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Plants of the Calea genus have been reported to contain lipophilic compounds, such as sesquiterpene lactones, with cytotoxic effect against different cancer cell lines. The aim of this manuscript was to investigate the chemical profile and cytotoxic activity of different fractions from Calea phylolepis leaves on different human cancer cell lines. The fractions were prepared using solvent extraction of increasing polarity, yielding hexane, ethyl acetate and methanolic fractions. All fractions were chemically analysed by thin layer chromatography (TLC), and their cytotoxic activity against HT‐29 (colon adenocarcinoma), MCF‐7 (breast cancer), U‐251MG (malignant glioblastoma) and L929 (mouse fibroblast) cell lines was investigated. Among these, the hexane and ethyl acetate fractions showed higher cytotoxic effects, while the methanolic fraction did not show any cytotoxic effects. The major bioactive compound from the hexane fraction (12.15%) was isolated using chromatographic methods and was identified by nuclear magnetic resonance spectroscopy (NMR) and gas chromatography–mass spectrometry (GC–MS) analysis as 6‐epi‐β‐verbesinol coumarate. This compound showed activity against breast cancer cells (IC50 = 5.8 ± 1.0 μg/ml), similar to etoposide. Furthermore, 6‐epi‐β‐verbesinol coumarate showed low cytotoxicity to normal fibroblast cells, suggesting a high selectivity index (SI = 7.39) against breast cancer cells. [ABSTRACT FROM AUTHOR]

New Findings: What is the central question of this study?The aim was to compare the cost of transport and mechanical work between obese and non‐obese children at different walking speeds.What is the main finding and its importance?Our data show that the cost of transport, mechanical efficiency and work are similar and directly mass dependent in obese and non‐obese children. The optimal walking speed (most economical walking speed) is reduced in obese children. Although studies have shown the influence of gait biomechanics on the metabolic economy in obese adults and adolescents, little is known regarding obese children. We compared the metabolic cost of transport, apparent mechanical efficiency and gait biomechanics (assessed by mechanical energy fluctuations) in obese children (n = 12; mean ± SD: 8.6 ± 0.51 years of age, 1.38 ± 0.04 m, 44.6 ± 6.65 kg, 24.1 ± 3.50 kg m−2) and age‐ and sex‐matched non‐obese children (n = 12, 7.8 ± 0.90 years of age, 1.31 ± 0.08 m, 26.8 ± 2.24 kg, 16.4 ± 1.40 kg m−2) while walking at different speeds (from 1 to 5 km h−1) on a treadmill. We found that the mechanical efficiency was higher at 3 km h−1 compared with the remaining speeds for both groups (P < 0.05). Although the internal mechanical work has been greater in obese compared with non‐obese children at 4 and 5 km h−1, the external, total mechanical work and the mechanical efficiency remained similar between obese and non‐obese children at all speeds. Likewise, the cost of transport was similar in the two groups, although the optimal walking speed was an average of 0.4 km h−1 slower in obese children. Clearly, these results show that the walking economy is associated with the total mechanical work in obese and non‐obese children. Finally, the reduced functional mobility in obese children observed in previous studies seems to be associated with a reduction in optimal walking speed in comparison to non‐obese children. [ABSTRACT FROM AUTHOR]

The application of high and continuous amounts of fertilizers to the soil can cause the accumulation of pollutants and biological agents, creating environmental and health problems. The objective of this work is to evaluate the presence and mobility within a soil profile of copper and zinc residual metals from chemical and organic fertilization after successive applications in three crops. The analysis was performed using X‐ray fluorescence spectrometry. The experiment is conducted with a drainage lysimeter set. The soil used is a dystroferric Red Latosol, fertilized with chemical (nitrogen–phosphorus–potassium [NPK]) and organic (poultry litter and swine manure) fertilizers. Soil samples were collected from three points in each lysimeter at depths of 0–10, 10–20, 20–30, and 30–40 centimeters, dried in an oven, ground, and analyzed by dispersive energy X‐ray fluorescence spectrometer. The copper and zinc elements from the successive applications of chemical and organic fertilization treatment accumulated in the soil profile. The use of the dispersive energy X‐ray fluorescence spectrometer allowed the evaluation of the presence and mobility of the copper and zinc elements in the soil profile; however, the observed values do not indicate their availability. [ABSTRACT FROM AUTHOR]