Kjeldgaard Witt (egyptneedle8)

Significance Statement Huntington's disease (HD) is a neurodegenerative disease characterized by prominent motor manifestations in addition to nonmotor changes in behavior and cognition. Several studies have provided evidences that the neuropathological hallmark of HD begins and progresses before the conventional diagnosis can be made. Here using an animal model, we identified deficit in motor skill in early stage of the disease. Remarkably these early behavioural deficits are accompanied by aberrant plasticity at synapses between motor cortex and dorsal striatum. This study not only gives a better understanding in the synaptopathic mechanisms of HD, but also highlights that deficit in motor skill consolidation-dependent synaptic plasticity at motor cortex to dorsal striatum synapses represents an early biomarker for Huntington's disease. Copyright © 2020 Glangetas et al.There has not been a major change in how neuroscientists approach stereotaxic methods in decades. Here we present a new stereotaxic method that provides an alternative approach to a traditional u-frame stereotaxic device and reduces costs, surgical time, and aids repeatability. The RatHat brain implantation system is a 3D printable stereotaxic device for rats that is fabricated prior to surgery and fits to the shape of the skull. RatHat builds are directly implanted into the brain without the need for head-leveling or coordinate-mapping during surgery. The RatHat can be used in conjunction with the traditional u-frame stereotaxic device, but does not require the use of a micromanipulator for successful implantations. Each RatHat contains several primary components including the implant for mounting intracranial components, the surgical stencil for targeting drill sites, and the protective cap for preventing damage from impacts and debris. Each component serves a unique function and can be used together or sepill holes, and a RatHat places components in the brain using atlas coordinates. The RatHat is an easily shared resource facilitating open science goals for replications and the archiving of specific experimental applications. Copyright © 2020 Allen et al.City-size distributions are known to be well approximated by power laws across a wide range of countries. But such distributions are also meaningful at other spatial scales, such as within certain regions of a country. Using data from China, France, Germany, India, Japan, and the United States, we first document that large cities are significantly more spaced out than would be expected by chance alone. We next construct spatial hierarchies for countries by first partitioning geographic space using a given number of their largest cities as cell centers and then continuing this partitioning procedure within each cell recursively. We find that city-size distributions in different parts of these spatial hierarchies exhibit power laws that are, again, far more similar than would be expected by chance alone-suggesting the existence of a spatial fractal structure. Copyright © 2020 the Author(s). Published by PNAS.Chronic inflammation during Alzheimer's disease (AD) is most often attributed to sustained microglial activation in response to amyloid-β (Aβ) plaque deposits and cell death. However, cytokine release and microgliosis are consistently observed in AD transgenic animal models devoid of such pathologies, bringing into question the underlying processes that may be at play during the earliest AD-related immune response. We propose that this plaque-independent inflammatory reaction originates from neurons burdened with increasing levels of soluble and oligomeric Aβ, which are known to be the most toxic amyloid species within the brain. Laser microdissected neurons extracted from preplaque amyloid precursor protein (APP) transgenic rats were found to produce a variety of potent immune factors, both at the transcript and protein levels. Neuron-derived cytokines correlated with the extent of microglial activati