For a long time, superoxide generation by an NADPH oxidase was considered as an oddity only found in professional phagocytes. Over the last years, six homologs of the cytochrome subunit of the phag...

/pdf/the-nox-family-of-ros-generating-nadph-oxidases-physiology-zjc88zvh59.pdf

The NOX Family of ROS-Generating NADPH Oxidases: Physiology and Pathophysiology

ObjectiveThis update of a 2004 guideline codeveloped by the American Academy of Otolaryngology—Head and Neck Surgery Foundation, the American Academy of Pediatrics, and the American Academy of Family Physicians, provides evidence-based recommendations to manage otitis media with effusion (OME), defined as the presence of fluid in the middle ear without signs or symptoms of acute ear infection. Changes from the prior guideline include consumer advocates added to the update group, evidence from 4 new clinical practice guidelines, 20 new systematic reviews, and 49 randomized control trials, enhanced emphasis on patient education and shared decision making, a new algorithm to clarify action statement relationships, and new and expanded recommendations for the diagnosis and management of OME.PurposeThe purpose of this multidisciplinary guideline is to identify quality improvement opportunities in managing OME and to create explicit and actionable recommendations to implement these opportunities in clinical pra...

https://journals.sagepub.com/doi/pdf/10.1177/0194599815623467

Clinical Practice Guideline Otitis Media with Effusion (Update)

THE POSITION STATEMENT The Joint Committee on Infant Hearing (JCIH) endorses early detection of and intervention for infants with hearing loss. The goal of early hearing detection and intervention (EHDI) is to maximize linguistic competence and literacy development for children who are deaf or hard of hearing. Without appropriate opportunities to learn language, these children will fall behind their hearing peers in communication, cognition, reading, and social-emotional development. Such delays may result in lower educational and employment levels in adulthood.1 To maximize the outcome for infants who are deaf or hard of hearing, the hearing of all infants should be screened at no later than 1 month of age. Those who do not pass screening should have a comprehensive audiological evaluation at no later than 3 months of age. Infants with confirmed hearing loss should receive appropriate intervention at no later than 6 months of age from health care and education professionals with expertise in hearing loss and deafness in infants and young children. Regardless of previous hearing-screening outcomes, all infants with or without risk factors should receive ongoing surveillance of communicative development beginning at 2 months of age during well-child visits in the medical home.2 EHDI systems should guarantee seamless transitions for infants and their families through this process.

/pdf/year-2007-position-statement-principles-and-guidelines-for-1m07julcke.pdf

Year 2007 position statement: Principles and guidelines for early hearing detection and intervention programs

Objective. The primary purpose of this study was to examine the relationship between age of enrollment in intervention and language outcomes at 5 years of age in a group of deaf and hard-of-hearing children. Method. Vocabulary skills at 5 years of age were examined in a group of 112 children with hearing loss who were enrolled at various ages in a comprehensive intervention program. Verbal reasoning skills were explored in a subgroup of 80 of these children. Participants were evaluated using the Peabody Picture Vocabulary Test and a criterion-referenced measure, the Preschool Language Assessment Instrument, administered individually by professionals skilled in assessing children with hearing loss. A rating scale was developed to characterize the level of family involvement in the intervention program for children in the study. Results. A statistically significant negative correlation was found between age of enrollment and language outcomes at 5 years of age. Children who were enrolled earliest (eg, by 11 months of age) demonstrated significantly better vocabulary and verbal reasoning skills at 5 years of age than did later-enrolled children. Regardless of degree of hearing loss, early-enrolled children achieved scores on these measures that approximated those of their hearing peers. In an attempt to understand the relationships among performance and factors, such as age of enrollment, family involvement, degree of hearing loss, and nonverbal intelligence, multiple regression models were applied to the data. The analyses revealed that only 2 of these factors explained a significant amount of the variance in language scores obtained at 5 years of age: family involvement and age of enrollment. Surprisingly, family involvement explained the most variance after controlling for the influence of the other factors ( r = .615; F change = 58.70), underscoring the importance of this variable. Age of enrollment also contributed significantly to explained variance after accounting for the other variables in the regression ( r = −.452; F change = 19.24). Importantly, there were interactions between the factors of family involvement and age of enrollment that influenced outcomes. Early enrollment was of benefit to children across all levels of family involvement. However, the most successful children in this study were those with high levels of family involvement who were enrolled early in intervention services. Late-identified children whose families were described as limited or average in involvement scored >2 standard deviations below their hearing peers at 5 years of age. Even in the best of circumstances (eg, early enrollment paired with high levels of family involvement), the children in this study scored within the low average range in abstract verbal reasoning compared with hearing peers, reflecting qualitative language differences in these groups of children. Conclusions. Consistent with the findings of Yoshinaga-Itano et al, 1 significantly better language scores were associated with early enrollment in intervention. High levels of family involvement correlated with positive language outcomes, and, conversely, limited family involvement was associated with significant child language delays at 5 years of age, especially when enrollment in intervention was late. The results suggest that success is achieved when early identification is paired with early interventions that actively involve families.

Early Intervention and Language Development in Children Who Are Deaf and Hard of Hearing

AVERAGING, when used to extract extremely small signals from relatively high levels of background noise, allows detection of evoked potentials at surprisingly large distances from the site of neuronal activity. In animals, volume-conducted potentials from brain-stem auditory structures can be recorded throughout the brain (Grinnell, 1963; Bullock et ah, 1968; Jewett, 1970) and even from the scalp (Jewett, 1970). In humans, auditory-evoked potentials can be detected at the vertex due to neural activity from subcortical structures (Jewett, Romano and Williston, 1970) as well as from primary cortical areas (Vaughan and Ritter, 1970). Under the conditions of skull and scalp boundaries and intracranial inhomogeneities, recordings from a single electrode position offer little indication as to the location of a wave's neural generator(s), whereas multiple recording sites may be more informative.

Auditory-evoked far fields averaged from the scalp of humans

Development of the inner ear of the mouse: a radioautographic study of terminal mitoses.

Early identification of hearing impairment in infants and young children

Objectives: To determine the economic effect on the US economy of the cost of caring for people with communication disorders as well as the cost of lost or degraded employment opportunities for people with such disorders, including disorders of hearing, voice, speech, and language.



Study Design: Survey of available historical and contemporary governmental and scholarly data concerning work force distribution and the epidemiology of disorders of hearing, voice, speech, and language.



Method: Analysis of epidemiological and economic data for industrialized countries, North America, and the United States.



Results: Communication disorders are estimated to have a prevalence of 5% to 10%. People with communication disorders may be more economically disadvantaged than those with less severe disabilities. The data suggest that people with severe speech disabilities are more often found to be unemployed or in a lower economic class than people with hearing loss or other disabilities. Communication disorders may cost the United States from $154 billion to $186 billion per year, which is equal to 2.5% to 3% of the Gross National Product.



Conclusions: Communication disorders reduce the economic output of the United States, whose economy has become dependent on communication-based employment. This trend will increase during the next century. The economic cost and the prevalence rates of communication disorders in the United States indicate that they will be a major public health challenge for the 21st century.

https://onlinelibrary.wiley.com/doi/pdf/10.1097/00005537-200002010-00010

Redefining the survival of the fittest: communication disorders in the 21st century.

Hypothesis: Cisplatin causes the generation of reactive oxygen species (ROS), which interferes with the antioxidant defense system of Corti's organ and results in damage to the hair cells. Background: Cisplatin is a widely used chemotherapeutic agent with the dose-limiting side effect of ototoxicity. Evidence is accumulating that cisplatin interferes with the antioxidant defense system of Corti's organ. Methods: Organotypic explants of P-3 rat organ of Corti were the in vitro model system. Presence of intact auditory hair cells and stereocilia bundle integrity was assayed by phalloidin-FITC staining. Fluorescent dye probes detected H 2 O 2 and intracellular thiol [e.g., glutathione (GSH)]. Spectrophotometric analysis determined antioxidant enzyme levels. Results: There was a rapid dose-dependent cisplatin cytotoxicity in the explants after 48 h of exposure. An accumulation of H 2 O 2 and a reduction of GSH levels were observed within cisplatin-exposed hair cells. L-buthionine sulfoximine, an inhibitor of GSH formation, enhanced cisplatin ototoxicity, whereas N 6 -(2-phenylisopropyl) adenosine, an adenosine agonist, elevated antioxidant enzyme levels and ameliorated cisplatin toxicity. The following molecules protected hair cells from cisplatin-induced damage: GSH; glutathione diethyl ester (GSHe); ebselen (EBS); 4-methylthiobenzoic acid (MTBA); and D-methionine (D-MET). EBS, MTBA, and D-MET in vitro protection correlates with in vivo protection in rats. Conclusions: Organotypic culture of Corti's organ has been validated as a model for studying cisplatin toxicity and for screening otoprotective molecules. Some of the events that contribute to cisplatin's ability to damage auditory hair cells are generation of ROS (e.g., H 2 O 2 ), depletion of intracellular GSH, and interference with antioxidant enzymes within the cochlea. Agents that bolster the cochlea's antioxidant system can prevent cisplatin destruction of auditory hair cells. Identified protective agents may prove to be clinically useful in limiting or completely protecting from cisplatin ototoxicity.

Use of Organotypic cultures of Corti's organ to study the protective effects of antioxidant molecules on cisplatin-induced damage of auditory hair cells

In the mouse, cochlear potentials appeared first with narrow ranges on the eighth day after birth and gradually increased by the fourteenth day when the responses attained adult values. Nerve action potentials as recorded from the round window appeared on the ninth day when cochlear potential ranges extended from 0.6 to 8 kc. R1 R2 as recorded from the eighth nerve appeared one day after the N1 N2 is recorded from the round window membrane. The Preyer responses appeared when action potentials could be recorded from the eighth nerve. The development anatomical changes in the mouse are similar to those found in the albino rat. The structures in the cochlea are present at birth and then there is gradual maturation of the organ of Corti, reachiag adult size by the eighth to tenth day. The mature configuration of the cochlea by the tenth day correlates with the behavioral and physiological findings.

Robert J. Ruben

Papers

Development of the inner ear of the mouse: a radioautographic study of terminal mitoses.

Early identification of hearing impairment in infants and young children

Redefining the survival of the fittest: communication disorders in the 21st century.

Use of Organotypic cultures of Corti's organ to study the protective effects of antioxidant molecules on cisplatin-induced damage of auditory hair cells

Development of Hearing in the Normal Cba-J Mouse: Correlation of Physiological Observations with Behavioral Responses and with Cochlear Anatomy