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1.
Environ Monit Assess ; 194(3): 203, 2022 Feb 19.
Article in English | MEDLINE | ID: mdl-35182211

ABSTRACT

The security of water distribution systems has become the subject of an increasing volume of research over the last decade. Data analysis and machine learning are linked to hydraulic and quality modeling for improving the capacity of water utilities to save lives when faced with the contamination of water networks. This research applies k-nearest neighbor and random forest algorithms to estimate the location of contamination sources at near-real time. Epanet and Epanet-MSX software are used to simulate intrusions of pesticide into water distribution system and the interaction with compounds already present in water bulk. Different pesticide concentrations are considered in the simulations, and chlorine monitoring occurs through placed quality sensors. The results show that random forest can localize [Formula: see text] of contamination scenarios, while the KNN algorithm found [Formula: see text]. Finally, an assessment of contamination spread is made for a better understanding of the impacts of non-localized contamination.


Subject(s)
Water Supply , Water , Data Mining , Environmental Monitoring/methods , Water Quality
2.
J Biomed Inform ; 111: 103584, 2020 11.
Article in English | MEDLINE | ID: mdl-33011296

ABSTRACT

BACKGROUND: The human hand is the part of the body most frequently injured in work related accidents, accounting for a third of all accidents at work and often involving surgery and long periods of rehabilitation. Several applications of Augmented Reality (AR) and Virtual Reality (VR) have been used to improve the rehabilitation process. However, there is no sound evidence about the effectiveness of such applications nor the main drivers of therapeutic success. OBJECTIVES: The objective of this study was to review the efficacy of AR and VR interventions for hand rehabilitation. METHODS: A systematic search of publications was conducted in October 2019 in IEEE Xplore, Web of Science, Cochrane library, and PubMed databases. Search terms were: (1) video game or videogame, (2) hand, (3) rehabilitation or therapy and (4) VR or AR. Articles were included if (1) were written in English, (2) were about VR or AR applications, (3) were for hand rehabilitation, (4) the intervention had tests on at least ten patients with injuries or diseases which affected hand function and (5) the intervention had baseline or intergroup comparisons (AR or VR intervention group versus conventional physical therapy group). PRISMA protocol guidelines were followed to filter and assess the articles. RESULTS: From the eight selected works, six showed improvements in the intervention group, and two no statistical differences between groups. We were able to identify motivators of patients' adherence, namely real-time feedback to the patients, challenge, and increased individualized difficulty. Automated tracking, easy integration in the home setting and the recording of accurate metrics may increase the scalability and facilitate healthcare professionals' assessments. CONCLUSIONS: This systematic review provided advantages and drivers for the success of AR/VR application for hand rehabilitation. The available evidence suggests that patients can benefit from the use of AR or VR interventions for hand rehabilitation.


Subject(s)
Augmented Reality , Video Games , Virtual Reality , Activities of Daily Living , Humans
3.
Materials (Basel) ; 13(6)2020 Mar 20.
Article in English | MEDLINE | ID: mdl-32245058

ABSTRACT

This paper presents the development of metallic thermoresistive thin film, providing an innovative solution to dynamically control the temperature during the injection molding process of polymeric parts. The general idea was to tailor the signal response of the nitrogen- and oxygen-doped titanium-copper thin film (TiCu(N,O))-based transducers, in order to optimize their use in temperature sensor devices. The results reveal that the nitrogen or oxygen doping level has an evident effect on the thermoresistive response of TiCu(N,O) films. The temperature coefficient of resistance values reached 2.29 × 10-2 °C-1, which was almost six times higher than the traditional platinum-based sensors. In order to demonstrate the sensing capabilities of thin films, a proof-of-concept experiment was carried out, integrating the developed TiCu(N,O) films with the best response in an injection steel mold, connected to a data acquisition system. These novel sensor inserts proved to be sensitive to the temperature evolution during the injection process, directly in contact with the polymer melt in the mold, demonstrating their possible use in real operation devices where temperature profiles are a major parameter, such as the injection molding process of polymeric parts.

4.
Sustainability ; 11(12): 3317, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31844557

ABSTRACT

High prevalence of poor mental health is a major public health problem. Natural environments may contribute to mitigating stress and enhancing health. However, there is little evidence on whether community-level interventions intended to increase exposure to natural environments can improve mental health and related behaviours. In the first study of its kind, we evaluated whether the implementation of a programme designed to improve the quality of, and access to, local woodlands in deprived communities in Scotland, UK, was associated with lower perceived stress or other health-related outcomes, using a controlled, repeat cross-sectional design with a nested prospective cohort. Interventions included physical changes to the woodlands and community engagement activities within the woodlands, with data collected at baseline (2013) and post-intervention (2014 and 2015). The interventions were, unexpectedly, associated with increased perceived stress compared to control sites. However, we observed significantly greater increases in stress for those living >500 m from intervention sites. Visits to nearby nature (woods and other green space) increased overall, and moderate physical activity levels also increased. In the intervention communities, those who visited natural environments showed smaller increases in stress than those who did not; there was also some evidence of increased nature connectedness and social cohesion. The intervention costs were modest but there were no significant changes in quality of life on which to base cost-effectiveness. Findings suggest factors not captured in the study may have contributed to the perceived stress patterns found. Wider community engagement and longer post-intervention follow-up may be needed to achieve significant health benefits from woodland interventions such as those described here. The study points to the challenges in evidencing the effectiveness of green space and forestry interventions to enhance health in urban environments, but also to potential benefits from more integrated approaches across health and landscape planning and management practice.

5.
Acta fisiátrica ; 26(4): 204-208, Dez. 2019.
Article in English, Portuguese | LILACS | ID: biblio-1129880

ABSTRACT

Objetivo: Verificar a prevalência de sintomas osteomioarticulares em bombeiros militares do Distrito Federal. Metódo: Trata-se de um estudo transversal, realizado com bombeiros militares de idades entre 18 e 55 anos. Foi utilizado o Questionário Nórdico de Sintomas Osteomusculares e os participantes relataram a ocorrência dos sintomas nos 12 meses e nos sete dias precedentes à entrevista, bem como os afastamentos das atividades no último ano. Os dados foram tabulados no programa Microsoft Excel 2016 e foi feita a estatística descritiva. Resultados: Dos 178 bombeiros participantes, 89% eram do sexo masculino, com idade média de 39 anos e média do índice de massa corporal de 25,93. As regiões de maior prevalência foram a região lombar (20,90%), seguida dos joelhos (14,24%) e da região dorsal (12,26%) nos últimos 12 meses e a região lombar (20,35%), seguida dos joelhos (16,48%) e dos ombros (11,97%) nos últimos sete dias. Conclusão: Verificou-se maior prevalência de sintomas osteomioarticulares na região lombar, joelhos e região dorsal para alterações crônicas, e maior prevalência de sintomas na região lombar, joelhos e ombros para alterações agudas. Os bombeiros apontaram como causas a realização de força, fadiga e/ou cansaço, posturas mantidas por um longo período de tempo, movimentos bruscos e movimentos repetitivos.


Objective: Verify the prevalence of osteomioarticular symptoms in military firefighters in the Federal District. Method: This is a cross-sectional study with military firefighters aged between 18 and 55 years. The Nordic Osteomuscular Symptoms Questionnaire was used and the participants reported the occurrence of symptoms in the 12 months and seven days preceding the interview, as well as the withdrawal of the activities in the last year. The data were tabulated in the Microsoft Excel 2016 program and the descriptive statistics were made. Results: Of the 178 firefighters involved, 89% were males, with a mean age of 39 years and a mean body mass index of 25.93. The regions with the highest prevalence were the lumbar region (20.90%), followed by the knees (14.24%) and the dorsal region (12.26%) in the last 12 months and the lumbar region (20.35%), followed by knees (16.48%) and shoulders (11.97%) in the last seven days. Conclusion: There was a higher prevalence of osteomioarticular symptoms in the lumbar region, knees and dorsal region for chronic changes, and a higher prevalence of symptoms in the lower back, knees and shoulders for acute changes. The firefighters pointed as causes of force, fatigue and /or tiredness, postures maintained for a long period of time, sudden movements and repetitive movements.


Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Cumulative Trauma Disorders/epidemiology , Firefighters , Posture , Brazil/epidemiology , Body Mass Index , Prevalence , Cross-Sectional Studies , Surveys and Questionnaires , Morbidity , Muscle Fatigue , Physical Exertion , Muscle Strength , Fatigue , Musculoskeletal Pain/epidemiology , Military Personnel
6.
Environ Sci Pollut Res Int ; 25(4): 3849-3859, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29178002

ABSTRACT

All-trans retinoic acid (atRA) and 9-cis retinoic acid (9cRA) are two natural derivatives of vitamin A that contribute to the normal vertebrate development by affecting gene expression through the retinoic acid signalling pathway. We show transcriptomic effects of the ectopic addition of atRA or 9cRA to zebrafish embryos at the posthatching embryonic stage. Exposure for 24 or 72 h to sublethal concentrations of both isomers resulted in characteristic transcriptome changes, in which many proliferation and development-related genes became underexpressed, whereas genes related to retinoid metabolism and some metabolic functions became overrepresented. While short and long exposures elicit essentially the same set of genes, atRA specifically induced expression of a specific subset of proteases, likely acting at the extracellular level, and of elements of the response to xenobiotics. These results reflect the well-known antiproliferative activity of retinoids, and they suggest a dysregulation of the developmental process at final stages of embryogenesis. They also indicate a potential role of endopeptidases as markers of developmental alterations, as well as their possible control by the retinoic signalling pathway. We propose to monitor mRNA levels of cyp16a, cyp16b, and cyp16c in zebrafish embryos as a bioassay for retinoid disruption.


Subject(s)
Embryo, Nonmammalian/drug effects , Embryonic Development/drug effects , Transcriptome/drug effects , Tretinoin/toxicity , Zebrafish , Alitretinoin , Animals , Embryonic Development/genetics , Gene Expression Profiling , Isomerism , RNA, Messenger/metabolism , Receptors, Retinoic Acid/genetics , Tretinoin/chemistry , Zebrafish/embryology , Zebrafish/genetics
7.
Mar Pollut Bull ; 114(2): 831-836, 2017 Jan 30.
Article in English | MEDLINE | ID: mdl-27847170

ABSTRACT

Fossil fuels, e.g. gasoline and diesel oil, account for substantial share of the pollution that affects marine ecosystems. Environmental metabolomics is an emerging field that may help unravel the effect of these xenobiotics on seaweeds and provide methodologies for biomonitoring coastal ecosystems. In the present study, FTIR and multivariate analysis were used to discriminate metabolic profiles of Ulva lactuca after in vitro exposure to diesel oil and gasoline, in combinations of concentrations (0.001%, 0.01%, 0.1%, and 1.0% - v/v) and times of exposure (30min, 1h, 12h, and 24h). PCA and HCA performed on entire mid-infrared spectral window were able to discriminate diesel oil-exposed thalli from the gasoline-exposed ones. HCA performed on spectral window related to the protein absorbance (1700-1500cm-1) enabled the best discrimination between gasoline-exposed samples regarding the time of exposure, and between diesel oil-exposed samples according to the concentration. The results indicate that the combination of FTIR with multivariate analysis is a simple and efficient methodology for metabolic profiling with potential use for biomonitoring strategies.


Subject(s)
Environmental Monitoring/methods , Fuel Oils/analysis , Metabolome/drug effects , Ulva/drug effects , Brazil , Gasoline/analysis , Metabolomics , Models, Theoretical , Multivariate Analysis , Principal Component Analysis , Spectroscopy, Fourier Transform Infrared , Ulva/metabolism
8.
Chemosphere ; 156: 428-437, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27192480

ABSTRACT

Refined fuels have considerable share of pollution of marine ecosystems. Gasoline is one of the most consumed fuel worldwide, but its effects on marine benthic primary producers are poorly investigated. In this study, Ulva lactuca was chosen as a biological model due to its cosmopolitan nature and tolerance to high levels and wide range of xenobiotics and our goal was to evaluate the effects of gasoline on ultrastructure and metabolism of that seaweed. The experimental design consisted of in vitro exposure of U. lactuca to four concentrations of gasoline (0.001%, 0.01%, 0.1%, and 1.0%, v/v) over 30 min, 1 h, 12 h, and 24 h, followed by cytochemical, SEM, and biochemical analysis. Increase in the number of cytoplasmic granules, loss of cell turgor, cytoplasmic shrinkage, and alterations in the mucilage were some of the ultrastructural alterations observed in thalli exposed to gasoline. Decrease in carotenoid and polyphenol contents, as well as increase of soluble sugars and starch contents were associated with the time of exposure to the xenobiotic. In combination, the results revealed important morphological and biochemical alterations in the phenotype of U. lactuca upon acute exposure to gasoline. This seaweed contain certain metabolites assigned as candidates to biomarkers of the environmental stress investigated and it is thought to be a promise species for usage in coastal ecosystems perturbation monitoring system. In addition, the findings suggest that U. lactuca is able to metabolize gasoline hydrocarbons and use them as energy source, acting as bioremediator of marine waters contaminated by petroleum derivatives.


Subject(s)
Gasoline/toxicity , Seaweed/drug effects , Ulva/drug effects , Water Pollutants, Chemical/toxicity , Biodegradation, Environmental , Carotenoids/metabolism , Polyphenols/metabolism , Seaweed/metabolism , Seaweed/ultrastructure , Starch/metabolism , Ulva/metabolism , Ulva/ultrastructure
9.
Protoplasma ; 253(1): 111-25, 2016 Jan.
Article in English | MEDLINE | ID: mdl-25772683

ABSTRACT

The effects of the heavy metals copper (Cu) and lead (Pb) on Sargassum cymosum were evaluated by determining uptake capacity, growth rates, photosynthetic efficiency, contents of photosynthetic pigments and phenolic compounds, 2,2-diphenyl-1-picrylhydrazyl radical-scavenging capacity, and morphological and cellular changes. S. cymosum was cultivated with Cu and Pb separately and combined at concentrations of 10, 25, and 50 µM for 7 days in laboratory-controlled conditions. Seaweeds under Cu treatment showed the highest biosorption capacity, and growth rates were significantly reduced compared to the control. The photosynthesis/irradiance curves showed alterations in kinetic patterns in the metal-treated samples. Specifically, Cu treatment alone inhibited electron transport rate (ETR) response, while Pb alone induced it. However, samples treated with both Cu and Pb (Cu + Pb) showed inhibition in ETR. The total amount of pigments increased relative to control. Light microscopy showed an increase in phenolic compounds, with physodes migrating towards cortical cells. Scanning electronic microscopy revealed alterations in the typical rough surface of thallus, when compared with control, especially for Pb treatments. Based on these results, it could be concluded that Cu and Pb are stress factors for S. cymosum, promoting alterations in seaweed metabolism and stimulating protective mechanisms against oxidative stress. However, the high bioaccumulation capacity of both heavy metals indicates a possible application for S. cymosum as a biosorbent agent for contaminated wastewater when metals are in low concentrations.


Subject(s)
Copper/toxicity , Lead/toxicity , Seaweed/drug effects , Seaweed/physiology , Absorption, Physiological/drug effects , Antioxidants/metabolism , Chlorophyll/metabolism , Chlorophyll A , Electron Transport/drug effects , Fluorescence , Phenols/metabolism , Photosynthesis/drug effects , Seaweed/growth & development , Seaweed/ultrastructure , Water/metabolism
10.
Environ Pollut ; 206: 535-42, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26298234

ABSTRACT

Airborne particulate matter (PM) is a recognized risk factor for human populations. Here we assessed the toxic potential of the organic constituents from PM collected in urban and rural sites during warm and cold periods of 2012/2013, and fractionated into 6 size fractions. The finest PM fraction (<0.5 µm) showed the highest biological activity (dioxin-like activity and fish embryotoxicity) in all samples, and the maximal activity was observed in rural samples from the cold period. Zebrafish embryo transcriptome analysis showed a strong induction of the AhR signaling pathway correlated to PAH concentrations. Oxidative stress-related genes and pancreatic and eye-lens gene markers appeared de-regulated in embryos exposed to urban extracts, whereas exposure to rural extracts affected genes implicated in basic cellular functions. The observed effects can be directly related to air pollution-related human disorders, suggesting different potential adverse outcomes for human populations exposed to air pollution from specific sources.


Subject(s)
Air Pollutants/toxicity , Embryonic Development/drug effects , Environmental Monitoring/methods , Particulate Matter/toxicity , Rural Health , Urban Health , Air Pollutants/analysis , Animals , Embryo, Nonmammalian/drug effects , Embryonic Development/genetics , Gene Expression Regulation, Developmental/drug effects , Gene Ontology , Humans , Lens, Crystalline/drug effects , Lens, Crystalline/embryology , Pancreas/drug effects , Pancreas/embryology , Particle Size , Particulate Matter/analysis , Risk Assessment , Zebrafish/embryology
11.
Protoplasma ; 252(5): 1347-59, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25666304

ABSTRACT

By evaluating carotenoid content, photosynthetic pigments and changes in cellular morphology, growth rates, and photosynthetic performance, this study aimed to determine the effect of cadmium (Cd) on the development of young gametophytes of Gelidium floridanum. Plants were exposed to 7.5 and 15 µM of Cd for 7 days. Control plants showed increased formation of new filamentous thallus, increased growth rates, presence of starch grains in the cortical and subcortical cells, protein content distributed regularly throughout the cell periphery, and intense autofluorescence of chloroplasts. On the other hand, plants treated with Cd at concentrations of 7.5 and 15 µM showed few formations of new thallus with totally depigmented regions, resulting in decreased growth rates. Plants exposed to 7.5 µM Cd demonstrated alterations in the cell wall and an increase in starch grains in the cortical and subcortical cells, while plants exposed to 15 µM Cd showed changes in medullary cells with no organized distribution of protein content. The autofluorescence and structure of chloroplasts decreased, forming a thin layer on the periphery of cells. Cadmium also affected plant metabolism, as visualized by a decrease in photosynthetic pigments, in particular, phycoerythrin and phycocyanin contents, and an increase in carotenoids. This result agrees with decreased photosynthetic performance and chronic photoinhibition observed after treatment with Cd, as measured by the decrease in electron transport rate. Based on these results, it was concluded that exposure to Cd affects cell metabolism and results in significant toxicity to young gametophytes of G. floridanum.


Subject(s)
Cadmium/toxicity , Germ Cells, Plant/drug effects , Rhodophyta/drug effects , Water Pollutants, Chemical/toxicity , Carotenoids/metabolism , Chlorophyll/metabolism , Chloroplasts/metabolism , Electron Transport , Germ Cells, Plant/physiology , Germ Cells, Plant/ultrastructure , Photosynthesis , Rhodophyta/cytology , Rhodophyta/physiology
12.
Insights Imaging ; 5(6): 723-30, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25272950

ABSTRACT

OBJECTIVES: Identify radiographers' postures during frequent mammography procedures related to the mammography equipment and patient characteristics. METHODS: A postural task analysis was performed using images acquired during the simulation of mammography positioning procedures. Simulations included craniocaudal/(CC) and mediolateral-oblique/(MLO) positioning in three different settings: radiographers and patients with similar statures, radiographers smaller than the patients and radiographers taller than the patients. Measurements of postural angles were performed by two raters using adequate software and classified according to the European Standard EN1005-4:2005 + A1:2008. RESULTS: The simulations revealed that the most awkward posture in mammography is during the positioning of MLO projection in short-stature patients. Postures identified as causing work-related musculoskeletal disorder (WRMSD) risk were neck extension, arms elevated and the back stooped, presenting angles of 87.2, 118.6 and 63.6, respectively. If radiographers were taller than patients, then the trunk and arm postures were not acceptable. CONCLUSIONS: Working in a mammography room leads to awkward postures that can have an impact on radiographers' health, namely WRMSDs. The results in this study showed that there are non-acceptable postures associated with frequent working procedures in mammography. MLO is the most demanding procedure for radiographer postures and may be related to WRMSDs. Mammography devices should be redesigned considering adjustability for radiographers. MAIN MESSAGES: • Mammography constraints for radiographers in mammography procedures have not been well studied. • Performing mammography leads to awkward postures that can impact radiographers' health. • MLO, the most demanding procedure for radiographers, is possibly related to WRMSDs.

13.
Nanotoxicology ; 8 Suppl 1: 92-9, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24266889

ABSTRACT

The progressive practical applications of engineered nanoparticles results in their ever-increasing release into the environment. Accurate assessment of their environmental and health risks requires the development of methods allowing their monitoring in different environmental compartments and the evaluation of their potential toxicity at different levels of organization. Toxic effects of third-generation (G3) and fourth-generation (G4) poly(amidoamine) dendrimers (ethylenediamine cored, imine-terminated) were assessed on zebrafish embryos during the first two days post-fertilization. Particle characterization by dynamic light scattering showed no tendency to form aggregates in the assay conditions. G3 particles showed somewhat a higher acute toxicity than G4 particles, with LC50 values of 1.8 and 2.3 mg/L, respectively. At sublethal concentrations, both particles affected the zebrafish transcriptome following similar patterns, suggesting a similar mode of action. About 700 transcripts were affected by at least one of the treatments, following a pattern with significant correlations to the effects of bacterial infection in zebrafish embryos. We concluded that the response to G3 and G4 dendrimers was consistent with the activation of the innate immune response, a still unreported potential effect of these particles. These data may contribute to the characterization of hazards of these nanomaterials for both human health and the environment.


Subject(s)
Dendrimers/pharmacology , Transcriptome , Zebrafish/embryology , Animals , Base Sequence , DNA Primers
14.
BMJ Open ; 3(8): e003648, 2013 Aug 30.
Article in English | MEDLINE | ID: mdl-23996826

ABSTRACT

INTRODUCTION: There is a growing body of evidence that suggests that green spaces may positively influence psychological well-being. This project is designed to take advantage of a natural experiment where planned physical and social interventions to enhance access to natural environments in deprived communities provide an opportunity to prospectively assess impacts on perceived stress and mental well-being. STUDY DESIGN AND METHODS: A controlled, prospective study comprising a repeat cross-sectional survey of residents living within 1.5 km of intervention and comparison sites. Three waves of data will be collected: prephysical environment intervention (2013); postphysical environment intervention (2014) and postwoodland promotion social intervention (2015). The primary outcome will be a measure of perceived stress (Perceived Stress Scale) preintervention and postintervention. Secondary, self-report outcomes include: mental well-being (Short Warwick-Edinburgh Mental Well-being Scale), changes in physical activity (IPAQ-short form), health (EuroQoL EQ-5D), perception and use of the woodlands, connectedness to nature (Inclusion of Nature in Self Scale), social cohesion and social capital. An environmental audit will complement the study by evaluating the physical changes in the environment over time and recording any other contextual changes over time. A process evaluation will assess the implementation of the programme. A health economics analysis will assess the cost consequences of each stage of the intervention in relation to the primary and secondary outcomes of the study. ETHICS AND DISSEMINATION: Ethical approval has been given by the University of Edinburgh, Edinburgh College of Art Research, Ethics and Knowledge Exchange Committee (ref. 19/06/2012). Findings will be disseminated through peer-reviewed publications, national and international conferences and, at the final stage of the project, through a workshop for those interested in implementing environmental interventions.

15.
J Steroid Biochem Mol Biol ; 138: 143-51, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23619336

ABSTRACT

Retinoic acid (RA) regulates many developmental processes through its binding to two types of nuclear receptors, the retinoic acid receptor (RAR), and the retinoid-X receptor (RXR), which preferentially binds to the 9-cis isomer. Here we analyzed the RAR/RXR regulatory system during the first 5 days of development of zebrafish. Analysis of the relative transcript abundances for the four RAR and the six RXR zebrafish genes present in the zebrafish genome indicates a transition from maternal to embryonic transcripts during the first 24h post fertilization. These changes did not affect the response to exogenous RA of the known RAR-responsive genes cyp26a1, dhrs3a, hoxb1b, hoxb5a, and hoxb5b. At the transcriptomic level, RA treatment elicited a negative feedback of genes involved in the endogenous RA synthesis and reduced levels of transcripts related to organ and anatomic development. These effects occurred at concentrations at which no morphological changes were observed. Data analysis suggests that exposure to exogenous RA results in an advance of the developing program, activating genes that should remain silent until later developmental stages and inhibiting expression of development-related genes. We conclude that zebrafish embryos are particularly sensitive to potential disruptors of the RAR/RXR regulatory system.


Subject(s)
Receptors, Retinoic Acid/metabolism , Alcohol Oxidoreductases/genetics , Animals , Cytochrome P-450 Enzyme System/genetics , Gene Expression Regulation, Developmental/drug effects , Gene Expression Regulation, Developmental/genetics , Homeodomain Proteins/biosynthesis , Homeodomain Proteins/genetics , Receptors, Retinoic Acid/genetics , Retinoic Acid 4-Hydroxylase , Reverse Transcriptase Polymerase Chain Reaction , Tretinoin/pharmacology , Zebrafish , Zebrafish Proteins/genetics
16.
Aquat Toxicol ; 110-111: 114-22, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22281776

ABSTRACT

Thyroid disruption during early development is a current matter of concern due to its significant human health implications. We present here a transcriptome analysis of thyroid hormone-regulated genes in zebrafish during the eleutheroembryonic stage (days 2-5 post fertilization) to detect potential markers of thyroid disruption. Exposure to 3,5,3'-triiodo-l-thyroxine (T3, 50 nM) induced changes in a minor portion (less than 2%) of the zebrafish transcriptome, with a significant fraction of genes involved in the haematopoietic system, eye formation, and ossification/skeletal system, including the thyroid receptor thra gene. Some of the transcriptomic changes were reflected macroscopically, as an allometric decrease of eye size and an increase on thra hybridization signal in the skeletal tissue. Using this information, changes on transcription of three genes (adult alpha globin gene si:ch211-5 k11.6, embryonic globin gene hbae3, and long wavelength cone opsin gene opn1/w1) were analyzed to monitor the effect of the suspected thyroid disrupter bisphenol A (BPA) on the thyroid system during this period of development of zebrafish. BPA acted as a weak T3 agonist when tested alone, but it strongly enhanced the effect of subsaturating concentrations of T3. In thyroxine immunofluorescence quantitative disruption tests (TIQDT), BPA did not prevent the ability of thyroid follicles to synthesize thyroxine, a landmark for direct goitrogens. Our results suggest that BPA potentiates the effect of endogenous T3 in early development and demonstrate the requirement for the use of in vivo, multi-endpoint methods to evaluate thyroid disruption hazards on early developmental processes in vertebrates.


Subject(s)
Embryo, Nonmammalian/drug effects , Phenols/toxicity , Triiodothyronine/metabolism , Water Pollutants, Chemical/toxicity , Zebrafish/embryology , Animals , Benzhydryl Compounds , Embryo, Nonmammalian/metabolism , Embryonic Development/drug effects , Endocrine Disruptors/toxicity , Thyroid Gland/drug effects , Thyroid Hormones/genetics , Thyroxine/genetics , Thyroxine/metabolism , Transcriptome , Triiodothyronine/genetics
17.
Environ Toxicol Chem ; 30(4): 967-72, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21309019

ABSTRACT

Polycyclic aromatic compounds, such as phenanthrene (PHE), tend to accumulate in the soil compartment, where they may be retained for many years because of their persistency and hydrophobicity. The toxicity and bioaccumulation of these chemicals in soil biota and potential biomagnification along the food chain is an issue of concern. The main goal of this study was to determine the toxicity and bioaccumulation of PHE in Enchytraeus albidus (Oligochaeta: Enchytraeidae) in a natural standard soil (LUFA 2.2) following standard test guidelines. Phenanthrene dose-relatedly affected the survival and reproduction of E. albidus with median lethal concentration and median effective concentration (EC50) values of 135 and 33 mg/kg dry soil, respectively. A toxicokinetics study, performed at a nontoxic soil concentration of 8 mg/kg, showed uptake and elimination rate constants of 4.91 kg soil per kilogram fresh weight animal per day and 0.236 per day, respectively and a bioaccumulation factor (BAF) of 20.8 kg soil per kilogram fresh weight animal. These results show that the three-week exposure in the toxicity test with E. albidus is sufficiently long to reach equilibrium, but also that PHE may accumulate to considerable levels, possibly causing a risk for predators.


Subject(s)
Oligochaeta/drug effects , Phenanthrenes/toxicity , Soil Pollutants/toxicity , Animals , Oligochaeta/metabolism , Phenanthrenes/metabolism , Reproduction/drug effects , Soil Pollutants/metabolism
18.
Environ Int ; 36(4): 338-343, 2010 May.
Article in English | MEDLINE | ID: mdl-20227762

ABSTRACT

Triclosan (TCS) is an antimicrobial agent which is used as a broad-spectrum bacteriostatic and found in personal care products, and due to this it is spread in the environment. Aquatic toxicity studies have been reported, but little data is available for its toxicity to terrestrial organisms. The main purpose of this study was to assess the toxicity of TCS in the terrestrial environment, using a battery of soil species, belonging to different taxonomic levels. The species included the invertebrates Eisenia andrei, Enchytraeus albidus and Folsomia candida and the plants Triticum aestivum (monocotyledonous) and Brassica rapa (dicotyledonous). For the invertebrate species the reproduction EC(10)s were 0.6 (E. andrei), 2 (E. albidus) and 7(F. candida) mg TCS/kg soil dry weight (DW). For plants' emergence EC(10)s are 0.1 (B. rapa) and 142 (T. aestivum) TCS/kg soil DW. The calculated PNEC (Predicted No Effect Concentration) ranged between 0.0008 and 0.004mg TCS/kg (95% certainty) and between 0.04 and 0.2mg TCS/kg soil DW (50% certainty) when using the SSD (Species Sensitivity Distribution) approach; applying a safety factor to the lowest EC(10) resulted in a PNEC of 0.06mg TCS/kg soil DW.


Subject(s)
Anti-Bacterial Agents/toxicity , Brassica rapa/drug effects , Invertebrates/drug effects , Triclosan/toxicity , Triticum/drug effects , Animals
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