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1.
Artigo em Inglês | MEDLINE | ID: mdl-38831582

RESUMO

Objectives: To explore the functional consequences of two common variants, p.V37I and c.299-300delAT in hearing loss associated gene GJB2. Methods: Connexin 26 expression and gap junctional permeability were studied in HEK 293T cells transfected with plasmids expressing GJB2 wild-type, p.V37I, or c.299-300delAT CX26 proteins with fluorescent tags. Functional analyses of different GJB2 haplotypes were performed to fully assess the alteration of ionic and small-molecule coupling. Results: The p.V37I protein was localized at the plasma membrane, but failed to effectively transport intercellular propidium iodide or Ca2+ efficiently, indicating impairment of both biochemical and ionic coupling. The presence of GJB2 p.V37I appeared to increase the sensitivity of cells to H2O2 treatment. In contrast, the known variant c.299-300delAT protein was not transported to the cell membrane and could not form gap junctions, instead being confined to the cytoplasm. Ionic and biochemical coupling was defective in c.299-300delAT-transfected cells. Conclusion: The p.V37I and c.299-300delAT GJB2 mutations resulted in deficient gap junction-mediated coupling. Environmental factors may impact the functional consequences of GJB2 p.V37I. These results may inspire the development of molecular therapies targeting GJB2 mutations for hearing loss.

2.
Hear Res ; 447: 109012, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703433

RESUMO

Hearing loss is a common side effect of many tumor treatments. However, hearing loss can also occur as a direct result of certain tumors of the nervous system, the most common of which are the vestibular schwannomas (VS). These tumors arise from Schwann cells of the vestibulocochlear nerve and their main cause is the loss of function of NF2, with 95 % of cases being sporadic and 5 % being part of the rare neurofibromatosis type 2 (NF2)-related Schwannomatosis. Genetic variations in NF2 do not fully explain the clinical heterogeneity of VS, and interactions between Schwann cells and their microenvironment appear to be critical for tumor development. Preclinical in vitro and in vivo models of VS are needed to develop prognostic biomarkers and targeted therapies. In addition to VS, other tumors can affect hearing. Meningiomas and other masses in the cerebellopontine angle can compress the vestibulocochlear nerve due to their anatomic proximity. Gliomas can disrupt several neurological functions, including hearing; in fact, glioblastoma multiforme, the most aggressive subtype, may exhibit early symptoms of auditory alterations. Besides, treatments for high-grade tumors, including chemotherapy or radiotherapy, as well as incomplete resections, can induce long-term auditory dysfunction. Because hearing loss can have an irreversible and dramatic impact on quality of life, it should be considered in the clinical management plan of patients with tumors, and monitored throughout the course of the disease.


Assuntos
Perda Auditiva , Audição , Neuroma Acústico , Humanos , Neuroma Acústico/patologia , Neuroma Acústico/fisiopatologia , Neuroma Acústico/complicações , Perda Auditiva/fisiopatologia , Perda Auditiva/etiologia , Perda Auditiva/patologia , Animais , Neurilemoma/patologia , Neurilemoma/complicações , Neurilemoma/terapia , Nervo Vestibulococlear/patologia , Nervo Vestibulococlear/fisiopatologia , Fatores de Risco , Neurofibromatose 2/genética , Neurofibromatose 2/complicações , Neurofibromatose 2/patologia , Neurofibromatose 2/fisiopatologia , Neurofibromatose 2/terapia , Meningioma/patologia , Meningioma/fisiopatologia , Meningioma/complicações
3.
Yonago Acta Med ; 67(2): 93-99, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38803594

RESUMO

Alström syndrome is a form of inherited obesity caused by a single gene abnormality and is inherited as an autosomal recessive trait. It is characterised by a variety of clinical manifestations, including progressive visual and hearing impairment, type 2 diabetes mellitus, dilated cardiomyopathy, and hepatic and renal dysfunction, in addition to obesity. Recent insights underline the pivotal involvement of the disease-associated gene (ALMS1) in cilia formation and function, leading to the classification of its clinical manifestations as a ciliopathy. This review delineates the diverse clinical indicators defining the syndrome and elucidates its pathological underpinnings.

4.
Mol Syndromol ; 13(4): 305-317, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36158049

RESUMO

Variation in the mitochondrial tRNA Lys gene at position 8296 was previously found to be associated with maternally inherited diabetes mellitus and deafness, hypertrophic cardiomyopathy, myoclonic epilepsy with ragged-red fibers and mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes. The pathogenicity of the m.8296A>G variation is unclear. In this study, we aimed to analyze the mitochondrial proteome in a patient with m.8296A>G variation to elucidate the effects of this mutation at the protein level. Whole-exome sequencing and mitochondrial genome analysis were performed in a patient with sensorineural hearing impairment, cognitive impairment, leukodystrophy, migraine-like headaches, and gastrointestinal dysmotility. Mitochondrial genome analysis identified a homoplasmic m.8296A>G variation in the mitochondrial tRNA Lys gene in the proband and unaffected mother. Global mitochondrial proteome analysis was carried out in the muscle mitochondria of the index patient and a control subject. Comparative muscle mitochondrial proteome analysis revealed a total of 13 nuclear-encoded mitochondrial proteins differently expressed with respect to the control. Ten of the 13 proteins were downregulated. Most of the proteins were involved in ATP synthesis and Krebs cycle and have strong interactions with each other. We considered the m.8296A>G variation to be pathogenic with variable penetrance for our patient's phenotype, and this variation led to different expressions of nuclear-encoded proteins involved in energy metabolism.

5.
Biomedicines ; 10(8)2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-36009393

RESUMO

Cochlear implantation is the treatment of choice for children with profound sensorineural hearing impairment (SNHI), yet the outcomes of cochlear implants (CI) vary significantly across individuals. To investigate the CI outcomes in pediatric patients with SNHI due to various etiologies, we prospectively recruited children who underwent CI surgery at two tertiary referral CI centers from 2010 to 2021. All patients underwent comprehensive history taking, next generation sequencing (NGS)-based genetic examinations, and imaging studies. The CI outcomes were evaluated using Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores. Of the 160 pediatric cochlear implantees (76 females and 84 males) included in this study, comprehensive etiological work-up helped achieve clinical diagnoses in 83.1% (133/160) of the patients, with genetic factors being the leading cause (61.3%). Imaging studies identified certain findings in 31 additional patients (19.3%). Four patients (2.5%) were identified with congenital cytomegalovirus infection (cCMV), and 27 patients (16.9%) remained with unknown etiologies. Pathogenic variants in the four predominant non-syndromic SNHI genes (i.e., SLC26A4, GJB2, MYO15A, and OTOF) were associated with favorable CI outcomes (Chi-square test, p = 0.023), whereas cochlear nerve deficiency (CND) on imaging studies was associated with unfavorable CI outcomes (Chi-square test, p < 0.001). Our results demonstrated a clear correlation between the etiologies and CI outcomes, underscoring the importance of thorough etiological work-up preoperatively in pediatric CI candidates.

6.
Medicina (Kaunas) ; 58(2)2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35208557

RESUMO

BACKGROUND: The incidence of hearing loss is constantly increasing and according to the World Health Organization, by 2050, 900 million people will suffer from hearing loss. The main Objective of the study was to determine the differences between the severity of the symptoms of stress, anxiety and depression in participants with varying degrees of sensorineural hearing loss during the COVID-19 pandemic. An additional aim was to examine the extent and manner in which protective face masks impact the communication of people with hearing loss. Matrials and Methods: A cross-sectional study was conducted, which included 160 patients (81 men and 79 women) with bilateral sensorineural hearing loss. The patients' age range was 50 to 80 years. Depending on the degree of hearing loss or pure-tone threshold, the participants were divided into four groups: mild hearing loss, moderate hearing loss, severe hearing loss and profound hearing loss. The research used the Depression, Anxiety and Stress Scale (DASS-21) and a questionnaire in which the participants reported whether surgical face masks (medical three-layer masks) worn by speakers makes communication difficult, to what extent and in what way. RESULTS: The average age of the patients was 67.97 ± 8.16. A significant correlation was found between the degree of hearing loss and communication difficulties caused by the use of protective face masks (p < 0.001). For patients with severe and profound hearing loss, communication is significantly more difficult (50.0% and 45.0% respectively) when the interlocutor wears a face mask. There is a significant correlation between the degree of hearing loss and the way in which communication is made more difficult when the interlocutor wears a face mask (p < 0.001). A statistically significant difference was determined between the degrees of hearing loss in all measured subscales: stress (p = 0.024), anxiety (p = 0.026) and depression (p = 0.016). CONCLUSIONS: We have determined that face masks used during the COVID-19 pandemic significantly hamper communication among the study groups (p = 0.007) and there is a significant correlation between the degree of sensorineural hearing loss and the presence of symptoms in all three DASS-21 subscales, meaning that the symptoms of stress, anxiety and depression were more intense in severe and profound hearing loss.


Assuntos
COVID-19 , Perda Auditiva Neurossensorial , Idoso , Idoso de 80 Anos ou mais , Ansiedade/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Feminino , Perda Auditiva Neurossensorial/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2
7.
Artigo em Inglês | MEDLINE | ID: mdl-34667072

RESUMO

There is increasing recognition for the contribution of genetic mosaicism to human disease, particularly as high-throughput sequencing has enabled detection of sequence variants at very low allele frequencies. Here, we describe an infant male who presented at 9 mo of age with hypotonia, dysmorphic features, congenital heart disease, hyperinsulinemic hypoglycemia, hypothyroidism, and bilateral sensorineural hearing loss. Whole-genome sequencing of the proband and the parents uncovered an apparent de novo mutation in the X-linked SMS gene. SMS encodes spermine synthase, which catalyzes the production of spermine from spermidine. Inactivation of the SMS gene disrupts the spermidine/spermine ratio, resulting in Snyder-Robinson syndrome. The variant in our patient is absent from the gnomAD and ExAC databases and causes a missense change (p.Arg130Cys) predicted to be damaging by most in silico tools. Although Sanger sequencing confirmed the de novo status in our proband, polymerase chain reaction (PCR) and deep targeted resequencing to ∼84,000×-175,000× depth revealed that the variant is present in blood from the unaffected mother at ∼3% variant allele frequency. Our findings thus provided a long-sought diagnosis for the family while highlighting the role of parental mosaicism in severe genetic disorders.


Assuntos
Deficiência Intelectual Ligada ao Cromossomo X , Mosaicismo , Humanos , Lactente , Masculino , Mutação de Sentido Incorreto , Espermina Sintase/genética
8.
Eur Thyroid J ; 10(3): 215-221, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34178707

RESUMO

BACKGROUND: An association between hearing impairment (HI) and congenital hypothyroidism (CH) has been reported previously. However, in general, studies were retrospective and had small sample sizes, and the results were variable and inconclusive. The aim of our study was to assess the prevalence of HI among patients with CH and to examine factors potentially predictive of HI including severity of CH, etiology of CH, and timing of treatment initiation. METHODS: Audiometry was undertaken prospectively in 66 patients aged 3-21 years diagnosed with primary CH and 49 healthy matched controls. All patients with HI underwent examination by an otolaryngologist, and in patients with sensorineural loss, brainstem evoked response audiometry was performed. A next-generation sequencing (NGS) panel for genes involved in deafness was performed in patients with sensorineural HI to exclude additional genetic etiologies. RESULTS: HI was found in 19 patients (28.7%). Among them, 5 (7.6%) had moderate to severe bilateral sensorineural impairment and 14 (21.2%) had mild conductive HI. Conductive HI was bilateral in 5 of these patients (36%). None of the controls had HI. No specific etiology was found in patients with HI, and no differences were identified in age at diagnosis, age at initiation of levothyroxine (LT4) therapy, gender, or ethnicity between patients with and without HI. A nonsignificant trend toward lower mean screening TT4 levels was found in patients with HI (compared to those without HI) (3.42 vs. 5.34 µg/dL, p = 0.095). No pathogenic variants in genes attributed to HI were identified by NGS in the 5 patients with sensorineural deafness, indicating that HI in these patients was likely attributable to CH rather than other genetic etiologies. CONCLUSIONS: Our findings indicate a high prevalence of HI among patients with CH, predominantly of the conductive type. HI was not associated with the etiology of CH or with delayed initiation of LT4 therapy. Audiometry is recommended for children diagnosed with CH and repeat monitoring may be warranted to identify acquired HI and to prevent long-term sequelae of undiagnosed deafness.

9.
Artigo em Inglês | MEDLINE | ID: mdl-34021019

RESUMO

Hearing loss (HL) is the most common congenital sensory impairment. Usher syndrome (USH) is the leading genetic etiology of congenital deafness combined with progressive vision loss, and individuals presenting with these symptoms are often assumed to have USH. This can be an erroneous assumption, as there are additional genetic causes of deaf-blindness. Our objective is to describe and accurately diagnose non-USH genetic causes of deaf-blindness. We present three children with hearing and vision loss with clinical and genetic findings suggestive of USH. However, ongoing clinical assessment did not completely support an USH diagnosis, and exome analysis was pursued for all three individuals. Updated genetic testing showed pathogenic variants in ALMS1 in the first individual and TUBB4B in the second and third. Although HL in all three was consistent with USH type 2, vision impairment with retinal changes was noted by age 2 yr, which is unusual for USH. In all three the updated genotype more accurately fit the clinical phenotype. Because USH is the most common form of genetic deaf-blindness, individuals with HL, early vision impairment, and retinal dysfunction are often assumed to have USH. However, additional genes associated with HL and retinal impairment include ALMS1, TUBB4B, CEP78, ABHD12, and PRPS1 Accurate genetic diagnosis is critical to these individuals' understanding of their genetic conditions, prognosis, vision and hearing loss management, and future access to molecular therapies. If clinically or genetically USH seems uncertain, updated genetic testing for non-USH genes is essential.


Assuntos
Cegueira/genética , Perda Auditiva/genética , Síndromes de Usher/diagnóstico , Proteínas de Ciclo Celular/genética , Pré-Escolar , Diagnóstico Diferencial , Feminino , Testes Genéticos , Genótipo , Humanos , Masculino , Tubulina (Proteína)/genética , Sequenciamento do Exoma , Adulto Jovem
10.
Artigo em Inglês | MEDLINE | ID: mdl-32532883

RESUMO

We present a case of 9p- syndrome with a complex chromosomal event originally characterized by the classical karyotype approach as 46,XX,der(9)t(9;13)(p23;q13). We used advanced technologies (Bionano Genomics genome imaging and 10× Genomics sequencing) to characterize the location of the translocation and accompanying deletion on Chromosome 9 and duplication on Chromosome 13 with single-nucleotide breakpoint resolution. The translocation breakpoint was at Chr 9:190938 and Chr 13:50850492, the deletion at Chr 9:1-190938, and the duplication at Chr 13:50850492-114364328. We identified genes in the deletion and duplication regions that are known to be associated with this patient's phenotype (e.g., ZIC2 in dysmorphic facial features, FOXD4 in developmental delay, RNASEH2B in developmental delay, and PCDH9 in autism). Our results indicate that clinical genomic assessment of individuals with complex karyotypes can be refined to a single-base-pair resolution when utilizing Bionano and 10× Genomics sequencing. With the 10× Genomics data, we were also able to characterize other variation (e.g., loss of function) throughout the remainder of the patient's genome. Overall, the Bionano and 10× technologies complemented each other and provided important insight into our patient with 9p- syndrome. Altogether, these results indicate that newer technologies can identify precise genomic variants associated with unique patient phenotypes that permit discovery of novel genotype-phenotype correlations and therapeutic strategies.


Assuntos
Pontos de Quebra do Cromossomo , Genômica , Translocação Genética , Criança , Deleção Cromossômica , Duplicação Cromossômica , Mapeamento Cromossômico , Cromossomos Humanos Par 9/genética , Hibridização Genômica Comparativa , Feminino , Genômica/métodos , Humanos , Cariótipo , Mutação com Perda de Função , Fenótipo , Análise de Sequência de DNA
11.
Eur J Med Genet ; 63(3): 103733, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31449985

RESUMO

Biallelic variants in HARS2 have been associated with Perrault syndrome, characterized by sensorineural hearing impairment and premature ovarian insufficiency. Here we report three novel families, compound heterozygous for missense variants in HARS2 identified by next-generation sequencing, namely c.172A > G (p.Lys58Glu) and c.448C > T (p.Arg150Cys) identified in two sisters aged 13 and 16 years and their older brother, c.448C > T (p.Arg150Cys) and c.980G > A (p.Arg327Gln) identified in a seven year old girl, and finally c.137T > A (p.Leu46Gln) and c.259C > T (p.Arg87Cys) identified in a 32 year old woman. Clinically, all five individuals presented with early onset, rapidly progressive hearing impairment. Whereas the oldest female fulfilled the criteria of Perrault syndrome, the three younger females, aged 7, 13 and 16, all had apparently normal ovarian function, apart from irregular menstrual periods in the oldest female at age 16. The present report expands the list of HARS2 variants and helps gain further knowledge to the phenotype.


Assuntos
Aminoacil-tRNA Sintetases/genética , Disgenesia Gonadal 46 XX/genética , Perda Auditiva Neurossensorial/genética , Perda Auditiva/genética , Insuficiência Ovariana Primária/genética , Adolescente , Adulto , Criança , Feminino , Disgenesia Gonadal 46 XX/fisiopatologia , Perda Auditiva/fisiopatologia , Perda Auditiva Neurossensorial/fisiopatologia , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Mutação de Sentido Incorreto , Linhagem , Sequenciamento do Exoma
12.
Artigo em Inglês | MEDLINE | ID: mdl-31160358

RESUMO

Coffin-Siris syndrome (CSS) is a developmental disability, caused by genomic variants in the gene SMARCA4, in addition to other known genes, but the full spectrum of SMARCA4 variants that can cause CSS is unknown with 40% of cases not having molecular confirmation. In this report, we identify a patient with CSS, a severe cardiac phenotype, and a novel SMARCA4 variant. There is no experimental structure of human SMARCA4, so we use molecular modeling techniques to generate a structural model of human SMARCA4. We then map known SMARCA4 variants causative of CSS and our novel variant to the model. We use the resulting information to support the interpretation that the novel variant is causative of disease in our patient. Modeling demonstrates that the variant found in our patient is in a region of SMARCA4 associated with DNA binding, as are the other known pathogenic SMARCA4 variants mapped. Because of this structural information, we discuss how these variants may be disease-causing through a dominant negative effect of disrupting DNA binding.


Assuntos
Anormalidades Múltiplas/genética , DNA Helicases/genética , Face/anormalidades , Deformidades Congênitas da Mão/genética , Cardiopatias/genética , Deficiência Intelectual/genética , Micrognatismo/genética , Modelos Moleculares , Pescoço/anormalidades , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/patologia , Face/patologia , Deformidades Congênitas da Mão/diagnóstico , Deformidades Congênitas da Mão/patologia , Cardiopatias/congênito , Cardiopatias/diagnóstico , Cardiopatias/patologia , Humanos , Recém-Nascido , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/patologia , Masculino , Micrognatismo/diagnóstico , Micrognatismo/patologia , Mutação , Pescoço/patologia
13.
Vestn Otorinolaringol ; 84(2): 65-69, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31198219

RESUMO

This article reports the results of the main fields of the scientific activities carried out by the research personnel of the Department of Otorhinolaryngology of the Rostov State Medical University. In addition the data on the history of the Department are presented beginning from the time of its foundation, together with the characteristic of its ongoing work and the main tendencies of its further development. The most important publications of the scientists of the Department are listed, the new research areas and prospects for the future studies and practical works along these lines are discussed.


Assuntos
Otolaringologia , Universidades , Moscou , Pesquisa
14.
Artigo em Inglês | MEDLINE | ID: mdl-30886116

RESUMO

ß-Mannosidosis is a lysosomal storage disorder characterized by accumulation of disaccharides due to deficiency of the lysosomal enzyme ß-mannosidase. The disease is caused by mutations in MANBA and is extremely rare in humans. Although the clinical presentation is heterogeneous, common symptoms include various degrees of developmental delay, behavioral disturbances, hearing loss, and frequent infections. We report a 15-yr-old girl presenting with mild intellectual disability, sensorineural hearing loss, severe behavioral disturbances, dysmorphic traits, and evolving angiokeratomas. Copy-number variation analysis of next-generation sequencing (NGS) data indicated increased coverage in exons 8-11 of MANBA Low ß-mannosidase activity (1 µkatal/kg protein, refv 25-40) established the diagnosis of ß-mannosidosis. Whole-genome sequencing (WGS) and cDNA analysis revealed a novel homozygous intragenic inverted duplication in MANBA, where a 13.1-kb region between introns 7 and 11 was duplicated and inserted in an inverted orientation, creating a 67-base nonduplicated gap at the insertion point. Both junctions showed microhomology regions. The inverted duplication resulted in exon skipping of exons 8-9 or 8-10. Our report highlights the importance of copy-number variation analysis of data from NGS and in particular the power of WGS in the identification and characterization of copy-number variants.


Assuntos
Angioceratoma/genética , Variações do Número de Cópias de DNA , Manosidases/genética , beta-Manosidose/genética , Adolescente , Angioceratoma/diagnóstico , Angioceratoma/patologia , DNA Complementar/genética , Éxons/genética , Feminino , Duplicação Gênica , Perda Auditiva/genética , Sequenciamento de Nucleotídeos em Larga Escala , Homozigoto , Humanos , Deficiência Intelectual/genética , Mutação , Fenótipo , Análise de Sequência de DNA , Sequenciamento Completo do Genoma , beta-Manosidose/diagnóstico , beta-Manosidose/patologia
15.
Br J Neurosurg ; 33(3): 305-308, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29160113

RESUMO

Objective: To report 2 cases of superficial siderosis of central nervous system (SS-CNS) and a review of the literature. Methods: We have analyzed the clinical data and relevant features of two patients with SS-CNS who were presented with ataxia and slurred speech. Both patients undertook blood tests, lumbar puncture, head CT (computer tomography) scans, and brain and spinal cord magnetic resonance (MR) scans. In addition, the first patient also undewent enhanced susceptibility-weighted angiography (ESWAN) and the second patient undertook susceptibility weighted imaging (SWI) scan. We searched PubMed with the keywords superficial siderosis and superficial siderosis of central nervous system, and selected publications that seemed appropriate. Results: A neurological examination revealed bilateral sensorineural hearing impairment in both the patients. Their past history was not significant to identify hemorrhage. Brain MR scans demonstrated typical hypointensity rimming at the brain surface on T2 weighted images. The patients were diagnosed with SS-CNS. Conclusion: SS-CNS should be highly suspected in patients with progressive sensorineural hearing loss, ataxia, and signs of pyramidal tracts, and MR scans of brain and whole spinal cord should be undertaken to confirm the diagnosis. Advanced MRI techniques such as SWI and ESWAN are helpful in making the diagnosis of SS-CNS. The cause of hemorrhage is not identified in most cases.


Assuntos
Doenças do Sistema Nervoso Central/etiologia , Siderose/etiologia , Angiografia/métodos , Encefalopatias/etiologia , Encefalopatias/patologia , Sistema Nervoso Central/patologia , Doenças do Sistema Nervoso Central/patologia , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/patologia , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Neurossensorial/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tratos Piramidais , Siderose/patologia , Distúrbios da Fala/etiologia , Distúrbios da Fala/patologia , Punção Espinal/métodos , Tomografia Computadorizada por Raios X
16.
Artigo em Inglês | MEDLINE | ID: mdl-30446579

RESUMO

Using clinical exome sequencing (ES), we identified an autosomal recessive missense variant, c.153C>A (p.F51L), in the peroxisome biogenesis factor 26 gene (PEX26) in a 19-yr-old female of Ashkenazi Jewish descent who was referred for moderate to severe hearing loss. The proband and three affected siblings are all homozygous for the c.153C>A variant. Skin fibroblasts from this patient show normal morphology in immunostaining of matrix proteins, although the level of catalase was elevated. Import rate of matrix proteins was significantly decreased in the patient-derived fibroblasts. Binding of Pex26-F51L to the AAA ATPase peroxins, Pex1 and Pex6, is severely impaired and affects peroxisome assembly. Moreover, Pex26 in the patient's fibroblasts is reduced to ∼30% of the control, suggesting that Pex26-F51L is unstable in cells. In the patient's fibroblasts, peroxisome-targeting signal 1 (PTS1) proteins, PTS2 protein 3-ketoacyl-CoA thiolase, and catalase are present in a punctate staining pattern at 37°C and in a diffuse pattern at 42°C, suggesting that these matrix proteins are not imported to peroxisomes in a temperature-sensitive manner. Analysis of peroxisomal metabolism in the patient's fibroblasts showed that the level of docosahexaenoic acid (DHA) (C22:6n-3) in ether phospholipids is decreased, whereas other lipid metabolism, including peroxisomal fatty acid ß-oxidation, is normal. Collectively, the functional data support the mild phenotype of nonsyndromic hearing loss in patients harboring the F51L variant in PEX26.


Assuntos
Perda Auditiva/genética , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Peroxissomos/metabolismo , Síndrome de Zellweger/genética , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Sequência de Aminoácidos , Feminino , Perda Auditiva/metabolismo , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Linhagem , Ligação Proteica , Estabilidade Proteica , Análise de Sequência de DNA , Síndrome , Adulto Jovem , Síndrome de Zellweger/metabolismo
18.
Vestn Otorinolaringol ; 83(3): 20-24, 2018.
Artigo em Russo | MEDLINE | ID: mdl-29953049

RESUMO

The relevance of the problem of a sensorineural hearing loss (ASNL) arises from the necessity of the special approaches to the diagnostics of this condition, the complications accompanying this pathology, and the difficulties encountered in the implementation of the methods designed for hearing rehabilitation of such patients. The objective of the present study was to estimate the prevalence of ASHL among the adult population. The sensorineural impairment of hearing was diagnosed in a total of 2456 (72%) examined patients presenting with hearing loss. To determine the presence of asymmetry of sensorineural hearing loss, we employed three counting techniques allowing (1) to calculate the difference between the average hearing thresholds at four frequencies within the range from 0.5 to 4 kHz (the difference was found to be 15 dB or more in 17% of the patients), (2) to calculate the difference between the degrees of hearing loss in the right and left ears (the difference was documented in 47% of the patients), (3) to calculate the difference between the hearing thresholds at least at a single frequency within the range from 0.125 to 8 kHz (he difference was found to be 15 dB or more in 71% of the patients). When using the third method to characterize asymmetry of hearing impairment, it was identified in most patients (53%) at one or two frequencies. Moreover, there was a large number of the patients (13%) with asymmetry apparent over the entire frequency range. A high degree of threshold asymmetry (in excess of 40 dB) was more often noted in the mid-frequency range. In the majority of the patients, the asymmetry manifested itself as the different degree of bilateral sensorineural hearing impairment (51%) or unilateral sensorineural hearing loss with the normal hearing ability preserved in the contralateral ear (35%). The results of the present study give evidence of the necessity of developing a reliable method for the identification of clinically significant ACNL.


Assuntos
Correção de Deficiência Auditiva/métodos , Perda Auditiva Neurossensorial , Perda Auditiva Unilateral , Testes Auditivos , Adulto , Idoso , Limiar Auditivo , Feminino , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/epidemiologia , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Neurossensorial/reabilitação , Perda Auditiva Unilateral/diagnóstico , Perda Auditiva Unilateral/epidemiologia , Perda Auditiva Unilateral/fisiopatologia , Perda Auditiva Unilateral/reabilitação , Testes Auditivos/métodos , Testes Auditivos/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Federação Russa/epidemiologia
19.
Vestn Otorinolaringol ; 83(2): 4-8, 2018.
Artigo em Russo | MEDLINE | ID: mdl-29697645

RESUMO

The objective of the present study was to evaluate to what degree the function of the central auditory pathways influences the intelligibility of the speech in the patients suffering from the sensorineural loss of hearing (SNLH). The study included a total of 20 patients at the age varying from 31 to 80 years presenting with moderate to moderately severe symmetrical SNLN. All the patients were permanent hearing aid users. They underwent the standard audiological examination including pure-tone threshold and suprathreshold audimetries together with impedancemetry, the evaluation of the functional ability of the central auditory pathways with special reference to temporal resolution and differential frequency sensitivity, binaural integration, and the ability to distinguish a sound stimulus against the background noise. It has been found that the impaired intelligibility of the speech and the decreased efficiency of the hearing aids in the patients presenting with SNLH were attributable to the central auditory pathway disorders detected in 50% of the participants in the study. The strong correlation between the results of detection of the stimulus under conditions of tonal signal interference, the binaural integration test, and intelligibility of the speech in the users of hearing aids was documented.


Assuntos
Inteligibilidade da Fala/fisiologia , Adulto , Idoso , Audiometria de Tons Puros/métodos , Limiar Auditivo , Feminino , Auxiliares de Audição , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Neurossensorial/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Fisiológico de Modelo , Testes de Discriminação da Fala/métodos , Resultado do Tratamento
20.
J Pediatr ; 199: 144-150.e1, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29681450

RESUMO

OBJECTIVE: To evaluate the feasibility and potential benefits of incorporating genetic and cytomegalovirus (CMV) screenings into the current newborn hearing screening (NHS) programs. STUDY DESIGN: Newborns were recruited prospectively from a tertiary hospital and a maternity clinic between May 2016 and December 2016 and were subjected to hearing screening, CMV screening, and genetic screening for 4 common mutations in deafness genes (p.V37I and c.235delC of GJB2 gene, c.919-2A>G of SLC26A4 gene, and the mitochondrial m.1555A>G). Infants with homozygous nuclear mutations or homoplasmic/heteroplasmic mitochondrial mutation (referred to as "conclusively positive genotypes") and those who tested positive for CMV received diagnostic audiologic evaluations. RESULTS: Of the total 1716 newborns enrolled, we identified 20 (1.2%) newborns with conclusively positive genotypes on genetic screening, comprising 15 newborns (0.9%) with GJB2 p.V37I/p.V37I and 5 newborns (0.3%) with m.1555A>G. Three (0.2%) newborns tested positive on CMV screening. Twelve of the 20 newborns (60%) with conclusively positive genotypes and all 3 newborns who tested positive for CMV (100%) passed NHS at birth. Diagnostic audiologic evaluations conducted at 3 months confirmed hearing impairment in 6 of the 20 infants (30%) with conclusively positive genotypes. CONCLUSIONS: This study confirms the feasibility of performing hearing, genetic, and CMV screenings concurrently in newborns and provides evidence that the incorporation of these screening tests could potentially identify an additional subgroup of infants with impaired hearing that might not be detected by the NHS programs.


Assuntos
Audiometria , Infecções por Citomegalovirus/diagnóstico , Surdez/diagnóstico , Testes Genéticos/métodos , Triagem Neonatal/métodos , Surdez/genética , Estudos de Viabilidade , Feminino , Seguimentos , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Recém-Nascido , Masculino , Mutação , Estudos Prospectivos , Taiwan
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