A sodium background conductance controls the spiking pattern of mouse adrenal chromaffin cells in situ.

Key Points: Mouse chromaffin cells in acute adrenal slices exhibit two distinct spiking patterns, a repetitive mode and a bursting mode. A sodium background conductance operates at rest as demonstrated by the membrane hyperpolarization evoked by a low Na -containing extracellular saline. This sodium background current is insensitive to TTX, is not blocked by Cs ions and displays a linear I-V relationship at potentials close to chromaffin cell resting potential.

Melatonin (MEL) and its use in circadian rhythm sleep-wake disorders: Recommendations of the French Medical and Research Sleep Society (SFRMS).

The French society of medical research on sleep (SFRMS) appointed a group of experts to conduct a consensus conference in order to study the indications and prescription status of exogenous melatonin (MEL). Eleven sleep physicians/researchers investigated in subgroups the use of MEL in different domains of healthcare in line with their subspecialties (circadian sleep/wake rhythm disorders, psychiatric disorders, neurological disorders, pediatric and neurodevelopmental disorders). In this article we present a summary of the main conclusions of the expert group on MEL therapy in circadian sleep/wake rhythm disorders such us delayed sleep-wake disorder, non-24-hour sleep wake rhythm disorder and jet lag.

A refined method to monitor arousal from hibernation in the European hamster.

Background: Hibernation is a physiological and behavioural adaptation that permits survival during periods of reduced food availability and extreme environmental temperatures. This is achieved through cycles of metabolic depression and reduced body temperature (torpor) and rewarming (arousal). Rewarming from torpor is achieved through the activation of brown adipose tissue (BAT) associated with a rapid increase in ventilation frequency.

[Insights and recommendations on the sleep of children and adolescents].

Sleep disorders in children are a frequent complaint, whether in maternal and child welfare, paediatrics or child psychiatry consultations. The subject should be taken into consideration in view of the significant consequences that these disorders can have on the child and his entourage. Since organic causes have been excluded, a good knowledge of sleep physiology and rhythms will enable the early childhood professional to effectively help parents to establish habits conducive to good sleep in their child.

New insights on the modeling of the molecular mechanisms underlying neural maps alignment in the midbrain.

We previously identified and modeled a principle of visual map alignment in the midbrain involving the mapping of the retinal projections and concurrent transposition of retinal guidance cues into the superior colliculus providing positional information for the organization of cortical V1 projections onto the retinal map (Savier et al., 2017). This principle relies on mechanisms involving Epha/Efna signaling, correlated neuronal activity and axon competition.

Atypical hemolytic and uremic syndrome due to C3 mutation in pancreatic islet transplantation: a case report.

Background: We here report on the first observation of a C3 mutation that is related to atypical hemolytic and uremic syndrome (aHUS), which occurred in a pancreatic islet transplant patient. Immunosuppressive treatments, such as calcineurin inhibitors, have been linked to undesirable effects like nephrotoxicity.

Case Presentation: A 40-year-old man with brittle diabetes, who was included in the TRIMECO trial, became insulin-independent 2 months after pancreatic islet transplantation.

Melatonin (MEL) and its use in neurological diseases and insomnia: Recommendations of the French Medical and Research Sleep Society (SFRMS).

The French Medicine and Research Sleep Society had organized a consensus conference about sleep/wake circadian rhythms and their disorders. During this conference a subgroup of 11 sleep doctors/researchers looked specifically at the use of MEL in different pathologies. This article gives a summary of the main results of MEL therapy in some neurological diseases and insomnia approved by this consensus group.

Thyroid hormone receptors are required for the melatonin-dependent control of Rfrp gene expression in mice.

Mammals adapt to seasons using a neuroendocrine calendar defined by the photoperiodic change in the nighttime melatonin production. Under short photoperiod, melatonin inhibits the pars tuberalis production of TSHβ, which, in turn, acts on tanycytes to regulate the deiodinase 2/3 balance resulting in a finely tuned seasonal control of the intra-hypothalamic thyroid hormone T3. Despite the pivotal role of this T3 signaling for synchronizing reproduction with the seasons, T3 cellular targets remain unknown.

Metabolic Implications of Exposure to Light at Night: Lessons from Animal and Human Studies.

Lately, the incidence of overweight, obesity, and type 2 diabetes has shown a staggering increase. To prevent and treat these conditions, one must look at their etiology. As life on earth has evolved under the conditions of nature's 24-hour light/dark cycle, it seems likely that exposure to artificial light at night (LAN) would affect physiology.

Metabolic Effects of Light at Night are Time- and Wavelength-Dependent in Rats.

Objective: Intrinsically photosensitive retinal ganglion cells are most sensitive to short wavelengths and reach brain regions that modulate biological rhythms and energy metabolism. The increased exposure nowadays to artificial light at night (ALAN), especially short wavelengths, perturbs our synchronization with the 24-hour solar cycle. Here, the time- and wavelength dependence of the metabolic effects of ALAN are investigated.

Ventral striatum regulates behavioral response to ethanol and MDMA combination.

Our previous studies consistently showed that MDMA-induced locomotor hyperactivity is dramatically increased by coadministration of ethanol (EtOH) in rats, indicating possible potentiation of MDMA abuse liability. Thus, we aimed to identify the brain region(s) and neuropharmacological substrates involved in the pharmacodynamics of this potentiation. We first showed that potentiation of locomotor activity by the combination of ip administration of EtOH (1.

Involvement of the lateral habenula in fear memory.

Increasing evidence points to the engagement of the lateral habenula (LHb) in the selection of appropriate behavioral responses in aversive situations. However, very few data have been gathered with respect to its role in fear memory formation, especially in learning paradigms in which brain areas involved in cognitive processes like the hippocampus (HPC) and the medial prefrontal cortex (mPFC) are required. A paradigm of this sort is trace fear conditioning, in which an aversive event is preceded by a discrete stimulus, generally a tone, but without the close temporal contiguity allowing for their association based on amygdala-dependent information processing.

Disturbances of Continuous Sleep and Circadian Rhythms Account for Behavioral Difficulties in Children with Autism Spectrum Disorder.

Sleep disorders are among the most common comorbidities in children with Autism Spectrum Disorder (ASD), and subjectively defined sleep disturbances have been related to ASD symptom severity. However, no study has investigated the differential impact of objectively measured sleep and circadian rhythm disturbances on behavioral difficulties in this population. Fifty-two children with ASD aged 3-10 years underwent assessments of sleep and circadian rest-activity rhythms objectively with actigraphy and subjectively with the Children's Sleep Habits Questionnaire.

Promoting attachment between parents and neonates despite the COVID-19 pandemic.

Social distancing is the only option available during the COVID-19 pandemic until a vaccine is developed. However, this is having a major impact on human relationships and bonding between parents and neonates is a major concern. Separation during this health emergency could have lifelong consequences for offspring, and there are even greater concerns if newborn infants are sick or vulnerable and need intensive care.

Absence of Subcerebral Projection Neurons Is Beneficial in a Mouse Model of Amyotrophic Lateral Sclerosis.

Objective: Recent studies carried out on amyotrophic lateral sclerosis patients suggest that the disease might initiate in the motor cortex and spread to its targets along the corticofugal tracts. In this study, we aimed to test the corticofugal hypothesis of amyotrophic lateral sclerosis experimentally.

Methods: Sod1 and Fezf2 knockout mouse lines were crossed to generate a model that expresses a mutant of the murine Sod1 gene ubiquitously, a condition sufficient to induce progressive motor symptoms and premature death, but genetically lacks corticospinal neurons and other subcerebral projection neurons, one of the main populations of corticofugal neurons.

Night-sleep Duration Trajectories and Behavior in Preschoolers: Results from a Prospective Birth Cohort Study.

Short sleep duration is associated with concomitant behavioral difficulties, but the longitudinal association between sleep duration and later behavior in early childhood remains unclear. The aim was to study the association between sleep duration trajectories throughout preschool and behavior at age 5-6 years. 1021 children of the French birth-cohort EDEN were included in this study.

Evidence for Common Horizontal Transmission of among Ants and Ant Crickets: Kleptoparasitism Added to the List.

While , an intracellular bacterial symbiont, is primarily transmitted maternally in arthropods, horizontal transmission between species has been commonly documented. We examined kleptoparasitism as a potential mechanism for horizontal transmission, using ant crickets and their host ants as the model system. We compared prevalence and diversity of across multiple ant cricket species with different degrees of host specificity/integration level.

[Psychopathological consequences of confinement].

The psychological effects of isolation have already been described in the literature (polar expeditions, submarines, prison). Nevertheless, the scale of confinement implemented during the COVID-19 pandemic is unprecedented. In addition to reviewing the published studies, we need to anticipate the psychological problems that could arise during or at a distance from confinement.

The receptor tyrosine kinase EPHB6 regulates catecholamine exocytosis in adrenal gland chromaffin cells.

The erythropoietin-producing human hepatocellular receptor EPH receptor B6 (EPHB6) is a receptor tyrosine kinase that has been shown previously to control catecholamine synthesis in the adrenal gland chromaffin cells (AGCCs) in a testosterone-dependent fashion. EPHB6 also has a role in regulating blood pressure, but several facets of this regulation remain unclear. Using amperometry recordings, we now found that catecholamine secretion by AGCCs is compromised in the absence of EPHB6.