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The presence of cyanobacterial blooms and their subproducts interferes directly in water quality and may cause negative effects, both aesthetically and to public health, due to the production of potentially toxic and carcinogenic compounds. The most common type of intoxication involving cyanobacteria is caused by microcystin-LR (hepatotoxin), which can cause severe damage to the liver. The objective of this study was to identify the genera that caused cyanobacterial blooms in the Tapajós river (Santarém, Pará, Brazil) in March 2007, as well as to execute acute toxicity bioassays in Swiss-webster mice. Sample collection was performed at five sampling points throughout the left margin of the Tapajós river, by horizontal dragging with the aid of a 20 µm plankton net. Samples of raw water (5,000 ml) were also collected in amber propylene bottles. Optical microscopy was applied to identify the organisms, and the determination of microcystin-LR was executed through ELISA and HPLC. The analyses showed that, at P01 and P02, there was an ecological imbalance in the phytoplanktonic community, characterized by an intense proliferation of the genera Anabaena and Microcystis. The concentrations of microcystin-LR reported in the raw water samples were below the maximum values permitted by Brazil's legislation for drinking water. However, it is important to note that the blooming observed in loco occupied around 10 cm of the water column surface and therefore presented cyanobacterial cells enough to cause rashes in people who swam or bathed in the rivers during this period.

Human T-cell lymphotropic virus type 1 is transmitted primarily either through sexual intercourse or from mother to child. The current study investigated sexual transmission and compared the HTLV-1 proviral load between seroconcordant and serodiscordant couples by examining both men and women among the index partners without using subjective criteria to establish the direction of sexual transmission. Between January 2013 and May 2015, 178 HTLV-1-positive patients had spouses, 107 of which had tested partners, thus increasing the initial sample size (46 men and 61 women). Individuals co-infected with HTLV-2 or human immunodeficiency virus were not included in the analysis. From among the included participants, 26 men and 26 women were paired with each other, resulting in 26 seroconcordant couples; 12 seroconcordant couples were formed from another four men and eight women. Forty-three serodiscordant couples were formed from 16 men and 27 women. The rate of seroconcordance was 46.9%. The HTLV-1 proviral load was compared between 19 and 37 seroconcordant and serodiscondant couples, respectively, and the concordant couples showed higher proviral loads (P = 0.03). There were no differences between the groups according to age, relationship length, having a mother or sibling with HTLV-1, race, ethnicity, nationality, education, history of blood transfusion, HAM/TSP, ALT, or hepatitis C virus status. In multivariate analysis, relationship time was shown associated with ocurrence of seroconcordance status. The apparent association between high circulating levels of provirus and seroconcordance rate among couples suggests that proviral loads contribute markedly to the risk of sexual transmission, regardless of gender index.

Este trabalho descreve os aspectos sociais, econômicos e ambientais de uma comunidade de pescadores(Vila dos Pescadores), situada no estuário do Rio Caeté, no nordeste do Pará (Brasil). A metodologiaadotada neste estudo foi baseada em entrevistas, questionários e observação direta para caracterizaralguns aspectos sociais, econômicos e ambientais, bem como no monitoramento de perfis de praia,para determinar a dinâmica costeira local. Os resultados mostram que a maioria dos entrevistados tementre 18 e 35 anos (50,97%), são pescadores (62,13%), casados (68,93%), com 1° grau incompleto(77,67%), moram com a família (2-4 pessoas, 39,8%), em casa própria (86,89%) e ganham menos de1 salário mínimo (95,63%). A maioria habita a vila há 3 anos ou mais (42,71%) e não está satisfeitacom a atual situação social, econômica e ambiental. A vila apresenta alguns problemas ambientais,como erosão costeira, e sérios problemas de serviços e infra-estrutura (p. ex. transporte público, telefonespúblicos, coletores de lixo, iluminação pública, água potável, saneamento básico, comércio, áreapara lazer, posto de saúde, estacionamento, salva-vidas, escolas, etc.). A ausência de emprego favoreceque a pesca seja a principal atividade econômica da vila. Por outro lado, a natureza exuberante, oclima equatorial, a tranqüilidade e a abundância de peixes são aspectos positivos segundo a opiniãodos entrevistados.

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The port regions of the Amazon are subject to environmental impacts high shipping traffic. In October 2015, a cargo ship containing 5000 oxen sank in the Port of Vila do Conde, northern Brazil, releasing large amounts of organic matter and diesel oil into the aquatic environment. We evaluated the consequences of this shipwreck on the zooplankton community. Sampling was carried out using a phytoplankton net (64 μm) at two locations close to the port. We calculated the frequency of occurrence, relative abundance, and trophic state index and performed a canonical redundancy analysis of zooplankton in this area. Total density values ranged from 371 to 8600 organisms/m 3 , with minimum values being recorded during the period of the shipwreck and maximum values after the shipwreck. The areas categorized as super eutrophic had the lowest density values. The most abundant species/groups were nauplii and copepodites of the orders Cyclopoida and Calanoida. Of the environmental variables, only biochemical oxygen demand, chemical oxygen demand, and total dissolved solids were selected by the redundancy canonical analysis. The environmental conditions of the region and the ongoing environmental impacts might substantially influence the structure of the zooplankton community. The predominance of these organisms, in addition to the high densities of nauplii and copepodites, was likely related to the large amounts of nutrients generated by the shipwreck.

The study characterized and evaluated the use of the benthic macroinvertebrate community as an indicator of impacts in different estuarine environments around the Industrial Port Complex (IPC) of Vila do Conde (Pará State, Amazon region). Fauna of beaches and rivers, in sectors of the estuary under different degrees of environmental impact (high, medium, and low), was compared in different seasonal periods. Macrofauna was composed of typically fresh-water and estuarine groups. Beaches presented sediment with a texture ranging from medium to coarse sand, with a less rich macrofauna ( = 4.5 ± SE 0.3 taxa/sample) and dense ( = 1,838.1 ± 164.8 ind./m2) of organisms when compared to rivers ( = 5.9 ± 0.3 taxa/sample, and 3,248.9 ± 77.0 ind./m2), which were environments more muddy. For both environments, sites in the high-impact sector were less rich ( = 4.7 ± 0.3 taxa/sample) and dense ( = 2,812.9 ± 232.7 ind./m2) when compared to those in the low-impact sector ( = 7.6 ± 0.4 taxa/sample, and 3,314.3 ± 230.1 ind./m2). Richness ( = 6.4 ± 0.3 taxa/sample) and density ( = 3,859.4 ± 190.2 ind./m2) were higher in the rainier season when compared to the less rainy season ( = 4.8 ± 0.3 taxa/sample, and 1,933.0 ± 172.1 ind./m2). However, there were no significant seasonal changes in composition. Results indicated that the structure of the benthic macroinvertebrate community surrounding the IPC responds to the loss of environmental quality, with extreme effects of a drop in abundance and diversity. Taxa that are more tolerant (Namalycastis caetensis, Cirolana sp., Pseudosphaeroma sp., Tubificidae, and Chironomidae) and sensitive (Hydropsychidae and Eteone sp.) to impact conditions were identified and evaluated as potential bioindicators.