Heavy cannabis use and depressive symptoms in three Aboriginal communities in Arnhem Land, Northern Territory

OBJECTIVE: To determine the extent to which depressive symptoms are associated with heavy cannabis use in an Aboriginal population in Arnhem Land, Northern Territory. DESIGN, PARTICIPANTS AND SETTING: Cross-sectional study involving interviews with 106 Indigenous participants (57 males, 49 females) aged 13-42 years in three remote Aboriginal communities in Arnhem Land, NT, Australia. MAIN OUTCOME MEASURES: Measures of depressive symptoms (a raw score of > or = 6 out of a possible 18 on a modified version of the Patient Health Questionnaire-9) and self-reported heavy cannabis use (six or more cones daily). RESULTS: After adjusting for other substance use (tobacco, alcohol and lifetime petrol sniffing), age and sex, heavy cannabis users were four times more likely than the remainder of the sample to report moderate to severe depressive symptoms (odds ratio, 4.1; 95% CI, 1.3-13.4). CONCLUSIONS: Given its high prevalence in Indigenous populations, the development of clinical and prevention strategies for cannabis misuse are warranted.     

Effects of high intensity interval training on exercise capacity in people with cystic fibrosis: study protocol for a randomised controlled trial

Background

In people with cystic fibrosis (CF), higher exercise capacity is associated with better health-related quality of life (HRQoL), reduced risk of hospitalisation for a respiratory infection and survival. Therefore, optimisation of exercise capacity is an important treatment goal. The Australian and New Zealand clinical practice guidelines recommend that people with CF complete 30 to 60 min of moderate intensity aerobic exercise on most days of the week. This recommendation can be difficult to achieve by people with CF because of time constraints, and intolerable breathlessness and muscle fatigue during continuous exercise. In contrast, a low-volume, high intensity interval training (HIIT) program may be a more achievable and efficient training method to improve exercise capacity in people with CF.

Methods

A randomised controlled trial will be undertaken. Forty people with CF (aged ≥15 years) will be randomly allocated, on a 1:1 ratio, to either the experimental or control group. Regardless of their group allocation, all participants will be asked to continue with their usual daily treatment for the study duration. Those in the experimental group will complete 8 weeks of thrice weekly HIIT on a cycle ergometer. Those in the control group will receive weekly contact with the investigators. The primary outcome of this study is exercise capacity. Secondary outcomes are HRQoL, exercise self-efficacy, feelings of anxiety, depression and enjoyment. These outcomes will be recorded at baseline (i.e. prior to randomisation) and following the 8-week intervention period. The study will also report other outcomes of the HIIT program (cardiovascular responses, symptom response, post-exercise muscle soreness and tolerance) and behaviour change techniques such as reinforcement, feedback and goal setting, used during the HIIT program.

Discussion

This study will determine the effects of 8-weeks of supervised, low-volume HIIT, completed on a cycle ergometer on measures of exercise capacity, HRQoL, exercise self-efficacy, feelings of anxiety, depression and enjoyment. If effective, this type of training could be an attractive alternative to traditional continuous training because it may be more achievable and time efficient.

Trial registration

Australian and New Zealand Clinical Trials Registry (ANZCTR):12617001271392 (04/09/2017).

     

Antigen expression determines adenoviral vaccine potency independent of IFN and STING signaling

Recombinant adenoviral vectors (rAds) are lead vaccine candidates for protection against a variety of pathogens, including Ebola, HIV, tuberculosis, and malaria, due to their ability to potently induce T cell immunity in humans. However, the ability to induce protective cellular immunity varies among rAds. Here, we assessed the mechanisms that control the potency of CD8 T cell responses in murine models following vaccination with human-, chimpanzee-, and simian-derived rAds encoding SIV-Gag antigen (Ag). After rAd vaccination, we quantified Ag expression and performed expression profiling of innate immune response genes in the draining lymph node. Human-derived rAd5 and chimpanzee-derived chAd3 were the most potent rAds and induced high and persistent Ag expression with low innate gene activation, while less potent rAds induced less Ag expression and robustly induced innate immunity genes that were primarily associated with IFN signaling. Abrogation of type I IFN or stimulator of IFN genes (STING) signaling increased Ag expression and accelerated CD8 T cell response kinetics but did not alter memory responses or protection. These findings reveal that the magnitude of rAd-induced memory CD8 T cell immune responses correlates with Ag expression but is independent of IFN and STING and provide criteria for optimizing protective CD8 T cell immunity with rAd vaccines.     

What the Long Term Cohort Studies that Began in Childhood Have Taught Us about the Origins of Coronary Heart Disease

A limited number of observational studies were commenced in the 1970s and 1980s that have aimed to examine the child and adolescent origin of cardiovascular disease. These studies have provided, and continue to provide, critical evidence that have enhanced our understanding of the disease process, the early-life factors involved, and have informed public health and clinical guideline statements. Using data on preclinical markers of vascular health in adulthood, these studies have recently described the important role for youth lifestyle for later vascular health, provided information on the critical age in youth when risk factor associations with adult vascular health emerge, and have reported on the potential vascular benefits of resolving youth at-risk status in the transition from youth to adulthood. It is these works that we cover in detail in this review. Despite all the achievements from these studies, it is tantalizing that their most important contributions are still to come. That is, once sufficient clinical end points accrue so that analyses linking early life health to hard outcomes can be performed. These studies are a commodity and an invaluable resource that, with minimal re-investment, will provide increasing returns on cardiovascular health into the future.     

Does exercise training change physical activity in people with COPD? A systematic review and meta-analysis

A systematic review and meta-analysis was conducted to examine the effect of exercise training on daily physical activity (PA) in people with chronic obstructive pulmonary disease (COPD). MEDLINE, PubMed, EMBASE, CINAHL, Physiotherapy Evidence Database (PEDro) and Cochrane Central Register of Controlled Trials were searched from their inception to week 27 of 2010, using the keywords 'COPD,' 'exercise,' 'therapy' and 'physical activity.' All studies except case reports were eligible for inclusion provided they investigated the effects of ≥4 weeks of supervised exercise training on PA in patients with COPD. Study quality for the randomised trials (RTs) and single-group interventional studies was rated using the PEDro scale and Downs and Black Tool, respectively. No randomised controlled trials met our study criteria. The two RTs had a mean PEDro score of 5. The 5 single-group studies had a mean Downs and Black score of 19 ± 3. When combined, a small effect on PA outcomes was demonstrated (overall mean effect = 0.12; p = 0.01). Taken together, the RTs and single-group studies demonstrate that exercise training may confer a significant but small increase in PA.