61 research outputs found
Effect of Obesity on Acute Ozone-Induced Changes in Airway Function, Reactivity, and Inflammation in Adult Females
We previously observed greater ozone-induced lung function decrements in obese than non-obese women. Animal models suggest that obesity enhances ozone-induced airway reactivity and inflammation. In a controlled exposure study, we compared the acute effect of randomized 0.4ppm ozone and air exposures (2 h with intermittent light exercise) in obese (N = 20) (30<BMI<40Kg/m2) vs. non-obese (N = 20) (BMI<25Kg/m2) non-smoking 18–35 year old women. We measured spirometry and bronchial reactivity to inhaled methacholine (3h post-exposure). Inflammation and obesity markers were assessed in the blood (pre, 4h post, and 20h post exposures) and induced-sputum (4h post-exposures and on 24h pre-exposure training day, no exercise): measures of C reactive protein (CRP) (blood only), leptin (blood only), adiponectin, interleukins IL-6, IL-1b, and IL-8, and tumor necrosis factor alpha, and sputum cell differential cell counts. The pre- to post-exposure decrease in forced vital capacity after ozone (adjusted for the change after air exposure) was significantly greater in the obese group (12.5+/-7.5 vs. 8.0+/-5.8%, p<0.05). Post ozone exposure, 6 obese and 6 non-obese subjects responded to methacholine at ≤ 10mg/ml (the maximum dose); the degree of hyperresponsiveness was similar for the two groups. Both BMI groups showed similar and significant ozone-induced increases in sputum neutrophils. Plasma IL-6 was increased by exercise (4 hr post air exposure vs. pre) only in the obese but returned to pre-air exposure levels at 20hr post-exposure. Plasma IL-6 was significantly increased at 4hr post ozone exposure in both groups and returned to pre-exposure levels by 20h post-exposure. These results confirm our previous findings of greater post-ozone spirometric decrements in obese young women. However, acute ozone-induced airway reactivity to methacholine and airway inflammation did not differ by obesity at the exposure and exercise levels used
IGF-I and IGFBP-3 Polymorphisms in Relation to Circulating Levels among African American and Caucasian Women
Circulating insulin-like growth factor-one (IGF-I) and IGF binding protein-3 (IGFBP-3) levels have been associated with common diseases. Although family-based studies suggest that genetic variation contributes to circulating IGF-I and IGFBP-3 levels, analyses of associations with multiple IGF-I and IGFBP-3 single nucleotide polymorphisms (SNPs) have been limited, especially among African Americans. We evaluated 30 IGF-I and 15 IGFBP-3 SNPs and estimated diplotypes in association with plasma IGF-I and IGFBP-3 among 984 premenopausal African American and Caucasian women. In both races, IGFBP-3 rs2854746 (Ala32Gly) was positively associated with plasma IGFBP-3 (CC versus GG mean difference among Caucasians = 631 ng/ml, 95% confidence interval: 398, 864; African Americans = 897 ng/ml, 95% confidence interval: 656, 1138), and IGFBP-3 diplotypes with the rs2854746 GG genotype had lower mean IGFBP-3 levels than referent diplotypes with the CG genotype, while IGFBP-3 diplotypes with the CC genotype had higher mean IGFBP-3 levels. IGFBP-3 rs2854744 (−202 A/C) was in strong linkage disequilibrium with rs2854746 in Caucasians only, but was associated with plasma IGFBP-3 in both races. Eight additional IGFBP-3 SNPs were associated with 5% or greater differences in mean IGFBP-3 levels, with generally consistent associations between races. Twelve IGF-I SNPs were associated with 10% or greater differences in mean IGF-I levels, but associations were generally discordant between races. Diplotype associations with plasma IGF-I did not parallel IGF-I SNP associations. Our study supports that common IGFBP-3 SNPs, especially rs2854746, influence plasma IGFBP-3 levels among African Americans and Caucasians, but provides less evidence that IGF-I SNPs affect plasma IGF-I levels
Anti-Müllerian Hormone and Lifestyle, Reproductive, and Environmental Factors Among Women in Rural South Africa
Few data exist regarding antiMüllerian hormone, a marker of ovarian reserve, in relation to environmental factors with potential ovarian toxicity
Anti-Müllerian hormone and lifestyle, reproductive, and environmental factors among women in rural South Africa
BACKGROUND :
Few data exist regarding anti-Müllerian hormone, a marker of ovarian reserve, in relation to environmental factors with potential ovarian toxicity.
METHODS :
This analysis included 420 women from Limpopo, South Africa studied in 2010-2011. Women were administered comprehensive questionnaires, and plasma concentrations of anti-Müllerian hormone and dichlorodiphenyltrichloroethane were determined. We used separate multivariable models to examine the associations between natural log-transformed anti-Müllerian hormone concentration (ng/ml) and each of the lifestyle, reproductive, and environmental factors of interest, adjusted for age, body mass index, education, and parity.
RESULTS :
The median age of women was 24 years (interquartile range [IQR] = 22 to 26); the median anti-Müllerian hormone concentration was 3.1 ng/ml (IQR = 2.0 to 6.0). Women who reported indoor residual spraying in homes with painted walls (indicative of exposure to pyrethroids) had 25% lower (95% confidence interval [CI] = -39%, -8%) anti-Müllerian hormone concentrations compared with women who reported no spraying. Little evidence of decreased anti-Müllerian hormone concentrations was observed among women with the highest dichlorodiphenyltrichloroethane levels. Compared with women who used an electric stove, no association was observed among women who cooked indoors over open wood fires. The findings also suggested lower anti-Müllerian hormone concentrations among women who drank coffee (-19% [95% CI = -31%, -5%]) or alcohol (-21% [95% CI = -36%, -3%]).
CONCLUSIONS :
These are among the first data regarding anti-Müllerian hormone concentrations relative to pesticides and indoor air pollution. Our results are suggestive of decreased ovarian reserve associated with exposure to pyrethroid pesticides, which is consistent with laboratory animal data.http://journals.lww.com/epidem/pages/default.aspx2016-05-31hb201
Exposure to DDT from indoor residual spraying and biomarkers of inflammation among reproductive-aged women from South Africa
BACKGROUND : Evidence from animal studies suggests that DDT and DDE can adversely affect immuno-competence while human data are less conclusive. We aimed to assess the association of plasma concentrations of DDT and DDE with biomarkers of inflammation among reproductive-aged women residing in homes sprayed with DDT through Indoor Residual Spraying (IRS). METHODS : This study included 416 women from the Study of Women and Babies, South Africa (2010–2011). DDT, DDE, and biomarkers of inflammation (immunoglobulins A, G and M, interleukins 1β, 6, and 8, tumor necrosis factor-α, C-reactive protein, serum amyloid-A, intercellular adhesion molecule-1, vascular cell adhesion molecule-1) were quantified in plasma. Linear regression was used to assess associations of DDT and DDE with each natural log-transformed biomarker. Models were adjusted for age, body mass index, parity, income, and season; beta estimates were expressed as percent differences. RESULTS : Compared to women with the lowest plasma concentrations of DDT and DDE, those with the highest concentrations of both compounds had higher levels IL-1β, IL6, and TNF- α. While associations were statistically significant for both DDT and DDE, the magnitude of the associations was slightly stronger for DDT. Compared to women in the lowest quintile of DDT, women in the highest quintile were estimated to have 53.0% (95%CI: 21.7%, 84.4%), 28.1% (95%CI: 6.4%, 49.8%), and 26.6% (95%CI: 12.0%, 41.1%) higher levels of IL-1β, IL6, and TNF- α, respectively. CONCLUSIONS : Our results suggest that increased plasma concentrations of DDT and DDE resulting from exposure to IRS may increase concentrations of pro-inflammatory biomarkers among reproductive-aged women in South Africa.The National Institute of Environmental Health Sciences, National Institutes of Health; and the Intramural Research Program of the NIH, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA.http://www.elsevier.com/locate/envres2021-12-01hj2020School of Health Systems and Public Health (SHSPH
Predictors of plasma DDT and DDE concentrations among women exposed to indoor residual spraying for malaria control in the South African Study of Women and Babies (SOWB)
BACKGROUND : Few studies have examined predictors of DDT (dichlorodiphenyltrichloroethane)
and DDE (dichlorodiphenyldichloroethylene) levels among residents in homes sprayed with DDT
for malaria control with the aim of identifying exposure-reduction strategies.
METHODS : The present analysis included 381 women enrolled in the Study of Women and Babies
(SOWB) during 2010–2011, from eight South African villages in the Limpopo Province, South
Africa. Indoor residual spraying (IRS) occurred in half of the villages. Questionnaires regarding
various demographic and medical factors were administered and blood samples were obtained. We
classified the women into three exposure groups by type of residence: unsprayed village (n = 175),
IRS village in household with a low likelihood of DDT use (non-DDT IRS household, n = 106),
IRS village in household with a high likelihood of DDT use (DDT IRS household, n = 100). We
used multivariable models of natural log-transformed DDT plasma levels (in micrograms per liter)
and DDE (in micrograms per liter) to identify predictors for each group.
RESULTS : Median levels of DDT and DDE among women in unsprayed villages were 0.3 [interquartile
range (IQR): 0.1–0.9] and 1.7 (IQR: 0.7–5.5), respectively. Median levels of DDT and
DDE among women in DDT IRS households were 2.6 (IQR: 1.1–6.6) and 8.5 (IQR: 4.7–18.0),
respectively. In unsprayed villages, women with water piped to the yard, rather than a public tap,
had 73% lower DDT (95% CI: –83, –57%) and 61% lower DDE (95% CI: –74, –40%) levels. In
DDT IRS households, women who reported taking more than six actions to prepare their home
before IRS (e.g., covering water and food) had 40% lower DDT levels (95% CI: –63, –0.3%) than
women who took fewer than four actions.
CONCLUSION : The predictors of DDT and DDE plasma levels identified in the present study may
inform interventions aimed at decreasing exposure. Among households where DDT is likely to be
used for IRS, education regarding home preparations may provide an interventional target.http://ehp.niehs.nih.gov/hb201
Association between Perfluoroalkyl substances and thyroid stimulating hormone among pregnant women: a cross-sectional study
BackgroundPerfluoroalkyl substances (PFASs) are a group of highly persistent chemicals that are widespread contaminants in wildlife and humans. Exposure to PFAS affects thyroid homeostasis in experimental animals and possibly in humans. The objective of this study was to examine the association between plasma concentrations of PFASs and thyroid stimulating hormone (TSH) among pregnant women.MethodsA total of 903 pregnant women who enrolled in the Norwegian Mother and Child Cohort Study from 2003 to 2004 were studied. Concentrations of thirteen PFASs and TSH were measured in plasma samples collected around the 18th week of gestation. Linear regression models were used to evaluate associations between PFASs and TSH.ResultsAmong the thirteen PFASs, seven were detected in more than 60% of samples and perfluorooctane sulfonate (PFOS) had the highest concentrations (median, 12.8ng/mL; inter-quartile range [IQR], 10.1 -16.5ng/mL). The median TSH concentration was 3.5 (IQR, 2.4 - 4.8) μIU/mL. Pregnant women with higher PFOS had higher TSH levels. After adjustment, with each 1ng/mL increase in PFOS concentration, there was a 0.8% (95% confidence interval: 0.1%, 1.6%) rise in TSH. The odds ratio of having an abnormally high TSH, however, was not increased, and other PFASs were unrelated to TSH.ConclusionsOur results suggest an association between PFOS and TSH in pregnant women that is small and may be of no clinical significance
Target company cross-border effects in acquisitions into the UK
We analyse the abnormal returns to target shareholders in crossborder and domestic acquisitions of UK companies. The crossborder effect during the bid month is small (0.84%), although crossborder targets gain significantly more than domestic targets during the months surrounding the bid. We find no evidence for the level of abnormal returns in crossborder acquisitions to be associated with market access or exchange rate effects, and only limited support for an international diversification effect. However, the crossborder effect appears to be associated with significant payment effects, and there is no significant residual crossborder effect once various bid characteristics are controlled for
Hexavalent Chromium Is Carcinogenic to F344/N Rats and B6C3F1 Mice after Chronic Oral Exposure
Perfluoroalkyl substances and lipid concentrations in plasma during pregnancy among women in the Norwegian Mother and Child Cohort Study
Perfluoroalkyl substances (PFASs) are widespread and persistent environmental pollutants. Previous studies, primarily among non-pregnant individuals, suggest positive associations between PFAS levels and certain blood lipids. If there is a causal link between PFAS concentrations and elevated lipids during pregnancy, this may suggest a mechanism by which PFAS exposure leads to certain adverse pregnancy outcomes, including preeclampsia
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