Sara Rodrigues

Short-term effects of neuroactive pharmaceutical drugs on a fish species: Biochemical and behavioural effects

The presence of pharmaceutical residues in the aquatic environment is receiving great attention since significant levels of contamination have been found, not only in sewage treatment plant effluents, but also in open waters. In our study, the toxicity of three anticonvulsant drugs commonly found in the environment (diazepam, carbamazepine, and phenytoin) was evaluated in Lepomis gibbosus (pumpkinseed sunfish). This study focused on oxidative stress parameters, namely: glutathione reductase (GRed), glutathione S-transferases (GSTs), catalase (CAT), and lipid peroxidation (thiobarbituric acid reactive substances, TBARS) in the hepatic, digestive, and gill tissues of exposed animals. Simultaneously, we assessed the effects of these drugs in terms of behavioural parameters, such as scototaxis and activity. Exposure to diazepam caused an increase in GST activities in the gills and an inhibition of GRed in the digestive tract, relative to control, suggesting an antioxidant response. It also caused fish to spend more time swimming and less time in a refuge area (black compartment of an aquarium). Exposure to carbamazepine caused an increase in GSTs and GRed activity in the digestive tract, which is not always consistent with the literature. A significant positive correlation was found between carbamazepine concentration and time spent in motion and a negative correlation with time spent in black compartment. Exposure to phenytoin was responsible for adaptive responses in the activities of CAT and GSTs (in the liver), but it did not elicit any behavioural alterations. Although all three drugs seemed to induce oxidative stress in some organs, peroxidative damage (measured as TBARS concentrations) was not found at the selected range of concentrations. Our results enlighten the need for more research on the ecological consequences of pharmaceuticals in the aquatic environment, especially drugs that interfere with the CNS and behaviour, because the net outcome of these effects may be difficult to predict.

Portuguese households' diet quality (adherence to Mediterranean food pattern and compliance with WHO population dietary goals): trends, regional disparities and socioeconomic determinants.

Objective:To evaluate households’ diet-quality trends and regional disparities, as well as to identify the influence of its socioeconomic determinants.Methods/Subjects:Two dietary indexes were applied: a revised Healthy Diet Indicator version (HDIr) and the Mediterranean Adequacy Index (MAI). The socioeconomic differences between households with low-diet quality (if their scoring in HDIr or MAI was below the national median) and the remaining ones were analysed by means of logistic regression. Representative samples of households among each region were analysed.Results:Adherence to a Mediterranean diet was poor in all Portuguese regions; the proportion of households adhering to it has diminished in the North, Centre, Lisbon and Tejo valley. The proportion of households with high HDIr decreased in the North, Centre, Lisbon and Tejo valley and Algarve. In multivariate analysis, households whose head had secondary or higher education, living in semi-urban or urban areas, from the Azores region, within the higher income or outside home food expenditures groups were more likely to be in low-quality diet.Conclusions:The decreasing adherence to a Mediterranean food pattern and the diminishing compliance with World Health Organization dietary goals show that Portuguese households have reduced their diet quality. The observed influence of urbanization and region on diet quality highlights the importance of considering regional nutrition strategies.

Food balance sheet and household budget survey dietary data and mortality patterns in Europe.

Worldwide dietary data for nutrition monitoring and surveillance are commonly derived from food balance sheets (FBS) and household budget surveys (HBS). We have compared food supply from FBS and food availability data from HBS among eighteen European countries and have estimated the extent to which they correlate, focusing on food groups which are comparably captured by FBS and HBS and for which there is epidemiological evidence that they can have a noticeable impact on population mortality. Spearmans correlation coefficient was +0.78 (P < 10- 3) for vegetables (including legumes),+0.76 (P < 10- 3) for fruits, +0.69 (P < 10- 3) for fish and seafood and +0.93 (P < 10- 3) for olive oil. With respect to meat and meat products, the coefficient was lower at +0.39 (P = 0.08). Moreover, we have examined whether the supply (FBS) or the availability (HBS) of food groups known or presumed to have beneficial effect on the occurrence of CHD and total cancer can predict overall, coronary and cancer mortality in ecological analyses. After controlling for purchasing power parity-adjusted gross domestic product and tobacco smoking we found that for vegetables, fruits, fish and seafood, as well as for olive oil, both the FBS and the HBS estimates were inversely associated with all three indicators of mortality, although the number of countries with complete information on all study variables hindered formal statistical documentation (P>0.05 in some instances). FBS and HBS have their own strengths and weaknesses, but they may complement each other in dietary assessments at the population level.

Determination of plate waste in primary school lunches by weighing and visual estimation methods: A validation study

The aim of this study was to validate the visual estimation method for aggregated plate waste of main dish at Portuguese primary school canteens. For this purpose plate waste at school lunch was measured for 505 individual servings, using weighing individual servings and plate waste and visual estimation method by a 6-point scale, as developed by Comstock et al. (1981). A high variability of initial serving weights was found with serving sizes ranging from 88.9 to 283.3g and with a coefficient of variation ranging from 5.5% to 24.7%. Mean plate waste was 27.5% according to the weighing method. There was a significant bias in the conversion of the visual waste estimations to actual waste, being overestimated by an average of 8.0 g (ranging from -12.9 g to 41.4 g). According to Bland and Altman plot, the mean difference between methods was of 8.0 g and the amplitude interval was 102.6g. The study showed that the visual estimation method is not as accurate as the weighing method in assessing nonselective aggregated plate waste at primary school canteens. Our findings are thus very important on considering plate waste assessment, since the wide variation on initial servings introduces a relevant bias when considering standard portions or a random sample of initial servings. Although, greater convenience, time-saving and the possibility to monitor plate waste of large groups, make the visual estimation method an important method to assess plate waste at school canteens, these results highlighted the need of portions standardization and control of initial servings to allow for its use.

Comparison of national food supply, household food availability and individual food consumption data in Portugal

The present study aimed to compare Portuguese food and nutrient data retrieved from three distinct sources of dietary data: national food supply, household food availability and individual food consumption. In particular it was intended to validate the use of the dietary data derived from the Portuguese household budget surveys (HBS). The data sources used were food balance sheets (FBS) (1990, 1995 and 2000) generated by the Food and Agriculture Organization (FAO), HBS (1990, 1995 and 2000) collected by the National Statistics Institute (INE) and individual consumption obtained through a food frequency questionnaire (FFQ) applied in the context of the EpiPorto study circa 2000. Thirteen comparable food groups were established for analysis. Total energy, macronutrients and other selected dietary components were considered. The average daily values of different dietary sources were compared in absolute amounts (g/person per day) and in relative energy contribution (%E). To evaluate association and agreement between sources, Spearman’s correlation coefficients and distance matrices based on Euclidian distances were computed. The obtained average daily per capita amounts reflect the different points of data collection in the food chain; HBS fall in the expected position, below FBS and closer to FFQ. Agreement between FBS, HBS and FFQ was higher when data were expressed in relative energy contribution than when absolute amounts were considered. In general, the observed discrepancies between the three data sources could be attributed to known differences in the methodological approaches. This study supports the finding that despite their constraints the HBS-derived data are a valid option to evaluate dietary habits in Portugal.

Acute and chronic effects of erythromycin exposure on oxidative stress and genotoxicity parameters of Oncorhynchus mykiss

Erythromycin (ERY) is a macrolide antibiotic used in human and veterinary medicine, and has been detected in various aquatic compartments. Recent studies have indicated that this compound can exert biological activity on non-target organisms environmentally exposed. The present study aimed to assess the toxic effects of ERY in Oncorhynchus mykiss after acute and chronic exposures. The here adopted strategy involved exposure to three levels of ERY, the first being similar to concentrations reported to occur in the wild, thus ecologically relevant. Catalase (CAT), total glutathione peroxidase (GPx), glutathione reductase (GRed) activities and lipid peroxidation (TBARS levels) were quantified as oxidative stress biomarkers in gills and liver. Genotoxic endpoints, reflecting different types of genetic damage in blood cells, were also determined, by performing analysis of genetic damage (determination of the genetic damage index, GDI, measured by comet assay) and of erythrocytic nuclear abnormalities (ENAs). The results suggest the occurrence of a mild, but significant, oxidative stress scenario in gills. For acutely exposed organisms, significant alterations were observed in CAT and GRed activities, and also in TBARS levels, which however are modifications with uncertain biological interpretation, despite indicating involvement of an oxidative effect and response. After chronic exposure, a significant decrease of CAT activity, increase of GPx activity and TBARS levels in gills was noticed. In liver, significant decrease in TBARS levels were observed in both exposures. Comet and ENAs assays indicated significant increases on genotoxic damage of O. mykiss, after erythromycin exposures. This set of data (acute and chronic) suggests that erythromycin has the potential to induce DNA strand breaks in blood cells, and demonstrate the induction of chromosome breakage and/or segregational abnormalities. Overall results indicate that both DNA damaging effects induced by erythromycin may be related to the oxidative damage observed, shown to occur at environmentally relevant concentrations of erythromycin.

Eating out is different from eating at home among individuals who occasionally eat out. A cross-sectional study among middle-aged adults from eleven European countries

Eating out has been linked to the current obesity epidemic, but the evaluation of the extent to which out of home (OH) dietary intakes are different from those at home (AH) is limited. Data collected among 8849 men and 14,277 women aged 35-64 years from the general population of eleven European countries through 24-h dietary recalls or food diaries were analysed to: (1) compare food consumption OH to those AH; (2) describe the characteristics of substantial OH eaters, defined as those who consumed 25 % or more of their total daily energy intake at OH locations. Logistic regression models were fit to identify personal characteristics associated with eating out. In both sexes, beverages, sugar, desserts, sweet and savoury bakery products were consumed more OH than AH. In some countries, men reported higher intakes of fish OH than AH. Overall, substantial OH eating was more common among men, the younger and the more educated participants, but was weakly associated with total energy intake. The substantial OH eaters reported similar dietary intakes OH and AH. Individuals who were not identified as substantial OH eaters reported consuming proportionally higher quantities of sweet and savoury bakery products, soft drinks, juices and other non-alcoholic beverages OH than AH. The OH intakes were different from the AH ones, only among individuals who reported a relatively small contribution of OH eating to their daily intakes and this may partly explain the inconsistent findings relating eating out to the current obesity epidemic.

Afterload-induced diastolic dysfunction contributes to high filling pressures in experimental heart failure with preserved ejection fraction.

Myocardial stiffness and upward-shifted end-diastolic pressure-volume (P-V) relationship (EDPVR) are the key to high filling pressures in heart failure with preserved ejection fraction (HFpEF). Nevertheless, many patients may remain asymptomatic unless hemodynamic stress is imposed on the myocardium. Whether delayed relaxation induced by pressure challenge may contribute to high end-diastolic pressure (EDP) remains unsettled. Our aim was to assess the effect of suddenly imposed isovolumic afterload on relaxation and EDP, exploiting a highly controlled P-V experimental evaluation setup in the ZSF1 obese rat (ZSF1 Ob) model of HFpEF. Twenty-week-old ZSF1 Ob (n = 12), healthy Wistar-Kyoto rats (WKY, n = 11), and hypertensive ZSF1 lean control rats (ZSF1 Ln, n = 10) underwent open-thorax left ventricular (LV) P-V hemodynamic evaluation under anesthesia with sevoflurane. EDPVR was obtained by inferior vena cava occlusions to assess LV ED chamber stiffness constant β, and single-beat isovolumic afterload acquisitions were obtained by swift occlusions of the ascending aorta. ZSF1 Ob showed increased ED stiffness, delayed relaxation, as assessed by time constant of isovolumic relaxation (τ), and elevated EDP with normal ejection fraction. Isovolumic afterload increased EDP without concomitant changes in ED volume or heart rate. In isovolumic beats, relaxation was delayed to the extent that time for complete relaxation as predicted by 3.5 × monoexponentially derived τ (τexp) exceeded effective filling time. EDP elevation correlated with reduced time available to relax, which was the only independent predictor of EDP rise in multiple linear regression. Our results suggest that delayed relaxation during pressure challenge is an important contributor to lung congestion and effort intolerance in HFpEF.

Rainbow trout (Oncorhynchus mykiss) pro-oxidant and genotoxic responses following acute and chronic exposure to the antibiotic oxytetracycline

Oxytetracycline (OTC), an antibacterial agent, is extensively used in aquaculture practices all over the world, but also in human and veterinary medicines. Because of its intensive use, low rates of absorption by treated animals, inadequate disposal, and low efficiency of removal in wastewater treatment plants, the potential harmful effects on aquatic organisms are of great concern. This work aimed to assess the effects of this antibiotic in rainbow trout, following both acute and chronic exposures. Catalase (CAT), total glutathione peroxidase (GPx), glutathione reductase (GRed) activities and lipid peroxidation (TBARS levels) were quantified as oxidative stress biomarkers, in gills and liver. Genotoxic endpoints, reflecting different types of genetic damage in blood cells, were also determined, by analysis of genetic damage (determination of the genetic damage index, GDI, measured by comet assay) and erythrocytic nuclear abnormalities (ENAs). The obtained results showed a mild pattern of antioxidant response, with modifications in CAT and GPx activities in gills, and lipid peroxidation in liver. These results suggest that despite the occurrence of oxidative effects, a full scenario of oxidative stress is not likely. However, exposure to OTC resulted in the establishment of genotoxic alterations with the induction of DNA strand breaks in blood cells (increase of GDI), and of chromosome breakage and/or segregational abnormalities (increase of ENAs). Considering that the oxidative response was not totally devisable, other mechanisms may be involved in the genotoxic effects reported.

Effects of chronic exposure to benzalkonium chloride in Oncorhynchus mykiss: cholinergic neurotoxicity, oxidative stress, peroxidative damage and genotoxicity

Benzalkonium chloride (BAC) is one of the most used conservatives in pharmaceutical preparations. However, its use is limited to a small set of external use formulations, due to its high toxicity. Benzalkonium chloride effects are related to the potential exertion of deleterious effects, mediated via oxidative stress and through interaction with membrane enzymes, leading to cellular damage. To address the ecotoxicity of this specific compound rainbow trouts were chronically exposed to BAC at environmental relevant concentrations (ranging from 0.100 to 1.050mg/L), and the biological response of cholinergic neurotoxicity, modulation of the antioxidant defense, phase II metabolism, lipid peroxidation and genotoxicity was studied. The obtained results showed a dual pattern of antioxidant response, with significant alterations in catalase activity (starting at 0.180mg/L), and lipid peroxidation, for intermediate (0.180 and 0.324mg/L) concentrations. No significant alterations occurred for glutathione-S-transferases activity. An unexpected increased of the acetylcholinesterase activity was also recorded for the individuals exposed to higher concentrations of BAC (starting at 0.180mg/L). Furthermore, exposure to BAC resulted in the establishment of genotoxic alterations, observable (for the specific case of the comet assay results) for all tested BAC concentrations. However, and considering that the oxidative response was not devisable, other mechanisms may be involved in the genotoxic effects reported here.