A proposed study on the transplacental transport of parabens in the human placental perfusion model.

Human exposure to parabens as a preservative used in personal care products is of increasing concern, as there is evidence from in vivo and in vitro studies of hormone disruption in association with exposure to parabens. Transport across the placenta could be critical for risk assessment, but the available data are sparse. The aim is to develop a method for estimating fetal exposure, via the placenta, to the most commonly-used parabens, by using a human placental perfusion model. The use of human tissue is vital for determining human fetal exposure, because animal studies are of little relevance, since the placenta exhibits significant interspecies variation. An HPLC model is currently being established to simultaneously quantify four different parabens, namely, methylparaben, ethylparaben, propylparaben and butylparaben, and their main metabolite, p-hydroxybenzoic acid. With this model, we aim to determine the transport kinetics of these parabens across the human placenta, and to investigate placental metabolism, including differences in transport due to molecular characteristics. This will facilitate assessment of the risks associated with the use of paraben-containing products during pregnancy.

Regional divergence and time trends in the prevalence of gestational diabetes mellitus: a national Danish cohort study.

AIMS: To evaluate the prevalence and time trends of gestational diabetes mellitus (GDM) across the five regions of Denmark with uniform national guidelines for screening and diagnosing GDM. METHODS: This register-based national cohort study included 287,684 births from 2013 to 2017. Trends in GDM prevalence over time and differences between the five regions were evaluated. Crude and adjusted odd ratios (ORs) for GDM were calculated including potential confounding clinical risk factors as age, BMI, educational level, marital status, parity, country of origin and assisted reproduction. RESULTS: From 2013 to 2017, GDM prevalence in Denmark increased by 7% per year (OR 1.07, 95% CI 1.06-1.09, P < 0.001). GDM prevalence varied considerably between regions and ranged from 3.0 to 5.9% in 2017, corresponding to a maximal regional difference of 97%. In crude analyses, the risk of GDM in 2017 was significantly different in four of five regions compared to the remaining regions (OR ranging from 0.60 to 1.55), and these differences persisted after adjusting for confounding clinical risk factors (adjusted OR: 0.59-1.45). CONCLUSION: The prevalence of GDM increased over time in all Danish regions with substantial regional divergence. Up to a 97%, difference in GDM prevalence was observed between Danish regions, which was not explained by available clinical risk factors. This occurred despite national guidelines and raises the question of whether regional variations in screening efficacy, diagnostic procedures or inequality in clinical health care access may explain the observed differences.

Cardiovascular health effects of oral and pulmonary exposure to multi-walled carbon nanotubes in ApoE-deficient mice.

Exposure to high aspect ratio nanomaterials, such as multi-walled carbon nanotubes (MWCNTs) may be associated with increased risk of atherosclerosis, pulmonary disease, and cancer. In the present study, we investigated the cardiovascular and pulmonary health effects of 10 weeks of repeated oral or pulmonary exposures to MWCNTs (4 or 40µg each week) in Apolipoprotein E-deficient (ApoE-/-) mice fed a Western-type diet. Intratracheal instillation of MWCNTs was associated with oxidative damage to DNA in lung tissue and elevated levels of lipid peroxidation products in plasma, whereas the exposure only caused a modest pulmonary inflammation in terms of increased numbers of lymphocytes in bronchoalveolar lavage fluid. Ultrasound imaging in live animals revealed an increase in the inner and outer wall thickness of the aortic arch at 10 weeks after pulmonary exposure to MWCNTs, which may suggest artery remodelling. However, we did not find accelerated plaque progression in the aorta or the brachiocephalic artery by histopathology. Furthermore, repeated oral exposure to MWCNTs did not cause changes in the composition of gut microbiota of exposed mice. Collectively, this study indicates that repeated pulmonary exposure to MWCNTs was associated with oxidative stress, whereas cardiovascular effects encompassed remodelling of the aorta wall.