Publications by authors named "Luke Stewart"

The emergence of COVID-19 spurred the formation of myriad teams to tackle every conceivable aspect of the virus and thwart its spread. Enabled by global digital connectedness, collaboration has become a constant theme throughout the pandemic, resulting in the expedition of the scientific process (including vaccine development), rapid consolidation of global outbreak data and statistics, and experimentation with novel partnerships. To document the evolution of these collaborative efforts, the authors collected illustrative examples as the pandemic unfolded, supplemented with publications from the JMIR COVID-19 Special Issue.

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Objective: Thoracofemoral bypass (TFB) has been used infrequently but is an alternative for select patients with aortoiliac occlusive disease. Limited data are available in the reported data regarding TFB, with all studies small, single-center series. We aimed to describe the perioperative and long-term survival, patency, and rate of major perioperative complications after TFB in a large national registry.

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Objective: Surgical site infection (SSI) is an important complication of lower extremity bypass (LEB) and the rate of SSI after LEB varies widely in the existing literature, ranging from 4% to 31%. Prolonged length of stay (LOS) has been implicated in the occurrence of SSI across multiple surgical disciplines. The impact of preoperative LOS in patients with chronic limb-threatening ischemia (CLTI) undergoing LEB is unknown.

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Objective: Carotid endarterectomy (CEA) with concomitant distal endovascular intervention (CEA+D) is infrequently necessary but has often been used as a salvage maneuver when complications occur during CEA. The present study aimed to determine whether preoperative risk factors associated with CEA requiring CEA+D exist and to evaluate the outcomes compared with isolated CEA.

Methods: The Vascular Quality Initiative CEA registry was used to identify patients who had undergone CEA or CEA+D for asymptomatic or symptomatic carotid stenosis from 2013 to 2019.

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Background: Vein conduit is known to have better patency than prosthetic for infrainguinal bypass. Here we explore if racial disparities exist in infrainguinal bypass vein conduit use amid preoperative patient and systemic factors.

Methods: Retrospective Society for Vascular Surgery Vascular Quality Initiative data for 23,959 infrainguinal bypasses between 2003 and 2017 for occlusive disease were analyzed.

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Optogenetics is widely used in neuroscience to control neural circuits. However, non-invasive methods for light delivery in brain are needed to avoid physical damage caused by current methods. One potential strategy could employ x-ray activation of radioluminescent particles (RPLs), enabling localized light generation within the brain.

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Optical stimulation and imaging of neurons deep in the brain require implantable optical neural probes. External optical access to deeper regions of the brain is limited by scattering and absorption of light as it propagates through tissue. Implantable optoelectronic probes capable of high-resolution light delivery and high-density neural recording are needed for closed-loop manipulation of neural circuits.

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The etiology of late-onset Alzheimer's disease is unknown. Recent epidemiological studies suggest that exposure to high levels of ozone (O) may be a risk factor for late-onset Alzheimer's disease. Nonetheless, whether and how O exposure contributes to AD development remains to be determined.

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Neocortical circuits are sensitive to experience, showing both anatomical and electrophysiological changes in response to altered sensory input. We examined input- and cell-type-specific changes in thalamo- and intracortical pathways during learning using an automated, home-cage sensory association training (SAT) paradigm coupling multi-whisker stimulation to a water reward. We found that the posterior medial nucleus (POm) but not the ventral posterior medial (VPM) nucleus of the thalamus drives increased cortical activity after 24 h of SAT, when behavioral evidence of learning first emerges.

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Here we describe isolation and characterization of macrophage-tumor cell fusions (MTFs) from the blood of pancreatic ductal adenocarcinoma (PDAC) patients. The MTFs were generally aneuploidy, and immunophenotypic characterizations showed that the MTFs express markers characteristic of PDAC and stem cells, as well as M2-polarized macrophages. Single cell RNASeq analyses showed that the MTFs express many transcripts implicated in cancer progression, LINE1 retrotransposons, and very high levels of several long non-coding transcripts involved in metastasis (such as MALAT1).

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O-GlcNAcylation is a ubiquitous and dynamic post-translational modification involving the O-linkage of β--acetylglucosamine to serine/threonine residues of membrane, cytosolic, and nuclear proteins. This modification is similar to phosphorylation and regarded as a key regulator of cell survival and homeostasis. Previous studies have shown that phosphorylation of serine residues on synaptic proteins is a major regulator of synaptic strength and long-term plasticity, suggesting that O-GlcNAcylation of synaptic proteins is likely as important as phosphorylation; however, few studies have investigated its role in synaptic efficacy.

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Background: At present, the resistance to antibiotics is considered the most important reason for Helicobacter pylori (HP) eradication failure. The aim of this study was to estimate the prevalence of antimicrobial resistance of HP strains and to evaluate tailored and empiric therapeutic regimens in patients with peptic ulcer disease associated with infection of this microorganism.

Materials And Methods: Between May 2011 and February 2013, 185 consecutive Polish patients with at least one positive Helicobacter pylori test (urease test, histopathologic examination, and/or culture) underwent eradication therapy.

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Numerous epidemiological studies suggest that individuals who exercise have decreased cardiac morbidity and mortality. Pre-clinical studies in animal models also find clear cardioprotective phenotypes in animals that exercise, specifically characterized by lower myocardial infarction and arrhythmia. Despite the clear benefits, the underlying cellular and molecular mechanisms that are responsible for exercise preconditioning are not fully understood.

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Article Synopsis
  • Metabolic stressors, like food and water deprivation, can increase the likelihood of depression in animals exposed to chronic stress, impacting their sucrose consumption.
  • In an experiment, while 65% of stressed animals initially showed sucrose preference, those deprived of food and water experienced a notable decrease in both intake and preference.
  • The study also found that food deprivation triggered changes in certain stress-related hormones and inflammatory markers in the brain, highlighting the complex interaction between metabolic stress and chronic stress in inducing depression-like behaviors.
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Introduction: Laparoscopy has been introduced into the field of colorectal surgery with the aim of reducing morbidity. One of the major barriers to overcome is the steep learning curve. Robotic surgery offers substantial advantages over traditional laparoscopy, which make the whole procedure more user friendly.

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Current theories on the pathogenesis of autism spectrum disorders (ASD) maintain that the associated cognitive and behavioral symptoms are caused by aberrant synaptic transmission affecting specific brain circuits. Transgenic mouse models have implicated the involvement of cell adhesion proteins in synaptic dysfunction and ASD pathogenesis. Recently, Aoto et al.

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We demonstrate an 11 port count wavelength selective switch (WSS) supporting spatial superchannels of three spatial modes, based on the combination of photonic lanterns and a high-port count single-mode WSS.

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We recently showed that Bendavia, a novel mitochondria-targeting peptide, reduced infarction and no-reflow across several experimental models. The purpose of this study was to determine the therapeutic timing and mechanism of action that underlie Bendavia's cytoprotective property. In rabbits exposed to in vivo ischemia/reperfusion (30/180 min), Bendavia administered 20 minutes prior to reperfusion (0.

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Even though cardiovascular disease is the leading cause of death for men and women, the vast majority of animal studies use male animals. Because female reproductive hormones have been associated with cardioprotective states, many investigators avoid using female animals because these hormones are cyclical and may introduce experimental variability. In addition, no studies have investigated the specific effects of the estrous cycle on cardiac ischemic injury.

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Aims: We have previously shown that exercise leads to sustainable cardioprotection through a mechanism involving improved glutathione replenishment. This study was conducted to determine if redox-dependent modifications in glutathione reductase (GR) were involved in exercise cardioprotection. Furthermore, we sought to determine if reactive oxygen species generated by NADPH oxidase and/or mitochondria during exercise were triggering events for GR modulations.

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Exaggerated pro-inflammatory cytokine production by primed microglia is thought to mediate pathology during stress, aging, and neurodegeneration. Recently, it was demonstrated that beta-adrenergic receptor (β-AR) antagonism prevents priming of microglia in mice exposed to chronic stress. To determine if β-AR stimulation is sufficient to prime microglia, rats were intra-cerebroventricularly administered isoproterenol (β-AR agonist) or vehicle and 24 h later hippocampal microglia were placed in culture with media or LPS.

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A model for characterizing the spectral response of the passband of Wavelength Selective Switches (WSS) is presented. We demonstrate that, in contrast to the commonly used supergaussian model, the presented model offers a more complete match to measured results, as it is based on the physical operation of the optical system. We also demonstrate that this model is better suited for calculation of WSS channel bandwidths, as well as predicting the final bandwidth of cascaded WSS modules.

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