Showing papers by "Hospital for Sick Children published in 2017"

Analysis of 100,000 human cancer genomes reveals the landscape of tumor mutational burden

Abstract: High tumor mutational burden (TMB) is an emerging biomarker of sensitivity to immune checkpoint inhibitors and has been shown to be more significantly associated with response to PD-1 and PD-L1 blockade immunotherapy than PD-1 or PD-L1 expression, as measured by immunohistochemistry (IHC). The distribution of TMB and the subset of patients with high TMB has not been well characterized in the majority of cancer types. In this study, we compare TMB measured by a targeted comprehensive genomic profiling (CGP) assay to TMB measured by exome sequencing and simulate the expected variance in TMB when sequencing less than the whole exome. We then describe the distribution of TMB across a diverse cohort of 100,000 cancer cases and test for association between somatic alterations and TMB in over 100 tumor types. We demonstrate that measurements of TMB from comprehensive genomic profiling are strongly reflective of measurements from whole exome sequencing and model that below 0.5 Mb the variance in measurement increases significantly. We find that a subset of patients exhibits high TMB across almost all types of cancer, including many rare tumor types, and characterize the relationship between high TMB and microsatellite instability status. We find that TMB increases significantly with age, showing a 2.4-fold difference between age 10 and age 90 years. Finally, we investigate the molecular basis of TMB and identify genes and mutations associated with TMB level. We identify a cluster of somatic mutations in the promoter of the gene PMS2, which occur in 10% of skin cancers and are highly associated with increased TMB. These results show that a CGP assay targeting ~1.1 Mb of coding genome can accurately assess TMB compared with sequencing the whole exome. Using this method, we find that many disease types have a substantial portion of patients with high TMB who might benefit from immunotherapy. Finally, we identify novel, recurrent promoter mutations in PMS2, which may be another example of regulatory mutations contributing to tumorigenesis.

The 2017 international classification of the Ehlers-Danlos syndromes

Abstract: The Ehlers-Danlos syndromes (EDS) are a clinically and genetically heterogeneous group of heritable connective tissue disorders (HCTDs) characterized by joint hypermobility, skin hyperextensibility, and tissue fragility. Over the past two decades, the Villefranche Nosology, which delineated six subtypes, has been widely used as the standard for clinical diagnosis of EDS. For most of these subtypes, mutations had been identified in collagen-encoding genes, or in genes encoding collagen-modifying enzymes. Since its publication in 1998, a whole spectrum of novel EDS subtypes has been described, and mutations have been identified in an array of novel genes. The International EDS Consortium proposes a revised EDS classification, which recognizes 13 subtypes. For each of the subtypes, we propose a set of clinical criteria that are suggestive for the diagnosis. However, in view of the vast genetic heterogeneity and phenotypic variability of the EDS subtypes, and the clinical overlap between EDS subtypes, but also with other HCTDs, the definite diagnosis of all EDS subtypes, except for the hypermobile type, relies on molecular confirmation with identification of (a) causative genetic variant(s). We also revised the clinical criteria for hypermobile EDS in order to allow for a better distinction from other joint hypermobility disorders. To satisfy research needs, we also propose a pathogenetic scheme, that regroups EDS subtypes for which the causative proteins function within the same pathway. We hope that the revised International EDS Classification will serve as a new standard for the diagnosis of EDS and will provide a framework for future research purposes. © 2017 Wiley Periodicals, Inc.

NASPGHAN Clinical Practice Guideline for the Diagnosis and Treatment of Nonalcoholic Fatty Liver Disease in Children: Recommendations from the Expert Committee on NAFLD (ECON) and the North American Society of Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN)

Abstract: Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent chronic liver disease that occurs in the setting of insulin resistance and increased adiposity. It has rapidly evolved into the most common liver disease seen in the pediatric population and is a management challenge for general pediatric practitioners, subspecialists, and for health systems. In this guideline, the expert committee on NAFLD reviewed and summarized the available literature, formulating recommendations to guide screening and clinical care of children with NAFLD.

Quantifying and exploring camouflaging in men and women with autism

Abstract: Autobiographical descriptions and clinician observations suggest that some individuals with autism, particularly females, ‘camouflage’ their social communication difficulties, which may require considerable cognitive effort and lead to increased stress, anxiety and depression Using data from 60 age- and IQ-matched men and women with autism (without intellectual disability), we operationalized camouflaging in adults with autism for the first time as the quantitative discrepancy between the person’s ‘external’ behavioural presentation in social–interpersonal contexts (measured by the Autism Diagnostic Observation Schedule) and the person’s ‘internal’ status (dispositional traits measured by the Autism Spectrum Quotient and social cognitive capability measured by the ‘Reading the Mind in the Eyes’ Test) We found that the operationalized camouflaging measure was not significantly correlated with age or IQ On average, women with autism had higher camouflaging scores than men with autism (Cohen’s d = 098), with substantial variability in both groups Greater camouflaging was associated with more depressive symptoms in men and better signal-detection sensitivity in women with autism The neuroanatomical association with camouflaging score was largely sex/gender-dependent and significant only in women: from reverse inference, the most correlated cognitive terms were about emotion and memory The underlying constructs, measurement, mechanisms, consequences and heterogeneity of camouflaging in autism warrant further investigation

Prevalence of sexual dimorphism in mammalian phenotypic traits

Abstract: The role of sex in biomedical studies has often been overlooked, despite evidence of sexually dimorphic effects in some biological studies. Here, we used high-throughput phenotype data from 14,250 wildtype and 40,192 mutant mice (representing 2,186 knockout lines), analysed for up to 234 traits, and found a large proportion of mammalian traits both in wildtype and mutants are influenced by sex. This result has implications for interpreting disease phenotypes in animal models and humans.

Comparative safety of anti-epileptic drugs during pregnancy: a systematic review and network meta-analysis of congenital malformations and prenatal outcomes

Abstract: Pregnant women with epilepsy frequently experience seizures related to pregnancy complications and are often prescribed anti-epileptic drugs (AEDs) to manage their symptoms. However, less is known about the comparative safety of AED exposure in utero. We aimed to compare the risk of congenital malformations (CMs) and prenatal outcomes of AEDs in infants/children who were exposed to AEDs in utero through a systematic review and Bayesian random-effects network meta-analysis. MEDLINE, EMBASE, and Cochrane CENTRAL were searched from inception to December 15, 2015. Two reviewers independently screened titles/abstracts and full-text papers for experimental and observational studies comparing mono- or poly-therapy AEDs versus control (no AED exposure) or other AEDs, then abstracted data and appraised the risk of bias. The primary outcome was incidence of major CMs, overall and by specific type (cardiac malformations, hypospadias, cleft lip and/or palate, club foot, inguinal hernia, and undescended testes). After screening 5305 titles and abstracts, 642 potentially relevant full-text articles, and 17 studies from scanning reference lists, 96 studies were eligible (n = 58,461 patients). Across all major CMs, many AEDs were associated with higher risk compared to control. For major CMs, ethosuximide (OR, 3.04; 95% CrI, 1.23–7.07), valproate (OR, 2.93; 95% CrI, 2.36–3.69), topiramate (OR, 1.90; 95% CrI, 1.17–2.97), phenobarbital (OR, 1.83; 95% CrI, 1.35–2.47), phenytoin (OR, 1.67; 95% CrI, 1.30–2.17), carbamazepine (OR, 1.37; 95% CrI, 1.10–1.71), and 11 polytherapies were significantly more harmful than control, but lamotrigine (OR, 0.96; 95% CrI, 0.72–1.25) and levetiracetam (OR, 0.72; 95% CrI, 0.43–1.16) were not. The newer generation AEDs, lamotrigine and levetiracetam, were not associated with significant increased risks of CMs compared to control, and were significantly less likely to be associated with children experiencing cardiac malformations than control. However, this does not mean that these agents are not harmful to infants/children exposed in utero. Counselling is advised concerning teratogenic risks when the prescription is written for a woman of childbearing age and before women continue with these agents when considering pregnancy, such as switching from polytherapy to monotherapy with evidence of lower risk and avoiding AEDs, such as valproate, that are consistently associated with CMs. These decisions must be balanced against the need for seizure control. PROSPERO CRD42014008925

Giving Drugs a Second Chance: Overcoming Regulatory and Financial Hurdles in Repurposing Approved Drugs As Cancer Therapeutics

Abstract: The repositioning or "repurposing" of existing therapies for alternative disease indications is an attractive approach that can save significant investments of time and money during drug development. For cancer indications, the primary goal of repurposed therapies is on efficacy, with less restriction on safety due to the immediate need to treat this patient population. This report provides a high-level overview of how drug developers pursuing repurposed assets have previously navigated funding efforts, regulatory affairs, and intellectual property laws to commercialize these "new" medicines in oncology. This article provides insight into funding programs (e.g., government grants and philanthropic organizations) that academic and corporate initiatives can leverage to repurpose drugs for cancer. In addition, we highlight previous examples where secondary uses of existing, Food and Drug Administration- or European Medicines Agency-approved therapies have been predicted in silico and successfully validated in vitro and/or in vivo (i.e., animal models and human clinical trials) for certain oncology indications. Finally, we describe the strategies that the pharmaceutical industry has previously employed to navigate regulatory considerations and successfully commercialize their drug products. These factors must be carefully considered when repurposing existing drugs for cancer to best benefit patients and drug developers alike.

SLAMF7 is critical for phagocytosis of haematopoietic tumour cells via Mac-1 integrin

Abstract: Cancer cells elude anti-tumour immunity through multiple mechanisms, including upregulated expression of ligands for inhibitory immune checkpoint receptors. Phagocytosis by macrophages plays a critical role in cancer control. Therapeutic blockade of signal regulatory protein (SIRP)-α, an inhibitory receptor on macrophages, or of its ligand CD47 expressed on tumour cells, improves tumour cell elimination in vitro and in vivo, suggesting that blockade of the SIRPα-CD47 checkpoint could be useful in treating human cancer. However, the pro-phagocytic receptor(s) responsible for tumour cell phagocytosis is(are) largely unknown. Here we find that macrophages are much more efficient at phagocytosis of haematopoietic tumour cells, compared with non-haematopoietic tumour cells, in response to SIRPα-CD47 blockade. Using a mouse lacking the signalling lymphocytic activation molecule (SLAM) family of homotypic haematopoietic cell-specific receptors, we determined that phagocytosis of haematopoietic tumour cells during SIRPα-CD47 blockade was strictly dependent on SLAM family receptors in vitro and in vivo. In both mouse and human cells, this function required a single SLAM family member, SLAMF7 (also known as CRACC, CS1, CD319), expressed on macrophages and tumour cell targets. In contrast to most SLAM receptor functions, SLAMF7-mediated phagocytosis was independent of signalling lymphocyte activation molecule-associated protein (SAP) adaptors. Instead, it depended on the ability of SLAMF7 to interact with integrin Mac-1 (refs 18, 19, 20) and utilize signals involving immunoreceptor tyrosine-based activation motifs. These findings elucidate the mechanism by which macrophages engulf and destroy haematopoietic tumour cells. They also reveal a novel SAP adaptor-independent function for a SLAM receptor. Lastly, they suggest that patients with tumours expressing SLAMF7 are more likely to respond to SIRPα-CD47 blockade therapy.

Relationship of Echocardiographic Z Scores Adjusted for Body Surface Area to Age, Sex, Race, and Ethnicity: The Pediatric Heart Network Normal Echocardiogram Database.

Abstract: Background—Published nomograms of pediatric echocardiographic measurements are limited by insufficient sample size to assess the effects of age, sex, race, and ethnicity. Variable methodologies hav...

The Ehlers–Danlos syndromes, rare types

Abstract: The Ehlers–Danlos syndromes comprise a clinically and genetically heterogeneous group of heritable connective tissue disorders, which are characterized by joint hypermobility, skin hyperextensibility, and tissue friability. In the Villefranche Nosology, six subtypes were recognized: The classical, hypermobile, vascular, kyphoscoliotic, arthrochalasis, and dermatosparaxis subtypes of EDS. Except for the hypermobile subtype, defects had been identified in fibrillar collagens or in collagen-modifying enzymes. Since 1997, a whole spectrum of novel, clinically overlapping, rare EDS-variants have been delineated and genetic defects have been identified in an array of other extracellular matrix genes. Advances in molecular testing have made it possible to now identify the causative mutation for many patients presenting these phenotypes. The aim of this literature review is to summarize the current knowledge on the rare EDS subtypes and highlight areas for future research. © 2017 Wiley Periodicals, Inc.

Early intervention for children at risk for reading disabilities: The impact of grade at intervention and individual differences on intervention outcomes.

Abstract: Across multiple schools and sites, the impact of grade-at-intervention was evaluated for children at risk or meeting criteria for reading disabilities. A multiple-component reading intervention with demonstrated efficacy was offered to small groups of children in 1st, 2nd, or 3rd grade. In a quasi-experimental design, 172 children received the Triple-Focus Program (PHAST + RAVE-O), and 47 were control participants. Change during intervention and 1–3 years later (6–8 testing points), and the influence of individual differences in predicting outcomes, were assessed using reading and reading-related repeated measures. Intervention children out-performed control children at posttest on all 14 outcomes, with average effect sizes (Cohen’s d) on standardized measures of .80 and on experimental measures of 1.69. On foundational word reading skills (standardized measures), children who received intervention earlier, in 1st and 2nd grade, made gains relative to controls almost twice that of children receiving intervention in 3rd grade. At follow-up, the advantage of 1st grade intervention was even clearer: First graders continued to grow at faster rates over the follow-up years than 2nd graders on 6 of 8 reading outcomes. For some outcomes with metalinguistic demands beyond the phonological, however, a posttest advantage was revealed for 2nd Grade Triple participants and for 3rd Grade Triple participants relative to controls. Estimated IQ predicted growth during intervention on 7 of 8 outcomes. Growth during follow-up was predicted by vocabulary and visual sequential memory. These findings provide evidence on the importance of early intensive evidence-based intervention for reading problems in the primary grades. (PsycINFO Database Record (c) 2017 APA, all rights reserved)

Structures of closed and open states of a voltage-gated sodium channel.

Abstract: Bacterial voltage-gated sodium channels (BacNavs) serve as models of their vertebrate counterparts. BacNavs contain conserved voltage-sensing and pore-forming domains, but they are homotetramers of four identical subunits, rather than pseudotetramers of four homologous domains. Here, we present structures of two NaVAb mutants that capture tightly closed and open states at a resolution of 2.8-3.2 A. Introduction of two humanizing mutations in the S6 segment (NaVAb/FY: T206F and V213Y) generates a persistently closed form of the activation gate in which the intracellular ends of the four S6 segments are drawn tightly together to block ion permeation completely. This construct also revealed the complete structure of the four-helix bundle that forms the C-terminal domain. In contrast, truncation of the C-terminal 40 residues in NavAb/1-226 captures the activation gate in an open conformation, revealing the open state of a BacNav with intact voltage sensors. Comparing these structures illustrates the full range of motion of the activation gate, from closed with its orifice fully occluded to open with an orifice of ∼10 A. Molecular dynamics and free-energy simulations confirm designation of NaVAb/1-226 as an open state that allows permeation of hydrated Na+, and these results also support a hydrophobic gating mechanism for control of ion permeation. These two structures allow completion of a closed-open-inactivated conformational cycle in a single voltage-gated sodium channel and give insight into the structural basis for state-dependent binding of sodium channel-blocking drugs.

A large scale hearing loss screen reveals an extensive unexplored genetic landscape for auditory dysfunction.

Abstract: The developmental and physiological complexity of the auditory system is likely reflected in the underlying set of genes involved in auditory function. In humans, over 150 non-syndromic loci have been identified, and there are more than 400 human genetic syndromes with a hearing loss component. Over 100 non-syndromic hearing loss genes have been identified in mouse and human, but we remain ignorant of the full extent of the genetic landscape involved in auditory dysfunction. As part of the International Mouse Phenotyping Consortium, we undertook a hearing loss screen in a cohort of 3006 mouse knockout strains. In total, we identify 67 candidate hearing loss genes. We detect known hearing loss genes, but the vast majority, 52, of the candidate genes were novel. Our analysis reveals a large and unexplored genetic landscape involved with auditory function.The full extent of the genetic basis for hearing impairment is unknown. Here, as part of the International Mouse Phenotyping Consortium, the authors perform a hearing loss screen in 3006 mouse knockout strains and identify 52 new candidate genes for genetic hearing loss.

Implementation and preliminary effectiveness of a real-time pain management smartphone app for adolescents with cancer: A multicenter pilot clinical study.

Abstract: Background Pain in adolescents with cancer (12–18 years) is common and negatively impacts health-related quality of life (HRQL). The Pain Squad+ smartphone app, which provides adolescents with real-time pain self-management support, was developed to address this issue. This study evaluated the implementation of the app to inform a future randomized controlled trial (RCT) and obtain treatment effect estimates for pain intensity, pain interference, HRQL, and self-efficacy. Procedure A one-group baseline/poststudy design with 40 adolescents recruited from two pediatric tertiary care centers was used. Baseline questionnaires were completed and adolescents used the app at least twice daily for 28 days, receiving algorithm-informed self-management advice depending on their reported pain. A nurse received alerts in response to sustained pain and contacted adolescents to assist in pain care. Poststudy questionnaires were completed. Descriptive analyses, with exploratory inferential testing conducted on health outcome data, were used to address study aims. Results Most (40/52; 77%) eligible adolescents participated. Two participants withdrew participation. Intervention fidelity was impacted by technical difficulties (occurring for 15% of participants) and a prolonged time for nurse contact in the event of sustained pain. Adherence to pain reporting was 68.8 ± 38.1%. Outcome measure completion rates were high and the intervention was acceptable to participants. Trends in improvements in pain intensity, pain interference, and HRQL were significant, with effect sizes of 0.23–0.67. Conclusions Implementation of Pain Squad+ is feasible and the app appears to improve pain-related outcomes for adolescents with cancer. A multicenter RCT will be undertaken to examine app effectiveness.

Guidelines for the management of postoperative obstructive symptoms in children with Hirschsprung disease.

Abstract: Although most children with Hirschsprung disease ultimately do well, many experience a variety of ongoing problems after pull-through surgery. The most common include obstructive symptoms, soiling, enterocolitis and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative obstructive symptoms in children with Hirschsprung disease. The American Pediatric Surgical Association Board of Governors established a Hirschsprung Disease Interest Group. Group discussions, literature review and expert consensus were then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with obstructive symptoms following pull-through for Hirschsprung disease. Causes of obstructive symptoms post-pull-through include mechanical obstruction; persistent or acquired aganglionosis, hypoganglionosis, or transition zone pull-through; internal sphincter achalasia; disordered motility in the proximal intestine that contains ganglion cells; or functional megacolon caused by stool-holding behavior. An algorithm for the diagnosis and management of obstructive symptoms after a pull-through for Hirschsprung disease is presented. A stepwise, logical approach to the diagnosis and management of patients experiencing obstructive symptoms following pull-through for Hirschsprung disease can facilitate treatment. Level of evidence V.

Epigenetics of Autism Spectrum Disorder.

Abstract: Autism spectrum disorder (ASD), one of the most common childhood neurodevelopmental disorders (NDDs), is diagnosed in 1 of every 68 children ASD is incredibly heterogeneous both clinically and aetiologically The etiopathogenesis of ASD is known to be complex, including genetic, environmental and epigenetic factors Normal epigenetic marks modifiable by both genetics and environmental exposures can result in epigenetic alterations that disrupt the regulation of gene expression, negatively impacting biological pathways important for brain development In this chapter we aim to summarize some of the important literature that supports a role for epigenetics in the underlying molecular mechanism of ASD We provide evidence from work in genetics, from environmental exposures and finally from more recent studies aimed at directly determining ASD-specific epigenetic patterns, focusing mainly on DNA methylation (DNAm) Finally, we briefly discuss some of the implications of current research on potential epigenetic targets for therapeutics and novel avenues for future work

2016 American College of Rheumatology/European League Against Rheumatism Criteria for Minimal, Moderate, and Major Clinical Response in Juvenile Dermatomyositis: An International Myositis Assessment and Clinical Studies Group/Paediatric Rheumatology International Trials Organisation Collaborative Initiative.

Abstract: To develop response criteria for adult dermatomyositis (DM) and polymyositis (PM). Expert surveys, logistic regression, and conjoint analysis were used to develop 287 definitions using core set measures. Myositis experts rated greater improvement among multiple pairwise scenarios in conjoint analysis surveys, where different levels of improvement in 2 core set measures were presented. The PAPRIKA (Potentially All Pairwise Rankings of All Possible Alternatives) method determined the relative weights of core set measures and conjoint analysis definitions. The performance characteristics of the definitions were evaluated on patient profiles using expert consensus (gold standard) and were validated using data from a clinical trial. The nominal group technique was used to reach consensus. Consensus was reached for a conjoint analysis-based continuous model using absolute per cent change in core set measures (physician, patient, and extramuscular global activity, muscle strength, Health Assessment Questionnaire, and muscle enzyme levels). A total improvement score (range 0-100), determined by summing scores for each core set measure, was based on improvement in and relative weight of each core set measure. Thresholds for minimal, moderate, and major improvement were ≥20, ≥40, and ≥60 points in the total improvement score. The same criteria were chosen for juvenile DM, with different improvement thresholds. Sensitivity and specificity in DM/PM patient cohorts were 85% and 92%, 90% and 96%, and 92% and 98% for minimal, moderate, and major improvement, respectively. Definitions were validated in the clinical trial analysis for differentiating the physician rating of improvement (p<0.001). The response criteria for adult DM/PM consisted of the conjoint analysis model based on absolute per cent change in 6 core set measures, with thresholds for minimal, moderate, and major improvement.

The Genetic Landscape of Renal Complications in Type 1 Diabetes.

Abstract: Diabetes is the leading cause of ESRD. Despite evidence for a substantial heritability of diabetic kidney disease, efforts to identify genetic susceptibility variants have had limited success. We extended previous efforts in three dimensions, examining a more comprehensive set of genetic variants in larger numbers of subjects with type 1 diabetes characterized for a wider range of cross-sectional diabetic kidney disease phenotypes. In 2843 subjects, we estimated that the heritability of diabetic kidney disease was 35% (P=6.4×10-3). Genome-wide association analysis and replication in 12,540 individuals identified no single variants reaching stringent levels of significance and, despite excellent power, provided little independent confirmation of previously published associated variants. Whole-exome sequencing in 997 subjects failed to identify any large-effect coding alleles of lower frequency influencing the risk of diabetic kidney disease. However, sets of alleles increasing body mass index (P=2.2×10-5) and the risk of type 2 diabetes (P=6.1×10-4) associated with the risk of diabetic kidney disease. We also found genome-wide genetic correlation between diabetic kidney disease and failure at smoking cessation (P=1.1×10-4). Pathway analysis implicated ascorbate and aldarate metabolism (P=9.0×10-6), and pentose and glucuronate interconversions (P=3.0×10-6) in pathogenesis of diabetic kidney disease. These data provide further evidence for the role of genetic factors influencing diabetic kidney disease in those with type 1 diabetes and highlight some key pathways that may be responsible. Altogether these results reveal important biology behind the major cause of kidney disease.

Orkambi® and amplifier co‐therapy improves function from a rare CFTR mutation in gene‐edited cells and patient tissue

Abstract: The combination therapy of lumacaftor and ivacaftor (Orkambi ® ) is approved for patients bearing the major cystic fibrosis (CF) mutation: ΔF508 . It has been predicted that Orkambi ® could treat patients with rarer mutations of similar “theratype”; however, a standardized approach confirming efficacy in these cohorts has not been reported. Here, we demonstrate that patients bearing the rare mutation: c.3700 A>G, causing protein misprocessing and altered channel function—similar to ΔF508‐CFTR, are unlikely to yield a robust Orkambi ® response. While in silico and biochemical studies confirmed that this mutation could be corrected and potentiated by lumacaftor and ivacaftor, respectively, this combination led to a minor in vitro response in patient‐derived tissue. A CRISPR/Cas9‐edited bronchial epithelial cell line bearing this mutation enabled studies showing that an “amplifier” compound, effective in increasing the levels of immature CFTR protein, augmented the Orkambi ® response. Importantly, this “amplifier” effect was recapitulated in patient‐derived nasal cultures—providing the first evidence for its efficacy in augmenting Orkambi ® in tissues harboring a rare CF‐causing mutation. We propose that this multi‐disciplinary approach, including creation of CRISPR/Cas9‐edited cells to profile modulators together with validation using primary tissue, will facilitate therapy development for patients with rare CF mutations.

The role of same-sex mentorship and organizational support in encouraging women to pursue surgery.

Abstract: Introduction While women represent approximately half of all medical students, only 38% of general surgery residents are women. The objective of this study is to explore how access to mentors and organizational support affects career choices. Methods In June of 2016, a survey was sent to medical students at a single institution (n = 472). Questions utilized a 5-point Likert scale. A two-sample t-test was used to evaluate data. Results A total of 160 students participated in the survey. Among MS1/MS2 students, women were more likely to rank same-sex role models as a positive influence (mean 3.1 vs. 2.4; p Conclusion Exposure to same-sex mentors was highly rated among female participants. These findings encourage the creation of national mentorship programs. Early involvement in organizations can positively influence career choice. Addressing gaps in mentorship opportunities and widening accessibility to national organizations are important in reducing barriers.

Late (≥ 7 days) inhalation corticosteroids to reduce bronchopulmonary dysplasia in preterm infants.

Abstract: Background Bronchopulmonary dysplasia (BPD), defined as oxygen dependence at 36 weeks postmenstrual age (PMA), remains an important complication of prematurity. Pulmonary inflammation plays a central role in the pathogenesis of BPD. Attenuating pulmonary inflammation with postnatal systemic corticosteroids reduces the incidence of BPD in preterm infants but may be associated with an increased risk of adverse neurodevelopmental outcomes. Local administration of corticosteroids via inhalation might be an effective and safe alternative. Objectives To determine if administration of inhalation corticosteroids after the first week of life until 36 weeks PMA to preterm infants at high risk of developing BPD is effective and safe in reducing the incidence of death and BPD as separate or combined outcomes. Search methods We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2017, Issue 4), MEDLINE via PubMed (1966 to 19 May 2017), Embase (1980 to 19 May 2017), and CINAHL (1982 to 19 May 2017). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. Selection criteria We included randomised controlled trials comparing inhalation corticosteroids, started ≥ 7 days postnatal age (PNA) but before 36 weeks PMA, to placebo in ventilated and non-ventilated infants at risk of BPD. We excluded trials investigating systemic corticosteroids versus inhalation corticosteroids. Data collection and analysis We collected data on participant characteristics, trial methodology, and inhalation regimens. The primary outcome was death or BPD at 36 weeks PMA. Secondary outcomes were the combined outcome death or BPD at 28 days PNA, the seperate outcomes of death and BPD at both 28 days PNA, and at 36 weeks PMA, and short-term respiratory outcomes, such as failure to extubate; total days of mechanical ventilation and oxygen use; and the need for systemic corticosteroids. We contacted the original trialists to verify the validity of extracted data and to provide missing data. We analysed all data using Review Manager 5. When possible, we performed meta-analysis using typical risk ratio (RR) for dichotomous outcomes and weighted mean difference (WMD) for continuous outcomes along with their 95% confidence intervals (CI). We analysed ventilated and non-ventilated participants separately. We used the GRADE approach to assess the quality of the evidence. Main results We included eight trials randomising 232 preterm infants in this review. Inhalation corticosteroids did not reduce the separate or combined outcomes of death or BPD. The meta-analyses of the studies showed a reduced risk in favor of inhalation steroids regarding failure to extubate at seven days (typical RR (TRR) 0.80, 95% CI 0.66 to 0.98; 5 studies, 79 infants) and at the latest reported time point after treatment onset (TRR 0.60, 95% CI 0.45 to 0.80; 6 studies, 90 infants). However, both analyses showed increased statistical heterogeneity (I2 statistic 73% and 86%, respectively). Furthermore, inhalation steroids did not impact total duration of mechanical ventilation or oxygen dependency. There was a trend toward a reduction in the use of systemic corticosteroids in infants receiving inhalation corticosteroids (TRR 0.51, 95% CI 0.26 to 1.00; 4 studies, 74 infants; very low-quality evidence). There was a paucity of data on short- and long-term adverse effects. Our results should be interpreted with caution because the total number of randomised participants is relatively small, and most trials differed considerably in participant characteristics, inhalation therapy, and outcome definitions. Authors' conclusions Based on the results of the currently available evidence, inhalation corticosteroids initiated at ≥ 7 days of life for preterm infants at high risk of developing BPD cannot be recommended at this point in time. More and larger randomised, placebo-controlled trials are needed to establish the efficacy and safety of inhalation corticosteroids.

Strategies to Improve Stroke Care Services in Low- and Middle-Income Countries: A Systematic Review.

Abstract: Background: The burden of stroke in low- and middle-income countries (LMICs) is large and increasing, challenging the already stretched health-care services. Aims and Objectives: To determine the quality of existing stroke-care services in LMICs and to highlight indigenous, inexpensive, evidence-based implementable strategies being used in stroke-care. Methods: A detailed literature search was undertaken using PubMed and Google scholar from January 1966 to October 2015 using a range of search terms. Of 921 publications, 373 papers were shortlisted and 31 articles on existing stroke-services were included. Results: We identified efficient models of ambulance transport and pre-notification. Stroke Units (SU) are available in some countries, but are relatively sparse and mostly provided by the private sector. Very few patients were thrombolysed; this could be increased with telemedicine and governmental subsidies. Adherence to secondary preventive drugs is affected by limited availability and affordability, emphasizing the importance of primary prevention. Training of paramedics, care-givers and nurses in post-stroke care is feasible. Conclusion: In this systematic review, we found several reports on evidence-based implementable stroke services in LMICs. Some strategies are economic, feasible and reproducible but remain untested. Data on their outcomes and sustainability is limited. Further research on implementation of locally and regionally adapted stroke-services and cost-effective secondary prevention programs should be a priority.

Pulmonary vein stenosis of ex-premature infants with pulmonary hypertension and bronchopulmonary dysplasia, epidemiology, and survival from a multicenter cohort.

Abstract: Background Pulmonary vein stenosis is emerging as an important clinical problem in ex-premature infants. Methods We sought to describe the epidemiology of pulmonary vein stenosis affecting ex-premature infants by a multicenter retrospective cohort study of patients from seven children's hospitals diagnosed between 2000-2014. Results We identified 39 ex-premature patients (26 males, median gestational age 28 weeks range 22-36 weeks, birth weight 1.1 kg range 433-2645–g) with pulmonary vein stenosis. Median age at diagnosis was 6.5 months (1 month-6 years). Presentation with pulmonary hypertension occurred in 26/39 (67%) and 29/39 (74%) had bronchopulmonary dysplasia, 15 (39%) were born of twin pregnancies with unaffected twin siblings. A median of 5 (range 1-25) echocardiograms was performed prior to diagnosis. The diagnosis was made using echocardiography in 22/39 (56%), by multi-detector contrast computed tomography scan (CT) in 8/39 (21%), cardiac catheterization in 6/39 (15%) patients, magnetic resonance imaging in 3/39 (8%). Freedom from death or re-stenosis was 73% at 1-year, 55% at 2, 5, and 10 years. Factors associated with shorter survival or re-stenosis were stenosis of ≥3 pulmonary veins (P < 0.01), bilateral pulmonary vein stenosis (P < 0.01) small for gestational age (P = 0.05), aged <6 months at diagnosis (P < 0.01). Conclusion Pulmonary vein stenosis of ex-premature infants is a complex problem with poor survival, delayed diagnosis, and unsatisfactory treatment. The lack of concordance in twins suggests epigenetic or environmental factors may play a role in the development of pulmonary vein stenosis. In ex-premature infants with pulmonary hypertension and bronchopulmonary dysplasia a focused echocardiographic assessment of the pulmonary veins is required with further imaging if the echocardiogram is inconclusive.

Microbial glycoside hydrolases as antibiofilm agents with cross-kingdom activity.

Abstract: Galactosaminogalactan and Pel are cationic heteropolysaccharides produced by the opportunistic pathogens Aspergillus fumigatus and Pseudomonas aeruginosa, respectively. These exopolysaccharides both contain 1,4-linked N-acetyl-d-galactosamine and play an important role in biofilm formation by these organisms. Proteins containing glycoside hydrolase domains have recently been identified within the biosynthetic pathway of each exopolysaccharide. Recombinant hydrolase domains from these proteins (Sph3h from A. fumigatus and PelAh from P. aeruginosa) were found to degrade their respective polysaccharides in vitro. We therefore hypothesized that these glycoside hydrolases could exhibit antibiofilm activity and, further, given the chemical similarity between galactosaminogalactan and Pel, that they might display cross-species activity. Treatment of A. fumigatus with Sph3h disrupted A. fumigatus biofilms with an EC50 of 0.4 nM. PelAh treatment also disrupted preformed A. fumigatus biofilms with EC50 values similar to those obtained for Sph3h In contrast, Sph3h was unable to disrupt P. aeruginosa Pel-based biofilms, despite being able to bind to the exopolysaccharide. Treatment of A. fumigatus hyphae with either Sph3h or PelAh significantly enhanced the activity of the antifungals posaconazole, amphotericin B, and caspofungin, likely through increasing antifungal penetration of hyphae. Both enzymes were noncytotoxic and protected A549 pulmonary epithelial cells from A. fumigatus-induced cell damage for up to 24 h. Intratracheal administration of Sph3h was well tolerated and reduced pulmonary fungal burden in a neutropenic mouse model of invasive aspergillosis. These findings suggest that glycoside hydrolases can exhibit activity against diverse microorganisms and may be useful as therapeutic agents by degrading biofilms and attenuating virulence.

Stand Up and Be Counted: Measuring and Mapping the Rheumatology Workforce in Canada.

Abstract: Objective. To characterize the practicing rheumatologist workforce, the Canadian Rheumatology Association (CRA) launched the Stand Up and Be Counted workforce survey in 2015. Methods. The survey was distributed electronically to 695 individuals, of whom 519 were expected to be practicing rheumatologists. Demographic and practice information were elicited. We estimated the number of full-time equivalent rheumatologists per 75,000 population from the median proportion of time devoted to clinical practice multiplied by provincial rheumatologist numbers from the Canadian Medical Association. Results. The response rate was 68% (355/519) of expected practicing rheumatologists (304 were in adult practice, and 51 pediatric). The median age was 50 years, and one-third planned to retire within the next 5–10 years. The majority (81%) were university-affiliated. Rheumatologists spent a median of 70% of their time in clinical practice, holding 6 half-day clinics weekly, with 10 new consultations and 45 followups seen per week. Work characteristics varied by type of rheumatologist (adult or pediatric) and by practice setting (community- or university-based). We estimated between 0 and 0.8 full-time rheumatologists per 75,000 population in each province. This represents a deficit of 1 to 77 full-time rheumatologists per province/territory to meet the CRA recommendation of 1 rheumatologist per 75,000 population, depending on the province/territory. Conclusion. Our results highlight a current shortage of rheumatologists in Canada that may worsen in the next 10 years because one-third of the workforce plans to retire. Efforts to encourage trainees to enter rheumatology and strategies to support retention are critical to address the shortage.

The Genetic Landscape of Renal Complications in Type 1 Diabetes

Abstract: Diabetes is the leading cause of ESRD. Despite evidence for a substantial heritability of diabetic kidney disease, efforts to identify genetic susceptibility variants have had limited success. We extended previous efforts in three dimensions, examining a more comprehensive set of genetic variants in larger numbers of subjects with type 1 diabetes characterized for a wider range of cross-sectional diabetic kidney disease phenotypes. In 2843 subjects, we estimated that the heritability of diabetic kidney disease was 35% (P=6.4×10-3). Genome-wide association analysis and replication in 12,540 individuals identified no single variants reaching stringent levels of significance and, despite excellent power, provided little independent confirmation of previously published associated variants. Whole-exome sequencing in 997 subjects failed to identify any large-effect coding alleles of lower frequency influencing the risk of diabetic kidney disease. However, sets of alleles increasing body mass index (P=2.2×10-5) and the risk of type 2 diabetes (P=6.1×10-4) associated with the risk of diabetic kidney disease. We also found genome-wide genetic correlation between diabetic kidney disease and failure at smoking cessation (P=1.1×10-4). Pathway analysis implicated ascorbate and aldarate metabolism (P=9.0×10-6), and pentose and glucuronate interconversions (P=3.0×10-6) in pathogenesis of diabetic kidney disease. These data provide further evidence for the role of genetic factors influencing diabetic kidney disease in those with type 1 diabetes and highlight some key pathways that may be responsible. Altogether these results reveal important biology behind the major cause of kidney disease.

Parents perspectives on whole genome sequencing for their children: qualified enthusiasm?

Abstract: Objective To better understand the consequences of returning whole genome sequencing (WGS) results in paediatrics and facilitate its evidence-based clinical implementation, we studied parents9 experiences with WGS and their preferences for the return of adult-onset secondary variants (SVs)—medically actionable genomic variants unrelated to their child9s current medical condition that predict adult-onset disease. Methods We conducted qualitative interviews with parents whose children were undergoing WGS as part of the SickKids Genome Clinic, a research project that studies the impact of clinical WGS on patients, families, and the healthcare system. Interviews probed parents9 experience with and motivation for WGS as well as their preferences related to SVs. Interviews were analysed thematically. Results Of 83 invited, 23 parents from 18 families participated. These parents supported WGS as a diagnostic test, perceiving clear intrinsic and instrumental value. However, many parents were ambivalent about receiving SVs, conveying a sense of self-imposed obligation to take on the ‘weight’ of knowing their child9s SVs, however unpleasant. Some parents chose to learn about adult-onset SVs for their child but not for themselves. Conclusions Despite general enthusiasm for WGS as a diagnostic test, many parents felt a duty to learn adult-onset SVs. Analogous to ‘inflicted insight’, we call this phenomenon ‘inflicted ought’. Importantly, not all parents of children undergoing WGS view the best interests of their child in relational terms, thereby challenging an underlying justification for current ACMG guidelines for reporting incidental secondary findings from whole exome and WGS.

Communicating with children and families about obesity and weight-related topics: a scoping review of best practices

Abstract: SummaryBackground Healthcare professionals have called for direction on how best to communicate about weight-related topics with children and families. Established scoping review methodology was used to answer the question: ‘How can healthcare professionals best communicate with children and their families about obesity and weight-related topics?’ Methods We searched four scientific databases, two grey literature repositories and 14 key journals (2005–2016). Inclusion criteria were (i) children up to and including 18 years of age and/or their parents; (ii) communication about healthy weight, overweight, obesity or healthy/active living; and (iii) healthcare setting. Results Thirty-two articles were included. Evidence-based best practices were largely absent from the literature, although the following guiding principles were identified: (i) include all stakeholders in discussions; (ii) raise the topic of weight and health early and regularly; (iii) use strengths-based language emphasizing health over weight; (iv) use collaborative goal-setting to engage children and parents and (v) augment discussions with appropriate tools and resources. Guidance on how to implement these principles and how to negotiate relevant contextual factors (e.g. age, culture and disability) is still needed. Conclusion Despite agreement on a number of guiding principles, evidence-based weight-related communication best practices are lacking. Rigorous, empirical evaluations of communication approaches are urgently required, especially those that include children's perspectives.

Standard versus biofilm antimicrobial susceptibility testing to guide antibiotic therapy in cystic fibrosis

Abstract: Background The antibiotics used to treat pulmonary infections in people with cystic fibrosis are typically chosen based on the results of antimicrobial susceptibility testing performed on bacteria traditionally grown in a planktonic mode (grown in a liquid). However, there is considerable evidence to suggest that Pseudomonas aeruginosa actually grows in a biofilm (or slime layer) in the airways of people with cystic fibrosis with chronic pulmonary infections. Therefore, choosing antibiotics based on biofilm rather than conventional antimicrobial susceptibility testing could potentially improve response to treatment of Pseudomonas aeruginosa in people with cystic fibrosis. This is an update of a previously published Cochrane Review. Objectives To compare biofilm antimicrobial susceptibility testing-driven therapy to conventional antimicrobial susceptibility testing-driven therapy in the treatment of Pseudomonas aeruginosa infection in people with cystic fibrosis. Search methods We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. Most recent search: 19 June 2017. We also searched two ongoing trials registries and the reference lists of relevant articles and reviews. Most recent searches: 24 August 2017 and 05 September 2017. Selection criteria Randomized controlled trials of antibiotic therapy based on biofilm antimicrobial susceptibility testing compared to antibiotic therapy based on conventional antimicrobial susceptibility testing in the treatment of Pseudomonas aeruginosa pulmonary infection in people with cystic fibrosis. Data collection and analysis Both authors independently selected trials, assessed their risk of bias and extracted data from eligible trials. Additionally, the review authors contacted the trial investigators to obtain further information. The quality of the evidence was assessed using the GRADE criteria. Main results The searches identified two multicentre, randomized, double-blind controlled clinical trials eligible for inclusion in the review with a total of 78 participants (adults and children); one trial was done in people who were clinically stable, the other in people experiencing pulmonary exacerbations. These trials prospectively assessed whether the use of biofilm antimicrobial susceptibility testing improved microbiological and clinical outcomes in participants with cystic fibrosis who were infected with Pseudomonas aeruginosa. The primary outcome was the change in sputum Pseudomonas aeruginosa density from the beginning to the end of antibiotic therapy. Although the intervention was shown to be safe, the data from these two trials did not provide evidence that biofilm susceptibility testing was superior to conventional susceptibility testing either in terms of microbiological or lung function outcomes. One of the trials also measured risk and time to subsequent exacerbation as well as quality of life measures and did not demonstrate any difference between groups in these outcomes. Both trials had an overall low risk of bias and the quality of the evidence using GRADE criteria was deemed to be moderate to high for the outcomes selected. Authors' conclusions The current evidence is insufficient to recommend choosing antibiotics based on biofilm antimicrobial susceptibility testing rather than conventional antimicrobial susceptibility testing in the treatment of Pseudomonas aeruginosa pulmonary infections in people with cystic fibrosis. Biofilm antimicrobial susceptibility testing may be more appropriate in the development of newer, more effective formulations of drugs which can then be tested in clinical trials.