Publications by authors named "William Rea"

Ménière's disease is a disabling condition causing vertigo and hearing loss yet remains incompletely understood. Registry studies have the potential to answer important questions about phenotypes and natural history of clinical conditions. The aim of this study was to explore the feasibility of a patient-centered national Ménière's disease registry.

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  • (R,S)-methadone consists of two enantiomers, (R)-MTD and (S)-MTD, both of which interact with µ-opioid receptors (MORs) to provide pain relief but have different effects on the brain's reward system.
  • (S)-MTD is being researched as an antidepressant due to its unique properties; it does not increase dopamine levels or cause locomotor stimulation like (R)-MTD, and it weakly reinforces reward pathways.
  • Additionally, (S)-MTD acts as a partial agonist at MORs and specifically inhibits the MOR-GalR heteromer, which may lower the risk of dependence compared to traditional opioids.
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  • (R,S)-methadone (MTD) is a combination of two enantiomers, (R)-MTD and (S)-MTD, used to treat opioid use disorder (OUD) and pain, with (R)-MTD being the effective treatment for OUD.
  • Research showed that (S)-MTD, while developing as an antidepressant, does not act on N-methyl-D-aspartate receptors (NMDARs) as previously thought but instead shows similar efficacy to (R)-MTD at mu-opioid receptors (MORs).
  • (S)-MTD has a lower potential for abuse, does not self-administer, and uniquely interacts with receptors, providing insights into its distinct
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  • The study explores how dopamine D1 and D2 receptor (DR-DR) heteromers can influence the effects of selective dopamine ligands, suggesting their relevance as drug development targets.
  • Researchers demonstrated that three similar dopamine ligands (PG01042, PG01037, and VK4-116) have distinct effects based on DR-DR heteromerization, showing varying roles in signaling.
  • The findings indicate that GPCR heteromers should be considered key targets for drug development, especially for conditions like L-DOPA-induced dyskinesia in Parkinson's disease, rather than focusing solely on individual GPCR components.
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  • Ghrelin receptors (GHS-R1a and GHS-R1b) interact in a complex way, with GHS-R1b not directly binding ghrelin but influencing GHS-R1a’s function and pharmacological properties.
  • Research indicates that GHS-R1a specifically forms oligomers with D5R in the ventral tegmental area (VTA) of the brain, which shows different signaling characteristics than oligomers with D1R, suggesting unique roles for these complexes.
  • Experimental evidence highlights that GHS-R1a:GHS-R1b:D1R oligomers are crucial for mediating the effects of ghrelin on dopaminergic signaling and motivated behavior in rodents, emphasizing the
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Aims: Currently, there is a growing body of research demonstrating that spin - the misinterpretation and distortion of a study's findings - is common in different fields of medicine. To our knowledge, no study has investigated its presence in systematic reviews focused on diabetic therapies.

Methods: We performed a cross-sectional study by searching MEDLINE and Embase for systematic reviews focused on pharmacologic treatments for type 2 diabetes mellitus.

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Akathisia is an urgent need to move that is associated with treatment with dopamine receptor blocking agents (DRBAs) and with restless legs syndrome (RLS). The pathogenetic mechanism of akathisia has not been resolved. This article proposes that it involves an increased presynaptic dopaminergic transmission in the ventral striatum and concomitant strong activation of postsynaptic dopamine D receptors, which form complexes (heteromers) with dopamine D and adenosine A receptors.

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Our working hypothesis is that a hypoadenosinergic state is a main pathogenetic factor that determines the sensory-motor symptoms and hyperarousal of restless legs syndrome (RLS). We have recently demonstrated that brain iron deficiency (BID) in rodents, a well-accepted animal model of RLS, is associated with a generalized downregulation of adenosine A receptors (A1R) in the brain and with hypersensitivity of corticostriatal glutamatergic terminals. Here, we first review the experimental evidence for a pivotal role of adenosine and A1R in the control of striatal glutamatergic transmission and the rationale for targeting putative downregulated striatal A1R in RLS patients, which is supported by recent clinical results obtained with dipyridamole, an inhibitor of the nucleoside transporters ENT1 and ENT2.

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Several studies found in vitro evidence for heteromerization of dopamine D receptors (D1R) and D receptors (D3R), and it has been postulated that functional D1R-D3R heteromers that are normally present in the ventral striatum mediate synergistic locomotor-activating effects of D1R and D3R agonists in rodents. Based also on results obtained in vitro, with mammalian transfected cells, it has been hypothesized that those behavioral effects depend on a D1R-D3R heteromer-mediated G protein-independent signaling. Here, we demonstrate the presence on D1R-D3R heteromers in the mouse ventral striatum by using a synthetic peptide that selectively destabilizes D1R-D3R heteromers.

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Identifying non-addictive opioid medications is a high priority in medical sciences, but μ-opioid receptors mediate both the analgesic and addictive effects of opioids. We found a significant pharmacodynamic difference between morphine and methadone that is determined entirely by heteromerization of μ-opioid receptors with galanin Gal1 receptors, rendering a profound decrease in the potency of methadone. This was explained by methadone's weaker proficiency to activate the dopaminergic system as compared to morphine and predicted a dissociation of therapeutic versus euphoric effects of methadone, which was corroborated by a significantly lower incidence of self-report of "high" in methadone-maintained patients.

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Huntington's disease (HD) is a hereditary neurodegenerative disorder caused by a mutation in the IT15 gene that encodes for the huntingtin protein. Mutated hungtingtin, although widely expressed in the brain, predominantly affects striato-pallidal neurons, particularly enriched with adenosine A receptors (AR), suggesting a possible involvement of adenosine and AR is the pathogenesis of HD. In fact, polymorphic variation in the gene influences the age at onset in HD, and AR dynamics is altered by mutated huntingtin.

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Purpose: The goal of this study was to present the results of treatment of 100 chemically sensitive and chronically mold-exposed patients, who continued to be disabled even after decontamination of their houses or work places or they were physically removed from their sources of mold.

Methods: Molds were identified, serum anti-mold immunoglobulin G antibodies were measured, patients were skin-tested, immunologic abnormalities were recorded, and objective neurologic tests were performed in a subset of patients.

Findings: Patient sensitivities and exposures were confirmed by measuring serum immunoglobulin G anti-mold antibodies, intradermal skin testing, and trichothecene toxin breakdown products in the urine.

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The two highly homologous subtypes of stimulatory G proteins Gαs (Gs) and Gαolf (Golf) display contrasting expression patterns in the brain. Golf is predominant in the striatum, while Gs is predominant in the cortex. Yet, little is known about their functional distinctions.

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The symptomatology of Restless Legs Syndrome (RLS) includes periodic leg movements during sleep (PLMS), dysesthesias, and hyperarousal. Alterations in the dopaminergic system, a presynaptic hyperdopaminergic state, seem to be involved in PLMS, while alterations in glutamatergic neurotransmission, a presynaptic hyperglutamatergic state, seem to be involved in hyperarousal and also PLMS. Brain iron deficiency (BID) is well-recognized as a main initial pathophysiological mechanism of RLS.

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Objective: The first aim was to demonstrate a previously hypothesized increased sensitivity of corticostriatal glutamatergic terminals in the rodent with brain iron deficiency (BID), a pathogenetic model of restless legs syndrome (RLS). The second aim was to determine whether these putative hypersensitive terminals could constitute a significant target for drugs effective in RLS, including dopamine agonists (pramipexole and ropinirole) and α δ ligands (gabapentin).

Methods: A recently introduced in vivo optogenetic-microdialysis approach was used, which allows the measurement of the extracellular concentration of glutamate upon local light-induced stimulation of corticostriatal glutamatergic terminals.

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Opioid use during pregnancy poses serious risks for the mother and the unborn child. Opioid-use disorder may be managed with medication-assisted treatment (MAT) in an outpatient setting, but few MAT practices specifically address the challenges faced by pregnant women. This article describes a medical office-based educational support group for women in MAT for opioid-use disorder who were pregnant and/or parenting young children.

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Unlabelled: The neuropeptide galanin has been shown to interact with the opioid system. More specifically, galanin counteracts the behavioral effects of the systemic administration of μ-opioid receptor (MOR) agonists. Yet the mechanism responsible for this galanin-opioid interaction has remained elusive.

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The initial goal of this study was to investigate alterations in adenosine A receptor (AR) density or function in a rat model of Huntington disease (HD) with reported insensitivity to an AR antagonist. Unsuspected negative results led to the hypothesis of a low striatal adenosine tone and to the search for the mechanisms involved. Extracellular striatal concentrations of adenosine were measured with in vivo microdialysis in two rodent models of early neuropathological stages of HD disease, the Tg51 rat and the zQ175 knock-in mouse.

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Histories of mold, pollen, dust, food, chemicals, and electromagnetic field (EMF) sensitivities are the major categories of triggers for chemical sensitivity. They are tied together by the coherence phenomenon, where each has its own frequencies and identifiable EMF; therefore, they can be correlated. The diagnosis of chemical sensitivity can be done accurately in a less-polluted, controlled environment, as was done in these studies.

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It is generally assumed that infralimbic cortex (ILC) and prelimbic cortex, two adjacent areas of the medial prefrontal cortex (mPFC) in rodents, provide selective excitatory glutamatergic inputs to the nucleus accumbens (NAc) shell and core, respectively. It is also generally believed that mPFC influences the extracellular levels of dopamine in the NAc primarily by an excitatory collateral to the ventral tegmental area (VTA). In the present study, we first established the existence of a selective functional connection between ILC and the posteromedial portions of the VTA (pmVTA) and the mNAc shell (pmNAc shell), by measuring striatal neuronal activation (immunohistochemical analysis of ERK1/2 phosphorylation) and glutamate release (in vivo microdialysis) upon ILC electrical stimulation.

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Adenosine A2A receptor (A2AR)-dopamine D2 receptor (D2R) heteromers are key modulators of striatal neuronal function. It has been suggested that the psychostimulant effects of caffeine depend on its ability to block an allosteric modulation within the A2AR-D2R heteromer, by which adenosine decreases the affinity and intrinsic efficacy of dopamine at the D2R. We describe novel unsuspected allosteric mechanisms within the heteromer by which not only A2AR agonists, but also A2AR antagonists, decrease the affinity and intrinsic efficacy of D2R agonists and the affinity of D2R antagonists.

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Unlabelled: CONTEXT : Terpenes and terpenoids are a diverse class of organic compounds produced by a variety of plants, particularly conifers. Chemically sensitive patients can be targeted by terpenes and terpenoids, resulting in a triggering of symptoms and pathology. Often patients cannot clear their symptoms from exposure to chemicals unless terpenes and terpenoids are avoided and neutralized along with chemical avoidance and treatment.

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Manganese-enhanced magnetic resonance imaging (MEMRI) is a powerful technique for assessing the functional connectivity of neurons within the central nervous system. Despite the widely held proposition that MEMRI signal is dependent on neuronal activity, few studies have directly tested this implicit hypothesis. In the present series of experiments, MnCl2 was injected into the habenula of urethane-anesthetized rats alone or in combination with drugs known to alter neuronal activity by modulating specific voltage- and/or ligand-gated ion channels.

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