Publications by authors named "Florentino A"

Macapá City, located in the Brazilian Amazon, faces critical aquatic pollution challenges due to inadequate sanitation infrastructure, leading to metal contamination in fish within its urban water bodies. Our study evaluated the concentrations of metals (Cu, Cd, Cr, Fe, Mn, Ni, Pb, Zn, and Hg) in muscle tissues of fish from igarapés, ressaca areas, and canals. Samples were collected from six sampling sites to investigate the bioaccumulation of these metals and their potential human health risks.

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While not essential for most plants, sodium (Na) can partially substitute for potassium (K) in some metabolic functions. Thus, understanding the mechanisms underlying K and Na uptake, transport, utilization, and ion replacement is crucial to sustain forest production. A pot experiment was designed with 6 K/Na ratios (100/0, 85/15, 70/30, 55/45, 40/60, and 0/0%) and two water conditions (well-watered, W+; and water-stressed, W-) on two Eucalyptus species with contrasting drought tolerance.

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Article Synopsis
  • Mercury contamination in the Amazon is a serious public health issue caused by natural sources and mining, particularly in areas where gold is extracted using mercury.
  • A systematic review of literature from 2017 to 2023 published identifies significant levels of mercury in predators like fish and in human hair, with findings showing concentrations well above safety limits.
  • The study highlights the need for ongoing research and monitoring of mercury levels, particularly in fish consumed by local populations, due to their reliance on fish as a primary protein source.
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Adaptive responses to abiotic stresses such as soil acidity in Eucalyptus-the most widely planted broad-leaf forest genus globally-are poorly understood. This is particularly evident in physiological and anatomical disorders that inhibit plant development and wood quality. We aimed to explore how the supply of Ca and Mg through liming (lime), combined with Cu and Zn fertilization (CZF), influences physiological and anatomical responses during Eucalyptus grandis seedlings growth in tropical acid soil.

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In this bioremediation study, the fungus sp. isolated from kefir grains was evaluated for its resistance to copper in the culture medium. sp.

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The Araguari River, one of the most important waterways in the Brazilian state of Amapá, is ecologically relevant and essential for the conservation of Amazonian fish biodiversity. Our previous studies demonstrated contamination of water and fish by metals. In particular, water samples showed genotoxic damage in Danio rerio.

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Baicalein (BA) is a flavonoid with wide-ranging pharmacological activity. However, its biological evaluation is hampered by its low solubility in aqueous medium, making forms of incorporation that improve its solubility necessary. In the present study, BA was combined with a solution of silk fibroin protein (SF), a biomaterial used too as a drug carrier, to evaluate the anti-inflammatory potential of this combination, in vivo, in an experimental model, zebrafish (Danio rerio).

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Mosquitoes can be vectors of pathogens and transmit diseases to both animals and humans. Species of the genus Culex are part of the cycle of neglected diseases, especially Culex quinquefasciatus, which is an anthropophilic vector of lymphatic filariasis. Natural products can be an alternative to synthetic insecticides for vector control; however, the main issue is the poor water availability of some compounds from plant origin.

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Recently, high concentrations of metals have been found in the waters from sampling sites located in the Araguari River lower section. These metals can be bioaccumulated by fish, but also biomagnified, representing a potential risk through human consumption. Here, we aimed to (1) determine the metal concentrations in muscle samples from fish; (2) evaluate bioaccumulation of metals in muscle tissue of fish species with different feeding behaviors; and (3) investigate the risks of single metals, as well as mixture of metals, to human fish consumption.

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Amazonian aquatic environments are seriously impacted by dam-building and deforestation, among other threats. Therefore, the present study aimed to examine water quality in the middle and lower course of the Araguari River with respect to the composition of vegetative cover and the concentration of As, Cd and Hg in order to determine risks to the preservation of biota and risks to human health from consumption of P. squamosissimus contaminated with these inorganic elements.

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This work aimed to investigate the partial K-replacement by Na supply to alleviate drought-induced stress in Eucalyptus species. Plant growth, leaf gas exchange parameters, water relations, oxidative stress (HO and MDA content), chlorophyll concentration, carbon (C) and nitrogen (N) isotopic leaf composition (δC and δN) were analyzed. Drought tolerant E.

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The objective of this study was to quantify the effect of potassium (K) supply on osmotic adjustment and drought avoidance mechanisms of Eucalyptus seedlings growing under short-term water stress. The effects of K supply on plant growth, nutritional status, leaf gas exchange parameters, leaf water potential (Ψw), leaf area (LA), stomatal density (SD), leaf carbon (C) and nitrogen (N) isotopic compositions (δ13C and δ15N ‰) and leaf C/N ratio under polyethylene glycol (PEG)-induced water deficit were measured. Under both control (non-PEG) and osmotic stress (+PEG) conditions, K supply increased plant growth, boosting dry matter yield with decreased C/N leaf ratio and δ15N ‰ values.

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The Araguari River is one of the most important water body in the Brazilian state of Amapá. However, the quality of its waters has been deteriorating and, recently, high concentrations of metals were found in water samples collected from its lower section. Overall, we aimed to evaluate land use and cover around three sampling sites located in the Araguari River lower section and its contribution to water pollution by metals; correlate land use pattern with detected metal concentrations; assess acute toxicity using the Daphnia similis test and genotoxicity using the Danio rerio bioassay of water samples from the three sampling sites; and investigate the risks arising from metals present in waters to aquatic biota.

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This study compared the rates and microbial community development in batch bioassays on autotrophic denitrification using elemental sulfur (S), pyrite (FeS), thiosulfate (SO ), and sulfide (S) as electron donor. The performance of two inocula was compared: digested sludge (DS) from a wastewater treatment plant of a dairy industry and anaerobic granular sludge (GS) from a UASB reactor treating dairy wastewater. All electron donors supported the development of a microbial community with predominance of autotrophic denitrifiers during the enrichments, except for sulfide.

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This study used information about Procamallanus (Spirocamallanus) inopinatus Travassos, Artigas & Pereira, 1928 that had been published over a period of more than 90 years to investigate the infection and distribution patterns of this nematode in teleost freshwater fish in Brazil. This study was carried out using 181 samples from 82 fish species in 19 families within the five orders, with predominance of Characiformes species (71.6%).

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This study aimed to determine the concentration of metals in the water and in the liver tissue of fish (Anodus orinocensis, Hemiodus unimaculatus, Curimata vittata, and Plagioscion squamosissimus) in the lower Araguari River. Steps were also taken to estimate any difference in metal bioaccumulation in the liver of fish species at different trophic levels, determine any correlations between metals found in hepatic tissue of fish species relative to that found in river water, and evaluate the bioaccumulation factor. The metals analyzed in the water in the lower Araguari River (Cd, Pb, Fe, Hg, Cu, and Zn) exceeded the limits considered safe for aquatic life.

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This research assessed the microbiological suitability of oleate degradation coupled to sulfidogenesis by enriching communities from anaerobic sludge treating dairy products with S, , , and S as electron acceptors. The limiting factor hampering highly efficient oleate degradation was investigated in batch reactors. The best sulfidogenic performance coupled to specialization of the enriched bacterial community was obtained for S- and S -reducing enrichments, with 15.

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Glutathione (GSH) plays critical roles in the inflammatory response by acting as the master substrate for antioxidant enzymes and an important anti-inflammatory agent. In the early phase of the inflammatory response of macrophages, GSH content is decreased due to the down regulation of the catalytic subunit of glutamate cysteine ligase (GCLC). In the current study we investigated the underlying mechanism for this phenomenon.

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The Amazon represents one of the most complex biomes in the world; however, the temporal variations in parasite community structure of fishes inhabiting this region remain poorly understood. Therefore, processes generating such variations are still unknown. The present study evaluated the long-term temporal variation of community structure of metazoan parasites of Pimelodus blochii collected in Iaco River, State of Acre (Southwestern Brazilian Amazon).

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Objective:  To evaluate the existence of an association between ultrasound findings and epidemiological and clinical factors using results obtained from the EHP-30 questionnaire in women with ovarian endometriosis.

Methods:  A cross-sectional observational study was performed between July 2012 and May 2015, in which patients with chronic pelvic pain suggestive of endometrioma, as indicated by the results from a transvaginal pelvic ultrasonography, completed the standardized Endometriosis Health Profile - 30 (EHP-30) questionnaire to access quality-of-life scores before beginning treatment for endometriosis. A total of 65 patients were included.

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This study investigated the effect of granular activated carbon (GAC) on the digestion of blackwater collected from different collection systems, by monitoring the biochemical methane production (BMP), adsorption of molecules to GAC and their impacts on the microbial community. Without GAC-amendment, BMP reached 35.6, 42.

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