Search results for "neuron"

New insight on the role of late indirect‐wave pathway underlying theta‐burst stimulation‐induced plasticity

2020

International audience

2019

AbstractDuring early postnatal life, speed up of signal propagation through many central and peripheral neurons has been associated with an increase in axon diameter or/and myelination. Especially in unmyelinated axons postnatal adjustments of axonal membrane conductances is potentially a third mechanism but solid evidence is lacking. Here, we show that axonal action potential (AP) conduction velocity in theDrosophilagiant fiber (GF) interneuron, which is required for fast long-distance signal conduction through the escape circuit, is increased by 80% during the first day of adult life. Genetic manipulations indicate that this postnatal increase in AP conduction velocity in the unmyelinated…

2013

Controlling the position of the nucleus is vital for a number of cellular processes from yeast to humans. In Drosophila nurse cells, nuclear positioning is crucial during dumping, when nurse cells contract and expel their contents into the oocyte. We provide evidence that in nurse cells, continuous filopodia-like actin cables, growing from the plasma membrane and extending to the nucleus, achieve nuclear positioning. These actin cables move nuclei away from ring canals. When nurse cells contract, actin cables associate laterally with the nuclei, in some cases inducing nuclear turning so that actin cables become partially wound around the nuclei. Our data suggest that a perinuclear actin mes…

Robust and sensitive GFP-based cGMP sensor for real time imaging in intact Caenorhabditis elegans

2018

AbstractcGMP is a ubiquitous second messenger that plays a role in sensory signaling and plasticity through its regulation of ion channels and kinases. Previous studies that primarily used genetic and biochemical tools suggest that cGMP is spatiotemporally regulated in multiple sensory modalities, including light, heat, gases, salt and odor. FRET- and GFP-based cGMP sensors were developed to visualize cGMP in primary cell culture and Caenorhabditis elegans to corroborate these findings. While a FRET-based sensor has been used in an intact animal to visualize cGMP, the requirement of a multiple emission system limits its ability to be used on its own as well as with other sensors and fluores…

How the country-of-origin impacts wine traders’ mental representation about wines: A study in a world wine trade fair

2020

Using data collected at a world wine trade fair, we study how the country-of-origin impacts wine traders’ mental representation about wines. In the analysis we use traditional exporters in Old (France) and New (Argentina) world wine countries in comparison to non-traditional exporters in Old (Switzerland) and New (Brazil) world wine countries. Three main findings are reported. First, the country-of-origin of wines was more important on guiding participants’ representations, than the category of countries the traders came from. Second, participants’ evocations were more precise and specific for traditional wine-exporting countries than for less traditional wine exporting countries. Finally, …

Measuring trunk orientation with a CMOS camera: feasibility and accuracy.

2007

International audience; The purpose of this study was to develop and validate a new tool to objectively quantify trunk orientation at the bedside, especially dedicated to the measurement of the lateropulsion in acute and subacute stroke patients. We developed software to analyze 2D movement with a CMOS camera (Logitech Quickcam Pro 4000) and to calculate the orientation of a segment defined by two color markers. First, the accuracy, reproducibility and noise when measuring segment orientations were evaluated with the CMOS camera placed in different positions, and second trunk orientation was measured in static and in dynamic conditions both with a CMOS camera and with a gold standard 3D vid…

Essential omega-3 fatty acids tune microglial phagocytosis of synaptic elements in the developing brain

2019

SUMMARYOmega-3 fatty acids (n-3 polyunsaturated fatty acids; n-3 PUFAs) are essential for the functional maturation of the brain. Westernization of dietary habits in both developed and developing countries is accompanied by a progressive reduction in dietary intake of n-3 PUFAs. Low maternal intake of n-3 PUFAs has been linked to neurodevelopmental diseases in epidemiological studies, but the mechanisms by which a n-3 PUFA dietary imbalance affects CNS development are poorly understood. Active microglial engulfment of synaptic elements is an important process for normal brain development and altered synapse refinement is a hallmark of several neurodevelopmental disorders. Here, we identify …

The first COVID-19 lockdown reveals an ambivalent relation of French parents with food pleasure: the struggle to find a balance

2021

International audience; In France, a first COVID-19 lockdown took place from March-May 2020. Using an online survey including three open-ended questions, this study explored parents' experiences regarding changes in their family's eating behaviors during this lockdown. French parents (n = 498, 71% mothers) of young children were invited to describe which food-related changes they (1) perceived as positive during the lockdown, (2) perceived as negative, and (3) would like to maintain after the lockdown. A thematic analysis revealed that parents appreciated the choice of more local, fresh and high-quality foods, the time to prepare foods (homemade dishes, new recipes) and cooking and eating w…

Estudio de la función de los factores de transcripción PBX en la diferenciación a neurona dopaminérgica del bulbo olfatorio de ratón

2017

[EN] Dopamine signalling regulates a variety of complex behaviours and defects in dopaminergic neuron function or survival result in severe human pathologies such as Parkinson´s disease. All dopaminergic neurons are characterized by the expression of a battery of genes that code for a set of proteins required for the synthesis, release and re-uptake of dopamine and all together are called the DA pathway genes. Therefore, understanding how this set of genes are transcriptionally activated in a coordinated manner is the first step to discover the clues of dopaminergic terminal differentiation. The dopamine pathway genes are highly conserved throughout evolution. Studies in the nematode C.eleg…

Layer-Specific Refinement of Sensory Coding in Developing Mouse Barrel Cortex

2017

Rodent rhythmic whisking behavior matures during a critical period around 2 weeks after birth. The functional adaptations of neocortical circuitry during this developmental period remain poorly understood. Here, we characterized stimulus-evoked neuronal activity across all layers of mouse barrel cortex before, during, and after the onset of whisking behavior. Employing multi-electrode recordings and 2-photon calcium imaging in anesthetized mice, we tested responses to rostro-caudal whisker deflections, axial "tapping" stimuli, and their combination from postnatal day 10 (P10) to P28. Within this period, whisker-evoked activity of neurons displayed a general decrease in layer 2/3 (L2/3) and …