Laryngotracheal manifestations of rhinoscleroma.

Rhinoscleroma is a rare, chronic granulomatous disease of infective causation. It usually begins in the nose and may progress to involve the larynx and trachea and cause dysphonia, stridor, and airway obstruction. Early rhinoscleroma is usually successfully treated with oral tetracycline, yet laryngotracheal disease may require operative intervention.

Repair of chronic tympanic membrane perforations using epidermal growth factor.

Perforation of the tympanic membrane (TM) is a frequent cause of conductive hearing loss. Persistent TM perforations often require surgical repair with an autologous tissue graft to restore hearing and prevent recurrent infection. While highly efficacious, this method of closure requires a relatively complex and expensive microsurgical procedure.

The role of guaifenesin in the treatment of sinonasal disease in patients infected with the human immunodeficiency virus (HIV).

Inflammatory sinonasal disease is a common problem in patients infected with the human immunodeficiency virus (HIV). Although some patients present with acute or chronic sinusitis, many describe persistent nasal congestion and thick, tenacious postnasal drainage, even in the absence of infection. The efficacy of guaifenesin as a mucolytic is poorly documented and support for its use in this setting is primarily anecdotal.

Changes in hyaluronan synthesis by in vitro cultured endolymphatic sac cells.

The endolymphatic sac (ELS) has been implicated in the maintenance of endolymph volume and pressure in the membranous labyrinth through fluid resorption and secretion of osmotically active substances, known as glycosaminoglycans (GAGs). To assess whether the ELS cells synthesize the GAG, hyaluronan (HA), and to further elucidate the secretory function of the ELS, a series of experiments were carried out on in vitro tissue-cultured, fetal murine ELSs. In phase 1 of the investigation, the ELSs that were attached to a small portion of the posterior labyrinth, were resected from whole otocyst specimens and studied in tissue culture.

Hyaluronan synthesis by in vitro cultured endolymphatic sac cells.

The endolymphatic sac (ELS) has been the subject of investigation for many years and yet its overall function remains unclear. It is believed mainly to be involved in the regulation of endolymph through fluid resorption and secretion of osmotically active substances. The present study was performed using in vitro cultured, fetal ELSs of 18 to 19 day gestational mice, to assess whether the ELS cells can synthesize the osmotically active polysaccharide, hyaluronan (HA).

Hyaluronan synthesis in the adult guinea pig endolymphatic sac.

The endolymphatic sac is believed to play a major role in membranous labyrinth homeostasis by controlling the volume of endolymph, removing debris, and participating in the immune response of the inner ear. The endolymphatic sac is postulated to absorb endolymph and to synthesize and secrete high-molecular-weight and osmotically active glycosaminoglycans (GAGs). The present study examines the ability of in vitro adult guinea pig endolymphatic sac cells to synthesize complex proteins and polysaccharides.

An animal model of chronic tympanic membrane perforation.

Previous investigations into the healing and reconstruction of tympanic membrane (TM) perforations have involved animal models with acute TM perforations. A problem with the acute TM perforation model is that most acute TM perforations will heal spontaneously, both in animals and human beings. A second inadequacy of acute perforation models is that they are not analogous to the salient problem in human beings: long-standing TM perforation.