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1.
J Forensic Sci ; 67(5): 1962-1970, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35943118

RESUMO

Within post-conflict communities, attempts to identify and repatriate unidentified and missing individuals poses a difficult task. As current forensic strategies commonly lack the capacity to provide region of origin assessments, forensic anthropologists/investigators are often unable to identify sources of DNA for kinship analysis. Using Thermal Ionization Mass Spectrometry (TIMS), hair samples from 10 volunteers were used to assess the variation in strontium isotope ratios (87 Sr/86 Sr) between extant people in Guatemala City and Coban; with a leach (external) and digest (dietary) signal analyzed for each sample. A two-way anova demonstrated that the difference between 87 Sr/86 Sr of Guatemala City and Coban was statistically significant (F [1, 16] = 259.839, p < 0.05), with no statistically significant differences observed between leach and digest 87 Sr/86 Sr (F [1,16] = 4.319, p = 0.054). Overall, individuals from Coban demonstrate 87 Sr/86 Sr comparable to previously recorded baseline values, demonstrating a minimal change in diet which is reflected in associated surveys. Volunteers from Guatemala City, however, show a marked shift in 87 Sr/86 Sr away from predicted values highlighting the potential influence of imported goods. The results here highlight the applicability of 87 Sr/86 Sr in hair to serve as a potential tool to support the identification of unknown individuals in Guatemala in a forensic context.


Assuntos
Monensin , Isótopos de Estrôncio , Cidades , Cabelo/química , Humanos , Espectrometria de Massas/métodos , Monensin/análise , Estrôncio/análise , Isótopos de Estrôncio/análise
2.
J Environ Manage ; 277: 111500, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33069155

RESUMO

There are thousands of disused and abandoned mining sites around the world with substantial accumulations of exposed mine spoil materials that pose a direct threat to their surrounding environment. Management of such sites, and neutralisation of the environmental threats they pose, is therefore extremely important and is an issue of global significance. Low cost management and remediation strategies need to be developed because many abandoned mine sites are in remote and/or economically challenged areas. One promising option is the incorporation of biochar into spoil materials, which has the potential to immobilise leachable toxic constituents and facilitate revegetation and thereby stabilisation of spoil heaps. This study investigated the capacity of readily available biochar materials made from wheat and rice waste products to immobilise and retain key metallic contaminants Pb and Zn from solution, and also investigated the utility of biochar application for remediating mine spoil heaps from different mine types in terms of facilitating establishment of vegetation coverage and minimising porewater element mobility within spoil heaps. The results demonstrated the high sorption capacity of the biochars (typically >97% of Pb or Zn in solution) and their ability to retain the metals despite an active desorption procedure (>93% of sorbed Pb retained and >75% of sorbed Zn). The remediation trial revealed that biochar application increased plant yield and decreased plant assimilation of many potentially toxic elements and also decreased spoil porewater concentrations of Al, Cd, Pb and Zn in most cases. In some spoil types investigated biochar addition also significantly decreased porewater concentrations of As (e.g. from ~30 mg/L to ~5 mg/L), demonstrating its potential utility for low cost environmental remediation across a range of mine spoil types.


Assuntos
Recuperação e Remediação Ambiental , Metais Pesados , Poluentes do Solo , Carvão Vegetal , Metais Pesados/análise , Mineração , Solo , Poluentes do Solo/análise
3.
Environ Toxicol Chem ; 39(6): 1277-1291, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32135571

RESUMO

During clarification processes of raw water, a vast amount of by-product known as "drinking water-treatment residuals" (WTRs) are produced, being principally composed of hydroxides of the Al or Fe salts added during water treatment plus the impurities they remove. Aluminum-based (Al-WTR) and iron-based (Fe-WTR) materials were applied at 10% w/w to degraded, bare (unvegetated) soils from a restored coal mining site in central England (pH <3.9) to study their potential amelioration effects on earthworm mortality, biomass yield of seedling plants, and element concentrations in plant tissues, earthworm tissues, and soil solutions. A separate treatment with agricultural lime was also conducted for comparison to evaluate whether any observed improvements were attributable to the liming capacity of the WTRs. After completion of the trials, all samples were subjected to a wet-dry cycle, and the experiments were repeated (i.e., simulating longer-term effects in the field). Both types of WTRs significantly increased the biomass of plants, and in some treatments, survival of earthworms was also enhanced compared to nonamended soils. Excess plant tissue element concentrations and element concentrations in soil solutions were reduced in amended soils. The implications are that adding WTRs to mining-impacted soils is a potentially viable, sustainable, and low-cost remediation method that could be used globally to improve the soil condition. Environ Toxicol Chem 2020;39:1277-1291. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.


Assuntos
Recuperação e Remediação Ambiental/métodos , Mineração , Oligoquetos/efeitos dos fármacos , Plantas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Solo/química , Água/química , Irrigação Agrícola , Alumínio/química , Animais , Biomassa , Ecotoxicologia , Inglaterra , Ferro/química , Plantas/metabolismo , Soluções , Purificação da Água/métodos
4.
Xenobiotica ; 49(11): 1352-1359, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30557119

RESUMO

1. The metabolic fate and urinary excretion of 2-bromophenol, a phenolic metabolite of bromobenzene, was investigated in male Sprague-Dawley rats following single intraperitoneal doses at either 0, 100, or 200 mg/kg.2. Urine was collected for seven days and samples analysed using 1 H NMR spectroscopy, inductively coupled plasma (ICP)MS, and UPLC-MS.3. 1 H NMR spectroscopy of the urine samples showed that, at these doses, 2-bromophenol had little effect on endogenous metabolite profiles, supporting histopathology and clinical chemistry data, which showed no changes associated with the administration of 2-bromophenol in this study.4. The use of ICP-MS provided a means for the selective detection and quantification of bromine-containing species and showed that between 15 and 30% of the dose was excreted via the urine over 7 days of the study for both the 100 and 200 mg doses, respectively.5. The bulk of the excretion of Br-containing material had occurred by 8 h post administration. UPLC-MS of urine revealed a number of metabolites of 2-bromophenol, with 2-bromophenol glucuronide and 2-bromophenol sulphate identified as the major species. A number of minor hydroxylated metabolites were also detected as their glucuronide, sulphate, or O-methyl conjugates. There was no evidence for the production of reactive metabolites.


Assuntos
Substâncias Perigosas/toxicidade , Fenóis/toxicidade , Testes de Toxicidade , Animais , Masculino , Ratos , Ratos Sprague-Dawley
5.
Anal Chem ; 90(12): 7489-7494, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29808994

RESUMO

Metabonomic techniques have been used to discover subtle differences in the small-molecule profiles of chicken eggs, which could help to combat fraud within the egg industry. High-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-Q-ToF-MS) was used to obtain profiles of the small molecules present in the yolks of chicken eggs stored for different lengths of time. Statistical analysis, including the use of XCMS Online and further exploratory statistics, was able to uncover differences in the abundances of several of the small molecules found in these egg yolks. One of these small molecules was identified through the use of METLIN and MS/MS analysis as choline. A targeted study was then carried out over a longer storage period, using the same instrumentation and analytical techniques, in order to observe how the concentration of choline in egg yolk changes over a longer period of time.


Assuntos
Ovos/análise , Armazenamento de Alimentos , Metabolômica , Bibliotecas de Moléculas Pequenas/análise , Animais , Galinhas , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Bibliotecas de Moléculas Pequenas/metabolismo , Fatores de Tempo
6.
Anal Chem ; 89(22): 12131-12136, 2017 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-29068675

RESUMO

Metabonomic profiling techniques, with established quality control methods, have been used to detect subtle metabolic differences in tissue that could aid in the discovery of fraud within the food industry. Liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) was utilized to acquire metabolic profiles of muscle, heart, and liver tissue from normally slaughtered and dead on arrival chickens. A workflow including XCMS Online for data processing and robust confirmatory statistics was used in order to differentiate between the two sample types. It was found that normally slaughtered and dead on arrival chicken can be differentiated based on the metabolic profile and multivariate analysis. Markers were found to be significantly different between the two sample types in all samples. With the use of the METLIN database and MS/MS analysis of chemical standards, sphingosine was identified as a marker in the muscle tissue samples which may offer potential for the detection of fraudulently processed chicken meat. The approach taken in this work has shown that it is possible to apply the described workflows to food fraud problems, with an objective of identifying key markers that could be investigated further to determine their usefulness for fraud detection.


Assuntos
Morte , Carne/análise , Metabolômica/métodos , Matadouros , Animais , Galinhas , Cromatografia Líquida , Espectrometria de Massas , Fatores de Tempo
7.
Anal Chem ; 88(8): 4311-7, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-26965316

RESUMO

Novel solid-contact iodide-selective electrodes based on covalently attached 1,2,3 triazole ionic liquid (IL) were prepared and investigated in this study. Triazole-based IL moieties were synthesized using click chemistry and were further copolymerized with lauryl methacrylate via a simple one-step free radical polymerization to produce a "self-plasticized" copolymer. The mechanical properties of the copolymer are suitable for the fabrication of plasticizer-free ion-selective membrane electrodes. We demonstrate that covalently attached IL moieties provide adequate functionality to the ion-selective membrane, thus achieving a very simple, one-component sensing membrane. We also demonstrate that the presence of iodide as the counterion in the triazole moiety has direct influence on the membrane's functionality. Potentiometric experiments revealed that each electrode displays high selectivity toward iodide anions over a number of inorganic anions. Moreover, the inherent presence of the iodide in the membrane reduces the need for conditioning. The nonconditioned electrodes show strikingly similar response characteristics compared to the conditioned ones. The electrodes exhibited a near Nernstian behavior with a slope of -56.1 mV per decade across a large concentration range with lower detection limits found at approximately 6.3 × 10(-8) M or 8 ppb. These all-solid-state sensors were utilized for the selective potentiometric determination of iodide ions in artificial urine samples in the nanomolar concentration range.


Assuntos
Iodetos/urina , Líquidos Iônicos/química , Triazóis/química , Eletrodos , Humanos , Líquidos Iônicos/síntese química , Estrutura Molecular , Plastificantes , Polimerização , Potenciometria
8.
Rapid Commun Mass Spectrom ; 27(22): 2539-2545, 2013 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-24123642

RESUMO

RATIONALE: Metabonomic studies use complex biological samples (blood plasma/serum, tissues, etc.) that when analysed with high-performance liquid chromatography/mass spectrometry (HPLC/MS) or nuclear magnetic resonance (NMR) generate profiles that may contain many thousands of features. These profiles can be difficult to interpret with the majority of the features contributing little to the study. As such there is an argument for the development of techniques that can simplify the problem by targeting particular classes of compounds. METHODS: In this study ultra-performance liquid chromatography/inductively coupled plasma mass spectrometry (UPLC/ICP-MS) was used to profile tumour tissue and plasma samples for phosphorus- and sulfur-containing metabolites. These samples were xenograft tumours (derived from breast, lung and colon cell lines) and plasma obtained from nude mice. Plasma was also obtained from non-tumour-bearing mice as a control. Due to isobaric interferences this method took advantage of the dynamic reaction cell within the ICP-MS system to react the phosphorus and sulfur ions with oxygen. The PO+ and SO+ ions were then monitored free of interferences. The total phosphorus and sulfur within each sample was also recorded using flow injection ICP-MS. A robust quality control system based on pooled sample replicate analysis was used throughout the study. RESULTS: Determination of the total phosphorus and sulfur content of each sample was sufficient in itself for statistical differentiation between the majority of the cell lines analysed. Subsequent reversed-phase chromatographic profiling of the organic tumour and plasma extracts revealed the presence of a number of well-retained phosphorus-containing compounds that showed tumour-specific profiles. Reversed-phase profiling was not suitable for the sulfur-containing compounds which eluted with the solvent front. CONCLUSIONS: This study has shown the potential use of UPLC/ICP-MS to differentiate between tumour cell lines, using both plasma and tumour tissue samples, based solely on metabolites that contain phosphorus or sulfur. Whilst further work is required to identify these compounds this methodology shows the ability of the described methods to provide targets for future biomarker discovery studies. Copyright © 2013 John Wiley & Sons, Ltd.

9.
Mol Biosyst ; 7(4): 1149-57, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21243133

RESUMO

In this preliminary study UPLC-ICP-MS has been utilized to profile a range of different bio-fluids and tissue extracts for sulfur and phosphorus-containing metabolites. Particular attention has been given to the livers, plasma and urine from lean and obese Zucker rats, with a view to differentiating between them based solely on their respective sulfur or phosphorus profiles and/or their total sulfur and phosphorus content. In addition, bile and tumour extracts have been analysed to observe the nature of their profiles. To the best of our knowledge this is the first time ICP-MS has been used in a non-targeted metabonomic study. Results have shown lower limits of quantification for sulfur and phosphorus methods of 0.25 and 0.15 ng on column with CVs of 14.7% and 10.9% respectively. Total phosphorus analysis of the Zucker rat aqueous liver extracts, plasma and urine has shown the pattern of phosphorus concentrations to be statistically significantly different in the lean and obese Zucker rats. Chromatographic separation of the Zucker rat organic liver extracts and plasma allowed further differentiation between the lean and obese rats using their phosphorus profiles alone. In conclusion, this preliminary study has shown the potential of UPLC-ICP-MS to quantitatively discriminate between different species biofluids, fluids and tissues based solely on their phosphorus or sulfur concentrations and/or metabolomes.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida , Espectrometria de Massas , Fósforo/análise , Enxofre/análise , Animais , Bile/química , Cães , Feminino , Humanos , Limite de Detecção , Fígado/química , Masculino , Camundongos , Camundongos Nus , Neoplasias/química , Fósforo/sangue , Fósforo/urina , Ratos , Ratos Wistar , Ratos Zucker , Sensibilidade e Especificidade , Enxofre/sangue , Enxofre/urina
10.
Rapid Commun Mass Spectrom ; 24(7): 927-32, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20196195

RESUMO

This work aimed to develop and validate a NANOGold based assay, quantified using inductively coupled plasma mass spectrometry (ICP-MS), for the detection of human vascular endothelial growth factor (hVEGF) in serum. The initial assay range based on calibration standards was 62.5-2000 pg/mL with a detection limit of approximately 30 pg/mL. After validation using spiked validation controls, a quantification range between 175 and 1928 pg/mL was obtained. The inter-assay precision was between 2.3 and 18.9% with accuracy between -8.8 and -3.1%. Additional performance parameters, including dilutional linearity, matrix specificity and time-factored drift, were within +/-20%, as defined by the validation acceptance criteria for the validation of macromolecule immunoassays used within our clinical environment. Serum samples from healthy donors were analysed to determine the endogenous levels of VEGF present; these ranged from 164 to 580 pg/mL with a mean of 273 pg/mL. The intra- and inter-assay precision obtained from the healthy donor samples were 1.3-10.7% and 4.2-17.5%, respectively. This demonstration of a validated immunoassay opens further possibilities, utilising the simultaneous detection capabilities of ICP-MS for the detection of multiple analytes in a single validated immunoassay, for routine use within a clinical environment.


Assuntos
Ouro/química , Imuno-Histoquímica/métodos , Espectrometria de Massas/métodos , Nanopartículas Metálicas/química , Fator A de Crescimento do Endotélio Vascular/sangue , Humanos , Modelos Lineares , Reprodutibilidade dos Testes , Fatores de Tempo
11.
Plant Dis ; 83(3): 240-246, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30845501

RESUMO

The efficacy of sodium tetrathiocarbonate (STTC or Enzone 31.8%, a liquid formulation that releases carbon disulfide) and the demethylation inhibiting (DMI) fungicide propiconazole (Alamo 1.1EC) was evaluated for management of Armillaria root rot of almond grown on Lovell peach rootstock. After 12 months, pre-/post-plant STTC (189 liters of 3,850 and 500 mg/liter/3 m2 treatment site, respectively) or tarped pre-plant methyl bromide (Dowfume 98%, 454 g a.i./3 m2) soil fumigation treatments significantly (P < 0.05) reduced the recovery of Armillaria mellea from naturally infected root segments at 0.3 and 1.2 m soil depths, compared with control sites. Tarped methyl bromide treatments eradicated the fungus from infested root segments at both depths; however, nontarped sites significantly reduced the recovery only at the 1.2 m depth. Pre-plant STTC (189 liters of 3,850 mg/liter/3 m2) reduced the recovery of the fungus but was not as effective as the pre-/post-plant STTC treatment. Recovery of the fungus in post-plant treatments with STTC (189 liters of 500 mg/liter/3 m2) was not significantly (P > 0.05) different from control sites. Additionally, mortality of almond tree replants from phytotoxicity was significantly higher in post-plant applications of STTC, compared with the other treatments or with the control trees. A gel formulation of 31.8% STTC (1,800 ml of 318,000 mg of STTC per liter per tree stump) applied in wells that were drilled into tree stumps eradicated the fungus from trunk and primary roots but not secondary or tertiary roots, whereas liquid formulations of STTC and metam-sodium (Vapam - 32.7% sodium N-methyldithiocarbamate) eradicated the fungus from only trunks but not roots. Treatments with STTC (189 liters of 500 mg/liter/3 m2) were not effective in preventing mortality of A. mellea-infected, mature, 7- to 8-year-old almond trees. Propiconazole (Alamo 1.1EC) was shown to be toxic to mycelial growth of A. mellea grown on potato dextrose agar with an EC50 value of 0.15 mg/liter. Therapeutic, passive injections of propiconazole into 7- to 8-year-old almond trees (Lovell peach rootstock) were successful in reducing mortality of infected trees during two growing seasons, compared with infected control trees treated with water.

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