Search results for "C3"
showing 10 items of 1295 documents
Contrasting coping styles meet the wall: A dopamine driven dichotomy in behavior and cognition
2017
Individual variation in the ability to modify previously learned behaviour is an important dimension of trait correlations referred to as coping styles, behavioral syndromes or personality. These trait clusters have been shaped by natural selection, and underlying control mechanisms are often conserved throughout vertebrate evolution. In teleost fishes, behavioral flexibility and coping style have been studied in the high (HR) and low-responsive (LR) rainbow trout lines. Generally, proactive LR trout show a behaviour guided by previously learned routines, while HR trout show a more flexible behaviour relying on environmental cues. In mammals, routine dependent vs flexible behavior has been …
Non-Rapid Eye Movement Sleep Parasomnias and Migraine: A Role of Orexinergic Projections
2018
Introduction: Sleep and migraine share a common pathophysiological substrate, although the underlying mechanisms are unknown. The serotonergic and orexinergic systems are both involved in the regulation of sleep/wake cycle, and numerous studies show that both are involved in the migraine etiopathogenesis. These two systems are anatomically and functionally interconnected. Our hypothesis is that in migraine a dysfunction of orexinergic projections on the median raphe (MR) nuclei, interfering with serotonergic regulation, may cause Non-Rapid Eye Movement parasomnias, such as somnambulism. Hypothesis/theory: Acting on the serotonergic neurons of the raphe nuclei, the dysfunction of orexinergic…
Cellular Response to Spinal Cord Injury in Regenerative and Non-Regenerative Stages in Xenopus Laevis
2020
Abstract Background The efficient regenerative abilities at larvae stages followed by a non-regenerative response after metamorphosis in froglets makes Xenopus an ideal model organism to understand the cellular responses leading to spinal cord regeneration. Methods We compared the cellular response to spinal cord injury between the regenerative and non-regenerative stages of Xenopus laevis. For this analysis, we used electron microscopy, immunofluorescence and histological staining of the extracellular matrix. We generated two transgenic lines: i) the reporter line with the zebrafish GFAP regulatory regions driving the expression of EGFP, and ii) a cell specific inducible ablation line with…
Multiple steady states and the form of response functions to antigen in a model for the initiation of T cell activation
2017
The aim of this paper is to study the qualitative behaviour predicted by a mathematical model for the initial stage of T-cell activation. The state variables in the model are the concentrations of phosphorylation states of the T-cell receptor (TCR) complex and the phosphatase SHP-1 in the cell. It is shown that these quantities cannot approach zero and that the model possesses more than one positive steady state for certain values of the parameters. It can also exhibit damped oscillations. It is proved that the chemical concentration which represents the degree of activation of the cell, that of the maximally phosphorylated form of the TCR complex, is, in general, a non-monotone function of…
Hyperforin Potentiates Antidepressant-Like Activity of Lanicemine in Mice
2018
International audience; N-methyl-D-aspartate receptor (NMDAR) modulators induce rapid and sustained antidepressant like-activity in rodents through a molecular mechanism of action that involves the activation of Ca2+ dependent signaling pathways. Moreover, ketamine, a global NMDAR antagonist is a potent, novel, and atypical drug that has been successfully used to treat major depressive disorder (MDD). However, because ketamine evokes unwanted side effects, alternative strategies have been developed for the treatment of depression. The objective of the present study was to determine the antidepressant effects of either a single dose of hyperforin or lanicemine vs. their combined effects in m…
Retinal Thickness and Microvascular Pattern in Early Parkinson's Disease.
2020
A thinning of intraretinal layers has been previously described in Parkinson's disease (PD) patients compared to healthy controls (HCs). Few studies evaluated the possible correlation between retinal thickness and retinal microvascularization. Thus, here we assessed the thickness of retinal layers and microvascular pattern in early PD patients and HCs, using, respectively, spectral-domain optical coherence tomography (SD-OCT) and SD-OCT-angiography (SD-OCT-A), and more interestingly, we evaluated a possible correlation between retinal thickness and microvascular pattern. Patients fulfilling criteria for clinically established/clinically probable PD and HCs were enrolled. Exclusion criteria …
Cellular and Molecular Mechanisms of Fat Taste Perception
2021
During the last couples of years, a number of studies have increasingly accumulated on the gustatory perception of dietary fatty acids in rodent models and human beings in health and disease. There is still a debate to coin a specific term for the gustatory perception of dietary fatty acids either as the sixth basic taste quality or as an alimentary taste. Indeed, the psycho-physical cues of orosensory detection of dietary lipids are not as distinctly perceived as other taste qualities like sweet or bitter. The cellular and molecular pharmacological mechanisms, triggered by the binding of dietary long-chain fatty acids (LCFAs) to tongue taste bud lipid receptors like CD36 and GPR120, involv…
Primary Sensorimotor Cortex Drives the Common Cortical Network for Gamma Synchronization in Voluntary Hand Movements
2018
Background: Gamma synchronization (GS) may promote the processing between functionally related cortico-subcortical neural populations. Our aim was to identify the sources of GS and to analyze the direction of information flow in cerebral networks at the beginning of phasic movements, and during medium-strength isometric contraction of the hand. Methods: We measured 64-channel electroencephalography in 11 healthy volunteers (age: 25 ± 8 years; four females); surface electromyography detected the movements of the dominant hand. In Task 1, subjects kept a constant medium-strength contraction of the first dorsal interosseus muscle, and performed a superimposed repetitive voluntary self-paced br…
Anti-inflammatory and cognitive effects of interferon-β1a (IFNβ1a) in a rat model of Alzheimer’s disease
2018
Background: Aβ 1-42 peptide abnormal production is associated with the development and maintenance of neuroinflammation and oxidative stress in brains from Alzheimer disease (AD) patients. Suppression of neuroinflammation may then represent a suitable therapeutic target in AD. We evaluated the efficacy of IFNβ1a in attenuating cognitive impairment and inflammation in an animal model of AD. Methods: A rat model of AD was obtained by intra-hippocampal injection of Aβ 1-42 peptide (23 μg/2 μl). After 6 days, 3.6 μg of IFNβ1a was given subcutaneously (s.c.) for 12 days. Using the novel object recognition (NOR) test, we evaluated changes in cognitive function. Measurement of pro-inflammatory or …
Neurostimulation and Reach-to-Grasp Function Recovery Following Acquired Brain Injury: Insight From Pre-clinical Rodent Models and Human Applications.
2020
Reach-to-grasp is an evolutionarily conserved motor function that is adversely impacted following stroke and traumatic brain injury (TBI). Non-invasive brain stimulation (NIBS) methods, such as transcranial magnetic stimulation and transcranial direct current stimulation, are promising tools that could enhance functional recovery of reach-to-grasp post-brain injury. Though the rodent literature provides a causal understanding of post-injury recovery mechanisms, it has had a limited impact on NIBS protocols in human research. The high degree of homology in reach-to-grasp circuitry between humans and rodents further implies that the application of NIBS to brain injury could be better informed…