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1.
ACS Appl Mater Interfaces ; 12(45): 50344-50354, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33124794

RESUMO

High-entropy oxides based on transition metals, such as Mg0.2Co0.2Ni0.2Cu0.2Zn0.2O (TM-HEO), have recently drawn special attention as potential anodes in lithium-ion batteries due to high specific capacity and cycling reversibility. However, the lithiation/delithiation mechanism of such systems is still controversial and not clearly addressed. Here, we report on an operando XAS investigation into TM-HEO-based anodes for lithium-ion cells during the first lithiation/delithiation cycle. This material showed a high specific capacity exceeding 600 mAh g-1 at 0.1 C and Coulombic efficiency very close to unity. The combination of functional and advanced spectroscopic studies revealed complex charging mechanisms, developing through the reduction of transition-metal (TM) cations, which triggers the conversion reaction below 1.0 V. The conversion is irreversible and incomplete, leading to the final collapse of the HEO rock-salt structure. Other redox processes are therefore discussed and called to account for the observed cycling behavior of the TM-HEO-based anode. Despite the irreversible phenomena, the HEO cubic structure remains intact for ∼60% of lithiation capacity, so proving the beneficial role of the configuration entropy in enhancing the stability of the HEO rock-salt structure during the redox phenomena.

2.
Mar Pollut Bull ; 155: 111129, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32469765

RESUMO

Ten global harbours were assessed for sediment quality by quantifying the magnitude of anthropogenic change and ecological risk. Anthropogenic change (enrichment) was high for Derwent River and Sydney estuary, moderate for Santander Harbour, Rio de Janeiro and Dublin Port, slight for Hong Kong, minimal for Darwin. All 10 enrichment indices used showed similar results. Derwent River sediment was rated at high ecological risk, followed by Sydney and Santander estuaries with moderate risk. Auckland and Darwin sediments exhibited minimal ecological risk and sediment in the remaining harbours (Dublin, Hong Kong, Ravenna, Ria de Vigo and Rio de Janeiro) were assessed at slight ecological risk. The extraordinary variety of environments and types/quantities/qualities of data investigated resulted in as much a critique and development of methodology, as an assessment of human impact, including unique techniques for elemental normalisation and contaminant classification. Recommendations for an improved technical framework for sediment quality assessment are provided.


Assuntos
Metais Pesados/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Hong Kong , Humanos , Medição de Risco , Rios
3.
Sci Total Environ ; 658: 1293-1305, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30677991

RESUMO

Marine harbours are the focus of a diverse range of activities and subject to multiple anthropogenically induced pressures. Support for environmental management options aimed at improving degraded harbours depends on understanding the factors which influence people's perceptions of harbour environments. We used an online survey, across 12 harbours, to assess sources of variation people's perceptions of harbour health and ecological engineering. We tested the hypotheses: 1) people living near impacted harbours would consider their environment to be more unhealthy and degraded, be more concerned about the environment and supportive of and willing to pay for ecological engineering relative to those living by less impacted harbours, and 2) people with greater connectedness to the harbour would be more concerned about and have greater perceived knowledge of the environment, and be more supportive of, knowledgeable about and willing to pay for ecological engineering, than those with less connectedness. Across twelve locations, the levels of degradation and modification by artificial structures were lower and the concern and knowledge about the environment and ecological engineering were greater in the six Australasian and American than the six European and Asian harbours surveyed. We found that people's perception of harbours as healthy or degraded, but not their concern for the environment, reflected the degree to which harbours were impacted. There was a positive relationship between the percentage of shoreline modified and the extent of support for and people's willingness to pay indirect costs for ecological engineering. At the individual level, measures of connectedness to the harbour environment were good predictors of concern for and perceived knowledge about the environment but not support for and perceived knowledge about ecological engineering. To make informed decisions, it is important that people are empowered with sufficient knowledge of the environmental issues facing their harbour and ecological engineering options.

4.
Mar Pollut Bull ; 129(2): 762-771, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29108739

RESUMO

We analyzed the occurrence and status of infralittoral fringe populations of Cystoseira spp. (Fucales) at thirteen rocky sites around the Italian coastline, and explored the relationships with relevant environmental and anthropogenic variables. We found Cystoseira populations at 11 sites: most were scattered and comprised monospecific stands of C. compressa, and only 6 sites also supported sparse specimens of either C. amentacea var. stricta or C. brachycarpa. Coastal human population density, Chlorophyll a seawater concentrations, sea surface temperature, annual range of sea surface temperature and wave fetch explained most of the variation of the status of C. compressa. We hypothesize a generally unhealthy state of the Italian Cystoseira infralittoral fringe populations and identify multiple co-occurring anthropogenic stressors as the likely drivers of these poor conditions. Extensive baseline monitoring is needed to describe how Cystoseira populations are changing, and implement a management framework for the conservation of these valuable but vulnerable habitats.


Assuntos
Monitoramento Ambiental/métodos , Phaeophyceae/crescimento & desenvolvimento , Água do Mar/química , Clorofila/análise , Clorofila A , Ecossistema , Atividades Humanas , Humanos , Itália , Mar Mediterrâneo , Densidade Demográfica , Temperatura , Urbanização
5.
Mar Environ Res ; 131: 32-42, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28941644

RESUMO

We investigated how lateral erosion control, measured by novel photogrammetry techniques, is modified by the presence of Spartina spp. vegetation, sediment grain size, and the nutrient status of salt marshes across 230 km of the Italian Northern Adriatic coastline. Spartina spp. vegetation reduced erosion across our study sites. The effect was more pronounced in sandy soils, where erosion was reduced by 80% compared to 17% in silty soils. Erosion resistance was also enhanced by Spartina spp. root biomass. In the absence of vegetation, erosion resistance was enhanced by silt content, with mean erosion 72% lower in silty vs. sandy soils. We found no relevant relationships with nutrient status, likely due to overall high nutrient concentrations and low C:N ratios across all sites. Our results contribute to quantifying coastal protection ecosystem services provided by salt marshes in both sandy and silty sediments.


Assuntos
Monitoramento Ambiental , Fenômenos Geológicos , Áreas Alagadas , Organismos Aquáticos , Sedimentos Geológicos/química , Oceanos e Mares , Plantas
6.
J Environ Manage ; 189: 109-114, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28024197

RESUMO

Urbanisation in terrestrial systems has driven architects, planners, ecologists and engineers to collaborate on the design and creation of more sustainable structures. Examples include the development of 'green infrastructure' and the introduction of wildlife corridors that mitigate urban stressors and provide positive ecological outcomes. In contrast, efforts to minimise the impacts of urban developments in marine environments have been far more restricted in their extent and scope, and have often overlooked the ecological role of the built environment as potential habitat. Urban foreshore developments, i.e. those built on the interface of intertidal and/or subtidal zones, have the potential to incorporate clear multi-functional outcomes, by supporting novel ecosystems. We present a step-by-step eco-engineering framework for 'building blue' that will allow coastal managers to facilitate planning and construction of sustainable foreshore developments. Adopting such an approach will incorporate ecological principles, thereby mitigating some of the environmental impacts, creating more resilient urban infrastructure and environments, and maximising benefits to the multiple stakeholders and users of marine urban waterfronts.


Assuntos
Conservação dos Recursos Naturais , Urbanização , Ecologia/métodos , Ecossistema , Engenharia , Meio Ambiente , Oceanos e Mares
7.
Epigenetics ; 4(4): 221-30, 2009 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-19458486

RESUMO

Cell-free circulating DNA isolated from the plasma of individuals with cancer has been shown to harbor cancer-associated changes in DNA methylation, and thus it represents an attractive target for biomarker discovery. However, the reliable detection of DNA methylation changes in body fluids has proven to be technically challenging. Here we describe a novel combination of methods that allows quantitative and sensitive detection of DNA methylation in minute amounts of DNA present in body fluids (quantitative Methylation Analysis of Minute DNA amounts after whole Bisulfitome Amplification, qMAMBA). This method involves genome-wide amplification of bisulphite-modified DNA template followed by quantitative methylation detection using pyrosequencing and allows analysis of multiple genes from a small amount of starting DNA. To validate our method we used qMAMBA assays for four genes and LINE1 repetitive sequences combined with plasma DNA samples as a model system. qMAMBA offered high efficacy in the analysis of methylation levels and patterns in plasma samples with extremely small amounts of DNA and low concentrations of methylated alleles. Therefore, qMAMBA will facilitate methylation studies aiming to discover epigenetic biomarkers, and should prove particularly valuable in profiling a large sample series of body fluids from molecular epidemiology studies as well as in tracking disease in early diagnostics.


Assuntos
Metilação de DNA , Técnicas de Amplificação de Ácido Nucleico , Proteínas Adaptadoras de Transdução de Sinal/genética , Líquidos Corporais/citologia , Ilhas de CpG/genética , Genes p16 , Genoma Humano , Humanos , Elementos Nucleotídeos Longos e Dispersos/genética , Neoplasias Pulmonares/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Proteína 1 Homóloga a MutL , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Proteínas Supressoras de Tumor/genética
8.
Mar Pollut Bull ; 54(8): 1197-206, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17553532

RESUMO

Beach nourishment (i.e. the addition of sediments transported from other source locations) is increasingly used to counteract erosion of coastal areas. We tested whether sediment descriptors (grain size structure and organic content) and macrobenthic assemblages (species composition and abundance) differed among replicated shores previously exposed to nourishment alone (N), nourishment in combination with pre-existing hard structures (N+H) or no nourishment (NoN) along about 50 km of shores of the Emilia Romagna region (North Adriatic Sea, Italy). There was large variation among shores. Two out of three N shores were nearly defaunated, while one N shore had species composition and abundances comparable to NoN shores. There were also large differences between N and N+H shores, the latter possessing higher abundances of organisms and the presence of species that do not usually occur in the nearshore surf habitats in this region. More than 50% of the variability in the benthic assemblages was related to variations in the grain size structure of the sediments among shores. The results suggest that beach nourishments may lead to modifications of sedimentary environments and inhabiting fauna, but the resulting effects may be strongly related to local conditions, which dictate the rate at which added sand is redistributed.


Assuntos
Praias , Biodiversidade , Ecossistema , Sedimentos Geológicos/química , Invertebrados/fisiologia , Animais , Itália , Oceanos e Mares , Tamanho da Partícula , Densidade Demográfica , Análise de Regressão
9.
Ann Oncol ; 18(7): 1230-42, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17496311

RESUMO

BACKGROUND: We chose a set of candidate single nucleotide polymorphisms (SNPs) to investigate gene-environment interactions in three types of cancer that have been related to air pollution (lung, bladder and myeloid leukemia). PATIENTS AND METHODS: The study has been conducted as a nested case-control study within the European Prospective Investigation into Cancer and Nutrition cohort (409 cancer cases and 757 matched controls). We included never and ex-smokers. SNPs were in genes involved in oxidative stress, phase I metabolizing genes, phase II metabolizing genes and methylenetetrahydrofolate reductase (MTHFR). RESULTS: The most notable findings are: GSTM1 deletion and bladder cancer risk [odds ratio (OR) = 1.60; 95% confidence interval 1.00-2.56]; CYP1A1 and leukemia (2.22, 1.33-3.70; heterozygotes); CYP1B1 and leukemia (0.47, 0.27-0.84; homozygotes); MnSOD and leukemia (1.91, 1.08-3.38; homozygotes) and NQO1 and lung cancer (8.03, 1.73-37.3; homozygotes). Other statistically significant associations were found in subgroups defined by smoking habits (never or ex-smokers), environmental tobacco smoke or gender, with no obvious pattern. When gene variants were organized according to the three main pathways, the emerging picture was of a strong involvement of combined phase I enzymes in leukemia, with an OR of 5 (1.63-15.4) for those having three or more variant alleles. The association was considerably stronger for leukemias arising before the age of 55.


Assuntos
Predisposição Genética para Doença , Leucemia Mieloide/genética , Neoplasias Pulmonares/genética , Redes e Vias Metabólicas/genética , Neoplasias da Bexiga Urinária/genética , Hidrocarboneto de Aril Hidroxilases/genética , Arilamina N-Acetiltransferase/genética , Estudos de Casos e Controles , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1B1 , Feminino , Glutationa Transferase/genética , Humanos , Isoenzimas/genética , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Pessoa de Meia-Idade , Estresse Oxidativo/genética , Polimorfismo de Nucleotídeo Único , Fumar , Sulfotransferases/genética
10.
Carcinogenesis ; 28(2): 414-22, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16956909

RESUMO

It is becoming increasingly evident that single-locus effects cannot explain complex multifactorial human diseases like cancer. We applied the multi-factor dimensionality reduction (MDR) method to a large cohort study on gene-environment and gene-gene interactions. The study (case-control nested in the EPIC cohort) was established to investigate molecular changes and genetic susceptibility in relation to air pollution and environmental tobacco smoke (ETS) in non-smokers. We have analyzed 757 controls and 409 cases with bladder cancer (n=124), lung cancer (n=116) and myeloid leukemia (n=169). Thirty-six gene variants (DNA repair and metabolic genes) and three environmental exposure variables (measures of air pollution and ETS at home and at work) were analyzed. Interactions were assessed by prediction error percentage and cross-validation consistency (CVC) frequency. For lung cancer, the best model was given by a significant gene-environment association between the base excision repair (BER) XRCC1-Arg399Gln polymorphism, the double-strand break repair (DSBR) BRCA2-Asn372His polymorphism and the exposure variable 'distance from heavy traffic road', an indirect and robust indicator of air pollution (mean prediction error of 26%, P<0.001, mean CVC of 6.60, P=0.02). For bladder cancer, we found a significant 4-loci association between the BER APE1-Asp148Glu polymorphism, the DSBR RAD52-3'-untranslated region (3'-UTR) polymorphism and the metabolic gene polymorphisms COMT-Val158Met and MTHFR-677C>T (mean prediction error of 22%, P<0.001, mean CVC consistency of 7.40, P<0.037). For leukemia, a 3-loci model including RAD52-2259C>T, MnSOD-Ala9Val and CYP1A1-Ile462Val had a minimum prediction error of 31% (P<0.001) and a maximum CVC of 4.40 (P=0.086). The MDR method seems promising, because it provides a limited number of statistically stable interactions; however, the biological interpretation remains to be understood.


Assuntos
Neoplasias/genética , Resistência a Múltiplos Medicamentos , Humanos , Polimorfismo de Nucleotídeo Único , Probabilidade , Estudos Prospectivos
11.
Carcinogenesis ; 27(5): 997-1007, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16308313

RESUMO

Environmental carcinogens contained in air pollution, such as polycyclic aromatic hydrocarbons, aromatic amines or N-nitroso compounds, predominantly form DNA adducts but can also generate interstrand cross-links and reactive oxygen species. If unrepaired, such lesions increase the risk of somatic mutations and cancer. Our study investigated the relationships between 22 polymorphisms (and their haplotypes) in 16 DNA repair genes belonging to different repair pathways in 1094 controls and 567 cancer cases (bladder cancer, 131; lung cancer, 134; oral-pharyngeal cancer, 41; laryngeal cancer, 47; leukaemia, 179; death from emphysema and chronic obstructive pulmonary disease, 84). The design was a case-control study nested within a prospective investigation. Among the many comparisons, few polymorphisms were associated with the diseases at the univariate analysis: XRCC1-399 Gln/Gln variant homozygotes [odds ratios (OR) = 2.20, 95% confidence intervals (CI) = 1.16-4.17] and XRCC3-241 Met/Met homozygotes (OR = 0.51, 95% CI = 0.27-0.96) and leukaemia. The recessive model in the stepwise multivariate analysis revealed a possible protective effect of XRCC1-399Gln/Gln in lung cancer (OR = 0.22, 95% CI = 0.05-0.98), and confirmed an opposite effect (OR = 2.47, 95% CI = 1.02-6.02) in the leukaemia group. Our results also suggest that the XPD/ERCC1-GAT haplotype may modulate leukaemia (OR = 1.28, 95% CI = 1.02-1.61), bladder cancer (OR = 1.38, 95% CI = 1.06-1.79) and possibly other cancer risks. Further investigations of the combined effects of polymorphisms within these DNA repair genes, smoking and other risk factors may help to clarify the influence of genetic variation in the carcinogenic process.


Assuntos
Reparo do DNA , Neoplasias/genética , Neoplasias/patologia , Polimorfismo Genético , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Estudos Prospectivos , Risco , Fumar
12.
Mutat Res ; 574(1-2): 92-104, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15991349

RESUMO

Several large prospective investigations are under way or are planned in different parts of the world, aiming at the investigation of gene-environment interactions for chronic diseases. Technical, practical and ethical issues are raised by such large investigations. Here we describe how such issues were approached within a case-control study nested in EPIC, a large European cohort, and the kind of validation studies that have been set up. The GenAir investigation aimed at measuring the effects of air pollution and environmental tobacco smoke on human health in EPIC with a nested design and with biological measures. Validation studies included (a) comparisons between cotinine measurements, hemoglobin adducts and questionnaire data; (b) an analysis of the determinants of DNA adduct concentration; (c) comparison among different genotyping methods; (d) an analysis of the determinants of plasma DNA amounts. We also describe how the ethical issues were dealt with in our investigation.


Assuntos
Poluição do Ar/efeitos adversos , Biomarcadores/análise , Técnicas de Laboratório Clínico , Poluição por Fumaça de Tabaco/efeitos adversos , Estudos de Casos e Controles , Estudos de Coortes , Cotinina/análise , DNA , Adutos de DNA , Genótipo , Hemoglobinas/análise , Humanos , Mutação , Estudos Prospectivos , Reprodutibilidade dos Testes
13.
BMJ ; 330(7486): 277, 2005 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-15681570

RESUMO

OBJECTIVES: To investigate the association between environmental tobacco smoke, plasma cotinine concentration, and respiratory cancer or death. DESIGN: Nested case-control study within the European prospective investigation into cancer and nutrition (EPIC). PARTICIPANTS: 303,020 people from the EPIC cohort (total 500,000) who had never smoked or who had stopped smoking for at least 10 years, 123,479 of whom provided information on exposure to environmental tobacco smoke. Cases were people who developed respiratory cancers or died from respiratory conditions. Controls were matched for sex, age (plus or minus 5 years), smoking status, country of recruitment, and time elapsed since recruitment. MAIN OUTCOME MEASURES: Newly diagnosed cancer of lung, pharynx, and larynx; deaths from chronic obstructive pulmonary disease or emphysema. Plasma cotinine concentration was measured in 1574 people. RESULTS: Over seven years of follow up, 97 people had newly diagnosed lung cancer, 20 had upper respiratory cancers (pharynx, larynx), and 14 died from chronic obstructive pulmonary disease or emphysema. In the whole cohort exposure to environmental tobacco smoke was associated with increased risks (hazard ratio 1.30, 95% confidence interval 0.87 to 1.95, for all respiratory diseases; 1.34, 0.85 to 2.13, for lung cancer alone). Higher results were found in the nested case-control study (odds ratio 1.70, 1.02 to 2.82, for respiratory diseases; 1.76, 0.96 to 3.23, for lung cancer alone). Odds ratios were consistently higher in former smokers than in those who had never smoked; the association was limited to exposure related to work. Cotinine concentration was clearly associated with self reported exposure (3.30, 2.07 to 5.23, for detectable/non-detectable cotinine), but it was not associated with the risk of respiratory diseases or lung cancer. Frequent exposure to environmental tobacco smoke during childhood was associated with lung cancer in adulthood (hazard ratio 3.63, 1.19 to 11.11, for daily exposure for many hours). CONCLUSIONS: This large prospective study, in which the smoking status was supported by cotinine measurements, confirms that environmental tobacco smoke is a risk factor for lung cancer and other respiratory diseases, particularly in ex-smokers.


Assuntos
Neoplasias Laríngeas/etiologia , Neoplasias Pulmonares/etiologia , Neoplasias Faríngeas/etiologia , Doença Pulmonar Obstrutiva Crônica/etiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto , Idoso , Biomarcadores/sangue , Cotinina/sangue , Métodos Epidemiológicos , Feminino , Humanos , Neoplasias Laríngeas/sangue , Neoplasias Laríngeas/mortalidade , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasias Faríngeas/sangue , Neoplasias Faríngeas/mortalidade , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/mortalidade , Fumar/efeitos adversos , Fumar/sangue
15.
Br J Cancer ; 87(11): 1230-3, 2002 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-12439711

RESUMO

The role of fried foods on laryngeal cancer risk was investigated in a case-control study from Italy and Switzerland on 527 cases and 1,297 hospital controls. A significant increased risk was found for high consumption of fried meat, fish, eggs and potatoes, with odds ratios of 1.6, 3.1, 1.9 and 1.9, respectively.


Assuntos
Culinária , Gorduras na Dieta , Neoplasias Laríngeas/etiologia , Adulto , Idoso , Animais , Dieta , Ovos , Feminino , Peixes , Humanos , Itália/epidemiologia , Neoplasias Laríngeas/epidemiologia , Masculino , Carne , Pessoa de Meia-Idade , Razão de Chances , Medição de Risco , Solanum tuberosum , Suíça/epidemiologia
16.
Nutr Cancer ; 39(1): 42-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11588901

RESUMO

Several N-nitroso compounds, present in foods and beverages or formed in the stomach from their precursors, act as alkylating agents. By using a highly reliable technique (high-resolution gas chromatography-mass spectrometry with negative-ion chemical ionization and selected ion recording), we measured a series of specific O6-alkylguanines in snap-frozen paired stomach tissue samples (tumor and noninvolved mucosa) obtained at surgery from 24 gastric cancer patients identified in Florence, Italy. Samples of noninvolved mucosa had higher levels of total O6-alkylguanines and more frequently detectable levels (54%) than tumor samples (29.2%). O6-propylguanine and O6-methylguanine were the single adducts most frequently detected in noninvolved mucosa and tumor tissue, respectively. Tumor samples showed higher levels of total O6-alkylguanines in female patients (p = 0.03) and among those with a diffuse histological type (p = 0.06) or seronegative for Helicobacter pylori CagA antibodies (p = 0.06). Mean dietary nitrate intake was significantly higher in patients with detectable levels of adducts in tumor samples (p = 0.03). Estimated intakes of dimethylamine and N-nitrosodimethylamine correlated with total levels of O6-alkylguanines in noninvolved gastric mucosa. These findings, although based on a small series of cases, support a role for N-nitroso compounds from dietary sources in the etiology of gastric cancer.


Assuntos
Adutos de DNA/análise , Mucosa Gástrica/química , Guanina/análise , Compostos Nitrosos/análise , Neoplasias Gástricas/química , Idoso , Anticorpos Antibacterianos/sangue , Dieta , Dimetilaminas/análise , Dimetilnitrosamina/análise , Feminino , Análise de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Suco Gástrico/química , Mucosa Gástrica/patologia , Helicobacter pylori/imunologia , Helicobacter pylori/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Nitrosos/efeitos adversos , Neoplasias Gástricas/etiologia , Inquéritos e Questionários
17.
Alcohol Clin Exp Res ; 25(2): 221-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11236836

RESUMO

BACKGROUND: Although multiple genes are involved in alcoholism and can contribute differently to the risk of dependence and liver damage, no studies have investigated susceptibility to addiction in combination with susceptibility to liver damage due to differences in ethanol metabolism. METHODS: We evaluated the role of three polymorphic genes related to alcohol metabolism (CYP2E1) and, possibly, dependence (DRD2 and SLC6A4 promoter) in a series of 60 alcoholics admitted to a specialized referral center in Florence, Italy. Eighteen had a diagnosis of liver cirrhosis. A control series of 64 blood donors were identified at the same hospital. Genotyping was done by polymerase chain reaction-restriction fragment length polymorphism methods. RESULTS: No difference was found in the frequency of the CYP2E1 Rsal c2 allele (2.5% among alcoholics and 4.7% among controls) and the DraI C allele (6.7% and 10.1%). Similarly, no difference was found in the frequency of the DRD2 A1 allele (15.8% and 13.3%) and the B1 allele (10.8% and 8.6%). The proportion of controls with a combined B1 genotype (B1/B1 or B1/B2) was significantly associated with smoking (p = 0.03). The distribution of the S and L allele of the SLC6A4 gene was similar in the two groups, with 15% and 14%, respectively, homozygous S/S carriers. A significant association, however, emerged in the group of alcoholics, with a five times higher risk for S/S carriers of developing cirrhosis (p < 0.05). This association with liver persisted even after exclusion of the subgrouped of 10 hepatitis C virus positive alcoholics. CONCLUSIONS: Overall, our results provided no evidence of an increased susceptibility to develop alcoholism that was associated with the three genotypes investigated, either alone or in combination. An increased risk of developing liver cirrhosis for S/S homozygous carriers among alcohol-dependent patients was observed for the first time.


Assuntos
Alcoolismo/genética , Etanol/metabolismo , Proteínas de Membrana Transportadoras , Proteínas do Tecido Nervoso , Adulto , Alcoolismo/virologia , Proteínas de Transporte/genética , Citocromo P-450 CYP2E1/genética , Feminino , Predisposição Genética para Doença , Genótipo , Hepatite C/complicações , Humanos , Itália , Cirrose Hepática Alcoólica/genética , Cirrose Hepática Alcoólica/virologia , Masculino , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Regiões Promotoras Genéticas , Receptores de Dopamina D2/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina , Fumar/genética
18.
Biomarkers ; 6(5): 357-74, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-23889309

RESUMO

We investigated whether the presence of (+)-anti-benzo(a)pyrene diolepoxide adducts to serum albumin (BPDE-SA) among workers exposed to benzo(a)pyrene (BaP) and unexposed reference controls was influenced by genetic polymorphisms of cytochrome P4501A1 (CYP1A1), microsomal epoxide hydrolase (EHPX), glutathione S-transferases M1 (GSTM1) and P1 (GSTP1), all involved in BaP metabolism. Exposed workers had significantly higher levels of adducts (0.124 ± 0.02 fmol BPTmg(-1) SA, mean ± SE) and a higher proportion of detectable adducts (40.3%) than controls (0.051 ± 0.01 fmol BPT mg(-1) SA; 16.1%) (p = 0:014 and p = 0:012). Smoking increased adduct levels only in occupationally exposed workers with the GSTM1 deletion (GSTM1 null) (p = 0:034). Smokers from the exposed group had higher adduct levels when they were CYP1A1 *1/*1 wild-type rather than heterozygous and homozygous for the variant alleles (CYP1A1 *1/*2 plus *2/*2) (p = 0:01). The dependence of BPDE-SA adduct levels and frequency on the CYP1A1 *1/*1 genotype was most pronounced in GSTM1-deficient smokers. Exposed workers with GSTM1 null/GSTP1 variant alleles had fewer detectable adducts than those with the GSTM1 null/GSTP1*A wild-type allele, supporting for the first time the recent in vitro finding that GSTP1 variants may be more effective in the detoxification of BPDE than the wild-type allele. Logistic regression analysis indicated that occupational exposure, wild-type CYP1A1*1/*1 allele and the combination of GSTM1 null genotype+EHPX genotypes associated with predicted low enzyme activity were significant predictors of BPDE-SA adducts. Though our findings should be viewed with caution because of the relatively limited size of the population analysed, the interaction between these polymorphic enzymes and BPDE-SA adducts seems to be specific for high exposure and might have an impact on the quantitative risk estimates for exposure to polycyclic aromatic hydrocarbons.

20.
Int J Cancer ; 88(1): 1-6, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10962432

RESUMO

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is the most abundant heterocyclic amine formed in meat and fish during cooking and can be used as a model compound for this class of chemicals possibly involved in human carcinogenesis. Knowing the exposure to heterocyclic amines is important for establishing their role in human diseases. Serum albumin (SA) and globin (Gb) adducts were first tested as biomarkers of exposure to PhIP in male Fischer 344 rats given oral doses of 0.1, 0.5, 1 and 10 mg/kg. Blood samples were collected 24 hr after treatment and PhIP released from SA and Gb after acidic hydrolysis was analyzed by gas chromatography-mass spectrometry or liquid chromatography-tandem mass spectrometry. PhIP-SA and Gb adducts increased linearly with the dose. Studies on 35 volunteers with different dietary habits exhibited that diet was a major determinant in the formation of both adducts. PhIP-SA adducts were significantly higher in meat consumers than in vegetarians (6.7 +/- 1.6 and 0.7 +/- 0.3 fmol/mg SA; respectively, mean +/- SE; p = 0.04, Mann-Whitney U test). The Gb adduct pattern was quantitatively lower but paralleled SA (3 +/- 0.8 in meat consumers and 0.3 +/- 0.1 in vegetarians). PhIP-SA adducts were no different in smokers and in non-smokers. The results show for the first time that PhIP-blood protein adducts are present in humans not given the synthetic compound. Both biomarkers appear to be suitable for assessing dietary exposure and internal PhIP dose and may be promising tools for studying the role of heterocyclic amines in the etiology of colon cancer and other diseases.


Assuntos
Carcinógenos/metabolismo , Dieta , Hemoglobinas/metabolismo , Imidazóis/sangue , Albumina Sérica/metabolismo , Animais , Biomarcadores/sangue , Cromatografia Líquida , Dieta Vegetariana , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidrólise , Masculino , Espectrometria de Massas , Carne , Ligação Proteica , Ratos , Ratos Endogâmicos F344 , Sensibilidade e Especificidade
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