Online two-dimensional liquid chromatography can be used under various separation modes but is sometimes limited in terms of orthogonality, especially for the analysis of neutral compounds. The use of SFC in the second dimension offers a wide choice of mobile and stationary phases, suggesting retention properties complementary to those of the first dimension. Initial works on online LCxSFC coupling published in the literature highlighted the first difficulties of solvent compatibility or potential problems with bubbles created by CO in loops.
View Article and Find Full Text PDFSynthetic complex esters and polyol esters are incorporated as partially bio-based and biodegradable alternatives to petroleum base oils in lubricant formulations, to provide specific properties or performance and to help reducing their carbon footprint in certain cases. A sample can contain over 400 molecules of high chemical similarity including numerous isomers. To resolve such complexity, a separation technique with large peak capacity coupled to high-resolution mass spectrometry (HRMS) is essential.
View Article and Find Full Text PDFObjective: Air pollution is a leading preventable risk factor for cardiovascular diseases. Previous studies mostly relied on concentrations at residence, which might not represent personal exposure. Personal air pollution exposure has a greater variability compared with levels of ambient air pollution, facilitating evaluation of exposure-response functions and vascular pathophysiology.
View Article and Find Full Text PDFBackground: Land-use changes in city fringes due to urbanization can lead to a reduction of greenspace that may reduce its associated health benefits.
Objectives: We evaluated the association between changes in residential surrounding built-up land use and cardiometabolic risk factors in an urbanizing peri-urban area of south India and explored the mediating roles of air pollution, physical activity, and stress in these associations.
Methods: We analyzed data on 6,039 adults from the third follow-up of the Andhra Pradesh Children and Parent Study (APCAPS) cohort (2010-2012).
Background: Evidences that oxidative stress plays a role in the associations between outdoor air pollution and asthma are growing. We aimed to study the role of plasma fluorescent oxidation products levels (FlOPs; an oxidative stress-related biomarker), as potential mediators, in the associations between outdoor air pollution and persistent asthma.
Methods: Analyses were conducted in 204 adult asthmatics followed up in the French case-control and family study on asthma (EGEA; the Epidemiological study of the Genetic and Environmental factors of Asthma).
Background: While uncontrolled asthma in adults is frequent in Europe, the impact of socioeconomic position (SEP) was little investigated. We aimed to investigate the respective association of individual- and area-level SEP with uncontrolled asthma among French elderly women.
Methods: Analyses were conducted in the Asthma-E3N study, among participants with current asthma (i.
Background: Evidence linking ambient air pollution with atherosclerosis is lacking from low- and middle-income countries. Additionally, evidence regarding the association between household air pollution and atherosclerosis is limited. We evaluated the association between ambient fine particulate matter [particulate matter with an aerodynamic diameter of ≤2.
View Article and Find Full Text PDFBackground: Limited evidence exists on the effect of particulate air pollution on blood glucose levels. We evaluated the associations of residential and personal levels of fine particulate matter (PM) and black carbon (BC) with blood glucose and diabetic status among residents of 28 peri-urban villages in South India.
Methods: We used cross-sectional data from 5065 adults (≥18 years, 54% men) included in the Andhra Pradesh Children and Parents Study.
Scalable exposure assessment approaches that capture personal exposure to particles for purposes of epidemiology are currently limited, but valuable, particularly in low-/middle-income countries where sources of personal exposure are often distinct from those of ambient concentrations. We measured 2 × 24-h integrated personal exposure to PM and black carbon in two seasons in 402 participants living in peri-urban South India. Means (sd) of PM personal exposure were 55.
View Article and Find Full Text PDFBackground: Evidence linking long-term exposure to particulate air pollution to blood pressure (BP) in high-income countries may not be transportable to low- and middle-income countries. We examined cross-sectional associations between ambient fine particulate matter (PM2.5) and black carbon (BC) with BP (systolic [SBP] and diastolic [DBP]) and prevalent hypertension in adults from 28 peri-urban villages near Hyderabad, India.
View Article and Find Full Text PDFBackground: The gender switch in asthma incidence around puberty has been put forward to suggest a role of sex hormones in asthma. However, there are limited and inconsistent findings on change in asthma incidence with menopause. We aimed to investigate the associations between menopause and asthma incidence, and interactions with overweight/obesity.
View Article and Find Full Text PDFEvidence identifying factors that influence personal exposure to air pollutants in low- and middle-income countries is scarce. Our objective was to identify the relative contribution of the time of the day ( when?), location ( where?), and individuals' activities ( what?) to PM personal exposure in periurban South India. We conducted a panel study in which 50 participants were monitored in up to six 24-h sessions ( n = 227).
View Article and Find Full Text PDFData regarding which microenvironments drive exposure to air pollution in low and middle income countries are scarce. Our objective was to identify sources of time-resolved personal PM exposure in peri-urban India using wearable camera-derived microenvironmental information. We conducted a panel study with up to 6 repeated non-consecutive 24 h measurements on 45 participants (186 participant-days).
View Article and Find Full Text PDFLand-use regression (LUR) has been used to model local spatial variability of particulate matter in cities of high-income countries. Performance of LUR models is unknown in less urbanized areas of low-/middle-income countries (LMICs) experiencing complex sources of ambient air pollution and which typically have limited land use data. To address these concerns, we developed LUR models using satellite imagery (e.
View Article and Find Full Text PDFAssociations between outdoor air pollution and asthma in adults are still scarce, and the underlying biological mechanisms are poorly understood. Our aim was to study the associations between 1) long-term exposure to outdoor air pollution and current asthma, 2) exhaled 8-isoprostane (8-iso; a biomarker related to oxidative stress) and current asthma, and 3) outdoor air pollution and exhaled 8-iso.Cross-sectional analyses were conducted in 608 adults (39% with current asthma) from the first follow-up of the French case-control and family study on asthma (EGEA; the Epidemiological study of the Genetic and Environmental factors of Asthma).
View Article and Find Full Text PDFMultimedication related to multimorbidity is common in the elderly with asthma. We aimed at comprehensively characterising medications used by elderly women and assessing how multimedication impacts on asthma prognosis.We performed network-based analyses on drug administrative databases to visualise the prevalence of drug classes and their interconnections among 17 458 elderly women from the Asthma-E3N study, including 4328 women with asthma.
View Article and Find Full Text PDFBackground: Despite the increasing interest in place effect to explain health inequalities, there is currently no consensus on which kind of area-based socioeconomic measures researchers should use to assess neighborhood socioeconomic position (SEP). The study aimed to evaluate the reliability of different area-based deprivation indices (DIs) in capturing socioeconomic residential conditions of French elderly women cohort.
Methods: We assessed area-based SEP using 3 DIs: Townsend Index, French European Deprivation Index (FEDI) and French Deprivation index (FDep), among women from E3N (Etude épidémiologique auprès des femmes de la Mutuelle Générale de l'Education Nationale).
Background: With population aging, further asthma research is needed in the elderly.
Objective: We assessed the relevance of the controller-to-total asthma medication ratio and its fluctuations over time to identify participants with a subsequent risk of poor asthma-related outcomes among well-characterized elderly women.
Methods: We studied 4,328 women with ever asthma (69.
Int J Environ Res Public Health
July 2017
Daily mobility, an important aspect of environmental exposures and health behavior, has mainly been investigated in high-income countries. We aimed to identify the main dimensions of mobility and investigate their individual, contextual, and external predictors among men and women living in a peri-urban area of South India. We used 192 global positioning system (GPS)-recorded mobility tracks from 47 participants (24 women, 23 men) from the Cardiovascular Health effects of Air pollution in Telangana, India (CHAI) project (mean: 4.
View Article and Find Full Text PDFWhile there is convincing evidence that fine particulate matter causes cardiovascular mortality and morbidity, little of the evidence is based on populations outside of high income countries, leaving large uncertainties at high exposures. India is an attractive setting for investigating the cardiovascular risk of particles across a wide concentration range, including concentrations for which there is the largest uncertainty in the exposure-response relationship. CHAI is a European Research Council funded project that investigates the relationship between particulate air pollution from outdoor and household sources with markers of atherosclerosis, an important cardiovascular pathology.
View Article and Find Full Text PDFThe role of obesity in adult asthma is well-known and has been partly attributed to a confounding role of physical inactivity. However, the interrelationships between obesity, physical activity, and asthma have been incompletely addressed, probably because their time-dependent and bidirectional nature represents a methodologically challenging research question. We aimed to estimate the independent causal effects of body mass index (BMI; weight (kg)/height (m)2) and physical activity on current asthma using marginal structural models (MSMs).
View Article and Find Full Text PDFBackground: Inconsistent associations between socioeconomic position (SEP) and outdoor air pollution have been reported in Europe, but methodological differences prevent any direct between-study comparison.
Objectives: Assess and compare the association between SEP and outdoor nitrogen dioxide (NO) exposure as a marker of traffic exhaust, in 16 cities from eight Western European countries.
Methods: Three SEP indicators, two defined at individual-level (education and occupation) and one at neighborhood-level (unemployment rate) were assessed in three European multicenter cohorts.
Background: Principal component analysis (PCA) has been used extensively to derive dietary patterns. We proposed to use confirmatory factor analysis (CFA) in the same context as PCA--as a one-step approach--to derive dietary patterns.
Objectives: The first aim of this study was methodologic and was to compare dietary patterns derived with the use of PCA and CFA, used as equivalent one-step approaches.