TY - JOUR A1 - Baumbach, Sebastian Felix A1 - Hörterer, Hubert A1 - Oppelt, Sonja A1 - Szeimies, Ulrike A1 - Polzer, Hans A1 - Walther, Markus T1 - Do pre-operative radiologic assessment predict postoperative outcomes in patients with insertional Achilles tendinopathy?: a retrospective database study JF - Archives of Orthopaedic and Trauma Surgery N2 - Introduction Diagnosis and treatment of insertional tendinopathy of the Achilles tendon (IAT) remains a challenge. The aim of this study was to assess the influence of pre-operative radiological pathologies on the patient-reported outcomes following open debridement of all pathologies for IAT. Materials and methods In this IRB-approved retrospective correlation and comparative study, patients with pre-operative imaging were identified from the authors’ retrospective IAT database comprising of 118 patients. All were treated by a standardized surgical treatment strategy utilizing a midline, transachillary approach and debridement of all pathologies. A total of fifteen radiologic parameters were measured on radiographs (RX) and MRI. The patient-reported outcomes were assessed using the Victorian Institute of Sport Assessment-Achilles questionnaire (VISA-A-G) and the general health questionnaire SF-12 at a minimum follow-up of 12 months. The data are presented as mean ± SD (95% CI). Results 88 patients (74.6%) with an average age of 50 ± 12 (47–52) years were included. Radiographs were available in 68 patients and MRI in 53. The mean follow-up was 3.8 ± 1.9 (3.4–4.3) years. The overall VISA-A-G was 81 ± 22 (77–86), the SF-12 PCS 54 ± 7 (52–55), and the SF-12 MCS 52 ± 9 (50–54) points. None of the assessed radiological parameters had a significant influence on the patient-reported outcome following surgical treatment for IAT. Conclusion In this retrospective correlation study, no significant association was found between preoperative radiographic and MRI radiologic parameters for IAT and postoperative patient-reported outcomes (VISA-A-G and SF-12). KW - Achilles KW - insertion KW - PROM KW - imaging KW - surgery Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-307963 SN - 1434-3916 VL - 142 IS - 11 ER - TY - JOUR A1 - Canessa, Andrea A1 - Pozzi, Nicolò G. A1 - Arnulfo, Gabriele A1 - Brumberg, Joachim A1 - Reich, Martin M. A1 - Pezzoli, Gianni A1 - Ghilardi, Maria F. A1 - Matthies, Cordula A1 - Steigerwald, Frank A1 - Volkmann, Jens A1 - Isaias, Ioannis U. T1 - Striatal Dopaminergic Innervation Regulates Subthalamic Beta-Oscillations and Cortical-Subcortical Coupling during Movements: Preliminary Evidence in Subjects with Parkinson's Disease JF - Frontiers in Human Neuroscience N2 - Activation of the basal ganglia has been shown during the preparation and execution of movement. However, the functional interaction of cortical and subcortical brain areas during movement and the relative contribution of dopaminergic striatal innervation remains unclear. We recorded local field potential (LFP) activity from the subthalamic nucleus (STN) and high-density electroencephalography (EEG) signals in four patients with Parkinson’s disease (PD) off dopaminergic medication during a multi-joint motor task performed with their dominant and non-dominant hand. Recordings were performed by means of a fully-implantable deep brain stimulation (DBS) device at 4 months after surgery. Three patients also performed a single-photon computed tomography (SPECT) with [123I]N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane (FP-CIT) to assess striatal dopaminergic innervation. Unilateral movement execution led to event-related desynchronization (ERD) followed by a rebound after movement termination event-related synchronization (ERS) of oscillatory beta activity in the STN and primary sensorimotor cortex of both hemispheres. Dopamine deficiency directly influenced movement-related beta-modulation, with greater beta-suppression in the most dopamine-depleted hemisphere for both ipsi- and contralateral hand movements. Cortical-subcortical, but not interhemispheric subcortical coherencies were modulated by movement and influenced by striatal dopaminergic innervation, being stronger in the most dopamine-depleted hemisphere. The data are consistent with a role of dopamine in shielding subcortical structures from an excessive cortical entrapment and cross-hemispheric coupling, thus allowing fine-tuning of movement. KW - beta oscillations KW - Parkinson’s disease KW - motor control KW - movement disorders KW - imaging KW - subthalamic nucleus KW - coherence analysis Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-164061 VL - 10 IS - 611 ER - TY - JOUR A1 - Drakopoulos, Antonios A1 - Decker, Michael T1 - Development and Biological Applications of Fluorescent Opioid Ligands JF - ChemPlusChem N2 - Opioid receptors (ORs) are classified among the oldest and best investigated drug targets due to their fundamental role in the treatment of pain and related disorders. ORs are divided in three conventional subtypes (μ, κ, δ) and the non‐classical nocicepetin receptor. All ORs are family A G protein‐coupled receptors (GPCRs), and are located on the cell surface. Modern biophysical methods use light to investigate physiological processes at organismal, cellular and subcellular level. Many of these methods rely on fluorescent ligands, thus highlighting their importance. This review addresses the advancements in the development of opioid fluorescent ligands and their use in biological, pharmacological and imaging applications. KW - biophysics KW - fluorescent ligands KW - imaging KW - microscopy KW - opioid receptors Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-216068 VL - 85 IS - 6 SP - 1354 EP - 1364 ER - TY - THES A1 - Griesbeck, Stefanie Ingrid T1 - A Very Positive Image of Boron: Triarylborane Chromophores for Live Cell Imaging T1 - Ein sehr positives Bild von Bor: Triarylboran Farbstoffe für Lebendzellenmikroskopie N2 - Efficient quadrupolar chromophores (A–pi–A) with triarylborane moieties as acceptors have been studied by the Marder group regarding their non‐linear optical properties and two‐photon absorption ability for many years. Within the present work, this class of dyes found applications in live‐cell imaging. Therefore, the dyes need to be water‐soluble and water‐stable in diluted aqueous solutions, which was examined in Chapter 2. Furthermore, the influence of the pi‐bridge on absorption and emission maxima, fluorescence quantum yields and especially the two-photon absorption properties of the chromophores was investigated in Chapter 3. In Chapter 4, a different strategy for the design of efficient two‐photon excited fluorescence imaging dyes was explored using dipoles (D–A) and octupoles (DA3). Finding the optimum balance between water‐stability and pi‐conjugation and, therefore, red‐shifted absorption and emission and high fluorescence quantum yields, was investigated in Chapter 5 N2 - Effiziente quadrupole Farbstoffe (A–pi–A) mit Triarylboraneinheiten als Akzeptoren wurden innerhalb der letzten Jahre von der Arbeitsgruppe Marder bezüglich ihrer nicht‐linearen optischen Eigenschaften und Zweiphotonenabsorptionsfähigkeiten untersucht. In der vorliegenden Arbeit wurde diese Farbstoffklasse zur Untersuchung lebender Zellen mittels Fluoreszenzmikroskopie angewendet. Hierzu müssen die Farbstoffe wasserlöslich und in verdünnten wässrigen Lösungen stabil sein. Dies wurde in Kapitel 2 untersucht. Außerdem wurde der Einfluss der pi‐Brücke auf das Absorptions‐ und Emissionsmaximum, die Fluoreszenzquantenausbeute und vor allem die Zweiphotonenabsorptionsfähigkeit untersucht (Kapitel 3). In Kapitel 4 wurden andere molekulare Designstrategien verfolgt um effiziente Zweiphotonenangeregtenfluoreszenzfarbstoffe zu erhalten. Dazu zählen die Strukturmotive des Dipols (D–A) und des Oktupols (DA3). Bestandteil des Kapitels 5 war die Optimierung zwischen Wasserstabilität und pi‐Konjugation und eine damit verbundene rotverschobene Absorption und Emission, sowie eine hohe Fluoreszenzquantenausbeute KW - Borane KW - Bor KW - Lumineszenz KW - Fluoreszenz KW - Zweiphotonenabsorption KW - imaging KW - luminescence KW - fluorescence KW - two-photon absorption KW - borane Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-179921 ER - TY - JOUR A1 - Hendricks, Anne A1 - Lenschow, Christina A1 - Kroiss, Matthias A1 - Buck, Andreas A1 - Kickuth, Ralph A1 - Germer, Christoph-Thomas A1 - Schlegel, Nicolas T1 - Evaluation of diagnostic efficacy for localization of parathyroid adenoma in patients with primary hyperparathyroidism undergoing repeat surgery JF - Langenbeck's Archives of Surgery N2 - Purpose Repeat surgery in patients with primary hyperparathyroidism (pHPT) is associated with an increased risk of complications and failure. This stresses the need for optimized strategies to accurately localize a parathyroid adenoma before repeat surgery is performed. However, evidence on the extent of required diagnostics for a structured approach is sparse. Methods A retrospective single-center evaluation of 28 patients with an indication for surgery due to pHPT and previous thyroid or parathyroid surgery was performed. Diagnostic workup, surgical approach, and outcome in terms of complications and successful removement of parathyroid adenoma with biochemical cure were evaluated. Results Neck ultrasound, sestamibi scintigraphy, C11-methionine PET-CT, and selective parathyroid hormone venous sampling, but not MRI imaging, effectively detected the presence of a parathyroid adenoma with high positive predictive values. Biochemical cure was revealed by normalization of calcium and parathormone levels 24-48h after surgery and was achieved in 26/28 patients (92.9%) with an overall low rate of complications. Concordant localization by at least two diagnostic modalities enabled focused surgery with success rates of 100%, whereas inconclusive localization significantly increased the rate of bilateral explorations and significantly reduced the rate of biochemical cure to 80%. Conclusion These findings suggest that two concordant diagnostic modalities are sufficient to accurately localize parathyroid adenoma before repeat surgery for pHPT. In cases of poor localization, extended diagnostic procedures are warranted to enhance surgical success rates. We suggest an algorithm for better orientation when repeat surgery is intended in patients with pHPT. KW - Primary hyperparathyroidism (pHPT) KW - preoperative localization KW - repeat surgery KW - diagnostics KW - imaging Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-267520 SN - 1435-2451 VL - 406 IS - 5 ER - TY - JOUR A1 - Krstic, Jelena A1 - Herrmann, Marietta A1 - Gadjanski, Ivana A1 - Mojsilovic, Slavko T1 - Editorial: Microenvironment-derived stem cell plasticity JF - Frontiers in Cell and Developmental Biology N2 - No abstract available. KW - plasticity KW - stem cells KW - microenvironment KW - imaging KW - extracellular vesicles (EVs) KW - oxygen tension KW - tissue regeneration KW - immunomodulation Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-197424 SN - 2296-634X VL - 5 ER - TY - JOUR A1 - Kunz, Tobias C. A1 - Götz, Ralph A1 - Sauer, Markus A1 - Rudel, Thomas T1 - Detection of chlamydia developmental forms and secreted effectors by expansion microscopy JF - Frontiers in Cellular and Infection Microbiology N2 - Expansion microscopy (ExM) is a novel tool to improve the resolution of fluorescence-based microscopy that has not yet been used to visualize intracellular pathogens. Here we show the expansion of the intracellular pathogen Chlamydia trachomatis, enabling to differentiate its two distinct forms, catabolic active reticulate bodies (RB) and infectious elementary bodies (EB), on a conventional confocal microscope. We show that ExM enables the possibility to precisely locate chlamydial effector proteins, such as CPAF or Cdu1, within and outside of the chlamydial inclusion. Thus, we claim that ExM offers the possibility to address a broad range of questions and may be useful for further research on various intracellular pathogens. KW - expansion microscopy KW - chlamydia KW - secreted effectors KW - developmental forms KW - superresolution KW - imaging Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-195716 SN - 2235-2988 VL - 9 IS - 276 ER - TY - JOUR A1 - Lapa, Constantin A1 - Lückerath, Katharina A1 - Kleinlein, Irene A1 - Monoranu, Camelia Maria A1 - Linsenmann, Thomas A1 - Kessler, Almuth F. A1 - Rudelius, Martina A1 - Kropf, Saskia A1 - Buck, Andreas K. A1 - Ernestus, Ralf-Ingo A1 - Wester, Hans-Jürgen A1 - Löhr, Mario A1 - Herrmann, Ken T1 - \(^{68}\)Ga-Pentixafor-PET/CT for Imaging of Chemokine Receptor 4 Expression in Glioblastoma JF - Theranostics N2 - Chemokine receptor-4 (CXCR4) has been reported to be overexpressed in glioblastoma (GBM) and to be associated with poor survival. This study investigated the feasibility of non-invasive CXCR4-directed imaging with positron emission tomography/computed tomography (PET/CT) using the radiolabelled chemokine receptor ligand \(^{68}\)Ga-Pentixafor. 15 patients with clinical suspicion on primary or recurrent glioblastoma (13 primary, 2 recurrent tumors) underwent \(^{68}\)Ga-Pentixafor-PET/CT for assessment of CXCR4 expression prior to surgery. O-(2-\(^{18}\)F-fluoroethyl)-L-tyrosine (\(^{18}\)F-FET) PET/CT images were available in 11/15 cases and were compared visually and semi-quantitatively (SUV\(_{max}\), SUV\(_{mean}\)). Tumor-to-background ratios (TBR) were calculated for both PET probes. \(^{68}\)Ga-Pentixafor-PET/CT results were also compared to histological CXCR4 expression on neuronavigated surgical samples. \(^{68}\)Ga-Pentixafor-PET/CT was visually positive in 13/15 cases with SUV\(_{mean}\) and SUV\(_{max}\) of 3.0±1.5 and 3.9±2.0 respectively. Respective values for \(^{18}\)F-FET were 4.4±2.0 (SUV\(_{mean}\)) and 5.3±2.3 (SUV\(_{max}\)). TBR for SUV\(_{mean}\) and SUV\(_{max}\) were higher for \(^{68}\)Ga-Pentixafor than for \(^{18}\)F-FET (SUV\(_{mean}\) 154.0±90.7 vs. 4.1±1.3; SUV\(_{max}\) 70.3±44.0 and 3.8±1.2, p<0.01), respectively. Histological analysis confirmed CXCR4 expression in tumor areas with high \(^{68}\)Ga-Pentixafor uptake; regions of the same tumor without apparent \(^{68}\)Ga-Pentixafor uptake showed no or low receptor expression. In this pilot study, \(^{68}\)Ga-Pentixafor retention has been observed in the vast majority of glioblastoma lesions and served as readout for non-invasive determination of CXCR4 expression. Given the paramount importance of the CXCR4/SDF-1 axis in tumor biology, \(^{68}\)Ga-Pentixafor-PET/CT might prove a useful tool for sensitive, non-invasive in-vivo quantification of CXCR4 as well as selection of patients who might benefit from CXCR4-directed therapy. KW - imaging KW - chemokine receptor-4 KW - glioblastoma KW - positron emission tomography/computed tomography KW - \(^{68}\)Ga-Pentixafor Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-168174 VL - 6 IS - 3 ER - TY - JOUR A1 - Li, Kunkun A1 - Prada, Juan A1 - Damineli, Daniel S. C. A1 - Liese, Anja A1 - Romeis, Tina A1 - Dandekar, Thomas A1 - Feijó, José A. A1 - Hedrich, Rainer A1 - Konrad, Kai Robert T1 - An optimized genetically encoded dual reporter for simultaneous ratio imaging of Ca\(^{2+}\) and H\(^{+}\) reveals new insights into ion signaling in plants JF - New Phytologist N2 - Whereas the role of calcium ions (Ca\(^{2+}\)) in plant signaling is well studied, the physiological significance of pH‐changes remains largely undefined. Here we developed CapHensor, an optimized dual‐reporter for simultaneous Ca\(^{2+}\) and pH ratio‐imaging and studied signaling events in pollen tubes (PTs), guard cells (GCs), and mesophyll cells (MCs). Monitoring spatio‐temporal relationships between membrane voltage, Ca\(^{2+}\)‐ and pH‐dynamics revealed interconnections previously not described. In tobacco PTs, we demonstrated Ca\(^{2+}\)‐dynamics lag behind pH‐dynamics during oscillatory growth, and pH correlates more with growth than Ca\(^{2+}\). In GCs, we demonstrated abscisic acid (ABA) to initiate stomatal closure via rapid cytosolic alkalization followed by Ca2+ elevation. Preventing the alkalization blocked GC ABA‐responses and even opened stomata in the presence of ABA, disclosing an important pH‐dependent GC signaling node. In MCs, a flg22‐induced membrane depolarization preceded Ca2+‐increases and cytosolic acidification by c. 2 min, suggesting a Ca\(^{2+}\)/pH‐independent early pathogen signaling step. Imaging Ca2+ and pH resolved similar cytosol and nuclear signals and demonstrated flg22, but not ABA and hydrogen peroxide to initiate rapid membrane voltage‐, Ca\(^{2+}\)‐ and pH‐responses. We propose close interrelation in Ca\(^{2+}\)‐ and pH‐signaling that is cell type‐ and stimulus‐specific and the pH having crucial roles in regulating PT growth and stomata movement. KW - abscisic acid (ABA) KW - calcium KW - flg22 KW - guard cells KW - imaging KW - ion signaling KW - pH KW - pollen tube Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239847 VL - 230 IS - 6 SP - 2292 EP - 2310 ER - TY - JOUR A1 - Peters, Simon A1 - Kaiser, Lena A1 - Fink, Julian A1 - Schumacher, Fabian A1 - Perschin, Veronika A1 - Schlegel, Jan A1 - Sauer, Markus A1 - Stigloher, Christian A1 - Kleuser, Burkhard A1 - Seibel, Juergen A1 - Schubert-Unkmeir, Alexandra T1 - Click-correlative light and electron microscopy (click-AT-CLEM) for imaging and tracking azido-functionalized sphingolipids in bacteria JF - Scientific Reports N2 - Sphingolipids, including ceramides, are a diverse group of structurally related lipids composed of a sphingoid base backbone coupled to a fatty acid side chain and modified terminal hydroxyl group. Recently, it has been shown that sphingolipids show antimicrobial activity against a broad range of pathogenic microorganisms. The antimicrobial mechanism, however, remains so far elusive. Here, we introduce 'click-AT-CLEM', a labeling technique for correlated light and electron microscopy (CLEM) based on the super-resolution array tomography (srAT) approach and bio-orthogonal click chemistry for imaging of azido-tagged sphingolipids to directly visualize their interaction with the model Gram-negative bacterium Neisseria meningitidis at subcellular level. We observed ultrastructural damage of bacteria and disruption of the bacterial outer membrane induced by two azido-modified sphingolipids by scanning electron microscopy and transmission electron microscopy. Click-AT-CLEM imaging and mass spectrometry clearly revealed efficient incorporation of azido-tagged sphingolipids into the outer membrane of Gram-negative bacteria as underlying cause of their antimicrobial activity. KW - antimicrobials KW - biological techniques KW - imaging KW - microbiology KW - microbiology techniques KW - microscopy Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259147 VL - 11 IS - 1 ER -