[Show abstract][Hide abstract] ABSTRACT: Industrial air pollution is a public health hazard. Previous evidence documented increased respiratory symptoms and hospitalizations in children who live near the factories in the largest chipboard manufacturing district in Italy (Viadana).
To evaluate the association of outdoor exposure to formaldehyde and NO2 with markers of early genotoxic damage in oral mucosa cells of randomly selected children (6-12 years) living in Viadana.
In 2010-2011, DNA strand breaks and nuclear abnormalities were evaluated in exfoliated buccal cells by the comet and micronucleus assays, respectively, and formaldehyde and NO2 were monitored by passive sampling. Annual exposure estimates to pollutants were assigned to children's houses by spatial interpolation.
413 out of 656 (63%) children participated. Children living near (<2 km) the chipboard industries had the highest average exposure to formaldehyde and NO2 (p<0.001). A 1-standard deviation (SD) increase in formaldehyde (0.20 μg/m(3)) was associated with a 0.13% (95% CI: 0.03, 0.22%) higher comet tail intensity, a 0.007 (95% CI: 0.001, 0.012) higher tail moment, and a 12% relative increase (RR=1.12; 95% CI: 1.02, 1.23) in nuclear buds. A 1-SD NO2 increase (2.13 µg/m(3)) was associated with a 0.13% (95% CI: 0.07, 0.19%) increase in binucleated cells and a 16% relative increase (RR=1.16; 95% CI: 1.06, 1.26) in nuclear buds.
Exposure to pollutants was associated with markers of genotoxicity in exfoliated buccal cells of children living in a region with chipboard industries. These findings, combined with previously reported associations between chipboard industrial activities and respiratory outcomes in children, add to concerns about potential adverse effects of industry-related exposures in the Viadana district.
Environmental Health Perspectives 04/2014; 122(6). DOI:10.1289/ehp.1307259 · 7.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To study the validity of urinary benzene as a biomarker of low and very low exposure to this toxicant, as compared with t,t-muconic acid (t,t-MA) and S-phenylmercapturic acid (SPMA), also taking into account the influence of cigarette smoking and co-exposure to toluene on the urinary excretion of benzene.
The results obtained in two different studies were compared: in the first, workers occupationally exposed to low concentrations of benzene (18 fuel tanker drivers and 23 filling station attendants) were compared with 31 controls and in the second, workers exposed to very low concentrations of benzene (the same 23 filling station attendants) were compared with the 31 controls. Exposure to airborne benzene and toluene was monitored with passive personal samplers (Radiello). Then the urine collected at the end of the work shift was analyzed for t,t-MA, SPMA and urinary benzene. All participants also filled out a questionnaire about their lifestyle habits.
There were no differences among the three groups in terms of age and smoking habit. Occupational exposure to benzene and toluene and the urinary concentrations of t,t-MA, SPMA and urinary benzene were higher in the fuel tanker drivers than the filling station attendants and higher in the latter than in the controls. Cigarette smoking was found to be associated with urinary excretion of t,t-MA, SPMA and urinary benzene at both low and very low exposure to benzene. The biomarkers t,t-MA, SPMA and urinary benzene were almost always correlated, for both low and very low exposure to benzene. Notably, for low exposure to benzene a dependency relation was found with the levels of t,t-MA, SPMA and urinary benzene on both cigarette smoking and airborne benzene, whereas for very low exposure to benzene there was a dependency relation of SPMA on cigarette smoking and airborne benzene, of urinary benzene only on cigarette smoking and of t,t-MA on none of the variables considered.
For occupational exposure to low concentrations of benzene, urinary benzene and SPMA showed a comparable validity, while for exposure to very low concentrations of this toxicant the validity of SPMA was confirmed while urinary benzene was found to be less useful. Cigarette smoking was the main factor conditioning the excretion of all the biomarkers of benzene in conditions of both low and very low exposure to the toxicant, so for the analysis of occupational exposure to benzene it is best to recommend abstention from smoking at least in the hours immediately before urine collection.
Giornale italiano di medicina del lavoro ed ergonomia 04/2011; 33(2):117-24.
[Show abstract][Hide abstract] ABSTRACT: To verify whether urinary benzene is an applicable biomarker of occupational exposure to very low concentrations of benzene, considering the influence of cigarette smoke and benzene-toluene co-exposure.
23 filling station attendants with occupational exposure to benzene and 31 controls were analyzed. Occupational and environmental exposure was monitored and t,t-muconic acid (t,t-MA), S-phenylmercapturic acid (SPMA), urinary benzene and creatinine in the urine samples were tested.
Occupational exposure to benzene and toluene was significantly higher in the filling station attendants than in the controls, whereas t,t-MA, SPMA and urinary benzene were not different in the two groups. Instead, the smoker group showed significantly higher values for the above biomarkers than the non-smoker group, each of which included both exposed workers and controls. SPMA was dependent on airborne benzene and cigarette smoking, and urinary benzene only on cigarette smoking, while t,t-MA was not dependent on either of these variables.
At very low concentrations of occupational exposure to benzene, urinary benzene is less valid than SPMA as a biomarker, even if both are strongly influenced by smoking habit. Abstention from smoking should therefore be recommended for at least two hours before urine collection.
Giornale italiano di medicina del lavoro ed ergonomia 01/2011; 33(1):41-6.
[Show abstract][Hide abstract] ABSTRACT: The present study compared three methods for the determination of S-phenylmercapturic acid (S-PMA), a metabolite of benzene, in human urine: a HPLC/MS/MS technique with two different sample treatments (strong and partial hydrolysis) and a commercial assay based on anti-S-PMA monoclonal antibodies with chemiluminescence detection. Biological monitoring was done on 126 volunteers and the results were compared for the three methods and also with benzene exposure levels (range <3.0-592.5 μg/m(3)). The correlation between environmental monitoring data and S-PMA levels in non-smokers (n=73) was highly significant (p<0.0001, Student's t-test) for both HPLC/MS/MS methods (r=0.65 both for strong acidic hydrolysis of the urine and hydrolysis at pH 2) but not for the immunoassay, which overestimated the S-PMA levels by about 8 μg/g creatinine (creat.). Therefore the immunoassay is only useful as a semiquantitative screening test, but quantitative results need to be confirmed by a more accurate method like HPLC/MS/MS. The HPLC/MS/MS procedure with strong acid hydrolysis led to a recovery of S-PMA about double that using pH 2 hydrolysis, giving more accurate results. The difference between the results with the two methods makes it difficult to compare the strong acidic hydrolysis data with the ACGIH BEI value of 25 μg/g creat. since the BEI(®) documentation is based on data collected in pH conditions that were not always controlled, which may underestimate the true S-PMA concentration. Besides, as levels of benzene exposure were high, smoking was not considered a confounding factor. The BEI for S-PMA in end of shift urine samples could be reconsidered when sufficient data are available from studies where the analyses are carried out in comparable conditions of hydrolysis and monitoring only non-smoking subjects.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 11/2009; 878(27):2529-33. DOI:10.1016/j.jchromb.2009.11.011 · 2.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: New linear and cyclic guanidines were synthesized and tested in vitro for their antifungal activity toward clinically relevant strains of Candida species, in comparison to fluconazole. Macrocyclic compounds showed a minimum inhibitory concentration in the micromolar range and a biological activity profile in some cases better than that of fluconazole. One macrocyclic derivative was also tested against Aspergillus species and showed high antifungal activity comparable to that of amphotericin B and itraconazole.
[Show abstract][Hide abstract] ABSTRACT: This study was aimed to identify useful biomarkers of exposure and effect in workers exposed to low levels of benzene, and to evaluate any correlations existing between these parameters. Benzene exposure was measured in 33 petrochemical industry operators (PIO), 28 service station attendants (SSA), 21 gasoline pump maintenance workers (GPMW) and 51 non-exposed controls by GC-FID analysis. Samples were collected with personal passive samplers (Radiello). End-shift urine samples were collected for t,t-muconic acid (t,t-MA) determination by HPLC and for S-phenylmercapturic acid (S-PMA) measurement by HPLC-MS/MS. The alkaline version of the comet assay and, in a subgroup of 19 SSA and 16 control subjects, chromosomal aberrations (CA) and glutathione (GSH) levels were measured in peripheral blood lymphocytes. Personal benzene exposure was significantly higher in PIO, SSA and GPMW as compared to controls. The urinary excretion of the two metabolites showed a significant increase in SSA (p=0.0258 and p=0.0001, for t,t-MA and S-PMA, respectively) and in PIO (p=0.0013 and p=0.0001, for t,t-MA and S-PMA, respectively) as compared with the control group, while no such increase was observed for GPMW, for whom occupational exposure was not continuous and occurred on specific working days only. Significant increases of DNA damage were found by the comet assay for tail moment (TM) and tail length (TL) in SSA (p<0.0001 and p=0.008, for TM and TL, respectively) and PIO (p<0.0001 and p<0.0001, for TM and TL, respectively) when compared with controls. The PIO group also displayed a significant increase in the number of cells with comet (p<0.0001). Smoking habits did not appear to interfere with these results in any of the groups. No difference was found in percentage of CA between exposed workers and controls. Significant correlations were found, in all groups, between benzene exposure and the more representative comet parameter TM (r=0.509, p=0.007; r=0.525, p=0.017 and r=0.420, p=0.046 in SSA, GPMW, and PIO, respectively). A trend of negative correlation was observed between DNA damage and either GSH or urine S-PMA for exposed workers. In summary, in present study urinary S-PMA and DNA damage by the comet assay were both sensitive to exposure to low levels of benzene, and GSH seems to play an important defence role against benzene-dependent DNA damage.
[Show abstract][Hide abstract] ABSTRACT: ObjectivesThis study analyzes the validity of new, more sensitive and specific urinary biomarkers of internal dose, namely, urinary
benzene for benzene and urinary toluene and S-benzylmercapturic acid (SBMA) for toluene, to assess their efficacy when compared to traditional biomarkers for biological
monitoring of occupational exposure to low concentrations of these two toxic substances.
MethodsAssessment was made of 41 workers occupationally exposed to benzene and toluene, 18 fuel tanker drivers and 23 filling-station
attendants, as well as 31 subjects with no occupational exposure to these toxic substances (controls). Exposure to airborne
benzene and toluene was measured using passive Radiello® personal samplers worn throughout the work shift. In urine samples collected from all subjects at the end of the workday,
both the traditional and the new internal dose biomarkers of benzene and toluene were assessed, as well as creatinine so as
to apply suitable adjustments.
ResultsOccupational exposure to benzene and toluene resulted significantly higher in the fuel tanker drivers than the filling-station
attendants, and higher in the latter than in controls. Significantly higher concentrations of t,t-muconic acid (t,t-MA), S-phenylmercapturic acid (SPMA), urinary benzene, SBMA and urinary toluene were found in the drivers than the filling-station
attendants or the controls. Instead, urinary phenol and hippuric acid were not different in the three groups. In the entire
sample, airborne benzene and toluene values were significantly correlated, as were the respective urinary biomarkers, showing
coefficients ranging from 0.36 to 0.98. Subdividing the subjects by smoking habit, higher coefficients were evident in non-smokers
than in smokers; at multiple regression analysis t,t-MA, SPMA and urinary benzene and toluene were dependent on the number of cigarettes smoked daily and on airborne benzene
and toluene, respectively. Instead, SBMA was dependent only on airborne toluene.
ConclusionsOur research confirmed the validity of t,t-MA and SPMA for use in the biological monitoring of exposure to low concentrations of benzene. Urinary benzene showed comparable
validity to SPMA; both parameters are affected by smoking cigarettes in the hours before urine collection, so it is best to
ask subjects to refrain from smoking for 2h before urine collection. Urinary toluene was found to be a more specific biomarker
International Archives of Occupational and Environmental Health 03/2009; 83(3):341-356. DOI:10.1007/s00420-009-0469-7 · 2.20 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Occupational exposure to styrene was studied in 34 workers employed in the production of fiberglass-reinforced plastic sheets and compared to 29 unexposed healthy controls. We evaluated genotoxic effects induced by occupational styrene exposure in lymphocytes by alkaline version of the comet assay to detect single-strand breaks (SSBs), DNA oxidation products (formamido pyrimidine glycosilase (Fpg)- and endonuclease (Endo III)-sensitive sites) and DNA repair kinetics studies, as well as the neutral version of comet assay for DNA double-strand breaks (DSBs). An innovative aspect of this study was the use of immuno-comet assay, a new technique that recognizes DSBs with specific antibody by DAPI/FITC method. The battery of parameters included markers of external and internal exposure. Exposed workers showed significant high levels of SSBs (p<0.0001) and DSBs (p<0.0001) in neutral- and immuno-comet assay. A drastic decrease in DNA repair activity as compared to controls was observed (180 min vs. 35 min). Styrene workplace concentration significantly correlated with alkaline comet parameters (TM, p=0.013; TI, p=0.008), in negative with TL (p=0.022), and with DNA-base oxidation (TM Endo III, p=0.048 and TI Endo III, p=0.028). There was a significant negative correlation between urinary metabolites (MA+PGA) and TM Endo III (p=0.032) and TI Endo III (p=0.017).
[Show abstract][Hide abstract] ABSTRACT: The comet assay has been widely used to quantify DNA damage in isolated lymphocytes from subjects exposed to several environmental or occupational substances, especially for estimation of oxidative damage in the DNA, which is well-known to be induced by tobacco smoke. Passive smoking or environmental tobacco smoke (ETS) has been included among those substances that cause cancer with sufficient evidence in humans. In this study, we analyzed, by the alkaline version of comet assay, the lymphocyte DNA damage of white-collar active smokers and non- and ex-smokers exposed to ETS at the workplace. We investigated basal DNA damage, DNA oxidation by formamidopyrimidine glycosylase (Fpg), the repair capacity H2O2-induced DNA damage by kinetics studies and lymphocyte GSH levels, the major intracellular defense against exogenous oxidative stress imposed by cigarette smoking. Our results indicated high basal DNA damage with clear significant correlations with urinary nicotine and cotinine, number of cigarettes/day, and an inverse significant correlation with GSH cellular content in active smokers. Significant Fpg-sensitive sites were found in smokers (> 85%), considerably high but not significant in passive non- and ex-smokers (> 51% and 37%, respectively). The DNA repair capacity had seriously decreased in non-smokers > smokers > ex-smokers, while the same damage was repaired in a short time in never smokers.
[Show abstract][Hide abstract] ABSTRACT: In this study we evaluated the clinical usefulness of identifying urothelial cells with increased DNA damage with the alkaline comet assay and compare it with voided urine cytology for the assessment of markers indicative of bladder cancer. The analysis was carried out on 105 subjects having clinical suspicion of bladder cancer, and who had undergone cytology for the first time. Urine cytology and alkaline comet assay were performed on the same fresh urine samples obtained from each patient. The subjects were divided according to negative or positive cytology. The Mann-Whitney U-test showed that the comet parameters (tail moment, tail length, and % of DNA in the tail) and the numbers of comets (cells with an arbitrary cut-off value of head intensity <90% of DNA content) in subjects positive in both tests were significantly higher than in the negative group. Sensitivity, specificity, and positive and negative predictive value of the comet assay were compared with those of cytology, which is regarded as the gold standard. Sensitivity was 71.4%, specificity was 91.8%, positive and negative predictive values were 38.5 and 97.8, respectively. Two subjects negative in the comet assay were positive in cytology. Eight patients were positive in the comet assay and negative for cytology. Interestingly, one of these eight patients was later found positive for cytology. Logistic regression analysis indicates that the tail moment is significantly associated with an increased risk for positive cytology.
Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis 11/2004; 564(1):57-64. DOI:10.1016/j.mrgentox.2004.07.010 · 3.68 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Despite recognition of the devastating malignant potential of the pancreatic ductal cancer, the exact pathophysiological events contributing to tumor growth remain to be elucidated. Expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 were found to be frequently elevated in several types of human cancer and have also been directly linked to carcinogenesis. The purpose of this study was to determine the expression of COX-1, COX-2 and iNOS in human pancreatic cancer and matched normal adjacent tissue by the Western blot assay. Marked COX-2 expression was observed in cancer tissue compared with the normal surrounding tissue. The iNOS protein was markedly expressed only in pancreatic cancer while the expression of COX-1 was similar in both normal and cancerous tissue. Our findings indicate that COX-2 up-regulation and the expression of iNOS in pancreatic cancer, not seen in normal tissue, may play a role in the pathogenesis of human pancreatic adenocarcinomas. These observations suggest that COX-2 and iNOS may be a target for prevention or treatment of pancreatic carcinomas.
[Show abstract][Hide abstract] ABSTRACT: Objective: Since nitric oxide (NO) plays an important role in regulating vascular tone and changes in the plasma concentration of the end product of NO (nitrite/nitrate) have been observed during exercise, we studied the influence of acute exercise on nitrite/nitrate plasma levels in a group of semiprofessional football players and in younger and older sedentary subjects. Methods: The subjects exercised for 10 min on a cycle ergometer and blood samples were obtained at rest and immediately after exercise. Plasma samples were analysed for nitrite/nitrate. Results: The acute physical exercise induced a significant increase in nitrite/nitrate plasma levels both in sedentary and in active subjects. No difference was evident between the younger and older subjects, both in the basal level and after exercise, indicating that the changes could not be due to age. The higher basal plasma level of nitrite/nitrate observed in the active subjects compared with sedentary groups indicates that the state of physical conditioning had an effect on resting NO concentration. Conclusion: It seems that either acute exercise, even for a short time, or training can induce an increase in circulating NO.
Medical Principles and Practice 07/2001; 10(2):106-109. DOI:10.1159/000050351 · 1.34 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Objective: This study was designed to investigate the role of endogenous nitric oxide (NO) and prostaglandin E2 (PGE2) in the gastroprotection induced by lipopolysaccharide (LPS). Methods: Ethanol was used to induce gastric lesions in control rats and in rats pretreated with graded doses of LPS administered at different time intervals and with inhibitors of NO synthase or prostaglandin synthesis. The ethanol-induced damage on gastric mucosa was assessed by measuring the extent of the lesion. We evaluated nitrite, a breakdown of NO, and PGE2 accumulation in ex vivo gastric mucosa. Results: The ex vivo production of both NO and PGE2 was increased in a dose-dependent manner by LPS injected 5 h before ethanol. Pretreatment with L-N6-(1-iminoethyl)lysine(dihydrochloride) inhibited the protection associated with LPS and the ex vivo increase of both NO and PGE2. Indomethacin was ineffective in suppressing LPS-mediated protection against ethanol-induced damage and in suppressing ex vivo increase of nitrite whereas the ex vivo increase of PGE2 was prevented in a dose-dependent manner. When ethanol was administered 30 min after LPS, there was a lack of protection and a lack of increase of NO and PGE2. Conclusion: These results indicate that the reduction in ethanol-mediated damage in LPS-treated rats depends on endogenous PGE2 formation and on endogenous NO produced by stimulation of inducible NO synthase.
Medical Principles and Practice 01/2001; 10(3):140-144. DOI:10.1159/000050358 · 1.34 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: For a better understanding of the regulation of prostaglandin and nitric oxide (NO) synthesis in circumstances in which the gastric mucosa is inflamed, we have examined the ex vivo production of NO and prostaglandin E2 and the protein expression of inducible nitric oxide synthase (iNOS) and 2 cyclo-oxygenase (COX) isoforms in gastric biopsies from nine Helicobacter pylori-infected patients with active gastritis and six Helicobacter pylori (HP)-negative patients. The results indicate a significant increased of NO and PGE2 in patients with HP infection compared with uninfected samples. These findings were paralleled by marked increases in iNOS and in COX-1 and COX-2 protein expression. Expression of iNOS and COX-2 protein was absent in the mucosa of HP-negative controls. We have demonstrated that iNOS protein is expressed in the gastric mucosa of patients with HP infection. It is likely that iNOS expression and the corresponding high release of NO may play an important role in gastric inflammation associated with HP infection. However, the expression of COX-1 and COX-2 and the parallel increase of prostaglandin E2 could imply that these factors could limit the extend of mucosal damage. In previous reports NO has been shown to stimulate the COX activity, so we think that the role of NO could be both in the regulation of normal function and in the genesis of diseases.
[Show abstract][Hide abstract] ABSTRACT: The interaction between endogenous nitric oxide (NO), elicited by administration of Escherichia coli lipopolysaccharide, and cyclooxygenase system, in ethanol-induced injury in rat gastric mucosa, was investigated. Administration of graded doses of lipopolysaccharide reduced the gastric mucosal injury in response to ethanol. The ex vivo production of both nitrite and prostaglandin E2 was increased in dose-related manner by lipopolysaccharide. Pretreatment with dexamethasone, L-N6-(1-Iminoethyl)lysine(dihydrochloride) and L-NG-nitro arginine methyl ester inhibited the protection associated with lipopolysaccharide treatment and the ex vivo production of both, nitrite and prostaglandin E2. The pretreatment with L-arginine counteracted the decrease of nitrite and prostaglandin E2 production in lipopolysaccharide-treated rats in which nitric oxide synthesis was blocked by L-N6-(1-Iminoethyl)lysine(dihydrochloride). Administration of sodium nitroprusside and S-nitroso-N-acetyl-D,L-penicillamine caused a dose related enhancement in the accumulation of prostaglandin E2. Indomethacin administration and N-(2-Cyclohexyloxy-4-nitrophenyl)methanesulfonamide were ineffective in suppressing lipopolysaccharide-mediated protection against ethanol-induced damage, and in suppressing ex vivo increase of nitrite whereas the ex vivo increase of prostaglandin E2 was prevented in a dose-related fashion. These results indicate that in ethanol-induced rat gastric injury, endogenous NO elicited by lipopolysaccharide or released by NO donors is able to activate the cyclooxygenase pathway, and the protective effect of lipopolysaccharide is dependent upon NO formation.
European Journal of Pharmacology 06/1998; 348(2-3):247-56. DOI:10.1016/S0014-2999(98)00161-7 · 2.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This study was designed to determine the effects of oral administration of the copper(II) complex of amino acids, on gastric lesions induced by ethanol in rats and the possible mechanism(s) of protection. The copper(II) complex of L-tryptophan and L-phenylalanine is reported as the most effective in reducing ulcer numbers as well as ulcer severity of the many amino acid complexes studied. We investigated the role of PGE2 and nitric oxide (NO) in the protection afforded by Cu(II)(L-Trp)(L-Phe) against ethanol-induced damage. The involvement of endogenous eicosanoids and NO was evaluated with the respective inhibitors of prostaglandin and NO synthesis, indomethacin and NG-nitro-L-arginine (L-NNA). Ex vivo PGE2 accumulation in the rat gastric mucosa has also been determined. Pretreatment with indomethacin only partially counteracted the protective activity of Cu(II)(L-Trp)(L-Phe). L-NNA did not attenuate the protection by Cu(II)(L-Trp)(L-Phe), which was reduced but not prevented by indomethacin, suggesting that prostanoids contribute to the Cu(II)(L-Trp)(L-Phe) protective effect, together with some mechanism(s) other than NO synthesis.
Pharmacological Research 12/1997; 36(5):395-9. DOI:10.1006/phrs.1997.0247 · 4.41 Impact Factor