Immunoassay with recombinant Trypanosoma cruzi antigens potentially useful for screening donated blood and diagnosing Chagas disease.

A new enzyme immunoassay (EIA), the Dia Kit Bio-Chagas assay (Gador S.A.), is potentially useful for detecting antibodies to Trypanosoma cruzi in the diagnosis of infected individuals and the screening of blood in blood banks.

Adenylate cyclase activity in cyanobacteria: activation by Ca(2+)-calmodulin and a calmodulin-like activity.

An adenylate cyclase activity was partially characterized in the cyanobacterium Anabaena sp. The enzyme activity is found in soluble cell fractions and shows an apparent molecular weight of about 183,400. This adenylate cyclase is activated by Ca2+ and bovine brain or spinach calmodulin and it is inhibited by EGTA and some phenothiazine derivatives.

Toxoplasma gondii: a rapid method for the isolation of pure tachyzoites. Preliminary characterization of its genome.

A rapid and simple technique for the purification of Toxoplasma gondii tachyzoites was developed. Highly purified parasites were obtained from the peritoneal exudates of infected mice by means of two consecutive discontinuous sucrose gradients run at low speed (10,000xg, 30 min). Parasites obtained by this method conserved its biological activity.