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Key points Ketone bodies are proposed to represent an alternative fuel source driving energy production, particularly during exercise. Biologically, the extent to which mitochondria utilize ketone bodies compared to other substrates remains unknown. We demonstratein vitrothat maximal mitochondrial respiration supported by ketone bodies is low when compared to carbohydrate-derived substrates in the left ventricle and red gastrocnemius muscle from rodents, and in human skeletal muscle. When considering intramuscular concentrations of ketone bodies and the presence of other carbohydrate and lipid substrates, biological rates of mitochondrial respiration supported by ketone bodies are predicted to be minimal. At the mitochondrial level, it is therefore unlikely that ketone bodies are an important source for energy production in cardiac and skeletal muscle, particularly when other substrates are readily available. Ketone bodies (KB) have recently gained popularity as an alternative fuel source to support mitochondrial oxidative phosphorylation and enhance exercise performance. However, given the low activity of ketolytic enzymes and potential inhibition from carbohydrate oxidation, it remains unknown if KBs can contribute to energy production. We therefore determined the ability of KBs (sodiumdl-beta-hydroxybutyrate, beta-HB; lithium acetoacetate, AcAc) to stimulatein vitromitochondrial respiration in the left ventricle (LV) and red gastrocnemius (RG) of rats, and in human vastus lateralis. Compared to pyruvate, the ability of KBs to maximally drive respiration was low in isolated mitochondria and permeabilized fibres (PmFb) from the LV (similar to 30-35% of pyruvate), RG (similar to 10-30%), and human vastus lateralis (similar to 2-10%). In PmFb, the concentration of KBs required to half-maximally drive respiration (LV: 889 mu m beta-HB, 801 mu mAcAc; RG: 782 mu m beta-HB, 267 mu mAcAc) were greater than KB content representative of the muscle microenvironment (similar to 100 mu m). This would predict low rates (similar to 1-4% of pyruvate) of biological KB-supported respiration in the LV (8-14 pmol s(-1) mg(-1)) and RG (3-6 pmol s(-1) mg(-1)) at rest and following exercise. Moreover, KBs did not increase respiration in the presence of saturating pyruvate, submaximal pyruvate (100 mu m) reduced the ability of physiological beta-HB to drive respiration, and addition of other intracellular substrates (succinate + palmitoylcarnitine) decreased maximal KB-supported respiration. As a result, product inhibition is likely to limit KB oxidation. Altogether, the ability of KBs to drive mitochondrial respiration is minimal and they are likely to be outcompeted by other substrates, compromising their use as an important energy source.

Patients often start treatment to reduce fracture risk because of a bone mineral density T-score consistent with osteoporosis (≤ -2.5). Others with a T-score above -2.5 may be treated when there is a history of fragility fracture or when a fracture risk algorithm categorizes them as having a high risk for fracture. It is common to initiate therapy with a generic oral bisphosphonate, unless contraindicated, and continue therapy if the patient is responding as assessed by stability or an increase in bone mineral density. However, some patients may respond well to an oral bisphosphonate, yet remain with an unacceptably high risk for fracture. Recognition of this occurrence has led to the development of an alternative strategy: treat-to-target. This involves identifying a biological marker (treatment target) that represents an acceptable fracture risk and then initiating treatment with an agent likely to reach this target. If the patient is on a path to reaching the target with initial therapy, treatment is continued. If it appears the target will not be reached with initial therapy, treatment is changed to an agent more likely to achieve the goal.

International audience; Fiber tractography (FT) using diffusion magnetic resonance imaging (dMRI) is widely used for investigating microstructural properties of white matter (WM) fiber-bundles and for mapping structural connections of the human brain. While studying the architectural configuration of the brain's circuitry with FT is not without controversy, recent progress in acquisition, processing, modeling, analysis, and visualization of dMRI data pushes forward the reliability in reconstructing WM pathways. Despite being aware of the well-known pitfalls in analyzing dMRI data and several other limitations of FT discussed in recent literature, we present the superoanterior fasciculus (SAF), a novel bilateral fiber tract in the frontal region of the human brain that-to the best of our knowledge-has not been documented. The SAF has a similar shape to the anterior part of the cingulum bundle, but it is located more frontally. To minimize the possibility that these FT findings are based on acquisition or processing artifacts, different dMRI data sets and processing pipelines have been used to describe the SAF. Furthermore, we evaluated the configuration of the SAF with complementary methods, such as polarized light imaging (PLI) and human brain dissections. The FT results of the SAF demonstrate a long pathway, consistent across individuals, while the human dissections indicate fiber pathways connecting the postero-dorsal with the antero-dorsal cortices of the frontal lobe.

Background: The contemporary prognostic value of the physical examination— beyond traditional risk factors including natriuretic peptides, risk scores, and symptoms—in heart failure (HF) with reduced ejection fraction is unknown. We aimed to determine the association between physical signs of congestion at baseline and during study follow-up with quality of life and clinical outcomes and to assess the treatment effects of sacubitril/valsartan on congestion. Methods: We analyzed participants from PARADIGM-HF (Prospective Comparison of Angiotensin Receptor-Neprilysin Inhibitor With Angiotensin Converting Enzyme Inhibitor to Determine Impact on Global Mortality and Morbidity in HF) with an available physical examination at baseline. We examined the association of the number of signs of congestion (jugular venous distention, edema, rales, and third heart sound) with the primary outcome (cardiovascular death or HF hospitalization), its individual components, and all-cause mortality using time-updated, multivariable-adjusted Cox regression. We further evaluated whether sacubitril/valsartan reduced congestion during follow-up and whether improvement in congestion is related to changes in clinical outcomes and quality of life, assessed by Kansas City Cardiomyopathy Questionnaire overall summary scores. Results: Among 8380 participants, 0, 1, 2, and 3+ signs of congestion were present in 70%, 21%, 7%, and 2% of patients, respectively. Patients with baseline congestion were older, more often female, had higher MAGGIC risk scores (Meta-Analysis Global Group in Chronic Heart Failure) and lower Kansas City Cardiomyopathy Questionnaire overall summary scores ( P <0.05). After adjusting for baseline natriuretic peptides, time-updated Meta-Analysis Global Group in Chronic Heart Failure score, and time-updated New York Heart Association class, increasing time-updated congestion was associated with all outcomes ( P <0.001). Sacubitril/valsartan reduced the risk of the primary outcome irrespective of clinical signs of congestion at baseline ( P =0.16 for interaction), and treatment with the drug improved congestion to a greater extent than did enalapril ( P =0.011). Each 1-sign reduction was independently associated with a 5.1 (95% CI, 4.7–5.5) point improvement in Kansas City Cardiomyopathy Questionnaire overall summary scores. Change in congestion strongly predicted outcomes even after adjusting for baseline congestion ( P <0.001). Conclusions: In HF with reduced ejection fraction, the physical exam continues to provide significant independent prognostic value even beyond symptoms, natriuretic peptides, and Meta-Analysis Global Group in Chronic Heart Failure risk score. Sacubitril/valsartan improved congestion to a greater extent than did enalapril. Reducing congestion in the outpatient setting is independently associated with improved quality of life and reduced cardiovascular events, including mortality. Clinical Trial Registration: https://www.clinicaltrials.gov . Unique identifier: NCT01035255.

Abstract Technology-rich learning environments (TREs) play an increasingly important role for 21st century education, and the emotions learners experience in these environments are pivotal for their cognitive and affective learning gains. The contributors to this special issue address the importance of understanding and measuring emotions in TREs as a mechanism for fostering learning. In particular, the special issue situates this research with a systemic review and meta-analysis of the literature on emotions in TREs. Following this review empirical research is presented on measuring emotions in the context of learning with TREs in multiple domains, including medicine, history, and mathematics. These researchers use concurrent measures to capture students’ cognitive, metacognitive and affective processes before, during, and after solving problems, documenting the complex role of such processes as individuals and groups learn with technology. The special issue concludes with two commentaries that point the way to next steps in this field of research.

IntroductionSpecialised early intervention services have demonstrated improved outcomes in first-episode psychosis (FEP); however, clinical gains may not be sustained after patients are transferred to regular care. Moreover, many patients with FEP remain socially isolated with poor functional outcomes. To address this, our multidisciplinary team has developed a moderated online social media therapy (HORYZONS) designed to enhance social functioning and maintain clinical gains from specialist FEP services. HORYZONS merges: (1) peer-to-peer social networking; (2) tailored therapeutic interventions; (3) expert and peer-moderation; and (4) new models of psychological therapy (strengths and mindfulness-based interventions) targeting social functioning. The aim of this trial is to determine whether following 2 years of specialised support and 18-month online social media-based intervention (HORYZONS) is superior to 18 months of regular care.Methods and analysisThis study is a single-blind randomised controlled trial. The treatment conditions include HORYZONS plus treatment as usual (TAU) or TAU alone. We recruited 170 young people with FEP, aged 16–27 years, in clinical remission and nearing discharge from Early Psychosis Prevention and Intervention Centre, Melbourne. The study includes four assessment time points, namely, baseline, 6-month, 12-month and 18-month follow-up. The study is due for completion in July 2018 and included a 40-month recruitment period and an 18-month treatment phase. The primary outcome is social functioning at 18 months. Secondary outcome measures include rate of hospital admissions, cost-effectiveness, vocational status, depression, social support, loneliness, self-esteem, self-efficacy, anxiety, psychological well-being, satisfaction with life, quality of life, positive and negative psychotic symptoms and substance use. Social functioning will be also assessed in real time through our Smartphone Ecological Momentary Assessment tool.Ethics and disseminationMelbourne Health Human Research Ethics Committee (2013.146) provided ethics approval for this study. Findings will be made available through scientific journals and forums and to the public via social media and the Orygen website.Trial registration numberACTRN12614000009617; Pre-results.

Continuing professional development (CPD) is important to ensure teachers continuously maintain and update the best practice knowledge and skills needed for the profession. Limited research into CPD in physical education (PE-CPD) suggests that current provisions are largely ineffective, particularly regarding access, and the specific teaching of motor skills (e.g. throw, catch, run). Improved PE-CPD is clearly needed, and online programmes may provide a promising avenue for more accessible and effective delivery. Digital models of PE-CPD are in the early stages of use, and as yet we know very little about PE teachers’ experiences of online CPD. Thus, the present study aimed to (i) explore elementary school PE teachers’ perceptions of online PE-CPD; and (ii) provide recommendations on the development and provision of future online PE-CPD, with a particular focus on motor skill instruction and assessment. Twenty-two PE teachers participated in focus group discussions, which were analysed in NVivo 11 using an inductive thematic approach. Three major themes and several subthemes were developed from the data. First, there was significant teacher motivation and perceived need for online PE-CPD, mainly in relation to accessibility. Second, and despite this perceived need, teachers reported considerable caution around its use, especially regarding a perceived lack of a ‘community of practice’. Third, teachers provided multiple suggestions for future online PE-CPD design and delivery, including that it: (i) be evidence-based; (ii) provide pedagogical content knowledge and not just content knowledge; (iii) be informed by teachers and translatable to practice; (iv) facilitate communities of practice; (v) be interactive; (vi) be simple to navigate; and (vii) be highly visual. It is clear from teacher feedback that while online PE-CPD provides new opportunities, there are still significant limitations. This research provides novel insights and valuable recommendations that could optimise the success of future online PE-CPD offerings.

Abstract Understanding emotions in technology-based learning environments (TBLEs) has become a paramount goal across different research communities, but to date, these have operated in relative isolation. Based on control-value theory (Pekrun, 2006), we reviewed 186 studies examining emotions in TBLEs that were published between 1965 and 2018. We extracted effect sizes quantifying relations between emotions (enjoyment, curiosity/interest, anxiety, anger/frustration, confusion, boredom) and their antecedents (control-value appraisals, prior knowledge, gender, TBLE characteristics) and outcomes (engagement, learning strategies, achievement). Mean effects largely supported hypotheses (e.g., positive relations between enjoyment and appraisals, achievement, and cognitive support) and remained relatively stable across moderators. These findings imply that levels of emotions differ across TBLEs, but that their functional relations with appraisals and learning are equivalent across environments. Implications for research and designing emotionally sound TBLEs are discussed.

Background and Purpose— Implementation of nurse-initiated protocols to manage fever, hyperglycemia, and swallowing dysfunction decreased death and disability 90 days poststroke in the QASC trial (Quality in Acute Stroke Care) conducted in 19 Australian acute stroke units (2005–2010). We now examine long-term all-cause mortality. Methods— Mortality was ascertained using Australia’s National Death Index. Cox proportional hazards regression compared time to death adjusting for correlation within stroke units using the cluster sandwich (Huber–White estimator) method. Primary analyses included treatment group only unadjusted for covariates. Secondary analysis adjusted for age, sex, marital status, education, and stroke severity using multiple imputation for missing covariates. Results— One thousand and seventy-six participants (intervention n=600; control n=476) were followed for a median of 4.1 years (minimum 0.3 to maximum 70 months), of whom 264 (24.5%) had died. Baseline demographic and clinical characteristics were generally well balanced by group. The QASC intervention group had improved long-term survival (>20%), but this was only statistically significant in adjusted analyses (unadjusted hazard ratio [HR], 0.79; 95% confidence interval [CI], 0.58–1.07; P =0.13; adjusted HR, 0.77; 95% CI, 0.59–0.99; P =0.045). Older age (75–84 years; HR, 4.9; 95% CI, 2.8–8.7; P <0.001) and increasing stroke severity (HR, 1.5; 95% CI, 1.3–1.9; P <0.001) were associated with increased mortality, while being married (HR, 0.70; 95% CI, 0.49–0.99; P =0.042) was associated with increased likelihood of survival. Cardiovascular disease (including stroke) was listed either as the primary or secondary cause of death in 80% (211/264) of all deaths. Conclusions— Our results demonstrate the potential long-term and sustained benefit of nurse-initiated multidisciplinary protocols for management of fever, hyperglycemia, and swallowing dysfunction. These protocols should be a routine part of acute stroke care. Clinical Trial Registration— URL: http://www.anzctr.org.au . Unique identifier: ACTRN12608000563369.

The economic burden of inactivity is substantial, with conservative estimates suggesting the global cost to health care systems is more than US$50 billion. School-based programs, including physical education and school sport, have been recommended as important components of a multi-sector, multi-system approach to address physical inactivity. Additionally, community sporting clubs and after-school programs (ASPs) offer further opportunities for young people to be physically active outside of school. Despite demonstrating promise, current evidence suggests school-based physical activity programs, community sporting clubs and ASPs are not achieving their full potential. For example, physical activity levels in physical education (PE) and ASP sessions are typically much lower than recommended. For these sessions to have the strongest effects on young people's physical activity levels and their on-going physical literacy, they need to improve in quality and should be highly active and engaging. This paper presents the Supportive, Active, Autonomous, Fair, Enjoyable (SAAFE) principles, which represent an evidence-based framework designed to guide the planning, delivery and evaluation of organized physical activity sessions in school, community sport and ASPs. In this paper we provide a narrative and integrative review of the conceptual and empirical bases that underpin this framework and highlight implications for knowledge translation and application.