A Psychometric Evaluation of the Interpersonal Hopelessness Scale Among Individuals With Elevated Suicide Risk

The interpersonal theory of suicide hypothesizes that suicide ideation (SI) emerges specifically in the context of hopelessness about the immutability of thwarted belongingness (TB) and perceived burdensomeness (PB; i.e., interpersonal hopelessness). The psychometrics of the Interpersonal Hopelessness Scale (IHS), which could be used to test this hypothesis directly, have not been rigorously evaluated. Participants (U.S. adults reporting past-year SI) completed online self-report assessments at Waves 1 (W1; N = 595) and 2 (W2; N = 215), 1 week apart. Confirmatory factor analyses supported a two-factor structure, IHS-TB and IHS-PB. Correlations indicated strong concurrent validity. Hurdle negative binomial regressions indicated that W1 IHS-TB and IHS-PB scores were associated with SI presence and severity at both waves, but this was inconsistent when adjusting for other W1 variables. IHS-TB and IHS-PB demonstrated excellent internal consistency and moderate to good test-retest reliability. The IHS could improve theory testing and suicide risk assessment and management.

The World Rugby and International Rugby Players Contact Load Guidelines: From conception to implementation and the future

Managing training load in rugby union is crucial for optimising performance and injury prevention. Contact training warrants attention because of higher overall injury and head impact risk, yet players must develop physical, technical, and mental skills to withstand the demands of the game. To help coaches manage contact loads in professional rugby, World Rugby and International Rugby Players convened an expert working group. They conducted a global survey with players to develop contact load guidelines. This commentary aims to describe the contact load guidelines and their implementation, and identify areas where future work is needed to support their evolution.

Child, parent, and family mental health and functioning in Australia during COVID-19: comparison to pre-pandemic data

The COVID-19 pandemic presents significant risks to population mental health. Despite evidence of detrimental effects for adults, there has been limited examination of the impact of COVID-19 on parents and children specifically. We aim to examine patterns of parent and child (0-18 years) mental health, parent substance use, couple conflict, parenting practices, and family functioning during COVID-19, compared to pre-pandemic data, and to identify families most at risk of poor outcomes according to pre-existing demographic and individual factors, and COVID-19 stressors. Participants were Australian mothers (81%) and fathers aged 18 years and over who were parents of a child 0-18 years (N = 2365). Parents completed an online self-report survey during 'stage three' COVID-19 restrictions in April 2020. Data were compared to pre-pandemic data from four Australian population-based cohorts. Compared to pre-pandemic estimates, during the pandemic period parents reported higher rates of parent depression, anxiety, and stress (Cohen's d = 0.26-0.81, all p < 0.001), higher parenting irritability (d = 0.17-0.46, all p < 0.001), lower family positive expressiveness (d = - 0.18, p < 0.001), and higher alcohol consumption (22% vs 12% drinking four or more days per week, p < 0.001). In multivariable analyses, we consistently found that younger parent age, increased financial deprivation, pre-existing parent and child physical and mental health conditions, COVID-19 psychological and environmental stressors, and housing dissatisfaction were associated with worse parent and child functioning and more strained family relationships. Our data suggest wide-ranging, detrimental family impacts associated with the COVID-19 pandemic; and support policy actions to assist families with financial supports, leave entitlements, and social housing.

Association of Maternal Versus Fetal Ehlers-Danlos Syndrome Status with Poor Pregnancy Outcomes

The majority of research papers published on obstetrical outcomes in Ehlers-Danlos syndrome (EDS) have focused on the contribution of maternal EDS to the risk of poor pregnancy outcomes. The purpose of our study was to further clarify the fetal versus maternal contribution of EDS to poor pregnancy outcomes. A web-based, anonymous questionnaire was developed to collect pregnancy histories of families with a member with EDS. The survey was disseminated via social media through the Ehlers Danlos National Foundation. Population descriptors (age, gender, EDS diagnosis, age of diagnosis) and pregnancy descriptors (number of pregnancies, live births, and birth complications) were collected. To identify fetal and maternal contribution of EDS to poor pregnancy outcomes, three groups were compared based on maternal or infant diagnosis (EDS versus non-EDS). The rate of birth complications, treatment for preterm birth, and occurrence of preterm birth, as well as gestational age at preterm birth, were different depending on maternal/ infant EDS status, and these differences were significant when comparing infant EDS status but not when comparing maternal EDS status. The occurrence of PPROM is increased in the non-EDS mother/EDS infant group compared to both EDS mother/non-EDS infant and EDS mother/EDS infant groups (38.9%, 12.5%, 14.8%, p = 0.025). This study identifies that poor outcomes in EDS pregnancies differ depending on the maternal and the fetal EDS status. These insights into maternal and fetal association with certain poor pregnancy outcomes in pregnancies complicated by EDS can further guide physicians in educating, managing, and treating these women during pregnancy.

Perfectionistic Self-Presentation, Socially Prescribed Perfectionism, Self-Oriented Perfectionism, Interpersonal Hopelessness, and Suicidal Ideation in U.S. Adults: Reexamining the Social Disconnection Model

OBJECTIVE

Research has linked perfectionism to increased suicidal ideation (SI), although less is known regarding the mechanisms that explain this relation. The Perfectionism Social Disconnection Model (PSDM) posits that interpersonal aspects of perfectionism cause interpersonal problems (e.g., hostility, loneliness) which in turn increase a person's risk for experiencing SI. The present study aimed to replicate and extend previous findings related to the PSDM and SI using measures of interpersonal hopeless and general hopelessness.

METHOD

Tenets of the PSDM were tested in a sample of 313 U.S. adults with a history of SI, by determining whether experiences of general hopelessness and interpersonal hopelessness explained the relation between three types of perfectionism: perfectionistic self-presentation (PSP), socially prescribed perfectionism (SPP), and self-oriented perfectionism (SOP).

RESULTS

Results indicated that PSP, SPP, and SOP were positively associated with SI, general hopelessness, and interpersonal hopelessness.The relation between aspects of perfectionism and SI demonstrated an indirect effect through interpersonal hopelessness only.

CONCLUSIONS

These results lend support to the PSDM's assertion that interpersonal problems aid in explaining the relation between perfectionism and SI. The current study was limited by the cross-sectional nature of the study as well as the homogenous sample. Implications for research and clinical work are discussed.HIGHLIGHTSAspects of perfectionism are related to suicidal ideationAspects of perfectionism are related to interpersonal hopelessnessInterpersonal hopelessness explains why perfectionism and suicidal ideation are related.

Artificial Intelligence: Guidance for clinical imaging and therapeutic radiography professionals, a summary by the Society of Radiographers AI working group

INTRODUCTION

Artificial intelligence (AI) has started to be increasingly adopted in medical imaging and radiotherapy clinical practice, however research, education and partnerships have not really caught up yet to facilitate a safe and effective transition. The aim of the document is to provide baseline guidance for radiographers working in the field of AI in education, research, clinical practice and stakeholder partnerships. The guideline is intended for use by the multi-professional clinical imaging and radiotherapy teams, including all staff, volunteers, students and learners.

METHODS

The format mirrored similar publications from other SCoR working groups in the past. The recommendations have been subject to a rapid period of peer, professional and patient assessment and review. Feedback was sought from a range of SoR members and advisory groups, as well as from the SoR director of professional policy, as well as from external experts. Amendments were then made in line with feedback received and a final consensus was reached.

RESULTS

AI is an innovative tool radiographers will need to engage with to ensure a safe and efficient clinical service in imaging and radiotherapy. Educational provisions will need to be proportionately adjusted by Higher Education Institutions (HEIs) to offer the necessary knowledge, skills and competences for diagnostic and therapeutic radiographers, to enable them to navigate a future where AI will be central to patient diagnosis and treatment pathways. Radiography-led research in AI should address key clinical challenges and enable radiographers co-design, implement and validate AI solutions. Partnerships are key in ensuring the contribution of radiographers is integrated into healthcare AI ecosystems for the benefit of the patients and service users.

CONCLUSION

Radiography is starting to work towards a future with AI-enabled healthcare. This guidance offers some recommendations for different areas of radiography practice. There is a need to update our educational curricula, rethink our research priorities, forge new strong clinical-academic-industry partnerships to optimise clinical practice. Specific recommendations in relation to clinical practice, education, research and the forging of partnerships with key stakeholders are discussed, with potential impact on policy and practice in all these domains. These recommendations aim to serve as baseline guidance for UK radiographers.

IMPLICATIONS FOR PRACTICE

This review offers the most up-to-date recommendations for clinical practitioners, researchers, academics and service users of clinical imaging and therapeutic radiography services. Radiography practice, education and research must gradually adjust to AI-enabled healthcare systems to ensure gains of AI technologies are maximised and challenges and risks are minimised. This guidance will need to be updated regularly given the fast-changing pace of AI development and innovation.

Health Insurance and Mental Health Care Utilization Among Adults Who Identify as Transgender and Gender Diverse

OBJECTIVE

Transgender people are less likely to have health insurance, which has been associated with reduced utilization of health care. In the current study, the authors sought to assess the role of health insurance in mental health care utilization among transgender individuals.

METHODS

A total of 4,334 adults who self-identified as transgender or gender diverse (neither male nor female) participated in the 2017 Trans Lifeline Mental Health Survey, which included self-report measures of current insurance type and lifetime history of having seen a therapist or psychiatric provider. Logistic regression analyses assessed the association of insurance status with lifetime utilization of a mental health therapist or psychiatric provider.

RESULTS

Although only 8% of the sample were uninsured, these individuals were significantly less likely to have seen a therapist or psychiatric provider in their lifetime compared with those with health insurance, even after the analyses were adjusted for sociodemographic factors. Conversely, those with insurance through the military or the Veterans Health Administration were more than twice as likely as those with employer-provided insurance to have seen a therapist or psychiatric provider. There were no significant differences in mental health care utilization between those with employer-provided insurance versus public or privately purchased insurance.

CONCLUSIONS

Rates of being uninsured were lower than in earlier assessments of transgender adults and adults who identify as gender diverse. However, type of health insurance also appeared to be a notable structural factor contributing to disparities in mental health care utilization among transgender individuals.

Balance and Lower Limb Muscle Activation between In-Line and Traditional Lunge Exercises

In-line and traditional lunge exercises present differences in technique as lower limb positioning (anterioposterior), and medio-lateral (ML) balance may differentially affect primary and stabilizer muscles. The purposes of this study were to examine ML balance and muscle activation in anterior and posterior leg positions between in-line and traditional lunge exercises. Fifteen young, healthy, resistance-trained men (25 ± 5 years) performed 2 different lunge exercises (in-line and traditional) at their 10 repetition maximum in a randomized, counterbalanced fashion. Surface electromyography measured muscle activation of the vastus lateralis, biceps femoris, gluteus maximus, and gluteus medius. ML balance was measured with a Wii Fit Balance Board. The vastus lateralis activity was not significantly different between exercises or leg positions. The biceps femoris activity was not significantly different between exercises, however, it was significantly greater in the anterior compared to the posterior position for the in-line (p = 0.003), and traditional lunge (p < 0.001). The gluteus maximus activity was not significantly different between exercises, however, it was significantly greater in the anterior compared to posterior position for the in-line (p < 0.001) and traditional lunge (p < 0.001). ML balance was significantly greater in the in-line exercise in the anterior limb (p = 0.001). Thus, both in-line and traditional lunge exercises presented similar overall levels of muscle activation, yet the anterior limb generated the highest biceps femoral and gluteus maximus muscle activation when compared to the posterior limb. The in-line lunge presents greater ML balance when compared to the traditional lunge exercise.

Effects of a transition home program on preterm infant emergency room visits within 90 days of discharge

OBJECTIVE

To evaluate effects of a transition home program (THP) and risk factors on emergency room (ER) use within 90 days of discharge for preterm (PT) infants <37 weeks gestation.

STUDY DESIGN

This is a prospective 3-year cohort study of 804 mothers and 954 PT infants. Mothers received enhanced neonatal intensive care unit transition support services until 90 days postdischarge. Regression models were run to identify the effects of THP implementation year and risk factors on ER visits.

RESULTS

Of the 954 infants, 181 (19%) had ER visits and 83/181 (46%) had an admission. In regression analysis, THP year 3 vs year 1 and human milk at discharge were associated with decreased risk of ER visits, whereas increased odds was associated with non-English speaking, maternal mental health disorders and bronchopulmonary dysplasia.

CONCLUSION

Enhanced THP services were associated with a 33% decreased risk of all ER visits by year 3. Social and environmental risk factors contribute to preventable ER visits.

Sport concussion assessment tool-Third edition normative reference values for professional Rugby Union players

OBJECTIVES

To establish normative reference data for the SCAT3 in professional Rugby Union players.

DESIGN

A cross sectional study in professional Rugby Union players competing in national and international professional competitions between 2015 and 2016.

METHODS

The SCAT3 was administered pre-season or prior to tournaments. Data was collected electronically using a custom tablet application. SCAT3 subcomponents distributions were described and normative ranges determined using percentile cut-offs for average, unusually low/high, and extremely low/high scores. The association between player characteristics and performance in SCAT3 subcomponents was also investigated in exploratory analyses.

RESULTS

A total of 3611 professional Rugby Union players were included. The most common baseline symptom was fatigue (14%). The symptom score median (md) was 0 (interquartile range (IQR)=0-1). Symptom severity md was 0 (IQR=0-1). The md of the SAC score was 28 (IQR=26-29). The md of the MBESS was 2 (IQR=0-4). The Tandem gait md was 11.1s (IQR=10.0-12.7s). Upper limb coordination was normal in 98.4%. Younger age and lower educational level were associated with worse performance on delayed recall and reverse month sub-components of the SCAT3 (p<0.0001). No statistically significant differences in SCAT3 subcomponents were evident across gender.

CONCLUSIONS

Representative normative reference values for the SCAT3 among professional Rugby Union players are provided. Baseline performance on concentration and delayed recall tests may be lower in younger athletes or in those with lower educational level.

Brain oxygenation declines in elite Kenyan runners during a maximal interval training session

PURPOSE

The purpose of this study was to characterise the cerebral oxygenation (Cox) response during a high-intensity interval training session in Kenyan runners, and to examine any relationship with running performance.

METHODS

15 Kenyan runners completed a 5-km time trial (TT) and a Fatigue Training Test on a treadmill (repeated running bouts of 1-km at a pace 5% faster than their mean 5-km TT pace with a 30-s recovery until exhaustion). Changes in Cox were monitored via near-infrared spectroscopy through concentration changes in oxy- and deoxy-haemoglobin (Δ[O₂Hb] and Δ[HHb]), tissue oxygenation index (TOI), and total hemoglobin index (nTHI).

RESULTS

The number of 1-km repetitions achieved by the participants was 5.5 ± 1.2 repetitions at a mean pace of 20.5 ± 0.7 km h^-1. Δ[O₂Hb] measured at the end of each running repetition declined progressively over the course of the trial (p = 0.01, ES = 4.59). Δ[HHb] increased during each running bout until the end of the Fatigue Training Test (p < 0.001; ES = 6.0). TOI decreased significantly from the beginning of the test (p = 0.013, ES = 1.83), whereas nTHI remained stable (ES = 0.08). The Cox decline in the Fatigue Training Test was negatively correlated with the speed at which the test was completed (p = 0.017; r = -0.61), suggesting that the best performers were able to defend their Cox better than those of lower running ability.

CONCLUSIONS

In conclusion, this study suggests that elite Kenyan runners cannot defend cerebral oxygenation when forced to exercise to their physiological limits. This emphasises the critical importance of pacing in their racing success.

Visual Stimulus Deprivation and Manipulation of Auditory Timing Signals on Pacing Strategy

In this study the effect of complete visual stimulus deprivation and manipulation of auditory timing signals during this deprivation on pacing strategy during an exercise bout were examined. 7 moderately trained men completed four 40-km cycling time trials under laboratory conditions in either normal light or absolute darkness, with either correct or manipulated auditory timing signals and without any other timing cues. The subjects were told to perform the time trial in the fastest time possible. There was no significant difference among trials for time to perform the trial, power output, heart rate, or ratings of perceived exertion, indicating that brain-control mechanisms responsible for pacing are not affected by manipulation of light or auditory signals.

Technical innovation changes standard radiographic protocols in veterinary medicine: is it necessary to obtain two dorsoproximal-palmarodistal oblique views of the equine foot when using computerised radiography systems?

Since the 1950s, veterinary practitioners have included two separate dorsoproximal-palmarodistal oblique (DPr-PaDiO) radiographs as part of a standard series of the equine foot. One image is obtained to visualise the distal phalanx and the other to visualise the navicular bone. However, rapid development of computed radiography and digital radiography and their post-processing capabilities could mean that this practice is no longer required. The aim of this study was to determine differences in perceived image quality between DPr-PaDiO radiographs that were acquired with a computerised radiography system with exposures, centring and collimation recommended for the navicular bone versus images acquired for the distal phalanx but were subsequently manipulated post-acquisition to highlight the navicular bone. Thirty images were presented to four clinicians for quality assessment and graded using a 1-3 scale (1=textbook quality, 2=diagnostic quality, 3=non-diagnostic image). No significant difference in diagnostic quality was found between the original navicular bone images and the manipulated distal phalanx images. This finding suggests that a single DPr-PaDiO image of the distal phalanx is sufficient for an equine foot radiographic series, with appropriate post-processing and manipulation. This change in protocol will result in reduced radiographic study time and decreased patient/personnel radiation exposure.

Are gait characteristics and ground reaction forces related to energy cost of running in elite Kenyan runners?

The aim of this study was to determine whether gait cycle characteristics are associated with running economy in elite Kenyan runners. Fifteen elite Kenyan male runners completed two constant-speed running sets on a treadmill (12 km ·h^-1 and 20 km ·h^-1). VO₂ and respiratory exchange ratio values were measured to calculate steady-state oxygen and energy cost of running. Gait cycle characteristics and ground contact forces were measured at each speed. Oxygen cost of running at different velocities was 192.2 ± 14.7 ml· kg^-1· km^-1 at 12 km· h^-1 and 184.8 ± 9.9 ml· kg^-1· km^-1 at 20 km· h^-1, which corresponded to a caloric cost of running of 0.94 ± 0.07 kcal ·kg^-1·km^-1 and 0.93 ± 0.07 kcal· kg^-1· km^-1. We found no significant correlations between oxygen and energy cost of running and biomechanical variables and ground reaction forces at either 12 or 20 km· h^-1. However, ground contact times were ~10.0% shorter (very large effect) than in previously published literature in elite runners at similar speeds, alongside an 8.9% lower oxygen cost (very large effect). These results provide evidence to hypothesise that the short ground contact times may contribute to the exceptional running economy of Kenyan runners.

Paralympic athletes with cerebral palsy display altered pacing strategies in distance-deceived shuttle running trials

This study investigated performance and physiology to understand pacing strategies in elite Paralympic athletes with cerebral palsy (CP). Six Paralympic athletes with CP and 13 able-bodied (AB) athletes performed two trials of eight sets of 10 shuttles (total 1600m). One trial was distance-deceived (DEC, 1000 m + 600 m) one trial was nondeceived (N-DEC, 1600 m). Time (s), heart rate (HR, bpm), ratings of perceived exertion (RPE, units), and electromyography of five bilateral muscles (EMG) were recorded for each set of both trials. The CP group ran slower than the AB group, and pacing differences were seen in the CP DEC trial, presenting as a flat pacing profile over the trial (P < 0.05). HR was higher and RPE was lower in the CP group in both trials (P < 0.05). EMG showed small differences between groups, sides, and trials. The present study provides evidence for a possible pacing strategy underlying exercise performance and fatigue in CP. The results of this study show (1) underperformance of the CP group, and (2) altered pacing strategy utilization in the CP group. We proposed that even at high levels of performance, the residual effects of CP may negatively affect performance through selection of conservative pacing strategies during exercise.

Radiographic, computed tomographic and surgical anatomy of the equine sphenopalatine sinus in normal and diseased horses

REASONS FOR PERFORMING STUDY

Knowledge of imaging anatomy, surgical anatomy and disorders affecting the sphenopalatine sinus are currently lacking.

OBJECTIVES

To describe the computed tomographic (CT) and surgical anatomy of the sphenopalatine sinus and diagnosis, treatment and outcome in clinical cases with sphenopalatine sinus disease.

STUDY DESIGN

Cadaver observational study and retrospective case series.

METHODS

The sphenopalatine sinuses of 10 normal cadaver heads were examined with digital radiography, CT and sinoscopic examination prior to anatomical sectioning. Sphenopalatine sinus anatomy was described and compared between cadaver specimens across the imaging modalities. Medical records (January 2004-2014) of cases diagnosed with sphenopalatine sinus disease were reviewed.

RESULTS

The anatomy of the sphenopalatine sinus was variable. The borders of the sphenopalatine sinus were not identifiable on plain radiographs, whereas CT provided useful anatomical information. The palatine portion of the sphenopalatine sinus was consistently accessible sinoscopically and the sphenoidal portion was accessible in 6/10 cadaver heads. Fourteen cases of sphenopalatine sinus disease were identified, presenting with one or more clinical signs of exophthalmos, blindness, unilateral epistaxis or unilateral nasal discharge. Diagnoses included neoplasia (7), progressive ethmoidal haematoma (4), sinus cyst (2) and empyema (1). Computed tomography provided diagnostic information but could not differentiate the nature of soft tissue masses. Standing sinoscopic access to the palatine portion of the sphenopalatine sinus was possible for evaluation, biopsy and resection of abnormal soft tissues. Surgical access to the sphenoidal portion was limited. Eight horses were alive at 1 year after diagnosis, with a worse outcome associated with CT evidence of bone loss and a diagnosis of neoplasia.

CONCLUSIONS

Sphenopalatine sinus disease should be considered a rare cause of the clinical signs described. Knowledge of the anatomical variation of the sphenopalatine sinus is vital for interpreting CT images. A combination of CT and sinoscopy provides the most comprehensive approach for diagnosis and treatment of sphenopalatine sinus disease.

Clinical Research Abstracts of the British Equine Veterinary Association Congress 2015

REASONS FOR PERFORMING STUDY

Injury to the superficial digital flexor tendon (SDFT) is common in equids, with a high risk of re-injury associated with changes in tendon stiffness. In vivo measurement of limb stiffness has been shown to correlate with tendon stiffness after injury [1] but requires kinematic analysis which is impractical in a clinical setting. We have developed a simple system for measuring limb stiffness statically, which could be used as a tool for monitoring SDFT healing.

OBJECTIVES

To validate a goniometric measurement of limb stiffness.

STUDY DESIGN

Cross sectional study.

METHODS

Initially, forelimb stiffness indices were determined at the walk for 6 equids using a validated kinematic analysis [1]. Limb stiffness indices were then calculated using portable floor scales to record ground reaction force (GRF), and an electrogoniometer to record metacarpophalangeal joint angle. Goniometric limb stiffness indices were subsequently measured in 11 horses ranging from 2 to 20 years of age, with no clinical evidence of SDFT injury. Strength and significance of correlation and agreement between the measurement methods was assessed and association between limb stiffness, limb (left vs. right), weight and age of horse and were calculated.

RESULTS

There were strong positive correlations between GRF and joint angle (R(2) = 0.98) and between the static and kinematic methods (R = 0.78, P<0.01). There was a positive correlation between limb stiffness and weight (R(2) = 0.85, P<0.01), but no association with age or limb.

CONCLUSIONS

This study validated the measurement of limb stiffness in a clinical setting. The positive correlation of limb stiffness and weight supports the theory of an optimised limb spring [2] for energy-efficient cursorial locomotion which may, in turn, provide a clinically-relevant measure of running efficiency and therefore the quality of tendon healing post injury. Ethical animal research: Owner consent was obtained.

SOURCE OF FUNDING

None. Competing interests: None declared.

Effect on Oxygen Cost of Transport from 8-Weeks of Progressive Training with Barefoot Running

Popular interest in barefoot running has emerged as a result of its alleged performance and injury prevention benefits. Oxygen cost of transport (COT) improvements from barefoot running, however, remains equivocal. The aim of this study was to determine the influence of an 8-week progressive barefoot training program on COT and associated spatiotemporal variables. 15 male runners participated in this study. Variables such as oxygen uptake, biomechanical and spatiotemporal characteristics of gait, including ground contact (GC) and swing time; stride length and frequency and ankle plantar-dorsiflexion were measured pre- and post-intervention. The COT did not differ between barefoot and shod running either pre- or post-training. Improved barefoot COT (p<0.05) but not shod was found between pre- and post-training. Biomechanical differences between barefoot and shod conditions persisted over the training period. A decrease in barefoot COT was associated with a decrease in GC time (p=0.003, r=0.688) and a small increase in stride frequency (p=0.030; r=0.569). Ground contact time and stride frequency, previously associated with COT, only partly contribute (32% - Stride frequency and 47% - GC time) to a decrease in COT after barefoot training. Thus other physiological and biomechanical variables must influence the improvement in COT after a barefoot training intervention.

Maintained cerebral oxygenation during maximal self-paced exercise in elite Kenyan runners

The purpose of this study was to analyze the cerebral oxygenation response to maximal self-paced and incremental exercise in elite Kenyan runners from the Kalenjin tribe. On two separate occasions, 15 elite Kenyan distance runners completed a 5-km time trial (TT) and a peak treadmill speed test (PTS). Changes in cerebral oxygenation were monitored via near-infrared spectroscopy through concentration changes in oxy- and deoxyhemoglobin (Δ[O2Hb] and Δ[HHb]), tissue oxygenation index (TOI), and total hemoglobin index (nTHI). During the 5-km TT (15.2 ± 0.2 min), cerebral oxygenation increased over the first half (increased Δ[O2Hb] and Δ[HHb]) and, thereafter, Δ[O2Hb] remained constant (effect size, ES = 0.33, small effect), whereas Δ[HHb] increased until the end of the trial ( P < 0.05, ES = 3.13, large effect). In contrast, during the PTS, from the speed corresponding to the second ventilatory threshold, Δ[O2Hb] decreased ( P < 0.05, ES = 1.51, large effect), whereas Δ[HHb] continued to increase progressively until exhaustion ( P < 0.05, ES = 1.22, large effect). Last, the TOI was higher during the PTS than during the 5-km TT ( P < 0.001, ES = 3.08; very large effect), whereas nTHI values were lower ( P < 0.001, ES = 2.36, large effect). This study shows that Kenyan runners from the Kalenjin tribe are able to maintain their cerebral oxygenation within a stable range during a self-paced maximal 5-km time trial, but not during an incremental maximal test. This may contribute to their long-distance running success.

Expressed Breast Milk as a Predictor of Neonatal Yeast Colonization in an Intensive Care Setting

BACKGROUND

Yeast colonization is a predictor for invasive infection in neonates. Candida albicans and Candida parapsilosis are leading causes of invasive fungal infection (IFI) in this population. This study examines maternal breast milk as a predictor of colonization of infants with yeast.

METHODS

Inclusion criteria were admission longer than 72 hours to the neonatal intensive care unit and parental consent. Cultures of expressed breast milk, when available, and swabs from oral, rectal, and inguinal sites were obtained weekly for 12 weeks, or until discharge, transfer, or death. Cultures were analyzed using standard laboratory methods. Clinical information was extracted from medical records.

RESULTS

One hundred thirty infants were enrolled from February 2011 to November 2012. Cultures were obtained in 129 patients. The median (interquartile range [IQR]) gestational age was 34.4 weeks (33.1-37.1 weeks). The median (IQR) birth weight was 2157.5 g (1740-3060 g). No infants developed IFIs. Twenty-nine (22%) infants were colonized with yeast. Potential correlates for colonization in univariate analysis included exposure to antenatal steroids, postnatal antibiotics, and receipt of breast milk containing yeast. Potential correlates that remained after multivariable logistic regression included exposure to antenatal steroids and receipt of breast milk containing yeast. In cases in which yeast was recovered from an individual infant and from the breast milk received by that infant, there was only 30% concordance between yeast species.

DISCUSSION

Recovery of yeast from breast milk is associated with colonization with yeast in the neonate. Because Candida transmission via breast milk had a 30% concordance, breast milk is only one of several ways colonization occurs. Further study is needed on mechanisms of colonization.

Greater performance impairment of black runners than white runners when running in hypoxia

This study aimed to compare the response of performance-matched black and white runners during maximal and sub-maximal running in normoxic and hypoxic conditions. 14 well-trained runners (8 black, 6 white) performed 2 incremental maximal exercise tests and 2 fatigue resistance tests at 21% O2 (normoxia) or 14% O2 (hypoxia). Respiratory parameters, heart rate (HR), lactate concentration ([La(-)]) as well as arterial saturation (SpO2) were measured. Enzyme activities and myosin heavy chain content (MHC) were also measured. White runners reached a significantly greater peak treadmill speed and a higher HRmax than black runners in hypoxia (p<0.05). Additionally, White runners achieved a greater time to fatigue than black runners (p<0.05), with black runners displaying a greater decline in performance in hypoxia compared to normoxia (20.3% vs. 13.4%, black vs. white, respectively). However, black runners presented lower [La(-)] and higher SpO2 than white runners in hypoxia (p<0.05). Black runners had a higher proportion of MHC IIa and higher lactate dehydrogenase activity (p<0.05). The greater performance impairment observed in black runners in hypoxia suggests a greater performance sensitivity to this condition, despite the maintenance of physiological variables such as SpO2 and [La (-) ] within a smaller range than white runners.

Deep digital flexor tendon injury within the hoof capsule; does lesion type or location predict prognosis?

The type and location of deep digital flexor tendon (DDFT) lesions may be important in predicting outcome. The objectives of this study were to determine the frequency of different types of DDFT lesions within the hoof capsule and to determine whether lesion type predicts return to athletic activity. Lesions of the DDFT were divided into: core lesions, dorsal border lesions and parasagittal splits. Lesion location was documented, and follow-up information was obtained by telephone survey at least 18 months after diagnosis. Of 168 horses with primary DDFT injury, 54 horses had dorsal border lesions, 59 had parasagittal splits and 55 had core lesions. Twenty-five per cent of all horses returned to previous levels of athletic activity within 18 months of MRI evaluation. Horses with complete splits or core lesions of the DDFT were significantly less likely to return to some level of athletic activity than horses with dorsal border lesions P<0.001. Dorsal border lesions of the DDFT appear to have a better prognosis than core lesions or parasagittal splits. This study provides additional information that may help clinicians predict the prognosis for different types of DDFT injury.

Detecting genes for variation in parasite burden and immunological traits in a wild population: testing the candidate gene approach

Identifying the genes underlying phenotypic variation in natural populations can provide novel insight into the evolutionary process. The candidate gene approach has been applied to studies of a number of traits in various species, in an attempt to elucidate their genetic basis. Here, we test the application of the candidate gene approach to identify the loci involved in variation in gastrointestinal parasite burden, a complex trait likely to be controlled by many loci, in a wild population of Soay sheep. A comprehensive literature review, Gene Ontology databases, and comparative genomics resources between cattle and sheep were used to generate a list of candidate genes. In a pilot study, these candidates, along with 50 random genes, were then sequenced in two pools of Soay sheep; one with low gastrointestinal nematode burden and the other high, using a NimbleGen sequence capture experiment. Further candidates were identified from single nucleotide polymorphisms (SNPs) that were highly differentiated between high- and low-resistance sheep breeds. A panel of 192 candidate and control SNPs were then typed in 960 individual Soay sheep to examine whether they individually explained variation in parasite burden, as measured as faecal egg count, as well as two immune measures (Teladorsagia circumcincta-specific antibodies and antinuclear antibodies). The cumulative effect of the candidate and control SNPs were estimated by fitting genetic relationship matrices (GRMs) as random effects in animal models of the three traits. No more significant SNPs were identified in the pilot sequencing experiment and association study than expected by chance. Furthermore, no significant difference was found between the proportions of candidate or control SNPs that were found to be significantly associated with parasite burden/immune measures. No significant effect of the candidate or control gene GRMs was found. There is thus little support for the candidate gene approach to the identification of loci explaining variation in parasitological and immunological traits in this population. However, a number of SNPs explained significant variation in multiple traits and significant correlations were found between the proportions of variance explained by individual SNPs across multiple traits. The significant SNPs identified in this study may still, therefore, merit further investigation.

Rates of assay success and genotyping error when single nucleotide polymorphism genotyping in non-model organisms: a case study in the Antarctic fur seal

Although single nucleotide polymorphisms (SNPs) are increasingly being recognized as powerful molecular markers, their application to non-model organisms can bring significant challenges. Among these are imperfect conversion rates of assays designed from in silico resources and the enhanced potential for genotyping error relative to pre-validated, highly optimized human SNPs. To explore these issues, we used Illumina's GoldenGate assay to genotype 480 Antarctic fur seal (Arctocephalus gazella) individuals at 144 putative SNPs derived from a 454 transcriptome assembly. One hundred and thirty-five polymorphic SNPs (93.8%) were automatically validated by the program GenomeStudio, and the initial genotyping error rate, estimated from nine replicate samples, was 0.004 per reaction. However, an almost tenfold further reduction in the error rate was achieved by excluding 31 loci (21.5%) that exhibited unclear clustering patterns, manually editing clusters to allow rescoring of ambiguous or incorrect genotypes, and excluding 18 samples (3.8%) with unreliable genotypes. After stringent quality filtering, we also found a counter-intuitive negative relationship between in silico minor allele frequency and the conversion rate, suggesting that some of our assays may have been designed from paralogous loci. Nevertheless, we obtained over 45 000 individual SNP genotypes with a final error rate of 0.0005, indicating that the GoldenGate assay is eminently capable of generating large, high-quality data sets for non-model organisms. This has positive implications for future studies of the evolutionary, behavioural and conservation genetics of natural populations.

Blood urea nitrogen and serum bicarbonate in extremely low birth weight infants receiving higher protein intake in the first week after birth

OBJECTIVE

To determine correlation between early protein administration and serum blood urea nitrogen (BUN) or bicarbonate (HCO(3)(-)) in extremely low birth weight (ELBW) infants during the first week of life.

STUDY DESIGN

A retrospective review of 154 ELBWs was conducted. Laboratory and nutritional data from postnatal days 1, 4 and 7 were collected. Repeated measures models estimated the relationship of protein intake with BUN and HCO(3)(-) in the first week of life.

RESULT

In total, 359 separate BUN and HCO(3)(-) values were analyzed. Each gram per kilogram of protein administered was associated with an increase in mean BUN of 3.3 mg/dl. This effect decreased daily by 2.1 mg/dl. Each gram per kilogram of protein administered was associated with a decrease in mean HCO(3)(-) by 0.9 mmol/l.

CONCLUSION

The association between protein load and BUN is positive but decreasing over time. Protein is associated with a clinically insignificant decrease in HCO(3)(-). Concerns regarding metabolic derangement from early protein administration in ELBWs are unwarranted.

The science and management of sex verification in sport

The verification of gender eligibility in sporting competition posesa biological and management challenge for sports science and medicine, as well as for sporting authorities. It has been established that in most sporting events, the strength and power advantage possessed by males as a result of the virilising action of hormones such as testosterone produce significant advantages in performance. For this reason, males and females compete largely in separate gender categories. Controversies arise as aresult of intersex conditions, where the classification of individuals into male or female is complex. The present review provides the historical context to the debate, identifying the origins of gender verification as a means to deter cheating. It describes how various testing methods have been attempted, including physical examinations of genitalia, molecular techniques including genetic screening, and complex multidisciplinary approaches including endocrinological, genetic and gynaecological examination. To date, none appear to have provided a satisfactory resolution to the problem, and appear instead to have unfairly discriminated against individuals as a result of inappropriate application of testing results. Sporting authorities have formulated position standsfor the management of such cases, but there is not absolute agreement between them and little evidence to support whether intersex individuals should or should not be allowed to compete in female categories.

The physiological regulation of pacing strategy during exercise: a critical review

The regulation of the pacing strategy remains poorly understood, because much of classic physiology has focused on the factors that ultimately limit, rather than regulate, exercise performance. When exercise is self-paced and work rate is free to vary in response to external and internal physiological cues, then a complex system is proposed to be responsible for alterations in exercise intensity, possibly through altered activation of skeletal muscle motor units. The present review evaluates the evidence for such a complex system by investigating studies in which interventions such as elevated temperature, altered oxygen content of the air, reduced fuel availability and misinformation about distance covered have resulted in alterations to the pacing strategy. The review further investigates how such a pacing strategy might be regulated for optimal performance, while ensuring that irreversible physiological damage is not incurred.

Chemical contaminants in feedlot wastes: concentrations, effects and attenuation

Commercial feedlots for beef cattle finishing are potential sources of a range of trace chemicals which have human health or environmental significance. To ensure adequate protection of human and environmental health from exposure to these chemicals, the application of effective manure and effluent management practices is warranted. The Australian meat and livestock industry has adopted a proactive approach to the identification of best management practices. Accordingly, this review was undertaken to identify key chemical species that may require consideration in the development of guidelines for feedlot manure and effluent management practices in Australia. Important classes of trace chemicals identified include steroidal hormones, antibiotics, ectoparasiticides, mycotoxins, heavy metals and dioxins. These are described in terms of their likely sources, expected concentrations and public health or environmental significance based on international data and research. Androgenic hormones such as testosterone and trenbolone are significantly active in feedlot wastes, but they are poorly understood in terms of fate and environmental implications. The careful management of residues of antibiotics including virginiamycin, tylosin and oxytetracycline appears prudent in terms of minimising the risk of potential public health impacts from resistant strains of bacteria. Good management of ectoparasiticides including synthetic pyrethroids, macrocyclic lactones, fluazuron, and amitraz is important for the prevention of potential ecological implications, particularly towards dung beetles. Very few of these individual chemical contaminants have been thoroughly investigated in terms of concentrations, effects and attenuation in Australian feedlot wastes.

Fluid regimens in the first week of life may increase risk of patent ductus arteriosus in extremely low birth weight infants

BACKGROUND

High fluid volumes may increase neonatal morbidity. However, evidence supporting fluid restriction is inconclusive and restricting fluids may restrict caloric intake.

OBJECTIVE

To determine if higher fluid intake was associated with increased risk of patent ductus arteriosus (PDA) or bronchopulmonary dysplasia (BPD) in extremely low birth weight (ELBW) infants.

STUDY DESIGN

A total of 204 ELBW (<or=32 weeks, <or=1250 g) infant survivors were grouped into low-, intermediate- and high-fluid groups. chi2 analyzed proportions of subjects with and without morbidities across groups. Logistic regression quantified increased risk of PDA or BPD associated with fluid intake while controlling for confounders. Analysis of variance compared differences in caloric intake across groups.

RESULT

After controlling for gestational age, severity of illness and weight change, fluid intake on day 2 (odds ratio (OR) 1.014; confidence interval (CI) 1.001 to 1.028) and day 3 (OR 1.022; CI 1.004 to 1.040) was associated with increased risk of PDA.

CONCLUSION

High fluid intake (>170 ml kg(-1) day(-1)) in the first days of life is associated with increased risk of PDA.