Nucleus accumbens: a novel forebrain mechanism underlying the increase in pain sensitivity caused by rapid eye movement sleep deprivation
No abstract available (Source: Pain)
Source: Pain - January 1, 2018 Category: Anesthesiology Tags: Commentary Source Type: research

Sleep and pain are definitely coupled—but how tight is this coupling?
No abstract available (Source: Pain)
Source: Pain - January 1, 2018 Category: Anesthesiology Tags: Commentary Source Type: research

Spousal criticism and hostility in response to pain: what is the alternative?
No abstract available (Source: Pain)
Source: Pain - January 1, 2018 Category: Anesthesiology Tags: Commentary Source Type: research

Investigating generalizability of results from a randomized controlled trial of the management of chronic widespread pain: the MUSICIAN study Erratum.
No abstract available (Source: Pain)
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Erratum Source Type: research

Brain-derived neurotrophic factor–mediated projection-specific regulation of depressive-like and nociceptive behaviors in the mesolimbic reward circuitry
In this study, we investigated the output-specific regulatory roles of dopaminergic (DA) neurons within the ventral tegmental area (VTA) in depressive-like and nociceptive behaviors in mice subjected to unpredictable chronic mild stress (CMS), using the projection-specific electrophysiological recording, pharmacological manipulation, behavioral test, and molecular biology technologies. We demonstrated that CMS decreased the firing activity in VTA projecting to medial prefrontal cortex (VTA → mPFC), but not in VTA to nucleus accumbens (VTA → NAc), DA neurons. However, both VTA → mPFC and VTA → NAc DA neu...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Influence of catechol-O-methyltransferase Val158Met on fear of pain and placebo analgesia
Higher levels of fear have been shown to partly explain individual differences in placebo analgesic responding. The catechol-O-methyltransferase (COMT) rs4680 Val158Met polymorphism has been associated with both increased placebo analgesia and increased fear-related behavior, in what appears to be inconsistent findings in the literature. The aim of the study was therefore to investigate placebo analgesia and fear-related processes with regard to the COMT genotype, to sort out whether the Met-allele is associated with increased placebo analgesia or increased fear of pain (FOP). A 3 Group (Emla, placebo and natural history) ...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Differential effect of motor cortex stimulation on unit activities in the ventral posterior lateral thalamus in cats
Although motor cortex stimulation (MCS) is being increasingly used to treat chronic refractory neuropathic pain in humans, its mechanisms of action remain elusive. Studies in animals have suggested the involvement of subcortical structures, in particular, the thalamus. Most of these studies have been performed in rats, a species presenting significant differences in thalamic anatomy and function relative to primates, in particular, a very limited number of thalamic GABA interneurons. The aim of this study was to investigate the effects of MCS on single-unit activities of the thalamic ventral posterior lateral (VPL) nucleus...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

High-risk prescribing and opioid overdose: prospects for prescription drug monitoring program–based proactive alerts
To develop a simple, valid model to identify patients at high risk of opioid overdose–related hospitalization and mortality, Oregon prescription drug monitoring program, Vital Records, and Hospital Discharge data were linked to estimate 2 logistic models; a first model that included a broad range of risk factors from the literature and a second simplified model. Receiver operating characteristic curves, sensitivity, and specificity of the models were analyzed. Variables retained in the final model were categories such as older than 35 years, number of prescribers, number of pharmacies, and prescriptions for long-acti...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Antisense oligonucleotides selectively suppress target RNA in nociceptive neurons of the pain system and can ameliorate mechanical pain
There is an urgent need for better treatments for chronic pain, which affects more than 1 billion people worldwide. Antisense oligonucleotides (ASOs) have proven successful in treating children with spinal muscular atrophy, a severe infantile neurological disorder, and several ASOs are currently being tested in clinical trials for various neurological disorders. Here, we characterize the pharmacodynamic activity of ASOs in spinal cord and dorsal root ganglia (DRG), key tissues for pain signaling. We demonstrate that activity of ASOs lasts up to 2 months after a single intrathecal bolus dose. Interestingly, comparison of su...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Effectiveness and costs of a vocational advice service to improve work outcomes in patients with musculoskeletal pain in primary care: a cluster randomised trial (SWAP trial ISRCTN 52269669)
Musculoskeletal pain is a common cause of work absence, and early intervention is advocated to prevent the adverse health and economic consequences of longer-term absence. This cluster randomised controlled trial investigated the effect of introducing a vocational advice service into primary care to provide occupational support. Six general practices were randomised; patients were eligible if they were consulting their general practitioner with musculoskeletal pain and were employed and struggling at work or absent from work (Source: Pain)
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Chronic pain-related changes in cardiovascular regulation and impact on comorbid hypertension in a general population: the Tromsø study
Heart rate variability (HRV) and baroreflex sensitivity (BRS) are indexes reflecting the ability to maintain cardiovascular homeostasis amidst changing conditions. Evidence primarily from small studies suggests that both HRV and BRS may be reduced in individuals with chronic pain (CP), with potential implications for cardiovascular risk. We compared HRV and BRS between individuals with CP (broadly defined) and pain-free controls in a large unselected population sample. Participants were 1143 individuals reporting clinically meaningful CP and 5640 pain-free controls who completed a 106-second cold pressor test (CPT). Partic...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Brain oscillations reflecting pain-related behavior in freely moving rats
Recording oscillatory brain activity holds great promise in pain research. However, experimental results are variable and often difficult to reconcile. Some of these inconsistencies arise from the use of hypothesis-driven analysis approaches that (1) do not assess the consistency of the observed responses within and across individuals, and (2) do not fully exploit information sampled across the entire cortex. Here, we address these issues by recording the electrocorticogram directly from the brain surface of 12 freely moving rats. Using a hypothesis-free approach, we isolated brain oscillations induced by graded nociceptiv...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Pyrethroids inhibit K2P channels and activate sensory neurons: basis of insecticide-induced paraesthesias
Pyrethroid insecticides are widely used for pest control in agriculture or in human public health commonly as a topical treatment for scabies and head lice. Exposure to pyrethroids such as permethrin or tetramethrin (TM) causes sensory alterations such as transient pain, burning, stinging sensations, and paraesthesias. Despite the well-known effects of pyrethroids on sodium channels, actions on other channels that control sensory neuron excitability are less studied. Given the role of 2-pore domain potassium (K2P) channels in modulating sensory neuron excitability and firing, both in physiological and pathological conditio...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Guideline-recommended vs high-dose long-term opioid therapy for chronic noncancer pain is associated with better health outcomes: data from a representative sample of the German population
Recent evidence-based guidelines for long-term opioid therapy (LTOT) for chronic noncancer pain (CNCP) have defined daily morphine equivalent doses (MEQ/d) that require particular caution. The recommendation for a threshold MEQ/d is based on North American studies that have demonstrated negative health outcomes associated with high-dose LTOT for CNCP. We have conducted a retrospective cross-sectional study using an anonymized German health claims database, including 4,028,618 persons insured by 69 German statutory health insurances, representative of age and sex for the German population in 2014. Those receiving German gui...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Nucleus accumbens mediates the pronociceptive effect of sleep deprivation: the role of adenosine A2A and dopamine D2 receptors
Sleep disorders increase pain sensitivity and the risk of developing painful conditions; however, the underlying mechanisms are poorly understood. It has been suggested that nucleus accumbens (NAc) influences sleep-wake cycle by means of a balance between adenosine activity at A2A receptors and dopamine activity at D2 receptors. Because the NAc also plays an important role in pain modulation, we hypothesized that the NAc and its A2A and D2 receptors mediate the pronociceptive effect of rapid eye movement (REM) sleep deprivation (SD). We found that 24 hours of REM-SD induced an intense pronociceptive effect in Wistar rats, ...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Trajectories of musculoskeletal pain from adolescence to middle age: the role of early depressive symptoms, a 27-year follow-up of the Northern Swedish Cohort
Depression and musculoskeletal pain are associated, but long-term follow-up studies are rare. We aimed to examine the relationship of early depressive symptoms with developmental patterns of musculoskeletal pain from adolescence to middle age. Adolescents ending compulsory school (age 16) in Luleå, Northern Sweden, in 1981 (n = 1083) were studied and followed up in 1986, 1995, and 2008 (age 43) for musculoskeletal pain. Attrition was very low. Indicators for any and severe pain were based on pain in the neck-shoulders, low back, and the extremities. Latent class growth analyses were performed on 563 men and 503 women...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Trajectories of pain severity in juvenile idiopathic arthritis: results from the Research in Arthritis in Canadian Children Emphasizing Outcomes cohort
We studied children enrolled within 90 days of juvenile idiopathic arthritis diagnosis in the Research in Arthritis in Canadian Children Emphasizing Outcomes (ReACCh-Out) prospective inception cohort to identify longitudinal trajectories of pain severity and features that may predict pain trajectory at diagnosis. A total of 1062 participants were followed a median of 24.3 months (interquartile range = 16.0-37.1 months). Latent trajectory analysis of pain severity, measured in a 100-mm visual analogue scale, identified 5 distinct trajectories: (1) mild-decreasing pain (56.2% of the cohort); (2) moderate-decreasing pain (28....
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

The CALI-9: A brief measure for assessing activity limitations in children and adolescents with chronic pain
Pain-related functional limitations represent an important outcome domain to assess in children and adolescents with chronic pain. The aim of this study was to extend the empirical support of the 21-item Child Activity Limitations Interview (CALI-21), a well-validated measure of activity limitations, using a large, multisite sample and to develop a brief form of the measure with more interpretable scoring. A sample of 1616 youth and 1614 parents completed the CALI-21 at an initial appointment in 1 of 3 pain specialty clinics in the Midwest or Northwest United States, or as part of a research study after this initial visit....
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Chronic pain in families: a cross-sectional study of shared social, behavioural, and environmental influences
This study aimed to investigate the family-level contribution to an individual's chronic pain status. This was a cross-sectional study using the Generation Scotland: Scottish Family Health Study data set. This study focused on a nested cohort of dyads (only 2 relatives per family, n = 2714). Multi-level modelling was first performed to estimate the extent of variance in chronic pain at the family level. Then each member of the dyad was randomly assigned as either the exposure or outcome family member, and logistic regression was used to identify shared factors associated with the outcome of chronic pain status. Multi-level...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Chronic exposure to insufficient sleep alters processes of pain habituation and sensitization
Chronic pain conditions are highly comorbid with insufficient sleep. While the mechanistic relationships between the 2 are not understood, chronic insufficient sleep may be 1 pathway through which central pain-modulatory circuits deteriorate, thereby contributing to chronic pain vulnerability over time. To test this hypothesis, an in-laboratory model of 3 weeks of restricted sleep with limited recovery (5 nights of 4-hour sleep per night followed by 2 nights of 8-hour sleep per night) was compared with 3 weeks of 8-hour sleep per night (control protocol). Seventeen healthy adults participated, with 14 completing both 3-wee...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Spouse criticism and hostility during marital interaction: effects on pain intensity and behaviors among individuals with chronic low back pain
Individuals with chronic pain may experience negative responses from spouse, family, and friends. Responses such as overt criticism and hostility may be associated with worsening pain and function for chronic pain sufferers. We used a laboratory procedure to evaluate whether variability in spouse criticism/hostility exhibited toward chronic low back pain (CLBP) patients during a conflictual discussion predicted variability in patient pain and function during a subsequent pain-induction task. Chronic low back pain patients (n = 71) and their spouses (n = 71) participated in a 10-minute discussion followed by the patient und...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Quantitative sensory testing response patterns to capsaicin- and ultraviolet-B–induced local skin hypersensitization in healthy subjects: a machine-learned analysis
This study provided a 246 × 10-sized data matrix (82 subjects assessed at baseline, following UV-B application, and following capsaicin application) with respect to 10 QST parameters, which we analyzed using machine-learning techniques. We observed statistically significant effects of the hypersensitization treatments in 9 different QST parameters. Supervised machine-learned analysis implemented as random forests followed by ABC analysis pointed to heat pain thresholds as the most relevantly affected QST parameter. However, decision tree analysis indicated that UV-B additionally modulated sensitivity to cold. Unsuper...
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Tired of pain? Toward a better understanding of fatigue in chronic pain
No abstract available (Source: Pain)
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Topical Review Source Type: research

Nucleus accumbens: a novel forebrain mechanism underlying the increase in pain sensitivity caused by rapid eye movement sleep deprivation
No abstract available (Source: Pain)
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Commentary Source Type: research

Sleep and pain are definitely coupled—but how tight is this coupling?
No abstract available (Source: Pain)
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Commentary Source Type: research

Spousal criticism and hostility in response to pain: what is the alternative?
No abstract available (Source: Pain)
Source: Pain - December 22, 2017 Category: Anesthesiology Tags: Commentary Source Type: research

Reply
No abstract available (Source: Pain)
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Correspondence Source Type: research

Reporting randomized controlled trial quality and search date in systematic reviews and meta-analyses
No abstract available (Source: Pain)
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Correspondence Source Type: research

Reply
No abstract available (Source: Pain)
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Correspondence Source Type: research

Cardiac vagal tone as a reliable index of pain chronicity and severity
No abstract available (Source: Pain)
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Correspondence Source Type: research

High levels of cerebrospinal fluid chemokines point to the presence of neuroinflammation in peripheral neuropathic pain: a cross-sectional study of 2 cohorts of patients compared with healthy controls
Abstract Animal models suggest that chemokines are important mediators in the pathophysiology of neuropathic pain. Indeed, these substances have been called “gliotransmitters,” a term that illustrates the close interplay between glial cells and neurons in the context of neuroinflammation and pain. However, evidence in humans is scarce. The aim of the study was to determine a comprehensive cerebrospinal fluid (CSF) inflammatory profile of patients with neuropathic pain. Our hypothesis was that we would thereby find indications of a postulated on-going process of central neuroinflammation. Samples of CSF were c...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Photosensitization of TRPA1 and TRPV1 by 7-dehydrocholesterol: implications for the Smith–Lemli–Opitz syndrome
Abstract Loss-of-function mutations in the enzyme 7-dehydrocholesterol reductase are responsible for the Smith–Lemli–Opitz syndrome, in which 7-dehydrocholesterol (7-DHC) levels are markedly increased in the plasma and tissues of patients. This increase in 7-DHC is probably associated with the painful and itchy photosensitivity reported by the majority of patients with Smith–Lemli–Opitz syndrome. To identify the molecular targets involved in the activation and photosensitization of primary afferents by 7-DHC, we focused on TRPA1 and TRPV1, two ion channels expressed in nociceptive nerve endings an...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

MicroRNA–mediated downregulation of potassium-chloride-cotransporter and vesicular γ-aminobutyric acid transporter expression in spinal cord contributes to neonatal cystitis–induced visceral pain in rats
Abstract Loss of GABAergic inhibition in pain pathways has been considered to be a key component in the development of chronic pain. In the present study, we intended to examine whether miR-92b–mediated posttranscriptional dysregulation of spinal potassium chloride cotransporter (KCC2) and vesicular γ-aminobutyric acid transporter (VGAT) plays a major role in the development and maintenance of long-term visceral hyperalgesia in neonatal zymosan–treated rats. Neonatal cystitis was induced by transurethral zymosan administration from postnatal (P) days 14 to 16 (protocol 1). Two other zymosan protocols we...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Cannabis constituent synergy in a mouse neuropathic pain model
We examined the basis for this phytocannabinoid interaction in a mouse chronic constriction injury (CCI) model of neuropathic pain. Acute systemic administration of THC dose-dependently reduced CCI-induced mechanical and cold allodynia, but also produced motor incoordination, catalepsy, and sedation. Cannabidiol produced a lesser dose-dependent reduction in allodynia, but did not produce the cannabinoid side effects. When co-administered in a fixed ratio, THC and CBD produced a biphasic dose-dependent reduction in allodynia. At low doses, the THC:CBD combination displayed a 200-fold increase in anti-allodynic potency, but ...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Attenuation of early phase inflammation by cannabidiol prevents pain and nerve damage in rat osteoarthritis
Abstract Osteoarthritis (OA) is a multifactorial joint disease, which includes joint degeneration, intermittent inflammation, and peripheral neuropathy. Cannabidiol (CBD) is a noneuphoria producing constituent of cannabis that has the potential to relieve pain. The aim of this study was to determine whether CBD is anti-nociceptive in OA, and whether inhibition of inflammation by CBD could prevent the development of OA pain and joint neuropathy. Osteoarthritis was induced in male Wistar rats (150-175 g) by intra-articular injection of sodium monoiodoacetate (MIA; 3 mg). On day 14 (end-stage OA), joint afferent mechanosens...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Bivalent ligand that activates mu opioid receptor and antagonizes mGluR5 receptor reduces neuropathic pain in mice
This study assessed whether intrathecal MMG22 also is effective in reducing pain of neuropathic origin. Furthermore, we theorized that MMG22 should reduce hyperalgesia in nerve-injured mice in a manner consistent with a synergistic interaction between MOR and mGluR5. Several weeks after spared nerve injury, tactile hypersensitivity was reversed in mice by the intrathecal injection of MMG22 (0.01-10 nmol) but also by its shorter spacer analog, MMG10, with similar potency. The potencies of the bivalent ligands were 10- to 14-fold higher than those of the compounds upon which the bivalent structure was based, the MOR agonist ...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Opioid prescription levels and postoperative outcomes in orthopedic surgery
Abstract Given the basic need for opioids in the perioperative setting, we investigated associations between opioid prescription levels and postoperative outcomes using population-based data of orthopedic surgery patients. We hypothesized that increased opioid amounts would be associated with higher risk for postoperative complications. Data were extracted from the national Premier Perspective database (2006-2013); N = 1,035,578 lower joint arthroplasties and N = 220,953 spine fusions. Multilevel multivariable logistic regression models measured associations between opioid dose prescription and postoperative outcomes, st...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Passive transfer autoimmunity in a mouse model of complex regional pain syndrome
Abstract It has been proposed that complex regional pain syndrome (CRPS) is a posttraumatic autoimmune disease, and we previously observed that B cells are required for the full expression of CRPS-like changes in a mouse tibia fracture CRPS model. The current study used the mouse model to evaluate the progression of postfracture CRPS-like changes in wild-type (WT) and muMT fracture mice lacking B cells and antibodies. The pronociceptive effects of injecting WT fracture mouse serum antibodies into muMT fracture mice were also evaluated. Postfracture pain behaviors transitioned from being initially dependent on both innate...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Tumor necrosis factor alpha secreted from oral squamous cell carcinoma contributes to cancer pain and associated inflammation
In this study, we used 2 oral cancer mouse models: a cell line supernatant injection model and the 4-nitroquinoline-1-oxide (4NQO) chemical carcinogenesis model. We used the 2 models to study changes in immune cell infiltrate and orofacial nociception associated with oral squamous cell carcinoma (oSCC). Oral cancer cell line supernatant inoculation and 4NQO-induced oSCC resulted in functional allodynia and neuronal sensitization of trigeminal tongue afferent neurons. Although the infiltration of immune cells is a prominent component of both oral cancer models, our use of immune-deficient mice demonstrated that oral cancer&...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Multiple sites and actions of gabapentin-induced relief of ongoing experimental neuropathic pain
Abstract Gabapentin (GBP) is a first-line therapy for neuropathic pain, but its mechanisms and sites of action remain uncertain. We investigated GBP-induced modulation of neuropathic pain following spinal nerve ligation (SNL) in rats. Intravenous or intrathecal GBP reversed evoked mechanical hypersensitivity and produced conditioned place preference (CPP) and dopamine (DA) release in the nucleus accumbens (NAc) selectively in SNL rats. Spinal GBP also significantly inhibited dorsal horn wide-dynamic-range neuronal responses to a range of evoked stimuli in SNL rats. By contrast, GBP microinjected bilaterally into the rost...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Monomethyl fumarate inhibits pain behaviors and amygdala activity in a rat arthritis model
Abstract Neuroplasticity in the amygdala, a brain center for emotions, leads to increased neuronal activity and output that can generate emotional-affective behaviors and modulate nocifensive responses. Mechanisms of increased activity in the amygdala output region (central nucleus, CeA) include increased reactive oxygen species, and so we explored beneficial effects of monomethyl fumarate (MMF), which can have neuroprotective effects through the nuclear factor (erythroid-derived 2)-like 2 (Nrf2) antioxidant response pathway. Systemic (intraperitoneal) MMF dose-dependently inhibited vocalizations and mechanosensitivity (...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Cerebral white matter structure is disrupted in Gulf War Veterans with chronic musculoskeletal pain
Abstract Chronic musculoskeletal pain (CMP) affects ∼25% of the 700,000 Veterans deployed during the Persian Gulf War (1990-1991). The cause of their pain is unknown, and there are no efficacious treatments. A small body of literature suggests that brain abnormalities exist in Gulf War Veterans (GVs), yet relationships between brain abnormalities and disease symptoms remain largely unexplored. Our purpose was to compare white matter (WM) integrity between GVCMP and matched, healthy Veteran controls (GVCO) and investigate relationships between cerebral WM integrity and symptoms. Thirty GVCMP and 31 controls completed ...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Emotional awareness and expression therapy, cognitive behavioral therapy, and education for fibromyalgia: a cluster-randomized controlled trial
Abstract Patients with fibromyalgia (FM) experience increased lifetime levels of psychosocial adversity, trauma, and emotional conflict. To address these risk factors, we developed emotion awareness and expression therapy (EAET) and tested its benefits against an active control condition, FM education, and the field's gold standard intervention for FM, cognitive behavioral therapy (CBT) for symptom management. Adults with FM (N = 230) formed 40 treatment groups, which were randomized to EAET, CBT, or education and given 8, 90-minute sessions. Patient-reported outcomes were assessed at baseline, posttreatment, and 6-month...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Sensory phenotype and risk factors for painful diabetic neuropathy: a cross-sectional observational study
Abstract Different sensory profiles in diabetic distal symmetrical sensory-motor polyneuropathy (DSPN) may be associated with pain and the responsiveness to analgesia. We aimed to characterize sensory phenotypes of patients with painful and painless diabetic neuropathy and to assess demographic, clinical, metabolic, and electrophysiological parameters related to the presence of neuropathic pain in a large cohort of well-defined DSPN subjects. This observational cross-sectional multi-center cohort study (performed as part of the ncRNAPain EU consortium) of 232 subjects with nonpainful (n = 74) and painful (n = 158) DSPN a...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Distinct behavioral responses evoked by selective optogenetic stimulation of the major TRPV1+ and MrgD+ subsets of C-fibers
Abstract Primary C-fiber nociceptors are broadly divided into peptidergic and nonpeptidergic afferents. TRPV1 is a thermosensitive cation channel mainly localized in peptidergic nociceptors, whereas MrgD is a sensory G protein–coupled receptor expressed in most nonpeptidergic nociceptive afferents. TRPV1+ and MrgD+ fibers have been reported to be primarily involved in thermal and mechanical nociception, respectively. Yet, their functional assessment in somatosensory transmission relied on ablation strategies that do not account for compensatory mechanisms. To achieve selective activation of these 2 major subsets of...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Is the rationale more important than deception? A randomized controlled trial of open-label placebo analgesia
Abstract Research on open-label placebos questions whether deception is a necessary characteristic of placebo effects. Yet, comparisons between open-label and deceptive placebos (DPs) are lacking. We therefore assessed effects of open-label placebos and DPs in comparison with no treatment (NT) with a standardized experimental heat pain paradigm in a randomized controlled trial in healthy participants. Participants (N = 160) were randomly assigned to NT, open-label placebo without rationale (OPR-), open-label placebo with rationale (OPR+), and DP. We conducted baseline and posttreatment measurements of heat pain threshold...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

CRISPR/Cas9 editing of Nf1 gene identifies CRMP2 as a therapeutic target in neurofibromatosis type 1-related pain that is reversed by (S)-Lacosamide
Abstract Neurofibromatosis type 1 (NF1) is a rare autosomal dominant disease linked to mutations of the Nf1 gene. Patients with NF1 commonly experience severe pain. Studies on mice with Nf1 haploinsufficiency have been instructive in identifying sensitization of ion channels as a possible cause underlying the heightened pain suffered by patients with NF1. However, behavioral assessments of Nf1+/− mice have led to uncertain conclusions about the potential causal role of Nf1 in pain. We used the clustered regularly interspaced short palindromic repeats (CRISPR)-associated 9 (CRISPR/Cas9) genome editing system to crea...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Research Paper Source Type: research

Discovery of endogenous opioid systems: what it has meant for the clinician's understanding of pain and its treatment
Abstract Before the discovery of the endogenous opioid system in the 1970s, opioids were understood only through the lens of opioid drug effects. Opium produced sleep, pain relief, and addiction. Once a variety of opioids had been extracted from opium, and still others synthesized chemically, it became clear that there must be endogenous receptors to explain differential drug effects. So, the search was on to identify the receptors, and subsequently their endogenous ligands. Even then, the consequential ways in which the endogenous opioid system influences the way we respond to the environment and survive took time to un...
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Pain Classics Source Type: research

Peripheral afferents and spinal inhibitory system in dynamic and static mechanical allodynia
No abstract available (Source: Pain)
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Topical Review Source Type: research

Hijacking the endogenous opioid system to treat pain: who thought it would be so complicated?
No abstract available (Source: Pain)
Source: Pain - November 21, 2017 Category: Anesthesiology Tags: Commentaries Source Type: research