Generation of four induced pluripotent stem cells lines from PBMC of the DFNA58 family members: Two hearing-impaired duplication carriers (USPi006-A e USPi007-A) and two normal-hearing noncarriers (USPi004-A and USPi005-A).

The DFNA58 locus contains a genomic duplication involving three protein-coding genes (CNRIP1, PLEK, and PPP3R1's exon 1) and other uncharacterized lncRNA genes (LOC101927723, LOC107985892 and LOC102724389). To clarify the role of these genes in hearing and precisely determine their role in hearing loss, four iPSC lines were generated from two carriers and two noncarriers of the duplication.

Clinical, sociodemographic and environmental factors impact post-COVID-19 syndrome.

Background: Sociodemographic and environmental factors are associated with incidence, severity, and mortality of COVID-19. However, little is known about the role of such factors in persisting symptoms among recovering patients. We designed a cohort study of hospitalized COVID-19 survivors to describe persistent symptoms and identify factors associated with post-COVID-19 syndrome. Methods: We included patients hospitalized between March to August 2020 who were alive six months after hospitalization. We collected individual and clinical characteristics during hospitalization and at follow-up assessed ten symptoms with standardized scales, 19 yes/no symptoms, a functional status and a quality-of-life scale and performed four clinical tests. We examined individual exposure to greenspace and air pollution and considered neighbourhood´s population density and socioeconomic conditions as contextual factors in multilevel regression analysis. Results: We included 749 patients with a median follow-up of 200 (IQR = 185-235) days, and 618 (83%) had at least one of the ten symptoms measured with scales. Pain (41%), fatigue (38%) and posttraumatic stress disorder (35%) were the most frequent. COVID-19 severity, comorbidities, BMI, female sex, younger age, and low socioeconomic position were associated with different symptoms. Exposure to ambient air pollution was associated with higher dyspnoea and fatigue scores and lower functional status. Conclusions: We identified a high frequency of persistent symptoms among COVID-19 survivors that were associated with clinical, sociodemographic, and environmental variables. These findings indicate that most patients recovering from COVID-19 will need post-discharge care, and an additional burden to health care systems, especially in LMICs, should be expected.

Post-acute sequelae of SARS-CoV-2 infection: relationship of central nervous system manifestations with physical disability and systemic inflammation.

BACKGROUND: Despite the multitude of clinical manifestations of post-acute sequelae of SARS-CoV-2 infection (PASC), studies applying statistical methods to directly investigate patterns of symptom co-occurrence and their biological correlates are scarce. METHODS: We assessed 30 symptoms pertaining to different organ systems in 749 adults (age = 55 ± 14 years; 47% female) during in-person visits conducted at 6-11 months after hospitalization due to coronavirus disease 2019 (COVID-19), including six psychiatric and cognitive manifestations. Symptom co-occurrence was initially investigated using exploratory factor analysis (EFA), and latent variable modeling was then conducted using Item Response Theory (IRT). We investigated associations of latent variable severity with objective indices of persistent physical disability, pulmonary and kidney dysfunction, and C-reactive protein and D-dimer blood levels, measured at the same follow-up assessment. RESULTS: The EFA extracted one factor, explaining 64.8% of variance; loadings were positive for all symptoms, and above 0.35 for 16 of them. The latent trait generated using IRT placed fatigue, psychiatric, and cognitive manifestations as the most discriminative symptoms (coefficients > 1.5, p < 0.001). Latent trait severity was associated with decreased body weight and poorer physical performance (coefficients > 0.240; p ⩽ 0.003), and elevated blood levels of C-reactive protein (coefficient = 0.378; 95% CI 0.215-0.541; p < 0.001) and D-dimer (coefficient = 0.412; 95% CI 0.123-0.702; p = 0.005). Results were similar after excluding subjects with pro-inflammatory comorbidities. CONCLUSIONS: Different symptoms that persist for several months after moderate or severe COVID-19 may unite within one latent trait of PASC. This trait is dominated by fatigue and psychiatric symptoms, and is associated with objective signs of physical disability and persistent systemic inflammation.

Noise Exposure and Distortion Product Otoacoustic Emission Suprathreshold Amplitudes: A Genome-Wide Association Study.

BACKGROUND: Although several candidate-gene association studies have been conducted to investigate noise-induced hearing loss (NIHL) in humans, most are underpowered, unreplicated, and account for only a fraction of the genetic risk. Mouse genome-wide association studies (GWASs) have revolutionized the field of genetics and have led to the discovery of hundreds of genes involved in complex traits. The hybrid mouse diversity panel (HMDP) is a collection of classic inbred and recombinant inbred strains whose genomes have been either genotyped at high resolution or sequenced. To further investigate the genetics of NIHL, we report the first GWAS based on distortion product otoacoustic emission (DPOAE) measurements and the HMDP. METHODS: A total of 102 strains (n = 635) from the HMDP were evaluated based on DPOAE suprathreshold amplitudes before and after noise exposure. DPOAE amplitude variation was set at 60 and 70 dB SPL of the primary tones for each frequency separately (8, 11.3, 16, 22.6, and 32 kHz). These values provided an indirect assessment of outer hair cell integrity. Six-week-old mice were exposed for 2 h to 10 kHz octave-band noise at 108 dB SPL. To perform local expression quantitative trait locus (eQTL) analysis, gene expression microarray profiles were generated using cochlear RNA from 64 hybrid mouse strains (n = 3 arrays per strain). RESULTS: Several new loci were identified and positional candidate-genes associated with NIHL were prioritized, especially after noise exposure (1 locus at baseline and 5 loci after exposure). A total of 35 candidate genes in these 6 loci were identified with at least 1 probe whose expression was regulated by a significant cis-eQTL in the cochlea. After careful analysis of the candidate genes based on cochlear gene expression, 2 candidate genes were prioritized: Eya1 (baseline) and Efr3a (post-exposure). DISCUSSION AND CONCLUSION: For the first time, an association analysis with correction for population structure was used to map several loci for hearing traits in inbred strains of mice based on DPOAE suprathreshold amplitudes before and after noise exposure. Our results identified a number of novel loci and candidate genes for susceptibility to NIHL, especially the Eya1 and Efr3a genes. Our findings validate the power of the HMDP for detecting NIHL susceptibility genes.

Impact of the COVID-19 Pandemic on Physicians Working in the Head and Neck Field.

Background With the COVID-19 pandemic, the clinical practice of physicians who work in the head and neck field in Brazil dropped dramatically. The sustained impact of the pandemic is not known. Methods An anonymous online survey was distributed to Brazilian otolaryngologists, head and neck surgeons, medical and radiation oncologists, asking about their clinical practice in the third to fourth months of the pandemic. Results The survey was completed by 446 specialists. About 40% reported reduction of more than 75% in outpatient care. A reduction of 90% to 100% in airway endoscopies was reported by 50% of the responders, and the same rate of reduction regarding surgeries (pediatric or nasosinusal) was reported by 80% of them. Family income decreased by 50%, and the psychological burden on physicians was considerable. The availability of personal protective equipment and safety precautions were limited, especially in the public sector. Conclusion COVID-19 is still impacting the head and neck field, and safety concerns may hinder the prompt resumption of elective care.

Impact of the COVID-19 Pandemic on Physicians Working in the Head and Neck Field

Abstract Background With the COVID-19 pandemic, the clinical practice of physicians who work in the head and neck field in Brazil dropped dramatically. The sustained impact of the pandemic is not known. Methods An anonymous online survey was distributed to Brazilian otolaryngologists, head and neck surgeons, medical and radiation oncologists, asking about their clinical practice in the third to fourth months of the pandemic. Results The survey was completed by 446 specialists. About 40 % reported reduction of more than 75 % in outpatient care. A reduction of 90 % to 100 % in airway endoscopies was reported by 50 % of the responders, and the same rate of reduction regarding surgeries (pediatric or nasosinusal) was reported by 80 % of them. Family income decreased by 50 %, and the psychological burden on physicians was considerable. The availability of personal protective equipment and safety precautions were limited, especially in the public sector. Conclusion COVID-19 is still impacting the head and neck field, and safety concerns may hinder the prompt resumption of elective care.

A rare genomic duplication in 2p14 underlies autosomal dominant hearing loss DFNA58.

Here we define a ~200 Kb genomic duplication in 2p14 as the genetic signature that segregates with postlingual progressive sensorineural autosomal dominant hearing loss (HL) in 20 affected individuals from the DFNA58 family, first reported in 2009. The duplication includes two entire genes, PLEK and CNRIP1, and the first exon of PPP3R1 (protein coding), in addition to four uncharacterized long non-coding (lnc) RNA genes and part of a novel protein-coding gene. Quantitative analysis of mRNA expression in blood samples revealed selective overexpression of CNRIP1 and of two lncRNA genes (LOC107985892 and LOC102724389) in all affected members tested, but not in unaffected ones. Qualitative analysis of mRNA expression identified also fusion transcripts involving parts of PPP3R1, CNRIP1 and an intergenic region between PLEK and CNRIP1, in the blood of all carriers of the duplication, but were heterogeneous in nature. By in situ hybridization and immunofluorescence, we showed that Cnrip1, Plek and Ppp3r1 genes are all expressed in the adult mouse cochlea including the spiral ganglion neurons, suggesting changes in expression levels of these genes in the hearing organ could underlie the DFNA58 form of deafness. Our study highlights the value of studying rare genomic events leading to HL, such as copy number variations. Further studies will be required to determine which of these genes, either coding proteins or non-coding RNAs, is or are responsible for DFNA58 HL.

Distúrbios da Comunicação em Pacientes Pediátricos ­ um Algoritmo da Avaliação Audiológica / Communication Disorders in Pediatric Patients - An Algorithm of Audiological Evaluation

Introdução: Foi instituído Teste de Triagem Auditiva Neonatal Universal (TANU). Crianças podem passar no teste e apresentar surdez tardia ou progressiva ou, ainda, serem portadoras de perdas leves e moderadas que não são observadas. Objetivo: Através deste relato de caso, discutir os exames auditivos pertinentes em cada situação e a orientação dos profissionais de saúde que primeiramente recebem estes pacientes. Descrição do Caso: O caso mostra a importância da avaliação da audição para auxílio no diagnóstico. Paciente foi encaminhado por quadro de atraso de linguagem e hipótese de perda auditiva. Apresentava dificuldades na interação social e alterações comportamentais. Avaliação audiológica foi normal, sendo feito diagnóstico de transtorno de espectro autista (TEA). Comentários: Pacientes com atraso e dificuldades na comunicação podem ser difíceis de avaliar, visto que muitos dos exames auditivos são subjetivos e dependem da interação do examinador com a criança. O caso relatado mostra uma das várias situações com que os profissionais podem se deparar e revela quais são os exames adequados para uma avaliação auditiva apropriada.

Introduction: Universal Newborn Hearing Screening (UNHS) Test was instituted to detect cases with higher probability of hearing loss. Children may pass the test and have late or progressive deafness or even mild and moderate losses that are not observed. Objective: To discuss, through this report of case, the pertinent auditory exams in each situation and the orientation of the health professionals who first receive these patients. Case Description: The case shows the importance of hearing evaluation for diagnostic assistance. Case 1 was referred for language delay and hypothesis of hearing loss. He presented difficulties in social interaction and behavioral changes. Audiological evaluation was normal, being diagnosed as Autistic Spectrum Disorder (ASD). Comments: Patients with delayed communication may be difficult to assess, since many of the auditory exams are subjective and depend on the interaction of the examiner with the child. The reported case presents one of the several situations that professionals may face and reveals what examinations are appropriate for an adequate auditory assessment.

Validation of a Portuguese version of the health-related quality of life measure for active chronic otitis media (COMQ-12) / Validation of a Portuguese version of the health-related quality of life measure for active chronic otitis media (COMQ-12)

Abstract Introduction: Measuring the impact on quality of life, especially after the beginning of the treatment, is becoming increasingly important in healthcare. Objective: The aim of this study was to translate the Chronic Otitis Media Questionnaire-12 (COMQ-12) into Portuguese language and validate this version in a group of patients with chronic otitis media. Methods: The Portuguese version of COMQ-12 was obtained by translation and back translation. Portuguese speaking patients with a history of active chronic otitis media were asked to complete the COMQ-12 Portuguese version. Cronbach's α coefficient was calculated for an estimation of the internal consistency of the questionnaire. Results: A total of 100 patients were included in the study; 49 women and 51 men, with a mean age of 39 years (range 12-77 years, median 40 years). The average COMQ-12 score was 29, out of a maximum score of 60. Cronbach's α result for the Portuguese version of the COMQ-12 was 0.85, indicating a high internal consistency. The participants presented with different forms of chronic otitis media, and almost all domains of the COMQ-12 questionnaire were able to differentiate between patients with healed chronic otitis media and patients with cholesteatoma or wet tympanic membrane perforation. Showing that patients with healed chronic otitis media have a better quality of life, measured by the COMQ-12, is a first step to guarantee the questionnaire's validity. The next step will consist on routinely using the questionnaire in patients undergoing surgery for chronic otitis media in order to evaluate their quality of life after treatment. Conclusion: The COMQ-12 Portuguese version showed high reliability, and may be used as an assessment of quality of life in patients with chronic otitis media

Resumo: Introdução: Medir o impacto na qualidade de vida, especialmente após o início do tratamento dos pacientes, está se tornando cada vez mais importante nos cuidados da saúde. Objetivo: O objetivo deste estudo foi traduzir o Questionário de Otite Média Crônica-12 (COMQ-12) para a língua portuguesa e validar essa versão em um grupo de pacientes com Otite Média Crônica. Método: A versão em Língua Portuguesa do COMQ-12 foi obtida através de tradução e posterior retrotradução. Pacientes nativos da língua portuguesa com histórico de OMC ativa foram convidados a completar o COMQ-12 em Português. O coeficiente α de Cronbach foi calculado para estimar a consistência interna do questionário. Resultados: Um total de 100 pacientes foram incluídos no estudo; 49 eram mulheres e 51 eram homens, com média de idade de 39 anos (variação: 12 a 77 anos, mediana de 40 anos). O escore médio do COMQ-12 foi 29, de um escore máximo de 60. O resultado do coeficiente α de Cronbach para a versão em português do COMQ-12 foi de 0,85, indicando que sua consistência interna era alta. Os participantes apresentavam diferentes formas de otite média crônica e quase todos os domínios do questionário COMQ-12 foram capazes de diferenciar entre pacientes com otite média crônica curada e pacientes com colesteatoma ou perfuração úmida de membrana timpânica. Demonstrar que pacientes com otite média crônica curada apresentam uma melhor qualidade de vida, medida pelo COMQ-12 é o primeiro passo para garantir a validade do questionário. O próximo passo será utilizá-lo rotineiramente em pacientes submetidos à cirurgia para otite média crônica e avaliar a qualidade de vida após o tratamento. Conclusão: A versão em português do questionário COMQ-12 mostrou alta confiabilidade e pode ser utilizada como questionário de medida de qualidade de vida em pacientes com otite média crônica.

A Cell Junctional Protein Network Associated with Connexin-26.

GJB2 mutations are the leading cause of non-syndromic inherited hearing loss. GJB2 encodes connexin-26 (CX26), which is a connexin (CX) family protein expressed in cochlea, skin, liver, and brain, displaying short cytoplasmic N-termini and C-termini. We searched for CX26 C-terminus binding partners by affinity capture and identified 12 unique proteins associated with cell junctions or cytoskeleton (CGN, DAAM1, FLNB, GAPDH, HOMER2, MAP7, MAPRE2 (EB2), JUP, PTK2B, RAI14, TJP1, and VCL) by using mass spectrometry. We show that, similar to other CX family members, CX26 co-fractionates with TJP1, VCL, and EB2 (EB1 paralogue) as well as the membrane-associated protein ASS1. The adaptor protein CGN (cingulin) co-immuno-precipitates with CX26, ASS1, and TJP1. In addition, CGN co-immunoprecipitation with CX30, CX31, and CX43 indicates that CX association is independent on the CX C-terminus length or sequence. CX26, CGN, FLNB, and DAMM1 were shown to distribute to the organ of Corti and hepatocyte plasma membrane. In the mouse liver, CX26 and TJP1 co-localized at the plasma membrane. In conclusion, CX26 associates with components of other membrane junctions that integrate with the cytoskeleton.

Overcoming developing-world challenges in cochlear implantation: a South American perspective.

PURPOSE OF REVIEW: Effective hearing rehabilitation with cochlear implantation is challenging in developing countries, and this review focuses on strategies for childhood profound sensorineural hearing loss care in South America. RECENT FINDINGS: Most global hearing loss exists in developing countries; optimal cost-effective management strategies are essential in these environments. This review aims to assess and discuss the challenges of cochlear implantation effectiveness in South America. The authors searched electronic databases, bibliographies, and references for published and unpublished studies. Sensitivity analysis was performed to evaluate the effect of device cost, professional salaries, annual number of implants, and failure rate. Costs were obtained from experts in South America using known costs and estimations whenever necessary. Recent studies reported several challenges in unilateral or bilateral cochlear implants: cochlear implant costs, deaf education costs, increasing need for cochlear implant capacity, and training and increasing longevity. SUMMARY: Cochlear implantation was very cost-effective in all South American countries. Despite inconsistencies in the quality of available evidence, the robustness of systematic review methods substantiates the positive findings of the included studies, demonstrating that unilateral cochlear implantation is clinically effective and likely to be cost-effective in developing countries.

Validation of a Portuguese version of the health-related quality of life measure for active chronic otitis media (COMQ-12).

INTRODUCTION: Measuring the impact on quality of life, especially after the beginning of the treatment, is becoming increasingly important in healthcare. OBJECTIVE: The aim of this study was to translate the Chronic Otitis Media Questionnaire-12 (COMQ-12) into Portuguese language and validate this version in a group of patients with chronic otitis media. METHODS: The Portuguese version of COMQ-12 was obtained by translation and back translation. Portuguese speaking patients with a history of active chronic otitis media were asked to complete the COMQ-12 Portuguese version. Cronbach's α coefficient was calculated for an estimation of the internal consistency of the questionnaire. RESULTS: A total of 100 patients were included in the study; 49 women and 51 men, with a mean age of 39 years (range 12-77 years, median 40 years). The average COMQ-12 score was 29, out of a maximum score of 60. Cronbach's α result for the Portuguese version of the COMQ-12 was 0.85, indicating a high internal consistency. The participants presented with different forms of chronic otitis media, and almost all domains of the COMQ-12 questionnaire were able to differentiate between patients with healed chronic otitis media and patients with cholesteatoma or wet tympanic membrane perforation. Showing that patients with healed chronic otitis media have a better quality of life, measured by the COMQ-12, is a first step to guarantee the questionnaire's validity. The next step will consist on routinely using the questionnaire in patients undergoing surgery for chronic otitis media in order to evaluate their quality of life after treatment. CONCLUSION: The COMQ-12 Portuguese version showed high reliability, and may be used as an assessment of quality of life in patients with chronic otitis media.

Moving Beyond GDP: Cost Effectiveness of Cochlear Implantation and Deaf Education in Latin America.

HYPOTHESIS: Cochlear implantation (CI) and deaf education are cost effective management strategies of childhood profound sensorineural hearing loss in Latin America. BACKGROUND: CI has been widely established as cost effective in North America and Europe and is considered standard of care in those regions, yet cost effectiveness in other economic environments has not been explored. With 80% of the global hearing loss burden existing in low- and middle-income countries, developing cost effective management strategies in these settings is essential. This analysis represents the continuation of a global assessment of CI and deaf education cost effectiveness. METHODS: Brazil, Colombia, Ecuador, Guatemala, Paraguay, Trinidad and Tobago, and Venezuela participated in the study. A Disability Adjusted Life Years model was applied with 3% discounting and 10-year length of analysis. Experts from each country supplied cost estimates from known costs and published data. Sensitivity analysis was performed to evaluate the effect of device cost, professional salaries, annual number of implants, and probability of device failure. Cost effectiveness was determined using the World Health Organization standard of cost effectiveness ratio/gross domestic product per capita (CER/GDP)<3. RESULTS: Deaf education was very cost effective in all countries (CER/GDP 0.07-0.93). CI was cost effective in all countries (CER/GDP 0.69-2.96), with borderline cost effectiveness in the Guatemalan sensitivity analysis (Max CER/GDP 3.21). CONCLUSION: Both cochlear implantation and deaf education are widely cost effective in Latin America. In the lower-middle income economy of Guatemala, implant cost may have a larger impact. GDP is less influential in the middle- and high-income economies included in this study.

Caloric test as a predictor tool of postural control in CI users.

CONCLUSIONS: Balance was improved at 365 days after CI in all patients. Caloric test findings were important determinants of balance outcomes over a year after CI. Pre-operative vestibular assessment findings should be documented because postural recovery over time depends on this information. OBJECTIVE: To verify the importance of the caloric test as a pre-operative predictor tool of postural control after CI surgery. METHODS: Prospective observational study made with 24 post-lingual deafness patients who underwent unilateral CI surgery. Vestibular assessments: questionnaire assessing vertigo, caloric tests, rotary chair (RC) testing, and computerized dynamic posturography (CDP), were sequentially performed for all patients before and 60, 120, 180, and 365 days after CI. RESULTS: Thirteen patients (54.2%) reported dizziness before CI. At the end of the study, dizziness remained unchanged in one (7.7%) patient, ameliorated in 11 (84.6%), and worsened in one (7.7%). Baseline caloric tests identified 29.2% patients with normal reflexes, 33.3% with unilateral areflexia or hyporeflexia, 12.5% with bilateral hyporeflexia, and 25% with bilateral vestibular loss (BVL). Most patients exhibited objective improvements in postural stability. At 365 days, the CDP condition (particularly C5) and CS were higher for caloric tests responders at baseline than for those with BVL at baseline.

Bone marrow stem cells in facial nerve regeneration from isolated stumps.

INTRODUCTION: Severe lesions in the facial nerve may have extensive axonal loss and leave isolated stumps that impose technical difficulties for nerve grafting. METHODS: We evaluated bone marrow stem cells (BMSC) in a silicone conduit for rat facial nerve regeneration from isolated stumps. Group A utilized empty silicone tubes; in groups B-D, the tube was filled with acellular gel; and, in groups C and D, undifferentiated BMSC (uBMSC) or Schwann-like cells differentiated from BMSC (dBMSC) were added, respectively. Compound muscle action potentials (CMAPs) were measured, and histology was evaluated. RESULTS: Groups C and D had the highest CMAP amplitudes. Group C had shorter CMAP durations than groups A, B, and D. Distal axonal number and density were increased in group C compared with groups A and B. CONCLUSIONS: Regeneration of the facial nerve was improved by both uBMSC and dBMSC in rats, yet uBMSC was associated with superior functional results.

The efficacy of functional endoscopic sinus surgery in the evolution of fever of unknown origin in ICU patients.

CONCLUSION: Functional endoscopic sinus surgery (FESS) was found to be effective in treating fever of unknown origin (FUO) in intensive care unit (ICU) patients with rhinosinusitis, with 62% of patients showing improvement within 5 days of the procedure. OBJECTIVE: To correlate improvement in FUO with FESS drainage of the paranasal sinuses. METHODS: Fifty patients that developed FUO during ICU stay, with CT findings suggestive of rhinosinusitis, and showed no improvement in fever after clinical treatment underwent FESS for drainage of the paranasal sinuses and were evaluated for postoperative improvement of fever. RESULTS: The study sample consisted of 50 patients (74% of whom were male, mean age 48.1 years). The most frequent diagnoses at ICU admission were tetanus, pulmonary disease, and cardiovascular disease. In all, 68% of patients underwent nasogastric or enteral intubation. CT scanning most commonly showed involvement of the sphenoid sinus. In 54% of cases, sinusitis was bilateral and extended throughout the maxillary, ethmoidal, and sphenoidal sinuses. Sinusectomy was performed in all patients, and pathological secretion in the paranasal sinuses was seen in 52% of patients during surgery. Gram-negative bacteria were the most commonly isolated organisms, followed by Gram-positive bacteria and fungi. Improvement of fever was found in 82% of patients after FESS; 38% of these improved within the first 48 h post-procedure, and the remaining 62% within the first 5 postoperative days.

Retention of progenitor cell phenotype in otospheres from guinea pig and mouse cochlea.

BACKGROUND: Culturing otospheres from dissociated organ of Corti is an appropriate starting point aiming at the development of cell therapy for hair cell loss. Although guinea pigs have been widely used as an excellent experimental model for studying the biology of the inner ear, the mouse cochlea has been more suitable for yielding otospheres in vitro. The aim of this study was to compare conditions and outcomes of otosphere suspension cultures from dissociated organ of Corti of either mouse or guinea pig at postnatal day three (P3), and to evaluate the guinea pig as a potential cochlea donor for preclinical cell therapy. METHODS: Organs of Corti were surgically isolated from P3 guinea pig or mouse cochlea, dissociated and cultivated under non-adherent conditions. Cultures were maintained in serum-free DMEM:F12 medium, supplemented with epidermal growth factor (EGF) plus either basic fibroblast growth factor (bFGF) or transforming growth factor alpha (TGFα). Immunofluorescence assays were conducted for phenotype characterization. RESULTS: The TGFα group presented a number of spheres significantly higher than the bFGF group. Although mouse cultures yielded more cells per sphere than guinea pig cultures, sox2 and nestin distributed similarly in otosphere cells from both organisms. We present evidence that otospheres retain properties of inner ear progenitor cells such as self-renewal, proliferation, and differentiation into hair cells or supporting cells. CONCLUSIONS: Dissociated guinea pig cochlea produced otospheres in vitro, expressing sox2 and nestin similarly to mouse otospheres. Our data is supporting evidence for the presence of inner ear progenitor cells in the postnatal guinea pig. However, there is limited viability for these cells in neonatal guinea pig cochlea when compared to the differentiation potential observed for the mouse organ of Corti at the same developmental stage.

Partial lesions of the intratemporal segment of the facial nerve: graft versus partial reconstruction.

OBJECTIVES: In cases of partial lesions of the intratemporal segment of the facial nerve, should the surgeon perform an intraoperative partial reconstruction, or partially remove the injured segment and place a graft? We present results from partial lesion reconstruction on the intratemporal segment of the facial nerve. METHODS: A retrospective study on 42 patients who presented partial lesions on the intratemporal segment of the facial nerve was performed between 1988 and 2005. The patients were divided into 3 groups based on the procedure used: interposition of the partial graft on the injured area of the nerve (group 1; 12 patients); keeping the preserved part and performing tubulization (group 2; 8 patients); and dividing the parts of the injured nerve (proximal and distal) and placing a total graft of the sural nerve (group 3; 22 patients). RESULTS: Fracture of the temporal bone was the most frequent cause of the lesion in all groups, followed by iatrogenic causes (p < 0.005). Those who obtained results lower than or equal to III on the House-Brackmann scale were 1 (8.3%) of the patients in group 1, none (0.0%) of the patients in group 2, and 15 (68.2%) of the patients in group 3 (p <0.001). CONCLUSIONS: The best surgical technique for therapy of a partial lesion of the facial nerve is still questionable. Among these 42 patients, the best results were those from the total graft of the facial nerve.