@article{D'AgostiniBurgerFranssenetal.2021, author = {D'Agostini, Martina and Burger, Andreas M. and Franssen, Mathijs and Claes, Nathalie and Weymar, Mathias and Leupoldt, Andreas von and Van Diest, Ilse}, title = {Effects of transcutaneous auricular vagus nerve stimulation on reversal learning, tonic pupil size, salivary alpha-amylase, and cortisol}, series = {Psychophysiology : journal of the Society for Psychophysiological Research}, volume = {58}, journal = {Psychophysiology : journal of the Society for Psychophysiological Research}, number = {10}, publisher = {Wiley-Blackwell}, address = {Malden, Mass. [u.a.]}, issn = {1469-8986}, doi = {10.1111/psyp.13885}, pages = {20}, year = {2021}, abstract = {This study investigated whether transcutaneous auricular vagus nerve stimulation (taVNS) enhances reversal learning and augments noradrenergic biomarkers (i.e., pupil size, cortisol, and salivary alpha-amylase [sAA]). We also explored the effect of taVNS on respiratory rate and cardiac vagal activity (CVA). Seventy-one participants received stimulation of either the cymba concha (taVNS) or the earlobe (sham) of the left ear. After learning a series of cue-outcome associations, the stimulation was applied before and throughout a reversal phase in which cue-outcome associations were changed for some (reversal), but not for other (distractor) cues. Tonic pupil size, salivary cortisol, sAA, respiratory rate, and CVA were assessed at different time points. Contrary to our hypothesis, taVNS was not associated with an overall improvement in performance on the reversal task. Compared to sham, the taVNS group performed worse for distractor than reversal cues. taVNS did not increase tonic pupil size and sAA. Only post hoc analyses indicated that the cortisol decline was steeper in the sham compared to the taVNS group. Exploratory analyses showed that taVNS decreased respiratory rate but did not affect CVA. The weak and unexpected effects found in this study might relate to the lack of parameters optimization for taVNS and invite to further investigate the effect of taVNS on cortisol and respiratory rate.}, language = {en} } @misc{GiraudierVenturaBortBurgeretal.2022, author = {Giraudier, Manon and Ventura-Bort, Carlos and Burger, Andreas M. and Claes, Nathalie and D'Agostini, Martina and Fischer, Rico and Franssen, Mathijs and Kaess, Michael and Koenig, Julian and Liepelt, Roman and Nieuwenhuis, Sander and Sommer, Aldo and Usichenko, Taras and Van Diest, Ilse and von Leupoldt, Andreas and Warren, Christopher Michael and Weymar, Mathias}, title = {Evidence for a modulating effect of transcutaneous auricular vagus nerve stimulation (taVNS) on salivary alpha-amylase as indirect noradrenergic marker: A pooled mega-analysis}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {808}, issn = {1866-8364}, doi = {10.25932/publishup-57766}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-577668}, pages = {1378 -- 1388}, year = {2022}, abstract = {Background Non-invasive transcutaneous auricular vagus nerve stimulation (taVNS) has received tremendous attention as a potential neuromodulator of cognitive and affective functions, which likely exerts its effects via activation of the locus coeruleus-noradrenaline (LC-NA) system. Reliable effects of taVNS on markers of LC-NA system activity, however, have not been demonstrated yet. Methods The aim of the present study was to overcome previous limitations by pooling raw data from a large sample of ten taVNS studies (371 healthy participants) that collected salivary alpha-amylase (sAA) as a potential marker of central NA release. Results While a meta-analytic approach using summary statistics did not yield any significant effects, linear mixed model analyses showed that afferent stimulation of the vagus nerve via taVNS increased sAA levels compared to sham stimulation (b = 0.16, SE = 0.05, p = 0.001). When considering potential confounders of sAA, we further replicated previous findings on the diurnal trajectory of sAA activity. Conclusion(s) Vagal activation via taVNS increases sAA release compared to sham stimulation, which likely substantiates the assumption that taVNS triggers NA release. Moreover, our results highlight the benefits of data pooling and data sharing in order to allow stronger conclusions in research.}, language = {en} } @article{GiraudierVenturaBortBurgeretal.2022, author = {Giraudier, Manon and Ventura-Bort, Carlos and Burger, Andreas M. and Claes, Nathalie and D'Agostini, Martina and Fischer, Rico and Franssen, Mathijs and Kaess, Michael and Koenig, Julian and Liepelt, Roman and Nieuwenhuis, Sander and Sommer, Aldo and Usichenko, Taras and Van Diest, Ilse and von Leupoldt, Andreas and Warren, Christopher Michael and Weymar, Mathias}, title = {Evidence for a modulating effect of transcutaneous auricular vagus nerve stimulation (taVNS) on salivary alpha-amylase as indirect noradrenergic marker: A pooled mega-analysis}, series = {Brain Stimulation}, volume = {15}, journal = {Brain Stimulation}, edition = {6}, publisher = {Elsevier}, address = {New York, NY, USA}, issn = {1876-4754}, doi = {10.1016/j.brs.2022.09.009}, pages = {1378 -- 1388}, year = {2022}, abstract = {Background Non-invasive transcutaneous auricular vagus nerve stimulation (taVNS) has received tremendous attention as a potential neuromodulator of cognitive and affective functions, which likely exerts its effects via activation of the locus coeruleus-noradrenaline (LC-NA) system. Reliable effects of taVNS on markers of LC-NA system activity, however, have not been demonstrated yet. Methods The aim of the present study was to overcome previous limitations by pooling raw data from a large sample of ten taVNS studies (371 healthy participants) that collected salivary alpha-amylase (sAA) as a potential marker of central NA release. Results While a meta-analytic approach using summary statistics did not yield any significant effects, linear mixed model analyses showed that afferent stimulation of the vagus nerve via taVNS increased sAA levels compared to sham stimulation (b = 0.16, SE = 0.05, p = 0.001). When considering potential confounders of sAA, we further replicated previous findings on the diurnal trajectory of sAA activity. Conclusion(s) Vagal activation via taVNS increases sAA release compared to sham stimulation, which likely substantiates the assumption that taVNS triggers NA release. Moreover, our results highlight the benefits of data pooling and data sharing in order to allow stronger conclusions in research.}, language = {en} } @article{SicKrausMadletal.2014, author = {Sic, Heiko and Kraus, Helene and Madl, Josef and Flittner, Karl-Andreas and von Muenchow, Audrey Lilly and Pieper, Kathrin and Rizzi, Marta and Kienzler, Anne-Kathrin and Ayata, Korcan and Rauer, Sebastian and Kleuser, Burkhard and Salzer, Ulrich and Burger, Meike and Zirlik, Katja and Lougaris, Vassilios and Plebani, Alessandro and Roemer, Winfried and Loeffler, Christoph and Scaramuzza, Samantha and Villa, Anna and Noguchi, Emiko and Grimbacher, Bodo and Eibel, Hermann}, title = {Sphingosine-1-phosphate receptors control B-cell migration through signaling components associated with primary immunodeficiencies, chronic lymphocytic leukemia, and multiple sclerosis}, series = {The journal of allergy and clinical immunology}, volume = {134}, journal = {The journal of allergy and clinical immunology}, number = {2}, publisher = {Elsevier}, address = {New York}, issn = {0091-6749}, doi = {10.1016/j.jaci.2014.01.037}, pages = {420 -- +}, year = {2014}, abstract = {Background: Five different G protein-coupled sphingosine-1-phosphate (S1P) receptors (S1P1-S1P5) regulate a variety of physiologic and pathophysiologic processes, including lymphocyte circulation, multiple sclerosis (MS), and cancer. Although B-lymphocyte circulation plays an important role in these processes and is essential for normal immune responses, little is known about S1P receptors in human B cells. Objective: To explore their function and signaling, we studied B-cell lines and primary B cells from control subjects, patients with leukemia, patients with S1P receptor inhibitor-treated MS, and patients with primary immunodeficiencies. Methods: S1P receptor expression was analyzed by using multicolor immunofluorescence microscopy and quantitative PCR. Transwell assays were used to study cell migration. S1P receptor internalization was visualized by means of time-lapse imaging with fluorescent S1P receptor fusion proteins expressed by using lentiviral gene transfer. B-lymphocyte subsets were characterized by means of flow cytometry and immunofluorescence microscopy. Results: Showing that different B-cell populations express different combinations of S1P receptors, we found that S1P1 promotes migration, whereas S1P4 modulates and S1P2 inhibits S1P1 signals. Expression of CD69 in activated B lymphocytes and B cells from patients with chronic lymphocytic leukemia inhibited S1P-induced migration. Studying B-cell lines, normal B lymphocytes, and B cells from patients with primary immunodeficiencies, we identified Bruton tyrosine kinase, beta-arrestin 2, LPS-responsive beige-like anchor protein, dedicator of cytokinesis 8, and Wiskott-Aldrich syndrome protein as critical signaling components downstream of S1P1. Conclusion: Thus S1P receptor signaling regulates human B-cell circulation and might be a factor contributing to the pathology of MS, chronic lymphocytic leukemia, and primary immunodeficiencies.}, language = {en} } @misc{BuergerMagdansGies2016, author = {B{\"u}rger, Andreas and Magdans, Uta and Gies, Hermann}, title = {Adsorption of amino acids on the magnetite-(111)-surface: a force field study (vol 19, 851, 2013)}, series = {Journal of molecular modeling}, volume = {22}, journal = {Journal of molecular modeling}, publisher = {Springer}, address = {New York}, issn = {1610-2940}, doi = {10.1007/s00894-016-3124-8}, pages = {3}, year = {2016}, language = {en} }