The immunology and genetics of resistance of sheep to Teladorsagia circumcincta

Teladorsagia circumcincta is one of the most economically important gastrointestinal nematode parasites of sheep in cool temperate regions, to which sheep show genetically-varying resistance to infection. This is a very common parasite and viable sheep production requires the extensive use of anthelmintic drugs. However, the emergence of drug-resistant parasites has stimulated the search for alternative control strategies to curb production losses. Lambs become infected soon after weaning and begin to control parasite burden within 8-10 weeks of continual infection. This control is an acquired characteristic mediated by the development of parasite-specific antibodies. This paper describes the immunology associated with resistance and susceptibility, focussing on differential T cell activation that regulates the production of specific effector mechanisms. It continues by summarizing the methods used to identify genes that could be exploited as molecular markers of selection for resistance. In particular it focusses on the link between understanding the molecular immunology of infection and the identification of candidate genes for selection

Physical activity and depression in adolescents: cross-sectional findings from the ALSPAC cohort

Purpose: Few studies have examined the association between physical activity (PA), measured objectively, and adolescent depressive symptoms. The aim of this study was to determine whether there is an association between objective measures of PA (total PA and time spent in moderate and vigorous PA (MVPA)) and adolescent depressive symptoms. Methods: Data on 2,951 adolescents participating in ALSPAC were used. Depressive symptoms were measured using the self-report Mood and Feelings Questionnaire (MFQ) (short version). Measures of PA were based on accelerometry. The association between PA and MFQ scores was modelled using ordinal regression. Results: Adolescents who were more physically active (total PA or minutes of MVPA) had a reduced odds of depressive symptoms [ORadj total PA (tertiles): medium 0.82 (95% CI: 0.69, 0.97); high 0.69 (95% CI: 0.57, 0.83)]; ORadj per 15 min MVPA: 0.92 (95% CI: 0.86, 0.98). In a multivariable model including both total PA and the percentage of time spent in MVPA, total PA was associated with depressive symptoms (ORadj total PA (tertiles): medium 0.82 (95% CI: 0.70, 0.98); high 0.70 (95% CI: 0.58, 0.85) but the percentage of time spent in MVPA was not independently associated with depressive symptoms [ORadj MVPA (tertiles) medium 1.05 (95% CI: 0.88, 1.24), high 0.91 (95% CI: 0.77, 1.09)]. Conclusions: The total amount of PA undertaken was associated with adolescent depressive symptoms, but the amount of time spent in MVPA, once total PA was accounted for, was not. If confirmed in longitudinal studies and randomised controlled trials, this would have important implications for public health messages.Nicola J. Wiles, Anne M. Haase, Debbie A. Lawlor, Andy Ness, Glyn Lewi

Urinary biomarkers of physical activity: candidates and clinical utility

Chronic physical inactivity is a major risk factor for a number of important lifestyle diseases, while inappropriate exposure to high physical demands is a risk factor for musculoskeletal injury and fatigue. Proteomic and metabolomic investigations of the physical activity continuum - extreme sedentariness to extremes in physical performance - offer increasing insight into the biological impacts of physical activity. Moreover, biomarkers, revealed in such studies, may have utility in the monitoring of metabolic and musculoskeletal health or recovery following injury. As a diagnostic matrix, urine is non-invasive to collect and it contains many biomolecules, which reflect both positive and negative adaptations to physical activity exposure. This review examines the utility and landscape of biomarkers of physical activity with particular reference to those found in urine

Increasing physical activity in stroke survivors using STARFISH, an interactive mobile phone application: a pilot study

Background: Following stroke, people are generally less active and more sedentary which can worsen outcomes. Mobile phone applications (apps) can support change in health behaviours. We developed STARFISH, a mobile phone app-based intervention, which incorporates evidence-based behaviour change techniques (feedback, self-monitoring and social support), in which users’ physical activity is visualised by fish swimming. Objective: To evaluate the potential effectiveness of STARFISH in stroke survivors. Method: Twenty three people with stroke (12 women; age: 56.0 ± 10.0 years, time since stroke: 4.2 ± 4.0 years) from support groups in Glasgow completed the study. Participants were sequentially allocated in a 2:1 ratio to intervention (n=15) or control (n=8) groups. The intervention group followed the STARFISH programme for six weeks; the control group received usual care. Outcome measures included physical activity, sedentary time, heart rate, blood pressure, body mass index, Fatigue Severity Scale, Instrumental Activity of Daily Living Scale, Ten Metre Walk Test, Stroke Specific Quality of Life Scale, Psychological General Well-Being Index. Results: The average daily step count increased by 39.3% (4158 to 5791 steps/day) in the intervention group and reduced by 20.2% (3694 to 2947 steps/day) in the control group (p=0.005 for group-time interaction). Similar patterns of data and group-time interaction were seen for walking time (p=0.002) and fatigue (p= 0.003). There were no significant group-time interactions for other outcome measures. Conclusion: Use of STARFISH has the potential to improve physical activity and health outcomes in people after stroke and longer term intervention trials are warranted