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1.
Sci Total Environ ; 912: 169287, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38103621

RESUMEN

The application of bio-based biodegradable mulch films in agriculture has raised environmental concerns regarding their potential impacts on adjacent freshwater ecosystems. This study investigated the biodegradation of microplastics derived from a bio-based biodegradable mulch (bio-MPs) and its acute and chronic ecotoxicity considering relevant scenarios (up to 200 and 250 mg/kg of sediment, using pristine and/or UV-aged particles), using the fungus Penicillium brevicompactum and the dipteran Chironomus riparius as model organisms, respectively, due to their ecological relevance in freshwater environments. Fourier-transform infrared spectroscopy analysis suggested changes in the fungus's carbohydrate reserves and bio-MP degradation through the appearance of low molecular weight esters throughout a 28 day biodegradation test. In a short-term exposure (48 h), C. riparius larvae exposed to pristine or UV-aged bio-MPs had up to 2 particles in their gut. Exposure to pristine bio-MPs decreased larval aerobic metabolism (<20 %) and increased neurotransmission (>15 %), whereas exposure to UV-aged bio-MPs activated larval aerobic metabolism (>20 %) and increased antioxidant defences (catalase activity by >30 % and glutathione-s-transferase by >20 %) and neurotransmission (>30 %). Longer-term (28-d) exposure to UV-aged bio-MPs did not affect larval survival and growth nor the dipteran's emergence but increased male numbers (>30 %) at higher concentrations. This study suggests that the selected agricultural bio-based mulch film is prone to biodegradation by a naturally occurring fungus. However, there is a potential for endocrine disruption in the case of prolonged exposures to UV-aged microplastics. This study emphasises the importance of further research to elucidate the potential ecological effects of these plastic products, to ensure effective management practices, and to establish new regulations governing their use.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Masculino , Microplásticos/toxicidad , Plásticos/toxicidad , Ecosistema , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Agricultura , Larva , Agua Dulce
2.
Obes Surg ; 33(12): 3938-3943, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37880463

RESUMEN

BACKGROUND: The behavior of patients undergoing metabolic bariatric surgery (MBS) has been widely investigated to better understand their attitudes and to formulate effective advisory strategies. Although these elements have been studied separately, the magnitude of these behaviors still needs to be determined from a combined factors approach. This study aimed to identify the lifestyle patterns of patients who underwent MBS 5 or more years ago. METHODS: In this observational study, 123 patients who underwent MBS at least 5 years ago were included. Anthropometric data, sociodemographic profile, dietary intake, physical activity level, sleeping, smoking, and alcohol consumption were collected for all participants. Lifestyle pattern was evaluated using principal component analysis (PCA) and the Kaiser-Meyer-Olkin (KMO) index was applied to evaluate data factorability. RESULTS: PCA identified two patterns of behavior adopted by the participants in the late postoperative (PO) period (more than 5 years PO) of MBS. In the first pattern, a positive correlation was found between consumption of ultra-processed foods (r = 0.459), risky consumption of alcoholic beverages (r = 0.630), and tobacco use (r = 0.584). In the second, a positive correlation was observed between the consumption of unprocessed or minimally processed foods (r = 0.692) and more sleep time per day (r = 0.654). CONCLUSION: After 5 years of PO, combined behavior analysis revealed healthy and unhealthy lifestyle patterns, which points to the relevance of permanent clinical follow-up of these patients to ensure the best health status.


Asunto(s)
Cirugía Bariátrica , Obesidad Mórbida , Humanos , Obesidad Mórbida/cirugía , Estilo de Vida , Ingestión de Alimentos , Periodo Posoperatorio , Conducta Alimentaria
3.
Sci Total Environ ; 875: 162556, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36870489

RESUMEN

Freshwater benthic environments are among the major sinks of microplastics (MPs, < 5 mm) sourced on inland anthropogenic activities. The ecotoxicological effects of MPs on benthic macroinvertebrates have been assessed preferably in collectors, shredders, and filter-feeders, but resulting in insufficient knowledge on the potential trophic transfer and its effects on macroinvertebrates with predator behaviour such as planarians. This work evaluated the behavioural (feeding, locomotion), physiological (regeneration) and biochemical responses (aerobic metabolism, energy reserves, oxidative damage) of the planarian Girardia tigrina after consuming contaminated live prey Chironomus riparius larvae previously exposed to microplastics of polyurethane (PU-MPs; 7-9 µm in size; 375 mg PU-MPs/kg). After the feeding period (3 h), planarians consumed 20 % more contaminated prey than uncontaminated prey, probably related to increased curling/uncurling movements of larvae (that might be more appellative to planarians). Histological analysis revealed planarians' limited intake of PU-MPs, mainly detected near the pharynx. The consumption of contaminated prey (and intake of PU-MPs) did not result in oxidative damage but slightly increased the aerobic metabolism and energy reserves which show that the consumption of more prey was sufficient to cope with the potential adverse effects of internalized MPs. Moreover, no effects were observed in the locomotion of planarians in good agreement with the hypothesis of sufficient energy acquired by the exposed planarians. Despite the previous, it seems that the energy acquired was not allocated for planarians' regeneration since a significant delay in the regeneration of the auricles was observed for planarians feeding on contaminated prey. Therefore, further studies should be performed considering the potential long-term effects (i.e., reproduction/fitness) and the effects of MPs that might result from continuous feeding on contaminated prey, representing a more realistic exposure scenario.


Asunto(s)
Planarias , Contaminantes Químicos del Agua , Animales , Microplásticos , Plásticos , Planarias/fisiología , Contaminantes Químicos del Agua/toxicidad , Agua Dulce
4.
Artículo en Inglés | MEDLINE | ID: mdl-36497682

RESUMEN

Freshwater provides valuable services and functions to humankind. However, macroinvertebrates that underpin the delivery of many of those ecosystem services and functions are under an additional threat caused by microplastic pollution. Chironomids are one of the most abundant groups of macroinvertebrates in these environments and the most sensitive to microplastics. This investigation addressed the effects of polyurethane (PU-MPs; 7.0-9.0 µm) on the chironomid Chironomus riparius at the organism and sub-organism levels. For this purpose, two assays were carried out: (i) addressing the effects of PU-MPs on C. riparius partial life cycle traits (larval size and emergence parameters) in a 28 d assay considering concentrations up to 750 mg/Kg, and (ii) larvae behaviour (locomotion) as well as the biochemical responses (oxidative damage, aerobic energy production, and energy reserves) in a 10 d assay considering an environmentally relevant concentration with no observed effects on C. riparius previous life history traits (no observed effect concentration; NOEC = (375 mg/kg). Exposure to PU-MPs did not affect C. riparius larval length nor cumulative and time to emergence. Conversely, when exposed to an environmentally relevant concentration for 10 days, contaminated larvae were revealed to be lighter (but not smaller nor less nutritionally affected in terms of energy reserves) and more active when foraging, which was reflected in the activation of their aerobic metabolism when assessing the electron transport chain as a proxy. Notwithstanding, PU-MPs did not originate observable energy costs, either on protein, lipid, or sugar contents on contaminated larvae, which may justify the absence of effects on larval growth and emergence. Therefore, the increased production of energy used for the locomotion and functioning of larvae was at the expense of the fraction of energy that should have been allocated for the weight of the individuals. A long-term exposure involving a multigenerational assessment would bring intel on the potential (cumulative) sub-lethal effects of PU-MPs on C. riparius fitness.


Asunto(s)
Chironomidae , Contaminantes Químicos del Agua , Humanos , Animales , Microplásticos/toxicidad , Plásticos/farmacología , Poliuretanos/farmacología , Ecosistema , Contaminantes Químicos del Agua/análisis , Larva
5.
Health Place ; 71: 102664, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34507035

RESUMEN

AIM: The present study systematically reviewed the characteristics of the food environment in schools and their immediate vicinities associated with excess weight in adolescents. METHODS: We searched for relevant articles in seven databases. No restrictions were applied on language, publication date, and status of publication. The study selection process and data extraction were conducted by two authors independently. For meta-analyses, the random-effects model and the maximum-likelihood method were applied. RESULTS: A total of 9327 publications were identified from the initial search. Of these, 20 studies met the inclusion criteria and were included in the systematic review. The sale of food in school or immediate vicinity was associated with high BMI [Odds ratio (OR)= 1.14, 95% confidence interval (CI) 1.01, 2.06]. The availability of healthy food provided by school significantly decreased the odds of obesity [OR= 0.89, 95%CI 0.82, 0.96]. However, the presence of nutrition policies or programs at school was not associated with obesity (OR= 0.81, 95%CI 0.57, 1.16). CONCLUSIONS: This study highlights the need for improvement in school food environment, including restricting students' exposure to unhealthy foods. The quality of food (healthy vs unhealthy) provided or made available to adolescents in the school food environment influences their weight status. Therefore, promotion of healthy food programs and availability of healthy food at school would limit the prevalence of excess weight in adolescents.


Asunto(s)
Instituciones Académicas , Estudiantes , Adolescente , Humanos , Política Nutricional , Obesidad , Aumento de Peso
6.
Nutrients ; 9(7)2017 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-28704932

RESUMEN

Non-communicable diseases, including cardiovascular diseases, are responsible for over 70% of deaths in Brazil. Currently, over 25% of Brazilian adults are diagnosed as hypertensive; overall, current dietary sodium intake in Brazil (4700 mg/person) is over twice the international recommendations, and 70-90% of adolescents and adults consume excessive sodium. National sodium reduction strategies consider the main dietary sources of sodium to be added salt to foods, foods consumed outside of the household, and sodium in processed foods. The national voluntary strategy for sodium reduction in priority food categories has been continuously monitored over a 6-year period (2011-2017) and there was a significant 8-34% reduction in the average sodium content of over half food categories. Different food categories have undergone differing reductions in sodium over time, aiding gradual biannual targets to allow industries to develop new technologies and consumers to adapt to foods with less salt. By 2017, most products of all food categories had met the regional targets proposed by the Pan American Health Organization, showing that voluntary sodium reduction strategies can potentially contribute to food reformulation. Nevertheless, regulatory approaches may still be necessary in the future in order to reach all food producers and to allow stronger enforcement to meet more stringent regional targets.


Asunto(s)
Análisis de los Alimentos , Sodio en la Dieta/administración & dosificación , Brasil , Dieta , Estudios de Seguimiento , Manipulación de Alimentos , Embalaje de Alimentos , Política Nutricional
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