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Diamantis I. Tsilimigras MD Rittal Mehta MPH Alfredo Guglielmi MD Francesca Ratti MD Hugo P. Marques MD Olivier Soubrane MD Vincent Lam MD George A. Poultsides MD Irinel Popescu MD Sorin Alexandrescu MD Guillaume Martel MD Tom Hugh MD Luca Aldrighetti MD Itaru Endo MD PhD Timothy M. Pawlik MD MPH PhD FACS FRACS 《Journal of surgical oncology》2020,122(5):955-963
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The hippocampal system contains neural populations that encode an animal's position and velocity as it navigates through space. Here, we show that such populations can embed two codes within their spike trains: a firing rate code ( R ) conveyed by within‐cell spike intervals, and a co‐firing rate code () conveyed by between‐cell spike intervals. These two codes behave as conjugates of one another, obeying an analog of the uncertainty principle from physics: information conveyed in R comes at the expense of information in , and vice versa. An exception to this trade‐off occurs when spike trains encode a pair of conjugate variables, such as position and velocity, which do not compete for capacity across R and . To illustrate this, we describe two biologically inspired methods for decoding R and , referred to as sigma and sigma‐chi decoding, respectively. Simulations of head direction and grid cells show that if firing rates are tuned for position (but not velocity), then position is recovered by sigma decoding, whereas velocity is recovered by sigma‐chi decoding. Conversely, simulations of oscillatory interference among theta‐modulated “speed cells” show that if co‐firing rates are tuned for position (but not velocity), then position is recovered by sigma‐chi decoding, whereas velocity is recovered by sigma decoding. Between these two extremes, information about both variables can be distributed across both channels, and partially recovered by both decoders. These results suggest that populations with different spatial and temporal tuning properties—such as speed versus grid cells—might not encode different information, but rather, distribute similar information about position and velocity in different ways across R and . Such conjugate coding of position and velocity may influence how hippocampal populations are interconnected to form functional circuits, and how biological neurons integrate their inputs to decode information from firing rates and spike correlations. 相似文献
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Madeleine E. Cunningham Gavin R. Meehan Sophie Robinson Denggao Yao Rhona McGonigal Hugh J. Willison 《Journal of the peripheral nervous system : JPNS》2020,25(2):143-151
In mouse models of acute motor axonal neuropathy, anti‐ganglioside antibodies (AGAbs) bind to motor axons, notably the distal nerve, and activate the complement cascade. While complement activation is well studied in this model, the role of inflammatory cells is unknown. Herein we aimed to investigate the contribution of phagocytic cells including macrophages, neutrophils and perisynaptic Schwann cells (pSCs) to distal nerve pathology. To observe this, we first created a subacute injury model of sufficient duration to allow inflammatory cell recruitment. Mice were injected intraperitoneally with an anti‐GD1b monoclonal antibody that binds strongly to mouse motor nerve axons. Subsequently, mice received normal human serum as a source of complement. Dosing was titrated to allow humane survival of mice over a period of 3 days, yet still induce the characteristic neurological impairment. Behaviour and pathology were assessed in vivo using whole‐body plethysmography and post‐sacrifice by immunofluorescence and flow cytometry. ex vivo nerve‐muscle preparations were used to investigate the acute phagocytic role of pSCs following distal nerve injury. Following complement activation at distal intramuscular nerve sites in the diaphragm macrophage localisation or numbers are not altered, nor do they shift to a pro‐ or anti‐inflammatory phenotype. Similarly, neutrophils are not significantly recruited. Instead, ex vivo nerve‐muscle preparations exposed to AGAb plus complement reveal that pSCs rapidly become phagocytic and engulf axonal debris. These data suggest that pSCs, rather than inflammatory cells, are the major cellular vehicle for axonal debris clearance following distal nerve injury, in contrast to larger nerve bundles where macrophage‐mediated clearance predominates. 相似文献
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Drug use,health and social outcomes of hard‐to‐treat heroin addicts receiving supervised injectable opiate treatment: secondary outcomes from the Randomized Injectable Opioid Treatment Trial (RIOTT) 下载免费PDF全文
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David M. Fleischer Scott Sicherer Matthew Greenhawt Dianne Campbell Edmond Chan Antonella Muraro Susanne Halken Yitzhak Katz Motohiro Ebisawa Lawrence Eichenfield Hugh Sampson Gideon Lack George Du Toit Graham Roberts Henry Bahnson Mary Feeney Jonathan Hourihane Jonathan Spergel Michael Young Amal As'aad Katrina Allen Susan Prescott Sandeep Kapur Hirohisa Saito Ioana Agache Cezmi A. Akdis Hasan Arshad Kirsten Beyer Anthony Dubois Philippe Eigenmann Monserrat Fernandez‐Rivas Kate Grimshaw Karin Hoffman‐Sommergruber Arne Host Susanne Lau Liam O'Mahony Clare Mills Nikolaus Papadopoulos Carina Venter Nancy Agmon‐Levin Aaron Kessel Richard Antaya Beth Drolet Lanny Rosenwasser 《Pediatric dermatology》2016,33(1):103-106
The purpose of this brief communication is to highlight emerging evidence regarding potential benefits of supporting early rather than delayed peanut introduction during the period of complementary food introduction in infants. This document should be considered as interim guidance based on consensus among the following organizations: American Academy of Allergy, Asthma, and Immunology, American Academy of Pediatrics, American College of Allergy, Asthma, and Immunology, Australasian Society of Clinical Immunology and Allergy, Canadian Society of Allergy and Clinical Immunology, European Academy of Allergy and Clinical Immunology, Israel Association of Allergy and Clinical Immunology, Japanese Society for Allergology, Society for Pediatric Dermatology, and World Allergy Organization. More formal guidelines regarding early‐life, complementary feeding practices and the risk of allergy development will follow in the next year from the National Institute of Allergy and Infectious Diseases—sponsored Working Group and the European Academy of Allergy and Clinical Immunology. 相似文献