Neuronal dendrites must relay synaptic inputs over long distances, but the mechanisms by which activity-evoked intracellular signals propagate over macroscopic distances remain unclear. Here, we discovered a system of periodically arranged endoplasmic reticulum-plasma membrane (ER-PM) junctions tiling the plasma membrane of dendrites at ∼1 μm intervals, interlinked by a meshwork of ER tubules patterned in a ladder-like array. Populated with Junctophilin-linked plasma membrane voltage-gated Ca channels and ER Ca-release channels (ryanodine receptors), ER-PM junctions are hubs for ER-PM crosstalk, fine-tuning of Ca homeostasis, and local activation of the Ca/calmodulin-dependent protein kinase II.
View Article and Find Full Text PDFThe proteins SFPQ (splicing Factor Proline/Glutamine rich) and NONO (non-POU domain-containing octamer-binding protein) are mammalian members of the Drosophila Behaviour/Human Splicing (DBHS) protein family, which share 76% sequence identity in their conserved 320 amino acid DBHS domain. SFPQ and NONO are involved in all steps of post-transcriptional regulation and are primarily located in mammalian paraspeckles: liquid phase-separated, ribonucleoprotein sub-nuclear bodies templated by NEAT1 long non-coding RNA. A combination of structured and low-complexity regions provide polyvalent interaction interfaces that facilitate homo- and heterodimerisation, polymerisation, interactions with oligonucleotides, mRNA, long non-coding RNA, and liquid phase-separation, all of which have been implicated in cellular homeostasis and neurological diseases including neuroblastoma.
View Article and Find Full Text PDFBr J Oral Maxillofac Surg
December 2024
Undergraduates in medicine should receive a basic education to ensure understanding of dental concepts, including oral cancer, basic dental health advice, and oral and maxillofacial surgery (OMFS). This review aims to explore the exposure of OMFS and dental education in the UK medical undergraduate curriculum and follows PRISMA protocols. Four databases were used to search for literature: MEDLINE, EMBASE, SCOPUS, and Google Scholar.
View Article and Find Full Text PDFThe ketogenic diet is an effective treatment for drug-resistant epilepsy, but the therapeutic mechanisms are poorly understood. Although ketones are able to fuel the brain, it is not known whether ketones are directly metabolized by neurons on a time scale sufficiently rapid to fuel the bioenergetic demands of sustained synaptic transmission. Here, we show that nerve terminals can use the ketone β-hydroxybutyrate in a cell- autonomous fashion to support neurotransmission in both excitatory and inhibitory nerve terminals and that this flexibility relies on Ca dependent upregulation of mitochondrial metabolism.
View Article and Find Full Text PDFWe developed a significantly improved genetically encoded quantitative adenosine triphosphate (ATP) sensor to provide real-time dynamics of ATP levels in subcellular compartments. iATPSnFR2 is a variant of iATPSnFR1, a previously developed sensor that has circularly permuted superfolder green fluorescent protein (GFP) inserted between the ATP-binding helices of the -subunit of a bacterial F-F ATPase. Optimizing the linkers joining the two domains resulted in a ~fivefold to sixfold improvement in the dynamic range compared to the previous-generation sensor, with excellent discrimination against other analytes, and affinity variants varying from 4 µM to 500 µM.
View Article and Find Full Text PDFIntroduction: Clinical success of donation after circulatory death (DCD) heart transplantation is leading to growing adoption of this technique. In comparison to procurement from a brain-dead donor, DCD requires additional resources. The economic impact of DCD heart transplantation from the hospital perspective is not well known.
View Article and Find Full Text PDFResearchers are increasingly using insights derived from large-scale, electronic healthcare data to inform drug development and provide human validation of novel treatment pathways and aid in drug repurposing/repositioning. The objective of this study was to determine whether treatment of patients with multiple sclerosis with dimethyl fumarate, an activator of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, results in a change in incidence of type 2 diabetes and its complications. This retrospective cohort study used administrative claims data to derive four cohorts of adults with multiple sclerosis initiating dimethyl fumarate, teriflunomide, glatiramer acetate or fingolimod between January 2013 and December 2018.
View Article and Find Full Text PDFThe endoplasmic reticulum (ER) is an important regulator of in cells and dysregulation of ER calcium homeostasis can lead to numerous pathologies. Understanding how various pharmacological and genetic perturbations of ER homeostasis impacts cellular physiology would likely be facilitated by more quantitative measurements of ER levels that allow easier comparisons across conditions. Here, we developed a ratiometric version of our original ER-GCaMP probe that allows for more quantitative comparisons of the concentration of in the ER across cell types and sub-cellular compartments.
View Article and Find Full Text PDFAlthough we have learned much about how the brain fuels its functions over the last decades, there remains much still to discover in an organ that is so complex. This article lays out major gaps in our knowledge of interrelationships between brain metabolism and brain function, including biochemical, cellular, and subcellular aspects of functional metabolism and its imaging in adult brain, as well as during development, aging, and disease. The focus is on unknowns in metabolism of major brain substrates and associated transporters, the roles of insulin and of lipid droplets, the emerging role of metabolism in microglia, mysteries about the major brain cofactor and signaling molecule NAD, as well as unsolved problems underlying brain metabolism in pathologies such as traumatic brain injury, epilepsy, and metabolic downregulation during hibernation.
View Article and Find Full Text PDFRecent advances have expanded the role of lipid droplets (LDs) beyond passive lipid storage, implicating their involvement in various metabolic processes across mammalian tissues. Neuronal LDs, long debated in existence, have been identified in several neural structures, raising questions about their contribution to neurodegenerative disorders. Elucidating the specific chemical makeup of these organelles within neurons is critical for understanding their implication in neural pathologies.
View Article and Find Full Text PDFUnderstanding protein behaviour is crucial for developing functional solvent systems. Ionic liquids (ILs) are designer salts with versatile ion combinations, where some suppress unfavourable protein behaviour. This work utilizes small angle X-ray scattering (SAXS) to investigate the size and shape changes of model protein hen egg white lysozyme (HEWL) in 137 IL and salt solutions.
View Article and Find Full Text PDFThe evolution of the medial longitudinal arch (MLA) is one of the most impactful adaptations in the hominin foot that emerged with bipedalism. When and how it evolved in the human lineage is still unresolved. Complicating the issue, clinical definitions of flatfoot in living Homo sapiens have not reached a consensus.
View Article and Find Full Text PDFThis paper reports results from a large-scale randomized controlled trial assessing whether counter-stereotypical messaging and partisan cues can induce people to get COVID-19 vaccines. The study used a 27-s video compilation of Donald Trump's comments about the vaccine from Fox News interviews and presented the video to millions of U.S.
View Article and Find Full Text PDFControl of neurotransmission efficacy is central to theories of how the brain computes and stores information. Presynaptic G-protein coupled receptors (GPCRs) are critical in this problem as they locally influence synaptic strength and can operate on a wide range of time scales. Among the mechanisms by which GPCRs impact neurotransmission is by inhibiting voltage-gated calcium (Ca) influx in the active zone.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 2022
Trabecular bone-the spongy bone inside marrow cavities-adapts to its mechanical environment during growth and development. Trabecular structure can therefore be interpreted as a functional record of locomotor behavior in extinct vertebrates. In this paper, we expand upon traditional links between form and function by situating ontogenetic trajectories of trabecular bone in four primate species into the broader developmental context of neural development, locomotor control, and ultimately life history.
View Article and Find Full Text PDFThrough an expansive international effort that involved data collection on 12 small-angle X-ray scattering (SAXS) and four small-angle neutron scattering (SANS) instruments, 171 SAXS and 76 SANS measurements for five proteins (ribonuclease A, lysozyme, xylanase, urate oxidase and xylose isomerase) were acquired. From these data, the solvent-subtracted protein scattering profiles were shown to be reproducible, with the caveat that an additive constant adjustment was required to account for small errors in solvent subtraction. Further, the major features of the obtained consensus SAXS data over the q measurement range 0-1 Å are consistent with theoretical prediction.
View Article and Find Full Text PDFAPOBEC3 enzymes are polynucleotide deaminases, converting cytosine to uracil on single-stranded DNA (ssDNA) and RNA as part of the innate immune response against viruses and retrotransposons. APOBEC3G is a two-domain protein that restricts HIV. Although X-ray single-crystal structures of individual catalytic domains of APOBEC3G with ssDNA as well as full-length APOBEC3G have been solved recently, there is little structural information available about ssDNA interaction with the full-length APOBEC3G or any other two-domain APOBEC3.
View Article and Find Full Text PDFHigh-resolution computed tomography images were acquired for 31 proximal human tibiae, age 8 to 37.5 years, from Norris Farms #36 cemetery site (A.D.
View Article and Find Full Text PDFThe solution state structure of κ-carrageenan is typically described as a 'random coil', to indicate a lack of defined secondary structure elements. From this starting point the assignment of an optical-rotation-detected change that follows the introduction of particular ions to such solutions as a 'coil-to-helix transition' seems unambiguous, and thus the canonical description of this important biopolymer's gelling behaviour was born. However, the notion that κ-carrageenan exists in solution as a random coil, devoid of secondary structure, has been questioned a number of times previously in the literature, particularly by the molecular modelling and NMR communities.
View Article and Find Full Text PDFInitial warfarin dosing and time in therapeutic range (TTR) are poorly characterized for early post-operative left ventricular assist device (LVAD) patients. This study evaluated TTR after LVAD implantation compared between patients receiving low-dose (<3 mg) and high-dose (≥3 mg) warfarin. This single-center, retrospective analysis included 234 LVAD patients who received warfarin within 5 days of implantation.
View Article and Find Full Text PDFObjective: The development of bipedalism is a very complex activity that contributes to shaping the anatomy of the foot. The talus, which starts ossifying in utero, may account for the developing stages from the late gestational phase onwards. Here, we explore the early development of the talus in both its internal and external morphology to broaden the knowledge of the anatomical changes that occur during early development.
View Article and Find Full Text PDFIntensity-correlation measurements allow access to nanostructural information on a range of ordered and disordered materials beyond traditional pair-correlation methods. In real space, this information can be expressed in terms of a pair-angle distribution function (PADF) which encodes three- and four-body distances and angles. To date, correlation-based techniques have not been applied to the analysis of microstructural effects, such as preferred orientation, which are typically investigated by texture analysis.
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