Diana Poli

Università degli studi di Parma, Parma, Emilia-Romagna, Italy

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Publications (47)120.56 Total impact

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    ABSTRACT: The aim of this work was to evaluate the oxidative damage to nucleic acids in children (5-11 years) associated with exposure to environmental pollutants and tobacco smoke (ETS). For each subject, urinary sampling was done twice (evening and next morning) to measure by tandem LC-MS-MS such oxidated products of nucleic acids as 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo), 8-oxo-7,8-dihydroguanosine (8-oxoGuo), and 8-oxo-7,8-dihydroguanine (8-oxoGua). Methyl tert-butyl ether (U-MTBE), benzene (U-Benz), and its metabolites (t,t-muconic and S-phenylmercapturic acids, t,t-MA and S-PMA, respectively) were determined as biomarkers of exposure to air pollution, and cotinine as a biomarker of exposure to ETS. Biomarkers of exposure (S-PMA and U-MTBE) and of DNA oxidation (8-oxodGuo) were dependent on the urbanization and industrialization levels and increased in the evening sample as compared to next morning (p<0.05). In both evening and next morning samples, 8-oxodGuo and 8-oxoGuo correlated with each other (r=0.596 and r=0.537, respectively, p<0.01) and with biomarkers of benzene exposure, particularly S-PMA (r=0.59 and r=0.45 for 8-oxodGuo and r=0.411 and r=0.383 for 8-oxoGuo, p<0.01). No such correlations were observed for U-MTBE and cotinine. Multiple linear regression analyses showed that 8-oxodGuo was positively associated with S-PMA at both sampling times (β=0.18 and β=0.14 for evening and next morning sampling, respectively; p<0.02) and weakly with U-MTBE (β=0.07, p=0.020) only in the evening urines. These results suggest that the selected biomarkers of exposure to benzene, particularly S-PMA, are good tracers of exposure to complex mixtures of oxidative pollutants and that the associated oxidative damage to nucleic acids is detectable even at very low levels of exposure. Copyright © 2015 Elsevier Inc. All rights reserved.
    No preview · Article · Jul 2015 · Environmental Research
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    ABSTRACT: 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.
    No preview · Article · May 2015 · Journal of Breath Research
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    ABSTRACT: 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.
    No preview · Article · Feb 2013 · Giornale italiano di medicina del lavoro ed ergonomia
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    ABSTRACT: This cross-sectional study was aimed at reconstructing the exposure to gasoline in 102 petrol station attendants by environmental and biological monitoring of benzene, toluene, ethylbenzene and xylene (BTEX) and biomonitoring of methyl tert-butyl ether (MTBE). Airborne BTEX were higher for manual refuelers than self-service assistants and were highly correlated with each other. Significant relationships were found between airborne BTX and the corresponding urinary solvents (U-BTX) and beween airborne B and urinary MTBE (U-MTBE). Smokers eliminated higher values of U-B, trans,trans-muconic (t,t-MA) and S-phenylmercapturic (S-PMA) acids but not U-MTBE. All these biomarkers were, however, significantly raised during the shift, independently from smoking. Linear regression confirmed that occupational exposure was a main predictor of U-MTBE, U-B and S-PMA values, both the latter confounded by smoking habits. The study supports the usefulness of biomonitoring even at low exposure levels.
    No preview · Article · Mar 2012 · Biomarkers
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    ABSTRACT: PM(2.5) generated by indoor combustion activities can contribute significantly to personal PM exposure. The aims of this study were: (1) to validate a device specifically designed to study the kinetics of particle exhalation and the percentage of airway particle deposition (%DEP) in polluted indoor environments (welding fumes, environmental tobacco smoke - ETS) and (2) to assess the intra- and inter-subject variability of the signal. The device was tested on 14 subjects exposed to welding fumes and 10 subjects exposed to environmental tobacco smoke (ETS), performing repeated measures at different environmental PM concentrations. The intra-subject variability of the signal for particles with diameter 0.3-1.0 μm showed a geometric mean of %CV always below 6%, despite the values of %DEP. In the welding fume study, the increase in airborne 0.5-1.0 μm PM concentrations between the consulting room and production department was explainable in terms of increased density due to the metallic composition of particles. The %DEP of 0.3-1.0 μm ETS particles decreased with airborne PM concentration due to the technical limits of a laser particle counter and the perturbation induced by the physical characteristics of ETS PM. However, also at those extreme conditions, the signal remained repeatable and the individual susceptibility to PM remained substantially unaltered. In conclusion, the versatility and portability of our device, together with the repeatability of the signal, confirmed that the kinetics of exhaled particles and %DEP could be routinely measured in polluted environments and used to define individual susceptibility to airborne particles.
    No preview · Article · Dec 2011 · International journal of hygiene and environmental health
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    ABSTRACT: 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.
    No preview · Article · Jul 2011 · Giornale italiano di medicina del lavoro ed ergonomia
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    ABSTRACT: MeHg (0.5 mg/kg/day) and/or PCB153 (5 mg/kg/day) effects, administered orally to rat dams (GD7-PND21), were explored in PND21 and PND36 offspring brain in terms of density (Bmax) and affinity (Kd) of dopamine D1-like (D1-Rs) and D2-like receptors (D2-Rs), by saturation binding studies. D1-Rs decreased density in both cortex and striatum (15-30%) by MeHg and PCB153, either alone or combined, without additivity in PND21 males. Changes disappeared by PND36. In females, only MeHg caused a 15% Bmax decrease in striatum. D2-Rs enhanced density (23-50%) and reduced affinity in cortex to a similar extent by all treatments in both weanling and pubertal males. Affinity was also decreased in females by all types of exposure at both ages, while density was enhanced by PCB153 only in a delayed manner (PND36). No changes were detected in striatum. In MeHg and MeHg + PCB153 pup cortex, Hg concentrations ranged, on PND21, between 0.25 and 0.89 and 0.94-1.40 μg/g tissue, respectively, and were 5- to sixfold lower 2 weeks later. PCB153 levels, in PCB153 ± MeHg treated rats, were about 15 μg/g tissue (PND21) and 4-8 μg/g tissue (PND36). In striatum, the Hg and PCB153 concentrations were similar to those in cortex. Brain kinetics trend also applied to blood PCB153 or Hg levels. Perinatal exposure to MeHg and/or PCB153 affects D1- and D2-Rs in a gender-, time-, and brain area-dependent manner. Combined treatment does not exacerbate the neurochemical effects of the individual compounds.
    No preview · Article · Feb 2011 · Archives of Toxicology
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    ABSTRACT: A number of volatile organic compounds (VOCs) have been identified and used in preliminary clinical studies of the early diagnosis of lung cancer. The aim of this study was to evaluate the potential of aldehydes (known biomarkers of oxidative stress) in the diagnosis of patients with non-small cell lung cancer (NSCLC). We used an on-fiber-derivatisation SPME sampling technique coupled with GC/MS analysis to measure straight aldehydes C3-C9 in exhaled breath. Linearity was established over two orders of magnitude (range: 3.3-333.3×10(-12) M); the LOD and LOQ of all the aldehydes were respectively 1×10(-12) M and 3×10(-12) M. Accuracy was within 93% and precision calculated as % RSD was 7.2-15.1%. Aldehyde stability in a Bio-VOC(®) tube stored at +4°C was 10-17 h, but this became >10 days using a specific fiber storage device. Finally, exhaled aldehydes were measured in 38 asymptomatic non-smokers (controls) and 40 NSCLC patients. The levels of all of the aldehydes were increased in the NSCLC patients without any significant effect of smoking habits and little effect of age. The good discriminant power of the aldehyde pattern (90%) was confirmed by multivariate analysis. These results show that straight aldehydes may be promising biomarkers associated with NSCLC, and increase the sensitivity and specificity of previously identified VOC patterns.
    Full-text · Article · Oct 2010 · Journal of chromatography. B, Analytical technologies in the biomedical and life sciences
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    ABSTRACT: During a routine truck-tank washing operation, five healthy workers were found motionless inside an empty tanker. Four of them died inside the tanker while the fifth died the following day in hospital. Since the true nature of the fatal compound(s) were not known, a rigorous environmental and toxicological approach supported by autopsy findings was essential to clarify the cause of death. Environmental results indicated that H(2)S fumes arising from the liquid sulfur previously shipped were responsible for the serial deaths, also confirmed by a simulation performed on two similar truck-tanks. These environmental findings were supported by toxicological analyses through the measurement of thiosulfate, one of the main H(2)S metabolites. Abnormal thiosulfate concentrations from 1.1 to 186.2 mg/kg were revealed in all post-mortem biological samples (blood, lung, liver, kidney, brain and fat). Finally, the cluster analysis performed on thiosulfate body distribution contributed to establishing the time of death according to the accident scene reconstruction. This report presents valuable findings in correctly identifying the cause of death in gas asphyxiation cases by unknown compound(s).
    Full-text · Article · Apr 2010 · Forensic science international
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    ABSTRACT: This study investigated nucleic acid oxidation associated with exposure to benzene at low levels in 239 workers recruited among traffic policemen, taxi drivers and gasoline pump attendants of the city of Parma (Italy). Biomarkers of exposure, namely urinary t,t-muconic acid (t,t-MA) and S-phenylmercapturic acid (S-PMA), urinary cotinine, and urinary biomarkers of nucleic acid oxidation, namely 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo), 8-oxo-7,8-dihydroguanosine (8-oxoGuo) and 8-oxo-7,8-dihydroguanine (8-oxoGua) were determined by liquid chromatography-tandem mass spectrometry. Relevant polymorphisms of NAD(P)H:quinone oxidoreductase (NQO1), glutathione S-transferases M1-1 (GSTM1), T1-1 (GSTT1), and A1 (GSTA1) were characterized by polymerase chain reaction-based methods in a subgroup of subjects. Biomarkers of nucleic acid oxidation were correlated with each other (r> or =0.32, p<0.0001) and with exposure biomarkers (r> or =0.28, p<0.0001). Multiple linear regression models including age, sex and smoking habits as independent variables demonstrated that benzene exposure is associated with oxidation damage to nucleic acid, particularly to RNA (p<0.0001) and is modulated by the NQO1 polymorphism. The study confirmed a significant modulating effect of GSTM1 (p=0.010), GSTT1 (p=0.023) and GSTA1 (p=0.048) polymorphisms on S-PMA excretion, with a significant interaction between GSTM1 and both GSTT1 and GSTA1 (p=0.006 and p=0.037, respectively).
    No preview · Article · Apr 2010 · Toxicology Letters
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    ABSTRACT:   In a public hospital, eight cases of fatal poisoning by nitrous oxide (N2O) occurred under oxygen administration, due to an erroneous swapping of the lines in the gas system. The aim of the study was to clarify the factors involved in asphyxia by characterizing gases from different lines and measuring N2O concentrations in postmortem biological samples from bodies exhumed. Analyses carried out on the gas system confirmed the erroneous substitution of O2 line with N2O and air line with O2. Consequently, high N2O amounts were revealed in several tissues and gaseous biological samples. All specimens were analyzed by headspace gas chromatography technique. A rigorous quantitative analysis was possible only in blood (11.29–2152.04 mg/L) and urine (95.11 mg/L) and in air samples from stomach and trachea (from 5.28 to 83.63 g/m3). This study demonstrates that N2O can be detected in biological samples even 1 month after death.
    No preview · Article · Dec 2009 · Journal of Forensic Sciences
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    ABSTRACT: Polybrominated diphenyl ether (PBDE) flame retardants have become widespread environmental contaminants. The highest body burden has been found in toddlers and infants, due to their exposure through breast milk and house dust, and the current concern for potential adverse health effects of PBDEs relates to their developmental neurotoxicity. The mechanisms underlying the neurotoxicity of PBDEs are largely not understood, though there is evidence that PBDEs may elicit oxidative stress. In this study, two different mathematical models were used to evaluate the interaction between BDE-47 and BDE-99 on viability of neuronal cells. The combined exposure to these compounds induced synergistic effects at concentrations of BDE-47 below its threshold doses, and in a wide range of BDE-99 concentrations below its IC(50). In contrast, at concentrations of BDE-47 near its IC(50) value, and in a wide range of BDE-99 concentrations, antagonistic effects were observed. The interactions observed on cell viability were confirmed by an assessment of induction of oxidative stress. The finding that co-exposure to BDE-47 and BDE-99 could induce synergistic neurotoxic effects, in particular at low doses of BDE-47, is of much toxicological interest, as humans are exposed to mixtures of PBDEs, most notably tetra- and penta-BDE congeners.
    No preview · Article · Sep 2009 · Toxicology in Vitro
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    ABSTRACT: The aim of this study was to assess and monitor airway exhalation and deposition of particulate matter (PM). After standardizing inspiratory/expiratory flow and volumes, a novel device was tested on a group of 20 volunteers and in a field study on workers exposed to cristobalite. Both male and female subjects showed a higher percentage of deposition in the 0.5 microm channel than in the 0.3 microm channel on a laser particle counter, but it was higher in the males because of their higher exhaled lung volumes. The device was tested on a wider range of particles (0.3-0.5-1.0-2.5 microm) in the cristobalite productive division. The device has low intrasubject variability and good reproducibility, with geometric mean of %CV < 5%. Such a measure can be used to assess individual susceptibility to PM, making repeated measures in different environments, and examining the persistence of particles in the airways after a period in polluted environments.
    No preview · Article · May 2009 · Biomarkers
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    ABSTRACT: A simple and reliable solid phase microextraction/gas chromatography-mass spectrometry (SPME/GC-MS) method was developed for the single-step determination of PCBs 126 and 153 in rat brain and serum, using liquid/liquid and solid phase extraction (SPE) as reference techniques. The multi-factor categorical experimental design used to study simultaneously the main parameters and their interactions affecting the efficiency of the method, showed that the use of an 85mum PA exposed at 100 degrees C for 40min was the optimum sampling condition for both PCBs. SPME was then validated by studying its linear dynamic (over two orders of magnitude), limits of detection (brain: 2ng/g, serum: 0.2ng/g) and analytical precision that was within 9% for SPME in both brain and serum. Finally, the method was used to determine the brain and blood target dose in mothers and pups after oral exposure of the mothers.
    No preview · Article · Mar 2009 · Journal of chromatography. B, Analytical technologies in the biomedical and life sciences
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    ABSTRACT: A comparative evaluation of urinary biomarkers was carried out to characterize benzene exposure in a group of 100 traffic policemen of the city of Parma (Italy). All subjects were monitored once, in two consecutive days characterized by similar climatic conditions but preceded by two windy days. Benzene ambient concentration measured by municipal air monitoring stations was 1 microg/m(3) (Day 1) and 2 microg/m3 (Day 2). Personal exposure to ambient concentrations of benzene, toluene, ethylbenzene and xylene (BTEX) was assessed by using Radiello((R)) passive-diffusive samplers in a subgroup of 24 workers. Benzene metabolites, t,t-muconic acid (t,t-MA) and S-phenylmercapturic acid (S-PMA) were determined by isotopic dilution liquid chromatography-tandem mass spectrometry on spot urine samples collected at the end of the shift. Urinary benzene (U-B) was determined by solid-phase microextraction gas chromatography-mass spectrometry. Airborne benzene concentration expressed as median [and interquartile range] was 6.07 [0.28-9.53] microg/m(3), as assessed by personal sampling. Urinary concentrations of biomarkers in the whole group were 41.8 [34.1-89.8] microg/g creatinine for t,t-MA, 0.67 [0.23-1.32] microg/g creatinine for S-PMA, and 0.16 [0.13-0.26] microg/l for U-B. Smokers eliminated significantly higher concentrations of unchanged BTEX and benzene metabolites than non-smokers (p < 0.05). When traffic policemen were distinguished into indoor (n=31) and outdoor workers, no significant differences were observed for either airborne benzene or urinary biomarkers. Significantly lower concentrations of S-PMA and U-B were determined in samples collected at Day 1 as compared to Day 2 (p < 0.0001 and p = 0.003, respectively) suggesting that these biomarkers are enough sensitive and specific to detect changes in airborne benzene concentration even at few microg/m(3).
    No preview · Article · Sep 2008 · Toxicology Letters
  • M Corradi · D Poli · M Goldoni
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    ABSTRACT: Individuals who have been exposed to lung carcinogenics are concerned by their greater risk of developing lung cancer, thus consult physicians with the expectation of undergoing screening tests. Controversy remains as to which screening procedures should be assessed. Previous studies of sputum cytology and chest X-rays showed no benefits in lung cancer mortality reduction. Screening of high risk individuals through computerized tomography scan appeared promising, but this radiological technique suffers from low specificity. Currently, the differential diagnosis is mainly based on additional imaging techniques, particularly positron emission tomography, which is expensive, and also shows limitations in terms of sensitivity and specificity. Therefore, purely morphological criteria seem to be insufficient to distinguish lung cancer at early stages from benign nodules with sufficient confidence, and false positives undergoing surgical resection seem to occur frequently. A molecular approach to the diagnosis of lung cancer through the analysis of biomarkers obtained by non invasive means could greatly improve the specificity of imaging procedures. Extremely sensitive mass spectrometric techniques are available to detect molecular alterations in accessible media, which characterise lung cancer at early stages, thereby reducing the rate of false positives, expected to be very out without a sound application of confirmatory diagnostic tests.
    No preview · Article · Jul 2008 · Giornale italiano di medicina del lavoro ed ergonomia
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    ABSTRACT: Chromium in exhaled breath condensate (EBC) has recently been proposed as a biomarker of pulmonary exposure. The aim of this study was to measure the Cr levels in the EBC and pulmonary tissue of patients with early, operable non-small cell lung cancer (NSCLC) who had not been occupationally exposed to Cr before and after tumour resection and to correlate Cr in lung tissue with that in EBC. Cr levels in the EBC and pulmonary tissue of 20 NSCLC patients were measured by means of electrothermal atomic absorption before and after tumour resection. Cr levels were also measured in the urine of 15 of these patients. The pre-surgery EBC Cr levels of the NSCLC patients were not different from those of the controls, but both EBC and urinary Cr levels increased after surgery. There was a significant correlation between Cr levels in EBC and pulmonary tissue (R = 0.55, P = 0.01), but not between these and urinary Cr levels. Cr levels in EBC and urine of NSCLC patients were increased after surgical intervention. Measured Cr EBC levels were by one order of magnitude lower than those observed in moderately exposed workers. This fact, together with the correlation between Cr in EBC and in pulmonary tissue, confirms that EBC is a promising biological fluid to test pulmonary exposure to Cr, giving complementary information to that provided by urinary Cr, not correlated with EBC and tissue.
    No preview · Article · Mar 2008 · International Archives of Occupational and Environmental Health
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    ABSTRACT: Exhaled breath condensate (EBC) consists mainly of water, but also contains semivolatile and nonvolatile compounds. The aim of this study was to develop a system in which two condensers are simultaneously used in series to clarify the mechanisms of EBC condensation. Two aliquots of EBC (EBC1 and EBC2) were collected from 20 asymptomatic smokers and 20 healthy young nonsmokers using a specifically designed device having two condensers in series in which total volume, hydrogen peroxide (H(2)O(2)), ammonium (NH(4)(+)), and conductivity before and after lyophilization were measured. Water, NH(4)(+) levels and conductivity before lyophilization were significantly lower in the EBC2 than in the EBC1 of smokers and nonsmokers; the contrary was true for H(2)O(2) levels. Almost all nonvolatile salts were collected in the first condenser, because more than 50% of postlyophilization conductivity was below the detection limit in EBC2. The recovery of volatile molecules and their derivatives (water and NH(4)(+)) was partial in the first condenser, but appreciable amounts of both were measured in the second; however, the condenser immediately in contact with exhaled air was more efficient in terms of water, NH(4)(+) and conductivity before lyophilization. On the contrary, nonvolatile ions (conductivity after lyophilization) were mainly collected in the first condenser. Finally, the behavior of H(2)O(2) cannot be explained on the basis of its chemical and physical properties, and the most probable explanation is that some was byproduced by a radical reaction in the gas phase or during the condensation process in water.
    No preview · Article · Mar 2008 · Journal of Aerosol Medicine and Pulmonary Drug Delivery
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    ABSTRACT: Me-Hg and PCB153 are known neurotoxic contaminants which tend to accumulate in food, particularly in fish. Aim of this study was to perform asynchronous and combined exposure to Me-Hg and PCB153 in a neuronal rat cell line (PC12) to better characterise the antagonism observed at some combination concentrations. PC12 cells were treated with three concentrations of Me-Hg (0.1-0.5-1.0 microM) and PCB153 at one concentration (175 microM) in single and combined asynchronous exposures, using viability (MTT assay) as end-point. At all concentrations used, a statistically significant antagonistic effect was observed when Me-Hg preceded PCB153 exposure, while effect was additive when PCB153 preceded Me-Hg exposure. The antagonism is particularly evident at low concentrations of Me-Hg (0.1 microM). In conclusion, combined asynchronous exposure showed that whereas Me-Hg can modulate PCB153 toxicity, the opposite seems not to be true. Therefore, the use of asynchronous exposure could be a promising approach to study the mechanisms of toxicity of binary mixtures.
    Full-text · Article · Mar 2008 · Food and Chemical Toxicology
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    ABSTRACT: Exhaled breath condensate (EBC) consists mainly of water, but also contains semivolatile and nonvolatile compounds. The aim of this study was to develop a system in which two condensers are simultaneously used in series to clarify the mechanisms of EBC condensation. Two aliquots of EBC (EBC1 and EBC2) were collected from 20 asymptomatic smokers and 20 healthy young nonsmokers using a specifically designed device having two condensers in series in which total volume, hydrogen peroxide (H(2)O(2)), ammonium (NH(4)(+)), and conductivity before and after lyophilization were measured. Water, NH(4)(+) levels and conductivity before lyophilization were significantly lower in the EBC2 than in the EBC1 of smokers and nonsmokers; the contrary was true for H(2)O(2) levels. Almost all nonvolatile salts were collected in the first condenser, because more than 50% of postlyophilization conductivity was below the detection limit in EBC2. The recovery of volatile molecules and their derivatives (water and NH(4)(+)) was partial in the first condenser, but appreciable amounts of both were measured in the second; however, the condenser immediately in contact with exhaled air was more efficient in terms of water, NH(4)(+) and conductivity before lyophilization. On the contrary, nonvolatile ions (conductivity after lyophilization) were mainly collected in the first condenser. Finally, the behavior of H(2)O(2) cannot be explained on the basis of its chemical and physical properties, and the most probable explanation is that some was byproduced by a radical reaction in the gas phase or during the condensation process in water.
    No preview · Article · Feb 2008 · Journal of Aerosol Medicine