Article
Endocrinology & Metabolism
Karl Schoknecht, Majed Kikhia, Coline L. Lemale, Agustin Liotta, Svetlana Lublinsky, Susanne Mueller, Philipp Boehm-Sturm, Alon Friedman, Jens P. Dreier
Summary: The study found that ketamine may help counteract the early progression of ischemic injury, reducing the onset of SDs, lesion volume, and neuronal injury.
JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM
(2021)
Article
Neurosciences
Azat Gainutdinov, Elvira Juzekaeva, Marat Mukhtarov, Roustem Khazipov
Summary: Anoxic spreading depolarization (aSD) is a characteristic of cerebral cortex ischemic injury. In immature neurons, the behavior during aSD is complex, with initial moderate depolarization, transient repolarization, and terminal depolarization. Neurons mildly depolarized during aSD can still fire action potentials, and most immature neurons regain their functions during post-aSD transient repolarization. The developmental changes in neuronal function during aSD may contribute to lower susceptibility to ischemia in immature neurons.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2023)
Review
Medicine, Research & Experimental
Christine Nash, Keren Powell, Daniel G. Lynch, Jed A. Hartings, Chunyan Li
Summary: This review summarizes nonpharmacological techniques for modulating cortical spreading depolarization (CSD), presents their mechanisms of action, and provides insight into future directions. Both pharmacologic and nonpharmacologic interventions can mitigate the pathological impact of CSDs via shared molecular mechanisms, and nonpharmacologic interventions can also target unique mechanisms, which may have broader effects.
Article
Cell Biology
Bin Lu, Sen-Sen Lou, Ruo-Shui Xu, De-Lun Kong, Rong-Jie Wu, Jing Zhang, Ling Zhuang, Xue-Mei Wu, Jun-Yan He, Zhi-Ying Wu, Zhi-Qi Xiong
Summary: Paroxysmal kinesigenic dyskinesia (PKD) is characterized by involuntary movements triggered by sudden changes in movement, with Proline-rich transmembrane protein 2 (PRRT2) identified as a major causative gene. Research shows that PRRT2 deficiency enhances cerebellar spreading depolarization (SD), which is closely linked to dyskinetic movements, suggesting a potential target for treating related disorders.
Article
Critical Care Medicine
Maria Sueiras, Vanessa Thonon, Estevo Santamarina, Angela Sanchez-Guerrero, Marilyn Riveiro, Maria-Antonia Poca, Manuel Quintana, Dario Gandara, Juan Sahuquillo
Summary: This study evaluated the relationship between spreading depolarizations (SDs) and epilepsy, as well as clinical outcomes. Results indicated a significant correlation between SDs, EEG activity, and disability severity in patients. While the presence of SDs may lead to worse long-term outcomes, there was not a strong association with subsequent epilepsy.
NEUROCRITICAL CARE
(2021)
Article
Neurosciences
Fatima Gimeno-Ferrer, Annett Eitner, Reinhard Bauer, Alfred Lehmenkuehler, Marie-Luise Edenhofer, Michaela Kress, Hans-Georg Schaible, Frank Richter
Summary: CGRP release plays a major role in migraine pain by activating the trigeminal pain pathways. This study explores additional effects of CGRP on cortical circuits and investigates its impact on cortical excitability, cortical spreading depolarization (CSD), blood-brain-barrier (BBB), and microglial morphology.
EXPERIMENTAL NEUROLOGY
(2022)
Article
Critical Care Medicine
Sangwoo Han, Mayra Isabel Contreras, Afsheen Bazrafkan, Masih Rafi, Shirin M. Dara, Ani Orujyan, Anais Panossian, Christian Crouzet, Beth Lopour, Bernard Choi, Robert H. Wilson, Yama Akbari
Summary: This study explored the role of anoxic spreading depolarizations (SD) in cerebral hemodynamics and metabolism, peripheral blood pressure, and the relationship between these variables in rats. The results showed decoupling of peripheral blood pressure from cerebral blood flow and metabolism during anoxic SD, possible modification of cerebrovascular resistance by anoxic SD, and a correlation between shorter time differences between anoxic SDs and better neurological outcomes.
NEUROCRITICAL CARE
(2022)
Article
Critical Care Medicine
Akos Menyhart, Daniel Peter Varga, Orsolya M. Toth, Peter Makra, Ferenc Bari, Eszter Farkas
Summary: The study investigates the interplay between impaired cerebrovascular autoregulation, SD occurrence, and the evolution of the SD-coupled CBF response in acute brain injury, suggesting dysfunction of autoregulation poses a risk of SD occurrence and damages neurovascular coupling.
NEUROCRITICAL CARE
(2022)
Article
Endocrinology & Metabolism
Eun-Jeung Kang, Ofer Prager, Svetlana Lublinsky, Ana Oliveira-Ferreira, Clemens Reiffurth, Sebastian Major, Dominik N. Mueller, Alon Friedman, Jens P. Dreier
Summary: Spreading depolarization (SD) is a phenomenon that occurs in various clinical conditions, such as migraine, delayed ischemia, and stroke. It involves disturbances in ion homeostasis, particularly sodium homeostasis, in the brain. SD can cause changes in resistance vessels, leading to either increased blood flow in healthy tissue or decreased blood flow in at-risk tissue. Research suggests a possible link between SD, vascular dysfunction, and salt-sensitive hypertension through genetic dysfunction of the α(2)-isoform of Na+/K+-ATPase. Genetic models of salt-sensitive hypertension, such as stroke-prone spontaneously hypertensive rats (SHRsp), also show altered SD thresholds and hemodynamic responses. These findings have implications for understanding migraine with aura and stroke.
JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM
(2023)
Article
Neurosciences
Craig Kelley, Adam J. H. Newton, Sabina Hrabetova, Robert A. McDougal, William W. Lytton
Summary: The study developed a multiscale computational model of spreading depolarization (SD) in brain slices and made testable predictions regarding the characteristics of SD under different conditions, such as the inhibitory effect of enlarging extracellular space volume on SD and the faster propagation of SD in areas with higher neuronal density.
Article
Cell Biology
Kinsey A. Barhorst, Yara Alfawares, Jennifer L. McGuire, Steve C. Danzer, Jed A. Hartings, Laura B. Ngwenya
Summary: This study reveals that spreading depolarizations (SDs) in healthy brain tissue can lead to changes in glutamate receptor subunit expression, potentially playing a role in brain plasticity.
CELLULAR AND MOLECULAR NEUROBIOLOGY
(2022)
Article
Clinical Neurology
Marina Vitale, Angelita Tottene, Maral Zarin Zadeh, K. C. Brennan, Daniela Pietrobon
Summary: This study investigated the mechanisms of cortical spreading depression (CSD) initiation by applying high KCl puffs in mouse cerebral cortex slices. The results showed that the initiation of CSD requires the combined action of NMDARs and Ca-V channels, and is not determined by extracellular K+ concentration or neuronal depolarization levels.
JOURNAL OF HEADACHE AND PAIN
(2023)
Article
Nanoscience & Nanotechnology
Di Wu, Yong Hou, Zhiqin Chu, Qiang Wei, Wei Hong, Yuan Lin
Summary: Cells rely on receptor-ligand binding to connect and communicate with the external environment. Understanding the interaction between receptors and ligands is crucial for comprehending cellular biology. Recent evidence suggests that the mobility of ligands at the cell-ECM interface affects cell adhesion and spreading, but the underlying mechanism is unclear. This modeling investigation reveals a biphasic relationship between adhesion and ligand diffusivity, with peak spreading observed at intermediate ligand mobility. The aggregation of ligands and the kinetics of bond association/dissociation play a role in determining this peak position.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Biochemistry & Molecular Biology
Mariia P. Smirnova, Tatiana M. Medvedeva, Irina Pavlova, Lyudmila V. Vinogradova
Summary: The study demonstrates that the amygdala has different susceptibilities to SD, with the basolateral (BLA) region more prone to SD compared to the centromedial (CMA) region. The spatiotemporal features of SD triggered in the amygdala show diverse propagation patterns to the cortex.
Article
Chemistry, Multidisciplinary
Shengnan Xu, Chen Si, Yang Li, Bing-Lin Gu, Wenhui Duan
Summary: The study reveals the existence of a satellite Gamma valley in monolayer MoS2, providing an additional relaxation path for holes and ensuring ultrafast valley depolarization. It may have significant implications for controlling valley depolarization in multivalley materials.
Article
Mathematics, Applied
Paul Carter, Edgar Knobloch, Martin Wechselberger
Article
Mathematics, Applied
John Mitry, Martin Wechselberger
SIAM JOURNAL ON APPLIED DYNAMICAL SYSTEMS
(2017)
Article
Biochemical Research Methods
Yina Wei, Giri P. Krishnan, Maxim Komarov, Maxim Bazhenov
PLOS COMPUTATIONAL BIOLOGY
(2018)
Article
Mathematics, Applied
Samuel Jelbart, Martin Wechselberger
Article
Mathematics, Applied
Ian Lizarraga, Robert Marangell, Martin Wechselberger
JOURNAL OF NONLINEAR SCIENCE
(2020)
Article
Mathematics
Samuel Jelbart, Kristian Uldall Kristiansen, Martin Wechselberger
Summary: We study the transition of smooth systems to piecewise-smooth systems with a boundary-focus bifurcation as epsilon -> 0, and identify different bifurcation structures. We uncover the evolution characteristics of cycles associated with BF bifurcations in the smooth system, and prove the existence of a family of stable limit cycles.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2021)
Article
Mathematics, Applied
S. Jelbart, K. U. Kristiansen, P. Szmolyan, M. Wechselberger
Summary: This paper investigates two prototypical singularly perturbed oscillators with exponential nonlinearities, normalizing both systems to a piecewise smooth system in the limit is an element of -> 0, showing exponential convergence due to the nonlinearities studied. By extending spatial dimensions, degeneracies caused by exponentially small terms are tackled for the second model system, with (unique) limit cycles proven to exist for both systems by perturbing away from singular cycles with desirable hyperbolicity properties.
JOURNAL OF DYNAMICS AND DIFFERENTIAL EQUATIONS
(2022)
Article
Mathematics, Applied
S. Jelbart, K. U. Kristiansen, M. Wechselberger
Summary: This work completes a classification of codimension-1 singularly perturbed boundary equilibria bifurcation (BEB) in the plane, utilizing tools from PWS theory, geometric singular perturbation theory, and the method of geometric desingularization known as blow-up. Local normal forms for generating all 12 singularly perturbed BEBs are derived, and the unfolding in each case is described. Detailed quantitative results on various bifurcations involved in the unfoldings and classification are presented, including saddle-node, Andronov-Hopf, homoclinic, and codimension-2 Bogdanov-Takens bifurcations.
Article
Mathematics, Applied
Ian Lizarraga, Bob Rink, Martin Wechselberger
Summary: The novel method presented in this study computes slow manifolds and fast fibre bundles in geometric singular perturbation problems with high degrees of accuracy, making it suitable for systems with multiple timescales. This top-down approach highlights the emergence of hidden timescales and can uncover surprising multiple timescale structures. It has been successfully applied to various reaction network problems.
Article
Mathematics, Applied
Yifei Li, Peter van Heijster, Matthew J. Simpson, Martin Wechselberger
Summary: Reaction-diffusion equations (RDEs) are derived from lattice-based discrete models, with recent developments allowing for negative diffusion terms. Numerical simulations support shock-fronted travelling waves in RDEs with Allee effects. By embedding RDEs in a larger class of PDEs, the existence of shock-fronted travelling waves has been proven, with different embeddings leading to waves with varying properties.
PHYSICA D-NONLINEAR PHENOMENA
(2021)
Article
Astronomy & Astrophysics
Eric W. Hester, Geoffrey M. Vasil, Martin Wechselberger
Summary: This study investigates shocks in a thin isothermal black hole accretion flow and finds that the inner shock is always unstable while the outer shock is always stable. The growth/decay rates of perturbations depend on an effective potential and the incoming-outgoing flow difference at the shock location. A prescription of accretion regimes in terms of angular momentum and black hole radius is provided, with unstable outer shocks being implied in much of the parameter space when accounting for viscous angular momentum dissipation.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Mathematics, Applied
Samuel Jelbart, Nathan Pages, Vivien Kirk, James Sneyd, Martin Wechselberger
Summary: This article discusses ordinary differential equations (ODEs) used to model phenomena in chemistry, biology, and neuroscience, and presents a heuristic procedure for identifying small parameters in these ODE models. The procedure is applied to a model of intracellular calcium dynamics characterized by switching and multiple time-scale dynamics. Using geometric singular perturbation theory, the existence and uniqueness of stable relaxation oscillations with three distinct time scales are proven, and an estimate for the period of the oscillations is provided.
SIAM JOURNAL ON APPLIED DYNAMICAL SYSTEMS
(2022)
Article
Mathematics, Applied
Daniele Avitabile, Mathieu Desroches, Romain Veltz, Martin Wechselberger
SIAM JOURNAL ON MATHEMATICAL ANALYSIS
(2020)
Article
Mathematics, Applied
Kristen E. Harley, Peter van Heijster, Robert Marangell, Graeme J. Pettet, Timothy Roberts, Martin Wechselberger
SIAM JOURNAL ON APPLIED MATHEMATICS
(2020)
Article
Mathematics, Applied
Ian Lizarraga, Martin Wechselberger
SIAM JOURNAL ON APPLIED DYNAMICAL SYSTEMS
(2020)