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BioRxiv : the Preprint Server For... Jun 2024Age-related hearing impairment is the most common cause of hearing loss and is one of the most prevalent conditions affecting the elderly globally. It is influenced by a...
Age-related hearing impairment is the most common cause of hearing loss and is one of the most prevalent conditions affecting the elderly globally. It is influenced by a combination of environmental and genetic factors. The mouse and human inner ears are functionally and genetically homologous. Investigating the genetic basis of age-related hearing loss (ARHL) in an outbred mouse model may lead to a better understanding of the molecular mechanisms of this condition. We used Carworth Farms White (CFW) outbred mice, because they are genetically diverse and exhibit variation in the onset and severity of ARHL. The goal of this study was to identify genetic loci involved in regulating ARHL. Hearing at a range of frequencies was measured using Auditory Brainstem Response (ABR) thresholds in 946 male and female CFW mice at the age of 1, 6, and 10 months. We obtained genotypes at 4.18 million single nucleotide polymorphisms (SNP) using low-coverage (mean coverage 0.27x) whole-genome sequencing followed by imputation using STITCH. To determine the accuracy of the genotypes we sequenced 8 samples at >30x coverage and used calls from those samples to estimate the discordance rate, which was 0.45%. We performed genetic analysis for the ABR thresholds for each frequency at each age, and for the time of onset of deafness for each frequency. The SNP heritability ranged from 0 to 42% for different traits. Genome-wide association analysis identified several regions associated with ARHL that contained potential candidate genes, including , , , , and . We confirmed, using functional study, that Prkag2 deficiency causes age-related hearing loss at high frequency in mice; this makes a candidate gene for further studies. This work helps to identify genetic risk factors for ARHL and to define novel therapeutic targets for the treatment and prevention of ARHL.
PubMed: 38915500
DOI: 10.1101/2024.06.10.598304 -
NMC Case Report Journal 2024Superficial siderosis (SS) of the central nervous system is a rare disorder that is caused by chronic or recurrent hemorrhage in the subarachnoid space via a dural...
Superficial siderosis (SS) of the central nervous system is a rare disorder that is caused by chronic or recurrent hemorrhage in the subarachnoid space via a dural defect at the spinal level. The most common clinical features of SS include slow-progressive sensorineural deafness, cerebellar symptoms, and pyramidal tract signs. Considering that SS can present with broad clinical manifestations, for precise diagnosis, this disease must be understood. Anti-Ro/SSA antibodies are commonly detected in patients with Sjögren's syndrome and are utilized as markers for autoimmune diseases. In this report, we present a unique pathological condition in which SS coincided with a positive anti-Ro/SSA antibody test result. During the diagnosis of gait disturbance, an elevation in anti-Ro/SSA antibody was detected, and steroid pulse therapy was initiated as the initial treatment for autoimmune diseases. Head magnetic resonance imaging (MRI) revealed extensive hypointensity as a dark band that surrounded the intracranial basal structures and cerebellar hemispheres. Spinal MRI indicated ventral longitudinal intraspinal fluid collection extending from C7 to T5 as well as a defect in the ventral T2-3 dura mater. Intraoperative visualization revealed that the intradural venous plexus was the source of bleeding that caused the SS. To our knowledge, this report is the first to discuss the presence of anti-Ro/SSA antibodies in patients with SS. The role of anti-Ro/SSA antibodies in the pathophysiology of SS remains unclear; therefore, to confirm a possible association, further research and accumulation of cases are required.
PubMed: 38911924
DOI: 10.2176/jns-nmc.2023-0214 -
Alzheimer's & Dementia (New York, N. Y.) 2024Alzheimer's disease and related dementias (ADRDs) and age-related hearing loss are the intersection of two major public health challenges. With age as the primary risk...
Alzheimer's disease and related dementias (ADRDs) and age-related hearing loss are the intersection of two major public health challenges. With age as the primary risk factor for both disease processes, the burden of ADRDs and age-related hearing loss is growing, and each field maintains significant barriers to broadscale identification and management that is affordable and accessible. With the disproportionate burden of ADRDs among racial and ethnic minority older adults and existing disparities within hearing care, both areas face challenges in achieving equitable access and outcomes across diverse populations. The publication of the Aging and Cognitive Health Evaluation in Elders (ACHIEVE) trial in July 2023 marked a significant moment in the fields of brain and hearing health. The ACHIEVE trial was the first randomized controlled trial to examine whether providing hearing intervention, specifically provision of hearing aids, compared to an education control, would reduce cognitive changes over 3 years. The participants most at risk for cognitive decline, with lower education, lower income, more likely to identify as Black, and have more cardiovascular risk factors, were the participants who benefited most from the hearing intervention and are also the least likely to be represented in research and the least likely to obtain hearing care. With growing evidence of the interconnection between cognitive and sensory health, we have an opportunity to prioritize equity, from purposeful inclusion of diverse participants in trials to influencing the emerging market of over-the-counter hearing aids to supporting expanded models of hearing care that reach those who have traditionally gone unserved. No longer can hearing go unrecognized by clinicians, researchers, and advocates for brain health. At the same time, the fields of brain and hearing health must center equity if we are going to meet the needs of diverse older adults in a world in which hearing health matters.
PubMed: 38911874
DOI: 10.1002/trc2.12484 -
European Journal of Medical Genetics Jun 2024This paper reports the discovery of a m.C1494T pedigree in the east of England made during a search for matrilineal relations of King Richard III. The mitochondrial DNA...
This paper reports the discovery of a m.C1494T pedigree in the east of England made during a search for matrilineal relations of King Richard III. The mitochondrial DNA variant m.C1494T has been associated with aminoglycoside-induced deafness. This variant is very uncommon. although pedigrees with this variant have previously been found in China and Spain. The members of the newly identified pedigree all belong to the mitochondrial haplogroup J1c2c3, which is also the haplogroup of King Richard III. The presence of a few people in the USA from the same haplogroup has previously been noted, and it is now known that one of the people can show his descent from a couple who lived in Nottinghamshire, England, in the late 1700's. The mitochondrial DNA sequence of this man, at present living in the USA, and of his 4th cousin, twice removed, living in Lincoln, England, has shown they belong to haplogroup J1c2c3 and both have the variant m.C1494T; thereby, allowing the production of a multi-generational pedigree originating in the east of England. Fortunately, deafness has not been found in any living member of this large pedigree. It was also noted that the link to the family of King Richard III has not been firmly defined; however the circumstantial evidence is strong as many of his family members lived in this part of England.
PubMed: 38897372
DOI: 10.1016/j.ejmg.2024.104957 -
Hearing Research Jun 2024Hearing impairment is the most prevalent sensory disease in humans and can have dramatic effects on the development, and preservation, of our cognitive abilities and... (Review)
Review
Hearing impairment is the most prevalent sensory disease in humans and can have dramatic effects on the development, and preservation, of our cognitive abilities and social interactions. Currently 20 % of the world's population suffer from a form of hearing impairment; this is predicted to rise to 25 % by 2050. Despite this staggering disease load, and the vast damage it inflicts on the social, medical and economic fabric of humankind, our ability to predict, or prevent, the loss of hearing is very poor indeed. We here make the case for a paradigm shift in our approach to studying deafness. By exploiting more forcefully the molecular-genetic conservation between human hearing and hearing in morphologically distinct models, such as the fruit fly Drosophila melanogaster, we believe, a deeper understanding of hearing and deafness can be achieved. An understanding that moves beyond the surface of the 'deafness genes' to probe the underlying bedrock of hearing, which is shared across taxa, and partly shared across modalities. When it comes to understanding the workings (and failings) of human sensory function, a simple fruit fly has a lot to offer and a fly eye might sometimes be a powerful model for a human ear. Particularly the use of fly avatars, in which specific molecular (genetic or proteomic) states of humans (e.g. specific patients) are experimentally reproduced, in order to study the corresponding molecular mechanisms (e.g. specific diseases) in a controlled yet naturalistic environment, is a tool that promises multiple unprecedented insights. The use of the fly - and fly avatars - would benefit humans and will help enhance the power of other scientific models, such as the mouse.
PubMed: 38896942
DOI: 10.1016/j.heares.2024.109047 -
Historia, Ciencias, Saude--Manguinhos 2024This text presents the partial results of ongoing research into deafness in history teaching and historiography between 2015 and 2022. The study problematizes the place...
This text presents the partial results of ongoing research into deafness in history teaching and historiography between 2015 and 2022. The study problematizes the place of disabled people in top-ranking periodicals (the top two categories in Brazil) and in pedagogical projects on degree courses in history (with and without teacher-training certification) at the University of São Paulo and the State University of Campinas. These universities were chosen because they topped the ranking in a survey conducted by Folha de S.Paulo newspaper. The study observes how the Brazilian Inclusion Law (law 13.146, of July 6, 2015) is incorporated into the initial training of these professionals.
Topics: Humans; Brazil; Historiography; Deafness; Universities; History, 21st Century; Disabled Persons
PubMed: 38896751
DOI: 10.1590/S0104-59702024000100028 -
Ear, Nose, & Throat Journal Jun 2024To analyze the etiology, diagnosis, and treatment of unexplained conductive hearing loss (UCHL) with intact tympanic membrane. A systematic review was conducted based... (Review)
Review
To analyze the etiology, diagnosis, and treatment of unexplained conductive hearing loss (UCHL) with intact tympanic membrane. A systematic review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 642 articles were retrieved from databases such as PubMed, Embase, Web of Science, and Cochrane. Fifty-four research articles and 21 case reports were screened out according to the inclusion and exclusion criteria for analysis of the etiology of UCHL. Seven research articles with UCHL who underwent exploratory tympanotomy were selected for data extraction and analysis of clinical characteristics. UCHL is a common manifestation of various diseases, including congenital ossicular anomalies (COA), otosclerosis (OTS), congenital middle ear cholesteatoma (CMEC), oval window atresia, superior semicircular-canal dehiscence, congenital stapedial footplate fixation, middle ear osteoma or adenoma, congenital ossification of stapedial tendon, and so on. A total of 522 patients were included in the 7 articles; among whom OTS showed a tendency to increase with age. The main symptoms were hearing loss, followed by tinnitus, dizziness, ear fullness, ear pain, facial paralysis. A total of 87.5% to 93.0% patients with COA manifested as nonprogressive deafness that occurred since childhood, with tinnitus incidence of 15.6% to 30.2%, and 86.4% to 96.4% patients with OTS presented with progressive hearing loss, with tinnitus incidence of 60.1% to 90.9%. The diagnosis positive rate of high-resolution computed tomography (HRCT) was 33.8% to 87.1%, and CMEC was higher than that of COA (83.3%-100% vs 28.6%-64%). All the articles reported good hearing recovery. The most common surgical complications included taste abnormalities, tinnitus, and dizziness. UCHL presents with similar clinical manifestations and poses challenges in preoperative diagnosis. Exploratory tympanotomy is the primary method for diagnosis and treatment, with good prognosis after removing the lesion and reconstructing hearing during the operation. Children can also safely undergo the surgery.
PubMed: 38895947
DOI: 10.1177/01455613241262129 -
BioRxiv : the Preprint Server For... Jun 2024Noise can induce hearing loss. In particularly, noise can induce cochlear synapse degeneration leading to hidden hearing loss, which is the most common type of hearing...
UNLABELLED
Noise can induce hearing loss. In particularly, noise can induce cochlear synapse degeneration leading to hidden hearing loss, which is the most common type of hearing disorders in the clinic. Currently, there is no pharmacological treatment, particularly, no post-exposure (i.e., therapeutic) treatment available in the clinic. Here, we report that systematic administration of K channel blockers before or after noise exposure could significantly attenuate NIHL and synapse degeneration. After systematic administration of a general K-channel blocker tetraethylammonium (TEA), the elevation of auditory brainstem response (ABR) thresholds after noise-exposure significantly reduced, and the active cochlear mechanics significantly improved. The therapeutic effect was further improved as the post-exposure administration time extending to 3 days. BK channel is a predominant K channel in the inner hair cells. Systematic administration of a BK channel blocker GAL-021 after noise exposure also ameliorated hearing loss and improved hearing behavioral responses tested by acoustic startle response (ASR). Finally, both TEA and GAL-021 significantly attenuated noise-induced ribbon synapse degeneration. These data demonstrate that K -channel blockers can prevent and treat NIHL and cochlear synapse degeneration. Our finding may aid in developing therapeutic strategies for post-exposure treatment of NIHL and synapse degeneration.
SIGNIFICANCE STATEMENT
Noise is a common deafness factor affecting more 100 million people in the United States. So far, there is no pharmacological treatment available. We show here that administration of K channel blockers after noise exposure could attenuate noise-induced hearing loss and synapse degeneration, and improved behavioral responses. This is the first time to real the K channel blockers that could treat noise-induced hearing loss and cochlear synaptopathy after noise exposure.
PubMed: 38895254
DOI: 10.1101/2024.06.04.597382 -
Iranian Journal of Public Health Feb 2024Hearing loss is the second most common disease after mental retardation in Iran. Autosomal recessive non-syndromic hearing loss (ARNSHL) is an extreme and highly...
BACKGROUND
Hearing loss is the second most common disease after mental retardation in Iran. Autosomal recessive non-syndromic hearing loss (ARNSHL) is an extreme and highly heterogeneous disease, for which more than 70 genes have been identified. Considering the frequency of family marriage as well as the importance of ARNSHL in Iran, we evaluated the genetic factors involved in this type of deafness.
METHODS
We performed the whole exome sequencing (WES) of eight Iranian subjects with severe nonsyndromic hearing loss selected from 110 well-characterized subjects with non-syndromic hearing loss from 2017-2019. The patients with mutated and genes were excluded from the study.
RESULTS
The use of the whole exome sequencing method revealed 10 different mutations in 7 genes, including c.1234G>T), (c.45DelC, c.466T>C), (c.12528-2A>C, c.16226-16227insAGTC), (c.7454delG), (c.3570+2T>C), (c.992G>A), (c.2359G>T, c.2353A>C). Seven new variants were observed in seven families including (c.1234G>T), (c.45DelC), (c.12528-2A>C), (c.7454delG), (c.16226-16227insAGTC), (c.3570+2T>C).
CONCLUSION
The causal mutation of ARNSHL was found in all patients using the WES. Meta-analysis studies can help to identify common mutations causing deafness in any population to facilitate identification of carriers and subjects with deafness.
PubMed: 38894825
DOI: 10.18502/ijph.v53i2.14930 -
Cancers May 2024NF2-related Schwannomatosis (NF2-SWN) is a disease that needs new solutions. The hallmark of NF2-SWN, a dominantly inherited neoplasia syndrome, is bilateral vestibular...
NF2-related Schwannomatosis (NF2-SWN) is a disease that needs new solutions. The hallmark of NF2-SWN, a dominantly inherited neoplasia syndrome, is bilateral vestibular schwannomas (VSs), which progressively enlarge, leading to sensorineural hearing loss, tinnitus, facial weakness, and pain that translates to social impairment and clinical depression. Standard treatments for growing VSs include surgery and radiation therapy (RT); however, both carry the risk of further nerve damage that can result in deafness and facial palsy. The resultant suffering and debility, in combination with the paucity of therapeutic options, make the effective treatment of NF2-SWN a major unmet medical need. A better understanding of these mechanisms is essential to developing novel therapeutic targets to control tumor growth and improve patients' quality of life. Previously, we developed the first orthotopic cerebellopontine angle mouse model of VSs, which faithfully mimics tumor-induced hearing loss. In this model, we observed that mice exhibit symptoms of ataxia and vestibular dysfunction. Therefore, we further developed a panel of five tests suitable for the mouse VS model and investigated how tumor growth and treatment affect gait, coordination, and motor function. Using this panel of ataxia tests, we demonstrated that both ataxia and motor function deteriorated concomitantly with tumor progression. We further demonstrated that (i) treatment with anti-VEGF resulted in tumor size reduction, mitigated ataxia, and improved rotarod performance; (ii) treatment with crizotinib stabilized tumor growth and led to improvements in both ataxia and rotarod performance; and (iii) treatment with losartan did not impact tumor growth nor ameliorate ataxia or motor function. Our studies demonstrated that these methods, paired with hearing tests, enable a comprehensive evaluation of tumor-induced neurological deficits and facilitate the assessment of the effectiveness of novel therapeutics to improve NF2 treatments.
PubMed: 38893082
DOI: 10.3390/cancers16111961