Reply to Zaman et al.
No abstract available (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

About the limits of mediation analyses in solving chicken-vs-egg—like type of questions
No abstract available (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Reply to Martin-Saavedra and Saade-Lemus
No abstract available (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Music's objective classification improves quality of music-induced analgesia studies
No abstract available (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Pain or nociception? Subjective experience mediates the effects of acute noxious heat on autonomic responses - corrected and republished
Nociception reliably elicits an autonomic nervous system (ANS) response. Because pain and ANS circuitry interact on multiple spinal, subcortical, and cortical levels, it remains unclear whether autonomic responses are simply a reflexive product of noxious stimulation regardless of how stimulation is consciously perceived or whether the experience of pain mediates ANS responses to noxious stimulation. To test these alternative predictions, we examined the relative contribution of noxious stimulation and individual pain experience to ANS responses in healthy volunteers who underwent 1 or 2 pain assessment tasks. Participants...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Corrected and Republished Article Source Type: research

Cisplatin educates CD8+ T cells to prevent and resolve chemotherapy-induced peripheral neuropathy in mice
In conclusion, resolution of CIPN requires in vivo education of CD8+ T cells by exposure to cisplatin. Future studies should examine whether ex vivo CD8+ T cell education could be applied as a therapeutic strategy for treating or preventing CIPN in patients. (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

α5GABAA receptors play a pronociceptive role and avoid the rate-dependent depression of the Hoffmann reflex in diabetic neuropathic pain and reduce primary afferent excitability
Diabetic neuropathy is an incapacitating complication in diabetic patients. The cellular and molecular mechanisms involved in this pathology are poorly understood. Previous studies have suggested that the loss of spinal GABAergic inhibition participate in painful diabetic neuropathy. However, the role of extrasynaptic α5 subunit-containing GABAA (α5GABAA) receptors in this process is not known. The purpose of this study was to investigate the role of α5GABAA receptors in diabetes-induced tactile allodynia, loss of rate-dependent depression (RDD) of the Hoffmann reflex (HR), and modulation of primary affer...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Distal infraorbital nerve injury: a model for persistent facial pain in mice
This study characterizes the impact of a distal infraorbital nerve injury, called DIONI, which consists of ligature and transection of distal fibers of the infraorbital nerve. We assessed nociception using a conflict paradigm and optogenetics, and a set of reward, aversion, spatial, temporal, and competition tasks in the IntelliCage to study multiple aspects of cognition, circadian rhythms, and social interactions in groups of mice in home cage environments. Mice with DIONI developed cold and mechanical allodynia, and hypersensitivity towards blue light stimulation. They maintained a long-lasting memory of aversive stimuli...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Experimental evaluation of central pain processes in young women with primary dysmenorrhea
Primary dysmenorrhea (PD; menstrual pain without an underlying medical condition) is associated with enhanced pain sensitivity and temporal summation (TS) in adult women, which may reflect the presence of central pain processes. Research in this area has been limited by focusing on only adult populations and incomplete assessments of central sensitization. The current study explored both excitatory and inhibitory measures of pain processing in girls and young adult women with and without PD. Thirty-two young women with PD and 34 healthy controls underwent laboratory pain testing during each of 3 menstrual cycle phases (men...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Multicolumn spinal cord stimulation for predominant back pain in failed back surgery syndrome patients: a multicenter randomized controlled trial
Despite optimal medical management (OMM), low back pain (LBP) can be disabling, particularly after spinal surgery. Spinal cord stimulation (SCS) is effective in reducing neuropathic leg pain; however, evidence is limited for LBP. This prospective, open-label, parallel-group trial randomized (1:1) failed back surgery syndrome (FBSS) patients with predominant LBP to SCS plus OMM (SCS group) or OMM alone (OMM group) at 28 sites in Europe and the Americas. If trial stimulation was successful, a multicolumn SCS system was implanted. Outcomes were assessed at baseline (before randomization) and at 1, 3, 6, and 12 months after ra...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

The serum protease network—one key to understand complex regional pain syndrome pathophysiology
Complex regional pain syndrome (CRPS) develops after fracture. The acute CRPS phenotype resembles exaggerated inflammation, which is explained by local and systemic activation of a proinflammatory network including peptides and cytokines. Epidemiologic data suggest that inactivation of the peptidase angiotensin-converting enzyme in patients treated for hypertension increases the odds to develop CRPS. This hint leads us to investigate the serum protease network activity in patients with CRPS vs respective controls. For this purpose, we developed a dabsyl-bradykinin (DBK)-based assay and used it to investigate patients with ...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Nociceptin/orphanin FQ receptor modulates painful and fatigue symptoms in a mouse model of fibromyalgia
This study investigated the effects of nociceptin/orphanin FQ (N/OFQ) receptor (NOPr) ligands and the modulation of the NOP system in the preclinical mouse model of reserpine-induced fibromyalgia. The effects of administration of the natural agonist N/OFQ and the selective NOPr antagonists (UFP-101 and SB-612111) were evaluated in fibromyalgia-related symptoms in reserpine-treated mice. The expression of prepronociceptin/orphanin FQ and NOPr was assessed in central and peripheral sites at different time points after reserpine administration. Nociceptin/orphanin FQ displayed dual effects in the behavioral changes in the res...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

SUMMIT-07: a randomized trial of NKTR-181, a new molecular entity, full mu-opioid receptor agonist for chronic low-back pain
NKTR-181, a new molecular entity, mu-opioid receptor agonist with an inherently slow rate of central nervous system (CNS) entry, was designed to provide analgesia while reducing abuse potential. This phase 3, enriched-enrollment, randomized-withdrawal trial evaluated the analgesic efficacy, safety, and tolerability of NKTR-181 in patients with chronic low-back pain (CLBP). Adults with moderate-to-severe CLBP refractory to nonopioid analgesics achieving an analgesic NKTR-181 dosage (100-400 mg twice daily) during the open-label titration period were randomized to continued NKTR-181 treatment, double-blind, or switched to pl...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Insight into the genetic architecture of back pain and its risk factors from a study of 509,000 individuals
Back pain (BP) is a common condition of major social importance and poorly understood pathogenesis. Combining data from the UK Biobank and CHARGE consortium cohorts allowed us to perform a very large genome-wide association study (total N = 509,070) and examine the genetic correlation and pleiotropy between BP and its clinical and psychosocial risk factors. We identified and replicated 3 BP-associated loci, including one novel region implicating SPOCK2/CHST3 genes. We provide evidence for pleiotropic effects of genetic factors underlying BP, height, and intervertebral disk problems. We also identified independent genetic c...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Differential activation of ascending noxious pathways associated with trigeminal nerve injury
Trigeminal spinal subnucleus caudalis (Vc) neurons that project to the ventral posteromedial thalamic nucleus (VPM) and parabrachial nucleus (PBN) are critical for orofacial pain processing. We hypothesized that persistent trigeminal nerve injury differentially alters the proportion of Vc neurons that project to VPM and PBN in a modality-specific manner. Neuroanatomical approaches were used to quantify the number of Vc neurons projecting to VPM or PBN after chronic constriction injury of the infraorbital nerve (ION-CCI) and subsequent upper-lip stimulation. Male rats received injections of retrograde tracer fluorogold into...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

The role of Nav1.7 in human nociceptors: insights from human induced pluripotent stem cell–derived sensory neurons of erythromelalgia patients
The chronic pain syndrome inherited erythromelalgia (IEM) is attributed to mutations in the voltage-gated sodium channel (NaV) 1.7. Still, recent studies targeting NaV1.7 in clinical trials have provided conflicting results. Here, we differentiated induced pluripotent stem cells from IEM patients with the NaV1.7/I848T mutation into sensory nociceptors. Action potentials in these IEM nociceptors displayed a decreased firing threshold, an enhanced upstroke, and afterhyperpolarization, all of which may explain the increased pain experienced by patients. Subsequently, we investigated the voltage dependence of the tetrodotoxin-...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Analgesic prescribing trends in a national sample of older veterans with osteoarthritis: 2012-2017
Few investigations examine patterns of opioid and nonopioid analgesic prescribing and concurrent pain intensity ratings before and after institution of safer prescribing programs such as the October 2013 Veterans Health Administration system-wide Opioid Safety Initiative (OSI) implementation. We conducted a quasi-experimental pre–post observational study of all older U.S. veterans (≥50 years old) with osteoarthritis of the knee or hip. All associated outpatient analgesic prescriptions and outpatient pain intensity ratings from January 1, 2012 to December 31, 2016, were analyzed with segmented regression of interru...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Abnormal medial prefrontal cortex functional connectivity and its association with clinical symptoms in chronic low back pain
Accumulating evidence has shown that complicated brain systems are involved in the development and maintenance of chronic low back pain (cLBP), but the association between brain functional changes and clinical outcomes remains unclear. Here, we used resting-state functional magnetic resonance imaging (fMRI) and multivariate pattern analysis to identify abnormal functional connectivity (FC) between the default mode, sensorimotor, salience, and central executive brain networks in cLBP and tested whether abnormal FCs are related to pain and comorbid symptoms. Fifty cLBP patients and 44 matched healthy controls (HCs) underwent...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Pain coping skills training for African Americans with osteoarthritis: results of a randomized controlled trial
African Americans bear a disproportionate burden of osteoarthritis (OA), but they have been underrepresented in trials of behavioral interventions for pain. This trial examined a culturally tailored pain coping skills training (CST) program, compared to a wait list control group, among 248 African Americans with knee or hip OA. The pain CST program involved 11 telephone-based sessions over 3 months. Outcomes were assessed at baseline, 3 months (primary), and 9 months, and included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale (primary outcome), WOMAC total score and function subsc...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Platelet-derived growth factor activates nociceptive neurons by inhibiting M-current and contributes to inflammatory pain
Endogenous inflammatory mediators contribute to the pathogenesis of pain by acting on nociceptors, specialized sensory neurons that detect noxious stimuli. Here, we describe a new factor mediating inflammatory pain. We show that platelet-derived growth factor (PDGF)-BB applied in vitro causes repetitive firing of dissociated nociceptor-like rat dorsal root ganglion neurons and decreased their threshold for action potential generation. Injection of PDGF-BB into the paw produced nocifensive behavior in rats and led to thermal and mechanical pain hypersensitivity. We further detailed the biophysical mechanisms of these PDGF-B...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Quantitative assessment of nonpelvic pressure pain sensitivity in urologic chronic pelvic pain syndrome: a MAPP Research Network study
Experimental pain sensitivity was assessed in individuals with urologic chronic pelvic pain syndrome (UCPPS) as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network. A series of computer-controlled pressure stimuli were delivered to the thumbnail bed, an asymptomatic site distant from the area of UCPPS pain that is considered to be indicative of overall body pain threshold. Stimuli were rated according to a standardized magnitude estimation protocol. Pain sensitivity in participants with UCPPS was compared with healthy controls and a mixed pain group composed of individuals wit...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Compared to limb pain of other origin, ultrasonographic osteodensitometry reveals loss of bone density in complex regional pain syndrome
Local osteopenia and altered bone metabolism are major complications of complex regional pain syndrome (CRPS), but quantitative assessment is difficult unless using X-ray or dual-energy X-ray absorptiometry. Ultrasound-based measurement of bone density (UBD) is a possible alternative but has never been used to detect unilateral disease such as CRPS. Therefore, the main outcome measure of this prospective study was the diagnostic utility of UBD in patients with lower-limb CRPS. Second, we compared the extent of unilateral and contralateral calcaneal bone density to that of other conditions with unilateral pain, general oste...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

The medial temporal lobe in nociception: a meta-analytic and functional connectivity study
Recent neuroimaging studies implicate the medial temporal lobe (MTL) in nociception and pain modulation. Here, we aim to identify which subregions of the MTL are involved in human pain and to test its connectivity in a cohort of chronic low-back pain patients (CBP). We conducted 2 coordinate-based meta-analyses to determine which regions within the MTL showed consistent spatial patterns of functional activation (1) in response to experimental pain in healthy participants and (2) in chronic pain compared with healthy participants. We followed PRISMA guidelines and performed activation likelihood estimate (ALE) meta-analyses...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

System strengthening to support value-based care and healthy ageing for people with chronic pain
No abstract available (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Perspective Source Type: research

Navigating trials of personalized pain treatments: we're going to need a bigger boat
No abstract available (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Topical Review Source Type: research

Trajectories of sickness absence and disability pension before and after opioid initiation for noncancer pain: a 10-year population-based study
The objectives of this study were to identify trajectories of SA/DP before and after strong and weak opioid initiation for noncancer pain and the factors associated with these trajectories. A longitudinal population-based study of 201,641 people (24-59 years) without cancer who initiated opioid analgesics in 2009 in Sweden was conducted. Trajectories of net annual SA/DP days in the 5 years before/after opioid initiation were estimated with group-based trajectory modelling. Multinomial logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with trajectory groups....
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Anterior nucleus of paraventricular thalamus mediates chronic mechanical hyperalgesia
Pain-related diseases are the top leading causes of life disability. Identifying brain regions involved in persistent neuronal changes will provide new insights for developing efficient chronic pain treatment. Here, we showed that anterior nucleus of paraventricular thalamus (PVA) plays an essential role in the development of mechanical hyperalgesia in neuropathic and inflammatory pain models in mice. Increase in c-Fos, phosphorylated extracellular signal–regulated kinase, and hyperexcitability of PVA neurons were detected in hyperalgesic mice. Direct activation of PVA neurons using optogenetics and pharmacological a...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Pain-related nucleus accumbens function: modulation by reward and sleep disruption
This study aimed to determine whether NAc function at the onset and offset of a noxious thermal stimulus is enhanced by rewarding music, and whether that effect is reversed by experimental sleep disruption. Twenty-one healthy subjects underwent functional magnetic resonance imaging scans on 2 separate days after both uninterrupted sleep and experimental sleep disruption. During functional magnetic resonance imaging scans, participants experienced noxious stimulation while listening to individualized rewarding or neutral music. Behavioral results revealed that rewarding music significantly reduced pain intensity compared wi...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Effectiveness and safety of 5% lidocaine-medicated plaster on localized neuropathic pain after knee surgery: a randomized, double-blind controlled trial
This study focuses on the effectiveness of LP5 on allodynia, hyperalgesia, and thermal stimuli in postsurgery knee localized neuropathic pain. A randomized double-blind, 2 parallel groups, controlled trial (NCT02763592) took place in 36 patients (age, 69.4 ± 7.3 years) at the Clinical Pharmacology Center, University Hospital Clermont-Ferrand, France. Patients randomly received LP5 or placebo plaster during 3 months. Neuropathic pain intensity and several parameters (dynamic mechanical allodynia, mechanical [von Frey], heat and cold detection and pain thresholds [Pathway Medoc], and size of the allodynic area were re...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Mirogabalin for the management of postherpetic neuralgia: a randomized, double-blind, placebo-controlled phase 3 study in Asian patients
This study investigated the safety and efficacy of mirogabalin, a novel, potent, selective ligand of the α2δ subunit of voltage-dependent Ca2+ channels, for the treatment of postherpetic neuralgia (PHN). In this multicenter, double-blind, placebo-controlled phase 3 study, Asian patients ≥20 years with PHN were randomized 2:1:1:1 to placebo or mirogabalin 15, 20, or 30 mg/day for up to 14 weeks (NCT02318719). The primary efficacy endpoint was the change from baseline in average daily pain score at week 14, defined as a weekly average of daily pain (0 = “no pain” to 10 = “worst possible pain,...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Spinal somatostatin-positive interneurons transmit chemical itch
Recent studies have made significant progress in identifying distinct populations of peripheral neurons involved in itch transmission, whereas the cellular identity of spinal interneurons that contribute to itch processing is still a debate. Combining genetic and pharmacological ablation of spinal excitatory neuronal subtypes and behavioral assays, we demonstrate that spinal somatostatin-positive (SOM+) excitatory interneurons transmit pruritic sensation. We found that the ablation of spinal SOM+/Lbx1+ (SOMLbx1) neurons caused significant attenuation of scratching responses evoked by various chemical pruritogens (chemical ...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Normative data for common pain measures in chronic pain clinic populations: closing a gap for clinicians and researchers
In this study, we summarised data from 13,343 heterogeneous patients on several commonly used pain questionnaires that were routinely collected from 36 pain clinics in Australia and New Zealand as part of the electronic Persistent Pain Outcomes Collaboration (ePPOC) including the Brief Pain Inventory (BPI); the Depression Anxiety and Stress Scales (DASS); the Pain Self-Efficacy Questionnaire (PSEQ); and the Pain Catastrophizing Scale (PCS). The data are presented as summarised normative data, broken down by demographic (age, sex, work status, etc) and pain site/medical variables. The mean BPI severity score was 6.4 (modera...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Peripheral oxytocin restores light touch and nociceptor sensory afferents towards normal after nerve injury
Oxytocin reduces primary sensory afferent excitability and produces analgesia in part through a peripheral mechanism, yet its actions on physiologically characterized, mechanically sensitive afferents in normal and neuropathic conditions are unknown. We recorded intracellularly from L4 dorsal root ganglion neurons characterized as low-threshold mechanoreceptors (LTMRs) or high-threshold mechanoreceptors (HTMRs) in female rats 1 week after L5 partial spinal nerve injury or sham control (n = 24 rats/group) before, during, and after ganglionic perfusion with oxytocin, 1 nM. Nerve injury desensitized and hyperpolarized LTMRs (...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Opioid cessation and chronic pain: perspectives of former opioid users
Current guidelines for addressing opioid cessation in the context of chronic pain management recommend that opioids be discontinued if the risks outweigh the benefits. However, few studies have focused on understanding opioid cessation from the perspective of individuals with chronic pain. This mixed-method study included 49 former opioid users with chronic pain and used quantitative survey data and qualitative focus group data to identify themes pertaining to former opioid user's experience before, during, and after opioid cessation. Participants described several reasons for wanting to stop opioids including lack of effi...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Chronic pain is associated with a brain aging biomarker in community-dwelling older adults
Chronic pain is associated with brain atrophy with limited evidence on its impact in the older adult's brain. We aimed to determine the associations between chronic pain and a brain aging biomarker in persons aged 60 to 83 years old. Participants of the Neuromodulatory Examination of Pain and Mobility Across the Lifespan (NEPAL) study (N = 47) completed demographic, psychological, and pain assessments followed by a quantitative sensory testing battery and a T1-weighted magnetic resonance imaging. We estimated a brain-predicted age difference (brain-PAD) that has been previously reported to predict overall mortality risk (b...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Adenosine A3 receptor activation inhibits pronociceptive N-type Ca2+ currents and cell excitability in dorsal root ganglion neurons
Recently, studies have focused on the antihyperalgesic activity of the A3 adenosine receptor (A3AR) in several chronic pain models, but the cellular and molecular basis of this effect is still unknown. Here, we investigated the expression and functional effects of A3AR on the excitability of small- to medium-sized, capsaicin-sensitive, dorsal root ganglion (DRG) neurons isolated from 3- to 4-week-old rats. Real-time quantitative polymerase chain reaction experiments and immunofluorescence analysis revealed A3AR expression in DRG neurons. Patch-clamp experiments demonstrated that 2 distinct A3AR agonists, Cl-IB-MECA and the...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

An investigation of the effect of experimental pain on logical reasoning
Pain disrupts attention to prioritise avoidance of harm and promote analgesic behaviour. This could in turn have negative effects on higher-level cognitions, which rely on attention. In the current article, we examined the effect of thermal pain induction on 3 measures of reasoning: the Cognitive Reflection Test, Belief Bias Syllogisms task, and Conditional Inference task. In experiment 1, the thermal pain was set at each participant's pain threshold. In experiment 2, it was set to a minimum of 44°C or 7/10 on a visual analogue scale (whichever was higher). In experiment 3, performance was compared in no pain, low-inte...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Sirtuin 1 alleviates diabetic neuropathic pain by regulating synaptic plasticity of spinal dorsal horn neurons
In this study, we found that in the spinal dorsal horn of diabetic neuropathic pain (DNP) rats and db/db mice, decreased SIRT1 expression was accompanied by enhanced structural synaptic plasticity. The levels of postsynaptic density protein 95 (PSD-95), growth-associated protein 43 (GAP43), and synaptophysin increased in the spinal dorsal horn of DNP rats and db/db mice and in high glucose–cultured primary spinal neurons. Upregulation of spinal SIRT1 by SIRT1 activator SRT1720 relieved pain behavior, inhibited the enhanced structural synaptic plasticity in rats and db/db mice with DNP, and decreased the levels of syn...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Haploinsufficiency of the brain-derived neurotrophic factor gene is associated with reduced pain sensitivity
Rare pain-insensitive individuals offer unique insights into how pain circuits function and have led to the development of new strategies for pain control. We investigated pain sensitivity in humans with WAGR (Wilms tumor, aniridia, genitourinary anomaly, and range of intellectual disabilities) syndrome, who have variably sized heterozygous deletion of the 11p13 region. The deletion region can be inclusive or exclusive of the brain-derived neurotrophic factor (BDNF) gene, a crucial trophic factor for nociceptive afferents. Nociceptive responses assessed by quantitative sensory testing demonstrated reduced pain sensitivity ...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Hedonic drinking engages a supraspinal inhibition of thermal nociception in adult rats
The taste of sucrose is commonly used to provide pain relief in newborn humans and is innately analgesic to neonatal rodents. In adulthood, sucrose remains a strong motivator to feed, even in potentially hazardous circumstances (ie, threat of tissue damage). However, the neurobiological mechanisms of this endogenous reward–pain interaction are unclear. We have developed a simple model of sucrose drinking–induced analgesia in Sprague–Dawley rats (6-10 weeks old) and have undertaken a behavioral and pharmacological characterization using the Hargreaves' test of hind-paw thermal sensitivity. Our results reve...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Intact mast cell content during mild head injury is required for development of latent pain sensitization: implications for mechanisms underlying post-traumatic headache
Post-traumatic headache (PTH) is one of the most common, debilitating, and difficult symptoms to manage after a traumatic head injury. Although the mechanisms underlying PTH remain elusive, recent studies in rodent models suggest the potential involvement of calcitonin gene–related peptide (CGRP), a mediator of neurogenic inflammation, and the ensuing activation of meningeal mast cells (MCs), proalgesic resident immune cells that can lead to the activation of the headache pain pathway. Here, we investigated the relative contribution of MCs to the development of PTH-like pain behaviors in a model of mild closed-head i...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Sex differences in central nervous system plasticity and pain in experimental autoimmune encephalomyelitis
Multiple sclerosis (MS) is a neurodegenerative autoimmune disease with many known structural and functional changes in the central nervous system. A well-recognized, but poorly understood, complication of MS is chronic pain. Little is known regarding the influence of sex on the development and maintenance of MS-related pain. This is important to consider, as MS is a predominantly female disease. Using the experimental autoimmune encephalomyelitis (EAE) mouse model of MS, we demonstrate sex differences in measures of spinal cord inflammation and plasticity that accompany tactile hypersensitivity. Although we observed substa...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Extended-release gabapentin for failed back surgery syndrome: results from a randomized double-blind cross-over study
Persistent pain after lumbar surgery (failed back surgery syndrome [FBSS]) remains a leading indication for chronic analgesia. However, no analgesics have proven efficacious for this condition. Although trials have evaluated gabapentinoids for chronic low back pain, none of these trials focused solely on FBSS. This randomized, double-blind cross-over trial evaluated the efficacy of gabapentin (1800 mg/day) for FBSS. Eligible patients had a diagnosis of FBBS, an average daily pain score of at least 4 of 10, a neuropathic pain component (indicated by the PainDetect), and reported at least half of their pain radiating in thei...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Increased pain sensitivity but normal pain modulation in adolescents with migraine
Inhibitory pain modulation has been reported to be deficient in adults across different types of chronic pain, including migraine. To determine whether a similar phenomenon occurs in youth, we performed a quantitative sensory testing investigation in adolescents with migraine (N = 19). These patients were compared to healthy adolescents with (Fam-His; N = 20) or without (Healthy; N = 29) a family history of migraine (eg, first-degree relative with migraine). Subjects were first familiarized with the stimuli and visual analogue rating scales using graded noxious stimuli (0°C, 43-49°C range). These data were used to ...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Towards a neurobiological understanding of pain in neurofibromatosis type 1: mechanisms and implications for treatment
Neurofibromatosis type 1 (NF1) is the most common of a group of rare diseases known by the term, “Neurofibromatosis,” affecting 1 in 3000 to 4000 people. NF1 patients present with, among other disease complications, café au lait patches, skin fold freckling, Lisch nodules, orthopedic complications, cutaneous neurofibromas, malignant peripheral nerve sheath tumors, cognitive impairment, and chronic pain. Although NF1 patients inevitably express pain as a debilitating symptom of the disease, not much is known about its manifestation in the NF1 disease, with most current information coming from sporadic cas...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Narrative Review Source Type: research

Alexithymia in individuals with chronic pain and its relation to pain intensity, physical interference, depression, and anxiety: a systematic review and meta-analysis
Numerous studies have examined how alexithymia (difficulty identifying and describing one's emotions and a preference for externally oriented thinking) relates to chronic pain and associated disability. We conducted a systematic review and meta-analysis to summarize individual studies that either assessed alexithymia in individuals with chronic pain vs controls or related alexithymia to pain intensity, physical interference, depression, and anxiety. We searched MEDLINE, Embase, and PsycINFO from inception through June 2017; 77 studies met the criteria (valid assessment of alexithymia in adults or children with any chronic ...
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Systematic Review and Meta-Analysis Source Type: research

Music-induced analgesia: how does music relieve pain?
No abstract available (Source: Pain)
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Topical Review Source Type: research

Untangling a canopy of spinal itch circuits
No abstract available (Source: Pain)
Source: Pain - April 25, 2019 Category: Anesthesiology Tags: Commentary Source Type: research

The association between multiple sclerosis and pain medications: Erratum.
No abstract available (Source: Pain)
Source: Pain - March 26, 2019 Category: Anesthesiology Tags: Erratum Source Type: research

Reply
No abstract available (Source: Pain)
Source: Pain - March 26, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research