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1.
Tumori ; 105(5): 404-410, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30915902

RESUMO

PURPOSE: To assess whether asbestos fibers may be observed in liver tissue of patients with cholangiocarcinoma (CC) with environmental or working asbestos exposure. METHODS: Detection of fibers was performed directly on histologic sections of liver from 7 patients with CC using optical microscope and variable pressure scanning electron microscopy equipped with energy-dispersive spectroscopy (VP-SEM/EDS). All patients were from Casale Monferrato, Italy, a highly asbestos-polluted town. Due to ethical constraints, observers were blinded to patients' clinical features. RESULTS: Fibers/bundles of fibers of chrysotile were detected in 5 out of 7 patients (71%). The boundary between healthy and neoplastic tissue or the fibrocollagen tissue produced by the neoplasia were identified as areas of fiber incorporation. CONCLUSIONS: This study is the first report about the detection of chrysotile asbestos fibers in the liver of patients with CC. Further studies on larger cohorts are needed to corroborate our preliminary findings.


Assuntos
Amianto/toxicidade , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Fígado/diagnóstico por imagem , Amianto/isolamento & purificação , Neoplasias dos Ductos Biliares/induzido quimicamente , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/induzido quimicamente , Colangiocarcinoma/patologia , Poluentes Ambientais/isolamento & purificação , Poluentes Ambientais/toxicidade , Feminino , Humanos , Itália , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Mesotelioma/induzido quimicamente , Microscopia Eletrônica de Varredura , Exposição Ocupacional
2.
Micron ; 105: 98-104, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29248759

RESUMO

The methods conventionally used to determine the burden of asbestos fibres inhaled/incorporated in lung require chemical digestion of the biological matrix before counting/characterising the inorganic fibrous phases under scanning electron microscopy and energy dispersive spectroscopy (SEM/EDS). Asbestos fibres can also be present in extra-pulmonary organs, and we set out to quantify the fibres in gallbladder. Although the standardised procedure requires approximately 5 × 10-1 g of wet tissue, this amount of tissue is not always available. We applied the procedure on about 9 × 10-4 g of gallbladder from a patient with known environmental and workplace exposure to asbestos. The patient died of malignant pleural mesothelioma and was also affected by severe bile-tract problems. The traditional procedure of digesting tissue samples in NaClO and filtering the resulting suspension was carried out. The filter was then examined under SEM/EDS using two methods 1. following the standardised procedure to assess the fibre burden in lung by investigating only 2 mm2 of the filter (660 microscopic fields), and 2. analysing all the microscopic fields in one-quarter of the filter (about 82 mm2). In parallel, histological sections (prepared in the usual way for medical diagnosis) were analysed without digestion or manipulation of the sample using variable pressure SEM/EDS. The fibre counts obtained using the two methods were of the same order of magnitude, i.e., ∼105 fibres/g of wet tissue. We showed that the counting of fibres in human tissue may be successfully carried out even when a limited amount of tissue is available. We also found that, when exposure to asbestos is considerable, the number of asbestos fibres accumulating in the gallbladder may be significant.


Assuntos
Asbesto Crocidolita/toxicidade , Asbestos Serpentinas/toxicidade , Vesícula Biliar/química , Neoplasias Pulmonares/mortalidade , Mesotelioma/mortalidade , Exposição Ocupacional/efeitos adversos , Idoso de 80 Anos ou mais , Asbesto Crocidolita/isolamento & purificação , Asbestos Serpentinas/isolamento & purificação , Feminino , Vesícula Biliar/patologia , Humanos , Neoplasias Pulmonares/patologia , Mesotelioma/patologia , Mesotelioma Maligno
3.
Inhal Toxicol ; 28(8): 357-63, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27151190

RESUMO

The purpose of this work is to define a sample preparation protocol that allows inorganic fibers and particulate matter extracted from different biological samples to be characterized morphologically, crystallographically and chemically by transmission electron microscopy-energy dispersive spectroscopy (TEM-EDS). The method does not damage or create artifacts through chemical attacks of the target material. A fairly rapid specimen preparation is applied with the aim of performing as few steps as possible to transfer the withdrawn inorganic matter onto the TEM grid. The biological sample is previously digested chemically by NaClO. The salt is then removed through a series of centrifugation and rinse cycles in deionized water, thus drastically reducing the digestive power of the NaClO and concentrating the fibers for TEM analysis. The concept of equivalent hydrodynamic diameter is introduced to calculate the settling velocity during the centrifugation cycles. This technique is applicable to lung tissues and can be extended to a wide range of organic materials. The procedure does not appear to cause morphological damage to the fibers or modify their chemistry or degree of crystallinity. The extrapolated data can be used in interdisciplinary studies to understand the pathological effects caused by inorganic materials.


Assuntos
Amiantos Anfibólicos/análise , Asbestos Serpentinas/análise , Manejo de Espécimes/métodos , Amiantos Anfibólicos/química , Asbestos Serpentinas/química , Humanos , Pulmão , Microscopia Eletrônica de Transmissão , Hipoclorito de Sódio/química
4.
Microsc Microanal ; 21(5): 1341-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26286705

RESUMO

Erionite samples from Rome, Oregon (USA) and Karlik, Cappadocia (Turkey) were analyzed by environmental scanning electron microscopy (E-SEM) coupled with energy-dispersive spectroscopy (EDS) to verify the chemical composition of this mineral phase, and the presence of iron in particular. By means of backscattered electron images, a large number of particles/grains were observed on the surface of the erionite fibers from both locations. The particles were found to be micrometric on samples from Rome and submicrometric on samples from Karlik, and always lighter than the hosting crystal in appearance. In different areas of the same fiber or bundle of fibers, several EDS spectra were recorded. Iron was detected only when a light particle was lying in the path of the electron beam. Iron was never identified in the EDS spectra acquired on the flat erionite surface. The results from E-SEM/EDS were confirmed by micro-Raman spectroscopy, showing bands ascribing to hematite­Fe2O3, goethite­FeO(OH), or jarosite­KFe3(3+)(SO4)2(OH)6 when the laser beam was addressed on the light particles observed on the fiber surface. The evidence that iron is on the surface of erionite fibers, rather than being part of the crystalline structure, may be relevant for the carcinogenic potential of these fibers.


Assuntos
Ferro/análise , Material Particulado/química , Zeolitas/química , Carcinógenos/química , Microscopia Eletrônica de Varredura , Oregon , Espectrometria por Raios X , Análise Espectral Raman , Turquia
5.
Eur J Gastroenterol Hepatol ; 27(7): 860-4, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25856690

RESUMO

PURPOSE: This exploratory study aimed to evaluate the presence of asbestos fibers in the biliary tract of patients living in an asbestos-polluted area using scanning electron microscopy. METHODS: Thin gallbladder sections were obtained from five patients who were operated on for gallbladder stones and the bile fluid of one of the patients was analyzed using variable-pressure scanning electron microscopy coupled with energy-dispersive spectroscopy. All patients were from Casale Monferrato, Italy, a well-known asbestos-polluted city, where the Eternit factory had operated since the beginning of the century until 1985. RESULTS: All the inorganic phases found in the gallbladder were analyzed for morphology and chemistry. Fibers and particles consistent with minerals defined by law as 'asbestos' were detected in three out of five patients. CONCLUSION: These findings suggest that asbestos fibers can be found in the gallbladder of patients exposed to asbestos, although how they reach the biliary tract remains unknown. Further studies to confirm these results are under way.


Assuntos
Amianto/efeitos adversos , Doenças Biliares/etiologia , Doenças Biliares/patologia , Carcinógenos , Exposição Ambiental/efeitos adversos , Microscopia Eletrônica de Varredura , População Urbana , Adolescente , Adulto , Idoso , Asbesto Crocidolita/efeitos adversos , Asbestos Serpentinas/efeitos adversos , Doenças Biliares/cirurgia , Feminino , Vesícula Biliar/patologia , Humanos , Itália/epidemiologia , Microscopia Eletrônica de Varredura/métodos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Espectrometria por Raios X/métodos
6.
Am J Pathol ; 183(5): 1654-66, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24160326

RESUMO

Malignant mesothelioma is strongly associated with asbestos exposure. Among asbestos fibers, crocidolite is considered the most and chrysotile the least oncogenic. Chrysotile accounts for more than 90% of the asbestos used worldwide, but its capacity to induce malignant mesothelioma is still debated. We found that chrysotile and crocidolite exposures have similar effects on human mesothelial cells. Morphological and molecular alterations suggestive of epithelial-mesenchymal transition, such as E-cadherin down-regulation and ß-catenin phosphorylation followed by nuclear translocation, were induced by both chrysotile and crocidolite. Gene expression profiling revealed high-mobility group box-1 protein (HMGB1) as a key regulator of the transcriptional alterations induced by both types of asbestos. Crocidolite and chrysotile induced differential expression of 438 out of 28,869 genes interrogated by oligonucleotide microarrays. Out of these 438 genes, 57 were associated with inflammatory and immune response and cancer, and 14 were HMGB1 targeted genes. Crocidolite-induced gene alterations were sustained, whereas chrysotile-induced gene alterations returned to background levels within 5 weeks. Similarly, HMGB1 release in vivo progressively increased for 10 or more weeks after crocidolite exposure, but returned to background levels within 8 weeks after chrysotile exposure. Continuous administration of chrysotile was required for sustained high serum levels of HMGB1. These data support the hypothesis that differences in biopersistence influence the biological activities of these two asbestos fibers.


Assuntos
Asbestos Serpentinas/toxicidade , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Epitélio/patologia , Proteína HMGB1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Animais , Asbesto Crocidolita/toxicidade , Caderinas/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular , Forma Celular/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Genoma Humano/genética , Proteína HMGB1/sangue , Humanos , Camundongos , Transdução de Sinais/genética , Transcrição Gênica/efeitos dos fármacos , beta Catenina/metabolismo
7.
Environ Monit Assess ; 185(9): 7647-58, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23456221

RESUMO

The Bormida River Basin, located in the northwestern region of Italy, has been strongly contaminated by the ACNA chemical factory. This factory was in operation from 1892 to 1998, and contamination from the factory has had deleterious consequences on the water quality, agriculture, natural ecosystems and human health. Attempts have been made to remediate the site. The aims of this study were to use high-resolution satellite images combined with a classical remote sensing methodology to monitor vegetation conditions along the Bormida River, both upstream and downstream of the ACNA chemical factory site, and to compare the results obtained at different times before and after the remediation process. The trends of the Normalised Difference Vegetation Index (NDVI) and the Enhanced Vegetation Index (EVI) along the riverbanks are used to assess the effect of water pollution on vegetation. NDVI and EVI values show that the contamination produced by the ACNA factory had less severe effects in the year 2007, when most of the remediation activities were concluded, than in 2006 and 2003. In 2007, the contamination effects were noticeable up to 6 km downstream of the factory, whereas in 2003 and 2006 the influence range was up to about 12 km downstream of the factory. The results of this study show the effectiveness of remediation activities that have been taking place in this area. In addition, the comparison between NDVI and EVI shows that the EVI is more suitable to characterise the vegetation health and can be considered an additional tool to assess vegetation health and to monitor restoration activities.


Assuntos
Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos , Rios/química , Imagens de Satélites , Poluição da Água/análise , Agricultura , Itália , Poluição da Água/estatística & dados numéricos
8.
J Hazard Mater ; 248-249: 69-80, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23380447

RESUMO

In this work, the high-temperature inertization product of a representative batch of samples of cement-asbestos (CA) from different localities in Italy have been characterized with a multidisciplinary approach. All the raw CA samples were heated at 1200°C for 15 min. After firing, they underwent a series of solid state reactions leading to global structural changes of the matrix. Effects of annealing time and temperature on the crystallization kinetics were thoroughly investigated. Both factors acted in favour of equilibrium. Three classes of CA were identified with the aid of phase diagrams and of specific plots relating chemical and mineralogical parameters. This result was considered of importance in view of the potential use of transformed cement-asbestos as a secondary raw material. In principle, the content of CA packages removed from the environment and their corresponding heat-treated products can be classified simply using XRF. This method allows for the selection of appropriate fractions in function of the most suitable recycling solution adopted. Samples belonging to the class called larnite-rich, turned out to be of great interest as possible candidate for substituting a fraction of cement in many building materials and innovative green cement productions.


Assuntos
Amianto/química , Materiais de Construção , Gerenciamento de Resíduos/métodos , Cristalização , Temperatura Alta , Microscopia Eletrônica de Varredura , Difração de Pó , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Difração de Raios X
9.
Microsc Microanal ; 19(2): 420-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23442447

RESUMO

Ferruginous bodies observed in lungs of patients affected by mesothelioma, asbestosis, and pulmonary carcinoma are important to relate the illness to exposure, environmental or occupational, to asbestos. Identification of the inorganic phase constituting the core of the ferruginous bodies, formed around asbestos but also around phases different from asbestos, is essential for legal purposes. Environmental scanning electron microscopy/energy dispersive spectroscopy was used to identify the fibrous mineral phase in the core of ferruginous bodies observed directly in thin sections of tissue, without digestion of the biological matrix. Spectra were taken with sequential analyses along a line crossing the core of the ferruginous bodies. By comparing the spectra taken near to and far from the core, the chemical elements that make up the core could be identified.


Assuntos
Amianto/análise , Neoplasias Pulmonares/patologia , Pulmão/ultraestrutura , Mesotelioma/patologia , Microscopia Eletrônica de Varredura/métodos , Espectrometria por Raios X/métodos , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/toxicidade , Amianto/toxicidade , Humanos , Pulmão/química , Pulmão/patologia
10.
Environ Monit Assess ; 184(7): 4461-72, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21830066

RESUMO

A new index named Air Quality Balance Index (AQBI), which is able to characterise the amount of pollution level in a selected area, is proposed. This index is a function of the ratios between pollutant concentration values and their standards; it aims at identifying all situations in which there is a possible environmental risk even when several pollutants are below their limit values but air quality is reduced. AQBI is evaluated by using a high-resolution three-dimensional dispersion model: the air concentration for each substance is computed starting from detailed emissions sources: point, line and area emissions hourly modulated. This model is driven with accurate meteorological data from ground stations and remote sensing systems providing vertical profiles of temperature and wind; these data are integrated with wind and temperature profiles at higher altitudes obtained by a Local Area Model. The outputs of the dispersion model are compared with pollutant concentrations provided by measuring stations, in order to recalibrate emission data. A three-dimensional high resolution grid of AQBI data is evaluated for an industrial area close to Alessandria (Northern Italy), assessing air quality and environmental conditions. Performance of AQBI is compared with the Air Quality Index (AQI) developed by the U.S. Environmental Protection Agency. AQBI, computed taking into account all pollutants, is able to point out situations not evidenced by AQI, based on a preset limited number of substances; therefore, AQBI is a good tool for evaluating the air quality either in urban and in industrial areas. The AQBI values at ground level, in selected points, are in agreement with in situ observations.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Poluentes Atmosféricos/normas , Automóveis/estatística & dados numéricos , Humanos , Indústrias/estatística & dados numéricos , Itália , Modelos Químicos , Emissões de Veículos/análise
11.
Appl Spectrosc ; 64(6): 571-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20537223

RESUMO

In a previous work it has been demonstrated that micro-Raman spectroscopy is a technique able to recognize crystalline phases on untreated samples. In that case, inorganic particles and uncoated fibers from bronchoalveolar lavage (BAL) of a patient affected by pneumoconiosis were identified and characterized. In this work the technique is applied to asbestos bodies, that is, to coated fibers, and on crystallizations and fibrous phases observed in the plural plaque from patients affected by mesothelioma. From the Raman analysis the abundant fibrous material observed in the pleural area is talc, whereas rounded grains in the pleural tissue show the Raman spectrum of apatite, a calcium phosphate mineral particular to bones. In the pulmonary tissue many asbestos bodies, consisting of the incorporated fibers coated by iron-rich proteins, were observed. Under the 632.8 nm laser beam of the spectrometer, photo-crystallization of hematite in the iron-rich material forming the asbestos bodies can be proposed by the changes in the Raman spectra acquired during subsequent acquisitions. Nevertheless, the identification of the mineral phase constituting the incorporated fiber was possible by analyzing the Raman spectra; the results were confirmed by variable pressure scanning electron microscopy with annexed energy dispersive spectroscopy (VP-SEM-EDS) analyses.


Assuntos
Amianto/análise , Neoplasias Pulmonares/patologia , Pulmão/patologia , Mesotelioma/patologia , Microscopia Eletrônica de Varredura/métodos , Análise Espectral Raman/métodos , Humanos , Doenças Pleurais/patologia
12.
J Hazard Mater ; 167(1-3): 1070-9, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19264404

RESUMO

The chrysotile fibres toxicity appears correlated to the redox activity of iron present in the chrysotile structure. In fact the generation of reactive oxygen species and other radicals appears catalyzed by iron ions and closely related to Fe ions organization in specific crystallographic sites having a capability to activate free radical generation. The Fe substitution to Mg and/or Si in the chrysotile structure appears important for asbestos health hazard investigation. Infrared and Raman spectroscopic analyses have been utilized to investigate Mg and/or Si ions replacement by Fe ions in chrysotile structure as a function of the Fe doping extent. Geoinspired synthetic chrysotile at different Fe doping extents has been obtained as unique phase by hydrothermal reaction in the presence or not of metallic Fe in the synthetic environment. The results highlight that Fe can replace both Mg and Si, differently modifying the chrysotile structure as a function of the Fe doping extent and the Fe doping process. The contemporary iron substitution into the octahedral and tetrahedral sheets reveals an appreciable increase of the dehydroxylation temperature which occurs at higher temperature than for iron-free sample. The results highlight the role of Fe substitution in the asbestos structure influencing the health hazard of biological systems.


Assuntos
Asbestos Serpentinas/química , Amianto/química , Saúde Ambiental , Ferro/química , Amianto/toxicidade , Asbestos Serpentinas/toxicidade , Substâncias Perigosas , Magnésio , Silício , Análise Espectral
13.
Chemosphere ; 63(6): 950-5, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16297964

RESUMO

The feasibility of electrokinetic remediation of copper-contaminated soil was evaluated following eight days of electroreclamation. The results indicate that electrokinetic reclamation of Cu is totally ineffective in soil composed primarily of clay minerals and organic matter. The strong absorption of copper by this kind of soil, in our view mainly a result of retention by the clay component, makes it resistant to mobilization by the electrogenerated acidic front as well as by citrates (the competitors of natural chelating agents, i.e., humates). Such conditions, while adverse for the electroremediation process, may cause this kind of soil to act as a natural barrier to the leaching of copper ions.


Assuntos
Cobre/análise , Metalurgia , Eliminação de Resíduos/métodos , Poluentes do Solo/análise , Solo/análise , Zinco/análise , Absorção , Eletrodos , Estudos de Viabilidade , Cinética , Solo/normas
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