Nociceptive and Transcriptomic Responses in a Swine Diabetic Wound Model Treated With a Topical Angiotensin 1 Receptor Antagonist.

BACKGROUND: Painful, treatment-resistant wounds are prevalent among diabetic patients and significantly affect health-related quality of life (HRQOL). Topical treatments may help alleviate pain without risk of dependence or side effects. However, there is a lack of topical wound compounds targeting pain-specific receptors. One possible target is proinflammatory angiotensin 1 receptor (AT1R), which is upregulated in diabetic skin and has been implicated in nociception. OBJECTIVES: We investigated the effects of topical valsartan, an AT1R antagonist, on pain (nociceptive thresholds) and gene expression changes (transcriptomics) in a swine model of diabetic wounds. METHODS: Eight wounds were surgically induced in diabetic, hyperglycemic Yucatan miniature swine ( n = 4). Topical AT1R antagonist was applied to wounds on one side and vehicle on the other side. Nocifensive testing was conducted at baseline and then weekly, beginning 7 days after wound induction. Mechanical and thermal stimuli were applied to the wound margins until a nocifensive reaction was elicited or a predetermined cutoff was reached. After 7 weeks of testing, tissue from the dorsal horn, dorsal root ganglion, and wounds were sequenced and analyzed with DESeq2. Unbiased pathway analyses using Metascape were conducted on differentially expressed genes. RESULTS: There was no significant difference in mechanical tolerance threshold between AT1R antagonist-treated and vehicle-treated wounds ( p = .106). Thermal tolerance was significantly higher in AT1R antagonist-treated wounds compared to vehicle-treated ( p = .015). Analysis of differentially expressed genes revealed enriched pathways of interest: interleukin-18 signaling in dorsal horn laminae IV-V and sensory perception of mechanical stimulus in wound tissue. DISCUSSION: In this study, wounds modeling diabetic ulcers were created in hyperglycemic swine and treated with a topical AT1R antagonist. AT1R-antagonist-treated wounds had a higher tolerance threshold than vehicle-treated wounds for thermal hyperalgesia, but not mechanical allodynia. Pathway analyses of differentially expressed genes revealed several pathways of interest for future pain research. Although further studies are needed to confirm the findings, this study can improve nursing care by providing information about a potential future treatment that may be used to decrease pain and improve HRQOL in patients with diabetic wounds.

Differential Gene Expression in Pain-Related Genes are not Affected by the Presence of Dementia.

BACKGROUND: Prior work has demonstrated differences in the transcriptome between those with and without chronic musculoskeletal pain. AIMS: The aim of this study was to explore whether pain-related gene expression is similar between individuals with and without dementia. DESIGN: This was a descriptive study using a one-time assessment. SETTINGS: PARTICIPANTS/SUBJECTS: A total of 20 older adults living in a continuing care retirement community, 50% of whom had dementia were inlcuded in this study. All were female and the mean age of participants was 89 (SD = 6). METHODS: Pain was evaluated based on the PROMIS Pain Intensity Short Form 3a. Whole blood was collected by venipuncture into Tempus vacutainer tubes (3 ml) and the RNA was extracted at the Translational Genomics Laboratory at the University of Maryland Baltimore. Analyses included a differential expression analysis, a weighted gene co-expression network analysis, and a pathway enrichment analysis. RESULTS: Eighty-three genes were differentially expressed between individuals with and without pain (p <.05). After normalizing gene counts and removing the low expressed genes, 18,028 genes were left in the final analysis. There was no clustering of the samples related to study variables of pain or dementia. CONCLUSION: The findings from this study provided some preliminary support that pain-related gene expression is similar between individuals with and without dementia.

Neurophysiological and transcriptomic predictors of chronic low back pain: Study protocol for a longitudinal inception cohort study.

Chronic low back pain is one of the most common, costly, and debilitating pain conditions worldwide. Increased mechanistic understanding of the transition from acute to chronic low back and identification of predictive biomarkers could enhance the clinical assessment performed by healthcare providers and enable the development of targeted treatment to prevent and/or better manage chronic low back pain. This study protocol was designed to identify the neurological and transcriptomic biomarkers predictive of chronic low back pain at low back pain onset. This is a prospective descriptive longitudinal inception cohort study that will follow 340 individuals with acute low back pain and 40 healthy controls over 2 years. To analyze the neurophysiological and transcriptomic biomarkers of low back pain, the protocol includes psychological and pain-related survey data that will be collected beginning within 6 weeks of low back pain onset (baseline, 6, 12, 24, 52 weeks, and 2 years) and remotely at five additional time points (8, 10, 16, 20 weeks, and 18 months). Quantitative sensory testing and collection of blood samples for RNA sequencing will occur during the six in-person visits. The study results will describe variations in the neurophysiological and transcriptomic profiles of healthy pain-free controls and individuals with low back pain who either recover to pain-free status or develop chronic low back pain.

Transition From Acute to Chronic Pain in Lower Extremity Fracture Patients: A Pain Phenotyping Protocol.

BACKGROUND: Traumatic injury is a major source of chronic pain, particularly for individuals with traumatic fracture of the fibula and/or tibia (lower extremity fracture [LEFx]). Although several factors (e.g., older age, being female, high pain intensity at time of initial injury) have been identified as risk factors for chronic pain associated with LEFx. Comprehensive biopsychosical models to predict the odds of transitioning from acute to chronic pain after LEFx are needed to better understand the underlying processes, predict risk for chronic pain, and develop personalized therapies for individuals at higher risk for developing chronic pain. OBJECTIVE: The aim of the study was to outline the study design that will be used to examine the physiological, psychological, and genetic/genomic variables-models that predict the transition from acute to chronic pain after LEFx. METHOD: This prospective descriptive cohort study will enroll 240 participants with a fibula and/or tibia fracture and 40 controls with no LEFx. Data will be collected during an in-hospital baseline visit, five in-person clinic visits (6 weeks, 12 weeks, 24 weeks, 52 weeks, and 24 months), and seven online between-visit surveys (2 weeks, 4 weeks, 8 weeks, 10 weeks, 16 weeks, 20 weeks, and 18 months) from participants with LEFx and at concordant intervals from controls. Measures will consist of 19 questionnaires characterizing pain and psychological status, neurophysiological testing for peripheral sensory nerve function, and peripheral blood samples collections for RNA sequencing. Illumina standard protocols will be used to sequence RNA, and read counts will be used to measure gene expression. ANALYSIS: Direct-entry, multiple logistic regression will be used to produce odds ratios expressing the relative risk on each explanatory variable when controlling for other predictors/covariates in the model. CONCLUSION: This study is one of the first to longitudinally characterize the biopsychosocial variables associated with a clinically relevant problem of the transition from acute to chronic posttraumatic fracture pain in individuals with LEFx. Results from this study will be used to construct predictive risk models of physiological, psychological, and genetic/genomic variables associated with increased risk for transitioning from acute to chronic pain status after LEFx. This work will lead to a better understanding of the trajectory of pain and relevant variables over time; initiate a better understanding of variables associated with risk for transitioning from acute to chronic pain; and, in the future, could provide a foundation for the identification of novel therapeutic targets to improve the outcomes of individuals with LEFx.

Global Transcriptomic Profile of Dorsal Root Ganglion and Physiological Correlates of Cisplatin-Induced Peripheral Neuropathy.

BACKGROUND: Multiple cell signaling pathways are implicated in the development, progression, and persistence of cisplatin-induced peripheral neuropathy. Although advances have been made in terms of understanding specific neurotoxic mechanisms, there are few predictive factors identified that can help inform the clinician approach to symptom prevention or management. OBJECTIVE: We investigate the differential sensitivity to cisplatin-induced peripheral neuropathy and examine the contribution of dorsal root ganglion (DRG) transcriptional profiles across two inbred strains of mice. METHODS: Cisplatin (4 mg/kg intraperitoneal or vehicle control) was administered twice a week for 4 weeks to adult female C57BL/6J and A/J mice-the C57BL/6J strain of mice characterized by a robust mechanical allodynia and the A/J with a mild largely resistant allodynia phenotype. Peripheral nerve conduction velocities (NCVs), electrophysiological evaluation of wide dynamic range (WDR) neurons, morphological examination of DRG neurons, and microarray analysis of spinal cord tissues were compared across the 4 weeks. RESULTS: The A/J strain presents with an early, mild nocifensive response to cisplatin with reduced neuronal activity in WDR neurons and small changes in cross-sectional nucleus size in DRG neurons at 4 weeks. The more nocifensive-sensitive C57BL/6J strain presents with no early changes in WDR neuron responsiveness; however, there were significant changes in DRG size. Both strains demonstrate a drop in NCV after 4 weeks of treatment, with the greatest reduction present in the A/J strain. Transcriptome data implicate neuroimmune modulation in the differential response to cisplatin in the DRGs of A/J and C57BL/6J mice. DISCUSSION: Nocifensive responses in both strains implicate involvement of small myelinated and unmyelinated fibers in neurotoxic cisplatin response, whereas reductions in NCV reflect involvement of the largest myelinated fibers in the peripheral nerves. Microarray data analysis identifies neuropathy-relevant gene sets with differential activation of pathways, suggesting a role for antigen presentation in the differential neurotoxic response to cisplatin across strains. Further research is indicated to determine the relative contributions of each of these potential pathological mechanisms to both the neurotoxic response to cisplatin and to the potential for targeted therapy.

Change in Pain Score after Administration of Analgesics for Lower Extremity Fracture Pain during Hospitalization.

BACKGROUND: Effective acute pain management following injury is critical to improve short-and long-term patient outcomes. Analgesics can effectively reduce pain intensity, yet half of injury patients report moderate to severe pain during hospitalization. PURPOSE: The primary aim of this study was to identify the analgesic, different analgesic combinations, or analgesic and adjuvant analgesic combination that generated the largest percent change from pre- to post-analgesic pain score. DESIGN: This was a descriptive retrospective cohort study of 129 adults admitted with lower extremity fractures to a trauma center. METHODS: Name, dose, and frequency of analgesics and adjuvant analgesics administered from admission to discharge were collected from medical records. Percent change was calculated from pain scores documented on the 0-10 numeric rating scale. RESULTS: The analgesic with largest percent change from pre- to post-administration pain score was hydromorphone 2 mg IV (53%) for the emergency department and morphine 4 mg IV (54%) for the in-patient unit. All analgesics administered in the emergency department and ∼50% administered on the in-patient unit produced a minimal (15%) decrease in pain score. CONCLUSIONS: This study revealed that few analgesics administered in the emergency department and the in-patient unit to patients with lower extremity fractures provide adequate pain relief. In the emergency department, all analgesics administered resulted in at least minimal improvement of pain. On the in-patient unit 13 analgesic doses resulted at least minimal improvement in pain while nine doses did not even reach 20% change in pain. Findings from this study can be used guide the treatment of fracture pain in the hospital.

Precision health: Advancing symptom and self-management science.

BACKGROUND: Precision health considers individual lifestyle, genetics, behaviors, and environment context and facilitates interventions aimed at helping individuals achieve well-being and optimal health. PURPOSE: To present the Nursing Science Precision Health (NSPH) Model and describe the integration of precision health concepts within the domains of symptom and self-management science as reflected in the National Institute of Nursing Research P30 Centers of Excellence and P20 Exploratory Centers. METHODS: Center members developed the NSPH Model and the manuscript based on presentations and discussions at the annual NINR Center Directors Meeting and in follow-up telephone meetings. DISCUSSION: The NSPH Model comprises four precision components (measurement; characterization of phenotype including lifestyle and environment; characterization of genotype and other biomarkers; and intervention target discovery, design, and delivery) that are underpinned by an information and data science infrastructure. CONCLUSION: Nurse scientist leadership is necessary to realize the vision of precision health as reflected in the NSPH Model.

Truncated TrkB.T1-Mediated Astrocyte Dysfunction Contributes to Impaired Motor Function and Neuropathic Pain after Spinal Cord Injury.

Following spinal cord injury (SCI), astrocytes demonstrate long-lasting reactive changes, which are associated with the persistence of neuropathic pain and motor dysfunction. We previously demonstrated that upregulation of trkB.T1, a truncated isoform of the brain-derived neurotrophic factor receptor (BDNF), contributes to gliosis after SCI, but little is known about the effects of trkB.T1 on the function of astrocytes. As trkB.T1 is the sole isoform of trkB receptors expressed on astrocytes, we examined the function of trkB.T1-driven astrocytes in vitro and in vivo Immunohistochemistry showed that trkB.T1+ cells were significantly upregulated 7 d after injury, with sustained elevation in white matter through 8 weeks. The latter increase was predominantly found in astrocytes. TrkB.T1 was also highly expressed by neurons and microglia/macrophages at 7 d after injury and declined by 8 weeks. RNA sequencing of cultured astrocytes derived from trkB.T1+/+ (WT) and trkB.T1-/- (KO) mice revealed downregulation of migration and proliferation pathways in KO astrocytes. KO astrocytes also exhibited slower migration/proliferation in vitro in response to FBS or BDNF compared with WT astrocytes. Reduced proliferation of astrocytes was also confirmed after SCI in astrocyte-specific trkB.T1 KO mice; using mechanical allodynia and pain-related measurements on the CatWalk, these animals also showed reduced hyperpathic responses, along with improved motor coordination. Together, our data indicate that trkB.T1 in astrocytes contributes to neuropathic pain and neurological dysfunction following SCI, suggesting that trkB.T1 may provide a novel therapeutic target for SCI.SIGNIFICANCE STATEMENT Neuropathic pain after spinal cord injury (SCI) may in part be caused by upregulation of the brain-derived neurotrophic factor (BDNF) receptor trkB.T1, a truncated isoform of BDNF. TrkB.T1 is the only isoform of tropomyosin-related receptor kinase type B (trkB) receptors expressed on astrocytes. Here, we showed that trkB.T1 is significantly increased in the injured mouse spinal cord, where it is predominantly found in astrocytes. RNA sequencing of cultured astrocytes demonstrated downregulation of migration and proliferation pathways in trkB.T1 KO astrocytes. This was validated in vivo, where deletion of trkB.T1 in astrocytes reduced cell proliferation and migration. After SCI, astrocyte-specific trkB.T1 KO mice showed reduced hyperpathic responses and improved motor coordination. Therefore, the trkB.T1 receptor plays a significant pathophysiological role after SCI, and may provide a novel therapeutic target for SCI.

Biomarkers as Common Data Elements for Symptom and Self-Management Science.

PURPOSE: Biomarkers as common data elements (CDEs) are important for the characterization of biobehavioral symptoms given that once a biologic moderator or mediator is identified, biologically based strategies can be investigated for treatment efforts. Just as a symptom inventory reflects a symptom experience, a biomarker is an indicator of the symptom, though not the symptom per se. The purposes of this position paper are to (a) identify a "minimum set" of biomarkers for consideration as CDEs in symptom and self-management science, specifically biochemical biomarkers; (b) evaluate the benefits and limitations of such a limited array of biomarkers with implications for symptom science; (c) propose a strategy for the collection of the endorsed minimum set of biologic samples to be employed as CDEs for symptom science; and (d) conceptualize this minimum set of biomarkers consistent with National Institute of Nursing Research (NINR) symptoms of fatigue, depression, cognition, pain, and sleep disturbance. DESIGN AND METHODS: From May 2016 through January 2017, a working group consisting of a subset of the Directors of the NINR Centers of Excellence funded by P20 or P30 mechanisms and NINR staff met bimonthly via telephone to develop this position paper suggesting the addition of biomarkers as CDEs. The full group of Directors reviewed drafts, provided critiques and suggestions, recommended the minimum set of biomarkers, and approved the completed document. Best practices for selecting, identifying, and using biological CDEs as well as challenges to the use of biological CDEs for symptom and self-management science are described. Current platforms for sample outcome sharing are presented. Finally, biological CDEs for symptom and self-management science are proposed along with implications for future research and use of CDEs in these areas. FINDINGS: The recommended minimum set of biomarker CDEs include pro- and anti-inflammatory cytokines, a hypothalamic-pituitary-adrenal axis marker, cortisol, the neuropeptide brain-derived neurotrophic factor, and DNA polymorphisms. CONCLUSIONS: It is anticipated that this minimum set of biomarker CDEs will be refined as knowledge regarding biologic mechanisms underlying symptom and self-management science further develop. The incorporation of biological CDEs may provide insights into mechanisms of symptoms, effectiveness of proposed interventions, and applicability of chosen theoretical frameworks. Similarly, as for the previously suggested NINR CDEs for behavioral symptoms and self-management of chronic conditions, biological CDEs offer the potential for collaborative efforts that will strengthen symptom and self-management science. CLINICAL RELEVANCE: The use of biomarker CDEs in biobehavioral symptoms research will facilitate the reproducibility and generalizability of research findings and benefit symptom and self-management science.

Acute Pain Characteristics in Patients with and without Chronic Pain following Lower Extremity Injury.

Many patients with injuries to lower extremities report chronic pain. High pain intensity at time of admission for injury is a risk factor for chronic pain, but it is not clear whether specific acute pain patterns following injury influence the development of chronic pain. To examine the relationship between the pain trajectory, the mean pain score, and the frequency of pain documentation during the immediate hospitalization following injury, with the report of chronic pain. This was a descriptive, retrospective cohort study of adults admitted with lower extremity fractures to an academic urban trauma center. Participants, 6-45 months postinjury, rated their current pain, worst pain, and average pain over the last 3 months. Pain scores from hospitalization associated with the injury were obtained through a retrospective chart review. The pain trajectory, mean pain score, and frequency of pain documentation was compared between patients with and without chronic pain. A total of 129 patients were enrolled in this study and 78% reported chronic pain at the site of injury. The mean pain score (5.1 vs. 4.2) and first pain score (5.6 vs. 3.4) were higher for patients with chronic pain compared to patients with no chronic pain. Consistent with other studies, high pain intensity at time of injury was associated with chronic pain. The findings contribute valuable information about acute pain characteristics associated with chronic pain and provide insight into the importance of early and adequate acute pain treatment.

Characteristics of Patients with Lower Extremity Trauma with Improved and Not Improved Pain During Hospitalization: A Pilot Study.

Up to 62% of patients report chronic pain at the injury site 6-12 months after blunt trauma, with pain from lower extremity fractures exceeding that from other sites. High pain intensity at time of injury is a risk factor for chronic pain, but it is not clear what patient characteristics influence the pain intensity level during the immediate hospitalization following injury. The purpose of this pilot study was to determine the feasibility of collecting pain scores from medical records to calculate pain trajectories and to determine whether it is possible to examine patient characteristics by classifying them into those whose pain improved and those whose pain did not improve. This descriptive study retrospectively reviewed medical records of 18 randomly chosen patients admitted to an academic trauma center. Patient characteristics and pain scores were collected form electronic and handwritten medical records. The pain trajectories calculated from routinely collected pain scores during the inpatient stay showed that for 44% of patients the pain improved during the hospitalization, for 39% the pain remained the same, and for 17% the pain worsened. The variables age, smoking, weight, abbreviated injury scores, length of hospital stay, mean pain score, and opioid equianalgesic dose differed based on pain trajectory. While patient characteristics differed based on pain trajectory, any significant effects seen from individual tests should be considered tentative, given the number of analyses conducted on this data set. However, feasibility and significance of conducting a larger study has been established.

The Impact of Pain Management with Opioids among Older Adults Post Orthopedic Trauma.

Pain has a significant effect on physical and psychological outcomes for older adults post orthopedic trauma. The purpose of this study was to describe the management of pain among older trauma patients and consider differences between those who received 3 or more dosages daily of opioids versus those who did not. This was a secondary data analysis using data from an intervention study testing the effect of Function Focused Care among older orthopedic trauma patients (FFC-AC). The FFC-AC study was done on trauma units in two acute care settings designated as Level I or II trauma centers from September 2014 to September 2015. All participants from the parent FFC-AC study were included. Data collection for the parent study was done within 24 hours of admission and within 24 hours of discharge and included demographics, medications, assessment of function, physical activity, mood, physical resilience, and whether the patient had pain and their pain intensity. Patient records included all 89 individuals from the parent study, 59 (66%) of whom were female and 82 (92%) were white. Records indicated that those who received more than three dosages per day of opioids had a shorter length of stay, were younger, had more intense pain, and were more resilient compared with those who received less than three dosages per day. This secondary data analysis provides support for the importance of considering pain and pain management among older adults post trauma.

Evaluation of dynamic weight bearing for measuring nonevoked inflammatory hyperalgesia in mice.

BACKGROUND: Animal models in pain research have suggested that inclusion of both evoked and nonevoked behavioral measures is needed to better reflect the human pain experience. Individuals with chronic pain are known to experience spontaneous pain, in addition to pain after exposure to an external stimulus. Recently, the dynamic weight bearing (DWB) apparatus was developed to assess for nonevoked hyperalgesia by capturing weight bearing and surface distribution in the paws of mice after acute inflammation. OBJECTIVES: The aim of this study was to evaluate the DWB test as a measure of nonevoked hyperalgesia. METHODS: The experimental group received an intraplantar injection in the left hind paw of the inflammatory agent--complete Freund's adjuvant (CFA)--whereas the vehicle control group received a saline injection and the naive control group had no treatment. Calipers and a plethysmometer were used to verify inflammation and the hot-plate test was used as a measure for stimulus-evoked hyperalgesia. Data were collected at baseline; 3 hours; and 1, 3, and 7 days after injection. RESULTS: Mice injected with CFA showed a statistically significant higher mean paw thickness and volume displacement compared with the vehicle and naive control groups. In the hot-plate testing, CFA-treated mice showed lower response temperature at 7 days compared with the other groups. On the DWB test, CFA-treated mice showed a reduction in the ipsilateral paw load and surface area compared with the contralateral paw load at Days 1, 3, and 7. DISCUSSION: Mice with inflammation showed alterations in weight bearing as well as increased thermal hyperalgesia in comparison with control groups. These findings support the use of the DWB test as a tool for measuring nonevoked inflammatory hyperalgesia in a mouse model.

TrkB.T1 contributes to neuropathic pain after spinal cord injury through regulation of cell cycle pathways.

Spinal cord injury (SCI) frequently causes severe, persistent central neuropathic pain that responds poorly to conventional pain treatments. Brain-derived neurotrophic factor (BDNF) signaling appears to contribute to central sensitization and nocifensive behaviors in certain animal models of chronic pain through effects mediated in part by the alternatively spliced truncated isoform of the BDNF receptor tropomyosin-related kinase B.T1 (trkB.T1). Mechanisms linking trkB.T1 to SCI-induced chronic central pain are unknown. Here, we examined the role of trkB.T1 in central neuropathic pain after spinal cord contusion. Genetic deletion of trkB.T1 in mice significantly reduced post-SCI mechanical hyperesthesia, locomotor dysfunction, lesion volumes, and white matter loss. Whole genome analysis, confirmed at the protein level, revealed that cell cycle genes were upregulated in trkB.T1(+/+) but not trkB.T1(-/-) spinal cord after SCI. TGFß-induced reactive astrocytes from WT mice showed increased cell cycle protein expression that was significantly reduced in astrocytes from trkB.T1(-/-) mice that express neither full-length trkB nor trkB.T1. Administration of CR8, which selectively inhibits cyclin-dependent kinases, reduced hyperesthesia, locomotor deficits, and dorsal horn (SDH) glial changes after SCI, similar to trkB.T1 deletion, without altering trkB.T1 protein expression. In trkB.T1(-/-) mice, CR8 had no effect. These data indicate that trkB.T1 contributes to the pathobiology of SCI and SCI pain through modulation of cell cycle pathways and suggest new therapeutic targets.

Correspondence between neurophysiological and clinical measurements of chemotherapy-induced peripheral neuropathy: secondary analysis of data from the CI-PeriNomS study.

Chemotherapy-induced peripheral neuropathy (CIPN) lacks standardized clinical measurement. The objective of the current secondary analysis was to examine data from the CIPN Outcomes Standardization (CI-PeriNomS) study for associations between clinical examinations and neurophysiological abnormalities. Logistic regression estimated the strength of associations of vibration, pin, and monofilament examinations with lower limb sensory and motor amplitudes. Examinations were classified as normal (0), moderately abnormal (1), or severely abnormal (2). Among 218 participants, those with class 1 upper extremity (UE) and classes 1 or 2 lower extremity (LE) monofilament abnormality were 2.79 (95% confidence interval [CI]: 1.28-6.07), 3.49 (95%CI: 1.61-7.55), and 4.42 (95%CI: 1.35-14.46) times more likely to have abnormal sural nerve amplitudes, respectively, compared to individuals with normal examinations. Likewise, those with class 2 UE and classes 1 or 2 LE vibration abnormality were 8.65 (95%CI: 1.81-41.42), 2.54 (95%CI: 1.19-5.41), and 7.47 (95%CI: 2.49-22.40) times more likely to have abnormal sural nerve amplitudes, respectively, compared to participants with normal examinations. Abnormalities in vibration and monofilament examinations are associated with abnormal sural nerve amplitudes and are useful in identifying CIPN.

Evaluation of chemotherapy-induced peripheral neuropathy using current perception threshold and clinical evaluations.

PURPOSE: Chemotherapy-induced peripheral neuropathy (CIPN) is increasing with introduction of new and combination cancer pharmacotherapies. This study evaluated associations between clinical and self-report measurements and current perception threshold (CPT), a neuroselective measure of sensory nerve function that may detect asymptomatic CIPN damage. METHODS: Data for this secondary analysis were from a prospective, observational study using CPT to evaluate CIPN. Bivariate mixed models, accounting for the intraclass correlation between repeated patient assessments, were used to assess the relationship between CPT at each frequency (5, 250, and 2,000 Hz) and each subjective measure (Neuropathic Pain Scale, FACT-GOGntx) and objective measurement (quantitative sensory testing, deep tendon reflexes, and grip strength). RESULTS: A total of 29 chemotherapy-naïve subjects with various cancer types had a mean age of 56.7 (SD 10.4); nine subjects developed CIPN grade >1 using NCI CTC-AE criteria. Cold detection thresholds were inversely associated with CPT 5 [b(95 % CI) = -2.5(-4.5, -0.5)] and CPT 2,000 [-7.5(-11.8, -3.3)] frequencies. FACT GOG-ntx quality of life (QoL) scale and neurotoxicity and function subscales were inversely associated with CPT 2,000 [-1.8 (-3.5, -0.05), -2.2 (-4.2, -0.2), and -5.4 (-9.8, -0.9), respectively], indicating worsening QoL, impairment, and function as hypoesthesia increases. CONCLUSIONS: CPT 2,000 may identify impending worsening of patient-reported outcomes such as QoL.

Dissecting Genetic Mechanisms of Differential Locomotion, Depression, and Allodynia after Spinal Cord Injury in Three Mouse Strains.

Strain differences have been reported for motor behaviors, and only a subset of spinal cord injury (SCI) patients develop neuropathic pain, implicating genetic or genomic contribution to this condition. Here, we evaluated neuropsychiatric behaviors in A/J, BALB/c, and C57BL/6 male mice and tested genetic or genomic alterations following SCI. A/J and BALB/c naive mice showed significantly less locomotor activity and greater anxiety-like behavior than C57BL/6 mice. Although SCI elicited locomotor dysfunction, C57BL/6 and A/J mice showed the best and the worst post-traumatic recovery, respectively. Mild (m)-SCI mice showed deficits in gait dynamics. All moderate/severe SCI mice exhibited similar degrees of anxiety/depression. mSCI in BALB/c and A/J mice resulted in depression, whereas C57BL/6 mice did not exhibit depression. mSCI mice had significantly lower mechanical thresholds than their controls, indicating high cutaneous hypersensitivity. C57BL/6, but not A/J and BLAB/c mice, showed significantly lower heat thresholds than their controls. C57BL/6 mice exhibited spontaneous pain. RNAseq showed that genes in immune responses and wound healing were upregulated, although A/J mice showed the largest increase. The cell cycle and the truncated isoform of trkB genes were robustly elevated in SCI mice. Thus, different genomics are associated with post-traumatic recovery, underscoring the likely importance of genetic factors in SCI.

Feasibility and Acceptability of an Online Yoga Study Among Individuals with Irritable Bowel Syndrome (IBS).

Irritable bowel syndrome (IBS) is a gastrointestinal disorder characterized by chronic abdominal pain that is often comorbid with psychiatric disorders and other pain-related conditions. The practice of yoga improves symptoms among patients with IBS, although the virtual delivery of yoga in this patient population remains understudied. The purpose of this article is to report feasibility and acceptability of a 6-week pilot yoga intervention among IBS and healthy control participants, which was transitioned to an online format in response to the COVID-19 pandemic. Participants attended 3 virtual study visits and received 60-minute private yoga sessions twice weekly for 6 weeks via Zoom. Sixteen females (n = 8 in IBS group, n = 8 in control group) with a mean age of 34.7 identified as White (87.5%) and Asian (12.5%). All participants attended all 3 study visits; 14 participants attended 12 yoga sessions, 1 attended 11, and 1 attended 9. At the end of the study, 81.3% of participants strongly agreed that participating in the online study was beneficial and convenient, and 87.5% strongly agreed that participating in the online yoga program was beneficial. Our online study and yoga intervention was feasible and acceptable; future studies with larger and more diverse populations will be conducted to investigate health effects among individuals with IBS.

Dietary Composition, Meal Timing, and Cancer-Related Fatigue: Insights From the Women's Healthy Eating and Living Study.

BACKGROUND: Cancer-related fatigue is difficult to treat, and dietary interventions are promising yet underused. OBJECTIVE: We explored associations between dietary patterns and fatigue, and the effect of a dietary intervention versus control on fatigue using Women's Healthy Eating and Living study data, plus mediators and moderators of the intervention effect. METHODS: The Women's Healthy Eating and Living study was a randomized controlled trial among early-stage breast cancer survivors. The 4-year intervention encouraged fruits, vegetables, fiber, and 15% to 20% calories from fat. Fatigue outcomes included a 9-item energy scale and a single-item tiredness question. Dietary quality was estimated using a modified Healthy Eating Index (24-hour dietary recall) and serum carotenoid concentrations. Nutrient timing was obtained from 4-day food logs. RESULTS: Among 2914 total participants, lower body mass index was associated with less tiredness and more energy at baseline (P < .001 for both). Earlier start and end times for daily eating windows were associated with less tiredness (P = .014 and P = .027, respectively) and greater energy (P = .006 and P = .102, respectively). The intervention did not lead to improvements in fatigue on average (P > .125). However, the intervention was more effective for participants who were younger, had fewer comorbidities, and did not have radiation treatment. Mediators included increases in serum carotenoids, increases in the modified Healthy Eating Index, and weight loss/maintenance. CONCLUSION: Diet quality and earlier eating windows were associated with less fatigue. IMPLICATIONS FOR PRACTICE: Programs that encourage high diet quality and a morning meal and discourage nighttime eating should be tested for efficacy in reducing cancer-related fatigue in survivorship.