The pattern-reversal visual evoked response (VER) was recorded in 2 patients during transient monocular visual reduction. In both cases the VER was initially abolished. With recovery of vision there was gradual return of amplitude over a 3- to 8-minute period, while latencies remained unchanged from preattack values. These findings are discussed with regard to current understanding of the origins of the VER and relevant aspects of retinal electrophysiology.
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http://dx.doi.org/10.1136/bjo.66.6.382 | DOI Listing |
Med Phys
January 2025
OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.
Background: Previous studies have shown that in-beam magnetic resonance imaging (MRI) can be used to visualize a proton beam during the irradiation of liquid-filled phantoms. The beam energy- and current-dependent local image contrast observed in water was identified to be predominantly caused by beam-induced buoyant convection and associated flow effects. Besides this flow dependency, the MR signal change was found to be characterized by a change in the relaxation time of water, hinting at a radiochemical contribution, which was hypothesized to lie in oxygen depletion-evoked relaxation time lengthening.
View Article and Find Full Text PDFLife Metab
February 2025
New Cornerstone Science Laboratory, State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, National Biomedical Imaging Center, The Beijing Laboratory of Biomedical Imaging, Peking-Tsinghua Center for Life Sciences, School of Future Technology, Peking University, Beijing 100871, China.
Glucose-stimulated insulin release from pancreatic β-cells is critical for maintaining blood glucose homeostasis. An abrupt increase in blood glucose concentration evokes a rapid and transient rise in insulin secretion followed by a prolonged, slower phase. A diminished first phase is one of the earliest indicators of β-cell dysfunction in individuals predisposed to develop type 2 diabetes.
View Article and Find Full Text PDFNeurophotonics
January 2025
University of Illinois Chicago, Department of Biomedical Engineering, Chicago, Illinois, United States.
Significance: Stimulus-evoked intrinsic optical signal (IOS) changes in retinal photoreceptors are critical for functional optoretinography (ORG). Optical coherence tomography (OCT), with its depth-resolved imaging capability, has been actively explored for IOS imaging of retinal photoreceptors. However, recent OCT studies have reported conflicting results regarding light-induced changes in the photoreceptor outer segments (OSs), with both elongation and shrinkage being observed.
View Article and Find Full Text PDFBrain Behav Immun
January 2025
Department of Biology, Neuroendocrinology and Human Biology Unit, Institute for Animal Cell- and Systems Biology, Faculty of Mathematics, Informatics and Natural Sciences, Universität Hamburg, D-22085 Hamburg, Germany. Electronic address:
This study investigated the neural correlates of perceiving visual contagion cues characteristic of respiratory infections through functional magnetic resonance imaging (fMRI). Sixty-two participants (32f/ 30 m; ∼25 years on average) watched short videos depicting either contagious or non-contagious everyday situations, while their brain activation was continuously measured. We further measured the release of secretory immunoglobulin A (sIgA) in saliva to examine the first-line defensive response of the mucosal immune system.
View Article and Find Full Text PDFBiomed Phys Eng Express
January 2025
Children's Hospital of Eastern Switzerland, Claudiusstrasse 6, St.Gallen, 9006, SWITZERLAND.
Mapping the myomagnetic field of a straight and easily accessible muscle after electrical stimulation using triaxial optically pumped magnetometers (OPMs) to assess potential benefits for magnetomyography (MMG). Approach: Six triaxial OPMs were arranged in two rows with three sensors each along the abductor digiti minimi (ADM) muscle. The upper row of sensors was inclined by 45° with respect to the lower row and all sensors were aligned closely to the skin surface without direct contact.
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