Effect of seasonality and estuarine waters on the phytoplankton of the Guamá River (Belém, Amazon, Brazil).

This study aimed to analyze the application of the Phytoplankton Community Index-PCI and Functional Groups-FG in determining the water quality of the Guamá River (Pará, Amazônia, Brazil). Samplings occurred monthly for analyses of phytoplankton and physical and chemical parameters, for two years, at the station where water was collected for human supply consumption. Seasonality influenced electrical conductivity, total suspended solids, dissolved oxygen, transparency, winds, true color, and N-ammoniacal. The ebb tide showed high turbidity and suspended solids. The density varied seasonally with the highest values occurring in September and December (61.1 ind mL-1 and 60.2 ind mL-1, respectively). Chlorophyll-a was more elevated in December (21.0 ± 4.7 µg L-1) and chlorophyll-c higher in relation to clorophyll- b indicated the dominance of diatoms. Functional Group P prevailed in the study months. Through the PCI índex the waters of Guamá River varied from reasonable to excellent and the TSI ranged from oligo to mesotrophic. The use of Functional Groups proved to be a promising tool in the determination of water quality since it covered the most abundant species in the Environment, but the PCI is not adequate to characterize Amazonian white-waters rivers, which have diatoms as the leading dominant group.

High risk of heterosexual transmission of human T-cell lymphotropic virus type 1 infection in Brazil.

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.

Effects of a shipwreck on the zooplankton community in a port region of the Amazon.

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/m3, 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.

Late cytomegalovirus infection after hematopoietic stem cell transplantation: case reports.

Cytomegalovirus is related to high rates of morbidity and mortality after hematopoietic stem cell transplantation. This report highlights the importance of adequate monitoring and management of this infection. We report on two cases of patients with late subclinical cytomegalovirus infection. These patients were monitored for antigenemia by indirect immunofluorescence assay. Active cytomegalovirus infection is most common in the first three months after transplantation however the cases reported herein show the importance of monitoring for active infection after Day +100 post-transplantation. Early detection of active infection enables quick preemptive therapy. In conclusion, we emphasize that patients with risk factors for developing severe or late cytomegalovirus disease should be monitored for more than 100 post-transplant days as late active infection is a reality.

Late cytomegalovirus infection after hematopoietic stem cell transplantation: case reports

Cytomegalovirus is related to high rates of morbidity and mortality after hematopoietic stem cell transplantation. This report highlights the importance of adequate monitoring and management of this infection. We report on two cases of patients with late subclinical cytomegalovirus infection. These patients were monitored for antigenemia by indirect immunofluorescence assay. Active cytomegalovirus infection is most common in the first three months after transplantation however the cases reported herein show the importance of monitoring for active infection after Day +100 post-transplantation. Early detection of active infection enables quick preemptive therapy. In conclusion, we emphasize that patients with risk factors for developing severe or late cytomegalovirus disease should be monitored for more than 100 post-transplant days as late active infection is a reality.

Ocorrência de uma floração de cianobactérias tóxicas na margem direita do Rio Tapajós, no Município de Santarém (Pará, Brasil) / Occurrence of toxic cyanobacterial bloom in the left margin of the Tapajós River, in the Municipality of Santarém (Pará State, Brazil)

A presença de florações de cianobactérias e seus subprodutos interfere diretamente na qualidade da água, podendo introduzir efeitos negativos, tanto de ordem estética, como de saúde pública, devido à produção de compostos potencialmente tóxicos e carcinogênicos. O tipo mais comum de intoxicação envolvendo cianobactérias é ocasionado por microcistina-LR (hepatotoxina), a qual pode causar severos danos ao fígado. Assim, o objetivo deste estudo foi identificar os gêneros causadores de uma floração de cianobactérias no Rio Tapajós (Santarém, Pará, Brasil) no mês de março de 2007, bem como realizar bioensaios de toxicidade aguda, utilizando camundongos Swiss-webster. As amostragens foram realizadas em cinco pontos de coleta distribuídos na margem direita do Rio Tapajós, onde foram realizados arrastos horizontais, com o auxílio de uma rede para plâncton de 20 μm; e foram também coletadas amostras de água bruta (5.000 mL) em garrafas de polipropileno do tipo âmbar. Para a identificação dos organismos utilizou-se microscopia ótica. A determinação de microcistinas-LR foi realizada por meio das técnicas de Ensaio Imunoadsorvente Enzima-Associado e Cromatografia Líquida de Alta Pressão. As análises demonstraram que na altura dos pontos P01 e P02 ocorreu um desequilíbrio ecológico na comunidade fitoplanctônica, caracterizado pela proliferação intensa dos gêneros Anabaena e Microcystis. Nas amostras de água bruta, as concentrações de microcistina-LR registradas estão abaixo dos valores máximos permitidos na legislação brasileira para água de consumo; entretanto, é importante ressaltar que a floração, visualizada in locu, ocupava cerca de 10 cm da superfície da coluna d'água, e que, portanto, continha células de cianobactérias suficientes para provocar irritações cutâneas em pessoas que usassem o rio como balneário nesse período.

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 locu 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.