Neuron-glial Interactions

Although lagging behind classical computational neuroscience, theoretical and computational approaches are beginning to emerge to characterize different aspects of neuron-glial interactions. This chapter aims to provide essential knowledge on neuron-glial interactions in the mammalian brain, leveraging on computational studies that focus on structure (anatomy) and function (physiology) of such interactions in the healthy brain. Although our understanding of the need of neuron-glial interactions in the brain is still at its infancy, being mostly based on predictions that await for experimental validation, simple general modeling arguments borrowed from control theory are introduced to support the importance of including such interactions in traditional neuron-based modeling paradigms.Junior Leader Fellowship Program by “la Caixa” Banking Foundation (LCF/BQ/LI18/11630006

A Neuron-Glial Perspective for Computational Neuroscience

International audienceThere is growing excitement around glial cells, as compelling evidence point to new, previously unimaginable roles for these cells in information processing of the brain, with the potential to affect behavior and higher cognitive functions. Among their many possible functions, glial cells could be involved in practically every aspect of the brain physiology in health and disease. As a result, many investigators in the field welcome the notion of a Neuron-Glial paradigm of brain function, as opposed to Ramon y Cayal's more classical neuronal doctrine which identifies neurons as the prominent, if not the only, cells capable of a signaling role in the brain. The demonstration of a brain-wide Neuron-Glial paradigm however remains elusive and so does the notion of what neuron-glial interactions could be functionally relevant for the brain computational tasks. In this perspective, we present a selection of arguments inspired by available experimental and modeling studies with the aim to provide a biophysical and conceptual platform to computational neuroscience no longer as a mere prerogative of neuronal signaling but rather as the outcome of a complex interaction between neurons and glial cells

Neuron-Glial Interactions

Although lagging behind classical computational neuroscience, theoretical and computational approaches are beginning to emerge to characterize different aspects of neuron-glial interactions. This chapter aims to provide essential knowledge on neuron-glial interactions in the mammalian brain, leveraging on computational studies that focus on structure (anatomy) and function (physiology) of such interactions in the healthy brain. Although our understanding of the need of neuron-glial interactions in the brain is still at its infancy, being mostly based on predictions that await for experimental validation, simple general modeling arguments borrowed from control theory are introduced to support the importance of including such interactions in traditional neuron-based modeling paradigms.Comment: 43 pages, 2 figures, 1 table. Accepted for publication in the "Encyclopedia of Computational Neuroscience," D. Jaeger and R. Jung eds., Springer-Verlag New York, 2020 (2nd edition

Echoanatomical patterns of the long saphenous vein in patients with primary varices and in healthy subjects

Objective: To evaluate the pathway of reflux in incompetent long saphenous veins (LSVs), paying particular attention to the role of longitudinal saphenous tributaries in the thigh (accessory saphenous veins, ASVs). Design: Prospective study in a group of patients with primary varices. Comparison with the anatomical patterns in a group of normal subjects. Setting: Private phlebology practice. Patients: Sixty-seven patients with primary varices (100 limbs) and 66 subjects without varices and with competent saphenous veins (120 limbs). Methods: Duplex ultrasound evaluation of the saphenous system in the thigh of patients and healthy subjects. The 'eye' ultrasonographic sign was used as the marker to distinguish the LSV from the longitudinal tributary veins of the thigh. Results: In 57% of limbs in patients with varices, reflux followed the saphenous vein, while in 43% the reflux spilled outside the LSV into an ASV (h or S types). When reflux followed the saphenous vein, no large calibre ASVs could be observed. In 30% of limbs in control subjects a parallel tributary vein with a similar calibre was found joining the LSV. Conclusion: Clinically visible varices in the thigh rarely comprise the LSV itself, but are usually dilated ASVs, the reflux stream passing from the proximal LSV into a more superficial ASV. The distal LSV running parallel beneath is often competent. In subjects with healthy LSVs, a large competent tributary vein is already present in the thigh in 30% of cases. This suggests that superficial deviation of reflux flow into an ASV in patients with varices may not arise from haemodynamically acquired changes, but could have a congenital origin. This could even be a predisposing factor in the development of varices