Three compounds of an aminothiol family of iron chelators were examined for activity against trypomastigote (human) and epimastigote (vector) forms of Trypanosoma cruzi: tetraethyl and tetramethyl derivatives of ethane-1,2-bis (N-1-amino-3-ethyl butyl-3-thiol) (BAT-TE and BAT-TM) and N',N',N'-tris-(2-methyl-2-mercaptopriopyl)- 1,4,7-triazacyclonane (TAT). BAT-TE at 270 microM completely arrested the growth of trypomastigote forms in mouse blood stored at 4 degrees C for 24 h (IC(50) 67.7+/-7 microM), while BAT-TM arrested growth at 630 microM (IC(50) 158+/-17 microM) and TAT at concentrations >800 microM (IC(50) 415+/-55 microM). In T. cruzi-infected mice, BAT-TE and BAT-TM had no anti-trypanosomal activity in doses up to 200 mg/kg, whether the route of administration was intraperitoneal or oral, and TAT was not tested due to insufficient quantity. TAT had an IC(50) of 52+/-7 microM against the epimastigote forms while BAT-TM and BAT-TE were inhibitory only at concentrations >250 microM. The trypanocidal activity of BAT derivatives in blood stored at 4 degrees C makes these compounds potential candidates for the purpose of clearing donated blood of trypomastigotes.
The activity of jatrogrossidione, the main diterpene of Jatropha grossidentata and jatrophone from Jatropha isabellii was determined against Leishmania and Trypanosoma cruzi strains in vitro as well as against Leishmania amazonensis in vivo. Jatrogrossidione showed a strong in vitro leishmanicidal and trypanocidal activity with IC100 of 0.75 and 1.5–5.0 μg/mL, respectively. Under similar conditions, the IC100 of glucantime, ketoconazole and pentamidine towards Leishmania strains were >100, 50–100 and 1 μg/mL, respectively. The IC50 of jatrogrossidione was <0.25 μg/mL against amastigote forms of Leishmania infecting macrophages, with toxicity at concentrations higher than 0.5 μg/mL. BALB/c mice infected with L. amazonensis strain PH 8 were treated 24 h after infection with jatrogrossidione and jatrophone for 13 consecutive days. Jatrophone at 25 mg/kg/day subcutaneously administered was significantly active (p<0.05) against the virulent strain PH 8 of L. amazonesis; it was more active than Glucantime at 112 mg Sbv per kg/day. Subcutaneous administration of jatrophone, however, proved to be too toxic under our assay conditions. Assays of single local treatment on the footpad infection 2 weeks after inoculation of L. amazonensis indicated that jatrogrossidione and jatrophone were inactive at the selected doses.
A total of 122 apparently healthy Bolivian Aymara-mixed children ranging in age from 2 to 12 years were tested for lactose absorption using the standard lactose tolerance test with blood glucose determination. Analysing the sample according to the age of the probands, we found an increased age related frequency of lactose malabsorption showing final percentages of 55% in the 2 to 5 years group, 57.4% in the 6 to 10 years group, and 77.4% in the 11 to 15 years group.