Avaliação dos efeitos de um extrato bruto de cianobactérias contendo microcistinas sobre o desempenho reprodutivo e a embriofetotoxicidade de ratos

The presence of cyanobacterial blooms in reservoirs intended for supply to the population can create public health problems for many species could produce potentially toxic compounds and these are not eliminated in the conventional procedures used in water treatment plants. So even in amounts less than the maximum allowable limit imposed by MS, cyanotoxins can be present in drinking water distributed to the population, creating a chronic exposure. There is little information about the long-term effects of oral exposure to cyanotoxins. This work aimed to show the exposure orally (v.o) of animals to a crude extract of cyanobacteria containing cyanotoxins to evaluate the reproductive performance of pregnant rats and their offspring and fertility of male rats. The presence of microcystins (MCs) in samples collected during the flowering processes in freshwater reservoirs in the Rio Grande do Norte, was analyzed by enzyme immunoassay and its variants have been identified and quantified by chromatographic methods. It was observed that by administration v.o. cyanobacterial extract containing MCs (40, 100 or 250 ng of MCs / kg / day) did not cause systemic toxicity in adult rats or effect on reproductive performance of male and female rats treated. It was also not observed any changes in skeletal study in the offspring of pregnant rats treated with the extract above. Because the solutions used contained MCs in a concentration equal to or greater than the tolerable daily intake for MCs, the results suggest, therefore, that the development of this work contributed to better assess public health risk as the oral exposure to cyanotoxins, increasing thus the credibility of the maximum allowable limit (LMP) of MCs in drinking water distributed to the population of several countries that use the LMP established by WHO in its legislation

Avaliação da genotoxicidade das águas do lençol freático sob a Universidade Federal do Rio Grande do Norte

The groundwater represents the most important freshwater supply of planet. Dailly, in all world a great amount of toxic and genotoxic material reaches the aquatic systems, mainly the aquifers. The Barreiras aquifer through of five water wells is responsible for the supplying of Universidade Federal do Rio Grande do Norte (UFRN). All water wells are polluted with nitrate and some heavy metals, two of them were disabled. The genotoxicity of groundwater samples from Barreiras Aquifer in UFRN was assessed using the Allium cepa test, the Ames test and the Salmonella typhymurium microsuspension test (Kado test). For the Allium cepa test the influence of the groundwater samples collected on macroscopic (root length, colour and form) and microscopic (root tip mitotic index, chromosome aberrations and micronucleus) parameters was examined. All water samples caused a significant increase of the chromosome and mitotic aberration frequency and reduction on the rooth growth compared to negative control. Bridges and chromosome stickness were the most frequent kind of aberration in dividing cells. Furthermore, breaks were also observed. No significant increase in the number of micronuclei was found in relation to the negative controls. For Ames test were used the Salmonella typhymurium strains TA98 and TA100 without metabolic activation, applying the direct method. Prior to the Kado test, organic fractions from the water samples were obtained through XAD resin concentration. The mutagenicity organic extracts were evaluated by Kado test using TA98 and TA100 strains, in the absence and presence of S9 mix (metabolic activation). The concentrations of seven heavy metal ions were measured in water samples, but only Ni, Cu and Cr levels exceeded the permissible maximum concentration for the natural reservoirs. The results obtained for mutagenic activity using the Ames test were negative in all raw water samples analyzed. Positive results in XAD4 extracts of water samples were obtained for TA98 in the presence of S9 mix for two stations. Concentrations of heavy metals and nitrate can be correlated with the toxicity and genotoxicity of water analyzed. The mutagenic effect detected with TA98 strain suggested that organic compounds (after metabolization) are involved with the mutagenicity detected in the samples analyzed. The data set obtained in this work indicated the presence of at least two classes of mutagens: organic and inorganic compounds

Economy of the island of eco-tourism: the role of shark-diving and shark harvesting

Beyond its importance in maintaining ecosystems, sharks provide services that play important socioeconomic roles. The rise in their exploitation as a tourism resource in recent years has highlighted economic potential of non-destructive uses of sharks and the extent of economic losses associated to declines in their population. In this work, we present estimates for use value of sharks in Fernando de Noronha Island - the only ecotouristic site offering shark diving experience in the Atlantic coast of South America. Through the Travel Cost Method we estimate the total touristic use value aggregated to Noronha Island by the travel cost was up to USD 312 million annually, of which USD 91.1 million are transferred to the local economy. Interviewing people from five different economic sectors, we show shark-diving contribute with USD 2.5 million per year to Noronha’s economy, representing 19% of the island’s GDP. Shark-diving provides USD 128.5 thousand of income to employed islanders, USD 72.6 thousand to government in taxes and USD 5.3 thousand to fishers due to the increase in fish consumption demanded by shark divers. We discover, though, that fishers who actually are still involved in shark fishing earn more by catching sharks than selling other fish for consumption by shark divers. We conclude, however, that the non-consumptive use of sharks is most likely to benefit large number of people by generating and money flow if compared to the shark fishing, providing economic arguments to promote the conservation of these species.

Efeito do estado nutricional bioquímico de retinol e alfatocoferol sobre seus níveis em lactantes

Vitamins A and E are essential nutrients in many biological processes, so that their adequate supply to the neonate is crucial. However, the bioavailability of vitamins may be limited by factors such as maternal nutritional status and the interaction between nutrients. This study aimed to investigate the effect of biochemical nutritional status of retinol and alpha-tocopherol levels in serum and colostrum. The study included 103 healthy puerperal women treated at the reference state maternity hospital (Natal-RN). Colostrum and serum samples were collected fasting in the immediate postpartum period and the analysis of retinol and alpha-tocopherol were determined by high-performance liquid chromatography. Specific cutoff points were adopted to characterize the biochemical status of vitamins A and E. For the total group of lactanting women the average concentration of retinol in serum (1.49 ± 0.4 μmol/L-1) and colostrum (2.18 ± 0.8 μmol/L-1), as well as alpha-tocopherol in serum (26.4 ± 8.0 μmol/L-1) and colostrum (26.1 ± 12.8 μmol/L-1), indicated adequate biochemical state. However, when evaluating the individual, was found a high prevalence of deficient serum (15%) and colostrum retinol (50%), and also alphatocopherol in serum (16%) and colostrum (61%). In women with serum retinol ≥ 1.05 μmol/L-1, found an inverse correlation between serum retinol and alpha-tocopherol in colostrum (p = 0.008, r = -0.28). This association was not observed in women with serum retinol <1.05 μmol/L-1. This situation demonstrates for the first time in humans that high physiological levels of serum retinol, without supplementation, can negatively influence the transfer of alpha-tocopherol in breast milk. Although the diagnosis of satisfactory nutritional status lactanting women showed high risk of subclinical deficiency of vitamins A and E from measurements made in the colostrum

Simetria na dança: vestígios matemáticos na prática da dança esportiva em cadeira de rodas

To investigate in practice of the Wheelchair Dancesport (WDS), the mathematics of the characteristic isometric movements of the dance of ChaChaCha was the generating subject of this study. The subjects and the locus of the research were the athletes dancers of the Associação Baiana de Dança em Cadeira de Rodas (ABDCR). Referred him study aimed at to describe reflections concerning the athletes' practicing dancers of the technical acting Wheelchair Dancesport, using the inherent mathematical knowledge to the isometric movements executed in the ChaChaCha. For that, I stimulated in the athlete dancer the need to be investigating of his/her own practice, motivating him/it to be searching of information that they collaborate with his/her technical refinement, proposing like this roads to make possible his/her growth, while dancer and, also, promoting of their own movements. To reach my objectives I dialogued with some specialists to understand, to the light of their theories as, Espaçonumerática, Sociology of the mathematics, Etnomathematical, Dance and Symmetry, as those spaces they interact with the atmosphere of the Wheelchair Dancesport and that contributions could supply to the study. However, two authors of the Dancesport for walking , Ried e Laird, they brought contributions that aided in the creation of a prototype for the study of isometric movements in practice of the modality promoting the interface between the theory and the practice. The study showed to be possible to navigate still with the Mathematical Education in an universe little known as the one of the Wheelchair Dancesport. And it is in this adapts that propose a more attentive glance to the illustrations executed by the athlete dancer wheelchair and walking , in the dance of the ChaChaCha, verifying and proposing an analysis with focus investigate, looking for mathematical tracks concerning the symmetry that you/they characterize some of their illustrations