Transformative learning for a sustainable and healthy future through ecosystem approaches to health: insights from 15 years of co-designed ecohealth teaching and learning experiences

This paper presents insights from the work of the Canadian Community of Practice in Ecosystem Approaches to Health (CoPEH-Canada) and 15 years (2008-2022) of land-based, transdisciplinary, learner-centred, transformative learning and training. We have oriented our learning approaches to Head, Hands, and Heart, which symbolise cognitive, psychomotor, and affective learning, respectively. Psychomotor and affective learning are necessary to grapple with and enact far-reaching structural changes (eg, decolonisation) needed to rekindle healthier, reciprocal relationships with nature and each other. We acknowledge that these approaches have been long understood by Indigenous colleagues and communities. We have developed a suite of teaching techniques and resources through an iterative and evolving pedagogy based on participatory approaches and operating reciprocal, research-pedagogical cycles; integrated different approaches and ways of knowing into our pedagogy; and built a networked Community of Practice for continued learning. Planetary health has become a dominant framing for health-ecosystem interactions. This Viewpoint underscores the depth of existing scholarship, collaboration, and pedagogical expertise in ecohealth teaching and learning that can inform planetary health education approaches.

Climate Change, Physical Activity and Sport: A Systematic Review

BACKGROUND

Climate change impacts are associated with dramatic consequences for human health and threaten physical activity (PA) behaviors.

OBJECTIVE

The aims of this systematic review were to present the potential bidirectional associations between climate change impacts and PA behaviors in humans and to propose a synthesis of the literature through a conceptual model of climate change and PA.

METHODS

Studies published before October 2020 were identified through database searches in PubMed, PsycARTICLES, CINAHL, SPORTDiscus, GreenFILE, GeoRef, Scopus, JSTOR and Transportation Research Information Services. Studies examining the associations between PA domains and climate change (e.g., natural disasters, air pollution, and carbon footprint) were included.

RESULTS

A narrative synthesis was performed and the 74 identified articles were classified into 6 topics: air pollution and PA, extreme weather conditions and PA, greenhouse gas emissions and PA, carbon footprint among sport participants, natural disasters and PA and the future of PA and sport practices in a changing world. Then, a conceptual model was proposed to identify the multidimensional associations between climate change and PA as well as sport practices. Results indicated a consistent negative effect of air pollution, extreme temperatures and natural disasters on PA levels. This PA reduction is more severe in adults with chronic diseases, higher body mass index and the elderly. Sport and PA communities can play an important mitigating role in post-natural disaster contexts. However, transport related to sport practices is also a source of greenhouse gas emissions.

CONCLUSION

Climate change impacts affect PA at a worldwide scale. PA is observed to play both a mitigation and an amplification role in climate changes.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42019128314.

Motivational theory-based interventions on health of people with several mental illness: A systematic review and meta-analysis

Motivational theory-based interventions are known to be effective for increasing physical activity (PA) in the general population but their effects in people with severe mental illness are poorly understood. Therefore, we conducted a meta-analysis on the effect of these interventions on PA and cardiometabolic risk factors. A systematic search of randomized controlled trials through 6 databases was carried out from inception to March 2019. Analyses were conducted using random-effect models. Weighted mean difference (WMD) were used as effect size when outcomes had the same units, otherwise Hedge's g was used. Fourteen articles including 2128 participants were identified. Motivational theory-based interventions were effective in increasing PA (g = 0.27, 95%CI[0.03; 0.51], p = .003), reducing weight (WMD = -1.87 kg, 95%CI[-2.98; -0.76], p = .001), body mass index (WMD = -0.82 kg/m², 95%CI[-1.23; -0.41], p = .009), waist circumference (WMD = -1.91 cm, 95%CI[-3.63; -0.18], p = .03) and fasting glucose (g = -0.17, 95%CI[-0.34; -0.001], p = .04). Larger effect sizes were found in interventions based on only one theoretical model of motivation. In conclusion, interventions using motivational theories are effective to improve PA levels and the cardiometabolic health profile of people with severe mental illness. Systematic review registration: CRD42018104445.

Association between daily level of objective physical activity and C-Reactive protein in a representative national sample of adults with self-reported diagnosed arthritis or fibromyalgia

PURPOSE

Examine the association between physical activity and sedentary time with high sensitivity C-Reactive protein levels in adults with arthritis and fibromyalgia. We also investigated the dose of physical activity that was associated with lower clinical levels of high sensitivity C-Reactive protein (< 3 mg/L).

MATERIALS AND METHODS

Observational design was used to evaluate the variables of interest-based on the Canadian Health Measures Survey cycle 1-3 (2007-2012). Generalized adjusted additive models were used to explore the shape of the association between high sensitivity C-Reactive protein, daily physical activity, step count and sedentary time. High sensitivity C-Reactive protein was measured with blood samples. Physical activity, number of steps and sedentary time were objectively assessed using an Actical accelerometer.

RESULTS

Daily moderate to vigorous physical activity and step count were significantly associated with lower high sensitivity C-Reactive protein levels, but daily light physical activity and sedentary time were not associated with high sensitivity C-Reactive protein levels, even after controlling for age, sex, daily smoking, body mass index, household income, level of education levels, marital status, work year and accelerometer wear time and season of accelerometer. Non-linear dose-response patterns were observed between daily moderate to vigorous physical activity as well as step count with high sensitivity C-Reactive protein levels. Lower high sensitivity C-Reactive protein levels were associated with 1-150 min of daily moderate to vigorous physical activity and with daily step count starting at 4000 in people with arthritis. Adults with fibromyalgia had lower levels of high sensitivity C-Reactive protein when engaging in 10-35 min of daily moderate to vigorous physical activity and in 5000-9000 daily steps. Optimal and specific doses of daily moderate to vigorous physical activity and steps were independently related to lower high sensitivity C-Reactive protein levels in adults with arthritis and fibromyalgia.

CONCLUSIONS

Daily moderate to vigorous physical activity and step count were associated with high sensitivity C-Reactive protein levels that were below the clinical threshold. Given the positive outcomes of physical activity on health, adults with arthritis and fibromyalgia may benefit from these specific recommendations.

Dose response association of objective physical activity with mental health in a representative national sample of adults: A cross-sectional study

Although higher physical activity (PA) levels are associated with better mental health, previous findings about the shape of the dose–response relationship between PA and mental health are inconsistent. Furthermore, this association may differ according to sedentary levels. We investigated the cross-sectional dose-response associations between objectively measured PA and mental health in a representative national sample of adults. We also examined whether sedentary time modified the PA—mental health associations. Based on 2007–2013 Canadian Health Measures Survey data, PA and sedentary time were measured using accelerometry among 8150 participants, aged 20 to 79 years. Generalized additive models with a smooth function were fitted to examine associations between minutes per day of moderate and vigorous PA (MVPA), light PA (LPA), daily steps (combined or not with sedentary time) and self-rated mental health. A significant curvilinear relationship between average daily minutes of MVPA and mental health was observed, with increasing benefits up to 50 minutes/day. For LPA, a more complex shape (monotonic and curvilinear) was found. For daily steps, inverted U-shaped curve suggested increasing benefits until a plateau between 5 000 and 16 000 steps. The MVPA-LPA combination was significantly associated with mental health but with a complex pattern (p < 0.0005^E-06). The tested PA-sedentary time combinations showed that increasing sedentary time decreased the positive PA-mental health associations. Non-linear dose-response patterns between the PA modalities and self-reported mental health were observed. Optimal doses of daily minutes of MVPA, LPA, MVPA combined with LPA and daily steps are independently associated with better mental health in adults. The results also suggest that PA-mental health associations could be hampered by daily sedentary time.

Cavitation Threshold with Respect to Dp/Dt: Evaluation in 29 Mm Bileaflet, Pyrolitic Carbon Heart Valves

A total of 15 bileaflet mechanical heart valves were studied in a pulse duplicator at the Helmholtz Institute (Aachen, Germany) under conditions approximating first, a physiological pressure curve and subsequently, a sinusoidal pressure curve. In this study Edwards-Duromedics valves of the modified specification were compared with the earlier version of the Edwards-Duromedics valve as well as with St. Jude Medical valves. Each valve was tested at a series of nine (9) conditions. At each condition, without altering the valve installation or the systemic conditions, each valve was filmed by two separate video systems: the Helmholtz Institute strobe light system and a high speed video recording system. All data, as recorded by each system, was then independently analyzed by both of the two contributing groups and subsequently compared. In this manner, it was possible to objectively verify not only the consistency of the data obtained, but to also determine the relative reliability of the methods for cavitation threshold detection.

2-Benzimidazolyl-9-(chroman-4-yl)-purinone derivatives as JAK3 inhibitors

A novel class of Janus tyrosine kinase 3 (JAK3) inhibitors based on a 2-benzimidazoylpurinone core structure is described. Through substitution of the benzimidazoyl moiety and optimization of the N-9 substituent of the purinone, compound 24 was identified incorporating a chroman-based functional group. Compound 24 shows excellent kinase activity, good oral bioavailability and demonstrates efficacy in an acute mechanistic mouse model through inhibition of interleukin-2 (IL-2) induced interferon-gamma (INF-gamma) production.

Imidazolylpyrimidine based CXCR2 chemokine receptor antagonists

An imidazolylpyrimidine was identified in a CXCR2 chemokine receptor antagonist screen and was optimized for potency, in vitro metabolic stability, and oral bioavailability. It was found that subtle structural modification within the series affected the oral bioavailability. Potent and orally available CXCR2 antagonists are herein reported.

Antimicrobial activity of histones from hemocytes of the Pacific white shrimp

The role of vertebrate histone proteins or histone derived peptides as innate immune effectors has only recently been appreciated. In this study, high levels of core histone proteins H2A, H2B, H3 and H4 were found in hemocytes from the Pacific white shrimp, Litopenaeus vannamei. The proteins were identified by in-gel digestion, mass spectrometry analysis, and homology searching. The L. vannamei histone proteins were found to be highly homologous to histones of other species. Based on this homology, histone H2A was cloned and its N-terminus was found to resemble the known antimicrobial histone peptides buforin I, parasin, and hipposin. Consequently, a 38 amino acid synthetic peptide identical to the N-terminus of shrimp H2A was synthesized and assayed, along with endogenous histones H2A, H2B, and H4, for growth inhibition against Micrococcus luteus. Histone H2A, purified to homogeneity, completely inhibited growth of the Gram-positive bacterium at 4.5 microm while a mixture of histones H2B and H4 was active at 3 microm. In addition, a fraction containing a fragment of histone H1 was also found to be active. The synthetic peptide similar to buforin was active at submicromolar concentrations. These data indicate, for the first time, that shrimp hemocyte histone proteins possess antimicrobial activity and represent a defense mechanism previously unreported in an invertebrate. Histones may be a component of innate immunity more widely conserved, and of earlier origin, than previously thought.

False-positive results obtained with the Alexon ProSpecT Cryptosporidium enzyme immunoassay

Cryptosporidium is known to cause diarrhea in immunocompromised patients and is also associated with outbreaks of disease due to food-borne and waterborne parasites. Traditional procedures, involving iodine staining of wet mounts of stool sediments and trichrome staining, lack the sensitivity to detect Cryptosporidium. Special staining procedures, such as the modified acid-fast and safranin stains, are generally employed. Less labor-intensive antigen detection assays have simplified detection; however, careful attention to local epidemiology is important because false-positive tests occur. Here, we report two incidents involving 62 false-positive results obtained with the Alexon ProSpecT Cryptosporidium enzyme immunoassay, which were deemed false-positive based on negative results obtained from extensive microscopic examinations.

An interlaboratory comparison of the FDA protocol for the evaluation of cavitation potential of mechanical heart valves

Five laboratories carried out measurements of cavitation threshold for a common set of six mechanical prosthetic heart valves, two each from three different manufacturers. This study was intended to evaluate to what extent FDA's current guidance for cavitation testing would lead to consistent results in a variety of laboratory settings and to seek areas for improvement in the recommended test protocol. The inter-laboratory study protocol specified: (1) characterization of the test fluid by oxygen content and electrical conductivity, (2) location and frequency response of pressure sensors, (3) determination of ventricular and atrial pressures (P) and loading rates (dP/dt) averaged over the time period of valve closure and over the time periods of 1 ms, 5 ms, and 20 ms prior to video visualization. The protocol did not specify: (1) the fluid pumping equipment to be used to generate cavitation, (2) the pump or fluid parameters adjusted to raise or lower the loading rate, (3) the equipment, technique, or sensitivity used to visualize cavitation, and (4) a specific definition of the threshold for cavitation. Results from the five laboratories are reported. Significant differences in results were observed in dP/dt and in the pressure difference across the valves during closure at cavitation threshold. Specific differences in test systems included a wide range of ventricular compliance and single valved versus double valved test systems. Three single valve systems with compliant ventricles produced results in reasonable agreement with one another. Further similarity in test equipment should be specified to assure adequate interlaboratory reliability for cavitation testing. Areas needing better specification include the design of the valve mount, the design of the cavitation generators, and qualitative criteria for detection of threshold cavitation.

Effect of structural compliance on cavitation threshold measurement of mechanical heart valves

An in vitro study was designed to evaluate the effect of structural compliance on cavitation threshold measurements of mechanical heart valves. Using a dual channel high speed video image analysis method, the experiment was carried out in a pulse duplicator under a single, simulated physiologic condition. Each valve was mounted on a compliance adjustable fixture. One video camera served as a displacement monitor, while the other monitored cavitation bubbles at the inflow side of the valve. On-line adjustment of the mounting compliance allowed for cavitation threshold detection with respect to compliance without influencing the testing condition. Visible cavitation bubbles disappeared when the compliance was increased. Ten 29 mm mitral valves, including two each of St. Jude Medical, Carbomedics, Edwards-Duromedics (ED), Edwards Tekna (ET) and Medtronic-Hall (MH) were tested. All the bileaflet valves tested in this study showed similar cavitation thresholds at a compliance range of 0.5-0.65 mil/lb at a dp/dt of 4,000 mmHg/sec (averaged dp/dt during valve closure). Under the same dp/dt, MH monoleaflet valves showed a higher compliance range of 3.5-3.8 mil/lb to achieve the cavitation threshold. This study demonstrated that the mounting compliance of the valve must be known and well controlled in order to quantify the cavitation threshold with respect to dp/dt. In addition, the more compliant sewing ring of the ET valve may be responsible for higher cavitation thresholds with respect to dp/dt as observed in previous studies. The present in vitro study suggests that the investigation of the sewing structural compliance may be essential for the evaluation of in vivo cavitation potential.

Cavitation threshold with respect to dP/dt: evaluation in 29 mm bileaflet, pyrolitic carbon heart valves

A total of 15 bileaflet mechanical heart valves were studied in a pulse duplicator at the Helmholtz Institute (Aachen, Germany) under conditions approximating first, a physiological pressure curve and subsequently, a sinusoidal pressure curve. In this study Edwards-Duromedics valves of the modified specification were compared with the earlier version of the Edwards-Duromedics valve as well as with St. Jude Medical valves. Each valve was tested at a series of nine (9) conditions. At each condition, without altering the valve installation or the systemic conditions, each valve was filmed by two separate video systems: the Helmholtz Institute strobe light system and a high speed video recording system. All data, as recorded by each system, was then independently analyzed by both of the two contributing groups and subsequently compared. In this manner, it was possible to objectively verify not only the consistency of the data obtained, but to also determine the relative reliability of the methods for cavitation threshold detection.