Investigating force-time characteristics of prone thoracic SMT and self-reported patient outcome measures: a feasibility study.

BACKGROUND: Spinal manipulative therapy (SMT) is commonly used to treat musculoskeletal conditions, including thoracic spine pain. Applying patient-specific force-time characteristics are believed to be important to improve SMT's effectiveness. Investigating SMT as part of a multimodal approach is fundamental to account for the complexity of chiropractic clinical practice. Therefore, pragmatic investigations balancing minimal disruptions to the clinical encounter at the same time as ensuring a robust data quality with rigorous protocols are needed. Consequently, preliminary studies are required to assess the study protocol, quality of data recorded and the sustainability of such investigation. Therefore, this study examined the feasibility of investigating SMT force-time characteristics and clinical outcome measures in a clinical setting. METHODS: In this mixed-methods study, providers recorded thoracic SMT force-time characteristics delivered to patients with thoracic spinal pain during regular clinical encounters. Self-reported clinical outcomes of pain, stiffness, comfort during the SMT (using an electronic visual analogue scale), and global rating of change scale were measured before and after each SMT application. Feasibility was quantitatively assessed for participant recruitment, data collection and data quality. Qualitative data assessed participants' perceptions on the impact of data collection on patient management and clinical flow. RESULTS: Twelve providers (58% female, 27.3 ± 5.0 years old) and twelve patients (58% female, 37.2 ± 14.0 years old) participated in the study. Enrolment rate was greater than 40%, data collection rate was 49% and erroneous data was less than 5%. Participant acceptance was good with both providers and patients reporting positive experience with the study. CONCLUSIONS: Recording SMT force-time characteristics and self-reported clinical outcome measures during a clinical encounter may be feasible with specific modification to the current protocol. The study protocol did not negatively impact patient management. Specific strategies to optimize the data collection protocol for the development of a large clinical database are being developed.

Characteristics of Forces at the Clinician-Patient and Patient-Table Interfaces During Thoracic Spinal Manipulation in Asymptomatic Adults Are Consistent With Deformable Body Models.

Investigating all forces exerted on the patient's body during high-velocity, low-amplitude spinal manipulative therapy (SMT) remains fundamental to elucidate how these may contribute to SMT's effects. Previous conflicting findings preclude our understanding of the relationship between SMT forces acting at the clinician-patient and patient-table interfaces. This study aimed to quantify forces at the clinician-participant and participant-table interfaces during thoracic SMT in asymptnomatic adults. An experienced clinician provided a posterior to anterior SMT centered to T7 transverse processes using predetermined force-time characteristics to 40 asymptomatic volunteers (20 females; average age = 27.2 [4.9] y). Forces at the clinician-participant interface were recorded by triaxial load cells; whereas, forces at the participant-table interface were recorded by the force-sensing table technology. Preload force, total peak force, time to peak, and loading rate at each interface were analyzed descriptively. Total peak vertical forces at the clinician-participant interface averaged 532 (71) N while total peak forces at the participant-table interface averaged 658 (33) N. Forces at the participant-table interface were, on average, 1.27 (0.25) times larger than the ones at the clinician-participant interface. Larger forces at the participant-table interface compared with the ones at the clinician-participant interface during thoracic SMT are consistent with mathematical models developed to investigate thoracic impact simulating a dynamic force-deflection response.

The Immediate Effect of Spinal Manipulation on Ball Velocity and Neuromuscular Function During an Instep Kick in Former Varsity Soccer Players: A Feasibility Study.

ABSTRACT: Corso, M, Liang, L, Tran, S, Howitt, S, Srbely, J, and Mior, SA. The immediate effect of spinal manipulation on ball velocity and neuromuscular function during an instep kick in former Varsity soccer players: a feasibility study. J Strength Cond Res 36(9): 2558-2565, 2022-Spinal manipulation (SM) has been shown to increase ball velocity (BV) in soccer players. Evidence suggests that SM modulates responses at spinal or cortical levels to enhance force production in asymptomatic populations. No studies have explored the underlying neuromuscular mechanisms contributing to changes in BV post-SM in soccer players. We assessed the feasibility of measuring change in BV and neuromuscular function after SM in former Varsity level soccer players with a pre-post study design. Three to 5 maximal instep kicks were performed before and after SM at the L3-5 level. Ball velocity was measured using high-speed camera. Activation of lower limb and trunk musculature was recorded with electromyography. Outcomes included ease of recruitment, scheduling and data capture, as well as expectation and perception of SM effect and adverse events (AE). Fifteen potential subjects were recruited over 1.5 months. Eleven were scheduled (24-31 years; 8 females, 3 males). Two subjects reported mild AE after maximal voluntary isometric contraction testing. A significant increase in BV (mean change: 1.75 m·s -1 [95% confidence interval: 0.5-3.0]) and a trend to increased peak-activation of knee extensors (90.7%) were observed post-SM. Findings suggest that our recruitment strategy and methodology are feasible in a larger trial with some modifications. Our preliminary findings support previous research by suggesting that increased BV may be mediated through increased activation of knee extensors during the kick. Our findings may offer additional insight into the underlying neuromuscular mechanisms contributing to immediate change in BV post-SM.

Mnemonic Discrimination Deficits in First-Episode Psychosis and a Ketamine Model Suggest Dentate Gyrus Pathology Linked to NMDA Receptor Hypofunction.

BACKGROUND: Converging evidence from neuroimaging and postmortem studies suggests that hippocampal subfields are differentially affected in schizophrenia. Recent studies report dentate gyrus dysfunction in chronic schizophrenia, but the underlying mechanisms remain to be elucidated. Here, we sought to examine if this deficit is already present in first-episode psychosis and if NMDA receptor hypofunction, a putative central pathophysiological mechanism in schizophrenia, experimentally induced by ketamine, would result in a similar abnormality. METHODS: We applied a mnemonic discrimination task selectively taxing pattern separation in two experiments: 1) a group of 23 patients with first-episode psychosis and 23 matched healthy volunteers and 2) a group of 19 healthy volunteers before and during a ketamine challenge (0.27 mg/kg over 10 min, then 0.25 mg/kg/hour for 50 min, 0.01 mL/s). We calculated response bias-corrected pattern separation and recognition scores. We also examined the relationships between task performance and symptom severity as well as ketamine levels. RESULTS: We reported a deficit in pattern separation performance in patients with first-episode psychosis compared with healthy volunteers (p = .04) and in volunteers during the ketamine challenge compared with baseline (p = .003). Pattern recognition was lower in patients with first-episode psychosis than in control subjects (p < .01). Exploratory analyses revealed no correlation between task performance and Repeatable Battery for the Assessment of Neuropsychological Status total scores or positive symptoms in patients with first-episode psychosis or with ketamine serum levels. CONCLUSIONS: We observed a mnemonic discrimination deficit in both datasets. Our findings suggest a tentative mechanistic link between dentate gyrus dysfunction in first-episode psychosis and NMDA receptor hypofunction.

Characterization of thoracic spinal manipulation and mobilization forces in older adults.

BACKGROUND: Spinal mobilization and spinal manipulation are common interventions used by manual therapists to treat musculoskeletal conditions in older adults. Their force-time characteristics applied to older adults' thoracic spine are important considerations for effectiveness and safety but remain unknown. This study aimed to describe the force-time characteristics of posterior-to-anterior spinal mobilization and manipulation delivered to older adults' thoracic spine. METHODS: Twenty-one older adults (≥65 years) with no thoracic pain received posterior-to-anterior thoracic spinal mobilization and/or manipulation with the force characteristics a chiropractor deemed appropriate. Six-degree-of-freedom load cells and an instrumented treatment table recorded the force characteristics of both interventions at the clinician-participant and participant-table interfaces, respectively. Preload force, total peak force, time to peak and loading rate were analyzed descriptively. FINDINGS: Based on data from 18 adults (56% female; average: 70 years old), mean resultant spinal mobilization forces at the clinician-participant interface were: 220 ± 51 N during preload, 323 ± 67 N total peak force, and 312 ± 38 ms time to peak. At the participant-table interface, mobilization forces were 201 ± 50 N during preload, 296 ± 63 N total peak force, and 308 ± 44 ms time to peak. Mean resultant spinal manipulation forces at the clinician-participant interface were: 260 ± 41 N during preload, 470 ± 46 N total peak force, and 165 ± 28 ms time to peak. At the participant table interface, spinal manipulation forces were 236 ± 47 N during preload, 463 ± 57 N total peak force, and 169 ± 28 ms time to peak. INTERPRETATION: Results suggest older adults experience unique, but comparable force-time characteristics during spinal mobilization and manipulation delivered to their thoracic spine compared to the ones delivered to younger adults described in the literature.

Food-Focused Media Literacy for Remotely Acculturating Adolescents and Mothers: A Randomized Controlled Trial of the "JUS Media? Programme".

PURPOSE: Unhealthy eating is a major modifiable risk factor for noncommunicable diseases and obesity, and remote acculturation to U.S. culture is a recently identified cultural determinant of unhealthy eating among adolescents and families in low/middle-income countries. This small-scale randomized controlled trial evaluated the efficacy of the "JUS Media? Programme," a food-focused media literacy intervention promoting healthier eating among remotely acculturating adolescents and mothers in Jamaica. METHODS: Gender-stratified randomization of 184 eligible early adolescents and mothers in Kingston, Jamaica (i.e., 92 dyads: Madolescent.age = 12.79 years, 51% girls) determined 31 "Workshops-Only" dyads, 30 "Workshops + SMS/texting" dyads, and 31 "No-Intervention-Control" dyads. Nutrition knowledge (food group knowledge), nutrition attitudes (stage of nutritional change), and nutrition behavior (24-hour recall) were primary outcomes assessed at four time points (T1/baseline, T2, T3, T4) across 5 months using repeated measures analysis of covariances. RESULTS: Compared to control, families in one or both intervention groups demonstrated significantly higher nutrition knowledge (T3 adolescents, T4 mothers: mean differences .79-1.08 on a 0-6 scale, 95% confidence interval [CI] .12-1.95, Cohen's ds = .438-.630); were more prepared to eat fruit daily (T3 adolescents and mothers: .36-.41 on a 1-5 scale, 95% CI .02-.77, ds = .431-.493); and were eating more cooked vegetables (T4 adolescents and T2 and T4 mothers: .20-.26 on a 0-1 scale, 95% CI -.03-.50, ds = .406-.607). Postintervention focus groups (6-month-delay) revealed major positive impacts on participants' health and lives more broadly. CONCLUSIONS: A food-focused media literacy intervention for remotely acculturating adolescents and mothers can improve nutrition. Replication in Jamaica and extension to the Jamaican diaspora would be useful.

Configurations of Autonomy and Relatedness in a Multiethnic U.S. Sample of Parent-Adolescent Dyads.

Configurations of autonomy and relatedness were explored in 232 adolescent-parent dyads. Youth (58% female) were 13-18 years old and ethnically diverse (38% Latino American, 32% European American, 30% African American). Cluster analysis was used to identify three distinct groups based on youth and parent reports of parental autonomy support and family relatedness. The three clusters differed on key demographics (e.g., parent education and income, immigrant background, ethnicity) and theoretically relevant indicators of family and individual functioning (e.g., parent and youth reports of decision making and family obligations; youth-reported attachment and minor delinquency). Findings provide empirical support for theoretical models of autonomy-relatedness (e.g., Journal of Cross-Cultural Psychology, 36, 2005, 403) and contribute to understanding of how autonomy and relatedness intersect to influence adolescent and family adaptation.

Ketamine induced changes in regional cerebral blood flow, interregional connectivity patterns, and glutamate metabolism.

Several imaging studies have attempted to characterize the contribution of glutamatergic dysfunction to functional dysconnectivity of large-scale brain networks using ketamine models. However, findings from BOLD imaging studies are conflicting, in part because the signal stems from a complex interaction between blood flow, blood volume, and oxygen consumption. We used arterial spin labelling imaging to measure regional cerebral blood flow (rCBF) in a group of healthy volunteers during a saline and during a ketamine infusion. We examined changes in rCBF and interregional connectivity patterns, as well as their associations with clinical symptom severity and Glx (glutamate + glutamine) assessed with magnetic resonance spectroscopy. We report a regionally selective pattern of rCBF changes following ketamine administration and complex changes in interregional connectivity patterns. We also found that the increase in rCBF in the bilateral putamen and left hippocampus was positively correlated with ketamine induced clinical symptom severity while anterior cingulate rCBF during the ketamine challenge was negatively correlated with change in hippocampal Glx. Our study adds to the efforts to empirically confirm putative links between an NMDA receptor blockage and dysconnectivity of large-scale brain networks, specifically the salience, executive control and default mode networks, suggesting that a glutamatergic imbalance may contribute to dysconnectivity. Development of glutamatergic compounds that alleviate disease burden, possibly through normalizing glutamate excess related increased rCBF, is direly needed.

RETRACTED: Mnemonic Discrimination Deficits in First-Episode Psychosis and a Ketamine Model Suggests Dentate Gyrus Pathology Linked to N-Methyl-D-Aspartate Receptor Hypofunction.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). Retraction notice to: "Mnemonic Discrimination Deficits in First-Episode Psychosis and a Ketamine Model Suggests Dentate Gyrus Pathology Linked to N-Methyl-D-Aspartate Receptor Hypofunction" by Nina Vanessa Kraguljac, Matthew Carle, Michael A. Frölich, Steve Tran, Michael A. Yassa, David Matthew White, Abhishek Reddy, and Adrienne Carol Lahti (Biol Psychiatry Cogn Neurosci Neuroimaging 2018; 3:231-238); https://doi.org/10.1016/j.bpsc.2017.02.005. This article has been retracted at the request of Cameron S. Carter, M.D., Editor of Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, with agreement from all authors. The authors discovered an error in the calculation of the response bias­corrected pattern recognition score in this article, which has significantly changed the results for experiment 1. Specifically, the authors discovered that the response bias corrected pattern recognition score was erroneously computed as P('old'|target) minus P('old'|lure) rather than P('old'|target) minus P('old'|foil). After re-running statistical analyses with the correct values, the authors found a significant difference in the response bias­corrected pattern recognition score in healthy volunteers (HV) compared with first-episode psychosis (FEP) patients (HV: 84.13 ± 10.96; FEP: 63.70 ± 21.83; t = 4.01; p < .01) in experiment 1. This finding is not consistent with the original report, where the authors reported no group differences in bias-corrected pattern recognition scores (originally reported values: t = 0.93, p = .36). The authors again found no significant correlations between pattern completion scores and BPRS total, positive, or negative symptom scores or RBANS scores, consistent with the original report. In experiment 2, bias-corrected pattern recognition scores did not differ between the saline and ketamine conditions (saline: 78.29 ± 28.04; ketamine: 73.59 ± 18.94; t = 0.81; p = 0.43), which is consistent with the original report (originally reported values: t = −0.69, p = .50). Contrary to the original report, task performance during the saline and ketamine infusions was no longer correlated at trend level for pattern recognition. Repeat analyses showed no correlations between pattern recognition scores during the ketamine challenge and BPRS total, positive, and negative symptom scores, or ketamine plasma levels at either time point, consistent with the original report. The authors have verified that bias-corrected pattern separation scores were calculated correctly for both experiments in the initial report. This error affects the abstract, the results, Figure 1, and discussion of the manuscript. The authors voluntarily informed the Journal of this honest error upon its discovery. Because of the extent and nature of the changes to the paper, the editors and authors concluded that, to ensure maximum clarity and transparency, the only course of action was to retract this version of the paper. The authors are revising the paper, which the Journal will re-review and consider further for publication.

Responsibility development transfers across contexts: Reciprocal pathways between home and afterschool programs.

We investigated adolescent responsibility across 2 developmental contexts, home and an afterschool program. Longitudinal data were collected from 355 ethnically diverse 11-20-year-old adolescents (M = 15.49; 55.9% female) in 14 project-based programs. Youth rated their responsibility in the program and at home at 4 time points; parents and leaders rated youth at Time 1. The first research objective was to evaluate 3 aspects of construct validity concerning scores of responsibility assessed through a new measure. Analyses provided evidence that program- and home-responsibility scores were distinct (i.e., evidence of the structural aspect of validity); that responsibility scores were invariant across age, gender, and ethnicity (i.e., generalizability evidence); and of external validity based on parent reports (i.e., convergent evidence). The second objective was to examine cross-context transfer of responsibility. A series of cross-lagged structural equation models (SEMs) revealed that higher responsibility in each context (home, program) predicted higher responsibility in the other context, even after controlling for the stability and within-time associations. At the last time interval, the program-to-home path was significantly stronger than the corresponding home-to-program path. The third objective was to assess whether these relations were moderated by adolescent ethnicity, gender, age, or years in the program. Multigroup SEMs revealed that pathways of influence did not differ across groups. Taken as a whole, results indicate that experiences in the 2 contexts of home and program lead to interindividual differences in the development of youth self-reported responsibility, but that affordances for responsibility development across contexts change over time. (PsycINFO Database Record

Risk factors for failed reactivation of a labor epidural for postpartum tubal ligation: a prospective, observational study.

STUDY OBJECTIVE: To determine specific risk factors that increase the failure rate of labor epidurals reactivated for use as a surgical block for postpartum tubal ligation. DESIGN: Prospective, observational study. SETTING: Labor and delivery suite and operating rooms at the Women and Infants Center. PATIENTS: One hundred patients undergoing postpartum tubal ligation with an existing labor epidural that is documented to be within 2 cm of initial placement. MEASUREMENTS: Body mass index, patient satisfaction with her epidural during labor and delivery, time from delivery to reactivation for tubal ligation, depth to loss of resistance, and the need for top-ups during labor were recorded preoperatively. Failure to reactivate was recorded and defined as any patient that (1) did not achieve a T6 level to pinprick, (2) had perceived pain (pain score >3) that required administration of an intravenous opioid or local anesthetic infiltration, or (3) required conversion to general anesthesia. MAIN RESULTS: The overall success rate of reactivation was 78%. Significant risk factors for failure to reactivate were (1) poor patient satisfaction (P = .016), (2) increased time from delivery to reactivation (P = .044), and (3) the need for top-ups during labor and delivery (P = .032). CONCLUSION: Poor satisfaction score of the epidural during labor and delivery, increasing time from delivery to epidural reactivation for tubal ligation, and the need for top-ups during labor and delivery increase the incidence of reactivation failure. No correlation was found with body mass index or loss of resistance and failure to reactivate.

Focus on Methodology: Beyond paper and pencil: Conducting computer-assisted data collection with adolescents in group settings.

Computer-assisted data collection offers advantages over traditional paper and pencil measures; however, little guidance is available regarding the logistics of conducting computer-assisted data collection with adolescents in group settings. To address this gap, we draw on our experiences conducting a multi-site longitudinal study of adolescent development. Structured questionnaires programmed on laptop computers using Audio Computer Assisted Self-Interviewing (ACASI) were administered to groups of adolescents in community-based and afterschool programs. Although implementing ACASI required additional work before entering the field, we benefited from reduced data processing time, high data quality, and high levels of youth motivation. Preliminary findings from an ethnically diverse sample of 265 youth indicate favorable perceptions of using ACASI. Using our experiences as a case study, we provide recommendations on selecting an appropriate data collection device (including hardware and software), preparing and testing the ACASI, conducting data collection in the field, and managing data.

Invited commentary: Positive youth development and human complexity.

The process of positive development for adolescents includes struggling to address a wide variety of complex, often unstated bio-psycho-social-cultural challenges. These include formulating workable values, learning self-regulation, preparation for adult work roles-and innumerable other un-tidy puzzles. Variable-based research can only scratch the surface of how youth go about these processes; nonetheless, systematic longitudinal research like this can provide valuable information about developmental pathways and directions of change. Highlights from these papers include the finding that older youth report more goals aimed at meaningful connection with others and contributing to society; yet also that moral character did not differ by age. The papers suggest that relationships adults, hope, school engagement, participation in out-of-school programs, and intentional self-regulation can serve as mediators of positive development. Yet, a striking finding was that comparatively few youth in the study manifest a pattern of change marked by the coupling of increases in positive youth development and decreases in risk/problem behavior. We believe there is much beneath the surface to be uncovered.

The effect of a lumbar support pillow on lumbar posture and comfort during a prolonged seated task.

BACKGROUND: Several risk factors exist for the development of low back pain, including prolonged sitting and flexed spinal curvature. Several investigators have studied lumbar support devices and spinal curvatures in sitting, however few have investigated a pain population and reported a quantitative measure of comfort. The purpose of the current project was to determine whether a lumbar support pillow, outfitted with a cut-out to accommodate the bulk of posterior pelvic soft tissue volume, is more effective than a standard chair in promoting a neutral spinal posture and improving subjective and objective measures of comfort in healthy individuals and patients with low back pain. METHODS: Twenty eight male participants with and without a history of low back pain sat in a standard office chair and in a chair with the lumbar support pillow for 30 minutes. Lumbar and thoracolumbar postures were measured through electromagnetic markers. Comfort was determined based on the least squares radius of centre of pressure shifting, measured at the buttock-chair interface as well as reported discomfort through visual analog scales. Chair support effects were assessed through ANOVA methods. The study was approved by the Canadian Memorial Chiropractic College research ethics board. RESULTS: There was a main effect of condition on lumbar posture (p = 0.006) and thoracolumbar posture (p = 0.014). In the lumbar region, the support and standard chair differed by 2.88° (95% CI; 1.01-4.75), with the lumbar support being closer to neutral than the standard chair. In the thoracolumbar region, the support and standard chair differed by -2.42° (95% CI; -4.22 to -0.62), with the standard chair being closer to neutral than the support device. The centre of pressure measure was significantly improved with the pillow (p = 0.017), however there were no subjective changes in comfort. CONCLUSIONS: A lumbar support pillow with a cut-out for the posterior pelvic tissues improved an objective measure of comfort in healthy individuals and patients with low back pain. Lumbar flattening was decreased and thoracolumbar curvature was increased. However, angular changes were small and future work is required to determine clinical relevance over the long term. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00754585.

Inhibition of histidine decarboxylase ablates the autocrine tumorigenic effects of histamine in human cholangiocarcinoma.

BACKGROUND: In several tumours the endogenous activity of histidine decarboxylase (HDC), the enzyme stimulating histamine synthesis, sustains the autocrine trophic effect of histamine on cancer progression. Cholangiocarcinoma is a biliary cancer with limited treatment options. Histamine interacts with four G-protein coupled receptors, H1-H4 histamine receptors (HRs). OBJECTIVE: To determine the effects of histamine stimulation and inhibition of histamine synthesis (by modulation of HDC) on cholangiocarcinoma growth. METHODS: In vitro studies were performed using multiple human cholangiocarcinoma lines. The expression levels of the histamine synthetic machinery and HRs were evaluated along with the effects of histamine stimulation and inhibition on cholangiocarcinoma proliferation. A xenograft tumour model was used to measure tumour volume after treatment with histamine or inhibition of histamine synthesis by manipulation of HDC. Vascular endothelial growth factor (VEGF) expression was measured in cholangiocarcinoma cells concomitant with the evaluation of the expression of CD31 in endothelial cells in the tumour microenvironment. RESULTS: Cholangiocarcinoma cells display (1) enhanced HDC and decreased monoamine oxidase B expression resulting in increased histamine secretion; and (2) increased expression of H1-H4 HRs. Inhibition of HDC and antagonising H1HR decreased histamine secretion in Mz-ChA-1 cells. Long-term treatment with histamine increased proliferation and VEGF expression in cholangiocarcinoma that was blocked by HDC inhibitor and the H1HR antagonist. In nude mice, histamine increased tumour growth (up to 25%) and VEGF expression whereas inhibition of histamine synthesis (by reduction of HDC) ablated the autocrine stimulation of histamine on tumour growth (~80%) and VEGF expression. No changes in angiogenesis (evaluated by changes in CD31 immunoreactivity) were detected in the in vivo treatment groups. CONCLUSION: The novel concept that an autocrine loop (consisting of enhanced histamine synthesis by HDC) sustains cholangiocarcinoma growth is proposed. Drug targeting of HDC may be important for treatment of patients with cholangiocarcinoma.