Number of musculoskeletal pain sites leads to increased long-term healthcare contacts and healthcare related costs - a Danish population-based cohort study

BACKGROUND

People with musculoskeletal pain seek more healthcare than the general population, however little is known about the long-term effect on healthcare use. The aim of this study was to examine the consequences of number of musculoskeletal pain sites on long-term care-seeking and healthcare-related costs and explore how health anxiety influences this relationship.

METHODS

We conducted a Danish population-based longitudinal cohort study of 4883 participants combining self-reported survey data from 2008 with ten-year follow-up data from national health registers. Using a causal inference framework, we examined associations between number of pain sites (range 0-7)/level of health anxiety (high/low level) and face-to-face healthcare contacts/healthcare-related costs. Data were analyzed using negative binomial regression with generalized estimating equations. Regression models were adjusted for sex, age, duration of pain, level of education, comorbidity, personality traits, risk of depression, marital status, physical job exposure, and previous healthcare utilization.

RESULTS

For each additional pain site general healthcare contacts (Incidence Rate Ratio (IRR): 1.04 (95% CI: 1.03-1.05)), healthcare-related costs (IRR: 1.06 (95% CI: 1.03-1.08) and musculoskeletal healthcare contacts (IRR: 1.11 (95% CI:1.09-1.14) increased. Those with high levels of health anxiety at baseline had a slightly higher number of general healthcare contacts (IRR 1.06 (1.01-1.11), independent of number of pain sites. However, level of anxiety did not influence the effect of number of pain sites on any healthcare use or cost outcomes.

CONCLUSIONS

We found evidence for a causal association between increasing number of pain sites and greater healthcare use and cost, and high levels of health anxiety did not increase the strength of this association. This suggests that number of pain sites could be a potential target for biopsychosocial interventions in order to reduce the need for future care-seeking.

P–385 The relationship between systemic oestradiol and vaginal microbiota composition in miscarriage and normal pregnancy

Study question

Is there an association between serum oestradiol, vaginal microbial composition and pregnancy outcome in the early first trimester?

Summary answer

In women with a vaginal microbiome deplete of Lactobacillus species at the time of Pregnancy of Uncertain Viability (IPUV), higher serum oestradiol associates with livebirth.

What is known already

During pregnancy, oestradiol mediates vaginal mucosal properties and increases glycogen deposition in epithelial cells which is thought to support colonisation of Lactobacillus species. Low levels of Lactobacillus associates with adverse outcomes such as miscarriage and preterm birth. The direct relationship between systemic oestradiol and the vaginal microbiome has never been studied in pregnancy. However studies have shown a positive correlation between serum oestrone, vaginal glycogen and Lactobacillus abundance in menopausal women.

Study design, size, duration

This was a prospective cohort study where one-hundred women were recruited in early pregnancy at the time of IPUV and donated paired blood and vaginal samples. 40 women had an eventual miscarriage, 58 had a livebirth and two pregnancies were terminated. All 100 women donated one paired serum and vaginal sample at this time point, and 22 women with Lactobacillus depletion at the time of IPUV donated further longitudinal vaginal samples.

Participants/materials, setting, methods

Participants were recruited from an Early Pregnancy Unit and underwent transvaginal ultrasound assessment of their pregnancy. Serum samples were analysed with an immunoassay on a ROCHE COBAS E411 analyser for Oestradiol (pg/ml) and Progesterone (ng/ml). Bacterial DNA was extracted from paired vaginal swabs and sequenced using Illumina MiSeq sequencing of 16S rRNA gene amplicons.

Main results and the role of chance

Lactobacillus dominance of the vagina was associated with higher serum levels of E2 and progesterone compared to depletion (E2=398pg/ml vs 302pg/ml(p = 0.02), P4=23.1ng/ml vs 17ng/ml(p = 0.02)). E2 and P4 were positively correlated (r = 0.6, p < 0.05). At species level, L. crispatus dominance associated with significantly higher levels of E2 compared to high-diversity communities (468pg/ml vs 302pg/ml(p = 0.03) but no such relationship was observed for P4. Both E2 and P4 levels were lower in women who eventually miscarried. However there was no significant difference in the vaginal bacterial composition at genera or species level at this early gestational age (P = 0.08) regardless of per vaginal bleeding. However in women with Lactobacillus depleted microbiota, livebirth was associated with significantly higher E2 levels compared to women suffering miscarriage (212pg/ml in miscarriage vs 395pg/ml in livebirth, p = 0.003) (OR = 22.4 P = 0.004). In 22 women who had Lactobacillus depletion at the time of IPUV (7 with an eventual outcome of miscarriage, and 15 with an eventual outcome of livebirth), longitudinal vaginal bacterial DNA sequencing was performed. In 7/15 women with livebirth, and higher E2 levels, the microbial composition changed to become more Lactobacillus dominant during pregnancy, whereas in those with miscarriage, only 1/7 changed to become Lactobacillus dominant.

Limitations, reasons for caution

In this study, serum oestradiol levels were compared to the local vaginal bacterial environment. The ideal would be to study local vaginal oestradiol, glycogen and the bacterial composition.

Wider implications of the findings: In contrast to previous studies in menopause where low oestrogen levels associate with the vaginal microbial composition, this study uses the high oestradiol environment of early pregnancy to study the mechanistic relationship between oestradiol and vaginal Lactobacillus abundance.

Trial registration number

NA

O-129 Lactobacillus deplete vaginal microbial composition is associated with chromosomally normal miscarriage and local inflammation

Study question

To investigate the vaginal microbial composition and the local immune response in chromosomally normal and abnormal miscarriages and compare this to uncomplicated pregnancies delivering at term.

Summary answer

We show that euploid miscarriage is associated with a significantly higher prevalence of Lactobacillus spp. deplete vaginal microbial communities compared to aneuploid miscarriage.

What is known already

Emerging evidence supports the role of the vaginal microbiota in adverse pregnancy outcome, but the underlying mechanisms are poorly understood. A dominance of Lactobacillus spp. in pregnancy provides protection against pathogenic bacteria by producing lactic acid and antimicrobial compounds. A depletion in Lactobacillus spp. is often linked to adverse pregnancy outcomes.Current work also implicates the reproductive tract microbiota as a key modulator of local inflammatory and immune pathways. We have previously shown that miscarriage is associated with vaginal dysbiosis but without knowledge of the cytogenetic status of those miscarriages or the local immune profile.

Study design, size, duration

This study was a prospective observational cohort study based at Queen Charlotte’s & Chelsea Hospital, Early Pregnancy Unit, London between March 2014-February 2019. Vaginal swabs were collected from the posterior vaginal fornix of 167 patients.

Participants/materials, setting, methods

We used 16S rRNA gene based metataxonomics to interrogate the vaginal microbiota in a cohort of 167 women, 93 miscarriage patients (54 euploid and 39 aneuploid using molecular cytogenetics) and 74 women who delivered at term and correlate this with the aneuploidy status of the miscarriages. We also measured the concentrations of IL-2, IL-4, IL-6, IL-8, TNF-α, IFN-γ, IL-1β, IL-18 and IL-10 in cervical vaginal fluid using Human Magnetic Luminex Screening Assay (8-plex).

Main results and the role of chance

We show that euploid miscarriage is associated with a significantly higher prevalence of Lactobacillus spp. deplete vaginal microbial communities compared to aneuploid miscarriage (P=0.008). In women having Lactobacillus spp. deplete vaginal microbial communities, euploid miscarriage associates with higher concentrations of pro-inflammatory cytokines IL-1β, IL-8, IL-6 (P<0.001, P=0.01 and P<0.001 respectively) and lower concentrations of anti-inflammatory cytokines IL10 (P<0.001) when compared to viable term pregnancy. We identified Prevotella bivia and Streptococcus as particularly common in euploid miscarriage and as drivers of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α). Co-occurrence network analyses revealed low levels of co-occurrence between Lactobacillus crispatus and other organisms and strong co-occurrence between Streptococcal species. Our data show a combination of both an adverse vaginal microbiota and a cytokine response to it influences early pregnancy outcome. Although this may be a reflection of intrinsic maternal immune response, it appears that the cytokine response is largely driven by the bacterial taxa present in the vagina, which presents an opportunity for specific, directed intervention. The negative co-occurrence between L.crispatus and all other organisms suggests a possible therapeutic role for probiotics containing this organism. The influence of Streptococci also suggests a potential benefit of targeted antibiotics with probiotics for some patients.

Limitations, reasons for caution

There were no longitudinal samples in this cohort and our results are based on the assumption that the vaginal microbial composition is stable throughout the first trimester.Future longitudinal studies with larger sample sizes are needed to corroborate these findings and provide insights to the mechanisms that trigger the inflammatory response.

Wider implications of the findings

These findings support the hypothesis that the vaginal microbiota plays an important aetiological role in euploid miscarriage and may represent a target to modify the risk of pregnancy loss.

Trial registration number

n/a

How to use remote patient monitoring successfully in cardiac and pulmonary patients: a realist review

Funding Acknowledgements

Type of funding sources: Public hospital(s). Main funding source(s): Queensland Health

Background

Remote patient monitoring (RPM) is an underutilised telehealth intervention that can enhance self-management of cardiovascular and pulmonary disease and reduce acute care use. However, studies of effectiveness of RPM interventions vary widely. This study aimed to explain the variation in outcomes related to RPM interventions within cardiac and pulmonary populations. Specifically, we aimed to answer why some RPM interventions are more successful than others in reducing demand on acute care services.

Methods

In brief, search terms for remote monitoring and acute care utilisation were used across three electronic databases: PubMed, EMBASE and CINAHL. The search, conducted in October 2020, included articles published in the last five years (2015-2020). Articles were included if they used RPM to monitor an individual’s biometrics (e.g. heart rate, blood pressure) from a distance while they are not in hospital. Realist review methodology was used to enable exploration of how, why and for whom interventions do and do not work.  Outcomes were evaluated to determine contextual factors and potential mechanisms that led to variation in cardiac and pulmonary intervention outcomes.

Results

After screening, 91 articles met the eligibility criteria and were included. We found that across a broad range of RPM interventions 31 factors emerged that are likely to impact the effectiveness of cardiac and pulmonary RPM innovations. These were synthesised into six theories of intervention success: 1) targeting populations at high risk; 2) accurately detecting a decline in health; 3) providing responsive and timely care; 4) personalising care; 5) enhancing self-management and, 6) ensuring collaborative and coordinated care.

Conclusion

 While RPM interventions are complex, if they are designed with patients, providers and the implementation setting in mind and with the key variables identified within this review  incorporated, it is more likely that they will be effective at reducing acute hospital events.

Mental health and wellbeing coordinators in primary schools to support student mental health: protocol for a quasi-experimental cluster study

Background

Half of mental health disorders begin before the age of 14, highlighting the importance of prevention and early-intervention in childhood. Schools have been identified globally by policymakers as a platform to support good child mental health; however, the majority of the research is focused on secondary schools, with primary schools receiving very little attention by comparison. The limited available evidence on mental health initiatives in primary schools is hindered by a lack of rigorous evaluation. This quasi-experimental cluster study aims to examine the implementation and effectiveness of a Mental Health and Wellbeing Co-ordinator role designed to build mental health capacity within primary schools.

Methods

This is a primary (ages 5–12) school-based cluster quasi-experimental study in Victoria, Australia. Before baseline data collection, 16 schools selected by the state education department will be allocated to intervention, and another 16 matched schools will continue as ‘Business as Usual’. In intervention schools, a mental health and well-being coordinator will be recruited and trained, and three additional school staff will also be selected to receive components of the mental health training. Surveys will be completed by consenting staff (at 2-, 5-, 10- and 17-months post allocation) and by consenting parents/carers (at 3-, 10- and 17-months post allocation) in both intervention and business as usual schools. The primary objective is to assess the change in teacher’s confidence to support student mental health and wellbeing using the School Mental Health Self-Efficacy Teacher Survey. Secondary objectives are to assess the indirect impact on systemic factors (level of support, prioritisation of child mental health), parent and teachers’ mental health literacy (stigma, knowledge), care access (school engagement with community-based services), and student mental health outcomes. Implementation outcomes (feasibility, acceptability, and fidelity) and costs will also be evaluated.

Discussion

The current study will examine the implementation and effectiveness of having a trained Mental Health and Wellbeing Coordinator within primary schools. If the intervention increases teachers’ confidence to support student mental health and wellbeing and builds the capacity of primary schools it will improve student mental health provision and inform large-scale mental health service reform.

Trial registration

The trial was retrospectively registered in the Australian New Zealand Clinical Trials Registry (ANZCTR) on July 6, 2021. The registration number is ACTRN12621000873820.

Use of antibiotic coated intramedullary nails in open tibia fractures: A European medical resource use and cost-effectiveness analysis

PURPOSE

In patients with open tibial fractures, bone and wound infections are associated with an increased hospital length of stay and higher costs. The infection risk increases with the use of implants. Innovations to reduce this risk include antibiotic-coated implants. This study models whether the use of a gentamicin-coated intramedullary tibial nail is cost-effective for trauma centers managing patients with a high risk of infection.

EFFICACY

Absolute infection risk and relative risk reduction, by fracture grade, for antibiotic-coated nails compared to standard nails for patients with open tibial fractures were estimated based on the results of a meta-analysis, which assessed the additional benefit of locally-administered prophylactic antibiotics in open tibia fractures treated with implants. The observed efficacy of antibiotic-coated nails in reducing infections was applied in an economic model.

METHODS

The model compared infection rates, inpatient days, theatre usage and costs in high risk patients, with a Gustilo-Anderson (GA) grade III open fracture, for two patient cohorts from a trauma center perspective, with a 1-year time horizon. In one cohort all GAIII patients received a gentamicin-coated nail whilst GAI and GAII patients received a standard nail. All patients in the comparator cohort received a standard nail. Four European trauma centers provided patient-level data (n=193) on inpatient days, procedures and related costs for patients with and without infections.

RESULTS

Using the gentamicin-coated nail in patients at high risk of infection (GAIII) was associated with 75% lower rate of infection and cost savings (€477 - €3.263) for all included centers; the higher cost of the implant was offset by savings from fewer infections, inpatient days (-26%) and re-operations (-10%). This result was confirmed by extensive sensitivity analyses.

CONCLUSIONS

Analyses demonstrated that infection rates and total costs for in-hospital treatment could be potentially reduced by 75% and up to 15% respectively, by using a gentamicin-coated nail in patients at high risk of infection. Fewer infections, reduced inpatient days and re-operations may be potentially associated with use of antibiotic-coated implants. Results are sensitive to the underlying infection risk, with greatest efficacy and cost-savings when the coated implant is used in high risk patients.

Discrimination in the surgical discipline: an international European evaluation (DISDAIN)

Background

Negative workplace experiences (NWPEs), such as gender discrimination, bullying, sexual harassment and ethnic discrimination, are concerns in today’s surgical society. These negative experiences potentially impair surgeons’ performance and might impact patient care or outcomes negatively. This study aimed to assess the experience of NWPEs across the European surgical workforce.

Methods

A prospective online 34-point questionnaire was designed using a combination of Likert scale, multiple-choice and short-answer questions. Invitations were distributed through surgical associations via email/social media between 1 September and 15 November 2019. Data were analysed using non-parametric methods.

Results

Some 840 complete responses were included in the analysis. The distribution across genders and stage of surgical training was even. Of the respondents, 20 per cent (168 respondents) considered quitting their job, 4.5 per cent (38) took time off and 0.5% (4) left surgery due to NWPEs; 12.9 per cent of females and 4.4 per cent of males experienced some form of physical harassment. Females and those in training were significantly more likely to experience or witness gender discrimination and sexual harassment. Just over half of the respondents (448) did not report negative experiences, with most of these (375 respondents) being unaware of whom to report to. Nearly a fifth of respondents felt that NWPEs influenced patient care or outcomes negatively.

Conclusion

NWPEs were frequent, especially among females and those in training. While a substantial proportion of respondents experienced physical harassment, many individuals were unaware of how to raise concerns. Adverse effects on patient outcomes, surgical training and workforce retention indicate a need for urgent action.

Outcomes of biosynthetic absorbable mesh use in high risk CDC Class I ventral hernia repair: a single surgeon series

PURPOSE

Biosynthetic absorbable meshes have emerged as suitable alternatives to permanent synthetic and biologic meshes in complex ventral hernia repair in contaminated wounds. Evidence regarding the use of these products in clean wounds is currently scant. This paper presents a large single surgeon series using GORE^®BIO-A^® (W.L. Gore & Associates, Newark, DE) (Bio-A) tissue reinforcement in high risk patients with predominantly CDC Class I wounds.

METHODS

Retrospective review of a prospectively maintained database of consecutive patients who underwent open ventral hernia repair with biosynthetic absorbable mesh was conducted. Ventral Hernia Working Group (VHWG) classification based on patient demographics and Centers for Disease Control (CDC) wound type were collected prospectively. All patients were followed up for a minimum of 12 months post-operatively.

RESULTS

155 patients were included with a mean post-operative follow up of 29 months (range 12-62 months). Mean age was 61.8 years with an average BMI of 33.5 kg/m². 147 patients (94.9%) were classified as VHWG 2 or 3 based on comorbidities or surgical field contamination. 69% (n = 107) of wounds were designated CDC Class I. Mean hernia size was 119.7cm² with recurrent defects comprising 32.3% (n = 50). Retrorectus mesh repair was achieved in 84.5% of patients (n  = 131). Post-operative wound events occurred in 19.3%. No mesh was explanted. Hernia recurrence rate was 9.0% with a mean time to recurrence of 14 months. There was no significant difference in recurrence rates between clean and contaminated wounds.

CONCLUSION

This study supports the use of Bio-A in high risk ventral hernias, demonstrating a safe and durable repair across all wound classes. Ongoing follow-up continues to monitor for late complications and recurrence.

Naive stem cell blastocyst model captures human embryo lineage segregation

Human naive pluripotent cells can differentiate into extraembryonic trophectoderm and hypoblast. Here we describe a human embryo model (blastoid) generated by self-organization. Brief induction of trophectoderm leads to formation of blastocyst-like structures within 3 days. Blastoids are composed of three tissue layers displaying exclusive lineage markers, mimicking the natural blastocyst. Single-cell transcriptome analyses confirm segregation of trophectoderm, hypoblast, and epiblast with high fidelity to the human embryo. This versatile and scalable system provides a robust experimental model for human embryo research.

Human naive epiblast cells possess unrestricted lineage potential

Classic embryological experiments have established that the early mouse embryo develops via sequential lineage bifurcations. The first segregated lineage is the trophectoderm, essential for blastocyst formation. Mouse naive epiblast and derivative embryonic stem cells are restricted accordingly from producing trophectoderm. Here we show, in contrast, that human naive embryonic stem cells readily make blastocyst trophectoderm and descendant trophoblast cell types. Trophectoderm was induced rapidly and efficiently by inhibition of ERK/mitogen-activated protein kinase (MAPK) and Nodal signaling. Transcriptome comparison with the human embryo substantiated direct formation of trophectoderm with subsequent differentiation into syncytiotrophoblast, cytotrophoblast, and downstream trophoblast stem cells. During pluripotency progression lineage potential switches from trophectoderm to amnion. Live-cell tracking revealed that epiblast cells in the human blastocyst are also able to produce trophectoderm. Thus, the paradigm of developmental specification coupled to lineage restriction does not apply to humans. Instead, epiblast plasticity and the potential for blastocyst regeneration are retained until implantation.

Patient-reported outcome measures (PROMs) use in post-stroke patient care and clinical practice: a realist synthesis protocol

BACKGROUND

There is growing interest in the use of routine patient-reported outcome measures (PROMs) to influence the care of individual patients with stroke. However, there are significant gaps in our understanding as to how PROMs influence post-stroke patient care and clinical practice. This is due to factors including the number of purported uses for PROMs and that PROMs are complex interventions, which attempt to stimulate varied actions or behaviours. Therefore, the objective of this realist synthesis is to offer theory-based explanations as to how PROMs influence post-stroke clinical practice and patient care.

METHODS

This is a protocol for a realist synthesis, which involves three distinct phases: theory building (phase 1), theory testing and refinement (phase 2) and synthesis (phase 3). Phase 1 will develop initial rough programme theories (IRPTs), through literature searches (from January 2000 onwards) of MEDLINE, EMBASE, PsycINFO, CINAHL, Cochrane Library and the grey literature. Only secondary sources will be included that contribute to the development of IRPTs. Only two IRPTs, prioritised by the stakeholder group, will be taken forward to be tested and refined during phase 2. Further novel searches will be employed in phase 2, utilising the same criteria as phase 1; however, phase 2 searches will not utilise grey literature searches, and only primary research studies that contribute to the refinement of programme theories under investigation will be included. Two independent reviewers will screen and select all returned results. The reviewers will code and annotate relevant sources, resulting in 'fragments' to be extracted and graded based on the richness of their contribution to explanation and causal insight. Further, these fragments will be organised into 'Context-Mechanism-Outcome' configurations. Phase 3 of the review will involve the synthesis of context-mechanism-outcome configurations to form middle-range theory-based explanations and developed logic models for stakeholders to understand how PROMs in post-stroke clinical practice and patient care work for whom, how and under what circumstances.

DISCUSSION

The resulting realist synthesis will provide guidance on the implementation of PROMs within routine post-stroke clinical practice and patient care and act as a touchstone for further testing and refinement of PROMs programmes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020138649 .

Impact of a pharmacist-led substance use disorder transitions of care clinic on postdischarge medication treatment retention

BACKGROUND

The Veterans Health Administration (VHA) has made significant improvements in increasing prescribing of medication treatment for opioid use disorder (MOUD) and medication treatment for alcohol use disorder (MAUD); however, several barriers to treatment retention remain. In an effort to improve MOUD/MAUD retention, a Veterans Affairs (VA) facility established a pharmacist-led substance use disorder (SUD) transitions of care telephone clinic for patients discharged from an inpatient hospitalization on MOUD/MAUD, including buprenorphine/naloxone (BUP/NAL) and extended-release (ER) naltrexone injections. Pharmacists within the clinic assess aspects of treatment retention such as medication tolerability, perceived barriers to continuing treatment, status of current prescriptions, and appointment coordination.

OBJECTIVES

The primary objective of this study was to evaluate the impact of a pharmacist-led SUD transitions of care telephone clinic on MOUD/MAUD retention following inpatient initiation in patients with opioid use disorder (OUD) and/or alcohol use disorder (AUD). Secondary objectives included subanalyses of clinic impact on MOUD/MAUD retention based on study medication or diagnoses, health care utilization, and characterization of pharmacist interventions.

METHODS

The study identified patients for inclusion from inpatient units at a VA hospital. The study included patients if they were >18 years of age, had a diagnosis of AUD and/or OUD, and were initiated on ER naltrexone or BUP/NAL during admission and continued at discharge from August 1, 2018, to December 31, 2019. The study excluded patients if they declined clinic involvement, transferred facilities, moved beyond the VA catchment area, or were unable to be reached for initial contact after 3 telephone attempts. The intervention group included patients enrolled in the pharmacist-led SUD transitions of care telephone clinic, while the control group included patients initiated on MOUD/MAUD during admission who were eligible but not referred for clinic enrollment.

RESULTS/CONCLUSIONS

The study identified a total of 150 patients for inclusion (n = 54 intervention group; n = 96 control group). The study observed a statistically significant difference for the primary endpoint of combined 1- and 3-month MOUD/MAUD retention rates as measured by a continuous, multiple-interval measure of medication acquisition (CMA) of ER naltrexone and BUP/NAL for the intervention group vs. control group (1-month: 77.3% vs. 56.8%, p = 0.004; 3-month: 71.4% vs. 48%, p = 0.0002). When analyzed by study medication, we also observed a statistically significant improvement in continuous use of ER naltrexone for those enrolled in the clinic (1-month: 71.4% vs. 45.9%, p = 0.01; 3-month: 66.7% vs. 34.4%, p = 0.0003). The study did not observe any statistically significant improvements for BUP/NAL (1-month: 87.1% vs. 75.8%, p = 0.13; 3-month: 79.4% vs. 68.5%, p = 0.24) or establishment with a BUP/NAL clinic (90.5% vs. 80% patients established, p = 0.46). Likewise, the study did not observe any statistically significant differences for combined emergency department (ED) visits (1-month: 24.1% vs.17.1% patients with ED visit, p = 0.40; 3-month: 31.5% vs. 29.2% patients with ED visit, p = 0.85) or hospitalizations (1-month: 9.3% vs. 14.6% re-hospitalization, p = 0.45; 3-month: 14.8% vs. 26% re-hospitalization, p = 0.15) for those in the intervention group vs. the control group. Overall, the study observed statistically and clinically significant improvements in MOUD/MAUD retention rates for patients enrolled in a pharmacist-led SUD transitions of care telephone clinic.

O15: DISRUPTION OF THE BLOOD-SPINAL CORD BARRIER PREDICTS PERMANENT PARAPLEGIA AFTER THORACOABDOMINAL AORTIC ANEURYSM REPAIR

Introduction

Paraplegia post-thoracoabdominal aortic aneurysm (TAAA) repair remains both a devastating and poorly understood complication. We related temporal changes in cellular and protein composition of cerebrospinal fluid (CSF) to neurological outcomes after TAAA repair to gain mechanistic insights driving paraplegia.

Method

Patients undergoing TAAA repair (open or endovascular) with a CSF drain were prospectively recruited between 2016-2018. CSF was collected pre-operatively and 24-hourly until removal. Daily neurological examinations were performed by blinded neurologists to the study. CSF cell content was characterised by flow cytometry and proteome analysed by tandem-mass-tag proteomics. An in-vivo rat model was modified using 15 minutes of aortic occlusion to produce consistent paraplegia. Rats were analysed neuro-behaviourally and histologically.

Result

CSF was analysed from 52 patients (age: 70.27+/-11.4; 66% male; open (n=9), endovascular (n=43)). 12 developed paraplegia of whom 5 remained permanently-paraplegic. Demographics were comparable between paraplegics, those who recovered and without post-op neurology. Permanent paraplegia was associated with a significant infiltration of CSF CD45+ leucocytes (P<0.0001). Levels of ADVS-1 was >3-fold higher in permanent-paraplegics CSF versus those who recovered (P=0.0008). ADVS-1 >15ng/ml predicted permanent paraplegia with 100% specificity. Pre-treatment with ADVS-1 inhibition significantly improved walking (<0.001) and increased astrocytic staining in the lateral corticospinal, reticulospinal and rubrospinal tracts versus controls (P=0.03, 0.04, 0.04 respectively).

Conclusion

Permanent paraplegia is associated with shedding of ADVS-1 from parenchymal cord into CSF and blood/spinal-cord barrier disruption leading to cord oedema/leucocyte infiltration. Pre-treatment with ADVS-1 inhibition led to neurobehavioural and histological improvements offering translational hope for this devastating complication.

Take-home message

ADVS-1 is a novel biomarker of paraplegia where accurate biomarkers have proven challenging but more importantly it has proven a therapeutic target with genuine translational potential.

Prospects for beyond the Standard Model physics searches at the Deep Underground Neutrino Experiment: DUNE Collaboration

The Deep Underground Neutrino Experiment (DUNE) will be a powerful tool for a variety of physics topics. The high-intensity proton beams provide a large neutrino flux, sampled by a near detector system consisting of a combination of capable precision detectors, and by the massive far detector system located deep underground. This configuration sets up DUNE as a machine for discovery, as it enables opportunities not only to perform precision neutrino measurements that may uncover deviations from the present three-flavor mixing paradigm, but also to discover new particles and unveil new interactions and symmetries beyond those predicted in the Standard Model (SM). Of the many potential beyond the Standard Model (BSM) topics DUNE will probe, this paper presents a selection of studies quantifying DUNE's sensitivities to sterile neutrino mixing, heavy neutral leptons, non-standard interactions, CPT symmetry violation, Lorentz invariance violation, neutrino trident production, dark matter from both beam induced and cosmogenic sources, baryon number violation, and other new physics topics that complement those at high-energy colliders and significantly extend the present reach.

Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{μ}≡(g_{μ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{μ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both μ^{+} and μ^{-}, the new experimental average of a_{μ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

Splenogonadal fusion: aiding detection and avoiding radical orchidectomy

Splenogonadal fusion is a rare benign congenital anomaly in which there is an abnormal connection between the gonad and the spleen. It was first described over 100 years ago with limited reports in the literature since then. Its similarity in presentation to testicular neoplasia poses a significant challenge in diagnosis and management, often resulting in radical orchidectomy. We present the case of a 31-year-old man who presented with a rapidly growing left-sided testicular mass and suspicious ultrasound findings; histology from the subsequent radical inguinal orchidectomy showed findings consistent with splenogonadal fusion. We describe points for consideration in the clinical history, examination and imaging that could suggest splenogonadal fusion, including preoperative technetium-99m-sulfur colloid imaging and intraoperative frozen section evaluation, which may confirm the diagnosis and prevent unnecessary orchidectomy.

Cooperative genetic networks drive embryonic stem cell transition from naïve to formative pluripotency

In the mammalian embryo, epiblast cells must exit the naïve state and acquire formative pluripotency. This cell state transition is recapitulated by mouse embryonic stem cells (ESCs), which undergo pluripotency progression in defined conditions in vitro. However, our understanding of the molecular cascades and gene networks involved in the exit from naïve pluripotency remains fragmentary. Here, we employed a combination of genetic screens in haploid ESCs, CRISPR/Cas9 gene disruption, large‐scale transcriptomics and computational systems biology to delineate the regulatory circuits governing naïve state exit. Transcriptome profiles for 73 ESC lines deficient for regulators of the exit from naïve pluripotency predominantly manifest delays on the trajectory from naïve to formative epiblast. We find that gene networks operative in ESCs are also active during transition from pre‐ to post‐implantation epiblast in utero. We identified 496 naïve state‐associated genes tightly connected to the in vivo epiblast state transition and largely conserved in primate embryos. Integrated analysis of mutant transcriptomes revealed funnelling of multiple gene activities into discrete regulatory modules. Finally, we delineate how intersections with signalling pathways direct this pivotal mammalian cell state transition.

Capture of Mouse and Human Stem Cells with Features of Formative Pluripotency

Pluripotent cells emerge as a naive founder population in the blastocyst, acquire capacity for germline and soma formation, and then undergo lineage priming. Mouse embryonic stem cells (ESCs) and epiblast-derived stem cells (EpiSCs) represent the initial naive and final primed phases of pluripotency, respectively. Here, we investigate the intermediate formative stage. Using minimal exposure to specification cues, we derive stem cells from formative mouse epiblast. Unlike ESCs or EpiSCs, formative stem (FS) cells respond directly to germ cell induction. They colonize somatic tissues and germline in chimeras. Whole-transcriptome analyses show similarity to pre-gastrulation formative epiblast. Signal responsiveness and chromatin accessibility features reflect lineage capacitation. Furthermore, FS cells show distinct transcription factor dependencies, relying critically on Otx2. Finally, FS cell culture conditions applied to human naive cells or embryos support expansion of similar stem cells, consistent with a conserved staging post on the trajectory of mammalian pluripotency.

Prevalence of early hip OA features on MRI in high-impact athletes. The femoroacetabular impingement and hip osteoarthritis cohort (FORCe) study

OBJECTIVE

To compare early hip osteoarthritis (OA) features on magnetic resonance imaging (MRI) in high-impact athletes with and without hip and/or groin pain, and to evaluate associations between early hip OA features, the International Hip Outcome Tool (iHOT33) and Copenhagen Hip and Groin Outcome Score (HAGOS).

DESIGN

This case-control study evaluated data of the femoroacetabular impingement and hip osteoarthritis cohort (FORCe). One hundred and eighty-two symptomatic (hip and/or groin pain >6 months and positive flexion-adduction-internal-rotation (FADIR) test) and 55 pain-free high-impact athletes (soccer or Australian football (AF)) without definite radiographic hip OA underwent hip MRI. The Scoring Hip Osteoarthritis with MRI (SHOMRI) method quantified and graded the severity of OA features. Each participant completed the iHOT33 and HAGOS.

RESULTS

Hip and/or groin pain was associated with higher total SHOMRI (0-96) (mean difference 1.4, 95% CI: 0.7-2.2), labral score (adjusted incidence rate ratio (aIRR) 1.33, 95% CI: 1.1-1.6). Differences in prevalence of cartilage defects, labral tears and paralabral cysts between symptomatic and pain-free participants were inconclusive. There was a lower prevalence of effusion-synovitis in symptomatic participants when compared to pain-free participants (adjusted odds ratio (aOR) 0.46 (95% CI: 0.3-0.8). Early hip OA features were not associated with iHOT33 or HAGOS.

CONCLUSIONS

A complex and poorly understood relationship exists between hip and/or groin pain and early hip OA features present on MRI in high-impact athletes without radiographic OA. Hip and/or groin pain was associated with higher SHOMRI and labral scores.

An international study of public contact with people who have an intellectual disability

BACKGROUND

People with intellectual disability (ID) are often socially isolated, and many experience stigma and discrimination. Increased contact with the general public is thought to overcome prejudices. This large-scale international study had three main aims: to determine the type and frequency of contact that the general public has with people with ID; to identify the personal characteristics of those who have greater contact; and to examine the public's level of comfort at the prospect of having contact with people with ID.

METHOD

Self-completed online questionnaires were administered to nationally representative panels of respondents in 17 countries; totally 24 504 persons. Multivariate analyses were used to identify respondents more likely to have had frequent personal contact with persons with ID from those with infrequent or no contact and those respondents who were most comfortable at meeting a person with ID.

RESULTS

Internationally around one in four of the general population reports having frequent personal contact with people who have an ID although this varied from 7% in Japan to 46% in Panama. The principal forms of contact were through friendships, neighbours or extended family members. Over all countries, volunteering and engagement with Special Olympics were the two main predictors of frequent personal contact followed by employment in the education, health or social care field, being a parent of children under 18 years, playing sports and being employed. People who reported frequent personal contact were also more comfortable at meeting a person with ID.

CONCLUSIONS

This international dataset provides a baseline against which public contact can be compared across countries and changes monitored over time. The findings suggest ways in which greater contact can be promoted and making the public more comfortable at meeting people with ID.

Cancer-Related Mutations Are Not Enriched in Naive Human Pluripotent Stem Cells

Previous analysis of RNA sequencing (RNA-seq) data from human naive pluripotent stem cells reported multiple point "mutations" in cancer-related genes and implicated selective culture conditions. We observed, however, that those mutations were only present in co-cultures with mouse feeder cells. Inspection of reads containing the polymorphisms revealed complete identity to the mouse reference genome. After we filtered reads to remove sequences of mouse origin, the actual incidence of oncogenic polymorphisms arising in naive pluripotent stem cells is close to zero.

Rational design, synthesis and testing of novel tricyclic topoisomerase inhibitors for the treatment of bacterial infections part 1

The alarming reduction in drug effectiveness against bacterial infections has created an urgent need for the development of new antibacterial agents that circumvent bacterial resistance mechanisms. We report here a series of DNA gyrase and topoisomerase IV inhibitors that demonstrate potent activity against a range of Gram-positive and selected Gram-negative organisms, including clinically-relevant and drug-resistant strains. In part 1, we present a detailed structure activity relationship (SAR) analysis that led to the discovery of our previously disclosed compound, REDX05931, which has a minimum inhibitory concentration (MIC) of 0.06 μg mL^-1 against fluoroquinolone-resistant Staphylococcus aureus. Although in vitro hERG and CYP inhibition precluded further development, it validates a rational design approach to address this urgent unmet medical need and provides a scaffold for further optimisation, which is presented in part 2.

Rational design, synthesis and testing of novel tricyclic topoisomerase inhibitors for the treatment of bacterial infections part 2

Building on our previously-reported novel tricyclic topoisomerase inhibitors (NTTIs), we disclose the discovery of REDX07965, which has an MIC90 of 0.5 μg mL-1 against Staphylococcus aureus, favourable in vitro pharmacokinetic properties, selectivity versus human topoisomerase II and an acceptable toxicity profile. The results herein validate a rational design approach to address the urgent unmet medical need for novel antibiotics.

First Measurement of Differential Charged Current Quasielasticlike ν_{μ}-Argon Scattering Cross Sections with the MicroBooNE Detector

We report on the first measurement of flux-integrated single differential cross sections for charged-current (CC) muon neutrino (ν_{μ}) scattering on argon with a muon and a proton in the final state, ^{40}Ar (ν_{μ},μp)X. The measurement was carried out using the Booster Neutrino Beam at Fermi National Accelerator Laboratory and the MicroBooNE liquid argon time projection chamber detector with an exposure of 4.59×10^{19} protons on target. Events are selected to enhance the contribution of CC quasielastic (CCQE) interactions. The data are reported in terms of a total cross section as well as single differential cross sections in final state muon and proton kinematics. We measure the integrated per-nucleus CCQE-like cross section (i.e., for interactions leading to a muon, one proton, and no pions above detection threshold) of (4.93±0.76_{stat}±1.29_{sys})×10^{-38}  cm^{2}, in good agreement with theoretical calculations. The single differential cross sections are also in overall good agreement with theoretical predictions, except at very forward muon scattering angles that correspond to low-momentum-transfer events.

Ursodeoxycholic acid in intrahepatic cholestasis of pregnancy: a secondary analysis of the PITCHES trial

OBJECTIVE

To evaluate whether a particular group of women with intrahepatic cholestasis of pregnancy (ICP), based on their presenting characteristics, would benefit from treatment with ursodeoxycholic acid (UDCA).

DESIGN

Secondary analysis of the PITCHES trial (ISRCTN91918806).

SETTING

United Kingdom.

POPULATION OR SAMPLE

527 women with ICP.

METHODS

Subgroup analyses were performed to determine whether baseline bile acid concentrations or baseline itch scores moderated a woman's response to treatment with UDCA.

MAIN OUTCOME MEASURES

Bile acid concentration and itch score.

RESULTS

In women with baseline bile acid concentrations less than 40 μmol/l, treatment with UDCA resulted in increased post-randomisation bile acid concentrations (geometric mean ratio 1.19, 95% CI 1.00-1.41, P = 0.048). A test of interaction showed no significance (P = 0.647). A small, clinically insignificant difference was seen in itch response in women with a high baseline itch score (-6.0 mm, 95% CI -11.80 to -0.21, P = 0.042), with a test of interaction not showing significance (P = 0.640). Further subgroup analyses showed no significance. Across all women there was a weak relationship between bile acid concentrations and itch severity.

CONCLUSIONS

There was no subgroup of women with ICP in whom a beneficial effect of treatment with UDCA on bile acid concentration or itch score could be identified. This confirms that its routine use in women with this condition for improvement of bile acid concentration or itch score should be reconsidered.

TWEETABLE ABSTRACT

PITCHES: No group of women with ICP has been found in whom UDCA reduces bile acid concentrations or pruritus.

Robotic-assisted total knee arthroplasty demonstrates decreased postoperative pain and opioid usage compared to conventional total knee arthroplasty

Aims

Robotic-assisted total knee arthroplasty (RA-TKA) has been introduced to provide accurate bone cuts and help achieve the target knee alignment, along with symmetric gap balancing. The purpose of this study was to determine if any early clinical benefits could be realized following TKA using robotic-assisted technology.

Methods

In all, 140 consecutive patients undergoing RA-TKA and 127 consecutive patients undergoing conventional TKA with minimum six-week follow-up were reviewed. Differences in visual analogue scores (VAS) for pain at rest and with activity, postoperative opiate usage, and length of stay (LOS) between the RA-TKA and conventional TKA groups were compared.

Results

Patients undergoing RA-TKA had lower average VAS pain scores at rest (p = 0.001) and with activity (p = 0.03) at two weeks following the index procedure. At the six-week interval, the RA-TKA group had lower VAS pain scores with rest (p = 0.03) and with activity (p = 0.02), and required 3.2 mg less morphine equivalents per day relative to the conventional group (p < 0.001). At six weeks, a significantly greater number of patients in the RA-TKA group were free of opioid use compared to the conventional TKA group; 70.7% vs 57.0% (p = 0.02). Patients in the RA-TKA group had a shorter LOS; 1.9 days versus 2.3 days (p < 0.001), and also had a greater percentage of patient discharged on postoperative day one; 41.3% vs 20.5% (p < 0.001).

Conclusion

Patients undergoing RA-TKA had lower pain levels at both rest and with activity, required less opioid medication, and had a shorter LOS.

Targeted rapid testing for SARS-CoV-2 in the emergency department is associated with large reductions in uninfected patient exposure time

Opportunity exists to decrease healthcare-related exposure to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), preserve infection control resources, and increase care capacity by reducing the time to diagnosis of coronavirus disease 2019 (COVID-19). A retrospective cohort analysis was undertaken to measure the effect of targeted rapid molecular testing for SARS-CoV-2 on these outcomes. In comparison with standard platform testing, rapid testing was associated with a 65.6% reduction (12.6 h) in the median time to removal from the isolation cohort for patients with negative diagnostic results. This translated to an increase in COVID-19 treatment capacity of 3028 bed-hours and 7500 fewer patient interactions that required the use of personal protective equipment per week.

GMP-grade neural progenitor derivation and differentiation from clinical-grade human embryonic stem cells

BACKGROUND

A major challenge for the clinical use of human pluripotent stem cells is the development of safe, robust and controlled differentiation protocols. Adaptation of research protocols using reagents designated as research-only to those which are suitable for clinical use, often referred to as good manufacturing practice (GMP) reagents, is a crucial and laborious step in the translational pipeline. However, published protocols to assist this process remain very limited.

METHODS

We adapted research-grade protocols for the derivation and differentiation of long-term neuroepithelial stem cell progenitors (lt-NES) to GMP-grade reagents and factors suitable for clinical applications. We screened the robustness of the protocol with six clinical-grade hESC lines deposited in the UK Stem Cell Bank.

RESULTS

Here, we present a new GMP-compliant protocol to derive lt-NES, which are multipotent, bankable and karyotypically stable. This protocol resulted in robust and reproducible differentiation of several clinical-grade embryonic stem cells from which we derived lt-NES. Furthermore, GMP-derived lt-NES demonstrated a high neurogenic potential while retaining the ability to be redirected to several neuronal sub-types.

CONCLUSIONS

Overall, we report the feasibility of derivation and differentiation of clinical-grade embryonic stem cell lines into lt-NES under GMP-compliant conditions. Our protocols could be used as a flexible tool to speed up translation-to-clinic of pluripotent stem cells for a variety of neurological therapies or regenerative medicine studies.

The Evolution of Ultrasound in Medicine: A Case Report of Point-of-care Ultrasound in the Self-diagnosis of Acute Appendicitis

Introduction

Point-of-care ultrasound (POCUS) education during medical school develops physicians who are properly prepared for the next generation of medicine. The authors present the case of a first-year medical student who self-diagnosed appendicitis using POCUS.

Case Report

A 25-year-old, first-year medical student presented to the emergency department with lower abdominal pain. What seemed like a straightforward appendicitis presentation came with a twist; the student brought self-performed ultrasound imaging of his appendix.

Conclusion

The student’s ultrasound skill set reflects favorably on the rapid evolution of ultrasound teaching in medical education.

A review of social determinants of health for dashboard development for SDG 3.4 for sub-Sahara Africa

Background

All sustainable developmental goals (SDGs) require implementing sustainable strategies and monitoring to track progress. But what is known of sub-Sahara Africa (SSA)'s efforts in following this stride to reduce by 30% mortality from non-communicable diseases (NCDs) through prevention (SDG 3.4), by considering the effect of social determinants of health (SODHs) on type 2 diabetes increasing prevalence?

Methods

Our search produced 2005 unique articles. Only 10 studies were used in the analysis of this study. These studies include 1 from Botswana, 2 from Ghana, 2 from Kenya, 3 from Nigeria and 2 from South Africa. The findings were evaluated in a greater extent.

Results

All studies (100%) showed non-adherence to exercise and poor glycemic control. 7 studies (70%) on education revealed lack of knowledge or misconceptions, 5 studies (50%) with obesity showed a strong linkage between obesity and type 2 diabetes, and 4 studies (40%) on diet, showed diets high in carbohydrates, saturated fats, and sodium predisposition to type 2 diabetes. All studies (100%) linked urbanization with an increased prevalence of type 2 diabetes.

Conclusions

Changes in SODHs seem to be contributing to the growing prevalence of diabetes in SSA. These changes with other key data should be considered and tailored to policy processes, environment, infrastructures, and norms for prevention strategies and informing dashboard development for SDG 3.4.

Key messages

Social determinants of health must reflect in relevant causal pathways, settings, and sectors for preventive intervention such as in taxation; regulation of food advertising, school, and healthcare. Analysis of the effect of the changing social determinants of health on type 2 diabetes, will assist in establishing indicators for the dashboard development for SDG 3.4 for sub-Sahara Africa.

Falling stroke rates during COVID-19 pandemic at a comprehensive stroke center

INTRODUCTION

Although there is evidence to suggest a high rate of cerebrovascular complications in patients with SARS-CoV-2 infection, anecdotal reports indicate a falling rate of new ischemic stroke diagnoses. We conducted an exploratory single-center analysis to estimate the change in number of new stroke diagnoses in our region, and evaluate the proximate reasons for this change during the COVID-19 pandemic at a tertiary care center in New Jersey.

PATIENTS AND METHODS

A Comprehensive Stroke Center prospective cohort was retrospectively analyzed for the number of stroke admissions, demographic features, and short-term outcomes 5 months prior to 3/1/2020 (pre-COVID-19), and in the 6 weeks that followed (COVID-19 period). The primary outcome was the number of new acute stroke diagnoses before and during the COVID-19 period, as well as the potential reasons for a decline in the number of new diagnoses.

RESULTS

Of the 328 included patients, 53 (16%) presented in the COVID-19 period. There was a mean fall of 38% in new stroke diagnoses (mean 1.13/day [SD 1.07] from 1.82/day [SD 1.38], p<0.01), which was related to a 59% decline in the number of daily transfers from referral centers (p<0.01), 25% fewer telestroke consultations (p=0.08), and 55% fewer patients presenting directly to our institution by private vehicle (p<0.01) and 29% fewer patients through emergency services (p=0.09). There was no significant change in the monthly number of strokes due to large vessel occlusion (LVO), however the proportion of new LVOs nearly doubled in the COVID-19 period (38% vs. 21%, p=0.01).

CONCLUSIONS

The observations at our tertiary care center corroborate anecdotal reports that the number of new stroke diagnoses is falling, which seems related to a smaller proportion of patients seeking healthcare services for milder symptoms. These preliminary data warrant validation in larger, multi-center studies.

Falling stroke rates during COVID-19 pandemic at a comprehensive stroke center

INTRODUCTION

Although there is evidence to suggest a high rate of cerebrovascular complications in patients with SARS-CoV-2 infection, anecdotal reports indicate a falling rate of new ischemic stroke diagnoses. We conducted an exploratory single-center analysis to estimate the change in number of new stroke diagnoses in our region, and evaluate the proximate reasons for this change during the COVID-19 pandemic at a tertiary care center in New Jersey.

PATIENTS AND METHODS

A Comprehensive Stroke Center prospective cohort was retrospectively analyzed for the number of stroke admissions, demographic features, and short-term outcomes 5 months prior to 3/1/2020 (pre-COVID-19), and in the 6 weeks that followed (COVID-19 period). The primary outcome was the number of new acute stroke diagnoses before and during the COVID-19 period, as well as the potential reasons for a decline in the number of new diagnoses.

RESULTS

Of the 328 included patients, 53 (16%) presented in the COVID-19 period. There was a mean fall of 38% in new stroke diagnoses (mean 1.13/day [SD 1.07] from 1.82/day [SD 1.38], p<0.01), which was related to a 59% decline in the number of daily transfers from referral centers (p<0.01), 25% fewer telestroke consultations (p=0.08), and 55% fewer patients presenting directly to our institution by private vehicle (p<0.01) and 29% fewer patients through emergency services (p=0.09). There was no significant change in the monthly number of strokes due to large vessel occlusion (LVO), however the proportion of new LVOs nearly doubled in the COVID-19 period (38% vs. 21%, p=0.01).

CONCLUSIONS

The observations at our tertiary care center corroborate anecdotal reports that the number of new stroke diagnoses is falling, which seems related to a smaller proportion of patients seeking healthcare services for milder symptoms. These preliminary data warrant validation in larger, multi-center studies.