Stable fixed points of combinatorial threshold-linear networks

Combinatorial threshold-linear networks (CTLNs) are a special class of recurrent neural networks whose dynamics are tightly controlled by an underlying directed graph. Recurrent networks have long been used as models for associative memory and pattern completion, with stable fixed points playing the role of stored memory patterns in the network. In prior work, we showed that target-free cliques of the graph correspond to stable fixed points of the dynamics, and we conjectured that these are the only stable fixed points possible [1, 2]. In this paper, we prove that the conjecture holds in a variety of special cases, including for networks with very strong inhibition and graphs of size n ≤ 4 . We also provide further evi-dence for the conjecture by showing that sparse graphs and graphs that are nearly cliques can never support stable fixed points. Finally, we translate some results from extremal com-binatorics to obtain an upper bound on the number of stable fixed points of CTLNs in cases where the conjecture holds.

"We're not broken. We're human." A qualitative meta-synthesis of health-care providers' experiences participating in well-being programs

INTRODUCTION

Protecting health-care provider (HCP) well-being is imperative to preserve health-care workforce capital, performance, and patient care quality. Limited evidence exists for the long-term effectiveness of HCP well-being programs, with less known about physiotherapists specifically.

PURPOSE

To review and synthesize qualitative research describing experiences of HCP, generate lessons learned from the greater population of HCP participating in workplace well-being programs, and then to inform programs and policies for optimizing psychological well-being in an understudied population of physiotherapists.

METHODS

This qualitative meta-synthesis included a systematic literature search conducted in September 2020; critical appraisal of results; and data reduction, re-categorizing, and thematic extraction (reciprocal translation) with interpretive triangulation.

RESULTS

Twenty-five papers met the inclusion criteria. Participants included physicians, nurses, and allied health providers. All programs targeted the individual provider and included psychoeducational offerings, supervision groups, coaching, and complementary therapies. Four themes were constructed: 1) beneficial outcomes across a range of programs; 2) facilitators of program success; 3) barriers to program success; and 4) unmet needs driving recommendations.

CONCLUSIONS

The findings enhance our understanding of diverse individual-level programs to address HCP well-being. Beneficial outcomes were achieved across program types with system-level support proving critical; however, HCP described barriers to program success (HCP characteristics, off-site programs, institutional culture) and remaining needs (resources, ethical dissonance) left unaddressed. Organizations should offer individual-level programs to support physiotherapists in the short term while pursuing long-term, system-level change to address drivers of well-being.

Presumptive phenobarbital-induced systemic lupus erythematosus in a domestic dog

CASE DESCRIPTION

We describe a case of presumptive acquired systemic lupus erythematosus secondary to phenobarbital administration in a dog, which resolved with withdrawal of the drug.

CLINICAL FINDINGS

A 3.5 year-old poodle presented to a veterinary teaching hospital for Tier 1 idiopathic epilepsy and was treated with phenobarbital. The dog experienced fever, multiple cytopenias, and proteinuria in conjunction with a positive antinuclear antibody (ANA) titer.

DIAGNOSTICS

Serial CBCs, urine protein : creatinine ratios, and sternal bone marrow aspirates were performed to evaluate improvement.

TREATMENT AND OUTCOME

Phenobarbital was withdrawn and levetiracetam initiated. All abnormalities resolved with supportive care, without initiation of immunosuppressive drugs. All cytopenias and proteinuria resolved and ANA test results became negative within 3 months. The patient recovered and did well clinically.

CLINICAL RELEVANCE

Systemic lupus erythematosus is a disease of multiple autoimmune syndromes occurring concurrently or sequentially in conjunction with the presence of circulating ANA. It has been well described in dogs as an idiopathic condition, but in human medicine may occur secondary to drug reactions (drug-associated lupus) including as a reaction to phenobarbital. The findings in our case are consistent with the criteria for drug-induced lupus in humans and we suggest it as the first report of phenobarbital-induced lupus in a dog.

Superiority of BNCT Treatment Planning Metrics Achieved Using Novel vs. Reference (BPA-F) Pharmaceuticals in Head and Neck Locations

PURPOSE/OBJECTIVE(S)

Several novel boron delivery compounds currently under investigation by our group have demonstrated formulation, biodistribution, and dose response benefits in small animal models [1]. In this study we analyze the potential clinical impact of these compounds for boron neutron capture therapy (BNCT) in human patients.

MATERIALS/METHODS

Pharmacokinetic models were used to estimate the tumor and normal tissue boron concentrations after continuous infusion of the novel compounds and BPA-F. Patient model segmentation, material assignment, and alignment of one or more treatment beams were exported from a commercial treatment planning system (TPS) to a novel dose calculation tool. This information was used to generate a voxelized model that incorporated the source, beam shaping assembly, collimator, and patient materials so that the full albedo effect was included in each dose calculation. Physical dose from 10B(n,α), 14N(n,p), 1H(n,n') interactions plus gamma rays from 1H(n,γ) and other reactions within the patient and treatment equipment were calculated by Monte Carlo transport of particles originating in a pre-generated phase space at the cover surface. RBE and CBE weighting factors are applied to combine these four physical dose volumes into an equivalent dose volume, and these five dose volumes were passed back to the TPS for evaluation.

RESULTS

Tumor dose was increased by up to 2.6x for the novel compounds while normal tissue doses were constant or slightly reduced in comparison to BPA-F plans. Alternatively, for identical tumor dose the normal tissue doses and treatment time were reduced by up to 2.6x. In addition, in some cases it was possible to generate a single beam treatment plan using the new compounds that delivered higher tumor dose and lower normal tissues doses than a multiple beam plan using BPA-F.

CONCLUSION

This study demonstrates both dosimetric and practical benefits of the new compounds in comparison to BPA-F, including the potential to deliver treatment using fewer beam directions and correspondingly easier treatment setups and higher patient throughput. The potential of these compounds to extend the range of clinical indications for BNCT is also discussed. These results motivate upcoming experimental testing of the key assumptions involved in their calculation.

Surrogate Adiposity Markers and Mortality

Importance

Body mass index (BMI) is an easily obtained adiposity surrogate. However, there is variability in body composition and adipose tissue distribution between individuals with the same BMI, and there is controversy regarding the BMI associated with the lowest mortality risk.

Objective

To evaluate which of BMI, fat mass index (FMI), and waist-to-hip (WHR) has the strongest and most consistent association with mortality.

Design, Setting, and Participant

This cohort study used incident deaths from the UK Biobank (UKB; 2006-2022), which includes data from 22 clinical assessment centers across the United Kingdom. UKB British participants of British White ancestry (N = 387 672) were partitioned into a discovery cohort (n = 337 078) and validation cohort (n = 50 594), with the latter consisting of 25 297 deaths and 25 297 controls. The discovery cohort was used to derive genetically determined adiposity measures while the validation cohort was used for analyses. Exposure-outcome associations were analyzed through observational and mendelian randomization (MR) analyses.

Exposures

BMI, FMI, and WHR.

Main Outcomes and Measures

All-cause and cause-specific (cancer, cardiovascular disease [CVD], respiratory disease, or other causes) mortality.

Results

There were 387 672 and 50 594 participants in our observational (mean [SD] age, 56.9 [8.0] years; 177 340 [45.9%] male, 210 332 [54.2%], female), and MR (mean [SD] age, 61.6 [6.2] years; 30 031 [59.3%] male, 20 563 [40.6%], female) analyses, respectively. Associations between measured BMI and FMI with all-cause mortality were J-shaped, whereas the association of WHR with all-cause mortality was linear using the hazard ratio (HR) scale (HR per SD increase of WHR, 1.41 [95% CI, 1.38-1.43]). Genetically determined WHR had a stronger association with all-cause mortality than BMI (odds ratio [OR] per SD increase of WHR, 1.51 [95% CI, 1.32-1.72]; OR per SD increase of BMI, 1.29 [95% CI, 1.20-1.38]; P for heterogeneity = .02). This association was stronger in male than female participants (OR, 1.89 [95% CI, 1.54-2.32]; P for heterogeneity = .01). Unlike BMI or FMI, the genetically determined WHR-all-cause mortality association was consistent irrespective of observed BMI.

Conclusions and Relevance

In this cohort study, WHR had the strongest and most consistent association with mortality irrespective of BMI. Clinical recommendations should consider focusing on adiposity distribution compared with mass.

Severe obesity and global developmental delay in preschool children: Findings from a Canadian Paediatric Surveillance Program study

Background

The co-presentation of severe obesity (SO) and global developmental delay (GDD) in Canadian preschool children has not been examined. However, SO and GDD may require syndromic diagnoses and unique management considerations.

Objectives

To determine (1) minimum incidence; (2) age of onset and risk factors; and (3) health care utilization for co-presenting SO and GDD.

Methods

Through the Canadian Paediatric Surveillance Program (CPSP), a monthly form was distributed to participants from February 2018 to January 2020 asking for reports of new cases of SO and GDD among children ≤5 years of age. We performed descriptive statistics for quantitative questions and qualitative content analysis for open-ended questions.

Results

Forty-seven cases (64% male; 51% white; mean age: 3.5 ± 1.2 years) were included. Age of first weight concern was 2.5 ± 1.3 years and age of GDD diagnosis was 2.7 ± 1.4 years. Minimum incidence of SO and GDD was 3.3 cases per 100,000 for ≤5 years of age per year. Identified problems included school and/or behavioural problems (n = 17; 36%), snoring (n = 14; 30%), and asthma/recurrent wheeze (n = 10; 21%). Mothers of 32% of cases (n = 15) had obesity and 21% of cases (n = 10) received neonatal intensive care. Microarray was ordered for 57% (n = 27) of children. A variety of clinicians and services were accessed. As reported by CPSP participants, challenges faced by families and health service access were barriers to care.

Conclusion

Children with SO and GDD have multiple comorbidities, and require early identification and referral to appropriate services. These cases may also benefit from additional testing to rule out known genetic obesity syndromes.

Cyclic hematopoiesis in a mixed-breed dog: case report and brief review

An 8-wk-old, male, mixed-breed puppy was adopted from a rescue organization. From the time of adoption, the puppy suffered episodes of illness affecting various organ systems, which resolved with supportive therapy but relapsed once medical therapy was discontinued. Review of the hematologic data revealed cyclic fluctuations in circulating blood cells. Cyclicity was most prominent in neutrophils, with recurrent severe neutropenia. Neutropenic episodes lasted 5-6 d, with regular cycles of 11-14 d between nadir neutrophil counts. Genetic testing determined that the patient was homozygous mutant for the frameshift mutation in the adaptor protein complex 3 β-subunit (AP3B1) gene, originally identified in gray collies with cyclic hematopoiesis (CH). Pedigree information was not available, but the patient's features were phenotypically distinct from those of collies. We describe here a case of the AP3B1 mutation in a mixed-breed dog that did not resemble a collie, undescribed previously, to our knowledge. Our findings indicate that the AP3B1 mutation and CH are present within the general canine population and are not restricted to collies.

Maternal Schizophrenia and the Risk of a Childhood Chronic Condition

BACKGROUND AND HYPOTHESIS

Maternal schizophrenia heightens the risk for certain perinatal complications, yet it is not known to what degree future childhood chronic health conditions (Childhood-CC) might arise.

STUDY DESIGN

This population-based cohort study using health administrative data from Ontario, Canada (1995-2018) compared 5066 children of mothers with schizophrenia to 25 324 children of mothers without schizophrenia, propensity-matched on birth-year, maternal age, parity, immigrant status, income, region of residence, and maternal medical and psychiatric conditions other than schizophrenia. Cox proportional hazard models generated hazard ratios (HR) and 95% confidence intervals (CI) for incident Childhood-CCs, and all-cause mortality, up to age 19 years.

STUDY RESULTS

Six hundred and fifty-six children exposed to maternal schizophrenia developed a Childhood-CC (20.5/1000 person-years) vs. 2872 unexposed children (17.1/1000 person-years)-an HR of 1.18, 95% CI 1.08-1.28. Corresponding rates were 3.3 vs. 1.9/1000 person-years (1.77, 1.44-2.18) for mental health Childhood-CC, and 18.0 vs. 15.7/1000 person-years (1.13, 1.04-1.24) for non-mental health Childhood-CC. All-cause mortality rates were 1.2 vs. 0.8/1000 person-years (1.34, 0.96-1.89). Risk for children exposed to maternal schizophrenia was similar whether or not children were discharged to social service care. From age 1 year, risk was greater for children whose mothers were diagnosed with schizophrenia prior to pregnancy than for children whose mothers were diagnosed with schizophrenia postnatally.

CONCLUSIONS

A child exposed to maternal schizophrenia is at elevated risk of chronic health conditions including mental and physical subtypes. Future research should examine what explains the increased risk particularly for physical health conditions, and what preventive and treatment efforts are needed for these children.

Burnout and the role of authentic leadership in academic medicine

Background

Recently, there has been increasing evidence that reducing burnout in healthcare providers requires significant organizational efforts that include the integration of leadership strategies.

Methods

Focus groups were conducted across four health systems within the University of Colorado Department of Medicine in four affinity groups (administrative staff, medical trainees, research faculty, and clinical faculty). Authentic leadership theory was used for analysis to advance the understanding of the role of leadership style upon participants’ work experiences and preferences, and to identify opportunities for translation of site-specific results to other academic medical settings.

Results

Study participants from each affinity group believed their clinical leaders lacked objectivity with decision-making (lacking “balancing processing”), which contributed to their overall feeling of powerlessness. The experience of increasing work demands was salient throughout all twelve focus groups, and participants identified leadership that interacted in a more open and self-disclosing manner (“relational transparency”) as alleviating at least some of this burden. Strong preference discernable alignment between their leaders’ decision-making and their internal moral compass of values (demonstrating “internalized moral perspective”) was described, as was clinical leaders demonstrating “self-awareness” (having a self-reflective process that informs the leader’s decision-making). Comparing affinity group experiences within each authentic leadership theory construct identified the relevance of contextual factors, such as work setting and roles, upon employees’ perceptions and expectations of their leaders.

Conclusions

Use of authentic leadership theory advanced the understanding of the association between leadership traits and experiences of burnout amongst a large group of academic clinicians, researchers, trainees, and administrative staff. Leadership styles that promoted relationship transparency, openness, and support were preferred and fostering these traits may help address the demands in academic medicine, including symptoms of burnout.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-08034-x.

Core motifs predict dynamic attractors in combinatorial threshold-linear networks

Combinatorial threshold-linear networks (CTLNs) are a special class of inhibition-dominated TLNs defined from directed graphs. Like more general TLNs, they display a wide variety of nonlinear dynamics including multistability, limit cycles, quasiperiodic attractors, and chaos. In prior work, we have developed a detailed mathematical theory relating stable and unstable fixed points of CTLNs to graph-theoretic properties of the underlying network. Here we find that a special type of fixed points, corresponding to core motifs, are predictive of both static and dynamic attractors. Moreover, the attractors can be found by choosing initial conditions that are small perturbations of these fixed points. This motivates us to hypothesize that dynamic attractors of a network correspond to unstable fixed points supported on core motifs. We tested this hypothesis on a large family of directed graphs of size n = 5, and found remarkable agreement. Furthermore, we discovered that core motifs with similar embeddings give rise to nearly identical attractors. This allowed us to classify attractors based on structurally-defined graph families. Our results suggest that graphical properties of the connectivity can be used to predict a network’s complex repertoire of nonlinear dynamics.

Efficacy of the Aim2Be intervention in changing lifestyle behaviours among adolescents with overweight and obesity: A Randomized Controlled Trial (Preprint)

BACKGROUND

Aim2Be is a gamified lifestyle app designed to promote lifestyle behavior changes among Canadian adolescents and their families.

OBJECTIVE

The primary aim was to test the efficacy of the Aim2Be app with support from a live coach to reduce weight outcomes (BMI Z score [zBMI]) and improve lifestyle behaviors among adolescents with overweight and obesity and their parents versus a waitlist control group over 3 months. The secondary aim was to compare health trajectories among waitlist control participants over 6 months (before and after receiving access to the app), assess whether support from a live coach enhanced intervention impact, and evaluate whether the app use influenced changes among intervention participants.

METHODS

A 2-arm parallel randomized controlled trial was conducted from November 2018 to June 2020. Adolescents aged 10 to 17 years with overweight or obesity and their parents were randomized into an intervention group (Aim2Be with a live coach for 6 months) or a waitlist control group (Aim2Be with no live coach; accessed after 3 months). Adolescents' assessments at baseline and at 3 and 6 months included measured height and weight, 24-hour dietary recalls, and daily step counts measured with a Fitbit. Data on self-reported physical activity, screen time, fruit and vegetable intake, and sugary beverage intake of adolescents and parents were also collected.

RESULTS

A total of 214 parent-child participants were randomized. In our primary analyses, there were no significant differences in zBMI or any of the health behaviors between the intervention and control groups at 3 months. In our secondary analyses, among waitlist control participants, zBMI (P=.02), discretionary calories (P=.03), and physical activity outside of school (P=.001) declined, whereas daily screen time increased (P<.001) after receiving access to the app compared with before receiving app access. Adolescents randomized to Aim2Be with live coaching reported more time being active outside of school compared with adolescents who used Aim2Be with no coaching over 3 months (P=.001). App use did not modify any changes in outcomes among adolescents in the intervention group.

CONCLUSIONS

The Aim2Be intervention did not improve zBMI and lifestyle behaviors in adolescents with overweight and obesity compared with the waitlist control group over 3 months. Future studies should explore the potential mediators of changes in zBMI and lifestyle behaviors as well as predictors of engagement.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03651284; https://clinicaltrials.gov/ct2/show/study/NCT03651284.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.1186/s13063-020-4080-2.

Serum metabolomic signatures of gestational diabetes in South Asian and white European women

INTRODUCTION

This study aimed to identify serum metabolomic signatures associated with gestational diabetes mellitus (GDM), and to examine if ethnic-specific differences exist between South Asian and white European women.

RESEARCH DESIGN AND METHODS

Prospective cohort study with a nested case-control analysis of 600 pregnant women from two Canadian birth cohorts; using an untargeted approach, 63 fasting serum metabolites were measured and analyzed using multisegment injection-capillary electrophoresis-mass spectrometry. Multivariate logistic regression modeling was conducted overall and by cohort.

RESULTS

The proportion of women with GDM was higher in South Asians (27.1%) compared with white Europeans (17.9%). Several amino acid, carbohydrate, and lipid pathways related to GDM were common to South Asian and white European women. Elevated circulating concentrations of glutamic acid, propionylcarnitine, tryptophan, arginine, 2-hydroxybutyric acid, 3-hydroxybutyric acid, and 3-methyl-2-oxovaleric acid were associated with higher odds of GDM, while higher glutamine, ornithine, oxoproline, cystine, glycine with lower odds of GDM. Per SD increase in glucose concentration, the odds of GDM increased (OR=2.07, 95% CI 1.58 to 2.71), similarly for metabolite ratios: glucose to glutamine (OR=2.15, 95% CI 1.65 to 2.80), glucose to creatinine (OR=1.79, 95% CI 1.39 to 2.32), and glutamic acid to glutamine (OR=1.46, 95% CI 1.16 to 1.83). South Asians had higher circulating ratios of glucose to glutamine, glucose to creatinine, arginine to ornithine, and citrulline to ornithine, compared with white Europeans.

CONCLUSIONS

We identified a panel of serum metabolites implicated in GDM pathophysiology, consistent in South Asian and white European women. The metabolic alterations leading to larger ratios of glucose to glutamine, glucose to creatinine, arginine to ornithine, and citrulline to ornithine in South Asians likely reflect the greater burden of GDM among South Asians compared with white Europeans.

DNA methylation changes in cord blood and the developmental origins of health and disease – a systematic review and replication study

Background

Environmental exposures in utero which modify DNA methylation may have a long-lasting impact on health and disease in offspring. We aimed to identify and replicate previously published genomic loci where DNA methylation changes are attributable to in utero exposures in the NutriGen birth cohort studies Alliance.

Methods

We reviewed the literature to identify differentially methylated sites of newborn DNA which are associated with the following five traits of interest maternal diabetes, pre-pregnancy body mass index (BMI), diet during pregnancy, smoking, and gestational age. We then attempted to replicate these published associations in the Canadian Healthy Infant Longitudinal Development (CHILD) and the South Asian birth cohort (START) cord blood epigenome-wide data.

Results

We screened 68 full-text articles and identified a total of 17 cord blood epigenome-wide association studies (EWAS) of the traits of interest. Out of the 290 CpG sites reported, 19 were identified in more than one study; all of them associated with maternal smoking. In CHILD and START EWAS, thousands of sites associated with gestational age were identified and maintained significance after correction for multiple testing. In CHILD, there was differential methylation observed for 8 of the published maternal smoking sites. No other traits tested (i.e., folate levels, gestational diabetes, birthweight) replicated in the CHILD or START cohorts.

Conclusions

Maternal smoking during pregnancy and gestational age are strongly associated with differential methylation in offspring cord blood, as assessed in the EWAS literature and our birth cohorts. There are a limited number of reported methylation sites associated in more than two independent studies related to pregnancy. Additional large studies of diverse populations with fine phenotyping are needed to produce robust epigenome-wide data in order to further elucidate the effect of intrauterine exposures on the infants’ methylome.

Sequential Attractors in Combinatorial Threshold-Linear Networks

Sequences of neural activity arise in many brain areas, including cortex, hippocampus, and central pattern generator circuits that underlie rhythmic behaviors like locomotion. While network architectures supporting sequence generation vary considerably, a common feature is an abundance of inhibition. In this work, we focus on architectures that support sequential activity in recurrently connected networks with inhibition-dominated dynamics. Specifically, we study emergent sequences in a special family of threshold-linear networks, called combinatorial threshold-linear networks (CTLNs), whose connectivity matrices are defined from directed graphs. Such networks naturally give rise to an abundance of sequences whose dynamics are tightly connected to the underlying graph. We find that architectures based on generalizations of cycle graphs produce limit cycle attractors that can be activated to generate transient or persistent (repeating) sequences. Each architecture type gives rise to an infinite family of graphs that can be built from arbitrary component subgraphs. Moreover, we prove a number of graph rules for the corresponding CTLNs in each family. The graph rules allow us to strongly constrain, and in some cases fully determine, the fixed points of the network in terms of the fixed points of the component subnetworks. Finally, we also show how the structure of certain architectures gives insight into the sequential dynamics of the corresponding attractor.

Common Core Assessments in follow-up studies of adults born preterm-Recommendation of the Adults Born Preterm International Collaboration

BACKGROUND

Of all newborns, 1%-2% are born very preterm (VP; <32 weeks) or with very low birthweight (VLBW; ≤1500 g). Advances in prenatal and neonatal care have substantially improved their survival, and the first generations who have benefited from these advances are now entering middle age. While most lead healthy lives, on average these adults are characterised by a number of adversities. These include cardiometabolic risk factors, airway obstruction, less physical activity, poorer visual function, lower cognitive performance, and a behavioural phenotype that includes inattention and internalising and socially withdrawn behaviour that may affect life chances and quality of life. Outcomes in later adulthood are largely unknown, and identifying trajectories of risk or resilience is essential in developing targeted interventions. Joint analyses of data and maintenance of follow-up of cohorts entering adulthood are essential. Such analyses are ongoing within the Adults Born Preterm International Collaboration (APIC; www.apic-preterm.org). Joint analyses require data harmonisation, highlighting the importance of consistent assessment methodologies.

OBJECTIVE

To present an expert recommendation on Common Core Assessments to be used in follow-up assessments of adults born preterm.

METHODS

Principles of Common Core Assessments were discussed at APIC meetings. Experts for each specific outcome domain wrote the first draft on assessments pertaining to that outcome. These drafts were combined and reviewed by all authors. Consensus was reached by discussion at APIC meetings.

RESULTS

We present a recommendation by APIC experts on consistent measures to be used in adult follow-up assessments.

CONCLUSIONS

The recommendation encompasses both "core" measures which we recommend to use in all assessments of adults born preterm that include the particular outcome. This will allow comparability between time and location. The recommendation also lists optional measures, focusing on current gaps in knowledge. It includes sections on study design, cardiometabolic and related biomarkers, biological samples, life style, respiratory, ophthalmic, cognitive, mental health, personality, quality of life, sociodemographics, social relationships, and reproduction.

COVID-19's impact on faculty and staff at a School of Medicine in the US: what is the blueprint for the future?

Background

The Coronavirus Disease 2019 (COVID-19) caused unprecedented challenges within medical centers, revealing inequities embedded in the medical community and exposing fragile social support systems. While faculty and staff faced extraordinary demands in workplace duties, personal responsibilities also increased. The goal of this study was to understand the impact of the COVID-19 pandemic on personal and professional activities of faculty and staff in order to illuminate current challenges and explore solutions.

Methods

Qualitative, semi-structured group interviews involved faculty and staff at four affiliate sites within the Department of Medicine at the University of Colorado, School of Medicine. Focus groups addressed the impact of COVID-19 on (1) Changes to roles and responsibilities at work and at home, (2) Resources utilized to manage these changes and, (3) Potential strategies for how the Department could assist faculty and staff. Thematic analysis was conducted using an inductive method at the semantic level to form themes and subthemes.

Results

Qualitative analysis of focus group transcripts revealed themes of: (1) Challenges and disparities experienced during the pandemic, (2) Disproportionate impact on women personally and professionally, (3) Institutional factors that contributed to wellness and burnout, and (4) Solutions and strategies to support faculty and staff. Within each of these themes were multiple subthemes including increased professional and personal demands, concern for personal safety, a sense of internal guilt, financial uncertainty, missed professional opportunities, and a negative impact on mentoring. Solutions were offered and included an emphasis on addressing preexisting inequities, the importance of community, and workplace flexibility.

Conclusions

The COVID-19 pandemic created burdens for already challenged faculty and staff in both their personal and professional lives. Swift action and advocacy by academic institutions is needed to support the lives and careers of our colleagues now and in the future.

The effective coupling coefficient for a completed PIN-PMN-PT array

The computation of the electromechanical coupling coefficient (EMCC) of a fully assembled medical ultrasound transducer array is directly computed with closed form expressions. The Levenberg-Marquardt non-linear regression algorithm (LMA) is employed to help confirm the EMCC calculated prediction (k_EFF) and provide statistical insights. The complex electrical impedance spectra of a 1-3 composite array with two matching layers operating at a 3.75 MHz center frequency using PIN-PMN-PT single crystal material is measured in air both before and after oven heating at 160 °C for 15 min. The oven heating produces changes in the EMCC of -4.9%, clamped dielectric constant of -11%, and effective transducer longitudinal velocity of -2.5%. Utilizing the pre- and post-heating array impedance data, the calculated EMCC values from the new closed form expressions agree well with the complete KLM model based LMA, and also exhibit approximately one tenth the error as compared to the formulas for a flat, unloaded transducer.

Measurement of the heat flux normalized spin Seebeck coefficient of thin films as a function of temperature

The spin Seebeck effect (SSE) has generated interest in the thermoelectric and magnetic communities for potential high efficiency energy harvesting applications and spintronic communities as a source of pure spin current. Understanding the underlying mechanisms requires characterization of potential materials across a range of temperatures; however, for thin films, the default measurement of an applied temperature gradient (across the sample) has been shown to be compromised by the presence of thermal resistances. Here, we demonstrate a method to perform low temperature SSE measurements where, instead of monitoring the temperature gradient, the heat flux passing through the sample is measured using two calibrated heat flux sensors. This has the advantage of measuring the heat loss through the sample as well as providing a reliable method to normalize the SSE response of thin film samples. We demonstrate this method with an SiO₂/Fe₃O₄/Pt sample where a semiconducting-insulating transition occurs at the Verwey transition, T_V, of Fe₃O₄ and quantify the thermomagnetic response above and below T_V.

"Health, wealth and achievements of former very premature infants in adult life"

Very preterm survivors born in the early neonatal intensive care era are now in their middle adulthood. The literature from cohort studies and population-linked registries indicate that extreme prematurity is associated with lower educational attainment and income, higher need for social assistance, and lower rates of marriage/partnership and reproduction. In addition, with increasing age, many general and system-specific adverse health outcomes, such as psychiatric problems, hypertension, and cardio-metabolic disorders have emerged, resulting in high cumulative health care costs across the life-span. Yet, a significant majority of adults born preterm are leading productive lives and contributing to society. Although this information may not be directly applicable to survivors of modern neonatal intensive care, there is much to learn from these findings to inform and guide us into designing effective strategies to improve the health and well-being of future very premature infants. The longer-term outcome of more recent survivors remains to be determined.

Algebraic signatures of convex and non-convex codes

A convex code is a binary code generated by the pattern of intersections of a collection of open convex sets in some Euclidean space. Convex codes are relevant to neuroscience as they arise from the activity of neurons that have convex receptive fields. In this paper, we use algebraic methods to determine if a code is convex. Specifically, we use the neural ideal of a code, which is a generalization of the Stanley-Reisner ideal. Using the neural ideal together with its standard generating set, the canonical form, we provide algebraic signatures of certain families of codes that are non-convex. We connect these signatures to the precise conditions on the arrangement of sets that prevent the codes from being convex. Finally, we also provide algebraic signatures for some families of codes that are convex, including the class of intersection-complete codes. These results allow us to detect convexity and non-convexity in a variety of situations, and point to some interesting open questions.

Canadian Cardiovascular Society Position Statement on Familial Hypercholesterolemia: Update 2018

Familial hypercholesterolemia (FH) is the most common monogenic disorder causing premature atherosclerotic cardiovascular disease. It affects 1 in 250 individuals worldwide, and of the approximately 145,000 Canadians estimated to have FH, most are undiagnosed. Herein, we provide an update of the 2014 Canadian Cardiovascular Society position statement on FH addressing the need for case identification, prompt recognition, and treatment with statins and ezetimibe, and cascade family screening. We provide a new Canadian definition for FH and tools for clinicians to make a diagnosis. The risk of atherosclerotic cardiovascular disease in patients with "definite" FH is 10- to 20-fold that of a normolipidemic individual and initiating treatment in youth or young adulthood can normalize life expectancy. Target levels for low-density lipoprotein cholesterol are proposed and are aligned with the Canadian Cardiovascular Society guidelines on dyslipidemia. Recommendation for the use of inhibitors of proprotein convertase kexin/subtilisin type 9 are made in patients who cannot achieve therapeutic low-density lipoprotein cholesterol targets on maximally tolerated statins and ezetimibe. The writing committee used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology in the preparation of the present document, which offers guidance for practical evaluation and management of patients with FH. This position statement also aims to raise awareness of FH nationally, and to mobilize patient support, promote knowledge translation, and availability of treatment and health care resources for this under-recognized, but important medical condition.

Relating network connectivity to dynamics: opportunities and challenges for theoretical neuroscience

We review recent work relating network connectivity to the dynamics of neural activity. While concepts stemming from network science provide a valuable starting point, the interpretation of graph-theoretic structures and measures can be highly dependent on the dynamics associated to the network. Properties that are quite meaningful for linear dynamics, such as random walk and network flow models, may be of limited relevance in the neuroscience setting. Theoretical and computational neuroscience are playing a vital role in understanding the relationship between network connectivity and the nonlinear dynamics associated to neural networks.

Childhood Motor Coordination and Adult Affective Experience Among Extremely Low Birth Weight Survivors

Poor motor coordination in childhood has been associated in adulthood with more negative affect, less positive affect, and an increased risk of psychopathology. While survivors of extremely low birth weight (ELBW; < 1,000 grams) are more likely to manifest poor motor coordination than people born at normal birth weight (NBW; > 2,500 g), they have had better mental health outcomes than those with NBW who have motor difficulties. How emotion is experienced is an important risk factor for mental illness; yet, little is known about the affective experience of survivors of ELBW who also have poor motor coordination. In this longitudinal study, we examined interactions between birth weight status and childhood motor coordination on affective experience among 88 ELBW and 89 NBW participants. We first assessed childhood motor coordination at eight years of age, using the Bruininks-Oseretsky Test of Motor Proficiency, and we later gathered self-report data regarding affective style, using the Positive and Negative Affect Scedule and the Affective Styles Questionnaire, when these participants were 30-35 years of age. We found a statistically significant interaction between motor coordination and birth weight status. As motor coordination worsened among ELBW survivors, positive affect increased, while we observed the opposite trend in NBW participants (p < 0.05). There was no interaction for negative affect. Positive affect may contribute to previous findings of better relative adult mental health among ELBW survivors with poor childhood motor coordination. Strategies aimed at optimizing positive affect may be fruitful for optimizing mental health outcomes among preterm survivors and others with reduced motor proficiency.

Employers' Perspectives on Accommodating and Retaining Employees with Newly Acquired Disabilities: An Exploratory Study

Introduction Timely and appropriate accommodations can help employees who experience disabilities stay at work instead of exiting the labor force. Employers can play a critical role in connecting such workers with the accommodations they need. This qualitative study seeks to inform policy makers who want to improve workforce retention outcomes by uncovering factors that affect whether employers provide accommodations to, and ultimately retain, employees with disabilities. Methods We conducted semistructured interviews with a convenience sample of human resources professionals in 14 Arkansas-based employers, yielding detailed information on 50 cases in which an employee developed or disclosed a disability. We analyzed the interviews using a grounded theory approach and compared cases to identify key themes emerging across subgroups of cases. Results Two organization-level factors and four employee-level factors influenced employers' efforts to accommodate and retain employees with disabilities: employer resources; employers' communication with the employee and other stakeholders; employee tenure; employee work performance; active/sedentary nature of employee role; and the severity and type of employees' health conditions. Conclusions Consistent with prior literature, employers with greater access to resources and better ability to communicate generally made greater effort to accommodate and retain employees with disabilities. However, employers in the study did not deploy these resources and processes consistently when making decisions about whether and how to provide accommodations to workers with disabilities; employee-level characteristics affected their actions. Policy makers should consider intervention approaches that reach workers who may be overlooked by employers with scarce resources.

Fixed Points of Competitive Threshold-Linear Networks

Threshold-linear networks (TLNs) are models of neural networks that consist of simple, perceptron-like neurons and exhibit nonlinear dynamics determined by the network's connectivity. The fixed points of a TLN, including both stable and unstable equilibria, play a critical role in shaping its emergent dynamics. In this work, we provide two novel characterizations for the set of fixed points of a competitive TLN: the first is in terms of a simple sign condition, while the second relies on the concept of domination. We apply these results to a special family of TLNs, called combinatorial threshold-linear networks (CTLNs), whose connectivity matrices are defined from directed graphs. This leads us to prove a series of graph rules that enable one to determine fixed points of a CTLN by analyzing the underlying graph. In addition, we study larger networks composed of smaller building block subnetworks and prove several theorems relating the fixed points of the full network to those of its components. Our results provide the foundation for a kind of graphical calculus to infer features of the dynamics from a network's connectivity.

Understanding paediatric patients' attitudes toward obesity and expectations prior to entering a weight management program

Objective

This qualitative study explored attitudes toward weight management and knowledge of healthy, active living among paediatric patients referred to a weight management program. The objective of this study was to determine the emotional state and attitudes of patients entering into a paediatric weight management program.

Methods

Study participants (aged 7 to 17 years old) were recruited during clinic orientation. Semistructured interviews were conducted, audiotaped and transcribed verbatim. Qualitative content analysis generated a thematic coding scheme, identifying concepts and linkages in the data. Study rigour was achieved collaboratively through an audit trail, and data triangulation.

Results

Fifteen patients (median age 11 years) consented to interviews. Three recurring themes emerged: emotions, motivation and learning. A total of nine subthemes were identified. Four key spheres of influence (family, peers, school and health care providers) affected the patient's outlook on obesity positively by providing support or negatively by adversely influencing their emotions and motivation. The level of individual motivation to engage in the weight management program varied. A positive outlook toward learning about obesity from school officials and health care providers emerged.

Conclusions

This study provided insight regarding paediatric attitudes related to entering a weight management program. The negative emotional state and sometimes fear of the program expressed should be considered by the referring physician and by clinicians in weight management programs engaging in their care.

Causes and consequences of gestational diabetes in South Asians living in Canada: results from a prospective cohort study

BACKGROUND

The reasons for the increased risk of gestational diabetes among South Asian women are not well understood. We sought to identify the determinants of gestational diabetes and its impact on newborn health in a prospective birth cohort of South Asian women and their babies.

METHODS

As part of the South Asian Birth Cohort (START) prospective birth cohort study in Ontario, we recruited 1012 South Asian women with singleton pregnancies in the second trimester of pregnancy between July 11, 2011, and Nov. 10, 2015. We collected health information and physical measurements and administered an oral glucose tolerance test. Birth weight and skinfold thickness measurements were obtained from their newborns, and cord blood glucose and insulin levels were measured.

RESULTS

The incidence of gestational diabetes was 36.3% (95% confidence interval [CI] 33.3%-39.3%); the age-standardized rate was 40.7%. Factors associated with gestational diabetes included maternal age (odds ratio [OR] 1.08 [95% CI 1.04-1.12]), family history of diabetes (OR 1.65 [95% CI 1.26-2.17]), prepregnancy weight (OR 1.025 [95% CI 1.01-1.04]) and low diet quality (OR 1.57 [95% CI 1.16-2.12]). Maternal height was protective against gestational diabetes (OR 0.97 [95% CI 0.95-0.99]). The population attributable risk due to prepregnancy body mass index and low diet quality was 37.3%. Compared to newborns of women without gestational diabetes, those of women with gestational diabetes had a significantly higher birth weight (3267 [standard error (SE) 23] g v. 3181 [SE 17] g, p = 0.005), greater skinfold thickness (11.7 [SE 0.1] mm v. 11.2 [SE 0.1] mm, p = 0.007) and lower insulin sensitivity (glucose/insulin ratio 0.092 [SE 0.009] mmol/pmol v. 0.129 [SE 0.006] mmol/pmol, p = 0.001).

INTERPRETATION

The modifiable risk factors of prepregnancy weight and low diet quality accounted for 37% of the population attributable risk of gestational diabetes in our cohort. Intervention studies to lower prepregnancy weight and to prevent gestational diabetes among South Asian women in high-income countries are needed.

Pattern Completion in Symmetric Threshold-Linear Networks

Threshold-linear networks are a common class of firing rate models that describe recurrent interactions among neurons. Unlike their linear counterparts, these networks generically possess multiple stable fixed points (steady states), making them viable candidates for memory encoding and retrieval. In this work, we characterize stable fixed points of general threshold-linear networks with constant external drive and discover constraints on the coexistence of fixed points involving different subsets of active neurons. In the case of symmetric networks, we prove the following antichain property: if a set of neurons [Formula: see text] is the support of a stable fixed point, then no proper subset or superset of [Formula: see text] can support a stable fixed point. Symmetric threshold-linear networks thus appear to be well suited for pattern completion, since the dynamics are guaranteed not to get stuck in a subset or superset of a stored pattern. We also show that for any graph G, we can construct a network whose stable fixed points correspond precisely to the maximal cliques of G. As an application, we design network decoders for place field codes and demonstrate their efficacy for error correction and pattern completion. The proofs of our main results build on the theory of permitted sets in threshold-linear networks, including recently developed connections to classical distance geometry.

Why don't families initiate treatment? A qualitative multicentre study investigating parents' reasons for declining paediatric weight management

BACKGROUND

Many families referred to specialized health services for managing paediatric obesity do not initiate treatment; however, reasons for noninitiation are poorly understood.

OBJECTIVE

To understand parents' reasons for declining tertiary-level health services for paediatric weight management.

METHOD

Interviews were conducted with 18 parents of children (10 to 17 years of age; body mass index ≥85th percentile) who were referred for weight management, but did not initiate treatment at one of three Canadian multidisciplinary weight management clinics. A semi-structured interview guide was used to elicit parents' responses about reasons for noninitiation. Interviews were audio-recorded and transcribed verbatim. Data were managed using NVivo 9 (QSR International, Australia) and analyzed thematically.

RESULTS

Most parents (mean age 44.1 years; range 34 to 55 years) were female (n=16 [89%]), obese (n=12 [66%]) and had a university degree (n=13 [71%]). Parents' reasons for not initiating health services were grouped into five themes: no perceived need for paediatric weight management (eg, perceived children did not have a weight or health problem); no perceived need for further actions (eg, perceived children already had a healthy lifestyle); no intention to initiate recommended care (eg, perceived clinical program was not efficacious); participation barriers (eg, children's lack of motivation); and situational factors (eg, weather).

CONCLUSION

Physicians should not only discuss the need for and value of specialized care for managing paediatric obesity, but also explore parents' intention to initiate treatment and address reasons for noninitiation that are within their control.

Mental health of extremely low birth weight survivors in their 30s

OBJECTIVE

To determine the risk for psychiatric disorders among extremely low birth weight (ELBW) survivors in their early to mid-30s and to determine whether those born small for gestational age or those exposed to a full course of antenatal corticosteroids (ACS) were at particularly high risk.

METHODS

A prospective, longitudinal, population-based cohort of 84 ELBW survivors and 90 normal birth weight (NBW) control participants born in Ontario, Canada from 1977 to 1982 were assessed by interviewers naive to birth weight status using the Mini-International Neuropsychiatric Interview.

RESULTS

ELBW survivors had lower odds of an alcohol or substance use disorder but higher odds of current non-substance-related psychiatric problems (odds ratio [OR] = 2.47; 95% confidence interval [CI], 1.19-5.14). Those born ELBW and SGA exhibited the same patterns with larger effects. ACS-exposed ELBW survivors had even higher odds of any current non-substance-related psychiatric disorder (OR = 4.41; 95% CI, 1.65-11.82), particularly generalized anxiety disorder (OR = 3.42; 95% CI, 1.06-11.06), the generalized type of social phobia (OR = 5.80; 95% CI, 1.20-27.99), and the inattentive subtype of attention-deficit/hyperactivity disorder (OR = 11.45; 95% CI, 2.06-63.50).

CONCLUSIONS

In their early to mid-30s, ELBW survivors were less likely to have alcohol or substance use disorders but may be at greater risk for other psychiatric problems. Those exposed to ACS were at especially high risk and manifested no reduction in alcohol or substance use disorders. ELBW survivors exposed to ACS may be a special group at risk for psychopathology in adulthood.

Treatment of overweight and obesity in children and youth: a systematic review and meta-analysis

BACKGROUND

Childhood obesity is a public health concern. One-third of North American children and youth are overweight or obese. We reviewed the evidence of behavioural and pharmacological weight-management interventions on body mass index (BMI), BMI z-score and the prevalence of overweight and obesity in children and youth.

METHODS

We updated the search of a previous review. We searched 4 databases up to August 2013. We included randomized trials of primary care-relevant behavioural (diet, exercise, lifestyle) and pharmacological (orlistat) interventions for treating overweight and obesity in children and youth aged 2-18 years if 6-month post-baseline data were provided for BMI, BMI z-score or prevalence of overweight and obesity. In addition, we examined secondary health outcomes such as lipid and glucose levels, blood pressure, quality of life and physical fitness. We included any study reporting harms. We performed meta-analyses when possible, and we examined the features of interventions that showed benefits.

RESULTS

Thirty-one studies (29 behavioural, 2 pharmacological and behavioural) were included. Both intervention types showed a significant effect on BMI or BMI z-score in favour of treatment (behavioural: standardized mean difference [SMD] -0.54, 95% confidence interval [CI] -0.73 to -0.36; orlistat plus behavioural: SMD -0.43, 95% CI -0.60 to -0.25). Studies reported no significant difference between groups in the likelihood of reduced prevalence of overweight or overweight and obesity. Pooled estimates for blood pressure and quality of life showed significant benefits in favour of treatment (systolic blood pressure mean difference [MD] -3.42, 95% CI -6.65 to -0.29; diastolic blood pressure MD -3.39, 95% CI -5.17 to -1.60; quality of life MD 2.10, 95% CI 0.60 to 3.60). Gastrointestinal difficulties were more common in youth taking orlistat than in the control group (risk ratio 3.77, 95% CI 2.56 to 5.55). We saw much variability across efficacious interventions.

INTERPRETATION

Low- to moderate-quality evidence suggests behavioural treatments are associated with a medium effect in terms of reduced BMI or BMI z-score compared with a small effect shown by combined pharmacological-behavioural interventions. Future research should evaluate active weight maintenance interventions in adolescents with longer follow-up and examine the effectiveness of combined pharmacological and behavioural interventions.

REGISTRATION

PROSPERO no. CRD42012002754.

Prevention of overweight and obesity in children and youth: a systematic review and meta-analysis

BACKGROUND

One-third of Canadian children are overweight or obese. This problem carries considerable concern for negative impacts on current and future health. Promoting healthy growth and development is critical. This review synthesized evidence on the effectiveness of behavioural interventions for preventing overweight and obesity in children and adolescents.

METHODS

We updated the search of a previous Cochrane review. Five databases were searched up to August 2013. Randomized trials of primary care-relevant behavioural (diet, exercise and lifestyle) interventions for preventing overweight and obesity in healthy normal- or mixed-weight children or youth aged 0-18 years were included if 12-week postbaseline data were provided for body mass index (BMI), BMI z-score, or prevalence of overweight or obesity. Any study reporting harms was included. Meta-analyses were performed if possible. Features of interventions showing significant benefits were examined.

RESULTS

Ninety studies were included, all with mixed-weight populations. Compared with controls, interventions showed a small but significant effect on BMI and BMI z-score (standardized mean difference -0.07, 95% confidence interval [CI] -0.10 to -0.03, I (2) = 74%), a reduction in BMI (mean difference -0.09 kg/m(2), 95% CI -0.16 to -0.03, I (2) = 76%) and a reduced prevalence of overweight and obesity (risk ratio [RR]; RRintervention - RRcontrol 0.94, 95% CI 0.89 to 0.99, I (2) = 0%; number needed to treat 51, 95% CI 29 to 289). Little evidence was available on harms. There was variability across efficacious interventions, although many of the interventions were short-term, involved school-aged children and were delivered in educational settings.

INTERPRETATION

Behavioural prevention interventions are associated with small improvements in weight outcomes in mixed-weight populations of children and adolescents. No intervention strategy consistently produced benefits.

REGISTRATION

PROSPERO no. CRD42012002754.

Combinatorial neural codes from a mathematical coding theory perspective

Shannon's seminal 1948 work gave rise to two distinct areas of research: information theory and mathematical coding theory. While information theory has had a strong influence on theoretical neuroscience, ideas from mathematical coding theory have received considerably less attention. Here we take a new look at combinatorial neural codes from a mathematical coding theory perspective, examining the error correction capabilities of familiar receptive field codes (RF codes). We find, perhaps surprisingly, that the high levels of redundancy present in these codes do not support accurate error correction, although the error-correcting performance of receptive field codes catches up to that of random comparison codes when a small tolerance to error is introduced. However, receptive field codes are good at reflecting distances between represented stimuli, while the random comparison codes are not. We suggest that a compromise in error-correcting capability may be a necessary price to pay for a neural code whose structure serves not only error correction, but must also reflect relationships between stimuli.

Maternal and newborn health profile in a first nations community in Canada

OBJECTIVES

We sought to characterize maternal health profiles and birth outcomes among First Nations people living in Southern Ontario.

METHODS

We performed a retrospective chart review of all 453 women from the Six Nations Reserve, Ontario, who were pregnant between 2005 and 2010. Maternal health behaviours, past medical history, physical measurements, birth outcomes, and newborn characteristics were abstracted. Key maternal and newborn characteristics were compared with those of a cohort of non-First Nations women recruited from nearby Hamilton, Ontario.

RESULTS

The average age of women in the study cohort was 25.1 ± 6.2 (mean ± SD) years, and 75.8% were multiparous. The mean pre-pregnancy BMI was 28.3 ± 6.6 kg/m(2), and the average weight gain in pregnancy was 14.9 ± 8.3 kg. Mean weight gain during pregnancy was inversely associated with pre-pregnancy BMI, and 57.1% of women gained more than the recommended weight. The prevalence of type 2 diabetes or gestational diabetes was 4.7%, hypertension was present before or during pregnancy in 5.6%, and 35% used tobacco during pregnancy. The mean gestational age at delivery was 39.5 ± 1.7 weeks and the mean crude birth weight was 3619 ± 557 g. The main determinants of newborn weight included sex of the newborn, pre-pregnancy BMI, and weight gain during pregnancy. Compared with a contemporary cohort of 622 non-First Nations mothers and newborns, First Nations mothers were, on average, younger (25.1 vs. 32.1 years; P < 0.001), had a higher mean pre-pregnancy BMI (28.3 vs. 26.8 kg/m(2); P < 0.001), and were more likely to use tobacco during pregnancy (35.0% vs. 14.4%; P < 0.001). First Nations newborns had significantly higher mean birth weight (+176 grams) and length (+2.3 cm) than non-First Nations newborns.

CONCLUSION

First Nations mothers from the Six Nations Reserve tended to have a high pre-pregnancy BMI, tended to gain more than the recommended weight during pregnancy, and commonly used tobacco during pregnancy. Programs to prevent overweight/obesity and excess weight gain during pregnancy and to minimize smoking are required among women of child-bearing age in this community.

Are children and adolescents with psychiatric illness at risk for increased future body weight? A systematic review

The aim of this paper was to review the longitudinal relationship between early-onset depression and disruptive behaviour and adult body weight. A systematic review of prospective longitudinal studies was conducted of articles in which (1) initial assessment occurred during childhood or adolescence (<18 y); and (2) the primary outcome reported as body mass index (BMI), overweight (BMI>25-<30 kg/m(2)), obesity (BMI ≥ 30 kg/m(2)), or depression; and (3) validated assessment measures for assessment of depressive symptoms or disruptive behaviour problems were employed. A total number of 16 articles were identified for review. Obese adolescent females are more likely to develop depressive illness in adulthood than their non-obese peers. Conversely, depressed adolescent females, and possibly males, are more likely to become overweight adults than non-depressed adolescents. There are insufficient data addressing future depression risk among overweight, non-obese, adolescents to evaluate the potentially interactive nature of this relationship. Studies to date are consistent in reporting that children with behaviour problems are at increased risk of future overweight, though whether this risk is conferred by conduct symptoms, ADHD symptoms, or both, is less clear. Care providers of children with disruptive behaviour problems and depressed adolescents should monitor weight gain. Among obese adolescent females, mood should be followed.

Global, multicenter, randomized, phase II trial of gemcitabine and gemcitabine plus AGS-1C4D4 in patients with previously untreated, metastatic pancreatic cancer

BACKGROUND

We evaluated AGS-1C4D4, a fully human monoclonal antibody to prostate stem cell antigen (PSCA), with gemcitabine in a randomized, phase II study of metastatic pancreatic cancer.

PATIENTS AND METHODS

Patients with Eastern Cooperative Oncology Group (ECOG) performance status 0/1 and previously untreated, metastatic pancreatic adenocarcinoma were randomly assigned 1:2 to gemcitabine (1000 mg/m(2) weekly seven times, 1 week rest, weekly three times q4weeks) or gemcitabine plus AGS-1C4D4 (48 mg/kg loading dose, then 24 mg/kg q3weeks IV). The primary end point was 6-month survival rate (SR). Archived tumor samples were collected for pre-planned analyses by PSCA expression.

RESULTS

Between April 2009 and May 2010, 196 patients were randomly assigned to gemcitabine (n = 63) or gemcitabine plus AGS-1C4D4 (n = 133). The 6-month SR was 44.4% (95% CI, 31.9-57.5) in the gemcitabine arm and 60.9% (95% CI, 52.1-69.2) in the gemcitabine plus AGS-1C4D4 arm (P = 0.03), while the median survival was 5.5 versus 7.6 months and the response rate was 13.1% versus 21.6% in the two arms, respectively. The 6-month SR was 57.1% in the gemcitabine arm versus 79.5% in the gemcitabine plus AGS-1C4D4 arm among the PSCA-positive subgroup and 31.6% versus 46.2% among the PSCA-negative subgroup.

CONCLUSIONS

This randomized, phase II study achieved its primary end point, demonstrating an improved 6-month SR with addition of AGS-1C4D4 to gemcitabine among patients with previously untreated, metastatic pancreatic adenocarcinoma. ClinicalTrials.gov identifier: NCT00902291.