Reply to Sun et al.
No abstract available (Source: Pain)
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Anti-inflammatory drugs with more penetration into the central nervous system may contribute to the treatment of trigeminal neuralgia
No abstract available (Source: Pain)
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Effects of open-label placebo on pain, functional disability, and spine mobility in patients with chronic back pain: a randomized controlled trial
Chronic back pain (CBP) is a major global health problem, while its treatment is hampered by a lack of efficacy and restricted safety profile of common frontline therapies. The present trial aims to determine whether a 3-week open-label placebo treatment reduces pain intensity and subjective and objective functional disability in patients with CBP. This randomized controlled trial, following a pretest–posttest design, enrolled 127 patients with CBP (pain duration>12 weeks) from the Back Pain Center, Neurology, University Hospital Essen, Germany. Patients randomized to the open-label placebo group received a 3-week...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Cell-specific role of histone deacetylase 6 in chemotherapy-induced mechanical allodynia and loss of intraepidermal nerve fibers
Chemotherapy-induced peripheral neuropathy (CIPN) is a serious adverse side effect of cancer treatment with no Food and Drug Administration-approved medication for its prevention or management. Using RNA sequencing analysis of dorsal root ganglia (DRG), we identify critical contributions of histone deacetylase 6 (HDAC6) and mitochondrial damage to the establishment of CIPN in a mouse model of cisplatin-induced neuropathy. We show that pharmacological inhibition of HDAC6 using ACY-1215 or global deletion of HDAC6 is sufficient to prevent cisplatin-induced mechanical allodynia, loss of intraepidermal nerve fibers (IENFs), an...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Recurrent low back pain patients demonstrate facilitated pronociceptive mechanisms when in pain, and impaired antinociceptive mechanisms with and without pain
This study investigated pronociceptive and antinociceptive mechanisms in recurrent LBP (RLBP) patients across painful and pain-free periods, compared with age/sex-matched asymptomatic controls. During a painful episode (day 0) and when pain-free (day 28), 30 RLBP patients were assessed and compared with 30 controls over the same timeframe. Pressure pain thresholds were recorded bilaterally on the arm, back, and leg. Cuff algometry was used to assess cuff pressure pain detection threshold and cuff pain tolerance threshold on the lower legs, as well as temporal summation of pain (10 repeated painful cuff test stimuli on the ...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Autoantibodies produce pain in complex regional pain syndrome by sensitizing nociceptors
Complex regional pain syndrome (CRPS) is a posttraumatic pain condition with an incompletely understood pathophysiological basis. Here, we have examined the cellular basis of pain in CRPS using behavioral and electrophysiological methods in mice treated with IgG from CRPS patients, in combination with a paw incision. Mice were subjected to a hind paw skin–muscle incision alone, or in combination with administration of IgG purified from either healthy control subjects or patients with persistent CRPS. Nociceptive function was examined behaviorally in vivo, and electrophysiologically in vitro using skin–nerve pre...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Paracetamol is ineffective for acute low back pain even for patients who comply with treatment: complier average causal effect analysis of a randomized controlled trial
In 2014, the Paracetamol for Acute Low Back Pain (PACE) trial demonstrated that paracetamol had no effect compared with placebo in acute low back pain (LBP). However, noncompliance was a potential limitation of this trial. The aim of this study was to investigate the efficacy of paracetamol in acute LBP among compliers. Using individual participant data from the PACE trial (ACTN12609000966291), complier average causal effect (CACE), intention-to-treat, and per protocol estimates were calculated for pain intensity (primary), disability, global rating of symptom change, and function (all secondary) after 2 weeks of follow-up...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Daily and bidirectional linkages between pain catastrophizing and spouse responses
Pain catastrophizing has been shown to predict greater pain and less physical function in daily life for chronic pain sufferers, but its effects on close social partners have received much less attention. The overall purpose of this study was to examine the extent to which pain catastrophizing is an interpersonal coping strategy that is maladaptive for patients and their spouses. A total of 144 older knee osteoarthritis patients and their spouses completed baseline interviews and a 22-day diary assessment. Multilevel lagged models indicated that, on days when patients reported greater catastrophizing in the morning, their ...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Whole-brain functional network disruption in chronic pain with disk herniation
Brain functional network properties are globally disrupted in multiple musculoskeletal chronic pain conditions. Back pain with lumbar disk herniation (LDH) is highly prevalent and a major route for progression to chronic back pain. However, brain functional network properties remain unknown in such patients. Here, we examined resting-state functional magnetic resonance imaging-based functional connectivity networks in chronic back pain patients with clear evidence for LDH (LDH-chronic pain n = 146), in comparison to healthy controls (HCs, n = 165). The study was conducted in China, thus providing the opportunity to also ex...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Withdrawal from an opioid induces a transferable memory trace in the cerebrospinal fluid
Opioids are the most powerful analgesics available to date. However, they may also induce adverse effects including paradoxical opioid-induced hyperalgesia. A mechanism that might underlie opioid-induced hyperalgesia is the amplification of synaptic strength at spinal C-fibre synapses after withdrawal from systemic opioids such as remifentanil (“opioid-withdrawal long-term potentiation [LTP]”). Here, we show that both the induction as well as the maintenance of opioid-withdrawal LTP were abolished by pharmacological blockade of spinal glial cells. By contrast, the blockade of TLR4 had no effect on the induction...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Perceptual and motor responses directly and indirectly mediate the effects of noxious stimuli on autonomic responses
Autonomic responses are an essential component of pain. They serve its adaptive function by regulating homeostasis and providing resources for protective and recuperative responses to noxious stimuli. To be adaptive and flexible, autonomic responses are not only determined by noxious stimulus characteristics, but likely also shaped by perceptual and motor responses to noxious stimuli. However, it is not fully known how noxious stimulus characteristics, perceptual responses, and motor responses interact in shaping autonomic responses. To address this question, we collected perceptual, motor, and autonomic responses to brief...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

A potential role for T-type calcium channels in homocysteinemia-induced peripheral neuropathy
Homocysteinemia is a metabolic condition characterized by abnormally high level of homocysteine in the blood and is considered to be a risk factor for peripheral neuropathy. However, the cellular mechanisms underlying toxic effects of homocysteine on the processing of peripheral nociception have not yet been investigated comprehensively. Here, using a rodent model of experimental homocysteinemia, we report the causal association between homocysteine and the development of mechanical allodynia. Homocysteinemia-induced mechanical allodynia was reversed on pharmacological inhibition of T-type calcium channels. In addition, ou...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Essential key messages about diagnosis, imaging, and self-care for people with low back pain: a modified Delphi study of consumer and expert opinions
People with back pain regularly search for information online; however, the quality of this online information is often poor. We established a list of the most important messages about diagnosis, imaging, and self-care for people with low back pain, based on consensus opinion and prioritised in order of importance. A list of key messages was derived from clinical practice guidelines for back pain. During 2 survey rounds, a Delphi panel of consumers with back pain and experts rated the importance of each item and suggested additional statements. Messages were retained that were rated as important by more than 70% of the pan...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Dynamic functional connectivity of the migraine brain: a resting-state functional magnetic resonance imaging study
Migraine headache is an episodic phenomenon, and patients with episodic migraine have ictal (headache), peri-ictal (premonitory, aura, and postdrome), and interictal (asymptomatic) phases. We aimed to find the functional characteristics of the migraine brain regardless of headache phase using dynamic functional connectivity analysis. We prospectively recruited 50 patients with migraine and 50 age- and sex-matched controls. All subjects underwent a resting-state functional magnetic resonance imaging. Significant networks were defined in a data-driven fashion from the interictal (>48 hours apart from headache phases) pati...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Heme and sensory neuropathy: insights from novel mutations in the heme exporter feline leukemia virus subgroup C receptor 1
Hereditary sensory and autonomic neuropathies (HSANs) are a group of clinically and genetically heterogeneous disorders of the peripheral nervous system mainly characterized by impaired nociception and autonomic dysfunction. We previously identified heme metabolism as a novel pathway contributing to sensory neurons maintenance and nociception. Indeed, we reported mutations in the feline leukemia virus subgroup C receptor 1 (FLVCR1) gene in individuals affected by HSAN. FLVCR1 gene encodes for 2 heme export proteins, FLVCR1a (plasma membrane) and FLVCR1b (mitochondria), crucially involved in the regulation of cellular heme ...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Brain dysfunction in chronic pain patients assessed by resting-state electroencephalography
Chronic pain is a common and severely disabling disease whose treatment is often unsatisfactory. Insights into the brain mechanisms of chronic pain promise to advance the understanding of the underlying pathophysiology and might help to develop disease markers and novel treatments. Here, we systematically exploited the potential of electroencephalography to determine abnormalities of brain function during the resting state in chronic pain. To this end, we performed state-of-the-art analyses of oscillatory brain activity, brain connectivity, and brain networks in 101 patients of either sex suffering from chronic pain. The r...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Motor simulation is disturbed when experiencing pain
While the contribution of social processes to pain perception is well documented, surprisingly little is known about the influence of pain on social perception. In particular, an important question is how pain modulates the processing of other people's actions. To address this question, the current study tests, using automatic imitation, the hypothesis that pain interferes with motor simulation—that is, the processing of observed actions in the motor system. Participants in both experiments performed an automatic imitation task requiring them to abduct their index or little finger while they saw someone else performi...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Fatty acid suppression of glial activation prevents central neuropathic pain after spinal cord injury
About half of patients with spinal cord injury (SCI) develop debilitating central neuropathic pain (CNP), with no effective treatments. Thus, effective, safe, and novel therapies are needed urgently. Previously, docosahexaenoic acid (DHA) was reported to confer neuroprotection in preclinical SCI models. However, its therapeutic potential on SCI-CNP remains to be elucidated. Here, we demonstrated for the first time that intravenous DHA administrations with 3-day intervals (250 nmol/kg; starting 30 minutes after injury and maintained for 6 weeks) effectively prevented SCI-CNP development in a clinically relevant rat contusio...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Dermorphin [D-Arg2, Lys4] (1-4) amide inhibits below-level heat hypersensitivity in mice after contusive thoracic spinal cord injury
We examined whether activating mu-opioid receptors (MORs) in the peripheral nervous system attenuates spinal cord injury (SCI) pain-like behavior in mice. We produced a contusive SCI at the T10 vertebral level and examined motor and sensory dysfunction for 6 weeks. At 6 weeks, we tested the effect of subcutaneous (s.c.) injection of dermorphin [D-Arg2, Lys4] (1-4) amide (DALDA), a peripherally acting MOR-preferring agonist, on mechanical and heat hypersensitivity. Basso mouse scale score was significantly decreased after SCI, and mice showed hypersensitivity to mechanical and heat stimulation at the hind paw beginning at 2...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Epidermal expression of human TRPM8, but not of TRPA1 ion channels, is associated with sensory responses to local skin cooling
Human cold perception and nociception play an important role in persisting pain. However, species differences in the target temperature of thermosensitive ion channels expressed in peripheral nerve endings have fueled discussions about the mechanism of cold nociception in humans. Most frequently implicated thermosensors are members of the transient receptor potential (TRP) ion channel family TRPM8 and TRPA1. Regularly observed, distinct cold pain phenotype groups suggested the existence of interindividually differing molecular bases. In 28 subjects displaying either high or medium sensitivity to local cooling of the skin, ...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

A randomized pilot study to investigate the effect of opioids on immunomarkers using gene expression profiling during surgery
Endogenous opioid peptides and exogenous opioids modulate immune function, and animal and human studies have shown that some have a depressant immunomodulatory effect. This is potentially of high clinical significance, eg, in cancer patients and surgery. The primary objective of this pilot study was to evaluate the effect of morphine and oxycodone on immune pathways associated with immunosuppression in gynecological laparotomy patients. Gene expression was analyzed in CD4+, CD8+, and natural killer (NK) cells using the 3′ Affymetrix microarray. Patients were randomized to receive morphine, oxycodone, or nonopioid &ld...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Conditioned pain modulation as a biomarker of chronic pain: a systematic review of its concurrent validity
Conditioned pain modulation (CPM) is a promising psychophysical biomarker of central pain mechanisms because it significantly discriminates patients with chronic pain from healthy controls. Nevertheless, it is unclear in what extent CPM assessed experimentally is correlated with clinical manifestations of pain. To assess the concurrent validity of CPM, we performed a systematic review of the literature reporting correlations between CPM responses and pain intensity, disability, duration, and area in patients with different chronic pain conditions. We included 32 studies that altogether encompassed data from 1958 patients a...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Systematic Review and Meta-Analysis Source Type: research

Itch sensitization? A systematic review of studies using quantitative sensory testing in patients with chronic itch
As well established for patients with chronic pain, patients suffering from chronic itch also exhibit signs of peripheral and central sensitization. This has been linked to parallel neuroplastic sensitization processes. However, for chronic itch, sensitization has not yet been systematically assessed, studied, and hence validated. This review (Prospero CRD42016043002) summarizes and meta-analytically evaluates whether sensory aberrations including sensitization for itch occur in chronic itch. Databases PubMed, Embase, and Cochrane Library were searched for studies investigating somatosensory sensitivity assessment by quant...
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Systematic Review and Meta-Analysis Source Type: research

Refractory dependence on opioid analgesics
No abstract available (Source: Pain)
Source: Pain - November 19, 2019 Category: Anesthesiology Tags: Topical Review Source Type: research

Reply to Häuser et al.
No abstract available (Source: Pain)
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Fibromyalgia as a chronic primary pain syndrome: issues to discuss
No abstract available (Source: Pain)
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Cell type–specific super-resolution imaging reveals an increase in calcium-permeable AMPA receptors at spinal peptidergic terminals as an anatomical correlate of inflammatory pain
Spinal hyperexcitability is a key event in the development of persistent pain, and arises partly from alterations in the number and localization of α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA)-type glutamate receptors. However, determining precisely where these changes occur is challenging due to the requirement for multiplex labelling and nanoscale resolution. The recent development of super-resolution light microscopy provides new tools to address these challenges. Here, we apply combined confocal/direct STochastic Optical Reconstruction Microscopy (dSTORM) to reveal changes in calcium-permeable subunit...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Oxycodone, fentanyl, and morphine amplify established neuropathic pain in male rats
Opioids are widely prescribed for chronic pain, including neuropathic pain, despite growing evidence of long-term harm. Previous preclinical studies have documented exacerbation of nociceptive hypersensitivity, including that induced by peripheral nerve injury, by morphine. The present series of behavioral studies sought to replicate and extend our prior research, which demonstrated a multimonth exacerbation of nociceptive hypersensitivity by a 5-day course of morphine initiated 10 days after nerve injury. The current studies demonstrate that enduring exacerbation of nociceptive hypersensitivity is not restricted to morphi...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Repetitive transcranial magnetic stimulation of the primary motor cortex expedites recovery in the transition from acute to sustained experimental pain: a randomised, controlled study
This study investigated the effect of 5 consecutive days of excitatory M1 rTMS on pain, functional limitation, mechanical hyperalgesia, descending inhibitory pain control, and M1 organisation in the transition from acute to sustained pain. Thirty healthy participants attended 8 sessions over a 16-day period. On days 0, 2, and 4, nerve growth factor was injected into the right forearm to induce progressively developing muscle soreness and mechanical hyperalgesia. Active or sham excitatory rTMS was delivered on days 4 to 8. Clinical and neurophysiological outcomes were recorded on days 0, 2, 4, 6, 8, 11, and 14. Active rTMS ...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Trigeminal Aδ- and C-afferent supply of lamina I neurons in the trigeminocervical complex
In conclusion, the trigeminocervical lamina I neurons receive a complex pattern of long-range monosynaptic and polysynaptic inputs from a variety of the trigeminal nociceptive afferents. (Source: Pain)
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Cerebrospinal fluid biomarkers of inflammation in trigeminal neuralgia patients operated with microvascular decompression
Compression of the trigeminal root entry zone by a blood vessel can cause trigeminal neuralgia (TN). However, a neurovascular conflict does not explain all cases of TN, and TN can exist without a neurovascular contact. A common observation during microvascular decompression surgery to treat TN is arachnoiditis in the region of the trigeminal nerve. Thus, aberrant inflammatory mechanisms may be involved in the pathophysiology of TN but information about the role of inflammation in TN is scarce. We used Proximity Extension Assay technology to analyse the levels of 92 protein biomarkers related to inflammation in lumbar cereb...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Altered microbiome composition in individuals with fibromyalgia
Fibromyalgia (FM) is a prevalent syndrome, characterised by chronic widespread pain, fatigue, and impaired sleep, that is challenging to diagnose and difficult to treat. The microbiomes of 77 women with FM and that of 79 control participants were compared using 16S rRNA gene amplification and whole-genome sequencing. When comparing FM patients with unrelated controls using differential abundance analysis, significant differences were revealed in several bacterial taxa. Variance in the composition of the microbiomes was explained by FM-related variables more than by any other innate or environmental variable and correlated ...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Sustained efficacy of kangaroo care for repeated painful procedures over neonatal intensive care unit hospitalization: a single-blind randomized controlled trial
Preterm neonates hospitalized in the neonatal intensive care unit undergo frequent painful procedures daily, often without pain treatment, with associated long-term adverse effects. Maternal-infant skin-to-skin contact, or kangaroo care (KC), and sweet-tasting solutions such as sucrose are effective strategies to reduce pain during a single procedure; however, evidence of sustained efficacy over repeated procedures is limited. We aimed to determine the relative sustained efficacy of maternal KC, administered alone or in combination with 24% sucrose, to reduce behavioral pain intensity associated with routine neonatal proce...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Linaclotide treatment reduces endometriosis-associated vaginal hyperalgesia and mechanical allodynia through viscerovisceral cross-talk
Endometriosis, an estrogen-dependent chronic inflammatory disease, is the most common cause of chronic pelvic pain. Here, we investigated the effects of linaclotide, a Food and Drug Administration–approved treatment for IBS-C, in a rat model of endometriosis. Eight weeks after endometrium transplantation into the intestinal mesentery, rats developed endometrial lesions as well as vaginal hyperalgesia to distension and decreased mechanical hind paw withdrawal thresholds. Daily oral administration of linaclotide, a peripherally restricted guanylate cyclase-C (GC-C) agonist peptide acting locally within the gastrointest...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

A randomised, double-blind, placebo-controlled crossover trial of the influence of the HCN channel blocker ivabradine in a healthy volunteer pain model: an enriched population trial
Preclinical studies suggest that type 2 hyperpolarization-activated cyclic nucleotide gated ion channels (HCN2) are necessary for neuropathic pain. This trial assessed the influence of ivabradine, a nonselective HCN channel blocker, on capsaicin-induced hyperalgesia and pain in healthy human subjects. An enriched population comprising subjects who developed>20 cm2 of punctate hyperalgesia from topical capsaicin (0.5% cream applied onto 9 cm2 area) was identified. These subjects then received ivabradine (15 mg) or placebo 1 hour before capsaicin application in randomly allocated order in a crossover study. The forearm si...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Testing the intergenerational model of transmission of risk for chronic pain from parents to their children: an empirical investigation of social transmission pathways
Children of parents with chronic pain have higher rates of pain and internalizing (eg, anxiety and depressive) symptoms than children of parents without chronic pain. Parental modeling of pain behaviour and reinforcement of child pain have been hypothesized to underlie these relationships. These mechanisms were tested in a sample of 72 parents with chronic pain and their children (aged 8-15 years). Standardized measures were completed by parents (pain characteristics, pain interference, and child internalizing) and children (pain catastrophizing, pain over previous 3 months, and internalizing). In a laboratory session, chi...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Assessing pain in critically ill brain-injured patients: a psychometric comparison of 3 pain scales and videopupillometry
In conclusion, the BPS, NCS-I, and NCS-R-I are valid, reliable, and acceptable pain scales for use in intubated critically ill, brain-injured patients, unlike videopupillometry. Future research requires tool design centered on domains of observation adapted to this very specific population. (Source: Pain)
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

The rostromedial tegmental nucleus: a key modulator of pain and opioid analgesia
In this study, multiplexing of GABAergic neurons in the RMTg was achieved using stimulatory Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) and inhibitory kappa-opioid receptor DREADDs (KORD). Our data show that locally infused RMTg morphine or selective RMTg GABAergic neuron inhibition produces 87% of the maximal antinociceptive effect of systemic morphine, and RMTg GABAergic neurons modulate dopamine release in the nucleus accumbens. In addition, chemoactivation of VTA dopamine neurons significantly reduced pain behaviors both in resting and facilitated pain states and reduced by 75% the dose of syst...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

A randomized controlled efficacy trial of mindfulness-based stress reduction compared with an active control group and usual care for fibromyalgia: the EUDAIMON study
This study examined the efficacy of mindfulness-based stress reduction (MBSR) for reducing functional impairment as well as the role of mindfulness-related constructs as mediators of treatment outcomes for people with FM. Two hundred twenty-five participants with FM were randomized into 3 study arms: MBSR plus treatment-as-usual (TAU), FibroQoL (multicomponent intervention for FM) plus TAU, and TAU alone. The primary endpoint was functional impact (measured with the Fibromyalgia Impact Questionnaire Revised), and secondary outcomes included “fibromyalginess,” anxiety and depression, pain catastrophising, percei...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Methylglyoxal causes pain and hyperalgesia in human through C-fiber activation
In conclusion, the actions of MG through TRPA1 activation on predominantly mechano-insensitive C fibers might be involved in spontaneously perceived pain in diabetic neuropathy and hyperalgesia as well as allodynia. (Source: Pain)
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

The glutamate to γ-aminobutyric acid ratio in the posterior insula is associated with pain perception in healthy women but not in women with borderline personality disorder
In conclusion, the study showed that individual differences in pain perception may in part be explained by the individual glutamate/GABA ratio in the posterior insula. However, this possible mechanism does not explain the differences in pain perception between BPD patients and HCs. (Source: Pain)
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Assessment of nociception and related quality-of-life measures in a porcine model of neurofibromatosis type 1
We present the first characterization of pain-related behaviors in a pig model of NF1, identifying unchanged agitation scores, lower tactile thresholds (allodynia), and decreased response latencies to thermal laser stimulation (hyperalgesia) in NF1+/ex42del (females only) pigs. Male NF1+/ex42del pigs with tumors showed reduced sleep quality and increased resting, 2 health-related quality-of-life symptoms found to be comorbid in people with NF1 pain. We explore these phenotypes in relationship to suppression of the increased activity of the N-type voltage-gated calcium (CaV2.2) channel by pharmacological antagonism of phosp...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Associations of mental health and family background with opioid analgesic therapy: a nationwide Swedish register-based study
This study estimated associations of diverse preexisting mental health diagnoses, parental mental health history, and SES in childhood with opioid analgesic prescription patterns nationwide in Sweden. Using register-based data, we identified 5,071,193 (48.4% female) adolescents and adults who were naive to prescription opioid analgesics and followed them from 2007 to 2014. The cumulative incidence of any dispensed opioid analgesic within 3 years was 11.4% (95% CI, 11.3%-11.4%). Individuals with preexisting self-injurious behavior, as well as opioid and other substance use, attention-deficit/hyperactivity, depressive, anxie...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

A randomized trial to assess the immediate impact of acupuncture on quantitative sensory testing, pain, and functional status
In this randomized clinical trial, we examined whether the effect of true acupuncture can be differentiated from sham acupuncture (pain and functionality) by analyzing quantitative sensory testing (QST) profiles in chronic pain participants. We recruited 254 healthy or chronic back and neck pain participants. Healthy subjects were included to control for a possible effect of acupuncture on baseline QST changes. Study participants received 6 sessions (twice weekly) of true acupuncture, sham acupuncture, or no acupuncture treatment (routine care). Quantitative sensory testing profiles, pain scores, and functionality profile ...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Sham surgeries for central and peripheral neural injuries persistently enhance pain-avoidance behavior as revealed by an operant conflict test
Studies using rodent models of neuropathic pain use sham surgery control procedures that cause deep tissue damage. Sham surgeries would thus be expected to induce potentially long-lasting postsurgical pain, but little evidence for such pain has been reported. Operant tests of voluntary behavior can reveal negative motivational and cognitive aspects of pain that may provide sensitive tools for detecting pain-related alterations. In a previously described operant mechanical conflict test involving lengthy familiarization and training, rodents freely choose to either escape from a brightly lit chamber by crossing sharp probes...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Family history of pain and risk of musculoskeletal pain in children and adolescents: a systematic review and meta-analysis
Emerging evidence suggests that musculoskeletal (MSK) pain should be viewed from a biopsychosocial perspective and consider the influence of family factors. We conducted a review with meta-analysis to provide summary estimates of effect of family history of pain on childhood MSK pain and explore whether specific family pain factors influence the strength of the association (PROSPERO CRD42018090130). Included studies reported associations between family history of pain and nonspecific MSK pain in children (age (Source: Pain)
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Systematic Review and Meta-Analysis Source Type: research

Investigating intraindividual pain variability: methods, applications, issues, and directions
Pain is a dynamic experience subject to substantial individual differences. Intensive longitudinal designs best capture the dynamical ebb and flow of the pain experience across time and settings. Thanks to the development of innovative and efficient data collection technologies, conducting an intensive longitudinal pain study has become increasingly feasible. However, the majority of longitudinal studies have tended to examine average level of pain as a predictor or as an outcome, while conceptualizing intraindividual pain variation as noise, error, or a nuisance factor. Such an approach may miss the opportunity to underst...
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Comprehensive Review Source Type: research

Acute neuropathic pain: equivalent or different to chronic neuropathic pain? A call for gathering of scientifically based information on acute neuropathic pain
No abstract available (Source: Pain)
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Perspective Source Type: research

Indices of pain variability: a paradigm shift
No abstract available (Source: Pain)
Source: Pain - October 24, 2019 Category: Anesthesiology Tags: Commentary Source Type: research

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