Quantification of three DNA Lesions by Mass Spectrometry and Assessment of Their Levels in Tissues of Mice Exposed to Ambient Fine Particulate Matter.

DNA adducts and oxidized DNA bases are examples of DNA lesions that are useful biomarkers for the toxicity assessment of substances that are electrophilic, generate reactive electrophiles upon biotransformation, or induce oxidative stress. Among the oxidized nucleobases, the most studied one is 8-oxo-7,8-dihydroguanine (8-oxoGua) or 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo), a biomarker of oxidatively induced base damage in DNA. Aldehydes and epoxyaldehydes resulting from the lipid peroxidation process are electrophilic molecules able to form mutagenic exocyclic DNA adducts, such as the etheno adducts 1,N-etheno-2'-deoxyguanosine (1,N-εdGuo) and 1,N-etheno-2'-deoxyadenosine (1,N-εdAdo), which have been suggested as potential biomarkers in the pathophysiology of inflammation.

Genotoxic and epigenotoxic effects in mice exposed to concentrated ambient fine particulate matter (PM) from São Paulo city, Brazil.

Background: The Metropolitan Area of São Paulo has a unique composition of atmospheric pollutants, and positive correlations between exposure and the risk of diseases and mortality have been observed. Here we assessed the effects of ambient fine particulate matter (PM) on genotoxic and global DNA methylation and hydroxymethylation changes, as well as the activities of antioxidant enzymes, in tissues of AJ mice exposed whole body to ambient air enriched in PM, which was concentrated in a chamber near an avenue of intense traffic in São Paulo City, Brazil.

Results: Mice exposed to concentrated ambient PM (1 h daily, 3 months) were compared to in situ ambient air exposed mice as the study control.

Longitudinal study of lung function in pregnant women: Influence of parity and smoking.

Objectives: To evaluate pulmonary function in the first and third trimesters of pregnancy and analyze the influence of parity and smoking on spirometry parameters.

Methods: This longitudinal prospective study included a cohort of 120 pregnant women. The inclusion criteria were as follows: singleton pregnancy, gestational age less than 13.

Urban air pollutants are significant risk factors for asthma and pneumonia in children: the influence of location on the measurement of pollutants.

Background: Air pollution is associated with a substantial burden on human health; however, the most important pollutants may vary with location. Proper monitoring is necessary to determine the effect of these pollutants on respiratory health.

Objectives: This study was designed to evaluate the role of outdoor, indoor and personal exposure to combustion-related pollutants NO(2) and O(3) on respiratory health of children in a non-affluent urban area of São Paulo, Brazil.

Endothelial dysfunction in the pulmonary artery induced by concentrated fine particulate matter exposure is associated with local but not systemic inflammation.

Clinical evidence has identified the pulmonary circulation as an important target of air pollution. It was previously demonstrated that in vitro exposure to fine particulate matter (aerodynamic diameter≤2.5 μm, PM2.

Cardiac and pulmonary oxidative stress in rats exposed to realistic emissions of source aerosols.

In vivo chemiluminescence (CL) is a measure of reactive oxygen species in tissues. CL was used to assess pulmonary and cardiac responses to inhaled aerosols derived from aged emissions of three coal-fired power plants in the USA. Sprague-Dawley rats were exposed to either filtered air or: (1) primary emissions (P); (2) ozone oxidized emissions (PO); (3) oxidized emissions + secondary organic aerosol (SOA) (POS); (4) neutralized oxidized emissions + SOA (PONS); and (5) control scenarios: oxidized emissions + SOA in the absence of primary particles (OS), oxidized emissions alone (O), and SOA alone (S).

Urban, traffic- related particles and lung tumors in urethane treated mice.

Objective: The present study was designed to evaluate the effects of urban, traffic-related, fine particulate matter (PM2.5) on mice lung tumorigenesis under controlled exposure conditions.

Methods: Four groups of female Swiss mice were treated with intraperitonial injections of urethane and saline solution.

Toxicological evaluation of realistic emission source aerosols (TERESA)--power plant studies: assessment of breathing pattern.

Our approach to study multi-pollutant aerosols isolates a single emissions source, evaluates the toxicity of primary and secondary particles derived from this source, and simulates chemical reactions that occur in the atmosphere after emission. Three U.S.

Toxicological evaluation of realistic emission source aerosols (TERESA)-power plant studies: assessment of cellular responses.

The Toxicological Evaluation of Realistic Emission Source Aerosols (TERESA) project assessed primary and secondary particulate by simulating the chemical reactions that a plume from a source might undergo during atmospheric transport and added other atmospheric constituents that might interact with it. Three coal-fired power plants with different coal and different emission controls were used. Male Sprague-Dawley rats were exposed for 6 h to either filtered air or aged aerosol from the power plant.

Composition of diesel particles influences acute pulmonary toxicity: an experimental study in mice.

Ambient particles have been consistently associated with adverse health effects, yielding mainly high cardiorespiratory morbidity and mortality. Diesel engines represent a major source of particles in the urban scenario. We aimed to modify the composition of diesel particles, by means of different extraction procedures, to relate changes in chemical profile to corresponding indicators of respiratory toxicity.

Chronic exposure to urban air pollution induces structural alterations in murine pulmonary and coronary arteries.

Epidemiological studies have shown that air pollution increases cardiovascular morbidity and mortality. Objective markers of cardiovascular risk have also been associated with increases in ambient pollution. This study was designed to assess whether prolonged exposure to ambient levels of air pollution may induce structural alterations of pulmonary and cardiac vessels.

Homozygous deletion of p16INK4a and tobacco carcinogen exposure in nonsmall cell lung cancer.

Inactivation of p16(INK4a) in the Rb pathway is among the most common somatic alterations observed in nonsmall cell lung cancers (NSCLCs). While epigenetic inactivation of the p16(INK4a) gene promoter has been shown to be associated with increased tobacco carcinogen exposure, little investigation of any similar association of homozygous deletion or mutation of p16(INK4a) and tobacco use has been completed. In 177 consecutive NSCLCs, we examined the determinants of p16(INK4a) homozygous deletion and mutation, including the pattern of tobacco smoking and asbestos exposure.

Distribution of collagen in the lamina propria of the human vocal fold.

Objectives: To describe the arrangement of collagen fibers in the lamina propria of the human vocal fold.

Study Design: Analysis of the lamina propria of the vocal fold obtained from human cadavers.

Methods: The Picrosirius-polarization method was used to visualize collagen fibers.