Resumo O presente estudo teve como objetivo caracterizar a composição florística e fitossociológica de um trecho de Floresta Ombrófila Densa de terra firme na área de influência da Usina Hidrelétrica Belo Monte, Pará, Brasil. Foram inventariadas todas as árvores com DAP > 10 cm em 75 parcelas permanentes de 1 ha. Foram observados 27.126 indivíduos arbóreos (361 ind.ha-1), distribuídos em 59 famílias botânicas, perfazendo 481 espécies. As famílias com maior número de espécies foram Fabaceae (94), Araceae (65) e Arecaceae (43), perfazendo 43,7% do total de espécies amostradas. As espécies Alexa grandiflora (4,41), Cenostigma tocantinum (2,50), Bertholletia excelsa (2,28), apresentaram os maiores valores de importância (VI), sendo que nas dez espécies com maiores IV, estão concentrados 22%. A comunidade florestal apresenta elevada riqueza florística e pode ser classificada como multiâneas, heterogêneas e com médio estado de conservação.

Abstract The objective of the present study was to characterise the floristic and phytosociological composition on a stretch of dense “Terra Firme” rainforest located in the Belo Monte hydroelectric plant area of influence, located in the state of Pará, Brazil. All trees with DAP >10 cm situated in 75 permanent plots of 1 ha were inventoried. 27,126 individuals trees (361 ind.ha-1), distributed in 59 botanical families, comprising 481 species were observed. The families with the largest number of species were Fabaceae (94), Araceae (65) and Arecaceae (43), comprising 43.7% of total species. The species Alexa grandiflora (4.41), Cenostigma tocantinum (2.50) and Bertholletia excelsa (2.28) showed the highest importance values (IV). The ten species with greater IV are concentrated (22%). The forest community has high species richness and can be classified as diverse age trees, heterogeneous and of medium conservation condition.

Sixteen PAH compounds (containing three to six rings) were quantified in sediments from the Rosário and Mitrena salt marshes in the Tagus and Sado estuaries, respectively, colonized by Sarcocornia fruticosa, and in belowground and above-ground plant tissues. Sediments from Rosário presented higher PAH concentrations (0.83-8.71 μg g-1) than those from Mitrena (0.22-1.63 μg g-1). Levels in belowground plant tissues showed a pronounced contrast between the two marshes: 84-165 and 0.15-0.43 μg g-1, respectively. Belowground material in contaminated layers contained 9-55 times more PAHs than sediments, while ratios lower than one were obtained in lower contaminated layers. Five- and six-ring compounds predominated (60-75%) in sediments and belowground plant material from both sites. Aboveground plant tissues presented no differences in PAH concentrations (0.17-0.18 ng g-1) and composition in both marshes, only three- and four-ring compounds being detected. This narrow concentration range appears to indicate that atmospheric deposition is the predominant pathway of PAH accumulation in aerial plant tissues.

Se cuantificaron 16 hidrocarburos aromáticos policíclicos (PAHs, por sus siglas en inglés; con tres a seis anillos) en sedimentos de las marismas de Rosário y Mitrena, de los estuarios del Tajo y el Sado, respectivamente, y en los tejidos subterráneos y aéreos de Sarcocornia fruticosa, una planta que habita en estas marismas. Los sedimentos de Rosário presentaron mayores concentraciones de PAHs (0.83-8.71 μg g-1) que los de Mitrena (0.22-1.63 μg g-1). Los niveles de PAHs en los tejidos vegetales subterráneos mostraron un contraste pronunciado entre los dos sitios: 84-165 μg g-1 y 0.15-0.43 μg g-1, respectivamente. El material subterráneo de las capas contaminadas contuvo de 9 a 55 veces más PAHs que los sedimentos, mientras que en las capas menos contaminadas se obtuvieron razones menores a 1. Los componentes con cinco y seis anillos predominaron (60-75%) en los sedimentos y en el material vegetal subterráneo de ambas marismas. En ninguna de ambas marismas los tejidos vegetales aéreos presentaron diferencias entre las concentraciones (0.17-0.18 ng g-1) ni en la composición de PAHs, detectándose sólo compuestos de tres y cuatro anillos. Este estrecho intervalo de concentraciones parece indicar que los depósitos atmosféricos son la vía predominante de acumulación de PAHs en los tejidos aéreos de las plantas.

In a study of congenital transmission during acute infection of Toxoplasma gondii, 23 pregnant Balb/c mice were inoculated orally with two cysts each of the P strain. Eight mice were inoculated 6-11 days after becoming pregnant (Group 1). Eight mice inoculated on the 10th-15th day of pregnancy (Group 2) were treated with 100 mg/kg/day of minocycline 48 h after inoculation. Seven mice inoculated on the 10th-15th day of pregnancy were not treated and served as a control (Group 3). Congenital transmission was evaluated through direct examination of the brains of the pups or by bioassay and serologic tests. Congenital transmission was observed in 20 (60.6%) of the 33 pups of Group 1, in one (3.6%) of the 28 pups of Group 2, and in 13 (54.2%) of the 24 pups of Group 3. Forty-nine Balb/c mice were examined in the study of congenital transmission of T. gondii during chronic infection. The females showed reproductive problems during this phase of infection. It was observed accentuated hypertrophy of the endometrium and myometrium. Only two of the females gave birth. Our results demonstrate that Balb/c mice with acute toxoplasmosis can be used as a model for studies of congenital T. gondii infection. Our observations indicate the potential of this model for testing new chemotherapeutic agents against congenital toxoplasmosis.