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Air pollution is among the leading environmental threats to health around the world today, particularly in the context of sports and exercise. With the effects of air pollution, pollution episodes (eg, wildfire conflagrations) and climate change becoming increasingly apparent to the general population, so have their impacts on sport and exercise. As such, there has been growing interest in the sporting community (ie, athletes, coaches, and sports science and medicine team members) in practical personal-level actions to reduce the exposure to and risk of air pollution. Limited evidence suggests the following strategies may be employed: minimising all exposures by time and distance, monitoring air pollution conditions for locations of interest, limiting outdoor exercise, using acclimation protocols, wearing N95 face masks and using antioxidant supplementation. The overarching purpose of this position statement by the Canadian Academy of Sport and Exercise Medicine and the Canadian Society for Exercise Physiology is to detail the current state of evidence and provide recommendations on implementing these personal strategies in preventing and mitigating the adverse health and performance effects of air pollution exposure during exercise while recognising the limited evidence base.

Hybridization following secondary contact of genetically divergent populations can influence the range expansion of invasive species, though specific outcomes depend on the environmental dependence of hybrid fitness. Here, using two genetically and ecologically divergent threespine stickleback lineages that differ in their history of freshwater colonization, we estimate fitness variation of parental lineages and hybrids in semi-natural freshwater ponds with contrasting histories of nutrient loading. In our experiment, we found that fish from the older freshwater lineage (Lake Geneva) and hybrids outperformed fish from the younger freshwater lineage (Lake Constance) in terms of both growth and survival, regardless of the environmental context of our ponds. Across all ponds, hybrids exhibited the highest survival. Although wild-caught adult populations differed in their functional and defence morphology, it is unclear which of these traits underlie the fitness differences observed among juveniles in our experiment. Overall, our work suggests that when hybrid fitness is insensitive to environmental conditions, as observed here, introgression may promote population expansion into unoccupied habitats and accelerate invasion success.

Monoclonal antibodies (mAbs) are used extensively as biotherapeutics for chronic and acute conditions. Production of mAbs is lengthy and expensive, with protein A affinity capture the most costly step, due both to the nature of the resin and its marked reduction in binding capacity with repeated use. Our previous studies using in situ ATR-FTIR spectroscopy indicated that loss in protein A binding capacity is not the result of leaching or degradation of protein A ligand, suggesting fouling is the principal cause. Here we explore binding behavior and resin capacity loss using Raman spectroscopy. Our data reveal a distinct Raman spectral fingerprint for mAb bound to the protein A ligand of MabSelect SuRe. The results show that the drop in static binding capacity (SBC) previously observed for used protein A resin is discernible by Raman spectroscopy in combination with partial least-squares regression. The SBC is lowest (35.76 mg mL-1) for used inlet resin compared to used outlet (40.17 mg mL-1) and unused resin samples (70.35 mg mL-1). Depth profiling by Raman spectroscopy indicates that at below saturating concentrations (∼18 mg mL-1), binding of mAb is not homogeneous through used resin beads with protein binding preferentially to the outer regions of the bead, in contrast to fully homogeneous distribution through unused control MabSelect SuRe resin beads. Analysis of the Raman spectra indicates that one foulant is irreversibly bound mAb. The presence of irreversibly bound mAb and host cell proteins was confirmed by mass spectrometric analysis of used resin beads.

OBJECTIVES To describe and delineate the epidemiological profile of concussion injuries in individuals with attention-deficit/hyperactivity disorder (ADHD) by identifying characteristics associated with poorer outcomes. SETTING One hundred forty-four multidisciplinary concussion-specialized clinics across Canada. PARTICIPANTS Two hundred twenty-two individuals with a diagnosis of ADHD aged 7 to 53 years who sustained a concussion within the last year. DESIGN Multicenter cohort study. MAIN MEASURES Candidate predictor variables (ie, age, sex, concussion history, loss of consciousness, and internalized and learning disorder comorbidities) were collected through oral interviews. Concussion outcomes (ie, symptom severity and total number of symptoms experienced) were assessed with the Sport Concussion Assessment Tool. RESULTS Older age, female sex, and the presence of an internalized disorder predicted poorer concussion outcomes in individuals with ADHD. Males with ADHD reported significantly worse concussion outcomes with increasing age, while outcomes remained fairly stable across age in females. CONCLUSION The current findings represent a promising step toward the optimization of concussion management in individuals with ADHD. With a more thorough understanding of the demographic and comorbidity variables, clinical care decisions and intervention strategies can be developed to help individuals with ADHD who might be at a higher risk of poorer outcomes following a concussion.

1) To determine which characteristics of adolescent athletes with SRC are associated with 'early' versus 'late' presentation for multimodal treatment; 2) to build a propensity score to investigate the effects of treatment timing during the management of SRCs.Associations between early (0-7 days) versus late (8-28 days) presentation for treatment and pre-specified sociodemographic, pre-injury and injury characteristics were investigated in a historical cohort study of 2949 multi-sport athletes across Canada aged 12-18 years diagnosed with a SRC in community-based healthcare clinics.Early presentation was associated with being male, completing a pre-injury baseline assessment, and responding 'yes' or 'no' to having a diagnosed learning disability. Older athletes who reported previous SRCs were less likely to present early. The propensity score demonstrated an area under the curve of 0.71 (95% CI, 0.69 to 0.73).Male athletes with a completed baseline assessment were more likely to seek early treatment following a SRC, and older athletes who reported a greater number of previous SRCs were less likely to present early. External validation of the propensity score is needed before examining the impact of treatment timing on adolescent athlete recovery outcomes.1) Trouver les caractéristiques des athlètes adolescents ayant subi une CCLS qui sont associées à la consultation précoce et à une consultation tardive; 2) établir un score de propension pour étudier les effets du moment du traitement pendant la prise en charge de la CCLS.Les liens entre la consultation précoce (de 0 à 7 jours) et la consultation tardive (de 8 à 28 jours) et les caractéristiques sociodémographiques, les caractéristiques avant la blessure et les caractéristiques après des blessure prédéterminées ont été examinés au cours d’une étude de cohorte historique menée auprès de 2 949 adolescents multisports répartis dans toutes les régions du Canada, âgés de 12 à 18 ans, chez lesquels une CCLS avait été diagnostiquée dans des cliniques de santé communautaires.La consultation précoce a été associée au sexe masculin, à une évaluation de départ avant la blessure et à la présence ou à l’absence d’un trouble de l’apprentissage. Les athlètes plus âgés ayant signalé des CCLS antérieures étaient moins susceptibles de consulter précocement. Le score de propension a démontré une aire sous la courbe de 0,71 (IC à 95 %: 0,69 à 0,73).Les athlètes masculins ayant subi une évaluation de départ étaient plus susceptibles de consulter précocement après une CCRS alors que les athlètes âgés ayant déclaré un plus grand nombre de CCRS antérieures étaient moins susceptibles de consulter précocement. Une validation externe du score de propension serait nécessaire avant d’examiner l’effet du moment de la consultation sur les résultats de récupération chez les athlètes adolescents.

ObjectiveConduct a meta-analysis to determine the impact of traumatic spinal cord injury (SCI) on echocardiographic measurements of left ventricular (LV) structure and function.MethodsMEDLINE and Embase were used for primary searches of studies reporting LV echocardiographic data in individuals with SCI. Of 378 unique citations, 36 relevant full-text articles were retrieved, and data from 27 studies were extracted for meta-analyses. Literature searches, article screening and data extraction were completed by two independent reviewers and compared for agreement. Primary analyses compared echocardiographic indices between individuals with SCI and able-bodied individuals, using a random effects model.ResultsData are reported as pooled effect estimates (95% CI). Data from 22 articles (474 participants) were included in the primary meta-analysis. Compared with able-bodied individuals, individuals with SCI had reductions to LV stroke volume of 11.8 mL (95% CI −17.8 to −5.9, pindex of −7.7 g/m2 (95% CI −11.6 to −3.8, pConclusionsIndividuals with SCI have smaller LV volumes and mass, and altered systolic and diastolic function. While this meta-analysis demonstrates important alterations to echocardiographic measures of cardiac structure and function at rest, future work should consider the impacts of SCI on the heart’s capacity or ‘reserve’ to respond to physiological challenges.PROSPERO registration numberCRD42017072333.

Urine nitrogen excretion (g/d; UN) represent a significant environmental impact for both confinement feeding and pastoral based dairy systems. It is difficult to measure UN directly due to animal handling and labor requirements, especially in forage based production systems. The currently available milk urea nitrogen (MUN) equations have been shown to overestimate UN excretion of grazing dairy cows compared with an equation using urinary creatinine and UN concentration, indicating that diet may alter the relationship between MUN and UN. This potential was explored using data retrieved (treatment means: n = 69 and 27 for fresh forage [FF] and total mixed ration [TMR] fed cattle, respectively) from the literature and new data obtained from dairy cows fed FF (n = 15) in metabolism crates was used to test the new equations. The TMR data from literature was further split into a training set (to develop the model; n = 53) and a test set (to validate the model; n = 16). There was an interaction for diet type (P < 0.01) where UN (g/d) = 0.023 × MUN (mg/dL) × live-weight (kg, LW) for TMR fed cattle, (similar to a pre-established equation); however, UN (g/d) = 0.015 × MUN × LW for FF fed cattle. For FF based equations, the New MUN equation and the creatinine equation showed good precision and accuracy (Lin’s CCC = 0.79 and 0.74, respectively) and adequate predictive ability (RMSEP = 29.8 and 35.9, respectively). The new MUN equation for TMR fed cattle showed excellent accuracy and precision (Lin’s CCC = 0.87) with good predictive ability (RMSEP = 24.3) for UN excretion (observed mean = 216.5 g/d). The new equations generated during this meta-analysis provide promising predictive ability of UN excretion, which can be used for management considerations, future research, and policy making.

Adductor strains are the most commonly reported muscle injuries in adolescent soccer players and the second most common muscle injuries in adult players. Health practitioners should be aware of possible differential diagnoses, such as a pubic stress fracture or pubic apophysitis when athletes present with chronic groin pain.To present a rare case of a unilateral pelvic stress fracture of a 16-year old elite soccer player with a history of Crohn's disease.Retrospective case report (n=1).Case notes of two sports-based practitioners were reviewed and compiled retrospectively.Following activity restriction, a period of rest, conservative care, and progressive rehabilitation, this athlete was able to achieve a pain-free state with near equal iso-kinetic strength bilaterally as measured by Cybex 6000 (Cybex International Inc., Medway, MA, USA) muscle testing. Full activity was resumed 10 months after initial presentation and the athlete was able to return to playing professional soccer.This case report presents a rare diagnosis of a unilateral pubic stress fracture presenting as a strain of adductor longus. Although quite rare, differential diagnoses such as a potential underlying stress fracture should be considered when presented with chronic or recurrent groin pain.Les entorses des adducteurs sont les blessures musculaires les plus fréquemment signalées chez les joueurs de soccer adolescents et les deuxièmes blessures musculaires les plus fréquentes chez les joueurs adultes. Les professionnels de la santé devraient connaitre les diagnostics différentiels possibles, comme une fracture de stress du pubis ou une apophysite pubienne lorsque les athlètes présentent des douleurs chroniques à l’aine.Présenter un cas rare de fracture de stress pelvien unilatéral chez un joueur de soccer d’élite de 16 ans ayant des antécédents de maladie de Crohn.Cas clinique rétrospectif (n=1).Les notes de cas de deux praticiens du sport ontAprès une période de restriction d’activité, une période de repos, des soins conservateurs et une rééducation progressive, cet athlète a pu atteindre unCe cas clinique présente un diagnostic rare de fracture de stress pubien unilatéral se présentant sous la forme d’une lésion du moyen adducteur. Bien qu’ils soient assez rares, les diagnostics différentiels tels qu’une fracture de stress sousjacente potentielle devraient

Cervical spinal cord injury (C-SCI) is a devastating condition that leads to significant impairments in both the cardiovascular and respiratory response to aerobic exercise. As the heart and lungs share space within the thoracic cavity it follows that changes in one system will affect the other. Therefore, the purpose of this thesis was to examine heart-lung interactions in C-SCI and to utilize this knowledge to enhance exercise capacity in athletes with C-SCI. The aims of this thesis were to (1) compare the cardiorespiratory response to maximal and sub-maximal exercise following C-SCI to able-bodied individuals, with a particular focus on operating lung volumes (Study #1, Chapter 3); (2) to examine the effects of respiratory loading on lung volumes and left-ventricular function during head-up tilt (Study #2, Chapter 4); and (3) to assess the effects of a combined inspiratory and expiratory respiratory muscle training (i.e. RMT) intervention in elite athletes with C-SCI (Study #3, Chapter 5). Laboratory-based incremental arm ergometry testing demonstrated that C-SCI is associated with a limited exercise capacity compared to able-bodied individuals along with an altered respiratory pattern that is characterized by dynamic hyperinflation and reduced tidal volume. By manipulating inspiratory and expiratory esophageal pressure in individuals with C-SCI, it was demonstrated that expiratory loading elicited dynamic hyperinflation that was associated with impaired left-ventricular filling, likely due to direct ventricular interaction and/or mediastinal constraint. Finally, a six-week RMT intervention in elite athletes with C-SCI was found to significantly enhance respiratory muscle strength and measures of pulmonary function and prevent dynamic hyperinflation during exercise. These changes in pulmonary function were accompanied by enhanced exercise capacity during an incremental arm ergometry test and were partly ameliorated following six-weeks of wash-out (i.e., no RMT). This thesis demonstrates that dynamic hyperinflation in individuals with C-SCI, which likely occurs due to expiratory muscle weakness, limits left ventricular filling and is associated with an attenuated exercise capacity compared to able-bodied individuals. RMT improved respiratory muscle strength and prevented dynamic hyperinflation in individuals with C-SCI and enhanced exercise capacity.

The primary objective of this study was to identify the self-reported lifetime prevalence of diagnosed concussions among Canadian ice hockey players aged 10 to 25 years old.Medical records were identified for n=5223 athletes whom completed comprehensive baseline assessments with a Canada-wide network of private concussion management clinics. Variables extracted included: sex, age, diagnosed history of and number of prior concussions, diagnosed health condition(s), and Post-Concussion Symptom Scale scores.Approximately 22% of all athletes, 21.7% of females and 21.8% of males reported that they had sustained at least one diagnosed concussion. Age was significantly associated with history of concussion as was having an additional health condition. Sex was not significantly associated with a history of concussion.Lifetime history of concussion prevalence estimates aligned closely with estimates previously published. Future investigations should seek to establish the prevalence of concussions that occur during ice hockey games and practices alone.L’objectif principal de cette étude était de déterminer la prévalence autodéclarée au cours de la vie des commotions cérébrales diagnostiquées chez les joueurs canadiens de hockey sur glace âgés de 10 à 25 ans.Des dossiers médicaux ont été identifiés pour 5223 athlètes qui ont effectué des évaluations de base complètes avec un réseau pancanadien de cliniques privées de gestion des commotions cérébrales. Les variables extraites comprenaient : le sexe, l’âge, les antécédents diagnostiqués et le nombre de commotions cérébrales antérieures, le ou les problèmes de santé diagnostiqués et les scores de l’échelle des symptômes après la commotion cérébrale.Environ 22 % de tous les athlètes, 21,7 % des femmes et 21,8 % des hommes ont déclaré avoir reçu au moins un diagnostic de commotion cérébrale. L’âge était associé de façon significative aux antécédents de commotion cérébrale tout comme le fait d’avoir un autre problème de santé. Le sexe n’était pas associé de façon significative à des antécédents de commotion cérébrale.Les estimations de la prévalence des antécédents de commotion cérébrale au cours de la vie concordent étroitement avec les estimations publiées antérieurement. Les enquêtes futures devraient chercher à établir la prévalence des commotions cérébrales qui surviennent uniquement pendant les parties et les pratiques de hockey sur glace.

Concussions are among the most common neurological conditions, with emergency departments and sports injury clinics seeing hundreds of patients each year. The consideration of risk factors such as age, sex, and comorbid conditions are very important when looking at individual physiological and psychological outcomes after a concussion. The purpose of this study was to look at four comorbid conditions (depression, anxiety, behavioural disorder, or learning disability) and identify any interactions with age and sex in symptom presentation after suffering a concussion. A total of 4,865 participants from the CCMI (Complete Concussion Management Inc.) dataset were used with 1,577 self-identified with a diagnosis of anxiety, depression, a behavioural disorder, or a learning disability. Fixed-factor analyses of variance were used with age and sex as fixed, grouping factors and symptom total and severity as dependent measures. For the individuals who did not have one of the 4 mental health conditions (3,288 control participants), symptom total and symptom severity increased with age (p<0.05), and females showed more symptoms and a higher symptom severity than males across all ages (p<0.05). A diagnosis of anxiety or depression exacerbated total symptoms and symptom severity from 25–50% above control levels in the 19 and under age groups, while depression or anxiety exacerbated total symptoms and severity by 10–15% in males more than females over 20. A diagnosis of a behavioural disorder or a learning disability exacerbated symptom severity by approximately 50% above control levels in 13–19–year-old females and in males of 30 years and older. This study highlights how the presence of a mental health condition may alter concussion symptom presentation dependent on age and sex. The identification of risk factors and how they may interact can be of great value to health care providers who manage concussion symptoms and recovery.

The absence of tumor necrosis factor (TNF) causes lethal infection by Leishmania major in normally resistant C57BL/6J (B6.WT) mice. The underlying pathogenic mechanism of this fatal disease has so far remained elusive. We found that B6.WT mice deficient for the tnf gene (B6.TNF−/−) displayed not only a non-healing cutaneous lesion but also a serious infection of the liver upon L. major inoculation. Infected B6.TNF−/− mice developed an enlarged liver that showed increased inflammation. Furthermore, we detected an accumulating monocyte-derived macrophage population (CD45+F4/80+CD11bhiLy6Clow) that displayed a M2 macrophage phenotype with high expression of CD206, arginase-1, and IL-6, supporting the notion that IL-6 could be involved in M2 differentiation. In in vitro experiments, we demonstrated that IL-6 upregulated M-CSF receptor expression and skewed monocyte differentiation from dendritic cells to macrophages. This was countered by the addition of TNF. Furthermore, TNF interfered with the activation of IL-6-induced gp130-signal transducer and activator of transcription (STAT) 3 and IL-4-STAT6 signaling, thereby abrogating IL-6-facilitated M2 macrophage polarization. Therefore, our results support the notion of a general role of TNF in the inflammatory activation of macrophages and define a new role of IL-6 signaling in macrophage polarization downstream of TNF.

Objective(s): To determine the profile of patients with brain tumors who receive occupational therapy (OT) services after acute care discharge. Design: A retrospective cohort study using the Discharge Abstract Database and the Homecare Database, population based healthcare administrative databases. Setting: Ontario, Canada between fiscal years 2004/05 and 2008/09. Participants: Patients with malignant, benign, and unspecified brain tumors who received post-acute OT services identified by specified International Classification of Diseases Version 10 Codes. Interventions: N/A. Main Outcome Measure(s): Number of brain tumor cases, patient and clinical characteristics, and discharge destinations from acute care of those who received post-acute OT services. Results: During the study period, there were 3,199 patients with brain tumors who received post-acute OT services in the homecare setting; 78.2% had malignant brain tumors, 12.4% had benign brain tumors, and 9.4% had unspecified brain tumors. Of these patients, those with benign brain tumors were older (63.3 years, SDZ17.6 vs. 59 years, SDZ16.4 for malignant tumors and 60.2 years, SDZ20.9 for unspecified brain tumors), a higher percentage were female (65.2% vs. 51.4% for malignant and 47.8% for unspecified brain tumors), and 46% spent at least one day in intensive care units (vs. 28.2% for malignant and 16.6% for unspecified brain tumors. More than 90% of patients received in-home OT services. Conclusions: As survival rates increase, OT may play a greater role in recovery of clients with brain tumors. This paper helps to recognize the characteristics of patients with different types of brain tumors that can assist in the planning and delivery of OT services for this population.

Cutaneous leishmaniasis in resistant C57BL/6 (B6.WT) mice is resolved spontaneously by Th-1 mediated production of TNF-α and IFN-γ, with consequent induction of inducible nitric oxide synthase. Intriguingly, C57BL/6 mice with a TNF gene knockout (B6.TNF−/−) show uncontrolled fatal infection involving the liver and spleen, which are the two main targets in visceral leishmaniasis. The exact role of TNF or specific mechanism, which is responsible for the fatal outcome of Leishmania infection in this gene-deficient mouse strain, is not yet understood. B6.TNF−/− mice spleen significantly enlarged from Day 28 post-infection, and they were more than 2-fold larger than B6.WT mice on Day 35 and Day 42. To confirm Leishmania infection in the spleen, limiting dilution assay was recruited and showed Leishmania existed since Day 21 in B6.TNF−/− mice, but there was none evident in B6.WT mice. Diff Quik stain results confirmed that architecture of spleen in B6.TNF−/− was disorganized and white and red pulps were no longer clearly separated. Cells infected with Leishmania were dispersed throughout the spleen and lymph cells infiltrated. A gradually increasing population CD45+CD11b+CD11chighCCR2+Ly6C+F4/80high was emerged in B6.TNF−/− mice, which had both dendritic cell and macrophages like phenotype. In vitro, at steady state, macrophages from B6.TNF−/− mice showed no difference comparing to B6.WT. After exposure with Leishmania promastigotes, they showed potential M2-like phenotype and more easily succumbed to infection We are currently sorting this population from B6.TNF−/− mice and examining the characteristics and potential mechanisms that may affect the spleen immunity against Leishmania major infection in the absence of TNF.

Biomarkers have proven to be critical tools in both cardiovascular clinical practice and clinical research. In clinical practice, biomarkers are used to identify patients at risk for disease, stratify disease severity, guide intervention decisions and monitor patient response to therapy. Biomarkers are also used extensively to improve the design of cardiovascular clinical trials, identify ‘at-risk’ populations, allow for preliminary screening for response, identify appropriate dose ranges, study subgroup differences and identify early safety concerns. The purpose of this paper is to describe current key cardiovascular biomarker initiatives and to outline some of the important considerations in applying these biomarkers in a clinical trial setting, utilizing the examples of HDL cholesterol, HDL-targeted therapies and imaging tools used to assess HDL-targeted therapies as a case study.