Browsing by Issue Date, starting with "2023-01-04"
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- First approach to assess the effects of nanoplastics on the soil species Folsomia candida: A mixture design with bisphenol A and diphenhydraminePublication . Barreto, Ângela; Santos, Joana; Almeida, Lara; Tavares, Vítor; Pinto, Edgar; Celeiro, Maria; Garcia-Jares, Carmen; Maria, Vera L.The terrestrial environment is one of the main recipients of plastic waste. However, limited research has been performed on soil contamination by plastics and even less assessing the effects of nanoplastics (NPls). Behind the potential toxicity caused per se, NPls are recognized vectors of other environmental harmful contaminants. Therefore, the main aim of the present study is to understand whether the toxicity of an industrial chemical (bisphenol A – BPA) and a pharmaceutical (diphenhydramine – DPH) changes in the presence of polystyrene NPls to the terrestrial invertebrate Folsomia candida. Assessed endpoints encompassed organismal (reproduction, survival and behavior) and biochemical (neurotransmission and oxidative stress) levels. BPA or DPH, 28 d single exposures (1 to 2000 mg/kg), induce no effect on organisms' survival. In terms of reproduction, the calculated EC50 (concentration that causes 50% of the effect) and determined LOEC (lowest observed effect concentration) were higher than the environmental concentrations, showing that BPA or DPH single exposure may pose no threat to the terrestrial invertebrates. Survival and reproduction effects of BPA or DPH were independent on the presence of NPls. However, for avoidance behavior (48 h exposure), the effects of the tested mixtures (BPA + NPls and DPH + NPls) were dependent on the NPls concentration (at 0.015 mg/kg – interaction: no avoidance; at 600 mg/kg – no interaction: avoidance). Glutathione S-transferase activity increased after 28 d exposure to 100 mg/kg DPH + 0.015 mg/kg NPls (synergism). The increase of lipid peroxidation levels found after the exposure to 0.015 mg/kg NPls (a predicted environmental concentration) was not detected in the mixtures (antagonism). The results showed that the effects of the binary mixtures were dependent on the assessed endpoint and the tested concentrations. The findings of the present study show the ability of NPls to alter the effects of compounds with different natures and mechanisms of toxicity towards soil organisms, showing the importance of environmental risk assessment considering mixtures of contaminants.
- Comparison of the portuguese version of the Pregnancy Physical Activity Questionnaire (PPAQ) with accelerometry for classifying physical activity among pregnant women with obesityPublication . Bernardo, Diana; Carvalho, Carlos; Leirós-Rodríguez, Raquel; Mota, Jorge; Santos, Paula ClaraIn recent years, the number of pregnant women with obesity has increased exponentially; thus, it is important to evaluate and characterize the physical activity levels of this specific group. The aim of this study is to evaluate the reliability and validity of the Portuguese version of the Physical Activity and Pregnancy Questionnaire and Pregnancy Questionnaire in pregnant women with obesity and to classify physical activity using the Physical Activity and Pregnancy Questionnaire and accelerometry. An analytical observational study was carried out between May and August of 2019 at the University Hospital Center of São João, with a sample of 31 pregnant women with obesity (30.9 ± 4.6 years 36.5 ± 4.6 kg/m2 of BMI and 21.5 ± 9 gestational weeks). The physical activity of participants was evaluated using an accelerometer and Physical Activity and Pregnancy Questionnaire at two time points (the first visit at the moment of consultation and the second seven days after, with accelerometer retest), the interclass correlation coefficient was used to test reliability between the Physical Activity and Pregnancy Questionnaire filled out at visit1 and the Physical Activity and Pregnancy Questionnaire filled out at visit2, and Pearson’s correlation was used to determine validity between the Physical Activity and Pregnancy Questionnaire and accelerometry. The interclass correlation coefficient values for total activity were 0.95, 0.97 for moderate and 0.58 for vigorous intensities. It ranged from 0.74 for sports/exercise to 0.96 for domestic activities. The Pearson’s correlations showed that the Physical Activity and Pregnancy Questionnaire is moderately valid for moderate intensity (r = 0.435). A total of 67.7% of the pregnant women complied with international physical activity recommendations.