RESUMO
1. A diphasic medium of simple preparation is described for the indefinite cultivation of T. rhodesiense and T. gambiense. 2. The chief advantage of the medium is that it contains rabbit blood and thus obviates the necessity of using human blood. 3. The flagellates develop only to the proventricular stage; hence the cultures are noninfective. 4. The proventricular forms of both T. rhodesiense and T. gambiense consume sugar with the concomitant formation of acid. They are aerobic fermenters. 5. Very little, if any, ammonia is produced by the living parasites.
Assuntos
Meios de Cultura/história , Trypanosoma brucei gambiense/crescimento & desenvolvimento , Trypanosoma brucei rhodesiense/crescimento & desenvolvimento , Animais , Sangue/parasitologia , Meios de Cultura/metabolismo , História do Século XX , HumanosRESUMO
Larval Taenia taeniaeformis in vivo accumulates 45Ca2+ in soft tissues and calcareous corpuscles. Radioactivity was demonstrable in the corpuscles six months after a single dose of 45Ca2+ was administered to the host by means of a stomach tube. Ca2+ also was taken up by isolated larvae. Accumulation in vitro was more rapid then in vivo and was correlated with the external Ca2+ concentration. Temperature variation, oxygen availability, and metabolic inhibitors had little effect on the Ca2+ uptake, indicating that active transport of Ca2+ is unlikely in this parasite. Variations in the external Pi concentrations had no effect on Ca2+ accumulation or on its distribution. Addition of 5% CO2 increased the uptake of Ca2+ by the calcareous corpuscles under anaerobic conditions. Radioactivity from NaH14CO3 also was accumulated in soft tissues and corpuscles of T. taeniaeformis. Assuming that the 14C taken up by the corpuscles was in the form of 14CO3(2-), the ratio of Ca2+ to CO3(2-) accumulation in the corpuscles approximates the ratio of these constituents in dolomite: CaMg(CO3)2.
