Explore the vast range of titles available.

Treacher Collins syndrome (TCS) is a rare autosomal dominant mandibulofacial dysostosis, with a prevalence of 0.2–1/10,000. Features include bilateral and symmetrical malar and mandibular hypoplasia and facial abnormalities due to abnormal neural crest cell (NCC) migration and differentiation. To date, three genes have been identified: TCOF1, POLR1C, and POLR1D. Despite a large number of patients with a molecular diagnosis, some remain without a known genetic anomaly. We performed exome sequencing for four individuals with TCS but who were negative for pathogenic variants in the known causative genes. The effect of the pathogenic variants was investigated in zebrafish. We identified three novel pathogenic variants in POLR1B. Knockdown of polr1b in zebrafish induced an abnormal craniofacial phenotype mimicking TCS that was associated with altered ribosomal gene expression, massive p53-associated cellular apoptosis in the neuroepithelium, and reduced number of NCC derivatives. Pathogenic variants in the RNA polymerase I subunit POLR1B might induce massive p53-dependent apoptosis in a restricted neuroepithelium area, altering NCC migration and causing cranioskeletal malformations. We identify POLR1B as a new causative gene responsible for a novel TCS syndrome (TCS4) and establish a novel experimental model in zebrafish to study POLR1B-related TCS.

Dysregulation of T follicular helper (Tfh) and T follicular regulatory (Tfr) cell homeostasis in germinal centers (GCs) can lead to antibody-mediated autoimmunity. While IL-1β modulates the GC response via IL-1R1 and IL-1R2 receptors on follicular T cells in animal models, its role in humans remains unclear. We analyzed Tfh and Tfr phenotypes in human secondary lymphoid organs (tonsils, spleen, and mesenteric lymph nodes) using flow cytometry, single-cell transcriptomics, and in vitro culture, comparing findings with samples from autoimmune patients. We observed organ-specific Tfh/Tfr phenotypes according to activation status and IL-1 receptor expression. An excess of IL-1R1 over IL-1R2 expression promoted a unique activated Tfr subset with Treg and GC-Tfh features. IL-1β signaling via IL-1R1 enhanced follicular T cell activation and Tfh-to-Tfr differentiation, while IL-1β inhibition upregulated IL-1R1, indicating a tightly regulated process. In autoimmune patients, high IL-1β and circulating Tfr levels correlated with increased autoantibody production, linking inflammation, IL-1β signaling, and Tfr/Tfh balance. Our findings highlight the critical role of IL-1β in follicular T cell activation and suggest that targeting IL-1β signaling in Tfh and Tfr cells could be a promising strategy for treating antibody-mediated autoimmune diseases.

In practice, clinical genetics bring together two main activities: etiological diagnosis and genetic counseling performed in specialized hospital departments. Since 2004, centers aiming at the diagnosis, management, training and research in the field of rare diseases (reference centers for rare diseases) have been built in several European countries. [...]the narcissistic injury caused by the passage from the dreamed child to the real child causes high expectations of understanding from parents. [...]during the genetic consultation, preconceived ideas, sometimes rooted for a long time in the family’s imagination, resurface. To date, the goals of genetic evaluation of a CSHI are multiple: -. to establish the etiology of the hearing impairment; -. to identify associated features; -. to establish a prognosis of the hearing impairment; -. to improve the management of hearing loss; -. to evaluate the recurrence risk in parents’ and patient’s offspring (genetic counseling); -. to detect possibly other affected subjects within the family. Audiograms of the siblings to diagnose familial cases of variable severity or progressive hearing loss and other family members if indicated by pedigree analysis. 4.

Objective Unilateral labyrinthectomy (UL) and unilateral vestibular neurectomy (UVN) are two surgical methods to produce vestibular lesions in the mouse. The objective of this study was to describe the surgical technique of both methods, and compare functional compensation using vestibulo-ocular reflex-based tests. Methods UL and UVN were each performed on groups of seven and ten mice, respectively. Main surgical landmarks were the facial nerve, the external auditory canal and the sternomastoid and digastric muscles. For UL, the sternomastoid muscle was elevated to expose the mastoid, which was drilled to destroy the labyrinth. For UVN, the bulla was drilled opened and a transcochlear approach enabled the identification of the vestibulo-cochlear nerve exiting the brainstem, which was sectioned and the ganglion of Scarpa suctioned. Behaviour and vestibular function were analysed before surgery and at 1, 4, 7 days and at 1 month postlesion using sinusoidal rotation, off-vertical axis rotation, static head tilts and angular velocity steps. Results UL is a faster and safer procedure than UVN (operative time 16.3 vs 20.5 min, p  = 0.19; survival rate 86% vs 60%, p  = 0.25). UVN was more severe with significantly worse behavioural scores at day 4 and day 7 ( p  < 0.001). Vestibular compensation was overall similar during the first week and at 1 month (non-statistically significant difference). Conclusion Both UL and UVN procedures can routinely be performed in the mouse with similar post-operative recovery and behavioural compensation. The operative risk of vascular or neurological damage is smaller in UL compared to UVN. UVN may be required for specific research protocols studying central cellular process specifically related to the destruction of the ganglion of Scarpa and following vestibular nerve degeneration.

Purpose Videos and images are becoming an educational tool in every domain. The objective was to assess the contribution of short educational endoscopic videos in learning the complex anatomy of the tympanic cavity. Methods We conducted a prospective study amongst all the otolaryngology residents in 2021 in the greater Paris area ( n  = 74), from the first year to fifth year. We divided the residents into two groups who had the same 30-min anatomy class based on anatomical drawings. The second group had a 4-min endoscopic educational video at the end, whereas the first group did not. A video test of 10 surgical situations with each time 5 anatomic structures to identify was created. All the residents took the test just after the class, and 1 month later to assess long-term memory. The MERSQI score (design to assess the quality of educational studies) applied to our study was calculated. Results The two groups were comparable in terms of training. The “video” group had significantly better results in the first test, mean score 24.40/50 (± 11.7) versus 16.74/50 (± 11.1) (p = 0.005) and also at 1 month, mean score 23.25/50 (± 12.3) versus 18.01/50 (± 11.3) (p = 0.035). The score in each group, and the difference between both groups, increased with resident seniority. The MERSQI score of our study was 14.5/18. Conclusion This study highlights the educational value of videos to help memorise complex 3D anatomy such as in the tympanic cavity.

Mitochondrial DNA (mtDNA) mutations have been implicated in non-syndromic hearing loss either as primary or as predisposing factors. As only a part of the mitochondrial genome is usually explored in deafness, its prevalence is probably under-estimated. Among 1350 families with non-syndromic sensorineural hearing loss collected through a French collaborative network, we selected 29 large families with a clear maternal lineage and screened them for known mtDNA mutations in 12S rRNA, tRNASer(UCN) and tRNALeu(UUR) genes. When no mutation could be identified, a whole mitochondrial genome screening was performed, using a microarray resequencing chip: the MitoChip version 2.0 developed by Affymetrix Inc. Known mtDNA mutations was found in nine of the 29 families, which are described in the article: five with A1555G, two with the T7511C, one with 7472insC and one with A3243G mutation. In the remaining 20 families, the resequencing Mitochip detected 258 mitochondrial homoplasmic variants and 107 potentially heteroplasmic variants. Controls were made by direct sequencing on selected fragments and showed a high sensibility of the MitoChip but a low specificity, especially for heteroplasmic variations. An original analysis on the basis of species conservation, frequency and phylogenetic investigation was performed to select the more probably pathogenic variants. The entire genome analysis allowed us to identify five additional families with a putatively pathogenic mitochondrial variant: T669C, C1537T, G8078A, G12236A and G15077A. These results indicate that the new MitoChip platform is a rapid and valuable tool for identification of new mtDNA mutations in deafness.

To assess the quantitative and qualitative impact of the COVID-19 lockdown on pediatric otolaryngology emergency activity. A retrospective study was conducted in a pediatric otolaryngology tertiary care center. Emergency activity during the lockdown period from March 17 to May 11, 2020, was compared to the 2019 and 2018 averages for the same period. Study data included a number of emergency consultations and the number and type of surgical procedures: infection management, endoscopic airway procedure, and post-tonsillectomy hemorrhage. Only 350 children were referred to the pediatric otolaryngology emergencies in our center during the lockdown, compared to 761 on the same period the year before (− 54%); 62 emergency surgeries were performed, compared to 93 (− 33%). The ratio between emergency surgeries and consultations was 18% in 2020, versus 12% previously ( p  = 0.014). The number of surgical procedures for infectious diseases decreased (− 68%), at 16% of surgical emergencies in 2020 compared to 33% previously ( p  = 0.017). In 2020, 52 emergency endoscopies were performed, versus 59 previously (− 12%), 27% being performed for suspected tracheobronchial or esophageal foreign bodies, compared to 66% in previous years ( p  < 0.0001). No post-tonsillectomy hemorrhages were managed in 2020. Conclusion : The COVID-19 lockdown changed pediatric ENT emergency activity quantitatively and also qualitatively. What is Known: • SARS-CoV-2 pandemic impacted pediatric ENT emergency activity quantitatively and qualitatively. What is New: • here was a 54% decrease in pediatric ENT emergency consultation and 33% decrease in emergency ENT surgeries. • Rates of surgery for infection of whatever type decreased by 68%.

BackgroundOculo-auriculo-vertebral spectrum (OAVS) is a developmental disorder involving first and second branchial arches derivatives, mainly characterised by asymmetric ear anomalies, hemifacial microsomia, ocular defects and vertebral malformations. Although numerous chromosomal abnormalities have been associated with OAVS, no causative gene has been identified so far.ObjectivesWe aimed to identify the first causative gene for OAVS.MethodsAs sporadic cases are mostly described in Goldenhar syndrome, we have performed whole exome sequencing (WES) on selected affected individuals and their unaffected parents, looking for de novo mutations. Candidate gene was tested through transient knockdown experiment in zebrafish using a morpholino-based approach. A functional test was developed in cell culture in order to assess deleterious consequences of mutations.ResultsBy WES, we identified a heterozygous nonsense mutation in one patient in the myelin transcription factor 1 (MYT1) gene. Further, we detected one heterozygous missense mutation in another patient among a cohort of 169 patients with OAVS. This gene encodes the MYT1. Functional studies by transient knockdown of myt1a, homologue of MYT1 in zebrafish, led to specific craniofacial cartilage alterations. Treatment with all-trans retinoic acid (RA), a known teratogenic agent causing OAVS, led to an upregulation of cellular endogenous MYT1 expression. Additionally, cellular wild-type MYT1 overexpression induced a downregulation of RA receptor β (RARB), whereas mutated MYT1 did not.ConclusionWe report MYT1 as the first gene implicated in OAVS, within the RA signalling pathway.

Purpose to assess audiological performance in quiet and noise, quality of life and side effects of Vibrant Soundbridge (VSB) in children with congenital aural atresia (CAA). Methods A retrospective study including consecutive patients with unilateral or bilateral CAA implanted with VSB from 2009 to 2020 in a tertiary referral centre. Results 18 patients with CAA and a present stapes were included (3 simultaneous bilateral VSB implants) and 21 ears: 17 VSB were attached to the short incus process, and four to the stapes. Age at implantation ranged from 4.7 to 15.8 years. Average follow-up was 6.5 years (± 3.7 years). In unilateral VSB, air conduction pure tone average (ACPTA) thresholds increased from 75.3 ± 15.2 to 32.6 ± 8.3 dB post-operatively (VSB activated) ( n  = 15; p  < 0.01). The speech reception threshold (SRT) and the word recognition score (WRS) were significantly improved from 81.5 ± 10.4 to 43.9 ± 7.6 dB and 0% to 84.8 ± 8.5% postoperatively ( n  = 15; p  < 0.01). The signal to noise ratio (SNR) was significantly improved from 2.1 ± 2.9 dB VSB inactivated to 0.3 ± 2.7 dB VSB activated ( n  = 15; p  < 0.01). There was no significant difference in performance according to floating mass transducer (FMT) placement. 5/15 children were non-users at last follow-up in unilateral VSB and 0/3 in bilateral. Conclusions CAA ears with VSB activated had a significant improvement of ACPTA, WRS, SRT and SNR. A third of patients with unilateral CAA became non-users at last follow-up. The main challenge is to target the indications for the implantation of the VSB to avoid its discontinuation.

Purpose Auditory processing disorder (APD) may affect 0.2–5% of the paediatric population. The diagnosis of APD remains difficult because of polymorphic symptoms possibly entangled with other difficulties. The purpose of this study was to evaluate a new multi-disciplinary assessment in the French language. Methods The battery of tests was composed of: (a) APD targeted speech assessment: speech perception in noise, a dichotic test, temporal processing tests (patterns); (b) Psychometric assessment: sustained auditory attention, sustained visual attention, evaluation of cognitive functions; (c) phonemic identification and discrimination; (d) ENT examination, tonal and vocal audiometry and ABR recordings. The diagnosis was made if two of the targeted speech tests were 2 standard deviations (SDs) below the mean or if only one of the tests was 3 SDs below. The auditory attention tests, as well as the phonemic identification and discrimination tests were complementary to the diagnostic battery. However, they did not allow for the diagnosis of APD. Results 50 children suspected of APD benefited from this protocol, and 12 were excluded from the study. A diagnosis of APD was confirmed in 17 children (45%). 59% of the patients had associated disorders. The most effective tests for diagnosing APD were dichotic testing ( p  = 0.001) and pattern recognition (frequency, p  = 0.001). The sustained auditory attention test ( p  = 0.01) and the phonemic identification and discrimination test reinforced the diagnosis of APD. Conclusion It seems important to evaluate children suspected of APD with a multi-disciplinary protocol. It makes it possible to diagnose APD children, but also to identify attentional difficulties and cognitive disorders that may be associated.