Growth-promoting effect on iron-sulfur proteins on axenic cultures of Entamoeba dispar.

A growth-promoting factor (GPF) that promotes the growth of Entamoeba dispar under axenic culture conditions was found in fractions of mitochondria (Mt), hydrogenosomes (Hg) and chloroplasts (Cp) obtained from cells of six different protozoan, mammalian and plant species. We were able to extract the GPF from the Cp-rich leaf cells of a plant (spiderwort: Commelina communis L.) in an acetone-soluble fraction as a complex of chlorophyll with low molecular weight proteins (molecular weight [MW] approximately 4,600). We also found that on treatment with 0.6% complexes of 2-mercapthoethanol (2ME), complexes of chlorophyll-a with iron-sulphur (Fe-S) proteins (e.g., ferredoxins [Fd] from spinach and Clostridium pasteurianum) and noncomplex rubredoxin (Rd) from C. posteurianum have a growth-promoting effect on E. dispar. These findings suggest that E. dispar may lack a sufficient quantity of some essential components of Fe-S proteins, such as Fe-S center.

Kimura's disease.

Kimura's disease is a rare condition of unknown aetiology. It usually presents as a mass in the head and neck region. The diagnosis is confirmed by biopsy and usually treated by excision even though recurrence is common. This condition can be mistaken for a malignant tumour. In this case report Kimura's disease presented as a non-specific lymphadenitis in an Arab patient.

Osteoma of the ear canal presenting with headache.

Osteoma of external auditory canal is a rare benign tumour. Usually it is found incidentally and often symptomless. Here we have a case of osteoma arising from the anterior wall of the bony external auditory canal, causing ipsilateral temporal headache which was relieved by removal of tumour.