490 research outputs found

    Metal transfer to sediments, invertebrates and fish following waterborne exposure to silver nitrate or silver sulfide nanoparticles in an indoor stream mesocosm

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    Engineered nanomaterials; Silver uptake; TroutNanomaterials dissenyats; Captació de plata; TruitaNanomateriales de ingeniería; Absorción de plata; TruchaThe fate of engineered nanomaterials in ecosystems is unclear. An aquatic stream mesocosm explored the fate and bioaccumulation of silver sulfide nanoparticles (Ag2S NPs) compared to silver nitrate (AgNO3). The aims were to determine the total Ag in water, sediment and biota, and to evaluate the bioavailable fractions of silver in the sediment using a serial extraction method. The total Ag in the water column from a nominal daily dose of 10 μg L−1 of Ag for the AgNO3 or Ag2S NP treatments reached a plateau of around 13 and 12 μg L−1, respectively, by the end of the study. Similarly, the sediment of both Ag-treatments reached ~380 μg Ag kg−1, and with most of it being acid-extractable/labile. The biota accumulated 4–59 μg Ag g−1 dw, depending on the type of Ag-treatment and organism. The oligochaete worm, Lumbriculus variegatus, accumulated Ag from the Ag2S exposure over time, which was similar to the AgNO3 treatment by the end of the experiment. The planarian, Girardia tigrina, and the chironomid larva, Chironomus riparius, showed much higher Ag concentrations than the oligochaete worms; and with a clearer time-dependent statistically significant Ag accumulation relative to the untreated controls. For the pulmonate snail, Physa acuta, bioaccumulation of Ag from AgNO3 and Ag2S NP exposures was observed, but was lower from the nano treatment. The AgNO3 exposure caused appreciable Ag accumulation in the water flea, Daphnia magna, but accumulation was higher in the Ag2S NP treatment (reaching 59 μg g−1 dw). In the rainbow trout, Oncorhynchus mykiss, AgNO3, but not Ag2S NPs, caused total Ag concentrations to increase in the tissues. Overall, the study showed transfer of total Ag from the water column to the sediment, and Ag bioaccumulation in the biota, with Ag from Ag2S NP exposure generally being less bioavailable than that from AgNO3.This work was supported by the project NanoFASE (Nanomaterial Fate and Speciation in the Environment), financed by the European Union's Horizon 2020 research and innovation programme under grant agreement no 646002. RDH was partly supported by NanoHarmony under grant agreement 885931 in Horizon 2020 while redrafting the main text. PVS was awarded with a PhD grant (SFRH/BD/51571/2014) by FCT – Fundação para a Ciência e a Tecnologia. SL and PVS received additional financial support from FCT/MCTES, through national funds, to CESAM (UIDP/50017/2020+UIDB/50017/2020+ LA/P/0094/2020)

    Providing office workers with height-adjustable workstation to reduce and interrupt workplace sitting time: protocol for the Stand Up for Healthy Aging (SUFHA) cluster randomized controlled trial

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    © The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.Background: Sedentary behavior (SB) has been linked to several negative health outcomes. Therefore, reducing SB or breaking up prolonged periods of SB improves functional fitness, food consumption, job satisfaction, and productivity. Reducing SB can be achieved by introducing a health-enhancing contextual modification promoted by a sit-stand desk in the workplace. The primary goal will be to test the effectiveness of this intervention in reducing and breaking up SB, while improving health outcomes in office-based workers during a 6-month intervention. Methods: A two-arm (1:1), superiority parallel-group cluster RCT will be conducted to evaluate the effectiveness of this intervention in a sample of office-based workers from a university in Portugal. The intervention will consist of a psychoeducation session, motivational prompts, and contextual modification promoted by a sit-stand desk in the workplace for 6 months. The control group will work as usual in their workplace, with no contextual change or prompts during the 6-month intervention. Three assessment points will be conducted in both groups, pre-intervention (baseline), post-intervention, and a 3-month follow-up. The primary outcomes include sedentary and physical activity-related variables, which will be objectively assessed with 24 h monitoring using the ActivPAL for 7 days. The secondary outcomes include (a) biometric indices as body composition, body mass index, waist circumference, and postural inequalities; and (b) psychosocial variables such as overall and work-related fatigue, overall discomfort, life/work satisfaction, quality of life, and eating behavior. Both the primary and secondary outcomes will be assessed at each assessment point. Discussion: This study will lean on the use of a sit-stand workstation for 6 months, prompted by an initial psychoeducational session and ongoing motivational prompts. We will aim to contribute to this topic by providing robust data on alternating sitting and standing postures in the workplace. Trial registration: The trial was prospectively registered, and the details are at: https://doi.org/10.17605/OSF.IO/JHGPW ; Registered 15 November 2022. OSF Preregistration.This study was funded by the ILIND “Fazer+” scientific program (Reference: FAZER+/ILIND/CIDEFES/1/2022).info:eu-repo/semantics/publishedVersio

    Increasing Vegetable Diversity Consumption Impacts the Sympathetic Nervous System Activity in School-Aged Children

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    Evidence about the impact of vegetable and fruit diversity consumption on the autonomic nervous system (ANS) functioning is scarce. In this cross-sectional study (513 participants, 49.9% girls aged 7 to 12 years), we evaluated the association between vegetable and fruit diversity consumption and the ANS in school-aged children. Dietary intake was collected using a single 24-h recall questionnaire. Fruit and vegetable diversity consumption was estimated by summing up all the different individual vegetables and fruits consumed in one day. Pupillometry was used to assess pupillary light response, which evaluated the ANS activity. Adjusted linear regressions estimated the association between vegetable and fruit diversity consumption with pupillary light response measures. There was a positive and significant association between vegetable diversity consumption and the average dilation velocity, a measure related to the sympathetic nervous system activity (beta-coefficient = 0.03, 95%CI: 0.002; 0.07). Our findings show that vegetable diversity consumption is associated with the ANS response, a possible early link between diet and health in school-aged children

    The stress responsive and morphologically regulated hsp90 gene from Paracoccidioides brasiliensis is essential to cell viability

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    <p>Abstract</p> <p>Background</p> <p><it>Paracoccidioides brasiliensis </it>is a dimorphic fungus that causes the most prevalent systemic mycosis in Latin America. The response to heat shock is involved in pathogenesis, as this pathogen switches from mycelium to yeast forms in a temperature dependent fashion that is essential to establish infection. HSP90 is a molecular chaperone that helps in the folding and stabilization of selected polypeptides. HSP90 family members have been shown to present important roles in fungi, especially in the pathogenic species, as an immunodominant antigen and also as a potential antifungal therapeutic target.</p> <p>Results</p> <p>In this work, we decided to further study the <it>Pbhsp90 </it>gene, its expression and role in cell viability because it plays important roles in fungal physiology and pathogenesis. Thus, we have sequenced a <it>Pbhsp90 </it>cDNA and shown that this gene is present on the genome as a single copy. We have also confirmed its preferential expression in the yeast phase and its overexpression during dimorphic transition and oxidative stress. Treatment of the yeast with the specific HSP90 inhibitors geldanamycin and radicicol inhibited growth at 2 and 10 μM, respectively.</p> <p>Conclusion</p> <p>The data confirm that the <it>Pbhsp90 </it>gene encodes a morphologically regulated and stress-responsive protein whose function is essential to cell viability of this pathogen. This work also enforces the potential of HSP90 as a target for antifungal therapies, since the use of HSP90 inhibitors is lethal to the <it>P. brasiliensis </it>yeast cells in a dose-responsive manner.</p

    Hidrocarbonetos e esterois como indicadores de fontes e destino de matéria orgânica em sedimentos da Baía de Sepetiba, Rio de Janeiro

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    The inputs of organic matter derived from natural and anthropogenic sources to Sepetiba Bay were investigated by using aliphatic hydrocarbons and sterols in superficial sediments. Concentrations ranged from 0.26 to 2.65 &#956;g g-1, <0.01 to 17.41 &#956;g g-1 and 0.77 and 9.24 &#956;g g-1 for n-alkanes, UCM (unresolved complex mixture) and total sterols, respectively. The selected markers and ratios among individual compounds showed the major contribution of terrestrial sources to the total pool of sedimentary organic matter in the bay, but the accumulation of autochthonous organic matter increased with distance from the shoreline. The input of petroleum hydrocarbons and sewage (coprostanol in the range 0.01 to 0.43 &#956;g g-1) were also detected, especially in the more urbanized regions of the bay, but at lower levels of contamination when compared to estuaries in other Brazilian coastal regions

    Projeto de Para-sol com Embalagens Tetra Pak

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    A reutilização das embalagens tetra pak, como uma barreira física para conter a entrada da luz solar direta no interior de veículos, vem ao encontro de dois benefícios, o primeiro deles seria, como mais um meio de reciclar as embalagens tetra pak, ou melhor dizendo, aumentar o ciclo de vida do produto, antes de ser descartado. E o segundo benefício, seria bloquear a ação da radiação ultravioleta e infravermelho no interior dos veículos que acelera a desagregação de cor dos materiais, reduzindo a vida útil dos componentes internos. A título de curiosidade, estes componentes internos, que na maioria das vezes são de cor preta, aumenta a temperatura interna do veículo, quando exposto ao sol, chegando a 80°C, devido ao efeito estufa criado, pela reflexão dos raios infravermelhos do painel e tecidos dos bancos, refletindo no vidro, quando é impedido de sair, causando um desconforto térmico aos usuários. Sendo, portanto, uma solução de custo baixo e excelente benefício à aplicação do para-sol com embalagens de tetra pak

    Immobilization of streptavidin on a plasmonic Au-TiO2 thin film towards an LSPR biosensing platform

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    Optical biosensors based on localized surface plasmon resonance (LSPR) are the future of label-free detection methods. This work reports the development of plasmonic thin films, containing Au nanoparticles dispersed in a TiO2 matrix, as platforms for LSPR biosensors. Post-deposition treatments were employed, namely annealing at 400 °C, to develop an LSPR band, and Ar plasma, to improve the sensitivity of the Au-TiO2 thin film. Streptavidin and biotin conjugated with horseradish peroxidase (HRP) were chosen as the model receptor–analyte, to prove the efficiency of the immobilization method and to demonstrate the potential of the LSPR-based biosensor. The Au-TiO2 thin films were activated with O2 plasma, to promote the streptavidin immobilization as a biorecognition element, by increasing the surface hydrophilicity (contact angle drop to 7°). The interaction between biotin and the immobilized streptavidin was confirmed by the detection of HRP activity (average absorbance 1.9 ± 0.6), following a protocol based on enzyme-linked immunosorbent assay (ELISA). Furthermore, an LSPR wavelength shift was detectable (0.8 ± 0.1 nm), resulting from a plasmonic thin-film platform with a refractive index sensitivity estimated to be 33 nm/RIU. The detection of the analyte using these two different methods proves that the functionalization protocol was successful and the Au-TiO2 thin films have the potential to be used as an LSPR platform for label-free biosensors.Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UIDB/04650/2020, UIDB/04050/2020, and UID/EMS/00285/2020, and by the projects NANO4BIO: POCI-01-0145-FEDER-032299, with FCT reference PTDC/FIS-MAC/32299/2017, and CO2Plasmon, with FCT reference EXPL/CTM-REF/0750/2021. Patrícia Pereira-Silva, Diana I. Meira, and Diogo Costa acknowledge FCT for their Ph.D. scholarships, 2020.08235.BD, SFRH/BD/143262/2019, and SFRH/BD/136279/2018, respectively. Augusto Costa-Barbosa also acknowledges FCT for his Ph.D. scholarships SFRH/BD/133513/2017 and COVID/BD/152169/2021. The authors would like to express their gratitude to Nuno P. Barradas (C2TN, University of Lisbon) and Eduardo Alves (IPFN, University of Lisbon) for RBS measurements and analysis

    Wheezing in infants: frequency, clinical characteristics and treatment

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    OBJECTIVE: To estimate the frequency and describe the clinical characteristics and respective treatments of previous history of wheezing. METHODS: Infants aged 6-23 months with upper respiratory tract complaints and reporting previous wheezing were followed-up retrospectively. Data were registered on a validated standardized form. RESULTS: Out of 451 infants, 164 (36.4%; 95%CI: 31.9-41.0) had a report of prior history of wheezing, 148 (32.8%; 95%CI: 28.5-37.4) during the first year of life. The mean age at the first episode of wheezing was 5.3±3.9 months. Among those who had had their first episode before 12 months of age, 38.5% reported 3 to 6 episodes and 14.2% > 6 episodes. Mean age at first episode was lower for those with > 3 episodes in comparison with those with seis episódios. A média da idade no primeiro episódio foi menor para os que apresentaram > três episódios em comparação aos que apresentaram até dois episódios (3,2±2,7 versus 5,7±2,5 meses, p < 0,001). CONCLUSÃO: Um terço dos lactentes apresentou chiado no primeiro ano de vida. Quanto mais cedo ocorre o primeiro episódio, mais frequente é a recorrência do chiado.Fundação de Amparo à Pesquisa do Estado da Bahia (FAPESB)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal da Bahia Faculdade de Medicina da Bahia Programa de Pós-Graduação em Ciências da SaúdeUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de PediatriaUniversidade de São Paulo Faculdade de Saúde Pública Departamento de EpidemiologiaEscola Bahiana de Medicina e Saúde PúblicaUFBAUFBA Faculdade de Medicina da Bahia Departamento de Anatomia Patológica e Medicina LegalUFBA Faculdade de Medicina da Bahia Departamento de PediatriaUNIFESP, EPM, Depto. de PediatriaSciEL
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