[Acute abdomen-Rare cause in an 80-year-old female patient under immunosuppressive treatment]

An 80-year-old woman presented to the emergency department due to abdominal pain. She had a history of opportunistic pneumonia under the effects of immunosuppression after the diagnosis of autoimmune hepatitis. The imaging showed an omental cake formation and the suspicion of peritoneal carcinomatosis. The patient developed an acute abdomen during the hospital stay, followed by exploratory laparotomy. In the presence of extensive intra-abdominal abscess formation both surgically acquired material and blood culture revealed disseminated nocardiosis. The course was fatal due to fulminant septic shock.

Use of levetiracetam for the successful treatment of suspected myoclonic seizures: five dogs (2016-2022)

OBJECTIVES

Myoclonic seizures are considered a type of generalised seizure characterised by brief, jerking movements of the body. The aim of this study is to describe cases of suspected canine myoclonic seizure of idiopathic aetiology and to discuss the successful use of the anticonvulsant levetiracetam as treatment in each of these cases.

MATERIALS AND METHODS

Dogs with epileptic myoclonus suspected to be idiopathic in aetiology were considered for inclusion. Medical records were reviewed for physical and neurologic examination findings, clinicopathologic results, and diagnostic imaging results. All included dogs were treated with levetiracetam, and their response was reported.

RESULTS

Five dogs were included, all of which had suspected myoclonic seizures either observed in-person or on video recording by a board-certified veterinary neurologist. The duration of myoclonic seizures preceding treatment ranged from one day to one year. One dog also experienced a generalised tonic-clonic seizure. All dogs were treated with levetiracetam. Two dogs experienced long-term myoclonic seizure freedom (duration seizure-free of at least 1 year), and two dogs experienced marked decreased myoclonic seizure frequency. One dog experienced immediate abatement of myoclonic seizures, although levetiracetam was only utilised for 1 month following onset of myoclonic seizures in this patient.

CLINICAL SIGNIFICANCE

Myoclonic seizures can be idiopathic in aetiology. Levetiracetam can be used effectively to rapidly stop myoclonic seizures and to decrease the frequency of myoclonic seizures.

Prospective Longitudinal Assessment of Quality of Life After Stereotactic Ablative Radiotherapy for Oligometastases: Analysis of the Population-based SABR-5 Phase II Trial

AIMS

To evaluate longitudinal patient-reported quality of life (QoL) in patients treated with stereotactic ablative radiotherapy (SABR) for oligometastases.

MATERIALS AND METHODS

The SABR-5 trial was a population-based single-arm phase II study of SABR to up to five sites of oligometastases, conducted in six regional cancer centres in British Columbia, Canada from 2016 to 2020. Prospective QoL was measured using treatment site-specific QoL questionnaires at pre-treatment baseline and at 3, 6, 9, 12, 15, 18, 21, 24, 30 and 36 months after treatment. Patients with bone metastases were assessed with the Brief Pain Inventory (BPI). Patients with liver, adrenal and abdominopelvic lymph node metastases were assessed with the Functional Assessment of Chronic Illness Therapy-Abdominal Discomfort (FACIT-AD). Patients with lung and intrathoracic lymph node metastases were assessed with the Prospective Outcomes and Support Initiative (POSI) lung questionnaire. The two one-sided test procedure was used to assess equivalence between the worst QoL score and the baseline score of individual patients. The mean QoL at all time points was used to determine the trajectory of QoL response after SABR. The proportion of patients with 'stable', 'improved' or 'worsened' QoL was determined for all time points based on standard minimal clinically important differences (MCID; BPI worst pain = 2, BPI functional interference score [FIS] = 0.5, FACIT-AD Trial Outcome Index [TOI] = 8, POSI = 3).

RESULTS

All enrolled patients with baseline QoL assessment and at least one follow-up assessment were analysed (n = 133). On equivalence testing, the patients' worst QoL scores were clinically different from baseline scores and met MCID (BPI worst pain mean difference: 1.8, 90% confidence interval 1.19 to 2.42]; BPI FIS mean difference: 1.68, 90% confidence interval 1.15 to 2.21; FACIT-AD TOI mean difference: -8.76, 90% confidence interval -11.29 to -6.24; POSI mean difference: -4.61, 90% confidence interval -6.09 to -3.14). However, the mean FIS transiently worsened at 9, 18 and 21 months but eventually returned to stable levels. The mean FACIT and POSI scores also worsened at 36 months, albeit with a limited number of responses (n = 4 and 8, respectively). Most patients reported stable QoL at all time points (range: BPI worst pain 71-82%, BPI FIS 45-78%, FACIT-AD TOI 50-100%, POSI 25-73%). Clinically significant stability, worsening and improvement were seen in 70%/13%/18% of patients at 3 months, 53%/28%/19% at 18 months and 63%/25%/13% at 36 months.

CONCLUSIONS

Transient decreases in QoL that met MCID were seen between patients' worst QoL scores and baseline scores. However, most patients experienced stable QoL relative to pre-treatment levels on long-term follow-up. Further studies are needed to characterise patients at greatest risk for decreased QoL.

Predictors of Quality of Life Decline in Patients with Oligometastases treated with Stereotactic Ablative Radiotherapy: Analysis of the Population-Based SABR-5 Phase II Trial

AIMS

Most patients experience stable quality of life (QoL) after stereotactic ablative radiotherapy (SABR) treatment for oligometastases. However, a subset of patients experience clinically relevant declines in QoL on post-treatment follow-up. This study aimed to identify risk factors for QoL decline.

MATERIALS AND METHODS

The SABR-5 trial was a population-based single-arm phase II study of SABR to up to five sites of oligometastases. Prospective QoL was measured using treatment site-specific tools at pre-treatment baseline and 3, 6, 9, 12, 15, 18, 21, 24, 30 and 36 months after treatment. The time to persistent QoL decline was calculated as the time from SABR to the first decline in QoL score meeting minimum clinically important difference with no improvement to baseline score on subsequent assessments. Univariable and multivariable logistic regression analyses were carried out to determine factors associated with QoL decline.

RESULTS

One hundred and thirty-three patients were included with a median follow-up of 32 months (interquartile range 25-43). Thirty-five patients (26%) experienced a persistent decline in QoL. The median time until persistent QoL decline was not reached. The cumulative incidence of QoL decline at 2 and 3 years were 22% (95% confidence interval 14.0-29.6) and 40% (95% confidence interval 28.0-51.2), respectively. In multivariable analysis, disease progression (odds ratio 5.23, 95% confidence interval 1.59-17.47, P = 0.007) and adrenal metastases (odds ratio 9.70, 95% confidence interval 1.41-66.93, P = 0.021) were associated with a higher risk of QoL decline. Grade 3 or higher (odds ratio 3.88, 95% confidence interval 0.92-16.31, P = 0.064) and grade 2 or higher SABR-associated toxicity (odds ratio 2.24, 95% confidence interval 0.85-5.91, P = 0.10) were associated with an increased risk of QoL decline but did not reach statistical significance.

CONCLUSIONS

Disease progression and adrenal lesion site were associated with persistent QoL decline following SABR. The development of grade 3 or higher toxicities was also associated with an increased risk, albeit not statistically significant. Further studies are needed, focusing on the QoL impact of metastasis-directed therapies.

Sprague Dawley rats from different vendors vary in the modulation of prepulse inhibition of startle (PPI) by dopamine, acetylcholine, and glutamate drugs

RATIONALE

Rodent vendors are often utilized interchangeably, assuming that the phenotype of a given strain remains standardized between colonies. Several studies, however, have found significant behavioral and physiological differences between Sprague Dawley (SD) rats from separate vendors. Prepulse inhibition of startle (PPI), a form of sensorimotor gating in which a low-intensity leading stimulus reduces the startle response to a subsequent stimulus, may also vary by vendor. Differences in PPI between rat strains are well known, but divergence between colonies within the SD strain lacks thorough examination.

OBJECTIVES

We explored intrastrain variation in PPI by testing SD rats from two vendors: Envigo and Charles River (CR).

METHODS

We selected drugs acting on four major neurotransmitter systems that have been repeatedly shown to modulate PPI: dopamine (apomorphine; 0.5, 1.5, 3.0 mg/kg), acetylcholine (scopolamine; 0.1, 0.5, 1.0 mg/kg), glutamate (dizocilpine; 0.5, 1.5, 2.5 mg/kg), and serotonin (2,5-Dimethoxy-4-iodoamphetamine, DOI; 0.25, 0.5, 1.0 mg/kg). We determined PPI and startle amplitude for each drug in male and female Envigo and CR SD rats.

RESULTS

SD rats from Envigo showed dose-dependent decreases in PPI after apomorphine, scopolamine, or dizocilpine administration, without significant effects on startle amplitude. SD rats from CR were less sensitive to modulation of PPI and/or more sensitive to modulation of startle amplitude, across the three drugs.

CONCLUSIONS

SD rats showed vendor differences in sensitivity to pharmacological modulation of PPI and startle. We encourage researchers to sample rats from separate vendors before experimentation to identify the most suited source of subjects for their specific endpoints.

Distortion of Mendelian segregation across the Angus cattle genome uncovering regions affecting reproduction

Nowadays, the availability of genotyped trios (sire-dam-offspring) in the livestock industry enables the implementation of the transmission ratio distortion (TRD) approach to discover deleterious alleles in the genome. Various biological mechanisms at different stages of the reproductive cycle such as gametogenesis, embryo development and postnatal viability can induce signals of TRD (i.e., deviation from Mendelian inheritance expectations). In this study, TRD was evaluated using both SNP-by-SNP and sliding windows of 2-, 4-, 7-, 10- and 20-SNP across 92,942 autosomal SNPs for 258,140 genotyped Angus cattle including 7,486 sires, 72,688 dams and 205,966 offspring. Transmission ratio distortion was characterized using allelic (specific- and unspecific-parent TRD) and genotypic parameterizations (additive- and dominance-TRD). Across the Angus autosomal chromosomes, 851 regions were clearly found with decisive evidence for TRD. Among these findings, 19 haplotypes with recessive patterns (potential lethality for homozygote individuals) and 52 regions with allelic patterns exhibiting complete or quasi-complete absence for homozygous individuals in addition to under-representation (potentially reduced viability) of the carrier (heterozygous) offspring were found. In addition, 64 (12) and 20 (4) regions showed significant influence on the trait heifer pregnancy at p-value < 0.05 (after chromosome-wise false discovery rate) and 0.01, respectively, reducing the pregnancy rate up to 15%, thus, supporting the biological importance of TRD phenomenon in reproduction.

A-07 Initial Symptoms, Pre-Existing Emotional Factors, and Symptoms of Stress During Recovery from Concussion

Purpose: Investigate the association of initial symptoms, mechanism of concussion, and emotional state with symptoms of stress reported during recovery from concussion in high school students. Methods: Concussed High School students (n = 183) aged 13–18 were evaluated within 30 days of injury at a North Texas Concussion Registry (ConTex) clinic with 71% (n = 130) sport-related. Subjects completed a medical history, the Sport Concussion Assessment Tool-5 Symptom Evaluation (PCSS), General Anxiety Disorder (GAD-7), and Patient Health Questionnaire-8 (PHQ-8) at initial visit. At three-month follow-up subjects completed the PTSD Checklist for DSM-5 (PCL-5). A linear regression was conducted predicting total scores on the follow up PCL-5. Predictors included initial Total PCSS Symptom Score, GAD-7, PHQ-8, sex, mechanism of injury (sport vs non-sport) and history of treatment for anxiety/depression. Results: A multiple regression model predicting participant’s total PCL-5 score at three month follow-up (R2 = 0.40, p &lt; 0.001) included PHQ-8 (β = 0.34, p &lt; 0.001), GAD-7 (β = 0.20, p = 0.016), history of treatment for depression (β = 0.17, p = 0.015), severity of initial symptoms (β = 0.15, p = 0.045) and mechanism of injury (β = −0.14, p = 0.018). There was no significant difference in PCL-5 scores between sport vs non-sport injury groups. Conclusions: Pre-existing depression and higher levels of self-reported anxiety and/or depression at time of injury may be associated with increased symptoms of stress during concussion recovery. Severity of initial symptoms and mechanism of injury may also be related to feelings of stress during recovery. Further investigations should include baseline measure of stress prior to injury.

Oral Tau Aggregation Inhibitor for Alzheimer’s Disease: Design, Progress and Basis for Selection of the 16 mg/day Dose in a Phase 3, Randomized, Placebo-Controlled Trial of Hydromethylthionine Mesylate

Background

Hydromethylthionine mesylate is a tau aggregation inhibitor shown to have exposure-dependent pharmacological activity on cognitive decline and brain atrophy in two completed Phase 3 trials in mild/moderate Alzheimer’s disease (AD).

Objectives

The present report summarises the basis for selection of 16 mg/day as monotherapy as the optimal treatment regime and the design rationale of a confirmatory Phase 3 trial (LUCIDITY).

Design

The trial comprises a 12-month double-blind, placebo-controlled phase followed by a 12-month modified delayed-start open-label treatment phase.

Setting

76 clinical research sites in North America and Europe.

Participants

545 patients with probable AD or MCI-AD in the final version of the protocol.

Intervention

Participants were assigned randomly to receive hydromethylthione mesylate at doses of 16 mg/day, 8 mg/day or placebo at a 4:1:4 ratio during the double-blind phase. All participants in the open-label phase receive the 16 mg/day dose.

Measurements

Co-primary clinical outcomes are the 11-item Alzheimer’s Disease Assessment Scale (ADAS-cog₁₁) and the 23-item Alzheimer’s Disease Cooperative Study — Activities of Daily Living (ADCS-ADL₂₃). Secondary biomarker measures include whole-brain atrophy and temporal lobe ¹⁸F-fluorodeoxyglucose positron emission tomography.

Results

446 participants are expected to complete the 12-month placebo-controlled phase in March 2022.

Conclusions

If the primary end points are met, the data will provide confirmatory evidence of the clinical and biomarker benefits of hydromethylthionine mesylate in minimal to moderate AD. As low-dose oral hydromethylthionine mesylate is simple to use clinically, does not cause amyloid-related imaging abnormalities and has a benign safety profile, it would likely improve AD management.

A Rare Bird: Diagnosis of Psittacosis Meningitis by Clinical Metagenomic Next-Generation Sequencing

Psittacosis is a zoonotic infectious disease caused by the transmission of Chlamydia psittaci; it often presents as a pulmonary infection but rarely as disseminated disease. Because diagnoses of psittacosis are often underreported due to infrequent pathogen-specific testing, clinical metagenomic next-generation sequencing may be helpful to diagnose such an uncommon syndrome.

1100 A Closed Loop Audit Comparing Admission Rates Post Transurethral Resection of Bladder Tumour (TURBT) Before and After Day Case Procedure Was Made the Standard Goal

Aim

To assess the impact of making day case TURBT the standard goal.

Method

We performed a closed loop audit on the effect of listing all TURBTs as day case from the 1st December 2019. Data was collected retrospectively on all TURBTs from December 2018-March 2019, and from December 2019-March 2020 after implementing the change in protocol. Data collected included patient demographics, procedure and admission details, complications, and readmission rates.

Results

In total, 133 resections were included. Prior to the change in protocol, 36% of TURBTs were performed as day case. Of those admitted, 74% were due to haematuria, and 2% were planned. 8% were readmitted within 28 days and required urology input. There was 12% readmission rate overall. The rate of bladder perforation was 3.8%.

Post intervention, 64% of all TURBTs were performed as day case. 82% of admissions were due to haematuria, and 14% were planned. The rate of bladder perforation remained low at 1.6%, and readmission rate was 3% with no urology input required.

Conclusions

TURBT is the standard endoscopic procedure for the diagnosis, grading and removal of bladder tumours. The use of day case surgery pathways has been emphasised to help reduce lengths of stay and streamline patient care. The British Association of Day Surgery (BADS) recommends that 60% of TURBTs could be performed as a day case procedure. This study shows that this recommendation can be exceeded through a simple and low-cost intervention, whilst maintaining a low complication rate.

Dismantling myths on the airborne transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)

The coronavirus disease 2019 (COVID-19) pandemic has caused untold disruption throughout the world. Understanding the mechanisms for transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is key to preventing further spread, but there is confusion over the meaning of ‘airborne’ whenever transmission is discussed. Scientific ambivalence originates from evidence published many years ago which has generated mythological beliefs that obscure current thinking. This article collates and explores some of the most commonly held dogmas on airborne transmission in order to stimulate revision of the science in the light of current evidence. Six ‘myths’ are presented, explained and ultimately refuted on the basis of recently published papers and expert opinion from previous work related to similar viruses. There is little doubt that SARS-CoV-2 is transmitted via a range of airborne particle sizes subject to all the usual ventilation parameters and human behaviour. Experts from specialties encompassing aerosol studies, ventilation, engineering, physics, virology and clinical medicine have joined together to produce this review to consolidate the evidence for airborne transmission mechanisms, and offer justification for modern strategies for prevention and control of COVID-19 in health care and the community.

Hippocampal subfield pathologic burden in Lewy body diseases vs. Alzheimer's disease

AIMS

Lewy body diseases (LBD) are characterized by alpha-synuclein (SYN) pathology, but comorbid Alzheimer's disease (AD) pathology is common and the relationship between these pathologies in microanatomic hippocampal subfields is understudied. Here we use digital histological methods to test the association between hippocampal SYN pathology and the distribution of tau and amyloid-beta (Aβ) pathology in LBD and contrast with AD subjects. We also correlate pathologic burden with antemortem episodic memory testing.

METHODS

Hippocampal sections from 49 autopsy-confirmed LBD cases, 30 with no/low AD copathology (LBD - AD) and 19 with moderate/severe AD copathology (LBD + AD), and 30 AD patients were stained for SYN, tau, and Aβ. Sections underwent digital histological analysis of subfield pathological burden which was correlated with antemortem memory testing.

RESULTS

LBD - AD and LBD + AD had similar severity and distribution of SYN pathology (P > 0.05), CA2/3 being the most affected subfield (P < 0.02). In LBD, SYN correlated with tau across subfields (R = 0.49, P < 0.001). Tau burden was higher in AD than LBD + AD (P < 0.001), CA1/subiculum and entorhinal cortex (ERC) being most affected regions (P = 0.04 to <0.01). However, tau pathology in LBD - AD was greatest in CA2/3, which was equivalent to LBD + AD. Aβ severity and distribution was similar between LBD + AD and AD. Total hippocampal tau and CA2/3 tau was inversely correlated with memory performance in LBD (R = -0.52, -0.69, P = 0.04, 0.009).

CONCLUSIONS

Our findings suggest that tau burden in hippocampal subfields may map closely with the distribution of SYN pathology in subfield CA2/3 in LBD diverging from traditional AD and contribute to episodic memory dysfunction in LBD.

Pulmonary Lymphangioleiomyomatosis originates in the pleural mesothelial cell population

Lymphangioleiomyomatosis (LAM) is a cystic lung disease mainly affecting women, in which degradation of the lung parenchyma is associated with a cell of unknown provenance, known as a LAM cell. LAM cells carry TSC2 mutations and can be identified in the lung parenchyma by their expression of both smooth muscle actin and antigens characteristic of melanocytes and melanocytic tumors. The nature of the cell-of-origin of LAM is controversial, and despite continued research effort remains elusive. Further, it has not been possible to culture pulmonary LAM cells in vitro, and current research relies on cells and animal models which may not recapitulate all features of the disease. We noted aberrant expression of melanoma antigens in pleural mesothelial cells in lung tissue from LAM patients, indicating that these cells could be the precursors of parenchymal LAM cells. We hypothesise that loss of tuberin function following TSC2 mutation in the mesothelial cell lineage gives rise to the cell-of-origin of pulmonary LAM (P-LAM), and of other associated conditions commonly noted in LAM patients. The unique properties of mesothelial cells provide a straightforward explanation of the diverse presentation of LAM.

A-43 Post-Traumatic Stress Symptoms in Sport-Related Concussion and Orthopedic Injury: An Initial Comparison

Objective

Few studies have compared psychological responses to injury following sport-related concussion versus injury in general. The aim of this pilot investigation was to explore whether trauma-related stress symptoms differ between adolescents with sport-related concussion (SRC) vs. orthopedic injury (OI).

Method

Participants age 12-18 with SRC (n=48) or OI (n=12) presented to specialty clinics in the North Texas Concussion Registry (ConTex) within 21 days of injury (M= 6.7). Total scores from the PTSD Checklist for DSM-5 (PCL-5) were calculated (range=0-80). Independent t-test compared PCL-5 symptom scores between SRC and OI, and post-hoc analyses examined frequency of symptoms reported within each group.

Results

There was no significant difference between mean PCL-5 scores in SRC and OI groups, and both obtained scores above the typical cutoff for PTSD, defined as scores &gt;30 (range= 0-46; SRC=10%, OI=16%). Most commonly reported symptoms for both SRC and OI were sleep problems, feeling jumpy, and being “super alert.” SRC subjects were more likely to report difficulty concentrating (SRC=42%; OI=16%), while OI subjects were more likely to report feeling distant from other people (OI=50%; SRC=20%).

Conclusions

While total post-traumatic stress symptoms may not differ between SRC and OI groups, there may be differences in individual trauma-related symptoms based upon the nature of injury. Both injury groups may be susceptible to sleep difficulties and hypervigilance, yet SRC individuals may experience more cognitive complaints, while OI may report more feelings of isolation. Furture studies will need to use the PCL-5 with larger sample sizes and recovery indices to provide a more detailed comparison of the injury groups.

A-32 Acute Concussive Symptom Profiles in Adolescents and Young Adults with History of Depression and Anxiety

Objective

The aims of this study are (1) to examine the clinical symptom profiles of individuals with depression and/or anxiety history following a concussion and (2) to compare profile differences across groups.

Method

Participants aged 12-25 (n=129, mean=15.6) with premorbid diagnoses of depression (n=24), anxiety (n=50), or depression+anxiety (n=55) were evaluated within 21 days after sustaining a concussion as part of the North Texas Concussion Registry (ConTex) using the Post-Concussion Symptom Scale (PCSS). Following the model described by Kontos and Collins (2014), symptom clusters were derived from the PCSS to create six domains (cognitive/fatigue, vestibular, ocular, posttraumatic migraine, anxiety/mood, cervical). ANOVAs with Tukey’s post-hoc tests were conducted to compare domain symptom severity and total symptom severity across groups.

Results

There were no demographic differences between groups. A single symptom profile was prominent across each group, with the primary, secondary, and tertiary symptomatic domains being posttraumatic migraine, ocular, and cognitive/fatigue, respectively. Across each domain the depression+anxiety group was most symptomatic, followed in order by the depression and anxiety groups. The depression+anxiety group reported significantly higher anxiety/mood (M=2.0 vs. M=1.3) and cognitive/fatigue (M=2.9 vs M=2.1) symptom severity compared to the anxiety group. Group differences on total symptom severity approached significance (F=2.83, p=.06).

Conclusions

The observed symptom profiles suggest that the acute-concussive response is similar in adolescents and young adults with history of depression and/or anxiety. Multiple premorbid conditions, such as depression and anxiety, appear to magnify overall symptom severity. Further research is warranted to understand the relationship between symptom burden and premorbid mental health factors.

The H3+ ionosphere of Uranus: decades-long cooling and local-time morphology

The upper atmosphere of Uranus has been observed to be slowly cooling between 1993 and 2011. New analysis of near-infrared observations of emission from H3+ obtained between 2012 and 2018 reveals that this cooling trend has continued, showing that the upper atmosphere has cooled for 27 years, longer than the length of a nominal season of 21 years. The new observations have offered greater spatial resolution and higher sensitivity than previous ones, enabling the characterization of the H3+ intensity as a function of local time. These profiles peak between 13 and 15 h local time, later than models suggest. The NASA Infrared Telescope Facility iSHELL instrument also provides the detection of a bright H3+ signal on 16 October 2016, rotating into view from the dawn sector. This feature is consistent with an auroral signal, but is the only of its kind present in this comprehensive dataset. This article is part of a discussion meeting issue 'Advances in hydrogen molecular ions: H3+, H5+ and beyond'.

Modelling H3+ in planetary atmospheres: effects of vertical gradients on observed quantities

Since its detection in the aurorae of Jupiter approximately 30 years ago, the H3+ ion has served as an invaluable probe of giant planet upper atmospheres. However, the vast majority of monitoring of planetary H3+ radiation has followed from observations that rely on deriving parameters from column-integrated paths through the emitting layer. Here, we investigate the effects of density and temperature gradients along such paths on the measured H3+ spectrum and its resulting interpretation. In a non-isothermal atmosphere, H3+ column densities retrieved from such observations are found to represent a lower limit, reduced by 20% or more from the true atmospheric value. Global simulations of Uranus' ionosphere reveal that measured H3+ temperature variations are often attributable to well-understood solar zenith angle effects rather than indications of real atmospheric variability. Finally, based on these insights, a preliminary method of deriving vertical temperature structure is demonstrated at Jupiter using model reproductions of electron density and H3+ measurements. The sheer diversity and uncertainty of conditions in planetary atmospheres prohibits this work from providing blanket quantitative correction factors; nonetheless, we illustrate a few simple ways in which the already formidable utility of H3+ observations in understanding planetary atmospheres can be enhanced. This article is part of a discussion meeting issue 'Advances in hydrogen molecular ions: H3+, H5+ and beyond'.

B-51 Impact of Resilience on Symptoms and Mood during Recovery in Adolescents and Young Adults Following Sports-Related Concussion

Objective

It is unclear how resilience, the ability to “bounce back” from a stressful experience, is associated with recovery following a sport-related concussion (SRC). The aim of this project is to assess how resilience is related to symptoms following SRC.

Method

Participants (N = 353) aged 12-25 were evaluated within 30 days of injury at clinics in the ConTex Concussion Registry. The Sport Concussion Assessment Tool-5 symptom evaluation, Brief Resilience Scale (BRS), General Anxiety Disorder-7 Item (GAD-7), and Patient Health Questionnaire-8 Item (PHQ-8) were administered at initial visit and at three-months. BRS scores were used to place subjects into low (n = 40), average (n = 214), and high (n = 99) resilience groups, with a 2 (time) by 3 (group) repeated measures ANOVA to compare symptom scales.

Results

At initial visit subjects with low resilience reported higher GAD-7 [F (2,308) = 3.95, p = .02; 95% C.I. 5.19, 7.64] and PHQ-8 [F (2,311) = 4.40, p = .01; 95% C.I. 4.76, 7.47] scores compared to average and high resilience samples and demonstrated significant interaction effects with time. Subjects with low resilience also endorsed more initial SCAT5 symptoms [F (2,350) = 3.69, p = .026, 95% C.I. 10.99, 14.18] but showed no interaction with time.

Conclusion

Findings suggest that resilience may influence mood (anxiety & depression) initially and during SRC recovery. Consideration of resilience as a pre-injury factor may be important in SRC research.

The Role of Premorbid Psychiatric History and Current Mood Ratings on Self-Reported Concussion Symptom Severity

Purpose

Psychiatric history is known to be relevant to concussion outcomes, although less is known about the role of such factors or current mood ratings in adolescents. The aim of this study was to assess the role of premorbid psychiatric history (PPH) and current mood ratings (CMR) on overall sports-related concussion (SRC) symptomology and cognitive outcomes in adolescent and young adult athletes.

Methods

Participants age 12–25 years (M=14.8) diagnosed with SRC (n=560) were evaluated within 14 days of injury as part of the North Texas Concussion Registry (ConTex) using the Patient Health Questionnaire-8 Items (PHQ-8), General Anxiety Disorder-7 Item Scale (GAD-7), and ImPACT. Subjects were dichotomized into those with (PPH+) and without (PPH-) pre-existing reported psychiatric diagnoses, and CMR groups were determined by normal vs. elevated scores on the GAD-7 and PHQ-8. T-tests were used to compare groups.

Results

Significant differences in total symptom severity scores were found between both PPH (p=.01) and CMR (p<.001) groupings. PPH+ (n=27) reported significantly higher symptom scores (M=31.6) than PPH- subjects (n=316, M=20.9). Additionally, those reporting elevated CMR endorsed 2.3x higher symptom severity scores (n=48, M=42.1 vs. n=276, M=18.2). Among ImPACT cognitive scores, only Visual Memory differed between CMR groups (p=.047).

Conclusion

Findings suggest that PPH and elevated CMR are associated with greater self-reported symptom severity in adolescent SRC, but have little relationship to cognitive outcomes as assessed by ImPACT. Further research is needed to understand the interaction between PPH, CMR, and SRC recovery across the age spectrum.

Comparison of gait kinematics in total and unicondylar knee replacement surgery

INTRODUCTION

This study is aimed to compare kinematic gait data of patients who have undergone total and unicondylar knee replacement.

MATERIALS AND METHODS

This single-surgeon retrospective cohort study evaluated 13 patients with unilateral total knee arthroplasty (TKA) and 14 unicondylar knee arthroplasty (UKA). Gait analysis was carried out using a Vicon motion analysis system. The limits of knee flexion during stance phase, at heel strike and at loading response were measured.

RESULTS

The total range of motion of the UKA knees was significantly greater than the TKA knees. UKA knees exhibited significantly greater knee extension during the stance phase than the TKA knees. Unlike TKA, UKA knees demonstrated improved knee flexion during the gait cycle when compared to the contralateral non-operated knee. The hips also demonstrated near normal hip flexion in UKA patients. Predictably, UKA knees had significantly greater varus compared with TKA in the coronal plane. Spatiotemporal variables demonstrated similar walking speed and step length to aid a fair comparison between knee replacement groups.

CONCLUSIONS

The UKA knees moved more physiologically in the sagittal plane with a greater range of motion during gait. Despite having a stiff gait pattern, the patients undergoing TKA demonstrated a more neutral alignment in the coronal plane. Neither type of knee arthroplasty restored knee kinematics to those of the non-operated side.

TM2-2 Analysis of adverse events in the management of chronic headache by occipital nerve stimulation

Objectives

To analyse long-term adverse events of occipital nerve stimulation (ONS).

Design

Prospective open-label observational study.

Subjects

134 patients with refractory headaches implanted between 2007–2014 in a single specialised centre.

Methods

Information was collected on ONS device, implantable pulse generator (IPG) site and adverse event rates. The impact of implanter experience and the association between IPG site and adverse event rates was also explored.

Results

Mean follow up was 46 months (6–108 months). A total of 139 adverse events were recorded in 75 patients (56%). A total of 59 additional surgeries were needed in 39 patients. A significant difference was seen in the rates of adverse events recorded between 2007–2010 and 2011–2014 (60.7% vs 42.6%, p=0.002). A significant reduction in ONS revision was seen over time (25.7% vs 5.9%, p=0.002). Analysis of adverse events with IPG site showed those with abdominal implants recorded higher adverse event rate that those with an IPG in the chest (65.8% vs 40.3%, p=0.004).

Conclusions

In specialist centres, adverse event rates of ONS can be much lower than reported in the literature. Our results suggest implanter experience and IPG site both have an effect on adverse event rate.

WP1-1 Sphenopalatine ganglion stimulation for chronic cluster headache

Objectives

To assess outcome of sphenopalatine ganglion stimulation (SPGS) in chronic cluster headache (CCH) in a UK centre.

Design

Uncontrolled open-label single centre prospective study.

Subjects

Nine patients with medically refractory CCH.

Methods

Participants underwent sphenopalatine ganglion stimulator implantation, ipsilateral to CCH symptoms via a gingival incision, with fluoroscopy guidance and dyna-CT confirmation of contact location adjacent to the Vidian canal in the pterygopalatine fossa. One month after surgery, the device was programmed. Patients were instructed to provide stimulation as early as possible after attack onset and at least twice daily. The primary outcome was change in headache frequency as well as adverse events.

Results

Mean follow up was 14 months (SD 11.1, range: 3–31) with median reduction in headache frequency at last follow up of 73% (IQR: 67%–88%). At 3 months post op, 4/9 (45%) had at least 50% reduction in frequency of attacks; this increased to 8/9 patients (89%) at last follow up. Two patients became pain free (after 3 and 9 months). Preventative effects were seen in 7/9 and an acute effect in 2/9. One patient suffered numbness over the V2 distribution and did not respond to SPGS. The stimulator was removed 1 year later at the patient’s request. One wound infection settled with oral antibiotics.

Conclusions

Initial data from the UK confirms the results from previous studies and compares well with the results of occipital nerve stimulation for CCH.

Implementation of Bayesian methods to identify SNP and haplotype regions with transmission ratio distortion across the whole genome: TRDscan v.1.0

Realized deviations from the expected Mendelian inheritance of alleles from heterozygous parents have been previously reported in a broad range of organisms (i.e., transmission ratio distortion; TRD). Various biological mechanisms affecting gametes, embryos, fetuses, or even postnatal offspring can produce patterns of TRD. However, knowledge about its prevalence and potential causes in livestock species is still scarce. Specific Bayesian models have been recently developed for the analyses of TRD for biallelic loci, which accommodated a wide range of population structures, enabling TRD investigation in livestock populations. The parameterization of these models is flexible and allows the study of overall (parent-unspecific) TRD and sire- and dam-specific TRD. This research aimed at deriving Bayesian models for fitting TRD on the basis of haplotypes, testing the models for both haplotype- and SNP-based methods in simulated data and actual Holstein genotypes, and developing a specific software for TRD analyses. Results obtained on simulated data sets showed that the statistical power of the analysis increased with sample size of trios (n), proportion of heterozygous parents, and the magnitude of the TRD. On the other hand, the statistical power to detect TRD decreased with the number of alleles at each loci. Bayesian analyses showed a strong Pearson correlation coefficient (≥0.97) between simulated and estimated TRD that reached the significance level of Bayes factor ≥10 for both single-marker and haplotype analyses when n ≥ 25. Moreover, the accuracy in terms of the mean absolute error decreased with the increase of the sample size and increased with the number of alleles at each loci. Using real data (55,732 genotypes of Holstein trios), SNP- and haplotype-based distortions were detected with overall TRD, sire-TRD, or dam-TRD, showing different magnitudes of TRD and statistical relevance. Additionally, the haplotype-based method showed more ability to capture TRD compared with individual SNP. To discard possible random TRD in real data, an approximate empirical null distribution of TRD was developed. The program TRDscan v.1.0 was written in Fortran 2008 language and provides a powerful statistical tool to scan for TRD regions across the whole genome. This developed program is freely available at http://www.casellas.info/files/TRDscan.zip.

Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

OBJECTIVE

There are variable reports of risk of concordance for progression to islet autoantibodies and type 1 diabetes in identical twins after one twin is diagnosed. We examined development of positive autoantibodies and type 1 diabetes and the effects of genetic factors and common environment on autoantibody positivity in identical twins, nonidentical twins, and full siblings.

RESEARCH DESIGN AND METHODS

Subjects from the TrialNet Pathway to Prevention Study (N = 48,026) were screened from 2004 to 2015 for islet autoantibodies (GAD antibody [GADA], insulinoma-associated antigen 2 [IA-2A], and autoantibodies against insulin [IAA]). Of these subjects, 17,226 (157 identical twins, 283 nonidentical twins, and 16,786 full siblings) were followed for autoantibody positivity or type 1 diabetes for a median of 2.1 years.

RESULTS

At screening, identical twins were more likely to have positive GADA, IA-2A, and IAA than nonidentical twins or full siblings (all P < 0.0001). Younger age, male sex, and genetic factors were significant factors for expression of IA-2A, IAA, one or more positive autoantibodies, and two or more positive autoantibodies (all P ≤ 0.03). Initially autoantibody-positive identical twins had a 69% risk of diabetes by 3 years compared with 1.5% for initially autoantibody-negative identical twins. In nonidentical twins, type 1 diabetes risk by 3 years was 72% for initially multiple autoantibody-positive, 13% for single autoantibody-positive, and 0% for initially autoantibody-negative nonidentical twins. Full siblings had a 3-year type 1 diabetes risk of 47% for multiple autoantibody-positive, 12% for single autoantibody-positive, and 0.5% for initially autoantibody-negative subjects.

CONCLUSIONS

Risk of type 1 diabetes at 3 years is high for initially multiple and single autoantibody-positive identical twins and multiple autoantibody-positive nonidentical twins. Genetic predisposition, age, and male sex are significant risk factors for development of positive autoantibodies in twins.

Tripled yield in direct-drive laser fusion through statistical modelling

Focusing laser light onto a very small target can produce the conditions for laboratory-scale nuclear fusion of hydrogen isotopes. The lack of accurate predictive models, which are essential for the design of high-performance laser-fusion experiments, is a major obstacle to achieving thermonuclear ignition. Here we report a statistical approach that was used to design and quantitatively predict the results of implosions of solid deuterium-tritium targets carried out with the 30-kilojoule OMEGA laser system, leading to tripling of the fusion yield to its highest value so far for direct-drive laser fusion. When scaled to the laser energies of the National Ignition Facility (1.9 megajoules), these targets are predicted to produce a fusion energy output of about 500 kilojoules-several times larger than the fusion yields currently achieved at that facility. This approach could guide the exploration of the vast parameter space of thermonuclear ignition conditions and enhance our understanding of laser-fusion physics.