| 1. |
- Gardner, Michael, et al.
(författare)
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Gender and telomere length : Systematic review and meta-analysis
- 2014
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Ingår i: Experimental Gerontology. - : Elsevier. - 0531-5565 .- 1873-6815. ; 51, s. 15-27
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Forskningsöversikt (refereegranskat)abstract
- Background: It is widely believed that females have longer telomeres than males, although results from studies have been contradictory. Methods: We carried out a systematic review and meta-analyses to test the hypothesis that in humans, females have longer telomeres than males and that this association becomes stronger with increasing age. Searches were conducted in EMBASE and MEDLINE (by November 2009) and additional datasets were obtained from study investigators. Eligible observational studies measured telomeres for both females and males of any age, had a minimum sample size of 100 and included participants not part of a diseased group. We calculated summary estimates using random-effects meta-analyses. Heterogeneity between studies was investigated using sub-group analysis and meta-regression. Results: Meta-analyses from 36 cohorts (36,230 participants) showed that on average females had longer telomeres than males (standardised difference in telomere length between females and males 0.090, 95% CI 0.015, 0.166; age-adjusted). There was little evidence that these associations varied by age group (p = 1.00) or cell type (p = 0.29). However, the size of this difference did vary by measurement methods, with only Southern blot but neither real-time PCR nor Flow-FISH showing a significant difference. This difference was not associated with random measurement error. Conclusions: Telomere length is longer in females thanmales, although this difference was not universally found in studies that did not use Southern blot methods. Further research on explanations for the methodological differences is required. (C) 2013 Published by Elsevier Inc.
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| 2. |
- Bongaerts, Eva, et al.
(författare)
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Ambient black carbon particles in human ovarian tissue and follicular fluid
- 2023
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Ingår i: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 179
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Tidskriftsartikel (refereegranskat)abstract
- Evidence indicates a link between exposure to ambient air pollution and decreased female fertility. The ability of air pollution particles to reach human ovarian tissue and follicles containing the oocytes in various maturation stages has not been studied before. Particulate translocation might be an essential step in explaining reproductive toxicity and assessing associated risks. Here, we analysed the presence of ambient black carbon particles in (i) follicular fluid samples collected during ovum pick-up from 20 women who underwent assisted reproductive technology treatment and (ii) adult human ovarian tissue from 5 individuals. Follicular fluid and ovarian tissue samples were screened for the presence of black carbon particles from ambient air pollution using white light generation by carbonaceous particles under femtosecond pulsed laser illumination. We detected black carbon particles in all follicular fluid (n = 20) and ovarian tissue (n = 5) samples. Black carbon particles from ambient air pollution can reach the ovaries and follicular fluid, directly exposing the ovarian reserve and maturing oocytes. Considering the known link between air pollution and decreased fertility, the impact of such exposure on oocyte quality, ovarian ageing and fertility needs to be clarified urgently.
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| 3. |
- Cox, Bianca, et al.
(författare)
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Ambient temperature as a trigger of preterm delivery in a temperate climate
- 2016
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Ingår i: Journal of Epidemiology and Community Health. - : BMJ. - 0143-005X .- 1470-2738. ; 70:12, s. 1191-1199
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Recent evidence suggests that elevated ambient temperatures may trigger preterm delivery. Since results from studies in temperate climates are inconclusive, we investigated the association between temperature and the risk of preterm birth in Flanders (Belgium).METHODS: We used data on 807 835 singleton deliveries (January 1998-July 2011). We combined a quasi-Poisson model with distributed lag non-linear models to allow for delayed and non-linear temperature effects, accounting for the daily pregnancies at risk and their gestational age distribution.RESULTS: For moderate heat (95th vs 50th centile) up to 1 day before delivery (lag 0-1), the risk of preterm birth increased by 8.5% (95% CI 2.4% to 15.0%) when minimum temperature increased from 8.3°C to 16.3°C and by 9.6% (95% CI 1.1% to 18.7%) when maximum temperature increased from 14.7°C to 26.5°C. Corresponding estimates for extreme heat (99th vs 50th centile) were 15.6% (95% CI 4.8% to 27.6%) for minimum temperature (19.0°C vs 8.3°C) and 14.5% (95% CI 0.5% to 30.6%) for maximum temperature (30.7°C vs 14.7°C). Despite the increased risk of preterm birth associated with cold at lag 2 (and lag 1 for minimum temperature), cumulative cold effects were small. The per cent change in preterm birth associated with moderate cold (5th vs 50th centile) up to 3 days before delivery (lag 0-3) was 2.1% (95% CI -4.1% to 8.7%) for minimum temperature (-2.0°C vs 8.3°C) and 0.6% (95% CI -7.3% to 9.2%) for maximum temperature (2.5°C vs 14.7°C).CONCLUSIONS: Even in a temperate climate, ambient temperature may trigger preterm delivery, suggesting that pregnant women should avoid temperature extremes.
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| 4. |
- Delcloo, Andy, et al.
(författare)
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ACCEPTED : An Assessment of Changing Conditions, Environmental Policies, Time-Activities, Exposure and Disease
- 2014
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Ingår i: Air Pollution Modeling and its Application XXIII. - Cham : SPRINGER-VERLAG BERLIN. ; , s. 55-59
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Konferensbidrag (refereegranskat)abstract
- Changes in urban design and traffic policy, demography, climate and associated adaptation, mitigation measures and environmental policies are likely to modify both outdoor and indoor air quality and therefore public health. The project aims to improve our understanding of future exposure situations and their impact on health, from an interdisciplinary approach. This will be achieved by using various state-of-the-art atmospheric models, measurements, epidemiological studies and reviews. To assess population full exposure, an integrated view accounting both for indoor and outdoor air pollution as well as for population time activity data will be developed. New dose-response functions will be estimated between health outcome, air pollution and temperature in order to better estimate the effects on the foetus and young children. Ultimately, scenarios of future urban climate and air quality will be simulated, combining future exposure scenarios, population scenarios and exposure-response functions to describe the effects of different trends and relevant policies on relative risk and burden of illness attributed to urban pollutants and their interactions with extreme temperatures. Also the mitigation strategies that can be used to reduce urbanization and climate change effects on the local urban meteorology and air quality will be assessed. With applications in several large European cities, the project will study the impact of several alternative adaptation scenarios on urban air quality and human health to a mid-century horizon (2030-2060) accounting for the effects of a changing urban climate. Scenario-based health impact assessments will combine exposure information from climate models, emission scenarios, policy evaluation studies and concentration calculations with exposure-response functions from epidemiological studies of vulnerable groups within the project and previously published functions for mortality and hospital admissions. The effects of socioeconomic and demographic trends will be discussed, the predicted health impacts and benefits associated with different interventions and policies and other urban changes will be described.
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| 5. |
- Gouveia-Figueira, Sandra, et al.
(författare)
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Cord blood eicosanoid signatures and newborn gestational age
- 2017
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Ingår i: Prostaglandins & other lipid mediators. - : Elsevier. - 1098-8823 .- 2212-196X. ; 133, s. 123-127
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Tidskriftsartikel (refereegranskat)abstract
- Beyond prostaglandins, the function of eicosanoids and other oxylipins in pregnancy and labor is poorly understood. In contrast to earlier work focusing on preterm infants, we investigated how oxylipin levels in newborns (measured in cord blood) vary during the last weeks of pregnancy in 190 mother-newborns (≥37 weeks of gestation) of the ENVIRONAGE birth cohort, Belgium. We found increased levels of PGE2 (p = 0.003), PGF2α (p = 0.042), 8,9-DHET (p = 0.037), 11-HETE (p = 0.034), and 15-HETrE (p = 0.008) associated with full term pregnancy compared to early term labor. Furthermore, late vs early term was associated with increased levels of PGE2 (p = 0.012) and TXB2 (p = 0.033), while late vs full term was associated with decreased levels of 14,15-DHET (p = 0.029), 11,12-DHET (p = 0.033), and 5-HETE (p = 0.045). To summarize, nine eicosanoids, derived via three enzymatic pathways, were significantly associated with gestational age. Eight of these were derived from arachidonic acid, and one from dihomo-γ-linolenic acid.
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| 6. |
- Lozano, Manuel, et al.
(författare)
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Early life exposure to mercury and relationships with telomere length and mitochondrial DNA content in European children
- 2024
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Ingår i: Science of the Total Environment. - 0048-9697 .- 1879-1026. ; 932
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Tidskriftsartikel (refereegranskat)abstract
- Background: Telomere length (TL) and mitochondrial function expressed as mitochondrial DNA copy number (mtDNAcn) are biomarkers of aging and oxidative stress and inflammation, respectively. Methylmercury (MeHg), a common pollutant in fish, induces oxidative stress. We hypothesized that elevated oxidative stress from exposure to MeHg decreases mtDNAcn and shortens TL. Methods: Study participants are 6–11-year-old children from the HELIX multi-center birth cohort study, comprising six European countries. Prenatal and postnatal total mercury (THg) concentrations were measured in blood samples, TL and mtDNAcn were determined in child DNA. Covariates and confounders were obtained by questionnaires. Robust regression models were run, considering sociodemographic and lifestyle covariates, as well as fish consumption. Sex, ethnicity, and fish consumption interaction models were also run. Results: We found longer TL with higher pre- and postnatal THg blood concentrations, even at low-level THg exposure according to the RfD proposed by the US EPA. The prenatal association showed a significant linear relationship with a 3.46 % increase in TL for each unit increased THg. The postnatal association followed an inverted U-shaped marginal non-linear relationship with 1.38 % an increase in TL for each unit increased THg until reaching a cut-point at 0.96 μg/L blood THg, from which TL attrition was observed. Higher pre- and postnatal blood THg concentrations were consistently related to longer TL among cohorts and no modification effect of fish consumption nor children's sex was observed. No association between THg exposure and mtDNAcn was found. Discussion: We found evidence that THg is associated with TL but the associations seem to be time- and concentration-dependent. Further studies are needed to clarify the mechanism behind the telomere changes of THg and related health effects.
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| 7. |
- Martens, Dries S, et al.
(författare)
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Neonatal Cord Blood Oxylipins and Exposure to Particulate Matter in the Early-Life Environment : an ENVIRONAGE Birth Cohort Study
- 2017
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Ingår i: Journal of Environmental Health Perspectives. - 0091-6765 .- 1552-9924. ; 125:4, s. 691-698
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: As part of the lipidome, oxylipins are bioactive lipid compounds originating from oxidation of different fatty acids. Oxylipins could provide a new target in the developmental origins model or the ability of early life exposure to change biology.OBJECTIVES: We studied the association between in utero PM2.5 (particulate matter with aerodynamic diameter <2.5µm) exposure and oxylipin profiles in newborns.METHODS: Thirty-seven oxylipins reflecting the cyclooxygenase (COX), lipoxygenase (5-LOX and 12/15-LOX) and cytochrome P450 (CYP) pathways were assayed in 197 cord blood plasma samples from the ENVIRONAGE birth cohort. Principal component (PC) analysis and multiple regression models were used to estimate associations of in utero PM2.5 exposure with oxylipin pathways and individual metabolites.RESULTS: A principal component representing the 5-LOX pathway (6 metabolites) was significantly positively associated with PM2.5 exposure during the entire (multiple testing-adjusted q-value = 0.05) and second trimester of pregnancy (q = 0.05). A principal component representing the 12/15-LOX pathway (11 metabolites) was positively associated with PM2.5 exposure during the second trimester of pregnancy (q = 0.05). PM2.5 was not significantly associated with the COX pathway during any time period. There was a positive but non-significant association between second trimester PM2.5 and the CYP pathway (q = 0.16).CONCLUSION: In utero exposure to particulate matter, particularly during the second trimester, was associated with differences in the cord blood levels of metabolites derived from the lipoxygenase pathways. These differences may indicate an effect of air pollution during in utero life on the inflammatory state of the newborn at birth. Oxylipins may be important mediators between early life exposures and health outcomes later in life.
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| 8. |
- Merid, Simon Kebede, et al.
(författare)
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Epigenome-wide meta-analysis of blood DNA methylation in newborns and children identifies numerous loci related to gestational age
- 2020
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Ingår i: Genome Medicine. - Stockholm : Karolinska Institutet, Dept of Clinical Science and Education, Södersjukhuset. - 1756-994X.
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Tidskriftsartikel (refereegranskat)abstract
- Background: Preterm birth and shorter duration of pregnancy are associated with increased morbidity in neonatal and later life. As the epigenome is known to have an important role during fetal development, we investigated associations between gestational age and blood DNA methylation in children. Methods: We performed meta-analysis of Illumina's HumanMethylation450-array associations between gestational age and cord blood DNA methylation in 3648 newborns from 17 cohorts without common pregnancy complications, induced delivery or caesarean section. We also explored associations of gestational age with DNA methylation measured at 4-18 years in additional pediatric cohorts. Follow-up analyses of DNA methylation and gene expression correlations were performed in cord blood. DNA methylation profiles were also explored in tissues relevant for gestational age health effects: fetal brain and lung. Results: We identified 8899 CpGs in cord blood that were associated with gestational age (range 27-42 weeks), at Bonferroni significance, P < 1.06 × 10- 7, of which 3343 were novel. These were annotated to 4966 genes. After restricting findings to at least three significant adjacent CpGs, we identified 1276 CpGs annotated to 325 genes. Results were generally consistent when analyses were restricted to term births. Cord blood findings tended not to persist into childhood and adolescence. Pathway analyses identified enrichment for biological processes critical to embryonic development. Follow-up of identified genes showed correlations between gestational age and DNA methylation levels in fetal brain and lung tissue, as well as correlation with expression levels. Conclusions: We identified numerous CpGs differentially methylated in relation to gestational age at birth that appear to reflect fetal developmental processes across tissues. These findings may contribute to understanding mechanisms linking gestational age to health effects.
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| 9. |
- Nagrani, Rajini, et al.
(författare)
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Association of urinary and ambient black carbon, and other ambient air pollutants with risk of prediabetes and metabolic syndrome in children and adolescents.
- 2023
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Ingår i: Environmental pollution (Barking, Essex : 1987). - : Elsevier BV. - 1873-6424 .- 0269-7491. ; 317
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Tidskriftsartikel (refereegranskat)abstract
- The effects of exposure to black carbon (BC) on various diseases remains unclear, one reason being potential exposure misclassification following modelling of ambient air pollution levels. Urinary BC particles may be a more precise measure to analyze the health effects of BC. We aimed to assess the risk of prediabetes and metabolic syndrome (MetS) in relation to urinary BC particles and ambient BC and to compare their associations in 5453 children from IDEFICS/I. Family cohort. We determined the amount of BC particles in urine using label-free white-light generation under femtosecond pulsed laser illumination. We assessed annual exposure to ambient air pollutants (BC, PM2.5 and NO2) at the place of residence using land use regression models for Europe, and we calculated the residential distance to major roads (≤250m vs. more). We analyzed the cross-sectional relationships between urinary BC and air pollutants (BC, PM2.5 and NO2) and distance to roads, and the associations of all these variables to the risk of prediabetes and MetS, using logistic and linear regression models. Though we did not observe associations between urinary and ambient BC in overall analysis, we observed a positive association between urinary and ambient BC levels in boys and in children living ≤250m to a major road compared to those living >250m away from a major road. We observed a positive association between log-transformed urinary BC particles and MetS (ORper unit increase=1.72, 95% CI=1.21; 2.45). An association between ambient BC and MetS was only observed in children living closer to a major road. Our findings suggest that exposure to BC (ambient and biomarker) may contribute to the risk of MetS in children. By measuring the internal dose, the BC particles in urine may have additionally captured non-residential sources and reduced exposure misclassification. Larger studies, with longitudinal design including measurement of urinary BC at multiple time-points are warranted to confirm our findings.
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| 10. |
- Nawrot, Tim S, et al.
(författare)
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Oxidative properties of ambient PM2.5 and elemental composition : heterogeneous associations in 19 European cities
- 2009
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Ingår i: Atmospheric Environment. - : Elsevier BV. - 1352-2310 .- 1873-2844. ; 43:30, s. 4595-4602
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Tidskriftsartikel (refereegranskat)abstract
- We assessed the extent to which constituents of PM2.5 (transition metals, sodium, chloride) contribute to the ability to generate hydroxyl radicals (OH) in vitro in PM2.5 sampled at 20 locations in 19 European centres participating in the European Community Respiratory Health Survey. PM2.5 samples (n = 716) were collected on filters over one year and the oxidative activity of particle suspensions obtained from these filters was then assessed by measuring their ability to generate OH in the presence of hydrogen peroxide. Associations between OH formation and the studied PM constituents were heterogeneous. The total explained variance ranged from 85% in Norwich to only 6% in Albacete. Among the 20 centres, 15 showed positive correlations between one or more of the measured transition metals (copper, iron, manganese, lead, vanadium and titanium) and OH formation. In 9 of 20 centres OH formation was negatively associated with chloride, and in 3 centres with sodium. Across 19 European cities, elements which explained the largest variations in OH formation were chloride, iron and sodium.
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