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Steven Z George,1,2 Maggie E Horn2 1Duke Clinical Research Institute, Duke University, Durham, NC, USA; 2Departments of Orthopaedic Surgery and Population Health Science, Duke University, Durham, NC, USACorrespondence: Steven Z George, Duke University, 300 Morgan Street, Office 480, Durham, NC, 27707, USA, Tel +1 919-668-0825, Email steven.george@duke.eduAims and Objective: The purpose of this pilot study was to explore whether AIH produces changes in pain sensitivity or in reports of self-reported pain intensity for individuals with low back pain.Methods: In a quasi-experimental, cross-over design we compared participants (n = 9) exposed to normal room air and hypoxia using a commercially available gas blender. The treatment period consisted of 5 consecutive days of randomly assigned to AIH or room air. For the participants initially randomized to AIH there was cross-over to receive 5 more consecutive days of room air. Therefore, this design allowed for between group and within subject assessment of AIH effects. Pain sensitivity was assessed with quantitative sensory testing (QST) for posterior superior iliac spine pressure threshold, plantar thermal threshold, and peak pain ratings. Self-reported pain intensity for low back pain was assessed via the Brief Pain Inventory.Results: There were no between group differences for AIH and room air in pain sensitivity or self-reported pain intensity. In the within subject analyses larger effect sizes favoring AIH were detected for plantar measures of pain sensitivity but not for self-reported pain intensity.Conclusion: This study, while presenting null findings, describes an initial step in determining whether AIH can be used to increase pain relief. Based on this pilot study we offer guidance for future research including study design, AIH dosage, participant selection, and using AIH in combination with non-pharmacologic treatments.Keywords: hypoxia, hypoalgesia, low back pain, pain sensitivity

Maggie E Horn,1 Steven Z George,2 Cai Li,3 Sheng Luo,4 Trevor A Lentz2 1Duke University, Department of Orthopaedic Surgery, Durham, NC, 27701, USA; 2Duke University, Department of Orthopaedic Surgery and Duke Clinical Research Institute, Durham, NC, 27701, USA; 3Yale University, Department of Biostatistics, New Haven, CT, USA; 4Duke University, Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC, USACorrespondence: Maggie E HornDuke University, Department of Orthopaedic Surgery, Box 100402, Durham, NC, 27701, USATel +1 9196841365Email maggie.horn@duke.eduRationale: Risk assessment tools can improve clinical decision-making for individuals with musculoskeletal pain, but do not currently exist for predicting reduction of pain intensity as an outcome from physical therapy.Aims and Objective: The objective of this study was to develop a tool that predicts failure to achieve a 50% pain intensity reduction by 1) determining the appropriate statistical model to inform the tool and 2) select the model that considers the tradeoff between clinical feasibility and statistical accuracy.Methods: This was a retrospective, secondary data analysis of the Optimal Screening for Prediction of Referral and Outcome (OSPRO) cohort. Two hundred and seventy-nine individuals seeking physical therapy for neck, shoulder, back, or knee pain who completed 12-month follow-up were included. Two modeling approaches were taken: a longitudinal model included demographics, presence of previous episodes of pain, and regions of pain in addition to baseline and change in OSPRO Yellow Flag scores to 12 months; two comparison models included the same predictors but assessed only baseline and early change (4 weeks) scores. The primary outcome was failure to achieve a 50% reduction in pain intensity score at 12 months. We compared the area under the curve (AUC) to assess the performance of each candidate model and to determine which to inform the Personalized Pain Prediction (P3) risk assessment tool.Results: The baseline only and early change models demonstrated lower accuracy (AUC=0.68 and 0.71, respectively) than the longitudinal model (0.79) but were within an acceptable predictive range. Therefore, both baseline and early change models were used to inform the P3 risk assessment tool.Conclusion: The P3 tool provides physical therapists with a data-driven approach to identify patients who may be at risk for not achieving improvements in pain intensity following physical therapy.Keywords: persistent pain, risk assessment tool, musculoskeletal pain, risk prediction, psychological factors

Charles W Gay,1 Meryl J Alappattu,1 Rogelio A Coronado,1 Maggie E Horn,1 Mark D Bishop21Rehabilitation Science Doctoral Program, College of Public Health and Health Professions, 2Department of Physical Therapy, University of Florida, Gainesville, FLBackground: Muscle-biased therapies (MBT) are commonly used to treat pain, yet several reviews suggest evidence for the clinical effectiveness of these therapies is lacking. Inadequate treatment parameters have been suggested to account for inconsistent effects across studies. Pain sensitivity may serve as an intermediate physiologic endpoint helping to establish optimal MBT treatment parameters. The purpose of this review was to summarize the current literature investigating the short-term effect of a single dose of MBT on pain sensitivity in both healthy and clinical populations, with particular attention to specific MBT parameters of intensity and duration.Methods: A systematic search for articles meeting our prespecified criteria was conducted using Cumulative Index to Nursing and Allied Health Literature (CINAHL) and MEDLINE from the inception of each database until July 2012, in accordance with guidelines from the Preferred Reporting Items for Systematic reviews and Meta-Analysis. Relevant characteristics from studies included type, intensity, and duration of MBT and whether short-term changes in pain sensitivity and clinical pain were noted with MBT application. Study results were pooled using a random-effects model to estimate the overall effect size of a single dose of MBT on pain sensitivity as well as the effect of MBT, dependent on comparison group and population type.Results: Reports from 24 randomized controlled trials (23 articles) were included, representing 36 MBT treatment arms and 29 comparative groups, where 10 groups received active agents, 11 received sham/inert treatments, and eight received no treatment. MBT demonstrated a favorable and consistent ability to modulate pain sensitivity. Short-term modulation of pain sensitivity was associated with short-term beneficial effects on clinical pain. Intensity of MBT, but not duration, was linked with change in pain sensitivity. A meta-analysis was conducted on 17 studies that assessed the effect of MBT on pressure pain thresholds. The results suggest that MBT had a favorable effect on pressure pain thresholds when compared with no-treatment and sham/inert groups, and effects comparable with those of other active treatments.Conclusion: The evidence supports the use of pain sensitivity measures by future research to help elucidate optimal therapeutic parameters for MBT as an intermediate physiologic marker.Keywords: muscle-biased therapy, pain sensitivity, pressure pain threshold

Objective: Translation of knee osteoarthritis (KOA) clinical practice guidelines (CPGs) to practice remains suboptimal. The primary purpose of this systematic review was to describe the use of implementation strategies to promote KOA CPG-recommended care., Methods: Medline (via PubMed), Embase, CINAHL, and Web of Science were searched from inception to February 23, 2023, and the search was subsequently updated and expanded on January 16, 2024. Implementation strategies were mapped per the Expert Recommendations for Implementing Change taxonomy. Risk of bias (RoB) was assessed using the Cochrane Effective Practice and Organisation of Care criteria. The review was registered prospectively (PROSPERO identifier: CRD42023402383)., Results: Nineteen studies were included in the final review. All (100% [n = 4]) studies that included the domains of "provide interactive assistance," "train and educate stakeholders" (89% [n = 16]), "engage consumers" (87% [n = 13]), and "support clinicians" (79% [n = 11]) showed a change to provider adherence. Studies that showed a change to disability included the domains of "train and educate stakeholders," "engage consumers," and "adapt and tailor to context." Studies that used the domains "train and educate stakeholders," "engage consumers," and "support clinicians" showed a change in pain and quality of life. Most studies had a low to moderate RoB., Conclusion: Implementation strategies have the potential to impact clinician uptake of CPGs and patient-reported outcomes. The implementation context, using an active learning strategy with a patient partner, restructuring funding models, and integrating taxonomies to tailor multifaceted strategies should be prioritized. Further experimental research is recommended to determine which implementation strategies are most effective., (© 2024 American College of Rheumatology.)

Objective: To determine associations between post-emergency department (ED) management pathways and downstream opioid prescriptions in patients seeking care for incident neck and/or back pain., Patients and Methods: We identified patients seeking first-time ED care for neck and/or back pain from January 1, 2013, through November 6, 2017. We reported demographic characteristics and opioid prescriptions across management pathways using descriptive statistics and assessed the relative risk of any opioid prescription 12 months post-ED visit among 5 different post-ED management pathways using Poisson regression adjusted for patient demographic characteristics., Results: Within 12 months after the index ED visit, 58.0% (n=10,949) were prescribed an opioid, with most patients prescribed an opioid within the first week (average daily morphine milligram equivalents of 6.8 mg (SD 9.6 mg). The morphine milligram equivalents decreased to 0.7 mg (SD 8.2 mg) by week 4 and remained consistently less than 1 mg between week 4 and 12 months. Compared with the ED to primary care provider pathway, the relative risk of opioid prescription between 7 days and 12 months after the index ED visit was similar for the ED to physical therapy pathway, higher for both the ED to hospital admission or repeat ED visit pathway (30% increase; relative risk (RR), 1.3; 95% CI, 1.17-1.44) and the ED to specialist pathway (19% increase; RR, 1.19; 95% CI, 1.07-1.33), and lower in the ED with no follow-up visits pathway (41% decrease; RR, 0.59; 95% CI, 0.54-0.65)., Conclusion: In general, more conservative care was associated with lower opioid prescription rates, and escalated care was associated with higher opioid prescription rates., Competing Interests: The authors report no competing interests., (© 2023 The Authors.)

Background: Understanding which patient-reported outcome measures are being collected and utilized in clinical practice and research for patients with neck pain will help to inform recommendations for a core set of measures that provide value to patients and clinicians during diagnosis, clinical decision-making, goal setting and evaluation of responsiveness to treatment. Therefore, the aim of this study was to conduct a review of systematic reviews using a qualitative synthesis on the use of patient-reported outcome measures (PROMs) for patients presenting with neck pain to physical therapy., Methods: An electronic search of systematic reviews and guideline publications was performed using MEDLINE (OVID), Embase (Elsevier), CINAHL Complete (EBSCOhost), and Web of Science (Clarivate) databases to identify reviews that evaluated physical therapy interventions or interventions commonly performed by a physical therapist for individuals with neck pain and included at least one patient-reported outcome measure. The frequency and variability in which the outcome measures were reported among the studies in the review and the constructs for which they measured were evaluated. The evaluation of a core set of outcome measures was assessed. Risk of bias and quality assessment was performed using A Measurement Tool to Assess systematic Reviews 2., Results: Of the initial 7,003 articles, a total of 37 studies were included in the final review. Thirty-one PROMs were represented within the 37 reviews with eleven patient-reported outcome measures in three or more reviews. The eleven PROMs assessed the constructs of disability, pain intensity, psychosocial factors and quality of life. The greatest variability was found amongst individual measures assessing psychosocial factors. Assessment of psychosocial factors was the least represented construct in the included studies. Overall, the most frequently utilized patient reported outcome measures were the Neck Disability Index, Visual Analog Scale, and Numeric Pain Rating Scale. The most frequently used measures evaluating the constructs of disability, pain intensity, quality of life and psychosocial functioning included the Neck Disability Index, Visual Analog Scale, Short-Form-36 health survey and Fear Avoidance Belief Questionnaire respectively. Overall risk of bias and quality assessment confidence levels ranged from critically low (2 studies), low (12 studies), moderate (8 studies), and high (15 studies)., Conclusion: This study identified a core set of patient-reported outcome measures that represented the constructs of disability, pain intensity and quality of life. This review recommends the collection and use of the Neck Disability Index and the Numeric Pain Rating Scale or Visual Analog Scale. Recommendation for a QoL measure needs to be considered in the context of available resources and administrative burden. Further research is needed to confidently recommend a QoL and psychosocial measure for patients presenting with neck pain. Other measures that were not included in this review but should be further evaluated for patients with neck pain are the Patient Reported Outcomes Measurement Information System (PROMIS) Physical function, PROMIS Pain Interference and the Optimal Screening for Prediction of Referral and Outcome Yellow Flag (OSPRO-YF) tool., (© 2023. International Society for Quality of Life Research (ISOQOL).)

Background: Physical function and pain outcomes vary after arthroplasty. We investigated differences in postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) physical function (PF) and pain interference (PI) scores for patients undergoing total knee arthroplasty (TKA) and total hip arthroplasty (THA). We aimed to identify preoperative factors that predict postoperative PROMIS scores., Methods: Patients who underwent TKA and THA from 2014-2020 were eligible. Preoperative variables including demographics, comorbidities, and pain scores were obtained from the medical record. Patients completed surveys measuring postoperative PF and PI. Descriptive statistics and separate linear regression models for each anatomical location were performed to examine factors predicting postoperative PROMIS PF and PI scores., Results: Surveys were completed by 2411 patients (19.5% response rate). Unadjusted mean PF postoperative scores were 47.2 for TKA and 48.8 for THA. Preoperative predictors of lower PF included female sex; body mass index and comorbidities for TKA and THA; and age, tobacco use, and non-White race for THA. Mean PI scores were 47.9 for THA and 49.0 for TKA. Preoperative predictors of increased PI included non-White race and increased body mass index for TKA and THA; higher preoperative pain for TKA; and female sex and increased comorbidity for THA., Conclusions: Postoperative PROMIS scores were similar for TKA and THA, with THA having slightly higher PF and lower PI scores. Regression models using preoperative variables showed similar performance for TKA compared with THA. These findings suggest areas for future development of clinical decision support tools., (© 2023 The Authors.)

Chemically-induced models of intestinal inflammation are a useful tool for the study of immune responses and inflammation. Although well established in mammals, application of these models is currently limited in teleosts. Based on a variety of factors, including genetic diversity, known toxicological sensitivity, and economic importance, we propose salmonids as a model family of fishes for studying intestinal inflammation. We present a rainbow trout model of chemically-induced intestinal inflammation using 2,4,6-trinitrobenzene sulfonic acid (TNBS), assessed through histological analysis of primary and secondary intestinal folding, enterocyte morphology, goblet cell size and frequency, tissue layer thickness, and immune cell infiltration. Twenty-four hours after treatment with one of three concentrations of TNBS, trout developed classic signs of intestinal inflammation, including notably increased thickness of primary and secondary folds, and increased immune cell infiltration as compared to controls. This study provides a simple, reproducible model of rapid TNBS-induction of moderate intestinal inflammation., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

Background: Patient-Reported Outcomes Measurement Information System (PROMIS) domains for sleep disturbance, anxiety, and dyspnea have been under-reported for total joint arthroplasty (TJA). The aims of this study were to report postoperative differences for these domains based on TJA location and chronic pain state. We also investigated whether these domains were associated with physical function and pain interference outcomes., Methods: This was a retrospective, observational study of patients who underwent hip, knee, or shoulder TJA (primary and revision surgeries) at a single academic tertiary referral center. A subset of these patients completed an email-based survey for chronic pain grade (Chronic Pain Grade Scale-Revised) and sleep disturbance, anxiety, dyspnea, physical function, and pain interference (PROMIS short forms). Pre-operative and operative data were extracted from the electronic health record. Data analysis investigated PROMIS domains for differences in TJA location and chronic pain grade. Hierarchical linear regression determined associations of these domains with physical function and pain interference., Results: A total of 2638 individuals provided informed consent and completed the email survey. In the ANOVA models for sleep disturbance, anxiety, and dyspnea, there was no location by chronic pain grade interaction (p > 0.05) and no difference based on TJA location (p > 0.05). There were differences for chronic pain grade (p < 0.01). The poorest postoperative outcome score for each domain was associated with high impact chronic pain. Furthermore, sleep disturbance and dyspnea had the strongest associations with physical function and pain interference (p < 0.01)., Conclusions: Sleep disturbance, anxiety, and dyspnea did not vary based on TJA location, but were associated with postoperative chronic pain grade. Sleep disturbance and dyspnea were strongly associated with commonly reported outcomes of physical function and pain interference. These findings provide guidance for those interested in expanding TJA outcome assessment to include sleep disturbance, anxiety, and/or dyspnea., (© 2022. The Author(s).)

Background: Lumbar spinal stenosis (LSS) is a common degenerative condition that contributes to back and back-related leg pain in older adults. Most patients with symptomatic LSS initially receive non-operative care before surgical consultation. However, there is a scarcity of data regarding prognosis for patients seeking non-surgical care. The overall goal of this project is to develop and evaluate a clinically useful model to predict long-term physical function of patients initiating non-surgical care for symptomatic LSS., Methods: This is a protocol for an inception cohort study of adults 50 years and older who are initiating non-surgical care for symptomatic LSS in a secondary care setting. We plan to recruit up to 625 patients at two study sites. We exclude patients with prior lumbar spine surgeries or those who are planning on lumbar spine surgery. We also exclude patients with serious medical conditions that have back pain as a symptom or limit walking. We are using weekly, automated data pulls from the electronic health records to identify potential participants. We then contact patients by email and telephone within 21 days of a new visit to determine eligibility, obtain consent, and enroll participants. We collect data using telephone interviews, web-based surveys, and queries of electronic health records. Participants are followed for 12 months, with surveys completed at baseline, 3, 6, and 12 months. The primary outcome measure is the 8-item PROMIS Physical Function (PF) Short Form. We will identify distinct phenotypes using PROMIS PF scores at baseline and 3, 6, and 12 months using group-based trajectory modeling. We will develop and evaluate the performance of a multivariable prognostic model to predict 12-month physical function using the least absolute shrinkage and selection operator and will compare performance to other machine learning methods. Internal validation will be conducted using k-folds cross-validation., Discussion: This study will be one of the largest cohorts of individuals with symptomatic LSS initiating new episodes of non-surgical care. The successful completion of this project will produce a cross-validated prognostic model for LSS that can be used to tailor treatment approaches for patient care and clinical trials., (© 2022. The Author(s).)

Background: Physical therapy for neck and low back pain is highly variable despite the availability of clinical practice guidelines (CPG). This review aimed to determine the impact of CPG implementation on patient-level outcomes for spinal pain. Implementation strategies were also examined to determine prevalence and potential impact., Methods: Multiple databases were searched through April 2021 for studies assessing CPG implementation in physical therapy for neck and low back pain. Articles were screened for eligibility. The Modified Downs and Black checklist was utilized to determine study quality. Due to the heterogeneity between studies, a meta-analysis was not performed., Results: Twenty-one studies were included in this review. Implementation strategies were significantly varied between studies. Outcomes pertaining to healthcare utilization, pain, and physical functioning were assessed in relation to the implementation of CPGs. Multiple implementation strategies were identified, with Managing Quality as the most frequently utilized key implementation process. Findings indicate CPG implementation decreased healthcare utilization, but inconsistent results were found with physical functioning and pain outcomes., Conclusions: CPG implementation appears to have a beneficial effect on healthcare utilization outcomes, but may not impact pain and physical functioning outcomes. Effective CPG implementation strategies remain unknown, though utilizing implementation framework may improve outcomes. More research is needed to determine the most effective implementation strategies and effects on pain and physical function outcomes., (© 2022. The Author(s).)

Hip, knee, and shoulder arthroplasty are among the most frequently performed orthopaedic procedures in the United States. High impact and bothersome chronic pain rates following total joint arthroplasty (TJA) are unknown; as are factors that predict these chronic pain outcomes. This retrospective observational study included individuals that had a TJA from January 2014 to January 2020 (n = 2,638). Pre-operative and clinical encounter information was extracted from the electronic health record and chronic pain state was determined by email survey. Predictor variables included TJA location, number of surgeries, comorbidities, tobacco use, BMI, and pre-operative pain intensity. Primary outcomes were high impact and bothersome chronic pain. Rates of high impact pain (95% CI) were comparable for knee (9.8-13.3%), hip (8.3-11.8%) and shoulder (7.6-16.3%). Increased risk of high impact pain included non-white race, two or more comorbidities, age less than 65 years, pre-operative pain scores 5/10 or higher, knee arthroplasty, and post-operative survey completion 24 months or less. Rates of bothersome chronic pain (95% CI) were also comparable for knee (24.9-29.9%) and hip (21.3-26.3%) arthroplasty; but higher for shoulder (26.9-39.6%). Increased risk of bothersome chronic pain included non-white race, shoulder arthroplasty, knee arthroplasty, current or past tobacco use, and being female. PERSPECTIVE: In this cohort more than 1/3rd of individuals reported high impact or bothersome chronic pain following TJA. Non-white race and knee arthroplasty were the only two variables associated with both chronic pain outcomes., (Copyright © 2021 United States Association for the Study of Pain, Inc. Published by Elsevier Inc. All rights reserved.)

Objectives: Characterise the health status of patients newly consulting an orthopaedic specialist across eight clinical subspecialties., Design: Retrospective cohort., Setting: 18 orthopaedic clinics, including 8 subspecialties (14 ambulatory and 4 hospital based) within an academic health system., Participants: 14 910 patients consulting an orthopaedic specialist for a new patient consultation who completed baseline Patient-Reported Outcomes Measurement Information System (PROMIS) measures associated with their appointment from 17 November 2017 to 13 May 2019. Patients were aged 55.72±5.8 years old, and 61.3% were female and 79.3% were Caucasian and 13.4% were black or African American. Patients who did not complete PROMIS measures or cancelled their appointment were excluded from the study., Primary Outcome: PROMIS domains of physical function, pain interference, pain intensity, depression, anxiety, fatigue, sleep disturbance and the ability to participate in social roles., Results: Mean PROMIS scores for physical function were (38.1±9.2), pain interference (58.9±8.1), pain intensity (4.6±2.5), depression (47.9±8.9), anxiety (49.9±9.5), fatigue (50.5±10.3), sleep disturbance (51.1±9.8) and ability to participate in social roles (49.1±10.3) for the entire cohort. Across the clinical subspecialties, neurosurgery, spine and trauma patients were most profoundly affected across almost all domains and patients consulting with a hand specialist reported the least limitations or symptoms across domains. There was a moderate, negative correlation between pain interference and physical functioning (r=-0.59) and low correlations between pain interference with anxiety (r=0.36), depression (r=0.39) as well as physical function and anxiety (r=-0.32) and depression(r=-0.30) and sleep (r=-0.31)., Conclusions: We directly compared clinically meaningful PROMIS domains across eight orthopaedic subspecialties, which would not have been possible with legacy measures alone. These results support PROMIS's utility as a common metric to assess and compare patient health status across multiple orthopaedic subspecialties., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Organisms are exposed to a wealth of chemical information during their development. Some of these chemical cues indicate present or future dangers, such as the presence of predators that feed on either the developing embryos or their nearby parents. Organisms may use this information to modify their morphology or life-history, including hatching timing, or may retain information about risk until it gains relevance. Previous research has shown predation-induced alterations in hatching among embryonic minnows that were exposed to mechanical-injury-released alarm cues from conspecific embryos. Here, we test whether minnows likewise hatch early in response to alarm cues from injured adult conspecifics. We know that embryonic minnows can detect adult alarm cues and use them to facilitate learned recognition of predators; however, it is unknown whether these adult alarm cues will also induce a change in hatching time. Early hatching may allow animals to rapidly disperse away from potential predators, but late hatching may allow animals to grow and develop structures that allow them to effectively escape when they do hatch. Here, we found here that unlike embryonic fathead minnows (Pimephales promelas) exposed to embryonic cues, embryonic minnows exposed to adult alarm cues do not exhibit early hatching. The ability of embryos to recognize adult alarm cues as a future threat, but not a current one, demonstrates sophisticated ontogenetic specificity in the hatching response of embryonic minnows., Competing Interests: The authors have declared that no competing interests exist.

Aims: Patient-reported outcome measures have become an important part of routine care. The aim of this study was to determine if Patient-Reported Outcomes Measurement Information System (PROMIS) measures can be used to create patient subgroups for individuals seeking orthopaedic care., Methods: This was a cross-sectional study of patients from Duke University Department of Orthopaedic Surgery clinics (14 ambulatory and four hospital-based). There were two separate cohorts recruited by convenience sampling (i.e. patients were included in the analysis only if they completed PROMIS measures during a new patient visit). Cohort #1 (n = 12,141; December 2017 to December 2018,) included PROMIS short forms for eight domains (Physical Function, Pain Interference, Pain Intensity, Depression, Anxiety, Sleep Quality, Participation in Social Roles, and Fatigue) and Cohort #2 (n = 4,638; January 2019 to August 2019) included PROMIS Computer Adaptive Testing instruments for four domains (Physical Function, Pain Interference, Depression, and Sleep Quality). Cluster analysis (K-means method) empirically derived subgroups and subgroup differences in clinical and sociodemographic factors were identified with one-way analysis of variance., Results: Cluster analysis yielded four subgroups with similar clinical characteristics in Cohort #1 and #2. The subgroups were: 1) Normal Function: within normal limits in Physical Function, Pain Interference, Depression, and Sleep Quality; 2) Mild Impairment: mild deficits in Physical Function, Pain Interference, and Sleep Quality but with Depression within normal limits; 3) Impaired Function, Not Distressed: moderate deficits in Physical Function and Pain Interference, but within normal limits for Depression and Sleep Quality; and 4) Impaired Function, Distressed: moderate (Physical Function, Pain Interference, and Sleep Quality) and mild (Depression) deficits., Conclusion: These findings suggest orthopaedic patient subgroups differing in physical function, pain, and psychosocial distress can be created from as few as four different PROMIS measures. Longitudinal research is necessary to determine whether these subgroups have prognostic validity. Cite this article: Bone Jt Open  2021;2(7):493-502.

Background: The integration of Patient Reported Outcome Measures (PROMs) into clinical care presents many challenges for health systems. PROMs provide quantitative data regarding patient-reported health status. However, the most effective model for collecting PROMs has not been established. Therefore the purpose of this study is to report the development and preliminary evaluation of the standardized collection of PROMs within a department of orthopedic surgery at a large academic health center., Methods: We utilized the Users' Guide to Integrating Patient-Reported Outcomes in Electronic Health Records by Gensheimer et al., 2018 as a framework to describe the development of PROMs collection initiative. We framed our initiative by operationalizing the three aspects of PROM collection development: Planning, Selection, and Engagement. Next, we performed a preliminary evaluation of our initiative by assessing the response rate of patients completing PROMs (no. of PROMs completed/no. of PROMs administered) across the entire department (18 clinics), ambulatory clinics only (14 clinics), and hospital-based clinics only (4 clinics). Lastly, we reported on the mean response rates for the top 5 and bottom 5 orthopaedic providers to describe the variability across providers., Results: We described the development of a fully-integrated, population health based implementation strategy leveraging the existing resources of our local EHR to maximize clinical utility of PROMs and routine collection. We collected a large volume of PROMs over a 13 month period (n = 10,951) across 18 clinical sites, 7 clinical specialties and over 100 providers. The response rates varied across the department, ranging from 29 to 42%, depending on active status for the portal to the electronic health record (MyChart). The highest single provider mean response rate was 52%, and the lowest provider rate was 13%. Rates were similar between hospital-based (26%) and ambulatory clinics (29%)., Conclusions: We found that our standardized PROMs collection initiative, informed by Gensheimer et al., achieved scope and scale, but faced challenges in achieving a high response rate commensurate with existing literature. However, most studies reported a targeted recruitment strategy within a narrow clinical population. Further research is needed to elucidate the trade-off between scalability and response rates in PROM collection initiatives.

Background: The Patient-Reported Outcomes Measurement Information System Ⓡ (PROMIS Ⓡ ) is a dynamic system of psychometrically sound patient-reported outcome (PRO) measures. There has been a recent increase in the use of PROMIS measures, yet little has been written about the reporting of these measures in the field of orthopedics. The purpose of this study was to conduct a systematic review to determine the uptake of PROMIS measures across orthopedics and to identify the type of PROMIS measures and domains that are most commonly used in orthopedic research and practice., Methods: We searched PubMed, Embase, and Scopus using keywords and database-specific subject headings to capture orthopedic studies reporting PROMIS measures through November 2018. Our inclusion criteria were use of PROMIS measures as an outcome or used to describe a population of patients in an orthopedic setting in patients ≥ 18 years of age. We excluded non-quantitative studies, reviews, and case reports., Results: Our final search yielded 88 studies published from 2013 through 2018, with 57% (50 studies) published in 2018 alone. By body region, 28% (25 studies) reported PROMIS measures in the upper extremity (shoulder, elbow, hand), 36% (32 studies) reported PROMIS measures in the lower extremity (hip, knee, ankle, foot), 19% (17 studies) reported PROMIS measures in the spine, 10% (9 studies) reported PROMIS measures in trauma patients, and 6% (5 studies) reported PROMIS measures in general orthopedic patients. The majority of studies reported between one and three PROMIS domains (82%, 73 studies). The PROMIS Computerized Adaptive Test (CAT) approach was most commonly used (81%, 72 studies). The most frequently reported PROMIS domains were physical function (81%, 71 studies) and pain interference (61%, 54 studies)., Conclusion: Our review found an increase in the reporting of PROMIS measures over the recent years. Utilization of PROMIS measures in orthopedic populations is clinically appropriate and can facilitate communication of outcomes across different provider types and with reduced respondent burden., Registration: The protocol for this systematic review was designed in accordance with the PRISMA guidelines and is registered with the PROSPERO database (CRD42018088260).

Purpose of Review: The purpose of this systematic review is to evaluate the current literature in patients undergoing spine surgery in the cervical, thoracic, and lumbar spine to determine the available risk assessment tools to predict the patient-centered outcomes of pain, disability, physical function, quality of life, psychological disposition, and return to work after surgery., Recent Findings: Risk assessment tools can assist surgeons and other healthcare providers in identifying the benefit-risk ratio of surgical candidates. These tools gather demographic, medical history, and other pertinent patient-reported measures to calculate a probability utilizing regression or machine learning statistical foundations. Currently, much is still unknown about the use of these tools to predict quality of life, disability, and other factors following spine surgery. A systematic review was conducted using PRISMA guidelines that identified risk assessment tools that utilized patient-reported outcome measures as part of the calculation. From 8128 identified studies, 13 articles met inclusion criteria and were accepted into this review. The range of c-index values reported in the studies was between 0.63 and 0.84, indicating fair to excellent model performance. Post-surgical patient-reported outcomes were identified in the following categories (n = total number of predictive models): return to work (n = 3), pain (n = 9), physical functioning and disability (n = 5), quality of life (QOL) (n = 6), and psychosocial disposition (n = 2). Our review has synthesized the available evidence on risk assessment tools for predicting patient-centered outcomes in patients undergoing spine surgery and described their findings and clinical utility.

Background: Patients seek care from physical therapists for neck pain but it is unclear what the association of the timing of physical therapy (PT) consultation is on 1-year healthcare utilization and costs. The purpose of this study was to compare the 1-year healthcare utilization and costs between three PT timing groups: patients who consulted a physical therapist (PT) for neck pain within 14 days (early PT consultation), between 15 and 90 days (delayed PT consultation) or between 91 and 364 days (late PT consultation)., Methods: A retrospective cohort of 308 patients (69.2% female, ages 48.7[±14.5] years) were categorized into PT timing groups. Descriptive statistics were calculated for each group. In adjusted regression models, 1-year healthcare utilization of injections, imaging, opioids and costs were compared between groups., Results: Compared to early PT consultation, the odds of receiving an opioid prescription (aOR = 2.79, 95%CI: 1.35-5.79), spinal injection (aOR = 4.36, 95%CI:2.26-8.45), undergoing an MRI (aOR = 4.68, 95%CI:2.25-9.74), X-ray (aOR = 2.97, 95%CI:1.61-5.47) or CT scan (aOR = 3.36, 95%CI: 1.14-9.97) were increased in patients in the late PT consultation group. Similar increases in risk were found in the delayed group (except CT and Opioids). Compared to the early PT consultation group, mean costs were $2172 ($557, $3786) higher in the late PT contact group and $1063 (95%CI: $ 138 - $1988) higher in the delayed PT consultation group., Discussion: There was an association with the timing of physical therapy consultation on healthcare utilization and costs, where later consultation was associated with increases costs and healthcare utilization. This study examined the association of timing of physical therapy consultation on costs and healthcare utilization, but not the association of increased access to physical therapy consultation. Therefore, the findings warrant further investigation to explore the effects of increased access to physical therapy consultation on healthcare utilization and costs in a prospective study.

Excitation-inhibition balance is critical for optimal brain function, yet the mechanisms underlying the tuning of inhibition from different populations of inhibitory neurons are unclear. Here, we found evidence for two distinct pathways through which excitatory neurons cell-autonomously modulate inhibitory synapses. Synapses from parvalbumin-expressing interneurons onto hippocampal pyramidal neurons are regulated by neuronal firing, signaling through L-type calcium channels. Synapses from somatostatin-expressing interneurons are regulated by NMDA receptors, signaling through R-type calcium channels. Thus, excitatory neurons can cell-autonomously regulate their inhibition onto different subcellular compartments through their input (glutamatergic signaling) and their output (firing). Separately, while somatostatin and parvalbumin synapses onto excitatory neurons are both dependent on a common set of postsynaptic proteins, including gephyrin, collybistin, and neuroligin-2, decreasing neuroligin-3 expression selectively decreases inhibition from somatostatin interneurons, and overexpression of neuroligin-3 selectively enhances somatostatin inhibition. These results provide evidence that excitatory neurons can selectively regulate two distinct sets of inhibitory synapses., Competing Interests: The authors declare no conflict of interest.

The purpose of this study was to compare the immediate change in temporal summation of heat pain (TSP) between spinal manipulation (SMT) and spinal mobilization (MOB) in healthy volunteers. Ninety-two volunteers (24 male; 23.8 ± 5.3 years) were randomized to receive SMT, MOB, or no treatment (REST) for 1 session. Primary outcomes were changes in TSP, measured at the hand and foot, immediately after the session. A planned subgroup analysis investigated effects across empirically derived TSP clusters. For the primary outcome there were no differences in the immediate change in TSP measured at the foot between SMT and MOB, however, both treatments were superior to the REST condition. In the subgroup analysis the response to a standard TSP protocol was best characterized by 3 clusters: 52% no change (n = 48, 52%); facilitatory response (n = 24, 26%), and inhibitory response (n = 20, 22%). There was a significant Time × Treatment group × Cluster interaction for TSP measured at the foot. The inhibitory cluster showed the greatest attenuation of TSP after SMT and MOB compared with REST. These data suggest lumbar manual therapies of different velocities produce a similar localized attenuation of TSP, compared with no treatment. Attenuation of localized pain facilitatory processes by manual therapies was greatest in pain-free individuals who show an inhibitory TSP response., Perspective: The attenuation of pain facilitatory measures may serve an important underlying role in the therapeutic response to manual therapies. Identifying patients in pain who still have an inhibitory capacity (ie, an inhibitory response subgroup) may be useful clinically in identifying the elusive "manual therapy" responder., (Copyright © 2017 American Pain Society. Published by Elsevier Inc. All rights reserved.)

Objective: To examine patients seeking care for neck pain to determine associations between the type of provider initially consulted and 1-year health care utilization., Patients and Methods: A retrospective cohort of 1702 patients (69.25% women, average age, 45.32±14.75 years) with a new episode of neck pain who consulted a primary care provider, physical therapist (PT), chiropractor (DC), or specialist from January 1, 2012, to June 30, 2013, was analyzed. Descriptive statistics were calculated for each group, and subsequent 1-year health care utilization of imaging, opioids, surgery, and injections was compared between groups., Results: Compared with initial primary care provider consultation, patients consulting with a DC or PT had decreased odds of being prescribed opioids within 1 year from the index visit (DC: adjusted odds ratio [aOR], 0.54; 95% CI, 0.39-0.76; PT: aOR, 0.59; 95% CI, 0.44-0.78). Patients consulting with a DC additionally demonstrated decreased odds of advanced imaging (aOR, 0.43; 95% CI, 0.15-0.76) and injections (aOR, 0.34; 95% CI, 0.19-0.56). Initiating care with a specialist or PT increased the odds of advanced imaging (specialist: aOR, 2.96; 95% CI, 2.01-4.38; PT: aOR, 1.57; 95% CI, 1.01-2.46), but only initiating care with a specialist increased the odds of injections (aOR, 3.21; 95% CI, 2.31-4.47)., Conclusion: Initially consulting with a nonpharmacological provider may decrease opioid exposure (PT and DC) over the next year and also decrease advanced imaging and injections (DC only). These data provide an initial indication of how following recent practice guidelines may influence health care utilization in patients with a new episode of neck pain.

Neuroligins (NLGNs) are postsynaptic cell adhesion molecules that interact trans-synaptically with neurexins to mediate synapse development and function. NLGN2 is only at inhibitory synapses while NLGN3 is at both excitatory and inhibitory synapses. We found that NLGN3 function at inhibitory synapses in rat CA1 depends on the presence of NLGN2 and identified a domain in the extracellular region that accounted for this functional difference between NLGN2 and 3 specifically at inhibitory synapses. We further show that the presence of a cytoplasmic tail (c-tail) is indispensible, and identified two domains in the c-tail that are necessary for NLGN function at inhibitory synapses. These domains point to a gephyrin-dependent mechanism that is disrupted by an autism-associated mutation at R705 and a gephyrin-independent mechanism reliant on a putative phosphorylation site at S714. Our work highlights unique and separate roles for the extracellular and intracellular regions in specifying and carrying out NLGN function respectively., Competing Interests: The authors declare that no competing interests exist.

Background: Neck pain is one of the most common reasons for entry into the healthcare system. Recent increases in healthcare utilization and medical costs have not correlated with improvements in health. Therefore there is a need to identify management strategies for neck pain that are effective for the patient, cost efficient for the payer and provided at the optimal time during an episode of neck pain., Methods: One thousand five hundred thirty-one patients who underwent physical therapist management with a primary complaint of non-specific neck pain from January 1, 2008 to December 31, 2012 were identified from the Rehabilitation Outcomes Management System (ROMS) database at Intermountain Healthcare. Patients reporting duration of symptoms less than 4 weeks were designated as undergoing "early" management and patients with duration of symptoms greater than 4 weeks were designated as receiving "delayed" management. These groups were compared using binary logistic regression to examine odds of achieving Minimal Clinically Important Difference (MCID) on the Neck Disability Index (NDI) and Numerical Pain Rating Scale (NPRS). Separate generalized linear modeling examined the effect of timing of physical therapist management on the metrics of value and efficiency., Results: Patients who received early physical therapist management had increased odds of achieving MCID on the NDI (aOR = 2.01, 95 % CI 1.57, 2.56) and MCID on the NPRS (aOR = 1.82, 95 % CI 1.42, 2.38), when compared to patients receiving delayed management. Patients who received early management demonstrated the greatest value in decreasing disability with a 2.27 percentage point change in NDI score per 100 dollars, best value in decreasing pain with a 0.38 point change on the NPRS per 100 dollars. Finally, patients receiving early management were managed more efficiently with a 3.44 percentage point change in NDI score per visit and 0.57 point change in NPRS score per visit., Conclusions: These findings suggest that healthcare systems that provide pathways for patients to receive early physical therapist management of neck pain may realize improved patient outcomes, greater value and higher efficiency in decreasing disability and pain compared to delayed management. Further research is needed to confirm this assertion.

Sequential patterns of prefrontal activity are believed to mediate important behaviors, e.g., working memory, but it remains unclear exactly how they are generated. In accordance with previous studies of cortical circuits, we found that prefrontal microcircuits in young adult mice spontaneously generate many more stereotyped sequences of activity than expected by chance. However, the key question of whether these sequences depend on a specific functional organization within the cortical microcircuit, or emerge simply as a by-product of random interactions between neurons, remains unanswered. We observed that correlations between prefrontal neurons do follow a specific functional organization-they have a small-world topology. However, until now it has not been possible to directly link small-world topologies to specific circuit functions, e.g., sequence generation. Therefore, we developed a novel analysis to address this issue. Specifically, we constructed surrogate data sets that have identical levels of network activity at every point in time but nevertheless represent various network topologies. We call this method shuffling activity to rearrange correlations (SHARC). We found that only surrogate data sets based on the actual small-world functional organization of prefrontal microcircuits were able to reproduce the levels of sequences observed in actual data. As expected, small-world data sets contained many more sequences than surrogate data sets with randomly arranged correlations. Surprisingly, small-world data sets also outperformed data sets in which correlations were maximally clustered. Thus the small-world functional organization of cortical microcircuits, which effectively balances the random and maximally clustered regimes, is optimal for producing stereotyped sequential patterns of activity., (Copyright © 2016 the American Physiological Society.)

Unlabelled: Spinal manipulative therapy (SMT) is effective for some individuals experiencing low back pain; however, the mechanisms are not established regarding the role of placebo. SMT is associated with changes in pain sensitivity, suggesting related altered central nervous system response or processing of afferent nociceptive input. Placebo is also associated with changes in pain sensitivity, and the efficacy of SMT for changes in pain sensitivity beyond placebo has not been adequately considered. We randomly assigned 110 participants with low back pain to receive SMT, placebo SMT, placebo SMT with the instructional set "The manual therapy technique you will receive has been shown to significantly reduce low back pain in some people," or no intervention. Participants receiving the SMT and placebo SMT received their assigned intervention 6 times over 2 weeks. Pain sensitivity was assessed prior to and immediately following the assigned intervention during the first session. Clinical outcomes were assessed at baseline and following 2 weeks of participation in the study. Immediate attenuation of suprathreshold heat response was greatest following SMT (P = .05, partial η(2) = .07). Group-dependent differences were not observed for changes in pain intensity and disability at 2 weeks. Participant satisfaction was greatest following the enhanced placebo SMT. This study was registered at www.clinicaltrials.gov under the identifier NCT01168999., Perspective: The results of this study indicate attenuation of pain sensitivity is greater in response to SMT than the expectation of receiving an SMT. These findings suggest a potential mechanism of SMT related to lessening of central sensitization and may indicate a preclinical effect beyond the expectations of receiving SMT., (Copyright © 2014 American Pain Society. Published by Elsevier Inc. All rights reserved.)

Traumatic events generate some of the most enduring forms of memories. Despite the elevated lifetime prevalence of anxiety disorders, effective strategies to attenuate long-term traumatic memories are scarce. The most efficacious treatments to diminish recent (i.e., day-old) traumata capitalize on memory updating mechanisms during reconsolidation that are initiated upon memory recall. Here, we show that, in mice, successful reconsolidation-updating paradigms for recent memories fail to attenuate remote (i.e., month-old) ones. We find that, whereas recent memory recall induces a limited period of hippocampal neuroplasticity mediated, in part, by S-nitrosylation of HDAC2 and histone acetylation, such plasticity is absent for remote memories. However, by using an HDAC2-targeting inhibitor (HDACi) during reconsolidation, even remote memories can be persistently attenuated. This intervention epigenetically primes the expression of neuroplasticity-related genes, which is accompanied by higher metabolic, synaptic, and structural plasticity. Thus, applying HDACis during memory reconsolidation might constitute a treatment option for remote traumata., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The purpose of this paper was to examine the relationship of sex and pain-related fear in pain intensity reports to thermal stimuli and whether sex differences in reported pain intensity were mediated by pain-related fear. 177 participants, 124 female (23.5 ± 4.5 years old), filled out a demographic and fear of pain questionnaire (FPQ-III). Experimental pain testing was performed using thermal stimuli applied to the lower extremity. Participants rated the intensity of pain using the numerical pain rating scale (NPRS). Independent t-tests, Sobel's test, and linear regression models were performed to examine the relationships between sex, fear of pain, and pain sensitivity. We found significant sex differences for thermal pain threshold temperatures (t = 2.04,  P = 0.04) and suprathreshold pain ratings for 49°C (t = -2.12,  P = 0.04) and 51°C (t = -2.36,  P = 0.02). FPQ-severe score mediated the effect of suprathreshold pain ratings of 49° (t = 2.00,  P = 0.05), 51° (t = 2.07,  P = 0.04), and pain threshold temperatures (t = -2.12,  P = 0.03). There are differences in the pain sensitivity between sexes, but this difference may be mediated by baseline psychosocial factors such as fear of pain.

Background. The flexion relaxation ratio (FRR) has been suggested as a measure of muscular performance in patients with low back pain (LBP). The purpose of this study was to investigate whether the FRR was responsive to acute LBP produced from a delayed onset muscle soreness (DOMS) protocol. Methods. Fifty-one pain-free volunteers performed DOMS to induce LBP. Current pain intensity, trunk flexion range of motion (ROM), and passive straight leg raise (SLR) were measured at baseline, 24 and 48 hours after DOMS. Participants were categorized into pain groups based on reported current pain intensity. Changes in FRR, trunk flexion ROM, and SLR ROM were examined using two-way repeated measures analysis of variance. Results. Pain group was not found to have a significant effect on FRR (F 1,29 = 0.054, P = 0.818), nor were there any two-way interactions for changes in FRR. The pain group had decreased trunk flexion ROM compared to the minimal pain group (F 1,38 = 7.21, P = 0.011), but no decreases in SLR ROM (F 1,38 = 3.51, P = 0.057) over time. Interpretation. There were no differences in FRR based on reported pain intensity of LBP from a DOMS protocol. The responsiveness of FRR might be limited in patients with acute onset LBP of muscular origin.

Background: Our purpose was to develop an induced musculoskeletal pain model of acute low back pain and examine the relationship among pain, disability and fear in this model., Methods: Delayed onset muscle soreness was induced in 52 healthy volunteers (23 women, 17 men; average age 22.4 years; average BMI 24.3) using fatiguing trunk extension exercise. Measures of pain intensity, unpleasantness, and location, and disability, were tracked for one week after exercise., Results: Pain intensity ranged from 0 to 68 with 57.5% of participants reporting peak pain at 24 hours and 32.5% reporting this at 48 hours. The majority of participants reported pain in the low back with 33% also reporting pain in the legs. The ratio of unpleasantness to intensity indicated that the sensation was considered more unpleasant than intense. Statistical differences were noted in levels of reported disability between participants with and without leg pain. Pain intensity at 24 hours was correlated with pain unpleasantness, pain area and disability. Also, fear of pain was associated with pain intensity and unpleasantness. Disability was predicted by sex, presence of leg pain, and pain intensity; however, the largest amount of variance was explained by pain intensity (27% of a total 40%). The second model, predicting pain intensity only included fear of pain and explained less than 10% of the variance in pain intensity., Conclusions: Our results demonstrate a significant association between pain and disability in this model in young adults. However, the model is most applicable to patients with lower levels of pain and disability. Future work should include older adults to improve the external validity of this model.

Motivation: Gene silencing, also called RNA interference, requires reliable assessment of silencer impacts. A critical task is to find matches between silencer oligomers and sites in the genome, in accordance with one-to-many matching rules (G-U matching, with provision for mismatches). Fast search algorithms are required to support silencer impact assessments in procedures for designing effective silencer sequences., Results: The article presents a matching algorithm and data structures specialized for matching searches, including a kernel procedure that addresses a Boolean version of the database task called the skyline search. Besides exact matches, the algorithm is extended to allow for the location-specific mismatches applicable in plants. Computational tests show that the algorithm is significantly faster than suffix-tree alternatives., Availability: Source code, executable, data and test results are freely available at ftp://ftp.csiro.au/Horn/RapidMatch.

Unlabelled: The purpose of this study was to determine whether session-specific measures of negative pain-related affect would account for longitudinal variability in the ratings of the evoked thermal pain. Pain-free subjects rated pain evoked on the posterior leg using thermal stimuli of 45 degrees , 47 degrees , 49 degrees , and 51 degrees C on 3 occasions, each separated by 2 weeks. Session-specific negative pain-related affect measures were also collected. Ratings of pain decreased significantly with repeated testing, demonstrating a systematic change in rating from the first to second sessions that ranged from a mean of 5.3 at 47 degrees C to 9.1 at 49 degrees C. In addition, large random variation occurred across all sessions, resulting in minimal detectable change ranging from 14 to 27. The least variability occurred when a mean rating of the 4 temperatures was used. Session-specific measures of pain-related affect decreased with repeated testing; however, the significant between-subject variability in both rating of pain and pain-related affect were not related to each other. No associations were identified between psychological measures and variability in rating of evoked pain. Future studies of the variability in ratings should consider other factors such as attentional focus., Perspective: The individual variability in thermal rating was not explained by individual variation in session-specific measures of negative pain-related affect. The results of this study support the use of repeated baseline measures of thermal stimuli when feasible. When this is not possible, the variability in ratings of thermal stimuli over multiple sessions is reduced when the mean of multiple temperatures is used., (Copyright 2010 American Pain Society. Published by Elsevier Inc. All rights reserved.)

The availability of foods low in sugar content yet high in flavour is critically important to millions of individuals conscious of carbohydrate intake for diabetic or dietetic purposes. Brazzein is a sweet protein occurring naturally in a tropical plant that is impractical to produce economically on a large scale, thus limiting its availability for food products. We report here the use of a maize expression system for the production of this naturally sweet protein. High expression of brazzein was obtained, with accumulation of up to 4% total soluble protein in maize seed. Purified corn brazzein possessed a sweetness intensity of up to 1200 times that of sucrose on a per weight basis. In addition, application tests demonstrated that brazzein-containing maize germ flour could be used directly in food applications, providing product sweetness. These results demonstrate that high-intensity sweet protein engineered into food products can give sweetener attributes useful in the food industry.

Expression of industrial enzymes in transgenic plants offers an alternative system to fungal fermentation for large-scale production. Very high levels of expression are required to make the enzymes cost-effective. We tested several parameters to determine the best method for achieving high levels of expression for a fungal laccase gene. Transgenic maize plants were generated using an Agrobacterium-mediated system. The molecular parameters that induced the highest expression were the maize embryo-preferred globulin 1 promoter and targeting of the protein to the cell wall. Two independent transgenic events that yielded multiple clonal plants were characterized in detail. Independent transgenic events 01 and 03 contained two or one copies of T-DNA, respectively. Plants derived from a single transgenic event varied in expression level, and the variation in expression levels was heritable. Within the seed, expression in these plants was primarily within the embryo, and was associated with seed browning and limited germination. High oil germplasm was used to increase germination, as well as to assist in increasing expression 20-fold in five generations through breeding and selection.

The number and types of antibodies expressed in plants has increased steadily since the first reports of this accomplishment in the 1980s, illustrating the versatility of plants as a production system for antibodies. Many recent reviews have detailed the antibody forms that have been derived from plant expression systems. This contribution focuses on the remaining challenges to develop plant-derived therapeutic antibodies into products, and some of the progress that is being made in addressing these challenges.

The prevalence of gall stones was studied prospectively by abdominal ultrasound examination in 131 patients with sickle cell disease aged 10-65 years. Of 95 patients with homozygous sickle cell disease, 55 (58%) had gall stones or had had a cholecystectomy. Gall stones were present in four out of 24 (17%) patients with haemoglobin S + C disease and two out of 12 (17%) with haemoglobin S beta thalassaemia. The presence of gall stones was not related to sex, geographical origin, or haematological variables and was not associated with abnormal results of liver function tests. Symptoms typical of biliary colic were reported by 32 out of 47 adult patients with gall stones, and cholecystitis or cholestasis was diagnosed in 18. Cholecystectomy was performed in 29 patients with good relief of symptoms in most cases. Postoperative complications were common, occurring in 10 of the 28 patients who could be evaluated, but not generally serious; they were considerably lessened by a preoperative exchange transfusion that reduced the haemoglobin S concentration to below 40%. It is suggested that all patients with sickle cell disease should be screened for gall stones and that elective cholecystectomy should be performed in those with symptoms or complications.

The role of respiratory viral infection in wheezy bronchitis was studied in 163 children, aged 0-12 years, in a London general practice. Virological investigations were also performed when these same children had acute upper respiratory illness without wheeze. A virus was isolated in 146 (26.4%) of 554 episodes of wheezy bronchitis, rhinoviruses accounting for almost half of the isolations. The relative frequency with which individual viruses were isolated in wheezy bronchitis was similar to that in acute upper respiratory illness in 180 other children who had never had wheezy bronchitis. The large number of isolations of rhinoviruses in wheezy bronchitis is probably due to their numerous serotypes and the absence of cross-immunity between them. Our findings have confirmed that infection by respiratory viruses can provoke wheezy bronchitis in certain children, in whom host factors are an important predeterminant. In children with a previous history of wheezy bronchitis infection by rhinoviruses was associated significantly more often with such an episode than with upper respiratory illness. The maturation of protective mechanisms, including the acquisition of specific immunity to a progressively larger number of viruses, could explain the fall in the age-incidence of wheezy bronchitis.

The role of viruses and M. pneumoniae in episodes of acute respiratory illness in childhood has been studied in a London general practice. The total isolation rate was 31-7 per cent, but the rate varied from 32-6 per cent in upper respiratory infections to 64-0 per cent in pneumonia. The clinical features associated with infection were influenced not only by the type of agent but also by age and other host factors in infected children. Rhinoviruses were more commonly isolated than any other agent and were frequently associated with wheezy bronchitis.

Sputum, nasal swabs, and throat swabs were obtained from 22 children aged between 5 and 15 years during 72 attacks of wheezy bronchitis. A virus, most commonly a rhinovirus, was isolated in 49% of all episodes and in 64% of 22 severe episodes requiring treatment with corticosteroids; the isolation rate was higher early in the illness than later. Virus was recovered more often from sputum than from the nose or throat, suggesting that viral replication occurs freely in the lower respiratory tract: the cytological findings in sputum were compatible with an inflammatory response to viral infection. Pathogenic bacteria appeared to play a minor role compared with viruses, and routine antibiotic treatment was probably of little value in moost cases. The significance of the results is discussed in relation to the pathogenesis of childhood wheezy bronchitis.

The prevalences of asthma and atopy were examined in the families of 77 asthmatic and 87 control children attending a London general practice. The prevalence of asthma in first degree relatives of asthmatic children was found to be significantly higher than in relatives of control children, and this difference was more pronounced for relatives of atopic probands than for relatives of non-atopic probands. Among the relatives of asthmatics, atopic asthma was more common than non-atopic asthma, irrespective of the atopic status of the proband. However, among the relatives of control children, neither the prevalence of asthma nor the atopic status of the asthmatic relatives was influenced by the atopic status of the proband. These findings support the hypothesis that asthma and atopy are inherited independently. Although atopy itself does not predispose to asthma, it may enhance a genetic susceptibility to the condition, thus increasing the likelihood that the latter will be expressed.

The respiration of dark-grown Nicotiana glutinosa L. cells in liquid suspension culture was found to be highly cyanide resistant and salicylhydroxamic acid (SHAM) sensitive, indicative of an active alternative respiratory pathway. This was especially true during the lag and logarithmic phases of the 14-day growth cycle. Mitochondria isolated from logarithmically growing cells exhibited active oxidation of malate, succinate, and exogenous NADH. Oxidation of all three substrates had an optimum pH of 6.5 and all were highly resistant to inhibited by cyanide and sensitive to SHAM. Respiratory control was exhibited by all three substrates but only if SHAM was present to block the alternative pathway and divert electrons to the phosphorylating cytochrome pathway. The cyanide-resistant oxidation of exogenous NADH has previously only been associated with Arum spadix mitochondria. Coemergence during evolution of the alternative respiratory pathway and the exogenous NADH dehydrogenase in plant mitochondria as a possible mechanism for removal of cytoplasmic NADH is proposed. Evidence is presented which suggests that mitochondrial assays should be performed at pH 6.5.

The family histories relating to asthma and wheezy bronchitis were examined in 77 asthmatic, 78 wheezy bronchitic, and 87 control children, aged between 1 and 12 years. The percentage of children with at least one asthmatic relative was significantly greater in the asthmatic and wheezy bronchitic probands than in the controls; and asthma was more prevalent in the relatives of both groups of wheezy probands than in the relatives of controls. Similarly, the percentage of children with at least one wheezy bronchitic relative tended to be greater in asthmatic and wheezy bronchitic probands than in the controls; and wheezy bronchitis tended to be more prevalent in the relatives of both groups of wheezy probands than in the relatives of controls. However these differences did not reach significance. The strong similarities between asthmatic and wheezy bronchitic children in their family histories of asthma and wheezy bronchitis suggest that these two forms of wheezy illness share a common genetic defect.

Highly chlorophyllous photomixotrophic callus was visually selected from callus originating from soybean (Glycine max (L.) Merr. var. Corsoy) cotyledon. Suspension cultures initiated from this callus became photoautotrophic under continuous light with an atmosphere of 5% CO(2) (balance air). Dry weight increases of 1000 to 1400% in the 2-week subculture period have been observed. The cellular Chl content ranged from 4.4 to 5.9 micrograms per milligram dry weight which is about 75 to 90% of the Chl content in soybean leaves under equivalent illumination (300 micro-Einsteins per square meter per second).No growth can be observed in the dark in sucrose-lacking medium or in the presence of 0.5 micromolar 3-(3,4-dichlorophenyl)-1,1-dimethylurea, a concentration which does not inhibit heterotrophic growth (on sucrose). Photoautotrophic growth has an absolute requirement for elevated CO(2) concentrations (>1%). During the 14-day subculture period, growth (fresh weight and dry weight) is logarithmic. Photosynthesis quickly increases after day 4, reaching a peak of 83 micromoles CO(2) incorporated per milligram Chl per hour while dark respiration decreases 90% from day 2 to day 6. The pH of the growth medium quickly drops from 7.0 to 4.5 before slowly increasing to 5.0 by day 14. At this pH range and light intensity (200-300 microEinsteins per square meter per second), no O(2) evolution could be detected although at high pH and light intensity O(2) evolution was recorded.

The sickle cell diseases are a major health problem for Afro-Caribbean peoples. Neonatal detection and prophylactic management can reduce mortality and morbidity in childhood. A study was therefore conducted analysing the results of the first two years of cord blood screening in the Camberwell health area. Thirteen cases of sickle cell disease and two of haemoglobin (Hb)C disease were identified among 2202 non-white infants screened. The carrier state, sickle cell trait (HbAS), was present in 11.9% and HbC trait (HbAC) in 4.1% of Afro-Caribbean infants. The incidence of disease and of carrier states was much higher in West Africans than in Caribbeans. The wider implications of screening and the need for a comprehensive plan of care are emphasised.

A case is described of a 59-year-old woman presenting with multiple renal tubular defects. The aminoaciduria was of a generalized type. When investigated initially the only feature of myelomatosis was urinary Bence-Jones protein. Two years later radiologically classical multiple myelomatosis developed and rapidly progressed to the patient's death nine months later.