Publications by authors named "Michael D Weber"

Purpose: Pharmacologic therapies for neurofibromatosis type 1-associated plexiform neurofibromas (NF1-PNs) are limited; currently, none are US Food and Drug Administration-approved for adults.

Methods: ReNeu is an open-label, multicenter, pivotal, phase IIb trial of mirdametinib in 58 adults (≥18 years of age) and 56 children (2 to 17 years of age) with NF1-PN causing significant morbidities. Patients received mirdametinib capsules or tablets for oral suspension (2 mg/m twice daily, maximum 4 mg twice daily), regardless of food intake, in 3 weeks on/1 week off 28-day cycles.

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Traumatic injury in children is known to cause immune suppression. Polytrauma involving a traumatic brain injury (TBI) may increase this degree of immune suppression, which increases the risk of developing nosocomial infections, potentially causing secondary brain injury and worsening patient outcomes. Despite the high prevalence of polytrauma with TBI in children, mechanisms of immune suppression following such injuries remain poorly understood.

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Clinical studies indicate that psychosocial stress contributes to adverse chronic pain outcomes in patients, but it is unclear how this is initiated or amplified by stress. Repeated social defeat (RSD) is a mouse model of psychosocial stress that activates microglia, increases neuroinflammatory signaling, and augments pain and anxiety-like behaviors. We hypothesized that activated microglia within the spinal cord facilitate increased pain sensitivity following RSD.

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Article Synopsis
  • - The study investigates how repeated social defeat (RSD) stress in mice affects the brain's immune response, especially focusing on the role of microglia and their impact on anxiety and depression.
  • - Results showed that microglia retain altered activity long after RSD, and their elimination prevented monocyte accumulation and anxiety recurrence when exposed to acute stress.
  • - However, microglial elimination did not affect neuronal sensitization, indicating that neurons also remain sensitized after RSD, which contributes to prolonged immune reactions and sickness behavior.
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Background: Raltegravir (RTG) and dolutegravir (DTG) have different pharmacokinetic patterns in the gastrointestinal tract. To determine if this results in pharmacodynamic differences, we compared HIV RNA, HIV DNA and immunological markers in gut-associated lymphoid tissue (GALT) of HIV-infected participants receiving RTG or DTG with tenofovir+emtricitabine (TDF/FTC).

Methods: GALT specimens from the terminal ileum, splenic flexure and rectum were obtained by colonoscopy at a single time point in 20 adults treated with RTG (n=10) or DTG (n=10) with HIV RNA <50 copies/ml.

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Objective: Mounting evidence indicates that stress influences the experience of pain. Exposure to psychosocial stress disrupts bi-directional communication pathways between the central nervous system and peripheral immune system, and can exacerbate the frequency and severity of pain experienced by stressed subjects. Repeated social defeat (RSD) is a murine model of psychosocial stress that recapitulates the immune and behavioral responses to stress observed in humans, including activation of stress-reactive neurocircuitry and increased pro-inflammatory cytokine production.

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We report on the benefits of changing the bridging group X of bis-pyridyl ligands, that is, Py-X-Py where X is NH, CH , C(CH ) , or PPh, on the photo- and electroluminescent properties of a new family of luminescent cationic H-heterocyclic carbene (NHC) copper(I) complexes. A joint experimental and theoretical study demonstrates that the bridging group affects the molecular conformation from a planar-like structure (X is NH and CH ) to a boat-like structure (X is C(CH ) and PPh), leading to i) four-fold enhancement of the photoluminescence quantum yield (ϕ ) without affecting the thermally activated delayed fluorescence mechanism, and ii) one order of magnitude reduction of the ionic conductivity (σ) of thin films. This leads to an overall enhancement of the device efficacy and luminance owing to the increased ϕ and the use of low applied driving currents.

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This work studies the effect of the σ-Hammett parameter (σ) - i.e., the σ-donation effect caused by substitution at the para position of a bipyridine ligand (4,4'-Rbipy, where R is MeO, Me, H, NO) - on both the photo- and electro-luminescence features of a series of heteroleptic copper(i) complexes - i.

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Stress and glucocorticoids (GCs) have universally been considered to be anti-inflammatory, however in recent years, stress and GCs have been found to exert permissive effects (immunological priming) on neuroinflammatory processes. This phenomenon of priming is characterized by prior stress or GC exposure potentiating the neuroinflammatory response to a subsequent immune challenge. A considerable body of evidence is discussed here that supports this permissive effect of stress and GCs.

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The impact of the foods we eat on metabolism and cardiac physiology has been studied for decades, yet less is known about the effects of foods on the CNS, or the behavioral manifestations that may result from these effects. Previous studies have shown that long-term consumption of high-fat foods leading to diet-induced obesity sensitizes the inflammatory response of the brain to subsequent challenging stimuli, causing deficits in the formation of long-term memories. The new findings reported here demonstrate that short-term consumption of a high-fat diet (HFD) produces the same outcomes, thus allowing the examination of mechanisms involved in this process long before obesity and associated comorbidities occur.

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Unlabelled: Amplified neuroinflammatory responses following an immune challenge occur with normal aging and can elicit or exacerbate neuropathology. The mechanisms mediating this sensitized or "primed" immune response in the aged brain are not fully understood. The alarmin high mobility group box 1 (HMGB1) can be released under chronic pathological conditions and initiate inflammatory cascades.

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The syntheses, photophysical/electrochemical characterizations of different metallated porphyrins -i.e., Zn(2+), Pt(2+), Pd(2+), and Sn(4+) porphyrins - as well as their first application in light-emitting electrochemical cells are provided.

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Mounting evidence indicates that proinflammatory signaling in the brain affects mood, cognition, and behavior and is linked with the etiology of psychiatric disorders, including anxiety and depression. The purpose of this review is to focus on stress-induced bidirectional communication pathways between the central nervous system (CNS) and peripheral immune system that converge to promote a heightened neuroinflammatory environment. These communication pathways involve sympathetic outflow from the brain to the peripheral immune system that biases hematopoietic stem cells to differentiate into a glucocorticoid-resistant and primed myeloid lineage immune cell.

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This study presents the influence of various substituents on the photophysical features of heteroleptic copper(I) complexes bearing both N-heterocyclic carbene (NHC) and dipyridylamine (dpa = dipyridylamine skeleton corresponding to ligand L1) ligands. The luminescent properties have been compared to our recently reported archetypal blue emitting [Cu(IPr)(dpa)][PF6] complex. The choice of the substituents on both ligands has been guided to explore the effect of the electron donor/acceptor and "push-pull" on the emission wavelengths and photoluminescence quantum yields.

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This work provides the synthesis, structural characterization, electrochemical and photophysical features, as well as the application in light-emitting electrochemical cells (LECs) of a novel heteroleptic copper(i) complex - [Cu(impy)(POP)][PF6], where impy is 3-(2-methoxyphenyl)-1-(pyridine-2-yl)imidazo[1,5-a]pyridine and POP is bis{2-(diphenylphosphanyl)phenyl}ether. This compound shows blue photoluminescence (PL, λ = 450 nm) in solution and solid-state and excellent redox stability. Despite these excellent features, the electroluminescence (EL) response is located at ∼550 nm.

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We report two unprecedent alkynyl bridging cyclometalated clusters [Ir2M2(ppy)4(μ-C[triple bond, length as m-dash]CC6H4-OMe3)4] where M is Ag (2) and Cu (3), which display distinctive luminescence properties. While 2 features a green phosphorescence/electroluminescence nature located at the ppy ligands ((3)LC), 3 shows an orange emission confined to the metals and alkynyl groups having a mixed (3)L'C/(3)L'MCT/(3)MMCT (L' = alkynyl) nature.

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Circadian rhythms are endogenous cycles of physiology and behavior that align with the daily rotation of the planet and resulting light-dark cycle. The circadian system ensures homeostatic balance and regulates many aspects of physiology, including the stress response and susceptibility to and/or severity of stress-related sequelae. Both acute and chronic stressors amplify neuroinflammatory responses to a subsequent immune challenge, however it is not known whether circadian timing of the stressor regulates the priming response.

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The alarmin high mobility group box-1 (HMGB1) has been implicated as a key factor mediating neuroinflammatory processes. Recent findings suggest that the redox state of HMGB1 is a critical molecular feature of HMGB1 such that the reduced form (fr-HMGB1) is chemotactic, while the disulfide form (ds-HMGB1) is pro-inflammatory. The present study examined the neuroinflammatory effects of these molecular forms as well as the ability of these forms to prime the neuroinflammatory and microglial response to an immune challenge.

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The first bioinspired hybrid white-light-emitting diodes (bio-HLEDs) featuring protein cascade coatings are presented. For easy fabrication a new strategy to stabilize proteins in rubber-like material was developed. The synergy between the excellent features of fluorescent proteins and the easily processed rubber produces bio-HLEDs with less than 10% loss in luminous efficiency over 100 hours.

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Methamphetamine (METH) induces neuroinflammatory effects, which may contribute to the neurotoxicity of METH. However, the mechanism by which METH induces neuroinflammation has yet to be clarified. A considerable body of evidence suggests that METH induces cellular damage and distress, particularly in dopaminergic neurons.

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Background: Prior exposure to stress is a risk factor for developing posttraumatic stress disorder (PTSD) in response to trauma, yet the mechanisms by which this occurs are unclear. Using a rodent model of stress-based susceptibility to PTSD, we investigated the role of serotonin in this phenomenon.

Methods: Adult mice were exposed to repeated immobilization stress or handling, and the role of serotonin in subsequent fear learning was assessed using pharmacologic manipulation and western blot detection of serotonin receptors, measurements of serotonin, high-speed optogenetic silencing, and behavior.

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High mobility group box-1 (HMGB1) is an endogenous danger signal or alarmin that mediates activation of the innate immune response including chemotaxis and pro-inflammatory cytokine release. HMGB1 has been implicated in the pathophysiology of several neuroinflammatory conditions including ischemia, traumatic brain injury, seizure and chronic ethanol use. In the present review, the unique structural and functional properties of HMGB1 will be explored including its affinity for multiple pattern recognition receptors (TLR2/TLR4), redox sensitivity and adjuvant-like properties.

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Exposure to acute and chronic stressors sensitizes the proinflammatory response of microglia to a subsequent immune challenge. However, the proximal signal by which stressors prime microglia remains unclear. Here, high mobility group box-1 (HMGB-1) protein was explored as a potential mediator of stress-induced microglial priming and whether HMGB-1 does so via the nucleotide-binding domain, leucine-rich repeat, pyrin domain containing protein 3 (NLRP3) inflammasome.

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High-fat diet (HFD)-induced obesity is reaching worldwide proportions. In addition to causing obesity, HFDs also induce a variety of health disorders, which includes cognitive decline. Hippocampal function may be particularly vulnerable to the negative consequences of HFD, and it is suspected that 'primed' neuroinflammatory processes may mediate this response.

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Chronic stress as well as chronic treatment with glucocorticoids (GCs) primes the neuroinflammatory response to a subsequent pro-inflammatory challenge. However, it remains unclear whether chronic GCs sensitize the response of key CNS immune substrates (i.e.

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