Biomedical subjects

Mahmoud S Ali

Publications and source records attributed to Mahmoud S Ali.

4 recordsLinked to original sources

PubMed2005

Major secretory mucin expression in chronic sinusitis.

OBJECTIVE: The aim of this study was to investigate mucin expression in chronic sinusitis compared to that in normal nasal mucus. STUDY DESIGN AND SETTING: Sinus mucus samples were collected during functional endoscopic sinus surgery (FESS). The expression of 3 airway mucins, MUC2, MUC5AC, and MUC5B, was determined by ELISA. RESULTS: The 3 mucins are expressed in chronic sinusitis and in normal nasal mucus. MUC5AC and MUC5B represent a major component in sinus mucins while MUC5B and MUC2 predominated in normal nasal mucin. In sinus mucins, upregulation of MUC5AC was associated with downregulation of MUC2 and vice versa. This inverse relationship was strengthened in the presence of nasal polyps. CONCLUSION: At least 3 mucins are expressed at various levels in chronic sinusitis. An inverse relationship was identified between expression of MUC5AC and MUC2. Large prospective studies are required to unravel the complexities of sinus mucus in chronic sinusitis. SIGNIFICANCE: Mucins may be used as markers for assessment of disease severity and may also help as prognostic indicators following medical or surgical treatment.

Adolescent↗

PubMed2005

Mucin gene expression in nasal polyps.

CONCLUSIONS: A large set of mucin genes is expressed in nasal polyps. The expression pattern is complex and may reflect the wide spectrum of variables involved in polyp formation and progression. Prospective studies including subgroups of nasal polyps and involving substantial numbers of cases in each subgroup will be required to elucidate these variables and to understand how they affect mucus secretion. OBJECTIVE: At present, 15 of the 19 known mucin genes are expressed in the human airways. Nasal polyps might be expected to have a mucin expression pattern comparable to that of the airways. The aim of this study was to investigate mucin expression in nasal polyps. MATERIAL AND METHODS: Nasal polyp samples were obtained from 20 patients during functional endoscopic sinus surgery. Normal (control) sphenoid sinus mucosa was obtained from patients undergoing trans-sphenoid hypophysectomy. The expression of eight mucin genes (MUC1-4, -5AC, -5B, -6 and -7) was studied by in situ hybridization utilizing digoxigenin-labelled oligonucleotide probes. RESULTS: MUC6 and -7 were not expressed in sphenoid sinus mucosa, while all the studied mucin genes were expressed in nasal polyps. Expression patterns varied widely between individual polyps. The predominant epithelial mucin genes were MUC4, -5AC and -3, while MUC5B and -7 were mainly of glandular origin. MUC1, -2 and -6 were weakly expressed. The major alteration in gene expression in nasal polyps was found in the submucosal glands. MUC4 and -5AC represent a major component of both submucosal glands and epithelial cells in nasal polyps.

Biomarkers, Tumor↗

PubMed2002

Mixed nasal mucus as a model for sinus mucin gene expression studies.

OBJECTIVE/HYPOTHESIS: It is necessary to obtain sinus mucus from the paranasal sinus cavities to study mucin gene expression occurring in the sinuses during chronic sinusitis. This requires an invasive procedure to access the sinus cavity. There are embryological as well as histological similarities between nasal and sinus epithelia; therefore, we postulated that the mucin expression in the secreted nasal and sinus mucins might be similar. Nasal mucus, which can be obtained easily, could then replace sinus mucus in these studies. STUDY DESIGN: Sinus and nasal mucus from six patients with chronic sinusitis were analyzed in this study. METHODS: High-molecular-weight glycoproteins (mucins) were isolated and purified by sequential density gradient centrifugation in caesium chloride (CsCl). Enzyme-linked immunosorbent assay was performed to identify the antigenic identity of these mucins. RESULTS: The MUC2, MUC5AC, and MUC5B mucin genes were all expressed in the nasal and sinus mucus secretions. Antigenic studies showed an inverse relationship between MUC2 and MUC5AC expression in nasal and sinus mucus secretions. The MUC5B gene was the major mucin gene expressed in sinus mucus but not in nasal mucus. Expression of MUC2 was significantly higher in sinus mucus. Expression of MUC5AC was different between nasal and sinus mucus. CONCLUSIONS: Individual mucin expression in sinus and nasal mucus was markedly different. From this preliminary study, we conclude that nasal mucus is not a suitable substitute for sinus mucus in sinus mucin gene studies and that different pathological processes are taking place in nasal and sinus tissue in chronic sinusitis.

Chronic Disease↗

PubMed2002

Spontaneous retro- and parapharyngeal haematoma caused by intrathyroid bleed.

A case of spontaneous haemorrhage into the retropharyngeal and parapharyngeal space secondary to bleeding from a thyroid cyst is described. While many conditions are known to cause this entity, no previous papers have reported a thyroid cyst to cause such extensive haemorrhage. Haemorrhage in these spaces is of particular importance as it causes rapid airway compromise and can be life-threatening. Forty cases of non-traumatic retropharyngeal and parapharyngeal haematomas have been reported in the literature to date. Although the diagnosis can be easily established in most patients, no published review of this condition exists. This paper reviews all reports of non-traumatic retropharyngeal and parapharyngeal haematoma published in the literature to date and discusses management guidelines. We also present here for the first time the demographics and treatment results of this rare entity.

Cysts↗