[Risk of occupational exposure to hepatitis B virus in Venezuelan health workers. Multicenter study]. / Riesgo de exposición ocupacional al virus de la hepatitis B en personal de salud Venezolano. Estudio multicéntrico.

In a multicenter study, 970 serum samples were collected from venezuelan health workers. Presence of HBV serological markers (HBsAg, antiHBs and total anticore) were screened by microELISA. Two-hundred and forty-seven samples (27%) showed at least one positive marker, being the most frequently found the antisurface antibody which was present in different working areas, including those considered at the low exposure level (medicine 24.7%). The proportion of antisurface positive samples also was significantly higher in the group with more than 10 years of service compared to the prevalence showed by the group with less than 5 years (19.1 vs 12.8%). Groups considered to be at low risk, contrary to the expected results, showed a similar or higher prevalence compared to the groups classified as continues or frequent exposure (17.7 vs 8.6%). Our findings suggest a permanent HBV load circulation at the venezuelan hospitals environment.

The effect of desferrioxamine on the proliferative response of rat lymphocytes stimulated with various mitogens in vitro.

This paper reports experiments designed to evaluate the effect of desferrioxamine on lymphocytes obtained from the spleen of Sprague-Dawley rats. The results showed that desferrioxamine inhibits the proliferative response of lymphocytes stimulated by concanavalin A or pokeweed mitogen, the effect being proportional to the dose used, and being maximal at the end of the culture period. To exert its effect, desferrioxamine has to be present from the initiation of the cultures--its addition 24 h later markedly reduced its inhibitory effect. Studies of cell viability indicated that the inhibition was not due to toxicity. Lymphocytes obtained from young animals (4 to 12-week-old) were more sensitive to desferrioxamine than older animals (13 to 18-week-old). Saturation of desferrioxamine with iron abolished its effect, suggesting a direct relationship between chelating properties and inhibition, and reinforcing the hypothesis that iron plays an important role in the process of cell division.