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Nota: These guidelines are for information purposes and should not replace the clinical judgment of a physician, who must ultimately determine the appropriate treatment for each patient.

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Alcoholic fermentation of cheese whey permeate was investigated using a recombinant flocculating Saccharomyces cerevisiae, expressing the LAC4 (coding for beta-galactosidase) and LAC12 (coding for lactose permease) genes of Kluyveromyces marxianus enabling for lactose metabolization. Data on yeast fermentation and growth on cheese whey permeate from a Portuguese dairy industry is presented. For cheese whey permeate having a lactose concentration of 50 gL(-1), total lactose consumption was observed with a conversion yield of ethanol close to the expected theoretical value. Using a continuously operating 5.5-L bioreactor, ethanol productivity near 10 g L(-1) h(-1) (corresponding to 0.45 h(-1) dilution rate) was obtained, which raises new perspectives for the economic feasibility of whey alcoholic fermentation. The use of 2-times concentrated cheese whey permeate, corresponding to 100 gL(-1) of lactose concentration, was also considered allowing for obtaining a fermentation product with 5% (w/v) alcohol.

The present study investigated whether the practice of exercise has a protective effect against cardiac toxicity induced by doxorubicin (DOX). A systematic review of randomized clinical trials evaluating the role of exercise in the control or prevention of DOX-induced cardiotoxicity was performed in MEDLINE and LILACS databases. Studies that did not address the main subject of this review, did not mention physical exercise or DOX, studies that evaluated other types of anthracycline-induced toxicities only (muscle, hepatic and renal toxicity) or other effects of exercise on DOX toxicity (fatigue) were excluded. With respect to the variables related to aerobic exercise prescription, there was no direct relationship between the frequency of exercise and the results of the studies. Also, intensity of exercise was not decisive for preservation of cardiac function, although a more intense exercise was associated with improvements in the antioxidant system, which was not observed in studies on lower intensity exercises. No significant differences in exercise effects were observed when it was performed before, during or after the treatment. Therefore, aerobic exercise may exert a protective effect of cardiac functions when performed before, during or after treatment with DOX. However, the mechanisms of this effect are still unknown.

★★★★ Palavras-chave: Depressão. Medicina do Exercício e do Esporte. Psicologia do Esporte.INTRODUÇÃO: Segundo as estimativas, utilizando a metodologia da Carga Global da Doença, proposta pela Organização Mundial de Saúde, para o ano de 2020, a doença isquêmica do coração e a depressão serão as duas maiores causas não só de mortalidade mas, de incapacidade sobre a população em geral. A depressão é caracterizada por tristeza, baixa da auto-estima, pessimismo, pensamentos negativos recorrentes, desesperança e desespero. Seus sintomas são, fadiga, irritabilidade, retraimento e ideação suicida. O humor depressivo pode aparecer como uma resposta a situações reais, por meio de uma reação vivencial depressiva, quando diante de fatos desagradáveis, aborrecedores, frustrações e perdas.Trata-se, neste caso, de uma resposta a conflitos íntimos e determinados por fatores vivenciais. A depressão está associada a uma alta incapacidade e perda social. Muitos estudos apontam à possibilidade de pessoas fisicamente ativas, em qualquer idade, apresentarem uma melhor saúde mental do que sedentários. Entre as hipoteses que tentam explicar a ação dos exercícios sobre a ansiedade e depressão, uma das mais aceita é a hipótese das Endorfinas. A teoria da endorfina sugere que a atividade física desencadearia uma secreção de endorfinas capaz de provocar um estado de euforia natural, por isso, aliviando os sintomas da depressão. Essa idéia, entretanto, não tem consenso entre os pesquisadores. Alguns deles, por exemplo, preferem acreditar que o exercício físico regularia a neurotransmissão da noradrenalina e da serotonina, igualmente aliviando os sintomas da depressão. Outra hipótese seria a cognitiva. De natureza eminentemente psicológica, a hipó-tese cognitiva se fundamenta na melhoria da autoestima mediante a prática do exercício, sustentando que os exercícios em longos prazos ou os exercícios intensivos melhorariam a imagem de si mesmo e, conseqüentemente, a autoestima.

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Synergism among reflexes probably contributes to exercise hyperventilation in patients with heart failure with reduced ejection fraction (HFrEF). Thus, we investigated whether the carotid chemoreflex and the muscle metaboreflex interact to the regulation of ventilation (normalV˙E) in HFrEF. Ten patients accomplished 4‐min cycling at 60% peak workload and then recovered for 2 min under either: (a) 21% O2 inhalation (tonic carotid chemoreflex activity) with legs’ circulation free (inactive muscle metaboreflex); (b) 100% O2 inhalation (suppressed carotid chemoreflex activity) with legs’ circulation occluded (muscle metaboreflex activation); (c) 21% O2 inhalation (tonic carotid chemoreflex activity) with legs’ circulation occluded (muscle metaboreflex activation); or (d) 100% O2 inhalation (suppressed carotid chemoreflex activity) with legs’ circulation free (inactive muscle metaboreflex) as control. normalV˙E, tidal volume (VT) and respiratory frequency (fR) were similar between each separated reflex (protocols a and b) and control (protocol d). Calculated sum of separated reflexes effects was similar to control. Oppositely, normalV˙E (mean ± SEM: Δ vs. control = 2.46 ± 1.07 L/min, p = .05) and fR (Δ = 2.47 ± 0.77 cycles/min, p = .02) increased versus control when both reflexes were simultaneously active (protocol c). Therefore, the carotid chemoreflex and the muscle metaboreflex interacted to normalV˙E regulation in a fR‐dependent manner in patients with HFrEF. If this interaction operates during exercise, it can have some contribution to the HFrEF exercise hyperventilation.