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1.
Sci Total Environ ; 903: 166213, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37567298

RESUMO

Per- and polyfluoroalkyl substances (PFASs) are contaminants of global concern due to their ubiquitous occurrence in the environment, bioaccumulation and the adverse effects on organisms. Tawny Owls (Strix aluco) are documented to be exposed to increasing concentrations of perfluoroalkyl carboxylic acids (PFCAs), and have been suggested in literature as a key raptor monitoring species. Therefore, non-destructive biomonitoring efforts are of high interest. Thus far, the use of feathers for biomonitoring PFASs in Tawny Owls has not been investigated. In this study, 32 PFASs were analyzed in 49 Tawny Owl body feather samples collected from 2017 to 2020 in Trøndelag, Norway. There were 30 PFASs detected in at least one feather, with the sum concentrations ranging from 31 to 203 ng/g (w.w.). Perfluoroheptanoic acid (PFHpA) (median: 33 ng/g) and perfluorooctane sulfonamidoacetic acid (FOSAA) (median: 18 ng/g) were the two compounds with the highest concentrations. Perfluorooctane sulfonic acid (PFOS), which is banned for production and use in Norway since 2007, was found in all samples (median: 4.14 ng/g), indicating its high persistence. 8 PFASs were detected in at least 50 % of the samples: FOSAA (11-127 ng/g), PFHpA (<0.04-115 ng/g), perfluorobutanesulfonic acid (PFBS) (<0.28-21 ng/g), PFOS (0.23-13 ng/g), perfluorotridecanoic acid (PFTrDA) (0.24-5.15 ng/g), perfluorododecanoic acid (PFDoDA) (<0.28-4.45 ng/g), perfluoroundecanoic acid (PFUnDA) (<0.28-2.33 ng/g), and 1H,1H,2H,2H-perfluorooctanesulfonic acid (6:2 FTSA) (0.07-1.01 ng/g). No significant differences were found for the concentrations of PFASs between calendar years and locations, but a slight increase could be observed in the sum concentration of PFASs (Æ©32PFASs) over the sampling years. As Tawny Owls are residential owls that usually do not cover great distances, their feathers can be used as a potential alternative matrix for future biomonitoring studies. To our knowledge, this is the first study on the occurrence of 32 PFASs investigated in feathers of a Tawny Owl population.

2.
J Hazard Mater ; 426: 127814, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34836692

RESUMO

Bisphenols and benzophenone UV-filters are hazardous, high production volume chemicals. There is concern that these contaminants could leach into the environment or be recycled into new products during waste management. To investigate this, nine bisphenols and five benzophenones were quantified in Norwegian e-waste and car fluff. To understand their leachability, equilibrium passive sampling methodology, using polyoxymethylene (POM), was calibrated for these substances, many of which for the first time. This method can differentiate freely dissolved substances in the aqueous phase from those sorbed to suspended colloids and microplastics in the leachate water. Equilibrium POM partitioning was reached within 14 days of shaking; all bisphenols and benzophenone UV-filters exhibited linear isotherms (R2 ranged from 0.83 to 1.0), when deriving POM-water partition coefficients (KPOM). Bisphenol A and bisphenol F displayed the highest concentrations, with maximum levels of 246,000 and 42,400 ng g-1, respectively. Logarithms of waste-water partition coefficients (log Kwaste) ranged from 1.7 (benzophenone 2) to 4.5 (bisphenol P). The established KPOM values agreed with measured Kwaste values (within a factor of ~3), unlike octanol-water partition coefficients. This indicated that POM is a better surrogate for waste plastic partitioning than octanol. Results are discussed in the context of assessing risks from waste management in a circular economy.


Assuntos
Resíduo Eletrônico , Poluentes Químicos da Água , Compostos Benzidrílicos , Benzofenonas , Fenóis , Plásticos , Poluentes Químicos da Água/análise
3.
J Chromatogr Sci ; 59(7): 670-680, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479755

RESUMO

High throughput and high-resolution lipid analyses are important for many biological model systems and research questions. This comprises both monitoring at the individual lipid species level and broad lipid classes. Here, we present a nontarget semiquantitative lipidomics workflow based on ultrahigh performance supercritical fluid chromatography (UHPSFC)-mass spectrometry (MS). The optimized chromatographic conditions enable the base-line separation of both nonpolar and polar classes in a single 7-minute run. Ionization efficiencies of lipid classes vary 10folds in magnitude and great care must be taken in a direct interpretation of raw data. Therefore, the inclusion of internal standards or experimentally determined Response factors (RF) are highly recommended for the conversion of raw abundances into (semi) quantitative data. We have deliberately developed an algorithm for automatic semiquantification of lipid classes by RF. The workflow was tested and validated using a bovine liver extract with satisfactory results. The RF corrected data provide a more representative relative lipid class determination, but also the interpretation of individual lipid species should be performed on RF corrected data. In addition, semiquantification can be improved by using internal or also external standards when more accurate quantitative data are of interest but this requires validation for all new sample types. The workflow established greatly extends the potential of nontarget UHPSFC-MS/MS based analysis.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Lipidômica/métodos , Lipídeos , Espectrometria de Massas em Tandem/métodos , Animais , Bovinos , Galinhas , Ovos/análise , Modelos Lineares , Lipídeos/análise , Lipídeos/química , Fígado/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
Artigo em Inglês | MEDLINE | ID: mdl-33285510

RESUMO

A rapid hybrid solid phase extraction (HybridSPE®) protocol tailored to liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) analysis, was developed for the determination of four thyroid hormones, L-Thyroxine (T4), 3,3',5-triiodo-L-thyronine (T3), 3,3',5'-triiodo-L-thyronine (rT3) and 3,3'-diiodo-L-thyronine (T2) in blood plasma from Glaucous gulls (Larus hyperboreus) and Baikal seals (Phoca sibirica). The use of target analyte specific 13C internal standards allowed quantification to be performed through the standard solvent calibration curves and alleviated the need to perform quantification with matrix match curves. The relative recoveries were 100.0-110.1 % for T4, 99.1-102.2 % for T3, 100.5-108.0 % for rT3, and 100.5-104.6 % for T2. The matrix effects ranged from -1.52 to -6.10 %, demonstrating minor signal suppression during analysis. The method intra-day precision (method repeatability, RSD %, N = 5, k = 1 day) and inter-day precision (method reproducibility, RSD %, N = 10, k = 2 days) at the 1 ng/mL concentration of fortification were 8.54-15.4 % and 15.4-24.8 %, respectively, indicating acceptable chromatographic peak stabilities for all target THs even at trace level concentrations. The method limit of detection (LOD) for T4, T3, rT3 and T2 was 0.17, 0.16, 0.30 and 0.17 ng/mL, respectively. The HybridSPE® protocol was simple and rapid (<1 min) upon application, while the HybridSPE® cartridge did not require (as in classical SPE cartridges) any additional equilibration nor conditioning step prior sample loading. A total of 46 blood plasma samples, 30 samples collected from Glaucous gulls and 16 samples collected from Baikal seals, were analyzed for thyroid hormones to demonstrate the applicability of the developed method in these wildlife species. The concentrations of T4 and T3 in blood plasma from the Glaucous gulls were 5.95-44.2 and 0.37-5.61 ng/mL, respectively, whereas those from Baikal seals were 3.57-46.5 and 0.45-2.07 ng/mL, respectively. In both species, rT3 demonstrated low detection rate, while T2 was not detected. Furthermore, cross-array comparison between the HybridSPE®-LC-MS/MS protocol and an established routine radioimmunoassay (RIA) kit-based method was performed for T4 and T3 concentrations from selected Baikal seal plasma samples.


Assuntos
Charadriiformes/sangue , Cromatografia Líquida/métodos , Focas Verdadeiras/sangue , Espectrometria de Massas em Tandem/métodos , Hormônios Tireóideos/sangue , Animais , Feminino , Limite de Detecção , Masculino , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray
5.
Environ Int ; 137: 105525, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32028175

RESUMO

The exposure of marine mammals to phthalates has received considerable attention due to the ubiquitous occurrence of these pollutants in the marine environment and their potential adverse health effects. The occurrence of phthalate metabolites is well established in human populations, but data is scarce for marine mammals. In this study, concentrations of 17 phthalate metabolites were determined in liver samples collected from one hundred (n = 100) by-caught harbor porpoises (Phocoena phocoena) along the coast of Norway. Overall, thirteen phthalate metabolites were detected in the samples. Monoethyl phthalate (mEP), mono-iso-butyl phthalate (mIBP), mono-n-butyl phthalate (mBP) and phthalic acid (PA) were the most abundant metabolites, accounting for detection rates ≥ 85%. The highest median concentrations were found for mIBP (30.6 ng/g wet weight [w.w.]) and mBP (25.2 ng/g w.w.) followed by PA (7.75 ng/g w.w.) and mEP (5.67 ng/g w.w.). The sum of the median phthalate metabolites concentrations that were found in the majority of samples (detection rates > 50%) indicated that concentrations were lower for porpoises collected along the coastal area of Bodø (Nordland), Lebesby (Finnmark) and Varangerfjord (as compared to other coastal areas); these areas are among the least populated coastal areas but also the most distant (>700 km) from offshore active oil and gas fields. The monomethyl phthalate metabolite (mMP) was detected in 69% of the samples, and to our knowledge, alongside with PA, this is the first report of their occurrence in marine mammals. PA, as the non-specific marker of phthalate exposures, showed a statistically significant negative association with the body mass and length of the harbor porpoises. Among the phthalate metabolites, statistically significant positive associations were found between mBP and mIBP, mMP and mEP, PA and mEP, mIBP and mono(2-ethyl-5-oxohexyl) phthalate (mEOHP), mIBP and mono(2-ethyl-5-hydroxyhexyl) phthalate (mEHHP), mBP and mEHHP, mono-n-nonyl phthalate (mNP) and PA, and between monobenzyl phthalate (mBzP) and mNP. To our knowledge, this is the first study on the biomonitoring of 17 phthalate metabolites in harbor porpoises.


Assuntos
Poluentes Ambientais , Phocoena , Ácidos Ftálicos , Animais , Exposição Ambiental , Humanos , Noruega , Ácidos Ftálicos/metabolismo
6.
Sci Total Environ ; 714: 136674, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31982742

RESUMO

Several laboratory studies have demonstrated that exposure to oil components cause toxicity to copepods, however, this has never been shown in natural populations of copepods. In the present study, we sampled copepods in an area of the North Sea with high density of oil production platforms discharging produced water. Environmental modelling was used to predict produced water and copepod trajectories prior to copepod sampling in situ. To maximise output from a minimal number of field samples, a novel and combined methodology was developed to allow exploitation of the same extract for several purposes; contaminant body burden, lipidomics, and metabolomics analysis. PAH body burdens were low compared to laboratory experiments where correlations between PAH body burden and acute toxicity, reproduction and molecular endpoints had been established. Still, station-specific PAH profiles strongly indicated copepod exposure to PW. NMR metabolomics, focusing on water-soluble metabolites, suggested no correlation between metabolites and stations. Interestingly, lipidomics analyses suggested site-specific fingerprints and profiles displayed for acyl-glycerols and wax esters. Potential effects of produced water exposure on lipid metabolism in copepods cannot be ruled out and deserves more attention. Our study exemplifies the importance of incorporating novel and improved analytical methodologies in environmental monitoring.


Assuntos
Copépodes , Animais , Lipídeos , Mar do Norte , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Água , Poluentes Químicos da Água
7.
Polymers (Basel) ; 10(3)2018 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30966344

RESUMO

We report the synthesis and properties of temperature- and pH-responsive p([NIPAm-co-PEGMA] (core)/[NIPAm-co-AAc] (shell)) nanogels with narrow size distributions, tunable sizes and increased drug loading efficiencies. The core-shell nanogels were synthesized using an optimized two-stage seeded polymerization methodology. The core-shell nanogels show a narrow size distribution and controllable physico-chemical properties. The hydrodynamic sizes, charge distributions, temperature-induced volume phase transition behaviors, pH-responsive behaviors and drug loading capabilities of the core-shell nanogels were investigated using transmission electron microscopy, zeta potential measurements, dynamic light scattering and UV-Vis spectroscopy. The size of the core-shell nanogels was controlled by polymerizing NIPAm with crosslinker poly(ethylene glycol) dimethacrylate (PEGDMA) of different molecular weights (Mn-200, 400, 550 and 750 g/mol) during the core synthesis. It was found that the swelling/deswelling kinetics of the nanogels was sharp and reversible; with its volume phase transition temperature in the range of 40⁻42 °C. Furthermore, the nanogels loaded with l-3,4-dihydroxyphenylalanine (L-DOPA), using a modified breathing-in mechanism, showed high loading and encapsulation efficiencies, providing potential possibilities of such nanogels for biomedical applications.

8.
Br J Cancer ; 113(12): 1712-9, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26633561

RESUMO

BACKGROUND: An individualised risk-stratified screening for prostate cancer (PCa) would select the patients who will benefit from further investigations as well as therapy. Current detection methods suffer from low sensitivity and specificity, especially for separating PCa from benign prostatic conditions. We have investigated the use of metabolomics analyses of blood samples for separating PCa patients and controls with benign prostatic hyperplasia (BPH). METHODS: Blood plasma and serum samples from 29 PCa patient and 21 controls with BPH were analysed by metabolomics analysis using magnetic resonance spectroscopy, mass spectrometry and gas chromatography. Differences in blood metabolic patterns were examined by multivariate and univariate statistics. RESULTS: By combining results from different methodological platforms, PCa patients and controls were separated with a sensitivity and specificity of 81.5% and 75.2%, respectively. CONCLUSIONS: The combined analysis of serum and plasma samples by different metabolomics measurement techniques gave successful discrimination of PCa and controls, and provided metabolic markers and insight into the processes characteristic of PCa. Our results suggest changes in fatty acid (acylcarnitines), choline (glycerophospholipids) and amino acid metabolism (arginine) as markers for PCa compared with BPH.


Assuntos
Biomarcadores Tumorais/sangue , Hiperplasia Prostática/sangue , Neoplasias da Próstata/sangue , Idoso , Estudos de Casos e Controles , Diagnóstico Diferencial , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Hiperplasia Prostática/diagnóstico , Neoplasias da Próstata/diagnóstico , Curva ROC
9.
J Neurochem ; 101(6): 1694-700, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17286586

RESUMO

An increase in the concentration of glycerol in the ischemic brain is assumed to reflect degradation of phospholipids of plasma membranes. However, glycerol could, theoretically, be formed from glucose, which after glycolytic conversion to dihydroxyacetone phosphate, could be converted to glycerol-3-phosphate and hence to glycerol. We show here that (13)C-labeled glycerol accumulate in incubation media of cultured cerebellar granule cells and astrocytes incubated with [(13)C]glucose, 3 mmol/L, demonstrating the formation of glycerol from glucose. Co-incubation of cerebellar granule cells with kainate, 50 micromol/L, led to increased glucose metabolism and increased accumulation of [(13)C]glycerol. Accumulation of [(13)C]glycerol and its precursor, [(13)C]glycerol-3-phosphate, was evident in brain, but not in serum, of kainate-treated rats that received [U-(13)C]glucose, 5 micromol/g bodyweight, intravenously and survived for 5 min. Global ischemia induced by decapitation also caused accumulation of [(13)C]glycerol and [(13)C]glycerol-3-phosphate. These results show that glycerol can be formed from glucose in brain; they also demonstrate the existence of a cerebral glycerol-3-phosphatase activity. Ischemia-induced increases in brain glycerol may, in part, reflect an altered metabolism of glucose, in which glycerol formation, like lactate formation, acts as a redox sink.


Assuntos
Isquemia Encefálica/fisiopatologia , Encéfalo/metabolismo , Glucose/metabolismo , Glicerol/metabolismo , Ácido Caínico/farmacologia , Animais , Astrócitos/metabolismo , Encéfalo/citologia , Isótopos de Carbono , Células Cultivadas , Cerebelo/citologia , Cerebelo/metabolismo , Glicerofosfatos/biossíntese , Masculino , Redes e Vias Metabólicas , Ressonância Magnética Nuclear Biomolecular , Fosfolipídeos/metabolismo , Ratos , Ratos Wistar
10.
J Neurochem ; 101(3): 806-14, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17286595

RESUMO

In propionic acidemia, propionate acts as a metabolic toxin in liver cells by accumulating in mitochondria as propionyl-CoA and its derivative, methylcitrate, two tricarboxylic acid cycle inhibitors. Little is known about the cerebral metabolism of propionate, although clinical effects of propionic acidemia are largely neurological. We found that propionate was metabolized oxidatively by glia: [3-(14)C]propionate injected into mouse striatum or cortex, gave a specific activity of glutamine that was 5-6 times that of glutamate, indicating metabolism in cells that express glutamine synthetase, i.e., glia. Further, cultured cerebellar astrocytes metabolized [3-(14)C]propionate; cultured neurons did not. However, both cultured cerebellar neurons and astrocytes took up [3H]propionate, and propionate exposure increased histone acetylation in cultured neurons and astrocytes as well as in hippocampal CA3 pyramidal neurons of wake mice. The inability of neurons to metabolize propionate may be due to lack of mitochondrial propionyl-CoA synthetase activity or transport of propionyl residues into mitochondria, as cultured neurons expressed propionyl-CoA carboxylase, a mitochondrial matrix enzyme, and oxidized isoleucine, which becomes converted into propionyl-CoA intramitochondrially. The glial metabolism of propionate suggests astrocytic vulnerability in propionic acidemia when intramitochondrial propionyl-CoA may accumulate. Propionic acidemia may alter both neuronal and glial gene expression by affecting histone acetylation.


Assuntos
Histonas/metabolismo , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Propionatos/farmacologia , Acetilação/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Encéfalo/metabolismo , Células Cultivadas , Cerebelo/citologia , Feminino , Isótopos/farmacocinética , Camundongos , Modelos Biológicos , Propionatos/metabolismo , Propionatos/farmacocinética , Ratos , Fatores de Tempo
11.
Neurotoxicology ; 28(1): 13-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17087995

RESUMO

Organophosphates, such as the nerve gas soman, cause inhibition of acetylcholine esterase, accumulation of acetylcholine in synaptic clefts, and excessive activation of cholinergic receptors, causing central nervous symptoms such as tremor and seizures. Soman-poisoned animals have low brain levels of ATP, indicating that energy demand is greater than energy supply. We investigated whether soman poisoning is accompanied by an increased brain metabolism of glucose, as can be inferred from the accumulation of radiolabeled 2-deoxyglucose found in previous studies, or whether soman poisoning entails impairment of cerebral energy metabolism. We performed 13C nuclear magnetic resonance spectroscopy on brain extracts from soman-poisoned mice (160 microg/kg; 1 LD50) that had been dosed with 13C-labeled glucose or pyruvate intravenously. Formation of 13C-labeled glutamate, GABA and glutamine from [1-(13)C]glucose was reduced by approximately 30% in awake, soman-intoxicated animals, but formation of these amino acids from [3-(13)C]pyruvate was not different in soman-intoxicated animals and controls. These results suggest that soman intoxication entails inhibition of glycolysis, but not of tricarboxylic acid cycle activity in the brain. However, when brain metabolism was depressed by a sedative dose of diazepam (5 mg/kg) soman intoxication caused increased metabolism of 13C-labeled glucose. The latter finding shows that the soman-poisoned brain has a high energy requirement even during anticonvulsant therapy. We conclude that metabolic inhibition, as seen in awake, soman-intoxicated animals, may lower seizure threshold and contribute to soman-related neurodegeneration and lethality.


Assuntos
Química Encefálica/efeitos dos fármacos , Inibidores da Colinesterase/intoxicação , Glucose/metabolismo , Ácido Pirúvico/metabolismo , Soman/intoxicação , Animais , Ciclo do Ácido Cítrico/efeitos dos fármacos , Desoxiglucose/metabolismo , Eletroencefalografia , Feminino , Glicólise/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Camundongos
12.
J Neurochem ; 95(1): 284-93, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16181432

RESUMO

Pyruvate given in large doses may be neuroprotective in stroke, but it is not known to what degree the brain metabolizes pyruvate. Intravenous injection of [3-13C]pyruvate led to dose-dependent labelling of cerebral metabolites so that at 5 min after injection of 18 mmoles [3-13C]pyruvate/kg (2 g sodium pyruvate/kg), approximately 20% of brain glutamate and GABA were labelled, as could be detected by 13C nuclear magnetic resonance spectrometry ex vivo. Pyruvate, 9 mmoles/kg, was equivalent to glucose, 9 mmoles/kg, as a substrate for cerebral tricarboxylic acid (TCA) cycle activity. Inhibition of the glial TCA cycle with fluoroacetate did not affect formation of [4-13C]glutamate or [2-13C]GABA from [3-13C]pyruvate, but reduced formation of [4-13C]glutamine by 50%, indicating predominantly neuronal metabolism of exogenous pyruvate. Extensive formation of [3-13C]lactate from [2-13C]pyruvate demonstrated reversible carboxylation of pyruvate to malate and equilibration with fumarate, presumably in neurones, but anaplerotic formation of TCA cycle intermediates from exogenous pyruvate could not be detected. Too rapid injection of large amounts of pyruvate led to seizure activity, respiratory arrest and death. We conclude that exogenous pyruvate is an excellent energy substrate for neurones in vivo, but that care must be taken to avoid the seizure-inducing effect of pyruvate given in large doses.


Assuntos
Encéfalo/metabolismo , Piruvatos/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Sangue/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Relação Dose-Resposta a Droga , Eletroencefalografia , Metabolismo Energético , Jejum/metabolismo , Feminino , Fluoracetatos/farmacologia , Glucose/administração & dosagem , Glucose/metabolismo , Injeções Intravenosas , Ácido Láctico/metabolismo , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Malatos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Piruvatos/administração & dosagem , Convulsões/induzido quimicamente , Convulsões/diagnóstico , Fatores de Tempo
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