; Lee, Jang-Ming; Hsieh, Chao-Mao; Hsieh, Min-Shu; Yang, Pei-Wen; Wang, Chen-Ping; Tseng, Ping-Huei; Lee, Yi-Chia; Sung, Kung-Bin

2015-01-01

The progression of epithelial precancers into cancer is accompanied by changes of tissue and cellular structures in the epithelium. Correlations between the structural changes and scattering coefficients of esophageal epithelia were investigated using quantitative phase images and the scattering-phase theorem. An ex vivo study of 14 patients demonstrated that the average scattering coefficient of precancerous epithelia was 37.8% higher than that of normal epithelia from the same patient. The scattering coefficients were highly correlated with morphological features including the cell density and the nuclear-to-cytoplasmic ratio. A high interpatient variability in scattering coefficients was observed and suggests identifying precancerous lesions based on the relative change in scattering coefficients. PMID:26504630

Evolution and development of the vertebrate ear

NASA Technical Reports Server (NTRS)

Fritzsch, B.; Beisel, K. W.

2001-01-01

This review outlines major aspects of development and evolution of the ear, specifically addressing issues of cell fate commitment and the emerging molecular governance of these decisions. Available data support the notion of homology of subsets of mechanosensors across phyla (proprioreceptive mechanosensory neurons in insects, hair cells in vertebrates). It is argued that this conservation is primarily related to the specific transducing environment needed to achieve mechanosensation. Achieving this requires highly conserved transcription factors that regulate the expression of the relevant structural genes for mechanosensory transduction. While conserved at the level of some cell fate assignment genes (atonal and its mammalian homologue), the ear has also radically reorganized its development by implementing genes used for cell fate assignment in other parts of the developing nervous systems (e.g., neurogenin 1) and by evolving novel sets of genes specifically associated with the novel formation of sensory neurons that contact hair cells (neurotrophins and their receptors). Numerous genes have been identified that regulate morphogenesis, but there is only one common feature that emerges at the moment: the ear appears to have co-opted genes from a large variety of other parts of the developing body (forebrain, limbs, kidneys) and establishes, in combination with existing transcription factors, an environment in which those genes govern novel, ear-related morphogenetic aspects. The ear thus represents a unique mix of highly conserved developmental elements combined with co-opted and newly evolved developmental elements.

Forensic discrimination of vaginal epithelia by DNA methylation analysis through pyrosequencing.

PubMed

Antunes, Joana; Silva, Deborah S B S; Balamurugan, Kuppareddi; Duncan, George; Alho, Clarice S; McCord, Bruce

2016-10-01

The accurate identification of body fluids from crime scenes can aid in the discrimination between criminal and innocent intent. This research aimed to determine if the levels of DNA methylation in the locus PFN3A could be used to discriminate vaginal epithelia from other body fluids. In this work we bisulfite-modified and amplified DNA samples from blood, saliva, semen, and vaginal epithelia using primers for PFN3A. Through pyrosequencing we were able to show that vaginal epithelia present distinct methylation levels when compared to other body fluids. Mixtures of different body fluids present methylation values that correlate with single-source body fluid samples and the primers for PFN3A are specific for primates. This report successfully demonstrated that the analysis of methylation in the PFN3A locus can be used for vaginal epithelia discrimination in forensic samples. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Biophysical Model of Ion Transport across Human Respiratory Epithelia Allows Quantification of Ion Permeabilities

PubMed Central

Garcia, Guilherme J.M.; Boucher, Richard C.; Elston, Timothy C.

2013-01-01

Lung health and normal mucus clearance depend on adequate hydration of airway surfaces. Because transepithelial osmotic gradients drive water flows, sufficient hydration of the airway surface liquid depends on a balance between ion secretion and absorption by respiratory epithelia. In vitro experiments using cultures of primary human nasal epithelia and human bronchial epithelia have established many of the biophysical processes involved in airway surface liquid homeostasis. Most experimental studies, however, have focused on the apical membrane, despite the fact that ion transport across respiratory epithelia involves both cellular and paracellular pathways. In fact, the ion permeabilities of the basolateral membrane and paracellular pathway remain largely unknown. Here we use a biophysical model for water and ion transport to quantify ion permeabilities of all pathways (apical, basolateral, paracellular) in human nasal epithelia cultures using experimental (Ussing Chamber and microelectrode) data reported in the literature. We derive analytical formulas for the steady-state short-circuit current and membrane potential, which are for polarized epithelia the equivalent of the Goldman-Hodgkin-Katz equation for single isolated cells. These relations allow parameter estimation to be performed efficiently. By providing a method to quantify all the ion permeabilities of respiratory epithelia, the model may aid us in understanding the physiology that regulates normal airway surface hydration. PMID:23442922

Effectiveness of Ear Splint Therapy for Ear Deformities

PubMed Central

2017-01-01

Objective To present our experience with ear splint therapy for babies with ear deformities, and thereby demonstrate that this therapy is an effective and safe intervention without significant complications. Methods This was a retrospective study of 54 babies (35 boys and 19 girls; 80 ears; age ≤3 months) with ear deformities who had received ear splint therapy at the Center for Torticollis, Department of Physical Medicine and Rehabilitation, Ajou University Hospital between December 2014 and February 2016. Before the initiation of ear splint therapy, ear deformities were classified with reference to the standard terminology. We compared the severity of ear deformity before and after ear splint therapy by using the physician's ratings. We also compared the physician's ratings and the caregiver's ratings on completion of ear splint therapy. Results Among these 54 babies, 41 children (58 ears, 72.5%) completed the ear splint therapy. The mean age at initiation of therapy was 52.91±18.26 days and the treatment duration was 44.27±32.06 days. Satyr ear, forward-facing ear lobe, Darwinian notch, overfolded ear, and cupped ear were the five most common ear deformities. At the completion of therapy, the final physician's ratings of ear deformities were significantly improved compared to the initial ratings (8.28±1.44 vs. 2.51±0.92; p<0.001). There was no significant difference between the physician's ratings and the caregiver's ratings at the completion of ear splint therapy (8.28±1.44 vs. 8.0±1.61; p=0.297). Conclusion We demonstrated that ear splint therapy significantly improved ear deformities in babies, as measured by quantitative rating scales. Ear splint therapy is an effective and safe intervention for babies with ear deformities. PMID:28289646

Biophysical model of ion transport across human respiratory epithelia allows quantification of ion permeabilities.

PubMed

Garcia, Guilherme J M; Boucher, Richard C; Elston, Timothy C

2013-02-05

Lung health and normal mucus clearance depend on adequate hydration of airway surfaces. Because transepithelial osmotic gradients drive water flows, sufficient hydration of the airway surface liquid depends on a balance between ion secretion and absorption by respiratory epithelia. In vitro experiments using cultures of primary human nasal epithelia and human bronchial epithelia have established many of the biophysical processes involved in airway surface liquid homeostasis. Most experimental studies, however, have focused on the apical membrane, despite the fact that ion transport across respiratory epithelia involves both cellular and paracellular pathways. In fact, the ion permeabilities of the basolateral membrane and paracellular pathway remain largely unknown. Here we use a biophysical model for water and ion transport to quantify ion permeabilities of all pathways (apical, basolateral, paracellular) in human nasal epithelia cultures using experimental (Ussing Chamber and microelectrode) data reported in the literature. We derive analytical formulas for the steady-state short-circuit current and membrane potential, which are for polarized epithelia the equivalent of the Goldman-Hodgkin-Katz equation for single isolated cells. These relations allow parameter estimation to be performed efficiently. By providing a method to quantify all the ion permeabilities of respiratory epithelia, the model may aid us in understanding the physiology that regulates normal airway surface hydration. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Adenovirus Vectors Target Several Cell Subtypes of Mammalian Inner Ear In Vivo

PubMed Central

Li, Wenyan; Shen, Jun

2016-01-01

Mammalian inner ear harbors diverse cell types that are essential for hearing and balance. Adenovirus is one of the major vectors to deliver genes into the inner ear for functional studies and hair cell regeneration. To identify adenovirus vectors that target specific cell subtypes in the inner ear, we studied three adenovirus vectors, carrying a reporter gene encoding green fluorescent protein (GFP) from two vendors or with a genome editing gene Cre recombinase (Cre), by injection into postnatal days 0 (P0) and 4 (P4) mouse cochlea through scala media by cochleostomy in vivo. We found three adenovirus vectors transduced mouse inner ear cells with different specificities and expression levels, depending on the type of adenoviral vectors and the age of mice. The most frequently targeted region was the cochlear sensory epithelium, including auditory hair cells and supporting cells. Adenovirus with GFP transduced utricular supporting cells as well. This study shows that adenovirus vectors are capable of efficiently and specifically transducing different cell types in the mammalian inner ear and provides useful tools to study inner ear gene function and to evaluate gene therapy to treat hearing loss and vestibular dysfunction. PMID:28116172

Role of skeletal muscle in ear development.

PubMed

Rot, Irena; Baguma-Nibasheka, Mark; Costain, Willard J; Hong, Paul; Tafra, Robert; Mardesic-Brakus, Snjezana; Mrduljas-Djujic, Natasa; Saraga-Babic, Mirna; Kablar, Boris

2017-10-01

The current paper is a continuation of our work described in Rot and Kablar, 2010. Here, we show lists of 10 up- and 87 down-regulated genes obtained by a cDNA microarray analysis that compared developing Myf5-/-:Myod-/- (and Mrf4-/-) petrous part of the temporal bone, containing middle and inner ear, to the control, at embryonic day 18.5. Myf5-/-:Myod-/- fetuses entirely lack skeletal myoblasts and muscles. They are unable to move their head, which interferes with the perception of angular acceleration. Previously, we showed that the inner ear areas most affected in Myf5-/-:Myod-/- fetuses were the vestibular cristae ampullaris, sensitive to angular acceleration. Our finding that the type I hair cells were absent in the mutants' cristae was further used here to identify a profile of genes specific to the lacking cell type. Microarrays followed by a detailed consultation of web-accessible mouse databases allowed us to identify 6 candidate genes with a possible role in the development of the inner ear sensory organs: Actc1, Pgam2, Ldb3, Eno3, Hspb7 and Smpx. Additionally, we searched for human homologues of the candidate genes since a number of syndromes in humans have associated inner ear abnormalities. Mutations in one of our candidate genes, Smpx, have been reported as the cause of X-linked deafness in humans. Our current study suggests an epigenetic role that mechanical, and potentially other, stimuli originating from muscle, play in organogenesis, and offers an approach to finding novel genes responsible for altered inner ear phenotypes.

Structural centrosome aberrations sensitize polarized epithelia to basal cell extrusion.

PubMed

Ganier, Olivier; Schnerch, Dominik; Nigg, Erich A

2018-06-01

Centrosome aberrations disrupt tissue architecture and may confer invasive properties to cancer cells. Here we show that structural centrosome aberrations, induced by overexpression of either Ninein-like protein (NLP) or CEP131/AZI1, sensitize polarized mammalian epithelia to basal cell extrusion. While unperturbed epithelia typically dispose of damaged cells through apical dissemination into luminal cavities, certain oncogenic mutations cause a switch in directionality towards basal cell extrusion, raising the potential for metastatic cell dissemination. Here we report that NLP-induced centrosome aberrations trigger the preferential extrusion of damaged cells towards the basal surface of epithelial monolayers. This switch in directionality from apical to basal dissemination coincides with a profound reorganization of the microtubule cytoskeleton, which in turn prevents the contractile ring repositioning that is required to support extrusion towards the apical surface. While the basal extrusion of cells harbouring NLP-induced centrosome aberrations requires exogenously induced cell damage, structural centrosome aberrations induced by excess CEP131 trigger the spontaneous dissemination of dying cells towards the basal surface from MDCK cysts. Thus, similar to oncogenic mutations, structural centrosome aberrations can favour basal extrusion of damaged cells from polarized epithelia. Assuming that additional mutations may promote cell survival, this process could sensitize epithelia to disseminate potentially metastatic cells. © 2018 The Authors.

The plastic ear and perceptual relearning in auditory spatial perception

PubMed Central

Carlile, Simon

2014-01-01

The auditory system of adult listeners has been shown to accommodate to altered spectral cues to sound location which presumably provides the basis for recalibration to changes in the shape of the ear over a life time. Here we review the role of auditory and non-auditory inputs to the perception of sound location and consider a range of recent experiments looking at the role of non-auditory inputs in the process of accommodation to these altered spectral cues. A number of studies have used small ear molds to modify the spectral cues that result in significant degradation in localization performance. Following chronic exposure (10–60 days) performance recovers to some extent and recent work has demonstrated that this occurs for both audio-visual and audio-only regions of space. This begs the questions as to the teacher signal for this remarkable functional plasticity in the adult nervous system. Following a brief review of influence of the motor state in auditory localization, we consider the potential role of auditory-motor learning in the perceptual recalibration of the spectral cues. Several recent studies have considered how multi-modal and sensory-motor feedback might influence accommodation to altered spectral cues produced by ear molds or through virtual auditory space stimulation using non-individualized spectral cues. The work with ear molds demonstrates that a relatively short period of training involving audio-motor feedback (5–10 days) significantly improved both the rate and extent of accommodation to altered spectral cues. This has significant implications not only for the mechanisms by which this complex sensory information is encoded to provide spatial cues but also for adaptive training to altered auditory inputs. The review concludes by considering the implications for rehabilitative training with hearing aids and cochlear prosthesis. PMID:25147497

Localization of soluble guanylate cyclase activity in the guinea pig inner ear.

PubMed

Takumida, M; Anniko, M; Popa, R; Zhang, D M

2000-01-01

The aim of this study was to characterize the nitric oxide (NO) receptor soluble guanylate cyclase (sGC), to determine the cells targeted by NO and to elucidate the function of the NO/cGMP pathway in the inner ear. sGC activity in the inner ear was localized by immunohistochemical detection of NO-stimulated cGMP. Soluble guanylate cyclase activity in the cochlea was detected in the nerve endings underneath the outer and inner hair cells, supporting cells, stria vascularis and vessels. In the vestibular organs, sGC activity was detected in the cytoplasm of sensory cells, nerve fibres, dark cells and transitional cells and vessels. These findings suggest that the NO/cGMP pathway may be involved in regulatory processes in neurotransmission, blood flow and inner ear fluid homeostasis.

A review of gene delivery and stem cell based therapies for regenerating inner ear hair cells.

PubMed

Devarajan, Keerthana; Staecker, Hinrich; Detamore, Michael S

2011-09-13

Sensory neural hearing loss and vestibular dysfunction have become the most common forms of sensory defects, affecting millions of people worldwide. Developing effective therapies to restore hearing loss is challenging, owing to the limited regenerative capacity of the inner ear hair cells. With recent advances in understanding the developmental biology of mammalian and non-mammalian hair cells a variety of strategies have emerged to restore lost hair cells are being developed. Two predominant strategies have developed to restore hair cells: transfer of genes responsible for hair cell genesis and replacement of missing cells via transfer of stem cells. In this review article, we evaluate the use of several genes involved in hair cell regeneration, the advantages and disadvantages of the different viral vectors employed in inner ear gene delivery and the insights gained from the use of embryonic, adult and induced pluripotent stem cells in generating inner ear hair cells. Understanding the role of genes, vectors and stem cells in therapeutic strategies led us to explore potential solutions to overcome the limitations associated with their use in hair cell regeneration.

Probing the Xenopus laevis inner ear transcriptome for biological function

PubMed Central

2012-01-01

Background The senses of hearing and balance depend upon mechanoreception, a process that originates in the inner ear and shares features across species. Amphibians have been widely used for physiological studies of mechanotransduction by sensory hair cells. In contrast, much less is known of the genetic basis of auditory and vestibular function in this class of animals. Among amphibians, the genus Xenopus is a well-characterized genetic and developmental model that offers unique opportunities for inner ear research because of the amphibian capacity for tissue and organ regeneration. For these reasons, we implemented a functional genomics approach as a means to undertake a large-scale analysis of the Xenopus laevis inner ear transcriptome through microarray analysis. Results Microarray analysis uncovered genes within the X. laevis inner ear transcriptome associated with inner ear function and impairment in other organisms, thereby supporting the inclusion of Xenopus in cross-species genetic studies of the inner ear. The use of gene categories (inner ear tissue; deafness; ion channels; ion transporters; transcription factors) facilitated the assignment of functional significance to probe set identifiers. We enhanced the biological relevance of our microarray data by using a variety of curation approaches to increase the annotation of the Affymetrix GeneChip® Xenopus laevis Genome array. In addition, annotation analysis revealed the prevalence of inner ear transcripts represented by probe set identifiers that lack functional characterization. Conclusions We identified an abundance of targets for genetic analysis of auditory and vestibular function. The orthologues to human genes with known inner ear function and the highly expressed transcripts that lack annotation are particularly interesting candidates for future analyses. We used informatics approaches to impart biologically relevant information to the Xenopus inner ear transcriptome, thereby addressing the

Classification of Newborn Ear Malformations and their Treatment with the EarWell Infant Ear Correction System.

PubMed

Daniali, Lily N; Rezzadeh, Kameron; Shell, Cheryl; Trovato, Matthew; Ha, Richard; Byrd, H Steve

2017-03-01

A single practice's treatment protocol and outcomes following molding therapy on newborn ear deformations and malformations with the EarWell Infant Ear Correction System were reviewed. A classification system for grading the severity of constricted ear malformations was created on the basis of anatomical findings. A retrospective chart/photograph review of a consecutive series of infants treated with the EarWell System from 2011 to 2014 was undertaken. The infants were placed in either deformation or malformation groups. Three classes of malformation were identified. Data regarding treatment induction, duration of treatment, and quality of outcome were collected for all study patients. One hundred seventy-five infant ear malformations and 303 infant ear deformities were treated with the EarWell System. The average age at initiation of treatment was 12 days; the mean duration of treatment was 37 days. An average of six office visits was required. Treated malformations included constricted ears [172 ears (98 percent)] and cryptotia [three ears (2 percent)]. Cup ear (34 ears) was considered a constricted malformation, in contrast to the prominent ear deformity. Constricted ears were assigned to one of three classes, with each subsequent class indicating increasing severity: class I, 77 ears (45 percent); class II, 81 ears (47 percent); and class III, 14 ears (8 percent). Molding therapy with the EarWell System reduced the severity by an average of 1.2 points (p < 0.01). Complications included minor superficial excoriations and abrasions. The EarWell System was shown to be effective in eliminating or reducing the need for surgery in all but the most severe malformations. Therapeutic, IV.

Adipose-derived stromal cells enhance auditory neuron survival in an animal model of sensory hearing loss.

PubMed

Schendzielorz, Philipp; Vollmer, Maike; Rak, Kristen; Wiegner, Armin; Nada, Nashwa; Radeloff, Katrin; Hagen, Rudolf; Radeloff, Andreas

2017-10-01

A cochlear implant (CI) is an electronic prosthesis that can partially restore speech perception capabilities. Optimum information transfer from the cochlea to the central auditory system requires a proper functioning auditory nerve (AN) that is electrically stimulated by the device. In deafness, the lack of neurotrophic support, normally provided by the sensory cells of the inner ear, however, leads to gradual degeneration of auditory neurons with undesirable consequences for CI performance. We evaluated the potential of adipose-derived stromal cells (ASCs) that are known to produce neurotrophic factors to prevent neural degeneration in sensory hearing loss. For this, co-cultures of ASCs with auditory neurons have been studied, and autologous ASC transplantation has been performed in a guinea pig model of gentamicin-induced sensory hearing loss. In vitro ASCs were neuroprotective and considerably increased the neuritogenesis of auditory neurons. In vivo transplantation of ASCs into the scala tympani resulted in an enhanced survival of auditory neurons. Specifically, peripheral AN processes that are assumed to be the optimal activation site for CI stimulation and that are particularly vulnerable to hair cell loss showed a significantly higher survival rate in ASC-treated ears. ASC transplantation into the inner ear may restore neurotrophic support in sensory hearing loss and may help to improve CI performance by enhanced AN survival. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

New insights into the brain, braincase, and ear region of tyrannosaurs (Dinosauria, Theropoda), with implications for sensory organization and behavior.

PubMed

Witmer, Lawrence M; Ridgely, Ryan C

2009-09-01

The braincase region of tyrannosaurs was investigated to provide insights on anatomical attributes relevant to inferences of sensory biology and behavior. CT scanning focused on three specimens of Tyrannosaurus rex, a juvenile Gorgosaurus, and the controversial Cleveland skull (CMNH 7541). Analysis shows that the cerebral hemispheres were enlarged, but conflicting information on the optic lobes suggests that brain conformation was not fully avian. Previous estimates of olfactory bulb size for T. rex were much too large, but even the corrected sizes are relatively larger than other theropods, suggesting that odor detection was indeed of particular importance to tyrannosaurs. The inner ears show a number of coelurosaurian traits, such as elongate and rounded and rostral, lateral semicircular canals, and incipient twisting of the common crus, which we interpret to be related to enhanced reflexes coordinating rapid eye and head movements. The cochlea is elongate, which, coupled with the finding of extensive tympanic pneumaticity, supports the inference of behavioral emphasis of low-frequency sounds. Three main groups of sinuses pneumatized the braincase, and there are a number of perhaps systematically relevant differences. Orientation of the endosseous labyrinth reveals that alert head postures of T. rex and Gorgosaurus were somewhat depressed below the horizontal, but the Cleveland skull had a very strongly down-turned posture. It is concluded that tyrannosaur sensory biology is consistent with their predatory coelurosaurian heritage, with emphasis on relatively quick, coordinated eye and head movements, and probably sensitive low-frequency hearing; tyrannosaurs apomorphically enhanced their olfactory apparatus. The taxonomic status of the Cleveland skull remains unresolved. (c) 2009 Wiley-Liss, Inc.

Anatomical influences on internally coupled ears in reptiles.

PubMed

Young, Bruce A

2016-10-01

Many reptiles, and other vertebrates, have internally coupled ears in which a patent anatomical connection allows pressure waves generated by the displacement of one tympanic membrane to propagate (internally) through the head and, ultimately, influence the displacement of the contralateral tympanic membrane. The pattern of tympanic displacement caused by this internal coupling can give rise to novel sensory cues. The auditory mechanics of reptiles exhibit more anatomical variation than in any other vertebrate group. This variation includes structural features such as diverticula and septa, as well as coverings of the tympanic membrane. Many of these anatomical features would likely influence the functional significance of the internal coupling between the tympanic membranes. Several of the anatomical components of the reptilian internally coupled ear are under active motor control, suggesting that in some reptiles the auditory system may be more dynamic than previously recognized.

Ear Infection (Middle Ear)

MedlinePlus

... secretions from the middle ear Swelling, inflammation and mucus in the eustachian tubes from an upper respiratory ... your baby for at least six months. Breast milk contains antibodies that may offer protection from ear ...

Ear surgery techniques results on hearing threshold improvement

PubMed Central

Mokhtarinejad, Farhad; Pour, Saeed Soheili; Nilforoush, Mohammad Hussein; Sepehrnejad, Mahsa; Mirelahi, Susan

2013-01-01

Background: Bone conduction (BC) threshold depression is not always by means of sensory neural hearing loss and sometimes it is an artifact caused by middle ear pathologies and ossicular chain problems. In this research, the influences of ear surgeries on bone conduction were evaluated. Materials and Methods: This study was conducted as a clinical trial study. The ear surgery performed on 83 patients classified in four categories: Stapedectomy, tympanomastoid surgery and ossicular reconstruction partially or totally; Partial Ossicular Replacement Prosthesis (PORP) and Total Ossicular Replacement Prosthesis (TORP). Bone conduction thresholds assessed in frequencies of 250, 500, 1000, 2000 and 4000 Hz pre and post the surgery. Results: In stapedectomy group, the average of BC threshold in all frequencies improved approximately 6 dB in frequency of 2000 Hz. In tympanomastoid group, BC threshold in the frequency of 500, 1000 and 2000 Hz changed 4 dB (P-value < 0.05). Moreover, In the PORP group, 5 dB enhancement was seen in 1000 and 2000 Hz. In TORP group, the results confirmed that BC threshold improved in all frequencies especially at 4000 Hz about 6.5 dB. Conclusion: In according to results of this study, BC threshold shift was seen after several ear surgeries such as stapedectomy, tympanoplasty, PORP and TORP. The average of BC improvement was approximately 5 dB. It must be considered that BC depression might happen because of ossicular chain problems. Therefore; by resolving middle ear pathologies, the better BC threshold was obtained, the less hearing problems would be faced. PMID:24381615

Efficient delivery of RNA interference oligonucleotides to polarized airway epithelia in vitro

PubMed Central

Ramachandran, Shyam; Krishnamurthy, Sateesh; Jacobi, Ashley M.; Wohlford-Lenane, Christine; Behlke, Mark A.; Davidson, Beverly L.

2013-01-01

Polarized and pseudostratified primary airway epithelia present barriers that significantly reduce their transfection efficiency and the efficacy of RNA interference oligonucleotides. This creates an impediment in studies of the airway epithelium, diminishing the utility of loss-of-function as a research tool. Here we outline methods to introduce RNAi oligonucleotides into primary human and porcine airway epithelia grown at an air-liquid interface and difficult-to-transfect transformed epithelial cell lines grown on plastic. At the time of plating, we reverse transfect small-interfering RNA (siRNA), Dicer-substrate siRNA, or microRNA oligonucleotides into cells by use of lipid or peptide transfection reagents. Using this approach we achieve significant knockdown in vitro of hypoxanthine-guanine phosphoribosyltransferase, IL-8, and CFTR expression at the mRNA and protein levels in 1–3 days. We also attain significant reduction of secreted IL-8 in polarized primary pig airway epithelia 3 days posttransfection and inhibition of CFTR-mediated Cl− conductance in polarized air-liquid interface cultures of human airway epithelia 2 wk posttransfection. These results highlight an efficient means to deliver RNA interference reagents to airway epithelial cells and achieve significant knockdown of target gene expression and function. The ability to reliably conduct loss-of-function assays in polarized primary airway epithelia offers benefits to research in studies of epithelial cell homeostasis, candidate gene function, gene-based therapeutics, microRNA biology, and targeting the replication of respiratory viruses. PMID:23624792

Advanced technique for long term culture of epithelia in a continuous luminal-basal medium gradient.

PubMed

Schumacher, Karl; Strehl, Raimund; de, Vries Uwe; Minuth, Will W

2002-02-01

The majority of epithelia in our organism perform barrier functions on being exposed to different fluids at the luminal and basal sides. To simulate this natural situation under in vitro conditions for biomaterial testing and tissue engineering the epithelia have to withstand mechanical and fluid stress over a prolonged period of time. Leakage, edge damage and pressure differences in the culture system have to be avoided so that the epithelial barrier function is maintained. Besides, the environmental influences on important cell biological features such as, sealing or transport functions, have to remain upregulated and a loss of characteristics by dedifferentiation is prevented. Our aim is to expose embryonic renal collecting duct (CD) epithelia as model tissue for 14 days to fluid gradients and to monitor the development of tissue-specific features. For these experiments, cultured embryonic epithelia are placed in tissue carriers and in gradient containers, where different media are superfused at the luminal and basal sides. Epithelia growing on the tissue carriers act as a physiological barrier during the whole culture period. To avoid mechanical damage of the tissue and to suppress fluid pressure differences between the luminal and basal compartments improved transport of the medium and an elimination of unilaterally accumulated gas bubbles in the gradient container compartments by newly developed gas expander modules is introduced. By the application of these tools the yield of embryonic renal collecting duct epithelia with intact barrier function on a fragile natural support material could be increased significantly as compared to earlier experiments. Epithelia treated with a luminal NaCl load ranging from 3 to 24 mmol l were analyzed by immunohistochemical methods to determine the degree of differentiation. The tissue showed an upregulation of individual CD cell features as compared to embryonic epithelia in the neonatal kidney.

Mucin gene expression in human male urogenital tract epithelia

PubMed Central

Russo, Cindy Leigh; Spurr-Michaud, Sandra; Tisdale, Ann; Pudney, Jeffrey; Anderson, Deborah; Gipson, Ilene K.

2010-01-01

BACKGROUND Mucins are large, hydrophilic glycoproteins that protect wet-surfaced epithelia from pathogen invasion as well as provide lubrication. At least 17 mucin genes have been cloned to date. This study sought to determine the mucin gene expression profile of the human male urogenital tract epithelia, to determine if mucins are present in seminal fluid, and to assess the effect of androgens on mucin expression. METHODS AND RESULTS Testis, epididymis, vas deferens, seminal vesicle, prostate, bladder, urethra and foreskin were assessed for mucin expression by RT-PCR and immunohistochemistry. Epithelia of the vas deferens, prostate and urethra expressed the greatest number of mucins, each expressing 5–8 mucins. Messenger RNA of MUC1 and MUC20, both membrane-associated mucins, were detected in most tissues analyzed. Conversely, MUC6 was predominantly detected in seminal vesicle. MUC1, MUC5B and MUC6 were detected in seminal fluid samples by immunoblot analysis. Androgens had no effect on mucin expression by cultured human prostatic epithelial cells. CONCLUSIONS Each region of urogenital tract epithelium expressed a unique mucin gene repertoire. Secretory mucins are present in seminal fluid, and androgens do not appear to regulate mucin gene expression. PMID:16997931

Manipulation of Cell Physiology Enables Gene Silencing in Well-differentiated Airway Epithelia

PubMed Central

Krishnamurthy, Sateesh; Behlke, Mark A; Ramachandran, Shyam; Salem, Aliasger K; McCray Jr, Paul B; Davidson, Beverly L

2012-01-01

The application of RNA interference-based gene silencing to the airway surface epithelium holds great promise to manipulate host and pathogen gene expression for therapeutic purposes. However, well-differentiated airway epithelia display significant barriers to double-stranded small-interfering RNA (siRNA) delivery despite testing varied classes of nonviral reagents. In well-differentiated primary pig airway epithelia (PAE) or human airway epithelia (HAE) grown at the air–liquid interface (ALI), the delivery of a Dicer-substrate small-interfering RNA (DsiRNA) duplex against hypoxanthine–guanine phosphoribosyltransferase (HPRT) with several nonviral reagents showed minimal uptake and no knockdown of the target. In contrast, poorly differentiated cells (2–5-day post-seeding) exhibited significant oligonucleotide internalization and target knockdown. This finding suggested that during differentiation, the barrier properties of the epithelium are modified to an extent that impedes oligonucleotide uptake. We used two methods to overcome this inefficiency. First, we tested the impact of epidermal growth factor (EGF), a known enhancer of macropinocytosis. Treatment of the cells with EGF improved oligonucleotide uptake resulting in significant but modest levels of target knockdown. Secondly, we used the connectivity map (Cmap) database to correlate gene expression changes during small molecule treatments on various cells types with genes that change upon mucociliary differentiation. Several different drug classes were identified from this correlative assessment. Well-differentiated epithelia treated with DsiRNAs and LY294002, a PI3K inhibitor, significantly improved gene silencing and concomitantly reduced target protein levels. These novel findings reveal that well-differentiated airway epithelia, normally resistant to siRNA delivery, can be pretreated with small molecules to improve uptake of synthetic oligonucleotide and RNA interference (RNAi) responses. PMID

An ErbB2-Muc4 complex in rat ocular surface epithelia.

PubMed

Swan, Jeremy S; Arango, Maria E; Carothers Carraway, Coralie A; Carraway, Kermit L

2002-05-01

To show the presence and localization of type 1 growth factor receptors (ErbB2, ErbB3 and ErbB4) in rat corneal and conjunctival epithelia and investigate the association of ErbB2 with its intramembrane ligand Muc4. Methacarn-fixed, paraffin-embedded sections of corneas and eyelids from female adult rats were immunocytochemically stained using antibodies against the ErbB receptors and Muc4. Sequential immunoprecipitation and immunoblot analyses were performed on epithelial lysates to investigate the presence of a complex of Muc4 and ErbB2 in corneal and conjunctival epithelia. Immunocytochemical staining demonstrated the presence of ErbB2, ErbB3 and ErbB4 growth factor receptors throughout the rat corneal and conjunctival epithelia. Co-immunoprecipitation of the epithelial lysates demonstrated that Muc4 and ErbB2 are present as a complex. The three type 1 growth factor receptors (ErbB2, ErbB3 and ErbB4) are present in the rat corneal and conjunctival epithelia, and ErbB2 is at least partly associated with Muc4. This demonstration of the presence and localization of these three type 1 growth factor receptors may help in understanding how these receptors contribute to ocular epithelial behavior and functions.

Ear discharge

MedlinePlus

... swabs or other small objects into the ear Middle ear infection Other causes of ear discharge include: Eczema ... tube surgery - what to ask your doctor Images Ear anatomy Eardrum repair - series References Bauer CA, Jenkins HA. Otologic symptoms and syndromes. In: Flint PW, Haughey BH, Lund V, et ...

Ear wax

MedlinePlus

See your provider if your ears are blocked with wax and you are unable to remove the wax. Also call if you have an ear wax blockage and you develop new symptoms, such as: Drainage from the ear Ear pain Fever Hearing loss that continues after you clean the wax

Regeneration and replacement in the vertebrate inner ear.

PubMed

Matsui, Jonathan I; Parker, Mark A; Ryals, Brenda M; Cotanche, Douglas A

2005-10-01

Deafness affects more than 40 million people in the UK and the USA, and many more world-wide. The primary cause of hearing loss is damage to or death of the sensory receptor cells in the inner ear, the hair cells. Birds can readily regenerate their cochlear hair cells but the mammalian cochlea has shown no ability to regenerate after damage. Current research efforts are focusing on gene manipulation, gene therapy and stem cell transplantation for repairing or replacing damaged mammalian cochlear hair cells, which could lead to therapies for treating deafness in humans.

Cytoskeleton in motion: the dynamics of keratin intermediate filaments in epithelia.

PubMed

Windoffer, Reinhard; Beil, Michael; Magin, Thomas M; Leube, Rudolf E

2011-09-05

Epithelia are exposed to multiple forms of stress. Keratin intermediate filaments are abundant in epithelia and form cytoskeletal networks that contribute to cell type-specific functions, such as adhesion, migration, and metabolism. A perpetual keratin filament turnover cycle supports these functions. This multistep process keeps the cytoskeleton in motion, facilitating rapid and protein biosynthesis-independent network remodeling while maintaining an intact network. The current challenge is to unravel the molecular mechanisms underlying the regulation of the keratin cycle in relation to actin and microtubule networks and in the context of epithelial tissue function.

Cytoskeleton in motion: the dynamics of keratin intermediate filaments in epithelia

PubMed Central

Windoffer, Reinhard; Beil, Michael; Magin, Thomas M.

2011-01-01

Epithelia are exposed to multiple forms of stress. Keratin intermediate filaments are abundant in epithelia and form cytoskeletal networks that contribute to cell type–specific functions, such as adhesion, migration, and metabolism. A perpetual keratin filament turnover cycle supports these functions. This multistep process keeps the cytoskeleton in motion, facilitating rapid and protein biosynthesis–independent network remodeling while maintaining an intact network. The current challenge is to unravel the molecular mechanisms underlying the regulation of the keratin cycle in relation to actin and microtubule networks and in the context of epithelial tissue function. PMID:21893596

Tissue-specific roles of Tbx1 in the development of the outer, middle and inner ear, defective in 22q11DS patients

PubMed Central

Arnold, Jelena S.; Braunstein, Evan M.; Ohyama, Takahiro; Groves, Andrew K.; Adams, Joe C.; Brown, M. Christian; Morrow, Bernice E.

2007-01-01

Most 22q11.2 deletion syndrome (22q11DS) patients have middle and outer ear anomalies, whereas some have inner ear malformations. Tbx1, a gene hemizygously deleted in 22q11DS patients and required for ear development, is expressed in multiple tissues during embryogenesis. To determine the role of Tbx1 in the first pharyngeal pouch (PPI) in forming outer and middle ears, we tissue-specifically inactivated the gene using Foxg1-Cre. In the conditional mutants, PPI failed to outgrow, preventing the middle ear bone condensations from forming. Tbx1 was also inactivated in the otic vesicle (OV), resulting in the failure of inner ear sensory organ formation, and in duplication of the cochleovestibular ganglion (CVG). Consistent with the anatomical defects, the sensory genes, Otx1 and Bmp4 were downregulated, whereas the CVG genes, Fgf3 and NeuroD, were upregulated. To delineate Tbx1 cell-autonomous roles, a more selective ablation, exclusively in the OV, was performed using Pax2-Cre. In contrast to the Foxg1-Cre mutants, Pax2-Cre conditional mutant mice survived to adulthood and had normal outer and middle ears but had the same inner ear defects as the Tbx1 null mice, with the same gene expression changes. These results demonstrate that Tbx1 has non-cell autonomous roles in PPI in the formation of outer and middle ears and cell-autonomous roles in the OV. Periotic mesenchymal markers, Prx2 and Brn4 were normal in both conditional mutants, whereas they were diminished in Tbx1−/− embryos. Thus, Tbx1 in the surrounding mesenchyme in both sets of conditional mutants cannot suppress the defects in the OV that occur in the null mutants. PMID:16600992

Ear Pieces

ERIC Educational Resources Information Center

DiJulio, Betsy

2011-01-01

In this article, the author describes an art project wherein students make fanciful connections between art and medicine. This project challenges students to interpret "ear idioms" (e.g. "blow it out your ear," "in one ear and out the other") by relying almost entirely on realistic ear drawings, the placement of them, marks, and values. In that…

Functional morphology of the inner ear and underwater audiograms of Proteus anguinus (Amphibia, Urodela).

PubMed

Bulog, B; Schlegel, P

2000-01-01

Octavolateral sensory organs (auditory and lateral line organs) of cave salamander Proteus anguinus are highly differentiated. In the saccular macula of the inner ear the complex pattern of hair cell orientation and the large otoconial mass enable particle displacement direction detection. Additionally, the same organ, through air cavities within the body, enables detection of underwater sound pressure changes thus acting as a hearing organ. The cavities in the lungs and mouth of Proteus are a resonators that transmit underwater sound pressure to the inner ear. Behaviourally determined audiograms indicate hearing sensitivity of 60 dB (rel. 1 microPa) at frequencies between 1 and 10 kHz. The hearing frequency range was between 10 Hz and 10 kHz. The hearing sensitivities of depigmented Proteus and black Proteus were compared. The highest sensitivities of the depigmented animals (N=4) were at frequencies 1.3-1.7 kHz and it was 2 kHz in black animals (N=1). Excellent underwater hearing abilities of Proteus are sensory adaptations to cave habitat.

Constitutive and inducible expression of SKALP/elafin provides anti-elastase defense in human epithelia.

PubMed Central

Pfundt, R; van Ruissen, F; van Vlijmen-Willems, I M; Alkemade, H A; Zeeuwen, P L; Jap, P H; Dijkman, H; Fransen, J; Croes, H; van Erp, P E; Schalkwijk, J

1996-01-01

Skin-derived antileukoproteinase (SKALP), also known as elafin, is a serine proteinase inhibitor first discovered in keratinocytes from hyperproliferative human epidermis. In addition to the proteinase inhibiting domain which is directed against polymorphonuclear leukocyte (PMN) derived enzymes such as elastase and proteinase 3, SKALP contains multiple transglutaminase (TGase) substrate domains which enable crosslinking to extracellular and cell envelope proteins. Here we show that SKALP is constitutively expressed in several epithelia that are continuously subjected to inflammatory stimuli, such as the oral cavity and the vagina where it co-localizes with type 1 TGase. All epithelia from sterile body cavities are negative for SKALP. In general, stratified squamous epithelia are positive, whereas pseudostratified epithelia, simple/glandular epithelia and normal epidermis are negative. SKALP was found in fetal tissues of the oral cavity from 17 wk gestation onwards where it continued to be expressed up to adult life. Remarkably, in fetal epidermis SKALP was found from week 28 onwards, but was downregulated to undetectable levels in neonatal skin within three months, suggesting a role during pregnancy in feto-maternal interactions or in the early maturation phase of the epidermis. Immunoelectron microscopy revealed the presence of SKALP in secretory vesicles including the lamellar granules. In culture models for epidermal keratinocytes we found that expression of the endogenous SKALP gene provided protection against cell detachment caused by purified elastase or activated PMNs. Addition of exogenous recombinant SKALP fully protected the keratinocytes against PMN-dependent detachment whereas superoxide dismutase and catalase were only marginally effective. These findings strongly suggest that the constitutive expression of SKALP in squamous epithelia, and the inducible expression in epidermis participate in the control of epithelial integrity, by inhibiting PMN

Topological defects in epithelia govern cell death and extrusion

NASA Astrophysics Data System (ADS)

Saw, Thuan Beng; Doostmohammadi, Amin; Nier, Vincent; Kocgozlu, Leyla; Thampi, Sumesh; Toyama, Yusuke; Marcq, Philippe; Lim, Chwee Teck; Yeomans, Julia M.; Ladoux, Benoit

2017-04-01

Epithelial tissues (epithelia) remove excess cells through extrusion, preventing the accumulation of unnecessary or pathological cells. The extrusion process can be triggered by apoptotic signalling, oncogenic transformation and overcrowding of cells. Despite the important linkage of cell extrusion to developmental, homeostatic and pathological processes such as cancer metastasis, its underlying mechanism and connections to the intrinsic mechanics of the epithelium are largely unexplored. We approach this problem by modelling the epithelium as an active nematic liquid crystal (that has a long range directional order), and comparing numerical simulations to strain rate and stress measurements within monolayers of MDCK (Madin Darby canine kidney) cells. Here we show that apoptotic cell extrusion is provoked by singularities in cell alignments in the form of comet-shaped topological defects. We find a universal correlation between extrusion sites and positions of nematic defects in the cell orientation field in different epithelium types. The results confirm the active nematic nature of epithelia, and demonstrate that defect-induced isotropic stresses are the primary precursors of mechanotransductive responses in cells, including YAP (Yes-associated protein) transcription factor activity, caspase-3-mediated cell death, and extrusions. Importantly, the defect-driven extrusion mechanism depends on intercellular junctions, because the weakening of cell-cell interactions in an α-catenin knockdown monolayer reduces the defect size and increases both the number of defects and extrusion rates, as is also predicted by our model. We further demonstrate the ability to control extrusion hotspots by geometrically inducing defects through microcontact printing of patterned monolayers. On the basis of these results, we propose a mechanism for apoptotic cell extrusion: spontaneously formed topological defects in epithelia govern cell fate. This will be important in predicting

Connecting the ear to the brain: molecular mechanisms of auditory circuit assembly

PubMed Central

Appler, Jessica M.; Goodrich, Lisa V.

2011-01-01

Our sense of hearing depends on precisely organized circuits that allow us to sense, perceive, and respond to complex sounds in our environment, from music and language to simple warning signals. Auditory processing begins in the cochlea of the inner ear, where sounds are detected by sensory hair cells and then transmitted to the central nervous system by spiral ganglion neurons, which faithfully preserve the frequency, intensity, and timing of each stimulus. During the assembly of auditory circuits, spiral ganglion neurons establish precise connections that link hair cells in the cochlea to target neurons in the auditory brainstem, develop specific firing properties, and elaborate unusual synapses both in the periphery and in the CNS. Understanding how spiral ganglion neurons acquire these unique properties is a key goal in auditory neuroscience, as these neurons represent the sole input of auditory information to the brain. In addition, the best currently available treatment for many forms of deafness is the cochlear implant, which compensates for lost hair cell function by directly stimulating the auditory nerve. Historically, studies of the auditory system have lagged behind other sensory systems due to the small size and inaccessibility of the inner ear. With the advent of new molecular genetic tools, this gap is narrowing. Here, we summarize recent insights into the cellular and molecular cues that guide the development of spiral ganglion neurons, from their origin in the proneurosensory domain of the otic vesicle to the formation of specialized synapses that ensure rapid and reliable transmission of sound information from the ear to the brain. PMID:21232575

Ear wax

PubMed Central

2008-01-01

Introduction Ear wax only becomes a problem if it causes a hearing impairment or other ear-related symptoms. Ear wax is more likely to accumulate and cause a hearing impairment when normal extrusion is prevented — for example, by the use of hearing aids, or by the use of cotton buds to clean the ears. Ear wax can visually obscure the ear drum, and may need to be removed for diagnostic purposes. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of methods to remove ear wax? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2007 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found nine systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: ear syringing; manual removal (other than ear syringing); and wax softeners (alone or prior to syringing). PMID:19450340

Expression of the mouse Macf2 gene during inner ear development.

PubMed

Leonova, Elena V; Lomax, Margaret I

2002-09-30

Plakins, a family of linker proteins that connect cytoskeletal elements to cellular junctions and the extracellular matrix, are primarily responsible for the mechanical properties of cells and tissues. They include desmoplakin, envoplakin, plectin, dystonin/BPAG1, and Kakapo. Mutations in plakins cause several skin, muscular and neurological disorders. Macrophins are a recently discovered subfamily of plakins with binding domains for actin, intermediate filaments and microtubules. Characteristic features of macrophins include variable actin binding domains, a central rod domain containing both plectin and spectrin repeats, and a C-terminus containing EF hands and GAS2/GAR22 domain. We have examined expression of mouse Macf2, encoding macrophin-2, in adult tissues and in the developing, neonatal, and mature inner ear by in situ hybridization. Northern blot analysis identified three large tissue-specific Macf2 transcripts: a 16-kb mRNA in skeletal muscle and heart, a 15-kb mRNA in brain, and a 9-kb mRNA in RNA from ovary plus uterus. In situ hybridization of the developing mouse inner ear indicated that Macf2 is expressed in the otocyst at day 12.5, in the sensory epithelium by embryonic day 16.5, and in both inner and outer hair cells by day 16.5. Macf2 is expressed in the bodies of both sensory and motor neurons in the central and peripheral nervous system, including the auditory pathway. The Macf2 protein could be involved in the regulation of cytoskeletal connections to cellular junctions and play an important structural role in organs, such as the inner ear, that are subjected to strong mechanical forces. Copyright 2002 Elsevier Science B.V.

Ear Disorders

MedlinePlus

... most common illness in infants and young children. Tinnitus, a roaring in your ears, can be the ... problems in your inner ear; its symptoms include tinnitus and dizziness. Ear barotrauma is an injury to ...

Mucin gene expression is not regulated by estrogen and/or progesterone in the ocular surface epithelia of mice.

PubMed

Lange, Christine; Fernandez, Jolene; Shim, David; Spurr-Michaud, Sandra; Tisdale, Ann; Gipson, Ilene K

2003-07-01

Dry eye syndrome is prevalent in post-menopausal women, and post-menopausal women secrete less mucus in their reproductive tracts. Using a mouse model, the purpose of this study was to determine if estrogen and/or progesterone regulates Muc4 and Muc5AC gene expression in the ocular surface epithelia, as the hormones do in reproductive tract epithelia. Adult C57BL/6 mice were ovariectomized, and 19 days later, pellets containing estrogen, progesterone, or a combination were inserted subcutaneously. Ocular surface and reproductive tract tissues were harvested following seven days of hormone treatment. A control group consisted of ovariectomized mice that received no hormone treatment. Real-time reverse transcription-polymerase chain reaction was used to determine the tissue expression levels of mucin mRNA of each treatment group relative to the control. Muc4 mRNA expression levels were determined for the reproductive tract, and both Muc4 and Muc5AC expression levels were determined for the ocular surface epithelia. Muc4 and Muc5AC gene expression in ocular surface and Muc4 in reproductive tract epithelia was demonstrated by In Situ hybridization, and Muc4 and Muc5AC protein was demonstrated in the epithelia of animals in the experimental groups. The mRNA expression levels of Muc4 and Muc5AC and the immunofluorescence localization pattern in the ocular surface epithelia were not significantly different in any hormone treatment group when compared to the control ovariectomized group. By comparison, mice that were administered estrogen had a significant increase of Muc4 mRNA in the reproductive tract epithelia, progesterone given in combination with estrogen antagonized the upregulatory effects of estrogen in the reproductive tract, and the amount of Muc4 mRNA in the reproductive tract of progesterone-treated animals was not different from ovariectomized controls. Immunofluorescence localization of Muc4 in the reproductive tract epithelia of the experimental groups

Macrophage migration inhibitory factor acts as a neurotrophin in the developing inner ear.

PubMed

Bank, Lisa M; Bianchi, Lynne M; Ebisu, Fumi; Lerman-Sinkoff, Dov; Smiley, Elizabeth C; Shen, Yu-chi; Ramamurthy, Poornapriya; Thompson, Deborah L; Roth, Therese M; Beck, Christine R; Flynn, Matthew; Teller, Ryan S; Feng, Luming; Llewellyn, G Nicholas; Holmes, Brandon; Sharples, Cyrrene; Coutinho-Budd, Jaeda; Linn, Stephanie A; Chervenak, Andrew P; Dolan, David F; Benson, Jennifer; Kanicki, Ariane; Martin, Catherine A; Altschuler, Richard; Koch, Alisa E; Koch, Alicia E; Jewett, Ethan M; Germiller, John A; Barald, Kate F

2012-12-01

This study is the first to demonstrate that macrophage migration inhibitory factor (MIF), an immune system 'inflammatory' cytokine that is released by the developing otocyst, plays a role in regulating early innervation of the mouse and chick inner ear. We demonstrate that MIF is a major bioactive component of the previously uncharacterized otocyst-derived factor, which directs initial neurite outgrowth from the statoacoustic ganglion (SAG) to the developing inner ear. Recombinant MIF acts as a neurotrophin in promoting both SAG directional neurite outgrowth and neuronal survival and is expressed in both the developing and mature inner ear of chick and mouse. A MIF receptor, CD74, is found on both embryonic SAG neurons and adult mouse spiral ganglion neurons. Mif knockout mice are hearing impaired and demonstrate altered innervation to the organ of Corti, as well as fewer sensory hair cells. Furthermore, mouse embryonic stem cells become neuron-like when exposed to picomolar levels of MIF, suggesting the general importance of this cytokine in neural development.

Swimmer's Ear

MedlinePlus

... Eardrum Taking Care of Your Ears Can Loud Music Hurt My Ears? Your Ears What's Earwax? How Do Pain Relievers Work? View more About Us Contact Us Partners Editorial Policy Permissions Guidelines Privacy Policy & Terms of Use Notice ...

Chloride and potassium channels in cystic fibrosis airway epithelia

NASA Astrophysics Data System (ADS)

Welsh, Michael J.; Liedtke, Carole M.

1986-07-01

Cystic fibrosis, the most common lethal genetic disease in Caucasians, is characterized by a decreased permeability in sweat gland duct and airway epithelia. In sweat duct epithelium, a decreased Cl- permeability accounts for the abnormally increased salt content of sweat1. In airway epithelia a decreased Cl- permeability, and possibly increased sodium absorption, may account for the abnormal respiratory tract fluid2,3. The Cl- impermeability has been localized to the apical membrane of cystic fibrosis airway epithelial cells4. The finding that hormonally regulated Cl- channels make the apical membrane Cl- permeable in normal airway epithelial cells5 suggested abnormal Cl- channel function in cystic fibrosis. Here we report that excised, cell-free patches of membrane from cystic fibrosis epithelial cells contain Cl- channels that have the same conductive properties as Cl- channels from normal cells. However, Cl- channels from cystic fibrosis cells did not open when they were attached to the cell. These findings suggest defective regulation of Cl- channels in cystic fibrosis epithelia; to begin to address this issue, we performed two studies. First, we found that isoprenaline, which stimulates Cl- secretion, increases cellular levels of cyclic AMP in a similar manner in cystic fibrosis and non-cystic fibrosis epithelial cells. Second, we show that adrenergic agonists open calcium-activated potassium channels, indirectly suggesting that calcium-dependent stimulus-response coupling is intact in cystic fibrosis. These data suggest defective regulation of Cl- channels at a site distal to cAMP accumulation.

Autonomous assembly of epithelial structures by subrenal implantation of dissociated embryonic inner-ear cells.

PubMed

Wang, Li; Zhang, Kaiqing; Zhu, Helen He; Gao, Wei-Qiang

2015-05-27

Microenvironment and cell-cell interactions play an important role during embryogenesis and are required for the stemness and differentiation of stem cells. The inner-ear sensory epithelium, containing hair cells and supporting cells, is derived from the stem cells within the otic vesicle at early embryonic stages. However, whether or not such microenvironment or cell-cell interactions within the embryonic otic tissue have the capacity to regulate the proliferation and differentiation of stem cells and to autonomously reassemble the cells into epithelial structures is unknown. Here, we report that on enzymatic digestion and dissociation to harvest all the single cells from 13.5-day-old rat embryonic (E13.5) inner-ear tissue as well as on implantation of these cells under renal capsules; the dissociated cells are able to reassemble themselves to form epithelial structures as early as 7 days after implantation. By 25 days after implantation, more mature epithelial structures are formed. Immunostaining with cell-type-specific markers reveals that hair cells and supporting cells are not only formed, but are also well aligned with the hair cells located in the apical layer surrounded by the supporting cells. These findings suggest that microenvironment and cell-cell interactions within the embryonic inner-ear tissue have the autonomous signals to induce the formation of sensory epithelial structures. This method may also provide a useful system to study the potential of stem cells to differentiate into hair cells in vivo.

Ear Scaffold Reconstruction Using Ultrasonic Aspirator for Cauliflower Ear.

PubMed

Hao, Scarlett; Angster, Kristen; Hubbard, Fleesie; Greywoode, Jewel; Vakharia, Kalpesh T

2018-04-01

Untreated auricular hematomas from ear trauma can result in an ear deformation known as cauliflower ear, secondary to fibrosis and new cartilage overgrowth. Cauliflower ear reconstruction has traditionally utilized tools such as a drill or a scalpel in order to improve auricular cosmesis. We present a case report utilizing an ultrasonic aspirator to recontour the fibrosed cartilage of a cauliflower ear. The ultrasonic aspirator has advantages over traditional tools in its ability to provide finely controlled bone removal without damage to surrounding soft tissue. The patient in this case report underwent multistage reconstruction using the ultrasonic aspirator with excellent cosmetic result and patient satisfaction.

Ear Problems

MedlinePlus

... may have OTITIS MEDIA, an infection of the middle ear. Self CareSee your doctor. Many ear infections will ... half-alcohol, half-white vinegar solution in the ear before and after swimming or ... JOINT (TMJ) SYNDROME, a disorder that affects the jaw joint, may ...

Tympanal mechanics and neural responses in the ears of a noctuid moth

NASA Astrophysics Data System (ADS)

Ter Hofstede, Hannah M.; Goerlitz, Holger R.; Montealegre-Z, Fernando; Robert, Daniel; Holderied, Marc W.

2011-12-01

Ears evolved in many groups of moths to detect the echolocation calls of predatory bats. Although the neurophysiology of bat detection has been intensively studied in moths for decades, the relationship between sound-induced movement of the noctuid tympanic membrane and action potentials in the auditory sensory cells (A1 and A2) has received little attention. Using laser Doppler vibrometry, we measured the velocity and displacement of the tympanum in response to pure tone pulses for moths that were intact or prepared for neural recording. When recording from the auditory nerve, the displacement of the tympanum at the neural threshold remained constant across frequencies, whereas velocity varied with frequency. This suggests that the key biophysical parameter for triggering action potentials in the sensory cells of noctuid moths is tympanum displacement, not velocity. The validity of studies on the neurophysiology of moth hearing rests on the assumption that the dissection and recording procedures do not affect the biomechanics of the ear. There were no consistent differences in tympanal velocity or displacement when moths were intact or prepared for neural recordings for sound levels close to neural threshold, indicating that this and other neurophysiological studies provide good estimates of what intact moths hear at threshold.

Ear Tubes

MedlinePlus

... of the ear drum or eustachian tube, Down Syndrome, cleft palate, and barotrauma (injury to the middle ear caused by a reduction of air pressure, ... specialist) may be warranted if you or your child has experienced repeated ... fluid in the middle ear, barotrauma, or have an anatomic abnormality that ...

Calcium oxalate stone formation in the inner ear as a result of an Slc26a4 mutation.

PubMed

Dror, Amiel A; Politi, Yael; Shahin, Hashem; Lenz, Danielle R; Dossena, Silvia; Nofziger, Charity; Fuchs, Helmut; Hrabé de Angelis, Martin; Paulmichl, Markus; Weiner, Steve; Avraham, Karen B

2010-07-09

Calcium oxalate stone formation occurs under pathological conditions and accounts for more than 80% of all types of kidney stones. In the current study, we show for the first time that calcium oxalate stones are formed in the mouse inner ear of a genetic model for hearing loss and vestibular dysfunction in humans. The vestibular system within the inner ear is dependent on extracellular tiny calcium carbonate minerals for proper function. Thousands of these biominerals, known as otoconia, are associated with the utricle and saccule sensory maculae and are vital for mechanical stimulation of the sensory hair cells. We show that a missense mutation within the Slc26a4 gene abolishes the transport activity of its encoded protein, pendrin. As a consequence, dramatic changes in mineral composition, size, and shape occur within the utricle and saccule in a differential manner. Although abnormal giant carbonate minerals reside in the utricle at all ages, in the saccule, a gradual change in mineral composition leads to a formation of calcium oxalate in adult mice. By combining imaging and spectroscopy tools, we determined the profile of mineral composition and morphology at different time points. We propose a novel mechanism for the accumulation and aggregation of oxalate crystals in the inner ear.

Phenylbutyrate counteracts Shigella mediated downregulation of cathelicidin in rabbit lung and intestinal epithelia: a potential therapeutic strategy.

PubMed

Sarker, Protim; Ahmed, Sultan; Tiash, Snigdha; Rekha, Rokeya Sultana; Stromberg, Roger; Andersson, Jan; Bergman, Peter; Gudmundsson, Gudmundur H; Agerberth, Birgitta; Raqib, Rubhana

2011-01-01

Cathelicidins and defensins are endogenous antimicrobial peptides (AMPs) that are downregulated in the mucosal epithelia of the large intestine in shigellosis. Oral treatment of Shigella infected rabbits with sodium butyrate (NaB) reduces clinical severity and counteracts the downregulation of cathelicidin (CAP-18) in the large intestinal epithelia. To develop novel regimen for treating infectious diseases by inducing innate immunity, we selected sodium 4-phenylbutyrate (PB), a registered drug for a metabolic disorder as a potential therapeutic candidate in a rabbit model of shigellosis. Since acute respiratory infections often cause secondary complications during shigellosis, the systemic effect of PB and NaB on CAP-18 expression in respiratory epithelia was also evaluated. The readouts were clinical outcomes, CAP-18 expression in mucosa of colon, rectum, lung and trachea (immunohistochemistry and real-time PCR) and release of the CAP-18 peptide/protein in stool (Western blot). Significant downregulation of CAP-18 expression in the epithelia of rectum and colon, the site of Shigella infection was confirmed. Interestingly, reduced expression of CAP-18 was also noticed in the epithelia of lung and trachea, indicating a systemic effect of the infection. This suggests a causative link to acute respiratory infections during shigellosis. Oral treatment with PB resulted in reduced clinical illness and upregulation of CAP-18 in the epithelium of rectum. Both PB and NaB counteracted the downregulation of CAP-18 in lung epithelium. The drug effect is suggested to be systemic as intravenous administration of NaB could also upregulate CAP-18 in the epithelia of lung, rectum and colon. Our results suggest that PB has treatment potential in human shigellosis. Enhancement of CAP-18 in the mucosal epithelia of the respiratory tract by PB or NaB is a novel discovery. This could mediate protection from secondary respiratory infections that frequently are the lethal causes in

Olfactory imprinting is correlated with changes in gene expression in the olfactory epithelia of the zebrafish.

PubMed

Harden, Maegan V; Newton, Lucy A; Lloyd, Russell C; Whitlock, Kathleen E

2006-11-01

Odors experienced as juveniles can have significant effects on the behavior of mature organisms. A dramatic example of this occurs in salmon, where the odors experienced by developing fish determine the river to which they return as adults. Further examples of olfactory memories are found in many animals including vertebrates and invertebrates. Yet, the cellular and molecular bases underlying the formation of olfactory memory are poorly understood. We have devised a series of experiments to determine whether zebrafish can form olfactory memories much like those observed in salmonids. Here we show for the first time that zebrafish form and retain olfactory memories of an artificial odorant, phenylethyl alcohol (PEA), experienced as juveniles. Furthermore, we demonstrate that exposure to PEA results in changes in gene expression within the olfactory sensory system. These changes are evident by in situ hybridization in the olfactory epithelium of the developing zebrafish. Strikingly, our analysis by in situ hybridization demonstrates that the transcription factor, otx2, is up regulated in the olfactory sensory epithelia in response to PEA. This increase is evident at 2-3 days postfertilization and is maintained in the adult animals. We propose that the changes in otx2 gene expression are manifest as an increase in the number of neuronal precursors in the cells olfactory epithelium of the odor-exposed fish. Thus, our results reveal a role for the environment in controlling gene expression in the developing peripheral nervous system. Copyright 2006 Wiley Periodicals, Inc.

Microbiomes of the normal middle ear and ears with chronic otitis media.

PubMed

Minami, Shujiro B; Mutai, Hideki; Suzuki, Tomoko; Horii, Arata; Oishi, Naoki; Wasano, Koichiro; Katsura, Motoyasu; Tanaka, Fujinobu; Takiguchi, Tetsuya; Fujii, Masato; Kaga, Kimitaka

2017-10-01

The aim of this study was to profile and compare the middle ear microbiomes of human subjects with and without chronic otitis media. Prospective multicenter cohort study. All consecutive patients undergoing tympanoplasty surgery for chronic otitis media or ear surgery for conditions other than otitis media were recruited. Sterile swab samples were collected from the middle ear mucosa during surgery. The variable region 4 of the 16S rRNA gene in each sample were amplified using region-specific primers adapted for the Illumina MiSeq sequencer (Illumina, CA, USA)). The sequences were subjected to local blast and classified using Metagenome@KIN (World Fusion, Tokyo, Japan). In total, 155 participants were recruited from seven medical centers. Of these, 88 and 67 had chronic otitis media and normal middle ears, respectively. The most abundant bacterial phyla on the mucosal surfaces of the normal middle ears were Proteobacteria, followed by Actinobacteria, Firmicutes, and Bacteroidetes. The children and adults with normal middle ears differed significantly in terms of middle ear microbiomes. Subjects with chronic otitis media without active inflammation (dry ear) had similar middle ear microbiomes as the normal middle ears group. Subjects with chronic otitis media with active inflammation (wet ear) had a lower prevalence of Proteobacteria and a higher prevalence of Firmicutes than the normal middle ears. The human middle ear is inhabited by more diverse microbial communities than was previously thought. Alteration of the middle ear microbiome may contribute to the pathogenesis of chronic otitis media with active inflammation. 2b. Laryngoscope, 127:E371-E377, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Ear asymmetries in middle-ear, cochlear, and brainstem responses in human infants

PubMed Central

Keefe, Douglas H.; Gorga, Michael P.; Jesteadt, Walt; Smith, Lynette M.

2008-01-01

In 2004, Sininger and Cone-Wesson examined asymmetries in the signal-to-noise ratio (SNR) of otoacoustic emissions (OAE) in infants, reporting that distortion-product (DP)OAE SNR was larger in the left ear, whereas transient-evoked (TE)OAE SNR was larger in the right. They proposed that cochlear and brainstem asymmetries facilitate development of brain-hemispheric specialization for sound processing. Similarly, in 2006 Sininger and Cone-Wesson described ear asymmetries mainly favoring the right ear in infant auditory brainstem responses (ABRs). The present study analyzed 2640 infant responses to further explore these effects. Ear differences in OAE SNR, signal, and noise were evaluated separately and across frequencies (1.5, 2, 3, and 4 kHz), and ABR asymmetries were compared with cochlear asymmetries. Analyses of ear-canal reflectance and admittance showed that asymmetries in middle-ear functioning did not explain cochlear and brainstem asymmetries. Current results are consistent with earlier studies showing right-ear dominance for TEOAE and ABR. Noise levels were higher in the right ear for OAEs and ABRs, causing ear asymmetries in SNR to differ from those in signal level. No left-ear dominance for DPOAE signal was observed. These results do not support a theory that ear asymmetries in cochlear processing mimic hemispheric brain specialization for auditory processing. PMID:18345839

[Characterization of stem cells derived from the neonatal auditory sensory epithelium].

PubMed

Diensthuber, M; Heller, S

2010-11-01

In contrast to regenerating hair cell-bearing organs of nonmammalian vertebrates the adult mammalian organ of Corti appears to have lost its ability to maintain stem cells. The result is a lack of regenerative ability and irreversible hearing loss following auditory hair cell death. Unexpectedly, the neonatal auditory sensory epithelium has recently been shown to harbor cells with stem cell features. The origin of these cells within the cochlea's sensory epithelium is unknown. We applied a modified neurosphere assay to identify stem cells within distinct subregions of the neonatal mouse auditory sensory epithelium. Sphere cells were characterized by multiple markers and morphologic techniques. Our data reveal that both the greater and the lesser epithelial ridge contribute to the sphere-forming stem cell population derived from the auditory sensory epithelium. These self-renewing sphere cells express a variety of markers for neural and otic progenitor cells and mature inner ear cell types. Stem cells can be isolated from specific regions of the auditory sensory epithelium. The distinct features of these cells imply a potential application in the development of a cell replacement therapy to regenerate the damaged sensory epithelium.

3D finite element model of the chinchilla ear for characterizing middle ear functions

PubMed Central

Wang, Xuelin; Gan, Rong Z.

2016-01-01

Chinchilla is a commonly used animal model for research of sound transmission through the ear. Experimental measurements of the middle ear transfer function in chinchillas have shown that the middle ear cavity greatly affects the tympanic membrane (TM) and stapes footplate (FP) displacements. However, there is no finite element (FE) model of the chinchilla ear available in the literature to characterize the middle ear functions with the anatomical features of the chinchilla ear. This paper reports a recently completed 3D FE model of the chinchilla ear based on X-ray micro-computed tomography images of a chinchilla bulla. The model consisted of the ear canal, TM, middle ear ossicles and suspensory ligaments, and the middle ear cavity. Two boundary conditions of the middle ear cavity wall were simulated in the model as the rigid structure and the partially flexible surface, and the acoustic-mechanical coupled analysis was conducted with these two conditions to characterize the middle ear function. The model results were compared with experimental measurements reported in the literature including the TM and FP displacements and the middle ear input admittance in chinchilla ear. An application of this model was presented to identify the acoustic role of the middle ear septa - a unique feature of chinchilla middle ear cavity. This study provides the first 3D FE model of the chinchilla ear for characterizing the middle ear functions through the acoustic-mechanical coupled FE analysis. PMID:26785845

Identification of Adeno-Associated Viral Vectors That Target Neonatal and Adult Mammalian Inner Ear Cell Subtypes

PubMed Central

Shu, Yilai; Tao, Yong; Wang, Zhengmin; Tang, Yong; Li, Huawei; Dai, Pu; Gao, Guangping; Chen, Zheng-Yi

2016-01-01

The mammalian inner ear consists of diverse cell types with important functions. Gene mutations in these diverse cell types have been found to underlie different forms of genetic hearing loss. Targeting these mutations for gene therapy development represents a future therapeutic strategy to treat hearing loss. Adeno-associated viral (AAV) vectors have become the vector of choice for gene delivery in animal models in vivo. To identify AAV vectors that target inner ear cell subtypes, we systemically screened 12 AAV vectors with different serotypes (AAV1, 2, 5, 6, 6.2, 7, 8, 9, rh.8, rh.10, rh.39, and rh.43) that carry a reporter gene GFP in neonatal and adult mice by microinjection in vivo. We found that most AAVs infect both neonatal and adult inner ear, with different specificities and expression levels. The inner ear cochlear sensory epithelial region, which includes auditory hair cells and supporting cells, is most frequently targeted for gene delivery. Expression of the transgene is sustained, and neonatal inner ear delivery does not adversely affect hearing. Adult inner ear injection of AAV has a similar infection pattern as the younger inner ear, with the exception that outer hair cell death caused by the injection procedure can lead to hearing loss. In the adult, more so than in the neonatal mice, cell types infected and efficiency of infection are correlated with the site of injection. Most infected cells survive in neonatal and adult inner ears. The study adds to the list of AAV vectors that transduce the mammalian inner ear efficiently, providing the tools that are important to study inner ear gene function and for the development of gene therapy to treat hearing loss. PMID:27342665

Concerted action of two dlx paralogs in sensory placode formation.

PubMed

Solomon, Keely S; Fritz, Andreas

2002-07-01

Sensory placodes are ectodermal thickenings that give rise to elements of the vertebrate cranial sensory nervous system, including the inner ear and nose. Although mutations have been described in humans, mice and zebrafish that perturb ear and nose development, no mutation is known to prevent sensory placode formation. Thus, it has been postulated that a functional redundancy exists in the genetic mechanisms that govern sensory placode development. We describe a zebrafish deletion mutation, b380, which results in a lack of both otic and olfactory placodes. The b380 deletion removes several known genes and expressed sequence tags, including dlx3 and dlx7, two transcription factors that share a homoeobox domain similar in sequence to the Drosophila Distal-less gene. dlx3 and dlx7 are expressed in an overlapping pattern in the regions that produce the otic and olfactory placodes in zebrafish. We present evidence suggesting that it is specifically the removal of these two genes that leads to the otic and olfactory phenotype of b380 mutants. Using morpholinos, antisense oligonucleotides that effectively block translation of target genes, we find that functional reduction of both dlx genes contributes to placode loss. Expression patterns of the otic marker pax2.1, olfactory marker anxV and eya1, a marker of both placodes, in morpholino-injected embryos recapitulate the reduced expression of these genes seen in b380 mutants. We also examine expression of dlx3 and dlx7 in the morpholino-injected embryos and present evidence for existence of auto- and cross-regulatory control of expression among these genes. We demonstrate that dlx3 is necessary and sufficient for proper otic and olfactory placode development. However, our results indicate that dlx3 and dlx7 act in concert and their importance in placode formation is only revealed by inactivating both paralogs.

Requirements for FGF3 and FGF10 during inner ear formation.

PubMed

Alvarez, Yolanda; Alonso, Maria Teresa; Vendrell, Victor; Zelarayan, Laura Cecilia; Chamero, Pablo; Theil, Thomas; Bösl, Michael R; Kato, Shigeaki; Maconochie, Mark; Riethmacher, Dieter; Schimmang, Thomas

2003-12-01

Members of the fibroblast growth factor (FGF) gene family control formation of the body plan and organogenesis in vertebrates. FGF3 is expressed in the developing hindbrain and has been shown to be involved in inner ear development of different vertebrate species, including zebrafish, Xenopus, chick and mouse. In the mouse, insertion of a neomycin resistance gene into the Fgf3 gene via homologous recombination results in severe developmental defects during differentiation of the otic vesicle. We have addressed the precise roles of FGF3 and other FGF family members during formation of the murine inner ear using both loss- and gain-of-function experiments. We generated a new mutant allele lacking the entire FGF3-coding region but surprisingly found no evidence for severe defects either during inner ear development or in the mature sensory organ, suggesting the functional involvement of other FGF family members during its formation. Ectopic expression of FGF10 in the developing hindbrain of transgenic mice leads to the formation of ectopic vesicles, expressing some otic marker genes and thus indicating a role for FGF10 during otic vesicle formation. Expression analysis of FGF10 during mouse embryogenesis reveals a highly dynamic pattern of expression in the developing hindbrain, partially overlapping with FGF3 expression and coinciding with formation of the inner ear. However, FGF10 mutant mice have been reported to display only mild defects during inner ear differentiation. We thus created double mutant mice for FGF3 and FGF10, which form severely reduced otic vesicles, suggesting redundant roles of these FGFs, acting in combination as neural signals for otic vesicle formation.

Phenylbutyrate Counteracts Shigella Mediated Downregulation of Cathelicidin in Rabbit Lung and Intestinal Epithelia: A Potential Therapeutic Strategy

PubMed Central

Sarker, Protim; Ahmed, Sultan; Tiash, Snigdha; Rekha, Rokeya Sultana; Stromberg, Roger; Andersson, Jan; Bergman, Peter; Gudmundsson, Gudmundur H.

2011-01-01

Background Cathelicidins and defensins are endogenous antimicrobial peptides (AMPs) that are downregulated in the mucosal epithelia of the large intestine in shigellosis. Oral treatment of Shigella infected rabbits with sodium butyrate (NaB) reduces clinical severity and counteracts the downregulation of cathelicidin (CAP-18) in the large intestinal epithelia. Aims To develop novel regimen for treating infectious diseases by inducing innate immunity, we selected sodium 4-phenylbutyrate (PB), a registered drug for a metabolic disorder as a potential therapeutic candidate in a rabbit model of shigellosis. Since acute respiratory infections often cause secondary complications during shigellosis, the systemic effect of PB and NaB on CAP-18 expression in respiratory epithelia was also evaluated. Methods The readouts were clinical outcomes, CAP-18 expression in mucosa of colon, rectum, lung and trachea (immunohistochemistry and real-time PCR) and release of the CAP-18 peptide/protein in stool (Western blot). Principal findings Significant downregulation of CAP-18 expression in the epithelia of rectum and colon, the site of Shigella infection was confirmed. Interestingly, reduced expression of CAP-18 was also noticed in the epithelia of lung and trachea, indicating a systemic effect of the infection. This suggests a causative link to acute respiratory infections during shigellosis. Oral treatment with PB resulted in reduced clinical illness and upregulation of CAP-18 in the epithelium of rectum. Both PB and NaB counteracted the downregulation of CAP-18 in lung epithelium. The drug effect is suggested to be systemic as intravenous administration of NaB could also upregulate CAP-18 in the epithelia of lung, rectum and colon. Conclusion Our results suggest that PB has treatment potential in human shigellosis. Enhancement of CAP-18 in the mucosal epithelia of the respiratory tract by PB or NaB is a novel discovery. This could mediate protection from secondary respiratory

Some Remarks on Imaging of the Inner Ear: Options and Limitations.

PubMed

Giesemann, A; Hofmann, E

2015-10-01

The temporal bone has a highly complex anatomical structure, in which the sensory organs of the cochlea and the vestibular system are contained within a small space together with the sound-conducting system of the middle ear. Detailed imaging is thus required in this anatomical area. There are a great many clinical aims for which the highest-possible spatial resolution is required. These include the localization of cerebrospinal fluid fistulas, the detection of malformations of the middle and inner ear and the vestibulocochlear nerve, an aberrant course of the facial nerve and anomalies of the arterial and venous structures, the confirmation of dehiscence of the semicircular canals and finally, the verification of endolymphatic hydrops in cases of Ménière's disease. However, the term 'high resolution' is very time dependent. Two milestones in this respect have been (in 1991) the 3D visualization of the inner ear by means of maximum-intensity projection (MIP) of a T2-weighted constructive interference in steady state (CISS) sequence of a 1.5-tesla magnetic resonance imaging (MRI) scanner (Tanioka et al., Radiology 178:141-144, 1991) and (in 1997) imaging of the vestibulocochlear nerve for the diagnosis of hypoplasia inside the internal auditory canal using the same sequence (Casselman et al., Radiology 202:773-781, 1997).The objective of this article is to highlight the options for, and the challenges of, contemporary imaging with regard to some clinical issues relating to the inner ear.

Swimmer's Ear (For Parents)

MedlinePlus

... scratching the ear canal, vigorous ear cleaning with cotton swabs, or putting foreign objects like bobby pins ... Also, never put objects into kids' ears, including cotton-tipped swabs. How Is Swimmer's Ear Treated? Treatment ...

Water Permeability Adjusts Resorption in Lung Epithelia to Increased Apical Surface Liquid Volumes.

PubMed

Schmidt, Hanna; Michel, Christiane; Braubach, Peter; Fauler, Michael; Neubauer, Daniel; Thompson, Kristin E; Frick, Manfred; Mizaikoff, Boris; Dietl, Paul; Wittekindt, Oliver H

2017-03-01

The apical surface liquid (ASL) layer covers the airways and forms a first line of defense against pathogens. Maintenance of ASL volume by airway epithelia is essential for maintaining lung function. The proteolytic activation of epithelial Na + channels is believed to be the dominating mechanism to cope with increases in ASL volumes. Alternative mechanisms, in particular increases in epithelial osmotic water permeability (P osm ), have so far been regarded as rather less important. However, most studies mainly addressed immediate effects upon apical volume expansion (AVE) and increases in ASL. This study addresses the response of lung epithelia to long-term AVE. NCI-H441 cells and primary human tracheal epithelial cells, both cultivated in air-liquid interface conditions, were used as models for the lung epithelium. AVE was established by adding isotonic solution to the apical surface of differentiated lung epithelia, and time course of ASL volume restoration was assessed by the deuterium oxide dilution method. Concomitant ion transport was investigated in Ussing chambers. We identified a low resorptive state immediately after AVE, which coincided with proteolytic ion transport activation within 10-15 minutes after AVE. The main clearance of excess ASL occurred during a delayed (hours after AVE) high resorptive state, which did not correlate with ion transport activation. Instead, high resorptive state onset coincided with an increase in P osm , which depended on aquaporin up-regulation. In summary, our data demonstrate that, aside from ion transport activation, modulation of P osm is a major mechanism to compensate for long-term AVE in lung epithelia.

Expansion method in secondary total ear reconstruction for undesirable reconstructed ear.

PubMed

Liu, Tun; Hu, Jintian; Zhou, Xu; Zhang, Qingguo

2014-09-01

Ear reconstruction by autologous costal cartilage grafting is the most widely applied technique with fewer complications. However, undesirable ear reconstruction brings more problems to plastic surgeons. Some authors resort to free flap or osseointegration technique with prosthetic ear. In this article, we introduce a secondary total ear reconstruction with expanded skin flap method. From July 2010 to April 2012, 7 cases of undesirable ear reconstruction were repaired by tissue expansion method. Procedures including removal of previous cartilage framework, soft tissue expander insertion, and second stage of cartilage framework insertion were performed to each case regarding their local conditions. The follow-up time ranged from 6 months to 2.5 years. All of the cases recovered well with good 3-dimensional forms, symmetrical auriculocephalic angle, and stable fixation. All these evidence showed that this novel expansion method is safe, stable, and less traumatic for secondary total ear reconstruction. With sufficient expanded skin flap and refabricated cartilage framework, lifelike appearance of reconstructed ear could be acquired without causing additional injury.

Middle Ear Infections and Ear Tube Surgery (For Parents)

MedlinePlus

... Infection? Swimmer's Ear Perforated Eardrum Hearing Impairment Swimmer's Ear (External ... All information on KidsHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, ...

Surgical correction of constricted ear combined with Stahl's ear.

PubMed

Bi, Ye; Lin, Lin; Yang, Qinhua; Pan, Bo; Zhao, Yanyong; He, Leren; Jiang, Haiyue

2015-07-01

Constricted ear combined with Stahl's ear is a rare ear deformity, which is a kind of complex congenital auricular deformity. From 1 January 2007 to 1 January 2014, 19 patients with constricted ear combined with Stahl's ear (Spock ear) were enrolled in this study, most of which were unilaterally deformed. To correct the deformity, a double Z-shaped skin incision was made on the posterior side of the auricle, with the entire layer of cartilage cut parallel to the helix traversing the third crus to form a fan-shaped cartilage flap. The superior crura of the antihelix were shaped by the folding cartilage rim. The cartilage of the abnormal third crus was made part of the new superior crura of antihelix, and the third crus was eliminated. The postoperative aesthetic assessment of the reshaped auricle was graded by both doctors and patients (or their parents). Out of the 19 patients, the number of satisfying cases of the symmetry, helix stretch, elimination of the third crus, the cranioauricular angle, and the substructure of the reshaped ears was 14 (nine excellent and five good), 16 (six excellent and 10 good), 17 (eight excellent and nine good), 15 (five excellent and 10 good), and 13 (two excellent and 11 good), respectively. With a maximum of a 90-month follow-up, no complication was observed. The results of the study suggested that this rare deformity could be corrected by appropriate surgical treatment, with a satisfied postoperative appearance. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Elephant ear

MedlinePlus

... this page: //medlineplus.gov/ency/article/002867.htm Elephant ear poisoning To use the sharing features on this page, please enable JavaScript. Elephant ear plants are indoor or outdoor plants with ...

Localization and proteomic characterization of cholesterol-rich membrane microdomains in the inner ear.

PubMed

Thomas, Paul V; Cheng, Andrew L; Colby, Candice C; Liu, Liqian; Patel, Chintan K; Josephs, Lydia; Duncan, R Keith

2014-05-30

Biological membranes organize and compartmentalize cell signaling into discrete microdomains, a process that often involves stable, cholesterol-rich platforms that facilitate protein-protein interactions. Polarized cells with distinct apical and basolateral cell processes rely on such compartmentalization to maintain proper function. In the cochlea, a variety of highly polarized sensory and non-sensory cells are responsible for the early stages of sound processing in the ear, yet little is known about the mechanisms that traffic and organize signaling complexes within these cells. We sought to determine the prevalence, localization, and protein composition of cholesterol-rich lipid microdomains in the cochlea. Lipid raft components, including the scaffolding protein caveolin and the ganglioside GM1, were found in sensory, neural, and glial cells. Mass spectrometry of detergent-resistant membrane (DRM) fractions revealed over 600 putative raft proteins associated with subcellular localization, trafficking, and metabolism. Among the DRM constituents were several proteins involved in human forms of deafness including those involved in ion homeostasis, such as the potassium channel KCNQ1, the co-transporter SLC12A2, and gap junction proteins GJA1 and GJB6. The presence of caveolin in the cochlea and the abundance of proteins in cholesterol-rich DRM suggest that lipid microdomains play a significant role in cochlear physiology. Although mechanisms underlying cholesterol synthesis, homeostasis, and compartmentalization in the ear are poorly understood, there are several lines of evidence indicating that cholesterol is a key modulator of cochlear function. Depletion of cholesterol in mature sensory cells alters calcium signaling, changes excitability during development, and affects the biomechanical processes in outer hair cells that are responsible for hearing acuity. More recently, we have established that the cholesterol-modulator beta-cyclodextrin is capable of

Utility of HoxB2 enhancer-mediated Cre activity for functional studies in the developing inner ear.

PubMed

Szeto, Irene Y Y; Leung, Keith K H; Sham, Mai Har; Cheah, Kathryn S E

2009-06-01

The rhombomere 4(r4)-restricted expression of the mouse Hoxb2 gene is regulated by a 1.4-kb enhancer-containing fragment. Here, we showthat transgenic mouse lines expressing cre driven by this fragment (B2-r4-Cre), activated the R26R Cre reporter in rhombomere 4 and the second branchial arch, the epithelium of the first branchial arch, apical ectodermal ridge of the limb buds and the tail region. Of particular interest is Cre activity in the developing inner ear. Cre activity was found in the preotic field and otic placode at E8.5 and otocyst at E9.5-E12.5, in the cochleovestibular and facio-acoustic ganglia at E10.5 and the vestibular and spiral ganglia and all the otic epithelia derived from the otocyst at E15.5 and P0. Our data suggest that the B2-r4-Cre transgenic mice provide an important tool for conditional gene manipulation and lineage tracing in the inner ear. In combination with other transgenic lines expressing cre exclusively in the otic vesicle, the relative contributions of the hindbrain, periotic mesenchyme and otic epithelium in otic development can be dissected. Copyright 2009 Wiley-Liss, Inc.

Historical Aspects of Inner Ear Anatomy and Biology that Underlie the Design of Hearing and Balance Prosthetic Devices.

PubMed

Van De Water, Thomas R

2012-11-01

This review presents some of the major historical events that advanced the body of knowledge of the anatomy of the inner ear and its sensory receptors as well as the biology of these receptors that underlies the sensory functions of hearing and balance. This knowledge base of the inner ear's structure/function has been an essential factor for the design and construction of prosthetic devices to aid patients with deficits in their senses of hearing and balance. Prosthetic devices are now available for severely hearing impaired and deaf patients to restore hearing and are known as cochlear implants and auditory brain stem implants. A prosthetic device for patients with balance disorders is being perfected and is in an animal model testing phase with another prosthetic device for controlling intractable dizziness in Meniere's patients currently being evaluated in clinical testing. None of this would have been possible without the pioneering studies and discoveries of the investigators mentioned in this review and with the work of many other talented investigators to numerous to be covered in this review. Copyright © 2012 Wiley Periodicals, Inc.

Pak1 Kinase Maintains Apical Membrane Identity in Epithelia.

PubMed

Aguilar-Aragon, Mario; Elbediwy, Ahmed; Foglizzo, Valentina; Fletcher, Georgina C; Li, Vivian S W; Thompson, Barry J

2018-02-13

Epithelial cells are polarized along their apical-basal axis by the action of the small GTPase Cdc42, which is known to activate the aPKC kinase at the apical domain. However, loss of aPKC kinase activity was reported to have only mild effects on epithelial cell polarity. Here, we show that Cdc42 also activates a second kinase, Pak1, to specify apical domain identity in Drosophila and mammalian epithelia. aPKC and Pak1 phosphorylate an overlapping set of polarity substrates in kinase assays. Inactivating both aPKC kinase activity and the Pak1 kinase leads to a complete loss of epithelial polarity and morphology, with cells losing markers of apical polarization such as Crumbs, Par3/Bazooka, or ZO-1. This function of Pak1 downstream of Cdc42 is distinct from its role in regulating integrins or E-cadherin. Our results define a conserved dual-kinase mechanism for the control of apical membrane identity in epithelia. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

The quest for restoring hearing: Understanding ear development more completely.

PubMed

Jahan, Israt; Pan, Ning; Elliott, Karen L; Fritzsch, Bernd

2015-09-01

Neurosensory hearing loss is a growing problem of super-aged societies. Cochlear implants can restore some hearing, but rebuilding a lost hearing organ would be superior. Research has discovered many cellular and molecular steps to develop a hearing organ but translating those insights into hearing organ restoration remains unclear. For example, we cannot make various hair cell types and arrange them into their specific patterns surrounded by the right type of supporting cells in the right numbers. Our overview of the topologically highly organized and functionally diversified cellular mosaic of the mammalian hearing organ highlights what is known and unknown about its development. Following this analysis, we suggest critical steps to guide future attempts toward restoration of a functional organ of Corti. We argue that generating mutant mouse lines that mimic human pathology to fine-tune attempts toward long-term functional restoration are needed to go beyond the hope generated by restoring single hair cells in postnatal sensory epithelia. © 2015 WILEY Periodicals, Inc.

Airplane Ear

MedlinePlus

... to severe hearing loss Ringing in your ear (tinnitus) Spinning sensation (vertigo) Vomiting resulting from vertigo Bleeding ... complications may include: Permanent hearing loss Ongoing (chronic) tinnitus Prevention Follow these tips to avoid airplane ear: ...

Your Ears

MedlinePlus

... Protect your hearing by wearing earplugs at loud music concerts and around noisy machinery, like in wood ... More on this topic for: Kids Can Loud Music Hurt My Ears? What Is an Ear Infection? ...

Ear examination

MedlinePlus

... ear anatomy Otoscopic exam of the ear References King EF, Couch ME. History, physical examination, and the ... commercial use must be authorized in writing by ADAM Health Solutions. About MedlinePlus Site Map FAQs Customer ...

Inner ear disorders.

PubMed

Smouha, Eric

2013-01-01

To present a framework for the diagnosis and treatment of inner ear disorders, with an emphasis on problems common to neuro-rehabilitation. Disorders of the inner ear can cause hearing loss, tinnitus, vertigo and imbalance. Hearing loss can be conductive, sensorineural, or mixed; conductive hearing loss arises from the ear canal or middle ear, while sensorineural hearing loss arises from the inner ear or auditory nerve. Vertigo is a hallucination of motion, and is the cardinal symptom of vestibular system disease. It should be differentiated from other causes of dizziness: gait imbalance, disequilibrium, lightheadedness (pre-syncope). Vertigo can be caused by problems in the inner ear or central nervous system. The diagnosis of inner ear disorders begins with a targeted physical examination. The initial work-up of hearing loss is made by audiometry, and vertigo by electronystagmography (ENG). Supplemental tests and MRI are obtained when clinically indicated. The clinical pattern and duration of vertigo are the most important clinical features in the diagnosis. Common inner ear causes of vertigo include: vestibular neuritis (sudden, unilateral vestibular loss), Meniere's disease (episodic vertigo), benign paroxysmal positional vertigo (BPPV), and bilateral vestibular loss. Common central nervous system causes of vertigo include: post concussion syndrome, cervical vertigo, vestibular migraine, cerebrovascular disease, and acoustic neuroma. A basic knowledge of vestibular physiology, coupled with a understanding of common vestibular syndromes, will lead to correct diagnosis and treatment in most cases.

Platelet Activating Factor Receptor Activation Improves siRNA Uptake and RNAi Responses in Well-differentiated Airway Epithelia.

PubMed

Krishnamurthy, Sateesh; Behlke, Mark A; Apicella, Michael A; McCray, Paul B; Davidson, Beverly L

2014-07-15

Well-differentiated human airway epithelia present formidable barriers to efficient siRNA delivery. We previously reported that treatment of airway epithelia with specific small molecules improves oligonucleotide uptake and facilitates RNAi responses. Here, we exploited the platelet activating factor receptor (PAFR) pathway, utilized by specific bacteria to transcytose into epithelia, as a trigger for internalization of Dicer-substrate siRNAs (DsiRNA). PAFR is a G-protein coupled receptor which can be engaged and activated by phosphorylcholine residues on the lipooligosaccharide (LOS) of nontypeable Haemophilus influenzae and the teichoic acid of Streptococcus pneumoniae as well as by its natural ligand, platelet activating factor (PAF). When well-differentiated airway epithelia were simultaneously treated with either nontypeable Haemophilus influenzae LOS or PAF and transduced with DsiRNA formulated with the peptide transductin, we observed silencing of both endogenous and exogenous targets. PAF receptor antagonists prevented LOS or PAF-assisted DsiRNA silencing, demonstrating that ligand engagement of PAFR is essential for this process. Additionally, PAF-assisted DsiRNA transfection decreased CFTR protein expression and function and reduced exogenous viral protein levels and titer in human airway epithelia. Treatment with spiperone, a small molecule identified using the Connectivity map database to correlate gene expression changes in response to drug treatment with those associated with PAFR stimulation, also induced silencing. These results suggest that the signaling pathway activated by PAFR binding can be manipulated to facilitate siRNA entry and function in difficult to transfect well-differentiated airway epithelial cells.

Ear Tubes

MedlinePlus

... 1/20th of an inch) that could allow water to enter the middle ear, research studies show no benefit in keeping the ears dry and current guidelines do not recommend routine water precautions. Therefore, you do not need to restrict ...

Active middle ear implant after lateral petrosectomy and radiotherapy for ear cancer.

PubMed

Cristalli, Giovanni; Sprinzl, Georg M; Wolf-Magele, Astrid; Marchesi, Paolo; Mercante, Giuseppe; Spriano, Giuseppe

2014-04-01

Tumor of the temporal bone is a rare disease with a very poor prognosis. Surgery and postoperative radiotherapy are usually the recommended treatments for squamous cell carcinoma (SCC) of the external and middle ear, which may cause conductive hearing loss. The purpose of this study was to evaluate the audiologic results and compliance of active middle ear implant (AMEI) and establish the feasibility of the procedure in a patient treated for middle ear cancer. A 73-year-old patient treated with lateral petrosectomy, neck dissection, reconstruction/obliteration by pedicled pectoralis major myocutaneous flap, and postoperative full dose radiotherapy for external and middle ear SCC was selected for AMEI. Preoperative audiometric and speech audiometry tests were performed on both ears before and after the activation. Pure tone free field audiometry. Binaural free field speech audiogram. Aided pure tone free field audiometry AMEI results show an increase in air conduction. Speech audiogram showed better discrimination scores in AMEI-aided situations. No complications were observed. AMEI after surgery followed by radiotherapy for middle ear cancer is feasible. Acoustic results in obliterated ear are satisfactory.

Ear canal dynamic motion as a source of power for in-ear devices

NASA Astrophysics Data System (ADS)

Delnavaz, Aidin; Voix, Jérémie

2013-02-01

Ear canal deformation caused by temporomandibular joint (jaw joint) activity, also known as "ear canal dynamic motion," is introduced in this paper as a candidate source of power to possibly recharge hearing aid batteries. The geometrical deformation of the ear canal is quantified in 3D by laser scanning of different custom ear moulds. An experimental setup is proposed to measure the amount of power potentially available from this source. The results show that 9 mW of power is available from a 15 mm3 dynamic change in the ear canal volume. Finally, the dynamic motion and power capability of the ear canal are investigated in a group of 12 subjects.

Loss of anion transport without increased sodium absorption characterizes newborn porcine cystic fibrosis airway epithelia

PubMed Central

Chen, Jeng-Haur; Stoltz, David A.; Karp, Philip H.; Ernst, Sarah E.; Pezzulo, Alejandro A.; Moninger, Thomas O.; Rector, Michael V.; Reznikov, Leah R.; Launspach, Janice L.; Chaloner, Kathryn; Zabner, Joseph; Welsh, Michael J.

2011-01-01

SUMMARY Defective transepithelial electrolyte transport is thought to initiate cystic fibrosis (CF) lung disease. Yet, how loss of CFTR affects electrolyte transport remains uncertain. CFTR−/− pigs spontaneously develop lung disease resembling human CF. At birth, their airways exhibit a bacterial host defense defect, but are not inflamed. Therefore, we studied ion transport in newborn nasal and tracheal/bronchial epithelia in tissue, cultures, and in vivo. CFTR−/− epithelia showed markedly reduced Cl− and HCO3− transport. However, in contrast to a widely held view, lack of CFTR did not increase transepithelial Na+ or liquid absorption or reduce periciliary liquid depth. Like human CF, CFTR−/− pigs showed increased amiloride-sensitive voltage and current, but lack of apical Cl− conductance caused the change, not increased Na+ transport. These results indicate that CFTR provides the predominant transcellular pathway for Cl− and HCO3− in porcine airway epithelia, and reduced anion permeability may initiate CF airway disease. PMID:21145458

Motile cilia of human airway epithelia contain hedgehog signaling components that mediate noncanonical hedgehog signaling.

PubMed

Mao, Suifang; Shah, Alok S; Moninger, Thomas O; Ostedgaard, Lynda S; Lu, Lin; Tang, Xiao Xiao; Thornell, Ian M; Reznikov, Leah R; Ernst, Sarah E; Karp, Philip H; Tan, Ping; Keshavjee, Shaf; Abou Alaiwa, Mahmoud H; Welsh, Michael J

2018-02-06

Differentiated airway epithelia produce sonic hedgehog (SHH), which is found in the thin layer of liquid covering the airway surface. Although previous studies showed that vertebrate HH signaling requires primary cilia, as airway epithelia mature, the cells lose primary cilia and produce hundreds of motile cilia. Thus, whether airway epithelia have apical receptors for SHH has remained unknown. We discovered that motile cilia on airway epithelial cells have HH signaling proteins, including patched and smoothened. These cilia also have proteins affecting cAMP-dependent signaling, including Gα i and adenylyl cyclase 5/6. Apical SHH decreases intracellular levels of cAMP, which reduces ciliary beat frequency and pH in airway surface liquid. These results suggest that apical SHH may mediate noncanonical HH signaling through motile cilia to dampen respiratory defenses at the contact point between the environment and the lung, perhaps counterbalancing processes that stimulate airway defenses. Copyright © 2018 the Author(s). Published by PNAS.

Ablation of Coactivator Med1 Switches the Cell Fate of Dental Epithelia to That Generating Hair

PubMed Central

Nguyen, Thai; Sakai, Kiyoshi; He, Bing; Fong, Chak; Oda, Yuko

2014-01-01

Cell fates are determined by specific transcriptional programs. Here we provide evidence that the transcriptional coactivator, Mediator 1 (Med1), is essential for the cell fate determination of ectodermal epithelia. Conditional deletion of Med1 in vivo converted dental epithelia into epidermal epithelia, causing defects in enamel organ development while promoting hair formation in the incisors. We identified multiple processes by which hairs are generated in Med1 deficient incisors: 1) dental epithelial stem cells lacking Med 1 fail to commit to the dental lineage, 2) Sox2-expressing stem cells extend into the differentiation zone and remain multi-potent due to reduced Notch1 signaling, and 3) epidermal fate is induced by calcium as demonstrated in dental epithelial cell cultures. These results demonstrate that Med1 is a master regulator in adult stem cells to govern epithelial cell fate. PMID:24949995

Mate choice in the eye and ear of the beholder? Female multimodal sensory configuration influences her preferences.

PubMed

Ronald, Kelly L; Fernández-Juricic, Esteban; Lucas, Jeffrey R

2018-05-16

A common assumption in sexual selection studies is that receivers decode signal information similarly. However, receivers may vary in how they rank signallers if signal perception varies with an individual's sensory configuration. Furthermore, receivers may vary in their weighting of different elements of multimodal signals based on their sensory configuration. This could lead to complex levels of selection on signalling traits. We tested whether multimodal sensory configuration could affect preferences for multimodal signals. We used brown-headed cowbird ( Molothrus ater ) females to examine how auditory sensitivity and auditory filters, which influence auditory spectral and temporal resolution, affect song preferences, and how visual spatial resolution and visual temporal resolution, which influence resolution of a moving visual signal, affect visual display preferences. Our results show that multimodal sensory configuration significantly affects preferences for male displays: females with better auditory temporal resolution preferred songs that were shorter, with lower Wiener entropy, and higher frequency; and females with better visual temporal resolution preferred males with less intense visual displays. Our findings provide new insights into mate-choice decisions and receiver signal processing. Furthermore, our results challenge a long-standing assumption in animal communication which can affect how we address honest signalling, assortative mating and sensory drive. © 2018 The Author(s).

Cytoskeletal changes in actin and microtubules underlie the developing surface mechanical properties of sensory and supporting cells in the mouse cochlea

PubMed Central

Szarama, Katherine B.; Gavara, Núria; Petralia, Ronald S.; Kelley, Matthew W.; Chadwick, Richard S.

2012-01-01

Correct patterning of the inner ear sensory epithelium is essential for the conversion of sound waves into auditory stimuli. Although much is known about the impact of the developing cytoskeleton on cellular growth and cell shape, considerably less is known about the role of cytoskeletal structures on cell surface mechanical properties. In this study, atomic force microscopy (AFM) was combined with fluorescence imaging to show that developing inner ear hair cells and supporting cells have different cell surface mechanical properties with different developmental time courses. We also explored the cytoskeletal organization of developing sensory and non-sensory cells, and used pharmacological modulation of cytoskeletal elements to show that the developmental increase of hair cell stiffness is a direct result of actin filaments, whereas the development of supporting cell surface mechanical properties depends on the extent of microtubule acetylation. Finally, this study found that the fibroblast growth factor signaling pathway is necessary for the developmental time course of cell surface mechanical properties, in part owing to the effects on microtubule structure. PMID:22573615

Resveratrol inhibits rhinovirus replication and expression of inflammatory mediators in nasal epithelia.

PubMed

Mastromarino, Paola; Capobianco, Daniela; Cannata, Federica; Nardis, Chiara; Mattia, Elena; De Leo, Alessandra; Restignoli, Rossella; Francioso, Antonio; Mosca, Luciana

2015-11-01

Human rhinoviruses (HRV), the cause of common colds, are the most frequent precipitants of acute exacerbation of asthma and chronic obstructive pulmonary disease, as well as causes of other serious respiratory diseases. No vaccine or antiviral agents are available for the prevention or treatment of HRV infection. Resveratrol exerts antiviral effect against different DNA and RNA viruses. The antiviral effect of a new resveratrol formulation containing carboxymethylated glucan was analyzed in H1HeLa cell monolayers and ex vivo nasal epithelia infected with HRV-16. Virus yield was evaluated by plaque assay and expression of viral capsid proteins by Western blot. IL-10, IFN-β, IL-6, IL-8 and RANTES levels were evaluated by ELISA assay. ICAM-1 was assessed by Western blot and immunofluorescence. Resveratrol exerted a high, dose-dependent, antiviral activity against HRV-16 replication and reduced virus-induced secretion of IL-6, IL-8 and RANTES to levels similar to that of uninfected nasal epithelia. Basal levels of IL-6 and RANTES were also significantly reduced in uninfected epithelia confirming an anti-inflammatory effect of the compound. HRV-induced expression of ICAM-1 was reversed by resveratrol. Resveratrol may be useful for a therapeutic approach to reduce HRV replication and virus-induced cytokine/chemokine production. Copyright © 2015 Elsevier B.V. All rights reserved.

External Otitis (Swimmer's Ear)

MedlinePlus

... Debris removal, antibiotic ear drops, keeping water and cotton swabs out of the ear, and pain relievers ... Injuring the ear canal while cleaning it (using cotton swabs) or getting water or irritants, such as ...

Ear Injuries (For Parents)

MedlinePlus

... Inserting something into the ear. Things like a cotton swab, fingernail, or pencil can scratch the ear ... Never stick anything in their ears — not even cotton swabs or their fingers. Regular bathing should be ...

Platelet Activating Factor Receptor Activation Improves siRNA Uptake and RNAi Responses in Well-differentiated Airway Epithelia

PubMed Central

Krishnamurthy, Sateesh; Behlke, Mark A; Apicella, Michael A; McCray, Paul B; Davidson, Beverly L

2014-01-01

Well-differentiated human airway epithelia present formidable barriers to efficient siRNA delivery. We previously reported that treatment of airway epithelia with specific small molecules improves oligonucleotide uptake and facilitates RNAi responses. Here, we exploited the platelet activating factor receptor (PAFR) pathway, utilized by specific bacteria to transcytose into epithelia, as a trigger for internalization of Dicer-substrate siRNAs (DsiRNA). PAFR is a G-protein coupled receptor which can be engaged and activated by phosphorylcholine residues on the lipooligosaccharide (LOS) of nontypeable Haemophilus influenzae and the teichoic acid of Streptococcus pneumoniae as well as by its natural ligand, platelet activating factor (PAF). When well-differentiated airway epithelia were simultaneously treated with either nontypeable Haemophilus influenzae LOS or PAF and transduced with DsiRNA formulated with the peptide transductin, we observed silencing of both endogenous and exogenous targets. PAF receptor antagonists prevented LOS or PAF-assisted DsiRNA silencing, demonstrating that ligand engagement of PAFR is essential for this process. Additionally, PAF-assisted DsiRNA transfection decreased CFTR protein expression and function and reduced exogenous viral protein levels and titer in human airway epithelia. Treatment with spiperone, a small molecule identified using the Connectivity map database to correlate gene expression changes in response to drug treatment with those associated with PAFR stimulation, also induced silencing. These results suggest that the signaling pathway activated by PAFR binding can be manipulated to facilitate siRNA entry and function in difficult to transfect well-differentiated airway epithelial cells. PMID:25025465

Chinchilla middle ear transmission matrix model and middle-ear flexibilitya)

PubMed Central

Ravicz, Michael E.; Rosowski, John J.

2017-01-01

The function of the middle ear (ME) in transforming ME acoustic inputs and outputs (sound pressures and volume velocities) can be described with an acoustic two-port transmission matrix. This description is independent of the load on the ME (cochlea or ear canal) and holds in either direction: forward (from ear canal to cochlea) or reverse (from cochlea to ear canal). A transmission matrix describing ME function in chinchilla, an animal commonly used in auditory research, is presented, computed from measurements of forward ME function: input admittance YTM, ME pressure gain GMEP, ME velocity transfer function HV, and cochlear input admittance YC, in the same set of ears [Ravicz and Rosowski (2012b). J. Acoust. Soc. Am. 132, 2437–2454; (2013a). J. Acoust. Soc. Am. 133, 2208–2223; (2013b). J. Acoust. Soc. Am. 134, 2852–2865]. Unlike previous estimates, these computations require no assumptions about the state of the inner ear, effectiveness of ME manipulations, or measurements of sound transmission in the reverse direction. These element values are generally consistent with physical constraints and the anatomical ME “transformer ratio.” Differences from a previous estimate in chinchilla [Songer and Rosowski (2007). J. Acoust. Soc. Am. 122, 932–942] may be due to a difference in ME flexibility between the two subject groups. PMID:28599566

Chinchilla middle ear transmission matrix model and middle-ear flexibility.

PubMed

Ravicz, Michael E; Rosowski, John J

2017-05-01

The function of the middle ear (ME) in transforming ME acoustic inputs and outputs (sound pressures and volume velocities) can be described with an acoustic two-port transmission matrix. This description is independent of the load on the ME (cochlea or ear canal) and holds in either direction: forward (from ear canal to cochlea) or reverse (from cochlea to ear canal). A transmission matrix describing ME function in chinchilla, an animal commonly used in auditory research, is presented, computed from measurements of forward ME function: input admittance Y TM , ME pressure gain G MEP , ME velocity transfer function H V , and cochlear input admittance Y C , in the same set of ears [Ravicz and Rosowski (2012b). J. Acoust. Soc. Am. 132, 2437-2454; (2013a). J. Acoust. Soc. Am. 133, 2208-2223; (2013b). J. Acoust. Soc. Am. 134, 2852-2865]. Unlike previous estimates, these computations require no assumptions about the state of the inner ear, effectiveness of ME manipulations, or measurements of sound transmission in the reverse direction. These element values are generally consistent with physical constraints and the anatomical ME "transformer ratio." Differences from a previous estimate in chinchilla [Songer and Rosowski (2007). J. Acoust. Soc. Am. 122, 932-942] may be due to a difference in ME flexibility between the two subject groups.

Taking Care of Your Ears

MedlinePlus

... Audiologist Perforated Eardrum What's Hearing Loss? Can Loud Music Hurt My Ears? What Is an Ear Infection? Swimmer's Ear Your Ears What's Earwax? View more About Us Contact Us Partners Editorial Policy Permissions Guidelines Privacy Policy & Terms of Use Notice ...

Middle Ear Infections (For Parents)

MedlinePlus

... Staying Safe Videos for Educators Search English Español Middle Ear Infections KidsHealth / For Parents / Middle Ear Infections What's ... en español Infecciones del oído medio What Are Middle Ear Infections? Ear infections happen when viruses or bacteria ...

Measurements of intracellular calcium signals in polarized primary cultures of normal and cystic fibrosis human airway epithelia.

PubMed

Ribeiro, Carla M P

2011-01-01

The airways are continuously challenged by a variety of stimuli including bacteria, viruses, allergens, and inflammatory factors that act as agonists for G protein-coupled receptors (GPCR). Intracellular calcium (Ca(2+) (i)) mobilization in airway epithelia in response to extracellular stimuli regulates key airway innate defense functions, e.g., Ca(2+)-activated Cl(-) secretion, ciliary beating, mucin secretion, and inflammatory responses. Because Ca(2+) (i) mobilization in response to luminal stimuli is larger in CF vs. normal human airway epithelia, alterations in Ca(2+) (i) signals have been associated with the pathogenesis of CF airway disease. Hence, assessment of Ca(2+) (i) signaling has become an important area of CF research. This chapter will focus on measurements of cytoplasmic and mitochondrial Ca(2+) signals resulting from GPCR activation in polarized primary cultures of normal and CF human bronchial epithelia (HBE).

Cauliflower ear dissection.

PubMed

Fujiwara, Masao; Suzuki, Ayano; Nagata, Takeshi; Fukamizu, Hidekazu

2011-11-01

Cauliflower ear (CE) is caused by repeated direct trauma to the external ear. Surgical correction of an established CE is one of the most challenging problems in ear reconstruction. However, no reports have clarified the dissection of an established CE in detail. In this report, the dissection of a CE is described based on macroscopic, microscopic and imaging features. Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Mechanisms of Membrane Transport of Folates into Cells and Across Epithelia

PubMed Central

Zhao, Rongbao; Diop-Bove, Ndeye; Visentin, Michele; Goldman, I. David

2013-01-01

Until recently, the transport of folates into cells and across epithelia has been interpreted primarily within the context of two transporters with high affinity and specificity for folates, the reduced folate carrier and the folate receptors. However, there were discrepancies between the properties of these transporters and characteristics of folate transport in many tissues, most notably the intestinal absorption of folates, in terms of pH dependency and substrate specificity. With the recent cloning of the proton-coupled folate transporter (PCFT) and the demonstration that this transporter is mutated in hereditary folate malabsorption, an autosomal recessive disorder, the molecular basis for this low-pH transport activity is now understood. This review focuses on the properties of PCFT and briefly addresses the two other folate-specific transporters along with other facilitative and ATP-binding cassette (ABC) transporters with folate transport activities. The role of these transporters in the vectorial transport of folates across epithelia is considered. PMID:21568705

Body-conscious Shakespeare: sensory disturbances in troubled characters.

PubMed

Heaton, Kenneth W

2011-12-01

It is widely accepted that Shakespeare was unique in the range of his insights into the human mind, but the way his characters reveal their mental states through bodily sensations has not been systematically explored. The author has searched for these phenomena in the 42 major works of Shakespeare and in 46 genre-matched works by his contemporaries, and in this paper the author focuses on sensory changes other than those involving vision, taste, the heart and the alimentary tract (all considered in other papers). Vertigo is experienced by five distressed Shakespearean characters, all men, but not at all by the other writers' characters. Breathlessness, probably representing hyperventilation, occurs eleven times in Shakespeare's works but only twice in the other writers' works. Fatigue, expressing grief, is articulated by several Shakespearean characters including Hamlet. It features less often in the others' works. Deafness at a time of high emotion is mentioned by Shakespeare several times but usually by a character 'turning a deaf ear', consciously or unconsciously. To the other writers, ears show emotion only by burning or itching. Blunting of touch and pain and their opposites of hypersensitivity to touch and pain are all to be found in Shakespeare's works when a character is distressed or excited, but not so with his contemporaries' works. Faint feelings and cold feelings are also more common in the works of Shakespeare. Overall, therefore, Shakespeare was exceptional in his use of sensory disturbances to express emotional upset. This may be a conscious literary device or a sign of exceptional awareness of bodily sensations.

Localization of efferent neurotransmitters in the inner ear of the homozygous Bronx waltzer mutant mouse.

PubMed

Kong, W J; Scholtz, A W; Hussl, B; Kammen-Jolly, K; Schrott-Fischer, A

2002-05-01

Naturally occurring mutant mice provide an excellent model for the study of genetic malformations of the inner ear. Mice homozygous for the Bronx waltzer (bv/bv) mutation are severely hearing impaired or deaf and exhibit a 'waltzing' gait. Functional aspects of cochlear and vestibular efferents in the bv/bv mutant mouse are not well known. The present study was designed to evaluate several candidates of efferent neurotransmitters or neuromodulators including choline acetyltransferase (ChAT), gamma-aminobutyric acid (GABA), and calcitonin gene-related peptide (CGRP) in the inner ear of the bv/bv mutant mouse. Ultrastructural investigations at both light and electron microscopic level were performed. Ultrastructural morphologic evaluations of the cochlea and the vestibular end-organs were also undertaken. It is demonstrated that ChAT, GABA and CGRP immunoreactivities are present in the cochlea and in vestibular end-organs of bv/bv mutant mice. In the organ of Corti, immunoreactivity of ChAT, GABA and CGRP is confined to the inner spiral fibers, tunnel-crossing fibers, and the vesiculated nerve endings synapsing with outer hair cells. Interestingly, immunoreactivity was detectable even where inner hair cells appeared missing. Results also revealed malformations of the outer hair cells with synaptic contacts to efferent nerve endings consistently intact. In the neurosensory epithelia of the vestibular end-organs, the presence of ChAT, GABA, and CGRP immunoreactivity was localized at the vestibular efferents, with the exception of the macula of saccule. In one 8-month-old macula of utricle where the depletion of hair cells appeared highest, ChAT immunostaining was still discernible. Ultrastructural investigation demonstrated that vesiculated efferent nerve endings make synaptic contact with the outer hair cells in the organ of Corti and with type II hair cells in the vestibular end-organs. The present study provides further support that the efferent system in the bv

Estimation of outer-middle ear transmission using DPOAEs and fractional-order modeling of human middle ear

NASA Astrophysics Data System (ADS)

Naghibolhosseini, Maryam

Our ability to hear depends primarily on sound waves traveling through the outer and middle ear toward the inner ear. Hence, the characteristics of the outer and middle ear affect sound transmission to/from the inner ear. The role of the middle and outer ear in sound transmission is particularly important for otoacoustic emissions (OAEs), which are sound signals generated in a healthy cochlea, and recorded by a sensitive microphone placed in the ear canal. OAEs are used to evaluate the health and function of the cochlea; however, they are also affected by outer and middle ear characteristics. To better assess cochlear health using OAEs, it is critical to quantify the impact of the outer and middle ear on sound transmission. The reported research introduces a noninvasive approach to estimate outer-middle ear transmission using distortion product otoacoustic emissions (DPOAEs). In addition, the role of the outer and middle ear on sound transmission was investigated by developing a physical/mathematical model, which employed fractional-order lumped elements to include the viscoelastic characteristics of biological tissues. Impedance estimations from wideband refectance measurements were used for parameter fitting of the model. The model was validated comparing its estimates of the outer-middle ear sound transmission with those given by DPOAEs. The outer-middle ear transmission by the model was defined as the sum of forward and reverse outer-middle ear transmissions. To estimate the reverse transmission by the model, the probe-microphone impedance was calculated through estimating the Thevenin-equivalent circuit of the probe-microphone. The Thevenin-equivalent circuit was calculated using measurements in a number of test cavities. Such modeling enhances our understanding of the roles of different parts of the outer and middle ear and how they work together to determine their function. In addition, the model would be potentially helpful in diagnosing pathologies of

Comparison of two Chinese medical herbs, Huangbai and Qianniuzi, on influence of short circuit current across the rat intestinal epithelia.

PubMed

Tsai, Jong-Chang; Tsai, Shuli; Chang, Weng-Cheng

2004-07-01

Huangbai (Phellodendron spec.) and Qianniuzi (Pharbitis spec.) are two traditional Chinese medical herbs used for anti-diarrheal and laxative agents, respectively. Ethanol and water extracts of these two herbs were prepared and effects of the extracts on ion transport of the rat intestinal epithelia were studied. For measuring changes of the short circuit current across the epithelia, the rat intestinal epithelia were mounted in the Ussing chamber and attached with voltage/current clamp. The intestinal epithelia were firstly activated by serosal administration of 5 microM forskolin. As current raised and being stable, extracts of these herbs were added, respectively, and changes in the short circuit current were recorded. Ethanol extract of Huangbai attenuated the current increment; on the contrary, ethanol extract of Qianniuzi augmented the current increment additionally. Water extracts of the two herbs showed minor effects on the current in comparison to ethanol extracts. The results provide evidences to reveal the pharmacological mechanism of the two Chinese medical herbs on the intestinal tissue.

Prenatal evaluation of the middle ear and diagnosis of middle ear hypoplasia using MRI.

PubMed

Katorza, Eldad; Nahama-Allouche, Catherine; Castaigne, Vanina; Gonzales, Marie; Galliani, Eva; Marlin, Sandrine; Jouannic, Jean-Marie; Rosenblatt, Jonathan; le Pointe, Hubert Ducou; Garel, Catherine

2011-05-01

Analysis of the middle ear with fetal MRI has not been previously reported. To show the contribution of fetal MRI to middle ear imaging. The tympanic cavity was evaluated in 108 fetal cerebral MRI examinations (facial and/or cerebral malformation excluded) and in two cases, one of Treacher Collins syndrome (case 1) and the other of oculo-auriculo-vertebral (OUV) spectrum (case 2) with middle ear hypoplasia identified by MRI at 27 and 36 weeks' gestation, respectively. In all 108 fetuses (mean gestational age 32.5 weeks), the tympanic cavity and T2 hypointensity related to the ossicles were well visualised on both sides. Case 1 had micro/retrognathia and bilateral external ear deformity and case 2 had retrognathism with a left low-set and deformed ear. MRI made it possible to recognize the marked hypoplasia of the tympanic cavity, which was bilateral in case 1 and unilateral in case 2. Both syndromes are characterized by craniofacial abnormalities including middle ear hypoplasia, which cannot be diagnosed with US. The middle ear cavity can be visualized with fetal MRI. We emphasize the use of this imaging modality in the diagnosis of middle ear hypoplasia.

EFFECTS OF INGESTED ARSENIC ON DNA AND CHROMOSOME IN HUMAN EXFOLIATED EPITHELIA

EPA Science Inventory

Effects of Ingested Arsenic on DNA and Chromosome in Human Exfoliated Epithelia

Judy L. Mumford, Human Studies Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711

Arsenic...

The thermosensitive TRPV3 channel contributes to rapid wound healing in oral epithelia.

PubMed

Aijima, Reona; Wang, Bing; Takao, Tomoka; Mihara, Hiroshi; Kashio, Makiko; Ohsaki, Yasuyoshi; Zhang, Jing-Qi; Mizuno, Atsuko; Suzuki, Makoto; Yamashita, Yoshio; Masuko, Sadahiko; Goto, Masaaki; Tominaga, Makoto; Kido, Mizuho A

2015-01-01

The oral cavity provides an entrance to the alimentary tract to serve as a protective barrier against harmful environmental stimuli. The oral mucosa is susceptible to injury because of its location; nonetheless, it has faster wound healing than the skin and less scar formation. However, the molecular pathways regulating this wound healing are unclear. Here, we show that transient receptor potential vanilloid 3 (TRPV3), a thermosensitive Ca(2+)-permeable channel, is more highly expressed in murine oral epithelia than in the skin by quantitative RT-PCR. We found that temperatures above 33°C activated TRPV3 and promoted oral epithelial cell proliferation. The proliferation rate in the oral epithelia of TRPV3 knockout (TRPV3KO) mice was less than that of wild-type (WT) mice. We investigated the contribution of TRPV3 to wound healing using a molar tooth extraction model and found that oral wound closure was delayed in TRPV3KO mice compared with that in WT mice. TRPV3 mRNA was up-regulated in wounded tissues, suggesting that TRPV3 may contribute to oral wound repair. We identified TRPV3 as an essential receptor in heat-induced oral epithelia proliferation and wound healing. Our findings suggest that TRPV3 activation could be a potential therapeutic target for wound healing in skin and oral mucosa. © FASEB.

The constricted ear.

PubMed

Paredes, Alfredo A; Williams, J Kerwin; Elsahy, Nabil I

2002-04-01

The constricted ear may be described best as a pursestring closure of the ear. The deformity may include lidding of the upper pole with downward folding, protrusion of the concha, decreased vertical height, and low ear position relative to the face. The goals of surgical correction should include obtaining symmetry and correcting the intra-auricular anatomy. The degree of intervention is based on the severity of the deformity and may range from simple repositioning, soft tissue rearrangement, or manipulation of the cartilage. Multiple surgical techniques are described.

Inner ear manifestations in CHARGE: Abnormalities, treatments, animal models, and progress toward treatments in auditory and vestibular structures.

PubMed

Choo, Daniel I; Tawfik, Kareem O; Martin, Donna M; Raphael, Yehoash

2017-12-01

The inner ear contains the sensory organs for hearing and balance. Both hearing and balance are commonly affected in individuals with CHARGE syndrome (CS), an autosomal dominant condition caused by heterozygous pathogenic variants in the CHD7 gene. Semicircular canal dysplasia or aplasia is the single most prevalent feature in individuals with CHARGE leading to deficient gross motor skills and ambulation. Identification of CHD7 as the major gene affected in CHARGE has enabled acceleration of research in this field. Great progress has been made in understanding the role of CHD7 in the development and function of the inner ear, as well as in related organs such as the middle ear and auditory and vestibular neural pathways. The goals of current research on CHD7 and CS are to (a) improve our understanding of the pathology caused by CHD7 pathogenic variants and (b) to provide better tools for prognosis and treatment. Current studies utilize cells and whole animals, from flies to mammals. The mouse is an excellent model for exploring mechanisms of Chd7 function in the ear, given the evolutionary conservation of ear structure, function, Chd7 expression, and similarity of mutant phenotypes between mice and humans. Newly recognized developmental functions for mouse Chd7 are shedding light on how abnormalities in CHD7 might lead to CS symptoms in humans. Here we review known human inner ear phenotypes associated with CHD7 pathogenic variants and CS, summarize progress toward diagnosis and treatment of inner ear-related pathologies, and explore new avenues for treatment based on basic science discoveries. © 2017 Wiley Periodicals, Inc.

Exploring the mammalian sensory space: co-operations and trade-offs among senses.

PubMed

Nummela, Sirpa; Pihlström, Henry; Puolamäki, Kai; Fortelius, Mikael; Hemilä, Simo; Reuter, Tom

2013-12-01

The evolution of a particular sensory organ is often discussed with no consideration of the roles played by other senses. Here, we treat mammalian vision, olfaction and hearing as an interconnected whole, a three-dimensional sensory space, evolving in response to ecological challenges. Until now, there has been no quantitative method for estimating how much a particular animal invests in its different senses. We propose an anatomical measure based on sensory organ sizes. Dimensions of functional importance are defined and measured, and normalized in relation to animal mass. For 119 taxonomically and ecologically diverse species, we can define the position of the species in a three-dimensional sensory space. Thus, we can ask questions related to possible trade-off vs. co-operation among senses. More generally, our method allows morphologists to identify sensory organ combinations that are characteristic of particular ecological niches. After normalization for animal size, we note that arboreal mammals tend to have larger eyes and smaller noses than terrestrial mammals. On the other hand, we observe a strong correlation between eyes and ears, indicating that co-operation between vision and hearing is a general mammalian feature. For some groups of mammals we note a correlation, and possible co-operation between olfaction and whiskers.

Gustatory otalgia and wet ear syndrome: a possible cross-innervation after ear surgery.

PubMed

Saito, H

1999-04-01

The chorda tympani and Arnold's nerves have close approximation to each other and their cross-innervation is possible after ear surgery. A retrospective study was performed with a temporal bone pathology case and two clinical cases as representatives of such a possibility. Patients had severe otalgia and wet ear during gustatory stimulation. A temporal bone pathology case was studied under a light microscope. Earache and/or wet ear were provoked during gustatory stimulation. Wet ear was tested with iodine-starch reaction after the subject tasted lemon juice. The temporal bone specimen has clusters of regenerated fibers in the tympanic cavity in the area of the chorda tympani and Arnold's nerves, suggesting a possibility of mixing. There are regenerated fibers in the iter chordae anterius, showing successful bridging of the chorda tympani nerves across a long gap. Detachment of the skin over the operated mastoid bowl obscured signs in one clinical case. Another clinical case of gustatory wet ear showed objective evidence of cross-innervation with iodine-starch reaction. The detachment procedure and iodine-starch reaction were the proofs that the signs were related to regenerated fibers. This is the first report of gustatory otalgia and wet ear after ear surgery.

Being a Parent's Eyes and Ears: Emotional Literacy and Empathy of Children Whose Parents Have a Sensory Disability

ERIC Educational Resources Information Center

Eden, Sigal; Romi, Shlomo; Braun Aviyashar, Einat

2017-01-01

Children of parents with sensory disability may feel that their experience helped nurture their sense of empathy. The study was designed to examine the connection between parents' sensory disability (visual disability to blindness and hearing disability to deafness) and the empathy and emotional literacy of their non-sensory-disabled children.…

Ear drainage culture

MedlinePlus

... needed. Your health care provider will use a cotton swab to collect the sample from inside the ... Using a cotton swab to take a sample of drainage from the outer ear is not painful. However, ear pain may ...

Ongoing cell death and immune influences on regeneration in the vestibular sensory organs

NASA Technical Reports Server (NTRS)

Warchol, M. E.; Matsui, J. I.; Simkus, E. L.; Ogilive, J. M.

2001-01-01

Hair cells in the vestibular organs of birds have a relatively short life span. Mature hair cells appear to die spontaneously and are then quickly replaced by new hair cells that arise from the division of epithelial supporting cells. A similar regenerative mechanism also results in hair cell replacement after ototoxic damage. The cellular basis of hair cell turnover in the avian ear is not understood. We are investigating the signaling pathways that lead to hair cell death and the relationship between ongoing cell death and cell production. In addition, work from our lab and others has demonstrated that the avian inner ear contains a resident population of macrophages and that enhanced numbers of macrophages are recruited to sites of hair cells lesions. Those observations suggest that macrophages and their secretory products (cytokines) may be involved in hair cell regeneration. Consistent with that suggestion, we have found that treatment with the anti-inflammatory drug dexamethasone reduces regenerative cell proliferation in the avian ear, and that certain macrophage-secreted cytokines can influence the proliferation of vestibular supporting cells and the survival of statoacoustic neurons. Those results suggest a role for the immune system in the process of sensory regeneration in the inner ear.

HIV Exposure to the Epithelia in Ectocervical and Colon Tissues Induces Inflammatory Cytokines Without Tight Junction Disruption

PubMed Central

Sankapal, Soni; Gupta, Phalguni; Ratner, Deena; Ding, Ming; Shen, Chengli; Sanyal, Anwesha; Stolz, Donna; Cu-Uvin, Susan; Ramratnam, Bharat

2016-01-01

Abstract Epithelial cells in human cervical and colonic mucosa do not express HIV receptor. However, HIV transmission occurs across the unbreached epithelia by an unknown mechanism. In this study, the effect of HIV exposure on tight junction (TJ) and cytokine production in ectocervical and colon mucosal epithelia in tissue biopsies was investigated in an organ culture model. After HIV exposure, the distribution patterns and quantities of epithelial TJ and adherens proteins were evaluated by immunofluorescence staining followed by confocal microscopy. Cytokine mRNA in the mucosal epithelia was also evaluated by real-time reverse transcription–polymerase chain reaction (RT-PCR). HIV transmission was evaluated by measuring p24 production in culture supernatant. Our results showed there were no significant changes in the distribution and quantities of epithelial TJ/adherens junction (AJ) proteins after exposure to HIV. However, higher levels of CXCL10 and CXCL11 mRNA expression were detected in HIV-exposed ectocervical epithelia. In case of colon mucosa, higher levels of CXCL10 and IL-6 mRNA expression were detected in HIV-exposed colon mucosa. Our study suggests that HIV induces cytokine production in epithelial cells, which may facilitate HIV transmission by recruiting HIV target cells in the submucosal region. Furthermore, HIV transmission may not occur through epithelial TJ/AJ disruption. PMID:27153934

Ear infection - chronic

MedlinePlus

Middle ear infection - chronic; Otitis media - chronic; Chronic otitis media; Chronic ear infection ... Chole RA. Chronic otitis media, mastoiditis, and petrositis. In: Flint PW, Haughey BH, Lund V, et al, eds. Cummings Otolaryngology: Head & Neck Surgery . 6th ed. ...

Chinchilla middle-ear admittance and sound power: High-frequency estimates and effects of inner-ear modifications

PubMed Central

Ravicz, Michael E.; Rosowski, John J.

2012-01-01

The middle-ear input admittance relates sound power into the middle ear (ME) and sound pressure at the tympanic membrane (TM). ME input admittance was measured in the chinchilla ear canal as part of a larger study of sound power transmission through the ME into the inner ear. The middle ear was open, and the inner ear was intact or modified with small sensors inserted into the vestibule near the cochlear base. A simple model of the chinchilla ear canal, based on ear canal sound pressure measurements at two points along the canal and an assumption of plane-wave propagation, enables reliable estimates of YTM, the ME input admittance at the TM, from the admittance measured relatively far from the TM. YTM appears valid at frequencies as high as 17 kHz, a much higher frequency than previously reported. The real part of YTM decreases with frequency above 2 kHz. Effects of the inner-ear sensors (necessary for inner ear power computation) were small and generally limited to frequencies below 3 kHz. Computed power reflectance was ∼0.1 below 3.5 kHz, lower than with an intact ME below 2.5 kHz, and nearly 1 above 16 kHz. PMID:23039439

Ccdc85C, a causative protein for hydrocephalus and subcortical heterotopia, is expressed in the systemic epithelia with proliferative activity in rats.

PubMed

Tanaka, Natsuki; Izawa, Takeshi; Takenaka, Shigeo; Yamate, Jyoji; Kuwamura, Mitsuru

2015-07-01

Coiled-coil domain containing 85c (Ccdc85c) is a causative gene for spontaneous mutant mouse with non-obstructive hydrocephalus and subcortical heterotopia. Detailed functions of Ccdc85C protein have not been clarified. To reveal roles of Ccdc85C, we examined the distribution and expression pattern of Ccdc85C in the systemic developing organs in rats. Ccdc85C was expressed in various simple epithelia but not stratified epithelia. In the various epithelia, Ccdc85C was localized at cell-cell junctions and its expression was strong at apical junctions. Furthermore, intense expression was seen at developing period and gradually decreased with advancing development. Distribution of Ccdc85C coincides with that of proliferating epithelial cells. These results suggest that Ccdc85C plays an important role in the proliferative property of simple epithelia.

Chloride transporting capability of Calu-3 epithelia following persistent knockdown of the cystic fibrosis transmembrane conductance regulator, CFTR

PubMed Central

MacVinish, L J; Cope, G; Ropenga, A; Cuthbert, A W

2007-01-01

Background and purpose: Calu-3 cells are derived from serous cells of human lung submucosal glands, a prime target for therapy in cystic fibrosis (CF). Calu-3 cells can be cultured to form epithelia capable of transepithelial transport of chloride. A CF Calu-3 cell is not available. Experimental approach: A retroviral vector was used to cause persistent down regulation of CFTR using siRNA methodology, in Calu-3 cells. A Calu-3 cell line with CFTR content less than 5% of the original line has been established. Epithelia grown using the modified cells have been used in comparative studies of transporting capability. Key results: All aspects of cAMP activated chloride secretion were attenuated in the epithelia with reduced CFTR content. However transporting capability was reduced less than the CFTR content. From studies with the CFTR channel inhibitor, GlyH-101, it was concluded that wild type Calu-3 cells have a reserve of CFTR channels not located in the membrane, but available for replacement, while in the modified Calu-3 cell line there was little or no reserve. Lubiprostone, a putative ClC-2 activator, increased transepithelial chloride secretion in both modified and wild type Calu-3 epithelia. Modified Calu-3 epithelia with the residual CFTR currents blocked with GlyH-101 responded equally well to lubiprostone as those without the blocking agent. Conclusions and implications: It appears that lubiprostone is capable of stimulating a non-CFTR dependent transepithelial chloride secretion in Calu-3 monolayers, with obvious implications for CF therapy. Cell lines, however, do not always reflect the behaviour of the native tissue with integrity. PMID:17339840

ADAM10 and γ-secretase regulate sensory regeneration in the avian vestibular organs.

PubMed

Warchol, Mark E; Stone, Jennifer; Barton, Matthew; Ku, Jeffrey; Veile, Rose; Daudet, Nicolas; Lovett, Michael

2017-08-01

The loss of sensory hair cells from the inner ear is a leading cause of hearing and balance disorders. The mammalian ear has a very limited ability to replace lost hair cells, but the inner ears of non-mammalian vertebrates can spontaneously regenerate hair cells after injury. Prior studies have shown that replacement hair cells are derived from epithelial supporting cells and that the differentiation of new hair cells is regulated by the Notch signaling pathway. The present study examined molecular influences on regeneration in the avian utricle, which has a particularly robust regenerative ability. Chicken utricles were placed in organotypic culture and hair cells were lesioned by application of the ototoxic antibiotic streptomycin. Cultures were then allowed to regenerate in vitro for seven days. Some specimens were treated with small molecule inhibitors of γ-secretase or ADAM10, proteases which are essential for transmission of Notch signaling. As expected, treatment with both inhibitors led to increased numbers of replacement hair cells. However, we also found that inhibition of both proteases resulted in increased regenerative proliferation. Subsequent experiments showed that inhibition of γ-secretase or ADAM10 could also trigger proliferation in undamaged utricles. To better understand these phenomena, we used RNA-Seq profiling to characterize changes in gene expression following γ-secretase inhibition. We observed expression patterns that were consistent with Notch pathway inhibition, but we also found that the utricular sensory epithelium contains numerous γ-secretase substrates that might regulate cell cycle entry and possibly supporting cell-to-hair cell conversion. Together, our data suggest multiple roles for γ-secretase and ADAM10 in vestibular hair cell regeneration. Copyright © 2017. Published by Elsevier Inc.

Reactivity of Acetylcholine Esterase in inner Ear Maculae of Fish after Development at Hypergravity

NASA Astrophysics Data System (ADS)

Feucht, I.; Hilbig, R.; Anken, R.

It has been shown earlier that the growth of inner ear otoliths of larval fish is (among other environmental factors) guided by the gravity vector. This guidance most probably is effected by the efferent vestibular system in the brainstem, because a transection of the nervus vestibularis has been shown to effect a cessation of the supply of calcium to the otoliths. The efferent innervation of fish inner ear maculae uses the synaptic transmitter acetylcholine (ACh). Therefore, we were - in order to further assess the role of the efferent system for otolith growth - prompted to determine ACh esterase-reactivity in the sensory epithelium of the utricle and the saccule (as well as in a non-gravity relevant brain region for control) in larval cichlid fish (Oreochromis mossambicus), which had been maintained at hypergravity during their development. The respective data will be communicated at the meeting. Acknowledgement: This work was financially supported by the German Aerospace Center (DLR) (FKZ: 50 WB 9997).

Influence of Sensory Dependence on Postural Control

NASA Technical Reports Server (NTRS)

Santana, Patricia A.; Mulavara, Ajitkumar P.; Fiedler, Matthew J.

2011-01-01

The current project is part of an NSBRI funded project, "Development of Countermeasures to Aid Functional Egress from the Crew Exploration Vehicle Following Long-Duration Spaceflight." The development of this countermeasure is based on the use of imperceptible levels of electrical stimulation to the balance organs of the inner ear to assist and enhance the response of a person s sensorimotor function. These countermeasures could be used to increase an astronaut s re-adaptation rate to Earth s gravity following long-duration space flight. The focus of my project is to evaluate and examine the correlation of sensory preferences for vision and vestibular systems. Disruption of the sensorimotor functions following space flight affects posture, locomotion and spatial orientation tasks in astronauts. The Group Embedded Figures Test (GEFT), the Rod and Frame Test (RFT) and the Computerized Dynamic Posturography Test (CDP) are measurements used to examine subjects visual and vestibular sensory preferences. The analysis of data from these tasks will assist in relating the visual dependence measures recognized in the GEFT and RFT with vestibular dependence measures recognized in the stability measures obtained during CDP. Studying the impact of sensory dependence on the performance in varied tasks will help in the development of targeted countermeasures to help astronauts readapt to gravitational changes after long duration space flight.

Self-ear cleaning practices and the associated risk of ear injuries and ear-related symptoms in a group of university students.

PubMed

Khan, Nasim Banu; Thaver, Sivashnee; Govender, Samantha Marlene

2017-12-31

Self-ear cleaning is the insertion of objects into the ear canal to clean it, a widespread practice that has the potential to compromise its integrity as a natural, selfcleansing mechanism, and a risk factor for possible injuries. The practice is common among young adults and highest in university than any other graduates. This study aimed to determine the self-ear cleaning practices and associated risk of injury and related symptoms in undergraduate students at KwaZulu-Natal University. The descriptive survey utilized a self-administered questionnaire. Of the 206 participants that responded, 98% engaged in self-ear cleaning, with 75% indicating that it was beneficial. The commonest method (79.6%) being the use of cotton buds, with an associated injury rate of 2.4%. There was no statistically significant associations between those who used or did not use cotton buds and the symptoms experienced. The complications indicate that self-ear cleaning does pose a risk for injury, necessitating more community information and education.

Theory of forward and reverse middle-ear transmission applied to otoacoustic emissions in infant and adult ears

PubMed Central

Keefe, Douglas H.; Abdala, Carolina

2008-01-01

The purpose of this study is to understand why otoacoustic emission (OAE) levels are higher in normal-hearing human infants relative to adults. In a previous study, distortion product (DP) OAE input/output (I/O) functions were shown to differ at f2=6 kHz in adults compared to infants through 6 months of age. These DPOAE I/O functions were used to noninvasively assess immaturities in forward/reverse transmission through the ear canal and middle ear [Abdala, C., and Keefe, D. H., (2006). J. Acoust Soc. Am. 120, 3832–3842]. In the present study, ear-canal reflectance and DPOAEs measured in the same ears were analyzed using a scattering-matrix model of forward and reverse transmission in the ear canal, middle ear, and cochlea. Reflectance measurements were sensitive to frequency-dependent effects of ear-canal and middle-ear transmission that differed across OAE type and subject age. Results indicated that DPOAE levels were larger in infants mainly because the reverse middle-ear transmittance level varied with ear-canal area, which differed by more than a factor of 7 between term infants and adults. The forward middle-ear transmittance level was −16 dB less in infants, so that the conductive efficiency was poorer in infants than adults. PMID:17348521

Red ear syndrome.

PubMed

Purdy, R Allan; Dodick, David W

2007-08-01

The red ear syndrome is a rare syndrome originally described by Lance in 1994. It involves pain in and around the ear and associated autonomic phenomena, the most significant of which is cutaneous erythema of the ear ipsilateral to the pain and obvious to the patient and examiner during the attack. It may well represent an auriculo-autonomic cephalgia and/or be part of the group of disorders recognized as trigeminal autonomic cephalalgias. As a syndrome, it still lacks specificity in regard to etiology, mechanisms, and treatment but is important to recognize clinically because of its associations.

Could ionizing radiation forestall cauliflower ear?

PubMed

Hwang, K; Kim, C W; Lee, S I; Park, I S; Kim, W C; Loh, J J

2001-02-01

Repeated trauma to the ear very often results in "cauliflower ear." Many methods have been suggested to prevent an injured ear from demonstrating a cauliflowerlike deformity. The principles of treatment are evacuation of the hematoma, control of the reaccumulation of fluid, and maintenance of the cartilage contour. The authors studied the effect of ionizing radiation on deformed rabbit ears induced by repeated trauma. Twenty ears (10 rabbits) were used in the experiment. The animals were divided into four groups (control, preradiation, low dose, and high dose). Hematoma was produced by pounding the lateral side of the auricle 10 times with a 50-g weight at a height of 15 cm. The thickness of the injured and uninjured sites was measured, and histological analysis was performed for each group. The thickness of the ears of the irradiated groups was significantly less than the control group. The authors think that radiation treatment of repeatedly injured ears could prevent ear deformity, and could possibly be an adjunctive form of management of cauliflower ear in addition to hematoma evacuation and compression therapy.

Binding of [35S]saccharin to a protein fraction of rat tongue epithelia.

PubMed

Shimazaki, K; Sato, M; Takegami, T

1981-11-05

The binding of [35S]saccharin to ammonium sulfate fractions from homogenates of rat tongue epithelia was measured by equilibrium dialysis. The 40--60% saturated ammonium sulfate fraction from the buffer-soluble fraction had the highest saccharin-binding activity. Binding of [35S]saccharin to the 40--60% ammonium sulfate fraction was inhibited by unlabeled saccharin sodium salt. The inhibition increased with increasing unlabeled saccharin concentration and was nearly complete above 10 mM. [35S]Saccharin binding to the 40--60% ammonium sulfate fraction extracted from the tongue epithelia was inhibited by glucose, lactose and sucrose, while binding to similar fractions from tongue muscle was not affected by these sugars. The inhibition of binding of labeled saccharin to the epithelial fraction increased with increasing glucose concentrations. About 35% of the binding was inhibited by 1 M glucose. No significant difference in the amount of inhibition was seen among the three sugars at 0.1 M. The 40--60% ammonium sulfate fraction from tongue epithelium devoid of taste buds bound much less [35S]saccharin than did a similar fraction from epithelium with taste buds. Binding of [35S]saccharin by the preparation from epithelium devoid of taste buds was not inhibited by glucose. The results provide evidence that the 40--60% ammonium sulfate fraction from tongue epithelia with taste buds contains a protein which binds saccharin and sugars. We hypothesize that it is a sweet taste receptor protein.

Ear tube insertion

MedlinePlus

... eardrum may cause some hearing loss. But most children do not have long-term damage to their hearing or speech, even when the ... not go away with treatment, or if a child has many ear infections ... or that damages nearby nerves Injury to the ear after sudden ...

Whole-mount Confocal Microscopy for Adult Ear Skin: A Model System to Study Neuro-vascular Branching Morphogenesis and Immune Cell Distribution.

PubMed

Yamazaki, Tomoko; Li, Wenling; Mukouyama, Yoh-Suke

2018-03-29

Here, we present a protocol of a whole-mount adult ear skin imaging technique to study comprehensive three-dimensional neuro-vascular branching morphogenesis and patterning, as well as immune cell distribution at a cellular level. The analysis of peripheral nerve and blood vessel anatomical structures in adult tissues provides some insights into the understanding of functional neuro-vascular wiring and neuro-vascular degeneration in pathological conditions such as wound healing. As a highly informative model system, we have focused our studies on adult ear skin, which is readily accessible for dissection. Our simple and reproducible protocol provides an accurate depiction of the cellular components in the entire skin, such as peripheral nerves (sensory axons, sympathetic axons, and Schwann cells), blood vessels (endothelial cells and vascular smooth muscle cells), and inflammatory cells. We believe this protocol will pave the way to investigate morphological abnormalities in peripheral nerves and blood vessels as well as the inflammation in the adult ear skin under different pathological conditions.

Anomalies of the middle and inner ear.

PubMed

Rodriguez, Kimsey; Shah, Rahul K; Kenna, Margaret

2007-02-01

The development of the middle and inner ear highlights the intricacy of embryology. As early as 3 weeks after fertilization, the inner ear begins taking form. This process, along with development of the middle ear, continues throughout gestation. At birth, the middle ear, inner ear, and associated structures are almost adult size. An understanding of the embryologic development of the ear serves as a foundation for evaluating and managing congenital malformations of these structures. The focus of this article is the normal, abnormal, and arrested development of the middle and inner ear, with a clinical emphasis on malformed middle and inner ear structures and a discussion of associated syndromes.

Maintained expression of the planar cell polarity molecule Vangl2 and reformation of hair cell orientation in the regenerating inner ear.

PubMed

Warchol, Mark E; Montcouquiol, Mireille

2010-09-01

The avian inner ear possesses a remarkable ability to regenerate sensory hair cells after ototoxic injury. Regenerated hair cells possess phenotypes and innervation that are similar to those found in the undamaged ear, but little is known about the signaling pathways that guide hair cell differentiation during the regenerative process. The aim of the present study was to examine the factors that specify the orientation of hair cell stereocilia bundles during regeneration. Using organ cultures of the chick utricle, we show that hair cells are properly oriented after having regenerated entirely in vitro and that orientation is not affected by surgical removal of the striolar reversal zone. These results suggest that the orientation of regenerating stereocilia is not guided by the release of a diffusible morphogen from the striolar reversal zone but is specified locally within the regenerating sensory organ. In order to determine the nature of the reorientation cues, we examined the expression patterns of the core planar cell polarity molecule Vangl2 in the normal and regenerating utricle. We found that Vangl2 is asymmetrically expressed on cells within the sensory epithelium and that this expression pattern is maintained after ototoxic injury and throughout regeneration. Notably, treatment with a small molecule inhibitor of c-Jun-N-terminal kinase disrupted the orientation of regenerated hair cells. Both of these results are consistent with the hypothesis that noncanonical Wnt signaling guides hair cell orientation during regeneration.

Laterality and unilateral deafness: Patients with congenital right ear deafness do not develop atypical language dominance.

PubMed

Van der Haegen, Lise; Acke, Frederic; Vingerhoets, Guy; Dhooge, Ingeborg; De Leenheer, Els; Cai, Qing; Brysbaert, Marc

2016-12-01

Auditory speech perception, speech production and reading lateralize to the left hemisphere in the majority of healthy right-handers. In this study, we investigated to what extent sensory input underlies the side of language dominance. We measured the lateralization of the three core subprocesses of language in patients who had profound hearing loss in the right ear from birth and in matched control subjects. They took part in a semantic decision listening task involving speech and sound stimuli (auditory perception), a word generation task (speech production) and a passive reading task (reading). The results show that a lack of sensory auditory input on the right side, which is strongly connected to the contralateral left hemisphere, does not lead to atypical lateralization of speech perception. Speech production and reading were also typically left lateralized in all but one patient, contradicting previous small scale studies. Other factors such as genetic constraints presumably overrule the role of sensory input in the development of (a)typical language lateralization. Copyright © 2015 Elsevier Ltd. All rights reserved.

Structure and function of the mammalian middle ear. I: Large middle ears in small desert mammals.

PubMed

Mason, Matthew J

2016-02-01

Many species of small desert mammals are known to have expanded auditory bullae. The ears of gerbils and heteromyids have been well described, but much less is known about the middle ear anatomy of other desert mammals. In this study, the middle ears of three gerbils (Meriones, Desmodillus and Gerbillurus), two jerboas (Jaculus) and two sengis (elephant-shrews: Macroscelides and Elephantulus) were examined and compared, using micro-computed tomography and light microscopy. Middle ear cavity expansion has occurred in members of all three groups, apparently in association with an essentially 'freely mobile' ossicular morphology and the development of bony tubes for the middle ear arteries. Cavity expansion can occur in different ways, resulting in different subcavity patterns even between different species of gerbils. Having enlarged middle ear cavities aids low-frequency audition, and several adaptive advantages of low-frequency hearing to small desert mammals have been proposed. However, while Macroscelides was found here to have middle ear cavities so large that together they exceed brain volume, the bullae of Elephantulus are considerably smaller. Why middle ear cavities are enlarged in some desert species but not others remains unclear, but it may relate to microhabitat. © 2015 Anatomical Society.

On the role of the central nervous system in regulating the mineralisation of inner-ear otoliths of fish.

PubMed

Anken, Ralf H

2006-12-01

Stato- or otoliths are calcified structures in the organ of balance and equilibrium of vertebrates, the inner ear, where they enhance its sensitivity to gravity. The compact otoliths of fish are composed of the calcium carbonate polymorph aragonite and a small fraction of organic molecules. The latter form a protein skeleton which determines the morphology of an otolith as well as its crystal lattice structure. This short review addresses findings according to which the brain obviously plays a prominent role in regulating the mineralisation of fish otoliths and depends on the gravity vector. Overall, otolith mineralisation has thus been identified to be a unique, neuronally guided biomineralisation process. The following is a hypothetical model for regulation of calcification by efferent vestibular neurons: (1) release of calcium at tight junctions in the macular epithelia, (2) macular carbonic anhydrase activity (which in turn is responsible for carbonate deposition), (3) chemical composition of matrix proteins. The rationale and evidence that support this model are discussed.

[Effect size on resonance of the outer ear canal by simulation of middle ear lesions using a temporal bone preparation].

PubMed

Scheinpflug, L; Vorwerk, U; Begall, K

1995-01-01

By means of a model of the external and the middle ear it is possible to simulate various, exactly defined pathological conditions of the middle ear and to describe their influence on ear canal resonance. Starting point of the investigations are fresh postmortem preparations of 8 human temporal bones with an intact ear drum and a retained skin of the ear canal. The compliance of the middle ear does not significantly differ from the clinical data of probands with healthy ears. After antrotomy it is possible to simulate pathological conditions of the middle ear one after the other at the same temporal bone. The influence of the changed middle ear conditions on ear drum compliance, ear canal volume and on the resonance curve of the external ear canal was investigated. For example, the middle ear was filled with water to create approximately the same conditions as in acute serous otitis media. In this middle ear condition a significant increase of the sound pressure amplification was found, on an average by 4 decibels compared to the unchanged temporal bone model. A small increase in resonance frequency was also measured. The advantages of this model are the approximately physiological conditions and the constant dimensions of the external and middle ear.

Surgical correction of cauliflower ear.

PubMed

Yotsuyanagi, T; Yamashita, K; Urushidate, S; Yokoi, K; Sawada, Y; Miyazaki, S

2002-07-01

We have classified the cauliflower ear into different types according to the zone and the degree of deformity. One major group is deformity without change in the outline of the ear, and this is divided into four subgroups according to the zone. All of these subgroups can be treated by shaving the deformed cartilage through suitable incision lines. For deformities accompanied by a skin deficit, a postauricular skin flap should be used. The other major group is deformity accompanied by a change in the outline of the ear, which is divided into two subgroups. If the ear is rigid, a conchal cartilage graft is used. If the structural integrity of the ear is poor, costal cartilage is used to provide rigidity.

Sensory conflict in motion sickness: An observer theory approach

NASA Technical Reports Server (NTRS)

Oman, Charles M.

1989-01-01

Motion sickness is the general term describing a group of common nausea syndromes originally attributed to motion-induced cerebral ischemia, stimulation of abdominal organ afferent, or overstimulation of the vestibular organs of the inner ear. Sea-, car-, and airsicknesses are the most commonly experienced examples. However, the discovery of other variants such as Cinerama-, flight simulator-, spectacle-, and space sickness in which the physical motion of the head and body is normal or absent has led to a succession of sensory conflict theories which offer a more comprehensive etiologic perspective. Implicit in the conflict theory is the hypothesis that neutral and/or humoral signals originate in regions of the brain subversing spatial orientation, and that these signals somehow traverse to other centers mediating sickness symptoms. Unfortunately, the present understanding of the neurophysiological basis of motion sickness is far from complete. No sensory conflict neuron or process has yet been physiologically identified. To what extent can the existing theory be reconciled with current knowledge of the physiology and pharmacology of nausea and vomiting. The stimuli which causes sickness, synthesizes a contemporary Observer Theory view of the Sensory Conflict hypothesis are reviewed, and a revised model for the dynamic coupling between the putative conflict signals and nausea magnitude estimates is presented. The use of quantitative models for sensory conflict offers a possible new approach to improving the design of visual and motion systems for flight simulators and other virtual environment display systems.

Differential regulation of Hes/Hey genes during inner ear development.

PubMed

Petrovic, Jelena; Gálvez, Hector; Neves, Joana; Abelló, Gina; Giraldez, Fernando

2015-07-01

Notch signaling plays a crucial role during inner ear development and regeneration. Hes/Hey genes encode for bHLH transcription factors identified as Notch targets. We have studied the expression and regulation of Hes/Hey genes during inner ear development in the chicken embryo. Among several Hes/Hey genes examined, only Hey1 and Hes5 map to the sensory regions, although with salient differences. Hey1 expression follows Jag1 expression except at early prosensory stages while Hes5 expression corresponds well to Dl1 expression throughout otic development. Although Hey1 and Hes5 are direct Notch downstream targets, they differ in the level of Notch required for activation. Moreover, they also differ in mRNA stability, showing different temporal decays after Notch blockade. In addition, Bmp, Wnt and Fgf pathways also modify Hey1 and Hes5 expression in the inner ear. Particularly, the Wnt pathway modulates Hey1 and Jag1 expression. Finally, gain of function experiments show that Hey1 and Hes5 cross-regulate each other in a complex manner. Both Hey1 and Hes5 repress Dl1 and Hes5 expression, suggesting that they prevent the transition to differentiation stages, probably by preventing Atoh1 expression. In spite of its association with Jag1, Hey1 does not seem to be instrumental for lateral induction as it does not promote Jag1 expression. We suggest that, besides being both targets of Notch, Hey1 and Hes5 are subject to a rather complex regulation that includes the stability of their transcripts, cross regulation and other signaling pathways. © 2014 Wiley Periodicals, Inc.

Identification of a basic protein of Mr 75,000 as an accessory desmosomal plaque protein in stratified and complex epithelia.

PubMed

Kapprell, H P; Owaribe, K; Franke, W W

1988-05-01

Desmosomes are intercellular adhering junctions characterized by a special structure and certain obligatory constituent proteins such as the cytoplasmic protein, desmoglein. Desmosomal fractions from bovine muzzle epidermis contain, in addition, a major polypeptide of Mr approximately 75,000 ("band 6 protein") which differs from all other desmosomal proteins so far identified by its positive charge (isoelectric at pH approximately 8.5 in the denatured state) and its avidity to bind certain type I cytokeratins under stringent conditions. We purified this protein from bovine muzzle epidermis and raised antibodies to it. Using affinity-purified antibodies, we identified a protein of identical SDS-PAGE mobility and isoelectric pH in all epithelia of higher complexity, including representatives of stratified, complex (pseudostratified) and transitional epithelia as well as benign and malignant human tumors derived from such epithelia. Immunolocalization studies revealed the location of this protein along cell boundaries in stratified and complex epithelia, often resolved into punctate arrays. In some epithelia it seemed to be restricted to certain cell types and layers; in rat cornea, for example, it was only detected in upper strata. Electron microscopic immunolocalization showed that this protein is a component of the desmosomal plaque. However, it was not found in the desmosomes of all simple epithelia examined, in the tumors and cultured cells derived thereof, in myocardiac and Purkinje fiber cells, in arachnoideal cells and meningiomas, and in dendritic reticulum cells of lymphoid tissue, i.e., all cells containing typical desmosomes. The protein was also absent in all nondesmosomal adhering junctions. From these results we conclude that this basic protein is not an obligatory desmosomal plaque constituent but an accessory component specific to the desmosomes of certain kinds of epithelial cells with stratified tissue architecture. This suggests that the Mr 75

Ear Infections and Language Development.

ERIC Educational Resources Information Center

Roberts, Joanne E.; Zeisel, Susan A.

Ear infections in infants and preschoolers can cause mild or moderate temporary hearing loss, which may in turn affect a child's ability to understand and learn language. Noting that providing children with proper medical treatment for ear infections or middle ear fluid is important in preventing possible problems with language development, this…

Clinical application of neurotrophic factors: the potential for primary auditory neuron protection

PubMed Central

Gillespie, Lisa N.; Shepherd, Robert K.

2007-01-01

Sensorineural hearing loss, as a result of damage to or destruction of the sensory epithelia within the cochlea, is a common cause of deafness. The subsequent degeneration of the neural elements within the inner ear may impinge upon the efficacy of the cochlear implant. Experimental studies have demonstrated that neurotrophic factors can prevent this degeneration in animal models of deafness, and can even provide functional benefits. Neurotrophic factor therapy may, therefore, provide similar protective effects in humans, resulting in improved speech perception outcomes among cochlear implant patients. There are, however, numerous issues pertaining to delivery techniques and treatment regimes which need to be addressed prior to any clinical application. This review considers these issues in view of the potential therapeutic application of neurotrophic factors within the auditory system. PMID:16262651

Hearing after congenital deafness: central auditory plasticity and sensory deprivation.

PubMed

Kral, A; Hartmann, R; Tillein, J; Heid, S; Klinke, R

2002-08-01

The congenitally deaf cat suffers from a degeneration of the inner ear. The organ of Corti bears no hair cells, yet the auditory afferents are preserved. Since these animals have no auditory experience, they were used as a model for congenital deafness. Kittens were equipped with a cochlear implant at different ages and electro-stimulated over a period of 2.0-5.5 months using a monopolar single-channel compressed analogue stimulation strategy (VIENNA-type signal processor). Following a period of auditory experience, we investigated cortical field potentials in response to electrical biphasic pulses applied by means of the cochlear implant. In comparison to naive unstimulated deaf cats and normal hearing cats, the chronically stimulated animals showed larger cortical regions producing middle-latency responses at or above 300 microV amplitude at the contralateral as well as the ipsilateral auditory cortex. The cortex ipsilateral to the chronically stimulated ear did not show any signs of reduced responsiveness when stimulating the 'untrained' ear through a second cochlear implant inserted in the final experiment. With comparable duration of auditory training, the activated cortical area was substantially smaller if implantation had been performed at an older age of 5-6 months. The data emphasize that young sensory systems in cats have a higher capacity for plasticity than older ones and that there is a sensitive period for the cat's auditory system.

Swimmer's Ear (External Otitis)

MedlinePlus

... t help, your doctor might prescribe a stronger pain reliever. You'll use this only for a short time — until the ear drops and antibiotics begin to work. To protect your ear while it heals, your ...

Ear molding in newborn infants with auricular deformities.

PubMed

Byrd, H Steve; Langevin, Claude-Jean; Ghidoni, Lorraine A

2010-10-01

A review of a single physician's experience in managing over 831 infant ear deformities (488 patients) is presented. The authors' methods of molding have advanced from the use of various tapes, glues, and stents, to a comprehensive yet simple system that shapes the antihelix, the triangular fossa, the helical rim, and the overly prominent conchal-mastoid angle (EarWell Infant Ear Correction System). The types of deformities managed, and their relative occurrence, are as follows: (1) prominent/cup ear, 373 ears (45 percent); (2) lidding/lop ear, 224 ears (27 percent); (3) mixed ear deformities, 83 ears (10 percent) (all had associated conchal crus); (4) Stahl's ear, 66 ears (8 percent); (5) helical rim abnormalities, 58 ears (7 percent); (6) conchal crus, 25 ears (3 percent); and (7) cryptotia, two ears (0.2 percent). Bilateral deformities were present in 340 patients (70 percent), with unilateral deformities in 148 patients (30 percent). Fifty-eight infant ears (34 patients) were treated using the final version of the EarWell Infant Ear Correction System with a success rate exceeding 90 percent (good to excellent results). The system was found to be most successful when begun in the first week of the infant's life. When molding was initiated after 3 weeks from birth, only approximately half of the infants had a good response. Congenital ear deformities are common and only approximately 30 percent self-correct. These deformities can be corrected by initiating appropriate molding in the first week of life. Neonatal molding reduces the need for surgical correction with results that often exceed what can be achieved with the surgical alternative.

Wnt signaling induces proliferation of sensory precursors in the postnatal mouse cochlea.

PubMed

Chai, Renjie; Kuo, Bryan; Wang, Tian; Liaw, Eric J; Xia, Anping; Jan, Taha A; Liu, Zhiyong; Taketo, Makoto M; Oghalai, John S; Nusse, Roeland; Zuo, Jian; Cheng, Alan G

2012-05-22

Inner ear hair cells are specialized sensory cells essential for auditory function. Previous studies have shown that the sensory epithelium is postmitotic, but it harbors cells that can behave as progenitor cells in vitro, including the ability to form new hair cells. Lgr5, a Wnt target gene, marks distinct supporting cell types in the neonatal cochlea. Here, we tested the hypothesis that Lgr5(+) cells are Wnt-responsive sensory precursor cells. In contrast to their quiescent in vivo behavior, Lgr5(+) cells isolated by flow cytometry from neonatal Lgr5(EGFP-CreERT2/+) mice proliferated and formed clonal colonies. After 10 d in culture, new sensory cells formed and displayed specific hair cell markers (myo7a, calretinin, parvalbumin, myo6) and stereocilia-like structures expressing F-actin and espin. In comparison with other supporting cells, Lgr5(+) cells were enriched precursors to myo7a(+) cells, most of which formed without mitotic division. Treatment with Wnt agonists increased proliferation and colony-formation capacity. Conversely, small-molecule inhibitors of Wnt signaling suppressed proliferation without compromising the myo7a(+) cells formed by direct differentiation. In vivo lineage tracing supported the idea that Lgr5(+) cells give rise to myo7a(+) hair cells in the neonatal Lgr5(EGFP-CreERT2/+) cochlea. In addition, overexpression of β-catenin initiated proliferation and led to transient expansion of Lgr5(+) cells within the cochlear sensory epithelium. These results suggest that Lgr5 marks sensory precursors and that Wnt signaling can promote their proliferation and provide mechanistic insights into Wnt-responsive progenitor cells during sensory organ development.

[The effect of OSAHS on middle ear and inner ear vestibule function advances].

PubMed

Li, K L; Li, J R

2016-05-20

Obstructive sleep apnea hypopnea syndrome(OSAHS) as a common frequentlyoccurring disease, it can cause repeated episodes of hypoxaemia and hypercapnia during sleep. With long period of hypoxaemia, obvious pathological changes and dysfunction emerged in heart，brain and lung then all kinds of clinical symptoms appear. Because of the middle ear and inner ear themselves anatomical characteristics and blood supply of regulating mechanism， they often has been damaged before the other important organ damage. As scholars have indepth study of the auditory system complications in patients with OSAHS, various influence of OSAHS on the middle ear，inner ear also gradually be known.This paper will review the effect of OSAHS on middle ear， inner ear and vestibule function, hope to have some application value for clinical work. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

The cytokine macrophage migration inhibitory factor (MIF) acts as a neurotrophin in the developing inner ear of the zebrafish, Danio rerio

PubMed Central

Shen, Yu-chi; Thompson, Deborah L.; Kuah, Meng-Kiat; Wong, Kah-Loon; Wu, Karen L.; Linn, Stephanie A.; Jewett, Ethan M.; Shu-Chien, Alexander Chong; Barald, Kate F.

2012-01-01

Macrophage migration inhibitory factor (MIF) plays versatile roles in the immune system. MIF is also widely expressed during embryonic development, particularly in the nervous system, although its roles in neural development are only beginning to be understood. Evidence from frogs, mice and zebrafish suggests that MIF has a major role as a neurotrophin in the early development of sensory systems, including the auditory system. Here we show that the zebrafish mif pathway is required for both sensory hair cell (HC) and sensory neuronal cell survival in the ear, for HC differentiation, semicircular canal formation, statoacoustic ganglion (SAG) development, and lateral line HC differentiation. This is consistent with our findings that MIF is expressed in the developing mammalian and avian auditory systems and promotes mouse and chick SAG neurite outgrowth and neuronal survival, demonstrating key instructional roles for MIF in vertebrate otic development. PMID:22210003

Listening to the ear

NASA Astrophysics Data System (ADS)

Shera, Christopher A.

Otoacoustic emissions demonstrate that the ear creates sound while listening to sound, offering a promising acoustic window on the mechanics of hearing in awake, listening human beings. That window is clouded, however, by an incomplete knowledge of wave reflection and transmission, both forth and back within the cochlea and through the middle ear. This thesis "does windows," addressing wave propagation and scattering on both sides of the middle ear. A summary of highlights follows. Measurements of the cochlear input impedance in cat are used to identify a new symmetry in cochlear mechanics-termed "tapering symmetry" after its geometric interpretation in simple models-that guarantees that the wavelength of the traveling wave changes slowly with position near the stapes. Waves therefore propagate without reflection through the basal turns of the cochlea. Analytic methods for solving the cochlear wave equations using a perturbative scattering series are given and used to demonstrate that, contrary to common belief, conventional cochlear models exhibit negligible internal reflection whether or not they accurately represent the tapering symmetries of the inner ear. Frameworks for the systematic "deconstruction" of eardrum and middle-ear transduction characteristics are developed and applied to the analysis of noninvasive measurements of middle-ear and cochlear mechanics. A simple phenomenological model of inner-ear compressibility that correctly predicts hearing thresholds in patients with missing or disarticulated middle-ear ossicles is developed and used to establish an upper bound on cochlear compressibility several orders of magnitude smaller than that provided by direct measurements. Accurate measurements of stimulus frequency evoked otoacoustic emissions are performed and used to determine the form and frequency variation of the cochlear traveling-wave ratio noninvasively. Those measurements are inverted to obtain the spatial distribution of mechanical

Listening to the Ear

NASA Astrophysics Data System (ADS)

Shera, Christopher Alan

Otoacoustic emissions demonstrate that the ear creates sound while listening to sound, offering a promising acoustic window on the mechanics of hearing in awake, listening human beings. That window is clouded, however, by an incomplete knowledge of wave reflection and transmission, both forth and back within the cochlea and through the middle ear. This thesis "does windows," addressing wave propagation and scattering on both sides of the middle ear. A summary of highlights follows. Measurements of the cochlear input impedance in cat are used to identify a new symmetry in cochlear mechanics--termed "tapering symmetry" after its geometric interpretation in simple models--that guarantees that the wavelength of the traveling wave changes slowly with position near the stapes. Waves therefore propagate without reflection through the basal turns of the cochlea. Analytic methods for solving the cochlear wave equations using a perturbative scattering series are given and used to demonstrate that, contrary to common belief, conventional cochlear models exhibit negligible internal reflection whether or not they accurately represent the tapering symmetries of the inner ear. Frameworks for the systematic "deconstruction" of eardrum and middle-ear transduction characteristics are developed and applied to the analysis of noninvasive measurements of middle-ear and cochlear mechanics. A simple phenomenological model of inner-ear compressibility that correctly predicts hearing thresholds in patients with missing or disarticulated middle-ear ossicles is developed and used to establish an upper bound on cochlear compressibility several orders of magnitude smaller than that provided by direct measurements. Accurate measurements of stimulus -frequency evoked otoacoustic emissions are performed and used to determine the form and frequency variation of the cochlear traveling-wave ratio noninvasively. Those measurements are inverted to obtain the spatial distribution of mechanical

A morphometric study of the human ear.

PubMed

Alexander, K Skaria; Stott, David J; Sivakumar, Branavan; Kang, Norbert

2011-01-01

We examined variations in the shape of the human ear according to age, sex and ethnic group with particular attention to ear prominence. 420 volunteers were recruited. Measurements included; head height and length, ear height and axis, antihelix taken off angle, earlobe length and width, ear width at the helical root and tragus. Prominence was measured at the helical root and tragus (conchomastoid angle, conchal bowl depth and helical-mastoid distance). Good symmetry was shown for all measurements. Ethnically Indian volunteers had the largest ears (both length and width), followed by Caucasians, and Afro-Caribbeans. This trend was significant in males (p<0.001), but not significant in females (p=0.087). Ears increased in size throughout life. Subjectively, only 2% of volunteers felt their ears were prominent compared to 10% in the opinion of the principal investigator. No objective measurements were identified that accurately predicted subjective perceptions of prominence. We found consistent trends in ear morphology depending on ethnic group, age and sex. Our study was unable to define an objective method for assessing ear prominence. Decisions about what constitutes a prominent ear should be left to personal and aesthetic choice. Copyright © 2010 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Listening to Nature's orchestra with peculiar ears

NASA Astrophysics Data System (ADS)

Yager, David D.

2003-04-01

Insects use hearing for the crucial tasks of communicating with conspecifics and avoiding predators. Although all are based on the same acoustic principles, the diversity of insect ears is staggering and instructive. For instance, a South African grasshopper demonstrates that hearing conspecific calls is possible over distances 1 km with ears that do not have tympana. Actually, these creatures have six pairs of ears that play different roles in behavior. In numerical contrast, praying mantises have just a single ear in the ventral midline. The ear is very effective at detecting ultrasonic bat cries. However, the bioacoustics of sound transduction by two tympana facing each other in a deep, narrow slit is a puzzle. Tachinid flies demonstrate that directional hearing at 5 kHz is possible with a pair of ears fused together to give a total size of 1 mm. The ears are under the fly's chin. Hawk moths have their ears built into their mouthparts and the tympanum is more like a hollow ball than the usual membrane. As an apt last example, cicada ears are actually part of the orchestra: their tympana function both in sound reception and sound production.

Unclassified congenital deformities of the external ear.

PubMed

Vathulya, Madhubari

2018-01-01

Congenital ear deformities are a common entity. They are found in isolation or as a part of syndrome in patients. They may involve the external, middle or inner ear or in any of these combinations. Three patients of different ages presented with deformities including mirror image duplication of the superior auricle, unclassified deformities of ear lobule (wavy lobule) and deformity of superior auricle with unclassified variety of lateral ear pit. This article highlights that there are further cases of ear deformities that are noticed in the general population who come for cosmetic correction, and hence, there is a need for further modifying the classification of ear deformities.

Ultrasound characterization of middle ear effusion.

PubMed

Seth, Rahul; Discolo, Christopher M; Palczewska, Grazyna M; Lewandowski, Jan J; Krakovitz, Paul R

2013-01-01

To further enhance and assess the ability to characterize middle ear effusion (MEE) using non-invasive ultrasound technology. This is a prospective unblinded comparison study. Fifty-six children between the ages of 6 months and 17 years scheduled to undergo bilateral myringotomy with pressure equalization tube placement were enrolled. With the child anesthetized, the probe was placed into the external ear canal after sterile water was inserted. Ultrasound recordings of middle ear contents were analyzed by computer algorithm. Middle ear fluid was collected during myringotomy and analyzed for bacterial culture and viscosity. Ultrasound waveforms yielded a computer algorithm interpretation of middle ear contents in 66% of ears tested. When a result was obtained, the sensitivity and specificity for successfully characterizing middle ear fluid content as either void of fluid, thick fluid (mucoid), or thin fluid (serous or purulent) were at least 94%. Mucoid effusions had higher measured viscosity values (P=.002). Viscosity measures were compared to culture result, and those with low viscosity (thin consistency) had a higher likelihood of having a positive culture (P=.048). The device sensitivity and specificity for fluid detection were 94% or greater among interpretable waveforms (66% of those tested). Although this technology provides important information of the middle ear effusion presence and characteristic, further technological improvements are needed. Copyright © 2013 Elsevier Inc. All rights reserved.

Ultrasound Characterization of Middle Ear Effusion

PubMed Central

Seth, Rahul; Discolo, Christopher M; Palczewska, Grazyna M; Lewandowski, Jan J; Krakovitz, Paul R

2012-01-01

Purpose To further enhance and assess the ability to characterize middle ear effusion (MEE) using non-invasive ultrasound technology. Materials and Methods This is a prospective unblinded comparison study. Fifty-six children between the ages of 6 months and 17 years scheduled to undergo bilateral myringotomy with pressure equalization tube placement were enrolled. With the child anesthetized, the probe was placed into the external ear canal after sterile water was inserted. Ultrasound recordings of middle ear contents were analyzed by computer algorithm. Middle ear fluid was collected during myringotomy and analyzed for bacterial culture and viscosity. Results Ultrasound waveforms yielded a computer algorithm interpretation of middle ear contents in 66% of ears tested. When a result was obtained, the sensitivity and specificity for successfully characterizing middle ear fluid content as either void of fluid, thick fluid (mucoid), or thin fluid (serous or purulent) was at least 94%. Mucoid effusions had higher measured viscosity values (P=0.002). Viscosity measures were compared to culture result, and those with low viscosity (thin consistency) had a higher likelihood of having a positive culture (P=0.048). Conclusion The device sensitivity and specificity for fluid detection was 94% or greater among interpretable waveforms (66% of those tested). Although this technology provides important information of the middle ear effusion presence and characteristic, further technological improvements are needed. PMID:23084430

sox2 and sox3 Play unique roles in development of hair cells and neurons in the zebrafish inner ear.

PubMed

Gou, Yunzi; Vemaraju, Shruti; Sweet, Elly M; Kwon, Hye-Joo; Riley, Bruce B

2018-03-01

Formation of neural and sensory progenitors in the inner ear requires Sox2 in mammals, and in other species is thought to rely on both Sox2 and Sox3. How Sox2 and/or Sox3 promote different fates is poorly understood. Our mutant analysis in zebrafish showed that sox2 is uniquely required for sensory development while sox3 is uniquely required for neurogenesis. Moderate misexpression of sox2 during placodal stages led to development of otic vesicles with expanded sensory and reduced neurogenic domains. However, high-level misexpression of sox2 or sox3 expanded both sensory and neurogenic domains to fill the medial and lateral halves of the otic vesicle, respectively. Disruption of medial factor pax2a eliminated the ability of sox2/3 misexpression to expand sensory but not neurogenic domains. Additionally, mild misexpression of fgf8 during placodal development was sufficient to specifically expand the zone of prosensory competence. Later, cross-repression between atoh1a and neurog1 helps maintain the sensory-neural boundary, but unlike mouse this does not require Notch activity. Together, these data show that sox2 and sox3 exhibit intrinsic differences in promoting sensory vs. neural competence, but at high levels these factors can mimic each other to enhance both states. Regional cofactors like pax2a and fgf8 also modify sox2/3 functions. Copyright © 2018 Elsevier Inc. All rights reserved.

Functional Roles of Bestrophins in Ocular Epithelia

PubMed Central

Marmorstein, Alan D.; Cross, Harold E.; Peachey, Neal S.

2009-01-01

There are four members of the bestrophin family of proteins in the human genome, of which two are known to be expressed in the eye. The gene BEST1 (formerly VMD2) which encodes the protein bestrophin-1 (Best1) was first identified in 1998. Mutations in this gene have now been associated with four clinically distinguishable human eye diseases, collectively referred to as “bestrophinopathies”. Over the last decade, laboratories have sought to understand how Best1 mutations could result in eye diseases that range in presentation from macular degeneration to nanophthalmos. The majority of our knowledge comes from studies that have sought to understand how Best1 mutations or dysfunction could induce the classical symptoms of the most common of these diseases: Best vitelliform macular dystrophy (BVMD). BVMD is a dominant trait that is characterized electrophysiologically by a diminished electrooculogram light peak with a normal clinical electroretinogram. This together with the localization of Best1 to the retinal pigment epithelium (RPE) basolateral plasma membrane and data from heterologous expression studies, have led to the proposal that Best1 generates the light peak, and that bestrophins are a family of Ca2+ activated Cl- channels (CaCCs). However, data from Best1 knock-out and knock-in mice, coupled with the recent discovery of a recessive bestrophinopathy suggest that Best1 does not generate the light peak. Recently Best2 was found to be expressed in non-pigmented epithelia in the ciliary body. However, aqueous dynamics in Best2 knock-out mice do not support a role for Best2 as a Cl- channel. Thus, the purported CaCC function of the bestrophins and how loss of this function relates to clinical disease needs to be reassessed. In this article, we examine data obtained from tissue-type and animal models and discuss the current state of bestrophin research, what roles Best1 and Best2 may play in ocular epithelia and ocular electrophysiology, and how perturbation

Inner ear development: building a spiral ganglion and an organ of Corti out of unspecified ectoderm.

PubMed

Fritzsch, Bernd; Pan, Ning; Jahan, Israt; Elliott, Karen L

2015-07-01

The mammalian inner ear develops from a placodal thickening into a complex labyrinth of ducts with five sensory organs specialized to detect position and movement in space. The mammalian ear also develops a spiraled cochlear duct containing the auditory organ, the organ of Corti (OC), specialized to translate sound into hearing. Development of the OC from a uniform sheet of ectoderm requires unparalleled precision in the topological developmental engineering of four different general cell types, namely sensory neurons, hair cells, supporting cells, and general otic epithelium, into a mosaic of ten distinctly recognizable cell types in and around the OC, each with a unique distribution. Moreover, the OC receives unique innervation by ear-derived spiral ganglion afferents and brainstem-derived motor neurons as efferents and requires neural-crest-derived Schwann cells to form myelin and neural-crest-derived cells to induce the stria vascularis. This transformation of a sheet of cells into a complicated interdigitating set of cells necessitates the orchestrated expression of multiple transcription factors that enable the cellular transformation from ectoderm into neurosensory cells forming the spiral ganglion neurons (SGNs), while simultaneously transforming the flat epithelium into a tube, the cochlear duct, housing the OC. In addition to the cellular and conformational changes forming the cochlear duct with the OC, changes in the surrounding periotic mesenchyme form passageways for sound to stimulate the OC. We review molecular developmental data, generated predominantly in mice, in order to integrate the well-described expression changes of transcription factors and their actions, as revealed in mutants, in the formation of SGNs and OC in the correct position and orientation with suitable innervation. Understanding the molecular basis of these developmental changes leading to the formation of the mammalian OC and highlighting the gaps in our knowledge might guide in

Inner ear development: Building a spiral ganglion and an organ of Corti out of unspecified ectoderm

PubMed Central

Fritzsch, Bernd; Pan, Ning; Jahan, Israt; Elliott, Karen L.

2014-01-01

The mammalian inner ear develops from a placodal thickening into a complex labyrinth of ducts with five sensory organs specialized to detect position and movement in space. In addition, the mammalian ear develops a spiraled cochlear duct containing the auditory organ, the organ of Corti (OC), specialized to translate sound into hearing. Developing the OC out of a uniform sheet of ectoderm requires an unparalleled precision in topological developmental engineering of four different general cell types, sensory neurons, hair cells, supporting cells, and general otic epithelium, into a mosaic of ten distinctly recognizable cell types in and around the OC, each with a unique distribution. In addition, the OC receives a unique innervation by ear-derived spiral ganglion afferents and brainstem-derived motor neurons as efferents, and requires neural crest-derived Schwann cells to form myelin and neural crest-derived cells to induce the stria vascularis. To achieve this transformation of a sheet of cells into a complicated interdigitating set of cells necessitates the orchestrated expression of multiple transcription factors that enable the cellular transformation from ectoderm into neurosensory cells forming the spiral ganglion neurons (SGN) while simultaneously transforming the flat epithelium into a tube, the cochlear duct housing the OC. In addition to the cellular and conformational changes to make the cochlear duct with the OC, additional changes in the surrounding periotic mesenchyme form passageways for sound to stimulate the OC. This article reviews molecular developmental data generated predominantly in mice. The available data are ordered into a plausible scenario that integrates the well described expression changes of transcription factors and their actions revealed in mouse mutants for formation of SGNs and OC in the right position and orientation with the right kind of innervation. Understanding the molecular basis of these developmental changes leading to

Age-Related Sensory Impairments and Risk of Cognitive Impairment

PubMed Central

Fischer, Mary E; Cruickshanks, Karen J.; Schubert, Carla R; Pinto, Alex A; Carlsson, Cynthia M; Klein, Barbara EK; Klein, Ronald; Tweed, Ted S.

2016-01-01

Background/Objectives To evaluate the associations of sensory impairments with the 10-year risk of cognitive impairment. Previous work has primarily focused on the relationship between a single sensory system and cognition. Design The Epidemiology of Hearing Loss Study (EHLS) is a longitudinal, population-based study of aging in the Beaver Dam, WI community. Baseline examinations were conducted in 1993 and follow-up exams have been conducted every 5 years. Setting General community Participants EHLS members without cognitive impairment at EHLS-2 (1998–2000). There were 1,884 participants (mean age = 66.7 years) with complete EHLS-2 sensory data and follow-up information. Measurements Cognitive impairment was a Mini-Mental State Examination score of < 24 or history of dementia or Alzheimer’s disease. Hearing impairment was a pure-tone average of hearing thresholds (0.5, 1, 2 and 4 kHz) of > 25 decibel Hearing Level in either ear. Visual impairment was Pelli-Robson contrast sensitivity of < 1.55 log units in the better eye and olfactory impairment was a San Diego Odor Identification Test score of < 6. Results Hearing, visual, and olfactory impairment were independently associated with cognitive impairment risk [Hearing: Hazard Ratio (HR) = 1.90, 95% Confidence Interval (C.I.) = 1.11, 3.26; Vision: HR = 2.05, 95% C.I. = 1.24, 3.38; Olfaction: HR = 3.92, 95% C.I. = 2.45, 6.26]. However, 85% with hearing impairment, 81% with visual impairment, and 76% with olfactory impairment did not develop cognitive impairment during follow-up. Conclusion The relationship between sensory impairment and cognitive impairment was not unique to one sensory system suggesting sensorineural health may be a marker of brain aging. The development of a combined sensorineurocognitive measure may be useful in uncovering mechanisms of healthy brain aging. PMID:27611845

Is Attention Shared Between the Ears?1

PubMed Central

Shiffrin, Richard M.; Pisoni, David B.; Castaneda-Mendez, Kicab

2012-01-01

This study tests the locus of attention during selective listening for speech-like stimuli. Can processing be differentially allocated to the two ears? Two conditions were used. The simultaneous condition involved one of four randomly chosen stop-consonants being presented to one of the ears chosen at random. The sequential condition involved two intervals; in the first S listened to the right ear; in the second S listened to the left ear. One of the four consonants was presented to an attended ear during one of these intervals. Experiment I used no distracting stimuli. Experiment II utilized a distracting consonant not confusable with any of the four target consonants. This distractor was always presented to any ear not containing a target. In both experiments, simultaneous and sequential performance were essentially identical, despite the need for attention sharing between the two ears during the simultaneous condition. We conclude that selective attention does not occur during perceptual processing of speech sounds presented to the two ears. We suggest that attentive effects arise in short-term memory following processing. PMID:23226838

21 CFR 870.2710 - Ear oximeter.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear oximeter. 870.2710 Section 870.2710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2710 Ear oximeter. (a) Identification. An ear...

Can Loud Music Hurt My Ears?

MedlinePlus

... Videos for Educators Search English Español Can Loud Music Hurt My Ears? KidsHealth / For Kids / Can Loud Music Hurt My Ears? Print en español La música ... up? Oh! You want to know if loud music can hurt your ears . Are you asking because ...

21 CFR 870.2710 - Ear oximeter.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear oximeter. 870.2710 Section 870.2710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2710 Ear oximeter. (a) Identification. An ear...

Dimethyl sulfoxide (DMSO) exacerbates cisplatin-induced sensory hair cell death in zebrafish (Danio rerio).

PubMed

Uribe, Phillip M; Mueller, Melissa A; Gleichman, Julia S; Kramer, Matthew D; Wang, Qi; Sibrian-Vazquez, Martha; Strongin, Robert M; Steyger, Peter S; Cotanche, Douglas A; Matsui, Jonathan I

2013-01-01

Inner ear sensory hair cells die following exposure to aminoglycoside antibiotics or chemotherapeutics like cisplatin, leading to permanent auditory and/or balance deficits in humans. Zebrafish (Danio rerio) are used to study drug-induced sensory hair cell death since their hair cells are similar in structure and function to those found in humans. We developed a cisplatin dose-response curve using a transgenic line of zebrafish that expresses membrane-targeted green fluorescent protein under the control of the Brn3c promoter/enhancer. Recently, several small molecule screens have been conducted using zebrafish to identify potential pharmacological agents that could be used to protect sensory hair cells in the presence of ototoxic drugs. Dimethyl sulfoxide (DMSO) is typically used as a solvent for many pharmacological agents in sensory hair cell cytotoxicity assays. Serendipitously, we found that DMSO potentiated the effects of cisplatin and killed more sensory hair cells than treatment with cisplatin alone. Yet, DMSO alone did not kill hair cells. We did not observe the synergistic effects of DMSO with the ototoxic aminoglycoside antibiotic neomycin. Cisplatin treatment with other commonly used organic solvents (i.e. ethanol, methanol, and polyethylene glycol 400) also did not result in increased cell death compared to cisplatin treatment alone. Thus, caution should be exercised when interpreting data generated from small molecule screens since many compounds are dissolved in DMSO.

Dimethyl Sulfoxide (DMSO) Exacerbates Cisplatin-induced Sensory Hair Cell Death in Zebrafish (Danio rerio)

PubMed Central

Gleichman, Julia S.; Kramer, Matthew D.; Wang, Qi; Sibrian-Vazquez, Martha; Strongin, Robert M.; Steyger, Peter S.; Cotanche, Douglas A.; Matsui, Jonathan I.

2013-01-01

Inner ear sensory hair cells die following exposure to aminoglycoside antibiotics or chemotherapeutics like cisplatin, leading to permanent auditory and/or balance deficits in humans. Zebrafish (Danio rerio) are used to study drug-induced sensory hair cell death since their hair cells are similar in structure and function to those found in humans. We developed a cisplatin dose-response curve using a transgenic line of zebrafish that expresses membrane-targeted green fluorescent protein under the control of the Brn3c promoter/enhancer. Recently, several small molecule screens have been conducted using zebrafish to identify potential pharmacological agents that could be used to protect sensory hair cells in the presence of ototoxic drugs. Dimethyl sulfoxide (DMSO) is typically used as a solvent for many pharmacological agents in sensory hair cell cytotoxicity assays. Serendipitously, we found that DMSO potentiated the effects of cisplatin and killed more sensory hair cells than treatment with cisplatin alone. Yet, DMSO alone did not kill hair cells. We did not observe the synergistic effects of DMSO with the ototoxic aminoglycoside antibiotic neomycin. Cisplatin treatment with other commonly used organic solvents (i.e. ethanol, methanol, and polyethylene glycol 400) also did not result in increased cell death compared to cisplatin treatment alone. Thus, caution should be exercised when interpreting data generated from small molecule screens since many compounds are dissolved in DMSO. PMID:23383324

Association Between Sensory Impairment and Dementia in Older Adults: Evidence from China.

PubMed

Luo, Yanan; He, Ping; Guo, Chao; Chen, Gong; Li, Ning; Zheng, Xiaoying

2018-03-01

To determine the association between sensory impairment and dementia in Chinese older adults. Cross-sectional. Older adults in 31 provinces of China. Individuals aged 65 and older (N = 250,752). Psychiatrists ascertained dementia based on the International Classification of Diseases, 10th Revision. Sensory impairment was measured as only hearing impairment, only vision impairment, and combined sensory impairment (combined hearing and vision impairment). Hearing impairment was defined as greater than 40 dB loss in the better ear according to the standard of the World Health Organization (WHO) Prevention of Deafness and Hearing Impairment (PDH) standard 97.3. Ophthalmologists assessed vision impairment according to the WHO best-corrected visual acuity (BCVA) criteria (low vision: 0.05≤BCVA ≤0.29; blindness: no light perception ≤ BCVA <0.05, visual field less than 10 degrees; the better-seeing eye). The prevalence of dementia was 0.41% (95% CI = 0.39-0.44%) without sensory impairment, 0.83% (95% CI = 0.70-0.99%) with only visual impairment, 0.61 (95% CI = 0.53-0.71%) with only hearing impairment, and 1.27% (95% CI = 1.00-1.61%) with combined sensory impairments. After adjusting for sociodemographic characteristics, vision impairment (odds ratio (OR) = 1.58, 95% CI = 1.28-1.96) and combined sensory impairments (OR = 1.64, 95% CI = 1.23-2.20) were associated with greater risk of severe to extremely severe dementia. Hearing impairment was not significantly associated with dementia. Sensory impairments are associated with greater risk of dementia in Chinese older adults. Studies are needed to further explore the pathway of this association in Chinese elderly adults and to provide suggestions to improve health status for this population. © 2018, Copyright the Authors Journal compilation © 2018, The American Geriatrics Society.

Targeted Deletion of Sox10 by Wnt1-cre Defects Neuronal Migration and Projection in the Mouse Inner Ear

PubMed Central

Mao, YanYan; Reiprich, Simone; Wegner, Michael; Fritzsch, Bernd

2014-01-01

Sensory nerves of the brainstem are mostly composed of placode-derived neurons, neural crest-derived neurons and neural crest-derived Schwann cells. This mixed origin of cells has made it difficult to dissect interdependence for fiber guidance. Inner ear-derived neurons are known to connect to the brain after delayed loss of Schwann cells in ErbB2 mutants. However, the ErbB2 mutant related alterations in the ear and the brain compound interpretation of the data. We present here a new model to evaluate exclusively the effect of Schwann cell loss on inner ear innervation. Conditional deletion of the neural crest specific transcription factor, Sox10, using the rhombic lip/neural crest specific Wnt1-cre driver spares Sox10 expression in the ear. We confirm that neural crest-derived cells provide a stop signal for migrating spiral ganglion neurons. In the absence of Schwann cells, spiral ganglion neurons migrate into the center of the cochlea and even out of the ear toward the brain. Spiral ganglion neuron afferent processes reach the organ of Corti, but many afferent fibers bypass the organ of Corti to enter the lateral wall of the cochlea. In contrast to this peripheral disorganization, the central projection to cochlear nuclei is normal. Compared to ErbB2 mutants, conditional Sox10 mutants have limited cell death in spiral ganglion neurons, indicating that the absence of Schwann cells alone contributes little to the embryonic survival of neurons. These data suggest that neural crest-derived cells are dispensable for all central and some peripheral targeting of inner ear neurons. However, Schwann cells provide a stop signal for migratory spiral ganglion neurons and facilitate proper targeting of the organ of Corti by spiral ganglion afferents. PMID:24718611

Immunologic Disorders of the Inner Ear.

ERIC Educational Resources Information Center

Kinney, William C.; Hughes, Gordon B.

1997-01-01

Immune inner ear disease represents a series of immune system mediated problems that can present with hearing loss, dizziness, or both. The etiology, presentation, testing, and treatment of primary immune inner ear disease is discussed. A review of secondary immune inner ear disease is presented for comparison. (Contains references.) (Author/CR)

Vasopressin Receptor Signaling and Cycling of Water Channels in Renal Epithelia

DTIC Science & Technology

1992-08-22

as well as renal model epithelia, including amphibian urinary bladder tissue (Bentley, 1958; DiBona , 1981; Hays, 1983; Mia et al., 1987). The increase...propagation of numerous microvilli on the membrane surface (Davis et al., 1974; DiBona , 1981; Mia et al., 1983, 1988; Mills and Malik, 1978; Spinelli et...fusion events are dependent very likely on the presence of cytosolic microtubules and microfilaments (Taylor et al., 1973; Hardy and DiBona , 1982; Hays

3D Printed Bionic Ears

PubMed Central

Mannoor, Manu S.; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A.; Soboyejo, Winston O.; Verma, Naveen; Gracias, David H.; McAlpine, Michael C.

2013-01-01

The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the precise anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing. PMID:23635097

3D printed bionic ears.

PubMed

Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C

2013-06-12

The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing.

A different type of 'glue ear': report of an unusual case of prominent ears.

PubMed

Purcell, Elizabeth M; O'Neill, Ann C; Regan, Padraic J

2003-09-01

Prominent ears is a condition that can cause extreme psychological distress in young people. This cosmetic deformity can be corrected by otoplasty, an outpatient surgical procedure that is associated with a high rate of patient satisfaction. We report the unusual case of a teenage boy who had repeatedly applied cyanoacrylate adhesive ("superglue") to his postauricular skin in an attempt to pin back his prominent ears. This case of "glue ear" was ultimately resolved by successful otoplasty, although the residual effects of the glue resulted in delayed healing of the surgical wound.

What Is an Ear Infection?

MedlinePlus

... Hearing Loss? Taking Care of Your Ears Swimmer's Ear Perforated Eardrum What's Earwax? View ... All information on KidsHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, ...

[Atypical inflammation of the middle ear].

PubMed

Garov, E V; Kryukov, A I; Zelenkova, V N; Sidorina, N G; Kaloshina, A S

The objective of the present study was to characterize the patients presenting with atypical inflammation of the middle ear and consider the currently available methods for their examination. A total of 20 patients at the age from 16 to 66 years were admitted to the Department of Ear Microsurgery during the period from 2008 and 2016 for the treatment of atypical inflammation of the middle ear. Eleven of them (18 ears) were found to have tuberculous lesions (TL) of the middle ear while the remaining 9 patients (11 ears) suffered giant cell vasculitis (GCV). All the patients underwent the general clinical and otorhinolaryngological examination, computed tomography of the temporal bones and the thoracic cavity organs, cytological, bacteriological, pathomorphological, and molecular-genetic studies including PCR diagnostics, rheumatological tests, as well as counseling by a phthisiotherapist and rheumatologist. The primary localization of TL in the middle ear was documented in 6 patients including its association with lung lesions in 5 cases. The clinical picture of the disease in 5 patients was that of smoldering exudative pathology and in 6 ones was accompanied by suppurative perforative otitis media. According to the laboratory analyses, bacteriological diagnostics proved efficient in 9% of the patients, pathomorphological and cytological diagnostics in 18% and 27.3% of the cases respectively while the effectiveness of PCR diagnostics was estimated at 55%. The diagnosis in individual patients was established within the period from 1 month to 1.5 years after they first sought medical advice in connection with complaints of the ear disease. Tuberculosis of the middle ear began to develop as exudative middle otitis that acquired the form of bilateral pathology in 4 patients. Three patients had a concomitant pulmonary disease. In 4 patuents, the diagnois of middle ear tuberculosis was established based on the presence of the specific antibodies and in 5 ones based on the

Finite-Element Modelling of the Acoustic Input Admittance of the Newborn Ear Canal and Middle Ear.

PubMed

Motallebzadeh, Hamid; Maftoon, Nima; Pitaro, Jacob; Funnell, W Robert J; Daniel, Sam J

2017-02-01

Admittance measurement is a promising tool for evaluating the status of the middle ear in newborns. However, the newborn ear is anatomically very different from the adult one, and the acoustic input admittance is different than in adults. To aid in understanding the differences, a finite-element model of the newborn ear canal and middle ear was developed and its behaviour was studied for frequencies up to 2000 Hz. Material properties were taken from previous measurements and estimates. The simulation results were within the range of clinical admittance measurements made in newborns. Sensitivity analyses of the material properties show that in the canal model, the maximum admittance and the frequency at which that maximum admittance occurs are affected mainly by the stiffness parameter; in the middle-ear model, the damping is as important as the stiffness in influencing the maximum admittance magnitude but its effect on the corresponding frequency is negligible. Scaling up the geometries increases the admittance magnitude and shifts the resonances to lower frequencies. The results suggest that admittance measurements can provide more information about the condition of the middle ear when made at multiple frequencies around its resonance.

Ear - blocked at high altitudes

MedlinePlus

... ears; Flying and blocked ears; Eustachian tube dysfunction - high altitude ... to the eardrum) and the back of the nose and upper throat. ... down from high altitudes. Chewing gum the entire time you are ...

Klippel-Feil syndrome and associated ear anomalies.

PubMed

Yildirim, Nadir; Arslanoğlu, Atilla; Mahiroğullari, Mahir; Sahan, Murat; Ozkan, Hüseyin

2008-01-01

Klippel-Feil syndrome (KFS) is a congenital segmentation anomaly of the cervical vertebrae that manifests as short neck, low hair line, and limited neck mobility. Various systemic malformations may also accompany the syndrome including wide variety of otopathologies affecting all 3 compartments of the ear (external, middle, and inner ear) as well as internal acoustic canal and vestibular aqueduct. We aimed to investigate these involvements and their clinical correlates in a group of patients with KFS. We present 20 KFS cases, of which 12 (% 60) displayed most of the reported ear abnormalities such as microtia, external ear canal stenosis, chronic ear inflammations and their sequels, anomalies of the tympanic cavity and ossicles, inner ear dysplasies, deformed internal acoustic canal, and wide vestibular aqueduct, which are demonstrated using the methods of otoscopy, audiologic testing, and temporal bone computed tomography. This series represents one of the highest reported rate of ear involvement in KFS. We found no correlation between the identified ear pathologies and the skeletal and extraskeletal malformations. The genetic nature of the syndrome was supported by the existence of affected family members in 4 (20%) of the cases.

Posterior midgut epithelial cells differ in their organization of the membrane skeleton from other drosophila epithelia.

PubMed

Baumann, O

2001-11-01

In epithelial cells, the various components of the membrane skeleton are segregated within specialized subregions of the plasma membrane, thus contributing to the development and stabilization of cell surface polarity. It has previously been shown that, in various Drosophila epithelia, the membrane skeleton components ankyrin and alphabeta-spectrin reside at the lateral surface, whereas alphabeta(H)-spectrin is restricted to the apical domain. By use of confocal immunofluorescence microscopy, the present study characterizes the membrane skeleton of epithelial cells in the posterior midgut, leading to a number of unexpected results. First, ankyrin and alphabeta-spectrin are not detected on the entire lateral surface but appear to be restricted to the apicolateral area, codistributing with fasciclin III at smooth septate junctions. The presumptive ankyrin-binding proteins neuroglian and Na(+),K(+)-ATPase, however, do not colocalize with ankyrin. Second, alphabeta(H)-spectrin is enriched at the apical domain but is also present in lower amounts on the entire lateral surface, colocalizing apicolaterally with ankyrin/alphabeta-spectrin. Finally, despite the absence of zonulae adherentes, F-actin, beta(H)-spectrin, and nonmuscle myosin-II are enriched in the midlateral region. Thus, the model established for the organization of the membrane skeleton in Drosophila epithelia does not hold for the posterior midgut, and there is quite some variability between the different epithelia with respect to the organization of the membrane skeleton. Copyright 2001 Academic Press.

Comparative inner ear transcriptome analysis between the Rickett's big-footed bats (Myotis ricketti) and the greater short-nosed fruit bats (Cynopterus sphinx).

PubMed

Dong, Dong; Lei, Ming; Liu, Yang; Zhang, Shuyi

2013-12-23

Bats have aroused great interests of researchers for the sake of their advanced echolocation system. However, this highly specialized trait is not characteristic of Old World fruit bats. To comprehensively explore the underlying molecular basis between echolocating and non-echolocating bats, we employed a sequence-based approach to compare the inner ear expression difference between the Rickett's big-footed bat (Myotis ricketti, echolocating bat) and the Greater short-nosed fruit bat (Cynopterus sphinx, non-echolocating bat). De novo sequence assemblies were developed for both species. The results showed that the biological implications of up-regulated genes in M. ricketti were significantly over-represented in biological process categories such as 'cochlea morphogenesis', 'inner ear morphogenesis' and 'sensory perception of sound', which are consistent with the inner ear morphological and physiological differentiation between the two bat species. Moreover, the expression of TMC1 gene confirmed its important function in echolocating bats. Our work presents the first transcriptome comparison between echolocating and non-echolocating bats, and provides information about the genetic basis of their distinct hearing traits.

Transmission matrix analysis of the chinchilla middle ear

PubMed Central

Songer, Jocelyn E.; Rosowski, John J.

2008-01-01

Despite the common use of the chinchilla as an animal model in auditory research, a complete characterization of the chinchilla middle ear using transmission matrix analysis has not been performed. In this paper we describe measurements of middle-ear input admittance and stapes velocity in ears with the middle-ear cavity opened under three conditions: intact tympano-ossicular system and cochlea, after the cochlea has been drained, and after the stapes has been fixed. These measurements, made with stimulus frequencies of 100–8000 Hz, are used to define the transmission matrix parameters of the middle ear and to calculate the cochlear input impedance as well as the middle-ear output impedance. This transmission characterization of the chinchilla middle ear will be useful for modeling auditory sensitivity in the normal and pathological chinchilla ear. PMID:17672642

Treating "cauliflower ear" with silicone mold.

PubMed

Gross, C G

1978-01-01

Acute hematoma of the ear (cauliflower ear) can be satisfactorily treated with aspiration and the use of the silicone mold to prevent reaccumulation of the blood or serum in the ear. Advantages of the silicone mold over other dressings appears to be ease of application, patient acceptance, and prevention of reoccurrence of reaccumulation of the hematoma.

Communication routes between intracranial spaces and inner ear: function, pathophysiologic importance and relations with inner ear diseases.

PubMed

Ciuman, Raphael R

2009-01-01

There exist 3 communication routes between the intracranial space and the inner ear, the vestibular aqueduct, the cochlear aqueduct, and the internal auditory canal. They possess a key role in inner ear pressure regulation and fluid homeostasis and are related to inner ear diseases. Relevant literature was reviewed, and the current knowledge of the anatomy, physiologic importance, and relations to inner ear diseases were described. Pathologic communication routes such as semicircular canal dehiscence syndrome were highlighted as well. Abnormalities in all 3 communication routes may predispose or be the cause of distinct inner ear pathologic condition and involved in other cochlear and vestibular syndromes, in which their role is not completely clear. The increasing knowledge of the underlying mechanisms encourages promising approaches for possible intervention in the future.

The neuroecology of cartilaginous fishes: sensory strategies for survival.

PubMed

Collin, Shaun P

2012-01-01

line system, the distribution of electroreceptive pores over the head, and the morphology of the inner ear. These results are presented in the context of predictions of sensory capabilities for species living in a range of ecological niches, what further research is needed, and how this sensory input may be a predictor of behavior. Copyright © 2012 S. Karger AG, Basel.

Molecular Mechanisms of Inner Ear Development

PubMed Central

Wu, Doris K.; Kelley, Matthew W.

2012-01-01

The inner ear is a structurally complex vertebrate organ built to encode sound, motion, and orientation in space. Given its complexity, it is not surprising that inner ear dysfunction is a relatively common consequence of human genetic mutation. Studies in model organisms suggest that many genes currently known to be associated with human hearing impairment are active during embryogenesis. Hence, the study of inner ear development provides a rich context for understanding the functions of genes implicated in hearing loss. This chapter focuses on molecular mechanisms of inner ear development derived from studies of model organisms. PMID:22855724

Molecular mechanisms of inner ear development.

PubMed

Wu, Doris K; Kelley, Matthew W

2012-08-01

The inner ear is a structurally complex vertebrate organ built to encode sound, motion, and orientation in space. Given its complexity, it is not surprising that inner ear dysfunction is a relatively common consequence of human genetic mutation. Studies in model organisms suggest that many genes currently known to be associated with human hearing impairment are active during embryogenesis. Hence, the study of inner ear development provides a rich context for understanding the functions of genes implicated in hearing loss. This chapter focuses on molecular mechanisms of inner ear development derived from studies of model organisms.

Expanded Terminal Fields of Gustatory Nerves Accompany Embryonic BDNF Overexpression in Mouse Oral Epithelia

PubMed Central

Sun, Chengsan; Dayal, Arjun

2015-01-01

Brain-derived neurotrophic factor (BDNF) is expressed in gustatory epithelia and is required for gustatory neurons to locate and innervate their correct target during development. When BDNF is overexpressed throughout the lingual epithelium, beginning embryonically, chorda tympani fibers are misdirected and innervate inappropriate targets, leading to a loss of taste buds. The remaining taste buds are hyperinnervated, demonstrating a disruption of nerve/target matching in the tongue. We tested the hypothesis here that overexpression of BDNF peripherally leads to a disrupted terminal field organization of nerves that carry taste information to the brainstem. The chorda tympani, greater superficial petrosal, and glossopharyngeal nerves were labeled in adult wild-type (WT) mice and in adult mice in which BDNF was overexpressed (OE) to examine the volume and density of their central projections in the nucleus of the solitary tract. We found that the terminal fields of the chorda tympani and greater superficial petrosal nerves and overlapping fields that included these nerves in OE mice were at least 80% greater than the respective field volumes in WT mice. The shapes of terminal fields were similar between the two groups; however, the density and spread of labels were greater in OE mice. Unexpectedly, there were also group-related differences in chorda tympani nerve function, with OE mice showing a greater relative taste response to a concentration series of sucrose. Overall, our results show that disruption in peripheral innervation patterns of sensory neurons have significant effects on peripheral nerve function and central organization of their terminal fields. PMID:25568132

Middle ear impedance measurements in large vestibular aqueduct syndrome.

PubMed

Bilgen, Cem; Kirkim, Günay; Kirazli, Tayfun

2009-06-01

To assess the effect of inner ear pressure on middle ear impedance in patients with large vestibular aqueduct syndrome (LVAS). Data from admittance tympanometry and multifrequency tympanometry on 8 LVAS patients and control subjects were studied. Static acoustic compliance (SAC) values for the ears with stable sensorineural hearing loss (SNHL) were within the limits of the mean values of control groups except for two ears. The resonance frequency (RF) values of the ears with stable SNHL were lower than the mean values of control groups except for three ears. SAC values for the two ears with fluctuating SNHL were lower and the RF values were higher than the mean values of control groups. Decreased SAC values and increased RF values found in the ears with fluctuating SNHL might be an indirect indicator of increased inner ear pressure, while low RF values in the ears with stable SNHL might reflect the decreased inner ear impedance.

Three-dimensional Architecture of Hair-bundle Linkages Revealed by Electron-microscopic Tomography

PubMed Central

Auer, Manfred; Koster, Abrahram J.; Ziese, Ulrike; Bajaj, Chandrajit; Volkmann, Niels; Wang, Da Neng

2008-01-01

The senses of hearing and balance rest upon mechanoelectrical transduction by the hair bundles of hair cells in the inner ear. Located at the apical cellular surface, each hair bundle comprises several tens of stereocilia and a single kinocilium that are interconnected by extracellular proteinaceous links. Using electron-microscopic tomography of bullfrog saccular sensory epithelia, we examined the three-dimensional structures of basal links, kinociliary links, and tip links. We observed significant differences in the appearances and dimensions of these three structures and found two distinct populations of tip links suggestive of the involvement of different proteins, splice variants, or protein–protein interactions. We noted auxiliary links connecting the upper portions of tip links to the taller stereocilia. Tip links and auxiliary links show a tendency to adopt a globular conformation when disconnected from the membrane surface. PMID:18421501

Deriving the real-ear SPL of audiometric data using the "coupler to dial difference" and the "real ear to coupler difference".

PubMed

Munro, K J; Davis, J

2003-04-01

The purpose of the study was to compare the measured real-ear sound pressure level (SPL) of audiometer output with the derived real-ear SPL obtained by adding the coupler to dial difference (CDD) and real-ear to coupler difference (RECD) to the audiometer dial reading. The real-ear SPL and RECD were measured in one ear of 16 normally hearing subjects using a probe-tube microphone. The CDD transform and the RECD transfer function were measured in an HA1 and an HA2 2-cc coupler using an EAR-LINK foam ear-tip or a customized earmold. The RECD transfer function was measured using the EARTone ER 3A and the Audioscan RE770 insert earphone. The procedures were very reliable with mean differences on retest of less than 1 dB. The mean difference between the measured and derived real-ear SPL was generally less than 1 dB and rarely exceeded 3 dB in any subject. The CDD measured for an individual audiometer and the RECD measured for an individual ear can be used to derive a valid estimate of real-ear SPL when it has not been possible to measure this directly.

Comparison of Microbiological Flora in the External Auditory Canal of Normal Ear and an Ear with Acute Otitis Externa.

PubMed

Ghanpur, Asheesh Dora; Nayak, Dipak Ranjan; Chawla, Kiran; Shashidhar, V; Singh, Rohit

2017-09-01

Acute Otitis Externa (AOE) is also known as swimmer's ear. Investigations initiated during World War II firmly established the role of bacteria in the aetiology of Acute Otitis Externa. To culture the microbiological flora of the normal ear and compare it with the flora causing AOE and to know the role of normal ear canal flora and anaerobes in the aetiology. A prospective observational study was conducted on 64 patients clinically diagnosed with unilateral AOE. Ear swabs were taken from both the ears. Microbiological flora was studied considering diseased ear as test ear and the normal ear as the control. Aerobic and anaerobic cultures were done. Severity of the disease was assessed by subjective and objective scores. Effect of topical treatment with ichthammol glycerine pack was assessed after 48 hours and scores were calculated again. Patients with scores < 4 after pack removal were started on systemic antibiotics and were assessed after seven days of antibiotics course. Data was analysed using Paired t-test, Wilcoxon signed ranks test and Chi-square test. A p-value < 0.05 was considered significant. Pseudomonas aeruginosa (33%) was the most common bacteria cultured from the ear followed by Methicillin Resistant Staphylococcus aureus (MRSA) (18%). Patients with anaerobic organism in the test ear had severe symptoms and needed systemic antibiotic therapy. Most of the cases may respond to empirical antibiotic therapy. In cases with severe symptoms and the ones refractory to empirical treatment, a culture from the ear canal will not be a tax on the patient. This helps in giving a better understanding about the disease, causative organisms and helps in avoiding the use of inappropriate antibiotics that usually result in developing resistant strains of bacteria.

An optimal state estimation model of sensory integration in human postural balance

NASA Astrophysics Data System (ADS)

Kuo, Arthur D.

2005-09-01

We propose a model for human postural balance, combining state feedback control with optimal state estimation. State estimation uses an internal model of body and sensor dynamics to process sensor information and determine body orientation. Three sensory modalities are modeled: joint proprioception, vestibular organs in the inner ear, and vision. These are mated with a two degree-of-freedom model of body dynamics in the sagittal plane. Linear quadratic optimal control is used to design state feedback and estimation gains. Nine free parameters define the control objective and the signal-to-noise ratios of the sensors. The model predicts statistical properties of human sway in terms of covariance of ankle and hip motion. These predictions are compared with normal human responses to alterations in sensory conditions. With a single parameter set, the model successfully reproduces the general nature of postural motion as a function of sensory environment. Parameter variations reveal that the model is highly robust under normal sensory conditions, but not when two or more sensors are inaccurate. This behavior is similar to that of normal human subjects. We propose that age-related sensory changes may be modeled with decreased signal-to-noise ratios, and compare the model's behavior with degraded sensors against experimental measurements from older adults. We also examine removal of the model's vestibular sense, which leads to instability similar to that observed in bilateral vestibular loss subjects. The model may be useful for predicting which sensors are most critical for balance, and how much they can deteriorate before posture becomes unstable.

Expression Analysis of the Transmembrane Mucin MUC20 in Human Corneal and Conjunctival Epithelia

PubMed Central

Woodward, Ashley M.; Argüeso, Pablo

2014-01-01

Purpose. Cell surface mucins are a group of highly O-glycosylated transmembrane glycoproteins responsible for the protection of epithelial cells on mucosal surfaces. The aim of this study was to investigate the localization and regulation of mucin 20 (MUC20) at the ocular surface. Methods. Localization of MUC20 in human corneal and conjunctival epithelia was evaluated by immunofluorescence microscopy. Immortalized corneal (HCLE) and conjunctival (HCjE) cell lines were grown at different stages of differentiation and subjected to quantitative PCR and Western blot analyses. Cell surface proteins on apical cell membranes were biotinylated and isolated by neutravidin chromatography. Results. The MUC20 was detected throughout the entire human ocular surface epithelia, predominantly in cell membranes within intermediate cell layers. In conjunctiva, MUC20 also was observed in the cytoplasm of apical cells within the stratified squamous epithelium, but not in goblet cells. Quantitative PCR and immunoblotting demonstrated expression of MUC20 in HCLE and HCjE cells. Induction of differentiation with serum-containing medium resulted in upregulation of MUC20 mRNA and protein. Biotin labeling of the surface of stratified cultures revealed low levels of MUC20 protein on apical glycocalyces. Further, MUC20 was not detected in the cell culture media or in human tears, suggesting that the extracellular domain of MUC20 is not released from the ocular surface as described previously for other cell surface mucins. Conclusions. Our results indicate that MUC20 is a novel transmembrane mucin expressed by the human corneal and conjunctival epithelia, and suggest that differential expression of MUC20 during differentiation has a role in maintaining ocular surface homeostasis. PMID:25168902

Middle-ear velocity transfer function, cochlear input immittance, and middle-ear efficiency in chinchilla.

PubMed

Ravicz, Michael E; Rosowski, John J

2013-10-01

The transfer function H(V) between stapes velocity V(S) and sound pressure near the tympanic membrane P(TM) is a descriptor of sound transmission through the middle ear (ME). The ME power transmission efficiency (MEE), the ratio of sound power entering the cochlea to power entering the middle ear, was computed from H(V) measured in seven chinchilla ears and previously reported measurements of ME input admittance Y(TM) and ME pressure gain G(MEP) [Ravicz and Rosowski, J. Acoust. Soc. Am. 132, 2437-2454 (2012); J. Acoust. Soc. Am. 133, 2208-2223 (2013)] in the same ears. The ME was open, and a pressure sensor was inserted into the cochlear vestibule for most measurements. The cochlear input admittance Y(C) computed from H(V) and G(MEP) is controlled by a combination of mass and resistance and is consistent with a minimum-phase system up to 27 kHz. The real part Re{Y(C)}, which relates cochlear sound power to inner-ear sound pressure, decreased gradually with frequency up to 25 kHz and more rapidly above that. MEE was about 0.5 between 0.1 and 8 kHz, higher than previous estimates in this species, and decreased sharply at higher frequencies.

Middle-ear velocity transfer function, cochlear input immittance, and middle-ear efficiency in chinchilla

PubMed Central

Ravicz, Michael E.; Rosowski, John J.

2013-01-01

The transfer function HV between stapes velocity VS and sound pressure near the tympanic membrane PTM is a descriptor of sound transmission through the middle ear (ME). The ME power transmission efficiency (MEE), the ratio of sound power entering the cochlea to power entering the middle ear, was computed from HV measured in seven chinchilla ears and previously reported measurements of ME input admittance YTM and ME pressure gain GMEP [Ravicz and Rosowski, J. Acoust. Soc. Am. 132, 2437–2454 (2012); J. Acoust. Soc. Am. 133, 2208–2223 (2013)] in the same ears. The ME was open, and a pressure sensor was inserted into the cochlear vestibule for most measurements. The cochlear input admittance YC computed from HV and GMEP is controlled by a combination of mass and resistance and is consistent with a minimum-phase system up to 27 kHz. The real part Re{YC}, which relates cochlear sound power to inner-ear sound pressure, decreased gradually with frequency up to 25 kHz and more rapidly above that. MEE was about 0.5 between 0.1 and 8 kHz, higher than previous estimates in this species, and decreased sharply at higher frequencies. PMID:24116422

CT of the ear in Pendred syndrome.

PubMed

Goldfeld, Moshe; Glaser, Benjamin; Nassir, Elias; Gomori, John Moshe; Hazani, Elitsur; Bishara, Nassir

2005-05-01

To prospectively determine the structural anomalies of the inner ear by using thin-section computed tomography (CT) in an extended family with Pendred syndrome. Ethics committee approved the study, and informed consent was obtained from every patient or from parents of patients under legal age. Twelve patients (three females and nine males aged 7-47 years) with Pendred syndrome (all from the same ethnic isolate and with the same mutation in the PDS gene) were evaluated for inner-ear malformation at thin-section CT. Both ears were evaluated. Presence or absence of interscalar septum between upper and middle turns of the cochlea was evaluated, and vestibule and vestibular aqueduct were examined for enlargement. Modiolus was determined to be present or absent (modiolar deficiency). CT scans were evaluated in consensus by two radiologists (M.G., J.M.G.). All patients had inner ear malformation on both sides. Modiolus was absent and vestibule was enlarged on both sides in all 12 patients. Interscalar septum was absent in 18 (75%) of 24 ears. In eight patients, interscalar septum was absent in both ears, whereas in two patients, it was absent on only one side. Aqueduct was enlarged in 20 (80%) of 24 ears. In nine patients, both ears had enlarged aqueducts, while in two patients, only one side was abnormal. Inner ear malformation is an invariable finding in Pendred syndrome. Modiolus deficiency and vestibular enlargement were the most consistent anomalies in this population with Pendred syndrome. (c) RSNA, 2005.

The ideal ear position in Caucasian females.

PubMed

Broer, P Niclas; Thiha, Aung; Ehrl, Denis; Sinno, Sammy; Juran, Sabrina; Szpalski, Caroline; Ng, Reuben; Ninkovic, Milomir; Prantl, Lukas; Heidekrueger, Paul I

2018-03-01

Ear position contributes significantly to facial appearance. However, while objective measurements remain the foundation for esthetic evaluations, little is known about how an ear should ideally be positioned regarding its rotational axis. This study aimed to further evaluate whether there exists a universally applicable ideal ear axis, and how sociodemographic factors impact such preferences. An interactive online survey was designed, enabling participants to change the axis of a female model's ear in terms of its forward and backward rotation. The questionnaire was sent out internationally to plastic surgeons and the general public. Demographic data were collected and analysis of variance was used to investigate respective preferences. A total of 1016 responses from 35 different countries (response rate: 18.5%) were gathered. Overall, 60% of survey takers chose the minus 10 or 5° angles to be most attractive. Significant differences were found regarding sex, ethnicity, country of residence, profession and respective ear axis preferences. Across multiple countries and ethnicities, an ear position in slight reclination of minus 5-10° is considered most pleasing in Caucasian females. However, sociodemographic factors significantly impact individual ear axis preferences and should be taken into consideration when performing reconstructive ear surgery. Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Numerical analysis of ossicular chain lesion of human ear

NASA Astrophysics Data System (ADS)

Liu, Yingxi; Li, Sheng; Sun, Xiuzhen

2009-04-01

Lesion of ossicular chain is a common ear disease impairing the sense of hearing. A comprehensive numerical model of human ear can provide better understanding of sound transmission. In this study, we propose a three-dimensional finite element model of human ear that incorporates the canal, tympanic membrane, ossicular bones, middle ear suspensory ligaments/muscles, middle ear cavity and inner ear fluid. Numerical analysis is conducted and employed to predict the effects of middle ear cavity, malleus handle defect, hypoplasia of the long process of incus, and stapedial crus defect on sound transmission. The present finite element model is shown to be reasonable in predicting the ossicular mechanics of human ear.

[Constricted ear therapy with free auricular composite grafts].

PubMed

Liu, Tun; Zhang, Lian-sheng; Zhuang, Hong-xing; Zhang, Ke-yuan

2004-03-01

A simple and effective therapy for single side constricted ear. Transplanting normal side free composite auricular grafts to constricted ear (15 patients and 15 sides), then lengthening the helix, exposing the scapha, correcting deformity. The 15 patients composite grafts all survived. The helix has been lengthened, the scapha exposed, the normal ear reduced, the constricted ear augmented and two sides ear have become symmetry. This method is simple and results are satisfied.

Expression of macrophage migration inhibitory factor and CD74 in the inner ear and middle ear in lipopolysaccharide-induced otitis media.

PubMed

Ishihara, Hisashi; Kariya, Shin; Okano, Mitsuhiro; Zhao, Pengfei; Maeda, Yukihide; Nishizaki, Kazunori

2016-10-01

Significant expression of macrophage migration inhibitory factor and its receptor (CD74) was observed in both the middle ear and inner ear in experimental otitis media in mice. Modulation of macrophage migration inhibitory factor and its signaling pathway might be useful in the management of inner ear inflammation due to otitis media. Inner ear dysfunction secondary to otitis media has been reported. However, the specific mechanisms involved are not clearly understood. The aim of this study is to investigate the expression of macrophage migration inhibitory factor and CD74 in the middle ear and inner ear in lipopolysaccharide-induced otitis media. BALB/c mice received a transtympanic injection of either lipopolysaccharide or phosphate-buffered saline (PBS). The mice were sacrificed 24 h after injection, and temporal bones were processed for polymerase chain reaction (PCR) analysis, histologic examination, and immunohistochemistry. PCR examination revealed that the lipopolysaccharide-injected mice showed a significant up-regulation of macrophage migration inhibitory factor in both the middle ear and inner ear as compared with the PBS-injected control mice. The immunohistochemical study showed positive reactions for macrophage migration inhibitory factor and CD74 in infiltrating inflammatory cells, middle ear mucosa, and inner ear in the lipopolysaccharide-injected mice.

Expression of pluripotency factors in larval epithelia of the frog Xenopus: Evidence for the presence of cornea epithelial stem cells

PubMed Central

Perry, Kimberly J.; Thomas, Alvin G.; Henry, Jonathan J.

2013-01-01

Understanding the biology of somatic stem cells in self renewing tissues represents an exciting field of study, especially given the potential to harness these cells for tissue regeneration and repair in treating injury and disease. The mammalian cornea contains a population of basal epithelial stem cells involved in cornea homeostasis and repair. Research has been restricted to mammalian systems and little is known about the presence or function of these stem cells in other vertebrates. Therefore, we carried out studies to characterize frog cornea epithelium. Careful examination shows that the Xenopus larval cornea epithelium consists of three distinct layers that include an outer epithelial layer and underlying basal epithelium, in addition to a deeper fibrous layer that contains the main sensory nerve trunks that give rise to numerous branches that extend into these epithelia. These nerves convey sensory and presumably also autonomic innervation to those tissues. The sensory nerves are all derived as branches of the trigeminal nerve/ganglion similar to the situation encountered in mammals, though there appear to be some potentially interesting differences, which are detailed in this paper. We show further that numerous pluripotency genes are expressed by cells in the cornea epithelium, including: sox2, p63, various oct4 homologs, c-myc, klf4 and many others. Antibody localization revealed that p63, a well known mammalian epithelial stem cell marker, was localized strictly to all cells in the basal cornea epithelium. c-myc, was visualized in a smaller subset of basal epithelial cells and adjacent stromal tissue predominately at the periphery of the cornea (limbal zone). Finally, sox2 protein was found to be present throughout all cells of both the outer and basal epithelia, but was much more intensely expressed in a distinct subset of cells that appeared to be either multinucleate or possessed multi-lobed nuclei that are normally located at the periphery of the

The comparative anatomy of the pig middle ear cavity: a model for middle ear inflammation in the human?

PubMed Central

PRACY, J. P.; WHITE, A.; MUSTAFA, Y.; SMITH, D.; PERRY, M. E.

1998-01-01

This study was undertaken to develop a functional model of otitis media with effusion (OME) in the pig (Sus scrofa), with the purpose of investigating the origin of lymphocytes populating the middle ear during the course of an inflammatory process. The relevance of the model to the human condition of OME is to a large extent dependent on the anatomical and physiological similarities between the middle ear cavity and the pharyngeal lymphoid tissue of the pig and man. Anatomical specimens were collected from 7 young Large White pigs to determine the gross anatomy of the middle ear cavity and the histological characteristics of the middle ear mucosa. It was found that the anatomy of the 3 parts of the middle ear cavity in man and in the pig is broadly similar, although some minor differences were observed. The porcine eustachian tube was seen to be cartilaginous throughout its length in contrast to the part osseous, part cartilaginous structure found in man; the porcine ossicles were slightly different in shape to those of man and the air cell system was situated inferior to the tympanic cavity in the pig as opposed to posteriorly in man. This paper describes the structure and morphology of the pig middle ear cavity and compares and contrasts it with that of man. The minor differences observed are of anatomical importance but do not diminish the usefulness of the pig middle ear cleft as a potential model for human middle ear disorders. PMID:9688502

Ruminal and Abomasal Starch Hydrolysate Infusions Selectively Decrease the Expression of Cationic Amino Acid Transporter mRNA by Small Intestinal Epithelia of Forage-fed Beef Steers

USDA-ARS?s Scientific Manuscript database

Although cationic amino acids (CAA) are consid-ered essential to maximize optimal growth of cattle, transporters responsible for CAA absorption by bovine small intestinal epithelia have not been described. This study was conducted to test 2 hypotheses: 1) the duo¬denal, jejunal, and ileal epithelia ...

Facial Asymmetry: Brow and Ear Position.

PubMed

Perumal, Balaji; Meyer, Dale R

2018-04-01

The purpose of the current study was to analyze brow and ear position, and examine the relationship between these structures in patients presenting for blepharoplasty evaluation. A retrospective chart review was performed, which included all patients presenting to one oculoplastic physician for a blepharoplasty evaluation from November, 2012 to March, 2014. The prevalence of brow ptosis and brow and ear asymmetry was calculated; the proportional distribution was determined, and chi-square analysis and the z-test of proportions were used to calculate the significance. Institutional Review Board approval was obtained for this study. A total of 133 patients met the inclusion criteria. Some degree of brow ptosis was noted in 83% of patients. Brow asymmetry was found in 88% of patients, and ear asymmetry in 77%. Of those patients who had asymmetry, 61% had the right brow lower and 75% had the right ear lower; 73% of all patients had the brow and ear lower on the same side ( p  < 0.001). In this study, brow ptosis and asymmetry were quite common. In addition, the side of the lower brow correlated strongly with the side of the lower ear, and the right side structures were lower more often than the left. Patients presenting for blepharoplasty evaluation may have an element of generalized facial asymmetry which includes the brows and ears. These observations can be important for preoperative planning and patient counseling. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Biometric recognition using 3D ear shape.

PubMed

Yan, Ping; Bowyer, Kevin W

2007-08-01

Previous works have shown that the ear is a promising candidate for biometric identification. However, in prior work, the preprocessing of ear images has had manual steps and algorithms have not necessarily handled problems caused by hair and earrings. We present a complete system for ear biometrics, including automated segmentation of the ear in a profile view image and 3D shape matching for recognition. We evaluated this system with the largest experimental study to date in ear biometrics, achieving a rank-one recognition rate of 97.8 percent for an identification scenario and an equal error rate of 1.2 percent for a verification scenario on a database of 415 subjects and 1,386 total probes.

Ick Ciliary Kinase Is Essential for Planar Cell Polarity Formation in Inner Ear Hair Cells and Hearing Function.

PubMed

Okamoto, Shio; Chaya, Taro; Omori, Yoshihiro; Kuwahara, Ryusuke; Kubo, Shun; Sakaguchi, Hirofumi; Furukawa, Takahisa

2017-02-22

Cellular asymmetries play crucial roles in development and organ function. The planar cell polarity (PCP) signaling pathway is involved in the establishment of cellular asymmetry within the plane of a cell sheet. Inner ear sensory hair cells (HCs), which have several rows of staircase-like stereocilia and one kinocilium located at the vertex of the stereocilia protruding from the apical surface of each HC, exhibit a typical form of PCP. Although connections between cilia and PCP signaling in vertebrate development have been reported, their precise nature is not well understood. During inner ear development, several ciliary proteins are known to play a role in PCP formation. In the current study, we investigated a functional role for intestinal cell kinase (Ick), which regulates intraflagellar transport (IFT) at the tip of cilia, in the mouse inner ear. A lack of Ick in the developing inner ear resulted in PCP defects in the cochlea, including misorientation or misshaping of stereocilia and aberrant localization of the kinocilium and basal body in the apical and middle turns, leading to auditory dysfunction. We also observed abnormal ciliary localization of Ift88 in both HCs and supporting cells. Together, our results show that Ick ciliary kinase is essential for PCP formation in inner ear HCs, suggesting that ciliary transport regulation is important for PCP signaling. SIGNIFICANCE STATEMENT The cochlea in the inner ear is the hearing organ. Planar cell polarity (PCP) in hair cells (HCs) in the cochlea is essential for mechanotransduction and refers to the asymmetric structure consisting of stereociliary bundles and the kinocilium on the apical surface of the cell body. We reported previously that a ciliary kinase, Ick, regulates intraflagellar transport (IFT). Here, we found that loss of Ick leads to abnormal localization of the IFT component in kinocilia, PCP defects in HCs, and hearing dysfunction. Our study defines the association of ciliary transport

Acceleration induced water removal from ear canals.

NASA Astrophysics Data System (ADS)

Kang, Hosung; Averett, Katelee; Jung, Sunghwan

2017-11-01

Children and adults commonly experience having water trapped in the ear canals after swimming. To remove the water, individuals will shake their head sideways. Since a child's ear canal has a smaller diameter, it requires more acceleration of the head to remove the trapped water. In this study, we theoretically and experimentally investigated the acceleration required to break the surface meniscus of the water in artificial ear canals and hydrophobic-coated glass tubes. In experiments, ear canal models were 3D-printed from a CT-scanned human head. Also, glass tubes were coated with silane to match the hydrophobicity in ear canals. Then, using a linear stage, we measured the acceleration values required to forcefully eject the water from the artificial ear canals and glass tubes. A theoretical model was developed to predict the critical acceleration at a given tube diameter and water volume by using a modified Rayleigh-Taylor instability. Furthermore, this research can shed light on the potential of long-term brain injury and damage by shaking the head to push the water out of the ear canal. This research was supported by National Science Foundation Grant CBET-1604424.

Passage of albumin from the middle ear to the inner ear in otitis media in the chinchilla

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldberg, B.; Goycoolea, M.V.; Schleivert, P.M.

1981-08-01

A study of the permeability of the middle ear-inner ear interface for macromolecules was carried out in chinchillas with open and obstructed eustachian tubes utilizing tritiated human serum albumin and immunoelectrophoresis. Tritiated albumin was placed in the round window niche area or normal animals and animals in which the eustachian tubes had been obstructed for 24 hours or 14 days. The tritiated albumin was allowed to remain in the middle ear cavity for 24 hours, Samples of middle ear effusion, perilymph, blood and cerebrospinal fluid were collected and measured for radioactivity. Radioactivity was demonstrated in the perilymph. Samples of middlemore » ear effusions and perilymph were also studied by immunoelectrophoresis with goat antihuman albumin. Albumin placed in the round window niche of an experimental animal could be recovered unchanged in the perilymph. The results suggest a pathophysiologic explanation for the association of otitis media and sensorineural hearing loss or endolymphatic hydrops.« less

Fly-ear inspired acoustic sensors for gunshot localization

NASA Astrophysics Data System (ADS)

Liu, Haijun; Currano, Luke; Gee, Danny; Yang, Benjamin; Yu, Miao

2009-05-01

The supersensitive ears of the parasitoid fly Ormia ochracea have inspired researchers to develop bio-inspired directional microphone for sound localization. Although the fly ear is optimized for localizing the narrow-band calling song of crickets at 5 kHz, experiments and simulation have shown that it can amplify directional cues for a wide frequency range. In this article, a theoretical investigation is presented to study the use of fly-ear inspired directional microphones for gunshot localization. Using an equivalent 2-DOF model of the fly ear, the time responses of the fly ear structure to a typical shock wave are obtained and the associated time delay is estimated by using cross-correlation. Both near-field and far-field scenarios are considered. The simulation shows that the fly ear can greatly amplify the time delay by ~20 times, which indicates that with an interaural distance of only 1.2 mm the fly ear is able to generate a time delay comparable to that obtained by a conventional microphone pair with a separation as large as 24 mm. Since the parameters of the fly ear structure can also be tuned for muzzle blast and other impulse stimulus, fly-ear inspired acoustic sensors offers great potential for developing portable gunshot localization systems.

Incorporating anthropometry into design of ear-related products.

PubMed

Liu, Bor-Shong

2008-01-01

To achieve mass customization and collaborative product design, human factors and ergonomics should play a key development role. The purpose of this study was to provide product designers with the anthropometic dimensions of outer ears for different demographic data, including gender and age. The second purpose was to compare the dimensions of various ear-related products (i.e., earphone, bluetooth earphone and ear-cup earphone) with the anthropometic database and recommend appropriate solutions for design. Two hundred subjects aged 20-59 was selected for this study and divided into four age stratifications. Further, three different dimensions of the outer ear (i.e., the earhole length, the ear connection length and the length of the pinna) were measured by superimposed grid photographic technique. The analysis of variance (ANOVA) was used to investigate the effects of gender, and age on ear dimensions. The results showed that all ear dimensions had significant gender effects. A comparison between the anthropometric dimensions and those of current products revealed that most current ear-related products need to be redesigned using anthropometric data. The shapes of earhole and pinna are not circular. Consequently, ear products need to be elongated so that users may feel more comfortably and not have the product slip off easily.

Pinna abnormalities and low-set ears

MedlinePlus

... Pinna abnormalities; Genetic defect - pinna; Congenital defect - pinna Images Ear abnormalities Pinna of the newborn ear References Haddad J, Keesecker S. Congenital malformations. In: Kliegman RM, Stanton BF, ...

Clearance of Apoptotic Cells by Tissue Epithelia: A Putative Role for Hepatocytes in Liver Efferocytosis

PubMed Central

Davies, Scott P.; Reynolds, Gary M.; Stamataki, Zania

2018-01-01

Toxic substances and microbial or food-derived antigens continuously challenge the liver, which is tasked with their safe neutralization. This vital organ is also important for the removal of apoptotic immune cells during inflammation and has been previously described as a “graveyard” for dying lymphocytes. The clearance of apoptotic and necrotic cells is known as efferocytosis and is a critical liver function to maintain tissue homeostasis. Much of the research into this form of immunological control has focused on Kupffer cells, the liver-resident macrophages. However, hepatocytes (and other liver resident cells) are competent efferocytes and comprise 80% of the liver mass. Little is known regarding the mechanisms of apoptotic and necrotic cell capture by epithelia, which lack key receptors that mediate phagocytosis in macrophages. Herein, we discuss recent developments that increased our understanding of efferocytosis in tissues, with a special focus on the liver parenchyma. We discuss the impact of efferocytosis in health and in inflammation, highlighting the role of phagocytic epithelia. PMID:29422896

Engraftment of Human Pluripotent Stem Cell-derived Progenitors in the Inner Ear of Prenatal Mice.

PubMed

Takeda, Hiroki; Hosoya, Makoto; Fujioka, Masato; Saegusa, Chika; Saeki, Tsubasa; Miwa, Toru; Okano, Hideyuki; Minoda, Ryosei

2018-01-31

There is, at present, no curative treatment for genetic hearing loss. We have previously reported that transuterine gene transfer of wild type CONNEXIN30 (CX30) genes into otocysts in CX30-deleted mice could restore hearing. Cell transplantation therapy might be another therapeutic option, although it is still unknown whether stem cell-derived progenitor cells could migrate into mouse otocysts. Here, we show successful cell transplantation of progenitors of outer sulcus cell-like cells derived from human-derived induced pluripotent stem cells into mouse otocysts on embryonic day 11.5. The delivered cells engrafted more frequently in the non-sensory region in the inner ear of CX30-deleted mice than in wild type mice and survived for up to 1 week after transplantation. Some of the engrafted cells expressed CX30 proteins in the non-sensory region. This is the first report that demonstrates successful engraftment of exogenous cells in prenatal developing otocysts in mice. Future studies using this mouse otocystic injection model in vivo will provide further clues for developing treatment modalities for congenital hearing loss in humans.

Single-stage autologous ear reconstruction for microtia.

PubMed

Kasrai, Leila; Snyder-Warwick, Alison K; Fisher, David M

2014-03-01

The authors have been using the Nagata technique since 2002. In this review of 100 consecutive ear reconstructions, the authors present technique modifications that have evolved over this period that have contributed to improved auricular contour and that now allow for auricular reconstruction in a single stage. This study is a retrospective review of a prospectively acquired database. The series is restricted to primary reconstructions performed for congenital microtia. Photographs of 10 consecutive patients are presented to demonstrate the results of the technique. Surgical complication rates are discussed. One hundred ear reconstructions were performed in 96 patients. There were 75 primary cases of congenital microtia. Twenty-four ears underwent a two-stage reconstruction, and 51 ears were reconstructed with a Nagata stage I procedure or a single-stage reconstruction. There was a gradual shift in technique, with a trend to perform fewer Nagata stage II outsetting procedures and more single-stage reconstructions. In patients who underwent an ear reconstruction in two stages, the surgical complication rate was 22 percent. In the last 40 consecutive ear reconstructions since abandoning the two-stage approach, the surgical complication rate is now 15 percent. A modification of Nagata's technique of autologous ear reconstruction for microtia is described. Modifications of the three-dimensional framework address the contour of the inferior crus and control tragal projection and position. Inclusion of a projection block and recruitment of retroauricular skin allow for symmetric projection of the ear in a single stage. Therapeutic, IV.

Audiometric Predictions Using SFOAE and Middle-Ear Measurements

PubMed Central

Ellison, John C.; Keefe, Douglas H.

2006-01-01

Objective The goals of the study are to determine how well stimulus-frequency otoacoustic emissions (SFOAEs) identify hearing loss, classify hearing loss as mild or moderate-severe, and correlate with pure-tone thresholds in a population of adults with normal middle-ear function. Other goals are to determine if middle-ear function as assessed by wideband acoustic transfer function (ATF) measurements in the ear canal account for the variability in normal thresholds, and if the inclusion of ATFs improves the ability of SFOAEs to identify hearing loss and predict pure-tone thresholds. Design The total suppressed SFOAE signal and its corresponding noise were recorded in 85 ears (22 normal ears and 63 ears with sensorineural hearing loss) at octave frequencies from 0.5 – 8 kHz using a nonlinear residual method. SFOAEs were recorded a second time in three impaired ears to assess repeatability. Ambient-pressure ATFs were obtained in all but one of these 85 ears, and were also obtained from an additional 31 normal-hearing subjects in whom SFOAE data were not obtained. Pure-tone air-and bone-conduction thresholds and 226-Hz tympanograms were obtained on all subjects. Normal tympanometry and the absence of air-bone gaps were used to screen subjects for normal middle-ear function. Clinical decision theory was used to assess the performance of SFOAE and ATF predictors in classifying ears as normal or impaired, and linear regression analysis was used to test the ability of SFOAE and ATF variables to predict the air-conduction audiogram. Results The ability of SFOAEs to classify ears as normal or hearing impaired was significant at all test frequencies. The ability of SFOAEs to classify impaired ears as either mild or moderate-severe was significant at test frequencies from 0.5 to 4 kHz. SFOAEs were present in cases of severe hearing loss. SFOAEs were also significantly correlated with air-conduction thresholds from 0.5 to 8 kHz. The best performance occurred using the SFOAE

An Effective 3D Ear Acquisition System

PubMed Central

Liu, Yahui; Lu, Guangming; Zhang, David

2015-01-01

The human ear is a new feature in biometrics that has several merits over the more common face, fingerprint and iris biometrics. It can be easily captured from a distance without a fully cooperative subject. Also, the ear has a relatively stable structure that does not change much with the age and facial expressions. In this paper, we present a novel method of 3D ear acquisition system by using triangulation imaging principle, and the experiment results show that this design is efficient and can be used for ear recognition. PMID:26061553

An Effective 3D Ear Acquisition System.

PubMed

Liu, Yahui; Lu, Guangming; Zhang, David

2015-01-01

The human ear is a new feature in biometrics that has several merits over the more common face, fingerprint and iris biometrics. It can be easily captured from a distance without a fully cooperative subject. Also, the ear has a relatively stable structure that does not change much with the age and facial expressions. In this paper, we present a novel method of 3D ear acquisition system by using triangulation imaging principle, and the experiment results show that this design is efficient and can be used for ear recognition.

Animal models of middle ear cholesteatoma.

PubMed

Yamamoto-Fukuda, Tomomi; Takahashi, Haruo; Koji, Takehiko

2011-01-01

Middle ear acquired cholesteatoma is a pathological condition associated with otitis media, which may be associated with temporal bone resorption, otorrhea and hearing loss, and occasionally various other complications. Cholesteatoma is characterized by the enhanced proliferation of epithelial cells with aberrant morphologic characteristics. Unfortunately, our understanding of the mechanism underlying its pathogenesis is limited. To investigate its pathogenesis, different animal models have been used. This paper provides a brief overview of the current status of research in the field of pathogenesis of middle ear acquired cholesteatoma, four types of animal models previously reported on, up-to-date cholesteatoma research using these animal models, our current studies of the local hybrid ear model, and the future prospect of new animal models of middle ear cholesteatoma.

Animal Models of Middle Ear Cholesteatoma

PubMed Central

Yamamoto-Fukuda, Tomomi; Takahashi, Haruo; Koji, Takehiko

2011-01-01

Middle ear acquired cholesteatoma is a pathological condition associated with otitis media, which may be associated with temporal bone resorption, otorrhea and hearing loss, and occasionally various other complications. Cholesteatoma is characterized by the enhanced proliferation of epithelial cells with aberrant morphologic characteristics. Unfortunately, our understanding of the mechanism underlying its pathogenesis is limited. To investigate its pathogenesis, different animal models have been used. This paper provides a brief overview of the current status of research in the field of pathogenesis of middle ear acquired cholesteatoma, four types of animal models previously reported on, up-to-date cholesteatoma research using these animal models, our current studies of the local hybrid ear model, and the future prospect of new animal models of middle ear cholesteatoma. PMID:21541229

Ear Infection in Isolated Cleft Lip: Etiological Implications

PubMed Central

Ruegg, Teresa A.; Cooper, Margaret E.; Leslie, Elizabeth J.; Ford, Matthew D.; Wehby, George L.; Deleyiannis, Frederic W.B.; Czeizel, Andrew E.; Hecht, Jacqueline T.; Marazita, Mary L.; Weinberg, Seth M.

2015-01-01

Background and Hypothesis Chronic ear infections are a common occurrence in children with orofacial clefts involving the secondary palate. Less is known about the middle ear status of individuals with isolated clefts of the lip, although several studies have reported elevated rates of ear infection in this group. The purpose of this retrospective study was to test the hypothesis that chronic ear infections occur more frequently in isolated cleft lip cases (n=94) compared with controls (n=183). Methods A questionnaire was used to obtain information on history of chronic ear infection. The association between ear infection status (present/absent) and cleft lip status (cleft lip case/control) was tested using both chi-square and logistic regression. Results and Conclusions The reported occurrence of chronic ear infection was significantly greater in cleft lipcases (31%) compared to unaffected controls (11%). After adjusting for age and sex, having a cleft lip increased the odds of being positive for ear infection by a factor greater than three (OR=3.698; 95%CI=1.91–7.14). Within cleft lipcases, there was no difference in the occurrence of ear infection by defect laterality or by the type of clefting present in the family history. Although velopharyngeal insufficiency was present in 18.4% of our cleft lip sample, there was no statistical association between ear infection and abnormal speech patterns. These results may have potential implications both for the clinical management of isolated cleft lip cases and for understanding the etiology of orofacial clefting. PMID:26153759

Ear Infection in Isolated Cleft Lip: Etiological Implications.

PubMed

Ruegg, Teresa A; Cooper, Margaret E; Leslie, Elizabeth J; Ford, Matthew D; Wehby, George L; Deleyiannis, Frederic W B; Czeizel, Andrew E; Hecht, Jacqueline T; Marazita, Mary L; Weinberg, Seth M

2017-03-01

  Chronic ear infections are a common occurrence in children with orofacial clefts involving the secondary palate. Less is known about the middle ear status of individuals with isolated clefts of the lip, although several studies have reported elevated rates of ear infection in this group. The purpose of this retrospective study was to test the hypothesis that chronic ear infections occur more frequently in isolated cleft lip cases (n = 94) compared with controls (n = 183).   A questionnaire was used to obtain information on history of chronic ear infection. The association between ear infection status (present/absent) and cleft lip status (cleft lip case/control) was tested using both chi-square and logistic regression.   The reported occurrence of chronic ear infection was significantly greater in cleft lip cases (31%) compared with unaffected controls (11%). After adjusting for age and sex, having a cleft lip increased the odds of being positive for ear infection by a factor greater than 3 (odds ratio = 3.698; 95% confidence interval = 1.91 to 7.14). Within cleft lip cases, there was no difference in the occurrence of ear infection by defect laterality or by the type of clefting present in the family history. Although velopharyngeal insufficiency was present in 18.4% of our cleft lip sample, there was no statistical association between ear infection and abnormal speech patterns. These results may have potential implications both for the clinical management of isolated cleft lip cases and for understanding the etiology of orofacial clefting.

Ear tag

MedlinePlus

... an ear tag or pit are: An inherited tendency to have this facial feature A genetic syndrome ... Elsevier Churchill Livingstone; 2016:chap 19. Review Date 4/24/2017 Updated by: Liora C Adler, MD, ...

Ear Infections

MedlinePlus

... but they are less common. The infection usually affects the middle ear and is called otitis media. ... become clogged with fluid and mucus. This can affect hearing, because sound cannot get through all that ...

Ear emergencies

MedlinePlus

... and ruptured eardrums can be caused by: Inserting cotton swabs, toothpicks, pins, pens, or other objects into ... The person will have severe pain. Place sterile cotton gently in the outer ear canal to keep ...

Proteomic analysis of rainbow trout (Oncorhynchus mykiss) intestinal epithelia: physiological acclimation to short-term starvation.

PubMed

Baumgarner, Bradley L; Bharadwaj, Anant S; Inerowicz, Dorota; Goodman, Angela S; Brown, Paul B

2013-03-01

The intestinal epithelia form the first line of defense against harmful agents in the gut lumen of most monogastric vertebrates, including teleost fishes. Previous investigations into the effect of starvation on the intestinal epithelia of teleost fishes have focused primarily on changes in morphological characteristics and targeted molecular analysis of specific enzymes. The goal of this study was to use a comprehensive approach to help reveal how the intestinal epithelia of carnivorous teleost fishes acclimate to short-term nutrient deprivation. We utilized two-dimensional gel electrophoresis (2-DE) to conduct the proteomic analysis of the mucosal and epithelial layer of the anterior gut intestinal tract (GIT) from satiation fed vs. 4 week starved rainbow trout (Oncorhynchus mykiss). A total of 40 proteins were determined to be differentially expressed and were subsequently picked for in-gel trypsin digestion. Peptide mass fingerprint analysis was conducted using matrix assisted laser desorption time-of-flight/time-of-flight. Nine of the 11 positively identified proteins were directly related to innate immunity. The expression of α-1 proteinase inhibitor decreased in starved vs. fed fish. Also, the concentration of one leukocyte elastase inhibitor (LEI) isomer decreased in starved fish, though the concentration of another LEI isomer increased in due to starvation. In addition, starvation promoted an increased concentration of the important xenobiotic-transporter p-glycoprotein. Finally, starvation resulted in a significant increase in type II keratin E2. Overall, our results indicate that starvation promoted a reduced capacity to inhibit enzymatic stress but increased xenobiotic resistance and paracellular permeability of epithelial cells in the anterior intestine of rainbow trout. Copyright © 2012 Elsevier Inc. All rights reserved.

Age-Related Sensory Impairments and Risk of Cognitive Impairment.

PubMed

Fischer, Mary E; Cruickshanks, Karen J; Schubert, Carla R; Pinto, Alex A; Carlsson, Cynthia M; Klein, Barbara E K; Klein, Ronald; Tweed, Ted S

2016-10-01

To evaluate the associations between sensory impairments and 10-year risk of cognitive impairment. The Epidemiology of Hearing Loss Study (EHLS), a longitudinal, population-based study of aging in the Beaver Dam, Wisconsin community. Baseline examinations were conducted in 1993 and follow-up examinations have been conducted every 5 years. General community. EHLS members without cognitive impairment at EHLS-2 (1998-2000). There were 1,884 participants (mean age 66.7) with complete EHLS-2 sensory data and follow-up information. Cognitive impairment was defined as a Mini-Mental State Examination score of <24 or history of dementia or Alzheimer's disease. Hearing impairment was a pure-tone average of hearing thresholds (0.5, 1, 2, 4 kHz) of >25 dB hearing level in either ear, visual impairment was a Pelli-Robson contrast sensitivity of <1.55 log units in the better eye, and olfactory impairment was a San Diego Odor Identification Test score of <6. Hearing, visual, and olfactory impairment were independently associated with cognitive impairment risk (hearing: hazard ratio (HR) = 1.90, 95% confidence interval (CI) = 1.11-3.26; vision: HR = 2.05, 95% CI = 1.24-3.38; olfaction: HR = 3.92, 95% CI = 2.45-6.26)). Nevertheless, 85% of participants with hearing impairment, 81% with visual impairment, and 76% with olfactory impairment did not develop cognitive impairment during follow-up. The relationship between sensory impairment and cognitive impairment was not unique to one sensory system, suggesting that sensorineural health may be a marker of brain aging. The development of a combined sensorineurocognitive measure may be useful in uncovering mechanisms of healthy brain aging. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

Management of auricular hematoma and the cauliflower ear.

PubMed

Greywoode, Jewel D; Pribitkin, Edmund A; Krein, Howard

2010-12-01

Acute auricular hematoma is common after blunt trauma to the side of the head. A network of vessels provides a rich blood supply to the ear, and the ear cartilage receives its nutrients from the overlying perichondrium. Prompt management of hematoma includes drainage and prevention of reaccumulation. If left untreated, an auricular hematoma can result in complications such as perichondritis, infection, and necrosis. Cauliflower ear may result from long-standing loss of blood supply to the ear cartilage and formation of neocartilage from disrupted perichondrium. Management of cauliflower ear involves excision of deformed cartilage and reshaping of the auricle. © Thieme Medical Publishers.

Effects of Varieties, Producing Areas, Ears, and Ear Positions of Single Maize Kernels on Near-Infrared Spectra for Identification and Traceability.

PubMed

An, Dong; Cui, Yongjin; Liu, Xu; Jia, Shiqiang; Zheng, Shuyun; Che, Xiaoping; Liu, Zhe; Zhang, Xiaodong; Zhu, Dehai; Li, Shaoming

2016-01-01

The effects of varieties, producing areas, ears, and ear positions of maize on near-infrared (NIR) spectra were investigated to determine the factors causing the differences in NIR fingerprints of maize varieties. A total of 130 inbred lines were grown in two regions in China, and 12,350 kernel samples were analyzed through NIR spectroscopy. Spectral differences among varieties, producing areas, ears, and ear positions were determined and compared on the basis of pretreated spectra. The bands at 1300-1470, 1768-1949, 2010-2064, and 2235-2311 nm were mainly affected by the producing area. Band selection and principal component analysis were applied to improve the influence of variety on NIR spectra by processing the pretreated spectra. The degrees of the influence of varieties, producing areas, ears, and ear positions were calculated, and the percentages of the influence of varieties, producing areas, ears, and ear positions were 45.40%, 42.66%, 8.22%, and 3.72%, respectively. Therefore, genetic differences among maize inbred lines are the main factors accounted for NIR spectral differences. Producing area is a secondary factor. These results could provide a reference for researchers who authenticate varieties, perform geographical origin traceabilities, and conduct maize seed breeding.

Pierced Ears

MedlinePlus

... weeks. Then you can start enjoying your pierced ears again! Reviewed by: Steven Dowshen, MD Date reviewed: September ... All information on KidsHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, ...

Histochemical localisation of carbonic anhydrase in the inner ear of developing cichlid fish, Oreochromis mossambicus

NASA Astrophysics Data System (ADS)

Beier, M.; Hilbig, R.; Anken, R.

2008-12-01

Inner ear otolith growth in terms of mineralisation mainly depends on the enzyme carbonic anhydrase (CAH). CAH is located in specialised, mitochondria-rich macular cells (ionocytes), which are involved in the endolymphatic ion exchange, and the enzyme is responsible for the provision of the pH-value necessary for otolithic calcium carbonate deposition. In the present study, for the first time the localisation of histochemically demonstrated CAH was analysed during the early larval development of a teleost, the cichlid fish Oreochromis mossambicus. CAH-reactivity was observed already in stage 7 animals (onset of otocyst development; staging follows Anken et al. [Anken, R., Kappel, T., Slenzka, K., Rahmann, H. The early morphogenetic development of the cichlid fish, Oreochromis mossambicus (Perciformes, Teleostei). Zool. Anz. 231, 1-10, 1993]). Neuroblasts (from which sensory and supporting cells are derived) proved to be CAH-positive. Already at stage 12 (hatch), CAH-positive regions could be attributed to ionocyte containing regions both in the so-called meshwork and patches area of the macula (i.e., clearly before ionocytes can be identified on ultrastructural level or by employing immunocytochemistry). In contrast to the circumstances observed in mammalian species, sensory hair cells stained negative for CAH in the cichlid. With the onset of stage 16 (finray primordia in dorsal fin, yolk-sac being increasingly absorbed), CAH-reactivity was observed in the vestibular nerve. This indicates the onset of myelinisation and thus commencement of operation. The localisation of CAH in the inner ear of fish (especially the differences in comparison to mammals) is discussed on the basis of its role in otolith calcification. Since the vestibular system is a detector of acceleration and thus gravity, also aspects regarding effects of altered gravity on CAH and hence on the mineralisation of otoliths in an adaptive process are addressed.

Fumonisin B(1)-nonproducing strains of Fusarium verticillioides cause maize (Zea mays) ear infection and ear rot.

PubMed

Desjardins, A E; Plattner, R D

2000-11-01

Fumonisins are polyketide mycotoxins produced by Fusarium verticillioides (synonym F. moniliforme), a major pathogen of maize (Zea mays) worldwide. Most field strains produce high levels of fumonisin B(1) (FB(1)) and low levels of the less-oxygenated homologues FB(2) and FB(3), but fumonisin B(1)-nonproducing field strains have been obtained by natural variation. To test the role of various fumonisins in pathogenesis on maize under field conditions, one strain producing FB(1), FB(2), and FB(3), one strain producing only FB(2), one strain producing only FB(3), and one fumonisin-nonproducing strain were applied to ears via the silk channel and on seeds at planting. Disease severity on the harvested ears was evaluated by visible symptoms and by weight percent symptomatic kernels. Fumonisin levels in kernels were determined by high-performance liquid chromatography. The presence of the applied FB(1)-nonproducing strains in kernels was determined by analysis of recovered strains for fumonisin production and other traits. All three FB(1)-nonproducing strains were able to infect ears following either silk-channel application or seed application at planting and were as effective as the FB(1)-producing strain in causing ear rot following silk-channel application. These results indicate that production of FB(1), FB(2), or FB(3) is not required for F. verticillioides to cause maize ear infection and ear rot.

Computational Modeling of Blast Wave Transmission Through Human Ear.

PubMed

Leckness, Kegan; Nakmali, Don; Gan, Rong Z

2018-03-01

Hearing loss has become the most common disability among veterans. Understanding how blast waves propagate through the human ear is a necessary step in the development of effective hearing protection devices (HPDs). This article presents the first 3D finite element (FE) model of the human ear to simulate blast wave transmission through the ear. The 3D FE model of the human ear consisting of the ear canal, tympanic membrane, ossicular chain, and middle ear cavity was imported into ANSYS Workbench for coupled fluid-structure interaction analysis in the time domain. Blast pressure waveforms recorded external to the ear in human cadaver temporal bone tests were applied at the entrance of the ear canal in the model. The pressure waveforms near the tympanic membrane (TM) in the canal (P1) and behind the TM in the middle ear cavity (P2) were calculated. The model-predicted results were then compared with measured P1 and P2 waveforms recorded in human cadaver ears during blast tests. Results show that the model-derived P1 waveforms were in an agreement with the experimentally recorded waveforms with statistic Kurtosis analysis. The FE model will be used for the evaluation of HPDs in future studies.

Anthropometric growth study of the ear in a Chinese population.

PubMed

Zhao, Shichun; Li, Dianguo; Liu, Zhenzhong; Wang, Yibiao; Liu, Lei; Jiang, Duyin; Pan, Bo

2018-04-01

A large number of anthropometric studies of the auricle have been reported in different nations, but little data were available in the Chinese population. The aim of this study was to analyze growth changes in the ear by measuring the width and length of ears in a Chinese population. A total of 480 participants were enrolled and classified into 1-, 3-, 5-, 7-, 9-, 12-, 14-, and 18-year groups (half were boys and half were girls in each group). Ear length, ear width, body weight, and body length were measured and recorded; ear index was calculated according to ear length and ear width. The growth of auricle and differences between genders were analyzed. Growth of ear in relation to body height and weight and the degree of emphasis on the length and width of the auricle were also analyzed. Ear length and width increased with age. Ear length achieved its mature size in both 14-year-old males and females. Ear width reached its mature size in males at 7 years and in females at 5 years. Different trends of ear index were shown between males and females. People in this population paid more attention to the length than the width of the auricle. The data indicated that ear development followed increase in age. There were gender and ethnic difference in the development of ear. These results may have potential implications for the diagnosis of congenital malformations, syndromes, and planning of ear reconstruction surgery. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Musical ear syndrome in adult cochlear implant patients.

PubMed

Low, W-K; Tham, C A; D'Souza, V-D; Teng, S-W

2013-09-01

Except for a single case report, musical ear syndrome in cochlear implantees has not been studied. We aimed to study the prevalence and nature of musical ear syndrome among adult cochlear implant patients, as well as the effect on their emotional well-being. STUDY DESIGN, PATIENTS AND INTERVENTION: A cross-sectional survey of patients aged 18 years and above who had received cochlear implants for profound hearing loss between 1997 and 2010. Of the 82 patients studied, 18 (22 per cent) were found to have experienced musical ear syndrome. Seven and 11 patients had musical ear syndrome prior to and after cochlear implantation, respectively. The character of musical ear syndrome symptoms was described as instrumental music (n = 2), singing (6) or both (10). Fourteen patients reported an adverse emotional effect, with three expressing ‘intolerance’. In this study, 22 per cent of cochlear implantees experienced musical ear syndrome. These symptoms affected patients’ emotional state, but most coped well. Musical ear syndrome can occur prior to and after cochlear implantation.

[Adaptability of sweet corn ears to a frozen process].

PubMed

Ramírez Matheus, Alejandra O; Martínez, Norelkys Maribel; de Bertorelli, Ligia O; De Venanzi, Frank

2004-12-01

The effects of frozen condition on the quality of three sweet corn ears (2038, 2010, 2004) and the pattern (Bonanza), were evaluated. Biometrics characteristics like ear size, ear diameter, row and kernel deep were measured as well as chemical and physical measurement in fresh and frozen states. The corn ears were frozen at -95 degrees C by 7 minutes. The yield and stability of the frozen ears were evaluated at 45 and 90 days of frozen storage (-18 degrees C). The average commercial yield as frozen corn ear for all the hybrids was 54.2%. The industry has a similar value range of 48% to 54%. The ear size average was 21.57 cm, row number was 15, ear diameter 45.54 mm and the kernel corn deep was 8.57 mm. All these measurements were found not different from commercial values found for the industry. All corn samples evaluated showed good stability despites the frozen processing and storage. Hybrid 2038 ranked higher in quality.

Distortion product otoacoustic emissions upon ear canal pressurization.

PubMed

Zebian, Makram; Schirkonyer, Volker; Hensel, Johannes; Vollbort, Sven; Fedtke, Thomas; Janssen, Thomas

2013-04-01

The purpose of this study was to quantify the change in distortion product otoacoustic emission (DPOAE) level upon ear canal pressurization. DPOAEs were measured on 12 normal-hearing human subjects for ear canal static pressures between -200 and +200 daPa in (50 ± 5) daPa steps. A clear dependence of DPOAE levels on the pressure was observed, with levels being highest at the maximum compliance of the middle ear, and decreasing on average by 2.3 dB per 50 daPa for lower and higher pressures. Ear canal pressurization can serve as a tool for improving the detectability of DPOAEs in the case of middle-ear dysfunction.

Piezo- and Flexoelectric Membrane Materials Underlie Fast Biological Motors in the Ear

PubMed Central

Breneman, Kathryn D.; Rabbitt, Richard D.

2010-01-01

The mammalian inner ear is remarkably sensitive to quiet sounds, exhibits over 100dB dynamic range, and has the exquisite ability to discriminate closely spaced tones even in the presence of noise. This performance is achieved, in part, through active mechanical amplification of vibrations by sensory hair cells within the inner ear. All hair cells are endowed with a bundle of motile microvilli, stereocilia, located at the apical end of the cell, and the more specialized outer hair cells (OHC’s) are also endowed with somatic electromotility responsible for changes in cell length in response to perturbations in membrane potential. Both hair bundle and somatic motors are known to feed energy into the mechanical vibrations in the inner ear. The biophysical origin and relative significance of the motors remains a subject of intense research. Several biological motors have been identified in hair cells that might underlie the motor(s), including a cousin of the classical ATP driven actin-myosin motor found in skeletal muscle. Hydrolysis of ATP, however, is much too slow to be viable at audio frequencies on a cycle-by-cycle basis. Heuristically, the OHC somatic motor behaves as if the OHC lateral wall membrane were a piezoelectric material and the hair bundle motor behaves as if the plasma membrane were a flexoelectric material. We propose these observations from a continuum materials perspective are literally true. To examine this idea, we formulated mathematical models of the OHC lateral wall “piezoelectric” motor and the more ubiquitous “flexoelectric” hair bundle motor. Plausible biophysical mechanisms underlying piezo- and flexoelectricity were established. Model predictions were compared extensively to the available data. The models were then applied to study the power conversion efficiency of the motors. Results show that the material properties of the complex membranes in hair cells provide them with the ability to convert electrical power available in

Cilia and Ear.

PubMed

Piatti, Gioia; De Santi, Maria Margherita; Torretta, Sara; Pignataro, Lorenzo; Soi, Daniela; Ambrosetti, Umberto

2017-04-01

To investigate the prevalence of otological complications derived from primary ciliary dyskinesia (PCD) in adulthood. Twenty-three patients with diagnosed PCD underwent medical history aimed at recording the presence of ear, nose, and throat manifestations (ENT) and any surgical treatments. The ENT objectivity was annotated, and then patients were subjected to audiometric test, tympanometry, registration of otoacoustic emission, and vestibular evaluation. Otitis media with chronic middle ear effusion (OME) during childhood was reported in 52% of the subjects, no patient had undergone ear surgery, and only 2 patients had an episode of otitis in the last year. Eleven of 23 patients showed normal hearing, 11 had a conductive hearing impairment, and 1 showed a severe sensorineural hearing loss unrelated to the syndrome. The bilateral stapedial reflex was only found in all cases of normoacusia and type A tympanogram, distortion product otoacoustic emissions (DPOAE) were present in 8 patients, and no patient had vestibular alterations. Our study confirms a very frequent prevalence of OME in PCD during childhood. Careful monitoring of otological complications of the syndrome is always desirable, also given the high presence in adults of other manifestations in the upper airways, such as chronic rhinosinusitis and nasal polyposis.

Why Internally Coupled Ears (ICE) Work Well

NASA Astrophysics Data System (ADS)

van Hemmen, J. Leo

2014-03-01

Many vertebrates, such as frogs and lizards, have an air-filled cavity between left and right eardrum, i.e., internally coupled ears (ICE). Depending on source direction, internal time (iTD) and level (iLD) difference as experienced by the animal's auditory system may greatly exceed [C. Vossen et al., JASA 128 (2010) 909-918] the external, or interaural, time and level difference (ITD and ILD). Sensory processing only encodes iTD and iLD. We present an extension of ICE theory so as to elucidate the underlying physics. First, the membrane properties of the eardrum explain why for low frequencies iTD dominates whereas iLD does so for higher frequencies. Second, the plateau of iTD = γ ITD for constant 1 < γ < 5 and variable input frequency <ν∘ follows; e.g., for the Tockay gecko ν∘ ~ 1 . 5 kHz. Third, we use a sectorial instead of circular membrane to quantify the effect of the extracolumella embedded in the tympanum and connecting with the cochlea. The main parameters can be adjusted so that the model is species independent. Work done in collaboration with A.P. Vedurmudi and J. Goulet; partially supported by BCCN-Munich.

Wood combustion particles induce adverse effects to normal and diseased airway epithelia.

PubMed

Krapf, Manuel; Künzi, Lisa; Allenbach, Sandrine; Bruns, Emily A; Gavarini, Ilaria; El-Haddad, Imad; Slowik, Jay G; Prévôt, André S H; Drinovec, Luka; Močnik, Griša; Dümbgen, Lutz; Salathe, Matthias; Baumlin, Nathalie; Sioutas, Constantinos; Baltensperger, Urs; Dommen, Josef; Geiser, Marianne

2017-04-19

Residential wood burning is a major source of poorly characterized, deleterious particulate matter, whose composition and toxicity may vary with wood type, burning condition and photochemical age. The causative link between ambient wood particle constituents and observed adverse health effects is currently lacking. Here we investigate the relationship between chemical properties of primary and atmospherically aged wood combustion particles and acute toxicity in human airway epithelial cells. Emissions from a log wood burner were diluted and injected into a smog chamber for photochemical aging. After concentration-enrichment and removal of oxidizing gases, directly emitted and atmospherically aged particles were deposited on cell cultures at the air-liquid interface for 2 hours in an aerosol deposition chamber mimicking physiological conditions in lungs. Cell models were fully differentiated normal and diseased (cystic fibrosis and asthma) human bronchial epithelia (HBE) and the bronchial epithelial cell line BEAS-2B. Cell responses were assessed at 24 hours after aerosol exposure. Atmospherically relevant doses of wood combustion particles significantly increased cell death in all but the asthma cell model. Expression of oxidative stress markers increased in HBE from all donors. Increased cell death and inflammatory responses could not be assigned to a single chemical fraction of the particles. Exposure to primary and aged wood combustion particles caused adverse effects to airway epithelia, apparently induced by several interacting components.

Daple coordinates organ-wide and cell-intrinsic polarity to pattern inner-ear hair bundles

PubMed Central

Siletti, Kimberly; Hudspeth, A. J.

2017-01-01

The establishment of planar polarization by mammalian cells necessitates the integration of diverse signaling pathways. In the inner ear, at least two systems regulate the planar polarity of sensory hair bundles. The core planar cell polarity (PCP) proteins coordinate the orientations of hair cells across the epithelial plane. The cell-intrinsic patterning of hair bundles is implemented independently by the G protein complex classically known for orienting the mitotic spindle. Although the primary cilium also participates in each of these pathways, its role and the integration of the two systems are poorly understood. We show that Dishevelled-associating protein with a high frequency of leucine residues (Daple) interacts with PCP and cell-intrinsic signals. Regulated by the cell-intrinsic pathway, Daple is required to maintain the polarized distribution of the core PCP protein Dishevelled and to position the primary cilium at the abneural edge of the apical surface. Our results suggest that the primary cilium or an associated structure influences the domain of cell-intrinsic signals that shape the hair bundle. Daple is therefore essential to orient and pattern sensory hair bundles. PMID:29229865

Sheep as a large animal ear model: Middle-ear ossicular velocities and intracochlear sound pressure.

PubMed

Péus, Dominik; Dobrev, Ivo; Prochazka, Lukas; Thoele, Konrad; Dalbert, Adrian; Boss, Andreas; Newcomb, Nicolas; Probst, Rudolf; Röösli, Christof; Sim, Jae Hoon; Huber, Alexander; Pfiffner, Flurin

2017-08-01

Animals are frequently used for the development and testing of new hearing devices. Dimensions of the middle ear and cochlea differ significantly between humans and commonly used animals, such as rodents or cats. The sheep cochlea is anatomically more like the human cochlea in size and number of turns. This study investigated the middle-ear ossicular velocities and intracochlear sound pressure (ICSP) in sheep temporal bones, with the aim of characterizing the sheep as an experimental model for implantable hearing devices. Measurements were made on fresh sheep temporal bones. Velocity responses of the middle ear ossicles at the umbo, long process of the incus and stapes footplate were measured in the frequency range of 0.25-8 kHz using a laser Doppler vibrometer system. Results were normalized by the corresponding sound pressure level in the external ear canal (P EC ). Sequentially, ICSPs at the scala vestibuli and tympani were then recorded with custom MEMS-based hydrophones, while presenting identical acoustic stimuli. The sheep middle ear transmitted most effectively around 4.8 kHz, with a maximum stapes velocity of 0.2 mm/s/Pa. At the same frequency, the ICSP measurements in the scala vestibuli and tympani showed the maximum gain relative to the P EC (24 dB and 5 dB, respectively). The greatest pressure difference across the cochlear partition occurred between 4 and 6 kHz. A comparison between the results of this study and human reference data showed middle-ear resonance and best cochlear sensitivity at higher frequencies in sheep. In summary, sheep can be an appropriate large animal model for research and development of implantable hearing devices. Copyright © 2017 Elsevier B.V. All rights reserved.

Predicting skin deficits through surface area measurements in ear reconstruction and adult ear surface area norms.

PubMed

Yazar, Memet; Sevim, Kamuran Zeynep; Irmak, Fatih; Yazar, Sevgi Kurt; Yeşilada, Ayşin Karasoy; Karşidağğ, Semra Hacikerim; Tatlidede, Hamit Soner

2013-07-01

Ear reconstruction is one of the most challenging procedures in plastic surgery practice. Many studies and techniques have been described in the literature for carving a well-pronounced framework. However, just as important as the cartilage framework is the ample amount of delicate skin coverage of the framework. In this report, we introduce an innovative method of measuring the skin surface area of the auricle from a three-dimensional template created from the healthy ear.The study group consisted of 60 adult Turkish individuals who were randomly selected (30 men and 30 women). The participant ages ranged from 18 to 45 years (mean, 31.5 years), and they had no history of trauma or congenital anomalies. The template is created by dividing the ear into aesthetic subunits and using ImageJ software to estimate the necessary amount of total skin surface area required.Reconstruction of the auricle is a complicated process that requires experience and patience to provide the auricular details. We believe this estimate will shorten the learning curve for residents and surgeons interested in ear reconstruction and will help surgeons obtain adequate skin to drape over the well-sculpted cartilage frameworks by providing a reference list of total ear skin surface area measurements for Turkish men and women.

Middle ear infection (otitis media) (image)

MedlinePlus

Otitis media is an inflammation or infection of the middle ear. Acute otitis media (acute ear infection) occurs when there is ... which causes production of fluid or pus. Chronic otitis media occurs when the eustachian tube becomes blocked ...

Alternative splicing of inner-ear-expressed genes.

PubMed

Wang, Yanfei; Liu, Yueyue; Nie, Hongyun; Ma, Xin; Xu, Zhigang

2016-09-01

Alternative splicing plays a fundamental role in the development and physiological function of the inner ear. Inner-ear-specific gene splicing is necessary to establish the identity and maintain the function of the inner ear. For example, exon 68 of Cadherin 23 (Cdh23) gene is subject to inner-ear-specific alternative splicing, and as a result, Cdh23(+ 68) is only expressed in inner ear hair cells. Alternative splicing along the tonotopic axis of the cochlea contributes to frequency tuning, particularly in lower vertebrates, such as chickens and turtles. Differential splicing of Kcnma1, which encodes for the α subunit of the Ca(2+)-activated K(+) channel (BK channel), has been suggested to affect the channel gating properties and is important for frequency tuning. Consequently, deficits in alternative splicing have been shown to cause hearing loss, as we can observe in Bronx Waltzer (bv) mice and Sfswap mutant mice. Despite the advances in this field, the regulation of alternative splicing in the inner ear remains elusive. Further investigation is also needed to clarify the mechanism of hearing loss caused by alternative splicing deficits.

Forgotten T-tube in the middle ear.

PubMed

Shakeel, Muhammad; Trinidade, Aaron; Khan, Imran; Ah-See, Kim Wong

2012-05-01

Retention within the middle ear cleft is an unusual complication of T-tube insertion. A 40-year-old woman with Kartagener's Syndrome presented with hearing impairment in the right ear. She was found to have a previously inserted Goode T-tube lying within the middle ear behind an intact drum. She underwent successful removal of the T-tube via a myringotomy, and a new tube was re-inserted. Migration of a T-tube into the middle ear cleft should always be kept in mind in patients who present with otological symptoms and have a history of T-tube insertion, even in the presence of an intact drum.

Swimmer's ear

MedlinePlus

... often gets better with the proper treatment. Possible Complications The infection may spread to other areas around the ear, including the skull bone. In older people or those who have diabetes, the infection may become severe. This condition is ...

EARS: Electronic Access to Reference Service.

PubMed

Weise, F O; Borgendale, M

1986-10-01

Electronic Access to Reference Service (EARS) is a front end to the Health Sciences Library's electronic mail system, with links to the online public catalog. EARS, which became operational in September 1984, is accessed by users at remote sites with either a terminal or microcomputer. It is menu-driven, allowing users to request: a computerized literature search, reference information, a photocopy of a journal article, or a book. This paper traces the history of EARS and discusses its use, its impact on library staff and services, and factors that influence the diffusion of new technology.

Pinnaplasty: reshaping ears to improve hearing aid retention.

PubMed

Gault, David; Grob, Marion; Odili, Joy

2007-01-01

The hearing aid is extremely important to the deaf. A small number have difficulty in retaining the device because the ear is prominent or cup-shaped. This report describes 11 children whose ear shape was modified to improve hearing aid retention and one adult in whom an over set back ear was released to allow fitment of a postaural device. In eight of the 11 children treated, conservative measures such as double-sided tape and retention bands (Huggies) had been tried previously without success. The creation of an antihelical fold in a misshapen ear lacking such a fold provides a reinforcing strut which is useful to support a hearing aid. In patients whose ear had been excessively tethered by previous surgery, projection was restored by inserting a cartilage block behind the ear. In one child with ears tethered by previous surgery, costal cartilage was used not only to release both ears, but also to reconstruct a new helical rim on one side. Surgery enabled a normal postaural hearing aid to be worn in 17 of the 19 ears treated. The two failures deserve special mention. In one patient with a unilateral deformity and severe mental retardation, the dressings were pulled off immediately after surgery. In another patient with a bilateral problem, the appearance and hearing aid retention was improved, but there was not enough room in the postauricular sulcus on one side for the battery component to fit comfortably and an in-the-ear device is now used on that side. Pinnaplasty is a helpful strategy to improve hearing aid retention. Care must be taken not to overdo the set back so that enough room is left to retain the hearing device.

Physiological artifacts in scalp EEG and ear-EEG.

PubMed

Kappel, Simon L; Looney, David; Mandic, Danilo P; Kidmose, Preben

2017-08-11

A problem inherent to recording EEG is the interference arising from noise and artifacts. While in a laboratory environment, artifacts and interference can, to a large extent, be avoided or controlled, in real-life scenarios this is a challenge. Ear-EEG is a concept where EEG is acquired from electrodes in the ear. We present a characterization of physiological artifacts generated in a controlled environment for nine subjects. The influence of the artifacts was quantified in terms of the signal-to-noise ratio (SNR) deterioration of the auditory steady-state response. Alpha band modulation was also studied in an open/closed eyes paradigm. Artifacts related to jaw muscle contractions were present all over the scalp and in the ear, with the highest SNR deteriorations in the gamma band. The SNR deterioration for jaw artifacts were in general higher in the ear compared to the scalp. Whereas eye-blinking did not influence the SNR in the ear, it was significant for all groups of scalps electrodes in the delta and theta bands. Eye movements resulted in statistical significant SNR deterioration in both frontal, temporal and ear electrodes. Recordings of alpha band modulation showed increased power and coherence of the EEG for ear and scalp electrodes in the closed-eyes periods. Ear-EEG is a method developed for unobtrusive and discreet recording over long periods of time and in real-life environments. This study investigated the influence of the most important types of physiological artifacts, and demonstrated that spontaneous activity, in terms of alpha band oscillations, could be recorded from the ear-EEG platform. In its present form ear-EEG was more prone to jaw related artifacts and less prone to eye-blinking artifacts compared to state-of-the-art scalp based systems.

Use of the 'real-ear to dial difference' to derive real-ear SPL from hearing level obtained with insert earphones.

PubMed

Munro, K J; Lazenby, A

2001-10-01

The electroacoustic characteristics of a hearing instrument are normally selected for individuals using data obtained during audiological assessment. The precise inter-relationship between the electroacoustic and audiometric variables is most readily appreciated when they have been measured at the same reference point, such as the tympanic membrane. However, it is not always possible to obtain the real-ear sound pressure level (SPL) directly if this is below the noise floor of the probe-tube microphone system or if the subject is unco-operative. The real-ear SPL may be derived by adding the subject's real-ear to dial difference (REDD) acoustic transform to the audiometer dial setting. The aim of the present study was to confirm the validity of the Audioscan RM500 to measure the REDD with the ER-3A insert earphone. A probe-tube microphone was used to measure the real-ear SPL and REDD from the right ears of 16 adult subjects ranging in age from 22 to 41 years (mean age 27 years). Measurements were made from 0.25 kHz to 6 kHz at a dial setting of 70 dB with an ER-3A insert earphone and two earmould configurations: the EAR-LINK foam ear-tip and the subjects' customized skeleton earmoulds. Mean REDD varied as a function of frequency but was typically approximately 12 dB with a standard deviation (SD) of +/- 1.7 dB and +/- 2.7 dB for the foam ear-tip and customized earmould, respectively. The mean test-retest difference of the REDD varied with frequency but was typically 0.5 dB (SD 1 dB). Over the frequency range 0.5-4 kHz, the derived values were found to be within 5 dB of the measured values in 95% of subjects when using the EAR-LINK foam ear-tip and within 4 dB when using the skeleton earmould. The individually measured REDD transform can be used in clinical practice to derive a valid estimate of real-ear SPL when it has not been possible to measure this directly.

Structures that Contribute to Middle-Ear Admittance in Chinchilla

PubMed Central

Rosowski, John J.; Ravicz, Michael E.; Songer, Jocelyn E.

2009-01-01

We describe measurements of middle-ear input admittance in chinchillas (Chinchilla lanigera) before and after various manipulations that define the contributions of different middle-ear components to function. The chinchilla’s middle-ear air spaces have a large effect on the low-frequency compliance of the middle ear, and removing the influences of these spaces reveals a highly admittant tympanic membrane and ossicular chain. Measurements of the admittance of the air spaces reveal that the high-degree of segmentation of these spaces has only a small effect on the admittance. Draining the cochlea further increases the middle-ear admittance at low frequencies and removes a low-frequency (less than 300 Hz) level dependence in the admittance. Spontaneous or sound-driven contractions of the middle-ear muscles in deeply anesthetized animals were associated with significant changes in middle-ear admittance. PMID:16944166

Cauliflower Ear and Skin Infections among Wrestlers in Tehran.

PubMed

Kordi, Ramin; Mansournia, Mohammad Ali; Nourian, Roh Allah; Wallace, W Angus

2007-01-01

The purpose of the study was to describe the magnitude of the selected sports medicine problems (i.e. cauliflower ear and skin infections) among wrestlers in Tehran. A number of 411 wrestlers were randomly selected from wrestling clubs in Tehran employing cluster sample setting method. The participants were interviewed using a specially designed and validated questionnaire. Nearly half of the participants (44%) had "cauliflower ears". Only 23% of these participants had received any kind of treatment for their acute ear haematomas that are known to result in "cauliflower ears". The prevalence of reported hearing loss among participants with cauliflower ears (11.5%, 95%CI: 6.9 to 16.2) was significantly more than this prevalence among those participants without cauliflower ears (1.8%, 95%CI: 0.1 to 3.5) (p < 0.05). More than half of the participants (52%) had skin infection diagnosed by a physician during the previous year. This study has identified evidence of an increase in hearing loss as a possible side effect of either cauliflower ear or ear injury in wrestling in Iran. There has been an outbreak of ringworm and there is a significant potential for an outbreak of impetigo among wrestlers in Tehran. Key pointsSkin infections are prevalent among wrestlers in Tehran.Commonly wrestlers in Tehran continue to carry out wrestling training while affected by skin infections.Cauliflower ear "is common among wrestlers in Tehran.More research is needed to investigate hearing loss as a possible side effect of either cauliflower ear or ear injury in wrestling in Iran.

Knowledge, Attitude and Practice of Ear Care in Coastal Karnataka.

PubMed

Dosemane, Deviprasad; Ganapathi, Keerthan; Kanthila, Jayashree

2015-12-01

Ear as an organ is necessary for the perception of sound and body balance. Ear infection, diabetes mellitus, hypertension and excessive use of mobile phone for listening to music at high volume all can reduce hearing. No earlier study was available in the costal Karnataka population, regarding the practice of ear care. The study objective was to ascertain the level of knowledge of the community regarding ear care, to find out whether some of the common conditions affecting hearing are known and to find out the common practices involved in maintaining ear hygiene. This cross-sectional study was conducted on 500 subjects in two tertiary care hospitals by convenient sampling, using self-administered questionnaire. Knowledge, Attitude and Practice across the age groups, religion & education background were studied. Across different education groups, 66.7%-90% did not know that 'cold' can cause ear infection and 46.7%-75.0% did not know that diabetes and hypertension can reduce hearing. When there is ear pain or discharge, people put ear drops available at home in 48.3%-75.0% across 3 age groups; 58.5%-61.5% across 3 religions and 44.8%-67.9% across 5 education groups. No statistically significant difference was found in the practice of pouring oil into ears across religions. A total of 58.6%-100% daily clean inside the ear and 70-100% use cotton buds. General perception of the people is that ear is necessary only for hearing. Majority did not know that nasal infection can affect the ear and that DM and hypertension can cause hearing loss. When there is ear pain and discharge, most of the adults put drops that are available at home. Pouring oil into the ears and cleaning inside the ear canals is routinely practiced in costal Karnataka.

Major evolutionary transitions and innovations: the tympanic middle ear

PubMed Central

2017-01-01

One of the most amazing transitions and innovations during the evolution of mammals was the formation of a novel jaw joint and the incorporation of the original jaw joint into the middle ear to create the unique mammalian three bone/ossicle ear. In this review, we look at the key steps that led to this change and other unusual features of the middle ear and how developmental biology has been providing an understanding of the mechanisms involved. This starts with an overview of the tympanic (air-filled) middle ear, and how the ear drum (tympanic membrane) and the cavity itself form during development in amniotes. This is followed by an investigation of how the ear is connected to the pharynx and the relationship of the ear to the bony bulla in which it sits. Finally, the novel mammalian jaw joint and versatile dentary bone will be discussed with respect to evolution of the mammalian middle ear. This article is part of the themed issue ‘Evo-devo in the genomics era, and the origins of morphological diversity’. PMID:27994124

Identifying position, visibility, dimensions, and angulation of the ear.

PubMed

Mohamed, Kasim; Christian, Jayanth; Jeyapalan, Karthigeyan; Natarajan, Shanmuganathan; Banu, Fathima; Veeravalli, Padmanabhan T

2014-01-01

We selected 254 subjects between the ages of 18 and 30 yr to assess the ear position, angulations of the ear in relation to the nose, visibility from the frontal view, and dimensions of the ear by using various anthropometric points of the face. Subjects were divided into four groups based on facial form. A reference plane indicator, facial topographical measurements, metal ruler, and digital photography were used. While considering the position of the ear, in all facial forms except square tapering, the most samples showed a tendency for the subaurale being in line with subnasale. Regression analysis showed a tendency to gnathion distance is the most dependent variable with length of the ear kept as a constant predictor, while both interalar distance and exocanthion to endocanthion distance correlate highly significantly to the width of the ear. In all subjects, the visibility of the ear when viewed from the front was an average of 1.5 mm. Regardless of facial form, ear angulation was generally less than nose angulation.

Expression pattern of adhesion molecules in junctional epithelium differs from that in other gingival epithelia.

PubMed

Hatakeyama, S; Yaegashi, T; Oikawa, Y; Fujiwara, H; Mikami, T; Takeda, Y; Satoh, M

2006-08-01

The gingival epithelium is the physiologically important interface between the bacterially colonized gingival sulcus and periodontal soft and mineralized connective tissues, requiring protection from exposure to bacteria and their products. However, of the three epithelia comprising the gingival epithelium, the junctional epithelium has much wider intercellular spaces than the sulcular epithelium and oral gingival epithelium. Hence, the aim of the present study was to characterize the cell adhesion structure in the junctional epithelium compared with the other two epithelia. Gingival epithelia excised at therapeutic flap surgery from patients with periodontitis were examined for expression of adhesion molecules by immunofluorescence. In the oral gingival epithelium and sulcular epithelium, but not in the junctional epithelium, desmoglein 1 and 2 in cell-cell contact sites were more abundant in the upper than the suprabasal layers. E-cadherin, the main transmembranous molecule of adherens junctions, was present in spinous layers of the oral gingival epithelium and sulcular epithelium, but was scarce in the junctional epithelium. In contrast, desmoglein 3 and P-cadherin were present in all layers of the junctional epithelium as well as the oral gingival epithelium and sulcular epithelium. Connexin 43 was clearly localized to spinous layers of the oral gingival epithelium, sulcular epithelium and parts of the junctional epithelium. Claudin-1 and occludin were expressed in the cell membranes of a few superficial layers of the oral gingival epithelium. These findings indicated that the junctional epithelium contains only a few desmosomes, composed of only desmoglein 3; adherens junctions are probably absent because of defective E-cadherin. Thus, the anchoring junctions connecting junctional epithelium cells are lax, causing widened intercellular spaces. In contrast, the oral gingival epithelium, which has a few tight junctions, functions as a barrier.

Nonsurgical correction of congenital ear abnormalities in the newborn: Case series.

PubMed

Smith, Wg; Toye, Jw; Reid, A; Smith, Rw

2005-07-01

To determine whether a simple, nonsurgical treatment for congenital ear abnormalities (lop-ear, Stahl's ear, protruding ear, cryptotia) improved the appearance of ear abnormalities in newborns at six weeks of age. This is a descriptive case series. All newborns with identified abnormalities were referred by their family physician to one paediatrician (WGS) in a small level 2 perinatal centre. The ears were waxed and taped in a standard manner within 10 days of birth. Pictures were taken before taping and at the end of taping (one month). All patients and pictures were assessed by one plastic surgeon (JWT) at six weeks of age and scored using a standard scoring system. A telephone survey of the nontreatment group was conducted. The total number of ears assessed was 90. Of this total, 69 ears were taped and fully evaluated in the study (77%). The refusal rate was 23%. In the treatment group, 59% had lop-ear, 19% had Stahl's ear, 17% had protruding ear and 3% had cryptotia. Overall correction (excellent/improved) for the treatment group was 90% (100% for lop-ear, 100% for Stahl's ear, 67% for protruding ear and 0% for cryptotia). In the nontreatment (refusal) group, 67% of the ears failed to correct spontaneously. No complications were recognized by the authors or parents by six weeks. The percentage of newborns in one year in the perinatal centre with recognized ear abnormalities was 6% (90 of 1600). A simple, nonsurgical treatment in a Caucasian population appeared to be very effective in correcting congenital ear abnormalities with no complications and high patient/parent satisfaction.

[Expression and clinical significance of Xiap and Caspase-3 protien in primary epithelia ovarian cancer].

PubMed

Chen, Wei; Peng, Ping

2010-07-01

To study the expression and clinical significance of Xiap, Caspase-3 protein in primary epithelia ovarian cancer. The Xiap and Caspase-3 were detected by immunohistochemical in 40 cases of epithelial ovarian cancer 20 cases of borderline ovarian tumor, 15 cases of benign ovarian tumor, and 15 normal ovarian tissues. There were significantly different between the expression of Xiap in epithelial ovarian cancer, borderline ovarian tumor, benign ovarian tumor and normal ovarian tissues. The expression of Caspase-3 in epithelial ovarian cancer and borderline ovarian tumor was significantly lower than that in benign ovarian tumor and normal ovarian tissue (P<0.01). The expression of Xiap in epithelial ovarian cancer was related to clinc stage, pathological grade and living. The expression of caspase-3 in epithelial ovarian cancer was related to clinc stage and living (P<0.01). The expressions of Xiap and Caspase-3 may be important roles for the formation and development of epithelia ovarian cancer. The expressions of Xiap and Caspase-3 are the poor prognostic factors in epithelial ovarian carcinomas.

Anomalous Brownian motion discloses viscoelasticity in the ear's mechanoelectrical-transduction apparatus.

PubMed

Kozlov, Andrei S; Andor-Ardó, Daniel; Hudspeth, A J

2012-02-21

The ear detects sounds so faint that they produce only atomic-scale displacements in the mechanoelectrical transducer, yet thermal noise causes fluctuations larger by an order of magnitude. Explaining how hearing can operate when the magnitude of the noise greatly exceeds that of the signal requires an understanding both of the transducer's micromechanics and of the associated noise. Using microrheology, we characterize the statistics of this noise; exploiting the fluctuation-dissipation theorem, we determine the associated micromechanics. The statistics reveal unusual Brownian motion in which the mean square displacement increases as a fractional power of time, indicating that the mechanisms governing energy dissipation are related to those of energy storage. This anomalous scaling contradicts the canonical model of mechanoelectrical transduction, but the results can be explained if the micromechanics incorporates viscoelasticity, a salient characteristic of biopolymers. We amend the canonical model and demonstrate several consequences of viscoelasticity for sensory coding.

Neonatal Ear Molding: Timing and Technique.

PubMed

Anstadt, Erin Elizabeth; Johns, Dana Nicole; Kwok, Alvin Chi-Ming; Siddiqi, Faizi; Gociman, Barbu

2016-03-01

The incidence of auricular deformities is believed to be ∼11.5 per 10,000 births, excluding children with microtia. Although not life-threatening, auricular deformities can cause undue distress for patients and their families. Although surgical procedures have traditionally been used to reconstruct congenital auricular deformities, ear molding has been gaining acceptance as an efficacious, noninvasive alternative for the treatment of newborns with ear deformations. We present the successful correction of bilateral Stahl's ear deformity in a newborn through a straightforward, nonsurgical method implemented on the first day of life. The aim of this report is to make pediatric practitioners aware of an effective and simple molding technique appropriate for correction of congenital auricular anomalies. In addition, it stresses the importance of very early initiation of ear cartilage molding for achieving the desired outcome. Copyright © 2016 by the American Academy of Pediatrics.

[Basics of Ear Surgery].

PubMed

Lailach, S; Zahnert, T

2016-12-01

The present article about the basics of ear surgery is a short overview of current indications, the required diagnostics and surgical procedures of common otologic diseases. In addition to plastic and reconstructive surgery of the auricle, principles of surgery of the external auditory canal, basics of middle ear surgery and the tumor surgery of the temporal bone are shown. Additionally, aspects of the surgical hearing rehabilitation (excluding implantable hearing systems) are presented considering current study results. Georg Thieme Verlag KG Stuttgart · New York.

Sound-diffracting flap in the ear of a bat generates spatial information.

PubMed

Müller, Rolf; Lu, Hongwang; Buck, John R

2008-03-14

Sound diffraction by the mammalian ear generates source-direction information. We have obtained an immediate quantification of this information from numerical predictions. We demonstrate the power of our approach by showing that a small flap in a bat's pinna generates useful information over a large set of directions in a central band of frequencies: presence of the flap more than doubled the solid angle with direction information above a given threshold. From the workings of the employed information measure, the Cramér-Rao lower bound, we can explain how physical shape is linked to sensory information via a strong sidelobe with frequency-dependent orientation in the directivity pattern. This method could be applied to any other mammal species with pinnae to quantify the relative importance of pinna structures' contributions to directional information and to facilitate interspecific comparisons of pinna directivity patterns.

Milestones in the History of Ear Reconstruction.

PubMed

Berghaus, Alexander; Nicoló, Marion San

2015-12-01

The reconstruction of ear deformities has been challenging plastic surgeons since centuries. However, it is only in the 19th century that reports on partial and total ear reconstruction start increasing. In the quest for an aesthetically pleasing and natural-looking result, surgeons worked on the perfect framework and skin coverage. Different materials and flap techniques have evolved. Some were abandoned out of frustration, while others kept evolving over the years. In this article, we discuss the milestones in ear reconstruction-from ancient times to early attempts in Western civilization to the key chapters of ear reconstruction in the 20th century leading to the current techniques. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Size and Cell Number of the Utricle in kinetotically swimming Fish: A parabolic Aircraft Flight Study

NASA Astrophysics Data System (ADS)

Baeuerle, A.; Anken, R.; Baumhauer, N.; Hilbig, R.; Rahmann, H.

Humans taking part in parabolic aircraft flights (PAFs) may suffer from space motion sickness (SMS, a kinetosis). Since it has been repeatedly shown earlier that some fish of a given batch also reveal a kinetotic behaviour during PAFs (especially so-called spinning movements and looping responses), and due to the homology of the vestibular apparatus among all vertebrates, fish can be used as model systems to investigate the origin of susceptibility to motion sickness. Therefore, we examined the utricular maculae (they are responsible for the internalisation of gravity in teleosteans) of fish swimming kinetotically during the μg-phases in the course of PAFs in comparison with animals from the same batch who swam normally. On the light microscopical level, it was found that the total number of both sensory and supporting cells of the utricular maculae did not differ between kinetotic animals as compared to normally swimming fish. Cell density (sensory and supporting cells/100μm -μm), however, was reduced in kinetotic animals (p<0.0001), which seemed to be due to malformed epithelial cells (increase in cell size) of the kinetotic specimens. Susceptibility to kinetoses may therefore originate in asymmetric inner ear otoliths as has been suggested earlier, but also in genetically predispositioned, malformed sensory epithelia. This work was financially supported by the German Aerospace Center (DLR) e.V. (FKZ: 50 WB 9997).

High-throughput method for ear phenotyping and kernel weight estimation in maize using ear digital imaging.

PubMed

Makanza, R; Zaman-Allah, M; Cairns, J E; Eyre, J; Burgueño, J; Pacheco, Ángela; Diepenbrock, C; Magorokosho, C; Tarekegne, A; Olsen, M; Prasanna, B M

2018-01-01

Grain yield, ear and kernel attributes can assist to understand the performance of maize plant under different environmental conditions and can be used in the variety development process to address farmer's preferences. These parameters are however still laborious and expensive to measure. A low-cost ear digital imaging method was developed that provides estimates of ear and kernel attributes i.e., ear number and size, kernel number and size as well as kernel weight from photos of ears harvested from field trial plots. The image processing method uses a script that runs in a batch mode on ImageJ; an open source software. Kernel weight was estimated using the total kernel number derived from the number of kernels visible on the image and the average kernel size. Data showed a good agreement in terms of accuracy and precision between ground truth measurements and data generated through image processing. Broad-sense heritability of the estimated parameters was in the range or higher than that for measured grain weight. Limitation of the method for kernel weight estimation is discussed. The method developed in this work provides an opportunity to significantly reduce the cost of selection in the breeding process, especially for resource constrained crop improvement programs and can be used to learn more about the genetic bases of grain yield determinants.

Understanding the evolution and development of neurosensory transcription factors of the ear to enhance therapeutic translation

PubMed Central

Pan, Ning; Kopecky, Benjamin; Jahan, Israt; Fritzsch, Bernd

2012-01-01

Reconstructing a functional organ of Corti is the ultimate target towards curing hearing loss. Despite the impressive technical gains made over the last few years, many complications remain ahead for the two main restoration avenues: in vitro transformation of pluripotent cells into hair cell-like cells and adenovirus-mediated gene therapy. Most notably, both approaches require a more complete understanding of the molecular networks that ensure specific cell types form in the correct places to allow proper function of the restored organ of Corti. Important to this understanding are the basic helix-loop-helix (bHLH) transcription factors (TFs) that are highly diverse and serve to increase functional complexity but their evolutionary implementation in the inner ear neurosensory development is less conspicuous. To this end, we review the evolutionary and developmentally dynamic interactions of the three bHLH TFs that have been identified as the main players in neurosensory evolution and development, Neurog1, Neurod1 and Atoh1. These three TFs belong to the neurogenin/atonal family and evolved from a molecular precursor that likely regulated single sensory cell development in the ectoderm of metazoan ancestors but are now also expressed in other parts of the body, including the brain. They interact extensively via intracellular and intercellular cross-regulation to establish the two main neurosensory cell types of the ear, the hair cells and sensory neurons. Furthermore, the level and duration of their expression affect the specification of hair cell subtypes (inner hair cells vs. outer hair cells). We propose that appropriate manipulation of these TFs through their characterized binding sites may offer a solution by itself, or in conjunction with the two other approaches currently pursued by others, to restore the organ of Corti. PMID:22688958

Microgravity in the STS-29 space shuttle discovery affected the vestibular system of chick embryos

NASA Technical Reports Server (NTRS)

Fermin, C. D.; Martin, D.; Jones, T.; Vellinger, J.; Deuser, M.; Hester, P.; Hullinger, R.

1996-01-01

Out of 32 embryos flown (16 @ E2 + 16 @ E9) for 5 days, 16 survived. All sixteen E2 were dead at landing. Eight were opened and eight were incubated at 1.0G. Autopsy showed that 4 E2 survived over 24 hours in space. Eight E14 hatched without anatomical malformations, and 8 E14 were fixed. The height of the macular epithelia was 31 mu m (mean) in control and 26 mu m in flight chicks. The cross-sectional area of macular nuclei of control was 17 mu m(2) for hair cells and 14 mu m(2) in supporting cells. In flight, cross-sectional area was 17 mu m(2) in hair cells and 15 mu m(2) in supporting cells (n=250). The shape factor of cartilage cells (1.0 = perfect circle) between control (mean = 0.70) and flight (mean = 0.72), and the area of cartilaginous cells between controls (mean = 9 mu m(2)) and flight (mean = 9 mu m(2)) did not differ (n=300). The nuclei of support cells were closer to the basement membrane in flight than in control chicks. The immunoreactivity of otoconia with anti keratan, fibronectin or chrondroitin sulfate was not different between flight and control ears. There were more afferent fibers inside the macular epithelia of flight (p<0.05) than control. Three of 8 flight animals had elevated vestibular thresholds (VT), with normal mean response amplitudes and latencies. Modified afferent innervation patterns requiring weeks to compensate are sufficient to elevate VT, and should be investigated further. Other reversible (sublethal) microgravity effects on sensory epithelia (vacuoles, swelling, etc) require quantification.

EARS: Electronic Access to Reference Service.

PubMed Central

Weise, F O; Borgendale, M

1986-01-01

Electronic Access to Reference Service (EARS) is a front end to the Health Sciences Library's electronic mail system, with links to the online public catalog. EARS, which became operational in September 1984, is accessed by users at remote sites with either a terminal or microcomputer. It is menu-driven, allowing users to request: a computerized literature search, reference information, a photocopy of a journal article, or a book. This paper traces the history of EARS and discusses its use, its impact on library staff and services, and factors that influence the diffusion of new technology. PMID:3779167

A break-even analysis of major ear surgery.

PubMed

Wasson, J D; Phillips, J S

2015-10-01

To determine variables which affect cost and profit for major ear surgery and perform a break-even analysis. Retrospective financial analysis. UK teaching hospital. Patients who underwent major ear surgery under general anaesthesia performed by the senior author in main theatre over a 2-year period between dates of 07 September 2010 and 07 September 2012. Income, cost and profit for each major ear patient spell. Variables that affect major ear surgery profitability. Seventy-six patients met inclusion criteria. Wide variation in earnings, with a median net loss of £-1345.50 was observed. Income was relatively uniform across all patient spells; however, theatre time of major ear surgery at a cost of £953.24 per hour varied between patients and was the main determinant of cost and profit for the patient spell. Bivariate linear regression of earnings on theatre time identified 94% of variation in earnings was due to variation in theatre time (r = -0.969; P < 0.0001) and derived a break-even time for major ear surgery of 110.6 min. Theatre time was dependent on complexity of procedure and number of OPCS4 procedures performed, with a significant increase in theatre time when three or more procedures were performed during major ear surgery (P = 0.015). For major ear surgery to either break-even or return a profit, total theatre time should not exceed 110 min and 36 s. © 2015 John Wiley & Sons Ltd.

Organization of tubules in the human caput epididymidis and the ultrastructure of their epithelia.

PubMed

Yeung, C H; Cooper, T G; Bergmann, M; Schulze, H

1991-07-01

The structure of the human caput epididymidis was examined by gross morphological and light and electron microscopic techniques. There were at least seven types of tubules, each characterized by a different epithelium. These tubules were connected with one another by at least eight types of junctions to form a network. Most of the caput epididymidis was composed of efferent ducts. Within these, five types of tubules, each with a different ciliated epithelium, were found in different regions; and four types of junctions between the efferent ducts and the epididymal tubule were observed. The efferent ducts left the testis, initially as parallel straight tubules containing both ciliated and non-ciliated cells in an epithelium of irregular height. Each efferent duct then coiled tortuously into lobules that folded over one another. These efferent ducts then branched out as thin tubules to join a network of dark tubules which were lined by a regular epithelium containing prominently vacuolated, non-ciliated cells. These tubules anastomosed via common cavities characterized by a ciliated cuboidal epithelium and sometimes joined tubules exhibiting a non-vacuolated ciliated epithelium. The latter, as well as typical efferent ducts, made connection with the epididymis proper in both end-to-end and end-to-side junctions. In the more distal junctions with the epididymis, the efferent ducts joined to a transitional epididymal ductule before joining to the side of the epididymis proper. Post-junctional epithelia in the beginning of the epididymis occasionally contained patches of cells characteristic of efferent ducts. Tall cells with long stereocilia constituted a discontinuous "initial segment"-like region of the epididymis. This is the most detailed study so far of the epithelia and the tubule organization in the caput epididymidis of any species, and most of the results are reported for the first time for the human. Although the pattern of the tubule network resembles that

Middle Ear Pressures in Wind Instrument Musicians.

PubMed

Osborne, Max Sallis; Morris, Simon; Clark, Matthew P; Begg, Philip

2018-05-22

This study aimed to assess if playing wind instruments leads to a measurable increase in middle ear pressure during note generation and to provide evidence to clinicians to advise musicians undergoing middle ear surgery. An observational cohort study of 40 volunteers in 7 different wind instrument categories underwent tympanometry at rest and during note production. Community. Recreational musicians aged over 18 years recruited from the student body attending Birmingham University, UK. None. Tympanometry is used as a noninvasive measure of middle ear pressure. The pressure at which peak compliance occurred was taken as an indirect measure of middle ear pressure. The data produced at rest and during note production was statistically analysed with paired t testing and significance set at a p value less than 0.01. Overall a statistically significant increase in middle ear pressure change of 0.63 mm Hg (p = 0.0001) during note production was identified. Musicians playing the oboe and trumpet demonstrate the largest increase in middle ear pressure of 1.46 mm Hg (p = 0.0053) and 0.78 mm Hg (p = 0.0005) respectively. The data provided by this study gives evidence for the first time that playing wind instruments does increase middle ear pressure. Although the clinical significance of this is yet to be determined the authors would advise that musicians who undergo otological procedures should refrain from playing their instruments until full recovery has been achieved as advised by their clinician following direct microscopic review.

Ankrd6 is a mammalian functional homolog of Drosophila planar cell polarity gene diego and regulates coordinated cellular orientation in the mouse inner ear.

PubMed

Jones, Chonnettia; Qian, Dong; Kim, Sun Myoung; Li, Shuangding; Ren, Dongdong; Knapp, Lindsey; Sprinzak, David; Avraham, Karen B; Matsuzaki, Fumio; Chi, Fanglu; Chen, Ping

2014-11-01

The coordinated polarization of neighboring cells within the plane of the tissue, known as planar cell polarity (PCP), is a recurring theme in biology. It is required for numerous developmental processes for the form and function of many tissues and organs across species. The genetic pathway regulating PCP was first discovered in Drosophila, and an analogous but distinct pathway is emerging in vertebrates. It consists of membrane protein complexes known as core PCP proteins that are conserved across species. Here we report that the over-expression of the murine Ankrd6 (mAnkrd6) gene that shares homology with Drosophila core PCP gene diego causes a typical PCP phenotype in Drosophila, and mAnkrd6 can rescue the loss of function of diego in Drosophila. In mice, mAnkrd6 protein is asymmetrically localized in cells of the inner ear sensory organs, characteristic of components of conserved core PCP complexes. The loss of mAnkrd6 causes PCP defects in the inner ear sensory organs. Moreover, canonical Wnt signaling is significantly increased in mouse embryonic fibroblasts from mAnkrd6 knockout mice in comparison to wild type controls. Together, these results indicated that mAnkrd6 is a functional homolog of the Drosophila diego gene for mammalian PCP regulation and act to suppress canonical Wnt signaling. Copyright © 2014 Elsevier Inc. All rights reserved.

Plasticity within stem cell hierarchies in mammalian epithelia.

PubMed

Tetteh, Paul W; Farin, Henner F; Clevers, Hans

2015-02-01

Tissue homeostasis and regeneration are fueled by resident stem cells that have the capacity to self-renew, and to generate all the differentiated cell types that characterize a particular tissue. Classical models of such cellular hierarchies propose that commitment and differentiation occur unidirectionally, with the arrows 'pointing away' from the stem cell. Recent studies, all based on genetic lineage tracing, describe various strategies employed by epithelial stem cell hierarchies to replace damaged or lost cells. While transdifferentiation from one tissue type into another ('metaplasia') appears to be generally forbidden in nonpathological contexts, plasticity within an individual tissue stem cell hierarchy may be much more common than previously appreciated. In this review, we discuss recent examples of such plasticity in selected mammalian epithelia, highlighting the different modes of regeneration and their implications for our understanding of cellular hierarchy and tissue self-renewal. Copyright © 2014 Elsevier Ltd. All rights reserved.

Learning to perform ear reconstruction.

PubMed

Wilkes, Gordon H

2009-08-01

Learning how to perform ear reconstruction is very difficult. There are no standardized teaching methods. This has resulted in many ear reconstructions being suboptimal. Learning requires a major commitment by the surgeon. Factors to be seriously considered by those considering performing this surgery are (1) commitment, (2) aptitude, (3) training methods available, (4) surgical skills and experience, and (5) additional equipment needs. Unless all these factors are addressed in a surgeon's decision to perform this form of reconstruction, the end result will be compromised, and patient care will not be optimized. It is hoped that considering these factors and following this approach will result in a higher quality of aesthetic result. The future of ear reconstruction lies in the use of advanced digital technologies and tissue engineering. Copyright Thieme Medical Publishers.

Inner ear problems of Thai priest at Priest Hospital.

PubMed

Karnchanakas, Taweporn; Tantanavat, Are; Sinsakontavat, Jamjan

2008-01-01

The inner ear problems of Thai priest at Priest Hospital had never been reported previously, so Department of Ear Nose Throat try to correlate the metebotic disorder with inner ear problems. 1) To study the fasting blood sugar (FBS), total cholesterol (T. Chol), low density lipoprotein (LDL), and triglyceride (TG), the factors expected to involve in inner ear problems of priests at Priest Hospital. 2) To compare the FBS, T. Chol, HDL, LDL, and TG of priests with inner ear problems at Priest Hospital. 3) To find the percentage of abnormal from FBS, T. Chol, LDL, and TG. The study using 83 sampling of priests with inner ear problems and 107 priests as a controlled group. The research instruments used to collect data was the questionnaire which composed of general information, physical, ear-nose-throat and neurological examination, pure tone audiometry, brainstem evoke response audiometry (BERA) and the blood tests:FBS, T. Chol, TG, and LDL. The inner ear problems were composed of: 1) Dizziness 2) Hearing Loss 3) Tinnitus Aurium. The descriptive statistics were used to analyze the data from questionnaires and utilized frequency, percentage, standard deviation (S.D.) and t-test to achieve desired results. Priest at middle age and elderly with inner ear problems had greater FBS and TG than expected values of the control group. The middle age and elderly priests who had greater FBS and TG than expected values were sick with inner ear problems that causing dizziness, hearing loss and tinnitus aurium.

Evidence for a Right-Ear Advantage in Newborn Hearing Screening Results

PubMed Central

Hildesheimer, Minka; Roziner, Ilan; Henkin, Yael

2016-01-01

The aim of the present study was to investigate the effect of ear asymmetry, order of testing, and gender on transient-evoked otoacoustic emission (TEOAE) pass rates and response levels in newborn hearing screening. The screening results of 879 newborns, of whom 387 (study group) passed screening successfully in only one ear in the first TEOAE screening, but passed screening successfully in both ears thereafter, and 492 (control group) who passed screening successfully in both ears in the first TEOAE, were retrospectively examined for pass rates and TEOAE characteristics. Results indicated a right-ear advantage, as manifested by significantly higher pass rates in the right ear (61% and 39% for right and left ears, respectively) in the study group, and in 1.75 dB greater TEOAE response amplitudes in the control group. The right-ear advantage was enhanced when the first tested ear was the right ear (76%). When the left ear was tested first, pass rates were comparable in both ears. The right-ear advantage in pass rates was similar in females versus males, but manifested in 1.5 dB higher response amplitudes in females compared with males, regardless of the tested ear and order of testing in both study and control groups. The study provides further evidence for the functional lateralization of the auditory system at the cochlear level already apparent soon after birth in both males and females. While order of testing plays a significant role in the asymmetry in pass rates, the innate right-ear advantage seems to be a more dominant contributor. PMID:27927982

40 CFR 211.206-1 - Real ear method.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Real ear method. 211.206-1 Section 211... PRODUCT NOISE LABELING Hearing Protective Devices § 211.206-1 Real ear method. (a) The value of sound... “Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation of...

40 CFR 211.206-1 - Real ear method.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Real ear method. 211.206-1 Section 211... PRODUCT NOISE LABELING Hearing Protective Devices § 211.206-1 Real ear method. (a) The value of sound... “Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation of...

40 CFR 211.206-1 - Real ear method.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Real ear method. 211.206-1 Section 211... PRODUCT NOISE LABELING Hearing Protective Devices § 211.206-1 Real ear method. (a) The value of sound... “Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation of...

40 CFR 211.206-1 - Real ear method.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Real ear method. 211.206-1 Section 211... PRODUCT NOISE LABELING Hearing Protective Devices § 211.206-1 Real ear method. (a) The value of sound... “Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation of...

40 CFR 211.206-1 - Real ear method.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Real ear method. 211.206-1 Section 211... PRODUCT NOISE LABELING Hearing Protective Devices § 211.206-1 Real ear method. (a) The value of sound... “Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation of...

The fluid mechanics of the inner-ear disorder BPPV

NASA Astrophysics Data System (ADS)

Weidman, Michael; Squires, Todd; Stone, Howard

2001-11-01

The inner ear of mammals contains fluid-filled semi-circular canals with a flexible sensory membrane (called a cupula) which detects rotational acceleration. Benign Paroxysmal Positional Vertigo (BPPV) is one of the most common disorders of this system diagnosed today, and is characterized by symptoms of dizziness and nausea brought on by sudden changes in head orientation. BPPV is believed to have a mechanical (rather than nervous) origin, in which dense particles called otoconia settle into the canals and trigger false sensations of rotational acceleration. Several qualitative mechanisms have been proposed by the medical community, which we examine from a fluid mechanical standpoint. Traditionally, the semicircular canal and the cupula are modeled as an over-damped torsional pendulum with a driving force provided by rotational acceleration. We extend this model to include the time-dependent mechanical response owing to sedimentation of the otoconia. We make qualitative and quantitative predictions associated with the proposed mechanisms, with an eye towards differentiating between them and perhaps towards more effective diagnostic and therapeutic methods.

Ear-body lift and a novel thrust generating mechanism revealed by the complex wake of brown long-eared bats (Plecotus auritus)

NASA Astrophysics Data System (ADS)

Johansson, L. Christoffer; Håkansson, Jonas; Jakobsen, Lasse; Hedenström, Anders

2016-04-01

Large ears enhance perception of echolocation and prey generated sounds in bats. However, external ears likely impair aerodynamic performance of bats compared to birds. But large ears may generate lift on their own, mitigating the negative effects. We studied flying brown long-eared bats, using high resolution, time resolved particle image velocimetry, to determine the aerodynamics of flying with large ears. We show that the ears and body generate lift at medium to cruising speeds (3-5 m/s), but at the cost of an interaction with the wing root vortices, likely reducing inner wing performance. We also propose that the bats use a novel wing pitch mechanism at the end of the upstroke generating thrust at low speeds, which should provide effective pitch and yaw control. In addition, the wing tip vortices show a distinct spiraling pattern. The tip vortex of the previous wingbeat remains into the next wingbeat and rotates together with a newly formed tip vortex. Several smaller vortices, related to changes in circulation around the wing also spiral the tip vortex. Our results thus show a new level of complexity in bat wakes and suggest large eared bats are less aerodynamically limited than previous wake studies have suggested.

Principles of endoscopic ear surgery.

PubMed

Tarabichi, Muaaz; Kapadia, Mustafa

2016-10-01

The aim of this review is to study the rationale, limitations, techniques, and long-term outcomes of endoscopic ear surgery. The article discusses the advantages of endoscopic ear surgery in treating cholesteatoma and how the hidden sites like facial recess, sinus tympani, and anterior epitympanum are easily accessed using the endoscope. Transcanal endoscopic approach allows minimally invasive removal of cholesteatoma with results that compare well to traditional postauricular tympanomastoidectomy.

Middle Ear Infection (Chronic Otitis Media) and Hearing Loss

MedlinePlus

... You Middle Ear Infection (Chronic Otitis Media) and Hearing Loss Middle Ear Infection (Chronic Otitis Media) and ... loss. How does otitis media affect a child’s hearing? All children with middle ear infection or fluid ...

21 CFR 878.3590 - Ear prosthesis.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An...

21 CFR 878.3590 - Ear prosthesis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An...

21 CFR 878.3590 - Ear prosthesis.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An...

21 CFR 878.3590 - Ear prosthesis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An...

21 CFR 878.3590 - Ear prosthesis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An...

Three-Dimensional Analysis of the Ear Morphology.

PubMed

Modabber, Ali; Galster, Helmut; Peters, Florian; Möhlhenrich, Stephan Christian; Kniha, Kristian; Knobe, Matthias; Hölzle, Frank; Ghassemi, Alireza

2018-06-01

For surgical treatment of the face, detailed surgical planning is necessary to avoid later unaesthetic results. Most of the studies in the literature concentrate on the ears' anatomy during childhood and adolescence. Nearly no study evaluates the anatomy of ears of people aged 50 or older. It was our aim to measure and evaluate the ear's anatomy in Caucasians between the ages of 21 and 65. Three-dimensional scans of 240 volunteers were taken. The subjects were divided into groups of males and females and each of them into three groups by age (21-35, 36-50, 51-65). Landmarks were placed in these scans. Distances, relations and angles between them were recorded. The distance between the subaurale and superaurale significantly increases (p < 0.001) during the aging process in males and females. Also, the width of the ear, measured between the preaurale and postaurale, significantly increased (p = 0.007) with advancing age. When the length of the ear is divided into four parts by anatomical landmarks, it extended the most in the lower quadrant with increasing subject age. The ear of Caucasians does not stop changing its shape during adulthood. Even after the body has stopped growing, the ear still does. With the measured values in this study, it should be possible for the surgeon to plan the operation in advance and achieve satisfactory aesthetic outcomes. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Inverse solution of ear-canal area function from reflectance

PubMed Central

Rasetshwane, Daniel M.; Neely, Stephen T.

2011-01-01

A number of acoustical applications require the transformation of acoustical quantities, such as impedance and pressure that are measured at the entrance of the ear canal, to quantities at the eardrum. This transformation often requires knowledge of the shape of the ear canal. Previous attempts to measure ear-canal area functions were either invasive, non-reproducible, or could only measure the area function up to a point mid-way along the canal. A method to determine the area function of the ear canal from measurements of acoustic impedance at the entrance of the ear canal is described. The method is based on a solution to the inverse problem in which measurements of impedance are used to calculate reflectance, which is then used to determine the area function of the canal. The mean ear-canal area function determined using this method is similar to mean ear-canal area functions measured by other researchers using different techniques. The advantage of the proposed method over previous methods is that it is non- invasive, fast, and reproducible. PMID:22225043

Evidence for a Right-Ear Advantage in Newborn Hearing Screening Results.

PubMed

Ari-Even Roth, Daphne; Hildesheimer, Minka; Roziner, Ilan; Henkin, Yael

2016-12-06

The aim of the present study was to investigate the effect of ear asymmetry, order of testing, and gender on transient-evoked otoacoustic emission (TEOAE) pass rates and response levels in newborn hearing screening. The screening results of 879 newborns, of whom 387 (study group) passed screening successfully in only one ear in the first TEOAE screening, but passed screening successfully in both ears thereafter, and 492 (control group) who passed screening successfully in both ears in the first TEOAE, were retrospectively examined for pass rates and TEOAE characteristics. Results indicated a right-ear advantage, as manifested by significantly higher pass rates in the right ear (61% and 39% for right and left ears, respectively) in the study group, and in 1.75 dB greater TEOAE response amplitudes in the control group. The right-ear advantage was enhanced when the first tested ear was the right ear (76%). When the left ear was tested first, pass rates were comparable in both ears. The right-ear advantage in pass rates was similar in females versus males, but manifested in 1.5 dB higher response amplitudes in females compared with males, regardless of the tested ear and order of testing in both study and control groups. The study provides further evidence for the functional lateralization of the auditory system at the cochlear level already apparent soon after birth in both males and females. While order of testing plays a significant role in the asymmetry in pass rates, the innate right-ear advantage seems to be a more dominant contributor. © The Author(s) 2016.

Adeno-associated virus-mediated gene delivery into the scala media of the normal and deafened adult mouse ear.

PubMed

Kilpatrick, L A; Li, Q; Yang, J; Goddard, J C; Fekete, D M; Lang, H

2011-06-01

Murine models are ideal for studying cochlear gene transfer, as many hearing loss-related mutations have been discovered and mapped within the mouse genome. However, because of the small size and delicate nature, the membranous labyrinth of the mouse is a challenging target for the delivery of viral vectors. To minimize injection trauma, we developed a procedure for the controlled release of adeno-associated viruses (AAVs) into the scala media of adult mice. This procedure poses minimal risk of injury to structures of the cochlea and middle ear, and allows for near-complete preservation of low and middle frequency hearing. In this study, transduction efficiency and cellular specificity of AAV vectors (serotypes 1, 2, 5, 6 and 8) were investigated in normal and drug-deafened ears. Using the cytomegalovirus promoter to drive gene expression, a variety of cell types were transduced successfully, including sensory hair cells and supporting cells, as well as cells in the auditory nerve and spiral ligament. Among all five serotypes, inner hair cells were the most effectively transduced cochlear cell type. All five serotypes of AAV vectors transduced cells of the auditory nerve, though serotype 8 was the most efficient vector for transduction. Our findings indicate that efficient AAV inoculation (via the scala media) can be performed in adult mouse ears, with hearing preservation a realistic goal. The procedure we describe may also have applications for intra-endolymphatic drug delivery in many mouse models of human deafness.

Adeno-associated virus-mediated gene delivery into the scala media of the normal and deafened adult mouse ear

PubMed Central

Kilpatrick, Lauren A.; Li, Qian; Yang, John; Goddard, John C; Fekete, Donna M.; Lang, Hainan

2010-01-01

Murine models are ideal for studying cochlear gene transfer as many hearing loss-related mutations have been discovered and mapped within the mouse genome. However, due to its small size and delicate nature, the membranous labyrinth of the mouse is a challenging target for delivery of viral vectors. To minimize injection trauma, we developed a procedure for the controlled release of adeno-associated viruses (AAV) into the scala media of adult mice. This procedure poses minimal risk of injury to structures of the cochlea and middle ear and allows for near-complete preservation of low and middle frequency hearing. In the present study, transduction efficiency and cellular specificity of AAV vectors (serotypes 1, 2, 5, 6, and 8) were investigated in normal and drug-deafened ears. Using the cytomegalovirus (CMV) promoter to drive gene expression, a variety of cell types were transduced successfully, including sensory hair cells and supporting cells, as well as cells in the auditory nerve and spiral ligament. Among all five serotypes, inner hair cells (IHCs) were the most effectively transduced cochlear cell type. All five serotypes of AAV vectors transduced cells of the auditory nerve, though serotype 8 was the most efficient vector for transduction. Our findings indicate that efficient AAV inoculation (via the scala media) can be performed in adult mouse ears, with hearing preservation a realistic goal. The procedure we describe may also have applications for intra-endolymphatic drug delivery in many mouse models of human deafness. PMID:21209625

Physiological functioning of the ear and masking

NASA Technical Reports Server (NTRS)

1984-01-01

The physiological functions of the ear and the role masking plays in speech communication are examined. Topics under investigation include sound analysis of the ear, the aural reflex, and various types of noise masking.

Diode Laser Ear Piercing: A Novel Technique.

PubMed

Suseela, Bibilash Babu; Babu, Preethitha; Chittoria, Ravi Kumar; Mohapatra, Devi Prasad

2016-01-01

Earlobe piercing is a common office room procedure done by a plastic surgeon. Various methods of ear piercing have been described. In this article, we describe a novel method of laser ear piercing using the diode laser. An 18-year-old female patient underwent an ear piercing using a diode laser with a power of 2.0 W in continuous mode after topical local anaesthetic and pre-cooling. The diode laser was fast, safe, easy to use and highly effective way of ear piercing. The advantages we noticed while using the diode laser over conventional methods were more precision, minimal trauma with less chances of hypertrophy and keloids, no bleeding with coagulation effect of laser, less time taken compared to conventional method and less chance of infection due to thermal heat effect of laser.

APICAL LOCATION OF FERROPORTIN 1 IN AIRWAY EPITHELIA AND ITS ROLE IN IRON DETOXIFICATION IN THE LUNG

EPA Science Inventory

Ferroportin 1 (FPN1; aka MTP1, IREG1, and SLC40A1), which was originally identified as a basolateral iron transporter crucial for nutritional iron absorption in the intestine, is expressed in airway epithelia and upregulated when these cells are exposed to iron. Using immunofluor...

Sensory impairment and driving: the Blue Mountains Eye Study.

PubMed Central

Ivers, R Q; Mitchell, P; Cumming, R G

1999-01-01

OBJECTIVES: This study examined the associations between vision, hearing, loss, and car accidents. METHODS: A cross-sectional survey of 3654 people aged 49 years and older in the Blue Mountains, Australia, was used. Each subject had a detailed eye examination and interview. RESULTS: Self-reported car accident rates in the past year among 2379 current drivers were 5.6% for those aged 49 to 79 years and 9.1% for those 80 years and older. A 2-line difference in visual acuity was associated with increased risk of accidents (adjusted prevalence ratio [PR] = 1.6), as was visual acuity worse than 6/18 in the right eye (PR = 2.0), overall moderate hearing loss (PR = 1.9), and hearing loss in the right ear (PR = 1.8). CONCLUSIONS: Sensory loss in drivers may be an important risk factor for car accidents. PMID:9987472

Magnetically driven middle ear ossicles for optical measurement of vibrations in an ear with opened tympanic membrane

NASA Astrophysics Data System (ADS)

Peacock, J.; von Unge, M.; Dirckx, J.

2013-12-01

Vibrations of the middle ear ossicles are easily measured by means of laser vibrometry. However, laser vibrometry requires free visual access to the object under investigation, and acquiring free visual access to the ossicles through the ear canal requires the removal of the tympanic membrane (TM), with the result that the ossicles can no longer be stimulated acoustically. To overcome this, we devised a new setup in which the ossicles can be driven magnetically. After measuring the response of the TM to an acoustic signal, we then remove it and attach a small magnet to the exposed manubrium (a part of the most lateral auditory ossicle, the malleus, which is normally attached to the TM). An electromagnetic excitation coil is then used to drive the magnet, and the output to the coil adjusted until the vibration of the manubrium, as measured by the vibrometer, matches that measured in response to the acoustic signal. Such a setup may have uses in research on middle ear mechanics, such as the measurement of nonlinearities in their response, as well as applications in the diagnosis of middle ear conditions such as the fixation of the ossicles by otosclerosis or in chronic otitis media. We describe our setup and discuss the viability of our method and its future clinical potential by presenting some measurements on an artificially fixated ear.

Targeted deletion of Atg5 reveals differential roles of autophagy in keratin K5-expressing epithelia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sukseree, Supawadee; Department of Biochemistry, Faculty of Medicine, Srinakharinwirot University, Bangkok; Rossiter, Heidemarie

2013-01-11

Highlights: Black-Right-Pointing-Pointer We generated mice lacking Atg5 and autophagy in keratin K5-positive epithelia. Black-Right-Pointing-Pointer Suppression of autophagy in thymic epithelium was not associated with signs of autoimmunity. Black-Right-Pointing-Pointer Autophagy was required for normal terminal differentiation of preputial gland cells. Black-Right-Pointing-Pointer Autophagy-deficient cells of the preputial glands degraded nuclear DNA prematurely. -- Abstract: Autophagy contributes to the homeostasis of many tissues, yet its role in epithelia is incompletely understood. A recent report proposed that Atg5-dependent autophagy in thymic epithelial cells is essential for their function in the negative selection of self-reactive T-cells and, thus, for the suppression of tissue inflammation. Heremore » we crossed mice carrying floxed alleles of the Atg5 gene with mice expressing the Cre recombinase under the control of the keratin K5 promoter to suppress autophagy in all K5-positive epithelia. The efficiency of autophagy abrogation was confirmed by immunoanalyses of LC3, which was converted to the autophagy-associated LC3-II form in normal but not Atg5-deficient cells, and of p62, which accumulated in Atg5-deficient cells. Mice carrying the epithelium-specific deletion of Atg5 showed normal weight gain, absence of tissue inflammation, and a normal morphology of the thymic epithelium. By contrast, autophagy-deficient epithelial cells of the preputial gland showed aberrant eosinophilic staining in histology and premature degradation of nuclear DNA during terminal differentiation. Taken together, the results of this study suggest that autophagy is dispensable for the suppression of autoimmunity by thymic epithelial cells but essential for normal differentiation of the preputial gland in mice.« less

Cauliflower Ear and Skin Infections among Wrestlers in Tehran

PubMed Central

Kordi, Ramin; Mansournai, Mohammad Ali; Nourian, Roh Allah; Wallace, W. Angus

2007-01-01

The purpose of the study was to describe the magnitude of the selected sports medicine problems (i.e. cauliflower ear and skin infections) among wrestlers in Tehran. A number of 411 wrestlers were randomly selected from wrestling clubs in Tehran employing cluster sample setting method. The participants were interviewed using a specially designed and validated questionnaire. Nearly half of the participants (44%) had “cauliflower ears”. Only 23% of these participants had received any kind of treatment for their acute ear haematomas that are known to result in “cauliflower ears”. The prevalence of reported hearing loss among participants with cauliflower ears (11.5%, 95%CI: 6.9 to 16.2) was significantly more than this prevalence among those participants without cauliflower ears (1.8%, 95%CI: 0.1 to 3.5) (p < 0.05). More than half of the participants (52%) had skin infection diagnosed by a physician during the previous year. This study has identified evidence of an increase in hearing loss as a possible side effect of either cauliflower ear or ear injury in wrestling in Iran. There has been an outbreak of ringworm and there is a significant potential for an outbreak of impetigo among wrestlers in Tehran. Key points Skin infections are prevalent among wrestlers in Tehran. Commonly wrestlers in Tehran continue to carry out wrestling training while affected by skin infections. Cauliflower ear ”is common among wrestlers in Tehran. More research is needed to investigate hearing loss as a possible side effect of either cauliflower ear or ear injury in wrestling in Iran. PMID:24198702

Can you hear me now? Understanding vertebrate middle ear development

PubMed Central

Chapman, Susan Caroline

2010-01-01

The middle ear is a composite organ formed from all three germ layers and the neural crest. It provides the link between the outside world and the inner ear, where sound is transduced and routed to the brain for processing. Extensive classical and modern studies have described the complex morphology and origin of the middle ear. Non-mammalian vertebrates have a single ossicle, the columella. Mammals have three functionally equivalent ossicles, designated the malleus, incus and stapes. In this review, I focus on the role of genes known to function in the middle ear. Genetic studies are beginning to unravel the induction and patterning of the multiple middle ear elements including the tympanum, skeletal elements, the air-filled cavity, and the insertion point into the inner ear oval window. Future studies that elucidate the integrated spatio-temporal signaling mechanisms required to pattern the middle ear organ system are needed. The longer-term translational benefits of understanding normal and abnormal ear development will have a direct impact on human health outcomes. PMID:21196256

Precise individualized armature for ear reconstruction

NASA Astrophysics Data System (ADS)

Evenhouse, Raymond J.; Chen, Xiaoming

1991-04-01

The cosmetic result of an ear restored surgically or via prosthetics is dependent on the surgeon''s ability to carve a precise cartilage armature at the time of surgery or the prosthetist''s ability to sculpt in wax an exact duplicate of the patient''s " missing" ear. Introducing CAD/CAM technology into the process benefits the esthetic outcome of these procedures. By utilizing serial section information derived from CAT MRI or moulage techniques a mirrorimage of the patient''s " donor" ear is generated. The resulting earform data is then used for the design of a cartilage armature produced by multi-axis milling or to produce by stereolithography a model which serves as the basis for a prosthesis.

Building an endoscopic ear surgery program.

PubMed

Golub, Justin S

2016-10-01

This article discusses background, operative details, and outcomes of endoscopic ear surgery. This information will be helpful for those establishing a new program. Endoscopic ear surgery is growing in popularity. The ideal benefit is in totally transcanal access that would otherwise require a larger incision. The endoscope carries a number of advantages over the microscope, as well as some disadvantages. Several key maneuvers can minimize disadvantages. There is a paucity of studies directly comparing outcomes between endoscopic and microscopic approaches for the same procedure. The endoscope is gaining acceptance as a tool for treating otologic diseases. For interested surgeons, this article can help bridge the transition from microscopic to totally transcanal endoscopic ear surgery for appropriate disease.

The small intestinal epithelia of beef steers differentially express sugar transporter messenger ribonucleic acid in response to abomasal versus ruminal infusion of starch hydrolysate.

PubMed

Liao, S F; Harmon, D L; Vanzant, E S; McLeod, K R; Boling, J A; Matthews, J C

2010-01-01

In mammals, the absorption of monosaccharides from small intestinal lumen involves at least 3 sugar transporters (SugT): sodium-dependent glucose transporter 1 (SGLT1; gene SLC5A1) transports glucose and galactose, whereas glucose transporter (GLUT) 5 (GLUT5; gene SLC2A5) transports fructose, across the apical membrane of enterocytes. In contrast, GLUT2 (gene SLC2A2) transports all of these sugars across basolateral and apical membranes. To compare the distribution patterns and sensitivity with nutritional regulation of these 3 SugT mRNA in beef cattle small intestinal tissue, 18 ruminally and abomasally catheterized Angus steers (BW approximately 260 kg) were assigned to water (control), ruminal cornstarch (partially hydrolyzed by alpha-amylase; SH), or abomasal SH infusion treatments (n = 6) and fed an alfalfa-cube-based diet at 1.3 x NE(m) requirement. The SH infusions amounted to 20% of ME intake. After 14- or 16-d of infusion, steers were killed; duodenal, jejunal, and ileal epithelia harvested; and total RNA extracted. The relative amount of SugT mRNA in epithelia was determined using real-time reverse transcription-PCR quantification methods. Basal expression of GLUT2 and SGLT1 mRNA was greater (P < 0.09) by jejunal than by duodenal or ileal epithelia, whereas basal content of GLUT5 mRNA was greater (P < or = 0.02) by jejunal and duodenal than by ileal epithelia. The content of GLUT5 mRNA in small intestinal epithelia was not affected (P > or = 0.16) by either SH infusion treatment. In contrast, GLUT2 and SGLT1 mRNA content in the ileal epithelium was increased (P < or = 0.05) by 6.5- and 1.3-fold, respectively, after abomasal SH infusion. Duodenal SGLT1 mRNA content also was increased (P = 0.07) by 64% after ruminal SH infusion. These results demonstrate that the ileum of beef cattle small intestine adapts to an increased luminal supply of glucose by increasing SGLT1 and GLUT2 mRNA content, whereas increased ruminal SH supply results in duodenal

Playing by Ear: Foundation or Frill?

ERIC Educational Resources Information Center

Woody, Robert H.

2012-01-01

Many people divide musicians into two types: those who can read music and those who play by ear. Formal music education tends to place great emphasis on producing musically literate performers but devotes much less attention to teaching students to make music without notation. Some would suggest that playing by ear is a specialized skill that is…

Continuous long-term measurements of the middle ear pressure in subjects without a history of ear disease.

PubMed

Tideholm, B; Carlborg, B; Jönsson, S; Bylander-Groth, A

1998-06-01

A new method was used for continuous measurement of the middle ear (ME) pressure during a 24-h period. In 10 subjects without a history of ear disease a small perforation was made through the tympanic membrane. A tight rubber stopper containing a small polyethylene tube was fitted into the external ear canal. Conventional tubal function tests were performed. The equipment was then carried by the subjects for 24 h of normal activity to monitor any slow or rapid dynamic pressure change in the ME. Body position was found to be the most important factor affecting ME pressure variation, during the 24-h continuous pressure measurements. A significant pressure rise occurred in the recumbent position in all but one subject. Few rapid pressure equilibrations were seen during the recordings, indicating few tubal openings. This implies that the pressure changes in the ME seen in this study were mainly the result of gas exchange over the mucosa. The investigation might be a base for reference when investigating different kinds of pathologic conditions in the ear.

Anisotropic yield function capable of predicting eight ears

NASA Astrophysics Data System (ADS)

Yoon, J. H.; Cazacu, O.

2011-08-01

Deep drawing of a cylindrical cup from a rolled sheet is one of the typical forming operations where the effect of this anisotropy is most evident. Indeed, it is well documented in the literature that the number of ears and the shape of the earing pattern correlate with the r-values profile. For the strongly textured aluminum alloy AA 5042 (Numisheet Benchmark 2011), the experimental r-value distribution has two minima between the rolling and transverse direction data provided for this show that the r-value along the transverse direction (TD) is five times larger than the value corresponding to the rolling direction. Therefore, it is expected that there are more that the earing profile has more than four ears. The main objective of this paper is to assess whether a new form of CPB06ex2 yield function (Plunkett et al. (2008)) tailored for metals with no tension-compression asymmetry is capable of predicting more than four ears for this material.

Inner ear abnormalities in patients with Goldenhar syndrome.

PubMed

Bisdas, Sotirios; Lenarz, Minoo; Lenarz, Thomas; Becker, Hartmut

2005-05-01

The objective of this study is to investigate the inner ear malformations in patients with Goldenhar syndrome and to hypothesize the potential embryopathogenesis of these malformations. Retrospective case review. Tertiary referral center. Fourteen patients with Goldenhar syndrome. Each patient underwent hearing tests and high-resolution computed tomography (CT) of the temporal bone. In six patients, magnetic resonance imaging of the temporal bone also was performed. Among the 14 patients with Goldenhar syndrome, 13 had outer and middle ear anomalies and 5 (36%) had inner ear malformations, including one case of common cavity. Our observations regarding inner ear anomalies in Goldenhar syndrome correlate with the reported cases in the literature and may help to hypothesize the embryological origin of these malformations, which can caused by an early developmental arrest in the fourth gestational week. Specialists evaluating patients with Goldenhar syndrome should be aware of the possibility of inner ear malformations, which could be diagnosed earlier with appropriate imaging studies.

A novel buoyancy technique optimizes simulated microgravity conditions for whole sensory organ culture in rotating bioreactors.

PubMed

Arnold, Heinz J P; Müller, Marcus; Waldhaus, Jörg; Hahn, Hartmut; Löwenheim, Hubert

2010-02-01

Whole-organ culture of a sensory organ in a rotating wall vessel bioreactor provides a powerful in vitro model for physiological and pathophysiological investigation as previously demonstrated for the postnatal inner ear. The model is of specific relevance as a tool for regeneration research. In the immature inner ear explant, the density was only 1.29 g/cm(3). The high density of 1.68 g/cm(3) of the functionally mature organ resulted in enhanced settling velocity and deviation from its ideal circular orbital path causing enhanced shear stress. The morphometric and physical properties, as well as the dynamic motion patterns of explants, were analyzed and numerically evaluated by an orbital path index. Application of a novel buoyancy bead technique resulted in a 6.5- to 14.8-fold reduction of the settling velocity. The deviation of the explant from its ideal circular orbital path was adjusted as indicated by an optimum value for the orbital path index (-1.0). Shear stress exerted on the inner ear explant was consequently reduced 6.4- to 15.0-fold. The culture conditions for postnatal stages were optimized, and the preconditions for transferring this in vitro model toward mature high-density stages established. This buoyancy technique may also be useful in tissue engineering of other high-density structures.

Cosmetic ear surgery

MedlinePlus

... ear reduction. In: Rubin JP, Neligan PC, eds. Plastic Surgery: Volume 2: Aesthetic Surgery . 4th ed. Philadelphia, ... Tang Ho, MD, Assistant Professor, Division of Facial Plastic and Reconstructive Surgery, Department of Otolaryngology – Head and ...

Ear infection - acute

MedlinePlus

... more than 6 children) Changes in altitude or climate Cold climate Exposure to smoke Family history of ear infections ... Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Internal review and update ...

Sensory Acceptability of Iron-Fortified Red Lentil (Lens culinaris Medik.) Dal.

PubMed

Podder, Rajib; Khan, Shaan M; Tar'an, Bunyamin; Tyler, Robert T; Henry, Carol J; Jalal, Chowdhury; Shand, Phyllis J; Vandenberg, Albert

2018-03-01

Panelists in Saskatoon, Canada (n = 45) and Dhaka, Bangladesh (n = 98) participated in sensory evaluations of the sensory properties of both cooked and uncooked dehulled red lentil dal fortified with FeSO 4 ·7H 2 O, NaFeEDTA or FeSO 4 ·H 2 O at fortificant Fe concentrations of 800, 1,600 (both cooked and uncooked), or 2,800 ppm. Appearance, odor, and overall acceptability of cooked and uncooked samples were rated using a 9-point hedonic scale (1 = dislike extremely to 9 = like extremely). Taste and texture were rated for the cooked samples prepared as typical south Asian lentil meals. Significant differences in sensory quality were observed among all uncooked and cooked samples at both locations. Overall, scores for all sensory attributes and acceptability of uncooked lentil decreased with increasing concentration of Fe in the fortificant; however, Fe fortification (particularly with NaFeEDTA) had small effects on acceptability. Panelists from Saskatoon provided a wider range of scores than those from Bangladesh for all attributes of cooked lentil. Overall, sensory evaluation of Fe fortification using NaFeEDTA minimally affected consumer perception of color, taste, texture, odor, and overall acceptability of cooked lentil. Reliability estimates (Cronbach's alpha [CA]) indicated that consumer scores were generally consistent for all attributes of all lentil samples (mean CA > 0.80). NaFeEDTA was found to be the most suitable Fe fortificant for lentil based on consumer acceptability. Consumption of 45 to 50 g of NaFeEDTA-fortified lentil (fortificant Fe concentration of 1,600 ppm) per day meets the estimated average requirements (EARs) of Fe for humans (10.8 to 29.4 mg). Iron fortification of dehulled lentil dal may change organoleptic attributes that can influence consumer acceptability. Sensory evaluation by consumers helps to determine the effect on appearance, odor, taste, texture, and overall acceptability of fortified lentils. In this study, consumer

The physics of hearing: fluid mechanics and the active process of the inner ear.

PubMed

Reichenbach, Tobias; Hudspeth, A J

2014-07-01

Most sounds of interest consist of complex, time-dependent admixtures of tones of diverse frequencies and variable amplitudes. To detect and process these signals, the ear employs a highly nonlinear, adaptive, real-time spectral analyzer: the cochlea. Sound excites vibration of the eardrum and the three miniscule bones of the middle ear, the last of which acts as a piston to initiate oscillatory pressure changes within the liquid-filled chambers of the cochlea. The basilar membrane, an elastic band spiraling along the cochlea between two of these chambers, responds to these pressures by conducting a largely independent traveling wave for each frequency component of the input. Because the basilar membrane is graded in mass and stiffness along its length, however, each traveling wave grows in magnitude and decreases in wavelength until it peaks at a specific, frequency-dependent position: low frequencies propagate to the cochlear apex, whereas high frequencies culminate at the base. The oscillations of the basilar membrane deflect hair bundles, the mechanically sensitive organelles of the ear's sensory receptors, the hair cells. As mechanically sensitive ion channels open and close, each hair cell responds with an electrical signal that is chemically transmitted to an afferent nerve fiber and thence into the brain. In addition to transducing mechanical inputs, hair cells amplify them by two means. Channel gating endows a hair bundle with negative stiffness, an instability that interacts with the motor protein myosin-1c to produce a mechanical amplifier and oscillator. Acting through the piezoelectric membrane protein prestin, electrical responses also cause outer hair cells to elongate and shorten, thus pumping energy into the basilar membrane's movements. The two forms of motility constitute an active process that amplifies mechanical inputs, sharpens frequency discrimination, and confers a compressive nonlinearity on responsiveness. These features arise because the

The physics of hearing: fluid mechanics and the active process of the inner ear

NASA Astrophysics Data System (ADS)

Reichenbach, Tobias; Hudspeth, A. J.

2014-07-01

Most sounds of interest consist of complex, time-dependent admixtures of tones of diverse frequencies and variable amplitudes. To detect and process these signals, the ear employs a highly nonlinear, adaptive, real-time spectral analyzer: the cochlea. Sound excites vibration of the eardrum and the three miniscule bones of the middle ear, the last of which acts as a piston to initiate oscillatory pressure changes within the liquid-filled chambers of the cochlea. The basilar membrane, an elastic band spiraling along the cochlea between two of these chambers, responds to these pressures by conducting a largely independent traveling wave for each frequency component of the input. Because the basilar membrane is graded in mass and stiffness along its length, however, each traveling wave grows in magnitude and decreases in wavelength until it peaks at a specific, frequency-dependent position: low frequencies propagate to the cochlear apex, whereas high frequencies culminate at the base. The oscillations of the basilar membrane deflect hair bundles, the mechanically sensitive organelles of the ear's sensory receptors, the hair cells. As mechanically sensitive ion channels open and close, each hair cell responds with an electrical signal that is chemically transmitted to an afferent nerve fiber and thence into the brain. In addition to transducing mechanical inputs, hair cells amplify them by two means. Channel gating endows a hair bundle with negative stiffness, an instability that interacts with the motor protein myosin-1c to produce a mechanical amplifier and oscillator. Acting through the piezoelectric membrane protein prestin, electrical responses also cause outer hair cells to elongate and shorten, thus pumping energy into the basilar membrane's movements. The two forms of motility constitute an active process that amplifies mechanical inputs, sharpens frequency discrimination, and confers a compressive nonlinearity on responsiveness. These features arise because the

AGE-RELATED FUNCTIONAL AND HISTOPATHOLOGICAL CHANGES OF THE EAR IN THE MPS I MOUSE

PubMed Central

Schachern, Patricia A.; Cureoglu, Sebahattin; Tsuprun, Vladimir; Paparella, Michael M.; Whitley, Chester

2007-01-01

Objective Mucopolysaccharidosis type I (MPS I) is an autosomal recessive disorder caused by a mutation in the gene encoding the enzyme α-L-iduronidase. This enzyme is responsible for degradation of dermatan and heparan sulfates. Enzyme deficiency results in their accumulation in lysosomes of virtually all organs, resulting in severe somatic and neurological changes. Clinical findings of otitis media with mixed hearing loss are common. Cellular and molecular mechanisms of ear pathology and hearing loss are not understood. The purpose of this study is to describe the age-related audiologic and histopathologic changes of the ear in the mouse model of MPS I. Methods Auditory brainstemresponses (ABR) were obtained to clicks and tone bursts at 1-32 kHz, and pathological changes to middle and inner ears were studied with light and electron microscopy in fifty-three mice that included: 1) wild type (+/+) - five at 2 months, five at 4 to 6 months, and five at 13 to 19 months; 2) heterozygotes (+/−) - four at 2 months; five at 4 to 6 months; and eight at 13 to 19 months; and 3) homozygotes (−/−); five at 2 months; six at 4 to 6 months; and five at 13 to 19 months. Histopathology was also done on five newborn −/− mice. Results In newborns no lysosomal storage was observed and the ear appeared age appropriately normal. In all other −/− mice, cells with lysosomal storage vacuoles were observed in spiral ligament, spiral prominence, spiral limbus, basilar membrane, epithelial and mesothelial cells of Reissner’s membrane, endothelial cells of vessels, and some ganglion cells; their number increased with aging. Hair cell loss was not observed at 2 or 6 months, but there was total loss of the organ of Corti in year-old mice. Hearing of −/− mice was significantly decreased at all ages compared to +/+ and +/−. Hearing loss progressed from mild to moderate loss at 2 months to profound at 6 months and total deafness by one year of age. Conclusions Progressive age

Continuous 24-hour measurement of middle ear pressure.

PubMed

Tideholm, B; Jönsson, S; Carlborg, B; Welinder, R; Grenner, J

1996-07-01

A new method was developed for continuous measurement of the middle ear pressure during a 24-h period. The equipment consisted of a piezo-electric pressure device and a digital memory. To allow continuous pressure recordings during normal every-day activities the equipment was made light and portable. The measurement accuracy of the equipment as well as the base-line and temperature stability were tested and found to meet to our requirements satisfactorily. In 4 volunteers with different middle ear conditions, a small perforation was made through the tympanic membrane. A rubber stopper containing a small polyethylene tube was fitted into the external ear canal. Tubal function tests were made to establish the equipment's ability to monitor fast pressure changes. The tests were well in accordance with other methods of direct pressure measurements. The equipment was carried by the volunteers for 24 h to monitor any slow or rapid dynamic pressure changes in the middle ear. Four continuous 24-h measurements are presented. The method was found to be suitable for valid measurements of dynamic pressure changes in the middle ear during normal every-day activities. It may become a useful instrument in the search for a better understanding of the development of chronic middle ear disease.

Fgf8 and Fgf3 are required for zebrafish ear placode induction, maintenance and inner ear patterning.

PubMed

Léger, Sophie; Brand, Michael

2002-11-01

The vertebrate inner ear develops from initially 'simple' ectodermal placode and vesicle stages into the complex three-dimensional structure which is necessary for the senses of hearing and equilibrium. Although the main morphological events in vertebrate inner ear development are known, the genetic mechanisms controlling them are scarcely understood. Previous studies have suggested that the otic placode is induced by signals from the chordamesoderm and the hindbrain, notably by fibroblast growth factors (Fgfs) and Wnt proteins. Here we study the role of Fgf8 as a bona-fide hindbrain-derived signal that acts in conjunction with Fgf3 during placode induction, maintenance and otic vesicle patterning. Acerebellar (ace) is a mutant in the fgf8 gene that results in a non-functional Fgf8 product. Homozygous mutants for acerebellar (ace) have smaller ears that typically have only one otolith, abnormal semi-circular canals, and behavioral defects. Using gene expression markers for the otic placode, we find that ace/fgf8 and Fgf-signaling are required for normal otic placode formation and maintenance. Conversely, misexpression of fgf8 or Fgf8-coated beads implanted into the vicinity of the otic placode can increase ear size and marker gene expression, although competence to respond to the induction appears restricted. Cell transplantation experiments and expression analysis suggest that Fgf8 is required in the hindbrain in the rhombomere 4-6 area to restore normal placode development in ace mutants, in close neighbourhood to the forming placode, but not in mesodermal tissues. Fgf3 and Fgf8 are expressed in hindbrain rhombomere 4 during the stages that are critical for placode induction. Joint inactivation of Fgf3 and Fgf8 by mutation or antisense-morpholino injection causes failure of placode formation and results in ear-less embryos, mimicking the phenotype we observe after pharmacological inhibition of Fgf-signaling. Fgf8 and Fgf3 together therefore act during induction

Morphological Variations and Biometrics of Ear: An Aid to Personal Identification.

PubMed

Verma, Pradhuman; Sandhu, Harpreet Kaur; Verma, Kanika Gupta; Goyal, Sharry; Sudan, Madhu; Ladgotra, Amit

2016-05-01

The morphological characteristics and dimensions of external ear vary in different human ethnic races which can be utilized in forensics for personal identification of living or deceased. To determine uniqueness of morphological and biometric variations of both ears for individualization among North East (NE) and North West (NW) subpopulation of India. The study was conducted on randomly selected 80 students, 40 from each subgroup. Nine ear parameters were recorded twice using digital Vernier's caliper by single investigator and two indices (Ear Index and Lobule Index) were calculated for both the ears. Morphological ear shapes and lobule attachment were also noted. Pearson's coefficient correlation test was performed on cross-tabulations to evaluate significant relationship between different variables. Of the total 35% free and 65% attached ear lobes were noted in both population groups. Oval ear shape was most commonly noted followed by triangular, rectangular and round in both populations. On comparing anthropometric measurements of ears in two populations it was found that except the tragus length and lobule index all other values were noted more in NW population. No statistical difference was found in ear and lobular indices of males and females although the left ear index and lobule index were found to be higher than right in both populations except in NW females where right lobule index was recorded more than left. The results obtained can be used in anthropological and forensic sciences for the inclusion and exclusion of persons for identification on the basis of ear variations.

Békésy's contributions to our present understanding of sound conduction to the inner ear.

PubMed

Puria, Sunil; Rosowski, John J

2012-11-01

In our daily lives we hear airborne sounds that travel primarily through the external and middle ear to the cochlear sensory epithelium. We also hear sounds that travel to the cochlea via a second sound-conduction route, bone conduction. This second pathway is excited by vibrations of the head and body that result from substrate vibrations, direct application of vibrational stimuli to the head or body, or vibrations induced by airborne sound. The sensation of bone-conducted sound is affected by the presence of the external and middle ear, but is not completely dependent upon their function. Measurements of the differential sensitivity of patients to airborne sound and direct vibration of the head are part of the routine battery of clinical tests used to separate conductive and sensorineural hearing losses. Georg von Békésy designed a careful set of experiments and pioneered many measurement techniques on human cadaver temporal bones, in physical models, and in human subjects to elucidate the basic mechanisms of air- and bone-conducted sound. Looking back one marvels at the sheer number of experiments he performed on sound conduction, mostly by himself without the aid of students or research associates. Békésy's work had a profound impact on the field of middle-ear mechanics and bone conduction fifty years ago when he received his Nobel Prize. Today many of Békésy's ideas continue to be investigated and extended, some have been supported by new evidence, some have been refuted, while others remain to be tested. Copyright © 2012 Elsevier B.V. All rights reserved.

Comparison of Middle Ear Visualization With Endoscopy and Microscopy.

PubMed

Bennett, Marc L; Zhang, Dongqing; Labadie, Robert F; Noble, Jack H

2016-04-01

The primary goal of chronic ear surgery is the creation of a safe, clean dry ear. For cholesteatomas, complete removal of disease is dependent on visualization. Conventional microscopy is adequate for most dissection, but various subregions of the middle ear are better visualized with endoscopy. The purpose of the present study was to quantitatively assess the improved visualization that endoscopes afford as compared with operating microscopes. Microscopic and endoscopic views were simulated using a three-dimensional model developed from temporal bone scans. Surface renderings of the ear canal and middle ear subsegments were defined and the percentage of visualization of each middle ear subsegment, both with and without ossicles, was then determined for the microscope as well as for 0-, 30-, and 45-degree endoscopes. Using this information, we analyzed which mode of visualization is best suited for dissection within a particular anatomical region. Using a 0-degree scope provides significantly more visualization of every subregion, except the antrum, compared with a microscope. In addition, angled scopes permit visualizing significantly more surface area of every subregion of the middle ear than straight scopes or microscopes. Endoscopes offer advantages for cholesteatoma dissection in difficult-to-visualize areas including the sinus tympani and epitympanum.

CD44s and CD44v6 Expression in Head and Neck Epithelia

PubMed Central

Mack, Brigitte; Gires, Olivier

2008-01-01

Background CD44 splice variants are long-known as being associated with cell transformation. Recently, the standard form of CD44 (CD44s) was shown to be part of the signature of cancer stem cells (CSCs) in colon, breast, and in head and neck squamous cell carcinomas (HNSCC). This is somewhat in contradiction to previous reports on the expression of CD44s in HNSCC. The aim of the present study was to clarify the actual pattern of CD44 expression in head and neck epithelia. Methods Expression of CD44s and CD44v6 was analysed by immunohistochemistry with specific antibodies in primary head and neck tissues. Scoring of all specimens followed a two-parameters system, which implemented percentages of positive cells and staining intensities from − to +++ (score = %×intensity; resulting max. score 300). In addition, cell surface expression of CD44s and CD44v6 was assessed in lymphocytes and HNSCC. Results In normal epithelia CD44s and CD44v6 were expressed in 60–95% and 50–80% of cells and yielded mean scores with a standard error of a mean (SEM) of 249.5±14.5 and 198±11.13, respectively. In oral leukoplakia and in moderately differentiated carcinomas CD44s and CD44v6 levels were slightly increased (278.9±7.16 and 242±11.7; 291.8±5.88 and 287.3±6.88). Carcinomas in situ displayed unchanged levels of both proteins whereas poorly differentiated carcinomas consistently expressed diminished CD44s and CD44v6 levels. Lymphocytes and HNSCC lines strongly expressed CD44s but not CD44v6. Conclusion CD44s and CD44v6 expression does not distinguish normal from benign or malignant epithelia of the head and neck. CD44s and CD44v6 were abundantly present in the great majority of cells in head and neck tissues, including carcinomas. Hence, the value of CD44s as a marker for the definition of a small subset of cells (i.e. less than 10%) representing head and neck cancer stem cells may need revision. PMID:18852874

INNER EAR EMBRYOGENESIS: GENETIC AND ENVIRONMENTAL DETERMINANTS

EPA Science Inventory

The anatomy and developmental molecular genetics of the inner ear from establishment of the otic placode to formation of the definitive cochlea and vestibular apparatus will be reviewed and the complex 3-D structural changes that shape the developing inner ear will be illustrated...

Effects of a sensory branch to the posterior external ear canal: coughing, pain, Ramsay Hunt's syndrome and Hitselberger's sign.

PubMed

Mulazimoglu, S; Flury, R; Kapila, S; Linder, T

2017-04-01

A distinct nerve innervating the external auditory canal can often be identified in close relation to the facial nerve when gradually thinning the posterior canal wall. This nerve has been attributed to coughing during cerumen removal, neuralgic pain, Hitselberger's sign and vesicular eruptions described in Ramsay Hunt's syndrome. This study aimed to demonstrate the origin and clinical impact of this nerve. In patients with intractable otalgia or severe coughing whilst inserting a hearing aid, who responded temporarily to local anaesthesia, the symptoms could be resolved by sectioning a sensory branch to the posterior canal. In a temporal bone specimen, it was revealed that this nerve is predominantly a continuation of Arnold's nerve, also receiving fibres from the glossopharyngeal nerve and facial nerve. Histologically, the communicating branch from the facial nerve was confirmed. Surgeons should be aware of the posterior auricular sensory branch and its clinical implications.

Ear-protector ratings.

DOT National Transportation Integrated Search

1973-12-01

Twenty-one brands of ear protectors, including custom-molded, wearer-molded, and pre-molded types, were evaluated according to American-standard procedures. Earplugs are described and are listed in the order of their low-frequency (below 1000 Hz) att...

Single-cell RNA-Seq reveals cell heterogeneity and hierarchy within mouse mammary epithelia.

PubMed

Sun, Heng; Miao, Zhengqiang; Zhang, Xin; Chan, Un In; Su, Sek Man; Guo, Sen; Wong, Chris Koon Ho; Xu, Xiaoling; Deng, Chu-Xia

2018-06-01

The mammary gland is very intricately and well organized into distinct tissues, including epithelia, endothelia, adipocytes, and stromal and immune cells. Many mammary gland diseases, such as breast cancer, arise from abnormalities in the mammary epithelium, which is mainly composed of two distinct lineages, the basal and luminal cells. Because of the limitation of traditional transcriptome analysis of bulk mammary cells, the hierarchy and heterogeneity of mammary cells within these two lineages remain unclear. To this end, using single-cell RNA-Seq coupled with FACS analysis and principal component analysis, we determined gene expression profiles of mammary epithelial cells of virgin and pregnant mice. These analyses revealed a much higher heterogeneity among the mammary cells than has been previously reported and enabled cell classification into distinct subgroups according to signature gene markers present in each group. We also identified and verified a rare CDH5 + cell subpopulation within a basal cell lineage as quiescent mammary stem cells (MaSCs). Moreover, using pseudo-temporal analysis, we reconstructed the developmental trajectory of mammary epithelia and uncovered distinct changes in gene expression and in biological functions of mammary cells along the developmental process. In conclusion, our work greatly refines the resolution of the cellular hierarchy in developing mammary tissues. The discovery of CDH5 + cells as MaSCs in these tissues may have implications for our understanding of the initiation, development, and pathogenesis of mammary tumors. © 2018 Sun et al.

Human ear detection in the thermal infrared spectrum

NASA Astrophysics Data System (ADS)

Abaza, Ayman; Bourlai, Thirimachos

2012-06-01

In this paper the problem of human ear detection in the thermal infrared (IR) spectrum is studied in order to illustrate the advantages and limitations of the most important steps of ear-based biometrics that can operate in day and night time environments. The main contributions of this work are two-fold: First, a dual-band database is assembled that consists of visible and thermal profile face images. The thermal data was collected using a high definition middle-wave infrared (3-5 microns) camera that is capable of acquiring thermal imprints of human skin. Second, a fully automated, thermal imaging based ear detection method is developed for real-time segmentation of human ears in either day or night time environments. The proposed method is based on Haar features forming a cascaded AdaBoost classifier (our modified version of the original Viola-Jones approach1 that was designed to be applied mainly in visible band images). The main advantage of the proposed method, applied on our profile face image data set collected in the thermal-band, is that it is designed to reduce the learning time required by the original Viola-Jones method from several weeks to several hours. Unlike other approaches reported in the literature, which have been tested but not designed to operate in the thermal band, our method yields a high detection accuracy that reaches ~ 91.5%. Further analysis on our data set yielded that: (a) photometric normalization techniques do not directly improve ear detection performance. However, when using a certain photometric normalization technique (CLAHE) on falsely detected images, the detection rate improved by ~ 4%; (b) the high detection accuracy of our method did not degrade when we lowered down the original spatial resolution of thermal ear images. For example, even after using one third of the original spatial resolution (i.e. ~ 20% of the original computational time) of the thermal profile face images, the high ear detection accuracy of our method

Torsion of partial cleft of ear lobule.

PubMed

Kumaraswamy, M; Waiker, Veena P

2014-02-01

Torsion is a well-known phenomenon involving organs with long mesentery. Torsion in the ear lobule is rare. Ear lobule is very well vascularized. In cases of partial cleft ear lobule, there is a small segment of lobule inferior to the cleft which is vascularized through the pedicles on either side of the cleft. A lady aged 89 years presented with discoloration of the ear lobule. She was diagnosed as having gangrene of the central part of lobule. The segment of the lobule had undergone more than 360° torsion. She underwent debridement of gangrenous part and lobuloplasty. In our case laxity of the stretched lobule caused the torsion of the segment followed by gangrene. This rare complication indicates the need for correction of the cleft lobule not only for esthetic purpose, but also for the prevention of torsion. Copyright © 2013 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

Middle ear abnormalities in Van Maldergem syndrome.

PubMed

Verheij, Emmy; Thomeer, Henricus G X M; Pameijer, Frank A; Topsakal, Vedat

2017-01-01

Van Maldergem syndrome (VMS) is a very rare syndrome that was first described in 1992. The main features of this syndrome comprise intellectual disability, blepharo-naso-facial malformation, and hand anomalies. Almost all nine described patients have been shown to be affected by conductive hearing impairment attributed to microtia, and atresia of the outer ear canal. Here, we present a VMS patient with congenital malformations of the middle ear as the main reason for severe conductive bilateral hearing impairment. To our knowledge, this is the first report to describe middle ear abnormalities in VMS. These malformations were seen on high resolution Computed Tomography scanning and during an exploratory tympanotomy. Due to the severity of the middle ear abnormalities and the risk for facial nerve damage, the patient was not offered an ossicular chain reconstruction but a bone conduction device after this exploratory tympanotomy. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Desmoplakin II expression is not restricted to stratified epithelia.

PubMed

Angst, B D; Nilles, L A; Green, K J

1990-10-01

Desmosomes are major intercellular junctions found in association with intermediate filaments in epithelial, cardiac and arachnoidal tissue. Desmoplakins I and II (DPI and II) are highly related proteins localized in the innermost part of the desmosomal plaque and are candidates for linking intermediate filaments (IF) to the desmosomal complex. While investigators agree that DPI is present in all epithelia, they disagree on the distribution of DPII. Some have reported DPII to be restricted to stratified tissue and have furthermore suggested that the expression of DPII may be linked to stratification. We have compared the expression of DPI and II at the mRNA and protein levels in cell lines derived from simple, transitional and stratified epithelia. Northern blot analysis revealed DPI and II mRNA to be present in all cell lines as well as simple and stratified epithelial tissues. However, DPII mRNA could not be detected in cardiac muscle tissue. Immunoblotting and immunoprecipitation demonstrated the presence of DPI and II in all cell lines at the whole-cell protein level as well as in association with cytoskeletal fractions. Immunofluorescence staining was used to correlate the biochemical findings with the localization of DPI and II. While most cell lines exhibited typical intercellular and in many cases cytoplasmic DP staining, T24 cells exhibited predominantly diffuse and dotty cytoplasmic staining. In addition, we investigated whether changes in DPI and II expression occurred following calcium-induced cell contact formation and stratification in the human pharyngeal cell line, FaDu. No significant changes in mRNA or whole-cell protein levels were observed during a period of 5 days following the calcium switch. However, immunoblotting revealed a significant increase in DPI and II levels in the insoluble protein pool during desmosome formation. These observations indicated a possible recruitment of soluble DPI/II into an insoluble pool after induction of

Responses to Cell Loss Become Restricted as the Supporting Cells in Mammalian Vestibular Organs Grow Thick Junctional Actin Bands That Develop High Stability

PubMed Central

Burns, Joseph C.

2014-01-01

Sensory hair cell (HC) loss is a major cause of permanent hearing and balance impairments for humans and other mammals. Yet, fish, amphibians, reptiles, and birds readily replace HCs and recover from such sensory deficits. It is unknown what prevents replacement in mammals, but cell replacement capacity declines contemporaneously with massive postnatal thickening of F-actin bands at the junctions between vestibular supporting cells (SCs). In non-mammals, SCs can give rise to regenerated HCs, and the bands remain thin even in adults. Here we investigated the stability of the F-actin bands between SCs in ears from chickens and mice and Madin-Darby canine kidney cells. Pharmacological experiments and fluorescence recovery after photobleaching (FRAP) of SC junctions in utricles from mice that express a γ-actin–GFP fusion protein showed that the thickening F-actin bands develop increased resistance to depolymerization and exceptional stability that parallels a sharp decline in the cell replacement capacity of the maturing mammalian ear. The FRAP recovery rate and the mobile fraction of γ-actin–GFP both decreased as the bands thickened with age and became highly stabilized. In utricles from neonatal mice, time-lapse recordings in the vicinity of dying HCs showed that numerous SCs change shape and organize multicellular actin purse strings that reseal the epithelium. In contrast, adult SCs appeared resistant to deformation, with resealing responses limited to just a few neighboring SCs that did not form purse strings. The exceptional stability of the uniquely thick F-actin bands at the junctions of mature SCs may play an important role in restricting dynamic repair responses in mammalian vestibular epithelia. PMID:24478379

Responses to cell loss become restricted as the supporting cells in mammalian vestibular organs grow thick junctional actin bands that develop high stability.

PubMed

Burns, Joseph C; Corwin, Jeffrey T

2014-01-29

Sensory hair cell (HC) loss is a major cause of permanent hearing and balance impairments for humans and other mammals. Yet, fish, amphibians, reptiles, and birds readily replace HCs and recover from such sensory deficits. It is unknown what prevents replacement in mammals, but cell replacement capacity declines contemporaneously with massive postnatal thickening of F-actin bands at the junctions between vestibular supporting cells (SCs). In non-mammals, SCs can give rise to regenerated HCs, and the bands remain thin even in adults. Here we investigated the stability of the F-actin bands between SCs in ears from chickens and mice and Madin-Darby canine kidney cells. Pharmacological experiments and fluorescence recovery after photobleaching (FRAP) of SC junctions in utricles from mice that express a γ-actin-GFP fusion protein showed that the thickening F-actin bands develop increased resistance to depolymerization and exceptional stability that parallels a sharp decline in the cell replacement capacity of the maturing mammalian ear. The FRAP recovery rate and the mobile fraction of γ-actin-GFP both decreased as the bands thickened with age and became highly stabilized. In utricles from neonatal mice, time-lapse recordings in the vicinity of dying HCs showed that numerous SCs change shape and organize multicellular actin purse strings that reseal the epithelium. In contrast, adult SCs appeared resistant to deformation, with resealing responses limited to just a few neighboring SCs that did not form purse strings. The exceptional stability of the uniquely thick F-actin bands at the junctions of mature SCs may play an important role in restricting dynamic repair responses in mammalian vestibular epithelia.

Measurement in Sensory Modulation: The Sensory Processing Scale Assessment

PubMed Central

Miller, Lucy J.; Sullivan, Jillian C.

2014-01-01

OBJECTIVE. Sensory modulation issues have a significant impact on participation in daily life. Moreover, understanding phenotypic variation in sensory modulation dysfunction is crucial for research related to defining homogeneous groups and for clinical work in guiding treatment planning. We thus evaluated the new Sensory Processing Scale (SPS) Assessment. METHOD. Research included item development, behavioral scoring system development, test administration, and item analyses to evaluate reliability and validity across sensory domains. RESULTS. Items with adequate reliability (internal reliability >.4) and discriminant validity (p < .01) were retained. Feedback from the expert panel also contributed to decisions about retaining items in the scale. CONCLUSION. The SPS Assessment appears to be a reliable and valid measure of sensory modulation (scale reliability >.90; discrimination between group effect sizes >1.00). This scale has the potential to aid in differential diagnosis of sensory modulation issues. PMID:25184464

ChR2 transgenic animals in peripheral sensory system: Sensing light as various sensations.

PubMed

Ji, Zhi-Gang; Wang, Hongxia

2016-04-01

Since the introduction of Channelrhodopsin-2 (ChR2) to neuroscience, optogenetics technology was developed, making it possible to activate specific neurons or circuits with spatial and temporal precision. Various ChR2 transgenic animal models have been generated and are playing important roles in revealing the mechanisms of neural activities, mapping neural circuits, controlling the behaviors of animals as well as exploring new strategy for treating the neurological diseases in both central and peripheral nervous system. An animal including humans senses environments through Aristotle's five senses (sight, hearing, smell, taste and touch). Usually, each sense is associated with a kind of sensory organ (eyes, ears, nose, tongue and skin). Is it possible that one could hear light, smell light, taste light and touch light? When ChR2 is targeted to different peripheral sensory neurons by viral vectors or generating ChR2 transgenic animals, the animals can sense the light as various sensations such as hearing, touch, pain, smell and taste. In this review, we focus on ChR2 transgenic animals in the peripheral nervous system. Firstly the working principle of ChR2 as an optogenetic actuator is simply described. Then the current transgenic animal lines where ChR2 was expressed in peripheral sensory neurons are presented and the findings obtained by these animal models are reviewed. Copyright © 2016 Elsevier Inc. All rights reserved.

15 CFR 734.2 - Important EAR terms and principles.

Code of Federal Regulations, 2010 CFR

2010-01-01

... technology and software not subject to the EAR are described in §§ 734.7 through 734.11 and supplement no. 1... of items subject to the EAR out of the United States, or release of technology or software subject to... source code and object code software subject to the EAR. (2) Export of technology or software. (See...

15 CFR 734.2 - Important EAR terms and principles.

Code of Federal Regulations, 2012 CFR

2012-01-01

... technology and software not subject to the EAR are described in §§ 734.7 through 734.11 and supplement no. 1... of items subject to the EAR out of the United States, or release of technology or software subject to... source code and object code software subject to the EAR. (2) Export of technology or software. (See...

15 CFR 734.2 - Important EAR terms and principles.

Code of Federal Regulations, 2014 CFR

2014-01-01

... technology and software not subject to the EAR are described in §§ 734.7 through 734.11 and supplement no. 1... of items subject to the EAR out of the United States, or release of technology or software subject to... source code and object code software subject to the EAR. (2) Export of technology or software. (See...

15 CFR 734.2 - Important EAR terms and principles.

Code of Federal Regulations, 2013 CFR

2013-01-01

... technology and software not subject to the EAR are described in §§ 734.7 through 734.11 and supplement no. 1... of items subject to the EAR out of the United States, or release of technology or software subject to... source code and object code software subject to the EAR. (2) Export of technology or software. (See...

15 CFR 734.2 - Important EAR terms and principles.

Code of Federal Regulations, 2011 CFR

2011-01-01

... technology and software not subject to the EAR are described in §§ 734.7 through 734.11 and supplement no. 1... of items subject to the EAR out of the United States, or release of technology or software subject to... source code and object code software subject to the EAR. (2) Export of technology or software. (See...

Ear Aesthetics: Investigation by the Use of an Online Viral Survey.

PubMed

Steele, Jessica; Farmer, Eleanor; O'Hara, Justine; Bulstrode, Neil

2017-03-01

The ear is a key facial feature and yet few studies have previously assessed ear aesthetics. This study aimed to assess the anatomical components of the ear that have the greatest impact on the perception of ear aesthetics. Three photographs of a male adult ear (close-up, lateral, posterior) were digitally manipulated such that in each, 1 anatomical element of the ear was either enlarged or reduced. A complete set of 16 photographs including a repeat of the original ear as a control were randomized and entered into an online survey that required respondents to rate the attractiveness of each ear on a scale of 1 (least attractive) to 10 (most attractive). The survey was disseminated using email and social media. A total of 248 responses were received, 155 women and 92 men. Respondents were grouped by demographics of age and occupation. Reducing (R) or enlarging (E) the helix (R, P = 0.0256; E, P = 0.003), concha (R, P = 0.0002; E, P = <0.0001) and lobule (R, P = 0.0006; E, P < 0.0001) had a significant effect on ratings of attractiveness. Altering the tragus had no significant effect (R, P = 0.448; E, P = 0.201). In lateral view, raising the height of the ear had a significant effect (P = <0.0001) but not in lowering the height (P = 0.3038). Increasing and decreasing the projection of the ears both had a significant effect (P < 0.0001). The results of this study have provided useful evidence regarding the anatomical components of the ear that have the greatest effect on ear aesthetics. Furthermore, this study has proven the usefulness of conducting research using viral online surveys.

Malformation of stria vascularis in the developing inner ear of the German waltzing guinea pig.

PubMed

Jin, Zhe; Mannström, Paula; Järlebark, Leif; Ulfendahl, Mats

2007-05-01

Auditory function and cochlear morphology have previously been described in the postnatal German waltzing guinea pig, a strain with recessive deafness. In the present study, cochlear histopathology was further investigated in the inner ear of the developing German waltzing guinea pig (gw/gw). The lumen of the cochlear duct diminished progressively from embryonic day (E) 35 to E45 and was absent at E50 because of the complete collapse of Reissner's membrane onto the hearing organ. The embryonic stria vascularis, consisting of a simple epithelium, failed to transform into the complex trilaminar tissue seen in normal animals and displayed signs of degeneration. Subsequent degeneration of the sensory epithelium was observed from E50 and onwards. Defective and insufficient numbers of melanocytes were observed in the developing gw/gw stria vascularis. A gene involved in cochlear melanocyte development, Pax3, was markedly reduced in lateral wall tissue of the cochlea of both E40 and adult gw/gw individuals, whereas its expression was normal in the skin and diaphragm muscle of adult gw/gw animals. The Pax3 gene may thus be involved in the pathological process but is unlikely to be the primary mutated gene in the German waltzing guinea pig. TUNEL assay showed no signs of apoptotic cell death in the developing stria vascularis of this type of guinea pig. Thus, malformation of the stria vascularis appears to be the primary defect in the inner ear of the German waltzing guinea pig. Defective and insufficient numbers of melanocytes might migrate to the developing stria vascularis but fail to provide the proper support for the subsequent development of marginal and basal cells, thereby leading to stria vascularis malformation and dysfunction in the inner ear of the German waltzing guinea pig.

Mozart Ear Deformity: a Rare Diagnosis in the Ear Reconstruction Clinic.

PubMed

Telich-Tarriba, Jose E; Victor-Baldin, Andre; Apellaniz-Campo, Armando

2017-07-01

Mozart ear is a rare auricular deformity; clinically the auricle is characterized by the bulging appearance of the anterosuperior portion of the auricle due to fusion of the crura of the antihelix, an inversion in the normal form of the cavum conchae resulting in its convexity and a slit-like narrowing of the orifice of the external auditory meatus.A retrospective review of clinical and photographic records of patients attended at the ear reconstruction clinic of our hospital between June of 2010 and May 2016 was performed; out of 576 consecutive patients only 3 fulfilled the inclusion criteria, with a prevalence of 0.5%. The authors present these patients.Surgical interventions mainly focus on the correction of the convex concha; however, the procedure should be tailored to the severity of the deformity and the wishes of the patient.

Molecular bases of K+ secretory cells in the inner ear: shared and distinct features between birds and mammals

PubMed Central

Wilms, Viviane; Köppl, Christine; Söffgen, Chris; Hartmann, Anna-Maria; Nothwang, Hans Gerd

2016-01-01

In the cochlea, mammals maintain a uniquely high endolymphatic potential (EP), which is not observed in other vertebrate groups. However, a high [K+] is always present in the inner ear endolymph. Here, we show that Kir4.1, which is required in the mammalian stria vascularis to generate the highly positive EP, is absent in the functionally equivalent avian tegmentum vasculosum. In contrast, the molecular repertoire required for K+ secretion, specifically NKCC1, KCNQ1, KCNE1, BSND and CLC-K, is shared between the tegmentum vasculosum, the vestibular dark cells and the marginal cells of the stria vascularis. We further show that in barn owls, the tegmentum vasculosum is enlarged and a higher EP (~+34 mV) maintained, compared to other birds. Our data suggest that both the tegmentum vasculosum and the stratified stria vascularis evolved from an ancestral vestibular epithelium that already featured the major cell types of the auditory epithelia. Genetic recruitment of Kir4.1 specifically to strial melanocytes was then a crucial step in mammalian evolution enabling an increase in the cochlear EP. An increased EP may be related to high-frequency hearing, as this is a hallmark of barn owls among birds and mammals among amniotes. PMID:27680950

[An ear thermometer based on infrared thermopiles sensor].

PubMed

Xie, Haiyuan; Qian, Mingli

2013-09-01

According to the development of body temperature measurement mode, an ear thermometer with infrared thermopiles sensor is designed for body thermometry Compared with oral thermometer, the accuracy of ear thermometer is acceptable.

Correction of Lying Ears by Augmentation of the Conchoscaphal Angle.

PubMed

Kim, Sung-Eun; Yeo, Chi-Ho; Kim, Taegon; Kim, Yong-Ha; Lee, Jun Ho; Chung, Kyu-Jin

2017-01-01

Lying ears are defined as ears that protrude less from the head, and in frontal view, are characterized by lateral positioning of antihelical contour relative to the helical rim. These aesthetically displeasing ears require correction in accord with the goals of otoplasty stated by McDowell. The authors present a case of lying ears treated by correcting the conchomastoid angle using Z-plasty, resection of posterior auricular muscle, and correction of the conchoscaphal angle by releasing cartilage using 2 full-thickness incisions and grafting of a conchal cartilage spacer. By combining these techniques, the authors efficiently corrected lying ears and produced aesthetically pleasing results.

Sonographic Measurement of Fetal Ear Length in Turkish Women with a Normal Pregnancy

PubMed Central

Özdemir, Mucize Eriç; Uzun, Işıl; Karahasanoğlu, Ayşe; Aygün, Mehmet; Akın, Hale; Yazıcıoğlu, Fehmi

2014-01-01

Background: Abnormal fetal ear length is a feature of chromosomal disorders. Fetal ear length measurement is a simple measurement that can be obtained during ultrasonographic examinations. Aims: To develop a nomogram for fetal ear length measurements in our population and investigate the correlation between fetal ear length, gestational age, and other standard fetal biometric measurements. Study Design: Cohort study. Methods: Ear lengths of the fetuses were measured in normal singleton pregnancies. The relationship between gestational age and fetal ear length in millimetres was analysed by simple linear regression. In addition, the correlation of fetal ear length measurements with biparietal diameter, head circumference, abdominal circumference, and femur length were evaluated.Ear length measurements were obtained from fetuses in 389 normal singleton pregnancies ranging between 16 and 28 weeks of gestation. Results: A nomogram was developed by linear regression analysis of the parameters ear length and gestational age. Fetal ear length (mm) = y = (1.348 X gestational age)−12.265), where gestational ages is in weeks. A high correlation was found between fetal ear length and gestational age, and a significant correlation was also found between fetal ear length and the biparietal diameter (r=0.962; p<0.001). Similar correlations were found between fetal ear length and head circumference, and fetal ear length and femur length. Conclusion: The results of this study provide a nomogram for fetal ear length. The study also demonstrates the relationship between ear length and other biometric measurements. PMID:25667783

a Middle-Ear Reverse Transfer Function Computed from Vibration Measurements of Otoacoustic Emissions on the Ear Drum of the Guinea PIG

NASA Astrophysics Data System (ADS)

Dalhoff, Ernst; Turcanu, Diana; Gummer, Anthony W.

2009-02-01

Using distortion products measured as vibration of the umbo and as sound pressure in the ear canal of guinea pigs, we calculated the corresponding reverse transfer function. We compare the measurements with a middle-ear model taken from the literature and adapted to the guinea pig. A reasonable fit could be achieved. We conclude that the reverse transfer function will be useful to aid fitting a middle-ear model to measured transfer functions of human subjects.

Toll-Like Receptor 4 Engagement Mediates Prolyl Endopeptidase Release from Airway Epithelia via Exosomes.

PubMed

Szul, Tomasz; Bratcher, Preston E; Fraser, Kyle B; Kong, Michele; Tirouvanziam, Rabindra; Ingersoll, Sarah; Sztul, Elizabeth; Rangarajan, Sunil; Blalock, J Edwin; Xu, Xin; Gaggar, Amit

2016-03-01

Proteases are important regulators of pulmonary remodeling and airway inflammation. Recently, we have characterized the enzyme prolyl endopeptidase (PE), a serine peptidase, as a critical protease in the generation of the neutrophil chemoattractant tripeptide Pro-Gly-Pro (PGP) from collagen. However, PE has been characterized as a cytosolic enzyme, and the mechanism mediating PE release extracellularly remains unknown. We examined the role of exosomes derived from airway epithelia as a mechanism for PE release and the potential extracellular signals that regulate the release of these exosomes. We demonstrate a specific regulatory pathway of exosome release from airway epithelia and identify PE as novel exosome cargo. LPS stimulation of airway epithelial cells induces release of PE-containing exosomes, which is significantly attenuated by small interfering RNA depletion of Toll-like receptor 4 (TLR4). These differences were recapitulated upon intratracheal LPS administration in mice competent versus deficient for TLR4 signaling. Finally, sputum samples from subjects with cystic fibrosis colonized with Pseudomonas aeruginosa demonstrate elevated exosome content and increased PE levels. This TLR4-based mechanism highlights the first report of nonstochastic release of exosomes in the lung and couples TLR4 activation with matrikine generation. The increased quantity of these proteolytic exosomes in the airways of subjects with chronic lung disease highlights a new mechanism of injury and inflammation in the pathogenesis of pulmonary disorders.

Requirement for Lmo4 in the Vestibular Morphogenesis of Mouse Inner Ear

PubMed Central

Deng, Min; Pan, Ling; Xie, Xiaoling; Gan, Lin

2009-01-01

During development, compartmentalization of an early embryonic structure produces blocks of cells with distinct properties and developmental potentials. The auditory and vestibular components of vertebrate inner ears are derived from defined compartments within the otocyst during embryogenesis. The vestibular apparatus, including three semicircular canals, saccule, utricle, and their associated sensory organs, detects angular and linear acceleration of the head and relays the information through vestibular neurons to vestibular nuclei in the brainstem. How the early developmental events manifest vestibular structures at the molecular level is largely unknown. Here, we show that LMO4, a LIM-domain-only transcriptional regulator, is required for the formation of semicircular canals and their associated sensory cristae. Targeted disruption of Lmo4 resulted in the dysmorphogenesis of the vestibule and in the absence of three semicircular canals, anterior and posterior cristae. In Lmo4-null otocysts, canal outpouches failed to form and cell proliferation was reduced in the dorsolateral region. Expression analysis of the known otic markers showed that Lmo4 is essential for the normal expression of Bmp4, Fgf10, Msx1, Isl1, Gata3, and Dlx5 in the dorsolateral domain of the otocyst, whereas the initial compartmentalization of the otocyst remains unaffected. Our results demonstrate that Lmo4 controls the development of the dorsolateral otocyst into semicircular canals and cristae through two distinct mechanisms: regulating the expression of otic specific genes and stimulating the proliferation of the dorsolateral part of the otocyst. PMID:19913004

Two stage ear/microtia reconstruction using costal cartilage.

PubMed

Balaji, S M

2015-01-01

Reconstruction of Grade III microtia is a challenging entity in maxillofacial esthetic rehabilitation. Several advocacies and philosophies exist in this field. The aim of the manuscript is to present a single South Indian Experience with Ear reconstruction among South Indian Population. Retrospective analysis of unilateral Grade III microtia reconstruction was performed. Using a set of predefined inclusion and exclusion criteria, the population was selected. Outcome measures in terms of the ear size, auriculocephalic angle, and the conchal depth were measured in the reconstructed and normal side. Descriptive statistics is presented. Twenty-four patients formed the study group and had undergone the classical two-stage reconstruction in a similar fashion. The mean ear size in normal side was 65.8 ± 2.8 mm whereas on the reconstructed side, it was 61.3 ± 5.8 mm. The center's technique achieved above 75% similarity as that of the other normal ear. The mean auriculocephalic angle was 44.6 ± 5.2° whereas for the surgically reconstructed ear, it was 41.9 ± 2.6°. Overall, in these patients, we achieved a 79.94% similarity of auriculocephalic angle in the reconstructed ear as compared to the normal auricle. The conchal depth was 19.2 ± 2.1 mm and 16.6 ± 1.9 mm for normal and reconstructed ear, respectively. In terms of conchal depth, the present study group showed an achievement of 82.88% of accuracy even after a prolonged follow-up. The center employs a classic two stage reconstruction with a customized prosthesis that helps to avoid the loss of projection geometry and minimizes adhesion, infection, and early loss of structural stability.

An in vitro model of murine middle ear epithelium.

PubMed

Mulay, Apoorva; Akram, Khondoker M; Williams, Debbie; Armes, Hannah; Russell, Catherine; Hood, Derek; Armstrong, Stuart; Stewart, James P; Brown, Steve D M; Bingle, Lynne; Bingle, Colin D

2016-11-01

Otitis media (OM), or middle ear inflammation, is the most common paediatric disease and leads to significant morbidity. Although understanding of underlying disease mechanisms is hampered by complex pathophysiology it is clear that epithelial abnormalities underpin the disease. There is currently a lack of a well-characterised in vitro model of the middle ear (ME) epithelium that replicates the complex cellular composition of the middle ear. Here, we report the development of a novel in vitro model of mouse middle ear epithelial cells (mMECs) at an air-liquid interface (ALI) that recapitulates the characteristics of the native murine ME epithelium. We demonstrate that mMECs undergo differentiation into the varied cell populations seen within the native middle ear. Proteomic analysis confirmed that the cultures secrete a multitude of innate defence proteins from their apical surface. We showed that the mMECs supported the growth of the otopathogen, nontypeable Haemophilus influenzae (NTHi), suggesting that the model can be successfully utilised to study host-pathogen interactions in the middle ear. Overall, our mMEC culture system can help to better understand the cell biology of the middle ear and improve our understanding of the pathophysiology of OM. The model also has the potential to serve as a platform for validation of treatments designed to reverse aspects of epithelial remodelling that underpin OM development. © 2016. Published by The Company of Biologists Ltd.

Vision impairment and dual sensory problems in middle age

PubMed Central

Dawes, Piers; Dickinson, Christine; Emsley, Richard; Bishop, Paul; Cruickshanks, Karen; Edmondson-Jones, Mark; McCormack, Abby; Fortnum, Heather; Moore, David R.; Norman, Paul; Munro, Kevin

2014-01-01

Purpose Vision and hearing impairments are known to increase in middle age. In this study we describe the prevalence of vision impairment and dual sensory impairment in UK adults aged 40 to 69 years in a very large and recently ascertained data set. The associations between vision impairment, age, sex, socioeconomic status, and ethnicity are reported. Methods This research was conducted using the UK Biobank Resource, with subsets of UK Biobank data analysed with respect to self-report of eye problems and glasses use. Better-eye visual acuity with habitually worn refractive correction was assessed with a logMAR chart (n = 116,682). Better-ear speech reception threshold was measured with an adaptive speech in noise test, the Digit Triplet Test (n = 164,770). Prevalence estimates were weighted with respect to UK 2001 Census data. Results Prevalence of mild visual impairment and low vision was estimated at 15.2% (95% CI 14.9–15.5%) and 0.9% (95% CI 0.8–1.0%), respectively. Use of glasses was 88.0% (95% CI 87.9–88.1%). The prevalence of dual sensory impairment was 3.1% (95% CI 3.0–3.2%) and there was a nine-fold increase in the prevalence of dual sensory problems between the youngest and oldest age groups. Older adults, those from low socioeconomic and ethnic minority backgrounds were most at risk for vision problems. Conclusions Mild vision impairment is common in middle aged UK adults, despite widespread use of spectacles. Possible barriers to optometric care for those from low socioeconomic and ethnic minority backgrounds may require attention. A higher than expected prevalence of dual impairment suggests that hearing and vision problems share common causes. Optometrists should consider screening for hearing problems, particularly among older adults. PMID:24888710

Are two ears not better than one?

PubMed

McArdle, Rachel A; Killion, Mead; Mennite, Monica A; Chisolm, Theresa H

2012-03-01

The decision to fit one or two hearing aids in individuals with binaural hearing loss has been debated for years. Although some 78% of U.S. hearing aid fittings are binaural (Kochkin , 2010), Walden and Walden (2005) presented data showing that 82% (23 of 28 patients) of their sample obtained significantly better speech recognition in noise scores when wearing one hearing aid as opposed to two. To conduct two new experiments to fuel the monaural/binaural debate. The first experiment was a replication of Walden and Walden (2005), whereas the second experiment examined the use of binaural cues to improve speech recognition in noise. A repeated measures experimental design. Twenty veterans (aged 59-85 yr), with mild to moderately severe binaurally symmetrical hearing loss who wore binaural hearing aids were recruited from the Audiology Department at the Bay Pines VA Healthcare System. Experiment 1 followed the procedures of the Walden and Walden study, where signal-to-noise ratio (SNR) loss was measured using the Quick Speech-in-Noise (QuickSIN) test on participants who were aided with their current hearing aids. Signal and noise were presented in the sound booth at 0° azimuth under five test conditions: (1) right ear aided, (2) left ear aided, (3) both ears aided, (4) right ear aided, left ear plugged, and (5) unaided. The opposite ear in (1) and (2) was left open. In Experiment 2, binaural Knowles Electronics Manikin for Acoustic Research (KEMAR) manikin recordings made in Lou Malnati's pizza restaurant during a busy period provided a typical real-world noise, while prerecorded target sentences were presented through a small loudspeaker located in front of the KEMAR manikin. Subjects listened to the resulting binaural recordings through insert earphones under the following four conditions: (1) binaural, (2) diotic, (3) monaural left, and (4) monaural right. Results of repeated measures ANOVAs demonstrated that the best speech recognition in noise performance was

Pediatric Obesity and Ear, Nose, and Throat Disorders

MedlinePlus

... Marketplace Find an ENT Doctor Near You Pediatric Obesity and Ear, Nose, and Throat Disorders Pediatric Obesity ... self-esteem, and isolation from their peers. Pediatric obesity and otolaryngic problems Otolaryngologists, or ear, nose, and ...