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1.
Int J Mol Sci ; 25(10)2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38791576

RESUMO

Obstructive sleep apnea (OSA) is quite prevalent during pregnancy and is associated with adverse perinatal outcomes, but its potential influence on fetal development remains unclear. This study investigated maternal OSA impact on the fetus by analyzing gene expression profiles in whole cord blood (WCB). Ten women in the third trimester of pregnancy were included, five OSA and five non-OSA cases. WCB RNA expression was analyzed by microarray technology to identify differentially expressed genes (DEGs) under OSA conditions. After data normalization, 3238 genes showed significant differential expression under OSA conditions, with 2690 upregulated genes and 548 downregulated genes. Functional enrichment was conducted using gene set enrichment analysis (GSEA) applied to Gene Ontology annotations. Key biological processes involved in OSA were identified, including response to oxidative stress and hypoxia, apoptosis, insulin response and secretion, and placental development. Moreover, DEGs were confirmed through qPCR analyses in additional WCB samples (7 with OSA and 13 without OSA). This highlighted differential expression of several genes in OSA (EGR1, PFN1 and PRKAR1A), with distinct gene expression profiles observed during rapid eye movement (REM)-OSA in pregnancy (PFN1, UBA52, EGR1, STX4, MYC, JUNB, and MAPKAP). These findings suggest that OSA, particularly during REM sleep, may negatively impact various biological processes during fetal development.


Assuntos
Sangue Fetal , Desenvolvimento Fetal , Apneia Obstrutiva do Sono , Humanos , Feminino , Gravidez , Sangue Fetal/metabolismo , Adulto , Apneia Obstrutiva do Sono/genética , Desenvolvimento Fetal/genética , Transcriptoma , Perfilação da Expressão Gênica , Complicações na Gravidez/genética
2.
Inorg Chem ; 63(19): 8642-8653, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38690944

RESUMO

The synthesis, structure, and catalytic activity of a Ti(II)/Ti(III) inverted sandwich compound are presented in this study. Synthesis of the arene-bridged dititanium compound begins with the preparation of the titanium(IV) precursor [TiCl2(MesPDA)(thf)2] (MesPDA = N,N'-bis(2,4,6-trimethylphenyl)-o-phenylenediamide) (2). The reduction of 2 with sodium metal results in species [{Ti(MesPDA)(thf)}2(µ-Cl)3{Na}] (3) in oxidation state III. To achieve the lower oxidation state II, 2 undergoes reduction through alkylation with lithium cyclopentyl. This alkylation approach triggers a cascade of reactions, including ß-hydride abstraction/elimination, hydrogen evolution, and chemical reduction, to generate the Ti(II)/Ti(III) compound [Li(thf)4][(TiMesPDA)2(µ-η6: η6-C6H6)] (4). X-ray and EPR characterization confirms the mixed-valence states of the titanium species. Compound 4 catalyzes a mild, efficient, and regiospecific cyclotrimerization of alkynes to form 1,3,5-substituted arenes. Kinetic data support a mechanism involving a binuclear titanium arene compound, similar to compound 4, as the resting state. The active catalyst promotes the oxidative coupling of two alkynes in the rate-limiting step, followed by a rapid [4 + 2] cycloaddition to form the arene product. Computational analysis of the resting state for the cycloaddition of trimethylsilylacetylene indicates a thermodynamic preference for stabilizing the 1,3,5-arene within the space between the two [TiMesPDA] fragments, consistent with the observed regioselectivity.

4.
Sci Data ; 10(1): 872, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057322

RESUMO

In the summer of 2012, two fires affected Mediterranean ecosystems in the eastern Iberian Peninsula. The size of these fires was at the extreme of the historical variability (megafires). Animals are traditionally assumed to recolonize from source populations outside of the burned area (exogenous regeneration) while plants recover from endogenous regeneration (resprouting and seeding). However, there is increasing evidence of in situ fire survival in animals. To evaluate the effect of large-scale fires on biodiversity and the mechanism of recovery, in 2013, we set up 12 plots per fire, covering burned vegetation at different distances from the fire perimeter and unburned vegetation. In each plot, we followed the postfire recovery of arthropods, reptiles (including some of their parasites), and plants for 2 to 5 years. Here we present the resulting database (POSTDIV) of taxon abundance. POSTDIV totals 19,906 records for 457 arthropod taxa (113,681 individuals), 12 reptile taxa (503 individuals), 4 reptile parasites (234 individuals), and 518 plant taxa (cover-abundance). We provide examples in the R language to query the database.


Assuntos
Artrópodes , Incêndios , Animais , Biodiversidade , Ecossistema , Plantas , Répteis , Bases de Dados Factuais
5.
Sci Total Environ ; 903: 166594, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37640071

RESUMO

L'Albufera Natural Park (Valencia, Spain) is a protected wetland of international significance that provides critical habitats to endemic and threatened bird and plant species. This study aims to use multiple cross-validation techniques to generate an accurate estimation of the environmental risk of organic contaminants (OCs) in an internationally important coastal wetland, to identify compounds of concern and their potential sources and risk factors. Microporous polyethylene tube (MPT) passive samplers were deployed at 12 locations across L'Albufera Natural Park with concurrent grab samples collected. A subset of MPT samplers were also analysed by an additional laboratory in Australia to widen the range of contaminants and assess interlaboratory reproducibility of results. Forty-three pesticides, 20 pharmaceuticals and personal care products (PPCPs), 20 per-and polyfluoroalkyl substances (PFAS) and 4 organophosphorus flame retardants (OPFRs) were detected in the MPT samplers. The fungicides tebuconazole and difenoconazole were detected at the highest concentrations in passive samplers (maximum concentrations, 153 ng sampler-1 and 106 ng sampler-1, respectively). Several other pesticides were detected in all locations (mean concentrations >1 ng sampler-1). The compounds fenamiphos, propyzamide, difenoconazole, propiconazole, metsulfuron methyl, sodium bis (perfluorohexyl) phosphinate (6:6 PFPiA), 6:2 fluorotelomer sulfonamide alkylbetaine (6:2 FTAB), 6:2 fluorotelomersulfonate (6:2 FTS), citalopram desmethyl and citalopram were reported in the wetland for the first time. Spatial distribution analysis revealed higher pesticide concentrations in the North of L'Albufera. A risk quotient (RQ) analysis showed that ibuprofen is of concern in the area. Overall, the MPT sampling approach is promising as a risk assessment tool for better understanding the transport and fate of OCs in protected areas.

6.
Methods Mol Biol ; 2601: 303-312, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36445591

RESUMO

A strategy that can be applied to the research of new molecules with antibacterial activity is to look for inhibitors of essential bacterial processes within large collections of chemically heterogeneous compounds. The implementation of this approach requires the development of assays aimed at the identification of molecules interfering with specific cell pathways that can also be used in high-throughput analysis of large chemical libraries. Here, we describe a fluorescence-based whole-cell assay in Escherichia coli devised to find inhibitors of the translation initiation pathway. Translation is a complex and essential mechanism. It involves numerous sub-steps performed by factors that are in many cases sufficiently dissimilar in bacterial and eukaryotic cells to be targetable with domain-specific drugs. As a matter of fact, translation has been proven as one of the few bacterial mechanisms pharmacologically tractable with specific antibiotics. The assay described in this updated chapter is tailored to the identification of molecules affecting the first stage of translation initiation, which is the most dissimilar step in bacteria versus mammals. The effect of the compounds under analysis is measured in living cells, thus allowing evaluation of their in vivo performance as inhibitors of translation initiation. Compared with other assays for antibacterials, the major advantages of this screen are its simplicity, high mechanism specificity, and amenability to scaling up to high-throughput analyses.


Assuntos
Bactérias , Corantes , Animais , Antibacterianos/farmacologia , Células Eucarióticas , Bioensaio , Escherichia coli , Mamíferos
7.
PeerJ ; 10: e14231, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438583

RESUMO

In recent years, the application of silver nanoparticles (AgNPs) as antibacterial compounds has been widely used in human and veterinary medicine. In this work, we investigated the effects of AgNPs (Argovit-4®) as feed additives (feed-AgNPs) on shrimp (Litopenaeus vannamei) using three different methods: 1) chronic toxicity after 28 days of feeding, 2) Effects against white spot syndrome virus (WSSV) challenged by oral route, and 3) transcriptional responses of immune-related genes (PAP, ProPO, CTL-3, Crustin, PEN3, and PEN4) following WSSV infection. The results showed that the feed-AgNPs did not interfere with the growth and survival of shrimp. Also, mild lesions in the hepatopancreas were recorded, proportional to the frequency of the feed-AgNP supply. Challenge test versus WSSV showed that feeding every 7 days with feed-AgNPs reduced mortality, reaching a survival rate of 53%, compared to the survival rates observed in groups fed every 4 days, daily and control groups of feed-AgNPs for the 30%, 10%, and 7% groups, respectively. Feed-AgNPs negatively regulated the expression of PAP, ProPO, and Crustin genes after 28 days of treatment and altered the transcriptional responses of PAP, ProPO, CTL-3, and Crustin after WSSV exposure. The results showed that weekly feeding-AgNPs could partially prevent WSSV infection in shrimp culture. However, whether or not transcriptional responses against pathogens are advantageous remains to be elucidated.


Assuntos
Nanopartículas Metálicas , Penaeidae , Vírus da Síndrome da Mancha Branca 1 , Animais , Humanos , Vírus da Síndrome da Mancha Branca 1/genética , Prata/toxicidade , Nanopartículas Metálicas/toxicidade , Imunidade , Penaeidae/genética
10.
Arch Bronconeumol ; 58(3): 219-227, 2022 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35312598

RESUMO

INTRODUCTION: Obstructive sleep apnea (OSA) increases the risk of type 2 diabetes, and hyperinsulinemia. Pregnancy increases the risk of OSA; however, the relationship between OSA and gestational diabetes mellitus (GDM) is unclear. We aimed (1) to evaluate OSA prevalence in GDM patients; (2) to assess the association between OSA and GDM; and (3) to determine the relationships between sleep parameters with insulin resistance (IR). METHODS: A total of 177 consecutive women (89 with GDM, 88 controls) in the third trimester of pregnancy underwent a hospital polysomnography. OSA was defined when the apnea-hypopnea index (AHI) was ≥5h-1. RESULTS: Patients with GDM had higher pregestational body mass index (BMI) and neck circumference than controls, but no differences in snoring or OSA-symptoms, or AHI (3.2±6.0 vs. 1.9±2.7h-1, p=.069). OSA prevalence was not significantly different in both groups. We did not identify OSA as a GDM risk factor in the crude analysis 1.65 (95%CI: 0.73-3.77; p=.232). Multiple regression showed that total sleep time (TST), TST spent with oxygen saturation<90% (T90), and maximum duration of respiratory events as independent factors related with homeostasis model assessment of IR, while T90 was the only independent determinant of quantitative insulin sensitivity check index. CONCLUSION: OSA prevalence during the third trimester of pregnancy was not significantly different in patients with GDM than without GDM, and no associations between OSA and GDM determinants were found. We identified T90 and obstructive respiratory events length positive-related to IR, while TST showed an inverse relationship with IR in pregnant women.

11.
Arch. bronconeumol. (Ed. impr.) ; 58(3): 219-227, March 2022. graf, tab
Artigo em Inglês | IBECS | ID: ibc-205831

RESUMO

Introduction: Obstructive sleep apnea (OSA) increases the risk of type 2 diabetes, and hyperinsulinemia. Pregnancy increases the risk of OSA; however, the relationship between OSA and gestational diabetes mellitus (GDM) is unclear. We aimed (1) to evaluate OSA prevalence in GDM patients; (2) to assess the association between OSA and GDM; and (3) to determine the relationships between sleep parameters with insulin resistance (IR).MethodsA total of 177 consecutive women (89 with GDM, 88 controls) in the third trimester of pregnancy underwent a hospital polysomnography. OSA was defined when the apnea-hypopnea index (AHI) was ≥5h−1.ResultsPatients with GDM had higher pregestational body mass index (BMI) and neck circumference than controls, but no differences in snoring or OSA-symptoms, or AHI (3.2±6.0 vs. 1.9±2.7h−1, p=.069). OSA prevalence was not significantly different in both groups. We did not identify OSA as a GDM risk factor in the crude analysis 1.65 (95%CI: 0.73–3.77; p=.232). Multiple regression showed that total sleep time (TST), TST spent with oxygen saturation<90% (T90), and maximum duration of respiratory events as independent factors related with homeostasis model assessment of IR, while T90 was the only independent determinant of quantitative insulin sensitivity check index.ConclusionOSA prevalence during the third trimester of pregnancy was not significantly different in patients with GDM than without GDM, and no associations between OSA and GDM determinants were found. We identified T90 and obstructive respiratory events length positive-related to IR, while TST showed an inverse relationship with IR in pregnant women. (AU)


Introducción: La apnea obstructiva del sueño (AOS) aumenta el riesgo de diabetes tipo 2 e hiperinsulinemia. El embarazo aumenta el riesgo de AOS; sin embargo, la relación entre la AOS y la diabetes mellitus gestacional (DMG) no está clara. Nuestros objetivos fueron (1) evaluar la prevalencia de AOS en pacientes con DMG; (2) evaluar la asociación entre la AOS y la DMG; y (3) determinar las relaciones entre los parámetros del sueño y la resistencia a la insulina (RI).MétodosUn total de 177 mujeres seleccionadas consecutivamente (89 de ellas con DMG, 88 controles) en el tercer trimestre del embarazo se sometieron a una polisomnografía hospitalaria. Se clasificó como AOS un índice de apnea-hipopnea (IAH) de ≥5h-1.ResultadosLas pacientes con DMG presentaban un índice de masa corporal (IMC) pregestacional y una circunferencia del cuello más altos que los controles, pero no hubo diferencias en los ronquidos, otros síntomas de AOS o el IAH (3,2±6,0 frente a 1,9±2,7h-1, p=0,069). La diferencia en la prevalencia de AOS entre ambos grupos no fue significativa. No identificamos la AOS como un factor de riesgo de DMG en el análisis bruto (1,65; IC del 95%: 0,73-3,77; p=0,232). Mediante regresión múltiple se determinó que el tiempo total de sueño (TST), el TST pasado con una saturación de oxígeno <90% (T90) y la duración máxima de los eventos respiratorios eran factores independientes relacionados con el Homeostasis Model Assessment of IR (HOMA-IR), mientras que el T90 fue el único determinante independiente del Quantitative Insulin Sensitivity Check Index (QUICKI).ConclusiónLa diferencia de prevalencia de AOS durante el tercer trimestre del embarazo no fue significativa entre las pacientes con DMG y aquellas sin DMG, y no se encontraron asociaciones entre los factores asociados a AOS y DMG. (AU)


Assuntos
Humanos , Feminino , Diabetes Gestacional , Gravidez em Diabéticas , Apneia Obstrutiva do Sono , Resistência à Insulina , Síndromes da Apneia do Sono
12.
R Soc Open Sci ; 9(1): 211508, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35116158

RESUMO

Cubic (α-phase) NaYF4:Yb,Er upconversion nanoparticles (UCNPs) are uniquely suited to biophotonics and biosensing applications due to their near-infrared excitation and visible red emission (λ ex approx. 660 nm), enabling detection via thick overlying tissue with no bio-autofluorescence. However, UCNP synthesis typically requires high temperatures in combination with either high pressure reaction vessels or an inert atmosphere. Here, we report synthesis of α-phase NaYF4:Yb,Er,Mn UCNPs via the considerably more convenient PVP40-mediated route; a strategy that requires modest temperatures and relatively short reaction time (160°C, 2 h) in open air, with Mn2+ co-doping serving to greatly enhance red emission. The optimal Mn2+ co-doping level was found to be 35 mol %, which decreased the average maximum UCNP Feret diameter from 42 ± 11 to 36 ± 15 nm; reduced the crystal lattice parameter, a, from 5.52 to 5.45 Å; and greatly enhanced UCNP red/green emission ratio in EtOH by a factor of 5.6. The PVP40 coating enabled dispersal in water and organic solvents and can be exploited for further surface modification (e.g. silica shell formation). We anticipate that this straightforward UCNP synthesis method for producing strongly red-emitting UCNPs will be particularly beneficial for deep tissue biophotonics and biosensing applications.

13.
J Environ Manage ; 308: 114587, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35121452

RESUMO

The profiling of emerging organic pollutants present in sludge and generated during wastewater treatment is much more limited than in water. This is mainly due to the difficulty of sludge analysis because of its high content of organic matter and interfering compounds. In this study, a generic extraction method using a mixture of buffered water (pH 4.1) and solid phase extraction (SPE) clean-up was applied to samples of sludge obtained in different treatment plants. This extraction was followed by determination of the contaminants by ultra-high performance liquid chromatography coupled to high resolution mass spectrometry (UHPLC-HRMS), using suspected screening to detect the most relevant organic compounds that access the environment through sludge application. This screening (including >3000 substances, such as, pharmaceuticals, pesticides, metabolites and industrial chemicals) tentatively identified 122 compound and assigned most probable structure to 39. The set of compounds assigned to a probable structure was increased in 14 compounds by searching in a free database of metabolites. Fifteen compounds were unequivocally confirmed against the analytical standard. Pharmaceuticals and personal care products (PPCPs), with 31 substances identified and 8 confirmed were the main group of compounds. Compounds frequently detected in all sludge samples include nucleotides such as adenosine triphosphate, amino acids such as phenylalanine, or peptides such as leu-phe. Altogether, the results of this work highlight the interest of HRMS to draw the profile of organic compounds in complex matrices.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Compostos Orgânicos , Esgotos/química , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise
14.
Inorg Chem ; 61(1): 474-485, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34890181

RESUMO

The reaction of [TaCpRX4] (CpR = η5-C5Me5, η5-C5H4SiMe3, η5-C5HMe4; X = Cl, Br) with SiH3Ph resulted in the formation of the dinuclear hydride tantalum(IV) compounds [(TaCpRX2)2(µ-H)2], structurally identified by single-crystal X-ray analyses. These species react with azobenzene to give the mononuclear imide complex [TaCpRX2(NPh)] along with the release of molecular hydrogen. Analogous reactions between the [{Ta(η5-C5Me5)X2}2(µ-H)2] derivatives and the cyclic diazo reagent benzo[c]cinnoline afford the biphenyl-bridged (phenylimido)tantalum complexes [{Ta(η5-C5Me5)X2}2(µ-NC6H4C6H4N)] along with the release of molecular hydrogen. When the compounds [(TaCpRX2)2(µ-H)2] (CpR = η5-C5H4SiMe3, η5-C5HMe4; X = Cl, Br) were employed, we were able to trap the side-on-bound diazo derivatives [(TaCpRX)2{µ-(η2,η2-NC6H4C6H4N)}] (CpR = η5-C5H4SiMe3, η5-C5HMe4; X = Cl, Br) as intermediates in the N═N bond cleavage process. DFT calculations provide insights into the N═N cleavage mechanism, in which the ditantalum(IV) fragment can promote two-electron reductions of the N═N bond at two different metal-metal bond splitting stages.

15.
Rev. senol. patol. mamar. (Ed. impr.) ; 34(4): 208-213, Oct.-Dic. 2021. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-230540

RESUMO

Introducción No existe un consenso sobre las indicaciones de mastectomía contralateral en pacientes diagnosticadas de cáncer de mama unilateral sin mutación germinal en BRCA1/2. Estudios previos han identificado algunos factores que pueden influir en la toma de la decisión dependientes del tumor, como el tamaño o histología, de la paciente, como la edad, y de la cirugía como la posibilidad de realizar una reconstrucción inmediata o la experiencia del cirujano.MétodosEstudio retrospectivo de una cohorte de 176 pacientes diagnosticadas de CM entre 2010 y 2016 a las que se les realizó cirugía mamaria. Se ha analizado la asociación de características del tumor y de la paciente con la toma de decisión de realizar mastectomía contralateral (MC) o no-MC. Asimismo, se han analizado los datos relacionados con la cirugía y la recurrencia por grupos mediante la curva de incidencia acumulada y el test de Gray.ResultadosEl número de MC se ha incrementado en nuestro centro. No hemos encontrado diferencias significativas en el desarrollo de complicaciones posquirúrgicas entre los 2 grupos de pacientes, pero sí en la estancia hospitalaria, siendo superior para MC. También hemos observado diferencias entre ambas cohortes en edad y tipo de tumor, siendo la MC más frecuente en aquellas pacientes más jóvenes y subtipo luminal A. Hemos hallado diferencias en la incidencia acumulada de recidiva entre ambos subgrupos (p=0,034).ConclusionesEn nuestra cohorte la MC se realiza más frecuentemente en pacientes más jóvenes y con cáncer de mama luminal A.(AU)


Introduction There is no consensus on the indications for contralateral mastectomy (CM) in patients diagnosed with unilateral breast cancer without germline BRCA1/2 mutations. Prior studies have identified some factors that could influence decision-making. These factors include tumoural size and histological type; patient-related factors, such as age; and surgical factors such as the possibility of immediate reconstruction and the surgeon's experience.MethodsRetrospective study of a cohort of 176 patients diagnosed with breast cancer between 2010 and 2016 who underwent breast surgery. We analysed the association between tumoural and patient-related characteristics with the decision to perform CM or not. We also analysed data related to surgery and recurrence by groups by using the cumulative incidence curve and the Gray test.ResultsThe number of CM has increased in our centre. We found no significant differences in the occurrence of post-surgical complications between the two patient groups but length of hospital stay was higher in CM. We also found differences between the two cohorts in age and tumoural type, with CM being more frequent in younger patients and those with luminal A subtype. Differences were found in the cumulative incidence of recurrence between subgroups (p=0.034).ConclusionsIn our cohort, CM was more frequent in younger patients and in those with luminal A breast cancer.(AU)


Assuntos
Humanos , Feminino , Mastectomia Profilática , Mamoplastia , Neoplasias Unilaterais da Mama , Mutação , Genes BRCA1
16.
Front Med (Lausanne) ; 8: 674997, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34796182

RESUMO

Background: Obstructive sleep apnea (OSA) is prevalent in pregnancy and it is associated with adverse pregnancy-related outcomes such as gestational diabetes, pre-eclampsia, and low birth weight. Maternal systemic inflammation is proposed to be one of the main intermediate mechanisms. However, the effects of OSA on systemic inflammation are unknown in normal pregnancy. Methods: Women in the 3rd trimester underwent hospital polysomnography to evaluate whether OSA increases systemic inflammation in normal pregnancy and its potential association with adverse fetal outcomes. OSA was defined as an apnea-hypopnea index (AHI) of ≥ 5 h-1. Plasma cytokines levels (TNF-α, IL-1ß, IL-6, IL-8, and IL-10) were determined by multiple immunoassays. Results: We included 11 patients with OSA and 22 women with AHI < 5 h-1, who were homogeneous in age, and body mass index (BMI). Women with OSA had significant higher levels of TNF-α, IL-1ß, IL-8, and IL-10. We found significant correlations between AHI during REM and TNF-α (r = 0.40), IL-1ß (r = 0.36), IL-6 (r = 0.52), IL-8 (r = 0.43), between obstructive apnea index and TNF-α (r = 0.46) and between AHI and IL-1ß (r = 0.43). We also found that CT90% was related to IL-8 (r = 0.37). There were no significant differences in neonatal characteristics; however, we found inverse correlations between TNF-α and IL-8 with birth weight (both r = -0.48), while IL-8 showed a significant inverse relationship with neonatal gestational age (r = -0.48). Conclusions: OSA in our normal pregnancy population was associated with higher systemic inflammation, which was related to obstructive events, especially during REM sleep. Moreover, systemic inflammation was inversely correlated with neonatal birth weight and age.

17.
Environ Sci Technol ; 55(21): 14607-14616, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34664504

RESUMO

Measurements of chemical persistence in natural environments can provide insight into behavior not easily replicated in laboratory studies. However, it is difficult to find environmental situations suitable for such measurements, particularly for substances with half-lives exceeding several weeks. The objective of this study was to demonstrate that a strategic postflood monitoring campaign can be used to quantify transformation half-lives on the scale of months in a real aquatic system. Water samples were collected in the upper Brisbane River estuary on 36 occasions over 37 weeks and analyzed for 127 pharmaceuticals and personal care products (PPCPs), pesticides, and perfluoroalkyl substances (PFASs). High quality time trend data were obtained for 41 substances. For many of these, data on the input of a wastewater treatment plant to the upper estuary were also obtained. A mass balance model of the estuary stretch was formulated and parametrized using PFASs as persistent benchmarking chemicals. Transformation half-life estimates were obtained for 10 PPCPs and 7 pesticides ranging from 18 to 260 days. Furthermore, insight was obtained into dominant transformation processes as well as the magnitude of chemical inputs to the estuary and their sources. The approach developed shows that under certain conditions, estuaries can be used to quantify the persistence of organic contaminants with half-lives of the order of several months.


Assuntos
Fluorocarbonos , Preparações Farmacêuticas , Poluentes Químicos da Água , Benchmarking , Monitoramento Ambiental , Estuários , Fluorocarbonos/análise , Poluentes Químicos da Água/análise
18.
MethodsX ; 8: 101342, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34430246

RESUMO

One of the aspects considered about the presence of contaminants in the aquatic ecosystems is their possible effect on critically endangered species, as the case of European eel, Anguilla anguilla. However, there is a lack of analytical methods to determine these contaminants due to the complexity of eel matrix (contains 5-20 % of lipids and 5-15 % of proteins). Thus, a multi-residue method using QuEChERS extraction a clean-up based on new specific sorbents (to eliminate lipids) and liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed to determine a mix of 21 contaminants. Compared to the previously reported methods (Degani et al., 1986), which were developed for mussels, in this study, one of the proposed extraction methods were adapted to different fish tissues of higher complexity, such as liver and muscle of A. anguilla.•The effectivity of dispersive solid phase extraction (dSPE) using new specific Enhanced Matrix Removal (EMR-lipid) as clean-up for lipid removal was tested.•Clean extracts of matrices with high protein (5-15 %) and lipid (5-20 %) content were obtained ensuring robustness and durability of the analytical systems.•Emerging contaminants extractable by this procedure comprise four different families (pesticides, perfluoroalkyl substances (PFASs), pharmaceuticals and drugs of abuse). Then, it could be further applied to wide scope screening strategies.

20.
Proc Biol Sci ; 288(1954): 20211230, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34255996

RESUMO

Wildfires are a natural disturbance in many ecosystems. However, their effect on biotic interactions has been poorly studied. Fire consumes the vegetation and the litter layer where many parasites spend part of their life cycles. We hypothesize that wildfires reduce habitat availability for parasites with consequent potential benefits for hosts. We tested this for the lizard Psammodromus algirus and its ectoparasites in a Mediterranean ecosystem. We predicted that lizards in recently burned areas would have lower parasite load (cleaning effect) than those in unburned areas and that this phenomenon implies that lizards spending their entire lives in postfire conditions experience a lower level of parasitism than those living in unburned areas. We compared the ectoparasite load of lizards between eight paired burned/unburned sites, including recent (less than 1 year postfire) and older fires (2-4 years). We found that lizards' ectoparasites prevalence was drastically reduced in recently burned areas. Likewise, lizards in older burned areas showed less evidence of past parasitic infections. Fire disrupted the host-parasite interaction, providing the opportunity for lizards to avoid the negative effects of ectoparasites. Our results suggest that wildfires probably fulfil a role in controlling vector-borne diseases and pathogens, and highlight ecological effects of wildfires that have been overlooked.


Assuntos
Incêndios , Lagartos , Incêndios Florestais , Animais , Ecossistema , Carga Parasitária
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