Nerve growth factor inhibitors for low back pain: balancing the risks and benefits
No abstract available (Source: Pain)
Source: Pain - August 20, 2020 Category: Anesthesiology Tags: Commentary Source Type: research

Reply to Banik
No abstract available (Source: Pain)
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Correspondence Source Type: research

Therapeutic benefits of placebo surgery and challenges in neuromodulation research
No abstract available (Source: Pain)
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Correspondence Source Type: research

High postoperative pain intensity and analgesic requirements: are they caused by remifentanil or inadequate analgesia?
No abstract available (Source: Pain)
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Correspondence Source Type: research

Localized sympathectomy reduces peripheral nerve regeneration and pain behaviors in 2 rat neuropathic pain models
This study examined reduction in peripheral nerve regeneration as one possible mechanism for relief of neuropathic pain by sympathetic blockade. A “microsympathectomy,” consisting of cutting the gray rami containing sympathetic postganglionic axons where they enter the L4 and L5 spinal nerves, reduced mechanical hypersensitivity in 2 different rat neuropathic pain models. In the spinal nerve ligation model, in which some functional regeneration and reinnervation of the ligated spinal nerve can be observed, microsympathectomy reduced functional and anatomical measures of regeneration as well as expression of gro...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Postnatal maturation of spinal dynorphin circuits and their role in somatosensation
Inhibitory interneurons in the adult spinal dorsal horn (DH) can be neurochemically classified into subpopulations that regulate distinct somatosensory modalities. Although inhibitory networks in the rodent DH undergo dramatic remodeling over the first weeks of life, little is known about the maturation of identified classes of GABAergic interneurons, or whether their role in somatosensation shifts during development. We investigated age-dependent changes in the connectivity and function of prodynorphin (DYN)-lineage neurons in the mouse DH that suppress mechanosensation and itch during adulthood. In vitro patch clamp reco...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

The impact of bone cancer on the peripheral encoding of mechanical pressure stimuli
Skeletal metastases are frequently accompanied by chronic pain that is mechanoceptive in nature. Mechanistically, cancer-induced bone pain (CIBP) is mediated by peripheral sensory neurons innervating the cancerous site, the cell bodies of which are housed in the dorsal root ganglia (DRG). How these somatosensory neurons encode sensory information in CIBP remains only partly explained. Using a validated rat model, we first confirmed cortical bone destruction in CIBP but not sham-operated rats (day 14 after surgery, designated “late”-stage bone cancer). This occurred with behavioural mechanical hypersensitivity (...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Attention to breath sensations does not engage endogenous opioids to reduce pain
The endogenous opioidergic system is critically involved in the cognitive modulation of pain. Slow-breathing-based techniques are widely used nonpharmacological approaches to reduce pain. Yet, the active mechanisms of actions supporting these practices are poorly characterized. Growing evidence suggest that mindfulness-meditation, a slow-breathing technique practiced by nonreactively attending to breathing sensations, engages multiple unique neural mechanisms that bypass opioidergically mediated descending pathways to reduce pain. However, it is unknown whether endogenous opioids contribute to pain reductions produced by s...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Placebo hypoalgesia: racial differences
No large-cohort studies that examine potential racial effects on placebo hypoalgesic effects exist. To fill this void, we studied placebo effects in healthy and chronic pain participants self-identified as either African American/black (AA/black) or white. We enrolled 372 study participants, 186 with a diagnosis of temporomandibular disorder (TMD) and 186 race-, sex-, and age-matched healthy participants to participate in a placebo experiment. Using a well-established paradigm of classical conditioning with verbal suggestions, each individual pain sensitivity was measured to calibrate the temperatures for high- and low-pai...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Sex differences in the development of anxiodepressive-like behavior of mice subjected to sciatic nerve cuffing
We investigated the contribution of nucleus locus ceruleus (LC) to the development of pain-associated affective behavior. Mice of both sexes were subjected to sciatic nerve cuffing, a model of peripheral nerve injury, and monitored for 45 days. Although the thermal and mechanical thresholds were equally decreased in both males and females, only the male mice developed anxiodepressive-like behavior, which was complemented by suppressed hippocampal neurogenesis. Furthermore, the LC activity was lower in males when compared with females subjected to sciatic cuffing. Next, we used a chemogenetic approach to modulate the activi...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Individual variability and sex differences in conditioned pain modulation and the impact of resilience, and conditioning stimulus pain unpleasantness and salience
Distinct pain experiences are shaped both by personal attributes and characteristics of noxious stimuli. An Individual's capacity for endogenous pain inhibition (reflected by conditioned pain modulation [CPM]), their resilience, and the pain unpleasantness and salience of painful stimuli can impact their pain perception. Here, we aimed to determine how individual variability in CPM relates to sex and resilience as personal attributes, and pain unpleasantness and salience of the CPM conditioning stimulus (CS). We evaluated CPM in 106 healthy participants (51 female and 55 male) based on the change in test stimulus pain appl...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Enhanced mindfulness-based stress reduction in episodic migraine: a randomized clinical trial with magnetic resonance imaging outcomes
We aimed to evaluate the efficacy of an enhanced mindfulness-based stress reduction (MBSR+) vs stress management for headache (SMH). We performed a randomized, assessor-blind, clinical trial of 98 adults with episodic migraine recruited at a single academic center comparing MBSR+ (n = 50) with SMH (n = 48). MBSR+ and SMH were delivered weekly by group for 8 weeks, then biweekly for another 8 weeks. The primary clinical outcome was reduction in headache days from baseline to 20 weeks. Magnetic resonance imaging (MRI) outcomes included activity of left dorsolateral prefrontal cortex (DLPFC) and cognitive task network during ...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Hippocampal glutamatergic synapses impairment mediated novel-object recognition dysfunction in rats with neuropathic pain
In this study, we adopted the spared nerve injury model to establish the progress of chronic pain and investigated the mechanism underlying the cognitive aspect related to it. At behavioral level, using the novel-object recognition test, mechanical hypersensitivity was observed in peripheral nerve-injured rats because they exhibited recognition deficits. We showed a dramatic decrease in hippocampal glutamate concentration using nuclear magnetic resonance and reduced glutamatergic synaptic transmission using whole-cell recordings. These were associated with deficient hippocampal long-term potentiation induced by high-freque...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Physical disuse contributes to widespread chronic mechanical hyperalgesia, tactile allodynia, and cold allodynia through neurogenic inflammation and spino-parabrachio-amygdaloid pathway activation
In this study, we also demonstrated dystrophy-like changes, both peripheral nociceptive signals and activation of the central pain pathway in CPCP rats. This was done by the following methods: (1) vascular permeability (Evans blue dye) and inflammatory- and oxidative stress-related messenger RNA changes (real-time quantitative polymerase chain reaction); (2) immunofluorescence of pERK and/or c-Fos expression in the spino-parabrachio-amygdaloid pathway; and (3) blockade of nociceptive-related signals using sciatic nerve block. Furthermore, we demonstrated tactile allodynia using an optogenetic method in a transgenic rat lin...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Heat shock protein 90 inhibitors block the antinociceptive effects of opioids in mouse chemotherapy-induced neuropathy and cancer bone pain models
This study extended from that initial work to test the cancer-related clinical impact of Hsp90 inhibitors on opioid antinociception in cancer-induced bone pain in female BALB/c mice and chemotherapy-induced peripheral neuropathy in male and female CD-1 mice. Mice were treated with Hsp90 inhibitors (17-AAG, KU-32) by the intracerebroventricular, intrathecal, or intraperitoneal routes, and after 24 hours, pain behaviors were evaluated after analgesic drug treatment. Heat shock protein 90 inhibition in the brain or systemically completely blocked morphine and oxymorphone antinociception in chemotherapy-induced peripheral neur...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Structural abnormalities in the temporalis musculo-aponeurotic complex in chronic muscular temporomandibular disorders
Some forms of chronic pain are thought to be driven and maintained by nociceptive input, which can drive plasticity within nociceptive pathways. We have previously identified abnormalities along the entire nociceptive pathway in chronic myalgic temporomandibular disorders (mTMD), including the trigeminal nerves, brainstem pathways, and in the thalamus and somatosensory cortex. These data suggest that there is a peripheral nociceptive drive in mTMD, but the source of this nociceptive activity remains unknown. Here, our aim was to determine whether structural abnormalities exist in the muscles of mastication of patients with...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Gender differences in attention to pain body postures in a social context: a novel use of the bodies in the crowd task
Pain signals the presence of potential harm, captures attention, and can inhibit performance on concurrent tasks. What is less well known, however, is whether such attentional capture also occurs in a wider social context, such as when observing people in pain. To explore this possibility, we adopted a novel social-cue detection methodology: the bodies-in-the-crowd task. Two experiments are reported that consider whether nonverbal cues of pain, happiness, and anger as expressed through body postures would capture and hold attention. Both experiments recruited 40 (20 male and 20 female) pain-free individuals. Overall, resul...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Increasing gender differences in the prevalence and chronification of orofacial pain in the population
Although a fluctuating pattern of orofacial pain across the life span has been proposed, data on its natural course are lacking. The longitudinal course of orofacial pain in the general population was evaluated using data from routine dental check-ups at all Public Dental Health services in Västerbotten, Sweden. In a large population sample, 2 screening questions were used to identify individuals with pain once a week or more in the orofacial area. Incidence and longitudinal course of orofacial pain were evaluated using annual data for 2010 to 2017. To evaluate predictors for orofacial pain remaining over time, indivi...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Efficacy and safety of propranolol for treatment of temporomandibular disorder pain: a randomized, placebo-controlled clinical trial
Propranolol is a nonselective beta-adrenergic receptor antagonist. A multicenter, randomized, double-blind, placebo-controlled, parallel-group, phase 2b trial enrolled participants aged 18 to 65 years with temporomandibular disorder myalgia to evaluate efficacy and safety of propranolol compared with placebo in reducing facial pain. Participants were randomized 1:1 to either extended-release propranolol hydrochloride (60 mg, BID) or placebo. The primary endpoint was change in facial pain index (FPI = facial pain intensity multiplied by facial pain duration, divided by 100). Efficacy was analyzed as a mean change in FPI fro...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Transcribed ultraconserved noncoding RNA uc.153 is a new player in neuropathic pain
Transcribed ultraconserved regions are a novel class of long noncoding RNAs and are completely conserved in humans, rats, and mice. Transcribed ultraconserved regions have been implicated in diverse biological processes; however, very little is currently known about their role in pain modulation. Here, we found that the level of the spinal transcribed ultraconserved region uc.153 was significantly increased in a mouse model of sciatic nerve chronic constriction injury (CCI)-induced chronic neuropathic pain. The knockdown of spinal uc.153 prevented and reversed chronic constriction injury–induced pain behaviours and s...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Regulatory T cells counteract neuropathic pain through inhibition of the Th1 response at the site of peripheral nerve injury
In conclusion, the boosting of Treg cell function/activity might be explored as a possible interventional approach to reduce neuropathic pain development after peripheral nerve damage. (Source: Pain)
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Molecular, circuit, and anatomical changes in the prefrontal cortex in chronic pain
No abstract available (Source: Pain)
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: PAIN Pictured Source Type: research

“No one wants to look after the fibro patient”. Understanding models, and patient perspectives, of care for fibromyalgia: reviews of current evidence
Fibromyalgia is a common and complex long-term pain condition. Despite advancements in our understanding and treatment of fibromyalgia, patients report patchy health care provision and frustrating journeys through the health care system. To inform how best to deliver care, we undertook 2 narrative reviews examining existing evidence on (1) models of care for fibromyalgia and (2) patients' experiences, preferences, and unmet needs regarding their health care. Seven databases were systematically searched. Quantitative data was narratively synthesised and qualitative data thematically analysed. No evidence-based model of care...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Narrative Review Source Type: research

Patients' experience with and perspectives on neuromodulation for pain: a systematic review of the qualitative research literature
Chronic pain has far-reaching impacts on a person's life and on society more broadly. After failure or intolerance of conservative treatments, neuromodulation may be an option for a subgroup of patients. However, little is known about the patient experience of neuromodulation. We conducted a systematic review of published qualitative research on patient experience with neuromodulation for chronic pain. Four databases were searched: MEDLINE, EMBASE, Psych INFO, and all EMB reviews, from inception to December 4, 2019. We used narrative synthesis to identify key findings from the included studies. The data were qualitatively ...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Systematic Review and Meta-Analysis Source Type: research

The efficacy of mindfulness-based interventions in acute pain: a systematic review and meta-analysis
Recent meta-analyses have shown mindfulness-based interventions (MBIs) to be effective for chronic pain, but no pooled estimates of the effect of MBIs on acute pain are available. This meta-analysis was conducted to fill that gap. A literature search was conducted in 4 databases. Articles were eligible if they reported on randomized controlled trials of MBIs for people with acute pain and one of the following outcomes: pain severity, pain threshold, pain tolerance, or pain-related distress. Two authors independently extracted the data, assessed risk of bias, and provided GRADE ratings. Twenty-two studies were included. The...
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Systematic Review and Meta-Analysis Source Type: research

Considering the potential for an increase in chronic pain after the COVID-19 pandemic
No abstract available (Source: Pain)
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Topical Review Source Type: research

Pain, nicotine, and tobacco smoking: current state of the science
No abstract available (Source: Pain)
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Topical Review Source Type: research

The mindful migraine: does mindfulness-based stress reduction relieve episodic migraine?
No abstract available (Source: Pain)
Source: Pain - July 30, 2020 Category: Anesthesiology Tags: Commentary Source Type: research

Brain dysfunction in chronic pain patients assessed by resting-state electroencephalography: Erratum
No abstract available (Source: Pain)
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Erratum Source Type: research

Reply to Cohen and Murnion
No abstract available (Source: Pain)
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Correspondence Source Type: research

Does “dependence” on opioids constitute a distinct clinical state?
No abstract available (Source: Pain)
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Correspondence Source Type: research

PAC1 receptor blockade reduces central nociceptive activity: new approach for primary headache?
Pituitary adenylate cyclase activating polypeptide-38 (PACAP38) may play an important role in primary headaches. Preclinical evidence suggests that PACAP38 modulates trigeminal nociceptive activity mainly through PAC1 receptors while clinical studies report that plasma concentrations of PACAP38 are elevated in spontaneous attacks of cluster headache and migraine and normalize after treatment with sumatriptan. Intravenous infusion of PACAP38 induces migraine-like attacks in migraineurs and cluster-like attacks in cluster headache patients. A rodent-specific PAC1 receptor antibody Ab181 was developed, and its effect on nocic...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Vagus nerve stimulation inhibits cortical spreading depression exclusively through central mechanisms
Experimental and clinical data strongly support vagus nerve stimulation (VNS) as a novel treatment in migraine. Vagus nerve stimulation acutely suppresses cortical spreading depression (CSD) susceptibility, an experimental model that has been used to screen for migraine therapies. However, mechanisms underlying VNS efficacy on CSD are unknown. Here, we interrogated the central and peripheral mechanisms using VNS delivered either invasively (iVNS) or noninvasively (nVNS) in male Sprague-Dawley rats. Cortical spreading depression susceptibility was evaluated 40 minutes after the stimulation. iVNS elevated the electrical CSD ...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Differential modulation of excitatory and inhibitory populations of superficial dorsal horn neurons in lumbar spinal cord by Aβ-fiber electrical stimulation
Activation of Aβ-fibers is fundamental to numerous analgesic therapies, yet its effects on dorsal horn neuronal activity remain unclear. We used multiphoton microscopy of the genetically encoded calcium indicator GCaMP6s to characterize the effects of Aβ-fiber electrical stimulation (Aβ-ES) on neural activity. Specifically, we quantified somatic responses evoked by C-fiber intensity stimulation before and after a 10-minute train of dorsal root Aβ-ES in superficial dorsal horn (SDH) neurons, in mouse lumbar spinal cord. Aβ-ES did not alter C-fiber-evoked activity when GCaMP6s was virally expressed i...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Distribution of functional opioid receptors in human dorsal root ganglion neurons
Preclinical evidence has highlighted the importance of the μ-opioid peptide (MOP) receptor on primary afferents for both the analgesic actions of MOP receptor agonists, as well as the development of tolerance, if not opioid-induced hyperalgesia. There is also growing interest in targeting other opioid peptide receptor subtypes (δ-opioid peptide [DOP], κ-opioid peptide [KOP], and nociceptin/orphanin-FQ opioid peptide [NOP]) on primary afferents, as alternatives to MOP receptors, which may not be associated with as many deleterious side effects. Nevertheless, results from several recent studies of human sensor...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Almost 1 in 5 South African adults have chronic pain: a prevalence study conducted in a large nationally representative sample
This article presents the prevalence of chronic pain in the general population of a middle-income African country. These data give much needed insights into the burden of, and risk factors for, chronic pain in low-resource settings, and identify priority groups for intervention. (Source: Pain)
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Altered updating of bodily and spatial representations after tool-use in complex regional pain syndrome
Distorted representations of the body and peripersonal space are common in complex regional pain syndrome (CRPS), and might modulate its symptoms (eg, asymmetric limb temperature). In pain-free people, such representations are malleable, and update when we interact with objects in our environment (eg, during tool-use). Distortions are also common after immobilisation, but quickly normalise once movement is regained. We tested the hypothesis that people with CRPS have problems updating bodily and spatial representations, which contributes to the maintenance of their distorted representations by preventing normalization. We ...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Learning mechanisms in nocebo hyperalgesia: the role of conditioning and extinction processes
This study explored for the first time distinct nocebo conditioning methods and their consequences for nocebo attenuation methods. Healthy participants (N = 140) were recruited and randomized to the following nocebo hyperalgesia induction groups: conditioning with continuous reinforcement (CRF), conditioning with partial reinforcement (PRF), and a sham-conditioning control group. In the attenuation phase, counterconditioning was compared with extinction. During induction, participants experienced increased thermal pain in 100% of nocebo trials in the CRF groups, while in only 70% of nocebo trials in the PRF groups. During ...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Activation of EphB receptors contributes to primary sensory neuron excitability by facilitating Ca2+ influx directly or through Src kinase-mediated N-methyl-D-aspartate receptor phosphorylation
EphrinB-EphB receptor tyrosine kinases have been demonstrated to play important roles in pain processing after peripheral nerve injury. We have previously reported that ephrinB-EphB receptor signaling can regulate excitability and plasticity of neurons in spinal dorsal horn, and thus contribute to spinal central sensitization in neuropathic pain. How EphB receptor activation influences excitability of primary neurons in dorsal root ganglion (DRG), however, remains unknown. Here, we report that EphB receptor activation facilitates calcium influx through N-methyl-D-aspartate receptor (NMDAR) dependent and independent manners...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Pain-related behaviors associated with persistence of mechanical hyperalgesia after antigen-induced arthritis in rats
Upon transient musculoskeletal diseases, some patients develop persistent pain while others recover from pain. Here, we studied whether such heterogeneity also occurs in rats after recovery from unilateral antigen-induced arthritis (AIA) in the knee joint, and which pain phenotype may predict the course of pain. Typically, inflammatory swelling lasts about 3 weeks. Pain-related behaviors were monitored for 84 days after AIA induction. Unbiased cluster analysis of intragroup differences at day 84 of AIA revealed that about one-third of the rats (cluster 1) showed persistent mechanical hyperalgesia at the injected knee joint...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Early postoperative pain after laparoscopic donor nephrectomy predicts 30-day postoperative infectious complications: a pooled analysis of randomized controlled trials
Our research group recently published a positive association between early postoperative pain and 30-day postoperative complications in a broad surgical population. To investigate whether heterogeneity of the population and surgical procedures influenced these results, we explored this association in a homogenous surgical population. A secondary analysis of the LEOPARD-2 (clinicaltrials.gov NCT02146417) and RELAX-1 study (NCT02838134) in laparoscopic donor nephrectomy patients (n = 160) was performed. Pain scores on the postanesthesia care unit and postoperative day (POD) 1 and 2 were compared between patients with infecti...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Magnetic resonance imaging of neuroinflammation in chronic pain: a role for astrogliosis?
Noninvasive measures of neuroinflammatory processes in humans could substantially aid diagnosis and therapeutic development for many disorders, including chronic pain. Several proton magnetic resonance spectroscopy (1H-MRS) metabolites have been linked with glial activity (ie, choline and myo-inositol) and found to be altered in chronic pain patients, but their role in the neuroinflammatory cascade is not well known. Our multimodal study evaluated resting functional magnetic resonance imaging connectivity and 1H-MRS metabolite concentration in insula cortex in 43 patients suffering from fibromyalgia, a chronic centralized ...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Common transcriptional signatures of neuropathic pain
Abstarct The dorsal root ganglia (DRG) are key structures in nociception and chronic pain disorders. Several gene expression studies of DRG in preclinical pain models have been performed, but it is unclear if consistent gene changes are identifiable. We, therefore, compared several recent RNA-Seq data sets on the whole DRG in rodent models of nerve injury. Contrary to previous findings, we show hundreds of common differentially expressed genes and high positive correlation between studies, despite model and species differences. We also find, in contrast to previous studies, that 60% of the common rodent gene response aft...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

TRPV1 antagonist BCTC inhibits pH 6.0-induced pain in human skin
In conclusion, inhibiting TRPV1-mediated acidosis-induced pain could be a symptomatic and potentially also a disease-modifying approach. (Source: Pain)
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

An examination of the reciprocal and concurrent relations between behavioral and cardiac indicators of acute pain in toddlerhood
The aim of this study was to examine the concurrent and predictive relations between healthy toddlers' pain behavior and cardiac indicators (ie, heart rate [HR] and respiratory sinus arrhythmia [RSA]) during routine vaccinations. Caregiver–infant dyads were part of a longitudinal cohort observed during their 12- and 18-month vaccinations. Behavioral and cardiac data were simultaneously collected for 1-minute preneedle and 3-minutes postneedle. Videotapes were coded for pain behaviors (FLACC; Merkel et al., 1997), and cardiac data were analyzed (HR, RSA) during sequential 30-second epochs. Four separate cross-lagged p...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Pharmacological target-focused transcriptomic analysis of native vs cultured human and mouse dorsal root ganglia
Dorsal root ganglion (DRG) neurons detect sensory inputs and are crucial for pain processing. They are often studied in vitro as dissociated cell cultures with the assumption that this reasonably represents in vivo conditions. However, to the best of our knowledge, no study has directly compared genome-wide transcriptomes of DRG tissue in vivo versus in vitro or between laboratories and culturing protocols. Comparing RNA sequencing-based transcriptomes of native to cultured (4 days in vitro) human or mouse DRG, we found that the overall expression levels of many ion channels and G-protein–coupled receptors specifical...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Peripheral and central nervous system alterations in a rat model of inflammatory arthritis
In conclusion, we found evidence of anatomical, inflammatory, and neuronal alterations in the peripheral and central nervous systems in a model of IA. Together, these suggest that there may be a shift in the balance between incoming and outgoing excitation, and modulatory inhibitory tone in the DH. (Source: Pain)
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Alcohol-aggravated episodic pain in humans with SCN11A mutation and ALDH2 polymorphism
In this study, we collected and characterized one Chinese family with episodic pain. The SCN11A mutation (c.664C>A/p.Arg222Ser) was identified and cosegregated with the episodic pain phenotype. In addition, we found that alcohol intake triggered intense pain attacks and detected the ALDH2 polymorphism (c.1510G>A/p.Glu504Lys) in 3 patients with episodic pain. The alcohol-aggravated pain symptom and this ALDH2 polymorphism were also reconfirmed in our previously reported episodic pain patient with the Nav1.9 mutation (p.Ala808Gly, patient III-2 in HBBJ family). To assess the pathogenicity of the Nav1.9 mutation and the...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

A highly cognitive demanding working memory task may prevent the development of nociceptive hypersensitivity
Whether, how, and which cognitive factors modulate the development of secondary hypersensitivity/hyperalgesia after central sensitization is not fully understood. Here, we tested, in 3 subsequent experiments, whether being engaged in non–pain-related cognitive demanding tasks: (1) lessens the amount of hypersensitivity developed after an experimental procedure sensitizing nociceptive pathways; and (2) modulates cortical responses to somatosensory stimuli (measured by electroencephalography, EEG). In the first experiment, we validated a novel model in humans using low-frequency stimulation of the skin and demonstrated...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research

Differential impact of psychological and psychophysical stress on low back pain in mice
In this study, we first established and characterized a myofascial LBP model in mice based on nerve growth factor (NGF) injection into the low back muscles. Second, we investigated the effect of 2 different stress paradigms on this mouse LBP model by applying the chronic unpredictable stress and vertical chronic restraint stress (vCRS) paradigms, to mimic psychological and psychophysical stress, respectively. In these studies, we combined longitudinal behavioral tests with gene and protein expression analysis in the muscle, dorsal root ganglia, and spinal cord. Nerve growth factor-induced LBP was characterized by long-last...
Source: Pain - June 26, 2020 Category: Anesthesiology Tags: Research Paper Source Type: research