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Evrard R, Manon J, Rafferty C, Fieve L, Cornu O, Kirchgesner T, Lecouvet FE, Schubert T, Lengele B. Vascular study of decellularized porcine long bones: Characterization of a tissue engineering model. Bone 2024; 182:117073. [PMID: 38493932 DOI: 10.1016/j.bone.2024.117073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 03/19/2024]
Abstract
INTRODUCTION Massive bone allografts enable the reconstruction of critical bone defects in numerous conditions (e.g. tumoral, infection or trauma). Unfortunately, their biological integration remains insufficient and the reconstruction may suffer from several postoperative complications. Perfusion-decellularization emerges as a tissue engineering potential solution to enhance osseointegration. Therefore, an intrinsic vascular study of this novel tissue engineering tool becomes essential to understand its efficacy and applicability. MATERIAL AND METHODS 32 porcine long bones (humeri and femurs) were used to assess the quality of their vascular network prior and after undergoing a perfusion-decellularization protocol. 12 paired bones were used to assess the vascular matrix prior (N = 6) and after our protocol (N = 6) by immunohistochemistry. Collagen IV, Von Willebrand factor and CD31 were targeted then quantified. The medullary macroscopic vascular network was evaluated with 12 bones: 6 were decellularized and the other 6 were, as control, not treated. All 12 underwent a contrast-agent injection through the nutrient artery prior an angio CT-scan acquisition. The images were processed and the length of medullary vessels filled with contrast agent were measured on angiographic cT images obtained in control and decellularized bones by 4 independent observers to evaluate the vascular network preservation. The microscopic cortical vascular network was evaluated on 8 bones: 4 control and 4 decellularized. After injection of gelatinous fluorochrome mixture (calcein green), non-decalcified fluoroscopic microscopy was performed in order to assess the perfusion quality of cortical vascular lacunae. RESULTS The continuity of the microscopic vascular network was assessed with Collagen IV immunohistochemistry (p-value = 0.805) while the decellularization quality was observed through CD31 and Von Willebrand factor immunohistochemistry (p-values <0.001). The macroscopic vascular network was severely impaired after perfusion-decellularization; nutrient arteries were still patent but the amount of medullary vascular channels measured was significantly higher in the control group compared to the decellularized group (p-value <0.001). On average, the observers show good agreement on these results, except in the decellularized group where more inter-observer discrepancies were observed. The microscopic vascular network was observed with green fluoroscopic signal in almost every canals and lacunae of the bone cortices, in three different bone locations (proximal metaphysis, diaphysis and distal metaphysis). CONCLUSION Despite the aggressiveness of the decellularization protocol on medullary vessels, total porcine long bones decellularized by perfusion retain an acellular cortical microvascular network. By injection through the intact nutrient arteries, this latter vascular network can still be used as a total bone infusion access for bone tissue engineering in order to enhance massive bone allografts prior implantation.
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Affiliation(s)
- R Evrard
- Institut de Recherche Expérimentale et Clinique, Neuro Musculo-Skeletal Lab, Université Catholique de Louvain (UCLouvain), Avenue E. Mounier, 52-B1.52.04, 1200 Bruxelles, Belgium; Service de Chirurgie Orthopédique et Traumatologique, Cliniques Universitaires Saint-Luc, UCLouvain, Avenue Hippocrate 10, 1200 Bruxelles, Belgium.
| | - J Manon
- Institut de Recherche Expérimentale et Clinique, Neuro Musculo-Skeletal Lab, Université Catholique de Louvain (UCLouvain), Avenue E. Mounier, 52-B1.52.04, 1200 Bruxelles, Belgium; Service de Chirurgie Orthopédique et Traumatologique, Cliniques Universitaires Saint-Luc, UCLouvain, Avenue Hippocrate 10, 1200 Bruxelles, Belgium
| | - C Rafferty
- Institut de Recherche Expérimentale et Clinique, Pôle Morphologie, UCLouvain, Avenue E. Mounier, 52-B1.52.04, 1200 Bruxelles, Belgium
| | - L Fieve
- Institut de Recherche Expérimentale et Clinique, Pôle Morphologie, UCLouvain, Avenue E. Mounier, 52-B1.52.04, 1200 Bruxelles, Belgium
| | - O Cornu
- Institut de Recherche Expérimentale et Clinique, Neuro Musculo-Skeletal Lab, Université Catholique de Louvain (UCLouvain), Avenue E. Mounier, 52-B1.52.04, 1200 Bruxelles, Belgium; Service de Chirurgie Orthopédique et Traumatologique, Cliniques Universitaires Saint-Luc, UCLouvain, Avenue Hippocrate 10, 1200 Bruxelles, Belgium; Unité de Thérapie Tissulaire et Cellulaire de l'Appareil Locomoteur, Cliniques Universitaires Saint-Luc, Avenue Hippocrate 10, 1200 Bruxelles, Belgium
| | - T Kirchgesner
- Département d'Imagerie Médicale, Institut de Recherche Expérimentale et Clinique (Pôle IMAG), Cliniques Universitaires Saint-Luc, UCLouvain, Avenue Hippocrate 10, 1200 Bruxelles, Belgium
| | - F E Lecouvet
- Département d'Imagerie Médicale, Institut de Recherche Expérimentale et Clinique (Pôle IMAG), Cliniques Universitaires Saint-Luc, UCLouvain, Avenue Hippocrate 10, 1200 Bruxelles, Belgium
| | - T Schubert
- Institut de Recherche Expérimentale et Clinique, Neuro Musculo-Skeletal Lab, Université Catholique de Louvain (UCLouvain), Avenue E. Mounier, 52-B1.52.04, 1200 Bruxelles, Belgium; Service de Chirurgie Orthopédique et Traumatologique, Cliniques Universitaires Saint-Luc, UCLouvain, Avenue Hippocrate 10, 1200 Bruxelles, Belgium; Unité de Thérapie Tissulaire et Cellulaire de l'Appareil Locomoteur, Cliniques Universitaires Saint-Luc, Avenue Hippocrate 10, 1200 Bruxelles, Belgium
| | - B Lengele
- Institut de Recherche Expérimentale et Clinique, Pôle Morphologie, UCLouvain, Avenue E. Mounier, 52-B1.52.04, 1200 Bruxelles, Belgium; Service de Chirurgie Plastique, Reconstructrice et Esthétique, Cliniques Universitaires Saint-Luc, UCLouvain, Avenue Hippocrate 10, 1200 Bruxelles, Belgium
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Chang L, Ran Y, Yang M, Auferkorte O, Butz E, Hüser L, Haverkamp S, Euler T, Schubert T. Spike desensitisation as a mechanism for high-contrast selectivity in retinal ganglion cells. Front Cell Neurosci 2024; 17:1337768. [PMID: 38269116 PMCID: PMC10806099 DOI: 10.3389/fncel.2023.1337768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 12/19/2023] [Indexed: 01/26/2024] Open
Abstract
In the vertebrate retina, several dozens of parallel channels relay information about the visual world to the brain. These channels are represented by the different types of retinal ganglion cells (RGCs), whose responses are rendered selective for distinct sets of visual features by various mechanisms. These mechanisms can be roughly grouped into synaptic interactions and cell-intrinsic mechanisms, with the latter including dendritic morphology as well as ion channel complement and distribution. Here, we investigate how strongly ion channel complement can shape RGC output by comparing two mouse RGC types, the well-described ON alpha cell and a little-studied ON cell that is EGFP-labelled in the Igfbp5 mouse line and displays an unusual selectivity for stimuli with high contrast. Using patch-clamp recordings and computational modelling, we show that a higher activation threshold and a pronounced slow inactivation of the voltage-gated Na+ channels contribute to the distinct contrast tuning and transient responses in ON Igfbp5 RGCs, respectively. In contrast, such a mechanism could not be observed in ON alpha cells. This study provides an example for the powerful role that the last stage of retinal processing can play in shaping RGC responses.
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Affiliation(s)
- Le Chang
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
- Key Laboratory of Primate Neurobiology, Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Yanli Ran
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province, and Institute of Physiology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, China
| | - Mingpo Yang
- Key Laboratory of Primate Neurobiology, Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | | | - Elisabeth Butz
- Max-Planck-Institute for Brain Research, Frankfurt am Main, Germany
| | - Laura Hüser
- Max-Planck-Institute for Brain Research, Frankfurt am Main, Germany
| | - Silke Haverkamp
- Max-Planck-Institute for Brain Research, Frankfurt am Main, Germany
- Department of Computational Neuroethology, Max Planck Institute for Neurobiology of Behavior – Caesar, Bonn, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
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Vlasits A, Korympidou MM, Strauss S, Schubert T, Franke K, Berens P, Euler T. Invited Session III: Diversity in chromatic processing across the animal kingdom: Color processing in the mouse retina. J Vis 2023; 23:14. [PMID: 38109634 DOI: 10.1167/jov.23.15.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2023] Open
Abstract
Across species, specialized retinal circuits allow animals to extract visual information from their environments. How retinal circuits extract relevant visual information is a major area of inquiry. In the mouse retina, cone photoreceptors possess a gradient of opsin expression leading to uneven detection of colors across visual space. However, at the output of the retina, ganglion cells' color preferences deviate from this gradient, suggesting that circuits in the retina may alter the color information before sending it to the brain. We explored how circuits in the retina shape chromatic information, focusing on the retina's interneurons, amacrine cells and bipolar cells. We found that inhibitory amacrine cells rebalance color preferences, leading to diverse color selectivity throughout retinal space. Since amacrine cells vary widely across species, these cells are poised to tune the chromatic information sent to the brain to each species' environmental niche.
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Affiliation(s)
- Anna Vlasits
- Department of Neurobiology, Northwestern University
| | | | - Sarah Strauss
- Institute for Ophthalmic Research, University of Tuebingen
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tuebingen
| | | | - Philipp Berens
- Tuebingen AI Center, Institute for Ophthalmic Research, University of Tuebingen
| | - Thomas Euler
- Institute for Ophthalmic Research, Werner Reichardt Centre for Integrative Neuroscience, University of Tuebingen
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Qiu Y, Klindt DA, Szatko KP, Gonschorek D, Hoefling L, Schubert T, Busse L, Bethge M, Euler T. Efficient coding of natural scenes improves neural system identification. PLoS Comput Biol 2023; 19:e1011037. [PMID: 37093861 PMCID: PMC10159360 DOI: 10.1371/journal.pcbi.1011037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 05/04/2023] [Accepted: 03/20/2023] [Indexed: 04/25/2023] Open
Abstract
Neural system identification aims at learning the response function of neurons to arbitrary stimuli using experimentally recorded data, but typically does not leverage normative principles such as efficient coding of natural environments. Visual systems, however, have evolved to efficiently process input from the natural environment. Here, we present a normative network regularization for system identification models by incorporating, as a regularizer, the efficient coding hypothesis, which states that neural response properties of sensory representations are strongly shaped by the need to preserve most of the stimulus information with limited resources. Using this approach, we explored if a system identification model can be improved by sharing its convolutional filters with those of an autoencoder which aims to efficiently encode natural stimuli. To this end, we built a hybrid model to predict the responses of retinal neurons to noise stimuli. This approach did not only yield a higher performance than the "stand-alone" system identification model, it also produced more biologically plausible filters, meaning that they more closely resembled neural representation in early visual systems. We found these results applied to retinal responses to different artificial stimuli and across model architectures. Moreover, our normatively regularized model performed particularly well in predicting responses of direction-of-motion sensitive retinal neurons. The benefit of natural scene statistics became marginal, however, for predicting the responses to natural movies. In summary, our results indicate that efficiently encoding environmental inputs can improve system identification models, at least for noise stimuli, and point to the benefit of probing the visual system with naturalistic stimuli.
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Affiliation(s)
- Yongrong Qiu
- Institute for Ophthalmic Research, U Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), U Tübingen, Tübingen, Germany
- Graduate Training Centre of Neuroscience (GTC), International Max Planck Research School, U Tübingen, Tübingen, Germany
| | - David A Klindt
- Institute for Ophthalmic Research, U Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), U Tübingen, Tübingen, Germany
- Department of Mathematical Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Klaudia P Szatko
- Institute for Ophthalmic Research, U Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), U Tübingen, Tübingen, Germany
- Graduate Training Centre of Neuroscience (GTC), International Max Planck Research School, U Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience, Tübingen, Germany
| | - Dominic Gonschorek
- Institute for Ophthalmic Research, U Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), U Tübingen, Tübingen, Germany
- Research Training Group 2381, U Tübingen, Tübingen, Germany
| | - Larissa Hoefling
- Institute for Ophthalmic Research, U Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), U Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience, Tübingen, Germany
| | - Timm Schubert
- Institute for Ophthalmic Research, U Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), U Tübingen, Tübingen, Germany
| | - Laura Busse
- Division of Neurobiology, Faculty of Biology, LMU Munich, Planegg-Martinsried, Germany
- Bernstein Center for Computational Neuroscience, Planegg-Martinsried, Germany
| | - Matthias Bethge
- Centre for Integrative Neuroscience (CIN), U Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience, Tübingen, Germany
- Institute for Theoretical Physics, U Tübingen, Tübingen, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, U Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), U Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience, Tübingen, Germany
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5
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Boehmer AA, Schubert T, Zezyk C, Kaess B, Ehrlich JR. ARNI effects in HFrEF. Risk reduction beyond LVEF. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
The imbalance of cardiac autonomic nervous system function plays an important role in heart failure associated mortality. ARNI has demonstrated a paramount effect in reducing risk of death and hospitalization for worsening of heart failure. However, its exact mechanism of action remains only partly understood. We sought to prospectively compare heart rate variability as a noninvasive measure of cardiac autonomic nervous system function.
Methods
The study design was prospective sequential observational. Patients served as their own internal control. Patients with heart failure with reduced ejection fraction (HFrEF) receiving optimal medical therapy who were scheduled for a switch to ARNI therapy underwent echocardiography and a standardized 30-minute 12-lead Holter ECG recording before starting ARNI therapy. A monitoring of the parameters was performed 3 months after the start of therapy. Physicians were instructed to increase ARNI dose to the highest tolerated or maximum dose. Besides left ventricular ejection fraction (LVEF) we assessed heart rate (HR), standard deviation of normal-to-normal intervals (SDNN) and mean square of differences between consecutive R-R intervals (RMSSD).
Results
We recruited 55 patients and baseline characteristics were as follows: age 65±12 years, male sex 78%, NT-proBNP 4989±809 pg/ml, LVEF 28±6%, HR 75±9 bpm, SDNN 43±2 ms, RMSSD 19±2 ms. All patients received beta-blocker therapy and the dosage was similar at baseline and follow-up. After 3 months of ARNI therapy, heart rate showed a significant reduction of 7% (74±14 bpm vs. 69±11 min, P=0.005). SDNN increased by 49% (43±2 ms vs. 64±4 ms, P<0.001) and RMSSD by 42% (19±2 ms vs. 27±3 ms, P=0.01). These results were accompanied by increased LVEF (28±6% vs. 38±10%, P<0.001) and reduced plasma NT-proBNP levels (4989±809 pg/ml vs. 2602±87 pg/ml, P<0.04). NYHA Class of affected patients changed from III to II.
Conclusion
After changing from ACE/AT1-I to ARNI, significant improvement of autonomic cardiac nervous system function could be observed. ARNI apparently activates the parasympathetic nervous system as suggested by decreased HR and increased SDNN and RMSSD. Therefore, part of its cardioprotective and beneficial effects may relate to the restoration of autonomic cardiac nervous system function. Potential beneficial effects regarding incidence of sudden cardiac arrest may relate to these observations.
Funding Acknowledgement
Type of funding sources: None.
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Affiliation(s)
- A A Boehmer
- St. Josefs-Hospital Wiesbaden , Wiesbaden , Germany
| | - T Schubert
- St. Josefs-Hospital Wiesbaden , Wiesbaden , Germany
| | - C Zezyk
- St. Josefs-Hospital Wiesbaden , Wiesbaden , Germany
| | - B Kaess
- St. Josefs-Hospital Wiesbaden , Wiesbaden , Germany
| | - J R Ehrlich
- St. Josefs-Hospital Wiesbaden , Wiesbaden , Germany
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6
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Strauss S, Korympidou MM, Ran Y, Franke K, Schubert T, Baden T, Berens P, Euler T, Vlasits AL. Center-surround interactions underlie bipolar cell motion sensitivity in the mouse retina. Nat Commun 2022; 13:5574. [PMID: 36163124 PMCID: PMC9513071 DOI: 10.1038/s41467-022-32762-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 08/16/2022] [Indexed: 11/09/2022] Open
Abstract
Motion sensing is a critical aspect of vision. We studied the representation of motion in mouse retinal bipolar cells and found that some bipolar cells are radially direction selective, preferring the origin of small object motion trajectories. Using a glutamate sensor, we directly observed bipolar cells synaptic output and found that there are radial direction selective and non-selective bipolar cell types, the majority being selective, and that radial direction selectivity relies on properties of the center-surround receptive field. We used these bipolar cell receptive fields along with connectomics to design biophysical models of downstream cells. The models and additional experiments demonstrated that bipolar cells pass radial direction selective excitation to starburst amacrine cells, which contributes to their directional tuning. As bipolar cells provide excitation to most amacrine and ganglion cells, their radial direction selectivity may contribute to motion processing throughout the visual system.
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Affiliation(s)
- Sarah Strauss
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
- Tübingen AI Center, University of Tübingen, Tübingen, Germany
| | - Maria M Korympidou
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Yanli Ran
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Katrin Franke
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Tom Baden
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- School of Life Sciences, University of Sussex, Brighton, UK
| | - Philipp Berens
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
- Tübingen AI Center, University of Tübingen, Tübingen, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.
| | - Anna L Vlasits
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.
- Department of Neurobiology, Northwestern University, Evanston, IL, USA.
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Hoffmann F, Bolz S, Junger K, Klose F, Schubert T, Woerz F, Boldt K, Ueffing M, Beyer T. TTC30A and TTC30B Redundancy Protects IFT Complex B Integrity and Its Pivotal Role in Ciliogenesis. Genes (Basel) 2022; 13:genes13071191. [PMID: 35885974 PMCID: PMC9319246 DOI: 10.3390/genes13071191] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/07/2022] [Accepted: 06/29/2022] [Indexed: 12/02/2022] Open
Abstract
Intraflagellar transport (IFT) is a microtubule-based system that supports the assembly and maintenance of cilia. The dysfunction of IFT leads to ciliopathies of variable severity. Two of the IFT-B components are the paralogue proteins TTC30A and TTC30B. To investigate whether these proteins constitute redundant functions, CRISPR/Cas9 was used to generate single TTC30A or B and double-knockout hTERT-RPE1 cells. Ciliogenesis assays showed the redundancy of both proteins while the polyglutamylation of cilia was affected in single knockouts. The localization of other IFT components was not affected by the depletion of a single paralogue. A loss of both proteins led to a severe ciliogenesis defect, resulting in no cilia formation, which was rescued by TTC30A or B. The redundancy can be explained by the highly similar interaction patterns of the paralogues; both equally interact with the IFT-B machinery. Our study demonstrates that a loss of one TTC30 paralogue can mostly be compensated by the other, thus preventing severe ciliary defects. However, cells assemble shorter cilia, which are potentially limited in their function, especially because of impaired polyglutamylation. A complete loss of both proteins leads to a deficit in IFT complex B integrity followed by disrupted IFT and subsequently no cilia formation.
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Affiliation(s)
- Felix Hoffmann
- Institute for Ophthalmic Research, Eberhard Karls University Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; (F.H.); (S.B.); (K.J.); (F.K.); (T.S.); (F.W.); (K.B.); (M.U.)
| | - Sylvia Bolz
- Institute for Ophthalmic Research, Eberhard Karls University Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; (F.H.); (S.B.); (K.J.); (F.K.); (T.S.); (F.W.); (K.B.); (M.U.)
| | - Katrin Junger
- Institute for Ophthalmic Research, Eberhard Karls University Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; (F.H.); (S.B.); (K.J.); (F.K.); (T.S.); (F.W.); (K.B.); (M.U.)
| | - Franziska Klose
- Institute for Ophthalmic Research, Eberhard Karls University Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; (F.H.); (S.B.); (K.J.); (F.K.); (T.S.); (F.W.); (K.B.); (M.U.)
| | - Timm Schubert
- Institute for Ophthalmic Research, Eberhard Karls University Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; (F.H.); (S.B.); (K.J.); (F.K.); (T.S.); (F.W.); (K.B.); (M.U.)
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany
| | - Franziska Woerz
- Institute for Ophthalmic Research, Eberhard Karls University Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; (F.H.); (S.B.); (K.J.); (F.K.); (T.S.); (F.W.); (K.B.); (M.U.)
| | - Karsten Boldt
- Institute for Ophthalmic Research, Eberhard Karls University Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; (F.H.); (S.B.); (K.J.); (F.K.); (T.S.); (F.W.); (K.B.); (M.U.)
| | - Marius Ueffing
- Institute for Ophthalmic Research, Eberhard Karls University Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; (F.H.); (S.B.); (K.J.); (F.K.); (T.S.); (F.W.); (K.B.); (M.U.)
| | - Tina Beyer
- Institute for Ophthalmic Research, Eberhard Karls University Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; (F.H.); (S.B.); (K.J.); (F.K.); (T.S.); (F.W.); (K.B.); (M.U.)
- Correspondence:
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Behrens C, Yadav SC, Korympidou MM, Zhang Y, Haverkamp S, Irsen S, Schaedler A, Lu X, Liu Z, Lause J, St-Pierre F, Franke K, Vlasits A, Dedek K, Smith RG, Euler T, Berens P, Schubert T. Retinal horizontal cells use different synaptic sites for global feedforward and local feedback signaling. Curr Biol 2022; 32:545-558.e5. [PMID: 34910950 PMCID: PMC8886496 DOI: 10.1016/j.cub.2021.11.055] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 10/19/2021] [Accepted: 11/23/2021] [Indexed: 11/19/2022]
Abstract
In the outer plexiform layer (OPL) of the mammalian retina, cone photoreceptors (cones) provide input to more than a dozen types of cone bipolar cells (CBCs). In the mouse, this transmission is modulated by a single horizontal cell (HC) type. HCs perform global signaling within their laterally coupled network but also provide local, cone-specific feedback. However, it is unknown how HCs provide local feedback to cones at the same time as global forward signaling to CBCs and where the underlying synapses are located. To assess how HCs simultaneously perform different modes of signaling, we reconstructed the dendritic trees of five HCs as well as cone axon terminals and CBC dendrites in a serial block-face electron microscopy volume and analyzed their connectivity. In addition to the fine HC dendritic tips invaginating cone axon terminals, we also identified "bulbs," short segments of increased dendritic diameter on the primary dendrites of HCs. These bulbs are in an OPL stratum well below the cone axon terminal base and make contacts with other HCs and CBCs. Our results from immunolabeling, electron microscopy, and glutamate imaging suggest that HC bulbs represent GABAergic synapses that do not receive any direct photoreceptor input. Together, our data suggest the existence of two synaptic strata in the mouse OPL, spatially separating cone-specific feedback and feedforward signaling to CBCs. A biophysical model of a HC dendritic branch and voltage imaging support the hypothesis that this spatial arrangement of synaptic contacts allows for simultaneous local feedback and global feedforward signaling by HCs.
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Affiliation(s)
- Christian Behrens
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience, University of Tübingen, Otfried-Müller-Str. 27, 72076 Tübingen, Germany
| | - Shubhash Chandra Yadav
- Neurosensorics/Animal Navigation, Institute for Biology and Environmental Sciences, University of Oldenburg, Carl-von-Ossietzky-Str. 9-11, 26111 Oldenburg, Germany
| | - Maria M Korympidou
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience, University of Tübingen, Otfried-Müller-Str. 27, 72076 Tübingen, Germany
| | - Yue Zhang
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience, University of Tübingen, Otfried-Müller-Str. 27, 72076 Tübingen, Germany
| | - Silke Haverkamp
- Department of Computational Neuroethology, Center of Advanced European Studies and Research (caesar), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Stephan Irsen
- Electron Microscopy and Analytics, Center of Advanced European Studies and Research (caesar), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Anna Schaedler
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience, University of Tübingen, Otfried-Müller-Str. 27, 72076 Tübingen, Germany
| | - Xiaoyu Lu
- Systems, Synthetic, and Physical Biology Program, Rice University, 6500 Main St., Houston, TX 77005, USA
| | - Zhuohe Liu
- Department of Electrical and Computer Engineering, Rice University, 6100 Main St., Houston, TX 77005, USA
| | - Jan Lause
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience, University of Tübingen, Otfried-Müller-Str. 27, 72076 Tübingen, Germany
| | - François St-Pierre
- Systems, Synthetic, and Physical Biology Program, Rice University, 6500 Main St., Houston, TX 77005, USA; Department of Electrical and Computer Engineering, Rice University, 6100 Main St., Houston, TX 77005, USA; Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Katrin Franke
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany
| | - Anna Vlasits
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany
| | - Karin Dedek
- Neurosensorics/Animal Navigation, Institute for Biology and Environmental Sciences, University of Oldenburg, Carl-von-Ossietzky-Str. 9-11, 26111 Oldenburg, Germany
| | - Robert G Smith
- Department of Neuroscience, University of Pennsylvania, 422 Curie Blvd, Philadelphia, PA 19104, USA
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany
| | - Philipp Berens
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Tübingen AI Center, University of Tübingen, Maria-von-Linden-Straße 6, 72076 Tübingen, Germany
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Str. 7, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany.
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9
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Arsić A, Hagemann C, Stajković N, Schubert T, Nikić-Spiegel I. Minimal genetically encoded tags for fluorescent protein labeling in living neurons. Nat Commun 2022; 13:314. [PMID: 35031604 PMCID: PMC8760255 DOI: 10.1038/s41467-022-27956-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 12/22/2021] [Indexed: 12/25/2022] Open
Abstract
Modern light microscopy, including super-resolution techniques, has brought about a demand for small labeling tags that bring the fluorophore closer to the target. This challenge can be addressed by labeling unnatural amino acids (UAAs) with bioorthogonal click chemistry. The minimal size of the UAA and the possibility to couple the fluorophores directly to the protein of interest with single-residue precision in living cells make click labeling unique. Here, we establish click labeling in living primary neurons and use it for fixed-cell, live-cell, dual-color pulse-chase, and super-resolution microscopy of neurofilament light chain (NFL). We also show that click labeling can be combined with CRISPR/Cas9 genome engineering for tagging endogenous NFL. Due to its versatile nature and compatibility with advanced multicolor microscopy techniques, we anticipate that click labeling will contribute to novel discoveries in the neurobiology field.
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Affiliation(s)
- Aleksandra Arsić
- Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076, Tübingen, Germany
- Graduate Training Centre of Neuroscience, International Max Planck Research School, University of Tübingen, Otfried-Müller-Straße 27, 72076, Tübingen, Germany
| | - Cathleen Hagemann
- Graduate Training Centre of Neuroscience, International Max Planck Research School, University of Tübingen, Otfried-Müller-Straße 27, 72076, Tübingen, Germany
| | - Nevena Stajković
- Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076, Tübingen, Germany
- Graduate Training Centre of Neuroscience, International Max Planck Research School, University of Tübingen, Otfried-Müller-Straße 27, 72076, Tübingen, Germany
| | - Timm Schubert
- Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076, Tübingen, Germany
- Institute for Ophthalmic Research, University of Tübingen, Elfriede-Aulhorn-Straße 7, 72076, Tübingen, Germany
| | - Ivana Nikić-Spiegel
- Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076, Tübingen, Germany.
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10
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Appelt K, Takes M, Zech CJ, Blackham KA, Schubert T. Complication rates of percutaneous brachial artery puncture: effect of live ultrasound guidance. CVIR Endovasc 2021; 4:74. [PMID: 34633563 PMCID: PMC8505595 DOI: 10.1186/s42155-021-00262-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 09/27/2021] [Indexed: 11/24/2022] Open
Abstract
Purpose The current literature on the use of brachial artery access is controversial. Some studies found increased puncture site complications. Others found no higher complication rates than in patients with femoral or radial access. The purpose of this study was to determine the impact of ultrasound (US)-guidance on access site complications. Materials and methods This is a single-center retrospective study of all consecutive patients with brachial arterial access for interventional procedures. Complications were classified into minor complications (conservative treatment only) and major complications (requiring surgical intervention). The brachial artery was cannulated in the antecubital fossa under US-guidance. After the intervention, manual compression or closure devices, both followed by a compression bandage for 3 h, either achieved hemostasis. Results Seventy-five procedures in seventy-one patients were performed in the study period using brachial access. Access was successful in all cases (100%). Procedures in different vascular territories were performed: neurovascular (10/13.5%), upper extremity (32/43.2%), visceral (20/27.0%), and lower extremity (12/16.3%). Sheath size ranged from 3.2F to 8F (mean: 5F). Closure devices were used in 17 cases (22.7%). In total, six complications were observed (8.0%), four minor complications (5.3%, mostly puncture site hematomas), and two major complications, that needed surgical treatment (2.7%). No brachial artery thrombosis or upper extremity ischemia occurred. Conclusion Exclusive use of US-guidance resulted in a low risk of brachial artery access site complications in our study compared to the literature. US-guidance has been proven to reduce the risk of access site complications in several studies in femoral access. In addition, brachial artery access yields a high technical success rate and requires no additional injection of spasmolytic medication. Sheath size was the single significant predictor for complications.
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Affiliation(s)
- K Appelt
- Radiology and Nuclear Medicine Clinic, University Hospital Basel, Basel, Switzerland.
| | - M Takes
- Radiology and Nuclear Medicine Clinic, University Hospital Basel, Basel, Switzerland
| | - C J Zech
- Radiology and Nuclear Medicine Clinic, University Hospital Basel, Basel, Switzerland
| | - K A Blackham
- Radiology and Nuclear Medicine Clinic, University Hospital Basel, Basel, Switzerland
| | - T Schubert
- Radiology and Nuclear Medicine Clinic, University Hospital Basel, Basel, Switzerland.,Department of Neuroradiology, University Hospital Zurich, Zürich, Switzerland
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11
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Lechleitner A, Schubert T, Lehner M, Hofer W. Modellierung einer industriellen Kunststoff Co‐Pyrolyse. CHEM-ING-TECH 2020. [DOI: 10.1002/cite.202055167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- A. Lechleitner
- Montanuniversität Lehrstuhl für Verfahrenstechnik des industriellen Umweltschutzes Franz-Josef-Str. 18 8700 Leoben Österreich
| | - T. Schubert
- Montanuniversität Lehrstuhl für Verfahrenstechnik des industriellen Umweltschutzes Franz-Josef-Str. 18 8700 Leoben Österreich
| | - M. Lehner
- Montanuniversität Lehrstuhl für Verfahrenstechnik des industriellen Umweltschutzes Franz-Josef-Str. 18 8700 Leoben Österreich
| | - W. Hofer
- OMV Refining & Marketing GmbH RD-I Technology&Innovation Mgmt P2O Mannswörther Str. 28 2320 Schwechat Österreich
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12
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Szatko KP, Korympidou MM, Ran Y, Berens P, Dalkara D, Schubert T, Euler T, Franke K. Neural circuits in the mouse retina support color vision in the upper visual field. Nat Commun 2020; 11:3481. [PMID: 32661226 PMCID: PMC7359335 DOI: 10.1038/s41467-020-17113-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 04/21/2020] [Indexed: 02/06/2023] Open
Abstract
Color vision is essential for an animal’s survival. It starts in the retina, where signals from different photoreceptor types are locally compared by neural circuits. Mice, like most mammals, are dichromatic with two cone types. They can discriminate colors only in their upper visual field. In the corresponding ventral retina, however, most cones display the same spectral preference, thereby presumably impairing spectral comparisons. In this study, we systematically investigated the retinal circuits underlying mouse color vision by recording light responses from cones, bipolar and ganglion cells. Surprisingly, most color-opponent cells are located in the ventral retina, with rod photoreceptors likely being involved. Here, the complexity of chromatic processing increases from cones towards the retinal output, where non-linear center-surround interactions create specific color-opponent output channels to the brain. This suggests that neural circuits in the mouse retina are tuned to extract color from the upper visual field, aiding robust detection of predators and ensuring the animal’s survival. Mice are able to discriminate colors, at least in the upper visual field. Here, the authors provide a comprehensive characterization of retinal circuits underlying this behavior.
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Affiliation(s)
- Klaudia P Szatko
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Graduate Training Center of Neuroscience, International Max Planck Research School, University of Tübingen, Tübingen, Germany
| | - Maria M Korympidou
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Graduate Training Center of Neuroscience, International Max Planck Research School, University of Tübingen, Tübingen, Germany.,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Yanli Ran
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Philipp Berens
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Institute for Bioinformatics and Medical Informatics, University of Tübingen, Tübingen, Germany
| | - Deniz Dalkara
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Katrin Franke
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany. .,Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany. .,Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.
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13
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Demerath T, Blackham K, Anastasopoulos C, Block K, Stieltjes B, Schubert T. Golden-Angle Radial Sparse Parallel (GRASP) MRI differentiates head & neck paragangliomas from schwannomas. Magn Reson Imaging 2020; 70:73-80. [DOI: 10.1016/j.mri.2020.04.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 03/30/2020] [Accepted: 04/10/2020] [Indexed: 11/24/2022]
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14
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Ran Y, Huang Z, Baden T, Schubert T, Baayen H, Berens P, Franke K, Euler T. Type-specific dendritic integration in mouse retinal ganglion cells. Nat Commun 2020; 11:2101. [PMID: 32355170 PMCID: PMC7193577 DOI: 10.1038/s41467-020-15867-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 03/30/2020] [Indexed: 11/17/2022] Open
Abstract
Neural computation relies on the integration of synaptic inputs across a neuron’s dendritic arbour. However, it is far from understood how different cell types tune this process to establish cell-type specific computations. Here, using two-photon imaging of dendritic Ca2+ signals, electrical recordings of somatic voltage and biophysical modelling, we demonstrate that four morphologically distinct types of mouse retinal ganglion cells with overlapping excitatory synaptic input (transient Off alpha, transient Off mini, sustained Off, and F-mini Off) exhibit type-specific dendritic integration profiles: in contrast to the other types, dendrites of transient Off alpha cells were spatially independent, with little receptive field overlap. The temporal correlation of dendritic signals varied also extensively, with the highest and lowest correlation in transient Off mini and transient Off alpha cells, respectively. We show that differences between cell types can likely be explained by differences in backpropagation efficiency, arising from the specific combinations of dendritic morphology and ion channel densities. Neurons compute by integrating synaptic inputs across their dendritic arbor. Here, the authors show that distinct cell-types of mouse retinal ganglion cells that receive similar excitatory inputs have different biophysical mechanisms of input integration to generate their unique response tuning.
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Affiliation(s)
- Yanli Ran
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Ziwei Huang
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Tom Baden
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, UK
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Harald Baayen
- Department of Linguistics, University of Tübingen, Tübingen, Germany
| | - Philipp Berens
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.,Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Institute of Bioinformatics and Medical Informatics, University of Tübingen, Tübingen, Germany
| | - Katrin Franke
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.,Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany. .,Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany. .,Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany.
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15
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Zhao Z, Klindt DA, Maia Chagas A, Szatko KP, Rogerson L, Protti DA, Behrens C, Dalkara D, Schubert T, Bethge M, Franke K, Berens P, Ecker AS, Euler T. The temporal structure of the inner retina at a single glance. Sci Rep 2020; 10:4399. [PMID: 32157103 PMCID: PMC7064538 DOI: 10.1038/s41598-020-60214-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 02/09/2020] [Indexed: 12/12/2022] Open
Abstract
The retina decomposes visual stimuli into parallel channels that encode different features of the visual environment. Central to this computation is the synaptic processing in a dense layer of neuropil, the so-called inner plexiform layer (IPL). Here, different types of bipolar cells stratifying at distinct depths relay the excitatory feedforward drive from photoreceptors to amacrine and ganglion cells. Current experimental techniques for studying processing in the IPL do not allow imaging the entire IPL simultaneously in the intact tissue. Here, we extend a two-photon microscope with an electrically tunable lens allowing us to obtain optical vertical slices of the IPL, which provide a complete picture of the response diversity of bipolar cells at a "single glance". The nature of these axial recordings additionally allowed us to isolate and investigate batch effects, i.e. inter-experimental variations resulting in systematic differences in response speed. As a proof of principle, we developed a simple model that disentangles biological from experimental causes of variability and allowed us to recover the characteristic gradient of response speeds across the IPL with higher precision than before. Our new framework will make it possible to study the computations performed in the central synaptic layer of the retina more efficiently.
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Affiliation(s)
- Zhijian Zhao
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
| | - David A Klindt
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
- Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
- Graduate Training Centre of Neuroscience, University of Tübingen, Tübingen, Germany
- Institute for Theoretical Physics, University of Tübingen, Tübingen, Germany
| | - André Maia Chagas
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
- Graduate Training Centre of Neuroscience, University of Tübingen, Tübingen, Germany
| | - Klaudia P Szatko
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
- Graduate Training Centre of Neuroscience, University of Tübingen, Tübingen, Germany
| | - Luke Rogerson
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
- Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
- Graduate Training Centre of Neuroscience, University of Tübingen, Tübingen, Germany
| | - Dario A Protti
- Department of Physiology and Bosch Institute, The University of Sydney, Sydney, Australia
| | - Christian Behrens
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
- Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
| | - Deniz Dalkara
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
| | - Matthias Bethge
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
- Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
- Institute for Theoretical Physics, University of Tübingen, Tübingen, Germany
- Center for Neuroscience and Artificial Intelligence, Baylor College of Medicine, Houston, TX, USA
| | - Katrin Franke
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
- Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
| | - Philipp Berens
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
- Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
- Institute of Bioinformatics and Medical Informatics, University of Tübingen, Tübingen, Germany
| | - Alexander S Ecker
- Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
- Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
- Institute for Theoretical Physics, University of Tübingen, Tübingen, Germany
- Center for Neuroscience and Artificial Intelligence, Baylor College of Medicine, Houston, TX, USA
- Department of Computer Science, University of Göttingen, Göttingen, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.
- Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany.
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16
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Power MJ, Rogerson LE, Schubert T, Berens P, Euler T, Paquet-Durand F. Systematic spatiotemporal mapping reveals divergent cell death pathways in three mouse models of hereditary retinal degeneration. J Comp Neurol 2019; 528:1113-1139. [PMID: 31710697 DOI: 10.1002/cne.24807] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 08/06/2019] [Accepted: 10/20/2019] [Indexed: 12/20/2022]
Abstract
Calcium (Ca2+ ) dysregulation has been linked to neuronal cell death, including in hereditary retinal degeneration. Ca2+ dysregulation is thought to cause rod and cone photoreceptor cell death. Spatial and temporal heterogeneities in retinal disease models have hampered validation of this hypothesis. We examined the role of Ca2+ in photoreceptor degeneration, assessing the activation pattern of Ca2+ -dependent calpain proteases, generating spatiotemporal maps of the entire retina in the cpfl1 mouse model for primary cone degeneration, and in the rd1 and rd10 models for primary rod degeneration. We used Gaussian process models to distinguish the temporal sequences of degenerative molecular processes from other variability sources.In the rd1 and rd10 models, spatiotemporal pattern of increased calpain activity matched the progression of primary rod degeneration. High calpain activity coincided with activation of the calpain-2 isoform but not with calpain-1, suggesting differential roles for both calpain isoforms. Primary rod loss was linked to upregulation of apoptosis-inducing factor, although only a minute fraction of cells showed activity of the apoptotic marker caspase-3. After primary rod degeneration concluded, caspase-3 activation appeared in cones, suggesting apoptosis as the dominant mechanism for secondary cone loss. Gaussian process models highlighted calpain activity as a key event during primary rod photoreceptor cell death. Our data suggest a causal link between Ca2+ dysregulation and primary, nonapoptotic degeneration of photoreceptors and a role for apoptosis in secondary degeneration of cones, highlighting the importance of the spatial and temporal location of key molecular events, which may guide the evaluation of new therapies.
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Affiliation(s)
- Michael J Power
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany.,Graduate Training Centre of Neuroscience (GTC), University of Tübingen, Tübingen, Germany
| | - Luke E Rogerson
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany.,Graduate Training Centre of Neuroscience (GTC), University of Tübingen, Tübingen, Germany.,Bernstein Center for Computational Neuroscience, Tübingen, Germany.,Institute for Bioinformatics and Medical Informatics, University of Tübingen, Tübingen, Germany
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
| | - Philipp Berens
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany.,Bernstein Center for Computational Neuroscience, Tübingen, Germany.,Institute for Bioinformatics and Medical Informatics, University of Tübingen, Tübingen, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany.,Bernstein Center for Computational Neuroscience, Tübingen, Germany
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17
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Sokolakis I, Schubert T, Oelschläger M, Krebs M, Gschwend J, Holzapfel K, Kübler H, Gakis G, Hatzichristodoulou G. HP-06-001 The role of magnetic resonance imaging for the diagnosis of penile fracture in real life emergency settings: Comparative analysis with intraoperative findings. J Sex Med 2019. [DOI: 10.1016/j.jsxm.2019.03.141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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18
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19
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Wu Y, Shaughnessy G, Hoffman CA, Oberstar EL, Schafer S, Schubert T, Ruedinger KL, Davis BJ, Mistretta CA, Strother CM, Speidel MA. Quantification of Blood Velocity with 4D Digital Subtraction Angiography Using the Shifted Least-Squares Method. AJNR Am J Neuroradiol 2018; 39:1871-1877. [PMID: 30213811 PMCID: PMC6177311 DOI: 10.3174/ajnr.a5793] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 06/11/2018] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE 4D-DSA provides time-resolved 3D-DSA volumes with high temporal and spatial resolutions. The purpose of this study is to investigate a shifted least squares method to estimate the blood velocity from the 4D DSA images. Quantitative validation was performed using a flow phantom with an ultrasonic flow probe as ground truth. Quantification of blood velocity in human internal carotid arteries was compared with measurements generated from 3D phase-contrast MR imaging. MATERIALS AND METHODS The centerlines of selected vascular segments and the time concentration curves of each voxel along the centerlines were determined from the 4D-DSA dataset. The temporal shift required to achieve a minimum difference between any point and other points along the centerline of a segment was calculated. The temporal shift as a function of centerline point position was fit to a straight line to generate the velocity. The proposed shifted least-squares method was first validated using a flow phantom study. Blood velocities were also estimated in the 14 ICAs of human subjects who had both 4D-DSA and phase-contrast MR imaging studies. Linear regression and correlation analysis were performed on both the phantom study and clinical study, respectively. RESULTS Mean velocities of the flow phantom calculated from 4D-DSA matched very well with ultrasonic flow probe measurements with 11% relative root mean square error. Mean blood velocities of ICAs calculated from 4D-DSA correlated well with phase-contrast MR imaging measurements with Pearson correlation coefficient r = 0.835. CONCLUSIONS The availability of 4D-DSA provides the opportunity to use the shifted least-squares method to estimate velocity in vessels within a 3D volume.
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Affiliation(s)
- Y Wu
- From the Departments of Medical Physics (Y.W., G.S., C.A.H., C.A.M., M.A.S.)
| | - G Shaughnessy
- From the Departments of Medical Physics (Y.W., G.S., C.A.H., C.A.M., M.A.S.)
| | - C A Hoffman
- From the Departments of Medical Physics (Y.W., G.S., C.A.H., C.A.M., M.A.S.)
| | | | | | - T Schubert
- Radiology (C.A.M., C.M.S., T.S.).,Department of Radiology and Nuclear Medicine (T.S.), Basel University Hospital, Basel, Switzerland
| | | | - B J Davis
- Biomedical Engineering (E.L.O., K.L.R., B.J.D.)
| | - C A Mistretta
- From the Departments of Medical Physics (Y.W., G.S., C.A.H., C.A.M., M.A.S.).,Radiology (C.A.M., C.M.S., T.S.)
| | | | - M A Speidel
- From the Departments of Medical Physics (Y.W., G.S., C.A.H., C.A.M., M.A.S.).,Medicine (M.A.S.), University of Wisconsin, Madison, Wisconsin
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20
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Veruki ML, Schubert T. Neural Circuits: When Neurons 'Remember' Their Connectivity. Curr Biol 2018; 28:R662-R664. [PMID: 29870705 DOI: 10.1016/j.cub.2018.04.059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Loss of neurons due to injury or neurodegeneration can lead to dramatically altered neural circuits, resulting in reduced or lost function. One mechanism to preserve function could be to re-establish the stereotypic connectivity among the remnant neurons. In the mammalian retina, such a selective re-wiring has now been described.
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Affiliation(s)
- Margaret L Veruki
- Department of Biomedicine, University of Bergen, 5009 Bergen, Norway
| | - Timm Schubert
- Centre for Integrative Neuroscience (CIN) and Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany.
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21
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Perlepe V, Omoumi P, Larbi A, Putineanu D, Dubuc JE, Schubert T, Vande Berg B. Can we assess healing of surgically treated long bone fractures on radiograph? Diagn Interv Imaging 2018; 99:381-386. [DOI: 10.1016/j.diii.2018.02.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 02/12/2018] [Accepted: 02/16/2018] [Indexed: 11/27/2022]
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22
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Lee MJ, Srivastava P, Rogerson L, Berens P, Euler T, Schubert T, Zeck G. Combining two photon microscopy and CMOS MEA to uncover the mechanism of aberrant activity in blind retina. Front Cell Neurosci 2018. [DOI: 10.3389/conf.fncel.2018.38.00022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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23
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Chapot CA, Behrens C, Rogerson LE, Baden T, Pop S, Berens P, Euler T, Schubert T. Local Signals in Mouse Horizontal Cell Dendrites. Curr Biol 2017; 27:3603-3615.e5. [PMID: 29174891 DOI: 10.1016/j.cub.2017.10.050] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 09/01/2017] [Accepted: 10/19/2017] [Indexed: 01/07/2023]
Abstract
The mouse retina contains a single type of horizontal cell, a GABAergic interneuron that samples from all cone photoreceptors within reach and modulates their glutamatergic output via parallel feedback mechanisms. Because horizontal cells form an electrically coupled network, they have been implicated in global signal processing, such as large-scale contrast enhancement. Recently, it has been proposed that horizontal cells can also act locally at the level of individual cone photoreceptors. To test this possibility physiologically, we used two-photon microscopy to record light stimulus-evoked Ca2+ signals in cone axon terminals and horizontal cell dendrites as well as glutamate release in the outer plexiform layer. By selectively stimulating the two mouse cone opsins with green and UV light, we assessed whether signals from individual cones remain isolated within horizontal cell dendritic tips or whether they spread across the dendritic arbor. Consistent with the mouse's opsin expression gradient, we found that the Ca2+ signals recorded from dendrites of dorsal horizontal cells were dominated by M-opsin and those of ventral horizontal cells by S-opsin activation. The signals measured in neighboring horizontal cell dendritic tips varied markedly in their chromatic preference, arguing against global processing. Rather, our experimental data and results from biophysically realistic modeling support the idea that horizontal cells can process cone input locally, extending the classical view of horizontal cell function. Pharmacologically removing horizontal cells from the circuitry reduced the sensitivity of the cone signal to low frequencies, suggesting that local horizontal cell feedback shapes the temporal properties of cone output.
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Affiliation(s)
- Camille A Chapot
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience, University of Tübingen, 72076 Tübingen, Germany
| | - Christian Behrens
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, University of Tübingen, 72076 Tübingen, Germany
| | - Luke E Rogerson
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, University of Tübingen, 72076 Tübingen, Germany
| | - Tom Baden
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; School of Life Sciences, University of Sussex, Brighton BN1 9RH, UK
| | - Sinziana Pop
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience, University of Tübingen, 72076 Tübingen, Germany
| | - Philipp Berens
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, University of Tübingen, 72076 Tübingen, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, University of Tübingen, 72076 Tübingen, Germany.
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, 72076 Tübingen, Germany; Center for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany.
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24
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Rogerson LE, Behrens C, Euler T, Berens P, Schubert T. Connectomics of synaptic microcircuits: lessons from the outer retina. J Physiol 2017; 595:5517-5524. [PMID: 28295344 PMCID: PMC5556146 DOI: 10.1113/jp273671] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 02/10/2017] [Indexed: 01/16/2023] Open
Abstract
Photoreceptors form a sophisticated synaptic complex with bipolar and horizontal cells, transmitting the signals generated by the phototransduction cascade to downstream retinal circuitry. The cone photoreceptor synapse shows several characteristic anatomical connectivity motifs that shape signal transfer: typically, ON-cone bipolar cells receive photoreceptor input through invaginating synapses; OFF-cone bipolar cells form basal synapses with photoreceptors. Both ON- and OFF-cone bipolar cells are believed to sample from all cone photoreceptors within their dendritic span. Electron microscopy and immunolabelling studies have established the robustness of these motifs, but have been limited by trade-offs in sample size and spatial resolution, respectively, constraining precise quantitative investigation to a few individual cells. 3D-serial electron microscopy overcomes these limitations and has permitted complete sets of neurons to be reconstructed over a comparatively large section of retinal tissue. Although the published mouse dataset lacks labels for synaptic structures, the characteristic anatomical motifs at the photoreceptor synapse can be exploited to identify putative synaptic contacts, which has enabled the development of a quantitative description of outer retinal connectivity. This revealed unexpected exceptions to classical motifs, including substantial interaction between rod and cone pathways at the photoreceptor synapse, sparse photoreceptor sampling and atypical contacts. Here, we summarize what was learned from this study in a more general context: we consider both the implications and limitations of the study and identify promising avenues for future research.
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Affiliation(s)
- Luke Edward Rogerson
- Institute for Ophthalmic ResearchUniversity of Tübingen72076TübingenGermany
- Centre for Integrative NeuroscienceUniversity of Tübingen72076TübingenGermany
- Bernstein Center for Computational NeuroscienceUniversity of Tübingen72076TübingenGermany
- Graduate Training Centre of NeuroscienceUniversity of Tübingen72076TübingenGermany
| | - Christian Behrens
- Institute for Ophthalmic ResearchUniversity of Tübingen72076TübingenGermany
- Centre for Integrative NeuroscienceUniversity of Tübingen72076TübingenGermany
- Bernstein Center for Computational NeuroscienceUniversity of Tübingen72076TübingenGermany
- Graduate Training Centre of NeuroscienceUniversity of Tübingen72076TübingenGermany
| | - Thomas Euler
- Institute for Ophthalmic ResearchUniversity of Tübingen72076TübingenGermany
- Centre for Integrative NeuroscienceUniversity of Tübingen72076TübingenGermany
- Bernstein Center for Computational NeuroscienceUniversity of Tübingen72076TübingenGermany
| | - Philipp Berens
- Institute for Ophthalmic ResearchUniversity of Tübingen72076TübingenGermany
- Centre for Integrative NeuroscienceUniversity of Tübingen72076TübingenGermany
- Bernstein Center for Computational NeuroscienceUniversity of Tübingen72076TübingenGermany
| | - Timm Schubert
- Institute for Ophthalmic ResearchUniversity of Tübingen72076TübingenGermany
- Centre for Integrative NeuroscienceUniversity of Tübingen72076TübingenGermany
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25
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van Steenberghe M, Schubert T, Guiot Y, Goebbels RM, Gianello P. Improvement of mesh recolonization in abdominal wall reconstruction with adipose vs. bone marrow mesenchymal stem cells in a rodent model. J Pediatr Surg 2017; 52:1355-1362. [PMID: 27939203 DOI: 10.1016/j.jpedsurg.2016.11.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/03/2016] [Accepted: 11/27/2016] [Indexed: 01/31/2023]
Abstract
BACKGROUND Reconstruction of muscle defects remains a challenge. Our work assessed the potential of an engineered construct made of a human acellular collagen matrix (HACM) seeded with porcine mesenchymal stem cells (MSCs) to reconstruct abdominal wall muscle defects in a rodent model. METHODS This study compared 2 sources of MSCs (bone-marrow, BMSCs, and adipose, ASCs) in vitro and in vivo for parietal defect reconstruction. Cellular viability and growth factor release (VEGF, FGF-Beta, HGF, IGF-1, TGF-Beta) were investigated under normoxic/hypoxic culture conditions. Processed and recellularized HACMs were mechanically assessed. The construct was tested in vivo in full thickness abdominal wall defect treated with HACM alone vs. HACM+ASCs or BMSCs (n=14). Tissue remodeling was studied at day 30 for neo-angiogenesis and muscular reconstruction. RESULTS A significantly lower secretion of IGF was observed with ASCs vs. BMSCs under hypoxic conditions (-97.6%, p<0.005) whereas significantly higher VEGF/FGF secretions were found with ASCs (+92%, p<0.001 and +72%, p<0.05, respectively). Processing and recellularization did not impair the mechanical properties of the HACM. In vivo, angiogenesis and muscle healing were significantly improved by the HACM+ASCs in comparison to BMSCs (p<0.05) at day 30. CONCLUSION A composite graft made of an HACM seeded with ASCs can improve muscle repair by specific growth factor release in hypoxic conditions and by in vivo remodeling (neo-angiogenesis/graft integration) while maintaining mechanical properties.
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Affiliation(s)
- M van Steenberghe
- Université catholique de Louvain, Secteur des Sciences de la Santé, Institut de Recherche Expérimentale et Clinique, Pôle de Chirurgie Expérimentale et Transplantation (CHEX), Avenue Mounier 55, B-1200 Brussels, Belgium; Cardiac Surgery Department, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
| | - T Schubert
- Université catholique de Louvain, Secteur des Sciences de la Santé, Institut de Recherche Expérimentale et Clinique, Pôle de Chirurgie Expérimentale et Transplantation (CHEX), Avenue Mounier 55, B-1200 Brussels, Belgium; Cliniques universitaires Saint-Luc, Service d'orthopédie et de traumatologie de l'appareil locomoteur, Avenue Hippocrate 10, B-1200 Brussels, Belgium
| | - Y Guiot
- Cliniques universitaires Saint-Luc, Service d'anatomopathologie, Avenue Hippocrate 10, B-1200 Brussels, Belgium
| | - R M Goebbels
- Université catholique de Louvain, Secteur des Sciences de la Santé, Institut de Recherche Expérimentale et Clinique, Pôle de Chirurgie Expérimentale et Transplantation (CHEX), Avenue Mounier 55, B-1200 Brussels, Belgium
| | - P Gianello
- Université catholique de Louvain, Secteur des Sciences de la Santé, Institut de Recherche Expérimentale et Clinique, Pôle de Chirurgie Expérimentale et Transplantation (CHEX), Avenue Mounier 55, B-1200 Brussels, Belgium
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26
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Chapot CA, Euler T, Schubert T. How do horizontal cells 'talk' to cone photoreceptors? Different levels of complexity at the cone-horizontal cell synapse. J Physiol 2017; 595:5495-5506. [PMID: 28378516 DOI: 10.1113/jp274177] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 03/27/2017] [Indexed: 11/08/2022] Open
Abstract
The first synapse of the retina plays a fundamental role in the visual system. Due to its importance, it is critical that it encodes information from the outside world with the greatest accuracy and precision possible. Cone photoreceptor axon terminals contain many individual synaptic sites, each represented by a presynaptic structure called a 'ribbon'. These synapses are both highly sophisticated and conserved. Each ribbon relays the light signal to one ON cone bipolar cell and several OFF cone bipolar cells, while two dendritic processes from a GABAergic interneuron, the horizontal cell, modulate the cone output via parallel feedback mechanisms. The presence of these three partners within a single synapse has raised numerous questions, and its anatomical and functional complexity is still only partially understood. However, the understanding of this synapse has recently evolved, as a consequence of progress in understanding dendritic signal processing and its role in facilitating global versus local signalling. Indeed, for the downstream retinal network, dendritic processing in horizontal cells may be essential, as they must support important functional operations such as contrast enhancement, which requires spatial averaging of the photoreceptor array, while at the same time preserving accurate spatial information. Here, we review recent progress made towards a better understanding of the cone synapse, with an emphasis on horizontal cell function, and discuss why such complexity might be necessary for early visual processing.
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Affiliation(s)
- Camille A Chapot
- Institute for Ophthalmic Research, University of Tübingen, 72076, Tübingen, Germany.,Centre for Integrative Neuroscience, University of Tübingen, 72076, Tübingen, Germany.,Graduate Training Centre of Neuroscience, University of Tübingen, 72076, Tübingen, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, 72076, Tübingen, Germany.,Centre for Integrative Neuroscience, University of Tübingen, 72076, Tübingen, Germany.,Bernstein Centre for Computational Neuroscience, University of Tübingen, 72076, Tübingen, Germany
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, 72076, Tübingen, Germany.,Centre for Integrative Neuroscience, University of Tübingen, 72076, Tübingen, Germany
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27
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Sandoval-Garcia C, Yang P, Schubert T, Schafer S, Hetzel S, Ahmed A, Strother C. Comparison of the Diagnostic Utility of 4D-DSA with Conventional 2D- and 3D-DSA in the Diagnosis of Cerebrovascular Abnormalities. AJNR Am J Neuroradiol 2017; 38:729-734. [PMID: 28279986 DOI: 10.3174/ajnr.a5137] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 11/15/2016] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE 4D-DSA is a time-resolved technique that allows viewing of a contrast bolus at any time and from any desired viewing angle. Our hypothesis was that the information content in a 4D-DSA reconstruction was essentially equivalent to that in a combination of 2D acquisitions and a 3D-DSA reconstruction. MATERIALS AND METHODS Twenty-six consecutive patients who had both 2D- and 3D-DSA acquisitions were included in the study. The angiography report was used to obtain diagnoses and characteristics of abnormalities. Diagnoses included AVM/AVFs, aneurysms, stenosis, and healthy individuals. 4D-DSA reconstructions were independently reviewed by 3 experienced observers who had no part in the clinical care. Using an electronic evaluation form, these observers recorded their assessments based only on the 4D reconstructions. The clinical evaluations were then compared with the 4D evaluations for diagnosis and lesion characteristics. RESULTS Results showed both interrater and interclass agreements (κ = 0.813 and 0.858). Comparing the 4D diagnosis with the clinical diagnosis for the 3 observers yielded κ values of 0.906, 0.912, and 0.906. The κ values for agreement among the 3 observers for the type of abnormality were 0.949, 0.845, and 0.895. There was complete agreement on the presence of an abnormality between the clinical and 4D-DSA in 23/26 cases. In 2 cases, there were conflicting opinions. CONCLUSIONS In this study, the information content of 4D-DSA reconstructions was largely equivalent to that of the combined 2D/3D studies. The availability of 4D-DSA should reduce the requirement for 2D-DSA acquisitions.
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Affiliation(s)
| | - P Yang
- Department of Neurosurgery (P.Y.), Changhai Hospital, Second Military Medical University, Shanghai, China
| | | | - S Schafer
- Siemens Healthineers, USA (S.S.), Hoffman Estates, Illinois
| | - S Hetzel
- Biostatistics and Medical Informatics (S.H.), University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - A Ahmed
- From the Departments of Neurological Surgery (C.S.-G., A.A.)
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van Steenberghe M, Schubert T, Guiot Y, Bouzin C, Bollen X, Gianello P. Enhanced vascular biocompatibility of decellularized xeno-/allogeneic matrices in a rodent model. Cell Tissue Bank 2017; 18:249-262. [PMID: 28238108 DOI: 10.1007/s10561-017-9610-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 02/09/2017] [Indexed: 02/03/2023]
Abstract
Glutaraldehyde preservation is the gold standard for cardiovascular biological prosthesis. However, secondary calcifications and the absence of tissue growth remain major limitations. Our study assessed in vitro and in vivo the biocompatibility of human (fascia lata, pericardium) and porcine tissues (pericardium, peritoneum) treated with a physicochemical procedure for decellularization and non-conventional pathogens inactivation. Biopsies were performed before and after treatment to assess decellularization (HE/Dapi staining/DNA quantification/MHC I/alpha gal immunostaining) and mechanical integrity. Forty-five rats received an abdominal aortic patch of native cryopreserved tissues (n = 20), treated tissues (n = 20) or glutaraldehyde-preserved bovine pericardium (GBP, control, n = 5). Grafts were explanted at 4 weeks and processed for HE/von Kossa staining and immunohistochemistries for lymphocytes (CD3)/macrophages (CD68) histomorphometry. 95% of decellularization was obtained for all tissues except for fascia lata (75%). Mechanical properties were slightly altered. In the in vivo model, a significant increase of CD3 and CD68 infiltrations was found in native and control implants in comparison with decellularized tissues (p < 0.05). Calcifications were found in 3 controls. Decellularized tissues were recolonized. GBP showed the most inflammatory response. This physicochemical treatment improves the biocompatibility of selected xeno/allogeneic tissues in comparison with their respective native cryopreserved tissues and with GBP. Incomplete decellularization is associated with a significantly higher inflammatory response. Our treatment is a promising tool in the field of tissue decellularization and tissue banking.
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Affiliation(s)
- M van Steenberghe
- Secteur des Sciences de la Santé, Institut de Recherche Expérimentale et Clinique, Pôle de Chirurgie Expérimentale et Transplantation (CHEX), Université catholique de Louvain, Avenue Mounier 55, 1200, Brussels, Belgium. .,Cardiac Surgery Department, University Clinical Hospital (CHUV), Lausanne, Switzerland.
| | - T Schubert
- Secteur des Sciences de la Santé, Institut de Recherche Expérimentale et Clinique, Pôle de Chirurgie Expérimentale et Transplantation (CHEX), Université catholique de Louvain, Avenue Mounier 55, 1200, Brussels, Belgium.,Service d'orthopédie et de traumatologie de l'appareil locomoteur, Cliniques universitaires Saint-Luc, Avenue Hippocrate 10, 1200, Brussels, Belgium.,Unité de thérapie tissulaire et cellulaire de l'appareil locomoteur, Cliniques Universitaires Saint-Luc, Avenue Hippocrate 10, 1200, Brussels, Belgium
| | - Y Guiot
- Service d'anatomopathologie, Cliniques universitaires Saint-Luc, Avenue Hippocrate 10, 1200, Brussels, Belgium
| | - C Bouzin
- Secteur des Sciences de la Santé, Institut de Recherche Expérimentale et Clinique, Pôle de Pharmacologie et de Thérapeutique (FATH), Université catholique de Louvain, Avenue Mounier 52, 1200, Brussels, Belgium
| | - X Bollen
- Secteur des Sciences et Technologies, Institute of Mechanics, Materials and Civil Engineering, Centre de Recherche en Energie et Mécatronique (CEREM), Université catholique de Louvain, Place du Levant, 2 L5-04-01, 1348, Louvain-la-Neuve, Belgium
| | - P Gianello
- Secteur des Sciences de la Santé, Institut de Recherche Expérimentale et Clinique, Pôle de Chirurgie Expérimentale et Transplantation (CHEX), Université catholique de Louvain, Avenue Mounier 55, 1200, Brussels, Belgium
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Franke K, Berens P, Schubert T, Bethge M, Euler T, Baden T. Inhibition decorrelates visual feature representations in the inner retina. Nature 2017; 542:439-444. [PMID: 28178238 PMCID: PMC5325673 DOI: 10.1038/nature21394] [Citation(s) in RCA: 136] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 01/18/2017] [Indexed: 01/25/2023]
Abstract
The retina extracts visual features for transmission to the brain. Different types of bipolar cell split the photoreceptor input into parallel channels and provide the excitatory drive for downstream visual circuits. Anatomically and genetically, mouse bipolar cell types have been described at great detail, but a similarly deep understanding of their functional diversity is lacking. By imaging light-driven glutamate release from more than 13,000 bipolar cell axon terminals in the intact retina, we here show that bipolar cell functional diversity is generated by the interplay of dendritic excitatory inputs and axonal inhibitory inputs. The resultant centre and surround components of bipolar cell receptive fields interact to decorrelate bipolar cell output in the spatial and temporal domain. Our findings highlight the importance of inhibitory circuits in generating functionally diverse excitatory pathways and suggest that decorrelation of parallel visual pathways begins already at the second synapse of the mouse visual system.
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Affiliation(s)
- Katrin Franke
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.,Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Graduate School of Neural &Behavioural Sciences, International Max Planck Research School, University of Tübingen, Tübingen, Germany
| | - Philipp Berens
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.,Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Timm Schubert
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.,Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Matthias Bethge
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.,Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Institute for Theoretical Physics, University of Tübingen, Tübingen, Germany.,Max Planck Institute of Biological Cybernetics, Tübingen, Germany
| | - Thomas Euler
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.,Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Tom Baden
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.,Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany.,Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,School of Life Sciences, University of Sussex, Brighton, UK
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Behrens C, Schubert T, Haverkamp S, Euler T, Berens P. Connectivity map of bipolar cells and photoreceptors in the mouse retina. eLife 2016; 5:e20041. [PMID: 27885985 PMCID: PMC5148610 DOI: 10.7554/elife.20041] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 11/21/2016] [Indexed: 01/09/2023] Open
Abstract
In the mouse retina, three different types of photoreceptors provide input to 14 bipolar cell (BC) types. Classically, most BC types are thought to contact all cones within their dendritic field; ON-BCs would contact cones exclusively via so-called invaginating synapses, while OFF-BCs would form basal synapses. By mining publically available electron microscopy data, we discovered interesting violations of these rules of outer retinal connectivity: ON-BC type X contacted only ~20% of the cones in its dendritic field and made mostly atypical non-invaginating contacts. Types 5T, 5O and 8 also contacted fewer cones than expected. In addition, we found that rod BCs received input from cones, providing anatomical evidence that rod and cone pathways are interconnected in both directions. This suggests that the organization of the outer plexiform layer is more complex than classically thought.
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Affiliation(s)
- Christian Behrens
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany
- Graduate Training Center for Neuroscience, International Max Planck Research School, University of Tübingen, Tübingen, Germany
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Silke Haverkamp
- Institute of Cellular and Molecular Anatomy, Goethe-University Frankfurt, Frankfurt, Germany
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany
| | - Philipp Berens
- Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
- Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience, University of Tübingen, Tübingen, Germany
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Kulkarni M, Trifunović D, Schubert T, Euler T, Paquet-Durand F. Calcium dynamics change in degenerating cone photoreceptors. Hum Mol Genet 2016; 25:3729-3740. [PMID: 27402880 DOI: 10.1093/hmg/ddw219] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 06/24/2016] [Accepted: 06/25/2016] [Indexed: 11/14/2022] Open
Abstract
Cone photoreceptors (cones) are essential for high-resolution daylight vision and colour perception. Loss of cones in hereditary retinal diseases has a dramatic impact on human vision. The mechanisms underlying cone death are poorly understood, and consequently, there are no treatments available. Previous studies suggest a central role for calcium (Ca2+) homeostasis deficits in photoreceptor degeneration; however, direct evidence for this is scarce and physiological measurements of Ca2+ in degenerating mammalian cones are lacking.Here, we took advantage of the transgenic HR2.1:TN-XL mouse line that expresses a genetically encoded Ca2+ biosensor exclusively in cones. We cross-bred this line with mouse models for primary ("cone photoreceptor function loss-1", cpfl1) and secondary ("retinal degeneration-1", rd1) cone degeneration, respectively, and assessed resting Ca2+ levels and light-evoked Ca2+ responses in cones using two-photon imaging. We found that Ca2+ dynamics were altered in cpfl1 cones, showing higher noise and variable Ca2+ levels, with significantly wider distribution than for wild-type and rd1 cones. Unexpectedly, up to 21% of cpfl1 cones still displayed light-evoked Ca2+ responses, which were larger and slower than wild-type responses. In contrast, genetically intact rd1 cones were characterized by lower noise and complete lack of visual function.Our study demonstrates alterations in cone Ca2+ dynamics in both primary and secondary cone degeneration. Our results are consistent with the view that higher (fluctuating) cone Ca2+ levels are involved in photoreceptor cell death in primary (cpfl1) but not in secondary (rd1) cone degeneration. These findings may guide the future development of therapies targeting photoreceptor Ca2+ homeostasis.
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Affiliation(s)
- Manoj Kulkarni
- Institute for Ophthalmic Research.,Werner Reichardt Centre for Integrative Neuroscience.,Graduate School of Cellular & Molecular Neuroscience
| | | | - Timm Schubert
- Institute for Ophthalmic Research.,Werner Reichardt Centre for Integrative Neuroscience
| | - Thomas Euler
- Institute for Ophthalmic Research (F.P-D.) (T.E.).,Werner Reichardt Centre for Integrative Neuroscience.,Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
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Simakova IL, Demidova YS, Gläsel J, Murzina EV, Schubert T, Prosvirin IP, Etzold BJM, Murzin DY. Controlled synthesis of PVP-based carbon-supported Ru nanoparticles: synthesis approaches, characterization, capping agent removal and catalytic behavior. Catal Sci Technol 2016. [DOI: 10.1039/c6cy02086k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
PVP-capped Ru nanoparticles were synthesized, immobilized on several carbon supports and tested in galactose hydrogenation.
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Affiliation(s)
- I. L. Simakova
- Boreskov Institute of Catalysis
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
| | - Yu. S. Demidova
- Boreskov Institute of Catalysis
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
| | - J. Gläsel
- Technische Universität Darmstadt
- Ernst-Berl-Institut für Technische und Makromolekulare Chemie
- Darmstadt
- Germany
| | | | | | | | - B. J. M. Etzold
- Technische Universität Darmstadt
- Ernst-Berl-Institut für Technische und Makromolekulare Chemie
- Darmstadt
- Germany
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Abstract
During neuronal degenerative diseases, microcircuits undergo severe structural alterations, leading to remodeling of synaptic connectivity. This can be particularly well observed in the retina, where photoreceptor degeneration triggers rewiring of connections in the retina’s first synaptic layer (e.g., Strettoi et al., 2003; Haq et al., 2014), while the synaptic organization of inner retinal circuits appears to be little affected (O’Brien et al., 2014; Figures 1A,B). Remodeling of (outer) retinal circuits and diminishing light-driven activity due to the loss of functional photoreceptors lead to spontaneous activity that can be observed at different retinal levels (Figure 1C), including the retinal ganglion cells, which display rhythmic spiking activity in the degenerative retina (Margolis et al., 2008; Stasheff, 2008; Menzler and Zeck, 2011; Stasheff et al., 2011). Two networks have been suggested to drive the oscillatory activity in the degenerating retina: a network of remnant cone photoreceptors, rod bipolar cells (RBCs) and horizontal cells in the outer retina (Haq et al., 2014), and the AII amacrine cell-cone bipolar cell network in the inner retina (Borowska et al., 2011). Notably, spontaneous rhythmic activity in the inner retinal network can be triggered in the absence of synaptic remodeling in the outer retina, for example, in the healthy retina after photo-bleaching (Menzler et al., 2014). In addition, the two networks show remarkable differences in their dominant oscillation frequency range as well as in the types and numbers of involved cells (Menzler and Zeck, 2011; Haq et al., 2014). Taken together this suggests that the two networks are self-sustained and can be active independently from each other. However, it is not known if and how they modulate each other. In this mini review, we will discuss: (i) commonalities and differences between these two oscillatory networks as well as possible interaction pathways; (ii) how multiple self-sustained networks may hamper visual restoration strategies employing, for example, microelectronic implants, optogenetics or stem cells, and briefly; and (iii) how the finding of diverse (independent) networks in the degenerative retina may relate to other parts of the neurodegenerative central nervous system.
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Affiliation(s)
- Thomas Euler
- Werner Reichardt Centre for Integrative Neuroscience (CIN)/Institute for Ophathalmic Research, University of Tübingen Tübingen, Germany ; Bernstein Centre for Computational Neuroscience, University of Tübingen Tübingen, Germany
| | - Timm Schubert
- Werner Reichardt Centre for Integrative Neuroscience (CIN)/Institute for Ophathalmic Research, University of Tübingen Tübingen, Germany
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34
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Abstract
Synaptic disorganization is a prominent feature of many neurological diseases of the CNS, including Parkinson's disease, intellectual development disorders, and autism. Although synaptic plasticity is critical for learning and memory, it is unclear whether this innate property helps restore synaptic function in disease once the primary cause of disease is abrogated. An answer to this question may come from a recent investigation in X-linked retinoschisis, a currently untreatable retinopathy. In this issue of the JCI, Ou, Vijayasarathy, and colleagues showed progressive disorganization of key functional elements of the synapse between photoreceptors and ON-bipolar cells in a retinoschisin-deficient mouse model. Moreover, they demonstrated that adeno-associated virus-mediated (AAV-mediated) delivery of the retinoschisin gene restores structure and function to the photoreceptor to ON-bipolar cell synapse in mouse models, even in adults at advanced stages of the disease. The results of this study hold promise that AAV-based supplemental gene therapy will benefit patients with X-linked retinoschisis in a forthcoming clinical trial.
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Gakis G, Morgan TM, Daneshmand S, Keegan KA, Todenhöfer T, Mischinger J, Schubert T, Zaid HB, Hrbacek J, Ali-El-Dein B, Clayman RH, Galland S, Olugbade K, Rink M, Fritsche HM, Burger M, Chang SS, Babjuk M, Thalmann GN, Stenzl A, Efstathiou JA. Impact of perioperative chemotherapy on survival in patients with advanced primary urethral cancer: results of the international collaboration on primary urethral carcinoma. Ann Oncol 2015; 26:1754-9. [PMID: 25969370 DOI: 10.1093/annonc/mdv230] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Accepted: 05/06/2015] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND To investigate the impact of perioperative chemo(radio)therapy in advanced primary urethral carcinoma (PUC). PATIENTS AND METHODS A series of 124 patients (86 men, 38 women) were diagnosed with and underwent surgery for PUC in 10 referral centers between 1993 and 2012. Kaplan-Meier analysis with log-rank testing was used to investigate the impact of perioperative chemo(radio)therapy on overall survival (OS). The median follow-up was 21 months (mean: 32 months; interquartile range: 5-48). RESULTS Neoadjuvant chemotherapy (NAC), neoadjuvant chemoradiotherapy (N-CRT) plus adjuvant chemotherapy (ACH), and ACH was delivered in 12 (31%), 6 (15%) and 21 (54%) of these patients, respectively. Receipt of NAC/N-CRT was associated with clinically node-positive disease (cN+; P = 0.033) and lower utilization of cystectomy at surgery (P = 0.015). The objective response rate to NAC and N-CRT was 25% and 33%, respectively. The 3-year OS for patients with objective response to neoadjuvant treatment (complete/partial response) was 100% and 58.3% for those with stable or progressive disease (P = 0.30). Of the 26 patients staged ≥cT3 and/or cN+ disease, 16 (62%) received perioperative chemo(radio)therapy and 10 upfront surgery without perioperative chemotherapy (38%). The 3-year OS for this locally advanced subset of patients (≥cT3 and/or cN+) who received NAC (N = 5), N-CRT (N = 3), surgery-only (N = 10) and surgery plus ACH (N = 8) was 100%, 100%, 50% and 20%, respectively (P = 0.016). Among these 26 patients, receipt of neoadjuvant treatment was significantly associated with improved 3-year relapse-free survival (RFS) (P = 0.022) and OS (P = 0.022). Proximal tumor location correlated with inferior 3-year RFS and OS (P = 0.056/0.005). CONCLUSION In this series, patients who received NAC/N-CRT for cT3 and/or cN+ PUC appeared to demonstrate improved survival compared with those who underwent upfront surgery with or without ACH.
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Affiliation(s)
- G Gakis
- Department of Urology, University of Tuebingen, Tuebingen, Germany
| | - T M Morgan
- Department of Urology, University of Michigan, Ann Arbor, USA
| | - S Daneshmand
- Institute of Urology, USC/Norris Comprehensive Cancer Center, Los Angeles
| | - K A Keegan
- Department of Urologic Surgery, Vanderbilt University Medical Center, Nashville, USA
| | - T Todenhöfer
- Department of Urology, University of Tuebingen, Tuebingen, Germany
| | - J Mischinger
- Department of Urology, University of Tuebingen, Tuebingen, Germany
| | - T Schubert
- Department of Urology, University of Tuebingen, Tuebingen, Germany
| | - H B Zaid
- Department of Urologic Surgery, Vanderbilt University Medical Center, Nashville, USA
| | - J Hrbacek
- 2nd Medical School, Department of Urology, Charles University, Prague, Czech Republic
| | - B Ali-El-Dein
- Urology and Nephrology Center, Mansoura Clinic, Mansoura, Egypt
| | - R H Clayman
- Department of Radiooncology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - S Galland
- Department of Radiooncology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - K Olugbade
- Department of Urology, University of Michigan, Ann Arbor, USA
| | - M Rink
- Department of Urology, University Medical Center Hamburg-Eppendorf, Hamburg
| | - H-M Fritsche
- Department of Urology, University Hospital Regensburg, Regensburg, Germany
| | - M Burger
- Department of Urology, University Hospital Regensburg, Regensburg, Germany
| | - S S Chang
- Department of Urologic Surgery, Vanderbilt University Medical Center, Nashville, USA
| | - M Babjuk
- 2nd Medical School, Department of Urology, Charles University, Prague, Czech Republic
| | - G N Thalmann
- Department of Urology, University Hospital Bern, Bern, Switzerland
| | - A Stenzl
- Department of Urology, University of Tuebingen, Tuebingen, Germany
| | - J A Efstathiou
- Department of Radiooncology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
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36
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Kulkarni M, Schubert T, Baden T, Wissinger B, Euler T, Paquet-Durand F. Imaging Ca2+ dynamics in cone photoreceptor axon terminals of the mouse retina. J Vis Exp 2015:e52588. [PMID: 25993489 PMCID: PMC4542458 DOI: 10.3791/52588] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Retinal cone photoreceptors (cones) serve daylight vision and are the basis of color discrimination. They are subject to degeneration, often leading to blindness in many retinal diseases. Calcium (Ca2+), a key second messenger in photoreceptor signaling and metabolism, has been proposed to be indirectly linked with photoreceptor degeneration in various animal models. Systematically studying these aspects of cone physiology and pathophysiology has been hampered by the difficulties of electrically recording from these small cells, in particular in the mouse where the retina is dominated by rod photoreceptors. To circumvent this issue, we established a two-photon Ca2+ imaging protocol using a transgenic mouse line that expresses the genetically encoded Ca2+ biosensor TN-XL exclusively in cones and can be crossbred with mouse models for photoreceptor degeneration. The protocol described here involves preparing vertical sections (“slices”) of retinas from mice and optical imaging of light stimulus-evoked changes in cone Ca2+ level. The protocol also allows “in-slice measurement” of absolute Ca2+ concentrations; as the recordings can be followed by calibration. This protocol enables studies into functional cone properties and is expected to contribute to the understanding of cone Ca2+ signaling as well as the potential involvement of Ca2+ in photoreceptor death and retinal degeneration.
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Affiliation(s)
- Manoj Kulkarni
- Institute for Ophthalmic Research, University of Tübingen; Graduate School of Cellular & Molecular Neuroscience, University of Tübingen
| | - Timm Schubert
- Institute for Ophthalmic Research, University of Tübingen; Bernstein Centre for Computational Neuroscience, University of Tübingen
| | - Tom Baden
- Institute for Ophthalmic Research, University of Tübingen; Graduate School of Cellular & Molecular Neuroscience, University of Tübingen; Bernstein Centre for Computational Neuroscience, University of Tübingen
| | - Bernd Wissinger
- Molecular Genetics Laboratory, University of Tübingen; Centre for Ophthalmology, University of Tübingen
| | - Thomas Euler
- Institute for Ophthalmic Research, University of Tübingen; Graduate School of Cellular & Molecular Neuroscience, University of Tübingen; Bernstein Centre for Computational Neuroscience, University of Tübingen;
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Lee SCS, Meyer A, Schubert T, Hüser L, Dedek K, Haverkamp S. Morphology and connectivity of the small bistratified A8 amacrine cell in the mouse retina. J Comp Neurol 2015; 523:1529-47. [PMID: 25630271 DOI: 10.1002/cne.23752] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 01/22/2015] [Accepted: 01/24/2015] [Indexed: 01/23/2023]
Abstract
Amacrine cells comprise ∼ 30 morphological types in the mammalian retina. The synaptic connectivity and function of a few γ-aminobutyric acid (GABA)ergic wide-field amacrine cells have recently been studied; however, with the exception of the rod pathway-specific AII amacrine cell, the connectivity of glycinergic small-field amacrine cells has not been investigated in the mouse retina. Here, we studied the morphology and connectivity pattern of the small-field A8 amacrine cell. A8 cells in mouse retina are bistratified with lobular processes in the ON sublamina and arboreal dendrites in the OFF sublamina of the inner plexiform layer. The distinct bistratified morphology was first visible at postnatal day 8, reaching the adult shape at P13, around eye opening. The connectivity of A8 cells to bipolar cells and ganglion cells was studied by double and triple immunolabeling experiments by using various cell markers combined with synaptic markers. Our data suggest that A8 amacrine cells receive glutamatergic input from both OFF and ON cone bipolar cells. Furthermore, A8 cells are coupled to ON cone bipolar cells by gap junctions, and provide inhibitory input via glycine receptor (GlyR) subunit α1 to OFF cone bipolar cells and to ON A-type ganglion cells. Measurements of spontaneous glycinergic postsynaptic currents and GlyR immunolabeling revealed that A8 cells express GlyRs containing the α2 subunit. The results show that the bistratified A8 cell makes very similar synaptic contacts with cone bipolar cells as the rod pathway-specific AII amacrine cell. However, unlike AII cells, A8 amacrine cells provide glycinergic input to ON A-type ganglion cells.
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Affiliation(s)
- Sammy C S Lee
- Max Planck Institute for Brain Research, 60438, Frankfurt am Main, Germany.,University of Sydney-Save Sight Institute, Sydney, New South Wales, 2000, Australia
| | - Arndt Meyer
- Department of Neurobiology, University of Oldenburg, 26129, Oldenburg, Germany
| | - Timm Schubert
- Werner Reichardt Center for Integrative Neuroscience (CIN)/Institute for Ophthalmic Research, University of Tübingen, 72076, Tübingen, Germany
| | - Laura Hüser
- Max Planck Institute for Brain Research, 60438, Frankfurt am Main, Germany
| | - Karin Dedek
- Department of Neurobiology, University of Oldenburg, 26129, Oldenburg, Germany.,Research Center for Neurosensory Science, University of Oldenburg, 26129, Oldenburg, Germany
| | - Silke Haverkamp
- Max Planck Institute for Brain Research, 60438, Frankfurt am Main, Germany
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Schubert T, Pansini M, Bieri O, Stippich C, Wetzel S, Schaedelin S, von Hessling A, Santini F. Attenuation of blood flow pulsatility along the Atlas slope: a physiologic property of the distal vertebral artery? AJNR Am J Neuroradiol 2015; 36:562-7. [PMID: 25395658 DOI: 10.3174/ajnr.a4148] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Physiologic and pathologic arterial tortuosity may attenuate blood flow pulsatility. The aim of this prospective study was to assess a potential effect of the curved V3 segment (Atlas slope) of the vertebral artery on arterial flow pulsatility. The pulsatility index and resistance index were used to assess blood flow pulsatility. MATERIALS AND METHODS Twenty-one healthy volunteers (17 men, 4 women; mean age, 32 years) were examined with a 3T MR imaging system. Blood velocities were measured at 2 locations below (I and II) and at 1 location above the V3 segment (III) of the vertebral artery by using a high-resolution 2D-phase-contrast sequence with multidirectional velocity-encoding. RESULTS Pulsatility and resistance indices decreased along all measurement locations from proximal to distal. The pulsatility index decreased significantly from location II to III and from I to II. However, the decrease was more pronounced along the Atlas slope than in the straight-vessel section below. The decrease of the resistance index was highly significant along the Atlas slope (location II to III). The decrease from location I to II was small and not significant. CONCLUSIONS The pronounced decrease in pulsatility and resistance indices along the interindividually uniformly bent V3 segment compared with a straight segment of the vertebral artery indicates a physiologic attenuating effect of the Atlas slope on arterial flow pulsatility. A similar effect has been described for the carotid siphon. A physiologic reduction of pulsatility in brain-supplying arteries would be in accordance with several recent publications reporting a correlation of increased arterial flow pulsatility with leukoencephalopathy and lacunar stroke.
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Affiliation(s)
- T Schubert
- From the Divisions of Neuroradiology (T.S., C.S., A.v.H.)
| | - M Pansini
- Department of Radiology (M.P.), Bruderholz Cantonal Hospital, Basel, Switzerland
| | - O Bieri
- Radiological Physics (O.B., F.S.), Clinic of Radiology and Nuclear Medicine
| | - C Stippich
- From the Divisions of Neuroradiology (T.S., C.S., A.v.H.)
| | - S Wetzel
- Department of Neuroradiology (S.W.), Hirslanden Clinic, Zurich, Switzerland
| | - S Schaedelin
- Clinical Trial Unit (S.S.), Basel University Hospital, Basel, Switzerland
| | - A von Hessling
- From the Divisions of Neuroradiology (T.S., C.S., A.v.H.)
| | - F Santini
- Radiological Physics (O.B., F.S.), Clinic of Radiology and Nuclear Medicine
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Rieken M, Schubert T, Xylinas E, Kluth L, Rouprêt M, Trinh QD, Lee R, Al Hussein Al Awamlh B, Fajkovic H, Novara G, Margulis V, Lotan Y, Martinez-Salamanca J, Matsumoto K, Seitz C, Remzi M, Karakiewicz P, Scherr D, Briganti A, Bachmann A, Shariat S. Association of perioperative blood transfusion with oncologic outcomes after radical nephroureterectomy for upper tract urothelial carcinoma. Eur J Surg Oncol 2014; 40:1693-9. [DOI: 10.1016/j.ejso.2014.03.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 03/16/2014] [Accepted: 03/20/2014] [Indexed: 12/24/2022] Open
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40
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Babu B, Dankers H, Newberry E, Baker C, Schubert T, Knox G, Paret M. First Report of Rose rosette virus Associated with Rose Rosette Disease Infecting Knockout Roses in Florida. Plant Dis 2014; 98:1449. [PMID: 30703988 DOI: 10.1094/pdis-05-14-0501-pdn] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Roses are one of the most popular flowering shrubs in the United States, with a total wholesale value of US$194 million. Among the major states, Florida is the fourth largest producer of roses with a total value exceeding US$20 million (4). In Florida, the roses have become especially popular in recent years with the introduction of Knock Out and other shrub roses. Virus-like symptoms including witches'-broom, excessive thorns, abnormal red discoloration of shoots and foliages, distorted leaves, and deformed buds and flowers were initially observed on Knock Out roses in a commercial nursery in Quincy, FL, in November 2013. Fifteen plants out of ~250,000 plants showed these characteristic symptoms. Total RNA extracts (RNeasy Plant Mini Kit, Qiagen, Valencia, CA) from eight symptomatic and two non-symptomatic rose samples were subjected to reverse-transcription (RT) assays using SuperScript III Reverse transcriptase (Invitrogen, Life Technologies, NY) and random hexamer primers. The cDNA synthesized was then subjected to PCR assay using Platinum Taq DNA polymerase (Invitrogen, Life Technologies) and using Rose rosette virus (RRV) specific primers RRV-F and RRV-R (1), targeting the core region of the RNA1 genome of the virus. The RT-PCR assays using the specific primers produced amplicons of 375 bp, only in the symptomatic leaf samples. The obtained amplicons were PCR purified and sequenced directly (GenBank Accession Nos. KF990370 to KF990377). BLAST analysis of these sequences revealed a higher identity of 99% with the RRV (HQ871942) in the NCBI database. Pairwise comparison of the eight RRV sequences exhibited 99 to 100% identity among themselves. These results revealed the association of RRV with the symptomatic rose plants. Eight symptomatic and two non-symptomatic rose plant samples were tested for RRV using blot hybridization assay, utilizing a digoxigenin-labeled DNA probe of 511 bp, targeting the RNA1 genome of the RRV. All eight symptomatic rose plants showed a positive reaction to the RRV-specific probes, confirming the presence of RRV in the samples, while the non-symptomatic and the buffer control did not produce any reactions. Even though the virus is reported to spread by an eriophyid mite Phyllocoptes fructiphilus, thorough examination of the infected samples showed absence of the vector. The samples were also tested using RT-PCR for the presence of Rose cryptic virus (RCV) and Blackberry chlorotic ringspot virus (BCRV) using specific primers (2,3). The samples tested negative for the RCV and BCRV. This is the first report of occurrence of RRV on rose in Florida. Considering the economic importance of the rose plants and the highly destructive nature of RRV, this report underscores the need for immediate effective quarantine and management of the virus for protecting the economically important rose industry in Florida. References: (1) A. G. Laney et al. J. Gen. Virol. 92:1727, 2011. (2) S. Sabanadzovic and N. Abou Ghanem-Sabanadzovic. J. Plant Pathol. 90:287, 2008. (3) I. E. Tzanetakis et al. Plant Pathol. 55:568, 2006. (4) USDA. 2007 Census of Agriculture 3:25, Washington, DC, 2010.
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Affiliation(s)
- B Babu
- North Florida Research and Education Center, University of Florida, Quincy 32351
| | - H Dankers
- North Florida Research and Education Center, University of Florida, Quincy 32351
| | - E Newberry
- North Florida Research and Education Center, University of Florida, Quincy 32351
| | - C Baker
- Division of Plant Industry, Florida Department of Agriculture and Consumer Services, Gainesville, FL 32608
| | - T Schubert
- Division of Plant Industry, Florida Department of Agriculture and Consumer Services, Gainesville, FL 32608
| | - G Knox
- North Florida Research and Education Center, University of Florida, Quincy 32351
| | - M Paret
- North Florida Research and Education Center, University of Florida, Quincy 32351
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Haq W, Arango-Gonzalez B, Zrenner E, Euler T, Schubert T. Synaptic remodeling generates synchronous oscillations in the degenerated outer mouse retina. Front Neural Circuits 2014; 8:108. [PMID: 25249942 PMCID: PMC4155782 DOI: 10.3389/fncir.2014.00108] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 08/19/2014] [Indexed: 11/28/2022] Open
Abstract
During neuronal degenerative diseases, neuronal microcircuits undergo severe structural alterations, leading to remodeling of synaptic connectivity. The functional consequences of such remodeling are mostly unknown. For instance, in mutant rd1 mouse retina, a common model for Retinitis Pigmentosa, rod bipolar cells (RBCs) establish contacts with remnant cone photoreceptors (cones) as a consequence of rod photoreceptor cell death and the resulting lack of presynaptic input. To assess the functional connectivity in the remodeled, light-insensitive outer rd1 retina, we recorded spontaneous population activity in retinal wholemounts using Ca(2+) imaging and identified the participating cell types. Focusing on cones, RBCs and horizontal cells (HCs), we found that these cell types display spontaneous oscillatory activity and form synchronously active clusters. Overall activity was modulated by GABAergic inhibition from interneurons such as HCs and/or possibly interplexiform cells. Many of the activity clusters comprised both cones and RBCs. Opposite to what is expected from the intact (wild-type) cone-ON bipolar cell pathway, cone and RBC activity was positively correlated and, at least partially, mediated by glutamate transporters expressed on RBCs. Deletion of gap junctional coupling between cones reduced the number of clusters, indicating that electrical cone coupling plays a crucial role for generating the observed synchronized oscillations. In conclusion, degeneration-induced synaptic remodeling of the rd1 retina results in a complex self-sustained outer retinal oscillatory network, that complements (and potentially modulates) the recently described inner retinal oscillatory network consisting of amacrine, bipolar and ganglion cells.
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Affiliation(s)
- Wadood Haq
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of TübingenTübingen, Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of TübingenTübingen, Germany
- Bernstein Center for Computational Neuroscience Tübingen, University of TübingenTübingen, Germany
| | - Blanca Arango-Gonzalez
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of TübingenTübingen, Germany
| | - Eberhart Zrenner
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of TübingenTübingen, Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of TübingenTübingen, Germany
- Bernstein Center for Computational Neuroscience Tübingen, University of TübingenTübingen, Germany
| | - Thomas Euler
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of TübingenTübingen, Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of TübingenTübingen, Germany
- Bernstein Center for Computational Neuroscience Tübingen, University of TübingenTübingen, Germany
| | - Timm Schubert
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of TübingenTübingen, Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of TübingenTübingen, Germany
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Gaschler R, Schwager S, Umbach VJ, Frensch PA, Schubert T. Expectation mismatch: differences between self-generated and cue-induced expectations. Neurosci Biobehav Rev 2014; 46 Pt 1:139-57. [PMID: 24971824 DOI: 10.1016/j.neubiorev.2014.06.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Revised: 05/20/2014] [Accepted: 06/17/2014] [Indexed: 11/19/2022]
Abstract
Expectation of upcoming stimuli and tasks can lead to improved performance, if the anticipated situation occurs, while expectation mismatch can lead to less efficient processing. Researchers have used methodological approaches that rely on either self-generated expectations (predictions) or cue-induced expectations to investigate expectation mismatch effects. Differentiating these two types of expectations for different contents of expectation such as stimuli, responses, task sets and conflict level, we review evidence suggesting that self-generated expectations lead to larger facilitating effects and conflict effects on the behavioral and neural level - as compared to cue-based expectations. On a methodological level, we suggest that self-generated as compared to cue-induced expectations allow for a higher amount of experimental control in many experimental designs on expectation effects. On a theoretical level, we argue for qualitative differences in how cues vs. self-generated expectations influence performance. While self-generated expectations might generally involve representing the expected event in the focus of attention in working memory, cues might only lead to such representations under supportive circumstances (i.e., cue of high validity and attended).
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Peters RK, Schubert T, Clemmons R, Vickroy T. Levetiracetam rectal administration in healthy dogs. J Vet Intern Med 2014; 28:504-9. [PMID: 24417468 PMCID: PMC4857990 DOI: 10.1111/jvim.12269] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 09/24/2013] [Accepted: 11/05/2013] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Levetiracetam is used to manage status epilepticus (SE) and cluster seizures (CS) in humans. The drug might be absorbed after rectal administration and could offer a practical adjunct to rectal administration of diazepam in managing SE and CS. HYPOTHESIS Levetiracetam is rapidly absorbed after rectal administration in dogs and maintains target serum concentrations for at least 9 hours. ANIMALS Six healthy privately owned dogs between 2 and 6 years of age and weighing 10-20 kg. METHODS Levetiracetam (40 mg/kg) was administered rectally and blood samples were obtained immediately before (time zero) and at 10, 20, 40, 60, 90, 180, 360, and 540 minutes after drug administration. Dogs were observed for signs of adverse effects over a 24-hour period after drug administration. RESULTS CLEV at 10 minutes was 15.3 ± 5.5 μg/mL (mean, SD) with concentrations in the target range (5-40 μg/mL) for all dogs throughout the sampling period. Cmax (36.0 ± 10.7 μg/mL) and Tmax (103 ± 31 minutes) values were calculated and 2 disparate groups were appreciated. Dogs with feces in the rectum at the time of drug administration had lower mean Cmax values (26.7 ± 3.4 μg/mL) compared with those without (45.2 ± 4.4 μg/mL). Mild sedation was observed between 60 and 90 minutes without other adverse effects noted. CONCLUSIONS AND CLINICAL IMPORTANCE This study supports the use of rectally administered levetiracetam in future studies of clinical effectiveness in the management of epileptic dogs.
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Affiliation(s)
- R K Peters
- Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL
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Baden T, Schubert T, Chang L, Wei T, Zaichuk M, Wissinger B, Euler T. A Tale of Two Retinal Domains: Near-Optimal Sampling of Achromatic Contrasts in Natural Scenes through Asymmetric Photoreceptor Distribution. Neuron 2013; 80:1206-17. [DOI: 10.1016/j.neuron.2013.09.030] [Citation(s) in RCA: 136] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/03/2013] [Indexed: 01/10/2023]
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45
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Schubert T, Rapp B, McCloskey M. Recognition of Oral Spelling is Diagnostic of the Integrity of the Central Reading Processes. ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.sbspro.2013.09.078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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46
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Hoeller U, Mueller T, Schubert T, Mehl S, Haase O, Trefzer U. Treatment Planning for Merkel Cell Carcinoma Based on the Relapse Pattern. Int J Radiat Oncol Biol Phys 2013. [DOI: 10.1016/j.ijrobp.2013.06.171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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47
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Schubert T, Rothlein D, Brothers T, LeDoux K, Gordon B, McCloskey M. High-level visual processing despite lack of awareness: Evidence from event-related potentials in a case of selective metamorphopsia. J Vis 2013. [DOI: 10.1167/13.9.1106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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48
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Wei P, Szameitat AJ, Müller HJ, Schubert T, Zhou X. The neural correlates of perceptual load induced attentional selection: an fMRI study. Neuroscience 2013; 250:372-80. [PMID: 23876324 DOI: 10.1016/j.neuroscience.2013.07.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 06/05/2013] [Accepted: 07/11/2013] [Indexed: 01/28/2023]
Abstract
The neural correlates of perceptual load induced attentional selection were investigated in an functional magnetic resonance imaging (fMRI) experiment in which attentional selection was manipulated through the variation of perceptual load in target search. Participants searched for a vertically or horizontally oriented bar among heterogeneously (the high load condition) or homogeneously (the low load condition) oriented distractor bars in the central display, which was flanked by a vertical or horizontal bar presented at the left or the right periphery. The search reaction times were longer when the central display was of high load than of low load, and were longer when the flanker was incongruent than congruent with the target. Importantly, the flanker congruency effect was manifested only in the low load condition, not in the high load condition, indicating that the perceptual load in target search determined whether the task-irrelevant flanker was processed. Imaging analyses revealed a set of fronto-parietal regions having higher activations in the high than in the low load condition. Anterior cingulate cortex (ACC) was more activated for the incongruent than for the congruent trials. Moreover, ACC and bilateral anterior insula were sensitive to the interaction between perceptual load and flanker congruency such that the activation differences between the incongruent and congruent conditions were significant in the low, but not in the high load condition. These results are consistent with the claim that ACC and bilateral anterior insula may exert executive control by selectively biasing processing in favor of task-relevant information and this biasing depends on the resources currently available to the control system.
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Affiliation(s)
- P Wei
- Beijing Key Laboratory of Learning and Cognition and Department of Psychology, Capital Normal University, Beijing 100048, China; Department of Psychology, LMU München, D-80802 München, Germany; Center for Brain and Cognition Sciences and Department of Psychology, Peking University, Beijing 100871, China.
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49
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Schubert T, Hoon M, Euler T, Lukasiewicz PD, Wong ROL. Developmental regulation and activity-dependent maintenance of GABAergic presynaptic inhibition onto rod bipolar cell axonal terminals. Neuron 2013; 78:124-37. [PMID: 23583111 DOI: 10.1016/j.neuron.2013.01.037] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/29/2013] [Indexed: 01/12/2023]
Abstract
Presynaptic inhibition onto axons regulates neuronal output, but how such inhibitory synapses develop and are maintained in vivo remains unclear. Axon terminals of glutamatergic retinal rod bipolar cells (RBCs) receive GABAA and GABAC receptor-mediated synaptic inhibition. We found that perturbing GABAergic or glutamatergic neurotransmission does not prevent GABAergic synaptogenesis onto RBC axons. But, GABA release is necessary for maintaining axonal GABA receptors. This activity-dependent process is receptor subtype specific: GABAC receptors are maintained, whereas GABAA receptors containing α1, but not α3, subunits decrease over time in mice with deficient GABA synthesis. GABAA receptor distribution on RBC axons is unaffected in GABAC receptor knockout mice. Thus, GABAA and GABAC receptor maintenance are regulated separately. Although immature RBCs elevate their glutamate release when GABA synthesis is impaired, homeostatic mechanisms ensure that the RBC output operates within its normal range after eye opening, perhaps to regain proper visual processing within the scotopic pathway.
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Affiliation(s)
- Timm Schubert
- Department of Biological Structure, University of Washington, School of Medicine, 1959 Northeast Pacific Street, Seattle, WA 98195, USA
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50
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Puller C, Ivanova E, Euler T, Haverkamp S, Schubert T. OFF bipolar cells express distinct types of dendritic glutamate receptors in the mouse retina. Neuroscience 2013; 243:136-48. [PMID: 23567811 DOI: 10.1016/j.neuroscience.2013.03.054] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 03/25/2013] [Accepted: 03/26/2013] [Indexed: 12/22/2022]
Abstract
Parallel representations of the visual world are already established at the very first synapse of the visual system. Cone photoreceptors, which hyperpolarize in response to light, forward the visual signal onto distinct types of ON and OFF cone bipolar cells (BCs). In the case of OFF BCs, the glutamatergic cone input is integrated by ionotropic glutamate receptors, giving rise to a sign-preserving mode of synaptic transmission. The combination of glutamate receptor (GluR) subunits, i.e. AMPA or kainate subunits, importantly contributes to shaping the OFF bipolar cells' distinct response properties. The mouse is one of the few mammals in which the (most likely) complete set of (five) retinal OFF BC types is identified. However, it is not clear which GluR subtypes are expressed by the different mouse OFF BC types. We addressed this question by combining immunolabeling, electrical whole-cell recordings and pharmacology, and present evidence that the different types of OFF BCs express distinct types of glutamate receptors: Type 1 BCs exclusively expressed AMPA receptors, whereas type 2 and type 3a BCs expressed kainate receptors of different subunit compositions. Additionally, we found that two OFF BC types (3b and 4) very likely express both AMPA and kainate receptors but, interestingly, the two receptor subunits were not co-localized at the same dendritic site. The complex, BC type-specific expression pattern of GluRs we describe here supports their essential role in establishing parallel pathways at the first synapse of the mouse visual system.
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Affiliation(s)
- C Puller
- Department of Neuroanatomy, Max Planck Institute for Brain Research, Frankfurt am Main, Germany.
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