Publications by authors named "John M Gregg"

Placebo and nocebo effects have been well documented for nearly two centuries. However, research has only relatively recently begun to explicate the neurobiological underpinnings of these phenomena. Similarly, research on the broader social implications of placebo/nocebo effects, especially within healthcare delivery settings, is in a nascent stage.

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The endogenous opioid system (EOS) is complex. The line of research contributing to our current body of knowledge about this system is diverse, as are the ways in which endogenous opioids affect human health and behavior. This chapter serves as an introduction to the edited volume.

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Ferroelectric domain walls provide a fertile environment for novel materials physics. If a polarization discontinuity arises, it can drive a redistribution of electronic carriers and changes in band structure, which often result in emergent 2D conductivity. If such a discontinuity is not tolerated, then its amelioration usually involves the formation of complex topological patterns, such as flux-closure domains, dipolar vortices, skyrmions, merons, or Hopfions.

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Following injury to a peripheral nerve, patients may complain of pain over the distribution of the same contralateral nerve, a phenomenon referred to as contralateral pain or mirror pain (MP). Symptoms of MP usually begin after the neuropathic pain from the original nerve injury has become chronic. Chronic neuropathic pain can lead to sensitization and spread of pain.

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Purpose: Obstructive sleep apnea (OSA) increases the risk for insulin resistance (IR). The mechanisms that link the two are not clear and are frequently confounded by obesity. OSA is associated with alterations in adipose-derived hormones (adipokines) that increase IR; however, previous studies have focused on middle-aged and older adults.

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Perovskite phase instability of BiMnO3 has been exploited to synthesize epitaxial metal oxide magnetic nanocrystals. Thin film processing conditions are tuned to promote the breakdown of the perovskite precursor into Bi2O3 matrix and magnetic manganese oxide islands. Subsequent cooling in vacuum ensures complete volatization of the Bi2O3, thus leaving behind an array of self-assembled magnetic Mn3O4 nanostructures.

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Background: Obstructive sleep apnea (OSA) is a disorder characterized by repetitive obstructions of the upper airway. Individuals with OSA experience intermittent hypoxia, hypercapnia, and arousals during sleep, resulting in increased sympathetic activation. Chemoreflex activation, arising from the resultant oscillatory disturbances in blood gases from OSA, exerts control over ventilation, and may induce increases in sympathetic vasoconstriction, contributing to increased long-term risks for hypertension (HTN) and cardiovascular disease (CVD).

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There is growing evidence linking obstructive sleep apnea hypopnea syndrome (OSAHS) with multiple cardiovascular and metabolic diseases. Exercise testing is generally available and routinely used to provide valuable information on cardiopulmonary function in healthy and diseased populations. This review summarizes and integrates recent findings on exercise testing in OSAHS and discusses the potential mechanisms that may contribute to the responses that seem to differentiate these patients from apparently healthy subjects and patients with other cardiopulmonary diseases.

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Study Objective: To evaluate whether cardiovascular responses to maximal exercise testing and recovery are altered with obstructive sleep apnea (OSA) in overweight young adult men.

Design: Three sedentary subject groups were recruited: Overweight with OSA (OSA), overweight without OSA (No-OSA), and normal weight without OSA (Control). Presence of OSA was screened via portable diagnostic device.

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Background: Obstructive sleep apnea (OSA) is characterized by repetitive nighttime obstructions of the upper airway that induce hypoxemia, hypercapnia, sympathetic activation, and arousals. This disorder induces cardiovascular autonomic imbalance and contributes to the development of hypertension. While the diagnostic and prognostic utility of exercise testing is well established in cardiology, the clinical utility of the exercise test in screening for OSA has not been carefully explored.

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Obstructive sleep apnea (OSA) is characterized by repetitive partial and total collapse of the upper airway that induces stressful arousals throughout sleep to reestablish breathing. Although estimates vary, prevalence has been reported as high as 20% in the adult population. OSA is common in several chronic diseases, the most common of which is obesity.

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This paper reviews the behavioral-relaxation treatments of myofascial pain-dysfunction syndrome. The evidence indicates that this pain (located around the oral cavity) is due to muscle hyperactivity, most commonly of the lateral pterygoids. Research concerning relaxation techniques (i.

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The 26 chronic pain patients were tested in a baseline plus cross-over design. Half of the subjects were first treated with high intensity acupuncture; then they were treated with low intensity acupuncture. For the other 13 subjects the treatment order was reversed.

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The submaximal effort tourniquet test has been widely used to evaluate experimental and chronic pain; however, there has been great variation in the manner in which the test has been applied. The present study systemitically evaluates how different levels of exercise duration and effort affect subjects' report of pain. The data indicate the following: (1) the manner in which the exercise is performed has an important effect on subjects' rating of pain, and (2) under all conditions studied, the pain ratings do not increase as a linear function of time.

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Radiofrequency thermoneurolysis (RFTN) was performed in the peripheral infraorbital and inferior alveolar nerves of eight patients with paroxysmal trigeminal neuralgias. Pain severity as measured by tourniquet test and global estimate was significantly reduced in seven of eight patients. The sharp, paroxysmal component of neuralgia was controlled in all seven successes although significant pain was recurring in two patients one year post-operatively.

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A computer-based system to assess and quantify three components of the chronic pain experience is described. The system produces a Pain Profile and classification for each patient based on a mathematical comparison of the pathophysiologic, psychological and behavioral aspects of chronic pain. This computer-based evaluation assists the researcher in analyzing the relative importance of the chronic pain components and helps direct the clinician to the appropriate emphasis of therapy.

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The present study, part of a larger project investigating neurophysiological and psychosocial factors affecting response to acupuncture for chronic pain, compares responders and non-responders to acupuncture on a series of variables assessing personality, affect and stress. Subjects were 40 patients with pain beneath the waist level longer than 6 months duration selected from the roles of the Multidisciplinary Pain Clinic. Responders, defined as 50% or more reduction in pain estimate for greater than two weeks, were found to be less depressed, less passive and overly conventional, have shorter duration of pain, endorse less frequent exposure to stressors, and have less serious non pain-related illnesses.

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Forty patients with chronic pain below the waist level not amenable to conventional medical and/or surgical treatment were randomly assigned to one or two different methods of acupuncture, after studying the underlying pain mechanisms using a Multidisciplinary Pain Clinic approach and the differential spinal block (DSB). One group received acupuncture needling in the classical acupuncture points referred to as meridian loci needling (MLN) and the other group received tender area needling (TAN) with needles inserted in the dermatomal distribution of the painful areas. The responses between the two groups showed no significant difference.

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