Cryptofolione derivatives from Cryptocarya alba fruits.

Cryptofolione (1) and the new cryptofolione derivative 6-(4,6-dimethoxy-8-phenyl-octa-1,7-dienyl)-4-hydroxy-tetrahydro-pyran-2-one (2) were isolated from the fruits of Cryptocarya alba. The structures were elucidated by spectroscopic methods. Cryptofolione showed activity towards Trypanosoma cruzi trypomastigotes, reducing their number by 77% at 250 microg mL(-1). Cryptofolione showed moderate cytotoxicity in both macrophages and T. cruzi amastigotes. It also displayed a mild inhibitory effect on the promastigote form of Leishmania spp. As both cytotoxic and trypanocidal effects are similar, the compound presented little selectivity in our assay models.

Leishmanicidal activity of combretastatin analogues and heteroanalogues.

We have investigated the in vitro leishmanicidal activity of representative members from series II-V of combretastatin analogues and heteroanalogues. Most of them exhibited different degrees of activity against various strains of Leishmania spp. The diaryl(heteroaryl)ethane system or the more complex fused heterocyclic stilbenoids, constitute useful skeletal bases to support some kind of antiparasitic activity. Particularly, the incorporation of 2-furyl substituents led to potent antileishmanial compounds, which have been selected for in vivo testing on murine models.

Nematodes of armadillos in Paraguay: a description of a new species Aspidodera esperanzae (Nematoda: Aspidoderidae).

Twelve species of nematodes comprising 9 genera were recovered from the gastrointestinal tract of 2 Euphractus sexcinctus and 2 Dasypus novemcinctus captured in the Department of San Pedro, Paraguay. All armadillos were infected with 1 or more species of nematode. The following nematodes were recovered: Mazzia mazzia, Spirura guianensis, Trichohelix tuberculata, Ancylostoma sp., Moennigia complexus, Moennigia pintoi, Ascaris dasypodina, Cruzia tentaculata, Aspidodera fasciata, Aspidodera scoleciformis, Aspidodera esperanzae n. sp., and Heterakinae gen. sp. This report describes a new species of the Aspidodera nematode, Aspidodera esperanzae n. sp., the first species to be reported bearing cephalic cordons made up of 7 longitudinal loops in the subfamily of Aspidoderinae. This study also documents a new host record for S. guianensis and shows a new geographical distribution in Paraguay for M. mazzia, S. guianensis, T. tuberculata, M. complexus, and M. pintoi.

Animal reservoirs for Trypanosoma cruzi infection in an endemic area in Paraguay.

Animal reservoirs for Trypanosoma cruzi infection were investigated in 5 communities in the Department of San Pedro, currently one of Paraguay's most highly endemic areas. A total of 112 domestic animals (37 cattle, 2 horses, 1 ass, 20 pigs, 44 dogs and 8 cats) and 4 wild animals (1 white-eared opossum, 2 yellow armadillos and 1 common long-nosed armadillo) were examined for blood. Although no trypomastigotes were found by 2 direct observation methods, the microhaematocrit and Giemsa stained thick and thin smears methods, several forms of trypanosoma flagellates morphologically identical to T. cruzi were detected in the liver infusion tryptose (LIT) medium from a single sample taken from a yellow armadillo, Euphractus sexicintus. When serum samples of all the animals were examined for antibody to T. cruzi by direct agglutination (DA) test, 3 cattle, 2 pigs, 16 dogs and 3 cats had positive titers (1:32 or greater), but no wild animals showed positive reactions. T. cruzi was not found by culture nor microscopic examination of samples from any of the seropositive animals. However, domestic animals such as cattle, pigs, dogs and cats which were found to be seropositive in this study, possibly act as an animal reservoir in this endemic area as well as armadillos in which T. cruzi was observed.