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Developmental myelination is a protracted process in the mammalian brain1. One theory for why oligodendrocytes mature so slowly posits that myelination may stabilize neuronal circuits and temper neuronal plasticity as animals age2-4. We tested this theory in the visual cortex, which has a well-defined critical period for experience-dependent neuronal plasticity5. During adolescence, visual experience modulated the rate of oligodendrocyte maturation in visual cortex. To determine whether oligodendrocyte maturation in turn regulates neuronal plasticity, we genetically blocked oligodendrocyte differentiation and myelination in adolescent mice. In adult mice lacking adolescent oligodendrogenesis, a brief period of monocular deprivation led to a significant decrease in visual cortex responses to the deprived eye, reminiscent of the plasticity normally restricted to adolescence. This enhanced functional plasticity was accompanied by a greater turnover of dendritic spines and coordinated reductions in spine size following deprivation. Furthermore, inhibitory synaptic transmission, which gates experience-dependent plasticity at the circuit level, was diminished in the absence of adolescent oligodendrogenesis. These results establish a critical role for oligodendrocytes in shaping the maturation and stabilization of cortical circuits and support the concept of developmental myelination acting as a functional brake on neuronal plasticity.

Introduction: Asking family members to leave during invasive procedures has historically been common practice; however, evidence-based recommendations have altered the trend of family presence during pediatric procedures. The aim of this study was to determine factors related to family members’ choice to be present or absent during fracture reductions in a pediatric emergency department (ED), and their satisfaction with that choice.Methods: We administered role-specific, anonymous surveys to a convenience sample of patients’ family members in the ED of a Level I pediatric trauma center. All family members were given a choice of where to be during the procedure.Results: Twenty-five family members of 18 patients completed surveys. Seventeen family members chose to stay in the room. Family member satisfaction with their decision to be inside or outside the room during the procedure (median = very satisfied) was almost uniformly high and not associated with any of the following variables: previous presence during a medical procedure; provider-reported procedure difficulty, or anxiety levels. Family member perception of procedure success (median = extremely well) was also high and not associated with other variables. Location during the procedure was associated with a desire to be in the same location in the future (Fisher’s exact test, p=0.001). Common themes found among family members’ reasons for their location decisions and satisfaction levels were a desire to support the patient, high staff competence, and their right as parents to choose their location.Conclusion: Family members self-select their location during their child’s fracture reduction to high levels of satisfaction, and they considered the ability to choose their location as important.

Axon specification is a critical step in neuronal development, and the function of glial cells in this process is not fully understood. Here, we show that C. elegans GLR glial cells regulate axon specification of their nearby GABAergic RME neurons through GLR-RME gap junctions. Disruption of GLR-RME gap junctions causes misaccumulation of axonal markers in non-axonal neurites of RME neurons and converts microtubules in those neurites to form an axon-like assembly. We further uncover that GLR-RME gap junctions regulate RME axon specification through activation of the CDK-5 pathway in a calcium-dependent manner, involving a calpain clp-4. Therefore, our study reveals the function of glia-neuron gap junctions in neuronal axon specification and shows that calcium originated from glial cells can regulate neuronal intracellular pathways through gap junctions.

Super-Earths orbiting M dwarf stars may be the most common habitable planets in the Universe. However, their habitability is threatened by intense irradiation from their host stars, which drives the escape of water to space and can lead to surface desiccation. We present simulation results of a box model incorporating deep-water cycling between interior and atmosphere and water loss to space for terrestrial planets of mass 1–8 M ⊕ orbiting in the habitable zone of a late M dwarf. Energy-limited loss decreases with planetary mass, while diffusion-limited loss increases with mass. Depending on where it orbits in the habitable zone, a 1 M ⊕ planet that starts with 3–8 Earth Oceans can end up with an Earthlike surface of oceans and exposed continents; for an 8 M ⊕ super-Earth, that range is 3–12 Earth Oceans. Planets initialized with more water end up as waterworlds with no exposed continents, while planets that start with less water have desiccated surfaces by 5 Gyr. Since the mantles of terrestrial planets can hold much more water than is currently present in Earth's atmosphere, none of our simulations result in Dune planets—such planets may be less common than previously thought. Further, more water becomes sequestered within the mantle for larger planets. A super-Earth at the inner edge of the habitable zone tends to end up as either a waterworld or with a desiccated surface; only a narrow range of initial water inventory yields an Earthlike surface. [ABSTRACT FROM AUTHOR]

Slime's increasing popularity has caused children to be more frequently exposed to glue. There is no comprehensive literature describing pediatric glue-related injuries. This study's purpose is to characterize pediatric glue-related injuries presented to U.S. emergency departments (EDs). We queried the National Electronic Injury Surveillance System for pediatric glue-related injuries from 2009 to 2018. Data were abstracted from discrete and case narrative data. Odds ratios were calculated to determine age-related differences in injuries. An estimated 18,126 pediatric patients were treated in U.S. EDs for glue-related injuries. Injury incidence increased over time. The most frequently injured body part was the eye, and the most common diagnosis was foreign body without documented sequelae. The most common injury mechanism was unintentional splash/squirt/explosion. Younger children were more likely to accidentally ingest glue; older children were more likely to sustain burns. Preventive efforts should focus on personal protective equipment, proper storage/labeling, and supervision of use. [ABSTRACT FROM AUTHOR]

Glia make up roughly half of all cells in the mammalian nervous system and play a major part in nervous system development, function, and disease. Although research in the past few decades has shed light on their morphological and functional diversity, there is still much to be known about key aspects of their development such as the generation of glial diversity and the factors governing proper morphogenesis. Glia of the nematode C. elegans possess many developmental and morphological similarities with their vertebrate counterparts and can potentially be used as a model to understand certain aspects of glial biology owing to advantages such as its genetic tractability and fully mapped cell lineage. In this review, we summarize recent progress in our understanding of genetic pathways that regulate glial development in C. elegans and discuss how some of these findings may be conserved. [ABSTRACT FROM AUTHOR]

As one of the most-studied receptors, Robo plays functions in many biological processes, and its functions highly depend on Slit, the ligand of Robo. Here we uncover a Slitindependent role of Robo in glial migration and show that neurons can release an extracellular fragment of Robo upon cleavage to attract glia during migration in Caenorhabditis elegans. Furthermore, we identified the conserved cell adhesion molecule SYG-1/Neph as a receptor for the cleaved extracellular Robo fragment to mediate glial migration and SYG-1/Neph functions through regulation of the WAVE complex. Our studies reveal a previously unknown Slit-independent function and regulatory mechanism of Robo and show that the cleaved extracellular fragment of Robo can function as a ligand for SYG-1/Neph to guide glial migration. As Robo, the cleaved region of Robo, and SYG-1/Neph are all highly conserved across the animal kingdom, our findings may present a conserved Slit-independent Robo mechanism during brain development. [ABSTRACT FROM AUTHOR]

The Delaware Basin, an evaporite sequence spanning west Texas and southeast New Mexico, is well known for the mining of potassium salts, known as potash. Several companies operate mines in the region, primarily using room-and-pillar techniques. However, the region's karst topography is prone to ground subsidence and sinkhole development when triggered by anthropogenic activities. We explored a region of significant ground subsidence encompassing a potash mine. Incorporating synthetic aperture radar (SAR) images from the advanced land-observing satellite (ALOS) and Sentinel-1A sensors, we used interferometric SAR techniques to detect a significant amount of subsidence located in several distinct areas from 2007 to 2011 and from January to November 2016. To investigate the origin of this subsidence, we considered potash mining by analysing the mine operator's production records. We observed a strong correlation between the total subsidence rate in our area and the potash production rate during 2007-2011. Furthermore, we observed a considerable amount of continuous subsidence during 2016, despite the mine operator suspending potash production on 6 May 2016. As such, the observed subsidence could result in deleterious consequences throughout the region if further action is not taken. [ABSTRACT FROM AUTHOR]

Axon specification is a critical step in neuronal development, and the function of glial cells in this process is not fully understood. Here, we show that C. elegans GLR glial cells regulate axon specification of their nearby GABAergic RME neurons through GLR-RME gap junctions. Disruption of GLR-RME gap junctions causes misaccumulation of axonal markers in non-axonal neurites of RME neurons and converts microtubules in those neurites to form an axon-like assembly. We further uncover that GLR-RME gap junctions regulate RME axon specification through activation of the CDK-5 pathway in a calcium-dependent manner, involving a calpain clp-4. Therefore, our study reveals the function of glia-neuron gap junctions in neuronal axon specification and shows that calcium originated from glial cells can regulate neuronal intracellular pathways through gap junctions. [ABSTRACT FROM AUTHOR]