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Aberrant functional connectivity between anterior cingulate cortex and left insula in association with therapeutic response to biologics in inflammatory arthritis.

Brain activity is reported to be associated with individual pain susceptibility and inflammatory status, possibly contributing to disease activity assessment in inflammatory arthritis (IA) including rheumatoid arthritis (RA) and spondyloarthritis (SpA). However, what alteration of brain function associated with disease activity and therapeutic effectiveness in IA remains unclear. We aimed to identify the alterations of brain functional connectivity (FC) shared in both RA and SpA, and evaluate its relationship to anti-rheumatic treatment response using functional magnetic resonance imaging (MRI).

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Obstetricians’ prescribing practices for pain management after delivery.

To examine postpartum opioid prescribing practices. Obstetricians were interviewed about opioids: choice of opioid, clinical factors considered when prescribing, thoughts/beliefs about prescribing, and typical counseling provided. Inductive thematic analyses were used to identify themes. A total of 38 interviews were analyzed. Several key points emerged. The choice of opioid, dosing and number of pills prescribed varied widely. The mode of delivery is the primary consideration for prescribing opioids. All providers would prescribe opioids to breastfeeding women. Some providers offered counseling on nonopioid treatment of pain. At two large tertiary centers in Pennsylvania, the 38 physicians interviewed wrote 38 unique opioid prescriptions. Patient counseling addressed short-term pain management, but not the chronic overuse of opioids.

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Cranial autonomic symptoms in migraine are related to central sensitization: a prospective study of 164 migraine patients at a tertiary headache center.

Cranial autonomic symptoms (CASs) during migraine attacks are reported to be quite common regardless of ethnicity. In our previous study investigating 373 migraineurs, we found that 42.4% of them had CASs. The patients with CASs more frequently had cutaneous allodynia than did those without CASs, and we speculated that CASs were associated with central sensitization. The present study searched for substantial evidence on the relationship between CASs and central sensitization in migraine patients.

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Healthcare transition among young adults with childhood-onset chronic pain: A mixed methods study and proposed framework.

Chronic pain extends from childhood to adulthood for many young people. The transition from pediatric to adult care is a critical, yet understudied, healthcare task facing young adults with chronic pain. The aims of this observational, sequential mixed methods study were to (1) document the healthcare transition status of young adults with chronic pain (Stage 1, quantitative aim), (2) examine young adults' perspectives of barriers and facilitators of healthcare transition (Stage 2, qualitative aim), and (3) integrate findings to construct a theoretical framework of healthcare transition. A cohort was identified with childhood chronic pain and prior care in one of 15 multidisciplinary pediatric pain clinics across the United States and Canada. Approximately 6 years later, 189 young adults (M age = 21.0; age range = 18-24; 81.5% female) from this cohort with continuing chronic pain completed surveys for Stage 1, and a subsample (n = 17) completed qualitative interviews for Stage 2. Quantitative findings demonstrated that young adults may experience lapses in care, with 41.8% indicating they had not transitioned to adult pain services. Qualitative analysis revealed young adults experienced significant barriers (e.g., abrupt departure from pediatric care) as well as facilitators (e.g., acceptance of pain prognosis) of healthcare transition. Quantitative and qualitative findings were integrated to construct a healthcare transition framework for chronic pain, which highlights transition as a complex process involving multiple pathways, outcomes, and stakeholders. Advancements in research and practice are needed to develop transition services to bridge gaps in care and optimize health outcomes for young people with chronic pain. Perspective: This mixed-methods study demonstrated that 41.8% of young adults with chronic pain experience lapses in adult-centered pain care and identified key barriers and facilitators to successful healthcare transition. Findings were integrated to construct the first healthcare transition framework for youth with chronic pain.

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Metabolic reprogramming of synovial fibroblasts in osteoarthritis by inhibition of pathologically overexpressed pyruvate dehydrogenase kinases.

Osteoarthritis (OA) is the most common degenerative joint disease and a major cause of age-related disability worldwide, mainly due to pain, the disease's main symptom. Although OA was initially classified as a non-inflammatory joint disease, recent attention has been drawn to the importance of synovitis and fibroblast-like synoviocytes (FLS) in the pathogenesis of OA. FLS can be divided into two major populations: thymus cell antigen 1 (THY1)- FLS are currently classified as quiescent cells and assumed to destroy bone and cartilage, whereas THY1+ FLS are invasively proliferative cells that drive synovitis. Both THY1- and THY1+ FLS share many characteristics with fibroblast-like progenitors – mesenchymal stromal cells (MSC). However, it remains unclear whether synovitis-induced metabolic changes exist in FLS from OA patients and whether metabolic differences may provide a mechanistic basis for the identification of approaches to precisely convert the pathologically proliferative synovitis-driven FLS phenotype into a healthy one. To identify novel pathological mechanisms of the perpetuation and manifestation of OA, we analyzed metabolic, proteomic, and functional characteristics of THY1+ FLS from patients with OA. Proteome data and pathway analysis revealed that an elevated expression of pyruvate dehydrogenase kinase (PDK) 3 was characteristic of proliferative THY1+ FLS from patients with OA. These FLS also had the highest podoplanin (PDPN) expression and localized to the sublining but also the lining layer in OA synovium in contrast to the synovium of ligament trauma patients. Inhibition of PDKs reprogrammed metabolism from glycolysis towards oxidative phosphorylation and reduced FLS proliferation and inflammatory cytokine secretion. This study provides new mechanistic insights into the importance of FLS metabolism in the pathogenesis of OA. Given the selective overexpression of PDK3 in OA synovium and its restricted distribution in synovial tissue from ligament trauma patients and MSC, PDKs may represent attractive selective metabolic targets for OA treatment. Moreover, targeting PDKs does not affect cells in a homeostatic, oxidative state. Our data provide an evidence-based rationale for the idea that inhibition of PDKs could restore the healthy THY1+ FLS phenotype. This approach may mitigate the progression of OA and thereby fundamentally change the clinical management of OA from the treatment of symptoms to addressing causes.

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Electrophysiological alterations driving pain-associated spontaneous activity in human sensory neuron somata parallel alterations described in spontaneously active rodent nociceptors.

Neuropathic pain in rodents can be driven by ectopic spontaneous activity (SA) generated by sensory neurons in dorsal root ganglia (DRG). The recent demonstration that SA in dissociated human DRG neurons is associated with reported neuropathic pain in patients enables detailed comparison of pain-linked electrophysiological alterations driving SA in human DRG neurons to alterations that distinguish SA in nociceptors from SA in low-threshold mechanoreceptors (LTMRs) in rodent neuropathy models. Analysis of recordings from dissociated somata of patient-derived DRG neurons showed that SA and corresponding pain in both sexes were significantly associated with the three functional electrophysiological alterations sufficient to generate SA in the absence of extrinsic depolarizing inputs. These include enhancement of depolarizing spontaneous fluctuations of membrane potential (DSFs), which were analyzed quantitatively for the first time in human DRG neurons. The functional alterations were indistinguishable from SA-driving alterations reported for nociceptors in rodent chronic pain models. Irregular, low-frequency DSFs in human DRG neurons closely resemble DSFs described in rodent nociceptors while differing substantially from the high-frequency sinusoidal oscillations described in rodent LTMRs. These findings suggest that conserved physiological mechanisms of SA in human nociceptor somata can drive neuropathic pain despite documented cellular differences between human and rodent DRG neurons. Perspective: Electrophysiological alterations in human sensory neurons associated with patient-reported neuropathic pain include all three of the functional alterations that logically can promote spontaneous activity. The similarity of distinctively altered spontaneous depolarizations in human DRG neurons and rodent nociceptors suggests that spontaneously active human nociceptors can persistently promote neuropathic pain in patients.

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Unpleasant olfactory and gustatory stimuli increase pain unpleasantness in patients with chronic oral burning pain: an exploratory study.

Despite mounting evidence for the powerful influence of smell and taste substances in experimental pain, our knowledge of their effects in the clinical context is scarce, especially for patients with chronic oral burning pain. To fill this gap, we investigated the effect of olfactory and gustatory stimuli on pain perception in patients with chronic oral burning pain, a disabling condition that is difficult to manage and treat.

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Exploring the disparity between inflammation and disability in the 10-year outcomes of people with rheumatoid arthritis.

To identify groups of people with rheumatoid arthritis (RA) with different disability trajectories over ten years, despite comparable levels of inflammation.

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Investigating Characteristics of Idiopathic Inflammatory Myopathy Flares Using Daily Symptom Data Collected Via a Smartphone App.

To use daily data collected via a smartphone app for characterisation of patient-reported and "symptom-based" (using an a priori definition) flares in an adult idiopathic inflammatory myopathy (IIM) cohort.

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Pain tolerance in patients chronic pain is more strongly associated with physical activity than with anxiety and depression.

To explore the associations between habitual self-reported physical activity, pain sensitivity and patient-reported outcomes (including pain intensity) in patients with chronic pain.  Design: Cross-sectional, experimental study.  Subjects: Patients (n = 78), age range 18-65 years, with different chronic pain conditions (> 3 months) were compared with age- and gender-matched healthy controls (n = 98).  Methods: Multivariate correlations between self-reported physical activity, pressure pain thresholds, and patient-reported outcome measures were assessed.  Results: Lower perceived health status (p < 0.001, Cohen's d = 2.34), higher levels of depression (p < 0.001, Cohen's d = 1.77), and lower pressure pain tolerance threshold (p < 0.001, Cohen's d = 1.66) were the most prominent variables discriminating patients from controls. In patients, bivariate and multivariate analyses showed that higher pressure pain tolerance was associated with male gender, lower pain intensity and fewer painful regions, higher self-efficacy and more self-reported physical activity, but not with lower levels of anxiety and depression.  Conclusion: Pressure pain tolerance thresholds, as well as degree of depression and perceived health status discriminated between patients and controls, and there was an association between pain tolerance and level of self-reported physical activity in patients. This study highlights the importance of further research into how increased physical activity may improve pain sensitivity in patients with chronic pain.

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