Indoor air pollution on nurseries and primary schools: impact on childhood asthma – study protocol

BACKGROUND: Several studies have demonstrated an association between the exposure to indoor air pollution (IAP) and childhood asthma. Evidence is suggesting that several air pollutants may contribute to both exacerbation and development of asthma, but some uncertainty remains concerning the specific causative role of IAP. This paper reports an epidemiologic study aiming to reduce the existing lacks on the association between long-term exposure to pollution mixtures and the development and exacerbation of childhood asthma. METHODS/DESIGN: Based on the implementation of the study in 8 nurseries and 8 primary schools, from which, 2 nurseries and 2 primary schools in sites influenced by traffic and other 2 nurseries and 2 primary schools in background sites at urban and rural areas, the study will analyse the exposure to both urban and rural pollution as well as to traffic emissions (some homes of the children will be included in the study). Furthermore, based on the answers to validated questionnaires (as those used in the International Study of Asthma and Allergies in Childhood - ISAAC) filled in by the parents and on medical exams, the study will assess the prevalence, incidence and exacerbation of asthma, thus considering both short and long-term effects. The approximate number of children in the study will never be less than 600, guaranteeing 80% of study power (significant at a 5% level). DISCUSSION: This study intends to contribute for the understanding of the role of environmental factors, namely indoor air pollution, on asthma considering a risk group of different ages, and for the development of preventive measures, which are considered priority issues by the European Commission, according to the European Environmental Agency and the World Health Organization

New dextrin nanomagnetogels: production, characterization and in vivo performance as dual modality imaging bioprobe

Dual modality contrast agents, such as radiolabelle d magnetic nanoparticles, are promising candidates for a number of diagnostic applications, since they combine two complementing imaging modalities, namely photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI). The benefit of such combin ation lies on the ability to interpret more accurately abnormalities in vivo , by integrating the high sensitivity of SPECT with the superb spatial resolution and anatomical information provi ded by MRI [1]. Superparamagnetic iron oxide nanoparticles (SPION) have been extensively s tudied as MRI contrast agents [2]. SPIONs need to be coated in order to allow formulation in aqueous solutions and to increase in vivo stability [3]. Dextrin nanomagnetogels consists on superparamagnet ic iron oxide nanoparticles ( γ -Fe 2 O 3 ) stabilized within hydrophobized-dextrin nanogel (sc heme 1). The nanomagnetogel formulation, with about 4 mM of iron and a diameter of 100 nm, p resents relevant features such as superparamagnetic behaviour, high stability, narrow size distribution and potential for magnetic guidance to target areas by means of an external ma gnetic field [4]. The functionalization of the dextrin nanomagnetogel with a DOTA-monoamide ω -thiol metal chelator and radiolabelling with 111 In were used to ascertain its in vivo stability and behavior (blood clearance rate and o rgan distribution) after intravenous administration in m ice model. The surface modification of the nanomagnetogel with PEG 5,000 was accomplished in a n attempt to escape the phagocytic system. The unloaded radiolabeled dextrin nanogel ( around 30 nm) showed lower uptake in the liver, spleen and kidneys than the nanomagnetogel l oaded with SPIONs (around 110 nm). This difference in biodistribution profile can be ascrib ed to the differences in the particle size. Nanomagnetogel pegylation resulted in lower liver a nd spleen accumulation. The blood half-life obtained was approximately 4 hours for all formulat ions. A good correlation between the amount of polymer (quantified through radioactivity) and t he amount of iron (ICP measurement) in the spleen was observed, indicating that leakage of iro n from the nanomagnetogels after intravenous administration was negligible. The pilo t imaging study demonstrated good performance of dextrin nanomagnetogels as dual moda lity imaging (MRI and SPECT) bioprobes as expected by the high transverse relaxi vity (215-248 mM -1 s -1 ) obtained in vitro , higher than those of commercial available formulati ons (160-177 mM -1 s -1 ). The production of the nanomagnetogel is simple and easy to scale up, thus offering great technological potential

Bacterial cellulose nanocrystals or nanofibrils as Pickering stabilizers in low-oil emulsions: A comparative study

Supplementary data to this article can be found online at https://doi. org/10.1016/j.foodhyd.2024.110427.This investigation assessed the potential of bacterial cellulose (BC) in two distinct forms, nanocrystals (BC-NC) and oxidized nanofibrils (BC-NF), as stabilizers for low oil-in-water emulsions (1 % v/v). The research explored the impact of ionic strength and BC concentration on the physico-chemical characteristics, stability, and rheological properties of those emulsions. Nanofibrils had diameters ranging from 25 to 146 nm and lengths in the micrometer range, while nanocrystals varied in length from 133 to 870 nm and in diameter from 20 to 60 nm. Both BC-NF and BC-NC exhibited high zeta potential values (>45 mV) and contact angles of 30-31°, indicating stability. Both nanocelluloses were effectively used as stabilizers in Pickering emulsions, namely in low-oil systems, producing small emulsion droplets with sizes between 1.42 and 4.13 m. Further results revealed that ionic strength influenced emulsion stability, with both BC-NF and BC-NC preferentially located on the surfaces of emulsion droplets in the presence of salt, as demonstrated by microscopy images. The presence of BC at the interface contributed to creating a more robust barrier against coalescence and Ostwald ripening, influencing droplet size and rheological properties. Higher BC concentrations (1 %) increased emulsion stability in the absence of salt, while at lower BC concentrations (0.5 %), salt concentration was determinant for the long-term stability of the emulsions. These findings provide valuable insights into the production of Pickering emulsions using nanocelluloses, highlighting the advantages of bio-based nanomaterials for applications in the food industry.The author Ana Isabel Bourbon acknowledges FCT funding, through the individual scientific employment program contract (2020.03447.CEECIND). The authors Morsyleide de Freitas Rosa and Nayra de Oliveira Frederico Pinto acknowledges funding by FCT/CAPES 99999.008530/2014–09.info:eu-repo/semantics/publishedVersio

Dextrin-based nanomagnetogel: in vivo biodistribution and stability

The biodistribution profile of a new dextrin nanomagnetogel, which consists on -Fe2O3 superparamagnetic nanoparticles loaded within a polymeric matrix of modified dextrin, was studied in mice. The nanomagnetogel bear a monomodal size distribution profile (average diameter 110 nm) close to neutral surface charge and higher relaxivity (r2 = 215-248 mM-1s-1 and r2/r1 = 13-11) than those of commercial formulations (r2 = 160-177 mM-1s-1 and r2/r1 = 4-7). Also the observed blood half-life - approximately 4 hours - is superior to that of similar commercially available formulations, which remain few minutes in circulation. Pegylation resulted in 1.7 and 1.2-fold lower accumulation in the liver and spleen, respectively, within the first 24 h. Noteworthy, a good correlation was obtained between the amount of polymer (quantified by scintigraphy) in the spleen, 48 h after administration, and the amount of iron physically loaded through hydrophobic interactions (quantified by ICP) indicating the absence of iron leakage from the polymeric matrix. This study provides evidence on the in vivo stability of a self-assembled nanomagnetogel, a much relevant feature which is seldom reported in the literature.The authors thank the Project “strong>BioHealth - Biotechnology and Bioengineering approaches to improve health quality”, Ref. NORTE-07-0124-FEDER-000027, co-funded by the Programa Operacional Regional do Norte (ON.2 O Novo Norte), QREN, FEDER. The authors thank the Magnisense Corporation for providing a MIAplex Reader and CFGCG the EU COST TD1004 Action “Theragnostics Imaging and Therapy”. The authors thank Professor Cidália Botelho for the iron analysis by Atomic Absorbance Spectroscopy at the Oporto University, Chemical Engineering Department. C. Gonçalves, J. P. Silva, J. A. Martins, and M. F. M. Ferreira acknowledge FCT Portugal, for postdoc grants SFRH/BPD/70524/2010 and SFRH/BPD/64958/2009, sabbatical grant SFRH/BSAB/ 1328/2013 and PhD grant SFRH/BD/63994/2009, respectively

The effect of the matrix system in the delivery and in-vitro bioactivity of microencapsulated oregano essential oil

Microencapsulation allows bioactive compounds protection from external factors. Innovation in food industry often requires adding functional ingredients, to tailor flavour and texture, to improve preservation, to control bioactive compounds stability and controlled release during processing/storage. Oregano, besides richness in aroma compounds, is also known by potential antioxidant and antimicrobial activities. These sensitive compounds need protection in order to allow their use in a wider range of processes. In this study, oregano essential oil (EO) was microencapsulated by spray/freeze drying in: rice starch (with/without bonding agents), gelatine/sucrose and inulin, dried at different temperatures. Microencapsulates were analysed for morphology and structure (SEM, CLSM, X-ray diffraction and FTIR). Releasing ability of entrapped EO (UV–VIS spectroscopy) was evaluated by diffusion coefficient (D). Antioxidant activity (AA) - ORAC and HORAC- and antimicrobial activities against pathogens were evaluated. Rice starch spherules, presenting interconnecting cavities, were formed. Spray-dried inulin and gelatine/sucrose systems formed continuous walled and smooth surface spherical capsules (3-4.5 and 0.9-10m, respectively). EO was uniformly distributed inside the structures (CLSM) and its presence confirmed by FTIR. Depending on the system, D varied among 10-13 (starch), 10-13-10-15, (gelatine/sucrose) and 10-16 m2/s (inulin). In starch system, D was mainly influenced by the gelatin concentration, increasing with it. X- ray diffraction and FTIR results suggest some kind of linkage between gelatine and starch. Spray-dried gelatine/sucrose system, revealed to be unsuitable for EO encapsulation due to capsules disintegration but freeze-drying was effective. The D of EO from inulin capsules decreases when these are produced above 140 ºC. The impact of encapsulation method on EO bioactivity and product stability during 6 months, was verified through the determination of microcapsules AA, using free EO value as reference. The results obtained provide information on the release/stability of oregano EO from different matrices, relevant for functional ingredients microencapsulation

Unexpected short- and long-term effects of chronic adolescent HU-210 exposure on emotional behavior

© 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by- nc-nd/4.0/).Chronic adolescent cannabinoid receptor agonist exposure has been shown to lead to persistent increases in depressive-like behaviors. This has been a key obstacle to the development of cannabinoid-based therapeutics. However, most of the published work has been performed with only three compounds, namely Δ9-tetrahydrocannabinol, CP55,940 and WIN55,212-2. Hypothesizing that different compounds may lead to distinct outcomes, we herein used the highly potent CB1R/CB2R full agonist HU-210, and first aimed at replicating cannabinoid-induced long-lasting effects, by exposing adolescent female Sprague-Dawley rats to increasing doses of HU-210, for 11 days and testing them at adulthood, after a 30-day drug washout. Surprisingly, HU-210 did not significantly impact adult anxious- or depressive-like behaviors. We then tested whether chronic adolescent HU-210 treatment resulted in short-term (24h) alterations in depressive-like behavior. Remarkably, HU-210 treatment simultaneously induced marked antidepressant- and prodepressant-like responses, in the modified forced swim (mFST) and sucrose preference tests (SPT), respectively. Hypothesizing that mFST results were a misleading artifact of HU-210-induced behavioral hyperreactivity to stress, we assessed plasmatic noradrenaline and corticosterone levels, under basal conditions and following an acute swim-stress episode. Notably, we found that while HU-210 did not alter basal noradrenaline or corticosterone levels, it greatly augmented the stress-induced increase in both. Our results show that, contrary to previously studied cannabinoid receptor agonists, HU-210 does not induce persisting depressive-like alterations, despite inducing marked short-term increases in stress-induced reactivity. By showing that not all cannabinoid receptor agonists may induce long-term negative effects, these results hold significant relevance for the development of cannabinoid-based therapeutics.Work was supported by project funding from Fundação para a Ciência e para a Tecnologia (FCT) (PTDC/MED-FAR/30933/2017 and PTDC/MED-FAR/4834/2021) and by H2020-WIDESPREAD-05-2017-Twinning (EpiEpinet) under grant agreement No. 952455. MF-F (SFRH/BD/147505/2019), NR (PD/BD/113463/2015), JF-G (PD/BD/114441/2016) and CM-L (SFRH/BD/118238/2016) are supported by PhD fellowships from FCT. The funding sources had no involvement in study design, preparation of the manuscript, or decision regarding its submission.info:eu-repo/semantics/publishedVersio

Behavioural stress responses predict environmental perception in European sea bass (Dicentrarchus labrax)

Individual variation in the response to environmental challenges depends partly on innate reaction norms, partly on experience-based cognitive/emotional evaluations that individuals make of the situation. The goal of this study was to investigate whether pre-existing differences in behaviour predict the outcome of such assessment of environmental cues, using a conditioned place preference/avoidance (CPP/CPA) paradigm. A comparative vertebrate model (European sea bass, Dicentrarchus labrax) was used, and ninety juvenile individuals were initially screened for behavioural reactivity using a net restraining test. Thereafter each individual was tested in a choice tank using net chasing as aversive stimulus or exposure to familiar conspecifics as appetitive stimulus in the preferred or non preferred side respectively (called hereafter stimulation side). Locomotor behaviour (i.e. time spent, distance travelled and swimming speed in each tank side) of each individual was recorded and analysed with video software. The results showed that fish which were previously exposed to appetitive stimulus increased significantly the time spent on the stimulation side, while aversive stimulus led to a strong decrease in time spent on the stimulation side. Moreover, this study showed clearly that proactive fish were characterised by a stronger preference for the social stimulus and when placed in a putative aversive environment showed a lower physiological stress responses than reactive fish. In conclusion, this study showed for the first time in sea bass, that the CPP/CPA paradigm can be used to assess the valence (positive vs. negative) that fish attribute to different stimuli and that individual behavioural traits is predictive of how stimuli are perceived and thus of the magnitude of preference or avoidance behaviour.European Commission [265957]; Portuguese Fundacao para a Ciencia e Tecnologia (FCT) [FRH/BPD/72952/2010]; FCT [SFRH/BD/80029/2011

Influence of passage number on the impact of the secretome of adipose tissue stem cells on neural survival, neurodifferentiation and axonal growth

Mesenchymal stem cells (MSCs), and within them adipose tissue derived stem cells (ASCs), have been shown to have therapeutic effects on central nervous system (CNS) cell populations. Such effects have been mostly attributed to soluble factors, as well as vesicles, present in their secretome. Yet, little is known about the impact that MSC passaging might have in the secretion therapeutic profile. Our aim was to show how human ASCs (hASCs) passage number influences the effect of their secretome in neuronal survival, differentiation and axonal growth. For this purpose, post-natal rat hippocampal primary cultures, human neural progenitor cell (hNPCs) cultures and dorsal root ganglia (DRGs) explants were incubated with secretome, collected as conditioned media (CM), obtained from hASCs in P3, P6, P9 and P12. Results showed no differences when comparing percentages of MAP-2 positive cells (a mature neuronal marker) in neuronal cultures or hNPCs, after incubation with hASCs secretome from different passages. The same was observed regarding DRG neurite outgrowth. In order to characterize the secretomes obtained from different passages, a proteomic analysis was performed, revealing that its composition did not vary significantly with passage number P3 to P12. Results allowed us to identify several key proteins, such as pigment epithelium derived factor (PEDF), DJ-1, interleucin-6 (IL-6) and galectin, all of which have already proven to play neuroprotective and neurodifferentiating roles. Proteins that promote neurite outgrowth were also found present, such as semaphorin 7A and glypican-1. We conclude that cellular passaging does not influence significantly hASCs's secretome properties especially their ability to support post-natal neuronal survival, induce neurodifferentiation and promote axonal growth.Prémios Santa Casa Neurociências - Prize Melo e Castro for Spinal Cord Injury Research (MC-17-2013 and MC-04-2017), Canada Research Chair in Biomedical Engineering (LAB), Northern Portugal Regional Operational Programme (NORTE 2020),, European Regional Development Fund (FEDER), Competitiveness Factors Operational Programme (COMPETE), National Mass Spectrometry Network (RNEM)info:eu-repo/semantics/publishedVersio

Comparative structural response of two steel bridges constructed 100 years apart

This paper presents a comparative numerical analysis of the structural behaviour and seismic performance of two existing steel bridges, the Infiernillo II Bridge and the Pinhao Bridge, one located in Mexico and the other in Portugal. The two bridges have similar general geometrical characteristics, but were constructed 100 years apart. Three-dimensional structural models of both bridges are developed and analysed for various load cases and several seismic conditions. The results of the comparative analysis between the two bridges are presented in terms of natural frequencies and corresponding vibration modes, maximum stresses in the structural elements and maximum displacements. The study is aimed at determining the influence of a 1 century period in material properties, transverse sections and expected behaviour of two quite similar bridges. In addition, the influence of the bearing conditions in the global response of the Pinhao Bridge was evaluated