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1.
Biol Trace Elem Res ; 201(8): 3688-3696, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36394794

RESUMO

Exposure to heavy metals represents one of the most important risk factors for the health of incinerator workers. Indeed, heavy metals can determine increased generation of reactive oxygen species (ROS). In this work, we introduced the use of transcription profiling of detoxifying genes, involved in redox balance and genome integrity, as a highly sensitive assay of heavy metal exposure and subsequent oxidative stress. For this purpose, blood mRNA levels of OGG1, ST13, NQO1 and MT1A genes, as well as urinary concentrations of nine heavy metals and the oxidized base 8-OHdG of 49 subjects (26 controls and 23 employees in the waste-to-energy plant of San Zeno, Arezzo, Italy) were determined. No significant difference between the two populations was observed, thus highlighting, as far as the biomarkers analysed are concerned, the absence of occupational exposure to heavy metals and systemic oxidative stress induction in the workers of the waste-to-energy plant of San Zeno. Correlation analyses underline a close association between heavy metals exposure and changes in expression levels of a number of genes, even at low exposure doses, thus remarking the greater capacity of detection of transcription profiling compared to other biomarkers and the importance of its introduction in future human biomonitoring programs.


Assuntos
Metais Pesados , Exposição Ocupacional , Humanos , Monitoramento Biológico , Metais Pesados/análise , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Estresse Oxidativo/genética , Plantas , Perfilação da Expressão Gênica
2.
PLoS One ; 17(11): e0278116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36417420

RESUMO

In 2016, a Stollhof-type copper hoard was found during an excavation in Magyaregres, Hungary. It was placed in a cooking pot, and deposited upside down within the boundaries of an Early Copper Age settlement. Similar hoards dating to the end of the 5th millennium BCE are well-known from Central Europe, however, this hoard represents the only one so far with thoroughly documented finding circumstances. The hoard contained 681 pieces of copper, 264 pieces of stone and a single Spondylus bead, along with 19 pieces of small tubular spiral copper coils, three spiral copper bracelets, and two large, spectacle spiral copper pendants. Until now, information on the provenance of raw materials and how such copper artefacts were manufactured has not been available. The artefacts were studied under optical microscopes to reveal the manufacturing process. Trace elemental composition (HR-ICP-MS) and lead isotope ratios (MC-ICP-MS) were measured to explore the provenance of raw materials. The ornaments were rolled or folded and coiled from thin sheets of copper using fahlore copper probably originating from the Northwestern Carpathians. A complex archaeological approach was employed to reveal the provenance, distribution and the social roles the ornaments could have played in the life of a Copper Age community. Evidence for local metallurgy was lacking in contemporaneous Transdanubian sites, therefore it is likely that the items of the hoard were manufactured closer to the raw material source, prior to being transported to Transdanubia as finished products. The method of deposition implies that such items were associated with special social contexts, represented exceptional values, and the context of deposition was also highly prescribed. The Magyaregres hoard serves as the first firm piece of evidence for the existence of a typologically independent Central European metallurgical circle which exploited the raw material sources located within its distribution.


Assuntos
Arqueologia , Tecnologia , Hungria , Artefatos , Metalurgia
3.
J Environ Radioact ; 225: 106426, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32977166

RESUMO

For the first time, vanadium of biological origin, extracted from centrifugal fraction of vanadium-storing blood cells of the Ascidia sydneiensis samea species, was characterized as regards its isotopic composition and content of natural radioactive elements potassium (K), thorium (Th) and uranium (U). The natural abundance of vanadium isotopes has been confirmed with high accuracy, thus excluding a possible selectivity within bio-chemical reactions of vanadium concentration in blood cells from seawater. A large potassium concentration (up to 5500 × 10-6 g g-1) was found in the blood cell samples. The concentration of thorium was determined to be about 30 × 10-9 g g-1, while the uranium concentration was about 150 × 10-9 g g-1. Hence, a highly efficient two-stage purification approach with a total vanadium recovery of better than 70% was developed and applied. The final concentrations of K < 100 × 10-6 g g-1 and of U/Th < 0.5 × 10-9 g g-1 in the purified vanadium-containing samples were achieved. Vanadium extracted from centrifugal fraction of vanadium-storing blood cells after two-stage purification approach could be utilized in various applications, where a high chemical purity compound is required. However, to be used as a source of radiopure vanadium in ultra-low-background experiment aimed to search for 50V beta decay, it should be further purified by Electron Beam Melting against residual potassium.


Assuntos
Urocordados/fisiologia , Vanádio/análise , Animais , Física , Monitoramento de Radiação , Urânio , Urocordados/metabolismo , Vanádio/metabolismo
4.
J Mass Spectrom ; 55(11): e4595, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32677103

RESUMO

Seventy-six samples of saffron were analysed through inductively coupled plasma-mass spectrometry (ICP-MS) and stable isotope ratio analysis. The dataset was formed by 67 samples harvested in different areas of Italy, Morocco and Iran, and nine samples purchased in the Italian market. For the first time, 42 elements and five stable isotopes (δ13 C, δ15 N, δ34 S, δ2 H and δ18 O) were considered to carry out the discrimination of the samples on the basis of their geographical origin. Combined ICP-MS and isotopic composition data turned out to be a useful tool for the geographical discrimination of saffron among predefined cultivation sites. K, Cr, Mn, Ni, Zn, Rb, Sr, Mo, Cs, Nd, Eu, Pb, δ13 C, δ15 N, δ34 S and δ2 H were identified as the significant variables in geographical discrimination. Moreover, the class models generated for saffron cultivated in two specific areas of Central Italy exhibited 100% specificity for Moroccan, Iranian and commercial samples and a high specificity (83% and 84%) for the saffron samples cultivated in other, although close, Italian sites.

5.
Nanomaterials (Basel) ; 10(5)2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384606

RESUMO

Synthetic amorphous silica (SAS), manufactured in pyrogenic or precipitated form, is a nanomaterial with a widespread use as food additive (E 551). Oral exposure to SAS results from its use in food and dietary supplements, pharmaceuticals and toothpaste. Recent evidence suggests that oral exposure to SAS may pose health risks and highlights the need to address the toxic potential of SAS as affected by the physicochemical characteristics of the different forms of SAS. For this aim, investigating SAS toxicokinetics is of crucial importance and an analytical strategy for such an undertaking is presented. The minimization of silicon background in tissues, control of contamination (including silicon release from equipment), high-throughput sample treatment, elimination of spectral interferences affecting inductively coupled plasma mass spectrometry (ICP-MS) silicon detection, and development of analytical quality control tools are the cornerstones of this strategy. A validated method combining sample digestion with silicon determination by reaction cell ICP-MS is presented. Silica particles are converted to soluble silicon by microwave dissolution with mixtures of HNO3, H2O2 and hydrofluoric acid (HF), whereas interference-free ICP-MS detection of total silicon is achieved by ion-molecule chemistry with limits of detection (LoDs) in the range 0.2-0.5 µg Si g-1 for most tissues. Deposition of particulate SiO2 in tissues is assessed by single particle ICP-MS.

6.
Nanomaterials (Basel) ; 8(7)2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29996541

RESUMO

Iodoxybenzoic acid (IBX) supported multi walled carbon nanotube (MWCNT) derivatives have been prepared as easily recyclable solid reagents. These compounds have been shown to be able to mimic the alcohol dehydrogenases and monooxygenases promoted oxidation of aromatic alcohols to corresponding aldehydes. Their reactivity was found to be dependent on the degree of functionalization of MWCNTs as well as from the chemical properties of the spacers used to bind IBX on the surface of the support. Au-decorated MWCNTs and the presence of longer spacers resulted in the optimal experimental conditions. A high conversion of the substrates and yield of desired products were obtained.

7.
Food Chem ; 157: 485-9, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24679808

RESUMO

27 Saffron spices produced in three Italian regions, Abruzzo (L'Aquila), Umbria and Sardinia, were analysed by inductively coupled plasma-mass spectrometry to test potentiality of mineral composition for geographical traceability. A linear discriminant analysis (LDA) based on concentrations of 12 selected elements, Li, B, Na, Ga, Rb, Sr, Zr, Nb, Cs, Ba, Sm, and Hf, allows more than 80% of correct predictions in leave-one cross-validation. Four elements (B, Na, Sr and Rb), identified by step-wise LDA, provide more than 90% of correct predictions. Moreover, saffron spices cultivated in Sardinia and Central Italy can be distinguished under more severe validation conditions (20% of samples in the prediction set). In summary, mineral composition results a promising indicator of saffron geographical origin.


Assuntos
Crocus/química , Espectrometria de Massas/métodos , Geografia , Itália , Análise Multivariada
8.
Metallomics ; 4(12): 1321-32, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23151739

RESUMO

Metal dyshomeostasis plays a crucial role in promoting several neurodegenerative diseases including Alzheimer's disease (AD), a condition that has been linked to deregulation of brain levels of Al, Fe, Mn, Cu, and Zn. Thus, quantitative multi-element profiling of brain tissues from AD models can be of great value in assessing the pathogenic role of metals as well as the value of therapeutic interventions aimed at restoring metal homeostasis in the brain. In this study, we employed low resolution inductively coupled plasma mass spectrometry (ICP-MS) to evaluate levels of ultra-trace, trace, and major elements in brains and cerebella of 3xTg-AD mice, a well characterized transgenic (Tg) AD model. This method is based on alternated cool and hot plasma ICP-MS. The essay fulfilled analytical requirements for the quantification of 14 elements in the Central Nervous System (CNS) of our Tg model. Quantification of Li, Al, Cr, and Co, a procedure that requires a pre-concentration step, was validated by high resolution ICP-MS. Changes in element profiles occurring in 3xTg-AD mice were compared to the ones observed in wild type (WT) mice. We also investigated variations in element profiles in 3xTg-AD mice receiving a long-term (17 months) dietary supplementation of Zn. Our data indicate that, compared to WT animals, 3xTg-AD mice displayed signs of altered brain metal homeostasis. We also found that long-term Zn administration promoted decreased brain levels of some metals (K, Ca, and Fe) and restored levels of Al, Cr, and Co to values found in WT mice.


Assuntos
Doença de Alzheimer/dietoterapia , Doença de Alzheimer/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Oligoelementos/metabolismo , Zinco/administração & dosagem , Alumínio/metabolismo , Doença de Alzheimer/genética , Animais , Química Encefálica , Cromo/metabolismo , Cobalto/metabolismo , Suplementos Nutricionais , Modelos Animais de Doenças , Homeostase/efeitos dos fármacos , Lítio/metabolismo , Masculino , Espectrometria de Massas/métodos , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fatores de Tempo , Oligoelementos/análise
9.
J Environ Radioact ; 101(1): 45-50, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19726113

RESUMO

Monitoring of chemical and physical groundwater parameters has been carried out worldwide in seismogenic areas with the aim to test possible correlations between their spatial and temporal variations and strain processes. Uranium (U) groundwater anomalies were observed during the preparation phases of the recent L'Aquila earthquake of 6th April 2009 in the cataclastic rocks near the overthrust fault crossing the deep underground Gran Sasso National Laboratory. The results suggest that U may be used as a potential strain indicator of geodynamic processes occurring before the seismic swarm and the main earthquake shock. Moreover, this justifies the different radon patterns before and after the main shock: the radon releases during and after the earthquake are much than more during the preparatory period because the process does not include only the microfracturing induced by stress-strain activation, but also radon increases accompanying groundwater U anomalies.


Assuntos
Terremotos , Água Doce/química , Monitoramento de Radiação/métodos , Urânio/análise , Poluentes Químicos da Água/análise , Itália , Cinética , Radônio/análise
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