The incidence of opportunistic fungal infections in immunocompromised patients, such as those undergoing treatment with immunosuppressive drugs, intensive chemotherapy, AIDS patients and neonates, is increasing at an alarming rate. 1,2) These mycoses are very difficult to eradicate, and present an enormous challenge for healthcare providers. 3,4) The diversity of plant species in Brazil, together with their known ethnopharmacological uses, creates enormous potential for finding new structures with antifungal properties. 5,6) The Piperaceae is a vast family of plants, which has been extensively used for medicinal purposes.7) It comprises about 10 genus and approximately 2000 species, most of them herbaceous, 8) which are found mainly in tropical areas. Piper and Peperomia, the two greatest genera of the family, are well-represented in the Brazilian flora. 9)Within the Piperaceae family, the genus Piper has over 700 species, distributed throughout the tropical and subtropical regions of the world. Its phytochemistry has been object of extensive reviews. 10,11) With regard to the ethnopharmacological information, while the pungent and aromatic fruits of some species of Piper are used as spices, most of them find wide application in traditional systems of medicine 10,11) as insecticides, 7,[12][13][14] antivirals, 15,16) antimicrobials [17][18][19][20][21] and particularly antifungals. [22][23][24][25][26][27][28] These biological properties have been attributed to the presence of lignans and/or amides, such as alkyl or olefinic isobutylamides, 7,23,29) flavonoids, kawa-lactones, butenolides and cyclohexane epoxides, among others. 10)Among the different species of Piper growing in Brazil, Piper solmsianum (syn. P. leucathum or P. santosanum) known popularly as "pariparoba", is a shrub that measures 1-3 m. There are few reports on the chemical or biological studies of this plant. In contrast, phytochemical studies indicated the presence of aliphatic hydrocarbons, monoterpenes, sesquiterpenes, arylpropanoids and neolignans. [30][31][32] Recently, we have demonstrated that the fractions and some pure compounds (lignans) from the leaves of this plant exhibit significant activity against Gram-positive bacteria. 33)The current study extends our previous work on the biological properties of P. solmsianum and describes the in vitro antifungal activity of extracts, fractions and pure compounds against a panel of opportunistic pathogenic fungi using the agar dilution method. MATERIALS AND METHODS Plant MaterialPiper solmsianum C. DC. var. solmsianum (Piperaceae) was collected in May, 2001, in Ponta Grossa, State of Paraná, Brazil, and identified by Dr. Elsie Franklin Guimarães (Rio de Janeiro Botanic Museum Herbarium). A voucher specimen was deposited in the same herbarium under the number RB 368597.Phytochemical Analyses Air-dried leaves (1.36 kg) of P. solmsianum var. solmsianum were cut into small pieces and macerated at room temperature for one week in methanol. After filtration, the solvent was removed by rotary evaporat...

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Background: Aerobic exercise is recommended to improve health. However, the increased ventilation might increase the doses of inhaled air pollutants, negating the health benefits in highly polluted areas. Our objective was to estimate the inhaled dose of air pollutants during two simulated exercise sessions at cleanest and dirtiest cities reported by World Health Organization (WHO) considering air quality. Methods: Minute ventilation data were extracted from laboratory-based exercise of 116 incremental running tests and used to calculate total ventilation of a hypothetical 30-min moderate continuous exercise routine. Afterwards, total ventilation values were combined with particulate matter (PM) data reported by the WHO for the 10 cleanest and 10 dirtiest cities, to calculate inhaled doses and the relative risk of all-cause mortality by exercising in different air pollution concentrations. Findings: The dirtiest cities are located at less developed countries compared to cleanest cities. The inhaled dose of PM2.5 and PM10 were significantly higher in the dirtiest cities compared to the cleanest cities at rest and exercise, and significantly higher during exercise compared to the rest at dirtiest cities. The relative risk of all-cause mortality analysis showed that, while exercise in the cleanest cities improved health benefits throughout up to 90 min, there were no further health benefits after 15 min of exercise in the dirtiest cities, and the air pollution health risks surpassed the exercise benefits after 75 min. Interpretation: Our findings suggest that a traditional 30-min of moderate aerobic exercise session might induce inhalation of high levels of pollutants when performed at dirtiest cities. Considering several adverse health effects from air pollutants inhalation, so the results suggest that the air pollution levels of the cities should be taken into account for physical exercise recommendations.

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Pacing during a high-intensity cycling time trial (TT) appears to prevent premature task failure, but the performance fatigability during a self-paced exercise is currently unknown. Therefore, the current study characterized the time course of performance fatigability during a 4-km TT. Eleven male cyclists performed three separated TTs in a crossover, counterbalanced design. The TTs lasted until the end of the fast-start (FS; 600 ± 205 m), even-pace (EP; 3,600 ± 190 m), and end-spurt (ES; 4,000 m) phases. Performance fatigability was characterized by using isometric maximal voluntary contractions (IMVCs), whereas the muscle activation [i.e., voluntary activation (VA)] and contractile function of knee extensors [e.g., peak torque of potentiated twitches (TwPt)] were evaluated using electrically evoked contractions performed before and 1 min after each specific part of the trial. Gas exchange, power output (PO), and electromyographic activity (EMG) were also recorded. EMG/PO showed an abrupt increase followed by a continuous decrease toward the end of FS, resulting in a drop in IMVC (−12%), VA (−8%), and TwPt (−23%). EMG/PO was stable during EP, with no additional drop on IMVC, VA, or TwPt (−12%, −6%, and −22%, respectively). EMG/PO increased abruptly during the ES, but there was no change in IMVCs, VA, or TwPt (−13%, −8%, and −26%, respectively). These findings demonstrate that the performance fatigability during a self-paced exercise is characterized by a large drop in contractile function and muscle activation at the beginning of the trial (i.e., FS), without additional change during the middle and end phases (i.e., EP and ES). NEW & NOTEWORTHY The time course of performance fatigability throughout a self-paced exercise is currently unknown. The results showed that a large amount of muscle activation and contractile function impairments are attained early on a self-paced exercise (first ∼15% of the total time trial distance) and maintained throughout the test. This novel finding characterizes the performance fatigability from a contractile function and muscle activation perspective, which brings new insights for future studies focused on real-world exercise training and competition.