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Ronny Redlich Ilona Schneider Nicole Kerkenberg Nils Opel Jonas Bauhaus Verena Enneking Jonathan Repple Elisabeth J. Leehr Dominik Grotegerd Claas Khler Katharina Frster Katharina Dohm Susanne Meinert Tim Hahn Harald Kugel Kathrin Schwarte Christiane Schettler Katharina Domschke Volker Arolt Walter Heindel Bernhard T. Baune Weiqi Zhang Christa Hohoff Udo Dannlowski 《Human brain mapping》2020,41(3):594-604
Epigenetic alterations of the brain‐derived neurotrophic factor (BDNF) gene have been associated with psychiatric disorders in humans and with differences in amygdala BDNF mRNA levels in rodents. This human study aimed to investigate the relationship between the functional BDNF‐Val66Met polymorphism, its surrounding DNA methylation in BDNF exon IX, amygdala reactivity to emotional faces, and personality traits. Healthy controls (HC, n = 189) underwent functional MRI during an emotional face‐matching task. Harm avoidance, novelty seeking and reward dependence were measured using the Tridimensional Personality Questionnaire (TPQ). Individual BDNF methylation profiles were ascertained and associated with several BDNF single nucleotide polymorphisms surrounding the BDNF‐Val66Met, amygdala reactivity, novelty seeking and harm avoidance. Higher BDNF methylation was associated with higher amygdala reactivity (x = 34, y = 0, z = ?26, t(166) = 3.00, TFCE = 42.39, p(FWE) = .045), whereby the BDNF‐Val66Met genotype per se did not show any significant association with brain function. Furthermore, novelty seeking was negatively associated with BDNF methylation (r = ?.19, p = .015) and amygdala reactivity (r = ?.17, p = .028), while harm avoidance showed a trend for a positive association with BDNF methylation (r = .14, p = .066). The study provides first insights into the relationship among BDNF methylation, BDNF genotype, amygdala reactivity and personality traits in humans, highlighting the multidimensional relations among genetics, epigenetics, and neuronal functions. The present study suggests a possible involvement of epigenetic BDNF modifications in psychiatric disorders and related brain functions, whereby high BDNF methylation might reduce BDNF mRNA expression and upregulate amygdala reactivity. 相似文献
124.
Il-Kang Na Friedrich Wittenbecher Mikalai Dziubianau Anne Herholz Angela Mensen Désirée Kunkel Olga Blau Igor Blau Eckhard Thiel Lutz Uharek Carmen Scheibenbogen Kathrin Rieger Andreas Thiel 《Haematologica》2013,98(1):23-30
Rabbit antithymocyte globulin-Genzyme™ is used to prevent graft-versus-host disease after allogeneic hematopoietic stem cell transplantation. Common disadvantages of treatment are infectious complications. The effects of rabbit antithymocyte globulin-Genzyme™ on thymic function have not been well-studied. Multicolor flow cytometry was used to analyze the kinetics of conventional and regulatory T cells in adult patients treated (n=12) or not treated (n=8) with rabbit antithymocyte globulin-Genzyme™ during the first 6 months after allogeneic hematopoietic stem cell transplantation. Patients treated with rabbit antithymocyte globulin-Genzyme™ had almost undetectable levels of recent thymic emigrants (CD45RA+CD31+) of both conventional and regulatory CD4T cells throughout the 6 months after allogeneic hematopoietic stem cell transplantation whereas CD4+CD45RA-memory T cells were less affected, but their levels were also significantly lower than in patients not treated with rabbit antithymocyte globulin-Genzyme™. In vitro, rabbit antithymocyte globulin-Genzyme™ induced apoptosis and cytolysis of human thymocytes, and its cytotoxic effects were greater than those of rabbit antithymocyte globulin-Fresenius™. Rabbit antithymocyte globulin-Genzyme™ in combination with a conditioning regimen strongly impairs thymic recovery of both conventional and regulatory CD4+ T cells. The sustained depletion of conventional and regulatory CD4+T cells carries a high risk of both infections and graft-versus-host disease. Our data indicate that patients treated with rabbit antithymocyte globulin-Genzyme™ could benefit from thymus-protective therapies and that trials comparing this product with other rabbit antithymocyte globulin preparations or lymphocyte-depleting compounds would be informative. 相似文献
125.
Eva-Maria Grbner Michael Zeiler Florian Ph. S. Fischmeister Kathrin Kollndorfer Sonja Schmelz Andrea Schneider Nina Haid-Stecher Kathrin Sevecke Gudrun Wagner Lara Keller Roger Adan Unna Danner Annemarie van Elburg Benny van der Vijgh Karlijn Liselotte Kooij Serguei Fetissov Nadia A. Andreani John F. Baines Astrid Dempfle Jochen Seitz Beate Herpertz-Dahlmann Andreas Karwautz 《European eating disorders review》2022,30(1):61-74
126.
The aim of this study was to determine if embryonic stem cell derived cardiomyocyte aggregates (ESdCs) can act as pacemakers in spontaneously active cardiomyocyte preparations when their connexin isoform expression is tuned toward a more sinus nodal phenotype. Using microelectrode array recordings (MEAs), we demonstrate that mouse ESdCs establish electrical coupling with spontaneously active cardiomyocyte preparations (HL-1 monolayer) and obtain pacemaker dominance. WT- and Cx43(−/−)-ESdCs comparably established intercellular coupling with cardiac host tissue (Cx43(−/−): 86% vs. WT: 91%). Although both aggregates had a 100% success rate in pacing quiescent cardiac preparations, Cx43(−/−)-ESdCs had an increased likelihood of gaining pacemaker dominance (Cx43(−/−): 40% vs. WT: 13%) in spontaneously active preparations. No differences in size, beating frequency, Vm, or differentiation were detected between WT- and Cx43(−/−)-ESdCs but the intercellular coupling resistance in Cx43(−/−)-ESdCs was significantly increased (Cx43(−/−): 1.2nS vs. WT: 14.8nS). Lack of Cx43 prolonged the time until Cx43(−/−)-ESdCs established frequency synchronization with the host tissue. It further hampered the excitation spread from the cardiomyocyte preparation into the ESdC. However rectifying excitation spread in these co-cultures could not be unequivocally identified. In summary, ESdCs can function as dominant biological pacemakers and Cx43 expression is not a prerequisite for their electrical integration. Maintenance of pacemaker dominance depends critically on the pacemaker's gap junction expression benefiting those with increased intercellular coupling resistances. Our results provide important insight into the design of biological pacemakers that will benefit the use of cardiomyocytes for cell replacement therapy. 相似文献
127.
Lene Heise Garvey Didier G. Ebo Paul‐Michel Mertes Pascale Dewachter Tomaz Garcez Peter Kopac Jos Julio Laguna Anca Mirela Chiriac Ingrid Terreehorst Susanna Voltolini Kathrin Scherer 《Allergy》2019,74(10):1872-1884
Perioperative immediate hypersensitivity reactions are rare. Subsequent allergy investigation is complicated by multiple simultaneous drug exposures, the use of drugs with potent effects and the many differential diagnoses to hypersensitivity in the perioperative setting. The approach to the investigation of these complex reactions is not standardized, and it is becoming increasingly apparent that collaboration between experts in the field of allergy/immunology/dermatology and anaesthesiology is needed to provide the best possible care for these patients. The EAACI task force behind this position paper has therefore combined the expertise of allergists, immunologists and anaesthesiologists. The aims of this position paper were to provide recommendations for the investigation of immediate‐type perioperative hypersensitivity reactions and to provide practical information that can assist clinicians in planning and carrying out investigations. 相似文献
128.
Viktoria Gredler Susanne Ebner Kathrin Schanda Markus Forstner Thomas Berger Nikolaus Romani Markus Reindl 《Clinical immunology (Orlando, Fla.)》2010,134(3):296-304
Macrophages and dendritic cells (DC) play an important role in the immunopathology of multiple sclerosis. We analyzed the impact of human myelin on monocyte-derived DC and describe their immunostimulatory capacity. Cells were grown on myelin and stimulated with LPS or a defined maturation cocktail. DC activation was analyzed by the expression of cell surface markers and the secretion of cytokines and chemokines. The immunostimulatory capacity of DC was assessed by allogeneic mixed-leukocyte reactions via proliferation. Additionally, their ability to bias T cells towards Th1, Th17 or Treg differentiation was investigated. We found that phagocytosis of myelin impaired the activation of DC, displayed by an impaired ability to stimulate allogeneic T cells, an increased production of TGF-β1 and a diminished upregulation of CCR7 but did not affect the differentiation into T helper cell subsets. We hypothesize that myelin influences DC activation and plays a pivotal role in balancing immunity and tolerance. 相似文献
129.
Doppler K Lindner A Schütz W Schütz M Bornemann A 《Brain pathology (Zurich, Switzerland)》2012,22(1):32-40
Sporadic inclusion body myositis (sIBM) contains non-necrotic myofibers that are surrounded and/or invaded by inflammatory cells. In this study we aimed to identify selective molecules that are present at this site. Myofibers of four biopsies of sIBM that were surrounded and/or invaded by inflammatory cells were microdissected, pooled and profiled by proteomic studies using mass spectrometry. Normal skeletal muscle tissue served as control. Based on the table of proteins that were detected in sIBM only, we selected nine extracellular matrix molecules and validated the results performing immunofluorescence. Seven out of nine proteins that were detected in sIBM by mass spectrometry showed different immunohistochemical results in myositis and normal controls. Of these, the small leucine-rich repeat proteins proline arginine-rich end leucine-rich repeat protein (PRELP) and biglycan were deposited precisely at myofibers surrounded and/or invaded by inflammatory cells both in sIBM and polymyositis. The basement membrane (BM) molecules merosin, perlecan, nidogen-2 and collagen IV were variably destroyed or increased at these sites. P component, which ensheathed all myofibers in normal controls, was absent from invaded myofibers. Similar to BM remodeling, the specific deposition of PRELP and biglycan may represent a mechanism to defend against immune attack. Loss of P component may affect the anchorage of the myofiber in the endomysium. 相似文献
130.
Andreas?J.?BircherEmail author Kathrin?Scherer?Hofmeier Susanne?Link Ingmar?Heijnen 《European journal of dermatology : EJD》2017,27(1):3-9
Until recently, food allergies to mammalian meats have been considered to be very rare. The observation that patients not previously exposed to the monoclonal chimeric antibody cetuximab suffered from severe anaphylaxis upon first exposure, led to the identification of galactosealpha- 1,3-galactose as a new relevant carbohydrate allergen. These patients later often suffered from anaphylactic reactions to red meat. Epidemiological data indicated that bites by the tick Amblyomma americanum in the USA, later also by Ixodes species in other continents, resulted in sensitisation to alpha-gal. On the other hand, in African patients with parasitic disorders, a high prevalence of anti-alpha-gal IgE, without clinical relevance, has been reported. In our four cases, one patient with a late onset of meat allergy had a history of a tick bite. The other three patients had symptoms from childhood or at a juvenile age. This indicates that in some patients, other ways of sensitisation may also take place. However, in patients without atopy, tick bite-induced IgE to alpha-gal may be more relevant. Diagnosis is based on a history of delayed onset of anaphylaxis. Skin tests with commercially available meat test solutions are often equivocal or negative; skin tests with raw meat and particularly pork kidney are more sensitive. Determination of specific IgE to alpha-gal is commercially available. The highest sensitivity is observed with skin and basophil activation tests with cetuximab which is, however, limited by its high costs. 相似文献