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Recebido em 7/6/11; aceito em 10/11/11; publicado na web em 28/2/12 BIOMONITORING OF Cr AND Pb IN FRESHWATER FISH. Trace metal content of three fish species harvested from a tank located in the City of Guarapuava-PR, Brazil were determined by digestion and voltametry. Trace metal content in fish samples were 0.10-1.30 µg/g (muscle) and 0.45-15.90 µg/g (liver) for chromium, 0.35-2.56 µg/g (muscle) and 2.32-34.30 µg/g (liver) for lead. The levels of lead and chromium in fish samples were higher than the recommended legal limits for human consumption. To assess the dietary intake of Cr and Pb by fish, weekly intake was calculated based on average metals contents and weekly consumption of fish and it compared with PTWI (Provisional Tolerable Weekly Intake). The Cr and Pb have achieved up to 25 and 45%, respectively, of PTWI recommended by WHO/FAO. Keywords: metals; fish; voltametry. INTRODUÇÃOOs elementos Cr e Pb estão presentes na natureza através do intemperismo ou por atividades industriais e de mineração. Esses elementos podem exercer efeitos prejudiciais para a biota, dependendo da concentração.1,2 O crômio no estado trivalente é benéfico em pequenas quantidades, participando do metabolismo do corpo humano, mas no estado de oxidação hexavalente possui ação cancerígena. O chumbo é de grande interesse ambiental, pois está presente em concentrações consideráveis no meio urbano. Com relação a sua toxicidade, atua principalmente no sistema nervoso central.Muitos organismos apresentam um forte potencial para bioconcentrar níveis elevados de metais a partir de seu ambiente. Monitorar ambientes aquáticos através do uso de bioindicadores tem sido objeto de considerável interesse nos últimos anos, devido à preocupação de que os níveis elevados dos metais podem ter efeitos prejudiciais sobre vários organismos e também por criar problemas em relação à sua adequação como alimento para seres humanos. [3][4][5] Os peixes podem ser usados como indicadores biológicos, pois sofrem bioacumulação e biomagnificação por metais. Esses organismos são capazes de armazenar quantidades de substâncias nocivas, sem sofrer danos e servem como indicadores de contaminação para avaliar a qualidade da água em ambientes aquáticos. Segundo Esser, 6 a bioacumulação trata da capacidade de acumular uma substância, através do meio circundante ou de seu alimento por um dado organismo, enquanto que a biomagnificação consiste da transferência de uma substância química de um nível trófico inferior para um superior.Os peixes estão localizados no final da cadeia alimentar aquática, podem acumular metais e passá-los para seres humanos através da alimentação, causando doenças crônicas ou agudas. O tempo de permanência em águas poluídas, a idade e o seu tamanho afetam o acúmulo de metais pesados em seus organismos. O objetivo deste estudo foi elucidar a extensão da poluição causada por efluente de curtume descartado em um ambiente aquático localizado em Guarapuava -PR, Brasil. Esse efluente, rico em sais de Cr, é liberado no rio sem tratamento prévio há mais ...

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In this manuscript we briefly describe bipolar disorder (a depressive and manic mental disease), its classification, its effects on the patient, which sometimes include suicidal tendencies, and the drugs used for treatment. We also address the status quo with regard to diagnosis of bipolar disorder and recent advances in bioanalytical approaches for biomarker discovery. These approaches focus on blood samples (serum and plasma) and proteins as the main biomarker targets, and use various strategies for protein depletion. Strategies include use of commercially available kits or other homemade strategies and use of classical proteomics methods for protein identification based on "bottom-up" or "top-down" approaches, which used SELDI, ESI, or MALDI as sources for mass spectrometry, and up-to-date mass analyzers, for example Orbitrap. We also discuss some future objectives for treatment of this disorder and possible directions for the correct diagnosis of this still-unclear mental illness.

The concentrations of Cr and Pb were determined in bryophytes and pteridophytes sampled in a stream near a tannery in Guarapuava, southern Brazil. The concentrations of Cr and Pb were measured by cathodic and anodic voltammetry, respectively. These plants were used to evaluate the spatial distribution of elements in the examined stream, and contained elevated levels of Cr (0.71-24.07 μg/g) and Pb (4.33-24.20 μg/g). Chromium levels in plants near the tannery greatly exceeded background levels, indicating a severe to extreme degree of contamination with this metal. Lead levels were elevated to a lesser degree, indicating slight to moderate contamination for most plants collected near the tannery.

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1. Ecological restoration of tropical open ecosystems remains challenging for both science and practice. Over the last decade, innovative techniques have been developed, but whether they have been successful or not remains to be demonstrated. Assessing the outcomes of these initiatives is crucial to drive the following steps to improve tropical grasslands and savanna restoration. 2. Analysing 82 data sets from the literature and primary data collection, we assessed the effectiveness of passive and active restoration techniques applied in Cerrado open ecosystems. We used plant diversity variables (species and growth forms) as indicators, considering ruderals and exotics as non-target species. Specifically, we aimed to answer: (i) How does the diversity of target species change through time in areas subject to passive restoration? (ii) Are active and passive restoration techniques effective in restoring the proportion of target species found in oldgrowth reference ecosystems? (iii) Have the current techniques been successful in recovering the proportions of growth forms of reference ecosystems?3. We found that target species proportions do not increase with time, suggesting limitations of typical species to colonise degraded sites. Hence, passive restoration will promote the conservation of a limited and constant number of target species. This number will depend on the magnitude of degradation and previous land use. 4. The restoration techniques currently applied to restore the biodiversity of Cerrado open ecosystems are not reaching the reference standards, with distinct techniques driving plant communities to different sets of growth forms. Active restoration based on propagules obtained from pristine donor sites (topsoil translocation, plant material transplant, and seeding) performed better than passive restoration for most of the growth forms analysed.

Tropical grasslands have been systematically neglected worldwide in maps, conservation policies, and ecological studies. After eradicating invasive pine trees from a Cerrado reserve in southeastern Brazil, an unprecedented grassy ecosystem arose in recent satellite images. In the field, we confirmed the first record of wet grasslands with termite mounds – locally named campo com murundus ˗ beyond 21°S in the São Paulo state. Besides reporting this occurrence, we sampled the two plant communities forming this peculiar vegetation type (the mounds and the waterlogged matrix around them) to investigate if they are floristically and functionally distinct. We also explored how these two communities relate to those of the surrounding open vegetation types (savanna, dry and wet grassland). Woody plants were recorded on the mounds but not in the matrix, although the two communities share some ground layer species. Compared to the adjacent vegetation types, the mounds were floristically distinct and functionally more balanced in growth forms, dispersal syndrome, and tolerance to waterlogging. We hope this borderline record of campo com murundus can stimulate the search for other unnoticed remnants out of their known occurrence region, triggering efforts for their conservation and studies to improve comprehension of these iconic ecosystems.