Publications by authors named "Hurd R"

Background: Substance use disorder affects over half of incarcerated individuals, with 23% experiencing opioid use disorder specifically. Addressing opioid use disorder in jails is crucial due to its association with increased recidivism and overdose. This study investigates the experiences of peer recovery specialists working with individuals with opioid use disorder and criminal justice involvement, focusing on barriers and facilitators to client connections.

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Objective: Congenital heart disease affects 1% of US births, with many babies requiring major cardiothoracic surgery under cardiopulmonary bypass (CPB), exposing the more critical patients to neurodevelopmental impairment. Optimal surgical parameters to minimize neuronal injury are unknown. We used H MRS and blood ammonia assays in a neonatal pig model of CPB to compare two approaches, complete circulatory arrest (CA) versus antegrade cerebral perfusion (ACP).

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Purpose: To measure and validate elevated succinate in brain during circulatory arrest in a piglet model of cardiopulmonary bypass.

Methods: Using data from an archive of 3T H MR spectra acquired in previous in-magnet studies, dynamic plots of succinate, spectral simulations and difference spectra were generated for analysis and validation.

Results: Elevation of succinate during circulatory arrest was observed and validated.

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The goal of this study was to investigate the origin of brain lactate (Lac) signal in the healthy anesthetized rat after injection of hyperpolarized (HP) [1- C]pyruvate (Pyr). Dynamic two-dimensional spiral chemical shift imaging with flow-sensitizing gradients revealed reduction in both vascular and brain Pyr, while no significant dependence on the level of flow suppression was detected for Lac. These results support the hypothesis that the HP metabolites predominantly reside in different compartments in the brain (i.

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Purpose: To explore the potential of 3T deuterium metabolic imaging (DMI) using a birdcage H radiofrequency (RF) coil in both healthy volunteers and patients with central nervous system (CNS) lesions.

Methods: A modified gradient filter, home-built H volume RF coil, and spherical k-space sampling were employed in a three-dimensional chemical shift imaging acquisition to obtain high-quality whole-brain metabolic images of H-labeled water and glucose metabolic products. These images were acquired in a healthy volunteer and three subjects with CNS lesions of varying pathologies.

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Alzheimer's disease (AD) pathogenesis is associated with alterations in neurometabolites and cortical microstructure. However, our understanding of alterations in neurochemicals in the prefrontal cortex and their relationship with changes in cortical microstructure in AD remains unclear. Here, we studied the levels of neurometabolites in the left dorsolateral prefrontal cortex (DLPFC) in healthy older adults and patients with amnestic Mild Cognitive Impairments (aMCI) using single-voxel proton-magnetic resonance spectroscopy (H-MRS).

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Here, we report on the development and performance of a robust 3-T single-voxel proton magnetic resonance spectroscopy ( H MRS) experimental protocol and data analysis pipeline for quantifying brain metabolism during cardiopulmonary bypass (CPB) surgery in a neonatal porcine model, with the overall goal of elucidating primary mechanisms of brain injury associated with these procedures. The specific aims were to assess which metabolic processes can be reliably interrogated by H MRS on a 3-T clinical scanner and to provide an initial assessment of brain metabolism during deep hypothermia cardiac arrest (DHCA) surgery and recovery. Fourteen neonatal pigs underwent CPB surgery while placed in a 3-T MRI scanner for 18, 28, and 37°C DHCA studies under hyperglycemic, euglycemic, and hypoglycemic conditions.

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The role of pyruvate dehydrogenase in mediating lipid-induced insulin resistance stands as a central question in the pathogenesis of type 2 diabetes mellitus. Many researchers have invoked the Randle hypothesis to explain the reduced glucose disposal in skeletal muscle by envisioning an elevated acetyl CoA pool arising from increased oxidation of fatty acids. Over the years, in vivo NMR studies have challenged that monolithic view.

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Health service innovation is required to meet the ever-growing demands of modern medicine. This editorial discusses the transformation of the north central London elective orthopaedic network and the essential principles which future integrated care systems could incorporate.

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Hypnosis is the oldest form of Western psychotherapy and a powerful evidence-based treatment for numerous disorders. Hypnotizability is variable between individuals; however, it is a stable trait throughout adulthood, suggesting that neurophysiological factors may underlie hypnotic responsiveness. One brain region of particular interest in functional neuroimaging studies of hypnotizability is the anterior cingulate cortex (ACC).

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Background: Metabolism in tumor shifts from oxidative phosphorylation to inefficient glycolysis resulting in overproduction of lactate (Warburg effect), and cancers may be effectively treated if this imbalance were corrected. The aim of this longitudinal study of glioblastoma in a rat model was to determine whether the ratio of lactate (surrogate marker for glycolysis) to bicarbonate (for oxidative phosphorylation), as measured via in vivo magnetic resonance imaging of hyperpolarized 13C-labeled pyruvate accurately predicts survival.

Methods: C6 Glioma implanted male Wistar rats (N = 26) were treated with an anti-vascular endothelial growth factor antibody B20.

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Brain metabolism during deep hypothermic arrest is active and abnormal, resulting in a buildup of lactate and loss of energy substrates. Antegrade cerebral perfusion prevents these abnormalities.

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Deformable elastomeric spheres are evaluated experimentally as they skip multiple times over a lake surface. Some spheres are embedded with small inertial measurement units to measure the acceleration experienced during water surface impact. A model for multiple impact events shows good agreement between measured acceleration, number of skipping events and distanced traveled.

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Proton MRS ( H MRS) provides noninvasive, quantitative metabolite profiles of tissue and has been shown to aid the clinical management of several brain diseases. Although most modern clinical MR scanners support MRS capabilities, routine use is largely restricted to specialized centers with good access to MR research support. Widespread adoption has been slow for several reasons, and technical challenges toward obtaining reliable good-quality results have been identified as a contributing factor.

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Article Synopsis
  • * C magnetic resonance spectroscopy (MRS) offers potential advantages for detecting metabolism changes but struggles with low sensitivity, mainly used in single voxel measurements, unless enhanced by complex methods like dDNP.
  • * A new method using MRI chemical shift imaging (CSI) with advanced post-processing via tensor decomposition significantly boosts signal-to-noise ratio, allowing effective imaging of glucose metabolism and the Warburg effect without needing hyperpolarization, achieving great spatial and temporal resolution.
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Hyperpolarized C MRI takes advantage of the unprecedented 50 000-fold signal-to-noise ratio enhancement to interrogate cancer metabolism in patients and animals. It can measure the pyruvate-to-lactate conversion rate, k , a metabolic biomarker of cancer aggressiveness and progression. Therefore, it is crucial to evaluate k reliably.

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An experimental home study examined the impact of a pre-sleep protocol for enhancing self-awareness, lucidity, and responsiveness in dreams. It included ingesting the cholinesterase inhibitor galantamine--which is widely reported to increase the frequency of lucid dreaming--prior to engaging in middle-of-the-night meditation and the imaginary reliving of a distressing dream while exercising new responses. Thirty-five participants completed an eight-night study, which included pre- and post-baseline nights and six conditions: waking for 40 min before returning to bed, called Wake-Back-to-Bed (WBTB); Wake-Back-to-Bed plus placebo (WBTB + P); Wake-Back-to-Bed plus galantamine (WBTB + G); meditation and dream reliving (MDR); meditation and dream reliving plus placebo (MDR + P); and meditation and dream reliving plus galantamine (MDR + G).

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Cancer metabolism has emerged as an increasingly attractive target for interfering with tumor growth. Small molecule activators of pyruvate kinase isozyme M2 (PKM2) suppress tumor formation but have an unknown effect on established tumors. We demonstrate that TEPP-46, a PKM2 activator, results in increased glucose consumption, providing the rationale for combining PKM2 activators with the toxic glucose analog, 2-deoxy-D-glucose (2-DG).

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Striking the top of a liquid-filled bottle can shatter the bottom. An intuitive interpretation of this event might label an impulsive force as the culprit in this fracturing phenomenon. However, high-speed photography reveals the formation and collapse of tiny bubbles near the bottom before fracture.

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Purpose: The most common γ-aminobutyric-acid (GABA) editing approach, MEGA-PRESS, uses J-editing to measure GABA distinct from larger overlapping metabolites, but suffers contamination from coedited macromolecules (MMs) comprising 40 to 60% of the observed signal. MEGA-SPECIAL is an alternative method with better MM suppression, but is not widely used primarily because of its relatively poor spatial localization. Our goal was to develop an improved MM-suppressed GABA editing sequence at 3 Tesla.

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Purpose: The intracellular lactate to pyruvate concentration ratio is a commonly used tissue assay biomarker of redox, being proportional to free cytosolic [NADH]/[NAD ]. In this study, we assessed the use of hyperpolarized [1- C]alanine and the subsequent detection of the intracellular products of [1- C]pyruvate and [1- C]lactate as a useful substrate for assessing redox levels in the liver in vivo.

Methods: Animal experiments were conducted to measure in vivo metabolism at baseline and after ethanol infusion.

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Background: Orthopaedic procedures, such as total hip replacement and total knee replacement, are among the commonest surgical procedures in England. The Getting it Right First Time project (GIRFT) aims to deliver improvements in quality and reductions in the cost of NHS orthopaedic care across the country. We will examine whether the planned changes have delivered improvements in the quality of care and patient outcomes.

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Hyperpolarized [1-(13)C]pyruvate MRS provides a unique imaging opportunity to study the reaction kinetics and enzyme activities of in vivo metabolism because of its favorable imaging characteristics and critical position in the cellular metabolic pathway, where it can either be reduced to lactate (reflecting glycolysis) or converted to acetyl-coenzyme A and bicarbonate (reflecting oxidative phosphorylation). Cancer tissue metabolism is altered in such a way as to result in a relative preponderance of glycolysis relative to oxidative phosphorylation (i.e.

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Purpose: Retinal detachments (RDs), a separation of the light-sensitive tissue of the retina from its supporting layers in the posterior eye, isolate retinal cells from their normal supply of nourishment and can lead to their deterioration and death. We identified a new, spontaneous murine model of exudative retinal detachment, nm3342 (new mutant 3342, also referred to as rpea1: retinal pigment epithelium atrophy 1), which we characterize herein.

Methods: The chromosomal position for the recessive nm3342 mutation was determined by DNA pooling, and the causative mutation was discovered by comparison of whole exome sequences of mutant and wild-type controls.

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