Pterobothrium crassicolle parasitizing Paralichthys orbignyanus (Osteichthyes, Paralichthyidae) in Brazil.

From September 2014 to November 2015, 30 Paralichthys orbignyanus specimens were obtained from Sepetiba Bay in the municipality of Rio de Janeiro, State of Rio de Janeiro, Brazil. The fishes were necropsied and cestode larvae were recovered from the abdominal cavity, mesentery, and serosas of the stomach, intestine, spleen, liver, kidney and gonads. Nineteen fish were parasitized by a total of 90 trypanorhynch plerocerci. Based on morphological characters, these were identified as Pterobothrium crassicolle. The parasitism indices for P. crassicolle on P. orbignyanus, were 63.3% for prevalence, 4.7 for mean intensity, 3 for mean abundance and 1 to 18 for range of infection. These parasites were studied due to their importance during fish sanitary inspection, if one considers the harm that the repulsive aspect of infected fish may cause to consumers. This is the first record of P. crassicolle plerocerci parasitizing P. orbignyanus.

First record of a nematode Metastrongyloidea (Aelurostrongylus abstrusus larvae) in Achatina (Lissachatina) fulica (Mollusca, Achatinidae) in Brazil.

Achatina (Lissachatina) fulica was introduced in Brazil in the 1980s for commercial purposes ("escargot" farming) and nowadays, mainly by human activity, it is widespread in at least 23 out of 26 Brazilian states and Brasília, including the Amazonian region and natural reserves, where besides a general nuisance for people it is a pest and also a public health concern, since it is one of the natural intermediate host of Angiostrongylus cantonensis, ethiological agent of the meningoencephalitis in Asia. As Brazil is experiencing the explosive phase of the invasion, the Laboratório de Malacologia do Instituto Oswaldo Cruz/Fiocruz has been receiving samples of these molluscs for identification and search for Angiostrongylus cantonensis and Angiostrongylus costaricensis larvae. While examining samples of A. fulica different nematode larvae were obtained, including Aelurostrongylus, whose different species are parasites of felids, dogs, primates, and badger. Morphological and morphometric analyses presented herein indicated the species Aelurostrongylus abstrusus, as well as the occurrence of other nematode larvae (Strongyluris-like) found in the interior of the pallial cavity of A. fulica. This is the first report in Brazil of the development of A. abstrusus infective larvae in A. fulica evidencing the veterinary importance of this mollusc in the transmission of A. abstrusus to domestic cats. Since the spread of A. fulica is pointed out in the literature as one of the main causative spread of the meningoencephalitis caused by A. cantonensis the authors emphasize the need of sanitary vigilance of snails and rats from vulnerable areas for A. cantonensis introduction as the port side areas.

A new oxyurid genus and species from Gracilinanus agilis (Marsupialia: Didelphidae) in Brazil.

A description is provided for Gracilioxyuris agilisis n. g., n. sp. found in the cecum of Gracilinanus agilis Burmeister, 1854 (Gardner, 2005) (Didelphidae) in Brazilian Pantanal. The new species can be distinguished from Didelphoxyuris thylamisis by a dome-shaped anterior end, a weakly developed cephalic vesicle, males with no postcloacal ornamentation, and operculate eggs with 3 longitudinal ridges. Gracilioxyuris n. g. is characterized by a small and apical oral opening and double-crested lateral alae. Males possess an area rugosa as a ventral, keellike elevation with transverse striations, 4 pairs of genital papillae, the first and second pairs of which are adanal, and a third minute pair just posterior to cloacal aperture; the last pair are at the caudal end with no tail tip. Females possess a thick muscular vagina, a didelphic genital tract, and operculated eggs with ridges.

Plasmodium falciparum invasion and intraerythrocytic development are impaired by 2', 3'-dialdehyde adenosine.

Purine nucleotide synthesis in protozoa takes place exclusively via the purine salvage pathway and S-adenosyl-l-homocysteine hydrolase (SAHH) is an important enzyme in the Plasmodium salvage pathway which is not present in erythrocytes. Here, we describe the antimalarial effect of 2'3'-dialdehyde adenosine or oxidized adenosine (oADO), inhibitor of SAHH, on in vitro infection of human erythrocytes by P. falciparum. Treatment of infected erythrocytes with oADO inhibits parasite development and reinvasion of new cells. Erythrocytes pre-treated with oADO have a reduced susceptibility to invasion. Our results suggest that oADO interferes with one or more parasitic enzymes of the purine salvage pathway.