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1.
Hildegunn Norbakken Granslo Elizabeth G. Aarag Fredheim Eirin Esaiassen Lars Christophersen Peter
strup Jensen Tom Eirik Mollnes Claus Moser Trond Flgstad Claus Klingenberg Jorunn Pauline Cavanagh 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2019,127(6):475-483
The global spread of antimicrobial resistance and the increasing number of immune‐compromised patients are major challenges in modern medicine. Targeting bacterial virulence or the human host immune system to increase host defence are important strategies in the search for novel antimicrobial drugs. We investigated the inflammatory response of the synthetic short antimicrobial peptide LTX21 in two model systems: a human whole blood ex vivo model and a murine in vivo peritoneum model – both reflecting early innate immune response. In the whole blood model, LTX21 increased the secretion of a range of different cytokines, decreased the level of tumour necrosis factor (TNF) and activated the complement system. In a haemolysis assay, we found 2.5% haemolysis at a LTX21 concentration of 500 mg/L. In the murine model, increased influx of white blood cells (WBCs) and polymorphonuclear neutrophils (PMNs) in the murine peritoneal cavity was observed after treatment with LTX21. In addition, LTX21 increased monocyte chemoattractant protein‐1 (MCP‐1). In conclusion, LTX21 affected the inflammatory response; the increase in cytokine secretion, complement activation and WBC influx indicates an activated inflammatory response. The present results indicate the impact of LTX21 on the host–pathogen interplay. Whether this will also affect the course of infection has to be investigated. 相似文献
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Recent research emphasizes the importance of social factors during performance monitoring. Thus, the current study investigated the impact of social stimuli -such as communicative gestures- on feedback processing. Moreover, it addressed a shortcoming of previous studies, which failed to consider stimulus complexity as potential confounding factor. Twenty-four volunteers performed a time estimation task while their electroencephalogram was recorded. Either social complex, social non-complex, non-social complex, or non-social non-complex stimuli were used to provide performance feedback. No effects of social dimension or complexity were found for task performance. In contrast, Feedback-Related Negativity (FRN) and P300 amplitudes were sensitive to both factors, with larger FRN and P300 amplitudes after social compared to non-social stimuli, and larger FRN amplitudes after complex positive than non-complex positive stimuli. P2 amplitudes were solely sensitive to feedback valence and social dimension. Subjectively, social complex stimuli were rated as more motivating than non-social complex ones. Independently of each other, social dimension and visual complexity influenced amplitude variation during performance monitoring. Social stimuli seem to be perceived as more salient, which is corroborated by P2, FRN and P300 results, as well as by subjective ratings. This could be explained due to their given relevance during every day social interactions. 相似文献
4.
Stefanie Linder Simone B. Duss Charles Dvok Christoph Merlo Stefan Essig Kali Tal Cinzia Del Giovane Lamprini Syrogiannouli Raphael Heinzer Christoph Nissen Claudio L. A. Bassetti Reto Auer Micheline Maire 《Journal of sleep research》2021,30(1):e13169
Guidelines recommend cognitive behavioural therapy for insomnia (CBT‐I) as first‐line treatment for chronic insomnia, but it is not clear how many primary care physicians (PCPs) in Switzerland prescribe this treatment. We created a survey that asked PCPs how they would treat chronic insomnia and how much they knew about CBT‐I. The survey included two case vignettes that described patients with chronic insomnia, one with and one without comorbid depression. PCPs also answered general questions about treating chronic insomnia and about CBT‐I and CBT‐I providers. Of the 820 Swiss PCPs we invited, 395 (48%) completed the survey (mean age 54 years; 70% male); 87% of PCPs prescribed sleep hygiene and 65% phytopharmaceuticals for the patient who had only chronic insomnia; 95% prescribed antidepressants for the patient who had comorbid depression. In each case, 20% of PCPs prescribed benzodiazepines or benzodiazepine receptor agonists, 8% prescribed CBT‐I, 68% said they knew little about CBT‐I, and 78% did not know a CBT‐I provider. In the clinical case vignettes, most PCPs treated chronic insomnia with phytopharmaceuticals and sleep hygiene despite their lack of efficacy, but PCPs rarely prescribed CBT‐I, felt they knew little about it, and usually knew no CBT‐I providers. PCPs need more information about the benefits of CBT‐I and local CBT‐I providers and dedicated initiatives to implement CBT‐I in order to reduce the number of patients who are prescribed ineffective or potentially harmful medications. 相似文献
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Lukas Frase Peter Selhausen Lukas Krone Sulamith Tsodor Friederike Jahn Bernd Feige Jonathan G. Maier Florian Mainberger Hannah Piosczyk Marion Kuhn Stefan Klöppel Annette Sterr Chiara Baglioni Kai Spiegelhalder Dieter Riemann Michael A. Nitsche Christoph Nissen 《Brain stimulation》2019,12(3):674-683
Background
Arousal and sleep represent basic domains of behavior, and alterations are of high clinical importance.Objective/hypothesis
The aim of this study was to further elucidate the neurobiology of insomnia disorder (ID) and the potential for new treatment developments, based on the modulation of cortical activity through the non-invasive brain stimulation technique transcranial direct current stimulation (tDCS). Specifically, we tested the hypotheses that bi-frontal anodal tDCS shortens and cathodal tDCS prolongs total sleep time in patients with ID, compared to sham stimulation. Furthermore, we tested for differences in indices of arousal between ID patients and healthy controls and explored their potential impact on tDCS effects.Methods
Nineteen ID patients underwent a within-subject repeated-measures sleep laboratory study with adaptation, baseline and three experimental nights. Bifrontal anodal, cathodal and sham tDCS was delivered in a counterbalanced order immediately prior to sleep. Wake EEG was recorded prior to and after tDCS as well as on the following morning. Subsequently, we compared patients with ID to a healthy control group from an earlier dataset.Results
Against our hypothesis, we did not observe any tDCS effects on sleep continuity or sleep architecture in patients with ID. Further analyses of nights without stimulation demonstrated significantly increased levels of arousal in ID patients compared to healthy controls, as indexed by subjective reports, reduced total sleep time, increased wake after sleep onset and increased high frequency EEG power during wakefulness and NREM sleep. Of note, indices of increased arousal predicted the lack of effect of tDCS in ID patients.Conclusions
Our study characterizes for the first time differential effects of tDCS on sleep in patients with ID and healthy controls, presumably related to persistent hyperarousal in ID. These findings suggest that adapted tDCS protocols need to be developed to modulate arousal and sleep dependent on baseline arousal levels. 相似文献6.
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Schmitt Friedhelm C. Büntjen Lars Schütze Hartmut Kaufmann Jörn Heinze Hans-Joachim Hinrichs Hermann Tempelmann Claus Düzel Emrah Voges Jürgen 《Zeitschrift für Epileptologie》2020,33(1):42-49
Clinical Epileptology - Wir berichten über einen 30-jährigen Patienten, der mit 21 Jahren an einer fokalen Epilepsie mit epigastrischen Auren und nicht bewusst erlebten... 相似文献
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Lukas Frase Wolfram Regen Stphanie Kass Albena Rambach Chiara Baglioni Bernd Feige Jürgen Hennig Dieter Riemann Christoph Nissen Kai Spiegelhalder 《Journal of sleep research》2020,29(5)
The current study was designed to further clarify the influence of brain morphology, sleep oscillatory activity and age on memory consolidation. Specifically, we hypothesized, that a smaller volume of hippocampus, parahippocampal and medial prefrontal cortex negatively impacts declarative, but not procedural, memory consolidation. Explorative analyses were conducted to demonstrate whether a decrease in slow‐wave activity negatively impacts declarative memory consolidation, and whether these factors mediate age effects on memory consolidation. Thirty‐eight healthy participants underwent an acquisition session in the evening and a retrieval session in the morning after night‐time sleep with polysomnographic monitoring. Declarative memory was assessed with the paired‐associate word list task, while procedural memory was tested using the mirror‐tracing task. All participants underwent high‐resolution magnetic resonance imaging. Participants with smaller hippocampal, parahippocampal and medial prefrontal cortex volumes displayed a reduced overnight declarative, but not procedural memory consolidation. Mediation analyses showed significant age effects on overnight declarative memory consolidation, but no significant mediation effects of brain morphology on this association. Further mediation analyses showed that the effects of age and brain morphology on overnight declarative memory consolidation were not mediated by polysomnographic variables or sleep electroencephalogram spectral power variables. Thus, the results suggest that the association between age, specific brain area volume and overnight memory consolidation is highly relevant, but does not necessarily depend on slow‐wave sleep as previously conceptualized. 相似文献
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