scholarly journals Histopathology of the Human Inner Ear in the p.L114P COCH Mutation (DFNA9)

2016 ◽  
Vol 21 (2) ◽  
pp. 88-97 ◽  
Author(s):  
Barbara J. Burgess ◽  
Jennifer T. O''Malley ◽  
Takefumi Kamakura ◽  
Kris Kristiansen ◽  
Nahid G. Robertson ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Inner Ear ◽  
Ganglion Cells ◽  
Spiral Ganglion ◽  
Clinical Findings ◽  
Spiral Ligament ◽  
Vestibular Disorder ◽  
Profound Hearing Loss ◽  
The Usa ◽  
Human Inner Ear

The histopathology of the inner ear in a patient with hearing loss caused by the p.L114P COCH mutation and its correlation with the clinical phenotype are presented. To date, 23 COCH mutations causative of DFNA9 autosomal dominant sensorineural hearing loss and vestibular disorder have been reported, and the histopathology of the human inner ear has been described in 4 of these. The p.L114P COCH mutation was first described in a Korean family. We have identified the same mutation in a family of non-Asian ancestry in the USA, and the temporal bone histopathology and clinical findings are presented herein. The histopathology found in the inner ear was similar to that shown in the 4 other COCH mutations and included degeneration of the spiral ligament with deposition of an eosinophilic acellular material, which was also found in the distal osseous spiral lamina, at the base of the spiral limbus, and in mesenchymal tissue at the base of the vestibular neuroepithelium. This is the first description of human otopathology of the COCH p.L114P mutation. In addition, it is the only case with otopathology characterization in an individual with any COCH mutation and residual hearing, thus allowing assessment of primary histopathological events in DFNA9, before progression to more profound hearing loss. A quantitative cytologic analysis of atrophy in this specimen and immunostaining using anti-neurofilament and anti-myelin protein zero antibodies confirmed that the principal histopathologic correlate of hearing loss was degeneration of the dendritic fibers of spiral ganglion cells in the osseous spiral lamina. The implications for cochlear implantation in this disorder are discussed.

scholarly journals Histopathology of the Human Inner Ear in Alström's Syndrome

2015 ◽  
Vol 20 (4) ◽  
pp. 267-272 ◽  
Author(s):  
Joseph B. Nadol Jr ◽  
Jan D. Marshall ◽  
Roderick T. Bronson
Keyword(s):  
Inner Ear ◽  
Autosomal Recessive ◽  
Ganglion Cells ◽  
Stria Vascularis ◽  
Genetic Disorder ◽  
Spiral Ganglion ◽  
Organ Of Corti ◽  
Outer Hair Cells ◽  
Spiral Ligament ◽  
Human Inner Ear

Alström's syndrome is an autosomal recessive syndromic genetic disorder caused by mutations in the ALMS1 gene. Sensorineural hearing loss occurs in greater than 85% of patients. Histopathology of the inner ear abnormalities in the human has not previously been fully described. Histopathology of the inner ear in Alström's syndrome is presented in 2 genetically confirmed cases. The predominant histopathologic correlates of the sensorineural loss were degeneration of the organ of Corti, both inner and outer hair cells, degeneration of spiral ganglion cells, and atrophy of the stria vascularis and spiral ligament.

scholarly journals Intrinsically Self-renewing Neuroprogenitors From the A/J Mouse Spiral Ganglion as Virtually Unlimited Source of Mature Auditory Neurons

2020 ◽  
Vol 14 ◽  
Author(s):  
Francis Rousset ◽  
Vivianne B. C. Kokje ◽  
Rebecca Sipione ◽  
Dominik Schmidbauer ◽  
German Nacher-Soler ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Inner Ear ◽  
Progenitor Cells ◽  
Ganglion Cells ◽  
Spiral Ganglion ◽  
Specific Cell ◽  
Auditory Neurons ◽  
Self Renewal ◽  
Starting Point ◽  
Ganglion Neurons

Nearly 460 million individuals are affected by sensorineural hearing loss (SNHL), one of the most common human sensory disorders. In mammals, hearing loss is permanent due to the lack of efficient regenerative capacity of the sensory epithelia and spiral ganglion neurons (SGN). Sphere-forming progenitor cells can be isolated from the mammalian inner ear and give rise to inner ear specific cell types in vitro. However, the self-renewing capacities of auditory progenitor cells from the sensory and neuronal compartment are limited to few passages, even after adding powerful growth factor cocktails. Here, we provide phenotypical and functional characterization of a new pool of auditory progenitors as sustainable source for sphere-derived auditory neurons. The so-called phoenix auditory neuroprogenitors, isolated from the A/J mouse spiral ganglion, exhibit robust intrinsic self-renewal properties beyond 40 passages. At any passage or freezing–thawing cycle, phoenix spheres can be efficiently differentiated into mature spiral ganglion cells by withdrawing growth factors. The differentiated cells express both neuronal and glial cell phenotypic markers and exhibit similar functional properties as mouse spiral ganglion primary explants and human sphere-derived spiral ganglion cells. In contrast to other rodent models aiming at sustained production of auditory neurons, no genetic transformation of the progenitors is needed. Phoenix spheres therefore represent an interesting starting point to further investigate self-renewal in the mammalian inner ear, which is still far from any clinical application. In the meantime, phoenix spheres already offer an unlimited source of mammalian auditory neurons for high-throughput screens while substantially reducing the numbers of animals needed.

Scala Vestibuli Partition with Deafness and Renal Disease

1973 ◽  
Vol 82 (6) ◽  
pp. 871-875 ◽  
Author(s):  
Ruth Gussen
Keyword(s):  
Hearing Loss ◽  
Renal Disease ◽  
Immunosuppressive Therapy ◽  
Ganglion Cells ◽  
Chronic Renal Disease ◽  
Spiral Ganglion ◽  
Spiral Ligament ◽  
Cochlear Hearing Loss ◽  
The Brain ◽  
Scala Vestibuli

Spiral ligament projections, partitioning the beginning of the scala vestibuli, bilaterally, were demonstrated in a patient with chronic renal disease, who had a bilateral midfrequency cochlear hearing loss. There were also spongy spiral ligament changes, strial atrophy and decreased spiral ganglion cells in the basal and middle cochlear turns. The patient was maintained on immunosuppressive therapy for four years after receiving a renal transplant. He died of a primary malignant lymphoma of the brain and cryptococcal meningitis, both probably related to immunosuppressive therapy.

scholarly journals Targeted Deletion of Loxl3 by Col2a1-Cre Leads to Progressive Hearing Loss

2021 ◽  
Vol 9 ◽  
Author(s):  
Ziyi Liu ◽  
Xinfeng Bai ◽  
Peifeng Wan ◽  
Fan Mo ◽  
Ge Chen ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Inner Ear ◽  
Essential Role ◽  
Basilar Membrane ◽  
Inflammatory Responses ◽  
Spiral Ganglion ◽  
Spiral Ligament ◽  
Progressive Hearing Loss ◽  
Secondary Degeneration ◽  
Ganglion Neurons

Collagens are major constituents of the extracellular matrix (ECM) that play an essential role in the structure of the inner ear and provide elasticity and rigidity when the signals of sound are received and transformed into electrical signals. LOXL3 is a member of the lysyl oxidase (LOX) family that are copper-dependent amine oxidases, generating covalent cross-links to stabilize polymeric elastin and collagen fibers in the ECM. Biallelic missense variant of LOXL3 was found in Stickler syndrome with mild conductive hearing loss. However, available information regarding the specific roles of LOXL3 in auditory function is limited. In this study, we showed that the Col2a1-Cre-mediated ablation of Loxl3 in the inner ear can cause progressive hearing loss, degeneration of hair cells and secondary degeneration of spiral ganglion neurons. The abnormal distribution of type II collagen in the spiral ligament and increased inflammatory responses were also found in Col2a1–Loxl3–/– mice. Amino oxidase activity exerts an effect on collagen; thus, Loxl3 deficiency was expected to result in the instability of collagen in the spiral ligament and the basilar membrane, which may interfere with the mechanical properties of the organ of Corti and induce the inflammatory responses that are responsible for the hearing loss. Overall, our findings suggest that Loxl3 may play an essential role in maintaining hearing function.

scholarly journals A Human Inner Ear Model for assessment of Noise Induced Hearing Loss via energy methods

2020 ◽  
Vol 53 (2) ◽  
pp. 16424-16429
Author(s):  
Milka C.I. Madahana ◽  
Otis T.C. Nyandoro ◽  
John E.D. Ekoru
Keyword(s):  
Hearing Loss ◽  
Inner Ear ◽  
Energy Methods ◽  
Noise Induced Hearing Loss ◽  
Human Inner Ear

Otologic Histopathology of Fabry's Disease

1989 ◽  
Vol 98 (5) ◽  
pp. 359-363 ◽  
Author(s):  
Patricia A. Schachern ◽  
Michael M. Paparella ◽  
Donald A. Shea ◽  
Tae H. Yoon
Keyword(s):  
Temporal Bone ◽  
Ganglion Cells ◽  
Spiral Ganglion ◽  
Cell Loss ◽  
The Body ◽  
Spiral Ligament ◽  
Fabry’S Disease ◽  
Fabry's Disease ◽  
Temporal Bones ◽  
Spiral Ganglia

Fabry's disease is a rare progressive X-linked recessive disorder of glycosphingolipid metabolism. The accumulation of glycosphingolipids occurs in virtually all areas of the body, including the endothelial, perithelial, and smooth-muscle cells of blood vessels, the ganglion cells of the autonomic nervous system, and the glomeruli and tubules of the kidney. Although otologic symptoms have been described in these patients, to our knowledge there have been no temporal bone histopathologic reports. We describe the clinical histories, audiometric results, and temporal bone findings of two patients with this rare disorder. Both patients demonstrated a bilateral sloping sensorineural hearing loss audiometrically. Middle ear findings of seropurulent effusions and hyperplastic mucosa were seen in all four temporal bones. Strial and spiral ligament atrophy in all turns, and hair cell loss mainly in the basal turns, were also common findings. The number of spiral ganglion cells was reduced in all temporal bones; however, evidence of glycosphingolipid accumulation was not observed in the spiral ganglia.

Cytomegalovirus Isolation from a Human Inner Ear

1979 ◽  
Vol 88 (3) ◽  
pp. 424-426 ◽  
Author(s):  
Larry E. Davis ◽  
Charles G. James ◽  
Frederick Fiber ◽  
Leroy C. McLaren
Keyword(s):  
Hearing Loss ◽  
Inner Ear ◽  
Congenital Deafness ◽  
Cmv Infection ◽  
Human Inner Ear ◽  
Congenital Cmv

Cytomegalovirus (CMV) infection of the fetus has been associated with congenital deafness or hearing loss. This association has previously been based on clinical or pathological studies. We report an infant who died with the congenital CMV syndrome in which CMV was isolated from the perilymph of the inner ear providing additional evidence that this virus can infect the labyrinth.

Brn3a is a transcriptional regulator of soma size, target field innervation and axon pathfinding of inner ear sensory neurons

Development ◽  
2001 ◽  
Vol 128 (13) ◽  
pp. 2421-2432 ◽  
Author(s):  
Eric J. Huang ◽  
Wei Liu ◽  
Bernd Fritzsch ◽  
Lynne M. Bianchi ◽  
Louis F. Reichardt ◽  
...  
Keyword(s):  
Inner Ear ◽  
Ganglion Cells ◽  
Substantial Reduction ◽  
Spiral Ganglion ◽  
Neurotrophin Receptor ◽  
Axon Pathfinding ◽  
Target Field ◽  
Afferent Fibers ◽  
Soma Size ◽  
Ganglion Neurons

The POU domain transcription factors Brn3a, Brn3b and Brn3c are required for the proper development of sensory ganglia, retinal ganglion cells, and inner ear hair cells, respectively. We have investigated the roles of Brn3a in neuronal differentiation and target innervation in the facial-stato-acoustic ganglion. We show that absence of Brn3a results in a substantial reduction in neuronal size, abnormal neuronal migration and downregulation of gene expression, including that of the neurotrophin receptor TrkC, parvalbumin and Brn3b. Selective loss of TrkC neurons in the spiral ganglion of Brn3a−/− cochlea leads to an innervation defect similar to that of TrkC−/− mice. Most remarkably, our results uncover a novel role for Brn3a in regulating axon pathfinding and target field innervation by spiral and vestibular ganglion neurons. Loss of Brn3a results in severe retardation in development of the axon projections to the cochlea and the posterior vertical canal as early as E13.5. In addition, efferent axons that use the afferent fibers as a scaffold during pathfinding also show severe misrouting. Interestingly, despite the well-established roles of ephrins and EphB receptors in axon pathfinding, expression of these molecules does not appear to be affected in Brn3a−/− mice. Thus, Brn3a must control additional downstream genes that are required for axon pathfinding.

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