ABSTRACT This study demonstrates the potential for enhancing monthly streamflow forecasting in Brazil through the incorporation of climatic indices. It extends the conventional periodic autoregressive model (PAR) for streamflow forecasts by integrating climate information, represented by three key climate indices reflecting sea surface temperatures in the Pacific and Atlantic Oceans, as well as zonal wind patterns in southeastern Brazil. Using the Kling-Gupta Efficiency (KGE) skill metric, our findings reveal that the inclusion of climate data consistently outperforms existing PAR models in numerous scenarios. Notably, during May, the proposed model enhances forecasts for 79% of the reservoirs (124 out of 157), while in January, it reduces forecast variance for up to 90% of the reservoirs (141 out of 157).

RESUMO Esse estudo demonstra o potencial de aperfeiçoamento das previsões mensais de vazão ao sistema hidroelétrico brasileiro por meio da incorporação de índices climáticos. A modelagem proposta amplia o modelo periódico autoregressivo (PAR) convencional para previsões de vazão a partir da inclusão de informações climáticas, representadas por três índices climáticos-chave que refletem as temperaturas da superfície do mar nos Oceanos Pacífico e Atlântico, bem como padrões de vento zonal no sudeste do Brasil. Usando a métrica de Kling-Gupta Efficiency (KGE), os resultados obtidos revelam que a inclusão de informação climática supera consistentemente os modelos PAR existentes em inúmeras situações. Em particular, durante o mês de maio, o modelo proposto melhora as previsões para 79% dos reservatórios (124 de 157), enquanto em janeiro, reduz a variância das previsões em até 90% dos reservatórios (141 de 157).

SUMMARY Acromegaly caused by ectopic growth hormone-releasing hormone (GHRH)-secreting tumor is exceedingly rare. We report a case of acromegaly secondary to GHRH secretion by an incidentally diagnosed pulmonary neuroendocrine tumor (NET) and review 47 similar cases in literature. A 22-year-old male patient presented with symptoms of pituitary apoplexy. Magnetic resonance imaging (MRI) showed apoplexy of a pituitary adenoma. Routinely prior to surgery, a chest radiography was performed which revealed a mass in the left lung. During investigation, the patient was diagnosed with metastatic GHRH-secreting pulmonary NET. In retrospect, it was noted that the patient had pituitary hyperplasia 20 months prior to the MRI which showed the presence of a pituitary adenoma. The histological findings confirmed somatotroph hyperplasia adjacent to somatotropinoma. This case suggests that GHRH secretion can be associated with pituitary hyperplasia, which may be followed by pituitary adenoma formation.

Relata-se o caso de um paciente exposto profissionalmente a asbesto por dez anos e portador de um tumor pleural muito raro, o hemangioendotelioma epitelióde. O paciente apresentava derrame pleural serohemorrágico, sem evidência de células neoplásicas e com predomínio de linfócitos. A biópsia pleural por agulha revelou processo inflamatório crônico inespecífico, com áreas de tecido mixóide. A videotoracoscopia mostrou nódulos difusos nas pleuras parietal e visceral. A biópsia revelou neoplasia mesenquimal e eram semelhantes às áreas focais observadas na primeira biópsia. O estudo imunohistoquímico demonstrou a presença dos marcadores vasculares CD31, CD34 e Fator VIII, caracterizando a origem vascular do tumor. O paciente foi tratado com cisplatina e ectoposide, tendo o óbito ocorrido três meses após o diagnóstico.

Epithelioid hemangioendothelioma (EHE), a very uncommon pleural tumor, was diagnosed in a 61-year-old man with work-related exposure to asbestos. Serohemorrhagic pleural effusion was diagnosed in the work-up of this patient, whose complaints were chest pain and weight loss. A lymphocytic predominance was present in the effusion, but no malignant cells were seen; pleural needle biopsy disclosed only a non-specific inflammatory process. Video thoracoscopy revealed nodules in parietal and visceral pleurae. A biopsy revealed a mesenchymal neoplasm; vascular markers CD 31, CD 34 and VIII factor were present; therefore, diagnosis of HE was accepted. The tumor was not responsive to cisplatin or etoposide and the patient died 3 months after the diagnosis.