Glutamine aminotransferase and glutamine aminohydrolase ratio as a possible test for antitumour compounds.

Three known antitumour drugs have been tested for their effect on the GAT/GNase ratio of Ehrlich Ascites cells and host plasma. It was observed that all these drugs had changed the ratio of the 2 types of glutaminases from below 1.0 to the normal value of 1.0, this was accompanied with an increase in the survival time of the tumour-bearing animals. There was, however, no effect on the plasma GAT/GNase ratio of normal animals in the presence of the 3 antitumour compounds tested.     

The sensitivity to plasmin digestion of human IgG proteins of different heavy chain subclasses.

Normal IgG and purified IgG proteins of all 4 subclasses were digested with plasmin. As expected, IgG3 proteins were highly susceptible to degradation. Usually, activation with streptokinase resulted in faster and more accentuated degradation, but normal IgG was more intensely degraded by nonactivated plasmin. The presence of plasmin activators in IgG preparation might account for this observation.     

Interaction of extrinsic fluorescent probes with E. coli glutamine synthetase.

Binding of 2-p-toluidinylnaphthalene-6-sulfonate (TNS) to adenylylated (E--11) glutamine synthetase is cooperative and time-dependent, with 3 dye sites per subunit. In fluorescence polarization experiments TNS and pyrene butyrate give normalized Perrin plots that indicate a symmetrical arrangement of dye excited state dipoles, relative to the rotational axis of the oblate ellipsoid of the dodecameric native enzyme.     

Immunological sensitization following inapparent infection with dengue virus type 3 in rhesus monkeys.

Rhesus monkeys previously given dengue virus type 3, without apparent viremia or antibody response, exhibited a secondary-type response upon reinoculation. These data suggest that monkeys can be immunologically sensitized to dengue virus without detectable antibody production.