Biomedical subjects

L Santamaria

Publications and source records attributed to L Santamaria.

58 records · Page 4Linked to original sources

PubMedDate not supplied

Multinucleate epithelial cells in the ductuli efferentes of human epididymis.

The histological and ultrastructural study of the ductuli efferentes in epididymides from 40 adult men revealed the occurrence of multinucleate epithelial cells in all specimens. These cells appeared in the luminal protrusions of epithelial folds and correspond to either principal or ciliated cells. The ultrastructure of their cytoplasm did not differ from that of their respective mononucleate cells. Multinucleate cells contained 3-20 closely juxtaposed nuclei, thus appearing much more irregularly outlined than those of the mononucleate epithelial cells. Multinucleation four times more frequent in the principal cells than in the ciliated cells. The number of multinucleate cells increased progressively from the age of 60 years onwards. The average number of nuclei per cell increased in the fourth decade of life, was maintained up to the eighth decade, and then increased again.

Adolescent↗

PubMedDate not supplied

[Variations in the enzymatic activity in the calf muscle of the rat following ischemia].

Muscle lesions induced by ischaemia have been investigated in depth from the morphological standpoint, though the metabolic changes thus caused are still the subjects of discussion. Measurements were therefore made of enzyme activities in rat calf muscle, and their changes following incomplete ischaemia. Three enzymes were studied: CPK (typical of muscle metabolism), G-6-PDH (pentose cycle, indicator of the extent of repair processes), and uptake of a labelled amino acid (L-leucine, on the part of tissue proteins. An initial increase in activity and uptake was followed by recovery functions, due to installation of a collateral circulation. This appeared to be complete by the 5th day.

Animals↗

PubMedDate not supplied

[Modifications of the enzymatic activity in the calf muscle of the rat in circulatory stasis].

In the attempt to identify enzymatic variations in the sural muscle of rats as a result of arterial ischaemia, the enzymatic variations of LDH, PHI, MDH, GOT, G-6-PDH and CPK were measured in a sural muscle in which both arterial ischaemia and venous stasis were induced. From the results examined it may be concluded that both techniques produce reversible lesions and that there is no significant difference in enzymatic activity between the two experimental conditions.

Animals↗

PubMedDate not supplied

Carotenoids reduce the chromosomal damage induced by bleomycin in human cultured lymphocytes.

The supplementation with beta-carotene and canthaxanthin, two carotenoids with and without pro-vitamin A activity, reduced in vitro the number of micronuclei induced in human cultured lymphocytes by the chemotherapeutic radiomimetic drug bleomycin. The genotoxic activity of this substance is supposed to be mediated by a free radical mechanism. The reduction of micronucleated cells was in correlation with donors' carotenoid blood levels. It has been observed that 20 weeks are needed, following the end of carotenoid supplementation, in order to return to the high levels of micronuclei induced by bleomycin. It is suggested that this protective effect is due to the antioxidant properties of carotenoids acting against free radical-mediated genotoxic damage.

Administration, Oral↗