RESUMO
Estuaries are important ecosystems due to the ecological services they provide, acting as nurseries for many species of fish and invertebrates, and are also used as environments for the extraction and cultivation of mollusks. Oysters are animals that filter water to obtain oxygen and nutrients. In this process, they can bioaccumulate microorganisms and chemical substances in their tissues. The growth of mollusk culture in Northeastern Brazil requires the health identification of cultivated oysters through the quantification of the potentially harmful microbiota accumulated in the animals. Therefore, the present work aims to quantify and identify bacteria and possible pathogens found in the tissues of cultivated oysters and their culture waters. The Most Probable Number of Coliforms (MPN) in oysters and water were considered suitable according to the Brazilian current legislation, Vibrio sp. obtained low colonization and Salmonella sp. was not observed. The prevalence of microorganisms potentially pathogenic to oysters was 33.7%, highlighting metazoans and Nematopsis sp., however, the intensity of the infestation of these organisms was moderate. The low contamination of oysters demonstrates that this culture environment is promising for this activity. However, continuous environmental and sanitary monitoring is fundamental to guarantee the safety of the culture waters and the sustainability of aquaculture activities.
Assuntos
Crassostrea , Animais , Brasil , Ecossistema , Alimentos Marinhos , AquiculturaRESUMO
Estuaries are constantly subject to continuous environmental impacts of human activities, such as fisheries, port or industry, and domestic sewage, with fish being one of the most affected aquatic animals, reflecting the impacts directly on their bodies. Thus, the aim of this study was to carry out the biomonitoring of an estuary located on the Amazonian Equatorial Coast through analysis of PAHs (Polycyclic Aromatic Hydrocarbons) in the water, in addition to trace metals, histopathological alterations and analysis of erythrocyte micronuclei in Sciades herzbergii. S. herzbergii was used as a model species, due to its estuarine-resident behavior. Gonad and gill samples were subjected to histopathological evaluations. The quantification of trace metals was performed in samples of skeletal muscles of the animals collected, where concentrations of Lead (Pb), Copper (Cu), Zinc (Zn), Cadmium (Cd), Magnesium (Mg), Iron (Fe) and Aluminum (Al) were found. Except for Cadmium (Cd), all the concentrations were above the recommended limits. The PAHs analysis revealed the presence of Naphthalene and Acenaphthene in the water samples Histopathological and genotoxic analyses revealed of lesions in 100% of the study specimens. Thus, the histological and genotoxic alterations found in 100% of S. herzbergii specimens captured in São José Bay-MA are potentially associated with PAH concentrations present in the water. These results are potentially associated with the presence of PAH and trace metals, both in water and in animal tissues, inferring a general scenario of environmental contamination which directly implies a risk to the health and survival of the local biota. This study shows the relevance of continuous biomonitoring of estuarine ecosystems, in order to guide authorities regarding sewage management and ensure the evolutionary development of estuarine species, especially fishes of importance in the local cuisine, therefore related to human food security.
Assuntos
Peixes-Gato , Poluentes Ambientais , Metais Pesados , Poluentes Químicos da Água , Animais , Humanos , Cádmio , Poluentes Ambientais/análise , Ecossistema , Esgotos , Monitoramento Ambiental/métodos , Estuários , Água , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Metais Pesados/toxicidade , Metais Pesados/análiseRESUMO
BACKGROUND: Patients presenting with Barrett's esophagus (BE) should be under life-long surveillance in an attempt to detect cancer in its early stages. Esophageal capsule endoscopy (ECE) is a new technique that enables a noninvasive evaluation of the esophagus. AIMS: To evaluate ECE effectiveness compared with methylene blue (MB) chromoendoscopy for the detection of esophageal lesions in which there was suspicion of cancer, the length and pattern of BE, and the presence of hiatal hernia. MATERIAL AND METHODS: Twenty-one patients with BE who underwent Nissen fundoplication and had a follow-up period of more than five years were prospectively enrolled in the study. The patients underwent ECE and chromoendoscopy with MB performed by different physicians who were blinded to each of the procedures. RESULTS: ECE sensitivity, negative predictive value, and accuracy were 100%, 100%, and 79%, respectively, for the detection of esophageal lesions suspected of cancer. ECE accuracy in assessing BE length was 89% and in the evaluation of finger-like projections, circumferential BE, and mixed BE was 74%, 79%, and 74%, respectively. In relation to hiatal hernia detection, ECE sensitivity was 43% and its accuracy was 74%. CONCLUSIONS: ECE appears to be a good method for detecting lesions in which there is suspicion of esophageal cancer and it had modest results in regard to the accurate identification of BE length and pattern. ECE is not a good method for detecting hiatal hernia. Further studies are needed in order to define the definitive role of ECE in BE monitoring.