225 research outputs found
Placental DEPTOR as a stress sensor during pregnancy
The author(s) has paid for this article to be freely available under the terms of the Creative Commons Attribution Non-Commercial Licence (http://creativecommons.org/licenses/by-nc/2.5/) which permits unrestricted non-commercial use, distribution and reproduction in any medium, provided the original work is properly cited. Copyright @ 2012 Portland Press. The article has been made available through the Brunel Open Access Publishing Fund.DEPTOR [DEP-domain-containing and mTOR (mammalian target of rapamycin)-interacting protein] is a modulator of mTOR signalling that binds to mTORC (mTOR complex) 1 and mTORC2. However, to date, the precise functions of DEPTOR are not fully elucidated, particularly in reproductive tissues where mTOR acts as a placental nutrient sensor. Pregnancy is associated with major physiological and psychosocial changes and adaptation to these changes is crucial for normal fetal development. In the present study, we tested the hypothesis that maternal stress can affect mTOR signalling at term, and, as a result, influence placental growth. We first investigated the expression of DEPTOR, mTOR, rictor (rapamycin-insensitive companion of mTOR) and raptor (regulatory associated protein of mTOR) from human placentas (n=23) using Q-PCR (quantitative PCR), and correlated these data to days of pregnancy and maternal stress, as well as placental and fetal weight. Maternal and fetal cortisol levels were also measured. JEG-3 and BeWo cells, used as placental in vitro models, were treated with cortisol and DEPTOR expression was assessed using Q-PCR. DEPTOR appears to be the predominant transcript in the human placenta compared with mTOR, rictor and raptor in both term (n=13) and preterm (n=10) placentas as assessed by Q-PCR. There was a significantly lower level only of log-DEPTOR gene expression in the high stress group (-1.34) than in the low stress group (0.07; t₂₀=2.41, P=0.026). Interestingly, mothers with high stress had significantly elevated levels of cortisol (8555 pg/ml) compared with those with low stress (4900 pg/ml). We then tested the hypothesis that cortisol can directly affect DEPTOR expression. When BeWo cells were treated with cortisol 10, 100 and 1000 nM, the expression of DEPTOR was significantly down-regulated by 50, 41 and 39% (all P<0.05) respectively when compared with basal levels. Treatment of JEG-3 cells with cortisol, led to a significant decrease of DEPTOR expression at 100 nM (39%, P<0.05) and at 1000 nM (73%, P<0.01). These novel findings are indicative of a higher order of complexity of DEPTOR signalling in the human placenta that is affected by maternal stress, which could affect pregnancy outcome
Immune system function, stress, exercise and nutrition profile can affect pregnancy outcome: Lessons from a Mediterranean cohort
This article is made available through the Brunel Open Access Publishing Fund.Pregnancy is associated with major physiological and future psychosocial changes, and maternal adaptation to these changes is crucial for normal foetal development. Psychological stress in pregnancy predicts an earlier birth and lower birth weight. Pregnancy-specific stress contributes directly to preterm delivery. The importance of nutrition and exercise during pregnancy with regard to pregnancy outcome has long been acknowledged. This importance has only been further emphasized by the recent changes in food quality and availability, lifestyle changes and a new understanding of foetal programming's effects on adult outcomes. We hypothesised that for a successful pregnancy certain events at a nutritional, immune, psycho-emotional and genetic level should be tightly linked. Therefore, in this study we followed an ‘integrative’ approach to investigate how maternal stress, nutrition, pregnancy planning and exercise influence pregnancy outcome. A key finding of our study is that there was a significant reduction in the intake of alcohol, caffeine-containing and sugary drinks during pregnancy. However, passive smoking in the household remained unchanged. In terms of immune profile, a significant inverse correlation was noted between difficulty to ‘fight’ an infection and number of colds (r=-0.289, P=0.003) as well as the number of infections (r=-0.446, P<0.0001) during pregnancy. The vast majority of the pregnant women acquired a more sedentary lifestyle in the third trimester. In planned, but not in unplanned, pregnancies stress predicted infant weight, independent of age and body mass index (BMI). Notably, in mothers with negative attitudes towards the pregnancy, those with an unplanned pregnancy gave birth to infants with significantly higher weights than those with planned pregnancies. Collectively these data suggest that there is a higher order of complexity, possibly involving gene-environment interactions that work together to ensure a positive outcome for the mother as well as the foetus
Differential expression of placental glucocorticoid receptors and growth arrest-specific transcript 5 in term and preterm pregnancies: evidence for involvement of maternal stress.
This article has been made available through the Brunel Open Access Publishing Fund.Pregnancy-specific stress predicts birth outcomes. We hypothesized that there is a maternal stress-GR interaction that can influence fetal birth weight. This study examined the relationship between mothers' stress and attitude towards their pregnancies, placental glucocorticoid receptors (GRs) and growth arrest-specific transcript 5 (GAS5) expression, and the status of GR polymorphism, with their infants' birth weights. GAS5 and GR α were the predominant transcripts in both term and preterm placentas, with GAS5 being primarily localized in the syncytiotrophoblasts. In an attempt to mimic moderate and high stress environment in vitro, BeWo and JEG-3 cytotrophoblast cell lines were treated with 10 nM-1000 nM cortisol. Only expression of GAS5 was significantly upregulated by cortisol in all treatments compared with basal levels, but none of the GRs changed expression significantly. In an attempt to assess a stress versus gene interaction, we studied four GR polymorphisms. In the homozygous group for Tth111I polymorphism, mothers with negative attitudes towards the pregnancy gave birth to infants with significantly lower birth weights compared to women with positive/neutral attitudes. None of the GR splice variants were associated with maternal stress. However, placental GAS5 levels were inversely correlated with maternal stress. This study points towards a potential gene-environment interaction that could be of predictive value for fetal weight.Brunel Open Access Publishing Fun
Photoexcited triplet states of twisted acenes investigated by Electron Paramagnetic Resonance
Twisting of the acene backbone out of planarity in twisted acenes leads to a variation in their optical and electronic properties. The effect of increasing twist angles on the properties of the photoexcited triplet states of a series of anthracene-based helically tethered twisted acenes is investigated here by Electron Paramagnetic Resonance (EPR) spectroscopy. Increasing signal intensities with increasing twist angles indicate increased intersystem crossing efficiencies for the twisted molecules compared to the untethered reference compound. Variations in the electron spin polarisation observed in the transient EPR spectra, in particular for the compound with the shortest tether, imply changes in the sublevel population kinetics depending on molecular geometry. Changes in the zero-field splitting parameters and in the proton hyperfine couplings for compounds with short tethers and therefore higher twist angles point towards a slight redistribution of the spin density compared to the parent compound. The experimental results can be explained by considering both an increase in twist angle and a related decrease in the dihedral angle between the phenyl side groups and the acene core. The observation of a clear excitation-wavelength dependence suggests preferential excitation of different molecular conformations, with conformers characterised by higher twist angles selected at higher wavelengths
Affective Polarization in Multiparty Systems? Comparing Affective Polarization Towards Voters and Parties in Norway and the United States
A growing body of comparative studies on partisan hostility – a phenomenon known as affective polarization – is providing evidence that partisan affective polarization is generally no greater in the United States than it is in many European multiparty systems. This article takes the comparative literature on affective polarization one step further by presenting the first comparative study on affective polarization that simultaneously uses, compares and combines a direct measure of affective polarization towards voters (using the inter-party marriage measure) and an indirect measure of affective polarization towards parties (using the like/dislike of party measure) while accounting for the fact that multiparty systems have numerous political parties. This is done by comparing the levels of affective polarization in the United States and Norway. The results show greater affective polarization in the United States relating to parties, but the differences between these two countries are indistinguishable from chance when focusing on the affect relating to voters. This provides empirical evidence that comparative evidence of negative affect towards parties cannot necessarily be generalized to suggest that there is comparative evidence of negative affect towards voters. Yet the results also suggest that negative feelings towards out-parties move to some extent to the personal level in terms of negative feelings towards voters of these out-parties.publishedVersio
The pro-social neurohormone oxytocin reverses the actions of the stress hormone cortisol in human ovarian carcinoma cells in vitro
Copyright: © Mankarious et al. The journey patients with ovarian cancer travel from non-specific symptoms causing delayed diagnosis through surgery and chemotherapy, culminating in a 5-year survival rate of 43%, must have a profound and detrimental psychological impact on patients. Emerging studies link higher levels of oxytocin (OT) and increased social support, an independent prognostic factor in cancer, with a moderating effect on stress. In contrast, there is a known association of tumour cell proliferation with elevated cortisol (stress hormone) levels. We hypothesise therefore that there is cross-talk between cortisol and oxytocin at a molecular level. Three ovarian cancer cell lines, used as in vitro models, were treated with cortisol at concentrations mimicking physiological stress in vivo in the presence or absence of OT. OT reduced cell proliferation and migration, induced apoptosis and autophagy for all three cell lines, partially reversing the effects of cortisol. Quantitative RT-PCR of tissue taken from ovarian cancer patients revealed that the glucocorticoid receptor (splice variant GR-P) and OT receptor (OTR) were significantly upregulated compared to controls. Tissue microarray revealed that the expression of GRα was lower in the ovarian cancer samples compared to normal tissue. OT is also shown to drive alternative splicing of the GR gene and cortisol-induced OTR expression. OT was able to transactivate GR in the presence of cortisol thus providing further evidence of cross-talk in vitro. These data provide explanations for why social support might help distressed ovarian cancer patients and help define novel hypotheses regarding potential therapeutic interventions in socially isolated patients
Role of Heart Rate Variability in the Association between Myocardial Infarction Severity and Post-Myocardial Infarction Distress
Objective: Myocardial infarction (MI) results in mental health consequences, including depression and post-traumatic stress disorder (PTSD). The risk and protective factors of such mental consequences are not fully understood. This study examined the relation between MI severity and future mental health consequences and the moderating role of vagal nerve activity. Methods: In a reanalysis of data from the Myocardial Infarction-Stress Prevention Intervention (MI-SPRINT) troponin levels. Depression and PTSD symptoms were assessed with valid questionnaires, both at 3 and 12 months. Vagal nerve activity was indexed by the heart rate variability (HRV) parameter of the root-mean square of successive R-R differences (RMSSD). Following multivariate analyses, the association between MI severity and distress was examined in patients with low and high HRV (RMSSD = 30 ms). Results: In the full sample, the Killip index predicted post-MI distress only at 3 months, while troponin predicted distress at 3- and 12-months post-MI. However, HRV moderated the effects of the Killip classification; Killip significantly predicted symptoms of depression and PTSD at 3- and 12-months post-MI, but only in patients with low HRV. Such moderation was absent for troponin. Conclusion: MI severity (Killip classification) predicted post-MI depression and PTSD symptoms, but only in patients with low HRV, suggesting that the vagal nerve is a partial protective (moderating) factor in the relation between Killip score and post-MI distress
NGO Legitimacy: Four Models
The aim of this paper is to examine NGOs’ legitimacy in the context of global politics. In order to yield a better understanding of NGOs’ legitimacy at the international level it is important to examine how their legitimacy claims are evaluated. This paper proposes dividing the literature into four models based on the theoretical and analytical approaches to their legitimacy claims: the market model, social change model, new institutionalism model and the critical model. The legitimacy criteria generated by the models are significantly different in their analytical scope of how one is to assess the role of NGOs operating as political actors contributing to democracy. The paper argues that the models present incomplete, and sometimes conflicting, views of NGOs’ legitimacy and that this poses a legitimacy dilemma for those assessing the political agency of NGOs in world politics. The paper concludes that only by approaching their legitimacy holistically can the democratic role of NGOs be explored and analysed in the context of world politics
Evaluation Research and Institutional Pressures: Challenges in Public-Nonprofit Contracting
This article examines the connection between program evaluation research and decision-making by public managers. Drawing on neo-institutional theory, a framework is presented for diagnosing the pressures and conditions that lead alternatively toward or away the rational use of evaluation research. Three cases of public-nonprofit contracting for the delivery of major programs are presented to clarify the way coercive, mimetic, and normative pressures interfere with a sound connection being made between research and implementation. The article concludes by considering how public managers can respond to the isomorphic pressures in their environment that make it hard to act on data relating to program performance.This publication is Hauser Center Working Paper No. 23. The Hauser Center Working Paper Series was launched during the summer of 2000. The Series enables the Hauser Center to share with a broad audience important works-in-progress written by Hauser Center scholars and researchers
New Developments in Understanding Cardiovascular Disease and the Implications for Social Work
Cardiovascular disease is now viewed as an inflammatory disease. An index of chronic inflammation (viz., C-Reactive Protein) is as good a predictor of heart attacks as are fats in blood. The data suggest that stressful events are so closely associated with chronic inflammatory states, that the body’s stress response can be viewed as an inflammatory state. This paper summarizes and explains the link between stress and cardiovascular disease. Negative health outcomes, particularly for cardiovascular diseases, are higher among those of lower socio-economic status. Differential stress among socio-economic tiers is considered as an explanation for the disparities. The literature linking cardiovascular risk factors to the stressors of workplace unfairness and lack of control over working conditions is reviewed. The role of the stressor of racism in explaining the higher rates of cardiovascular mortality in African Americans is discussed. Finally, for societies with wider gaps in income between the rich and the poor, increased stress is explored as a possible explanation for the diminished health outcomes found across all socio-economic tiers. The implications for social work direct practice and macro-practice are considered
- …