Seroprevalence and risk factors associated with T. gondii infection in pregnant individuals from a Brazilian Amazon municipality.

The aim of this study was to determine the prevalence and to identify the risk factors associated with T. gondii infection in pregnant individuals living in the Ponta de Pedras municipality, Marajó Archipelago, State of Pará, where an outbreak of toxoplasmosis occurred in 2013. From 2014 to March 2017, a cross-sectional study was conducted, including 555 pregnant individuals aged 13- to 42-years-old. Serological tests (enzyme immunoassays) were performed, and socioenvironmental and behavioral information were obtained through the application of a questionnaire. A prevalence of 68.3% was detected, and older age, having contact with soil and living in an urban area were the risk factors associated with seropositivity. The study confirmed the high prevalence of infection among pregnant individuals in the region. The association of the infection with the variables of residential area and contact with soil indicates that there was environmental contamination by T. gondii oocysts in the municipality.

Histidine-rich protein 2 (pfhrp2) and pfhrp3 gene deletions in Plasmodium falciparum isolates from select sites in Brazil and Bolivia.

More than 80% of available malaria rapid diagnostic tests (RDTs) are based on the detection of histidine-rich protein-2 (PfHRP2) for diagnosis of Plasmodium falciparum malaria. Recent studies have shown the genes that code for this protein and its paralog, histidine-rich protein-3 (PfHRP3), are absent in parasites from the Peruvian Amazon Basin. Lack of PfHRP2 protein through deletion of the pfhrp2 gene leads to false-negative RDT results for P. falciparum. We have evaluated the extent of pfhrp2 and pfhrp3 gene deletions in a convenience sample of 198 isolates from six sites in three states across the Brazilian Amazon Basin (Acre, Rondonia and Para) and 25 isolates from two sites in Bolivia collected at different times between 2010 and 2012. Pfhrp2 and pfhrp3 gene and their flanking genes on chromosomes 7 and 13, respectively, were amplified from 198 blood specimens collected in Brazil. In Brazil, the isolates collected in Acre state, located in the western part of the Brazilian Amazon, had the highest percentage of deletions for pfhrp2 25 (31.2%) of 79, while among those collected in Rondonia, the prevalence of pfhrp2 gene deletion was only 3.3% (2 out of 60 patients). In isolates from Para state, all parasites were pfhrp2-positive. In contrast, we detected high proportions of isolates from all 3 states that were pfhrp3-negative ranging from 18.3% (11 out of 60 samples) to 50.9% (30 out of 59 samples). In Bolivia, only one of 25 samples (4%) tested had deleted pfhrp2 gene, while 68% (17 out of 25 samples) were pfhrp3-negative. Among the isolates tested, P. falciparum pfhrp2 gene deletions were present mainly in those from Acre State in the Brazilian Amazon. These results indicate it is important to reconsider the use of PfHRP2-based RDTs in the western region of the Brazilian Amazon and to implement appropriate surveillance systems to monitor pfhrp2 gene deletions in this and other parts of the Amazon region.

Neotropical echinococcosis: second report of Echinococcus vogeli natural infection in its main definitive host, the bush dog (Speothos venaticus).

The bush dog (Speothos venaticus) acts as the natural definitive host in the life cycle of Echinococcus vogeli, the causative agent of polycystic hydatid disease, a zoonotic neglected disease in the South America. We report a case of natural infection by Echinococcus vogeli in a bush dog from the Brazilian Amazon, confirmed by the morphological and morphometric examination of adult parasites and their hooks obtained from the small intestine of the canid. Additionally, mitochondrial DNA sequence analysis corroborated these findings. This is the second report of natural infection by E. vogeli in a bush dog.

Prospección fitoquímica y actividad antiplasmódica del extracto hexánico de Montrichardia linifera (Arruda) Schott / Phytochemical prospection and antiplasmoidal activity of the hexane extract from Montrichardia linifera (Arruda) Schott

Introducción: los extractos de M. linifera presentaron alta toxicidad para Artemia salina, lo cual sugiere un alto potencial biológico para actividad antitumoral, antibacteriana, antifúngica y actividad contra el Trypanosoma cruzi. Objetivo: evaluar el potencial antimalárico del extracto hexánico obtenido de hojas de Montrichardia linifera (Arruda) Schott y conocer su perfil fitoquímico. Métodos: la prospección fitoquímica se realizó por el método de precipitación y la actividad antiplasmódica fue evaluada in vitro utilizando el clon W2 de Plasmodium falciparum. Resultados: la prospección fitoquímica sugirió solamente la presencia de esteroides. En relación con la actividad antiplasmódica, después de 24 h en la concentración de 100 µg/mL la inhibición del crecimiento parasitario fue de 50,5 por ciento y en las demás no fue observada una inhibición significativa. En 48 h, en la concentración de 100 µg/mL, la inhibición del crecimiento fue de 34,7 por ciento. Después de 72 h las concentraciones de 100 y 50 µg/mL presentaron hemólisis, que imposibilitó la determinación porcentual parasitada. Conclusiones: el extracto hexánico obtenido de las hojas de M. linifera tiene un bajo potencial antimalárico y mostró positivamente esteroides.

Introduction: Montrichardia linifera extracts showed high toxicity to Artemia salina, which indicated high biological potential for antitumoral, antibacterial, antifungal activities, and action against Trypanossoma cruzi. Objective: to evaluate the antimalarial potential of the hexane extract from the Montrichardia linifera (Arruda) Schott leaves and to discover its phytochemical profile. Methods: the phytochemical prospection was conducted by the precipitation method whereas the antiplasmodial activity was evaluated in vitro using the W2 Plasmodium falciparum clone. Results: the phytochemical prospection just suggested the presence of steroids. Regarding the antiplasmodial activity after 24 hours at 100 µg/mL concentration, the parasite growth inhibition was 50.5 percent but at other concentration ranges, significant inhibition was not observed. At 48 hours, the growth inhibition at 100 µg/mL concentrations was 34.7 percent. After 72 hours, hemolysis was observed at 100 µg/mL and 50 µg/mL concentrations, so the percentage determination of the parasites was not possible. Conclusions: the hexane extract obtained from the M. linifera leaves presented with low antimalarial potential and proved to be positive for steroids.