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H Gaafar

Publications and source records attributed to H Gaafar.

12 recordsLinked to original sources
PubMed1992

The effect of ammonia on the respiratory nasal mucosa of mice. A histological and histochemical study.

The effects of prolonged exposure to ammonia vapour on the histological pattern and enzymatic activity of the respiratory nasal mucosa of 75 adult male mice were investigated and compared with a control group. In the exposed animals, the nasal epithelial cells showed patches of squamous metaplasia, dysplasia, and even malignant changes in the nose of 2 animals. As regards the histochemical changes, the apical border of epithelial cells showed increased succinic dehydrogenase activity denoting increased energy production. The acid phosphatase activity was also higher, and this seemed to be a constant feature in metaplastic and neoplastic transformation. The alkaline phosphatase activity was detected only in the basal parts of epithelial and goblet cells, which was attributed to an increased activity of basal cells to form a thicker basement membrane. The periodic acid Schiff's reaction was weak in the cilia due to their partial degeneration. Prolonged exposure to ammonia interfered with the normal physiological mucociliary action resulting in accumulation of particulate matter initiating or promoting a neoplastic process.

Acid Phosphatase↗
PubMed1979

Transmission and scanning electron microscopic studies of rhinoscleroma.

Using both types of electron microscope, combined transmission and scanning electron microscopic studies were done on 6 patients with rhinoscleroma. The present work suggests the possibility of two types of organisms causing the disease: one type--being in the majority--was a rod-shaped bacillus measuring about 3 micrometers; the other type was a short, stout bacillus with terminal spiral cilia. The ultrastructure of these bacilli has been described. The advantages and limitations of each type of electron microscopy in the investigation of rhinoscleroma have been discussed.

Humans↗
PubMed1979

Electron microscopic study of previously irradiated scleroma.

Nasal biopsies from 2 scleroma patients who had received previous X-ray therapy were investigated under the electron microscope. In the lamina propria, the majority of Mikulicz cells contained numerous small vacuoles. This was attributed to the effect of X-ray therapy causing temporary suppression of the inflammatory process followed by new granuloma formation. The vacuoles of the Mikulicz cells contained some fine granular and fibrillar material of unknown origin. Rounded electron-dense bodies with microprojections on their surface were present near some Mikulicz cells. These structures were considered to be Russell bodies. Occasional small lymph vessels with obstructed lumina were seen. This might indicate the rare spread of Klebsiella rhinoscleromatis bacilli to regional lymph nodes.

Adult↗
PubMed1978

Experimental scleroma. A histopathological study.

Klebsilla rhinoscleromatis suspension was experimentally inoculated into the nose and maxillary sinus of eight adult healthy rabbits. Two normal litter-mates served as controls. The animals were killed at varying intervals up to five months following the inoculation. Histopathological examination of the upper and lower respiratory tracts revealed a consistent pulmonary peribronchial and perivascular granulomatous reaction with a Mikulic cell-like appearance. The reaction was present in all the inoculated rabbits and increased in severity as the survival period was prolonged. The significance of these findings in the aetiopathogenesis of scleroma and to scleroma in humans is discussed.

Animals↗
PubMed1977

Black hairy tongue. A scanning electron microscopic study.

A patient with tongue malignancy associated with a black hairy tongue is presented. Specimens from e area fo the black hairy tongue and from a normally appearing part were studied with the scanning electron microscope. The "hairs" consisted of elongated filiform papillae due to accumulated keratinized layers. In-between these layers, fungi and bacteria were found. The aetiology of the blck hairy tongue in this patient is discussed.

Humans↗
PubMed1977

The effect of an expectorant on the tracheal mucosa. A scanning-electron microscopic study.

The effect of an intravenous expectorant agent, i.e. Bisolvon, on the secretory activity of the tracheal mucosa of the dog was studied with the scanning electron microscope. A marked increase in the production of tracheal secretion was observed 15 and 30 min following the injection. Both the goblet cells in the epithelium and the seromucinous glands in the tunica propria contributed to the formation of the secretion. 60 min after the injection, the submucosal glands were shrunken or empty. The rapid secretory response to the expectorant, Bisolvon, confirmed the active and important role of the tracheal mucociliary clearance mechanism for the protection of the lower respiratory tract.

Animals↗
PubMed1976

Scanning electron microscopy of the endolymphatic sac epithelium.

In this study, scanning electron micrographs of the dog endolymphatic sac surface epithelium are presented. According to our morphological findings, three portions were recognized, the proximal, intermediate and distal part. The intermediate or 'rugose' portion was found the most differentiated where two types of cells were identified. These cells were seen to have many of the criteria for fluid absorption and phagocytosis. In man, alteration in the ability of these cells may lead to endolymphatic hydrops.

Animals↗
PubMed1976

Rhinoscleroma: a scanning electron-microscopic study.

Nasal biopsies from 6 patients with rhinoscleroma were studied by scanning electron microscopy. Numerous bacilli of different sizes were found on the epithelial surface. Few bacilli with thin spiral terminal cilia were seen over the surface of large protruding non-epithelial cells. These cells appeared to be the Mikulicz cells migrating from the tunica propria to the epithelial surface through small ulcerations. In the tunica propria, Mikulicz cells containing numerous bacilli were observed. In 4 patients, round bodies and long tubular structures were found on the epithelial surface. These bodies were suggested to be fungi, yet their exact nature and their relation to Klebsiella rhinoscleromatitis bacilli need further investigation.

Adult↗