21 results on '"Groos D"'
Search Results
2. Approaching human precision on automatic markerless tracking of human movements
- Author
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Groos, D., primary, Adde, L., additional, and Ihlen, E., additional
- Published
- 2020
- Full Text
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3. Anonymised Data and the Rule of Law
- Author
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Groos, D., primary and van Veen, E., additional
- Published
- 2020
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4. Die langstreckige Spondylodese bei degenerativen Wirbelsäulenerkrankungen: mittelfristige klinisch/radiologische Ergebnisse und Komplikationen
- Author
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Röllinghoff, M, Groos, D, Sobottke, R, Delank, KS, and Eysel, P
- Subjects
ddc: 610 - Published
- 2008
5. The lateral habenula: A hub for value-guided behavior.
- Author
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Groos D and Helmchen F
- Subjects
- Animals, Humans, Neurons physiology, Decision Making physiology, Habenula physiology
- Abstract
The habenula is an evolutionarily highly conserved diencephalic brain region divided into two major parts, medial and lateral. Over the past two decades, studies of the lateral habenula (LHb), in particular, have identified key functions in value-guided behavior in health and disease. In this review, we focus on recent insights into LHb connectivity and its functional relevance for different types of aversive and appetitive value-guided behavior. First, we give an overview of the anatomical organization of the LHb and its main cellular composition. Next, we elaborate on how distinct LHb neuronal subpopulations encode aversive and appetitive stimuli and on their involvement in more complex decision-making processes. Finally, we scrutinize the afferent and efferent connections of the LHb and discuss their functional implications for LHb-dependent behavior. A deepened understanding of distinct LHb circuit components will substantially contribute to our knowledge of value-guided behavior., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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6. Benchtop mesoSPIM: a next-generation open-source light-sheet microscope for cleared samples.
- Author
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Vladimirov N, Voigt FF, Naert T, Araujo GR, Cai R, Reuss AM, Zhao S, Schmid P, Hildebrand S, Schaettin M, Groos D, Mateos JM, Bethge P, Yamamoto T, Aerne V, Roebroeck A, Ertürk A, Aguzzi A, Ziegler U, Stoeckli E, Baudis L, Lienkamp SS, and Helmchen F
- Subjects
- Microscopy methods, Neurosciences
- Abstract
In 2015, we launched the mesoSPIM initiative, an open-source project for making light-sheet microscopy of large cleared tissues more accessible. Meanwhile, the demand for imaging larger samples at higher speed and resolution has increased, requiring major improvements in the capabilities of such microscopes. Here, we introduce the next-generation mesoSPIM ("Benchtop") with a significantly increased field of view, improved resolution, higher throughput, more affordable cost, and simpler assembly compared to the original version. We develop an optical method for testing detection objectives that enables us to select objectives optimal for light-sheet imaging with large-sensor cameras. The improved mesoSPIM achieves high spatial resolution (1.5 µm laterally, 3.3 µm axially) across the entire field of view, magnification up to 20×, and supports sample sizes ranging from sub-mm up to several centimeters while being compatible with multiple clearing techniques. The microscope serves a broad range of applications in neuroscience, developmental biology, pathology, and even physics., (© 2024. The Author(s).)
- Published
- 2024
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7. The Benchtop mesoSPIM: a next-generation open-source light-sheet microscope for large cleared samples.
- Author
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Vladimirov N, Voigt FF, Naert T, Araujo GR, Cai R, Reuss AM, Zhao S, Schmid P, Hildebrand S, Schaettin M, Groos D, Mateos JM, Bethge P, Yamamoto T, Aerne V, Roebroeck A, Ertürk A, Aguzzi A, Ziegler U, Stoeckli E, Baudis L, Lienkamp SS, and Helmchen F
- Abstract
In 2015, we launched the mesoSPIM initiative (www.mesospim.org), an open-source project for making light-sheet microscopy of large cleared tissues more accessible. Meanwhile, the demand for imaging larger samples at higher speed and resolution has increased, requiring major improvements in the capabilities of light-sheet microscopy. Here, we introduce the next-generation mesoSPIM ("Benchtop") with significantly increased field of view, improved resolution, higher throughput, more affordable cost and simpler assembly compared to the original version. We developed a new method for testing objectives, enabling us to select detection objectives optimal for light-sheet imaging with large-sensor sCMOS cameras. The new mesoSPIM achieves high spatial resolution (1.5 μm laterally, 3.3 μm axially) across the entire field of view, a magnification up to 20x, and supports sample sizes ranging from sub-mm up to several centimetres, while being compatible with multiple clearing techniques. The new microscope serves a broad range of applications in neuroscience, developmental biology, and even physics.
- Published
- 2023
- Full Text
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8. Development and Validation of a Deep Learning Method to Predict Cerebral Palsy From Spontaneous Movements in Infants at High Risk.
- Author
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Groos D, Adde L, Aubert S, Boswell L, de Regnier RA, Fjørtoft T, Gaebler-Spira D, Haukeland A, Loennecken M, Msall M, Möinichen UI, Pascal A, Peyton C, Ramampiaro H, Schreiber MD, Silberg IE, Songstad NT, Thomas N, Van den Broeck C, Øberg GK, Ihlen EAF, and Støen R
- Subjects
- Female, Humans, Infant, Male, Movement, Muscle Spasticity, Predictive Value of Tests, Pregnancy, Cerebral Palsy diagnosis, Deep Learning
- Abstract
Importance: Early identification of cerebral palsy (CP) is important for early intervention, yet expert-based assessments do not permit widespread use, and conventional machine learning alternatives lack validity., Objective: To develop and assess the external validity of a novel deep learning-based method to predict CP based on videos of infants' spontaneous movements at 9 to 18 weeks' corrected age., Design, Setting, and Participants: This prognostic study of a deep learning-based method to predict CP at a corrected age of 12 to 89 months involved 557 infants with a high risk of perinatal brain injury who were enrolled in previous studies conducted at 13 hospitals in Belgium, India, Norway, and the US between September 10, 2001, and October 25, 2018. Analysis was performed between February 11, 2020, and September 23, 2021. Included infants had available video recorded during the fidgety movement period from 9 to 18 weeks' corrected age, available classifications of fidgety movements ascertained by the general movement assessment (GMA) tool, and available data on CP status at 12 months' corrected age or older. A total of 418 infants (75.0%) were randomly assigned to the model development (training and internal validation) sample, and 139 (25.0%) were randomly assigned to the external validation sample (1 test set)., Exposure: Video recording of spontaneous movements., Main Outcomes and Measures: The primary outcome was prediction of CP. Deep learning-based prediction of CP was performed automatically from a single video. Secondary outcomes included prediction of associated functional level and CP subtype. Sensitivity, specificity, positive and negative predictive values, and accuracy were assessed., Results: Among 557 infants (310 [55.7%] male), the median (IQR) corrected age was 12 (11-13) weeks at assessment, and 84 infants (15.1%) were diagnosed with CP at a mean (SD) age of 3.4 (1.7) years. Data on race and ethnicity were not reported because previous studies (from which the infant samples were derived) used different study protocols with inconsistent collection of these data. On external validation, the deep learning-based CP prediction method had sensitivity of 71.4% (95% CI, 47.8%-88.7%), specificity of 94.1% (95% CI, 88.2%-97.6%), positive predictive value of 68.2% (95% CI, 45.1%-86.1%), and negative predictive value of 94.9% (95% CI, 89.2%-98.1%). In comparison, the GMA tool had sensitivity of 70.0% (95% CI, 45.7%-88.1%), specificity of 88.7% (95% CI, 81.5%-93.8%), positive predictive value of 51.9% (95% CI, 32.0%-71.3%), and negative predictive value of 94.4% (95% CI, 88.3%-97.9%). The deep learning method achieved higher accuracy than the conventional machine learning method (90.6% [95% CI, 84.5%-94.9%] vs 72.7% [95% CI, 64.5%-79.9%]; P < .001), but no significant improvement in accuracy was observed compared with the GMA tool (85.9%; 95% CI, 78.9%-91.3%; P = .11). The deep learning prediction model had higher sensitivity among infants with nonambulatory CP (100%; 95% CI, 63.1%-100%) vs ambulatory CP (58.3%; 95% CI, 27.7%-84.8%; P = .02) and spastic bilateral CP (92.3%; 95% CI, 64.0%-99.8%) vs spastic unilateral CP (42.9%; 95% CI, 9.9%-81.6%; P < .001)., Conclusions and Relevance: In this prognostic study, a deep learning-based method for predicting CP at 9 to 18 weeks' corrected age had predictive accuracy on external validation, which suggests possible avenues for using deep learning-based software to provide objective early detection of CP in clinical settings.
- Published
- 2022
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9. Synaptic inhibition in the lateral habenula shapes reward anticipation.
- Author
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Lalive AL, Congiu M, Lewis C, Groos D, Clerke JA, Tchenio A, Ge Y, Helmchen F, and Mameli M
- Subjects
- Animals, Calcium, Conditioning, Classical physiology, Mice, Receptors, GABA-A physiology, Reward, gamma-Aminobutyric Acid, Habenula physiology
- Abstract
The lateral habenula (LHb) supports learning processes enabling the prediction of upcoming rewards. While reward-related stimuli decrease the activity of LHb neurons, whether this anchors on synaptic inhibition to guide reward-driven behaviors remains poorly understood. Here, we combine in vivo two-photon calcium imaging with Pavlovian conditioning in mice and report that anticipatory licking emerges along with decreases in cue-evoked calcium signals in individual LHb neurons. In vivo multiunit recordings and pharmacology reveal that the cue-evoked reduction in LHb neuronal firing relies on GABA
A -receptor activation. In parallel, we observe a postsynaptic potentiation of GABAA -receptor-mediated inhibition, but not excitation, onto LHb neurons together with the establishment of anticipatory licking. Finally, strengthening or weakening postsynaptic inhibition with optogenetics and GABAA -receptor manipulations enhances or reduces anticipatory licking, respectively. Hence, synaptic inhibition in the LHb shapes reward anticipation., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)- Published
- 2022
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10. Towards human-level performance on automatic pose estimation of infant spontaneous movements.
- Author
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Groos D, Adde L, Støen R, Ramampiaro H, and Ihlen EAF
- Subjects
- Algorithms, Child, Humans, Infant, Video Recording, Movement, Neural Networks, Computer
- Abstract
Assessment of spontaneous movements can predict the long-term developmental disorders in high-risk infants. In order to develop algorithms for automated prediction of later disorders, highly precise localization of segments and joints by infant pose estimation is required. Four types of convolutional neural networks were trained and evaluated on a novel infant pose dataset, covering the large variation in 1424 videos from a clinical international community. The localization performance of the networks was evaluated as the deviation between the estimated keypoint positions and human expert annotations. The computational efficiency was also assessed to determine the feasibility of the neural networks in clinical practice. The best performing neural network had a similar localization error to the inter-rater spread of human expert annotations, while still operating efficiently. Overall, the results of our study show that pose estimation of infant spontaneous movements has a great potential to support research initiatives on early detection of developmental disorders in children with perinatal brain injuries by quantifying infant movements from video recordings with human-level performance., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2022
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11. Blue-light treatment reduces spontaneous and evoked pain in a human experimental pain model.
- Author
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Reuss AM, Groos D, Scholl R, Schröter M, and Maihöfner C
- Abstract
Introduction: Chronic pain is a frequent severe disease and often associated with anxiety, depression, insomnia, disability, and reduced quality of life. This maladaptive condition is further characterized by sensory loss, hyperalgesia, and allodynia. Blue light has been hypothesized to modulate sensory neurons and thereby influence nociception., Objectives: Here, we compared the effects of blue light vs red light and thermal control on pain sensation in a human experimental pain model., Methods: Pain, hyperalgesia, and allodynia were induced in 30 healthy volunteers through high-density transcutaneous electrical stimulation. Subsequently, blue light, red light, or thermal control treatment was applied in a cross-over design. The nonvisual effects of the respective light treatments were examined using a well-established quantitative sensory testing protocol. Somatosensory parameters as well as pain intensity and quality were scored., Results: Blue light substantially reduced spontaneous pain as assessed by numeric rating scale pain scoring. Similarly, pain quality was significantly altered as assessed by the German counterpart of the McGill Pain Questionnaire. Furthermore, blue light showed antihyperalgesic, antiallodynic, and antihypesthesic effects in contrast to red light or thermal control treatment., Conclusion: Blue-light phototherapy ameliorates pain intensity and quality in a human experimental pain model and reveals antihyperalgesic, antiallodynic, and antihypesthesic effects. Therefore, blue-light phototherapy may be a novel approach to treat pain in multiple conditions., Competing Interests: A. M. Reuss, D. Groos, M. Schröter, and R. Scholl declare no competing financial or nonfinancial conflict of interest. In the past 3 years, C. Maihöfner has worked as a consultant and speaker for the following companies: Allergan, Bionorica, Biotest, Grünenthal, GSK, Lilly, Novartis, and Daiichi Sankyo. The present work was performed in fulfillment of the requirements for obtaining the degree “Dr. med.” by Anna Maria Reuss.Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The International Association for the Study of Pain.)
- Published
- 2021
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12. Performance Analysis in Ski Jumping with a Differential Global Navigation Satellite System and Video-Based Pose Estimation.
- Author
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Elfmark O, Ettema G, Groos D, Ihlen EAF, Velta R, Haugen P, Braaten S, and Gilgien M
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- Athletes, Biomechanical Phenomena, Humans, Kinetics, Skiing
- Abstract
This study investigated the explanatory power of a sensor fusion of two complementary methods to explain performance and its underlying mechanisms in ski jumping. A differential Global Navigation Satellite System (dGNSS) and a markerless video-based pose estimation system (PosEst) were used to measure the kinematics and kinetics from the start of the in-run to the landing. The study had two aims; firstly, the agreement between the two methods was assessed using 16 jumps by athletes of national level from 5 m before the take-off to 20 m after, where the methods had spatial overlap. The comparison revealed a good agreement from 5 m after the take-off, within the uncertainty of the dGNSS (±0.05m). The second part of the study served as a proof of concept of the sensor fusion application, by showcasing the type of performance analysis the systems allows. Two ski jumps by the same ski jumper, with comparable external conditions, were chosen for the case study. The dGNSS was used to analyse the in-run and flight phase, while the PosEst system was used to analyse the take-off and the early flight phase. The proof-of-concept study showed that the methods are suitable to track the kinematic and kinetic characteristics that determine performance in ski jumping and their usability in both research and practice.
- Published
- 2021
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13. The Acidic Brain-Glycolytic Switch in the Microenvironment of Malignant Glioma.
- Author
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Reuss AM, Groos D, Buchfelder M, and Savaskan N
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- Animals, Brain Chemistry, Brain Neoplasms physiopathology, Carbonic Anhydrases, Glioma physiopathology, Humans, Hydrogen-Ion Concentration, Neovascularization, Pathologic, Brain metabolism, Brain Neoplasms metabolism, Glioma metabolism, Glycolysis, Lactic Acid metabolism, Tumor Microenvironment
- Abstract
Malignant glioma represents a fatal disease with a poor prognosis and development of resistance mechanisms against conventional therapeutic approaches. The distinct tumor zones of this heterogeneous neoplasm develop their own microenvironment, in which subpopulations of cancer cells communicate. Adaptation to hypoxia in the center of the expanding tumor mass leads to the glycolytic and angiogenic switch, accompanied by upregulation of different glycolytic enzymes, transporters, and other metabolites. These processes render the tumor microenvironment more acidic, remodel the extracellular matrix, and create energy gradients for the metabolic communication between different cancer cells in distinct tumor zones. Escape mechanisms from hypoxia-induced cell death and energy deprivation are the result. The functional consequences are more aggressive and malignant behavior with enhanced proliferation and survival, migration and invasiveness, and the induction of angiogenesis. In this review, we go from the biochemical principles of aerobic and anaerobic glycolysis over the glycolytic switch, regulated by the key transcription factor hypoxia-inducible factor (HIF)-1α, to other important metabolic players like the monocarboxylate transporters (MCTs)1 and 4. We discuss the metabolic symbiosis model via lactate shuttling in the acidic tumor microenvironment and highlight the functional consequences of the glycolytic switch on glioma malignancy. Furthermore, we illustrate regulation by micro ribonucleic acids (miRNAs) and the connection between isocitrate dehydrogenase (IDH) mutation status and glycolytic metabolism. Finally, we give an outlook about the diagnostic and therapeutic implications of the glycolytic switch and the relation to tumor immunity in malignant glioma.
- Published
- 2021
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14. MCT4 Promotes Tumor Malignancy in F98 Glioma Cells.
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Reuss AM, Groos D, Ghoochani A, Buchfelder M, and Savaskan N
- Abstract
Monocarboxylate transporter 4 (MCT4, SLC16A3 ) is elevated under hypoxic conditions in many malignant tumors including gliomas. Moreover, MCT4 expression is associated with shorter overall survival. However, the functional consequences of MCT4 expression on the distinct hallmarks of cancer have not yet been explored at the cellular level. Here, we investigated the impact of MCT4 overexpression on proliferation, survival, cell death, migration, invasion, and angiogenesis in F98 glioma cells. Stable F98 glioma cell lines with MCT4 overexpression, normal expression, and knockdown were generated. Distinct hallmarks of cancer were examined using in silico analysis, various in vitro cell culture assays, and ex vivo organotypic rat brain slice culture model. Consistent with its function as lactate and proton exporter, MCT4 expression levels correlated inversely with extracellular pH and proportionally with extracellular lactate concentrations. Our results further indicate that MCT4 promotes proliferation and survival by altered cell cycle regulation and cell death mechanisms. Moreover, MCT4 overexpression enhances cell migration and invasiveness via reorganization of the actin cytoskeleton. Finally, MCT4 inhibition mitigates the induction of angiogenesis, suggesting that MCT4 also plays a crucial role in tumor-related angiogenesis. In summary, our data highlight MCT4 /SLC16A3 as a key gene for distinct hallmarks of tumor malignancy in glioma cells., Competing Interests: The authors declare that they have no conflicts of interest regarding the publication of this paper., (Copyright © 2021 Anna Maria Reuss et al.)
- Published
- 2021
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15. In-Motion-App for remote General Movement Assessment: a multi-site observational study.
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Adde L, Brown A, van den Broeck C, DeCoen K, Eriksen BH, Fjørtoft T, Groos D, Ihlen EAF, Osland S, Pascal A, Paulsen H, Skog OM, Sivertsen W, and Støen R
- Subjects
- Belgium, Child, Humans, Infant, Movement, Norway, Parents, Smartphone, Mobile Applications
- Abstract
Objectives: To determine whether videos taken by parents of their infants' spontaneous movements were in accordance with required standards in the In-Motion-App, and whether the videos could be remotely scored by a trained General Movement Assessment (GMA) observer. Additionally, to assess the feasibility of using home-based video recordings for automated tracking of spontaneous movements, and to examine parents' perceptions and experiences of taking videos in their homes., Design: The study was a multi-centre prospective observational study., Setting: Parents/families of high-risk infants in tertiary care follow-up programmes in Norway, Denmark and Belgium., Methods: Parents/families were asked to video record their baby in accordance with the In-Motion standards which were based on published GMA criteria and criteria covering lighting and stability of smartphone. Videos were evaluated as GMA 'scorable' or 'non-scorable' based on predefined criteria. The accuracy of a 7-point body tracker software was compared with manually annotated body key points. Parents were surveyed about the In-Motion-App information and clarity., Participants: The sample comprised 86 parents/families of high-risk infants., Results: The 86 parent/families returned 130 videos, and 121 (96%) of them were in accordance with the requirements for GMA assessment. The 7-point body tracker software detected more than 80% of body key point positions correctly. Most families found the instructions for filming their baby easy to follow, and more than 90% reported that they did not become more worried about their child's development through using the instructions., Conclusions: This study reveals that a short instructional video enabled parents to video record their infant's spontaneous movements in compliance with the standards required for remote GMA. Further, an accurate automated body point software detecting infant body landmarks in smartphone videos will facilitate clinical and research use soon. Home-based video recordings could be performed without worrying parents about their child's development., Trials Registration Number: NCT03409978., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2021
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16. A dopaminergic mechanism of antipsychotic drug efficacy, failure, and failure reversal: the role of the dopamine transporter.
- Author
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Amato D, Canneva F, Cumming P, Maschauer S, Groos D, Dahlmanns JK, Grömer TW, Chiofalo L, Dahlmanns M, Zheng F, Kornhuber J, Prante O, Alzheimer C, von Hörsten S, and Müller CP
- Subjects
- Animals, Dopamine therapeutic use, Dopamine Plasma Membrane Transport Proteins, Rats, Receptors, Dopamine D2 metabolism, Antipsychotic Agents pharmacology, Antipsychotic Agents therapeutic use, Schizophrenia drug therapy
- Abstract
Antipsychotic drugs are effective interventions in schizophrenia. However, the efficacy of these agents often decreases over time, which leads to treatment failure and symptom recurrence. We report that antipsychotic efficacy in rat models declines in concert with extracellular striatal dopamine levels rather than insufficient dopamine D2 receptor occupancy. Antipsychotic efficacy was associated with a suppression of dopamine transporter activity, which was reversed during failure. Antipsychotic failure coincided with reduced dopamine neuron firing, which was not observed during antipsychotic efficacy. Synaptic field responses in dopamine target areas declined during antipsychotic efficacy and showed potentiation during failure. Antipsychotics blocked synaptic vesicle release during efficacy but enhanced this release during failure. We found that the pharmacological inhibition of the dopamine transporter rescued antipsychotic drug treatment outcomes, supporting the hypothesis that the dopamine transporter is a main target of antipsychotic drugs and predicting that dopamine transporter blockers may be an adjunct treatment to reverse antipsychotic treatment failure.
- Published
- 2020
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17. Chronic antipsychotic treatment targets GIRK current suppression, loss of long-term synaptic depression and behavioural sensitization in a mouse model of amphetamine psychosis.
- Author
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Groos D, Zheng F, Rauh M, Quinger B, Kornhuber J, Müller CP, and Alzheimer C
- Abstract
Background:: Antipsychotic drugs (APDs) are the mainstay of the pharmacological treatment of psychotic disorders like schizophrenia. While the clinical efficacy of APDs has long since been established, the neurobiological mechanisms underlying their therapeutic benefits are still not well understood., Methods:: Here, we used an escalating amphetamine regimen to induce a psychosis-like state in mice. To achieve clinically relevant drug concentrations in amphetamine-pretreated mice, the typical APD haloperidol or the atypical APD olanzapine were chronically administered via subcutaneously implanted osmotic mini-pumps., Results:: Demonstrating their therapeutic efficacy, both drugs dampened amphetamine-induced hyperlocomotion and restored normal behaviour in the light-induced activity test. Whole-cell recordings from dopaminergic neurons of the ventral tegmental area (VTA) in ex vivo brain slices revealed two pronounced aberrations associated with the psychosis-like state: Strongly enhanced spontaneous firing and a substantial loss of G protein-gated inwardly rectifying potassium (GIRK) current upon activation of GABA
B receptors with baclofen. Chronic haloperidol and olanzapine restored normal firing and partially rescued the GIRK current response to baclofen. In ex vivo slices containing the nucleus accumbens, which receives a dopaminergic projection from the VTA, abrogation of long-term synaptic depression (LTD) and enhanced excitatory drive onto medium spiny neurons were identified as synaptic consequences of amphetamine-induced psychosis. Again, both alterations proved amenable to chronic APD treatment., Conclusion:: Our data provide evidence for aberrant neuronal function and plasticity in the mesolimbic dopamine system during an induced psychotic state and identify these alterations as targets of chronic APD treatment.- Published
- 2018
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18. Behavioral Strategy Determines Frontal or Posterior Location of Short-Term Memory in Neocortex.
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Gilad A, Gallero-Salas Y, Groos D, and Helmchen F
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- Animals, Male, Mice, Mice, Transgenic, Optogenetics methods, Random Allocation, Discrimination Learning physiology, Memory, Short-Term physiology, Neocortex chemistry, Neocortex physiology
- Abstract
The location of short-term memory in mammalian neocortex remains elusive. Here we show that distinct neocortical areas maintain short-term memory depending on behavioral strategy. Using wide-field and single-cell calcium imaging, we measured layer 2/3 neuronal activity in mice performing a whisker-based texture discrimination task with delayed response. Mice either deployed an active strategy-engaging their body toward the approaching texture-or passively awaited the touch. Independent of strategy, whisker-related posterior areas encoded choice early after touch. During the delay, in contrast, persistent cortical activity was located medio-frontally in active trials but in a lateral posterior area in passive trials. Perturbing these areas impaired performance for the associated strategy and also provoked strategy switches. Frontally maintained information related to future action, whereas activity in the posterior cortex reflected past stimulus identity. Thus, depending on behavioral strategy, cortical activity is routed differentially to hold information either frontally or posteriorly before converging to similar action., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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19. Neuropharmacology of light-induced locomotor activation.
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Amato D, Pum ME, Groos D, Lauber AC, Huston JP, Carey RJ, de Souza Silva MA, and Müller CP
- Subjects
- Animals, Dose-Response Relationship, Drug, Haloperidol pharmacology, Indoles pharmacology, Ketamine pharmacology, Male, Naphthyridines pharmacology, Phencyclidine pharmacology, Photic Stimulation, Piperazines pharmacology, Piperidines pharmacology, Pyridines pharmacology, Quinpirole pharmacology, Rats, Wistar, Receptors, N-Methyl-D-Aspartate antagonists & inhibitors, Receptors, N-Methyl-D-Aspartate metabolism, Ritanserin pharmacology, Dopamine Agents pharmacology, Excitatory Amino Acid Agents pharmacology, Light, Motor Activity drug effects, Motor Activity radiation effects, Serotonin Antagonists pharmacology
- Abstract
Presentation of non-aversive light stimuli for several seconds was found to reliably induce locomotor activation and exploratory-like activity. Light-induced locomotor activity (LIA) can be considered a convenient simple model to study sensory-motor activation. LIA was previously shown to coincide with serotonergic and dopaminergic activation in specific cortical areas in freely moving and anesthetized animals. In the present study we explore the neuropharmacology of LIA using a receptor antagonist/agonist approach in rats. The non-selective 5-HT2-receptor antagonist ritanserin (1.5-6 mg/kg, i.p.) dose-dependently reduced LIA. Selective antagonism of either the 5-HT2A-receptor by MDL 11,939 (0.1-0.4 mg/kg, i.p.), or the 5-HT2C-receptor by SDZ SER 082 (0.125-0.5 mg/kg, i.p.), alone or in combination, had no significant influence on LIA. Also the selective 5-HT1A-receptor antagonist, WAY 100635 (0.4 mg/kg, i.p.) did not affect LIA. Neither did the preferential dopamine D2-receptor antagonist, haloperidol (0.025-0.1 mg/kg, i.p.) nor the D2/D3-receptor agonist, quinpirole (0.025-0.5 mg/kg, i.p.) affect the expression of LIA. However, blocking the glutamatergic NMDA-receptor with phencyclidine (PCP, 1.5-6 mg/kg, i.p.) dose-dependently reduced LIA. This effect was also observed with ketamine (10 mg/kg, i.p.). These findings suggest that serotonin and dopamine receptors abundantly expressed in the cortex do not mediate light-stimulus triggered locomotor activity. PCP and ketamine effects, however, suggest an important role of NMDA receptors in LIA., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2015
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20. Multilevel spinal fusion in the aged: not a panacea.
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Röllinghoff M, Zarghooni K, Groos D, Siewe J, Eysel P, and Sobottke R
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- Aged, Aged, 80 and over, Female, Follow-Up Studies, Humans, Male, Middle Aged, Retrospective Studies, Spinal Fusion adverse effects, Treatment Outcome, Low Back Pain surgery, Lumbar Vertebrae surgery, Spinal Fusion methods, Spondylosis surgery
- Abstract
The authors conducted a retrospective study on the outcome after multilevel spine fusion in elderly patients. Seventy-two out of 80 patients were available after a mean follow-up period of 29.4 months. There were 47 females and 25 males. Their mean age at operation was 68.7 years, which means that many complaints may have been due to an underlying osteoporosis, unresponsive to surgical treatment, and exposing to loosening of the implants. The outcome was indeed rather poor: only 50% of the patients were satisfied. VAS and ODI improved slightly, but not significantly. Implant loosening was the main complication: it occurred in 35 patients, but necessitated re-operation in only 8. Adjacent segment degeneration (ASD) occurred in 26 patients, and necessitated re-operation in 17. This study should be a warning against an interventionist attitude in older patients with so-called spondylosis, where osteoporosis should be excluded and, if present, should be treated as a first step.
- Published
- 2011
21. Mid-range outcomes in 64 consecutive cases of multilevel fusion for degenerative diseases of the lumbar spine.
- Author
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Röllinghoff M, Schlüter-Brust K, Groos D, Sobottke R, Michael JW, Eysel P, and Delank KS
- Abstract
In the treatment of multilevel degenerative disorders of the lumbar spine, spondylodesis plays a controversial role. Most patients can be treated conservatively with success. Multilevel lumbar fusion with instrumentation is associated with severe complications like failed back surgery syndrome, implant failure, and adjacent segment disease (ASD). This retrospective study examines the records of 70 elderly patients with degenerative changes or instability of the lumbar spine treated between 2002 and 2007 with spondylodesis of more than two segments. Sixty-four patients were included; 5 patients had died and one patient was lost to follow-up. We evaluated complications, clinical/radiological outcomes, and success of fusion. Flexion-extension and standing X-rays in two planes, MRI, and/or CT scans were obtained pre-operatively. Patients were assessed clinically using the Oswestry disability index (ODI) and a Visual Analogue Scale (VAS). Surgery performed was dorsolateral fusion (46.9%) or dorsal fusion with anterior lumbar interbody fusion (ALIF; 53.1%). Additional decompression was carried out in 37.5% of patients. Mean follow-up was 29.4±5.4 months. Average patient age was 64.7±4.3 years. Clinical outcomes were not satisfactory for all patients. VAS scores improved from 8.6±1.3 to 5.6±3.0 pre- to post-operatively, without statistical significance. ODI was also not significantly improved (56.1±22.3 pre- and 45.1±26.4 post-operatively). Successful fusion, defined as adequate bone mass with trabeculation at the facets and transverse processes or in the intervertebral segments, did not correlate with good clinical outcomes. Thirty-five of 64 patients (54%) showed signs of pedicle screw loosening, especially of the screws at S1. However, only 7 of these 35 (20%) complained of corresponding back pain. Revision surgery was required in 24 of 64 patients (38%). Of these, indications were adjacent segment disease (16 cases), pedicle screw loosening (7 cases), and infection (one case). At follow-up of 29.4 months, patients with radiographic ASD had worse ODI scores than patients without (54.7 vs. 36.6; P<0.001). Multilevel fusion for degenerative disease still has a high rate of complications, up to 50%. The problem of adjacent segment disease after fusion surgery has not yet been solved. This study underscores the need for strict indication guidelines to perform lumbar spine fusion of more than two levels.
- Published
- 2010
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