TY - JOUR A1 - Lee, Ching Hua A1 - Sutrisno, Amanda A1 - Hofmann, Tobias A1 - Helbig, Tobias A1 - Liu, Yuhan A1 - Ang, Yee Sin A1 - Ang, Lay Kee A1 - Zhang, Xiao A1 - Greiter, Martin A1 - Thomale, Ronny T1 - Imaging nodal knots in momentum space through topolectrical circuits JF - Nature Communications N2 - Knots are intricate structures that cannot be unambiguously distinguished with any single topological invariant. Momentum space knots, in particular, have been elusive due to their requisite finely tuned long-ranged hoppings. Even if constructed, probing their intricate linkages and topological "drumhead" surface states will be challenging due to the high precision needed. In this work, we overcome these practical and technical challenges with RLC circuits, transcending existing theoretical constructions which necessarily break reciprocity, by pairing nodal knots with their mirror image partners in a fully reciprocal setting. Our nodal knot circuits can be characterized with impedance measurements that resolve their drumhead states and image their 3D nodal structure. Doing so allows for reconstruction of the Seifert surface and hence knot topological invariants like the Alexander polynomial. We illustrate our approach with large-scale simulations of various nodal knots and an experiment which maps out the topological drumhead region of a Hopf-link. Topological phases with knotted configurations in momentum space have been challenging to realize. Here, Lee et al. provide a systematic design and measurement of a three-dimensional knotted nodal structure, and resolve its momentum space drumhead states via a topolectrical RLC-type circuit. KW - nodal knots KW - topolectrical circuits Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230407 VL - 11 ER - TY - INPR A1 - Braunschweig, Holger A1 - Brückner, Tobias A1 - Deißenberger, Andrea A1 - Dewhurst, Rian A1 - Gackstatter, Annika A1 - Gärtner, Annalena A1 - Hofmann, Alexander A1 - Kupfer, Thomas A1 - Prieschl, Dominic A1 - Thiess, Torsten A1 - Wang, Sunewang Rixin T1 - Reaction of Dihalodiboranes(4) with N-Heterocyclic Silylenes: Facile Construction of 1-Aryl-2-Silyl-1,2-Diboraindanes T2 - Chemistry, A European Journal N2 - Dihalodiboranes(4) react with an N-heterocyclic silylene (NHSi) to generate NHSi-adducts of 1-aryl-2-silyl-1,2-diboraindanes as confirmed by X-ray crystallography, featuring the functionalization of both B–X (X = halogen) bonds and a C–H bond under mild conditions. Coordination of a third NHSi to the proposed 1,1-diaryl- 2,2-disilyldiborane(4) intermediates, generated by a two-fold B–X insertion, may be crucial for the C–H borylation that leads to the final products. Notably, our results demonstrate the first C–H borylation with a strong B–F bond activated by silylene insertion. KW - diborane KW - boron KW - silylenes KW - CH activation KW - bond activation KW - diboraindanes KW - diboranes KW - synthetic methods KW - borylation Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-153068 N1 - This is the pre-peer reviewed version of the following article: H. Braunschweig, T. Brückner, A. Deißenberger, R. D. Dewhurst, A. Gackstatter, A. Gärtner, A. Hofmann, T. Kupfer, D. Prieschl, T. Thiess, S. R. Wang, Reaction of Dihalodiboranes(4) with a N-Heterocyclic Silylene: Facile Construction of 1-Aryl-2-Silyl-1,2-Diboraindanes, Chem. Eur. J. 2017, 23, 9491., which has been published in final form at dx.doi.org/10.1002/chem.201702377. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving ER - TY - JOUR A1 - Frey, Anna A1 - Gassenmaier, Tobias A1 - Hofmann, Ulrich A1 - Schmitt, Dominik A1 - Fette, Georg A1 - Marx, Almuth A1 - Heterich, Sabine A1 - Boivin-Jahns, Valérie A1 - Ertl, Georg A1 - Bley, Thorsten A1 - Frantz, Stefan A1 - Jahns, Roland A1 - Störk, Stefan T1 - Coagulation factor XIII activity predicts left ventricular remodelling after acute myocardial infarction JF - ESC Heart Failure N2 - Aims Acute myocardial infarction (MI) is the major cause of chronic heart failure. The activity of blood coagulation factor XIII (FXIIIa) plays an important role in rodents as a healing factor after MI, whereas its role in healing and remodelling processes in humans remains unclear. We prospectively evaluated the relevance of FXIIIa after acute MI as a potential early prognostic marker for adequate healing. Methods and results This monocentric prospective cohort study investigated cardiac remodelling in patients with ST-elevation MI and followed them up for 1 year. Serum FXIIIa was serially assessed during the first 9 days after MI and after 2, 6, and 12 months. Cardiac magnetic resonance imaging was performed within 4 days after MI (Scan 1), after 7 to 9 days (Scan 2), and after 12 months (Scan 3). The FXIII valine-to-leucine (V34L) single-nucleotide polymorphism rs5985 was genotyped. One hundred forty-six patients were investigated (mean age 58 ± 11 years, 13% women). Median FXIIIa was 118 % (quartiles, 102–132%) and dropped to a trough on the second day after MI: 109%(98–109%; P < 0.001). FXIIIa recovered slowly over time, reaching the baseline level after 2 to 6 months and surpassed baseline levels only after 12 months: 124 % (110–142%). The development of FXIIIa after MI was independent of the genotype. FXIIIa on Day 2 was strongly and inversely associated with the relative size of MI in Scan 1 (Spearman’s ρ = –0.31; P = 0.01) and Scan 3 (ρ = –0.39; P < 0.01) and positively associated with left ventricular ejection fraction: ρ = 0.32 (P < 0.01) and ρ = 0.24 (P = 0.04), respectively. Conclusions FXIII activity after MI is highly dynamic, exhibiting a significant decline in the early healing period, with reconstitution 6 months later. Depressed FXIIIa early after MI predicted a greater size of MI and lower left ventricular ejection fraction after 1 year. The clinical relevance of these findings awaits to be tested in a randomized trial. KW - blood coagulation factor XIII KW - ST-elevation myocardial infarction KW - healing and remodelling processes KW - cardiac magnetic resonance imaging Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236013 VL - 7 IS - 5 ER - TY - JOUR A1 - Wilde, Anne-Christin Beatrice A1 - Lieb, Charlotte A1 - Leicht, Elise A1 - Greverath, Lena Maria A1 - Steinhagen, Lara Marleen A1 - Wald de Chamorro, Nina A1 - Petersen, Jörg A1 - Hofmann, Wolf Peter A1 - Hinrichsen, Holger A1 - Heyne, Renate A1 - Berg, Thomas A1 - Naumann, Uwe A1 - Schwenzer, Jeannette A1 - Vermehren, Johannes A1 - Geier, Andreas A1 - Tacke, Frank A1 - Müller, Tobias T1 - Real-world clinical management of patients with primary biliary cholangitis — a retrospective multicenter study from Germany JF - Journal of Clinical Medicine N2 - Background: Clinical practice guidelines for patients with primary biliary cholangitis (PBC) have been recently revised and implemented for well-established response criteria to standard first-line ursodeoxycholic acid (UDCA) therapy at 12 months after treatment initiation for the early identification of high-risk patients with inadequate treatment responses who may require treatment modification. However, there are only very limited data concerning the real-world clinical management of patients with PBC in Germany. Objective: The aim of this retrospective multicenter study was to evaluate response rates to standard first-line UDCA therapy and subsequent Second-line treatment regimens in a large cohort of well-characterized patients with PBC from 10 independent hepatological referral centers in Germany prior to the introduction of obeticholic acid as a licensed second-line treatment option. Methods: Diagnostic confirmation of PBC, standard first-line UDCA treatment regimens and response rates at 12 months according to Paris-I, Paris-II, and Barcelona criteria, the follow-up cut-off alkaline phosphatase (ALP) ≤ 1.67 × upper limit of normal (ULN) and the normalization of bilirubin (bilirubin ≤ 1 × ULN) were retrospectively examined between June 1986 and March 2017. The management and hitherto applied second-line treatment regimens in patients with an inadequate response to UDCA and subsequent response rates at 12 months were also evaluated. Results: Overall, 480 PBC patients were included in this study. The median UDCA dosage was 13.2 mg UDCA/kg bodyweight (BW)/d. Adequate UDCA treatment response rates according to Paris-I, Paris-II, and Barcelona criteria were observed in 91, 71.3, and 61.3% of patients, respectively. In 83.8% of patients, ALP ≤ 1.67 × ULN were achieved. A total of 116 patients (24.2%) showed an inadequate response to UDCA according to at least one criterion. The diverse second-line treatment regimens applied led to significantly higher response rates according to Paris-II (35 vs. 60%, p = 0.005), Barcelona (13 vs. 34%, p = 0.0005), ALP ≤ 1.67 × ULN and bilirubin ≤ 1 × ULN (52.1 vs. 75%, p = 0.002). The addition of bezafibrates appeared to induce the strongest beneficial effect in this cohort (Paris II: 24 vs. 74%, p = 0.004; Barcelona: 50 vs. 84%, p = 0.046; ALP < 1.67 × ULN and bilirubin ≤ 1 × ULN: 33 vs. 86%, p = 0.001). Conclusion: Our large retrospective multicenter study confirms high response rates following UDCA first-line standard treatment in patients with PBC and highlights the need for close monitoring and early treatment modification in high-risk patients with an insufficient response to UDCA since early treatment modification significantly increases subsequent response rates of these patients. KW - primary biliary cholangitis KW - autoantibodies KW - ursodeoxycholic acid KW - treatment response KW - second line therapy Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234003 SN - 2077-0383 VL - 10 IS - 5 ER - TY - JOUR A1 - Boch, Tobias A1 - Spiess, Birgit A1 - Heinz, Werner A1 - Cornely, Oliver A. A1 - Schwerdtfeger, Rainer A1 - Hahn, Joachim A1 - Krause, Stefan W. A1 - Duerken, Matthias A1 - Bertz, Hartmut A1 - Reuter, Stefan A1 - Kiehl, Michael A1 - Claus, Bernd A1 - Deckert, Peter Markus A1 - Hofmann, Wolf‐Karsten A1 - Buchheidt, Dieter A1 - Reinwald, Mark T1 - Aspergillus specific nested PCR from the site of infection is superior to testing concurrent blood samples in immunocompromised patients with suspected invasive aspergillosis JF - Mycoses N2 - Invasive aspergillosis (IA) is a severe complication in immunocompromised patients. Early diagnosis is crucial to decrease its high mortality, yet the diagnostic gold standard (histopathology and culture) is time‐consuming and cannot offer early confirmation of IA. Detection of IA by polymerase chain reaction (PCR) shows promising potential. Various studies have analysed its diagnostic performance in different clinical settings, especially addressing optimal specimen selection. However, direct comparison of different types of specimens in individual patients though essential, is rarely reported. We systematically assessed the diagnostic performance of an Aspergillus‐specific nested PCR by investigating specimens from the site of infection and comparing it with concurrent blood samples in individual patients (pts) with IA. In a retrospective multicenter analysis PCR was performed on clinical specimens (n = 138) of immunocompromised high‐risk pts (n = 133) from the site of infection together with concurrent blood samples. 38 pts were classified as proven/probable, 67 as possible and 28 as no IA according to 2008 European Organization for Research and Treatment of Cancer/Mycoses Study Group consensus definitions. A considerably superior performance of PCR from the site of infection was observed particularly in pts during antifungal prophylaxis (AFP)/antifungal therapy (AFT). Besides a specificity of 85%, sensitivity varied markedly in BAL (64%), CSF (100%), tissue samples (67%) as opposed to concurrent blood samples (8%). Our results further emphasise the need for investigating clinical samples from the site of infection in case of suspected IA to further establish or rule out the diagnosis. KW - antifungal KW - aspergillosis KW - BAL KW - blood KW - cerebrospinal fluid KW - comparison KW - PCR KW - Aspergillus Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-214065 VL - 62 IS - 11 SP - 1035 EP - 1042 ER - TY - JOUR A1 - Bittner, Stefan A1 - Bobak, Nicole A1 - Hofmann, Majella-Sophie A1 - Schuhmann, Michael K. A1 - Ruck, Tobias A1 - Göbel, Kerstin A1 - Brück, Wolfgang A1 - Wiendl, Heinz A1 - Meuth, Sven G. T1 - Murine K\(_{2P}\)5.1 Deficiency Has No Impact on Autoimmune Neuroinflammation due to Compensatory K\(_{2P}\)3.1-and K\(_{V}\)1.3-Dependent Mechanisms JF - International Journal of Molecular Sciences N2 - Lymphocytes express potassium channels that regulate physiological cell functions, such as activation, proliferation and migration. Expression levels of K\(_{2P}\)5.1(TASK2; KCNK5) channels belonging to the family of two-pore domain potassium channels have previously been correlated to the activity of autoreactive T lymphocytes in patients with multiple sclerosis and rheumatoid arthritis. In humans, K\(_{2P}\)5.1 channels are upregulated upon T cell stimulation and influence T cell effector functions. However, a further clinical translation of targeting K\(_{2P}\)5.1 is currently hampered by a lack of highly selective inhibitors, making it necessary to evaluate the impact of KCNK5 in established preclinical animal disease models. We here demonstrate that K\(_{2P}\)5.1 knockout (K\(_{2P}\)5.1\(^{-/-}\) mice display no significant alterations concerning T cell cytokine production, proliferation rates, surface marker molecules or signaling pathways. In an experimental model of autoimmune neuroinflammation, K\(_{2P}\)5.1\(^{-/-}\) mice show a comparable disease course to wild-type animals and no major changes in the peripheral immune system or CNS compartment. A compensatory upregulation of the potassium channels K\(_{2P}\)3.1 and K\(_{V}\)1.3 seems to counterbalance the deletion of K\(_{2P}\)5.1. As an alternative model mimicking autoimmune neuroinflammation, experimental autoimmune encephalomyelitis in the common marmoset has been proposed, especially for testing the efficacy of new potential drugs. Initial experiments show that K\(_{2P}\)5.1 is functionally expressed on marmoset T lymphocytes, opening up the possibility for assessing future K\(_{2P}\)5.1-targeting drugs. KW - domain potassium channels KW - volume regulation KW - multiple-sclerosis KW - potassium channels KW - multiple sclerosis KW - ion channels KW - K+ channel KW - T lymphocytes KW - up-regulation KW - TASK2 KW - K2P channels KW - B cells KW - ph KW - K\(_{2P}\)5.1 KW - KCNK5 KW - autoimmune neuroinflammation KW - EAE Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-151454 VL - 16 SP - 16880 EP - 16896 ER - TY - JOUR A1 - Traub, Jan A1 - Grondey, Katja A1 - Gassenmaier, Tobias A1 - Schmitt, Dominik A1 - Fette, Georg A1 - Frantz, Stefan A1 - Boivin-Jahns, Valérie A1 - Jahns, Roland A1 - Störk, Stefan A1 - Stoll, Guido A1 - Reiter, Theresa A1 - Hofmann, Ulrich A1 - Weber, Martin S. A1 - Frey, Anna T1 - Sustained increase in serum glial fibrillary acidic protein after first ST-elevation myocardial infarction JF - International Journal of Molecular Sciences N2 - Acute ischemic cardiac injury predisposes one to cognitive impairment, dementia, and depression. Pathophysiologically, recent positron emission tomography data suggest astroglial activation after experimental myocardial infarction (MI). We analyzed peripheral surrogate markers of glial (and neuronal) damage serially within 12 months after the first ST-elevation MI (STEMI). Serum levels of glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) were quantified using ultra-sensitive molecular immunoassays. Sufficient biomaterial was available from 45 STEMI patients (aged 28 to 78 years, median 56 years, 11% female). The median (quartiles) of GFAP was 63.8 (47.0, 89.9) pg/mL and of NfL 10.6 (7.2, 14.8) pg/mL at study entry 0–4 days after STEMI. GFAP after STEMI increased in the first 3 months, with a median change of +7.8 (0.4, 19.4) pg/mL (p = 0.007). It remained elevated without further relevant increases after 6 months (+11.7 (0.6, 23.5) pg/mL; p = 0.015), and 12 months (+10.3 (1.5, 22.7) pg/mL; p = 0.010) compared to the baseline. Larger relative infarction size was associated with a higher increase in GFAP (ρ = 0.41; p = 0.009). In contrast, NfL remained unaltered in the course of one year. Our findings support the idea of central nervous system involvement after MI, with GFAP as a potential peripheral biomarker of chronic glial damage as one pathophysiologic pathway. KW - myocardial infarction KW - STEMI KW - glial fibrillary acidic protein KW - GFAP KW - neurofilament light chain KW - NfL KW - glial damage KW - cardiac magnetic resonance imaging KW - MRI KW - infarction size Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-288261 SN - 1422-0067 VL - 23 IS - 18 ER - TY - JOUR A1 - Delgobo, Murilo A1 - Heinrichs, Margarete A1 - Hapke, Nils A1 - Ashour, DiyaaElDin A1 - Appel, Marc A1 - Srivastava, Mugdha A1 - Heckel, Tobias A1 - Spyridopoulos, Ioakim A1 - Hofmann, Ulrich A1 - Frantz, Stefan A1 - Ramos, Gustavo Campos T1 - Terminally Differentiated CD4\(^+\) T Cells Promote Myocardial Inflammaging JF - Frontiers in Immunology N2 - The cardiovascular and immune systems undergo profound and intertwined alterations with aging. Recent studies have reported that an accumulation of memory and terminally differentiated T cells in elderly subjects can fuel myocardial aging and boost the progression of heart diseases. Nevertheless, it remains unclear whether the immunological senescence profile is sufficient to cause age-related cardiac deterioration or merely acts as an amplifier of previous tissue-intrinsic damage. Herein, we sought to decompose the causality in this cardio-immune crosstalk by studying young mice harboring a senescent-like expanded CD4\(^+\) T cell compartment. Thus, immunodeficient NSG-DR1 mice expressing HLA-DRB1*01:01 were transplanted with human CD4\(^+\) T cells purified from matching donors that rapidly engrafted and expanded in the recipients without causing xenograft reactions. In the donor subjects, the CD4\(^+\) T cell compartment was primarily composed of naïve cells defined as CCR7\(^+\)CD45RO\(^-\). However, when transplanted into young lymphocyte-deficient mice, CD4\(^+\) T cells underwent homeostatic expansion, upregulated expression of PD-1 receptor and strongly shifted towards effector/memory (CCR7\(^-\) CD45RO\(^+\)) and terminally-differentiated phenotypes (CCR7\(^-\)CD45RO\(^-\)), as typically seen in elderly. Differentiated CD4\(^+\) T cells also infiltrated the myocardium of recipient mice at comparable levels to what is observed during physiological aging. In addition, young mice harboring an expanded CD4\(^+\) T cell compartment showed increased numbers of infiltrating monocytes, macrophages and dendritic cells in the heart. Bulk mRNA sequencing analyses further confirmed that expanding T-cells promote myocardial inflammaging, marked by a distinct age-related transcriptomic signature. Altogether, these data indicate that exaggerated CD4\(^+\) T-cell expansion and differentiation, a hallmark of the aging immune system, is sufficient to promote myocardial alterations compatible with inflammaging in juvenile healthy mice. KW - CD4+ T-cells KW - myocardial aging KW - inflammaging KW - NSG animals KW - immunosenescence KW - lymphocytes Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-229612 SN - 1664-3224 VL - 12 ER - TY - JOUR A1 - Schreiber, Laura M. A1 - Lohr, David A1 - Baltes, Steffen A1 - Vogel, Ulrich A1 - Elabyad, Ibrahim A. A1 - Bille, Maya A1 - Reiter, Theresa A1 - Kosmala, Aleksander A1 - Gassenmaier, Tobias A1 - Stefanescu, Maria R. A1 - Kollmann, Alena A1 - Aures, Julia A1 - Schnitter, Florian A1 - Pali, Mihaela A1 - Ueda, Yuichiro A1 - Williams, Tatiana A1 - Christa, Martin A1 - Hofmann, Ulrich A1 - Bauer, Wolfgang A1 - Gerull, Brenda A1 - Zernecke, Alma A1 - Ergün, Süleyman A1 - Terekhov, Maxim T1 - Ultra-high field cardiac MRI in large animals and humans for translational cardiovascular research JF - Frontiers in Cardiovascular Medicine N2 - A key step in translational cardiovascular research is the use of large animal models to better understand normal and abnormal physiology, to test drugs or interventions, or to perform studies which would be considered unethical in human subjects. Ultrahigh field magnetic resonance imaging (UHF-MRI) at 7 T field strength is becoming increasingly available for imaging of the heart and, when compared to clinically established field strengths, promises better image quality and image information content, more precise functional analysis, potentially new image contrasts, and as all in-vivo imaging techniques, a reduction of the number of animals per study because of the possibility to scan every animal repeatedly. We present here a solution to the dual use problem of whole-body UHF-MRI systems, which are typically installed in clinical environments, to both UHF-MRI in large animals and humans. Moreover, we provide evidence that in such a research infrastructure UHF-MRI, and ideally combined with a standard small-bore UHF-MRI system, can contribute to a variety of spatial scales in translational cardiovascular research: from cardiac organoids, Zebra fish and rodent hearts to large animal models such as pigs and humans. We present pilot data from serial CINE, late gadolinium enhancement, and susceptibility weighted UHF-MRI in a myocardial infarction model over eight weeks. In 14 pigs which were delivered from a breeding facility in a national SARS-CoV-2 hotspot, we found no infection in the incoming pigs. Human scanning using CINE and phase contrast flow measurements provided good image quality of the left and right ventricle. Agreement of functional analysis between CINE and phase contrast MRI was excellent. MRI in arrested hearts or excised vascular tissue for MRI-based histologic imaging, structural imaging of myofiber and vascular smooth muscle cell architecture using high-resolution diffusion tensor imaging, and UHF-MRI for monitoring free radicals as a surrogate for MRI of reactive oxygen species in studies of oxidative stress are demonstrated. We conclude that UHF-MRI has the potential to become an important precision imaging modality in translational cardiovascular research. KW - ultrahigh-field MRI KW - large animal models KW - translational research KW - research infrastructure KW - heart KW - organoid KW - pig KW - cardiovascular MRI Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-317398 SN - 2297-055X VL - 10 ER -