Hearing impairment (HI) affects 1 in 650 newborns, which makes it the most common congenital sensory impairment. Despite extraordinary genetic heterogeneity, mutations in one gene, GJB2, which encodes the connexin 26 protein and is involved in inner ear homeostasis, are found in up to 50% of patients with autosomal recessive nonsyndromic hearing loss. Because of the high frequency of GJB2 mutations, mutation analysis of this gene is widely available as a diagnostic test. In this study, we assessed the association between genotype and degree of hearing loss in persons with HI and biallelic GJB2 mutations. We performed cross-sectional analyses of GJB2 genotype and audiometric data from 1,531 persons, from 16 different countries, with autosomal recessive, mildto-profound nonsyndromic HI. The median age of all participants was 8 years; 90% of persons were within the age range of 0-26 years. Of the 83 different mutations identified, 47 were classified as nontruncating, and 36 as truncating. A total of 153 different genotypes were found, of which 56 were homozygous truncating (T/T), 30 were homozygous nontruncating (NT/NT), and 67 were compound heterozygous truncating/nontruncating (T/ NT). The degree of HI associated with biallelic truncating mutations was significantly more severe than the HI associated with biallelic nontruncating mutations (). The HI of 48 different genotypes was less severe P ! .0001 than that of 35delG homozygotes. Several common mutations (M34T, V37I, and L90P) were associated with mildto-moderate HI (median 25-40 dB). Two genotypes-35delG/R143W (median 105 dB) and 35delG/dela(GJB6-D13S1830) (median 108 dB)-had significantly more-severe HI than that of 35delG homozygotes.
Usher syndrome type IIa (USHIIa) is an autosomal recessive disorder characterized by moderate to severe sensorineural hearing loss and progressive retinitis pigmentosa. This disorder maps to human chromosome 1q41. Recently, mutations in USHIIa patients were identified in a novel gene isolated from this chromosomal region. The USH2A gene encodes a protein with a predicted molecular weight of 171.5 kD and possesses laminin epidermal growth factor as well as fibronectin type III domains. These domains are observed in other protein components of the basal lamina and extracellular matrixes; they may also be observed in cell-adhesion molecules. The intron/exon organization of the gene whose protein we name "Usherin" was determined by direct sequencing of PCR products and cloned genomic DNA with cDNA-specific primers. The gene is encoded by 21 exons and spans a minimum of 105 kb. A mutation search of 57 independent USHIIa probands was performed with a combination of direct sequencing and heteroduplex analysis of PCR-amplified exons. Fifteen new mutations were found. Of 114 independent USH2A alleles, 58 harbored probable pathologic mutations. Ten cases of USHIIa were true homozygotes and 10 were compound heterozygotes; 18 heterozygotes with only one identifiable mutation were observed. Sixty-five percent (38/58) of cases had at least one mutation, and 51% (58/114) of the total number of possible mutations were identified. The allele 2299delG (previously reported as 2314delG) was the most frequent mutant allele observed (16%; 31/192). Three new missense mutations (C319Y, N346H, and C419F) were discovered; all were restricted to the previously unreported laminin domain VI region of Usherin. The possible significance of this domain, known to be necessary for laminin network assembly, is discussed in the context of domain VI mutations from other proteins.
Aims/Hypothesis: Idiopathic sudden sensorineural hearing loss (ISSNHL) represents an acute inner ear disorder with an overall incidence of 5–20/100000 individuals per year in western countries. No clear causes for this disease have been found so far, but cochlear ischemia has been hypothesized as one of the etiopathological mechanisms. The aim of our study was to assess the role of diabetes and traditional cardiovascular risk factors in the pathogenesis of ISSNHL. Materials/Methods: Case-control study of 141 patients (75 males/66 females) matched for age and gender. Cases were affected by ISSNHL, defined as a sudden hearing loss ≧30 dB, within 3 frequencies, developing over 72 h. The control group was composed of 271 sex- and age-matched subjects (142 males/129 females) who agreed to participate in this observational study and provided blood samples for laboratory investigations. Cardiovascular risk factors examined were: diabetes mellitus, smoking history, hypercholesterolemia, hypertriglyceridemia and hypertension. Results: On the univariate analysis, diabetes prevalence was higher in the ISSNHL group (15.6%) compared to controls (8.5%) (p = 0.03). Also hypercholesterolemia was significantly more frequent in the ISSNHL group compared to the control population. There were no statistically significant differences between the 2 populations concerning other cardiovascular risk factors. The risk of ISSNHL tended to increase as the number of cardiovascular risk factors increased (p for linear trend = 0.018). Conclusions: Our findings suggest that diabetes mellitus, hypercholesterolemia and a high burden of cardiovascular risk factors are associated with the risk of ISSNHL.
A growing interest in cognitive effects associated with speech and hearing processes is spreading throughout the scientific community essentially guided by evidence that central and peripheral hearing loss is associated with cognitive decline. For the present research, 125 participants older than 65 years of age (105 with hearing impairment and 20 with normal hearing) were enrolled, divided into 6 groups according to their degree of hearing loss and assessed to determine the effects of the treatment applied. Patients in our research program routinely undergo an extensive audiological and cognitive evaluation protocol providing results from the Digit Span test, Stroop color-word test, Montreal Cognitive Assessment and Geriatric Depression Scale, before and after rehabilitation. Data analysis was performed for a cross-sectional and longitudinal study of the outcomes for the different treatment groups. Each group demonstrated improvement after auditory rehabilitation or training on short- and long-term memory tasks, level of depression and cognitive status scores. Auditory rehabilitation by cochlear implants or hearing aids is effective also among older adults (median age of 74 years) with different degrees of hearing loss, and enables positive improvements in terms of social isolation, depression and cognitive performance.
Cisplatin is the most common antineoplastic drug used for the therapy of solid tumours. To date, researchers have focused on the dosage to be administered for each specific tumour, mainly considering the local adverse effects. The aim of this study was to correlate the severity of the adverse effects with: i) the dosage of cisplatin; ii) the specific site of the tumour; iii) the association with other drugs; and iv) the symptoms. We analysed data from 123 patients with 11 different tumour classes undergoing therapy from 2007 to 2008 at St. Anna Hospital (Ferrara, Italy), using the Spearman non-parametric correlation index. Even though significant correlations were found among the variables, the overall results showed that the main factor influencing the severity of the adverse effects was the dosage of cisplatin administered.
Recurrences occurred despite obtaining block resections according to the tumor's clinical stage and pathologically free margins in all cases. Further analyses are mandatory to investigate hidden microscopic pathways of tumor diffusion, particularly in bone. Multi-institutional protocols are needed to facilitate comparisons between studies and enable meaningful meta-analyses.
Temporal bone carcinoma is an uncommon aggressive malignancy. Its low incidence and the absence of a globally accepted staging system still make it difficult to compare different centers' approaches and results. In this review of the main available studies dealing with temporal bone carcinoma since 1995, we consider its rational preoperative staging and assessment, compare the effectiveness of different treatments by tumor stage, and outline the main actuarial prognostic factors.
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