Photometric defocus observations of transiting extrasolar planets

We have carried out photometric follow-up observations of bright transiting extrasolar planets using the CbNUOJ 0.6m telescope. We have tested the possibility of obtaining high photometric precision by applying the telescope defocus technique allowing the use of several hundred seconds in exposure time for a single measurement. We demonstrate that this technique is capable of obtaining a root-mean-square scatter of order sub-millimagnitude over several hours for a V $\sim$ 10 host star typical for transiting planets detected from ground-based survey facilities. We compare our results with transit observations with the telescope operated in in-focus mode. High photometric precision is obtained due to the collection of a larger amount of photons resulting in a higher signal compared to other random and systematic noise sources. Accurate telescope tracking is likely to further contribute to lowering systematic noise by probing the same pixels on the CCD. Furthermore, a longer exposure time helps reducing the effect of scintillation noise which otherwise has a significant effect for small-aperture telescopes operated in in-focus mode. Finally we present the results of modelling four light-curves for which a root-mean-square scatter of 0.70 to 2.3 milli-magnitudes have been achieved.Comment: 12 pages, 11 figures, 5 tables. Submitted to Journal of Astronomy and Space Sciences (JASS

The association between city-level air pollution and frailty among the elderly population in China

This study is supported by China Scholarship Council (CSC), People's Republic of China and Population and Health Research Group, School of Geography and Sustainable Development, University of St Andrews, United Kingdom.A growing body of research suggests that air pollution negatively affects specific health outcomes, but how long- and short-term exposure to air pollution are associated with frailty is unclear. Using longitudinal data from adults aged 65 and over from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) linked with air quality index data, we model a frailty score according to the city-level of air pollution exposure, adjusting for individual socio-demographic factors and city-level indicators. All models show increased frailty with higher exposure to air pollution in one year prior to the interview, when controlling for short-term fluctuations. Moreover, elderly people living in areas where air pollution increased over the follow-up had larger increases in frailty scores than those where air pollution was relatively constant. The results suggest that air pollution plays a role in healthy ageing.PostprintPeer reviewe

Childhood maltreatment, dissociation and borderline personality disorder: Preliminary data on the mediational role of mentalizing in complex post-traumatic stress disorder

Objectives: Treatments for borderline personality disorder (BPD) and post-traumatic stress disorder (PTSD) are less effective for patients with co-occurring symptoms of both disorders, who are considered to have complex PTSD (cPTSD), compared with patients with either condition alone. Evidence suggests that co-occurrence of symptoms indicates greater impairment in mentalizing. This study examines evidence for targeting mentalizing when treating individuals with co-occurring symptoms, irrespective of their exposure to developmental trauma and, for the first time, investigates the mediational role of mentalizing in the associations between BPD symptomatology and cPTSD.// Design: We identified in a routine clinical service a group of patients with BPD, with or without co-occurring symptoms of PTSD. We hypothesized that patients with co-occurring symptoms and a history of childhood maltreatment will show more severe clinical profiles and greater mentalizing problems, which in turn lead to symptoms consistent with cPTSD.// Method: Clinical profiles of 72 patients with BPD (43 with and 29 without co-occurring symptoms of PTSD; mean age in both groups 28 years, 79% and 83% female, respectively) were identified using the Structured Clinical Interview for DSM-IV Axis II Disorders. Patients completed self-report measures of BPD and PTSD symptoms, well-being, dissociation and reflective functioning. Childhood trauma histories were evaluated.// Results: Compared with patients with BPD-only, those with co-occurring BPD and PTSD showed greater severity in terms of BPD and dissociative symptoms, met a broader range of BPD diagnostic criteria, had a greater sense of personal worthlessness and self-evaluated their well-being as considerably diminished. This group was also more inclined to recall increased instances of childhood sexual abuse. In a mediation analysis, mentalizing acted as a partial mediator for the relationship between BPD severity and cPTSD, as well as between dissociative symptoms and cPTSD. Interestingly, mentalizing did not mediate the relationship between childhood sexual abuse and cPTSD.// Conclusions: Overall, the correlational findings are consistent with an intended focus on mentalizing to treat cPTSD symptoms in individuals who also meet criteria for a diagnosis of BPD

a prospective clinical trial

Background Continuous glucose monitoring (CGM) has not yet been implemented in the intensive care unit (ICU) setting. The purpose of this study was to evaluate reliability, feasibility, nurse acceptance and accuracy of the Medtronic Sentrino® CGM system in critically ill patients. Methods Sensors were inserted into the subcutaneous tissue of the patient’s thigh, quantifying interstitial glucose concentration for up to 72 h per sensor. Reliability and feasibility analysis included frequency of data display, data gaps and reasons for sensor removal. We surveyed nurse acceptance in a questionnaire. For the accuracy analysis, we compared sensor values to glucose values obtained via blood gas analysis. Potential benefits of CGM were investigated in intra- individual analyses of factors, such as glycemic variability or time in target range achieved with CGM compared to that achieved with intermittent glucose monitoring. Results The device generated 68,655 real-time values from 31 sensors in 20 critically ill patients. 532 comparative blood glucose values were collected. Data were displayed during 32.5 h [16.0/62.4] per sensor, which is 45.1 % of the expected time of 72 h and 84.8 % of 37.9 h actual monitoring time. 21 out of 31 sensors were removed prematurely. 79.1 % of the nursing staff rated the device as not beneficial; the response rate was one- third. Mean absolute relative difference was 15.3 % (CI 13.5–17.0 %). Clarke error grid: 76.9 % zone A, 21.6 % zone B, 0.2 % zone C, 0.9 % zone D, 0.4 % zone E. Bland–Altman plot: mean bias +0.53 mg/dl, limits of agreement +64.6 and −63.5 mg/dl. Accuracy deteriorated during elevated glycemic variability and in the hyperglycemic range. There was no reduction in dysglycemic events during CGM compared to 72 h before and after CGM. If CGM was measuring accurately, it identified more hyperglycemic events when compared to intermittent measurements. This study was not designed to evaluate potential benefits of CGM on glucose control. Conclusions The subcutaneous CGM system did not perform with satisfactory accuracy, feasibility, or nursing acceptance when evaluated in 20 medical-surgical ICU patients. Low point accuracy and prolonged data gaps significantly limited the potential clinical usefulness of the CGM trend data. Accurate continuous data display, with a MARD < 14 %, showed potential benefits in a subgroup of our patients. Trial registration NCT02296372; Ethic vote Charité EA2/095/1

Interpersonal stress regulation and the development of anxiety disorders: an attachment-based developmental framework

Anxiety disorders represent a common but often debilitating form of psychopathology in both children and adults. While there is a growing understanding of the etiology and maintenance of these disorders across various research domains, only recently have intergrative accounts been proposed. While classical attachment history has been a traditional core construct in phychological models of anxiety, contemporary attachment theory has the potential to integrate neurobiological and behavioral findings within a multidisciplinary developmental framework. The current paper proposes a modern attachement theory-based developmental model grounded in relevant literature form multiple disciplines including social neuroscience, genetics, neuroendocrinology, and the study of family factors involved in the development of anxiety disorders. Recent account of stress regulation hav highlighted the interplay between stress, anxiety, and activation of the attachement system. This interplay directly affects the development of social-cognitive and mentalizing capacities that are acquired in the interpersonal context of early attachemnt relationships. Early attachement experiences are conceptualized as the key organizer of a complex interplay between genetic, environmental, and epigenetic contributions to the development of anxiety disorders - a multifactorial etiology resulting from dysfunctional co-regulation of fear and stress states. These risk-conferring processes are characterized by hyperactivation strategies in the face of anxiety. The cumulative allostatic load and subsequent "wear and tear" effects associated with hyperactivation strategies converge on the neural pathways of anxiety and stress. Attachement experiences further influence the development of anxiety as potential moderators of risk factors, differentially impacting on genetic vulnerability and relevant neurobiological pathways. Implications for further research and potential treatments are outlined

Association between potassium concentrations, variability and supplementation, and in‑hospital mortality in ICU patients: a retrospective analysis

BACKGROUND: Serum potassium concentrations are commonly between 3.5 and 5.0 mmol/l. Standardised protocols for potassium range and supplementation in the ICU are lacking. The purpose of this retrospective analysis of ICU patients was to investigate potassium concentrations, variability and supplementation, and their association with in-hospital mortality. METHODS: ICU patients ≥ 18 years, with ≥ 2 serum potassium values, treated at the Charité - Universitätsmedizin Berlin between 2006 and 2018 were eligible for inclusion. We categorised into groups of mean potassium concentrations:  3.5-4.0, > 4.0-4.5, > 4.5-5.0, > 5.0-5.5, > 5.5 mmol/l and potassium variability: 1st, 2nd and ≥ 3rd standard deviation (SD). We analysed the association between the particular groups and in-hospital mortality and performed binary logistic regression analysis. Survival curves were performed according to Kaplan-Meier and tested by Log-Rank. In a subanalysis, the association between potassium supplementation and in-hospital mortality was investigated. RESULTS: In 53,248 ICU patients with 1,337,742 potassium values, the lowest mortality (3.7%) was observed in patients with mean potassium concentrations between > 3.5 and 4.0 mmol/l and a low potassium variability within the 1st SD. Binary logistic regression confirmed these results. In a subanalysis of 22,406 ICU patients (ICU admission: 2013-2018), 12,892 (57.5%) received oral and/or intravenous potassium supplementation. Potassium supplementation was associated with an increase in in-hospital mortality in potassium categories from > 3.5 to 4.5 mmol/l and in the 1st, 2nd and ≥ 3rd SD (p < 0.001 each). CONCLUSIONS: ICU patients may benefit from a target range between 3.5 and 4.0 mmol/l and a minimal potassium variability. Clear potassium target ranges have to be determined. Criteria for widely applied potassium supplementation should be critically discussed. Trial registration German Clinical Trials Register, DRKS00016411. Retrospectively registered 11 January 2019, http://www.drks.de/DRKS00016411

Targeted ablation of oligodendrocytes induces axonal pathology independent of overt demyelination

The critical role of oligodendrocytes in producing and maintaining myelin that supports rapid axonal conduction in CNS neurons is well established. More recently, additional roles for oligodendrocytes have been posited, including provision of trophic factors and metabolic support for neurons. To investigate the functional consequences of oligodendrocyte loss, we have generated a transgenic mouse model of conditional oligodendrocyte ablation. In this model, oligodendrocytes are rendered selectively sensitive to exogenously administered diphtheria toxin (DT) by targeted expression of the diphtheria toxin receptor in oligodendrocytes. Administration of DT resulted in severe clinical dysfunction with an ascending spastic paralysis ultimately resulting in fatal respiratory impairment within 22 d of DT challenge. Pathologically, at this time point, mice exhibited a loss of ∼26% of oligodendrocyte cell bodies throughout the CNS. Oligodendrocyte cell-body loss was associated with moderate microglial activation, but no widespread myelin degradation. These changes were accompanied with acute axonal injury as characterized by structural and biochemical alterations at nodes of Ranvier and reduced somatosensory-evoked potentials. In summary, we have shown that a death signal initiated within oligodendrocytes results in subcellular changes and loss of key symbiotic interactions between the oligodendrocyte and the axons it ensheaths. This produces profound functional consequences that occur before the removal of the myelin membrane, i.e., in the absence of demyelination. These findings have clear implications for the understanding of the pathogenesis of diseases of the CNS such as multiple sclerosis in which the oligodendrocyte is potentially targeted

Deep sequencing reveals differential expression of microRNAs in favorable versus unfavorable neuroblastoma

Small non-coding RNAs, in particular microRNAs(miRNAs), regulate fine-tuning of gene expression and can act as oncogenes or tumor suppressor genes. Differential miRNA expression has been reported to be of functional relevance for tumor biology. Using next-generation sequencing, the unbiased and absolute quantification of the small RNA transcriptome is now feasible. Neuroblastoma(NB) is an embryonal tumor with highly variable clinical course. We analyzed the small RNA transcriptomes of five favorable and five unfavorable NBs using SOLiD next-generation sequencing, generating a total of >188 000 000 reads. MiRNA expression profiles obtained by deep sequencing correlated well with real-time PCR data. Cluster analysis differentiated between favorable and unfavorable NBs, and the miRNA transcriptomes of these two groups were significantly different. Oncogenic miRNAs of the miR17-92 cluster and the miR-181 family were overexpressed in unfavorable NBs. In contrast, the putative tumor suppressive microRNAs, miR-542-5p and miR-628, were expressed in favorable NBs and virtually absent in unfavorable NBs. In-depth sequence analysis revealed extensive post-transcriptional miRNA editing. Of 13 identified novel miRNAs, three were further analyzed, and expression could be confirmed in a cohort of 70 NBs