Publications by authors named "JR Turner"

Reversing opioid overdoses in rats using a drug that does not enter the brain prevents the sudden and severe withdrawal symptoms associated with therapeutics that target the central nervous system.

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Background: The "loss of control" over drug consumption, present in opioid use disorder (OUD) and known as escalation of intake, is well-established in preclinical rodent models. However, little is known about how antecedent behavioral characteristics, such as valuation of hedonic reinforcers prior to drug use, may impact the trajectory of fentanyl intake over time. Moreover, it is unclear if distinct escalation phenotypes may be driven by genetic markers predictive of OUD susceptibility.

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Article Synopsis
  • - Sepsis leads to increased intestinal permeability, which is linked to higher mortality rates; occludin, a tight junction protein, is crucial for maintaining the intestinal barrier.
  • - Research comparing occludin knockout mice and wild-type controls demonstrated that occludin KOIEC mice experienced significantly increased intestinal permeability only under septic conditions, without changes in other permeability pathways.
  • - The occludin-deficient mice showed elevated inflammatory cytokines and higher mortality rates after sepsis, highlighting occludin's essential role in gut barrier function and survival, suggesting potential therapeutic approaches to enhance occludin function in sepsis treatment.
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Introduction: Views of aging have been linked with many important outcomes in older adults. Subjective cognition, or one's perception of their cognitive functioning, may be a valuable indicator of cognitive changes as individuals age, but is known to be impacted by a variety of factors. The aim of this systematic review was to synthesize the evidence on relationships between views of aging and subjective cognition, including whether and how these relationships may differ based on age.

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Purpose Of Review: The contributions of intestinal barrier loss, that is, increased permeability, to multiple disorders, including inflammatory bowel disease (IBD), have been a topic of speculation for many years, and the literature is replete with conclusions based on correlation and speculation. The goal of this article is to critically review recent advances in mechanistic understanding of barrier regulation and the evidence for and against contributions of intestinal barrier loss to disease pathogenesis.

Recent Findings: It is now recognized that intestinal permeability reflects the combined effects of two distinct routes across tight junctions, which form selectively permeable seals between adjacent epithelial cells, and mucosal damage that leads to nonselective barrier loss.

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Background: Chronic cigarette smokers report withdrawal symptomology, including affective dysfunction and cognitive deficits. While there are studies demonstrating sex specific withdrawal symptomology in nicotine-dependent individuals, literature examining the underlying biological mediators of this is scant and not in complete agreement. Therefore, in this study, we evaluated the sex specific effects of nicotine and withdrawal on contextual fear memory, a hippocampally dependent aspect of cognition that is disrupted in nicotine withdrawal.

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We report the measurement of impulsive stimulated x-ray Raman scattering in neutral liquid water. An attosecond pulse drives the excitations of an electronic wavepacket in water molecules. The process comprises two steps: a transition to core-excited states near the oxygen atoms accompanied by transition to valence-excited states.

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Article Synopsis
  • Macrophage-driven inflammation plays a role in metabolic dysfunction-associated steatohepatitis (MASH), but how macrophage activation is regulated is still not well understood.* -
  • Beta-arrestin 2, a protein found in macrophages, was found to be elevated in patients with MASH compared to healthy individuals, linking it to the severity of liver disease.* -
  • In studies with mice, removing beta-arrestin 2 prevented MASH development, suggesting that targeting this protein could be a potential treatment strategy for the condition.*
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Recent evidence indicates that neuronal activity within the claustrum (CLA) may be central to cellular and behavioral responses to psychedelic hallucinogens. The CLA prominently innervates many cortical targets and displays exceptionally high levels of serotonin (5-HT) binding. However, the influence of serotonin receptors, prime targets of psychedelic drug action, on CLA activity remains unexplored.

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This study assessed the ability of α and α-adrenergic drugs to decrease fentanyl-induced locomotor and ventilatory depression. Rats were given saline or fentanyl, followed by: (1) naltrexone, (2) naloxone, (3) nalmefene, (4) α agonist phenylephrine, (5) α antagonist prazosin, (6) α antagonist BMY-7378, (7) α agonist clonidine, (8) α antagonist yohimbine or (9) vehicle. All µ-opioid antagonists dose-dependently reversed fentanyl-induced locomotor and ventilatory depression.

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Background And Objectives: Although prior research has shown that social relationships and daily stress are strongly associated with cognitive function, few studies have explored the link between the quality of daily social encounters and subjective cognitive decline (SCD). The present study explores whether the quality of older adults' daily social encounters is associated with SCD through daily stress.

Research Design And Methods: This study used data from 254 adults aged 70 or older (  = 76.

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While in the process of designing more effective synthetic opioid rescue agents, we serendipitously identified a new chemotype of potent synthetic opioid. Here, we report that conformational constraint of a piperazine ring converts a mu opioid receptor (MOR) antagonist into a potent MOR agonist. The prototype of the series, which we have termed atoxifent (), possesses potent in vitro agonist activity.

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Preclinical human inflammatory bowel disease (IBD) mechanisms is one of 5 focus areas of the Challenges in IBD Research 2024 document, which also includes environmental triggers, novel technologies, precision medicine, and pragmatic clinical research. Herein, we provide a comprehensive overview of current gaps in inflammatory bowel diseases research that relate to preclinical research and deliver actionable approaches to address them with a focus on how these gaps can lead to advancements in IBD interception, remission, and restoration. The document is the result of multidisciplinary input from scientists, clinicians, patients, and funders and represents a valuable resource for patient-centric research prioritization.

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Article Synopsis
  • - Tight junctions (TJs) are specialized connections between cells in epithelial and endothelial tissues, creating selective barriers that help maintain different fluid environments in the body.
  • - The development of TJs has been crucial in evolution, enabling the existence of multicompartmental organisms and effective barrier-forming tissues.
  • - This Perspective discusses the advances made in understanding TJs over the past sixty years, focusing on their structure, function, and regulation, while also addressing future research challenges.
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Background & Aims: Humans with WNT2B deficiency have severe intestinal disease, including significant inflammatory injury, highlighting a critical role for WNT2B. We sought to understand how WNT2B contributes to intestinal homeostasis.

Methods: We investigated the intestinal health of Wnt2b knock out (KO) mice.

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Background & Aims: Lacticaseibacillus rhamnosus GG (LGG) is the world's most consumed probiotic but its mechanism of action on intestinal permeability and differentiation along with its interactions with an essential source of signaling metabolites, dietary tryptophan (trp), are unclear.

Methods: Untargeted metabolomic and transcriptomic analyses were performed in LGG monocolonized germ-free mice fed trp-free or -sufficient diets. LGG-derived metabolites were profiled in vitro under anaerobic and aerobic conditions.

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Global ground-level measurements of elements in ambient particulate matter (PM) can provide valuable information to understand the distribution of dust and trace elements, assess health impacts, and investigate emission sources. We use X-ray fluorescence spectroscopy to characterize the elemental composition of PM samples collected from 27 globally distributed sites in the Surface PARTiculate mAtter Network (SPARTAN) over 2019-2023. Consistent protocols are applied to collect all samples and analyze them at one central laboratory, which facilitates comparison across different sites.

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Coral reefs are increasingly impacted by climate-induced warming events. However, there is limited empirical evidence on the variation in the response of shallow coral reef communities to thermal stress across depths. Here, we assess depth-dependent changes in coral reef benthic communities following successive marine heatwaves from 2015 to 2017 across a 5-25 m depth gradient in the remote Chagos Archipelago, Central Indian Ocean.

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Nicotine use disorder remains a major public health emergency despite years of trumpeting the consequences of smoking. This is likely due to the complex interplay of genetics and nicotine exposure across the lifespan of these individuals. Genetics influence all aspects of life, including complex disorders such as nicotine use disorder.

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Article Synopsis
  • Intestinal expression of claudin-2, a tight junction protein, is linked to increased permeability and is significantly upregulated in septic patients and mice.
  • In experiments with claudin-2 knockout mice, the absence of this protein led to reduced inflammation, lower immune cell counts, and decreased intestinal damage during sepsis.
  • Deleting claudin-2 not only improved survival rates in septic mice but also mitigated harmful microbial changes, indicating its potential as a therapeutic target in treating septic patients.
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Background: Smoking is the largest preventable cause of death and disease in the United States, with <5% of quit attempts being successful. Microglia activation and proinflammatory neuroimmune signaling in reward neurocircuitry are implicated in nicotine withdrawal symptomology. Microglia are integral regulators of blood-brain barrier (BBB) functionality as well; however, whether the effects of nicotine withdrawal on microglia function impact BBB integrity is unknown.

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Tobacco smoking remains a leading cause of preventable death in the United States, with approximately a 5% success rate for smokers attempting to quit. High relapse rates have been linked to several genetic factors, indicating that the mechanistic relationship between genes and drugs of abuse is a valuable avenue for the development of novel smoking cessation therapies. For example, various single nucleotide polymorphisms (SNPs) in the gene for neuregulin 3 (NRG3) and its cognate receptor, the receptor tyrosine-protein kinase erbB-4 (ERBB4), have been linked to nicotine addiction.

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Intestinal epithelia express two long myosin light-chain kinase (MLCK) splice variants, MLCK1 and MLCK2, which differ by the absence of a complete immunoglobulin (Ig)-like domain 3 within MLCK2. MLCK1 is preferentially associated with the perijunctional actomyosin ring at steady state, and this localization is enhanced by inflammatory stimuli including tumor necrosis factor (TNF). Here, we sought to identify MLCK1 domains that direct perijunctional MLCK1 localization and their relevance to disease.

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