Ultrastructural study of taste buds at rest and after stimulation, and comparative study between type III cell and Merkel cells

Changes in the pore region of the cell membrane have been studied in order to learn if this region plays an active part in the preneural phase of taste. We have observed, though not consistently, that the pore size is variable and that their contents are not constantly amorphous or homogeneous. The results are not so significant, however, as to allow of the formulation of any firm conclusions. The similarity between type III cells and Merkel cells (cells of the tactile system) was surprising. The probable role of the type III cell in taste is discussed.

Sugar as a vehicle for iron fortification

Sugar as a vehicle for iron fortification presents several advantages over the other vehicles used in the last three decades. In vitro studies demonstrated that ferrous sulfate added to sugar in proportion of 1 mg to 1 g, respectively, is maintained in the ferrous form for a period of at least 1 year and does not induce adverse changes in the vehicle. Sugar, by itself, carries practically no inhibitors for the absorption of iron. Iron absorption from fortified sugar mixed with vegetals is the same as that of native vegetal iron. The absorption from fortified sugar is increased more than 50% over that observed from native vegetal when it is administered as a drink during the ingestion of a meal. A further increase in absorption was found when fortified sugar was administered with beverages. The mean absorption ratio of fortified sugar given with orange juice, Coca-Cola, and Pepsi-Cola to a reference dose of iron ascorbate was between 0.45 and 0.66, which is more than 3 times the absorption of this iron fortification mixed with vegetals. The mean absorption ratio from coffee was 0.30, and from coffee with milk, 0.15. These data indicate that the fortification of sugar with iron could be a better procedure for the prevention of iron deficiency than the iron fortification of bread and wheat products, from which iron is poorly absorbed. It could be used in developing countries where beverages are highly consumed by the low socioeconomic class. This program could be extended to all sugar consumption or be restricted to soft drinks.

The cell-free synthesis of cytochrome c by a microsomal fraction from rat liver

Conditions were investigated for demonstrating the synthesis in vitro of the complete molecule of cytochrome c by isolated liver microsomal systems from partially hepatectomized rats. It was first found that in vivo the early labelled cytochrome c associated with the microsomal fraction required, by comparison with the mitochondrial pool, more drastic conditions of extraction and its binding was less affected by freezing and thawing of the subcellular particles. The procedure of extraction and purification of cytochrome c had to be modified accordingly, to assure the recovery of the recently synthesized molecule. Several subcellular fractions were isolated from regenerating liver with a homogenization medium containing either 5 or 10mm-Mg(2+) and most of them were active in the synthesis of the cytochrome c apoprotein. The microsomal fraction, in the presence of either cell sap or pH5.0 fraction, was also able to incorporate [(59)Fe]haemin, delta-amino[(3)H]laevulic acid and (55)Fe into the prosthetic group of cytochrome c. These experiments confirm firmly the conclusions of our previous results obtained in vivo showing that both the apoprotein and the haem moieties are made and linked together on cytoplasmic ribosomes and only then is the complete molecule transferred to the mitochondria.

Foot granular cell myoblastoma

Granular cell myoblastoma is a benign tumor of undetermined origin. It is rarely diagnosed clinically and frequently discovered only as an incidental finding on physical examination. The authors present a 5-year follow-up review of a foot granular cell myoblastoma treated by local excision. A review of the literature is included. To the authors' knowledge this is only the second such case reported.