Resumo A qualidade das águas é caracterizada por parâmetros físicos, químicos e microbiológicos, os quais são submetidos constantemente a interferências de ordem natural, do próprio ecossistema, e de ordem antrópica, advindas das atividades de uso e ocupação do solo. No Estado do Rio Grande do Norte, Brasil, a melhoria da qualidade das águas exige atenção, tendo em vista que a região perde parte significativa de suas águas pelas altas taxas de evaporação. A cidade de Portalegre apresenta um conjunto paisagístico formado por nascentes perenes, brejos de altitude e cachoeiras. Considerando as características do local, este trabalho caracterizou a qualidade hídrica do Riacho da Bica que percorre a área de microbacia que se encontra na vertente norte do município e é bastante procurado para fins de recreação de contato primário. O objetivo da pesquisa foi a análise do Índice de Qualidade das Águas (IQA) em três pontos do Riacho da Bica e a análise da balneabilidade na Cachoeira do Pinga, frequentemente usada por banhistas. Os resultados mostram que a qualidade das águas é melhor na nascente do Riacho da Bica em que o IQA foi classificado como "regular". Os demais pontos do riacho foram classificados como "ruim". A balneabilidade das águas da Cachoeira do Pinga foi classificada como excelente.

Abstract Water quality is characterized by physical, chemical and microbiological parameters, which are constantly subject to the interference of nature, the ecosystem and human land-use activities. In Rio Grande do Norte State, Brazil, the improvement of water quality requires attention, considering that the region loses a significant portion of its waters through high evaporation rates. In this context, the town of Portalegre has a complex landscape formed by perennial springs, upper swamps and waterfalls. Considering the uniqueness of the area, this research characterized the water quality of Bica Stream, which flows through the watershed area located on the north side of the city, and is very popular for leisure activities. This research analyzed the Water Quality Index (WQI) at three points of the Bica Stream, as well as the Pinga Waterfall's suitability for bathing, as it is frequently used for this purpose. The results show that the water quality is better at the spring of Bica Stream, with a WQI classified as "regular". The other parts of the stream were classified as "bad". The waterfall water was classified as excellent for bathing.

INTRODUCTION: Bipolar disorder (BD) is a prevalent, chronic and progressive illness. There is a growing body of evidence indicating that brain-derived neurotrophic factor (BDNF) plays an important role in the pathophysiology of BD. OBJECTIVE: The aim of this study was to evaluate BDNF plasma levels in BD patients with long term illness in comparison with controls. METHODS: 87 BD type I patients and 58 controls matched by age, gender and education level were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatric Interview and the patients by the Young Mania Rating Scale and the Hamilton Depression Rating Scale. The plasma levels of BDNF were measured by ELISA. RESULTS: On average, patients had suffered from BD for 23.4 years. In comparison with controls, BD patients with mania presented a 1.90-fold increase in BDNF plasma levels (p = .001), while BD patients in remission presented a 1.64-fold increase in BDNF plasma levels (p = .03). BDNF plasma levels were not influenced by age, length of illness or current medications. CONCLUSIONS: The present study suggests that long-term BD patients exhibit increased circulating levels of BDNF.