More than one disease process in chronic sinusitis based on mucin fragmentation patterns and amino Acid analysis.

Objective. To characterise fragmentation patterns and amino acid composition of MUC2 and MUC5AC in chronic sinusitis. Methods. Antigenic identity of purified sinus mucins was determined by ELISA. Fragmentation patterns of a MUC5AC rich sample mucin were analysed by Sepharose CL-2B gel chromatography. Samples, divided into one MUC2 rich and one MUC5AC rich group, were subjected to sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and their amino acid contents were analysed. Results. Reduction, trypsin digestion, and papain digestion produced progressively smaller mucin species. On SDS-PAGE, digested MUC5AC rich mucin produced four distinct products. Amino acid analysis was characteristic of mucins with high serine, threonine, and proline contents and reduction and proteolysis increased relative proportions of these amino acids. MUC5AC rich mucins contained more protein than MUC2 rich mucins. Conclusion. Sinus mucin fragmentation produced mucin subunits and glycopeptide units of smaller molecular sizes which are likely to have lower viscoelastic properties. Applying this in vivo could alter mucus physical properties and biologic functions. Amino acid contents of MUC2 and MUC5AC mucins are different. This could be contributing to biological properties and functions of sinus mucins. These data suggest that there may be different pathological processes occurring at the cellular level on chronic sinusitis.

Mucin gene expression in reflux laryngeal mucosa: histological and in situ hybridization observations.

Objectives/Hypothesis. To determine if laryngopharyngeal reflux alters mucin gene expression in laryngeal mucosa. Methods. In situ hybridization was employed to study the expression of the 8 well-characterised mucin genes MUC1-4, 5AC, 5B, 6, and 7 in reflux laryngeal mucosa from laryngeal ventricles, posterior commissures, and vocal folds compared to control/normal laryngeal mucosa. Results. MUC1-5 genes are expressed in normal and reflux laryngeal mucosa. MUC1, 3 and 4 are expressed in respiratory and squamous mucosa whereas MUC2 and 5AC are expressed in respiratory mucosa only. MUC3, 4 and 5AC are downregulated in reflux mucosa. MUC5AC expression is significantly reduced in the 3 mucosal sites and when mucosal type was taken into account, this remains significant in combined laryngeal and ventricular mucosa only. Conclusions. MUC3, 4 and 5AC expression is downregulated in laryngopharyngeal reflux. This may be due to laryngeal mucosal metaplasia and/or alteration of mucin gene expression in the preexisting mucosa. Altered mucin gene expression might predispose laryngeal mucosa to the damaging effect of reflux.

Nasosinus mucin expression in normal and inflammatory conditions.

PURPOSE OF REVIEW: Mucin expression in normal nasosinus mucosa is upregulated in inflammatory conditions. However, as the first nine mucin genes are expressed, and as more mucins are expected to be expressed in nasosinus mucosa, the range and pattern of variations in mucin expression in nasosinus mucosa would be wide and complicated. This review discusses current knowledge on mucin expression in normal and pathologic nasosinus mucosa. RECENT FINDINGS: Studies on nasosinus mucin expression indicate that mucin genes upregulated in inflamed nasosinus mucosa include MUCs1, 2, 4, 5AC, 5B and 8 in different combinations and to various degrees. Nasosinus submucosal glands play a more important role in mucin expression than surface epithelium. However, most of the studies on nasosinus mucin expression are focused on basic science and as yet the clinical implications of nasosinus mucin gene expression are still unclear. SUMMARY: Nasosinus mucin expression is very complicated. Studies including large numbers of samples are needed to investigate the role of different physiological and pathological variables, including inflammatory mediators, in the control of nasosinus mucin expression. This is essential for better understanding of clinical implications of altered nasosinus mucin expression and for future therapeutic applications.

Laryngopharyngeal reflux: diagnosis and treatment of a controversial disease.

PURPOSE OF REVIEW: Laryngopharyngeal reflux is a well-recognized and widely used term in ear, nose and throat practice. However, the symptoms and signs attributed to laryngopharyngeal reflux are non-specific and treatment is usually empirical. This review discusses current knowledge on diagnosis and treatment of laryngopharyngeal reflux. RECENT FINDINGS: Information is evolving regarding the implications of laryngopharyngeal reflux in the development of pathological conditions affecting the upper aerodigestive tract epithelium such as chronic laryngitis, otitis media with effusion and chronic sinusitis. However, there is still much to learn about the pathophysiologic mechanisms of laryngopharyngeal reflux and their role in its related disease conditions and there is still considerable controversy on diagnostic as well as therapeutic parameters for this condition. There is no consensus on the diagnosis and treatment of laryngopharyngeal reflux and the majority of clinicians depend mainly on clinical findings and empirical therapeutic tests rather than more specific investigations. SUMMARY: The concept of laryngopharyngeal reflux is still controversial. The current practice of empirical treatment with proton-pump inhibitors is based on weak evidence. However, this practice seems to be widely accepted and will not change until further clinical and laboratory studies improve our understanding of this common and well-recognized condition.

Microscopic transtracheal repair of migrating tracheoesophageal fistula.

OBJECTIVE: The repair of a persistently leaking migrating tracheoesophageal fistula (TEF) represents a particular challenge owing to the low site of the fistula down to the tracheoesophageal septum (TES). A simple microscopic approach to repair a migrating TEF is described. DESIGN: A description of five cases of migrating TEF. The repair technique and surgical outcome are described in detail. SETTING: Tertiary care referral hospital. METHODS: Excision of the fistula tract was done under local anesthesia and microscopic vision using microlaryngoscopic instruments followed by one-layer repair without soft tissue interposition. This technique was used in one patient with a leaking migrating TEF when planned dissection through the TES was abandoned. Subsequently, the technique was employed in four other patients with a similar TEF. MAIN OUTCOME MEASURES: Evidence of complete closure of the fistula was assessed clinically 1 week postoperatively. This was followed by methylene blue and Gastrografin swallowing tests. The methylene blue test was repeated after 6 months to exclude recurrence of the fistula and confirm persistent closure. RESULT: Complete closure of the fistulae was achieved when assessed clinically and by methylene blue and Gastrografin tests. All patients were discharged on a normal diet. Stable closure was confirmed by the methylene blue test after 6 months. The microlaryngoscopic instruments and surgical microscope have greatly facilitated access and dissection of the migrating fistula with minimum soft tissue loss. CONCLUSION: The described technique is simple, relatively safe, and reproducible for closure of a small migrating TEF. It can also be used to repair small, nonmigrating TEF.