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1.
J Endocrinol Invest ; 44(12): 2635-2643, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33860907

RESUMO

PURPOSE: Malignancy prediction in indeterminate thyroid nodules is still challenging. We prospectively evaluated whether the combination of ultrasound (US) risk stratification and molecular testing improves the assessment of malignancy risk in Bethesda Category IV thyroid nodules. METHODS: Ninety-one consecutively diagnosed Bethesda Category IV thyroid nodules were prospectively evaluated before surgery by both ACR- and EU-TIRADS US risk-stratification systems and by a further US-guided fine-needle aspiration cytology (FNAC) for the following molecular testing: BRAFV600E, N-RAS codons 12/13, N-RAS codon 61, H-RAS codons 12/13, H-RAS codon 61, K-RAS codons 12/13, and K-RAS codon 61 point-mutations, as well as PAX8/PPARγ, RET/PC1, and RET/PTC 3 rearrangements. RESULTS: At histology, 37% of nodules were malignant. No significant association was found between malignancy and either EU- or ACR-TIRADS. In total, 58 somatic mutations were identified, including 3 BRAFV600E (5%), 5 N-RAS 12/13 (9%), 13 N-RAS 61 (22%), 7 H-RAS 12/13 (12%), 11 H-RAS 61 (19%), 6 K-RAS 12/13 (10%), 8 K-RAS 61 (14%) mutations and 2 RET/PTC1 (4%), 0 RET/PTC 3 (0%), 3 PAX8/PPARγ (5%) rearrangements. At least one somatic mutation was found in 28% and 44% of benign and malignant nodules, respectively, although malignancy was not statistically associated with the outcome of the mutational test. However, the combination of ACR-, but not EU-, TIRADS with the presence of at least one somatic mutation, was significantly associated with malignant histology (P = 0.03). CONCLUSION: US risk stratification and FNAC molecular testing may synergistically contribute to improve malignancy risk estimate of Bethesda category IV thyroid nodules.


Assuntos
Biópsia por Agulha Fina/métodos , Técnicas de Diagnóstico Molecular/métodos , Medição de Risco/métodos , Glândula Tireoide , Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide/diagnóstico , Ultrassonografia/métodos , Feminino , Genes ras/genética , Humanos , Biópsia Guiada por Imagem/métodos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/epidemiologia , Fatores de Transcrição/genética
2.
Cancer Treat Res Commun ; 26: 100276, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33338854

RESUMO

The prognosis of patients affected by malignant pleural mesothelioma (MPM) is presently poor and no therapeutic strategies have improved their survival yet. Introduction of miRNA mimics to restore their reduced or absent functionality in cancer cells is considered an important opportunity and a combination of miR's might be even more effective. In the present study, miR-16 and miR-34a were transfected, singularly and in combination, in MPM cell lines H2052 and H28, and their effects on cell proliferation and sensitivity to cisplatin are reported. Interestingly, the overexpression of both miRs, alone or combined, slows down the cell cycle progression, modulates the p53 and HMGB1 expression and increases the sensitivity of cells to cisplatin, producing a marked impairment of cell proliferation and strengthening the apoptotic effect of the drug. However, the co-overexpression of the two miRs results more effective only in the regulation of the cell cycle, but does not enhance the sensitivity of MPM cells to cisplatin. Consequently, although the potential of miR-16 and miR-34a is confirmed, we must conclude that their combination does not improve the response of MPM to chemotherapy.


Assuntos
Cisplatino/farmacologia , Mesotelioma Maligno/genética , MicroRNAs/metabolismo , Neoplasias Pleurais/genética , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Proteína HMGB1/genética , Humanos , Mesotelioma Maligno/tratamento farmacológico , Mesotelioma Maligno/patologia , MicroRNAs/genética , Neoplasias Pleurais/tratamento farmacológico , Neoplasias Pleurais/patologia , Transfecção , Proteína Supressora de Tumor p53/genética
3.
J Breath Res ; 9(2): 027101, 2015 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-25634546

RESUMO

Lung cancer is one of the most frequently diagnosed cancers worldwide and is still the leading cause of cancer-related deaths. There is a considerable interest in finding diagnostic methods in the disease's earliest stages. A complementary approach to imaging techniques could be provided by exhaled breath gas phase and exhaled breath condensate (EBC) analysis. The aim of this study was to quantify various biomarkers in the exhaled breath gas phase and EBC in suspected cases of non-small-cell lung cancer (NSCLC). The study involved 138 subjects with suspected lung cancer, 71 of whom had a subsequent diagnosis of NSCLC. The diagnostic power of a combination of hydrogen peroxide (H2O2)-EBC, and exhaled pentane, 2-methyl pentane, hexane, ethyl benzene, heptanal, trans-2-nonenal in distinguishing NSCLC and non-NSCLC subjects was poor-to-fair (area under the curve (AUC) = 0.68), similar to that of smoking history alone (expressed as pack-years, AUC = 0.70); a further improvement was observed when smoking history was combined with exhaled compounds (AUC = 0.80). The diagnostic power was increased in those patients with little or no past smoke exposure (AUC = 0.92) or where past smoke exposure was up to 30 pack-years (AUC = 0.85). Exhaled substances had a good accuracy in discriminating suspected cancerous cases only in those subjects with a modest smoking history (≤ 30 pack-years), but the inclusion of other exhaled biomarkers may increase the overall accuracy, regardless of tobacco smoke.


Assuntos
Testes Respiratórios/métodos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Expiração , Neoplasias Pulmonares/diagnóstico , Idoso , Aldeídos/análise , Área Sob a Curva , Biomarcadores/análise , Intervalos de Confiança , Estudos Transversais , Feminino , Humanos , Peróxido de Hidrogênio/análise , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Curva ROC
4.
G Ital Med Lav Ergon ; 33(3 Suppl): 49-52, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-23393799

RESUMO

The aim of the study was to evaluate biomarkers of exposure to gasoline in petrol station workers by a combined approach of environmental and biological monitoring. The personal exposure to benzene, toluene, ethylbenzene and xylene (BTEX) and the urinary levels of BTEX, methyl tert-butyl ether (U-MTBE), trans,trans-muconic (t,t-MA) and S-phenylmercapturic acids (S-PMA) and cotinine were determined by mass spectrometry coupled chromatographic techniques. U-MTBE levels were strictly influenced by occupational exposure to gasoline, whereas both U-B and S-PMA levels depended from smoking habits and occupational exposure.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos/análise , Éteres Metílicos/análise , Exposição Ocupacional/análise , Adulto , Feminino , Gasolina , Humanos , Masculino
5.
G Ital Med Lav Ergon ; 33(3 Suppl): 69-72, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-23393804

RESUMO

Si-CAE was measured in 16 composite marble industry workers furthermore, a spirometry was performed and 8oxoGua, 8oxoGuo 8oxodGuo, SP-A, SP-D, CC16 and HO-1 were dosed. A lower spirometric values (FEV1 and FVC) were observed among workers compared with controls and the following markers were increased: Si-CAE, 8oxoGuo and HO-1 expression. This study shows that exposure to silica can increase the levels of Si-CAE, which can be used to estimate the dose to the target. Finally, nonspecific spirometric abnormalities and an increase in biomarkers of effect were observed.


Assuntos
Monitoramento Ambiental/métodos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Dióxido de Silício/efeitos adversos , Biomarcadores/análise , Relação Dose-Resposta a Droga , Humanos
6.
G Ital Med Lav Ergon ; 33(3 Suppl): 92-5, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-23393810

RESUMO

Aim of this study was the determination of new markers for the diagnosis of lung cancer. 61 patients with non-small cell lung cancer (NSCLC) and 42 controls were enrolled. In the NSCLC patients the following markers were increased: H2O2 in exhaled breath condensate, pentane, hexane, nonenal, trans-2-heptanal, trans-2-nonenal in exhaled breath, while pentanal was decreased. Using multivariate statistical models, a sensitivity of 73.8% and a specificity of 76.8% were calculated. This study shows that with this non-invasive test followed by a most powerful test on positives (e.g. PET) it is possible to decrease the number of false positives.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/diagnóstico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular
7.
G Ital Med Lav Ergon ; 31(1): 51-3, 2009.
Artigo em Italiano | MEDLINE | ID: mdl-19558040

RESUMO

DNA methylation is a physiological mechanism regulating both gene expression and genomic stability. Abnormal DNA methylation is observed in neoplastic as well as degenerative disease, and may affect both the whole genome and specific genes. Aberrant DNA methylation has been recently associated to the exposure to carcinogenic chemical compounds. The characterization of DNA methylation abnormalities by modern molecular biology methods may allow the development of new molecular biomarkers of early biological effects.


Assuntos
Metilação de DNA , Neoplasias/genética , Neoplasias/prevenção & controle , Humanos
8.
Occup Environ Med ; 64(10): 673-80, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17449559

RESUMO

OBJECTIVES: To investigate associations of Parkinson's disease (PD) and parkinsonian syndromes with polymorphic genes that influence metabolism of either foreign chemical substances or dopamine and to seek evidence of gene-environment interaction effects that modify risk. METHODS: A case-control study of 959 prevalent cases of parkinsonism (767 with PD) and 1989 controls across five European centres. Occupational hygienists estimated the average annual intensity of exposure to solvents, pesticides and metals, (iron, copper, manganese), blind to disease status. CYP2D6, PON1, GSTM1, GSTT1, GSTM3, GSTP1, NQO1, CYP1B1, MAO-A, MAO-B, SOD 2, EPHX, DAT1, DRD2 and NAT2 were genotyped. Results were analysed using multiple logistic regression adjusting for key confounders. RESULTS: There was a modest but significant association between MAO-A polymorphism in males and disease risk (G vs T, OR 1.30, 95% CI 1.02 to 1.66, adjusted). The majority of gene-environment analyses did not show significant interaction effects. There were possible interaction effects between GSTM1 null genotype and solvent exposure (which were stronger when limited to PD cases only). CONCLUSIONS: Many small studies have reported associations between genetic polymorphisms and PD. Fewer have examined gene-environment interactions. This large study was sufficiently powered to examine these aspects. GSTM1 null subjects heavily exposed to solvents appear to be at increased risk of PD. There was insufficient evidence that the other gene-environment combinations investigated modified disease risk, suggesting they contribute little to the burden of PD.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Predisposição Genética para Doença/epidemiologia , Doença de Parkinson/epidemiologia , Doença de Parkinson/genética , Estudos de Casos e Controles , Europa (Continente)/epidemiologia , Feminino , Genótipo , Humanos , Masculino , Razão de Chances , Polimorfismo Genético , Fatores de Risco , Distribuição por Sexo
9.
Occup Environ Med ; 64(10): 666-72, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17332139

RESUMO

OBJECTIVE: To investigate the associations between Parkinson's disease and other degenerative parkinsonian syndromes and environmental factors in five European countries. METHODS: A case-control study of 959 prevalent cases of parkinsonism (767 with Parkinson's disease) and 1989 controls in Scotland, Italy, Sweden, Romania and Malta was carried out. Cases were defined using the United Kingdom Parkinson's Disease Society Brain Bank criteria, and those with drug-induced or vascular parkinsonism or dementia were excluded. Subjects completed an interviewer-administered questionnaire about lifetime occupational and hobby exposure to solvents, pesticides, iron, copper and manganese. Lifetime and average annual exposures were estimated blind to disease status using a job-exposure matrix modified by subjective exposure modelling. Results were analysed using multiple logistic regression, adjusting for age, sex, country, tobacco use, ever knocked unconscious and family history of Parkinson's disease. RESULTS: Adjusted logistic regression analyses showed significantly increased odds ratios for Parkinson's disease/parkinsonism with an exposure-response relationship for pesticides (low vs no exposure, odds ratio (OR) = 1.13, 95% CI 0.82 to 1.57, high vs no exposure, OR = 1.41, 95% CI 1.06 to 1.88) and ever knocked unconscious (once vs never, OR = 1.35, 95% CI 1.09 to 1.68, more than once vs never, OR = 2.53, 95% CI 1.78 to 3.59). Hypnotic, anxiolytic or antidepressant drug use for more than 1 year and a family history of Parkinson's disease showed significantly increased odds ratios. Tobacco use was protective (OR = 0.50, 95% CI 0.42 to 0.60). Analyses confined to subjects with Parkinson's disease gave similar results. CONCLUSIONS: The association of pesticide exposure with Parkinson's disease suggests a causative role. Repeated traumatic loss of consciousness is associated with increased risk.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Doença de Parkinson/epidemiologia , Idoso , Ansiolíticos/uso terapêutico , Antidepressivos/uso terapêutico , Estudos de Casos e Controles , Causalidade , Comorbidade , Traumatismos Craniocerebrais/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Predisposição Genética para Doença/epidemiologia , Humanos , Hipnóticos e Sedativos/uso terapêutico , Modelos Logísticos , Masculino , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Razão de Chances , Doença de Parkinson/genética , Praguicidas , Fatores de Risco , Tabagismo/epidemiologia , Inconsciência/epidemiologia
10.
G Ital Med Lav Ergon ; 27(3): 322-5, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-16240585

RESUMO

Heme oxygenase 1 (HO-1) catalyses the oxidation of heme to biliverdin, and its expression is induced by oxidative stress. This study was aimed at assessing the role of metabolic polymorphisms (CYP1A1, CYP1B1, GSTM1, GSTP1, EPHX) in the modulation of HO-1 gene expression in 37 foundry workers. Blood and urine samples were obtained at the beginning (BS) and at the end (ES) of work shift, in February (T1) and June (T2). Urinary 1-hydroxypyrene (1-OHP) was measured as a tracer of PAH exposure. HO-1 gene expression in ES samples normalized to BS values (HO-1 ES/BS) was higher at T2 respect to T1. HO-1 gene induction was related to ES 1-OHP when considering either T2 samples or the combination of the two samplings. HO-1 ES/BS was significantly increased in subjects with at least a mutant allele for GSTP1 as compared to subjects with GSTP1AA genotype (1.23 +/- 0.002 vs 0.88 +/- 0.002, p < 0.05). Only in subjects with at least one vari.nt allele for GSTP1, a positive correlation between HO-1 ET/IT expression and 1-OHP FT levels was observed (r2 = 0.21, p = 0.016). The present study demonstrates a correlation between PAH exposure, as assessed by urinary 1-OHP, and the induction of HO-1 expression. Such a correlation seems to be limited to subjects bearing variant alleles for GSTP1. At the same exposure levels, these subjects showed a greater expression of HO-1 FT as compared to subjects with GSTP1 wild type genotype, possibly due to a higher oxidative stress in the subjects expressing the mutant GSTP1-1 isoform, which could imply a limited scavenging capacity.


Assuntos
Heme Oxigenase (Desciclizante)/genética , Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Polimorfismo Genético , Pirenos/metabolismo , Adulto , Interpretação Estatística de Dados , Expressão Gênica , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estresse Oxidativo , Pirenos/análise
11.
G Ital Med Lav Ergon ; 27 Suppl 1: 39-42, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-15915653

RESUMO

The delta-aminolevulinate dehydrase (ALAD) genetic polymorphism was investigated along with biomarkers of lead exposure and effect on 333 male workers, occupationally exposed to lead, with blood lead levels (PbB) higher than 100 microg/l. ALAD genotype frequencies were distributed as expected among Caucasians. Workers bearing at least one ALAD-2 allele showed PbB values slightly higher than those from ALAD-1-1 subjects, who also exhibited higher urinary delta-aminolevulinic acid (ALAU) and blood zinc protoporphyrin (ZPP) levels. The plasmatic lead (PbP)/PbB ratio was similar in both groups. Exposure and effect biomarkers were significantly each other correlated among ALAD-1-1 subjects only, who showed also a significant inverse relationship between ALAD activity and ZPP values. Results confirm previous studies, supporting the hypothesis that ALAD polymorphism may interfere with toxico-kinetic and toxico-dynamic parameters of occupational exposure to Pb.


Assuntos
Chumbo/farmacologia , Exposição Ocupacional , Polimorfismo Genético/efeitos dos fármacos , Sintase do Porfobilinogênio/efeitos dos fármacos , Sintase do Porfobilinogênio/genética , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade
12.
Occup Environ Med ; 60(10): 789-93, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14504370

RESUMO

AIMS: To investigate the possible interaction between occupational risk factors and genotype for glutathione S-transferases M1 and T1 (GSTM1 and GSTT1) in renal cell cancer (RCC). METHODS: One hundred patients with RCC and 200 outpatient controls were enrolled at Parma University Hospital. The polymorphisms of glutathione S-transferase M1-1 (GSTM1) and T1-1 (GSTT1) were investigated by PCR; occupational history was collected by a structured questionnaire. RESULTS: Subjects with GSTM1 present genotype showed higher risks for RCC, compared to GSTM1 null subjects, if exposed to metals (OR 2.73; 95% CI 0.91 to 8.22 v 1.14; 95% CI 0.46 to 2.82) or pesticides (OR 3.46; 95% CI 1.12 to 10.74 v 1.59; 95% CI 0.48 to 5.34). The GSTT1 present genotype also enhanced the risk (about twofold) of RCC among subjects exposed to solvents and pesticides, compared with those GSTT1 null. CONCLUSIONS: Results support the hypothesis that GSTM1 and GSTT1 polymorphisms can interact with several occupational exposures to significantly modify the risk of RCC among exposed subjects.


Assuntos
Carcinoma de Células Renais/induzido quimicamente , Glutationa Transferase/genética , Neoplasias Renais/induzido quimicamente , Exposição Ocupacional/efeitos adversos , Solventes/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/enzimologia , Carcinoma de Células Renais/genética , Estudos de Casos e Controles , Indústria Química , Feminino , Predisposição Genética para Doença , Glutationa Transferase/metabolismo , Humanos , Neoplasias Renais/enzimologia , Neoplasias Renais/genética , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo Genético
13.
G Ital Med Lav Ergon ; 25 Suppl(3): 63-4, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-14979085

RESUMO

A cross-sectional study was carried out on laminators producing glass-fibre reinforced plastics, to evaluate the role of genetic polymorphism of xenobiotic metabolising enzymes on the genotoxicity of styrene. Clastogenic effects, evaluated by the micronucleus test, are related with end-of-shift urinary concentration of 4-vinylphenol and seem to be modulated by NQO1 polymorphism; aneuploidogenic effects, evaluated by the identification of centromers in micronuclei using the fluorescence in situ hybridisation technique with a pancentromeric probe, are related with before-shift urinary levels of mandelic and phenylglyoxylic acids and seem to be modulated by the GSTM1 polymorphism.


Assuntos
Enzimas/genética , Polimorfismo Genético , Estireno/farmacocinética , Adulto , Biotransformação , Estudos Transversais , Feminino , Humanos , Masculino , Estireno/toxicidade
14.
Med Lav ; 93(3): 191-201, 2002.
Artigo em Italiano | MEDLINE | ID: mdl-12197269

RESUMO

OBJECTIVES: The present study was aimed at investigating early markers of renal damage and dysfunction in subjects exposed to low doses of mercury from different sources. Different groups of subjects were examined with urinary Hg excretion (HgU) ranging from 0.1 to 35.0 micrograms/g creatinine: 122 occupationally exposed workers, 22 subjects living in a non-polluted area, but consuming large amounts of tuna and sword fish, and 197 controls. METHODS: Several markers of renal changes were measured in urine (albumin, fibronectin, beta 2-microglobulin, retinol-binding protein, tubular antigens, N-acetyl-beta-D-glucosaminidase activity) and serum (beta 2-microglobulin and cystatin C). Serum autoantibodies towards collagen, laminin and tubular antigens were assessed in subjects with abnormal renal markers. The role of glutathione-S-tranferases GSTT1 and GSTM1 polymorphisms in the inter-individual variability of biological response to Hg was also investigated. RESULTS: Renal markers were not correlated with HgU. None of such markers differed significantly between exposed workers and controls, except for urinary beta 2-microglobulin, which was decreased in Hg-exposed workers (GM = 55.8 vs 86.6 micrograms/g creatinine), in the absence of any changes in serum concentration. Subjects usually eating tuna and sword fish showed an increased urinary excretion of beta 2-microglobulin, albumin and fibronectin. Serum titres of auto-antibodies did not differ between the groups. Neither in controls nor in exposed workers were the observed differences modified by the GSTM1 and GSTT1 genotypes. CONCLUSION: The present study did not provide evidence of any changes in kidney integrity and function in subjects exposed to very low levels of inorganic Hg resulting in urinary Hg lower than 35 micrograms/g creatinine. Nor did we obtain evidence of Hg-induced autoimmunity towards kidney components. The potential modifying role of GST polymorphisms could not be clarified in the absence of effects associated with exposure to the risk factor, i.e., to inorganic Hg. Preliminary data suggesting nephrotoxic effects of organic Hg from a diet rich in large fish resulting in increased levels of both blood and urinary Hg--which however did not exceed 20 micrograms/g creatinine--deserves further investigation.


Assuntos
Rim/efeitos dos fármacos , Mercúrio/efeitos adversos , Adulto , Animais , Autoanticorpos/sangue , Biomarcadores/sangue , Biomarcadores/urina , Indústria Química , Relação Dose-Resposta a Droga , Exposição Ambiental , Comportamento Alimentar , Feminino , Contaminação de Alimentos , Predisposição Genética para Doença , Glutationa Transferase/genética , Humanos , Absorção Intestinal , Isoenzimas/genética , Itália/epidemiologia , Masculino , Carne , Mercúrio/administração & dosagem , Mercúrio/farmacocinética , Compostos de Metilmercúrio/administração & dosagem , Compostos de Metilmercúrio/efeitos adversos , Compostos de Metilmercúrio/farmacocinética , Pessoa de Meia-Idade , Exposição Ocupacional , Perciformes , Polimorfismo Genético , Proteinúria/induzido quimicamente , Proteinúria/epidemiologia , Atum
15.
Chem Res Toxicol ; 14(10): 1393-400, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11599931

RESUMO

The role of polymorphic xenobiotic-metabolizing enzymes in the interindividual variability of phenylhydroxyethyl mercapturic acids (PHEMAs) was investigated in 56 styrene-exposed workers. Ambient monitoring was carried out using passive personal samplers (geometric mean, 157 mg/m3 8-h time-weighted average; geometric standard deviation, 2.90). Biomonitoring was based on mandelic acid and phenylglyoxylic acid in urine spot samples collected at the end of the work shift ("end-of-shift") and prior to the subsequent shift ("next morning"). Four PHEMA diastereoisomers, namely (R,R)-M1, (S,R)-M1, (S,R)-M2, and (R,R)-M2, were determined by HPLC/tandem mass spectrometry. The genotypes of glutathione S-transferases M1-1 (GSTM1), T1-1 (GSTT1) and P1-1 (GSTP1), and microsomal epoxide hydrolase (EPHX) were characterized by PCR-based methods. Workers bearing the GSTM1pos genotype showed PHEMA concentrations five and six times higher (in end-of-shift and next-morning samples, respectively) as compared to GSTM1null people. In GSTM1pos subjects, (R,R)-M1 was the main mercapturate affected by the GSTM1 status, accounting for 54 and 68% of total PHEMAs in end-of-shift and next-morning samples, respectively. Compared to GSTM1null, GSTM1pos subjects excreted more -M1 than -M2 and more (R,R)-M1 and (S,R)-M2 than (S,R)-M1 and (R,R)-M2 diastereoisomers. Thus, GSTM1-1 is the main isoenzyme catalyzing GSH-conjugation of styrene-7,8-oxide in humans and it seems to act in a regio- and stereoselective way. PHEMAs cannot be recommended as biomarkers of exposure to styrene, unless the GSTM1 genotype is considered in data interpretation. Their role as biomarkers of susceptibility deserves further studies.


Assuntos
Acetilcisteína/urina , Carcinógenos/metabolismo , Epóxido Hidrolases/metabolismo , Compostos de Epóxi/metabolismo , Sequestradores de Radicais Livres/urina , Glutationa Transferase/metabolismo , Exposição Ocupacional , Polimorfismo Genético , Estireno/metabolismo , Acetilcisteína/metabolismo , Adulto , Biomarcadores/análise , Carcinógenos/química , Carcinógenos/farmacocinética , Catálise , Cromatografia Líquida de Alta Pressão , Epóxido Hidrolases/genética , Compostos de Epóxi/química , Compostos de Epóxi/farmacocinética , Feminino , Sequestradores de Radicais Livres/metabolismo , Glutationa Transferase/genética , Humanos , Isoenzimas , Masculino , Espectrometria de Massas , Estireno/farmacocinética , Xenobióticos
16.
Am J Respir Crit Care Med ; 163(6): 1426-31, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11371413

RESUMO

The role of the genetic polymorphism of NAD(P)H:quinone oxidoreductase (NQO1) and glutathione-S-transferase micro-1 (GSTM1) in the responsiveness to O(3)-induced acute effects was investigated in 24 healthy nonsmokers performing 2-h bike rides at ambient O(3) varying from 32 to 103 ppb. Before and after rides, each subject performed spirometric tests and provided a blood sample for the measurement of the Clara cell protein CC16. NQO1 and GSTM1 polymorphisms were characterized by polymerase chain reaction- based methods. The 8-hydroxy-2'-deoxyguanosine (8-OHdG) adduct was also measured in DNA of peripheral leukocytes. Rides at O(3) > 80 ppb resulted in significant decrements of pulmonary function tests and increased levels of serum CC16, consistent with mild impairment in respiratory function and increased lung epithelial permeability, respectively. Whereas NQO1wt and GSTM1null subjects showed both functional changes and increased serum CC16 after acute O(3) exposure, people with other haplotypes showed a rise in serum CC16 but no changes in lung function tests. In NQO1wt and GSTM1null subjects, partial correlation analysis showed that functional decrements and increased serum CC16 are closely associated with each other and with O(3) levels, whereas no such relationships were found among subjects bearing other haplotypes. An increased reaction rate between O(3) and hydroquinones would be consistent with the greater increase in 8-OHdG after O(3) exposure in this "susceptible" group.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Benzoquinonas/metabolismo , Hiper-Reatividade Brônquica/induzido quimicamente , Hiper-Reatividade Brônquica/genética , Desoxiguanosina/análogos & derivados , Exposição Ambiental/efeitos adversos , Glutationa Transferase/genética , NAD(P)H Desidrogenase (Quinona)/genética , Oxidantes Fotoquímicos/efeitos adversos , Ozônio/efeitos adversos , Uteroglobina , 8-Hidroxi-2'-Desoxiguanosina , Doença Aguda , Adulto , Hiper-Reatividade Brônquica/diagnóstico , Hiper-Reatividade Brônquica/metabolismo , Feminino , Frequência do Gene , Genótipo , Haplótipos , Heterozigoto , Homozigoto , Humanos , Masculino , Reação em Cadeia da Polimerase , Proteínas
17.
Toxicol Lett ; 108(2-3): 241-7, 1999 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-10511268

RESUMO

A quasi-experimental field study was carried out in 24 volunteers with the aim of: (i) assessing personal exposure to aromatic hydrocarbons polluting urban areas; and (ii) exploring the role of polymorphic enzymes relevant to the biotransformation of benzene in the inter-individual variability of biomarkers. Each subject covered by bicycle: (i) inner city routes with often jammed traffic; and (ii) open rural routes. Time-weighted average airborne concentrations of benzene, toluene, ethylbenzene and xylenes (BTEX) were determined during 2-h runs. BTEX were determined by solid-phase micro-extraction (SPME) followed by gas chromatography coupled with mass spectrometry (GC-MS) in blood and spot urine samples collected just before and immediately after the runs. Urinary t,t-muconic acid was measured by high performance liquid chromatography (HPLC)-UV. Genotypes of epoxide hydrolase (EH) and glutathione-S-transferase class mu-1 (GSTM1) were also characterised. As compared to pre-run values, benzene and toluene in blood, and toluene and xylenes in urine significantly increased after urban runs. Urinary t,t-muconic acid was significantly higher in post-run samples after both urban (P < 0.001) and rural runs (P < 0.05). Despite a narrow range of exposure levels, a significant relationship was observed between airborne benzene and post-run t,t-muconic acid (r2 = 0.349, P < 0.00). When subgroups were distinguished according to EH and GSTM, subjects bearing both the EH wild type and GSTM 'null' genotype showed significant exposure-related changes in t,t-muconic acid excretion. Even at very low exposure levels, a 2-h bike run in a polluted urban environment may give rise to measurable changes in biomarkers of internal dose of selected aromatic hydrocarbons. Genetically-based metabolic differences may account for part of the inter-individual variability of biomarkers of exposure.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Hidrocarbonetos Aromáticos/análise , Adulto , Benzeno/análise , Derivados de Benzeno/sangue , Ciclismo , Biomarcadores/sangue , Biomarcadores/urina , Feminino , Humanos , Hidrocarbonetos Aromáticos/sangue , Masculino , Saúde da População Rural , Fatores Sexuais , Ácido Sórbico/análogos & derivados , Ácido Sórbico/análise , Tolueno/sangue , Saúde da População Urbana , Xilenos/sangue
18.
Ren Fail ; 21(3-4): 369-85, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10416216

RESUMO

The association between hydrocarbon exposure and chronic glomerulonephritis is still a controversial scientific issue. Recent epidemiological evidence suggests a role of exposure to hydrocarbons in the progression of glomerulonephritis towards chronic renal failure. The present experimental study on rats has been designed to assess the possible role of styrene in the progression of adriamycin (ADR) nephrosis, a well known model of renal fibrosis following nephrotic syndrome induced by ADR. Female Sprague-Dawley rats were exposed to styrene, 300 ppm, 6 h/day, 5 days/week for 12 weeks (group 1); treated with ADR, 2 mg/Kg, i.v., twice on day 1 and day 15 of the study (group 2); Additional groups of animals received both the styrene and ADR treatments (group 3) or served as controls (group 4). The urinary excretion of total and single proteins (albumin, Retinol-Binding Protein (RBP), Clara Cell 16 Kd protein (CC16), fibronectin) was measured monthly, whereas histopathology and determinations requiring blood sampling were carried out at the end of the experiment. A progressive increase in total proteinuria, falling in the nephrotic range already by the 6th week was observed in ADR-treated groups. Styrene exposure caused up to a 3- to 5-fold increase as compared to controls. Co-exposure to ADR and styrene also resulted in a proteinuria much greater than that caused by ADR alone. The interactive effect of styrene and ADR was statistically significant for albuminuria and urinary fibronectin. A similar response was observed for glomerular filtration rate at the end of the experiment, styrene-exposed animals showing hyperfiltration as compared to their respective control group. At the end of the experiment, histopathological scoring for interstitial infiltration and fibrosis was also significantly higher in styrene-treated animals as compared to their respective control groups. In ADR-treated rats, low molecular weight proteinuria (l.m.w.p.) was only slightly affected, suggesting minimal tubular dysfunction associated with extensive tubular atrophy. However, styrene-exposed animals showed l.m.w.p. higher than their respective controls. In summary, in this animal model we were able to confirm both styrene-induced microproteinuria, mainly albuminuria and minor increases in l.m.w.p., observed among occupationally exposed workers and the role of hydrocarbon exposure as a factor accelerating the progression of renal disease suggested by epidemiological investigations in patients suffering from chronic renal disease. Whereas in rats exposed to styrene only, microproteinuria was stable over time and minor histopathological changes were noted at the end of the experiment, evidence of a role of solvent exposure in the progression of ADR nephropathy was obtained in terms of both renal dysfunction and interstitial fibrosis. The mechanistic basis of styrene-ADR interaction is unclear. However, experimental evidence is consistent with epidemiological findings suggesting the need to avoid solvent exposure in patients suffering from renal diseases.


Assuntos
Antineoplásicos/toxicidade , Doxorrubicina/toxicidade , Glomerulonefrite/induzido quimicamente , Hidrocarbonetos/toxicidade , Solventes/toxicidade , Estireno/toxicidade , Albuminúria/induzido quimicamente , Albuminúria/urina , Animais , Doença Crônica , Modelos Animais de Doenças , Feminino , Fibronectinas/urina , Glomerulonefrite/urina , Rim/efeitos dos fármacos , Rim/fisiopatologia , Proteinúria/induzido quimicamente , Proteinúria/urina , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
20.
Nat Biotechnol ; 15(2): 155-8, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9035141

RESUMO

Single chain fragment (ScFv) antiidiotypic antibodies (antilds) of a killer toxin (KT) from the yeast Pichia anomala have been produced by recombinant DNA methodology from the splenic lymphocytes of mice immunized by idiotypic vaccination with a KT-neutralizing monoclonal antibody (Mab KT4). ScFv KT-like antilds (KTIdAb) react with specific Candida albicans KT cell wall receptors (KTR) exerting a candidacidal activity in vitro could be neutralized by adsorption with Mab KT4. ScFv KTIdAb displayed an effective therapeutic activity in an experimental model of rat candidal vaginitis.


Assuntos
Anticorpos Anti-Idiotípicos , Anticorpos Monoclonais , Candidíase Vulvovaginal/tratamento farmacológico , Imunotoxinas/uso terapêutico , Micotoxinas/uso terapêutico , Animais , Candida albicans/efeitos dos fármacos , Candida albicans/imunologia , Candida albicans/fisiologia , DNA Recombinante , Desenho de Fármacos , Feminino , Engenharia Genética , Imunotoxinas/farmacologia , Fatores Matadores de Levedura , Camundongos , Testes de Sensibilidade Microbiana , Micotoxinas/biossíntese , Micotoxinas/farmacologia , Pichia , Ratos
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