A taste of space: Remote animal observations and discrete-choice models provide new insights into foraging and density dynamics for a large subarctic herbivore

Competition for resources and space can drive forage selection of large herbivores from the bite through the landscape scale. Animal behaviour and foraging patterns are also influenced by abiotic and biotic factors. Fine-scale mechanisms of density-dependent foraging at the bite scale are likely consistent with density-dependent behavioural patterns observed at broader scales, but few studies have directly tested this assertion. Here, we tested if space use intensity, a proxy of spatiotemporal density, affects foraging mechanisms at fine spatial scales similarly to density-dependent effects observed at broader scales in caribou. We specifically assessed how behavioural choices are affected by space use intensity and environmental processes using behavioural state and forage selection data from caribou (Rangifer tarandus granti) observed from GPS video-camera collars using a multivariate discrete-choice modelling framework. We found that the probability of eating shrubs increased with increasing caribou space use intensity and cover of Salix spp. shrubs, whereas the probability of eating lichen decreased. Insects also affected fine-scale foraging behaviour by reducing the overall probability of eating. Strong eastward winds mitigated negative effects of insects and resulted in higher probabilities of eating lichen. At last, caribou exhibited foraging functional responses wherein their probability of selecting each food type increased as the availability (% cover) of that food increased. Space use intensity signals of fine-scale foraging were consistent with density-dependent responses observed at larger scales and with recent evidence suggesting declining reproductive rates in the same caribou population. Our results highlight potential risks of overgrazing on sensitive forage species such as lichen. Remote investigation of the functional responses of foraging behaviours provides exciting future applications where spatial models can identify high-quality habitats for conservation.

Investigation and response to an outbreak of Neisseria meningitidis serogroup Y ST-1466 urogenital infections, Australia

Abstract

In 2023, an increased number of urogenital and anorectal infections with Neisseria meningitis serogroup Y (MenY) were reported in New South Wales (NSW). Whole genome sequencing (WGS) found a common sequence type (ST-1466), with limited sequence diversity. Confirmed outbreak cases were NSW residents with a N. meningitidis isolate matching the cluster sequence type; probable cases were NSW residents with MenY isolated from a urogenital or anorectal site from 1 July 2023 without WGS testing. Of the 41 cases, most were men (n = 27), of whom six reported recent contact with a female sex worker. Five cases were men who have sex with men and two were female sex workers. Laboratory alerts regarding the outbreak were sent to all Australian jurisdictions through the laboratories in the National Neisseria Network. Two additional states identified urogenital MenY ST-1466 infections detected in late 2023. Genomic analysis showed all MenY ST-1466 sequences were interspersed, suggestive of an Australia-wide outbreak. The incidence of these infections remains unknown, due to varied testing and reporting practices both within and across jurisdictions. Isolates causing invasive meningococcal disease (IMD) in Australia are typed, and there has been no MenY ST-1466 IMD recorded in Australia to end of March 2024. Concerns remain regarding the risk of IMD, given the similarity of these sequences with a MenY ST-1466 IMD strain causing a concurrent outbreak in the United States of America.

Cancer-associated mesothelial cells are regulated by the anti-Müllerian hormone axis

Cancer-associated mesothelial cells (CAMCs) in the tumor microenvironment are thought to promote growth and immune evasion. We find that, in mouse and human ovarian tumors, cancer cells express anti-Müllerian hormone (AMH) while CAMCs express its receptor AMHR2, suggesting a paracrine axis. Factors secreted by cancer cells induce AMHR2 expression during their reprogramming into CAMCs in mouse and human in vitro models. Overexpression of AMHR2 in the Met5a mesothelial cell line is sufficient to induce expression of immunosuppressive cytokines and growth factors that stimulate ovarian cancer cell growth in an AMH-dependent way. Finally, syngeneic cancer cells implanted in transgenic mice with Amhr2-/- CAMCs grow significantly slower than in wild-type hosts. The cytokine profile of Amhr2-/- tumor-bearing mice is altered and their tumors express less immune checkpoint markers programmed-cell-death 1 (PD1) and cytotoxic T lymphocyte-associated protein 4 (CTLA4). Taken together, these data suggest that the AMH/AMHR2 axis plays a critical role in regulating the pro-tumoral function of CAMCs in ovarian cancer.

Comparison of the Journey II bicruciate stabilised (JII-BCS) and GENESIS II total knee arthroplasty for functional ability and motor impairment: the CAPAbility, blinded, randomised controlled trial

OBJECTIVES

To determine if a newer design of total knee replacement (TKR) (Journey II BCS) produces superior patient-reported outcomes scores and biomechanical outcomes than the older, more established design (Genesis II).

SETTING

Patients were recruited from an NHS University Hospital between July 2018 and October 2019 with surgery at two sites. Biomechanical and functional capacity measurements were at a University Movement and Exercise Laboratory.

PARTICIPANTS

80 participants undergoing single-stage TKR.

INTERVENTIONS

Patients were randomised to receive either the Journey II BCS (JII-BCS) or Genesis II TKR.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcome was the Oxford Knee Score (OKS), at 6 months. Secondary outcomes were: OKS Activity and Participation Questionnaire, EQ-5D-5L and UCLA Activity scores, Timed Up and Go Test, 6 min walk test, lower limb kinematics and lower limb muscle activity during walking and balance.

RESULTS

This study found no difference in the OKS between groups. The OKS scores for the JII-BCS and Genesis II groups were mean (SD) 42.97 (5.21) and 43.13 (5.20) respectively, adjusted effect size 0.35 (-2.01,2.71) p=0.771In secondary outcome measures, the Genesis II group demonstrated a significantly greater walking range-of-movement (50.62 (7.33) vs 46.07 (7.71) degrees, adjusted effect size, 3.14 (0.61,5.68) p=0.02) and higher peak knee flexion angular velocity during walking (mean (SD) 307.69 (38.96) vs 330.38 (41.40) degrees/second, adjusted effect size was 21.75 (4.54,38.96), p=0.01) and better postural control (smaller resultant centre of path length) during quiet standing than the JII-BCS group (mean (SD) 158.14 (65.40) vs 235.48 (176.94) mm, adjusted effect size, 59.91 (-105.98, -13.85) p=0.01.).

CONCLUSIONS

In this study population, the findings do not support the hypothesis that the Journey II BCS produces a better outcome than the Genesis II for the primary outcome of the OKS at 6 months after surgery.

TRIAL REGISTRATION NUMBER

ISRCTN32315753.

Analysis of Racial and Ethnic Diversity of Population Served and Imaging Used in US Children's Hospital Emergency Departments

Importance

Lower rates of diagnostic imaging have been observed among Black children compared with White children in pediatric emergency departments. Although the racial composition of the pediatric population served by each hospital differs, it is unclear whether this is associated with overall imaging rates at the hospital level, and in particular how it may be associated with the difference in imaging rates between Black and White children at a given hospital.

Objective

To examine the association between the diversity of the pediatric population seen at each pediatric ED and variation in diagnostic imaging.

Design, Setting, and Participants

Cross-sectional analysis of ED visits by patients younger than 18 years at 38 children's hospitals from January 1, 2016, through December 31, 2019, using data from the Pediatric Health Information System. Data were analyzed from April to September 2021.

Exposures

Proportion of patients from minoritized groups cared for at each hospital.

Main Outcomes and Measures

The primary outcome was receipt of an imaging test defined as radiography, ultrasonography, computed tomography, or magnetic resonance imaging; adjusted odds ratios (aORs) were calculated to measure differences in imaging by race and ethnicity by hospital, and the correlation between the proportion of patients from minoritized groups cared for at each hospital and the aOR for receipt of diagnostic imaging by race and ethnicity was examined.

Results

There were 12 310 344 ED visits (3 477 674 [28.3%] among Hispanic patients; 3 212 915 [26.1%] among non-Hispanic Black patients; 4 415 747 [35.9%] among non-Hispanic White patients; 6 487 660 [52.7%] among female patients) by 5 883 664 pediatric patients (mean [SD] age, 5.84 [5.23] years) to the 38 hospitals during the study period, of which 3 527 866 visits (28.7%) involved at least 1 diagnostic imaging test. Diagnostic imaging was performed in 1 508 382 visits (34.2%) for non-Hispanic White children, 790 961 (24.6%) for non-Hispanic Black children, and 907 222 (26.1%) for Hispanic children (P < .001). Non-Hispanic Black patients were consistently less likely to receive diagnostic imaging than non-Hispanic White patients at each hospital, and for all imaging modalities. There was a significant correlation between the proportion of patients from minoritized groups cared for at the hospital and greater imaging difference between non-Hispanic White and non-Hispanic Black patients (correlation coefficient, -0.37; 95% CI, -0.62 to -0.07; P = .02).

Conclusions and Relevance

In this cross-sectional study, hospitals with a higher percentage of pediatric patients from minoritized groups had larger differences in imaging between non-Hispanic Black and non-Hispanic White patients, with non-Hispanic White patients consistently more likely to receive diagnostic imaging. These findings emphasize the urgent need for interventions at the hospital level to improve equity in imaging in pediatric emergency medicine.

A248 THE ROLE OF DIETARY TRYPTOPHAN IN INDOLE AND KYNURENINE PRODUCTION AND IMMUNE MODULATION IN HEALTHY INDIVIDUALS

Background

Natural supplements are widely consumed by the general public, with little evidence of mechanistic support. Tryptophan has gained central attention, being transformed by host and gut microbial enzymes into multiple bioactive metabolites that regulate immunity and mood. Indoles are activators of the aryl hydrocarbon receptor (AhR), crucial for the maintenance of intestinal homeostasis. Tryptophan has been advocated to prevent chronic inflammatory conditions, however the clinical data to support this are missing.

Aims

To investigate clinical, immune, and metabolic parameters in response to tryptophan supplementation, in healthy subjects on a low tryptophan diet.

Methods

We performed a randomized, double blind, placebo-controlled crossover study in 20 healthy volunteers (18 - 75 years old). Subjects were instructed to start a low tryptophan diet and then randomly assigned to a 3-week tryptophan supplementation (3g/day) or placebo, in enteric coated capsules. After a 2-week washout period, subjects crossed over to the opposite intervention arm. Questionnaires were used to assess bowel symptoms, anxiety, depression and stress levels (GSRS, HADS and DASS21, respectively). Stool, urine, blood and duodenal aspirates were collected to measure tryptophan metabolites and cytokines.

Results

Tryptophan supplementation had no changes in gastrointestinal symptoms or behavioral parameters. Compared with placebo, tryptophan increased urinary and plasma levels of indoleamine 2,3-dioxygenase/kynurenine (p= 0.002 and p= 0.02, respectively) and indoles (p= 0.001 and p= 0.01, respectively), suggestive of activation of host and microbial metabolic pathways. Urinary and plasma metabolites were higher than in feces (p=<0.05), suggesting their active absorption in the small intestine. There were no differences in AhR activity in duodenal aspirates or in stool. Although no changes in the cytokine production were detected, serum kynurenine pathway metabolites negatively correlated with IL-8 levels (R=-0.72; p=0.001). Fecal tryptophan metabolites levels positively correlated with anxiety and depression scores, suggesting that the microbial metabolism of dietary tryptophan in the colon impacts host behavior.

Conclusions

Tryptophan supplementation in healthy individuals was safe and had a measurable influence on microbial and host metabolism, mainly kynurenine and indole pathways, with known immunomodulatory properties. Tryptophan was metabolized and absorbed in the small intestine, reflected by the high metabolite levels in plasma and urine. Fecal metabolites correlating with clinical parameters reflect subjects’ long-term diet. Further studies are warranted to study tryptophan supplementation in disorders with altered AhR pathways.

Funding Agencies

CIHR

Socioeconomic disparities in growth trajectories of Chinese children and adolescents during 1991-2015

Backgrounds

Socioeconomic (SEP) disparities in growth of children from low-/middle-income countries are not well understood, especially in countries experiencing rapid economic growth. We investigated how SEP disparities in child growth in China have changed over time.

Methods

Using the longitudinal data of 5,118 children and adolescents (7-18y) from China Health and Nutrition Survey (10 sweeps, 1991-2015), we derived four cohorts born in 1981-95, 1986-90, 1991-95, 1996-2000. We applied random-effects fractional polynomial models to estimate mean height and BMI trajectories for each gender separately, by socioeconomic position (SEP) for each cohort. SEP disparities were estimated as differences between high and low SEP groups (by community-level urbanization index, household income/capita, parental education, and occupational class). We also examined whether SEP disparities in nutritional status (stunting, thinness, overweight/obesity) have changed over time.

Results

Mean height and BMI increased across cohorts, with differences being greatest in adolescence. The increasing trend for height was similar in high and low SEP groups, thus positive SEP differences in mean height persisted across cohorts (e.g. for boys at 10y, were 3.8cm in the earliest and 2.9cm latest cohorts at by urbanization index, and were 3.6cm and 3.1cm by HH income). For BMI, the increasing trend was much faster in high (vs low) SEP groups, thus SEP differences in mean BMI increased across cohorts (e.g. for boys at 10y, increased from 0.5 to 0.8kg/m2 by urbanization index, and 0.4 to 1.1kg/m2 by HH income). Findings for stunting and overweight/obesity were consistent with those for height and BMI. No significant association was found between SEP and thinness.

Conclusions

Short stature is associated with lower SEP, whereas high BMI is associated with higher SEP among Chinese youths. Between 1991-2015 in China, inequalities in childhood BMI increased while those for height remained fairly constant.

Key messages

Short stature is associated with lower SEP, whereas high BMI is associated with higher SEP among Chinese youths. Between 1991-2015 in China, inequalities in childhood BMI increased while those for height remained fairly constant.

A cross-sectional study to evaluate the validity of a novel patient-reported outcome measure of medication adherence in Type 2 Diabetes

Introduction

The average medication adherence (MA) among patients in developed countries living with a chronic disease is estimated to be roughly 50%.(1) Non-adherence is multi-factorial, owing to socio-economic and clinical factors, as well as arguably the most important factor, patients’ health beliefs and experiences. Patient Reported Outcome Measures (PROMs) are often uni-dimensional in their assessment of drivers of MA. This study has evaluated a novel PROM as part of a wider international research initiative focused on Type 2 Diabetes (T2D) which assesses four key factors of MA referred to as Social (S), Psychological (P), Usage (U) and Rationale (R), in short SPUR®.

Aim

To compare the validity of SPUR® against previously validated PROMs in patients with T2D.

Methods

This South London cross-sectional study surveyed adult participants with a confirmed diagnosis of T2D prescribed a minimum of one anti-hyperglycaemic medicine. Surveys were administered face-to-face by community pharmacists using a convenience sampling method based on interactions with pharmacy patients. The survey consisted of questions relating to socio-demographic and clinical data, the SPUR® tool and three previously validated PROMs (BeMQ-General®, MARS-10® and BeMQ-Specific®) as comparators to evaluate factors P, U and R respectively. The Medication Possession Ratio (MPR), a measure of a patient’s pill count in a given time period, was used as an objective comparator of adherence. Pearson’s correlation coefficients (r) were calculated to determine the strength of association between the validated PROMs and SPUR®, with T tests used as a measure of significance (p=&lt;0.05) as an evaluation of validity for SPUR®.

Results

The survey response rate was 21.6% (n=149/690). The modal age range for participants was 60–69 years of age (40.1%, n=60). Participants were predominantly educated to degree level (29.5%, n=44), White (48.3%, n=72) and retired (28.9%, n=43). Overall, 47.6% (n=71) of participants identified as female. Body Mass Index (BMI) data were available for 88.6% (n=132) of the sample with 42.4% (n=56/132) reporting a BMI &gt;30. In ascending order, moderate to strong positive correlations were observed between SPUR® and the comparative PROMs for factors P (r=0.464, p=&lt;0.0001), U (r=0.595, p=&lt;0.0001) and R (r=0.719, p=&lt;0.0001), indicating SPUR® to be a reliable measure of those MA factors. When assessing MA objectively, SPUR® demonstrated the strongest correlation (r=0.281, p=&lt;0.0001) to MPR compared with the validated tools, with MARS-10® as the closest comparator (r=0.266, p=0.001). Despite this, SPUR® did not overestimate MA, 83.8% (n=125) of the sample was identified as adherent based on MPR compared to 53% (n=79) with SPUR®. The latter more closely reflecting HbA1c data which identified 55.4% (n=31/56) as adherent.

Conclusion

Study strengths include the implementation of validated PROMs and two objective MA measures; however, the study sample size was limited. SPUR® has demonstrated its validity against validated PROMs whilst predicting adherence levels without exaggeration, which is often attributed to crude objective measures such as MPR.(2) SPUR® may therefore holistically identify the multiple factors linked to non-adherence, thus supporting the design of individualised interventions.. Such interventions are deemed by the World Health Organisation as potentially more impactful than developing new treatments.(1)

References

1. Eduardo Sabaté (WHO/NMH/CCH). Adherence to long-term therapies: policy for action. World Heal Organ. Published online 2001.

2. Long JA, Wang A, Medvedeva EL, et al. Glucose control and medication adherence among veterans with diabetes and serious mental illness: Does collocation of primary care and mental health care matter? Diabetes Care. Published online 2014. doi:10.2337/dc13-0051

Challenges and recommendations for magnetic hyperthermia characterization measurements

PURPOSE

The localized heating of magnetic nanoparticles (MNPs) via the application of time-varying magnetic fields - a process known as magnetic field hyperthermia (MFH) - can greatly enhance existing options for cancer treatment; but for broad clinical uptake its optimization, reproducibility and safety must be comprehensively proven. As part of this effort, the quantification of MNP heating - characterized by the specific loss power (SLP), measured in W/g, or by the intrinsic loss power (ILP), in Hm²/kg - is frequently reported. However, in SLP/ILP measurements to date, the apparatus, the analysis techniques and the field conditions used by different researchers have varied greatly, leading to questions as to the reproducibility of the measurements.

MATERIALS AND METHODS

An interlaboratory study (across N = 21 European sites) of calorimetry measurements that constitutes a snapshot of the current state-of-the-art within the MFH community has been undertaken. Identical samples of two stable nanoparticle systems were distributed to all participating laboratories. Raw measurement data as well as the results of in-house analysis techniques were collected along with details of the measurement apparatus used. Raw measurement data was further reanalyzed by universal application of the corrected-slope method to examine relative influences of apparatus and results processing.

RESULTS

The data show that although there is very good intralaboratory repeatability, the overall interlaboratory measurement accuracy is poor, with the consolidated ILP data having standard deviations on the mean of ca. ± 30% to ± 40%. There is a strong systematic component to the uncertainties, and a clear rank correlation between the measuring laboratory and the ILP. Both of these are indications of a current lack of normalization in this field. A number of possible sources of systematic uncertainties are identified, and means determined to alleviate or minimize them. However, no single dominant factor was identified, and significant work remains to ascertain and remove the remaining uncertainty sources.

CONCLUSION

We conclude that the study reveals a current lack of harmonization in MFH characterization of MNPs, and highlights the growing need for standardized, quantitative characterization techniques for this emerging medical technology.

A8 DIETARY TRYPTOPHAN MODULATES KYNURENINE AND INDOLE PRODUCTION IN HEALTHY INDIVIDUALS

Background

Tryptophan is an essential amino acid that is transformed by host and gut microbial enzymes into multiple bioactive metabolites that regulate immunity, mood and circadian rhythms. In particular, indoles, produced by gut bacterial metabolism of tryptophan, have recently gained central attention. Indoles are activators of the aryl hydrocarbon receptor (AhR), which is crucial for the maintenance of intestinal homeostasis and immunity. Tryptophan supplementation in fortified foods have been advocated to prevent chronic inflammatory conditions, from autism to chronic inflammation. However, whether dietary tryptophan supplementation affects immune function, tryptophan metabolic pathways and gastrointestinal symptoms in healthy subjects, is unknown.

Aims

To assess whether tryptophan supplementation, in healthy subjects on a low tryptophan diet, induces changes in microbiota-derived metabolites (indoles), host cytokine production or gut symptoms.

Methods

We performed a randomized, double blind, placebo-controlled, crossover study in 20 healthy individuals, between 18 and 75 years old, following a regular diet. Subjects were instructed to start a standardized low tryptophan diet and were randomly assigned to a 3-week tryptophan supplement (3gr/day) or placebo. After a 2-week washout period, subjects were crossed over to the opposite 3-week intervention arm. Self-administered questionnaires (GSRS, DASS21 and HADS) were used to assess gastrointestinal symptoms and mood/anxiety/stress. Stool, urine and blood samples were collected to measure tryptophan metabolites (kynurenine pathway and indoles) and cytokines.

Results

Supplementation of tryptophan was well tolerated and no changes in gastrointestinal symptoms or mood/anxiety were found. Compared with placebo, tryptophan supplementation increased urinary and plasma levels of indoleamine 2,3-dioxygenase (p= 0.002 and p= 0.02, respectively), a key enzyme in the kynurenine pathway, and of several indoles (p= 0.0008 and p= 0.01, respectively), suggestive of activation of microbial and host metabolic pathways. However, there were no measurable changes in the host cytokine production. There was a positive correlation between fecal kynurenine levels and anxiety and depression scores, suggesting that microbial metabolites may impact host behavior in humans.

Conclusions

Dietary tryptophan supplementation in healthy individuals was safe and had a measurable effect on microbial and host metabolism, mainly kynurenine and indole pathways, with known immunomodulatory properties. Although no effects on cytokine production were found, further studies are warranted to investigate tryptophan supplementation in disorders with altered AhR pathway, such as inflammatory bowel disease, metabolic syndrome and celiac disease.

Funding Agencies

None

Ambroxol as a novel disease-modifying treatment for Parkinson's disease dementia: protocol for a single-centre, randomized, double-blind, placebo-controlled trial

BACKGROUND

Currently there are no disease-modifying treatments for Parkinson's disease dementia (PDD), a condition linked to aggregation of the protein α-synuclein in subcortical and cortical brain areas. One of the leading genetic risk factors for Parkinson's disease is being a carrier in the gene for β-Glucocerebrosidase (GCase; gene name GBA1). Studies in cell culture and animal models have shown that raising the levels of GCase can decrease levels of α-synuclein. Ambroxol is a pharmacological chaperone for GCase and is able to raise the levels of GCase and could therefore be a disease-modifying treatment for PDD. The aims of this trial are to determine if Ambroxol is safe and well-tolerated by individuals with PDD and if Ambroxol affects cognitive, biochemical, and neuroimaging measures.

METHODS

This is a phase II, single-centre, double-blind, randomized placebo-controlled trial involving 75 individuals with mild to moderate PDD. Participants will be randomized into Ambroxol high-dose (1050 mg/day), low-dose (525 mg/day), or placebo treatment arms. Assessments will be undertaken at baseline, 6-months, and 12-months follow up times. Primary outcome measures will be the Alzheimer's disease Assessment Scale-cognitive subscale (ADAS-Cog) and the ADCS Clinician's Global Impression of Change (CGIC). Secondary measures will include the Parkinson's disease Cognitive Rating Scale, Clinical Dementia Rating, Trail Making Test, Stroop Test, Unified Parkinson's disease Rating Scale, Purdue Pegboard, Timed Up and Go, and gait kinematics. Markers of neurodegeneration will include MRI and CSF measures. Pharmacokinetics and pharmacodynamics of Ambroxol will be examined through plasma levels during dose titration phase and evaluation of GCase activity in lymphocytes.

DISCUSSION

If found effective and safe, Ambroxol will be one of the first disease-modifying treatments for PDD.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02914366, 26 Sep 2016/retrospectively registered.

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.

Thomson scattering systems on C-2W field-reversed configuration plasma experiment

TAE Technologies' newly constructed C-2W experiment aims to improve the ion and electron temperatures in a sustained field-reversed configuration plasma. A suite of Thomson scattering systems has been designed and constructed for electron temperature and density profile measurements. The systems are designed for electron densities of 1 × 10¹² cm^-3 to 2 × 10¹⁴ cm^-3 and temperature ranges from 10 eV to 2 keV. The central system will provide profile measurements of T_e and n_e at 16 radial locations from r = -9 cm to r = 64 cm with a temporal resolution of 20 kHz for 4 pulses or 1 kHz for 30 pulses. The jet system will provide profile measurements of T_e and n_e at 5 radial locations in the open field region from r = -5 cm to r = 15 cm with a temporal resolution of 100 Hz. The central system and its components have been characterized, calibrated, installed, and commissioned. A maximum-likelihood algorithm has been applied for data processing and analysis.

Development of a three-wave far-infrared laser interferometry and polarimetry diagnostic system for the C-2W field-reversed configuration plasmas

Great advancements in modern field-reversed configuration (FRC) experiments motivated the development of a 14-chord three-wave far infrared (FIR) laser interferometry and polarimetry diagnostic system, which can provide simultaneous high temporal resolution measurements of density and Faraday rotation profiles with high accuracy. The unique challenges facing FIR diagnostics in high beta FRC plasmas are the extremely small (<0.5°) Faraday rotation angles, and severe laser beam refraction effects due to high density gradient and choice of long wavelength. The diagnostic system design and development are described with methods to overcome the challenges, and initial experimental data are also presented.

Presumed tuberculosis-associated uveitis: rising incidence and widening criteria for diagnosis in a non-endemic area

PurposeTo assess the incidence, clinical ocular involvement and effectiveness of anti-tuberculous treatment in patients with chronic uveitis presumed to be associated with tuberculosis in a non-endemic community.Patients and methodsRetrospective case series of patients with uveitis and evidence of tuberculosis, with no other identified cause of uveitis, who underwent a 6-month course of standard anti-tuberculosis treatment between 2008 and 2015. The response to treatment was assessed at 6 and 12 months after initiation of treatment.ResultsForty-eight patients were included of whom 36 (75%) were born outside the United Kingdom. Only five had concurrent active pulmonary or nodal tuberculosis. There were 85 affected eyes, including 25 with granulomatous anterior uveitis, 32 with retinal vasculitis (occlusive in 21), and 20 with multifocal choroiditis or serpiginous-like retinochoroiditis. Gamma-interferon testing was positive in 95%. Complete resolution at end point was seen in only 60%, but a further 19% were inflammation-free on topical steroid only. Resolution was lower (50%) in those with panuveitis compared to other anatomical types (75%). Sixty-four eyes (75%) had a LogMAR visual acuity of 0.1 or better at the end of the study.ConclusionsThe incidence of presumed tuberculosis-associated uveitis (TBU) has almost quadrupled in this region. The efficacy of treatment has not been enhanced by the introduction of gamma-interferon testing to support diagnosis. Some patients may require more prolonged antibiotic therapy to ensure quiescence, but chronic non-infective anterior uveitis may in any case follow treated TBU.

Study protocol: An investigation of mother-infant signalling during breastfeeding using a randomised trial to test the effectiveness of breastfeeding relaxation therapy on maternal psychological state, breast milk production and infant behaviour and growth

Background

The physiological and psychological signalling between mother and infant during lactation is one of the prominent mother-infant factors that may influence breastfeeding outcomes. The infant can ‘signal’ his needs through vocalisation, and the mother can respond by allowing or restricting nipple access, which might alter the breast milk composition or volume. This may lead to parent-offspring conflict during the lactation period. Challenging infant behaviour has also been associated with maternal psychological distress, which might affect breastfeeding performance. Most attempts to improve breastfeeding rates focus on providing additional support, yet many aspects of the breastfeeding process are poorly understood. Thus, our objective is to investigate mother-infant signalling during breastfeeding by manipulating maternal psychological state using a relaxation therapy intervention. The study will test the hypothesis that mothers who listen to the therapy will be more relaxed/less stressed and this will favourably alter breast milk composition and/or affect milk volume and hence influence infant outcomes.

Methods

A randomised controlled trial will be conducted in first-time breastfeeding mothers and their new-born infants. Pregnant mothers will be recruited at antenatal clinics in Selangor, Malaysia, and four home visits will be carried out at 2, 6, 12 and 14 weeks postnatally. Participants will be randomised into a control and an intervention group in the early post-partum period. Mothers from the intervention group will be asked to listen daily to an audio recording with relaxation therapy during breastfeeding. Maternal psychological state, breastfeeding practices and infant behaviour will be assessed using validated questionnaires. Milk volume will be measured using stable isotopes. Breast milk samples will be collected to measure macronutrient content and hormone levels. Anthropometric measurements (weight, length and head circumference) will be performed during all home visits, including body composition at week 14.

Discussion

The main outcomes will be the effect of the intervention on maternal psychological state, milk production, cortisol levels, and infant behaviour and growth. Secondary outcomes will be associations between breast milk composition and infant appetite and growth. This study aims to provide a greater understanding of maternal-infant factors which influence breastfeeding outcomes and which may be useful targets for future interventions.

Trial registration

ClinicalTrials.gov identifier: NCT01971216.

Dark Matter Search Results from the PICO-60 C_{3}F_{8} Bubble Chamber

New results are reported from the operation of the PICO-60 dark matter detector, a bubble chamber filled with 52 kg of C_{3}F_{8} located in the SNOLAB underground laboratory. As in previous PICO bubble chambers, PICO-60 C_{3}F_{8} exhibits excellent electron recoil and alpha decay rejection, and the observed multiple-scattering neutron rate indicates a single-scatter neutron background of less than one event per month. A blind analysis of an efficiency-corrected 1167-kg day exposure at a 3.3-keV thermodynamic threshold reveals no single-scattering nuclear recoil candidates, consistent with the predicted background. These results set the most stringent direct-detection constraint to date on the weakly interacting massive particle (WIMP)-proton spin-dependent cross section at 3.4×10^{-41}  cm^{2} for a 30-GeV c^{-2} WIMP, more than 1 order of magnitude improvement from previous PICO results.

Adjuvant sunitinib following chemoradiotherapy and surgery for locally advanced esophageal cancer: a phase II trial

The prognosis for locally advanced esophageal cancer is poor despite the use of trimodality therapy. In this phase II study, we report the feasibility, tolerability and efficacy of adjuvant sunitinib. Included were patients with stage IIa, IIB or III cancer of the thoracic esophagus or gastroesophageal junction. Neoadjuvant therapy involved Irinotecan (65 mg/m² ) + Cisplatin (30 mg/m² ) on weeks 1 and 2, 4 and 5, 7 and 8 with concurrent radiation (50Gy/25 fractions) on weeks 4-8. Sunitinib was commenced 4-13 weeks after surgery and continued for one year. Sixty-one patients were included in the final analysis, 36 patients commenced adjuvant sunitinib. Fourteen patients discontinued sunitinib due to disease recurrence (39%) within the 12-month period, 12 (33%) discontinued due to toxicity, and 3 (8%) requested cessation of therapy. In the overall population, median survival was 26 months with a 2 and 3-year survival rate of 52% and 35%, respectively. The median survival for the 36 patients treated with sunitinib was 35 months and 2-year survival probability of 68%. In a historical control, a prior phase II study with the same trimodality therapy (n = 43), median survival was 36 months, with a 2-year survival of 67%. Initiation of adjuvant sunitinib is feasible, but poorly tolerated, with no signal of additional benefit over trimodality therapy for locally advanced esophageal cancer.

Systematic chemical and molecular profiling of MLL-rearranged infant acute lymphoblastic leukemia reveals efficacy of romidepsin

To address the poor prognosis of mixed lineage leukemia (MLL)-rearranged infant acute lymphoblastic leukemia (iALL), we generated a panel of cell lines from primary patient samples and investigated cytotoxic responses to contemporary and novel Food and Drug Administration-approved chemotherapeutics. To characterize representation of primary disease within cell lines, molecular features were compared using RNA-sequencing and cytogenetics. High-throughput screening revealed variable efficacy of currently used drugs, however identified consistent efficacy of three novel drug classes: proteasome inhibitors, histone deacetylase inhibitors and cyclin-dependent kinase inhibitors. Gene expression of drug targets was highly reproducible comparing iALL cell lines to matched primary specimens. Histone deacetylase inhibitors, including romidepsin (ROM), enhanced the activity of a key component of iALL therapy, cytarabine (ARAC) in vitro and combined administration of ROM and ARAC to xenografted mice further reduced leukemia burden. Molecular studies showed that ROM reduces expression of cytidine deaminase, an enzyme involved in ARAC deactivation, and enhances the DNA damage-response to ARAC. In conclusion, we present a valuable resource for drug discovery, including the first systematic analysis of transcriptome reproducibility in vitro, and have identified ROM as a promising therapeutic for MLL-rearranged iALL.

Defining Rehabilitation Success in Older Adults with Dementia--Results from an Inpatient Geriatric Rehabilitation Unit

OBJECTIVE

To quantify the magnitude of functional recovery in older adults with and without dementia admitted to an inpatient geriatric rehabilitation program by measuring change in measures of global physical function and physical therapy treatment outcomes.

DESIGN

Retrospective cohort study.

SETTING

Rehabilitation academic hospital.

PARTICIPANTS

Consecutive subjects, with (N=65, age 81.9±6.0 y) and without (N=157, age 82.8±7.2 y) a dementia diagnosis, had assessment data at admission and discharge from inpatient geriatric rehabilitation unit.

INTERVENTIONS

Not applicable.

MEASUREMENTS

The Functional Independence Measure (FIM) was used to estimate level of independence on activities of daily living. The Berg Balance Scale (BBS), Timed Up and Go Test (TUG) and 2 Minute Walk Test (2MWT) were used to estimate functional mobility and endurance. The FIM (total, motor subscale, cognitive subscale scores) were used to calculate rehabilitation efficacy and efficiency scores.

RESULTS

After controlling for confounding, there was no group difference for gains on the BBS, TUG, 2MWT; there was no group difference on rehabilitation efficacy and efficiency values based on the FIM motor subscale. The magnitude of the rehabilitation gain using the total FIM score was statistically different between groups, people with dementia having smaller gains.

CONCLUSION

Older adults with a diagnosis of dementia are capable of making motor function recovery during inpatient sub-acute rehabilitation comparable to their peers without a dementia diagnosis. The metric used to evaluate functional recovery influences the determination of rehabilitation success between groups. Rehabilitation success should be defined among people with a dementia diagnosis by a change in the motor subscale of the FIM, rather than the total FIM score or the gain relative to the maximal FIM score.

Clinical practice models in nursing education: implication for students' mobility

BACKGROUND

In accordance with the process of nursing globalization, issues related to the increasing national and international mobility of student and qualified nurses are currently being debated. Identifying international differences and comparing similarities for mutual understanding, development and better harmonization of clinical training of undergraduate nursing students is recommended.

AIMS

The aim of the study was to describe and compare the nature of the nursing clinical practice education models adopted in different countries.

METHODS

A qualitative approach involving an expert panel of nurses was adopted. The Nominal Group Technique was employed to develop the initial research instrument for data collection. Eleven members of the UDINE-C network, representing institutions engaged in the process of professional nursing education and research (universities, high schools and clinical institutes), participated. Three data collection rounds were implemented. An analysis of the findings was performed, assuring rigour.

RESULTS

Differences and homogeneity are reported and discussed regarding: (a) the clinical learning requirements across countries; (b) the prerequisites and clinical learning process patterns; and (c) the progress and final evaluation of the competencies achieved.

CONCLUSIONS

A wider discussion is needed regarding nursing student exchange and internalization of clinical education in placements across European and non-European countries. A clear strategy for nursing education accreditation and harmonization of patterns of organization of clinical training at placements, as well as strategies of student assessment during this training, are recommended. There is also a need to develop international ethical guidelines for undergraduate nursing students gaining international experience.

Antibiotic-related acute kidney injury in patients undergoing elective joint replacement

The aim of this study was to determine if a change in antibiotic prophylaxis for routine hip and knee replacement was associated with an increased risk of acute renal impairment. We identified 238 patients (128 knees and 110 hips) who had received a single prophylactic dose of 1.5 g cefuroxime before joint replacement. We compared them with prospectively collected data from 254 patients (117 knees and 137 hips) who received a single prophylactic dose of 2 g flucloxacillin and a height- and gender-determined dose of gentamicin. The primary outcome measure was any new renal impairment as graded by clinically validated criteria. We identified four patients (1.69%) in the cefuroxime group who developed renal impairment. All four had mild impairment and all renal function was normal by the third post-operative day. The incidence of new-onset renal impairment was significantly higher in the flucloxacillin-and-gentamicin group at 9.45% (24 patients) (p < 0.001). Three of these patients remained with acute renal impairment after a week, although the serum creatinine levels in all subsequently returned to normal.