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Carbonero D, Noueihed J, Kramer MA, White JA. Non-Negative Matrix Factorization for Analyzing State Dependent Neuronal Network Dynamics in Calcium Recordings. bioRxiv 2024:2023.10.11.561797. [PMID: 37905071 PMCID: PMC10614735 DOI: 10.1101/2023.10.11.561797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Calcium imaging allows recording from hundreds of neurons in vivo with the ability to resolve single cell activity. Evaluating and analyzing neuronal responses, while also considering all dimensions of the data set to make specific conclusions, is extremely difficult. Often, descriptive statistics are used to analyze these forms of data. These analyses, however, remove variance by averaging the responses of single neurons across recording sessions, or across combinations of neurons, to create single quantitative metrics, losing the temporal dynamics of neuronal activity, and their responses relative to each other. Dimensionally Reduction (DR) methods serve as a good foundation for these analyses because they reduce the dimensions of the data into components, while still maintaining the variance. Non-negative Matrix Factorization (NMF) is an especially promising DR analysis method for analyzing activity recorded in calcium imaging because of its mathematical constraints, which include positivity and linearity. We adapt NMF for our analyses and compare its performance to alternative dimensionality reduction methods on both artificial and in vivo data. We find that NMF is well-suited for analyzing calcium imaging recordings, accurately capturing the underlying dynamics of the data, and outperforming alternative methods in common use.
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Subramaniam S, Akay M, Anastasio MA, Bailey V, Boas D, Bonato P, Chilkoti A, Cochran JR, Colvin V, Desai TA, Duncan JS, Epstein FH, Fraley S, Giachelli C, Grande-Allen KJ, Green J, Guo XE, Hilton IB, Humphrey JD, Johnson CR, Karniadakis G, King MR, Kirsch RF, Kumar S, Laurencin CT, Li S, Lieber RL, Lovell N, Mali P, Margulies SS, Meaney DF, Ogle B, Palsson B, A. Peppas N, Perreault EJ, Rabbitt R, Setton LA, Shea LD, Shroff SG, Shung K, Tolias AS, van der Meulen MC, Varghese S, Vunjak-Novakovic G, White JA, Winslow R, Zhang J, Zhang K, Zukoski C, Miller MI. Grand Challenges at the Interface of Engineering and Medicine. IEEE Open J Eng Med Biol 2024; 5:1-13. [PMID: 38415197 PMCID: PMC10896418 DOI: 10.1109/ojemb.2024.3351717] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 08/30/2023] [Accepted: 09/03/2023] [Indexed: 02/29/2024] Open
Abstract
Over the past two decades Biomedical Engineering has emerged as a major discipline that bridges societal needs of human health care with the development of novel technologies. Every medical institution is now equipped at varying degrees of sophistication with the ability to monitor human health in both non-invasive and invasive modes. The multiple scales at which human physiology can be interrogated provide a profound perspective on health and disease. We are at the nexus of creating "avatars" (herein defined as an extension of "digital twins") of human patho/physiology to serve as paradigms for interrogation and potential intervention. Motivated by the emergence of these new capabilities, the IEEE Engineering in Medicine and Biology Society, the Departments of Biomedical Engineering at Johns Hopkins University and Bioengineering at University of California at San Diego sponsored an interdisciplinary workshop to define the grand challenges that face biomedical engineering and the mechanisms to address these challenges. The Workshop identified five grand challenges with cross-cutting themes and provided a roadmap for new technologies, identified new training needs, and defined the types of interdisciplinary teams needed for addressing these challenges. The themes presented in this paper include: 1) accumedicine through creation of avatars of cells, tissues, organs and whole human; 2) development of smart and responsive devices for human function augmentation; 3) exocortical technologies to understand brain function and treat neuropathologies; 4) the development of approaches to harness the human immune system for health and wellness; and 5) new strategies to engineer genomes and cells.
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Affiliation(s)
- Shankar Subramaniam
- Joan and Irwin Jacobs Endowed Chair in Bioengineering and Systems Biology, Distinguished Professor of Bioengineering, Computer Science & Engineering, Cellular & Molecular Medicine, and NanoengineeringUniversity of California San DiegoLa JollaCA92093-0412USA
| | - Metin Akay
- Department of Physical Medicine and Rehabilitation, Harvard Medical SchoolSpaulding Rehabilitation HospitalCharlestownMA02129USA
- Founding Chair of the Biomedical Engineering Department and John S. Dunn Professor of Biomedical EngineeringUniversity of HoustonHoustonTX77204-5060USA
- Donald Biggar Willett Professor in Engineering and Head of the Department of BioengineeringUrbanaIL61801USA
- Senior PartnerArtis VenturesSan FranciscoCA94111USA
| | - Mark A. Anastasio
- Department of Physical Medicine and Rehabilitation, Harvard Medical SchoolSpaulding Rehabilitation HospitalCharlestownMA02129USA
| | - Vasudev Bailey
- Department of Physical Medicine and Rehabilitation, Harvard Medical SchoolSpaulding Rehabilitation HospitalCharlestownMA02129USA
| | - David Boas
- Professor of Biomedical Engineering and Director of Neurophotonics CenterBoston University College of EngineeringBostonMA02215USA
| | - Paolo Bonato
- Department of Physical Medicine and Rehabilitation, Harvard Medical SchoolSpaulding Rehabilitation HospitalCharlestownMA02129USA
| | - Ashutosh Chilkoti
- Alan L. Kaganov Professor of Biomedical Engineering and Chair of the Department of Biomedical EngineeringDuke UniversityDurhamNC27708USA
| | - Jennifer R. Cochran
- Senior Associate Vice Provost for Research and Addie and Al Macovski Professor of Bioengineering, Shriram CenterStanford University Schools of Medicine and EngineeringStanfordCA94305USA
| | - Vicki Colvin
- Vernon K Krieble Professor of Chemistry and Professor of EngineeringBrown UniversityProvidenceRI02912USA
| | - Tejal A. Desai
- Sorensen Family Dean of Engineering and Professor of EngineeringBrown UniversityProvidenceRI02912USA
| | - James S. Duncan
- Ebenezer K. Hunt Professor and Chair of Biomedical Engineering, Professor of Radiology & Biomedical ImagingYale UniversityNew HavenCT06520USA
| | - Frederick H. Epstein
- Mac Wade Professor of Biomedical Engineering and Professor of Radiology and Medical Imaging, Associate Dean for ResearchSchool of Engineering and Applied ScienceCharlottesvilleVA22904USA
| | - Stephanie Fraley
- Associate Professor of BioengineeringUniversity of California San DiegoLa JollaCA92093-0412USA
| | - Cecilia Giachelli
- Steven R. and Connie R. Rogel Endowed Professor for Cardiovascular Innovation in BioengineeringAssociate Vice Provost for ResearchSeattleWA98195USA
| | - K. Jane Grande-Allen
- Isabel C. Cameron Professor of Bioengineering, Department of BioengineeringRice UniversityHoustonTX77005USA
| | - Jordan Green
- Biomedical Engineering and Vice Chair for Research and TranslationDepartment of Biomedical EngineeringBaltimoreMD21218USA
| | - X. Edward Guo
- Professor of Biomedical Engineering and Department ChairNew YorkNY10027USA
| | - Isaac B. Hilton
- Assistant Professor of Bioengineering and BioSciencesRice UniversityHoustonTX77005USA
- Department of BioengineeringBioscience Research CollaborativeHoustonTX77030USA
| | - Jay D. Humphrey
- John C. Malone Professor of Biomedical EngineeringYale UniversityNew HavenCT06511USA
| | - Chris R Johnson
- Distinguished Professor of Computer Science, Research Professor of BioengineeringUniversity of UtahSalt Lake CityUT84112-9205USA
| | - George Karniadakis
- The Charles Pitts Robinson and John Palmer Barstow Professor of Applied Mathematics and EngineeringBrown UniversityProvidenceRI02912USA
| | - Michael R. King
- J. Lawrence Wilson Professor of Engineering, Chair, Department of Biomedical Engineering, Professor of Biomedical Engineering, Professor of Radiology and Radiological Sciences5824 Stevenson CenterNashvilleTN351631-1631USA
| | - Robert F. Kirsch
- Allen H. and Constance T. Ford Professor and Chair of Biomedical EngineeringCase Western Reserve UniversityClevelandOH44106USA
- Department of Biomedical EngineeringClevelandOH4410USA
| | - Sanjay Kumar
- California Institute for Quantitative BiosciencesUC BerkeleyBerkeleyCA94720USA
| | - Cato T. Laurencin
- University Professor and Albert and Wilda Van Dusen Distinguished Endowed Professor of Orthopaedic Surgery, CEO, The Cato T. Laurencin Institute for Regenerative EngineeringUconnFarmingtonCT06030-3711USA
| | - Song Li
- Department of BioengineeringUCLA Samueli School of EngineeringLos AngelesCA90095USA
| | - Richard L. Lieber
- Chief Scientific Officer and Senior Vice President, Shirley Ryan Ability Lab, Professor of Physiology and Biomedical EngineeringNorthwestern UniversityEvanstonIL60208USAUSA
| | - Nigel Lovell
- Graduate School of Biomedical EngineeringUniversity of New South WalesSydneyNSW2052Australia
| | - Prashant Mali
- Professor of BioengineeringUniversity of California San DiegoLa JollaCA92093-0412USA
| | - Susan S. Margulies
- Wallace H. Coulter Chair and Professor of Biomedical EngineeringGeorgia Institute of Technology and Emory UniversityAtlantaGA30332USA
| | - David F. Meaney
- Professor and Senior Associate DeanPenn EngineeringPhiladelphiaPA19104-6391USA
| | - Brenda Ogle
- Department of Biomedical Engineering, Professor, Department of Pediatrics, Director, Stem Cell InstituteUniversity of Minnesota-Twin CitiesMinneapolisMN55455USA
| | - Bernhard Palsson
- Y.C. Fung Endowed Professor in Bioengineering, Professor of PediatricsUniversity of California San DiegoLa JollaCA92093-0412USA
| | - Nicholas A. Peppas
- Cockrell Family Regents Chair in Engineering, Director, Institute of Biomaterials, Drug Delivery and Regenerative Medicine, Professor, McKetta Department of Chemical Engineering, Department of Biomedical Engineering, Department of Pediatrics, Department of Surgery and Perioperative Care, Dell Medical School, and Division of Molecular Pharmaceutics and Drug Delivery, College of PharmacyThe University of Texas at AustinAustinTX78712-1801USA
| | - Eric J. Perreault
- Vice President for Research, Professor of Biomedical Engineering, Professor of Physical Medicine and RehabilitationNorthwestern UniversityEvanstonIL60208USA
| | - Rick Rabbitt
- Professor of Biomedical Engineering, Neuroscience ProgramSal Lake CityUT84112USA
| | - Lori A. Setton
- Department Chair, Lucy & Stanley Lopata Distinguished Professor of Biomedical EngineeringWashington University in St. Louis, McKelvey School of EngineeringSt. LouisMO63130USA
| | - Lonnie D. Shea
- Biomedical EngineeringUniversity of MichiganAnn ArborMI48109USA
| | - Sanjeev G. Shroff
- Distinguished Professor of and Gerald E. McGinnis Chair in Bioengineering, Professor of Medicine, Swanson School of EngineeringUniversity of PittsburghPittsburghPA15261USA
| | - Kirk Shung
- Professor Emeritus of Biomedical Engineering, Alfred E. Mann Department of Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA90089USA
| | | | | | - Shyni Varghese
- Professor of Biomedical Engineering, Mechanical Engineering & Materials Science and OrthopaedicsDuke UniversityDurhamNC27710USA
| | - Gordana Vunjak-Novakovic
- University and Mikati Foundation Professor of Biomedical Engineering and Medical SciencesColumbia UniversityNew YorkNY10027USA
| | - John A. White
- Professor and Chair Department of Biomedical EngineeringBoston UniversityBostonMA02215USA
| | - Raimond Winslow
- Director of Life Science and Medical Research; Professor of BioengineeringNortheastern UniversityPortlandME04101USA
| | - Jianyi Zhang
- Department of Biomedical Engineering, T. Michael and Gillian Goodrich Endowed Chair of Engineering Leadership, Professor of Medicine, of Engineering, School of Medicine, School of EngineeringUAB | The University of Alabama at BirminghamU.K.
| | - Kun Zhang
- Chair/Professor of BioengineeringUniversity of California San DiegoLa JollaCA92093-0412USA
| | - Charles Zukoski
- Shelly and Ofer Nemirovsky Provost's Chair and Professor of Chemical Engineering and Materials Science and Biomedical Engineering, Alfred E. Mann Department of Biomedical EngineeringUniversity of Southern CaliforniaLos AngelesCA90089USA
| | - Michael I. Miller
- Bessie Darling Massey Professor and Director, Department of Biomedical Engineering, Co-Director, Kavli Neuroscience Discovery InstituteJohns Hopkins University School of Medicine and Whiting School of EngineeringBaltimoreMD21218USA
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Vinnenberg L, Rychlik N, Oniani T, Williams B, White JA, Kovac S, Meuth SG, Budde T, Hundehege P. Assessing neuroprotective effects of diroximel fumarate and siponimod via modulation of pacemaker channels in an experimental model of remyelination. Exp Neurol 2024; 371:114572. [PMID: 37852467 DOI: 10.1016/j.expneurol.2023.114572] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [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: 09/06/2023] [Revised: 10/04/2023] [Accepted: 10/14/2023] [Indexed: 10/20/2023]
Abstract
Cuprizone (CPZ)-induced alterations in axonal myelination are associated with a period of neuronal hyperexcitability and increased activity of hyperpolarization-activated and cyclic nucleotide-gated (HCN) channels in the thalamocortical (TC) system. Substances used for the treatment of multiple sclerosis (MS) have been shown to normalize neuronal excitability in CPZ-treated mice. Therefore, we aimed to examine the effects of diroximel fumarate (DRF) and the sphingosine 1-phospate receptor (S1PR) modulator siponimod on action potential firing and the inward current (Ih) carried by HCN ion channels in naive conditions and during different stages of de- and remyelination. Here, DRF application reduced Ih current density in ex vivo patch clamp recordings from TC neurons of the ventrobasal thalamic complex (VB), thereby counteracting the increase of Ih during early remyelination. Siponimod reduced Ih in VB neurons under control conditions but had no effect in neurons of the auditory cortex (AU). Furthermore, siponimod increased and decreased AP firing properties of neurons in VB and AU, respectively. Computational modeling revealed that both DRF and siponimod influenced thalamic bursting during early remyelination by delaying the onset and decreasing the interburst frequency. Thus, substances used in MS treatment normalize excitability in the TC system by influencing AP firing and Ih.
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Affiliation(s)
- Laura Vinnenberg
- Department of Neurology with Institute of Translational Neurology, Münster University, Albert-Schweitzer-Campus 1, D-48149 Münster, Germany
| | - Nicole Rychlik
- Institute of Physiology I, Münster University, Robert-Koch-Str. 27a, D-48149 Münster, Germany.
| | - Tengiz Oniani
- Institute of Physiology I, Münster University, Robert-Koch-Str. 27a, D-48149 Münster, Germany
| | - Brandon Williams
- Department of Biomedical Engineering, Center for Systems Neuroscience, Neurophotonics Center, Boston University, 610 Commonwealth Ave, Boston MA-02215, USA
| | - John A White
- Department of Biomedical Engineering, Center for Systems Neuroscience, Neurophotonics Center, Boston University, 610 Commonwealth Ave, Boston MA-02215, USA
| | - Stjepana Kovac
- Department of Neurology with Institute of Translational Neurology, Münster University, Albert-Schweitzer-Campus 1, D-48149 Münster, Germany
| | - Sven G Meuth
- Neurology Clinic, Medical Faculty, University Clinic Düsseldorf, Moorenstraße 5, D-40225 Düsseldorf, Germany
| | - Thomas Budde
- Institute of Physiology I, Münster University, Robert-Koch-Str. 27a, D-48149 Münster, Germany
| | - Petra Hundehege
- Department of Neurology with Institute of Translational Neurology, Münster University, Albert-Schweitzer-Campus 1, D-48149 Münster, Germany
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Abramson S, Kraus BJ, White JA, Hasselmo ME, Derdikman D, Morris G. Flexible coding of time or distance in hippocampal cells. eLife 2023; 12:e83930. [PMID: 37842914 PMCID: PMC10712950 DOI: 10.7554/elife.83930] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 10/04/2022] [Accepted: 10/12/2023] [Indexed: 10/17/2023] Open
Abstract
Analysis of neuronal activity in the hippocampus of behaving animals has revealed cells acting as 'Time Cells', which exhibit selective spiking patterns at specific time intervals since a triggering event, and 'Distance Cells', which encode the traversal of specific distances. Other neurons exhibit a combination of these features, alongside place selectivity. This study aims to investigate how the task performed by animals during recording sessions influences the formation of these representations. We analyzed data from a treadmill running study conducted by Kraus et al., 2013, in which rats were trained to run at different velocities. The rats were recorded in two trial contexts: a 'fixed time' condition, where the animal ran on the treadmill for a predetermined duration before proceeding, and a 'fixed distance' condition, where the animal ran a specific distance on the treadmill. Our findings indicate that the type of experimental condition significantly influenced the encoding of hippocampal cells. Specifically, distance-encoding cells dominated in fixed-distance experiments, whereas time-encoding cells dominated in fixed-time experiments. These results underscore the flexible coding capabilities of the hippocampus, which are shaped by over-representation of salient variables associated with reward conditions.
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Affiliation(s)
- Shai Abramson
- Rappaport Faculty of Medicine and Research Institute, Technion - Israel Institute of TechnologyHaifaIsrael
| | - Benjamin J Kraus
- Center for Memory and Brain, Boston UniversityBostonUnited States
| | - John A White
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
| | | | - Dori Derdikman
- Rappaport Faculty of Medicine and Research Institute, Technion - Israel Institute of TechnologyHaifaIsrael
| | - Genela Morris
- Rappaport Faculty of Medicine and Research Institute, Technion - Israel Institute of TechnologyHaifaIsrael
- Tel Aviv Sourasky Medical CenterTel AvivIsrael
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Rahsepar B, Norman JF, Noueihed J, Lahner B, Quick MH, Ghaemi K, Pandya A, Fernandez FR, Ramirez S, White JA. Theta-phase-specific modulation of dentate gyrus memory neurons. eLife 2023; 12:e82697. [PMID: 37401757 PMCID: PMC10361715 DOI: 10.7554/elife.82697] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 07/03/2023] [Indexed: 07/05/2023] Open
Abstract
The theta rhythm, a quasi-periodic 4-10 Hz oscillation, is observed during memory processing in the hippocampus, with different phases of theta hypothesized to separate independent streams of information related to the encoding and recall of memories. At the cellular level, the discovery of hippocampal memory cells (engram neurons), as well as the modulation of memory recall through optogenetic activation of these cells, has provided evidence that certain memories are stored, in part, in a sparse ensemble of neurons in the hippocampus. In previous research, however, engram reactivation has been carried out using open-loop stimulation at fixed frequencies; the relationship between engram neuron reactivation and ongoing network oscillations has not been taken into consideration. To address this concern, we implemented a closed-loop reactivation of engram neurons that enabled phase-specific stimulation relative to theta oscillations in the local field potential in CA1. Using this real-time approach, we tested the impact of activating dentate gyrus engram neurons during the peak (encoding phase) and trough (recall phase) of theta oscillations. Consistent with previously hypothesized functions of theta oscillations in memory function, we show that stimulating dentate gyrus engram neurons at the trough of theta is more effective in eliciting behavioral recall than either fixed-frequency stimulation or stimulation at the peak of theta. Moreover, phase-specific trough stimulation is accompanied by an increase in the coupling between gamma and theta oscillations in CA1 hippocampus. Our results provide a causal link between phase-specific activation of engram cells and the behavioral expression of memory.
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Affiliation(s)
- Bahar Rahsepar
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
- Center for Systems Neuroscience, Neurophotonics Center, Boston UniversityBostonUnited States
- Department of Biology, Boston UniversityBostonUnited States
| | - Jacob F Norman
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
- Center for Systems Neuroscience, Neurophotonics Center, Boston UniversityBostonUnited States
| | - Jad Noueihed
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
- Center for Systems Neuroscience, Neurophotonics Center, Boston UniversityBostonUnited States
| | - Benjamin Lahner
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
| | - Melanie H Quick
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
| | - Kevin Ghaemi
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
| | - Aashna Pandya
- Department of Biology, Boston UniversityBostonUnited States
| | - Fernando R Fernandez
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
- Center for Systems Neuroscience, Neurophotonics Center, Boston UniversityBostonUnited States
| | - Steve Ramirez
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
- Center for Systems Neuroscience, Neurophotonics Center, Boston UniversityBostonUnited States
- Department of Psychological and Brain Sciences, Boston UniversityBostonUnited States
| | - John A White
- Department of Biomedical Engineering, Boston UniversityBostonUnited States
- Center for Systems Neuroscience, Neurophotonics Center, Boston UniversityBostonUnited States
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Via G, Baravalle R, Fernandez FR, White JA, Canavier CC. Interneuronal network model of theta-nested fast oscillations predicts differential effects of heterogeneity, gap junctions and short term depression for hyperpolarizing versus shunting inhibition. PLoS Comput Biol 2022; 18:e1010094. [PMID: 36455063 PMCID: PMC9747050 DOI: 10.1371/journal.pcbi.1010094] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 12/13/2022] [Accepted: 11/14/2022] [Indexed: 12/05/2022] Open
Abstract
Theta and gamma oscillations in the hippocampus have been hypothesized to play a role in the encoding and retrieval of memories. Recently, it was shown that an intrinsic fast gamma mechanism in medial entorhinal cortex can be recruited by optogenetic stimulation at theta frequencies, which can persist with fast excitatory synaptic transmission blocked, suggesting a contribution of interneuronal network gamma (ING). We calibrated the passive and active properties of a 100-neuron model network to capture the range of passive properties and frequency/current relationships of experimentally recorded PV+ neurons in the medial entorhinal cortex (mEC). The strength and probabilities of chemical and electrical synapses were also calibrated using paired recordings, as were the kinetics and short-term depression (STD) of the chemical synapses. Gap junctions that contribute a noticeable fraction of the input resistance were required for synchrony with hyperpolarizing inhibition; these networks exhibited theta-nested high frequency oscillations similar to the putative ING observed experimentally in the optogenetically-driven PV-ChR2 mice. With STD included in the model, the network desynchronized at frequencies above ~200 Hz, so for sufficiently strong drive, fast oscillations were only observed before the peak of the theta. Because hyperpolarizing synapses provide a synchronizing drive that contributes to robustness in the presence of heterogeneity, synchronization decreases as the hyperpolarizing inhibition becomes weaker. In contrast, networks with shunting inhibition required non-physiological levels of gap junctions to synchronize using conduction delays within the measured range.
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Affiliation(s)
- Guillem Via
- Louisiana State University Health Sciences Center, Department of Cell Biology and Anatomy, New Orleans, Louisiana, United States of America
| | - Roman Baravalle
- Louisiana State University Health Sciences Center, Department of Cell Biology and Anatomy, New Orleans, Louisiana, United States of America
| | - Fernando R. Fernandez
- Department of Biomedical Engineering, Center for Systems Neuroscience, Neurophotonics Center, Boston University, Boston, Massachusetts, United States of America
| | - John A. White
- Department of Biomedical Engineering, Center for Systems Neuroscience, Neurophotonics Center, Boston University, Boston, Massachusetts, United States of America
| | - Carmen C. Canavier
- Louisiana State University Health Sciences Center, Department of Cell Biology and Anatomy, New Orleans, Louisiana, United States of America
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Oniani T, Vinnenberg L, Chaudhary R, Schreiber JA, Riske K, Williams B, Pape HC, White JA, Junker A, Seebohm G, Meuth SG, Hundehege P, Budde T, Zobeiri M. Effects of Axonal Demyelination, Inflammatory Cytokines and Divalent Cation Chelators on Thalamic HCN Channels and Oscillatory Bursting. Int J Mol Sci 2022; 23:ijms23116285. [PMID: 35682964 PMCID: PMC9181513 DOI: 10.3390/ijms23116285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 04/27/2022] [Revised: 05/31/2022] [Accepted: 05/31/2022] [Indexed: 12/13/2022] Open
Abstract
Multiple sclerosis (MS) is a demyelinating disease of the central nervous system that is characterized by the progressive loss of oligodendrocytes and myelin and is associated with thalamic dysfunction. Cuprizone (CPZ)-induced general demyelination in rodents is a valuable model for studying different aspects of MS pathology. CPZ feeding is associated with the altered distribution and expression of different ion channels along neuronal somata and axons. However, it is largely unknown whether the copper chelator CPZ directly influences ion channels. Therefore, we assessed the effects of different divalent cations (copper; zinc) and trace metal chelators (EDTA; Tricine; the water-soluble derivative of CPZ, BiMPi) on hyperpolarization-activated cyclic nucleotide-gated (HCN) channels that are major mediators of thalamic function and pathology. In addition, alterations of HCN channels induced by CPZ treatment and MS-related proinflammatory cytokines (IL-1β; IL-6; INF-α; INF-β) were characterized in C57Bl/6J mice. Thus, the hyperpolarization-activated inward current (Ih) was recorded in thalamocortical (TC) neurons and heterologous expression systems (mHCN2 expressing HEK cells; hHCN4 expressing oocytes). A number of electrophysiological characteristics of Ih (potential of half-maximal activation (V0.5); current density; activation kinetics) were unchanged following the extracellular application of trace metals and divalent cation chelators to native neurons, cell cultures or oocytes. Mice were fed a diet containing 0.2% CPZ for 35 days, resulting in general demyelination in the brain. Withdrawal of CPZ from the diet resulted in rapid remyelination, the effects of which were assessed at three time points after stopping CPZ feeding (Day1, Day7, Day25). In TC neurons, Ih was decreased on Day1 and Day25 and revealed a transient increased availability on Day7. In addition, we challenged naive TC neurons with INF-α and IL-1β. It was found that Ih parameters were differentially altered by the application of the two cytokines to thalamic cells, while IL-1β increased the availability of HCN channels (depolarized V0.5; increased current density) and the excitability of TC neurons (depolarized resting membrane potential (RMP); increased the number of action potentials (APs); produced a larger voltage sag; promoted higher input resistance; increased the number of burst spikes; hyperpolarized the AP threshold), INF-α mediated contrary effects. The effect of cytokine modulation on thalamic bursting was further assessed in horizontal slices and a computational model of slow thalamic oscillations. Here, IL-1β and INF-α increased and reduced oscillatory bursting, respectively. We conclude that HCN channels are not directly modulated by trace metals and divalent cation chelators but are subject to modulation by different MS-related cytokines.
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Affiliation(s)
- Tengiz Oniani
- Institute of Physiology I, Westfälische Wilhelms-Universität, Robert-Koch-Str. 27a, D-48149 Münster, Germany; (T.O.); (R.C.); (H.-C.P.); (M.Z.)
| | - Laura Vinnenberg
- Department of Neurology with Institute of Translational Neurology, Albert-Schweitzer-Campus 1, D-48149 Münster, Germany; (L.V.); (P.H.)
| | - Rahul Chaudhary
- Institute of Physiology I, Westfälische Wilhelms-Universität, Robert-Koch-Str. 27a, D-48149 Münster, Germany; (T.O.); (R.C.); (H.-C.P.); (M.Z.)
| | - Julian A. Schreiber
- Institute of Pharmaceutical and Medicinal Chemistry, Westfälische Wilhelms-Universität, Corren-Str. 48, D-48149 Münster, Germany;
- Cellular Electrophysiology and Molecular Biology, Department of Cardiovascular Medicine, Institute for Genetics of Heart Diseases (IfGH), University Hospital Münster, Robert-Koch-Str. 45, D-48149 Münster, Germany;
| | - Kathrin Riske
- European Institute for Molecular Imaging (EIMI), Westfälische Wilhelms-Universität, Waldeyer-Str. 15, D-48149 Münster, Germany; (K.R.); (A.J.)
| | - Brandon Williams
- Center for Systems Neuroscience, Neurophotonics Center, Department of Biomedical Engineering, Boston University, 610 Commonwealth Ave., Boston, MA 02215, USA; (B.W.); (J.A.W.)
| | - Hans-Christian Pape
- Institute of Physiology I, Westfälische Wilhelms-Universität, Robert-Koch-Str. 27a, D-48149 Münster, Germany; (T.O.); (R.C.); (H.-C.P.); (M.Z.)
| | - John A. White
- Center for Systems Neuroscience, Neurophotonics Center, Department of Biomedical Engineering, Boston University, 610 Commonwealth Ave., Boston, MA 02215, USA; (B.W.); (J.A.W.)
| | - Anna Junker
- European Institute for Molecular Imaging (EIMI), Westfälische Wilhelms-Universität, Waldeyer-Str. 15, D-48149 Münster, Germany; (K.R.); (A.J.)
| | - Guiscard Seebohm
- Cellular Electrophysiology and Molecular Biology, Department of Cardiovascular Medicine, Institute for Genetics of Heart Diseases (IfGH), University Hospital Münster, Robert-Koch-Str. 45, D-48149 Münster, Germany;
| | - Sven G. Meuth
- Neurology Clinic, University Clinic Düsseldorf, Moorenstraße 5, D-40225 Düsseldorf, Germany;
| | - Petra Hundehege
- Department of Neurology with Institute of Translational Neurology, Albert-Schweitzer-Campus 1, D-48149 Münster, Germany; (L.V.); (P.H.)
| | - Thomas Budde
- Institute of Physiology I, Westfälische Wilhelms-Universität, Robert-Koch-Str. 27a, D-48149 Münster, Germany; (T.O.); (R.C.); (H.-C.P.); (M.Z.)
- Correspondence:
| | - Mehrnoush Zobeiri
- Institute of Physiology I, Westfälische Wilhelms-Universität, Robert-Koch-Str. 27a, D-48149 Münster, Germany; (T.O.); (R.C.); (H.-C.P.); (M.Z.)
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8
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González-Ayala J, Calvo Hernández A, White JA, Medina A, Roco JMM, Velasco S. Success versus failure: Efficient heat devices in thermodynamics. Phys Rev E 2022; 105:014115. [PMID: 35193266 DOI: 10.1103/physreve.105.014115] [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: 09/28/2021] [Accepted: 12/24/2021] [Indexed: 06/14/2023]
Abstract
Classical equilibrium thermodynamics provides, in a general way, upper Carnot bounds for the performance of energy converters. Nevertheless, to suggest lower bounds is a much more subtle issue, especially when they are related to a definition of convenience. Here, this issue is investigated in a unified way for heat engines, refrigerators, and heat pumps. First, irreversibilities are weighted in the context of heat reservoir stability for irreversible engines by using the thermodynamic distance between minimum energy and maximum entropy steady states. Some stability coefficients can be related to a majorization process and the obtention of Pareto fronts, linking stability and optimization by means of efficiency and entropy due to correlations between system and reservoirs. Second, these findings are interpreted in a very simple context. A region where the heat device is efficient is defined in a general scheme and, below this zone, the heat device is inefficient in the sense that irreversibilities somehow dominate its behavior. These findings allow for a clearer understanding of the role played by some well-known figures of merit in the scope of finite-time and -size optimization. Comparison with experimental results is provided.
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Affiliation(s)
- J González-Ayala
- Departamento de Física Aplicada and Instituto Universitario de Física y Matemáticas (IUFFYM), Universidad de Salamanca, 37008 Salamanca, Spain
| | - A Calvo Hernández
- Departamento de Física Aplicada and Instituto Universitario de Física y Matemáticas (IUFFYM), Universidad de Salamanca, 37008 Salamanca, Spain
| | - J A White
- Departamento de Física Aplicada and Instituto Universitario de Física y Matemáticas (IUFFYM), Universidad de Salamanca, 37008 Salamanca, Spain
| | - A Medina
- Departamento de Física Aplicada and Instituto Universitario de Física y Matemáticas (IUFFYM), Universidad de Salamanca, 37008 Salamanca, Spain
| | - J M M Roco
- Departamento de Física Aplicada and Instituto Universitario de Física y Matemáticas (IUFFYM), Universidad de Salamanca, 37008 Salamanca, Spain
| | - S Velasco
- Departamento de Física Aplicada and Instituto Universitario de Física y Matemáticas (IUFFYM), Universidad de Salamanca, 37008 Salamanca, Spain
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9
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Labib D, Dykstra S, Satriano A, Mikami Y, Prosia E, Flewitt J, Howarth AG, Lydell CP, Kolman L, Paterson DI, Oudit GY, Pituskin E, Cheung WY, Lee J, White JA. Prevalence and predictors of right ventricular dysfunction in cancer patients treated with cardiotoxic chemotherapy – a prospective cardiovascular magnetic resonance study. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.2878] [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: 11/13/2022] Open
Abstract
Abstract
Background
Right ventricular (RV) function has an established incremental prognostic value in cardiomyopathy. Studies on cancer therapeutics-related cardiac dysfunction (CTRCD) primarily focused on the left ventricle (LV), with conflicting results from small studies dedicated to RV dysfunction.
Purpose
We sought to investigate the influence of chemotherapy on RV function relative to LV function using serial cardiac magnetic resonance (CMR).
Methods
Patients were enrolled as part of Cardiotoxicity Prevention Research Initiative (CAPRI) Registry aimed at evaluating CMR-based markers for surveillance of CTRCD. Patients underwent non-contrast CMR imaging prior to initiation of anthracyclines and/or trastuzumab and serially every 3 months during the first year, then annually thereafter. We included patients who had a baseline and ≥1 follow-up scan and excluded those with baseline LV ejection fraction (EF)<50%, providing 320 patients completing 1,453 CMR studies. Cine images were analysed to calculate chamber volumes indexed to body surface area and EF. We defined LV CTRCD using CMR modality specific criteria of a drop in LV EF ≥5% from baseline to <57%; RV CTRCD as a drop ≥5% to <49% in females and <47% in males. We used linear mixed models to study the changes in ventricular volumes and EF with time.
Results
The majority of patients were females (80%), had breast cancer (68%) or lymphoma (32%), with a mean age of 52.7±13 years. Figure 1 shows temporal changes in mean ventricular volumes and function over the first year. Mean changes in RV function followed those of the LV, with the nadir of EF and maximum of volumes occurring at 6 months. Respective values for mean decrease in LV and RV EF at this time point versus baseline were 4.1 and 2.9% (p<0.001). Concomitant mean increase in indexed RV end-diastolic (ED) and end-systolic (ES) volumes were 1.6 and 2.7 ml/m2 (p=0.2 and <0.001). There was significant interaction of chemotherapy regimen with time for RV volumes (p=0.001 and 0.003), but not RV EF (p=0.7), with worst changes occurring with combined anthracyclines and trastuzumab. In all, 70 (22%) and 28 (9%) patients met criteria for LV and RV CTRCD, respectively. Among those who developed RV CTRCD, 10 had persistently normal LV function. Figure 2 shows the results of logistic regression to predict RV CTRCD. Significant univariable predictors included combined chemotherapy regimen and baseline LV and RV volumes and LV EF. Adjusting for age, sex, and chemotherapy regimen, baseline RV ED volume remained associated with RV CTRCD (odds ratio 1.6; p=0.005).
Conclusion
In this large study, RV volumes and function were similarly influenced by chemotherapy versus comparable LV-based measures. Using similar threshold criteria, the incidence of RV CTRCD was lower than for LV CTRCD; however, one third of those who develop RV CTRCD showed normal LV function. Future studies are warranted to study the prognostic influence of RV injury in cancer patients.
Funding Acknowledgement
Type of funding sources: Other. Main funding source(s): Alberta InnovatesGenome Alberta Figure 1. Temporal changes in LV & RV functionFigure 2. Predictors of RV CTRCD
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Affiliation(s)
- D Labib
- Libin Cardiovascular Institute of Alberta, Stephenson Cardiac Imaging Centre, Calgary, Canada
| | - S Dykstra
- Libin Cardiovascular Institute of Alberta, Stephenson Cardiac Imaging Centre, Calgary, Canada
| | - A Satriano
- Libin Cardiovascular Institute of Alberta, Stephenson Cardiac Imaging Centre, Calgary, Canada
| | - Y Mikami
- Libin Cardiovascular Institute of Alberta, Stephenson Cardiac Imaging Centre, Calgary, Canada
| | - E Prosia
- Libin Cardiovascular Institute of Alberta, Stephenson Cardiac Imaging Centre, Calgary, Canada
| | - J Flewitt
- Libin Cardiovascular Institute of Alberta, Stephenson Cardiac Imaging Centre, Calgary, Canada
| | - A G Howarth
- Libin Cardiovascular Institute of Alberta, Stephenson Cardiac Imaging Centre, Calgary, Canada
| | - C P Lydell
- Libin Cardiovascular Institute of Alberta, Stephenson Cardiac Imaging Centre, Calgary, Canada
| | - L Kolman
- Libin Cardiovascular Institute of Alberta, Stephenson Cardiac Imaging Centre, Calgary, Canada
| | - D I Paterson
- University of Alberta, Department of Medicine, Edmonton, Canada
| | - G Y Oudit
- University of Alberta, Department of Medicine, Edmonton, Canada
| | - E Pituskin
- University of Alberta, Department of Oncology, Edmonton, Canada
| | - W Y Cheung
- University of Calgary, Department of Oncology, Calgary, Canada
| | - J Lee
- University of Calgary, Departments of Community Health Sciences & Cardiac Sciences, Calgary, Canada
| | - J A White
- Libin Cardiovascular Institute of Alberta, Stephenson Cardiac Imaging Centre, Calgary, Canada
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10
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Shi L, Jiang Y, Fernandez FR, Chen G, Lan L, Man HY, White JA, Cheng JX, Yang C. Non-genetic photoacoustic stimulation of single neurons by a tapered fiber optoacoustic emitter. Light Sci Appl 2021; 10:143. [PMID: 34257273 PMCID: PMC8277806 DOI: 10.1038/s41377-021-00580-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 06/09/2021] [Accepted: 06/21/2021] [Indexed: 05/19/2023]
Abstract
Neuromodulation at high spatial resolution poses great significance in advancing fundamental knowledge in the field of neuroscience and offering novel clinical treatments. Here, we developed a tapered fiber optoacoustic emitter (TFOE) generating an ultrasound field with a high spatial precision of 39.6 µm, enabling optoacoustic activation of single neurons or subcellular structures, such as axons and dendrites. Temporally, a single acoustic pulse of sub-microsecond converted by the TFOE from a single laser pulse of 3 ns is shown as the shortest acoustic stimuli so far for successful neuron activation. The precise ultrasound generated by the TFOE enabled the integration of the optoacoustic stimulation with highly stable patch-clamp recording on single neurons. Direct measurements of the electrical response of single neurons to acoustic stimulation, which is difficult for conventional ultrasound stimulation, have been demonstrated. By coupling TFOE with ex vivo brain slice electrophysiology, we unveil cell-type-specific responses of excitatory and inhibitory neurons to acoustic stimulation. These results demonstrate that TFOE is a non-genetic single-cell and sub-cellular modulation technology, which could shed new insights into the mechanism of ultrasound neurostimulation.
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Affiliation(s)
- Linli Shi
- Department of Chemistry, Boston University, 580 Commonwealth Avenue, Boston, MA, 02215, USA
| | - Ying Jiang
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA, 02215, USA
| | - Fernando R Fernandez
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA, 02215, USA
- Center for Systems Neuroscience, Boston University, 610 Commonwealth Ave, Boston, MA, 02215, USA
- Neurophotonics Center, Photonics Center, Boston University, 8 St. Mary's Street, Boston, MA, 02215, USA
| | - Guo Chen
- Department of Electrical and Computer Engineering, 8 St. Mary's Street, Boston, MA, 02215, USA
| | - Lu Lan
- Department of Electrical and Computer Engineering, 8 St. Mary's Street, Boston, MA, 02215, USA
| | - Heng-Ye Man
- Center for Systems Neuroscience, Boston University, 610 Commonwealth Ave, Boston, MA, 02215, USA
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA
| | - John A White
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA, 02215, USA
- Center for Systems Neuroscience, Boston University, 610 Commonwealth Ave, Boston, MA, 02215, USA
- Neurophotonics Center, Photonics Center, Boston University, 8 St. Mary's Street, Boston, MA, 02215, USA
| | - Ji-Xin Cheng
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA, 02215, USA.
- Department of Electrical and Computer Engineering, 8 St. Mary's Street, Boston, MA, 02215, USA.
| | - Chen Yang
- Department of Chemistry, Boston University, 580 Commonwealth Avenue, Boston, MA, 02215, USA.
- Department of Electrical and Computer Engineering, 8 St. Mary's Street, Boston, MA, 02215, USA.
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11
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Norman JF, Rahsepar B, Noueihed J, White JA. Determining the optimal expression method for dual-color imaging. J Neurosci Methods 2020; 351:109064. [PMID: 33387574 DOI: 10.1016/j.jneumeth.2020.109064] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/11/2020] [Accepted: 12/23/2020] [Indexed: 11/30/2022]
Abstract
BACKGROUND Fluorescence imaging is a widely used technique that permits for cell-type-specific recording from hundreds of neurons simultaneously. Often, to obtain cell-type-specific recordings from more than one cell type, researchers add an additional fluorescent protein to mark a second neuronal subpopulation. Currently, however, no consensus exists on the best expression method for multiple fluorescent proteins. NEW METHOD We optimized the coexpression of two fluorescent proteins across multiple brain regions and mouse lines. RESULTS The single-virus method, a viral injection in a double transgenic reporter mouse, results in limited fluorescent coexpression. In contrast the double-virus method, injecting a mixture of two viruses in a Cre driver mouse, results in up to 70 % coexpression of the fluorescent markers in vitro. Using the double-virus method allows for population activity recording and neuronal subpopulation determination. COMPARISON WITH EXISTING METHOD The standard for expressing two fluorescent proteins is to use a double transgenic reporter mouse with a single viral injection. Injecting two viruses into a Cre driver mouse resulted in significantly higher coexpression compared to the standard method. This result generalized to multiple brain regions and mouse lines in vitro, as well as in vivo. CONCLUSION Efficiently coexpressing multiple fluorescent proteins provides population activity while identifying a neuronal subpopulation of interest. The improved coexpression is applicable to a wide breadth of experiments, ranging from engram investigation to voltage imaging.
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Affiliation(s)
- Jacob F Norman
- Dept. of Biomedical Engineering, Center for Systems Neuroscience, Neurophotonics Center, Boston University, Boston, MA, 02215, United States.
| | - Bahar Rahsepar
- Dept. of Biomedical Engineering, Center for Systems Neuroscience, Neurophotonics Center, Boston University, Boston, MA, 02215, United States
| | - Jad Noueihed
- Dept. of Biomedical Engineering, Center for Systems Neuroscience, Neurophotonics Center, Boston University, Boston, MA, 02215, United States
| | - John A White
- Dept. of Biomedical Engineering, Center for Systems Neuroscience, Neurophotonics Center, Boston University, Boston, MA, 02215, United States
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12
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Shroff SN, Das SL, Tseng HA, Noueihed J, Fernandez F, White JA, Chen CS, Han X. Voltage Imaging of Cardiac Cells and Tissue Using the Genetically Encoded Voltage Sensor Archon1. iScience 2020; 23:100974. [PMID: 32299055 PMCID: PMC7160579 DOI: 10.1016/j.isci.2020.100974] [Citation(s) in RCA: 4] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 02/21/2020] [Accepted: 03/05/2020] [Indexed: 01/19/2023] Open
Abstract
Precise measurement of action potentials (APs) is needed to observe electrical activity and cellular communication within cardiac tissue. Voltage-sensitive dyes (VSDs) are traditionally used to measure cardiac APs; however, they require acute chemical addition that prevents chronic imaging. Genetically encoded voltage indicators (GEVIs) enable long-term studies of APs without the need of chemical additions, but current GEVIs used in cardiac tissue exhibit poor kinetics and/or low signal to noise (SNR). Here, we demonstrate the use of Archon1, a recently developed GEVI, in hiPSC-derived cardiomyocytes (CMs). When expressed in CMs, Archon1 demonstrated fast kinetics comparable with patch-clamp electrophysiology and high SNR significantly greater than the VSD Di-8-ANEPPS. Additionally, Archon1 enabled monitoring of APs across multiple cells simultaneously in 3D cardiac tissues. These results highlight Archon1's capability to investigate the electrical activity of CMs in a variety of applications and its potential to probe functionally complex in vitro models, as well as in vivo systems. Genetic sensor Archon1 reports membrane voltage in hiPSC-derived cardiomyocytes Archon1 monitors action potentials in 2D and 3D cardiac tissue with high sensitivity Archon1 repeatedly monitored voltage in the same cells and over extended time periods Voltage dynamics of multiple cells were recorded simultaneously with Archon1
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Affiliation(s)
- Sanaya N Shroff
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Shoshana L Das
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA; Harvard-MIT Program in Health Sciences and Technology, Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA
| | - Hua-An Tseng
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Jad Noueihed
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Fernando Fernandez
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - John A White
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Christopher S Chen
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA; Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA.
| | - Xue Han
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
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13
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White JA, Gaver DP, Butera RJ, Choi B, Dunlop MJ, Grande-Allen KJ, Grosberg A, Hitchcock RW, Huang-Saad AY, Kotche M, Kyle AM, Lerner AL, Linehan JH, Linsenmeier RA, Miller MI, Papin JA, Setton L, Sgro A, Smith ML, Zaman M, Lee AP. Core Competencies for Undergraduates in Bioengineering and Biomedical Engineering: Findings, Consequences, and Recommendations. Ann Biomed Eng 2020; 48:905-912. [DOI: 10.1007/s10439-020-02468-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 01/23/2020] [Indexed: 11/24/2022]
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14
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Clarkson C, Smeal RM, Hasenoehrl MG, White JA, Rubio ME, Wilcox KS. Ultrastructural and functional changes at the tripartite synapse during epileptogenesis in a model of temporal lobe epilepsy. Exp Neurol 2020; 326:113196. [PMID: 31935368 DOI: 10.1016/j.expneurol.2020.113196] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 01/10/2020] [Indexed: 12/27/2022]
Abstract
The persistent unresponsiveness of many of the acquired epilepsies to traditional antiseizure medications has motivated the search for prophylactic drug therapies that could reduce the incidence of epilepsy in this at risk population. These studies are based on the idea of a period of epileptogenesis that can follow a wide variety of brain injuries. Epileptogenesis is hypothesized to involve changes in the brain not initially associated with seizures, but which result finally in seizure prone networks. Understanding these changes will provide crucial clues for the development of prophylactic drugs. Using the repeated low-dose kainate rat model of epilepsy, we have studied the period of epileptogenesis following status epilepticus, verifying the latent period with continuous EEG monitoring. Focusing on ultrastructural properties of the tripartite synapse in the CA1 region of hippocampus we found increased astrocyte ensheathment around both the presynaptic and postsynaptic elements, reduced synaptic AMPA receptor subunit and perisynaptic astrocyte GLT-1 expression, and increased number of docked vesicles at the presynaptic terminal. These findings were associated with an increase in frequency of the mEPSCs observed in patch clamp recordings of CA1 pyramidal cells. The results suggest a complex set of changes, some of which have been associated with increasingly excitable networks such as increased vesicles and mEPSC frequency, and some associated with compensatory mechanisms, such as increased astrocyte ensheathment. The diversity of ultrastructural and electrophysiological changes observed during epileptogeneiss suggests that potential drug targets for this period should be broadened to include all components of the tripartite synapse.
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Affiliation(s)
- Cheryl Clarkson
- Dept. of Neurobiology, Univ. of Pittsburgh School of Medicine, Pittsburgh, PA 15261, United States of America
| | - Roy M Smeal
- Dept. of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT 84112, United States of America
| | - Meredith G Hasenoehrl
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT 84112, United States of America
| | - John A White
- Dept. of Biomedical Engineering, Boston University, Boston, MA 02215, United States of America
| | - Maria E Rubio
- Dept. of Neurobiology, Univ. of Pittsburgh School of Medicine, Pittsburgh, PA 15261, United States of America; Dept. of Otolaryngology, Univ. of Pittsburgh, Pittsburgh, PA 15261, United States of America.
| | - Karen S Wilcox
- Dept. of Pharmacology & Toxicology, University of Utah, Salt Lake City, UT 84112, United States of America; Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT 84112, United States of America.
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15
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White JA, Han X. Editorial overview: high-resolution brain cell imaging. Current Opinion in Biomedical Engineering 2019. [DOI: 10.1016/j.cobme.2019.12.004] [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: 10/25/2022]
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16
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Lei L, Satriano A, Magyar-Ng M, Mikami Y, Kalmady SV, Hoehn B, Dykstra S, Heydari B, Flewitt J, Merchant N, Howarth AG, Lydell CP, Greiner R, Fine NM, White JA. 4941Machine learning based automated diagnosis of ischemic vs non-ischemic dilated cardiomyopathy using 3D myocardial deformation analysis. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.0011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [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: 11/13/2022] Open
Abstract
Abstract
Background
Late Gadolinium Enhancement (LGE) imaging is a reference standard technique for the differentiation of ischemic cardiomyopathy (ICM) from non-ischemic dilated cardiomyopathy (NIDCM) in patients with heart failure and reduced ejection fraction (HFrEF). 3D myocardial deformation analysis (3D-MDA) offers highly reproducible phenotypic assessments of regional architecture and function that may provide value for artificial-intelligence-assisted cardiomyopathy diagnosis without need for LGE imaging.
Purpose
In this study, we trained and validated a machine-learning-based model to enable automated diagnosis of ischemic versus non-ischemic dilated cardiomyopathy exclusively using regional patterns of deformation among patients otherwise matched by age, sex and global contractile dysfunction.
Methods
100 ICM and 100 NIDCM patients matched for age, sex, and LVEF underwent standard cine SSFP and LGE imaging. Patient diagnoses were established using a combination of clinical and LGE-based criteria. 3D-MDA was performed using validated software (GIUSEPPE) to compute regional 3D strain measures at each cardiac phase in both conventional and principal strain directions. Principal Component Analysis (PCA) was performed on the composite 3D-MDA dataset. The first 20 components were chosen, accounting for approximately 65% of the population variance. Subsequently, a support-vector-machine-based algorithm was used with 10-fold cross-validation to discriminate ICM from NIDCM.
Results
Patients were 63±10 years (ICM: 63±10 years, NIDCM: 63±10 years, p=0.955), 74% male (ICM: 74%, NIDCM: 74%, p=1.000), and had a mean LVEF of 27±8% (ICM: 27±7%, NIDCM: 28±7%, p=0.688). Global time to peak strain was significantly shorter in ICM patients relative to NIDCM patients across all surfaces and in all directions (p<0.05). The highest single-variable Area Under the Curve (AUC) achieved for the classification of ICM versus NIDCM from global data was for minimum principal strain (ICM: 43.7±7.8, NIDCM: 48.3±7.5, p<0.001, AUC: 0.682) (Figure 1). However, a multi-feature machine-learning-based model exposed to all available regional 3D deformation data achieved an AUC of 0.903 (sensitivity 87.7%, specificity 75.5%).
Conclusions
Machine learning-based analyses of3D regionaldeformation patterns allows for robust discrimination of ICM versus NIDCM. Further expansion of the presented findings is planned on a wider, multi-centre cohort.
Acknowledgement/Funding
Dr. White was supported by an award from Heart and Stroke Foundation of Alberta. This study was funded in part by Calgary Health Trust.
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Affiliation(s)
- L Lei
- University of Calgary Foothills Hospital, Calgary, Canada
| | - A Satriano
- University of Calgary Foothills Hospital, Calgary, Canada
| | - M Magyar-Ng
- University of Calgary Foothills Hospital, Calgary, Canada
| | - Y Mikami
- University of Calgary Foothills Hospital, Calgary, Canada
| | - S V Kalmady
- University of Alberta, Computing Science, Edmonton, Canada
| | - B Hoehn
- University of Alberta, Computing Science, Edmonton, Canada
| | - S Dykstra
- University of Calgary Foothills Hospital, Calgary, Canada
| | - B Heydari
- University of Calgary Foothills Hospital, Calgary, Canada
| | - J Flewitt
- University of Calgary Foothills Hospital, Calgary, Canada
| | - N Merchant
- University of Calgary Foothills Hospital, Calgary, Canada
| | - A G Howarth
- University of Calgary Foothills Hospital, Calgary, Canada
| | - C P Lydell
- University of Calgary Foothills Hospital, Calgary, Canada
| | - R Greiner
- University of Alberta, Computing Science, Edmonton, Canada
| | - N M Fine
- University of Calgary Foothills Hospital, Calgary, Canada
| | - J A White
- University of Calgary Foothills Hospital, Calgary, Canada
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17
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Royzen F, Williams S, Fernandez FR, White JA. Balanced synaptic currents underlie low-frequency oscillations in the subiculum. Hippocampus 2019; 29:1178-1189. [PMID: 31301195 DOI: 10.1002/hipo.23131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 01/17/2019] [Revised: 06/06/2019] [Accepted: 06/07/2019] [Indexed: 12/31/2022]
Abstract
Numerous synaptic and intrinsic membrane mechanisms have been proposed for generating oscillatory activity in the hippocampus. Few studies, however, have directly measured synaptic conductances and membrane properties during oscillations. The time course and relative contribution of excitatory and inhibitory synaptic conductances, as well as the role of intrinsic membrane properties in amplifying synaptic inputs, remains unclear. To address this issue, we used an isolated whole hippocampal preparation that generates autonomous low-frequency oscillations near the theta range. Using 2-photon microscopy and expression of genetically encoded fluorophores, we obtained on-cell and whole-cell patch recordings of pyramidal cells and fast-firing interneurons in the distal subiculum. Pyramidal cell and interneuron spiking shared similar phase-locking to local field potential oscillations. In pyramidal cells, spiking resulted from a concomitant and balanced increase in excitatory and inhibitory synaptic currents. In contrast, interneuron spiking was driven almost exclusively by excitatory synaptic current. Thus, similar to tightly balanced networks underlying hippocampal gamma oscillations and ripples, balanced synaptic inputs in the whole hippocampal preparation drive highly phase-locked spiking at the peak of slower network oscillations.
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Affiliation(s)
- Feliks Royzen
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, Utah.,Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Sylvain Williams
- Department of Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Fernando R Fernandez
- Department of Biomedical Engineering, Center for Systems Neuroscience, Boston University, Boston, Massachusetts
| | - John A White
- Department of Biomedical Engineering, Center for Systems Neuroscience, Boston University, Boston, Massachusetts
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18
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de Vries HJC, de Barbeyrac B, de Vrieze NHN, Viset JD, White JA, Vall-Mayans M, Unemo M. 2019 European guideline on the management of lymphogranuloma venereum. J Eur Acad Dermatol Venereol 2019; 33:1821-1828. [PMID: 31243838 DOI: 10.1111/jdv.15729] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 05/17/2019] [Indexed: 11/26/2022]
Abstract
New or important issues in this updated version of the 2013 European guideline on the management of lymphogranuloma venereum (LGV): EPIDEMIOLOGY: Lymphogranuloma venereum continues to be endemic among European men who have sex with men (MSM) since 2003. Lymphogranuloma venereum infections in heterosexuals are extremely rare in Europe, and there is no evidence of transmission of LGV in the European heterosexual population. AETIOLOGY AND TRANSMISSION Chlamydia trachomatis serovars/genovars L2b and L2 are the causative strains in the majority of cases in Europe. CLINICAL FEATURES Among MSM, about 25% of the anorectal LGV infections are asymptomatic. Genital infections among MSM are rare; the ratio of genital vs. anorectal LGV infections is 1 in 15. DIAGNOSIS To diagnose LGV, a sample tested C. trachomatis positive with a commercial nucleic acid amplification test (NAAT) platform should be confirmed with an LGV discriminatory NAAT. TREATMENT Doxycycline 100 mg twice a day orally for 21 days is the recommended treatment for LGV. This same treatment is recommended also in asymptomatic patients and contacts of LGV patients. If another regimen is used, a test of cure (TOC) must be performed.
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Affiliation(s)
- H J C de Vries
- STI Outpatient Clinic, Infectious Diseases Department, Public Health Service Amsterdam, Amsterdam, The Netherlands.,Department of Dermatology, Amsterdam Institute for Infection and Immunity (AI&II), Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - B de Barbeyrac
- Mycoplasmal and Chlamydial Infections in Humans, University of Bordeaux, Bordeaux, France.,Mycoplasmal and Chlamydial Infections in Humans, INRA, Bordeaux, France.,Centre Hospitalier Universitaire de Bordeaux, Laboratoire de Bacteriologie, French National Reference Center for Bacterial STIs, Bordeaux, France
| | - N H N de Vrieze
- Department of Dermatology, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - J D Viset
- Department of Dermatology, Amsterdam Institute for Infection and Immunity (AI&II), Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - J A White
- Department of Genitourinary Medicine, Western Health & Social Care Trust, Londonderry, UK
| | - M Vall-Mayans
- STI Unit Vall d'Hebron-Drassanes, Department of Infectious Diseases, Hospital Vall d'Hebron, Barcelona, Spain
| | - M Unemo
- WHO Collaborating Centre for Gonorrhoea and Other Sexually Transmitted Infections, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
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19
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Melonakos ED, White JA, Fernandez FR. A model of cholinergic suppression of hippocampal ripples through disruption of balanced excitation/inhibition. Hippocampus 2018; 29:773-786. [PMID: 30417958 DOI: 10.1002/hipo.23051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 02/24/2018] [Revised: 10/02/2018] [Accepted: 10/31/2018] [Indexed: 11/11/2022]
Abstract
Sharp wave-ripples (140-220 Hz) are patterns of brain activity observed in the local field potential of the hippocampus which are present during memory consolidation. As rodents switch from memory consolidation to memory encoding behaviors, cholinergic inputs to the hippocampus from neurons in the medial septum-diagonal band of Broca cause a marked reduction in ripple incidence. The mechanism for this disruption in ripple power is not fully understood. In isolated neurons, the major effect of cholinergic input on hippocampal neurons is depolarization of the membrane potential, which affects both hippocampal pyramidal neurons and inhibitory interneurons. Using an existing model of ripple-frequency oscillations that includes both pyramidal neurons and interneurons, we investigated the mechanism whereby depolarizing inputs to these neurons can affect ripple power and frequency. We observed that ripple power and frequency are maintained, as long as inputs to pyramidal neurons and interneurons are balanced. Preferential drive to pyramidal neurons or interneurons, however, affects ripple power and can disrupt ripple oscillations by pushing ripple frequency higher or lower. Thus, an imbalance in drive to pyramidal neurons and interneurons provides a means whereby cholinergic input can suppress hippocampal ripples.
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Affiliation(s)
- Eric D Melonakos
- Department of Bioengineering, University of Utah, Salt Lake City, Utah
| | - John A White
- Department of Bioengineering, University of Utah, Salt Lake City, Utah.,Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Fernando R Fernandez
- Department of Bioengineering, University of Utah, Salt Lake City, Utah.,Department of Biomedical Engineering, Boston University, Boston, Massachusetts
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20
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Fernandez FR, Rahsepar B, White JA. Differences in the Electrophysiological Properties of Mouse Somatosensory Layer 2/3 Neurons In Vivo and Slice Stem from Intrinsic Sources Rather than a Network-Generated High Conductance State. eNeuro 2018; 5:ENEURO.0447-17.2018. [PMID: 29662946 PMCID: PMC5898699 DOI: 10.1523/eneuro.0447-17.2018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [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: 12/21/2017] [Revised: 03/01/2018] [Accepted: 03/20/2018] [Indexed: 01/29/2023] Open
Abstract
Synaptic activity in vivo can potentially alter the integration properties of neurons. Using recordings in awake mice, we targeted somatosensory layer 2/3 pyramidal neurons and compared neuronal properties with those from slices. Pyramidal cells in vivo had lower resistance and gain values, as well as broader spikes and increased spike frequency adaptation compared to the same cells in slices. Increasing conductance in neurons using dynamic clamp to levels observed in vivo, however, did not lessen the differences between in vivo and slice conditions. Further, local application of tetrodotoxin (TTX) in vivo blocked synaptic-mediated membrane voltage fluctuations but had little impact on pyramidal cell membrane input resistance and time constant values. Differences in electrophysiological properties of layer 2/3 neurons in mouse somatosensory cortex, therefore, stem from intrinsic sources separate from synaptic-mediated membrane voltage fluctuations.
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Affiliation(s)
- Fernando R Fernandez
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts 02215
| | - Bahar Rahsepar
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts 02215
| | - John A White
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts 02215
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21
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Taheri M, Handy G, Borisyuk A, White JA. Diversity of Evoked Astrocyte Ca 2+ Dynamics Quantified through Experimental Measurements and Mathematical Modeling. Front Syst Neurosci 2017; 11:79. [PMID: 29109680 PMCID: PMC5660282 DOI: 10.3389/fnsys.2017.00079] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [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: 08/01/2017] [Accepted: 10/04/2017] [Indexed: 01/06/2023] Open
Abstract
Astrocytes are a major cell type in the mammalian brain. They are not electrically excitable, but generate prominent Ca2+ signals related to a wide variety of critical functions. The mechanisms driving these Ca2+ events remain incompletely understood. In this study, we integrate Ca2+ imaging, quantitative data analysis, and mechanistic computational modeling to study the spatial and temporal heterogeneity of cortical astrocyte Ca2+ transients evoked by focal application of ATP in mouse brain slices. Based on experimental results, we tune a single-compartment mathematical model of IP3-dependent Ca2+ responses in astrocytes and use that model to study response heterogeneity. Using information from the experimental data and the underlying bifurcation structure of our mathematical model, we categorize all astrocyte Ca2+ responses into four general types based on their temporal characteristics: Single-Peak, Multi-Peak, Plateau, and Long-Lasting responses. We find that the distribution of experimentally-recorded response types depends on the location within an astrocyte, with somatic responses dominated by Single-Peak (SP) responses and large and small processes generating more Multi-Peak responses. On the other hand, response kinetics differ more between cells and trials than with location within a given astrocyte. We use the computational model to elucidate possible sources of Ca2+ response variability: (1) temporal dynamics of IP3, and (2) relative flux rates through Ca2+ channels and pumps. Our model also predicts the effects of blocking Ca2+ channels/pumps; for example, blocking store-operated Ca2+ (SOC) channels in the model eliminates Plateau and Long-Lasting responses (consistent with previous experimental observations). Finally, we propose that observed differences in response type distributions between astrocyte somas and processes can be attributed to systematic differences in IP3 rise durations and Ca2+ flux rates.
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Affiliation(s)
- Marsa Taheri
- Department of Bioengineering, University of Utah, Salt Lake City, UT, United States
| | - Gregory Handy
- Department of Mathematics, University of Utah, Salt Lake City, UT, United States
| | - Alla Borisyuk
- Department of Mathematics, University of Utah, Salt Lake City, UT, United States
| | - John A White
- Department of Biomedical Engineering, Boston University, Boston, MA, United States
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22
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Patel YA, George A, Dorval AD, White JA, Christini DJ, Butera RJ. Hard real-time closed-loop electrophysiology with the Real-Time eXperiment Interface (RTXI). PLoS Comput Biol 2017; 13:e1005430. [PMID: 28557998 PMCID: PMC5469488 DOI: 10.1371/journal.pcbi.1005430] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [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: 12/02/2016] [Revised: 06/13/2017] [Accepted: 02/10/2017] [Indexed: 01/24/2023] Open
Abstract
The ability to experimentally perturb biological systems has traditionally been limited to static pre-programmed or operator-controlled protocols. In contrast, real-time control allows dynamic probing of biological systems with perturbations that are computed on-the-fly during experimentation. Real-time control applications for biological research are available; however, these systems are costly and often restrict the flexibility and customization of experimental protocols. The Real-Time eXperiment Interface (RTXI) is an open source software platform for achieving hard real-time data acquisition and closed-loop control in biological experiments while retaining the flexibility needed for experimental settings. RTXI has enabled users to implement complex custom closed-loop protocols in single cell, cell network, animal, and human electrophysiology studies. RTXI is also used as a free and open source, customizable electrophysiology platform in open-loop studies requiring online data acquisition, processing, and visualization. RTXI is easy to install, can be used with an extensive range of external experimentation and data acquisition hardware, and includes standard modules for implementing common electrophysiology protocols.
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Affiliation(s)
- Yogi A. Patel
- Bioengineering Graduate Program, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, United States of America
| | - Ansel George
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, New York, United States of America
| | - Alan D. Dorval
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, United States of America
| | - John A. White
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
| | - David J. Christini
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, New York, United States of America
- * E-mail: (DJC); (RJB)
| | - Robert J. Butera
- Bioengineering Graduate Program, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- * E-mail: (DJC); (RJB)
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23
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Melonakos ED, White JA, Fernandez FR. Cover Image, Volume 26, Issue 12. Hippocampus 2016. [DOI: 10.1002/hipo.22677] [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: 11/05/2022]
Affiliation(s)
- Eric D. Melonakos
- Department of Bioengineering; University of Utah; Salt Lake City Utah
| | - John A. White
- Department of Bioengineering; University of Utah; Salt Lake City Utah
- Department of Biomedical Engineering; Boston University; Boston Massachusetts
| | - Fernando R. Fernandez
- Department of Bioengineering; University of Utah; Salt Lake City Utah
- Department of Biomedical Engineering; Boston University; Boston Massachusetts
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24
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Melonakos ED, White JA, Fernandez FR. Gain Modulation of Cholinergic Neurons in the Medial Septum-Diagonal Band of Broca Through Hyperpolarization. Hippocampus 2016; 26:1525-1541. [PMID: 27588894 DOI: 10.1002/hipo.22653] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [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: 06/28/2016] [Revised: 08/29/2016] [Accepted: 08/30/2016] [Indexed: 01/19/2023]
Abstract
Hippocampal network oscillations are important for learning and memory. Theta rhythms are involved in attention, navigation, and memory encoding, whereas sharp wave-ripple complexes are involved in memory consolidation. Cholinergic neurons in the medial septum-diagonal band of Broca (MS-DB) influence both types of hippocampal oscillations, promoting theta rhythms and suppressing sharp wave-ripples. They also receive frequency-dependent hyperpolarizing feedback from hippocamposeptal connections, potentially affecting their role as neuromodulators in the septohippocampal circuit. However, little is known about how the integration properties of cholinergic MS-DB neurons change with hyperpolarization. By potentially altering firing behavior in cholinergic neurons, hyperpolarizing feedback from the hippocampal neurons may, in turn, change hippocampal network activity. To study changes in membrane integration properties in cholinergic neurons in response to hyperpolarizing inputs, we used whole-cell patch-clamp recordings targeting genetically labeled, choline acetyltransferase-positive neurons in mouse brain slices. Hyperpolarization of cholinergic MS-DB neurons resulted in a long-lasting decrease in spike firing rate and input-output gain. Additionally, voltage-clamp measures implicated a slowly inactivating, 4-AP-insensitive, outward K+ conductance. Using a conductance-based model of cholinergic MS-DB neurons, we show that the ability of this conductance to modulate firing rate and gain depends on the expression of an experimentally verified shallow intrinsic spike frequency-voltage relationship. Together, these findings point to a means through which negative feedback from hippocampal neurons can influence the role of cholinergic MS-DB neurons. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Eric D Melonakos
- Department of Bioengineering, University of Utah, Salt Lake City, Utah
| | - John A White
- Department of Bioengineering, University of Utah, Salt Lake City, Utah.,Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Fernando R Fernandez
- Department of Bioengineering, University of Utah, Salt Lake City, Utah.,Department of Biomedical Engineering, Boston University, Boston, Massachusetts
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25
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Thurtle N, Dargan PI, Hunter LJ, Lovett C, White JA, Wood DM. A comparison of recreational drug use amongst sexual health clinic users in London with existing prevalence data. Int J STD AIDS 2016; 27:1309-1316. [DOI: 10.1177/0956462415616056] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Accepted: 10/07/2015] [Indexed: 11/17/2022]
Abstract
The objective was to give an overview of self-reported recreational drug use amongst attendees of sexual health clinics in London and compare this to existing datasets. Between December 2013 and March 2014, attendees of two sexual health clinics in London were surveyed. Data collected were: sexual history, smoking and alcohol and recreational drug use. Data were analysed using SPSS (version 21). A total of 1472 respondents were included; 778 (52.9%) men, 676 (45.9%) women and 3 (0.2%) transgender (15 [1.0%] did not answer). Mean age was 30.6 ± 9.0 years. A total of 339 (43.6%) men were men who have sex with men (MSM), and 18 (2.4%) women were women who have sex with women. Lifetime prevalence of use was: alcohol 94.1%; cannabis 48.5%; ‘poppers’ (volatile nitrites) 28.2%; cocaine 26.8% and 3,4-methylenedioxy-methamphetamine pills 23.2%. Our population had higher current popper, methamphetamine and mephedrone use than the Crime Survey of England and Wales but lower use of cannabis, poppers and Viagra than the European MSM Internet Survey. Global Drug Survey and Part of the Picture respondents’ use were higher than our population for all drugs. Drug use in this population had a different pattern to general population surveys and studies involving only MSM.
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Affiliation(s)
- Natalie Thurtle
- Clinical Toxicology Department, Guys and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, UK
| | - Paul I Dargan
- Clinical Toxicology Department, Guys and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, UK
- Clinical Toxicology Department, King’s College London, London, UK
| | - Laura J Hunter
- Clinical Toxicology Department, Guys and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, UK
| | - Caitlyn Lovett
- Clinical Toxicology Department, Guys and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, UK
| | - John A White
- Genitourinary Medicine, Guy’s and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, UK
| | - David M Wood
- Clinical Toxicology Department, Guys and St Thomas’ NHS Foundation Trust and King’s Health Partners, London, UK
- Clinical Toxicology Department, King’s College London, London, UK
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26
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Umpierre AD, Bennett IV, Nebeker LD, Newell TG, Tian BB, Thomson KE, White HS, White JA, Wilcox KS. Repeated low-dose kainate administration in C57BL/6J mice produces temporal lobe epilepsy pathology but infrequent spontaneous seizures. Exp Neurol 2016; 279:116-126. [PMID: 26896834 DOI: 10.1016/j.expneurol.2016.02.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [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: 11/20/2015] [Revised: 01/29/2016] [Accepted: 02/15/2016] [Indexed: 12/31/2022]
Abstract
More efficient or translationally relevant approaches are needed to model acquired temporal lobe epilepsy (TLE) in genetically tractable mice. The high costs associated with breeding and maintaining transgenic, knock-in, or knock-out lines place a high value on the efficiency of induction and animal survivability. Herein, we describe our approaches to model acquired epilepsy in C57BL/6J mice using repeated, low-dose kainate (KA) administration paradigms. Four paradigms (i.p.) were tested for their ability to induce status epilepticus (SE), temporal lobe pathology, and the development of epilepsy. All four paradigms reliably induce behavioral and/or electrographic SE without mortality over a 7d period. Two of the four paradigms investigated produce features indicative of TLE pathology, including hippocampal cell death, widespread astrogliosis, and astrocyte expression of mGluR5, a feature commonly reported in TLE models. Three of the investigated paradigms were able to produce aberrant electrographic features, such as interictal spiking in cortex. However, only one paradigm, previously published by others, produces spontaneous recurrent seizures over an eight week period. Presentation of spontaneous seizures is rare (N=2/14), with epilepsy preferentially developing in animals having a high number of seizures during SE. Overall, repeated, low-dose KA administration improves the efficiency and pathological relevance of a systemic KA insult, but does not produce a robust epilepsy phenotype under the experimental paradigms described herein.
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Affiliation(s)
- Anthony D Umpierre
- Interdepartmental Program in Neuroscience, University of Utah, 401 MREB, 20N. 1900E, Salt Lake City, UT 84132, United States.
| | - Isaiah V Bennett
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States.
| | - Lismore D Nebeker
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States.
| | - Thomas G Newell
- Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States; Dept. of Bioengineering, University of Utah, 36S. Wasatch Drive, Rm. 3100, Salt Lake City, UT 84112, United States.
| | - Bruce B Tian
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States.
| | - Kyle E Thomson
- Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States; Dept. of Bioengineering, University of Utah, 36S. Wasatch Drive, Rm. 3100, Salt Lake City, UT 84112, United States.
| | - H Steve White
- Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States; Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States; Department of Pharmacy, University of Washington, Box 357630, H375 Health Science Building, Seattle, WA 98195, United States.
| | - John A White
- Dept. of Biomedical Engineering, Boston University, 44 Cummington Mall, Rm. 403, Boston, MA 02215, United States.
| | - Karen S Wilcox
- Interdepartmental Program in Neuroscience, University of Utah, 401 MREB, 20N. 1900E, Salt Lake City, UT 84132, United States; Dept. of Pharmacology & Toxicology, University of Utah, College of Pharmacy, 30N. 1900E, Salt Lake City, UT 84112, United States; Anticonvulsant Drug Development Program, University of Utah, 417 Wakara Way, Suite 3211, Salt Lake City, UT 84108, United States.
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27
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Patel RR, White JA, Menon-Johansson AS, Sadiq ST, Ross JD. 2nd BASHH Oxford Diagnostics Course, November 2015. Int J STD AIDS 2016; 27:956462416628782. [PMID: 26787639 DOI: 10.1177/0956462416628782] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The second British Association for Sexual Health and HIV Oxford Diagnostics Course of 2015 focussed on recent challenges and emerging concepts within diagnostics and service design. In response to increasing sexually transmitted infection rates and subsequent demand on UK sexual health services, multiple approaches to improving patient flow and reducing waiting times were presented. The value of novel remote sexually transmitted infection testing was explored, with a description of the patient journey, emerging demographics and rates of testing uptake for the UK's leading National Health Service provider. A cost-benefit evaluation was made for the use of nucleic acid amplification tests versus traditional microscopy and culture for detecting Trichomonas vaginalis, with practical consideration of application to higher risk groups. Two speakers stressed the importance of vigilance against growing antimicrobial resistance. The significance of testing for genotypic markers for antimicrobial resistance, and the emergence of point-of-care tests for resistance were also presented. The meeting closed with a first-hand account of tendering, and practical advice on rebuilding professional relationships and services after a competitive process.
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Affiliation(s)
- R R Patel
- 1 Walsall Healthcare NHS Trust, Walsall, UK
| | - J A White
- 2 Guy's and St Thomas' NHS Foundation Trust, London, UK
| | | | - S T Sadiq
- 4 St. George's, University of London, London, UK
| | - J D Ross
- 5 University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
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28
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Krauer F, Oakley-Mudge S, Brook MG, White JA, Low N, Lee HH. P08.22 How high is high risk? sexual behaviour and chlamydia infections in women attending genitourinary medicine clinics. Br J Vener Dis 2015. [DOI: 10.1136/sextrans-2015-052270.368] [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: 11/03/2022]
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29
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Abstract
Temporal lobe epilepsy (TLE) is a devastating seizure disorder that is often caused by status epilepticus (SE). Temporal lobe epilepsy can be very difficult to control with currently available antiseizure drugs, and there are currently no disease-modifying therapies that can prevent the development of TLE in those patients who are at risk. While the functional changes that occur in neurons following SE and leading to TLE have been well studied, only recently has research attention turned to the role in epileptogenesis of astrocytes, the other major cell type of the brain. Given that epilepsy is a neural circuit disorder, innovative ways to evaluate the contributions that both neurons and astrocytes make to aberrant circuit activity will be critical for the understanding of the emergent network properties that result in seizures. Recently described approaches using genetically encoded calcium-indicating proteins can be used to image dynamic calcium transients, a marker of activity in both neurons and glial cells. It is anticipated that this work will lead to novel insights into the process of epileptogenesis at the network level and may identify disease-modifying therapeutic targets that have been missed because of a largely neurocentric view of seizure generation following SE. This article is part of a Special Issue entitled "Status Epilepticus".
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Affiliation(s)
- Karen S. Wilcox
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, USA,Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA,Corresponding author at: Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT 84108, USA. Tel.: +1 801 581 4081. (K.S. Wilcox)
| | - James M. Gee
- Department of Bioengineering, University of Utah, Salt Lake City, UT, USA
| | - Meredith B. Gibbons
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA
| | - Petr Tvrdik
- Department of Human Genetics, University of Utah, Salt Lake City, UT, USA
| | - John A. White
- Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA,Department of Bioengineering, University of Utah, Salt Lake City, UT, USA
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30
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White JA, Santos MJ, Rodríguez-Valverde MA, Velasco S. Numerical study of the most stable contact angle of drops on tilted surfaces. Langmuir 2015; 31:5326-5332. [PMID: 25909691 DOI: 10.1021/acs.langmuir.5b00834] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present results for the most stable contact angle using a numerical implementation of the tilting plate method of Montes et al. (Montes Ruiz-Cabello, F. J.; Rodriguez-Valverde, M. A.; Cabrerizo-Vilchez, M. Soft Matter 2011, 7, 10457-10461). Comparison with the experimental results is made, obtaining a good agreement in most situations. In addition, the evolution of the contact angles of a tilted drop with a fixed circular line is analyzed. This analysis allows one to theoretically predict the most stable contact angle for tilted drops.
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Affiliation(s)
- J A White
- †Department of Applied Physics, University of Salamanca, 37008 Salamanca, Spain
| | - M J Santos
- †Department of Applied Physics, University of Salamanca, 37008 Salamanca, Spain
| | - M A Rodríguez-Valverde
- ‡Biocolloid and Fluid Physics Group, Department of Applied Physics, University of Granada, Campus de Fuentenueva, E-18071 Granada, Spain
| | - S Velasco
- †Department of Applied Physics, University of Salamanca, 37008 Salamanca, Spain
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31
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Fernandez FR, Malerba P, White JA. Non-linear Membrane Properties in Entorhinal Cortical Stellate Cells Reduce Modulation of Input-Output Responses by Voltage Fluctuations. PLoS Comput Biol 2015; 11:e1004188. [PMID: 25909971 PMCID: PMC4409312 DOI: 10.1371/journal.pcbi.1004188] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [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: 06/26/2014] [Accepted: 02/10/2015] [Indexed: 11/19/2022] Open
Abstract
The presence of voltage fluctuations arising from synaptic activity is a critical component in models of gain control, neuronal output gating, and spike rate coding. The degree to which individual neuronal input-output functions are modulated by voltage fluctuations, however, is not well established across different cortical areas. Additionally, the extent and mechanisms of input-output modulation through fluctuations have been explored largely in simplified models of spike generation, and with limited consideration for the role of non-linear and voltage-dependent membrane properties. To address these issues, we studied fluctuation-based modulation of input-output responses in medial entorhinal cortical (MEC) stellate cells of rats, which express strong sub-threshold non-linear membrane properties. Using in vitro recordings, dynamic clamp and modeling, we show that the modulation of input-output responses by random voltage fluctuations in stellate cells is significantly limited. In stellate cells, a voltage-dependent increase in membrane resistance at sub-threshold voltages mediated by Na+ conductance activation limits the ability of fluctuations to elicit spikes. Similarly, in exponential leaky integrate-and-fire models using a shallow voltage-dependence for the exponential term that matches stellate cell membrane properties, a low degree of fluctuation-based modulation of input-output responses can be attained. These results demonstrate that fluctuation-based modulation of input-output responses is not a universal feature of neurons and can be significantly limited by subthreshold voltage-gated conductances. The membrane voltage of neurons in vivo is dominated by noisy “background” fluctuations generated by network-based synaptic activity from nearby cells. It has been speculated that membrane voltage fluctuations in neurons play an important role in scaling the relationship between input amplitude and spike rate response. For this to be true, neuronal spike input-output behavior must be sensitive to physiological membrane voltage fluctuations. Using a combination of single cell recordings and modeling, we investigated the mechanisms through which voltage fluctuations modulate neuronal input-output responses. We find that neurons that express an increase in membrane input resistance with depolarization show low levels of noise-mediated modulation of input-output responses due, in part, to voltage trajectories that suppress the likelihood of generating a spike in response to random current input fluctuations. Hence, non-linear membrane properties arising from certain types of voltage-gated conductances limit noise-based modulation of neuronal input-output responses.
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Affiliation(s)
- Fernando R. Fernandez
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, United States of America
- * E-mail:
| | - Paola Malerba
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, United States of America
| | - John A. White
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, United States of America
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Curry MM, Paliulis LV, Welch KD, Harwood JD, White JA. Multiple endosymbiont infections and reproductive manipulations in a linyphiid spider population. Heredity (Edinb) 2015; 115:146-52. [PMID: 25899011 DOI: 10.1038/hdy.2015.2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 12/06/2014] [Accepted: 12/19/2014] [Indexed: 12/17/2022] Open
Abstract
In many arthropods, maternally inherited endosymbiotic bacteria can increase infection frequency by manipulating host reproduction. Multiple infections of different bacteria in a single host population are common, yet few studies have documented concurrent endosymbiont phenotypes or explored their potential interactions. We hypothesized that spiders might be a particularly useful taxon for investigating endosymbiont interactions, because they are host to a plethora of endosymbiotic bacteria and frequently exhibit multiple infections. We established two matrilines from the same population of the linyphiid spider Mermessus fradeorum and then used antibiotic curing and controlled mating assays to demonstrate that each matriline was subject to a distinct endosymbiotic reproductive manipulation. One matriline was co-infected with Rickettsia and Wolbachia and produced offspring with a radical female bias. Antibiotic treatment eliminated both endosymbionts and restored an even sex ratio to subsequent generations. Chromosomal and fecundity observations suggest a feminization mechanism. In the other matriline, a separate factorial mating assay of cured and infected spiders demonstrated strong cytoplasmic incompatibility (CI) induced by a different strain of Wolbachia. However, males with this Wolbachia induced only mild CI when mated with the Rickettsia-Wolbachia females. In a subsequent survey of a field population of M. fradeorum, we detected these same three endosymbionts infecting 55% of the spiders in almost all possible combinations, with nearly half of the infected spiders exhibiting multiple infection. Our results suggest that a dynamic network of endosymbionts may interact both within multiply infected hosts and within a population subject to multiple strong reproductive manipulations.
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Affiliation(s)
- M M Curry
- Department of Entomology, University of Kentucky, Lexington, KY, USA
| | - L V Paliulis
- Department of Biology, Bucknell University, Lewisburg, PA, USA
| | - K D Welch
- Department of Entomology, University of Kentucky, Lexington, KY, USA
| | - J D Harwood
- Department of Entomology, University of Kentucky, Lexington, KY, USA
| | - J A White
- Department of Entomology, University of Kentucky, Lexington, KY, USA
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Gee JM, Gibbons MB, Taheri M, Palumbos S, Morris SC, Smeal RM, Flynn KF, Economo MN, Cizek CG, Capecchi MR, Tvrdik P, Wilcox KS, White JA. Imaging activity in astrocytes and neurons with genetically encoded calcium indicators following in utero electroporation. Front Mol Neurosci 2015; 8:10. [PMID: 25926768 PMCID: PMC4397926 DOI: 10.3389/fnmol.2015.00010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [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: 02/22/2015] [Accepted: 03/23/2015] [Indexed: 11/13/2022] Open
Abstract
Complex interactions between networks of astrocytes and neurons are beginning to be appreciated, but remain poorly understood. Transgenic mice expressing fluorescent protein reporters of cellular activity, such as the GCaMP family of genetically encoded calcium indicators (GECIs), have been used to explore network behavior. However, in some cases, it may be desirable to use long-established rat models that closely mimic particular aspects of human conditions such as Parkinson's disease and the development of epilepsy following status epilepticus. Methods for expressing reporter proteins in the rat brain are relatively limited. Transgenic rat technologies exist but are fairly immature. Viral-mediated expression is robust but unstable, requires invasive injections, and only works well for fairly small genes (<5 kb). In utero electroporation (IUE) offers a valuable alternative. IUE is a proven method for transfecting populations of astrocytes and neurons in the rat brain without the strict limitations on transgene size. We built a toolset of IUE plasmids carrying GCaMP variants 3, 6s, or 6f driven by CAG and targeted to the cytosol or the plasma membrane. Because low baseline fluorescence of GCaMP can hinder identification of transfected cells, we included the option of co-expressing a cytosolic tdTomato protein. A binary system consisting of a plasmid carrying a piggyBac inverted terminal repeat (ITR)-flanked CAG-GCaMP-IRES-tdTomato cassette and a separate plasmid encoding for expression of piggyBac transposase was employed to stably express GCaMP and tdTomato. The plasmids were co-electroporated on embryonic days 13.5-14.5 and astrocytic and neuronal activity was subsequently imaged in acute or cultured brain slices prepared from the cortex or hippocampus. Large spontaneous transients were detected in slices obtained from rats of varying ages up to 127 days. In this report, we demonstrate the utility of this toolset for interrogating astrocytic and neuronal activity in the rat brain.
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Affiliation(s)
- J Michael Gee
- Neuronal Dynamics Laboratory, Department of Bioengineering, University of Utah Salt Lake City, UT, USA ; MD-PhD Program, University of Utah Salt Lake City, UT, USA
| | - Meredith B Gibbons
- Glial-Neuronal Interactions in Epilepsy Laboratory, Department of Pharmacology and Toxicology, University of Utah Salt Lake City, UT, USA ; Interdepartmental Program in Neuroscience, University of Utah Salt Lake City, UT, USA
| | - Marsa Taheri
- Neuronal Dynamics Laboratory, Department of Bioengineering, University of Utah Salt Lake City, UT, USA
| | - Sierra Palumbos
- Mario Capecchi Laboratory, Department of Human Genetics, University of Utah Salt Lake City, UT, USA
| | - S Craig Morris
- Neuronal Dynamics Laboratory, Department of Bioengineering, University of Utah Salt Lake City, UT, USA ; Mario Capecchi Laboratory, Department of Human Genetics, University of Utah Salt Lake City, UT, USA
| | - Roy M Smeal
- Glial-Neuronal Interactions in Epilepsy Laboratory, Department of Pharmacology and Toxicology, University of Utah Salt Lake City, UT, USA
| | - Katherine F Flynn
- Glial-Neuronal Interactions in Epilepsy Laboratory, Department of Pharmacology and Toxicology, University of Utah Salt Lake City, UT, USA
| | - Michael N Economo
- Neuronal Dynamics Laboratory, Department of Bioengineering, University of Utah Salt Lake City, UT, USA
| | - Christian G Cizek
- Neuronal Dynamics Laboratory, Department of Bioengineering, University of Utah Salt Lake City, UT, USA ; Mario Capecchi Laboratory, Department of Human Genetics, University of Utah Salt Lake City, UT, USA
| | - Mario R Capecchi
- Mario Capecchi Laboratory, Department of Human Genetics, University of Utah Salt Lake City, UT, USA ; Department of Human Genetics, Howard Hughes Medical Institute, University of Utah Salt Lake City, UT, USA
| | - Petr Tvrdik
- Mario Capecchi Laboratory, Department of Human Genetics, University of Utah Salt Lake City, UT, USA
| | - Karen S Wilcox
- Glial-Neuronal Interactions in Epilepsy Laboratory, Department of Pharmacology and Toxicology, University of Utah Salt Lake City, UT, USA
| | - John A White
- Neuronal Dynamics Laboratory, Department of Bioengineering, University of Utah Salt Lake City, UT, USA
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Cooper GL, White JA, D'Elia JA, DeGirolami PC, Arkin C, Kaldany A, Platt R. Lack of Utility of Routine Screening Tests for Early Detection of Peritonitis in Patients Requiring Intermittent Peritoneal Dialysis. ACTA ACUST UNITED AC 2015; 5:321-5. [PMID: 6564084 DOI: 10.1017/s0195941700060501] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
AbstractA prospective study was undertaken to examine the clinical presentation of peritonitis in patients maintained on intermittent peritoneal dialysis and to determine the value of qualitative and quantitative dialysate cultures, gram stain, neutrophil counts, and a semiquantitative leukocyte test strip for case detection. Seven cases of peritonitis developed among 30 patients who underwent 553 dialyses. In most cases, neutrophil counts, cultures, and leukocyte test strip determinations were done within 48 hours prior to the clinical onset of peritonitis and in all instances failed to provide clues for incipient infection. Peritonitis was associated with a dialysate neutrophil count of >500/mm3 and leukocyte test strips were highly sensitive and specific for the detection of this quantity of neutrophils. A total of 16 dialysate cultures was positive in asymptomatic patients who did not have peritonitis. None of these patients subsequently developed peritonitis with the same organism. Dialysate gram stains, cultures, neutrophil counts or leukocyte test strips did not provide an early diagnosis of peritonitis and their use in the absence of symptoms is therefore not recommended.
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Magnani C, Economo MN, White JA, Moore LE. Nonlinear properties of medial entorhinal cortex neurons reveal frequency selectivity during multi-sinusoidal stimulation. Front Cell Neurosci 2014; 8:239. [PMID: 25191226 PMCID: PMC4137241 DOI: 10.3389/fncel.2014.00239] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 07/29/2014] [Indexed: 11/21/2022] Open
Abstract
The neurons in layer II of the medial entorhinal cortex are part of the grid cell network involved in the representation of space. Many of these neurons are likely to be stellate cells with specific oscillatory and firing properties important for their function. A fundamental understanding of the nonlinear basis of these oscillatory properties is critical for the development of theories of grid cell firing. In order to evaluate the behavior of stellate neurons, measurements of their quadratic responses were used to estimate a second order Volterra kernel. This paper uses an operator theory, termed quadratic sinusoidal analysis (QSA), which quantitatively determines that the quadratic response accounts for a major part of the nonlinearity observed at membrane potential levels characteristic of normal synaptic events. Practically, neurons were probed with multi-sinusoidal stimulations to determine a Hermitian operator that captures the quadratic function in the frequency domain. We have shown that the frequency content of the stimulation plays an important role in the characteristics of the nonlinear response, which can distort the linear response as well. Stimulations with enhanced low frequency amplitudes evoked a different nonlinear response than broadband profiles. The nonlinear analysis was also applied to spike frequencies and it was shown that the nonlinear response of subthreshold membrane potential at resonance frequencies near the threshold is similar to the nonlinear response of spike trains.
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Affiliation(s)
| | - Michael N Economo
- Department of Bioengineering, Brain Institute, University of Utah Salt Lake City, UT, USA
| | - John A White
- Department of Bioengineering, Brain Institute, University of Utah Salt Lake City, UT, USA
| | - Lee E Moore
- CNRS UMR 8257, Université Paris Descartes Paris, France
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Gee JM, Smith NA, Fernandez FR, Economo MN, Brunert D, Rothermel M, Morris SC, Talbot A, Palumbos S, Ichida JM, Shepherd JD, West PJ, Wachowiak M, Capecchi MR, Wilcox KS, White JA, Tvrdik P. Imaging activity in neurons and glia with a Polr2a-based and cre-dependent GCaMP5G-IRES-tdTomato reporter mouse. Neuron 2014; 83:1058-72. [PMID: 25155958 DOI: 10.1016/j.neuron.2014.07.024] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2014] [Indexed: 11/27/2022]
Abstract
UNLABELLED New strategies for introducing genetically encoded activity indicators into animal models facilitate the investigation of nervous system function. We have developed the PC::G5-tdT mouse line that expresses the GCaMP5G calcium indicator in a Cre-dependent fashion. Instead of targeting the ROSA26 locus, we inserted the reporter cassette nearby the ubiquitously expressed Polr2a gene without disrupting locus integrity. The indicator was tagged with IRES-tdTomato to aid detection of positive cells. This reporter system is effective in a wide range of developmental and cellular contexts. We recorded spontaneous cortical calcium waves in intact awake newborns and evaluated concentration-dependent responses to odorants in the adult olfactory bulb. Moreover, PC::G5-tdT effectively reports intracellular calcium dynamics in somas and fine processes of astrocytes and microglial cells. Through electrophysiological and behavioral analyses, we determined that GCaMP5G expression had no major impact on nervous system performance. PC::G5-tdT will be instrumental for a variety of brain mapping experiments. VIDEO ABSTRACT
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Affiliation(s)
- J Michael Gee
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112; Brain Institute, University of Utah, Salt Lake City, UT 84112; MD-PhD Program, University of Utah, Salt Lake City, UT 84112
| | - Nathan A Smith
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112; Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT 84112; Brain Institute, University of Utah, Salt Lake City, UT 84112
| | - Fernando R Fernandez
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112; Brain Institute, University of Utah, Salt Lake City, UT 84112
| | - Michael N Economo
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112; Brain Institute, University of Utah, Salt Lake City, UT 84112
| | - Daniela Brunert
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112; Brain Institute, University of Utah, Salt Lake City, UT 84112
| | - Markus Rothermel
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112; Brain Institute, University of Utah, Salt Lake City, UT 84112
| | - S Craig Morris
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112
| | - Amy Talbot
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112
| | - Sierra Palumbos
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112
| | - Jennifer M Ichida
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112
| | - Jason D Shepherd
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112
| | - Peter J West
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT 84112
| | - Matt Wachowiak
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112; Brain Institute, University of Utah, Salt Lake City, UT 84112
| | - Mario R Capecchi
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112; Howard Hughes Medical Institute, University of Utah, Salt Lake City, UT 84112
| | - Karen S Wilcox
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT 84112
| | - John A White
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112; Brain Institute, University of Utah, Salt Lake City, UT 84112.
| | - Petr Tvrdik
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112.
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Economo MN, Martínez JJ, White JA. Membrane potential-dependent integration of synaptic inputs in entorhinal stellate neurons. Hippocampus 2014; 24:1493-505. [PMID: 25044927 DOI: 10.1002/hipo.22329] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/10/2014] [Indexed: 11/06/2022]
Abstract
Stellate cells (SCs) of the medial entorhinal cortex exhibit robust spontaneous membrane-potential oscillations (MPOs) in the theta (4-12 Hz) frequency band as well as theta-frequency resonance in their membrane impedance spectra. Past experimental and modeling work suggests that these features may contribute to the phase-locking of SCs to the entorhinal theta rhythm and may be important for forming the hexagonally tiled grid cell place fields exhibited by these neurons in vivo. Among the major biophysical mechanisms contributing to MPOs is a population of persistent (non-inactivating or slowly inactivating) sodium channels. The resulting persistent sodium conductance (GNaP ) gives rise to an apparent increase in input resistance as the cell approaches threshold. In this study, we used dynamic clamp to test the hypothesis that this increased input resistance gives rise to voltage-dependent, and thus MPO phase-dependent, changes in the amplitude of excitatory and inhibitory post-synaptic potential (PSP) amplitudes. We find that PSP amplitude depends on membrane potential, exhibiting a 5-10% increase in amplitude per mV depolarization. The effect is larger than-and sums quasi-linearly with-the effect of the synaptic driving force, V - Esyn . Given that input-driven MPOs 10 mV in amplitude are commonly observed in MEC stellate cells in vivo, this voltage- and phase-dependent synaptic gain is large enough to modulate PSP amplitude by over 50% during theta-frequency MPOs. Phase-dependent synaptic gain may therefore impact the phase locking and phase precession of grid cells in vivo to ongoing network oscillations. © 2014 Wiley Periodicals, Inc.
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Affiliation(s)
- Michael N Economo
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts; Department of Bioengineering, Brain Institute, University of Utah, Salt Lake City, Utah
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Parker H, Ross JDC, White JA, Wilson JD. How important is confidentiality in sexual health clinics? A survey of patients across 51 clinics in England. Sex Transm Infect 2014; 90:354-5. [PMID: 25028709 DOI: 10.1136/sextrans-2013-051369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Helen Parker
- Department of Genitourinary Medicine, Centre for Sexual Health, Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Jonathan D C Ross
- Whittall Street Clinic, Birmingham University Hospital Foundation Trust, Birmingham, UK
| | - John A White
- Genitourinary Medicine, Lloyd Clinic, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Janet D Wilson
- Department of Genitourinary Medicine, Centre for Sexual Health, Leeds Teaching Hospitals NHS Trust, Leeds, UK
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Abstract
Patients with vulval aphthae, also termed Lipschütz ulcers, often present to genitourinary medicine clinics. Typically, these ulcers present as acute, painful, vulval ulcers in young women and adolescents. The aetiology is unknown, and often these ulcers are accompanied by flu-like symptoms. Previous case reports have linked such lesions to acute viral infections such as Epstein-Barr virus, cytomegalovirus and influenza A. We report the first case of influenza B virus and adenovirus infections associated with this presentation.
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Affiliation(s)
- G Haidari
- Genitourinary Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - E MacMahon
- Virology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - C Y W Tong
- Virology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - J A White
- Genitourinary Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UK
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Abstract
For over 60 years, real-time control has been an important technique in the study of excitable cells. Two such control-based technologies are reviewed here. First, voltage-clamp methods revolutionized the study of excitable cells. In this family of techniques, membrane potential is controlled, allowing one to parameterize a powerful class of models that describe the voltage-current relationship of cell membranes simply, flexibly, and accurately. Second, dynamic-clamp methods allow the addition of new, "virtual" membrane mechanisms to living cells. Dynamic clamp allows researchers unprecedented ways of testing computationally based hypotheses in biological preparations. The review ends with predictions of how control-based technologies will be improved and adapted for new uses in the near future.
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Haidari G, Perry MEO, White JA. Are we seeing a true rise inNeisseria gonorrhoeaeandChlamydia trachomatisin men who have sex with men in the UK? Sex Transm Infect 2014; 90:308. [DOI: 10.1136/sextrans-2014-051532] [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: 11/03/2022] Open
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Macdonald N, Sullivan AK, French P, White JA, Dean G, Smith A, Winter AJ, Alexander S, Ison C, Ward H. Risk factors for rectal lymphogranuloma venereum in gay men: results of a multicentre case-control study in the U.K. Sex Transm Infect 2014; 90:262-8. [PMID: 24493859 PMCID: PMC4033107 DOI: 10.1136/sextrans-2013-051404] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [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] [Indexed: 12/14/2022] Open
Abstract
Objective To identify risk factors for rectal lymphogranuloma venereum (rLGV) in men who have sex with men (MSM). Design A case-control study at 6 UK hospitals compared MSM with rLGV (cases) with rLGV-negative controls: MSM without potential rLGV symptoms (CGa) and separately, MSM with such symptoms (CGs). Methods Between 2008 and 2010, there were 90 rLGV cases, 74 CGa and 69 CGs recruited. Lifestyles and sexual behaviours in the previous 3 months were reported using internet-based computer-assisted self-interviews. Logistic regression was used to investigate factors associated with rLGV. Results Cases were significantly more likely to be HIV-positive (89%) compared with CGa (46%) and CGs (64%). Independent behavioural risks for rLGV were: unprotected receptive anal intercourse (adjusted OR (AOR)10.7, 95% CI 3.5 to 32.8), fisting another (AOR=6.7, CI 1.8 to 25.3), sex under the influence of gamma-hydroxybutyrate (AOR=3.1, CI 1.3 to 7.4) and anonymous sexual contacts (AOR=2.7, CI 1.2 to 6.3), compared with CGa; unprotected insertive anal intercourse (AOR=4.7, CI 2.0 to 10.9) and rectal douching (AOR=2.9 CI 1.3 to 6.6), compared with CGs. An incubation period from exposure to symptoms of 30 days was indicated. Conclusions Unprotected receptive anal intercourse is a key risk factor for rectal LGV with the likelihood that rectal-to-rectal transmission is facilitated where insertive anal sex also occurs. The association between HIV and rLGV appears linked to HIV-positive men seeking unprotected sex with others with the same HIV status, sexual and drug interests. Such men should be targeted for frequent STI screening and interventions to minimise associated risks.
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Affiliation(s)
- N Macdonald
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
| | - A K Sullivan
- Chelsea and Westminster NHS Foundation Trust, London, UK
| | - P French
- Mortimer Market Centre, Central and North West London NHS Foundation Trust, London, UK
| | - J A White
- Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - G Dean
- Brighton & Sussex University Hospitals NHS Trust, Brighton, UK
| | - A Smith
- Jefferiss Wing Centre for Sexual Health, Imperial College Healthcare NHS Trust, London, UK
| | - A J Winter
- Sandyford Sexual Health Services, Glasgow, UK
| | - S Alexander
- Sexually Transmitted Bacterial Reference Unit, Public Health England, London, UK
| | - C Ison
- Sexually Transmitted Bacterial Reference Unit, Public Health England, London, UK
| | - H Ward
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London, UK
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Hunter LJ, Dargan PI, Benzie A, White JA, Wood DM. Recreational drug use in men who have sex with men (MSM) attending UK sexual health services is significantly higher than in non-MSM. Postgrad Med J 2014; 90:133-8. [PMID: 24390619 DOI: 10.1136/postgradmedj-2012-131428] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION The aim of this study was to investigate the pattern of recreational drug use in patients attending a genitourinary medicine clinic, and to determine whether drug use was greater among men who have sex with men (MSM) patients, when compared to non-MSM male patients. METHODS A questionnaire was given to all patients attending the genitourinary medicine clinics at two inner city teaching hospitals over 3 months (July to September 2011). The questionnaire was self-completed by patients while waiting to be seen by a clinician. Data were collected on age, gender, gender of sexual partner(s), and previous/current recreational drug use (type/frequency of drugs used). Only data from male respondents have been analysed in this paper. RESULTS 1328 questionnaires were completed. Of the male respondents (n=729), 475 (65.2%) were identified as non-MSM and 254 (34.8%) were identified as MSM. The mean ± SD age of male respondents was 31 ± 9 years years. Lifetime and last month use of mephedrone, ketamine, volatile nitrites ('poppers'), sildenafil (Viagra), GHB, and GBL were all significantly higher in the MSM group compared to the non-MSM group. Lifetime use of cocaine powder, MDMA, amphetamine, and methamphetamine were also significantly higher in the MSM group; however, there was no significant difference in last month use of these drugs between MSM and non-MSM groups. CONCLUSIONS Both lifetime and last month use of most recreational drugs was more common in MSM, when compared to non-MSM males. Sexual health clinics may provide an opportunistic encounter to identify patterns of recreational drug use, explore motivations for use, and implement strategies to reduce harms related to drug use. This will require a multidisciplinary approach to address the psychosocial aspects of drug taking behaviours, in combination with healthcare professionals experienced in the management of recreational drug use.
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Affiliation(s)
- L J Hunter
- Emergency Medicine and Clinical Toxicology, Guy's and St Thomas' NHS Foundation Trust and King's Health Partners, , London, UK
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de Vries HJC, Zingoni A, White JA, Ross JDC, Kreuter A. 2013 European Guideline on the management of proctitis, proctocolitis and enteritis caused by sexually transmissible pathogens. Int J STD AIDS 2013; 25:465-74. [PMID: 24352129 DOI: 10.1177/0956462413516100] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [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: 08/30/2013] [Accepted: 10/21/2013] [Indexed: 11/17/2022]
Abstract
Proctitis is defined as an inflammatory syndrome of the distal 10-12 cm of the anal canal, also called the rectum. Infectious proctitis can be sexually transmitted via genital-anal mucosal contact, but some also via mutual masturbation.N. gonorrhoeae,C. trachomatis(including lymphogranuloma venereum), Herpes Simplex Virus andT. pallidumare the most common sexually transmitted anorectal pathogens. Shigellosis can be transferred via oral-anal contact and may lead to proctocolitis or enteritis. Although most studies on these infections have concentrated on men who have sex with men (MSM), a significant proportion of women have anal intercourse and therefore may also be at risk. A presumptive clinical diagnosis of proctitis can be made when there are symptoms and signs, and a definitive diagnosis when the results of laboratory tests are available. The symptoms of proctitis include anorectal itching, pain, cramps (tenesmus) and discharge in and around the anal canal. Asymptomatic proctitis occurs frequently and can only be detected by laboratory tests. The majority of rectal chlamydia and gonococcal infections are asymptomatic. Therefore when there is a history of receptive anal contact, exclusion of anorectal infections is generally indicated as part of standard screening for sexually transmitted infections (STIs). Condom use does not guarantee protection from bacterial and protozoan STIs, which are often spread without penile penetration.
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Affiliation(s)
- Henry J C de Vries
- STI outpatient clinic, Cluster Infectious Diseases, Health Service Amsterdam, Amsterdam, The Netherlands Department of Dermatology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands Centre for Infectious Diseases and Immunology Amsterdam (CINIMA), Amsterdam, The Netherlands Centre for Infectious Disease Control, National Institute of Public Health and the Environment, Bilthoven, The Netherlands
| | - Adele Zingoni
- Department of Biomedical Sciences and Human Oncology, Dermatologic Clinic, University of Turin, Turin, Italy
| | - John A White
- Department of Genitourinary Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Jonathan D C Ross
- Sexual Health Clinic - University Hospitals Birmingham NHS Foundation Trust, Whittall Street Clinic, Birmingham, UK
| | - Alexander Kreuter
- Department of Dermatology, Venereology, and Allergology, HELIOS St. Elisabeth Hospital Oberhausen, Germany
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White JA, Rajchl M, Butler J, Sykes J, Blackwood K, Thompson RT, Prato FS, Wisenberg G. Influence of Microvascular Obstruction on Cellular Inflammation During Early Stages of Acute Myocardial Infarction: Evaluation Using Hybrid Pet-MRI Imaging. Can J Cardiol 2013. [DOI: 10.1016/j.cjca.2013.07.191] [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: 11/29/2022] Open
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Unemo M, Brooks B, Cole M, Ross JDC, White JA, Patel R. Does the ‘2012 IUSTI ECCG report on the diagnosis and management of Neisseria gonorrhoeae infections in Europe’ depict the situation in Europe? Int J STD AIDS 2013; 24:423-6. [DOI: 10.1177/0956462412473383] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Summary Gonorrhoea is a major public health concern globally. Of particular grave concern is that resistance to the third generation cephalosporins has been identified during recent years. This paper summarises and discusses the results of the ‘2012 IUSTI European Collaborative Clinical Group (ECCG) report on the diagnosis and management of Neisseria gonorrhoeae infections in Europe’. Although high quality care was reported in many settings, in several other countries the testing, diagnostics, antimicrobial treatment and follow-up of gonorrhoea patients need to be optimized. This, together with increased access to and use of antimicrobial susceptibility testing, is crucial in controlling the emergent spread of cephalosporin-resistant and multidrug-resistant gonorrhoea.
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Affiliation(s)
- M Unemo
- World Health Organization Collaborating Centre for Gonorrhoea and Other Sexually Transmitted Infections, Örebro University Hospital, Örebro, Sweden
| | - B Brooks
- Department of Genitourinary Medicine, Southampton Medical School, University of Southampton, Southampton
| | - M Cole
- Sexually Transmitted Bacteria Reference Laboratory, Health Protection Agency, Colindale, London
| | - J D C Ross
- Birmingham University Hospital, Birmingham
| | - J A White
- Guy's and St Thomas’ NHS Foundation Trust, London, UK
| | - R Patel
- Department of Genitourinary Medicine, Southampton Medical School, University of Southampton, Southampton
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Haidari G, Stockwell S, Elgalib A, Surah S, Tong WCY, Alexander S, White JA. P3.153 Clinical Features and Treatment Responses in 300 Pharyngeal Chlamydia TrachomatisInfections in MSM. Br J Vener Dis 2013. [DOI: 10.1136/sextrans-2013-051184.0611] [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: 11/03/2022]
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Perry MEO, Haidari G, White JA. P2.035 As Nucleic Acid Amplification Testing For Neisseria GonorrhoeaeIncreases is Culture Confirmation Decreasing?: Abstract P2.035 Table 1. Br J Vener Dis 2013. [DOI: 10.1136/sextrans-2013-051184.0300] [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: 11/04/2022]
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Haidari G, White JA. P2.132 Pharyngeal and Conjunctival Chlamydia TrachomatisInfections: Chicken or Egg? Br J Vener Dis 2013. [DOI: 10.1136/sextrans-2013-051184.0396] [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: 11/04/2022]
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Haidari G, Perry MEO, White JA. P3.121 Are We Seeing a True Rise in Neisseria Gonorrhoeaeand Chlamydia Trachomatisin England in Men Who Have Sex with Men?: Abstract P3.121 Table 1. Br J Vener Dis 2013. [DOI: 10.1136/sextrans-2013-051184.0580] [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: 11/04/2022]
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