Publications by authors named "Kevin Walton"

The smoking rate is high in patients with schizophrenia. Brain stimulation targeting conventional brain circuits associated with nicotine addiction has also yielded mixed results. We aimed to identify alternative circuitries associated with nicotine addiction in both the general population and schizophrenia, and then test whether modulation of such circuitries may alter nicotine addiction behaviors in schizophrenia.

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Background: Opioid Use Disorder (OUD) is an escalating public health problem with over 100,000 drug overdose-related deaths last year most of them related to opioid overdose, yet treatment options remain limited. Non-invasive Vagal Nerve Stimulation (nVNS) can be delivered via the ear or the neck and is a non-medication alternative to treatment of opioid withdrawal and OUD with potentially widespread applications.

Methods: This paper reviews the neurobiology of opioid withdrawal and OUD and the emerging literature of nVNS for the application of OUD.

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Adherence is a critical mediator of treatment outcome across health conditions and low rates of adherence undermine success in smoking cessation treatment. This narrative review provides an overview of different techniques that can be used to measure adherence to smoking cessation treatments and outlines strategies to address treatment adherence. Techniques to measure adherence include conducting pill counts, collecting self-reports of adherence, directly observed therapy, biochemical verification methods, and electronic data collection via medication events monitoring systems.

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Treating opioid use disorder (OUD) is a significant healthcare challenge in the United States. Remaining abstinent from opioids is challenging for individuals with OUD due to withdrawal symptoms that include restlessness. However, to our knowledge, studies of acute withdrawal have not quantified restlessness using involuntary movements.

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Background: Opioid Use Disorder (OUD) is a serious public health problem, and the behavioral and physiological effects of opioid withdrawal can be a major impediment to recovery. Medication for OUD is currently the mainstay of treatment; however, it has limitations and alternative approaches are needed.

Objective: The purpose of this study was to assess the effects of transcutaneous cervical vagus nerve stimulation (tcVNS) on behavioral and physiological manifestations of acute opioid withdrawal.

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Assessing tobacco use intensity allows researchers to examine tobacco use in greater detail than assessing ever or current use only. Tobacco use intensity measures have been developed that are specific to tobacco products, such as asking smokers to report number of cigarettes smoked per day. However, consensus on electronic cigarette use intensity measures that can be used for survey research has yet to be established due to electronic cigarette product and user behavior heterogeneity.

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Background: Electronic cigarettes (e-cigarettes) represent an emerging public health issue. These devices deliver nicotine along with other constituents, including flavorants, via an inhalable aerosol. Their uptake is rapidly increasing in both adults and youths, primarily among current smokers.

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Casein kinase 1 delta (CK1δ) and casein kinase 1 epsilon (CK1ε) inhibitors are potential therapeutic agents for a range of psychiatric disorders. The feasibility of developing a CNS kinase inhibitor has been limited by an inability to identify safe brain-penetrant compounds with high kinome selectivity. Guided by structure-based drug design, potent and selective CK1δ/ε inhibitors have now been identified that address this gap, through the design and synthesis of novel 4-[4-(4-fluorophenyl)-1-(piperidin-4-yl)-1H-imidazol-5-yl]pyrimidin-2-amine derivatives.

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Casein kinase 1δ (CK1δ) and 1ε (CK1ε) are believed to be necessary enzymes for the regulation of circadian rhythms in all mammals. On the basis of our previously published work demonstrating a CK1ε-preferring compound to be an ineffective circadian clock modulator, we have synthesized a series of pyrazole-substitued pyridine inhibitors, selective for the CK1δ isoform. Additionally, using structure-based drug design, we have been able to exploit differences in the hinge region between CK1δ and p38 to find selective inhibitors that have minimal p38 activity.

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Circadian pacemaking requires the orderly synthesis, posttranslational modification, and degradation of clock proteins. In mammals, mutations in casein kinase 1 (CK1) epsilon or delta can alter the circadian period, but the particular functions of the WT isoforms within the pacemaker remain unclear. We selectively targeted WT CK1epsilon and CK1delta using pharmacological inhibitors (PF-4800567 and PF-670462, respectively) alongside genetic knockout and knockdown to reveal that CK1 activity is essential to molecular pacemaking.

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The circadian clock links our daily cycles of sleep and activity to the external environment. Deregulation of the clock is implicated in a number of human disorders, including depression, seasonal affective disorder, and metabolic disorders. Casein kinase 1 epsilon (CK1epsilon) and casein kinase 1 delta (CK1delta) are closely related Ser-Thr protein kinases that serve as key clock regulators as demonstrated by mammalian mutations in each that dramatically alter the circadian period.

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The peptide galanin is primarily expressed in the central nervous system (CNS) and it is active in a range of models of behavior. The identification of three galanin receptors, whose distribution of expression is distinct but overlapping, is evidence of the complexity of galanin's regulation of neuronal function. The majority of studies examining galanin have used broad methods to identify its function, employing nonselective peptide agonists and antagonists, or transgenic animal models.

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