Publications by authors named "Thomas Arnold"

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  • Clinical testing after COVID hospitalization often misses lingering cardiac issues that could lead to more heart problems later on.
  • An exercise stress echocardiography (ESE) study with 15 recovering patients showed they had lower heart function and higher heart rate compared to healthy individuals during physical activity.
  • The findings indicate that post-COVID patients may experience hidden heart dysfunction that could affect their recovery and long-term health, possibly due to factors like autonomic dysfunction or microvascular damage.
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  • Snakebite envenoming (SBE) causes over 500,000 deaths or serious injuries annually, and a phase II clinical trial was conducted to evaluate the safety and efficacy of varespladib methyl, an oral treatment, in patients bitten by venomous snakes.
  • The trial, which was double-blind and placebo-controlled, enrolled patients in emergency departments in the USA and India, assessing changes in severity of snakebite symptoms using the Snakebite Severity Score (SSS) after treatment.
  • Results indicated no significant difference in SSS improvement between the varespladib and placebo groups overall, but early treatment (within 5 hours of the bite) showed potential benefits in illness severity and recovery outcomes.
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  • - Microglia are the central nervous system's immune cells, playing essential roles in brain development and maintaining neuron activity, but their involvement at the blood-brain barrier (BBB) in healthy brains is less understood.
  • - A study using the CSF1R inhibitor PLX5622 to deplete microglia showed that they are not crucial for maintaining the structure or function of the healthy BBB, despite their close contact with endothelial cells.
  • - However, treatment with PLX5622 was found to affect cholesterol metabolism in brain endothelial cells independently of microglial presence, indicating that the drug has unintended effects on brain blood vessels.
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Congenital hydrocephalus (CH), occurring in approximately 1/1,000 live births, represents an important clinical challenge due to the limited knowledge of underlying molecular mechanisms. The discovery of novel CH genes is thus essential to shed light on the intricate processes responsible for ventricular dilatation in CH. Here, we identify FLVCR1 (feline leukemia virus subgroup C receptor 1) as a gene responsible for a severe form of CH in humans and mice.

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  • Choline is a crucial nutrient needed by the body for processes like building cell membranes and neurotransmission, with the brain having the highest demand for it.
  • The protein FLVCR2, found in cells at the blood-brain barrier, is identified as the main transporter for choline into the brain, unlike another related protein, FLVCR1, which is not as active there.
  • Research includes structural analysis of FLVCR2 using cryo-electron microscopy, which shows how choline binds and is transported, offering potential insights for delivering therapies into the brain more effectively.
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Background: Portable low-field-strength magnetic resonance imaging (MRI) systems represent a promising alternative to traditional high-field-strength systems with the potential to make MR technology available at scale in low-resource settings. However, lower image quality and resolution may limit the research and clinical potential of these devices. We tested two super-resolution methods to enhance image quality in a low-field MR system and compared their correspondence with images acquired from a high-field system in a sample of young people.

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Opioid abuse in the United States has been increasing at an alarming rate over the past 20 years. Sex differences are documented for the rates of opioid-related overdoses, abuse patterns, and drug-induced physiological effects. In our previous study, we demonstrated that chronic oxycodone administration in young female rats is associated with neurodegeneration in the brain.

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  • * The study identifies a specific microglial state that responds to type I interferon (IFN-I) and actively engulfs neurons during the early postnatal development of the somatosensory cortex.
  • * Alterations in IFN-I signaling impact microglial function, leading to neuronal damage and increased excitatory neurons, which may contribute to heightened sensitivity to touch, highlighting the importance of microglia in brain development and homeostasis.
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Objective: Among adolescents, disinhibited eating and anxiety commonly co-occur. Precision intervention approaches targeting unique mechanistic vulnerabilities that contribute to disinhibited eating and anxiety may therefore be helpful. However, the effectiveness of such interventions hinges on knowledge of between- and within-person associations related to disinhibited eating, anxiety, and related processes.

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The recent proliferation of new Cre and CreER recombinase lines provides researchers with a diverse toolkit to study microglial gene function. To determine how best to apply these lines in studies of microglial gene function, a thorough and detailed comparison of their properties is needed. Here, we examined four different microglial CreER lines (Cx3cr1, Cx3cr1, P2ry12, and Tmem119), focusing on (1) recombination specificity, (2) leakiness (the degree of tamoxifen-independent recombination in microglia and other cells), (3) the efficiency of tamoxifen-induced recombination, (4) extraneural recombination (the degree of recombination in cells outside of the CNS, particularly myelo/monocyte lineages), and (5) off-target effects in the context of neonatal brain development.

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Integrins are cell adhesion receptors that dimerize to mediate cell-cell interactions and regulate processes, including proliferation, inflammation, and tissue repair. The role of integrins in regulating insulin signaling is incompletely understood. We have previously shown that binding of the integrin ligand milk fat globule epidermal growth factor like 8 (MFGE8) to the αvβ5 integrin promotes termination of insulin receptor signaling in mice.

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Choline is an essential nutrient that the human body needs in vast quantities for cell membrane synthesis, epigenetic modification, and neurotransmission. The brain has a particularly high demand for choline, but how it enters the brain has eluded the field for over fifty years. The MFS transporter FLVCR1 was recently determined to be a choline transporter, and while this protein is not highly expressed at the blood-brain barrier (BBB), its relative FLVCR2 is.

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Cruciferous plants produce sulforaphane (SFN), an inhibitor of nuclear histone deacetylases (HDACs). In humans and other mammals, the consumption of SFN alters enzyme activities, DNA-histone binding, and gene expression within minutes. However, the ability of SFN to act as an HDAC inhibitor in nature, disrupting the epigenetic machinery of insects feeding on these plants, has not been explored.

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Microglia diversity emerges from interactions between intrinsic genetic programs and environment-derived signals, but how these processes unfold and interact in the developing brain remains unclear. Here, we show that radial glia-expressed integrin beta 8 (ITGB8) expressed in radial glia progenitors activates microglia-expressed TGFβ1, permitting microglial development. Domain-restricted deletion of in these progenitors establishes complementary regions with developmentally arrested "dysmature" microglia that persist into adulthood.

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The APOE4 allele is the strongest genetic risk factor for late-onset Alzheimer's disease (AD). The contribution of microglial APOE4 to AD pathogenesis is unknown, although APOE has the most enriched gene expression in neurodegenerative microglia (MGnD). Here, we show in mice and humans a negative role of microglial APOE4 in the induction of the MGnD response to neurodegeneration.

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Following the reaction of biological membranes to external stimuli reveals fundamental insights into cellular function. Here, self-assembled lipid monolayers act as model membranes containing photoswitchable azobenzene glycolipids for investigating structural response during isomerization by combining Langmuir isotherms with X-ray scattering. Controlled in-situ trans/cis photoswitching of the azobenzene N = N double bond alters the DPPC monolayer structure, causing reproducible changes in surface pressure and layer thickness, indicating monolayer reorientation.

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Loss of control (LOC)-eating, excess weight, and anxiety are robustly linked, and are independently associated with markers of poorer cardiometabolic health, including hypertension. However, no study has examined whether frequency of LOC-eating episodes among youth with anxiety symptoms and elevated weight status may confer increased risk for hypertension. We examined the relationship between LOC-eating frequency and blood pressure among 39 adolescent girls (14.

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There are several pathophysiological outcomes associated with substance abuse including metabolic disbalance, neurodegeneration, and disordered redox. Drug use in pregnant women is a topic of great concern due to developmental harm which may occur during gestation and the associated complications in the neonate after delivery. We sought to determine what the trajectory of drug use is like in children aged 0-4 years and mothers of neonates.

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The recent proliferation of new and recombinase lines provides researchers with a diverse toolkit to study microglial gene function. To determine how best to apply these lines in studies of microglial gene function, a thorough and detailed comparison of their properties is needed. Here, we examined four different microglial lines (, , , ), focusing on (1) recombination specificity; (2) leakiness - degree of non-tamoxifen recombination in microglia and other cells; (3) efficiency of tamoxifen-induced recombination; (4) extra-neural recombination -the degree of recombination in cells outside the CNS, particularly myelo/monocyte lineages (5) off-target effects in the context of neonatal brain development.

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We present a novel approach for extracting metric volume information of fruits and vegetables from short monocular video sequences and associated inertial data recorded with a hand-held smartphone. Estimated segmentation masks from a pre-trained object detector are fused with the predicted change in relative pose obtained from the inertial data to predict the class and volume of the objects of interest. Our approach works with simple RGB video frames and inertial data which are readily available from modern smartphones.

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When viruses like SARS-CoV-2 infect cells, they reprogram the repertoire of cellular and viral transcripts that are being translated to optimize their strategy of replication, often targeting host translation initiation factors, particularly eIF4F complex consisting of eIF4E, eIF4G and eIF4A. A proteomic analysis of SARS-CoV-2/human proteins interaction revealed viral Nsp2 and initiation factor eIF4E2, but a role of Nsp2 in regulating translation is still controversial. HEK293T cells stably expressing Nsp2 were tested for protein synthesis rates of synthetic and endogenous mRNAs known to be translated via cap- or IRES-dependent mechanism under normal and hypoxic conditions.

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Enterocytes modulate the extent of postprandial lipemia by storing dietary fats in cytoplasmic lipid droplets (cLDs). We have previously shown that the integrin ligand MFGE8 links absorption of dietary fats with activation of triglyceride (TG) hydrolases that catabolize cLDs for chylomicron production. Here, we identify CES1D as the key hydrolase downstream of the MFGE8-αvβ5 integrin pathway that regulates catabolism of diet-derived cLDs.

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As a result of the availability of modern software and hardware, Bayesian analysis is becoming more popular in neutron and X-ray reflectometry analysis. The understandability and replicability of these analyses may be harmed by inconsistencies in how the probability distributions central to Bayesian methods are represented in the literature. Herein advice is provided on how to report the results of Bayesian analysis as applied to neutron and X-ray reflectometry.

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