Vitamin E: Not only a single stereoisomer

The recent publication by Azzi and colleagues puts forth the argument that only RRR-α-tocopherol should be considered as vitamin E from a physiological point of view. They base their argument primarily on the assertion that only this form has been used to treat stark vitamin E deficiency in humans (known as AVED, or Ataxia with Vitamin E Deficiency). Azzi et al. also argue that other chemically similar molecules, such as tocopherols other than α-tocopherol and tocotrienols do not provide vitamin E activity. Azzi and colleagues are correct on this second point. An investigation into the biological activities of vitamin E, and the mechanisms behind these activities, confirms that physiological vitamin E activity is limited to certain α-tocopherol forms. However, it is also clear that these activities are not restricted only to the RRR-form but include other 2R-forms as well. Indeed, the α-tocopherol transfer protein (α-TTP), which is critical to mediate vitamin E trafficking and biological activity, and genetic defects of which lead to vitamin E deficiency, binds well to all 2R-forms of α-tocopherol. Furthermore, both RRR-α-tocopherol and the other 2R-forms are maintained in human plasma and distributed to tissues and organs, whereas the 2S-stereoisomers are excreted quickly. As such, in recent years the definition of vitamin E including both 2R- and RRR-α-tocopherol has gained both broad scientific and regulatory acceptance. Consistent with this understanding, we provide evidence that AVED has indeed been treated successfully with forms in addition to RRR-α-tocopherol, again arguing against the restriction of the definition to RRR-α-tocopherol only. Finally, we provide evidence against any safety concerns utilizing the currently accepted definition of vitamin E.

First Measurement of Hard Exclusive π^{-}Δ^{++} Electroproduction Beam-Spin Asymmetries off the Proton

The polarized cross-section ratio σ_{LT^{'}}/σ_{0} from hard exclusive π^{-}Δ^{++} electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2  GeV/10.6  GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5  GeV^{2} up to 7  GeV^{2}. The reaction provides a novel access to the d-quark content of the nucleon and to p→Δ^{++} transition generalized parton distributions. A comparison to existing results for hard exclusive π^{+}n and π^{0}p electroproduction is provided, which shows a clear impact of the excitation mechanism, encoded in transition generalized parton distributions, on the asymmetry.

Reliability of surface electromyographic (sEMG) measures of equine axial and appendicular muscles during overground trot

The reliability of surface electromyography (sEMG) has not been adequately demonstrated in the equine literature and is an essential consideration as a methodology for application in clinical gait analysis. This observational study investigated within-session, intra-subject (stride-to-stride) and inter-subject reliability, and between-session reliability of normalised sEMG activity profiles, from triceps brachii (triceps), latissimus dorsi (latissimus), longissimus dorsi (longissimus), biceps femoris (biceps), superficial gluteal (gluteal) and semitendinosus muscles in n = 8 clinically non-lame horses during in-hand trot. sEMG sensors were bilaterally located on muscles to collect data during two test sessions (session 1 and 2) with a minimum 24-hour interval. Raw sEMG signals from ten trot strides per horse and session were DC-offset removed, high-pass filtered (40 Hz), full-wave rectified, and low-pass filtered (25 Hz). Signals were normalised to peak amplitude and percent stride before calculating intra- and inter-subject ensemble average sEMG profiles across strides for each muscle and session. sEMG profiles were assessed using waveform similarity statistics: the coefficient of variation (CV) to assess intra- and inter-subject reliability and the adjusted coefficient of multiple correlation (CMC) to evaluate between-session reliability. Across muscles, CV data revealed that intra-horse sEMG profiles within- and between-sessions were comparatively more reliable than inter-horse profiles. Bilateral gluteal, semitendinosus, triceps and longissimus (at T14 and L1) and right biceps showed excellent between-session reliability with group-averaged CMCs > 0.90 (range 0.90-0.97). Bilateral latissimus and left biceps showed good between-session reliability with group-averaged CMCs > 0.75 (range 0.78-0.88). sEMG profiles can reliably describe fundamental muscle activity patterns for selected equine muscles within a test session for individual horses (intra-subject). However, these profiles are more variable across horses (inter-subject) and between sessions (between-session reliability), suggesting that it is reasonable to use sEMG to objectively monitor the intra-individual activity of these muscles across multiple gait evaluation sessions at in-hand trot.

First CLAS12 Measurement of Deeply Virtual Compton Scattering Beam-Spin Asymmetries in the Extended Valence Region

Deeply virtual Compton scattering (DVCS) allows one to probe generalized parton distributions describing the 3D structure of the nucleon. We report the first measurement of the DVCS beam-spin asymmetry using the CLAS12 spectrometer with a 10.2 and 10.6 GeV electron beam scattering from unpolarized protons. The results greatly extend the Q^{2} and Bjorken-x phase space beyond the existing data in the valence region and provide 1600 new data points measured with unprecedented statistical uncertainty, setting new, tight constraints for future phenomenological studies.

First Measurement of Λ Electroproduction off Nuclei in the Current and Target Fragmentation Regions

We report results of Λ hyperon production in semi-inclusive deep-inelastic scattering off deuterium, carbon, iron, and lead targets obtained with the CLAS detector and the Continuous Electron Beam Accelerator Facility 5.014 GeV electron beam. These results represent the first measurements of the Λ multiplicity ratio and transverse momentum broadening as a function of the energy fraction (z) in the current and target fragmentation regions. The multiplicity ratio exhibits a strong suppression at high z and an enhancement at low z. The measured transverse momentum broadening is an order of magnitude greater than that seen for light mesons. This indicates that the propagating entity interacts very strongly with the nuclear medium, which suggests that propagation of diquark configurations in the nuclear medium takes place at least part of the time, even at high z. The trends of these results are qualitatively described by the Giessen Boltzmann-Uehling-Uhlenbeck transport model, particularly for the multiplicity ratios. These observations will potentially open a new era of studies of the structure of the nucleon as well as of strange baryons.

Observation of Correlations between Spin and Transverse Momenta in Back-to-Back Dihadron Production at CLAS12

We report the first measurements of deep inelastic scattering spin-dependent azimuthal asymmetries in back-to-back dihadron electroproduction in the deep inelastic scattering process. In this reaction, two hadrons are produced in opposite hemispheres along the z axis in the virtual photon-target nucleon center-of-mass frame, with the first hadron produced in the current-fragmentation region and the second in the target-fragmentation region. The data were taken with longitudinally polarized electron beams of 10.2 and 10.6 GeV incident on an unpolarized liquid-hydrogen target using the CLAS12 spectrometer at Jefferson Lab. Observed nonzero sinΔϕ modulations in ep→e^{'}pπ^{+}X events, where Δϕ is the difference of the azimuthal angles of the proton and pion in the virtual photon and target nucleon center-of-mass frame, indicate that correlations between the spin and transverse momenta of hadrons produced in the target- and current-fragmentation regions may be significant. The measured beam-spin asymmetries provide a first access in dihadron production to a previously unexplored leading-twist spin- and transverse-momentum-dependent fracture function. The fracture functions describe the hadronization of the target remnant after the hard scattering of a virtual photon off a quark in the target particle and provide a new avenue for studying nucleonic structure and hadronization.

ACL microtrauma: healing through nutrition, modified sports training, and increased recovery time

PURPOSE

Sports injuries among youth and adolescent athletes are a growing concern, particularly at the knee. Based on our current understanding of microtrauma and anterior cruciate ligament (ACL) healing characteristics, this clinical commentary describes a comprehensive plan to better manage ACL microtrauma and mitigate the likelihood of progression to a non-contact macrotraumatic ACL rupture.

METHODS

Medical literature related to non-contact ACL injuries among youth and adolescent athletes, collagen and ACL extracellular matrix metabolism, ACL microtrauma and sudden failure, and concerns related to current sports training were reviewed and synthesized into a comprehensive intervention plan.

RESULTS

With consideration for biopsychosocial model health factors, proper nutrition and modified sports training with increased recovery time, a comprehensive primary ACL injury prevention plan is described for the purpose of better managing ACL microtrauma, thereby reducing the incidence of non-contact macrotraumatic ACL rupture among youth and adolescent athletes.

CONCLUSION

Preventing non-contact ACL injuries may require greater consideration for reducing accumulated ACL microtrauma. Proper nutrition including glycine-rich collagen peptides, or gelatin-vitamin C supplementation in combination with healthy sleep, and adjusted sports training periodization with increased recovery time may improve ACL extracellular matrix collagen deposition homeostasis, decreasing sudden non-contact ACL rupture incidence likelihood in youth and adolescent athletes. Successful implementation will require compliance from athletes, parents, coaches, the sports medicine healthcare team, and event organizers. Studies are needed to confirm the efficacy of these concepts.

LEVEL OF EVIDENCE

V.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Adverse neonatal outcome in twin pregnancy complicated by small-for-gestational age: twin vs singleton reference charts

OBJECTIVE

The use of twin-specific vs singleton growth charts in the assessment of twin pregnancy has been controversial. The aim of this study was to assess whether a diagnosis of small-for-gestational age (SGA) made using twin-specific estimated-fetal-weight (EFW) and birth-weight (BW) charts is associated more strongly with adverse neonatal outcomes in twin pregnancies, compared with when the diagnosis is made using singleton charts.

METHODS

This was a cohort study of twin pregnancies delivered at St George's Hospital, London, between January 2007 and May 2020. Twin pregnancies complicated by intrauterine death of one or both twins, fetal aneuploidy or major abnormality, twin-twin transfusion syndrome or twin anemia-polycythemia sequence and those delivered before 32 weeks' gestation, were excluded. SGA was defined as EFW or BW below the 10^th centile, and was assessed using both twin-specific and singleton EFW and BW charts. The main study outcome was composite adverse neonatal outcome. Mixed-effects logistic regression analysis with random pregnancy-level intercepts was used to test the association between SGA classified using the different charts and adverse neonatal outcome.

RESULTS

A total of 1329 twin pregnancies were identified, of which 913 (1826 infants) were included in the analysis. Of these pregnancies, 723 (79.2%) were dichorionic and 190 (20.8%) were monochorionic. Using the singleton charts, 33.3% and 35.7% of pregnancies were classified as SGA based on EFW and BW, respectively. The corresponding values were 5.9% and 5.6% when using the twin-specific charts. Classification as SGA based on EFW using the twin charts was associated significantly with composite adverse neonatal outcome (odds ratio (OR), 4.78 (95% CI, 1.47-14.7); P = 0.007), as compared with classification as appropriate-for-gestational age (AGA). However, classification as SGA based on EFW using the singleton standard was not associated significantly with composite adverse neonatal outcome (OR, 1.36 (95% CI, 0.63-2.88); P = 0.424). Classification as SGA based on EFW using twin-specific standards provided a significantly better model fit than did using the singleton standard (likelihood ratio test, P < 0.001). When twin-specific charts were used, classification as SGA based on BW was associated significantly with a 9.3 times increased odds of composite adverse neonatal outcome (OR, 9.27 (95% CI, 2.86-30.0); P < 0.001). Neonates classified as SGA according to the singleton BW standard but not according to the twin-specific BW standards had a significantly lower rate of composite adverse neonatal outcome than did AGA twins (OR, 0.24 (95% CI, 0.07-0.66); P = 0.009).

CONCLUSIONS

The singleton charts classified one-third of twins as SGA, both prenatally and postnatally. Infants classified as SGA according to the twin-specific charts, but not those classified as SGA according to the singleton charts, had a significantly increased risk of adverse neonatal outcome compared with infants classified as AGA. This study provides further evidence that twin-specific charts perform better than do singleton charts in the prediction of adverse neonatal outcome in twin pregnancies. The use of these charts may reduce misclassification of twins as SGA and improve identification of those that are truly growth restricted. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

The immediate effects of Kinesio Taping on running biomechanics, muscle activity, and perceived changes in comfort, stability and running performance in healthy runners, and the implications to the management of Iliotibial band syndrome

BACKGROUND

Kinesio Taping is frequently used in the management of lower limb injuries, and has been shown to improve pain, function, and running performance. However, little is known about the effects of Kinesio Taping on running biomechanics, muscle activity, and perceived benefits.

RESEARCH QUESTION

This study aimed to explore the immediate effects of Kinesio Taping on lower limb kinematics, joint moments, and muscle activity, as well as perceived comfort, knee joint stability, and running performance in healthy runners.

METHODS

Twenty healthy participants ran at a self-selected pace along a 20-metre runway under three conditions; no tape (NT), Kinesio Tape with tension (KTT), and Kinesio tape without tension (KTNT). Comparisons of peak hip, knee angles and moments, and EMG were analysed during the stance phase of running.

RESULTS

KTT exhibited significant increases in peak hip flexion, peak hip abduction and hip external rotation compared to NT. Moreover, the KTT condition showed a trend towards a decrease in peak hip internal rotation and adduction angle compared to the NT condition. EMG results showed that Tensor Fascia Latae activity decreased with KTT compared with NT, and Gluteus Maximus activity reduced with KTNT when compared with NT. Ten of the 20 participants indicated important improvements in the comfort score, six participants in the knee stability score, and seven participants in the running performance score when using KTT.

SIGNIFICANCE

These results suggest that changes in running biomechanics previously associated with ITBS can be improved with the application of kinesio tape, with the greatest effect seen with the application of kinesio tape with tension. Perceived improvements were seen in comfort, stability and running performance, however these benefits were only seen in half the participants. Further work is required to explore the biomechanical effects and perceived benefits in different patient groups.

Twin chorionicity-specific population birth-weight charts adjusted for estimated fetal weight

OBJECTIVES

To construct chorionicity-specific birth-weight reference charts for dichorionic diamniotic (DCDA) and monochorionic diamniotic (MCDA) twin pregnancies, incorporating estimated-fetal-weight (EFW) data in order to adjust for the relationship between suboptimal growth and preterm delivery. An additional aim was to determine if the inclusion of complicated twin pregnancies impacts on the reference charts produced.

METHODS

The inclusion criteria for this retrospective cohort study were twin pregnancy of known DCDA or MCDA chorionicity, known pregnancy outcome, last ultrasound scan within 14 days before birth and delivery between 25 and 38 weeks' gestation (Analysis A). An analysis was also conducted excluding pregnancies with complications recorded (Analysis B). Previously published twin EFW reference ranges were used in the analysis. A joint statistical model for EFW and observed birth weight for each pregnancy was created in order to estimate population birth-weight reference ranges corresponding to the distribution expected if all pregnancies delivered at any given gestational age. It was not assumed that the median EFW was equal to birth weight for any given gestational age. The models were fitted using a Bayesian approach.

RESULTS

We retrieved data on 1664 twin pregnancies, of which 707 DCDA and 241 MCDA pregnancies met the inclusion criteria. In Analysis A, the estimated population median birth weight was similar to the median EFW at around 27 weeks' gestation but fell below the EFW values with increasing gestation, being 156 g lower in both DCDA and MCDA pregnancies at 35 weeks; this finding was confirmed by direct comparison of the last EFW and birth-weight values in each pregnancy. When the analysis was repeated after excluding complicated twin pregnancies (Analysis B), compared with Analysis A, there was very little difference in the median birth-weight results obtained across gestation. The largest absolute difference between Analyses A and B for DCDA twins was at 31, 32 and 33 weeks, with a 9-g lower median birth weight in Analysis A compared with Analysis B. The largest absolute difference for MCDA twins was greater than that for DCDA twins, with a 21-g lower median birth weight at 25 weeks in Analysis A compared with Analysis B.

CONCLUSIONS

We have established population chorionicity-specific birth-weight reference charts for DCDA and MCDA twin pregnancies, corresponding to the range expected were all pregnancies to deliver at any given gestational age. In this population of twins, the median birth weight was consistently lower than that reported for singletons, and there was variation in the median birth weight at different gestational ages according to chorionicity. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. - Legal Statement: This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

Two cases of non-parasitic splenic cysts and spleen-preserving therapy

We review two different presentations of non-parasitic splenic cysts, both of which are post-traumatic in aetiology. The first case was of slower onset and was managed electively. The second case was of acute onset and was managed as an emergency. Non-parasitic splenic cysts are uncommon and the optimal management strategy for them is not well defined. Historically, treatment has been with open splenectomy; however, infection rates following this surgery have been high, making it an unattractive management option. Both cases were managed successfully with laparoscopic fenestration with no recurrence at subsequent follow-up.

Non-viral reprogramming of human nucleus pulposus cells with FOXF1 via extracellular vesicle delivery: an in vitro and in vivo study

Intervertebral disc (IVD) degeneration is characterized by decreased cellularity and proteoglycan synthesis and increased inflammation, catabolism, and neural/vascular ingrowth. Regenerative methods for IVD degeneration are largely cell-therapy-based or involve viral vectors, which are associated with mutagenesis and undesired immune responses. The present study used bulk electroporation and engineered extracellular vesicles (EVs) to deliver forkhead-box F1 (FOXF1) mRNA to degenerate human nucleus pulposus (NP) cells as a minimally invasive therapeutic strategy for IVD regeneration. Bulk electroporation was used to investigate FOXF1 effects on human NP cells during a 4-week culture in 3D agarose constructs. Engineered EV delivery of FOXF1 into human IVD cells in monolayer was determined, with subsequent in vivo validation in a pilot mouse IVD puncture model. FOXF1 transfection significantly altered gene expression by upregulating healthy NP markers [FOXF1, keratin 19 (KRT19)], decreasing inflammatory cytokines [interleukin (IL)-1β, -6], catabolic enzymes [metalloproteinase 13 (MMP13)] and nerve growth factor (NGF), with significant increases in glycosaminoglycan accumulation in human NP cells. Engineered EVs loaded with FOXF1 demonstrated successful encapsulation of FOXF1 cargo and effective uptake by human NP cells cultured in monolayer. Injection of FOXF1-loaded EVs into the mouse IVD in vivo resulted in a significant upregulation of FOXF1 and Brachyury, compared to controls at 7 d post-injection, with no evidence of cytotoxicity. This is the first study to demonstrate non-viral delivery of FOXF1 and reprogramming of human NP cells in vitro and mouse IVD cells in vivo. This strategy represents a non-addictive approach for treating IVD degeneration and associated back pain.

Assessing physical activity in people with mental illness: 23-country reliability and validity of the simple physical activity questionnaire (SIMPAQ)

BACKGROUND

Physical inactivity is a key contributor to the global burden of disease and disproportionately impacts the wellbeing of people experiencing mental illness. Increases in physical activity are associated with improvements in symptoms of mental illness and reduction in cardiometabolic risk. Reliable and valid clinical tools that assess physical activity would improve evaluation of intervention studies that aim to increase physical activity and reduce sedentary behaviour in people living with mental illness.

METHODS

The five-item Simple Physical Activity Questionnaire (SIMPAQ) was developed by a multidisciplinary, international working group as a clinical tool to assess physical activity and sedentary behaviour in people living with mental illness. Patients with a DSM or ICD mental illness diagnoses were recruited and completed the SIMPAQ on two occasions, one week apart. Participants wore an Actigraph accelerometer and completed brief cognitive and clinical assessments.

RESULTS

Evidence of SIMPAQ validity was assessed against accelerometer-derived measures of physical activity. Data were obtained from 1010 participants. The SIMPAQ had good test-retest reliability. Correlations for moderate-vigorous physical activity was comparable to studies conducted in general population samples. Evidence of validity for the sedentary behaviour item was poor. An alternative method to calculate sedentary behaviour had stronger evidence of validity. This alternative method is recommended for use in future studies employing the SIMPAQ.

CONCLUSIONS

The SIMPAQ is a brief measure of physical activity and sedentary behaviour that can be reliably and validly administered by health professionals.

Evaluation of the BAX® System for Detection of Salmonella in Selected Foods: Collaborative Study

A multilaboratory study was conducted to compare the automated BAX® System to the standard cultural methods for detection of Salmonella in selected foods. Five food types—frankfurters, raw ground beef, mozzarella cheese, raw frozen tilapia fish, and orange juice—at 3 inoculation levels, were analyzed by each method. A sixth food type, raw ground chicken, was tested using 3 naturally contaminated lots. A total of 16 laboratories representing government and industry participated. In this study, 1386 samples were analyzed, of which 1188 were paired samples and 198 were unpaired samples. Of the 1188 paired samples, 461 were positive by both methods and 404 were negative by both methods. Thirty-seven samples were positive by the BAX System but negative by the standard reference method, and 11 samples were positive by standard cultural method and negative by the BAX System. Of the 198 unpaired samples, 106 were positive by the BAX System and 60 were positive by the standard cultural method. A Chi square analysis of each of the 6 food types, at the 3 inoculation levels tested, was performed. For all foods, the BAX System demonstrated results comparable to those of the standard reference methods based on the Chi square results.

Why has the caesarean rate increased dramatically in Bangladesh?

OBJECTIVE

The objective is to assess the reasoning by families in deciding between a home vs. facility delivery and vaginal vs. caesarean.

STUDY DESIGN

The authors selected a convenience sample of 16 villages in Sathkira district in southwest Bangladesh. Evidence was drawn from detailed in-home post-delivery interviews with all mothers in these villages who delivered in 2015 or 2016.

METHODS

Local family health workers and paramedics used a structured questionnaire that enabled gathering of relevant quantitative and qualitative evidence. Mothers' reasons for selection of delivery location and type were categorized, and regression analysis was conducted to assess significance of variables that proxy supply and demand factors.

RESULTS

Among 492 completed interviews, 48% were home deliveries, 52% facility deliveries; two-thirds of facility deliveries in private clinics. Overall, sample caesarean rate is 39%, public hospital rate 53%, private clinic rate 86%. Over half of reasons for home delivery refer to pregnancy without complication or access to trusted birth attendant. Over half of reasons for facility delivery refer to medical complications allegedly precluding home delivery, or requiring home-to-facility transfer during labour for reasons not clear to the mother. The decision depends on both 'demand' factors originating with the family (proxied by family income, birth order and education levels) and 'supply' factors originating with obstetric care providers (proxied by number of antenatal visits and variation of caesarean rate by village). In a regression controlling for both demand and supply variables, the above proxy variables are all significant.

IMPLICATIONS FOR NURSING AND HEALTH POLICY

Bangladesh has inadequate nursing support for vaginal delivery in either home or facility. Hence, physicians frequently recommend that women deliver in a facility (usually a physician's clinic). Physicians are reluctant to hire adequate nurses to attend vaginal deliveries. Hence, families with some discretionary income are increasingly opting for a caesarean over vaginal delivery. Facility deliveries reduce incidence of obstructed labour fistula, but probably contribute to rising incidence of iatrogenic fistula. Reducing caesarean rates requires a large increase in numbers of nurses and midwives, and acceptance by physicians of a broad scope of practice for nurses/midwives in vaginal deliveries.

Surface EMG signal normalisation and filtering improves sensitivity of equine gait analysis

Low-frequency noise attenuation and normalisation are fundamental signal processing (SP) methods for surface electromyography (sEMG), but are absent, or not consistently applied, in equine biomechanics. The purpose of this study was to examine the effect of different band-pass filtering and normalisation conventions on sensitivity for identifying differences in sEMG amplitude-related measures, calculated from leading (LdH) and trailing hindlimb (TrH) during canter, where between-limb differences in vertical loading are known. sEMG and 3D-kinematic data were collected from the right Biceps Femoris in 10 horses during both canter leads. Peak hip and stifle joint angle and angular velocity were calculated during stance to verify between-limb biomechanical differences. Four SP methods, with and without normalisation and high-pass filtering, were applied to raw sEMG data. Methods 1 (M1) to 4 (M4) included DC-offset removal and full-wave rectification. Method 2 (M2) included additional normalisation relative to maximum sEMG across all strides. Method 3 (M3) included additional high-pass filtering (Butterworth 4th order, 40 Hz cut-off), for artefact attenuation. M4 included the addition of high-pass filtering and normalisation. Integrated EMG (iEMG) and average rectified value (ARV) were calculated using processed sEMG data from M1 – M4, with stride duration as the temporal domain. sEMG parameters, within M1 – M4, and kinematic parameters were grouped by LdH and TrH and compared using repeated measures ANOVA. Significant between-limb differences for hip and stifle joint kinematics were found, indicating functional differences in hindlimb movement. M2 and M4, revealed significantly greater iEMG and ARV for LdH than TrH (P<0.01), with M4 producing the lowest P-values and largest effect sizes. Significant between-limb differences in sEMG parameters were not observed with M1 and M3. The results indicate that equine sEMG SP should include normalisation and high-pass filtering to improve sensitivity for identifying differences in muscle function associated with biomechanical changes during equine gait.

Does equestrian knowledge and experience influence selection and training practices for showjumping horses?

Selection and training methods for showjumping horses are largely anecdotal, and performance analysis has been proposed as a method for scientifically improving competitive outcomes. To employ performance analysis in showjumping, an understanding of the tacit and explicit knowledge and practices of equestrians is required to identify relevant performance indicators. This study aimed to examine the knowledge and practices of equestrians with varying levels of experience (advanced and novice) for selecting horses, based on evaluation of movement, and training showjumping horses using an original questionnaire. It was hypothesised that differences would be present between advanced and novice responses. The questionnaire was composed of closed-end and follow-up open-end questions and 225 equestrians (66.7% advanced, 33.3% novice) participated. Closed-end responses from advanced and novice groups were analysed separately using Chi-Squared tests and open-end responses were subjected to thematic and content analysis. Closed-end responses showed significant within-group preferences (P<0.0001) for specific movement traits and training methods and between-group response differences <13% revealed that advanced and novice groups displayed similar preferences. Thematic analysis indicated different preferences for movement traits when selecting showjumping horses, as well as differences in the level of tacit knowledge between advanced and novice groups. Advanced equestrians placed greater emphasis on aesthetic forelimb traits than novice equestrians, who emphasised traits that they may be less capable of influencing, such as hindlimb impulsion and position of the horse at take-off. An emphasis on hindlimb movement and flatwork/non-jumping exercises for showjumping training was observed across both groups. Understanding equestrian tacit knowledge and its application is fundamental for developing research that is relevant to equestrians. Findings from this study may form a basis for research to identify relevant, objective performance indicators for performance analysis in showjumping, with the ultimate goal of improving competitive performance and welfare for equine athletes.

SAT-262 Differential Metabolic, Thermal, and Pulmonary Responses to Early Life Ozone Exposure in Male and Female Rats

The essential role that early life events (i.e., intrauterine growth restriction) and environmental exposures (i.e., air pollution) play in development of childhood asthma and obesity are only partly understood. Notably, asthmatic children who develop obesity through adolescence have poorer disease outcomes. In our previous studies we showed that exposure of Long-Evans rats to the oxidant air pollutant, ozone (O₃), during implantation [gestational days (GD) 5 and 6; 0.8 ppm x 4h] resulted in growth restriction at GD21. The aims of this study were to determine whether gestational ± repeated peri-adolescent O₃-exposure (0.4-0.8 ppm x 4h; once/week at 5, 6, and 7 weeks-of-age) would alter offspring metabolism, body, or lung growth, and acute thermal or pulmonary responses to O₃. Using 2-way ANOVA with Dunnett’s post hoc correction, responses in males (M) and females (F) were evaluated separately; all O₃-exposed groups were compared to controls [air-exposed dams + PN-Air-(x3)] of the corresponding sex. By postnatal (PN) day 45, results showed that in males, dam O₃-exposure was associated with augmented body “height” (skull base-to-tail head) and increases in serum triglyceride, and cholesterol levels; but not body weight, weight adjusted by height (gm/cm), or corrected lung (fixed) volume (mL/cm height x100%). PN-O₃x3 exposures were associated with increased HOMA-IR ratios and further increases in cholesterol. In females, dam O₃-exposure was associated with lower lung volumes and increased serum cholesterol; while PN-O₃x3 exposure was associated with reduced weight/height (gm/cm). For both sexes, the degree of acute hypothermia was altered in association with both dam- and especially PN-O₃ exposures; whereas lung injury (e.g., increased protein leakage) and inflammation (e.g., neutrophils) in lung lavage fluid, were increased chiefly by PN-O3 exposure. Particularly in males, lesser inflammatory responses were observed in O₃+O₃x3 rats (e.g., reduced KC-GRO and IL-6 cytokine levels) compared to Air+O₃x3 rats. Conversely, lavage fluid TNFα concentrations were increased only in the O₃+O₃x3 males. Taken together, data suggest that O₃ exposure during gestation played a greater role in predisposing offspring to dyslipidemia, whereas peri-adolescent exposure dominated the acute hypothermia and inflammatory responses. Importantly, males exposed to both gestational and postnatal O₃ appeared to (A) develop greater dyslipidemia (a precursor of metabolic syndrome) and (B) altered lung innate inflammatory responses − potentially influencing T_H-1 to T_H-2 balance (a precursor to allergic asthma) later in life. (This abstract does not reflect USEPA policy).

The effect of proprioceptive knee bracing on knee stability after anterior cruciate ligament reconstruction

BACKGROUND

Injury to the anterior cruciate ligament (ACL) is common among young athletes and can impact knee stability and control. Wearing proprioceptive knee braces can improve knee control and may reduce the risk factors associated with injury and re-injury, although the effect of such braces after ACL reconstruction (ACLR) is unclear.

RESEARCH QUESTION

This study aimed to determine the effect of proprioceptive knee bracing on knee control and subjective rating of participants post ACLR during three dynamic tasks.

METHODS

Fifteen participants 2-10 years post ACLR performed a slow step down, single leg drop jump, and pivot turn jump with and without a proprioceptive knee brace. Knee kinematics in the sagittal (flexion - extension), coronal (abduction - adduction), and transverse (internal - external rotation) planes were collected using a 3D infrared system. Paired t-tests were performed to explore differences in knee angles and angular velocities between the no brace and brace conditions during the three tasks. After each task, subjective ratings regarding ease of the task were recorded.

RESULTS

The brace reduced the peak knee external rotation angle and range of motion in the transverse plane during the pivot turn jump task, and significantly increased the maximum knee flexion angular velocity during the single leg drop jump task. The majority of participants reported that tasks were easier to perform with the proprioceptive brace than without.

SIGNIFICANCE

This study confirms that proprioceptive knee braces can significantly influence knee kinematics during dynamic tasks post ACLR. The observed effects were clinically relevant.

The effects of three quarter and full length foot orthoses on knee mechanics in healthy subjects and patellofemoral pain patients when walking and descending stairs

BACKGROUND

An increased load of the patellofemoral joint is often attributed to foot function in patients with patellofemoral pain. Foot orthoses are commonly prescribed for this condition; however the mechanisms by which they work are poorly understood. The aim of this study was to investigate the kinematics and kinetics of the knee between patellofemoral pain patients and a group of healthy subjects when using a standardised foot orthosis prescription during walking and step descent.

METHOD

Fifteen healthy subjects and fifteen patients diagnosed with PFP with a foot posture index greater than 6, had foot orthoses moulded to their feet. They were asked to walk at a self-selected pace and complete a 20 cm step descent using customised orthoses with ¾ and full length wedges. Kinematic and Kinetic data were collected and modelled using Calibrated Anatomical System Technique.

RESULTS

Significant differences were seen in both the kinematics and kinetics between the healthy group and the PFP patients at the knee. A significant reduction in the knee coronal plane moment was found during the forward continuum phase of step descent when wearing the foot orthoses; this was attributed to a change in the ground reaction force as there were no changes reported in the kinematics of the knee with the orthoses.

CONCLUSIONS

This study identified potentially clinically important differences in the knee mechanics between the PFP patients and the healthy group during walking and step descent. The foot orthoses reduced the coronal plane knee moment in the PFP patients to a value similar to that of the healthy subjects with no intervention.

Abstract OT3-06-01: SHERBOC: A double-blind, placebo-controlled, phase 2 trial of seribantumab (MM-121) plus fulvestrant in postmenopausal women with hormone receptor-positive, heregulin positive, HER2 negative metastatic breast cancer whose disease progressed after prior systemic therapy

Background: The receptor tyrosine kinase, HER3 and its ligand, heregulin (HRG), have been implicated in the initiation and progression of multiple cancer types including: breast, lung, and head & neck cancers. Seribantumab is a fully human, monoclonal IgG2 antibody that binds to the ligand-binding domain of HER3 and inhibits HRG-mediated signaling. Previously, seribantumab was tested in combination with exemestane in a placebo-controlled, Phase 2 study in post-menopausal women with ER/PR+, HER2 negative metastatic breast cancer (mBC). Although the trial failed to meet its primary efficacy objective of a 50% reduction in hazard ratio in the seribantumab/exemestane treatment vs. the placebo/exemestane control group, a positive trend in PFS and a statistically significant improvement in median OS was observed in patients in the seribantumab/exemestane treatment group. Seribantumab has also been tested in three randomized Phase 2 studies adding to standard of care (SOC) in non-small cell lung, ER/PR+ mBC, and platinum resistant/refractory ovarian cancer. These studies were retrospectively analyzed to determine correlation between HRG mRNA levels in tumor tissue and PFS. In each of these studies, the presence of tumor cell HRG mRNA was prognostic for shortened PFS with SOC treatment. Further, the addition of seribantumab to SOC therapy improved PFS for patients with HRG+ tumors. These data support the hypothesis that HRG expression may define a drug tolerant cancer cell phenotype characterized by poor response to multiple classes of cytotoxic and targeted therapies, including aromatase inhibitors and SERDs. Additionally, blockade of HRG-induced HER3 signaling by seribantumab may counter such protective effects of HRG on cancer cells, with the potential for improved outcomes in HRG+ patients. It is estimated that ˜45% of hormone-receptor positive, HER2 negative advanced breast cancers are HRG+ and that HRG expression may contribute to accelerated clinical progression observed in this subset of patients.

Trial design: In the upcoming randomized, double-blinded, multi-center, Phase 2 study, ER/PR receptor-positive, HER2 negative mBC patients with HRG+ tumors will be prospectively selected using a HRG RNA in situ hybridization assay. Approximately 200 women will be screened to enroll 80 HRG+ subjects. Eligible subjects will be randomized in a 1:1 ratio to receive seribantumab/fulvestrant or placebo/fulvestrant until investigator-assessed disease progression or unacceptable toxicity, whichever comes first. Subjects will have progressed on one or two prior hormonal therapies, one of which must have been a CDKi-containing regimen. The goal of this study is to determine if the combination of seribantumab + fulvestrant is more effective than placebo + fulvestrant based on PFS (primary end point) in HRG positive subjects. Secondary endpoints include OS, objective response rate, and time to progression. Safety will also be assessed. Enrollment is expected to begin in 2017 at approximately 80 sites globally.

Citation Format: Kaufman PA, Pipas M, Finn GJ, Mathews SE, Zhang H, Richards J, Kudla AJ, Bloom T, Zalutskaya AA, Llorin-Sangalang J, Pinto AC, Ettl J. SHERBOC: A double-blind, placebo-controlled, phase 2 trial of seribantumab (MM-121) plus fulvestrant in postmenopausal women with hormone receptor-positive, heregulin positive, HER2 negative metastatic breast cancer whose disease progressed after prior systemic therapy [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT3-06-01.

Kinematics of the elbow and stifle joints in greyhounds during treadmill trotting An investigation of familiarisation

We studied the familiarisation time required to obtain reliable sagittal plane kinematics for the elbow and stifle joints in eleven treadmill-naïve greyhounds trotting on a treadmill. Motion analysis software was used to measure sagittal elbow and stifle joint movements and to calculate joint angular velocities. After a twominute walking initiation period, the dogs trotted for two and a half minutes. Three trials of three seconds (27 to 30, 72 to 75 and 117 to 120 seconds) trotting, each comprising four complete strides, were analysed. The angle versus time and angular velocity versus time graphs were plotted. For each stride, angular velocity and angular velocity data at key points during the gait cycle were recorded. These angles corresponded with the flexion and extension angles and the peak angular velocities of the elbow and stifle joints during stance and swing phase. Reliable elbow and stifle joint kinematics were obtained within 30 seconds of trotting, which did not differ significantly over the twominute test period indicating that the dogs had familiarised to the treadmill.

Molecular and epidemiological evidence of patient-to-patient hepatitis C virus transmission in a Scottish emergency department

BACKGROUND

Transmission of hepatitis C virus (HCV) in the healthcare setting is rare. Routine infection prevention and control measures mean that this should be a preventable 'never event'.

AIM

To investigate the diagnosis of acute healthcare-associated HCV infection.

METHODS

Epidemiological and molecular investigation of a case of acute HCV infection associated with nosocomial exposure.

FINDINGS

Detailed investigation of the treatment history of a patient with acute HCV infection identified transmission from a co-attending patient in an emergency department as the likely source; this possibility was confirmed by virus sequence analysis. The precise route of transmission was not identified, though both patient and source had minimally invasive healthcare interventions. Review of infection, prevention and control identified potentially contributory factors in the causal pathway including hand hygiene, inappropriate use of personal protective equipment, and blood contamination of the surface of the departmental blood gas analyser.

CONCLUSION

We provide molecular and epidemiological evidence of HCV transmission between patients in an emergency department that was made possible by environmental contamination. Patients with HCV infection are higher users of emergency care than the general population and a significant proportion of those affected remain unknown and/or infectious. Equipment, departmental design, staff behaviour, and patient risk require regular review to minimize the risk of nosocomial HCV transmission.

Torque-angle-velocity Relationships and Muscle Performance of Professional and Youth Soccer Players

Soccer matches consist of a variety of different activities, including repeated sprints. Time to attain velocity (TTAV), load range (LR) and the torque-angle-velocity relationship (TAV_3D) represent an important measurement of muscle performance, however there are few related studies. The aim of this study was to compare these outcomes between soccer players of different age category. 17 professional (PRO) and 17 under-17 (U17) soccer players were assessed for concentric knee flexion/extension at 60, 120 and 300°/s. For the extensor muscles, differences were found in favor of the U17 group for TTAV and LR outcomes at 120°/s, however, the PRO group maintained higher torques in both movement directions in comparison to the U17 in TAV_3D evaluation. These results suggest that muscle performance of the PRO group is more efficient than the U17 group.

Dropout from physical activity interventions in people living with HIV: a systematic review and meta-analysis

Physical activity (PA) interventions have been shown to improve the health of people living with HIV (PLWH), yet treatment dropout poses an important challenge. We conducted a meta-analysis to investigate the prevalence and predictors of treatment dropout in PA interventions in PLWH. Electronic databases were searched for records up to September 2016. Randomized control trials of PA interventions in PLWH reporting dropout rates were included. Random effects meta-analysis and meta-regression analyses were employed. In 36 studies involving 49 PA intervention arms, 1128 PLWH were included (mean age = 41.6 years; 79.3% male; 39% White). The trim and fill adjusted treatment dropout rate was 29.3% (95% CI = 24.5-34.7%). There was a significant lower dropout rate in resistance training interventions compared with aerobic (p = 0.003) PA interventions, in studies utilizing supervised interventions throughout the study period (p < 0.001), and in studies using adequately qualified professionals (p < 0.001). Exerciser/participant variables that moderated higher dropout rates were a lower percentage of male participants (β = 1.15, standard error (SE) = 0.49, z = 2.0, p = 0.048), a lower body mass index(BMI) (β = 0.14, SE = 0.06, z = 2.16, p = 0.03), and a lower cardiorespiratory fitness (β = 0.10, SE = 0.04, z = 2.7, p = 0.006). The dropout from PA interventions is much higher in PLWH than in many other populations with chronic morbidities. Qualified professionals (i.e., exercise physiologists, physical educators, or physical therapists) should be incorporated as key care providers in the multidisciplinary care of HIV/AIDS and should prescribe supervised PA for PLWH in order to enhance adherence and reduce the burden of HIV/AIDS. Special attention should be given men, those with a higher BMI, and those with a lower cardiorespiratory fitness.

Length of stay and cost analysis of neonates undergoing surgery at a tertiary neonatal unit in England

Introduction There is a lack of knowledge on the average length of stay (LOS) in neonatal units after surgical repair of common congenital anomalies. There are few if any publications reporting the activity performed by units undertaking neonatal surgery. Such activity is important for contracting arrangements, commissioning specialist services and counselling parents. The aim of this study was to describe postnatal LOS for infants admitted to a single tertiary referral neonatal unit with congenital malformations requiring surgery. Methods Data on nine conditions were collected prospectively for babies on the neonatal unit over a five-year period (2006-2011). For those transferred back to their local unit following surgery, the local unit was contacted to determine the total LOS. Only those babies who had surgery during their first admission to our unit and who survived to discharge were included in the study. Cost estimates were based on the tariffs agreed for neonatal care between our trust and the London specialised commissioning group in 2011-2012. Results The median LOS for the conditions studied was: gastroschisis 35 days (range: 19-154 days), oesophageal atresia 33 days (range: 9-133 days), congenital diaphragmatic hernia 28 days (range: 7-99 days), intestinal atresia 24 days (range: 6-168 days), Hirschsprung's disease 21 days (range: 15-36 days), sacrococcygeal teratoma 17 days (range: 12-55 days), myelomeningocoele 15.5 days (range: 8-24 days), anorectal malformation 15 days (range: 6-90 days) and exomphalos 12 days (range: 3-228 days). The total neonatal bed day costs for the median LOS ranged from £8,701 (myelomeningocoele) to £23,874 (gastroschisis). The cost of surgery was not included. Conclusions There is wide variation in LOS for the same conditions in a single neonatal unit. This can be explained by different types and severity within the same congenital anomalies, different surgeons and other clinical confounders (eg sepsis, surgical complications, associated anomalies). These data will enable us to give more detailed information to families following prenatal or postnatal diagnosis. They also allow more detailed planning of resource allocation for neonatal admissions.

Health professionals' perspectives on bereavement following loss from a twin pregnancy: a qualitative study

OBJECTIVE

To provide an in-depth understanding of the perspectives of health professionals caring for parents who have lost a baby from a twin pregnancy, either during pregnancy or in the neonatal period.

STUDY DESIGN

A qualitative study involving semi-structured interviews. Twenty-six health professionals were interviewed from maternity and neonatal departments in one hospital. Data were analyzed using a generative thematic approach.

RESULTS

Three main themes were identified from the data: health professionals' lack of confidence in their interactions with bereaved parents; their desire to learn more about bereavement; and a consideration of sensitive health-care practices for bereaved parents.

CONCLUSIONS

Health professionals acknowledged that parents who experience the loss of a twin have specific needs, some of which can be addressed by relatively small changes to clinical practices and behaviors. They felt, however, that they needed education about bereavement in order to react more effectively to bereaved parents' needs.

'I'm OK?' Evaluation of a new walk-in quick-check clinic

Following concerns about asymptomatic people having to wait 2–3 weeks for a standard appointment for screening a new 'I'm OK?' drop-in, nurse-led clinic for the worried well was devised and evaluated after the first 21 weeks (509 patients). Without overt advertising the clinic has run to near capacity and has proved popular, with 98% stating that they would attend such a clinic in the future.

The chlamydia detection rate was 9% in women and 4% in men, with one case of asymptomatic rectal gonorrhoea and two of HIV infection diagnosed allowing early treatment intervention. HIV testing was accepted by 94% of attendees and initial hepatitis B vaccination by 93% of homosexual/bisexual men.

This approach deflects such routine cases, potentially allowing increased time at standard clinic sessions for those with clinical problems staffed by more experienced nurses and doctors. Its success has encouraged us to develop this concept as a cost-effective way of addressing 48-hour genitourinary medicine access.

Effects of minimalist and maximalist footwear on Achilles tendon load in recreational runners

The current investigation aimed to comparatively examine the effects of minimalist, maximalist and conventional footwear on Achilles tendon forces (ATF) during running. Twelve male runners (age 23.11±5.01 years, height 1.78±0.10 cm and body mass 77.13±7.89 kg) ran at 4.0 m/s in the three footwear conditions. ATF’s were calculated using Opensim software allowing the magnitudal and temporal aspects of the ATF to be quantified. Differences between footwear were examined using one-way repeated measures ANOVA. The results showed the peak ATF was significantly larger in minimalist footwear (5.97±1.38 body weight (BW)) compared to maximalist (5.07±1.42 BW). In addition it was revealed that ATF per mile was significantly larger in minimalist (492.31±157.72 BW) in comparison to both maximalist (377.31±148.06 BW) and conventional (402.71±125.51 BW) footwear. Given the relationship between high ATF and Achilles tendon degradation, the current investigation indicated that minimalist footwear may increase runners risk for Achilles tendon injury.