Avaliação sazonal do grau de trofia em reservatórios do complexo hidrelétrico de Ribeirão das Lajes (Rio de Janeiro)

Com a demanda por energia elétrica nos dias atuais e a grande quantidade de bacias hidrográficas presentes no Brasil, a geração de energia hidrelétrica se tornou a principal forma de suprimento. Dentre as diversas mudanças ocorridas em represamento de rios, a redução na vazão da água influencia no acúmulo de nutrientes afetando diretamente na qualidade da água, podendo acarretar em um processo denominado eutrofização, caracterizado pelo aumento na quantidade de nutrientes em um sistema e contribuindo para o desenvolvimento de produtores primários (fitoplâncton e macrófitas aquáticas) em níveis acima do crescimento natural. Para identificar o estado de trofia dos reservatórios pertencentes ao Complexo Hidrelétrico de Ribeirão das Lajes (RJ) foi utilizada a metodologia de Lu e Lo (2002) de avaliação trófica fuzzy (ou difusa) sintética e não sintética, além da avaliação trófica através do índice de estado trófico de Carlson (1977). As classes de estado trófico utilizadas na metodologia é da OECD (1982) e utiliza transparência, concentrações de fósforo total e de clorofila-a como variáveis. Outras variáveis limnológicas como temperatura, oxigênio dissolvido, condutividade elétrica, turbidez, pH e sólidos dissolvidos totais foram utilizadas para caracterização dos reservatórios. As coletas foram realizadas em três momentos, no período seco de 2011, no período chuvoso de 2012 e no período seco de 2012. As análises fuzzy não sintéticas apontaram os reservatórios de Santana, Vigário e Ponte Coberta como oligotrófico/eutrófico durante o período de estudo. O reservatório de Ribeirão das Lajes foi classificado como oligotrófico nos períodos secos no ano de 2011 e 2012, e como mesotrófico no período chuvoso de 2012, assim como o reservatório de Tocos. Foram observadas diferenças significativas entre o período seco e o chuvoso em relação às concentrações de clorofila-a, transparência e turbidez, demonstrando influência sazonal no grau de trofia dos reservatórios, uma vez que clorofila-a e transparência são variáveis utilizadas em índices de estado trófico

Muscle wasting in myotonic dystrophies: a model of premature aging

Myotonic dystrophy type 1 (DM1 or Steinert's disease) and type 2 (DM2) are multisystem disorders of genetic origin. Progressive muscular weakness, atrophy and myotonia are the most prominent neuromuscular features of these diseases, while other clinical manifestations such as cardiomyopathy, insulin resistance and cataracts are also common. From a clinical perspective, most DM symptoms are interpreted as a result of an accelerated aging (cataracts, muscular weakness and atrophy, cognitive decline, metabolic dysfunction, etc.), including an increased risk of developing tumors. From this point of view, DM1 could be described as a progeroid syndrome since a notable age dependent dysfunction of all systems occurs. The underlying molecular disorder in DM1 consists of the existence of a pathological (CTG) triplet expansion in the 3' untranslated region (UTR) of the Dystrophia ll/Iyotonica Protein Kinase (DMPK) gene, whereas (CCTG)n repeats in the first intron of the Cellular Nucleic acid Binding Protein/Zinc Finger Protein 9 (CNBP/ZNF9) gene cause DM2. The expansions are transcribed into (CUG)n and (CCUG)n-containing RNA, respectively, which form secondary structures and sequester RNA binding proteins, such as the splicing factor muscleblind-like protein (MBNL), forming nuclear aggregates known as foci. Other splicing factors, such as CUGBP, are also disrupted, leading to a spliceopathy of a large number of downstream genes linked to the clinical features of these diseases. Skeletal muscle regeneration relies on muscle progenitor cells, known as satellite cells, which are activated after muscle damage, and which proliferate and differentiate to muscle cells, thus regenerating the damaged tissue. Satellite cell dysfunction seems to be a common feature of both age-dependent muscle degeneration (sarcopenia) and muscle wasting in DM and other muscle degenerative diseases. This review aims to describe the cellular, molecular and macrostructural processes involved in the muscular degeneration seen in DM patients, highlighting the similarities found with muscle aging.

Efficacy of a cognitive and behavioural psychotherapy applied by primary care psychologists in patients with mixed anxiety-depressive disorder: a research protocol

Background: In contrast with the recommendations of clinical practice guidelines, the most common treatment for anxiety and depressive disorders in primary care is pharmacological. The aim of this study is to assess the efficacy of a cognitive-behavioural psychological intervention, delivered by primary care psychologists in patients with mixed anxiety-depressive disorder compared to usual care. Methods/Design: This is an open-label, multicentre, randomized, and controlled study with two parallel groups. A random sample of 246 patients will be recruited with mild-to-moderate mixed anxiety-depressive disorder, from the target population on the lists of 41 primary care doctors. Patients will be randomly assigned to the intervention group, who will receive standardised cognitive-behavioural therapy delivered by psychologists together with usual care, or to a control group, who will receive usual care alone. The cognitive-behavioural therapy intervention is composed of eight individual 60-minute face-to face sessions conducted in eight consecutive weeks. A follow-up session will be conducted over the telephone, for reinforcement or referral as appropriate, 6 months after the intervention, as required. The primary outcome variable will be the change in scores on the Short Form-36 General Health Survey. We will also measure the change in the frequency and intensity of anxiety symptoms (State-Trait Anxiety Inventory) and depression (Beck Depression Inventory) at baseline, and 3, 6 and 12 months later. Additionally, we will collect information on the use of drugs and health care services. Discussion: The aim of this study is to assess the efficacy of a primary care-based cognitive-behavioural psychological intervention in patients with mixed anxiety-depressive disorder. The international scientific evidence has demonstrated the need for psychologists in primary care. However, given the differences between health policies and health services, it is important to test the effect of these psychological interventions in our geographical setting.

Is epizootic ulcerative syndrome (EUS) specific fungus of fishes a primary pathogen?: an opinion

Earlier findings on epizootic ulcerative syndrome (EUS) and the present observation of the authors on transmission of EUS to snakehead (Channa sp.) without skin damage provide evidence to suggest that the invasive fungus associated with EUS is a primary pathogen.

Preliminary use of oxygen stable isotopes and the 1983 El Niño to assess the accuracy of aging black rockfish (Sebastes melanops)

Black rockfish (Sebastes melanops) range from California to Alaska and are found in both nearshore and shallow continental shelf waters (Love et al., 2002). Juveniles and subadults inhabit shallow water, moving deeper as they grow. Generally, adults are found at depths shallower than 55 meters and reportedly live up to 50 years. The species is currently managed by using information from an age-structured stock assessment model (Ralston and Dick, 2003).