Neural circuits of emotion regulation: a comparison of mindfulness-based and cognitive reappraisal strategies

Dealing with one's emotions is a core skill in everyday life. Effective cognitive control strategies have been shown to be neurobiologically represented in prefrontal structures regulating limbic regions. In addition to cognitive strategies, mindfulness-associated methods are increasingly applied in psychotherapy. We compared the neurobiological mechanisms of these two strategies, i.e. cognitive reappraisal and mindfulness, during both the cued expectation and perception of negative and potentially negative emotional pictures. Fifty-three healthy participants were examined with functional magnetic resonance imaging (47 participants included in analysis). Twenty-four subjects applied mindfulness, 23 used cognitive reappraisal. On the neurofunctional level, both strategies were associated with comparable activity of the medial prefrontal cortex and the amygdala. When expecting negative versus neutral stimuli, the mindfulness group showed stronger activations in ventro- and dorsolateral prefrontal cortex, supramarginal gyrus as well as in the left insula. During the perception of negative versus neutral stimuli, the two groups only differed in an increased activity in the caudate in the cognitive group. Altogether, both strategies recruited overlapping brain regions known to be involved in emotion regulation. This result suggests that common neural circuits are involved in the emotion regulation by mindfulness-based and cognitive reappraisal strategies. Identifying differential activations being associated with the two strategies in this study might be one step towards a better understanding of differential mechanisms of change underlying frequently used psychotherapeutic interventions.

PLACENTAL GLUCOSE TRANSPORTER (GLUT)-1 REGULATION IN PREECLAMPSIA

PLACENTAL GLUCOSE TRANSPORTER (GLUT)-1 REGULATION IN PREECLAMPSIA Camilla Marini a,b, Benjamin P. Lüscher a,b, Marianne J€orger-Messerli a,b, Ruth Sager a,b, Xiao Huang c, Jürg Gertsch c, Matthias A. Hediger c, Christiane Albrecht c, Marc U. Baumann a,c, Daniel V. Surbek a,c a Department of Obstetrics and Gynecology, University Hospital of Bern, Bern, Switzerland, Switzerland; b Department of Clinical Research, University of Bern, Bern, Switzerland, Switzerland; c Institute for Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland, Switzerland Objectives: Glucose is a primary energy source for the fetus. The absence of significant gluconeogenesis in the fetus means that the fetal up-take of this vital nutrient is dependent on maternal supply and subsequent transplacental transport. Altered expression and/or function of placental transporters may affect the intrauterine environment and could compromise fetal and mother well-being. We speculated that pre-eclampsia (PE) impairs the placental glucose transport system. Methods: Placentae were obtained after elective caesarean sections following normal pregnancies and pre-eclamptic pregnancies. Syncytial basal membrane (BM) and apical microvillus membrane (MVM) fractions were prepared using differential ultra-centrifugation and magnesium precipitation. Protein expression was assessed by western blot analysis. mRNA levels in whole villous tissue lysate were quantified by real-time PCR. To assess glucose transport activity a radiolabeled substrate up-take assay and a transepithelial transport model using primary cytotrophoblasts were established. Results: GLUT1 mRNA expression was not changed in PE when compared to control, whereas protein expression was significantly down-regulated. Glucose up-take into syncytial microvesicles was reduced in PE compared to control. In a transepithelial transport model, phloretinmediated inhibition of GLUT1 at the apical side of primary cytotrophoblasts showed a 44% of reduction of transepithelial glucose transport at IC50. Conclusions: GLUT1 is down-regulated on protein and functional level in PE compared to control. Altering glucose transport activity by inhibition of apical GLUT-1 indicates that transplacental glucose transport might be regulated on the apical side of the syncytiotrophoblast. These results might help to understand better the regulation of GLUT1 transporter and maybe in future to develop preventive strategies to modulate the fetal programming and thereby reduce the incidence of disease for both the mother and her child later in life.

Inflammatory markers in pediatric stroke: An attempt to better understanding the pathophysiology

BACKGROUND The mechanisms of childhood and perinatal arterial ischemic stroke (AIS) are poorly understood. Multiple risk factors include cerebral arteriopathy, congenital cardiac disease, infection, sickle cell disease, and maternal-fetal conditions in neonates. For infections and parainfectious conditions being the most important a possible inflammatory pathophysiology has long been suspected. This pilot study aims to detect, whether there are any abnormalities of inflammatory markers associated with childhood and neonatal stroke. METHODS The concentration of 23 different metalloproteinases (MMPs), tissue inhibitors of MMPs (TIMPs), endothelial factors, vascular cell adhesion proteins, and cytokines in plasma were measured in 12 children with AIS, 7 healthy age matched controls and 6 full term neonates with perinatal AIS. RESULTS At the time of the acute event children with AIS had significantly elevated levels of MMP-9, TIMP4, IL-6, IL-8 and CRP compared to controls (p < 0.05). Except for lower IL-6 and CRP levels the pattern of children with a history of varizella-zoster virus (VZV) and other viral infections did not differ to the non-infectious group. Median levels of MMP-1, MMP-2, TIMP-1, TIMP-2, sE-selectin, sICAM-1, sVCAM-1, IL-8, IL-10, TNF-alpha, VEGF, Fetuin A were found to be higher in the neonatal group when compared with older children. CONCLUSION This pilot study supports the assumption of an inflammatory process and up-regulation of metalloproteinases and their inhibitors, and altered pattern of circulating pro-inflammatory cytokines, CRP and vWF levels in pediatric and neonatal AIS. It highlights the feasibility but also difficulties for similar larger future studies that should aim to clarify childhood stroke etiopathogenesis and consecutive further therapeutic options.

Regulation of T cell function by complement C5A in mice during mycobacterial infection

Tuberculosis is the leading cause of death in the world due to a single infectious agent, making it critical to investigate all aspects of the immune response mounted against the causative agent, Mycobacterium tuberculosis , in order to better treat and prevent disease. Previous observations show a disparity in the ability to control mycobacterial growth between mouse strains sufficient in C5, such as C57BL/6 and B10.D2/nSnJ, and those naturally deficient in C5, such as A/J and B10.D2/nSnJ, with C5 deficient mice being more susceptible. It has been shown that during M. tuberculosis infection, C5 deficient macrophages have a defect in production of interleukin (IL)-12, a cytokine involved in the cyclical activation between infected macrophages and effector T cells. T cells stimulated by IL-12 produce interferon (IFN)-γ, the signature cytokine of T helper type 1 (Th1) cells. It is known that a cell-mediated Th1 response is crucial for control of M. tuberculosis in the lungs of humans and mice. This study demonstrates that murine T cells express detectable levels of CD88, a receptor for C5a (C5aR), following antigen presentation by macrophages infected with mycobacteria. T cells from C5 deficient mice infected with M. tuberculosis were found to secrete less IFN-γ and had a reduced Th1 phenotype associated with fewer cells expressing the transcription factor, T-box expressed in T cells (T-bet). The altered Th1 phenotype in M. tuberculosis infected C5 deficient mice coincided with a rise in IL-4 and IL-10 secretion from Th2 cells and inducible regulatory T cells, respectively. It was found that the ineffective T cell response to mycobacteria in C5 deficient mice was due indirectly to a lack of C5a via poor priming by infected macrophages and possibly by a direct interaction between T cells and C5a peptide. Therefore, these studies show a link between the cells of the innate and adaptive arms of the immune system, macrophages and T cells respectively, that was mediated by C5a using a mouse model of M. tuberculosis infection. ^

SFRP4 regulation of Wnt7a signaling and cellular proliferation in the endometrium

In the endometrium, hormonal effects on epithelial cells are often elicited through stromal hormone receptors via unknown paracrine mechanisms. Several lines of evidence support the hypothesis that Wnts participate in stromal-epithelial cell communication and thus mediate hormone action. Characterization of specific Wnt signaling components in the endometrium was performed using cellular localization studies and evaluating hormone effects in a rat model. Wnt7a was expressed in the luminal epithelium, whereas the extracellular Wnt modulator, SFRP4, was localized to the endometrial stroma. SFRP4 expression is significantly decreased in endometrial carcinoma and aberrant Wnt7a signaling has been shown to cause uterine defects and contribute to the onset of disease. The specific Fzds and SFRPs that bind Wnt7a and the particular signal transduction pathway each Wnt7a-Fzd pair activates have not been identified. Additionally, the function of Wnt7a and SFRP4 in the endometrium has not been addressed. A survey of all Wnt signaling proteins expressed in the endometrium was conducted and Fzd5 and Fzd10 were identified as two receptors capable of transducing the Wnt7a signal. Biologically active recombinant Wnt7a and SFRP4 proteins were purified for quantitative biochemical studies. In Ishikawa cells, Wnt7a binding to Fzd5 activated β-catenin/canonical Wnt signaling and increased cellular proliferation. Wnt7a signaling mediated by Fzd10 induced a non-canonical/JNK-responsive pathway. SFRP4 suppressed Wnt7a action in both an autocrine and paracrine manner. Treatment with SFRP4 protein and overexpression of SFRP4 inhibited endometrial cancer cell growth and induced apoptosis in vitro. A split-eGFP complementation assay was developed to visually detect Wnt7a-Fzd interactions and subsequent pathway activation in cells. By employing a unique ELISA-based protein-protein binding technique, it was demonstrated that Wnt7a binds to SFRP4 and Fzd5 with equal nanomolar affinity. The development of these novel biological tools could lead to a better understanding of Wnt-protein interactions and the identification of new modulators of Wnt signaling. This study supports a mechanism by which the nature of the Wnt7a signal in the endometrium is dependent upon the Fzd repertoire of the cell and can be regulated by SFRP4. The potential tumor suppressor function of SFRP4 suggests it may serve as a therapeutic target for endometrial carcinoma. ^

Regulation of squamous cell differentiation in human head and neck carcinoma cells by retinoids

Retinoids have been found to be effective in the prevention of premalignant lesions and second primary cancers in the upper aerodigestive tract. Further development of retinoids for prevention and therapy of head and neck squamous cell carcinoma (HNSCC) requires a better understanding of their mechanism of action on the growth and differentiation of such cells. I have chosen to employ cultured HNSCC cell lines as a model system for investigating the mechanism underlying the effects of retinoids. These cells are useful because all-trans retinoic acid (ATRA) inhibits their proliferation. Furthermore, two HNSCC cell lines were found to express three squamous differentiation (SqD) markers characteristic of normal keratinocytes and ATRA suppressed the expression of these markers as reported for normal keratinocytes. It is thought that nuclear retinoic acid receptors (RARs and RXRs), which act as DNA-binding transcription modulating factors, mediate the effects of retinoids on the growth and differentiation of normal and tumor cells. I found that all four cell lines examined expressed RAR-$\alpha ,$ RAR-$\tau ,$ and RXR-$\alpha$ and three of four expressed RAR-$\beta .$ ATRA treatment increased the level of RAR-$\alpha ,$ -$\beta ,$ and -$\tau$ in four cell lines. Two HNSCC cell lines that exhibited a progressive increase in the expression of SqD markers during growth in culture also showed a concurrent decrease in RAR-$\beta$ level. Moreover, increasing concentrations of RA suppressed the SqD marker while inducing RAR-$\beta$ mRNA. Several synthetic retinoids which exhibit a preference for binding to specific nuclear RARs showed a differential ability to inhibit cell proliferation, transactivate transcription of the reporter genes (CAT and luciferase) from the RA response element (RARE) of the RAR-$\beta$ gene, and induce RAR-$\beta$ expression. Those retinoids that were effective inducers of RAR-$\beta$ also suppressed SqD effectively, indicating an inverse relationship exists between the expression of RAR-$\beta$ and SqD. This inverse relationship suggests a role for RAR-$\beta$ in the suppression of SqD. ^

Systems Biology Approaches to Probe Gene Regulation in Bacteria

Mechanisms that allow pathogens to colonize the host are not the product of isolated genes, but instead emerge from the concerted operation of regulatory networks. Therefore, identifying components and the systemic behavior of networks is necessary to a better understanding of gene regulation and pathogenesis. To this end, I have developed systems biology approaches to study transcriptional and post-transcriptional gene regulation in bacteria, with an emphasis in the human pathogen Mycobacterium tuberculosis (Mtb). First, I developed a network response method to identify parts of the Mtb global transcriptional regulatory network utilized by the pathogen to counteract phagosomal stresses and survive within resting macrophages. As a result, the method unveiled transcriptional regulators and associated regulons utilized by Mtb to establish a successful infection of macrophages throughout the first 14 days of infection. Additionally, this network-based analysis identified the production of Fe-S proteins coupled to lipid metabolism through the alkane hydroxylase complex as a possible strategy employed by Mtb to survive in the host. Second, I developed a network inference method to infer the small non-coding RNA (sRNA) regulatory network in Mtb. The method identifies sRNA-mRNA interactions by integrating a priori knowledge of possible binding sites with structure-driven identification of binding sites. The reconstructed network was useful to predict functional roles for the multitude of sRNAs recently discovered in the pathogen, being that several sRNAs were postulated to be involved in virulence-related processes. Finally, I applied a combined experimental and computational approach to study post-transcriptional repression mediated by small non-coding RNAs in bacteria. Specifically, a probabilistic ranking methodology termed rank-conciliation was developed to infer sRNA-mRNA interactions based on multiple types of data. The method was shown to improve target prediction in Escherichia coli, and therefore is useful to prioritize candidate targets for experimental validation.

Regulation of intracellular pH in cnidarians: response to acidosis in Anemonia viridis

The regulation of intracellular pH (pHi) is a fundamental aspect of cell physiology that has received little attention in studies of the phylum Cnidaria, which includes ecologically important sea anemones and reef-building corals. Like all organisms, cnidarians must maintain pH homeostasis to counterbalance reductions in pHi, which can arise because of changes in either intrinsic or extrinsic parameters. Corals and sea anemones face natural daily changes in internal fluids, where the extracellular pH can range from 8.9 during the day to 7.4 at night. Furthermore, cnidarians are likely to experience future CO2-driven declines in seawater pH, a process known as ocean acidification. Here, we carried out the first mechanistic investigation to determine how cnidarian pHi regulation responds to decreases in extracellular and intracellular pH. Using the anemone Anemonia viridis, we employed confocal live cell imaging and a pH-sensitive dye to track the dynamics of pHi after intracellular acidosis induced by acute exposure to decreases in seawater pH and NH4Cl prepulses. The investigation was conducted on cells that contained intracellular symbiotic algae (Symbiodinium sp.) and on symbiont-free endoderm cells. Experiments using inhibitors and Na-free seawater indicate a potential role of Na/H plasma membrane exchangers (NHEs) in mediating pHi recovery following intracellular acidosis in both cell types. We also measured the buffering capacity of cells, and obtained values between 20.8 and 43.8 mM per pH unit, which are comparable to those in other invertebrates. Our findings provide the first steps towards a better understanding of acid-base regulation in these basal metazoans, for which information on cell physiology is extremely limited.

Could the acid-base status of Antarctic sea urchins indicate a better-than-expected resilience to near-future ocean acidification?

Increasing atmospheric carbon dioxide concentration alters the chemistry of the oceans towards more acidic conditions. Polar oceans are particularly affected due to their low temperature, low carbonate content and mixing patterns, for instance upwellings. Calcifying organisms are expected to be highly impacted by the decrease in the oceans' pH and carbonate ions concentration. In particular, sea urchins, members of the phylum Echinodermata, are hypothesized to be at risk due to their high-magnesium calcite skeleton. However, tolerance to ocean acidification in metazoans is first linked to acid-base regulation capacities of the extracellular fluids. No information on this is available to date for Antarctic echinoderms and inference from temperate and tropical studies needs support. In this study, we investigated the acid-base status of 9 species of sea urchins (3 cidaroids, 2 regular euechinoids and 4 irregular echinoids). It appears that Antarctic regular euechinoids seem equipped with similar acid-base regulation systems as tropical and temperate regular euechinoids but could rely on more passive ion transfer systems, minimizing energy requirements. Cidaroids have an acid-base status similar to that of tropical cidaroids. Therefore Antarctic cidaroids will most probably not be affected by decreasing seawater pH, the pH drop linked to ocean acidification being negligible in comparison of the naturally low pH of the coelomic fluid. Irregular echinoids might not suffer from reduced seawater pH if acidosis of the coelomic fluid pH does not occur but more data on their acid-base regulation are needed. Combining these results with the resilience of Antarctic sea urchin larvae strongly suggests that these organisms might not be the expected victims of ocean acidification. However, data on the impact of other global stressors such as temperature and of the combination of the different stressors needs to be acquired to assess the sensitivity of these organisms to global change.

A supramolecular basis for CD45 tyrosine phosphatase regulation in sustained T cell activation

Transmembrane protein tyrosine phosphatases, such as CD45, can act as both positive and negative regulators of cellular signaling. CD45 positively modulates T cell receptor (TCR) signaling by constitutively priming p56lck through the dephosphorylation of the C-terminal negative regulatory phosphotyrosine site. However, CD45 can also exert negative effects on cellular processes, including events triggered by integrin-mediated adhesion. To better understand these opposing actions of tyrosine phosphatases, the subcellular compartmentalization of CD45 was imaged by using laser scanning confocal microscopy during functional TCR signaling of live T lymphocytes. On antigen engagement, CD45 was first excluded from the central region of the interface between the T cell and the antigen-presenting surface where CD45 would inhibit integrin activation. Subsequently, CD45 was recruited back to the center of the contact to an area adjacent to the site of sustained TCR engagement. Thus, CD45 is well positioned within a supramolecular assembly in the vicinity of the engaged TCR, where CD45 would be able to maintain src-kinase activity for the duration of TCR engagement.

Arabidopsis mutant analysis and gene regulation define a nonredundant role for glutamate dehydrogenase in nitrogen assimilation.

Glutamate dehydrogenase (GDH) is ubiquitous to all organisms, yet its role in higher plants remains enigmatic. To better understand the role of GDH in plant nitrogen metabolism, we have characterized an Arabidopsis mutant (gdh1-1) defective in one of two GDH gene products and have studied GDH1 gene expression. GDH1 mRNA accumulates to highest levels in dark-adapted or sucrose-starved plants, and light or sucrose treatment each repress GDH1 mRNA accumulation. These results suggest that the GDH1 gene product functions in the direction of glutamate catabolism under carbon-limiting conditions. Low levels of GDH1 mRNA present in leaves of light-grown plants can be induced by exogenously supplied ammonia. Under such conditions of carbon and ammonia excess, GDH1 may function in the direction of glutamate biosynthesis. The Arabidopsis gdh-deficient mutant allele gdh1-1 cosegregates with the GDH1 gene and behaves as a recessive mutation. The gdh1-1 mutant displays a conditional phenotype in that seedling growth is specifically retarded on media containing exogenously supplied inorganic nitrogen. These results suggest that GDH1 plays a nonredundant role in ammonia assimilation under conditions of inorganic nitrogen excess. This notion is further supported by the fact that the levels of mRNA for GDH1 and chloroplastic glutamine synthetase (GS2) are reciprocally regulated by light.

Towards Better Use of Credit Reporting in Europe. CEPS-ECRI Task Force Report, September 2013

This report discusses how the current EU credit reporting systems meet the demands of the different stakeholders in the credit granting and management process, and what is needed to improve these systems. As credit reporting is a tool for responsible lending and for ensuring financial inclusion of consumers, it argues that the needs of EU credit markets and consumers should be the basis for assessing the current regulation and its functionality. How a creditor assesses the risk and the creditworthiness of a customer is at the core of successful and safe crediting. Facilitating this assessment process, within the boundaries of data protection laws, is a key building block for making well-informed credit decisions.

Does EU regulation hinder or stimulate innovation? CEPS Special Report No. 96, 19 November 2014

Introduction. One frequently hears the question posed in the title to this report, but there is little systematic analytical literature on the issue. Fragmented evidence or anecdotes dominate debates among EU regulatory decision-makers and in European business, insofar as there is a genuine debate at all. This CEPS Special Report focuses on the multi-faceted, ambiguous and complex relationship between (EU) regulation and innovation in the economy, and discusses the innovation-enhancing potential of certain regulatory approaches as well as factors that tend to reduce incentives to innovate. It adopts an 'ecosystem' approach to both regulation and innovation, and study the interactions between the two ecosystems. This general analysis and survey are complemented by seven case studies of EU regulation enabling and disabling innovation, two horizontal and five sectoral ones. The case studies are preceded by a broader contextual analysis of trends in EU regulation over the last three decades. These trends show the significant transformation of the nature as well as improvement of the quality of EU regulation, largely in the deepened internal market, which tend to have a favourable and lasting effect on the rate of innovation in the EU (other things being equal). Among the findings include the following: Regulation can at times be a powerful stimulus to innovation. EU regulation matters at all stages of the innovation process. Different types of regulation can be identified in terms of innovation impact: general or horizontal, innovation-specific and sector-specific regulation. More prescriptive regulation tends to hamper innovative activity, whereas the more flexible EU regulation is, the better innovation can be stimulated. Lower compliance and red-tape burdens have a positive effect on innovation. The authors recommend incorporating a specific test on innovation impacts in the ex-ante impact assessment of EU legislation as well as in ex-post evaluation. There is ample potential for fostering innovation by reviewing the EU regulatory acquis.

Understanding human genome regulation through entropic graph-based regularization and submodular optimization

Thesis (Ph.D.)--University of Washington, 2016-06

Function and Regulation of Cytochrome P450 4V2 and the Implications in Bietti’s Crystalline Dystrophy

Thesis (Ph.D.)--University of Washington, 2016-06