Exposure to priority organochlorine contaminants in the Italian general population. Part 2: Fifteen priority polychlorinated biphenyl congeners in blood serum.

Concentrations of 36 polychlorinated biphenyl (PCB) congeners were measured in serum of 372 Italian residents of general population living in Novafeltria, Pavia, and Milan. Total PCB level differed significantly between these sites (p < 0.0001) with median concentrations of 836.50, 1354.57, and 2062.08 pmol/g lipid, respectively. However, there is no evidence for the difference in distribution of total PCB levels by genders. Total dioxin-like PCBs differed significantly (p < 0.0001) between the sites (median 109.78, 50.88, and 166.99 pmol/g lipid, respectively) and genders of Novafeltria and Pavia (p = 0.011 and 0.009, respectively). PCB 138, 153, 170, and 180 differed significantly between the places of residence (p < 0.0001) with higher values in Milan population. In the overall population, total PCB and PCB 138, 153, 156, 170, and 180 correlated positively with age (correlations range between 0.320 and 0.569, p < 0.0001). In Novafeltria, the correlations ranged between 0.545 and 0.670, and in Pavia, the correlations ranged between 0.516 and 0.666. In Milan, correlations with age range between 0.327 and 0.417 for total PCB and congeners 138, 153, and 180. With an exception of PCB 170, there was no evidence of significant difference in the distribution of most abundant PCB congeners and total PCB across the body mass index categories.

Exposure to priority organochlorine contaminants in the Italian general population. Part 1. Eight priority organochlorinated pesticides in blood serum.

Despite extensive use of organochlorinated pesticides (OCPs) such as dichlorodiphenyltrichloroethane (DDT) in Italy in the 1940s to 1970s, especially for public health control of malaria mosquitoes, information on their exposure levels among the general population is limited. These OCPs can be a source of health risk to human. A total of 137 blood samples were collected from residents of the general population of three Italian towns, Novafeltria, Pavia and Milan, to determine the levels of eight OCPs in blood serum. The concentrations of beta-hexachlorocyclohexane, hexachlorobenzene (HCB), 1,1-dichloro-2-(o-chlorophenyl)-2-(p-chlorophenyl)ethylene, 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE), 1,1-dichloro-2-(o-chlorophenyl)-2-(p-chlorophenyl)ethane, 1,1-dichloro-2,2-bis (4-chlorophenyl)ethane, 1,1,1-trichloro-2-(o-chlorophenyl)-2-(p-chlorophenyl)-ethane and 1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane were measured by gas chromatography-mass spectrometry. Variations in serum concentrations of OCPs with respect to place of residence, gender, age and body mass index (BMI) were evaluated by non-parametric tests. p,p'-DDE and HCB were the most abundant and major contributors of total OCP concentration. Their levels differed significantly between the three towns with a trend Milan > Novafeltria > Pavia (p < 0.0001). Females had significantly higher concentrations of HCB and p,p'-DDE than males in the overall population sample. HCB concentrations were significantly higher in females than in males of Milan (p = 0.029). We observed positive correlations of p,p'-DDE and HCB with age in Novafeltria subjects (r = 0.468, p = 0.004). Total OCP concentrations differed significantly across BMI categories (p = 0.018) in overall population. We have demonstrated a clear pattern of the main OCPs in a fairly large population. Generally, our study provides information on OCPs exposure among the Italian general population and provides indications for further investigations.

Molecular modifications induced by inorganic arsenic in Vicia faba investigated by FTIR, FTNIR spectroscopy and genotoxicity testing.

Exposure to inorganic arsenic (iAs) through drinking water is a major public health concern affecting most countries. Epidemiologic studies showed a significant association between consumption of iAs through drinking water and different types of cancer. However, the exact mechanisms underlying As-induced cancer and other diseases are not yet well understood. The aim of this study is to determine the effects of exposure iAs (20 or 30 mg/L) on Vicia faba seedlings in terms of phytotoxicity, genotoxicity, and spectroscopy by investigation of molecular modifications using infrared (FTIR) and near infrared (FTNIR) spectroscopy. Further, the mitigation effects of a precursor of glutathione (GSH), N-acetylcysteine (NAC), were also assessed. Spectroscopic and genotoxicity analysis demonstrated that specific molecular changes were directly correlated with iAs exposure. Comet assay in Vicia faba showed significant effects at concentrations of 20 and 30 mg/L, depending on the structural changes involving nucleic acids as identified by FTIR and FTNIR spectroscopy. Results of phytotoxicity and micronuclei tests were significant only at higher iAs concentrations (30 mg/L), where an antioxidant effect of NAC was noted. The two spectroscopic techniques demonstrated molecular modifications predominantly associated with chemical interactions of iAs with biomolecules such as nucleic acids, carbohydrates, lipids, and proteins in Vicia faba. Our findings suggest that further studies are required to better understand the mechanisms underlying toxicity produced by different As chemical forms in vegetal and agricultural species.

[Possible use of microRNAs as biomarkers for monitoring of workers exposed to asbestos]. / Possibile impiego di microRNA come biomarcatori nel monitoraggio dei lavoratori professionalmente esposti ad amianto.

Exposure to asbestos is the predominant cause of pleural mesothelioma (PM). The PM is a tumor difficult to diagnose, chemoresistant, and with rising Incidence. The long latency periods and the lack of preventive and therapeutic strategies for the MP, suggest that asbestos will be a social and health issue in the near future. Therefore, this overview focuses on current knowledge of epigenetic alterations and on the key role of microRNAs, small RNAs that negatively regulate gene expression, as biomarkers in PM development. Dysregulated microRNA expression pattern is specific for different cancers, including MP. MicroRNA expression analysis is a promising tool for diagnosis, typing of MP than normal tissue and other lung tumors and monitoring of new therapies. However, a better knowledge of miRNA signatures in PM is still necessary to verify the contribution of specific miRNAs as diagnostic biomarkers, also compared to different asbestos forms, exposure and subject work history.

[Molecular biomarkers in workers and population exposed to inorganic arsenic: preliminary study in vitro]. / Biomarcatori molecolari in lavoratori professionalmente esposti ad arsenico inorganico e nella popolazione generale: studio preliminare in vitro.

The inorganic Arsenic (iAs) is a metalloid widely diffuse in all environmental matrices. The iAs has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer. The microRNAs (miRNAs) are small non coding RNAs that negatively regulate the expression of hundreds of target genes in many key physiological and pathological cell processes, including stress response, differentiation, proliferation, apoptosis and cancer, miRNA expression profiles appear altered in most human cancers and it has been highlighted the potential of miRNA profiling in cancer diagnosis and prognosis. The present study evaluates the effect of iAs exposure on global miRNA expression in Jurkat cells. Treated cells show a reproducible increase in the expression levels of three miRNAs: miR-663, miR-222 and miR-638. This study supports the importance to proceeding in the investigation aimed to the possible application of some miRNAs as biomarkers in the environmental and occupational exposure to iAs.

[Epigenetics and environmental exposure to xenobiotics]. / Epigenetica ed esposizione ambientale a xenobiotici.

Environmental pollution, together with predisposing genetic factors, plays a key role in determining short and long-term adverse effects on human health. In the industrialized countries the identification of etiology related to diseases of environmental origin has then become a research of priority interest. With regard to this, it has been widely demonstrated that different chemical compounds, such as endocrine disruptors, are able to modify the epigenetic characteristics of a human being. According to recent studies, the paradigm "genotype is strongly correlated with a phenotype" is changing in favor of the concept that a phenotype is defined by a "genotype and by an epigenome". Thus, there is a genotype identical for all cells associated to the epigenome that causes changes in gene expression without modifying the nucleotide sequence of the genome, through alterations in DNA methylation, histone modifications and the pathway of small non-coding RNAs. The epigenome is easily affected by different factors, such as aberrations of normal epigenetic processes that can be caused by environmental factors as exposure to xenobiotics, social behavior and nutritional deficiencies. Epigenetic changes are thus a biological response to environmental stress factors and may be transmitted to the offspring. As the elimination of the environmental factor determines the possible reversion of epigenetic modifications, it seems not to play a role in the natural selection process. However, epigenetic aberrations affect gene expression by interfering with the stability and survival of cells and with the inactivation of onco-suppressor genes. Thus, it is of considerable interest to investigate about the possible elements of induction of epigenetic processes in order to implement prevention protocols. Moreover, the gene expression screening through high through-put techniques like microarray, represent a new tool for the identification of new epigenetic indicators in order to monitor the early biological effects on the population exposed to xenobiotics.

[Gene expression and environmental exposure to xenobiotics: overview and applications]. / Espressione genica ed esposizione ambientale a xenobiotici: overview e applicazioni.

Industrial chemicals, pesticides, pharmaceuticals, foods, heavy metals, air pollutants, and naturally occurring substances, are an integral part of our daily lives. Environmental exposure can induce changes in gene regulation associated with human diseases. A new discipline of toxicology is "predictive toxicology" that defines the relationship between the structure and activity of the genome and the adverse biological effects of exogenous agents. Toxicogenomic technologies allow complete assessment of the functional activity of biochemical pathways, and of the structural genetic (sequence) differences among individuals (polymorphisms), that were previously unattainable. Microarray technology provides the means to study multiple pathways and mechanisms at concurrent times. Gene expression is a sensitive indicator of toxicant exposure, disease state, and cellular metabolism and thus represents a way of characterising how cells and organisms adapt to changes in the external environment. The application of these technologies to toxicology can lead us into a new era when genotypes and toxicant-induced genome expression, proteins, and metabolite patterns can be used to screen compounds for hazard identification, to monitor individual exposure to toxicants, to track cellular responses to different doses, to assess mechanisms of action, and to predict individual variability in sensitivity to toxicants and potential ways to improve risk assessment.

Leptospirosis survey in wild rodents living in urban areas of Rome.

The aim of the study was to survey the current extension of the infected brown rats (Rattus norvegicus) living on the site Ripa Grande-San Michele port located in the center of the sity along the accessible right bank of the Tiber river by using a specific molecular technology. The detection of Leptospira, in 11 trapped brown rats, by tube-based Polymerase Chain Reaction (PCR) was performed. The amplified samples were analysed by capillary zone electrophoresis (CZE). Sequence analysis of the amplified DNAs confirmed the specificity of the detection of leptospires. Five out of 11 brown rats exhibited positivity for Leptospira. The survey points out the high rate of leptospiral infection in the brown rats living in the most ancient urban area of Rome.

Use of sulphonated probes for detecting human immunodeficiency virus-1 transcripts by in situ hybridization.

A detailed procedure is described that allows detection of the presence of human immunodeficiency virus-1 (HIV-1) transcripts within both acetone-fixed tissues and peripheral blood mononuclear cells. This assay uses cDNA probes labelled by a non-isotopic procedure that results in the modification of cytosine residues through covalent linkage to a sulphone group. In situ hybridized probe is then detected by an alkaline phosphatase-conjugated antibody specifically directed against the sulphone hapten. This procedure is specific, rapid and safe and can be applied in the research as well as in the clinical pathology settings.

Detection of HIV-1 genome in leukocytes of human colostrum from anti-HIV-1 seropositive mothers.

In order to obtain more information about the presence of HIV-1 in mononuclear cells of colostrum, research was carried out on both the HIV-1 genome in the cellular fraction of colostrum and the viral antibody in cell-free colostrum of eight anti-HIV-1 seropositive asymptomatic mothers. In five cases cell fractions of the colostrum harbored HIV-1 genome by DNA-DNA and DNA-RNA in situ hybridization, whereas viral antibody were detected in all cell-free colostrum specimens. The data confirms the colostrum as a possible route of HIV-1 infection.

Persistence of HIV-1 silent infection in seronegative subjects at high risk.

Twenty regular sexual partners of HIV-1 infected subjects, without detectable human immunodeficiency virus (HIV-1) antibody and positive for HIV-1 genome by in situ hybridization (ISH), were selected and studied longitudinally for 6-36 months to estimate the duration of silent infection. During the follow-up period, 10 showed atypical Western Blot (WB) patterns. Two seronegative partners seroconverted. Rapid progress to AIDS was observed in 7 seropositive subjects.

Production of a nef-specific monoclonal antibody by the use of a synthetic peptide.

Monoclonal antibodies have been generated against a synthetic peptide of the nef protein of human immunodeficiency virus type 1 (HIV-1) in order to further characterize the biochemical and functional nature of this protein and its role in the control of HIV-1 transcriptional regulation. Earlier studies indicated nef to be a negative regulatory factor for viral transcription, whereas more recent studies report evidence against this original hypothesis. Nef is a protein of 206 amino acids of approximately 27 kD in most HIV-1 isolates; however, in some other isolates a truncated form of 124 amino acids has been described. A peptide sequence of six amino acids, corresponding to a region of the nef protein exhibiting high-sequence homology to thymosin alpha 1 protein, has been synthesized by Merrifield solid-phase methodology. This peptide is coded by a sequence located upstream to the stop codon described in some HIV-1 isolates and then is maintained in both complete and truncated forms of the nef protein. F14.11 is a nef peptide-specific monoclonal antibody (IgG2a/k) exhibiting the ability to recognize natural nef protein in either radioimmunoassay, radioimmunoprecipitation assay, or immunocytochemical analysis. Since F14.11 is able to identify nef protein in the cytoplasm of lymphocytes from HIV-infected seronegative subjects it may prove useful in monitoring the expression of nef during the silent HIV-1 infection.

Detection of HIV genome in HIV antibody negative men.

The presence of the human immunodeficiency virus (HIV) genome was investigated by applying in situ hybridisation techniques to peripheral blood mononuclear cells (PBMCs). Twenty asymptomatic anti-HIV seronegative homosexual men were the subjects of our study. The cells were hybridised with: (1) an SP 64 plasmid containing the nine-kilobase SstI-SstI viral insert from the lambda BH 10 recombinant clone; this can recognise both viral RNA and proviral DNA, and (2) with a pA01 plasmid containing HBV DNA genome. The DNA probes were modified by inserting an antigenic sulfone group in the cytosine moieties and the visualisation was performed by a double antibody immunohistochemical reaction. In two subjects both the HIV genome and HBV DNA were detected whereas another two subjects were positive for HBV DNA and for the HIV genome respectively. Thus people who are seronegative for anti-HIV specific antibodies may be infected with HIV.