The blood labyrinthine barrier in the human normal and Meniere's disease macula utricle.

The ultrastructural organization of the blood labyrinthine barrier (BLB) was investigated in the human vestibular endorgan, the utricular macula, using postmortem specimens from individuals with documented normal auditory and vestibular function and surgical specimens from patients with intractable Meniere's disease. Transmission electron microscopic analysis of capillaries located in the normal human utricular stroma showed vascular endothelial cells with few pinocytotic vesicles, covered by a smooth and uniform basement membrane surrounded by pericyte processes. Meniere's disease specimens revealed differential ultrastructural pathological changes in the cellular elements of the microvasculature. With moderate degeneration of the BLB, there were numerous vesicles within the vascular endothelial cells (VECs), with increased numbers at the abluminal face, pericyte process detachment and disruption of the perivascular basement membrane surrounding the VECs. With severe degeneration of the BLB, there was severe vacuolization or frank apparent necrosis of VECs and loss of subcellular organelles. A higher severity of BLB degenerative changes was associated with a higher degree of basement membrane thickening and edematous changes within the vestibular stroma. This study presents the first ultrastructural analysis of the capillaries constituting the BLB in the human vestibular macula utricle from normal and Meniere's disease

Evaluation of 4 Outcomes Measures in Microtia Treatment: Exposures, Infections, Aesthetics, and Psychosocial Ramifications.

BackgroundIn craniofacial microsomia, microtia and canal atresia pose formidable reconstructive challenges. We review our institutional experience in treating microtia and atresia to identify variables associated with 4 outcomes measures: complications, surgical revisions, aesthetic outcomes, and psychosocial function.MethodsCraniofacial microsomia patients treated at the University of California Los Angeles Craniofacial Clinic between 2008 and 2014 greater than 13 years of age (n = 68) were reviewed for microtia and atresia treatment and outcomes.ResultsIn total, 91.2% of patients diagnosed with craniofacial microsomia presented with microtia, affecting 75 ears. Both a male and right-sided predominance were observed. Fifty-six patients (90.3%) underwent autologous external ear reconstruction at an average age of 8.5 years. Age, type of incision, and size of cartilage framework did not predict total number of surgeries or complications. Severity of ear anomalies correlated with increased number of surgeries (P < 0.001) and decreased aesthetic outcomes (P < 0.001) but not complications. In total, 87.1% of patients with microtia had documented hearing loss, of which the majority were conductive and 18.5% were mixed sensorineural and conductive. Hearing deficits were addressed in 70.4% of patients with external hearing aids, bone anchored hearing aids, or canaloplasty. Of all variables, improvement of psychosocial function was correlated only to hearing loss treatment of any type (P = 0.01).ConclusionsOn evaluation of surgical and patient characteristics, severity of microtia predicted the total number of surgical revisions performed and aesthetic ratings. In addition, we found that the only factor that correlated with improved patient and parent-reported psychosocial outcomes was treatment of hearing loss

Expression of Brain-Derived Neurotrophic Factor in Human Spiral Ganglia Neurons after Cochlear Implantation.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) is an important factor in the development and neuroprotection of afferent auditory pathways. In this study, we investigated the expression of BDNF in the afferent auditory pathway after cochlear implantation (CI), hypothesizing that electrical stimulation after CI stimulates BDNF expression in the afferent auditory pathway. METHODS: Archival human temporal bones from eight patients with a history of CI and five patients with normal hearing (ages 65-93 years old) were studied. Temporal bone specimens were immunoreacted with rabbit polyclonal antibodies against BDNF and mouse monoclonal antibodies against pan-neurofilaments. In cases of unilateral CI, the BDNF expression was compared with the contralateral unimplanted ear and normal temporal bones without hearing loss. RESULTS: BDNF immunoreactivity (IR) localized to the spiral ganglion neurons (SGNs) somata and the surrounding satellite cells. BDNF-IR in the spiral ganglia was similar in the apical, middle, and basal hook regions. Neurofilament IR localized to SGN nerve fibers in both implanted and unimplanted cochleae. BDNF-IR in the SGN and satellite cells was significantly increased in the implanted specimens compared with the unimplanted specimens ( p < 0.05) and the normal hearing specimens ( p < 0.05). BDNF-IR expression was similar in the unimplanted cochlea and in the normal cochlea. BDNF protein expression was increased despite complete loss of the organ of Corti hair cells and supporting cells. Even in the cases of CI with a 6-mm first-generation electrode, BDNF expression was upregulated throughout the cochlea. CONCLUSIONS: BDNF expression in the SGN appears to be upregulated by the electrical stimulation from CI. This study provides evidence that the electrical stimulation from CI may stimulate the expression of BDNF, playing a neuroprotective role in the rehabilitation of hearing in the deafened ear

Differential Expression of Na/K-ATPase in the Human Saccule of Patients With and Without Otologic Disease.

HYPOTHESIS: Na + , K + -ATPase (Na/K-ATPase) α1 subunit expression in the saccule of patients diagnosed with otologic disease is different compared with normal controls. BACKGROUND: We have recently characterized changes in the expression of Na/K-ATPase α1 subunit in the normal and pathological cochlea; however, no studies have determined the distribution Na/K-ATPase α1 subunit in the human saccule. The present study uses archival temporal bones to study the expression Na/K-ATPase α1 subunit in the human saccule. METHODS: Archival celloidin formalin fixed 20-micron thick sections of the vestibule from patients diagnosed with Menières disease (n = 5), otosclerosis (n = 5), sensorineural hearing loss, and normal hearing and balance (n = 5) were analyzed. Sections containing the saccular macula were immunoreacted with mouse monoclonal antibodies against Na/K-ATPase α1 subunit. Micrographs were acquired using a high-resolution digital camera coupled to a light inverted microscope. RESULTS: In the normal human saccule vestibular sensory epithelium, Na/K-ATPase α1 immunoreactivity (IR) was present in nerve fibers and calyces that surround type I vestibular hair cells and nerve terminals. The transition epithelium cells were also Na/K-ATPase α1 immunoreactive. Comparison between normal and pathological specimens showed that there was a significant reduction of Na/K-ATPase α1 IR in the saccule vestibular sensory epithelium from patients with Menières disease, otosclerosis, and sensorineural hearing loss. CONCLUSIONS: The decrease of Na/K-ATPase-IR α1 in the saccule vestibular sensory epithelium from patients with otopathologies suggests its critical role in inner ear homeostasis and pathology

Dynamic Molecular Markers of Otosclerosis in the Human Cochlea.

OBJECTIVE: To investigate the role and distribution of various molecular markers using immunohistochemistry and immunofluorescence to further elucidate and understand the pathogenesis of otosclerosis. METHODS: Archival celloidin formalin-fixed 20-micron thick histologic sections from 7 patients diagnosed with otosclerosis were studied and compared to controls. Sections in the mid-modiolar region were immunoreacted with rabbit polyclonal antibodies against nidogen-1, β2-laminin, collagen-IX, BSP, and monoclonal antibodies against TGF β-1 and ubiquitin. Digital images were acquired using a high-resolution light and laser confocal microscope. RESULTS: Nidogen-1, BSP, and collagen-IX were expressed in the otospongiotic regions, and to lesser extent, in the otosclerotic regions, the latter previously believed to be inactive. β2-laminin and ubiquitin were uniformly expressed in both otospongiotic and otosclerotic regions. There was a basal level of expression of all of these markers in the normal hearing and sensorineural hearing loss specimens utilized as control. TGF β -1, however, though present in the otosclerosis bones, was absent in the normal hearing and sensorineural hearing loss controls. CONCLUSIONS: Our results propose that the activity and function of TGF-1 may play a key role in the development and pathogenesis of otosclerosis. Further studies utilizing a higher number of temporal bone specimens will be helpful for future analysis and to help decipher its role as a potential target in therapeutic interventions

Oxidative Stress in the Blood Labyrinthine Barrier in the Macula Utricle of Meniere’s Disease Patients

The blood labyrinthine barrier (BLB) is critical in the maintenance of inner ear ionic and fluid homeostasis. Recent studies using imaging and histopathology demonstrate loss of integrity of the BLB in the affected inner ear of Meniere’s disease (MD) patients. We hypothesized that oxidative stress is involved in the pathogenesis of BLB degeneration, and to date there are no studies of oxidative stress proteins in the human BLB. We investigated the ultrastructural and immunohistochemical changes of the BLB in the vestibular endorgan, the macula utricle, from patients with MD (n = 10), acoustic neuroma (AN) (n = 6) and normative autopsy specimens (n = 3) with no inner ear disease. Each subject had a well-documented clinical history and audiovestibular testing. Utricular maculae were studied using light and transmission electron microscopy and double labeling immunofluorescence. Vascular endothelial cells (VECs) were identified using isolectin B4 (IB4) and glucose-transporter-1 (GLUT-1). Pericytes were identified using alpha smooth muscle actin (αSMA) and phalloidin. IB4 staining of VECS was consistently seen in both AN and normative. In contrast, IB4 was nearly undetectable in all MD specimens, consistent with the significant VEC damage confirmed on transmission electron microscopy. GLUT-1 was present in MD, AN, and normative. αSMA and phalloidin were expressed consistently in the BLB pericytes in normative, AN specimen, and Meniere’s specimens. Endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), and nitrotyrosine were used as markers of oxidative stress. The VECs of the BLB in Meniere’s had significantly higher levels of expression of iNOS and nitrotyrosine compared with normative and AN specimen. eNOS-IF staining showed similar patterns in normative and Meniere’s specimens. Microarray-based gene expression profiling confirmed upregulation of iNOS mRNA from the macula utricle of Meniere’s patients compared with AN. Nitrotyrosine, a marker recognized as a hallmark of inflammation, especially when seen in association with an upregulation of iNOS, was detected in the epithelial and stromal cells in addition to VECs in MD. Immunohistochemical and ultrastructural degenerative changes of the VEC suggest that these cells are the primary targets of oxidative stress, and pericyte pathology including degeneration and migration, likely also plays a role in the loss of integrity of the BLB and triggering of inflammatory pathways in MD. These studies advance our scientific understanding of oxidative stress in the human inner ear BLB and otopathology

Cochlear Ossification After Vestibular Schwannoma Surgery: A Temporal Bone Study.

OBJECTIVE: This study aims to investigate patterns of cochlear ossification (CO) in cadaveric temporal bones of patients who underwent vestibular schwannoma (VS) surgery via the translabyrinthine (TL), middle cranial fossa (MF), or retrosigmoid (RS) approaches. STUDY DESIGN: Histopathologic analysis of cadaveric temporal bones. SETTING: Multi-institutional national temporal bone repository. METHODS: The National Institute of Deafness and Communication Disorders and House Temporal Bone Laboratory at the University of California, Los Angeles and the Massachusetts Eye and Ear Otopathology Laboratory were searched for cadaveric temporal bones with a history of VS for which microsurgery was performed. Exclusion criteria included non-VS and perioperative death within 30 days of surgery. Temporal bones were analyzed histologically for CO of the basal, middle, and apical turns. RESULTS: Of 92 temporal bones with a history of schwannoma from both databases, 12 of these cases met the inclusion criteria. The approaches for tumor excision included 2 MF, 4 RS, and 6 TL approaches. CO was observed in all temporal bones that had undergone TL surgery. Among temporal bones that had undergone MF or RS surgeries, 5/6 had no CO, and 1/6 had partial ossification. This single case was noted to have intraoperative vestibular violation after RS surgery upon histopathologic and chart review. CONCLUSION: In this temporal bone series, all temporal bones that had undergone TL demonstrated varying degrees of CO on histological analysis. MF and RS cases did not exhibit CO except in the case of vestibular violation. When cochlear implantation is planned or possible after VS surgery, surgeons may consider using a surgical approach that does not violate the labyrinth

Innovative Treatment of a Fetal Lung Mass Model Using High-intensity Focused Ultrasound (HIFU)

Current therapy for space-occupying fetal lung mass lesions (fetal pulmonary lobectomy) is invasive and technically demanding. Accordingly, new therapeutic procedures are required which are much less invasive and more efficient. The purpose of this study was to investigate the feasibility of high-intensity focused ultrasound (HIFU) as a new therapeutic modality for fetal lung mass lesions, using an experimental animal model. We created a solid fetal lung model by differential lung ventilation using anesthetized adult rabbits. In this model, experimental animals with a unilateral independent (fluid-filled) lung were maintained by single lung ventilation of the other dependent lung. Within the independent lung, target blood vessels depicted by color flow Doppler were repeatedly irradiated with HIFU energy beams (n=19). Occlusion of these blood vessels in vivo was confirmed by evaluation of the flow using color flow Doppler. After the procedure, the animals were sacrificed and their harvested lungs were assessed grossly and microscopically. Pulmonary blood vessels (artery and/or vein) were effectively occluded with 2 to 5 cycles of HIFU energy delivery (10.5 seconds each) with a success rate of 62.5% (arteries) and 72.7% (veins). No clear changes including tissue perforations were observed grossly on the surface of the lungs. Ultrasound-guided HIFU energy delivery seems promising for occlusion of the pulmonary blood vessels within a fluid-filled independent lung (fetal lung model). Thus in the future, HIFU irradiation could be used as a less invasive technique to occlude the feeding vessels of fetal lung mass lesions in utero

Discovery of widespread transcription initiation at microsatellites predictable by sequence-based deep neural network

Using the Cap Analysis of Gene Expression (CAGE) technology, the FANTOM5 consortium provided one of the most comprehensive maps of transcription start sites (TSSs) in several species. Strikingly, ~72% of them could not be assigned to a specific gene and initiate at unconventional regions, outside promoters or enhancers. Here, we probe these unassigned TSSs and show that, in all species studied, a significant fraction of CAGE peaks initiate at microsatellites, also called short tandem repeats (STRs). To confirm this transcription, we develop Cap Trap RNA-seq, a technology which combines cap trapping and long read MinION sequencing. We train sequence-based deep learning models able to predict CAGE signal at STRs with high accuracy. These models unveil the importance of STR surrounding sequences not only to distinguish STR classes, but also to predict the level of transcription initiation. Importantly, genetic variants linked to human diseases are preferentially found at STRs with high transcription initiation level, supporting the biological and clinical relevance of transcription initiation at STRs. Together, our results extend the repertoire of non-coding transcription associated with DNA tandem repeats and complexify STR polymorphism