61 research outputs found
IFN-γ receptor and STAT1 signaling in B cells are central to spontaneous germinal center formation and autoimmunity.
Spontaneously developed germinal centers (GCs [Spt-GCs]) harbor autoreactive B cells that generate somatically mutated and class-switched pathogenic autoantibodies (auto-Abs) to promote autoimmunity. However, the mechanisms that regulate Spt-GC development are not clear. In this study, we report that B cell-intrinsic IFN-γ receptor (IFN-γR) and STAT1 signaling are required for Spt-GC and follicular T helper cell (Tfh cell) development. We further demonstrate that IFN-γR and STAT1 signaling control Spt-GC and Tfh cell formation by driving T-bet expression and IFN-γ production by B cells. Global or B cell-specific IFN-γR deficiency in autoimmune B6.Sle1b mice leads to significantly reduced Spt-GC and Tfh cell responses, resulting in diminished antinuclear Ab reactivity and IgG2c and IgG2b auto-Ab titers compared with B6.Sle1b mice. Additionally, we observed that the proliferation and differentiation of DNA-reactive B cells into a GC B cell phenotype require B cell-intrinsic IFN-γR signaling, suggesting that IFN-γR signaling regulates GC B cell tolerance to nuclear self-antigens. The IFN-γR deficiency, however, does not affect GC, Tfh cell, or Ab responses against T cell-dependent foreign antigens, indicating that IFN-γR signaling regulates autoimmune, but not the foreign antigen-driven, GC and Tfh cell responses. Together, our data define a novel B cell-intrinsic IFN-γR signaling pathway specific to Spt-GC development and autoimmunity. This novel pathway can be targeted for future pharmacological intervention to treat systemic lupus erythematosus
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Western Diet-Fed, Aortic-Banded Ossabaw Swine: A Preclinical Model of Cardio-Metabolic Heart Failure.
The development of new treatments for heart failure lack animal models that encompass the increasingly heterogeneous disease profile of this patient population. This report provides evidence supporting the hypothesis that Western Diet-fed, aortic-banded Ossabaw swine display an integrated physiological, morphological, and genetic phenotype evocative of cardio-metabolic heart failure. This new preclinical animal model displays a distinctive constellation of findings that are conceivably useful to extending the understanding of how pre-existing cardio-metabolic syndrome can contribute to developing HF
Using emergency department-based inception cohorts to determine genetic characteristics associated with long term patient outcomes after motor vehicle collision: Methodology of the CRASH study
<p>Abstract</p> <p>Background</p> <p>Persistent musculoskeletal pain and psychological sequelae following minor motor vehicle collision (MVC) are common problems with a large economic cost. Prospective studies of pain following MVC have demonstrated that demographic characteristics, including female gender and low education level, and psychological characteristics, including high pre-collision anxiety, are independent predictors of persistent pain. These results have contributed to the psychological and social components of a biopsychosocial model of post-MVC pain pathogenesis, but the biological contributors to the model remain poorly defined. Recent experimental studies indicate that genetic variations in adrenergic system function influence the vulnerability to post-traumatic pain, but no studies have examined the contribution of genetic factors to existing predictive models of vulnerability to persistent pain.</p> <p>Methods/Design</p> <p>The Project CRASH study is a federally supported, multicenter, prospective study designed to determine whether variations in genes affecting synaptic catecholamine levels and alpha and beta adrenergic receptor function augment social and psychological factors in a predictive model of persistent musculoskeletal pain and posttraumatic stress disorder (PTSD) following minor MVC. The Project CRASH study will assess pain, pain interference and PTSD symptoms at 6 weeks, 6 months, and 1 year in approximately 1,000 patients enrolled from 8 Emergency Departments in four states with no-fault accident laws.</p> <p>Discussion</p> <p>The results from this study will provide insights into the pathophysiology of persistent pain and PTSD following MVC and may serve to improve the ability of clinicians and researchers to identify individuals at high risk for adverse outcomes following minor MVC.</p
Effect of pain location and duration on life function in the year after motor vehicle collision
Persistent musculoskeletal pain is common after motor vehicle collision (MVC) and often results in substantial disability. The objective of this study was to identify distributions of post-MVC pain which most interfere with specific life functions and which have the greatest interference with aggregate life function. Study data were obtained from a prospective longitudinal multicenter emergency department-based cohort of 948 European Americans experiencing MVC. Overall pain (0–10 numeric rating scale (NRS)), pain in each of 20 body regions (0–10 NRS), and pain interference (Brief Pain Inventory, 0–10 NRS) were assessed 6 weeks, 6 months, and 1 year after MVC. After adjustment for overall pain intensity, an axial distribution of pain caused the greatest interference with most specific life functions (R2 = 0.15–0.28, association p-values <.001) and with overall function. Axial pain explained more than twice as much variance in pain interference as other pain distributions. However, not all patients with axial pain had neck pain. Moderate or severe low back pain was as common as neck pain at week 6 (prevalence 37% for each) and overlapped with neck pain in only 23% of patients. Further, pain across all body regions accounted for nearly twice as much of the variance in pain interference as neck pain alone (60% vs. 34%). These findings suggest that studies of post-MVC pain should not focus on neck pain alone
Pain, distress, and anticipated recovery for older versus younger emergency department patients after motor vehicle collision
Abstract Background Motor vehicle collisions (MVCs) are the second most common injury mechanism resulting in emergency department (ED) visits by older adults. MVCs result in substantial pain and psychological distress among younger individuals, but little is known about the occurrence of these symptoms in older individuals. We describe the frequency of and characteristics associated with pain, distress, and anticipated time for physical and emotional recovery for older adults presenting to the ED after MVC in comparison to younger adults. Methods In-person interviews were conducted for adults presenting to one of eight EDs after MVC without an obvious fracture or injury requiring admission as part of two prospective studies. Pain severity was assessed using a 0–10 verbal scale. Distress was assessed using the Peritraumatic Distress Inventory (range 0–52). Patients were asked to estimate their expected time for physical and emotional recovery; these responses were dichotomized to <30 or ≥30 days. ED pain and distress and associations between patient and collision characteristics and ED pain and distress were examined for patients age 65 years and older and patients age 18 to 64. Results Older (n = 96) and younger (n = 943) adults had the same mean pain scores (5.5, SD 2.5 vs. 5.5, SD 2.4). Distress scores were lower in older than in younger adults (15.5, SD 9 vs. 19.2, SD 10). A higher percentage of older adults than younger adults had an anticipated time to physical recovery ≥30 days (41%, 95% confidence interval [CI] 28%-55% vs. 11%, 95% CI 9%-13%). Similarly, older adults were more likely to have an anticipated time for emotional recovery ≥30 days (45%, 95% CI 35%-55% vs. 17%, 95% CI 15%-20%). Older adults were less likely than younger adults to have moderate or severe neck pain (score ≥4) (25%, 95% CI 23% to 41% vs. 54%, 95% CI 48% to 60%) or back pain (31%, 95% CI 23% to 46% vs. 56%, 95% CI 51 to 62%) but more likely to have moderate or severe chest pain (42%, 95% CI 32% to 50% vs. 20%, 95% CI 16 to 23%). Pre-MVC depressive symptoms and pain catastrophizing were positively associated with pain and distress in both older and younger adults. Conclusions In our cohort, older adults who presented to the ED after MVC experienced similar pain severity as younger patients and less distress but were more likely to estimate their times for physical and emotional recovery to be 30 days or more. Increased emergency provider awareness of acute pain and distress symptoms among older patients experiencing MVC may improve outcomes for these patients
More educated emergency department patients are less likely to receive opioids for acute pain
Inadequate treatment of pain in United States emergency departments (EDs) is common, in part due to the limited and idiosyncratic use of opioids by emergency providers. We sought to determine the relationship between patient socioeconomic characteristics and the likelihood they would receive opioids during a pain-related ED visit. We conducted a cross-sectional analysis of ED data obtained as part of a multi-center study of outcomes after minor motor vehicle collision (MVC). Study patients were non-hispanic whites between the ages of 18–65 who were evaluated and discharged home from one of nine EDs in four states. Socioeconomic characteristics included educational attainment and income. Of 690 enrolled patients, the majority had moderate or severe pain (80%). Patients with higher education attainment had lower levels of pain, pain catastrophizing, perceived life-threat, and distress. More educated patients were also less likely to receive opioids during their ED visit. Opioids were given to 54% of patients who did not complete high school vs. 10% of patients with post-college education (chi-square test p<.001). Differences in the frequency of opioid administration between patients with the lowest educational attainment (39%, 95% CI 22%–60%)and highest educational attainment (13%, 95% CI 7%–23%) remained after adjustment for age, sex, income, and pain severity (p=.01). In this sample of post-MVCED patients, more educated patients were less likely to receive opioids. Further study is needed to assess the generalizability of these findings and determine the reason for the difference
Restricted activity and persistent pain following motor vehicle collision among older adults: a multicenter prospective cohort study
Abstract Background Restricted physical activity commonly occurs following acute musculoskeletal pain in older adults and may influence long-term outcomes. We sought to examine the relationship between restricted physical activity after motor vehicle collision (MVC) and the development of persistent pain. Methods We examined data from a prospective study of adults ≥65 years of age presenting to the emergency department (ED) after MVC without life-threatening injuries. Restricted physical activity 6 weeks after MVC was defined in three different ways: 1) by a ≥25 point decrease in Physical Activity Scale in the Elderly (PASE) score, 2) by the answer “yes” to the question, “during the past two weeks, have you stayed in bed for at least half a day?”, and 3) by the answer “yes” to the question, “during the past two weeks, have you cut down on your usual activities as compared to before the accident?” We examined relationships between each definition of restricted activity and pain severity, pain interference, and functional capacity at 6 months with adjustment for confounders. Results Within the study sample (N = 164), adjusted average pain severity scores at 6 months did not differ between patients with and without restricted physical activity based on decreased PASE score (2.54 vs. 2.07, p = 0.32). In contrast, clinically and statistically important differences in adjusted average pain severity at 6 months were observed for patients who reported spending half a day in bed vs. those who did not (3.56 vs. 1.91, p < 0.01). In adjusted analyses, both decreased PASE score and cutting down on activity were associated with functional capacity at 6 months, but only decreased PASE score was associated with increased ADL difficulty at 6 months (0.70 vs. -0.01, p = 0.02). Conclusions Among older adults experiencing MVC, those reporting bed rest or reduced activity 6 weeks after the collision reported higher pain and pain interference scores at 6 months. More research is needed to determine if interventions to promote activity can improve outcomes after MVC in older adults
Persistent Pain Among Older Adults Discharged Home From the Emergency Department After Motor Vehicle Crash: A Prospective Cohort Study
Motor vehicle collisions (MVCs) are the second most common form of trauma among older adults. We sought to describe the incidence, risk factors, and consequences of persistent pain among older adults evaluated in the emergency department (ED) after an MVC
Neighborhood Disadvantage and Neural Correlates of Threat and Reward Processing in Survivors of Recent Trauma
Importance Differences in neighborhood socioeconomic characteristics are important considerations in understanding differences in risk vs resilience in mental health. Neighborhood disadvantage is associated with alterations in the function and structure of threat neurocircuitry.
Objective To investigate associations of neighborhood disadvantage with white and gray matter and neural reactivity to positive and negative stimuli in the context of trauma exposure.
Design, Setting, and Participants In this cross-sectional study, survivors of trauma who completed sociodemographic and posttraumatic symptom assessments and neuroimaging were recruited as part of the Advancing Understanding of Recovery After Trauma (AURORA) study between September 2017 and June 2021. Data analysis was performed from October 25, 2022, to February 15, 2023.
Exposure Neighborhood disadvantage was measured with the Area Deprivation Index (ADI) for each participant home address.
Main Outcomes and Measures Participants completed separate threat and reward tasks during functional magnetic resonance imaging. Diffusion-weighted and high-resolution structural images were also collected. Linear models assessed the association of ADI with reactivity, microstructure, and macrostructure of a priori regions of interest after adjusting for income, lifetime trauma, sex at birth, and age. A moderated-mediation model tested whether ADI was associated with neural activity via microstructural changes and if this was modulated by PTSD symptoms.
Results A total of 280 participants (183 females [65.4%]; mean [SD] age, 35.39 [13.29] years) completed the threat task and 244 participants (156 females [63.9%]; mean [SD] age, 35.10 [13.26] years) completed the reward task. Higher ADI (per 1-unit increase) was associated with greater insula (t274 = 3.20; β = 0.20; corrected P = .008) and anterior cingulate cortex (ACC; t274 = 2.56; β = 0.16; corrected P = .04) threat-related activity after considering covariates, but ADI was not associated with reward reactivity. Greater disadvantage was also associated with altered microstructure of the cingulum bundle (t274 = 3.48; β = 0.21; corrected P = .001) and gray matter morphology of the ACC (cortical thickness: t273 = −2.29; β = −0.13; corrected P = .02; surface area: t273 = 2.53; β = 0.13; corrected P = .02). The moderated-mediation model revealed that ADI was associated with ACC threat reactivity via cingulum microstructural changes (index of moderated mediation = −0.02). However, this mediation was only present in individuals with greater PTSD symptom severity (at the mean: β = −0.17; standard error = 0.06, t= −2.28; P = .007; at 1 SD above the mean: β = −0.28; standard error = 0.08; t = −3.35; P < .001).
Conclusions and Relevance In this study, neighborhood disadvantage was associated with neurobiology that supports threat processing, revealing associations of neighborhood disadvantage with neural susceptibility for PTSD and suggesting how altered structure-function associations may complicate symptoms. Future work should investigate specific components of neighborhood disadvantage that may be associated with these outcomes
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