DAILY FINE AND ULTRAFINE PARTICULATE MATTER EXPOSURE AFFECTS INFLAMMATORY AND COAGULATORY MARKERS AMONG SUSCEPTIBLE SUBJECTS.
Tesi di Dottorato
Data di Pubblicazione:
2011
Citazione:
DAILY FINE AND ULTRAFINE PARTICULATE MATTER EXPOSURE AFFECTS INFLAMMATORY AND COAGULATORY MARKERS AMONG SUSCEPTIBLE SUBJECTS / L. Ruggeri ; tutor: Paolo Carrer ; coordinatore: Giovanni Costa. Universita' degli Studi di Milano, 2011 Jan 27. 23. ciclo, Anno Accademico 2010. [10.13130/ruggeri-laura_phd2011-01-27].
Abstract:
Current concerns about the health effects of airborne particles are largely based on the results of epidemiological studies, suggesting effects on mortality and morbidity for cardiovascular and respiratory causes at very low levels of particulate matter exposure. The mechanisms behind these effects are still unknown, although some hypothesis have been postulated. The studies support the idea that inhalation of PM can instigate extra-pulmonary effects by the release of pro-inflammatory mediators (eg. cytokines, activated immune cells, platelets), vasculoactive molecules (eg. ET, histamine, microparticles) from lung-based cells; and/or by translocation of PM (UFPs) or particle constituents (organic compounds, metals) into the systemic circulation. Subsequently, these events may contribute to a systemic inflammatory state, which may in turn be capable of activating haemostatic pathways, impairing vascular function, and accelerating atherosclerosis.
Which fraction of PM is the most harmful is still controversial, and few studies investigated the role of personal exposure to different fractions, in particular fine and ultrafine particles.
Aims. My doctoral thesis aims at characterize the effects of PM exposure on inflammatory and coagulatory indices in susceptible subjects (with chronic heart diseases or chronic respiratory diseases), focused on the role of the fine and ultrafine particles in determining changes in these markers.
Materials and methods. 27 healthy individuals (Healthy group), 34 individuals with chronic ischemic heart disease (Heart group), 18 with chronic asthma or COPD (Lung group) underwent a 24-hour exposure/clinical evaluation protocol during their habitual activities, both in the warm season (no heating period) and in the cold season (heating period). Individual exposure to UFPs (0.02–1 µm, Aerodynamic Diameter, D.a), fine and coarse particles number concentration (0.3-0.5; 0.5-1.0; 1.0-2.5; 2.5-5.0; 5.0-10 µm D.a), gravimetric PM0.5, PM1, PM2.5 and PM10 was assessed for each subject, along with measurement of total blood cells count and blood markers of inflammation [TNF-alfa, sRI- and sRII-TNF-alfa, IL-8, IL-10, hs-CRP] and coagulation [fibrinogen, aPTT, INR, D-dimer, vWF, tPA, F1+2, closure time measured with PF 100 Analyzer® (PFA100 C-EPI CT e PFA100 C-ADP CT)].
Since the three groups had different clinical status, each group were analyzed independently using mixed effects models for repeated measurements to evaluate the associations between particles exposure and clinical parameters. Models include time varying factor (PM, temperature and relative humidity) and time-invariant subjects specific characteristics (age, gender, BMI, drug assumption). Pollution effects were expressed as percent changes by interquartile range (IQR) changes of PM ( Chuang K. et al. 2007).
Results. The mean age for the overall studied population was 64±10 years at the beginning of the study and the gender was male for the 63% of individuals.
The median (25°-75° percentiles) 24h concentration of PM10 during the no-heating period was 35.5 (29.3-51.1) μg/m3 and during the heating period 58.0 (41.7-79.0) μg/m3. For PM2.5, the median concentration (25°-75° percentiles) during the no-heating period was 26.8 (21.4-37.7) μg/m3 and during the heating period 49.8 (33.7-66.3) μg/m3. Comparing the data from the two monitoring periods, the results showed a significant increase for particulate matter concentrations in the heating ignition power-on period. The PM10 percentage variation was 63.4% and for PM2.5 was 85.8%. The three groups of subjects were exposed to similar PM concentration, except for fine particles (PM0.5, FP0.3-1 D.a), that were higher in the Healthy group.
The subjects in the three groups provided
Tipologia IRIS:
Tesi di dottorato
Keywords:
particulate matter ; individual exposure ; inflammatory markers ; coagulatory markers
Elenco autori:
L. Ruggeri
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