Age-dependent mechanical properties of tail tendons in wild-type and mimecan gene-knockout mice - A preliminary study

Mimecan, or osteoglycin, belongs to the family of small leucine-rich proteoglycans. In connective tissues mimecan is implicated in the development and maintenance of normal collagen fibrillar organization. Since collagen fibrils are responsible for tissue reinforcement, the absence of mimecan could lead to abnormal tissue mechanical properties. Here, we carried out a preliminary investigation of possible changes in the mechanical properties of tendons in mice lacking a functional mimecan gene, as a function of age. Tail tendons were dissected from mimecan gene knockout (KO) and wild type (WT) mice at ages 1, 4 and 8 months and mechanical properties evaluated using a microtensile testing equipment. Mimecan gene knockout resulted in changes in tendon elasticity- and fracture-related properties. While tendons of WT mice exhibited enhanced mechanical properties with increasing age, this trend was notably attenuated in mimecan KO tendons, with the exception of fracture strain. When genotype and age were considered as cross factors, the diminution in the mechanical properties of mimecan KO tendons was significant for yield strength, modulus and fracture strength. This effect appeared to affect the mice at 4 month old. These preliminary results suggest that mimecan may have a role in regulating age-dependent mechanical function in mouse tail tendon.

Home-based pulmonary rehabilitation early after hospitalisation in COPD (early HomeBase): protocol for a randomised controlled trial

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is characterised by exacerbations of respiratory disease, frequently requiring hospital admission. Pulmonary rehabilitation can reduce the likelihood of future hospitalisation, but programme uptake is poor. This study aims to compare hospital readmission rates, clinical outcomes and costs between people with COPD who undertake a home-based programme of pulmonary rehabilitation commenced early (within 2 weeks) of hospital discharge with usual care.

METHODS

A multisite randomised controlled trial, powered for superiority, will be conducted in Australia. Eligible patients admitted to one of the participating sites for an exacerbation of COPD will be invited to participate. Participants will be randomised 1:1. Intervention group participants will undertake an 8-week programme of home-based pulmonary rehabilitation commencing within 2 weeks of hospital discharge. Control group participants will receive usual care and a weekly phone call for attention control. Outcomes will be measured by a blinded assessor at baseline, after the intervention (week 9-10 posthospital discharge), and at 12 months follow-up. The primary outcome is hospital readmission at 12 months follow-up.

ETHICS AND DISSEMINATION

Human Research Ethics approval for all sites provided by Alfred Health (Project 51216). Findings will be published in peer-reviewed journals, conferences and lay publications.

TRIAL REGISTRATION NUMBER

ACTRN12619001122145.

Multimorbidity rehabilitation versus disease-specific rehabilitation in people with chronic diseases: a pilot randomized controlled trial

BACKGROUND

Multimorbidity (the co-existence of two or more chronic conditions in an individual) is a growing healthcare burden internationally; however, healthcare and disease management, including rehabilitation, is often delivered in single-disease siloes. The aims of this study were to (1) evaluate the safety and feasibility of multimorbidity rehabilitation compared to a disease-specific rehabilitation program in people with multimorbidity and (2) gather preliminary data regarding clinical outcomes and resource utilization to inform the design of future trials.

METHODS

A pilot feasibility randomized controlled trial with concealed allocation, assessor blinding, and intention-to-treat analysis. Seventeen individuals with a chronic disease eligible for disease-specific rehabilitation (pulmonary, cardiac, heart failure rehabilitation) and at least one other chronic condition were recruited. The intervention group attended multimorbidity exercise rehabilitation and the control group attended disease-specific exercise rehabilitation. Participants attended twice-weekly exercise training and weekly education for 8 weeks. Feasibility measures included numbers screened, recruited, and completed. Other outcome measures were change in functional exercise capacity (6-minute walk test (6MWT)), health-related quality of life (HRQoL), activities of daily living (ADL), and resource utilization.

RESULTS

Sixty-one people were screened to recruit seventeen participants (nine intervention, eight control); one withdrew prior to rehabilitation. Participants were mostly male (63%) with a mean (SD) age of 69 (9) years and body mass index of 29 (6). The intervention group attended a mean (SD) of 12 (6) sessions, and the control group attended 11 (4) sessions. One participant (6%) withdrew after commencing; two (12%) were lost to follow-up. The intervention group 6MWT distance increased by mean (SD) of 22 (45) meters (95% confidence interval - 16 to 60) compared to 22 (57) meters (95% confidence interval - 69 to 114) (control).

CONCLUSIONS

It was feasible to recruit people with multimorbidity to a randomized controlled trial of rehabilitation. A large RCT with the power to make significant conclusions about the impact on the primary and secondary outcomes is now required.

TRIAL REGISTRATION

The trial was registered with the Australian and New Zealand Clinical Trials Registry available at http://www.anzctr.org.au ACTRN12614001186640. Registered 12/11/2014.

A rehabilitation programme for people with multimorbidity versus usual care: A pilot randomized controlled trial

BACKGROUND

Multimorbidity, the coexistence of two or more chronic conditions, is common in clinical practice. Rehabilitation for people with multimorbidity may provide access to a rehabilitation programme that can address common symptoms and risk factors for multiple chronic diseases.

OBJECTIVE

The aims of this study were to (1) evaluate the feasibility of a rehabilitation programme compared to usual medical care (UMC) in people with multimorbidity and (2) gather preliminary data regarding clinical effects and impact on functional exercise capacity, activities of daily living, health-related quality of life and resource utilization.

DESIGN

A pilot feasibility parallel randomized controlled trial was undertaken. Adults with multimorbidity were randomized to the rehabilitation programme (intervention) or UMC (control). The duration of the rehabilitation programme was 8 weeks and comprised exercise (1 h, twice weekly) and education (1 h, once weekly). The UMC group did not participate in a structured exercise programme.

RESULTS

One hundred people were screened to recruit 16 participants, with a 71% completion rate for the intervention group. The rehabilitation group achieved a mean (standard deviation) improvement in 6-minute walk distance of 44 (41) m and the UMC group of 23 (29) m.

CONCLUSIONS

This study suggests that it would be feasible to conduct a larger randomized control trial investigating a rehabilitation programme for people with multimorbidity. Low uptake of the study suggests that refinement of the inclusion criteria, recruitment sources and programme model will be needed to achieve the number of participants required.

Reliability of the hand held dynamometer in measuring muscle strength in people with interstitial lung disease

OBJECTIVE

To evaluate the inter-rater and intra-rater reliability of the hand held dynamometer in measuring muscle strength in people with interstitial lung disease (ILD).

DESIGN

Test retest reliability of hand-held dynamometry for elbow flexor and knee extensor strength between two independent raters and two testing sessions.

SETTING

Physiotherapy department within a tertiary hospital.

PARTICIPANTS

Thirty participants with ILD of varying aetiology were included. Twenty participants completed the inter-rater reliability protocol (10 idiopathic pulmonary fibrosis, mean (SD) age 73 (10) years, 11 male) and 21 participants completed the intra-rater reliability protocol (10 idiopathic pulmonary fibrosis, mean age 71 (10) years, 11 male).

MAIN OUTCOME MEASURES

Mean muscle strength (kg). Agreement between the two raters and testing sessions was analyzed using Bland-Altman plots and reliability was estimated using intraclass correlation coefficients (ICC).

RESULTS

For elbow flexor strength there was a mean difference between raters of -0.6kg (limits of agreement (LOA) -5.6 to 4.4kg) and within raters of -0.3kg (LOA -2.8 to 2.3kg). The ICCs were 0.95 and 0.98, respectively. For knee extensor strength there was a mean difference between raters of -1.5kg (LOA -6.9 to 3.9kg) and within raters of -0.7kg (LOA -3.9 to 2.4kg). The ICCs were 0.95 and 0.97, respectively.

CONCLUSIONS

Hand-held dynamometry is reliable in measuring elbow flexor and knee extensor strength in people with ILD.

The benefits of exercise training in interstitial lung disease: protocol for a multicentre randomised controlled trial

Background

Interstitial lung disease encompasses a diverse group of chronic lung conditions characterised by distressing dyspnoea, fatigue, reduced exercise tolerance and poor health-related quality of life. Exercise training is one of the few treatments to induce positive changes in exercise tolerance and symptoms, however there is marked variability in response. The aetiology and severity of interstitial lung disease may influence the response to treatment. The aims of this project are to establish the impact of exercise training across the range of disease severity and to identify whether there is an optimal time for patients with interstitial lung disease to receive exercise training.

Methods/Design

One hundred and sixteen participants with interstitial lung disease recruited from three tertiary institutions will be randomised to either an exercise training group (supervised exercise training twice weekly for eight weeks) or a usual care group (weekly telephone support). The 6-minute walk distance, peripheral muscle strength, health-related quality of life, dyspnoea, anxiety and depression will be measured by a blinded assessor at baseline, immediately following the intervention and at six months following the intervention. The primary outcome will be change in 6-minute walk distance following the intervention, with planned subgroup analyses for participants with idiopathic pulmonary fibrosis, dust-related interstitial lung disease and connective-tissue related interstitial lung disease. The effects of disease severity on outcomes will be evaluated using important markers of disease severity and survival, such as forced vital capacity, carbon monoxide transfer factor and pulmonary hypertension.

Discussion

This trial will provide certainty regarding the role of exercise training in interstitial lung disease and will identify at what time point within the disease process this treatment is most effective. The results from this study will inform and optimise the clinical management of people with interstitial lung disease.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12611000416998

New Developments in Instrumentation for X-ray and Neutron Fibre Diffraction Experiments

New instrumentation has been developed for use in X-ray and neutron fibre diffraction studies to provide automated control of sample position, orientation and ambient relative humidity. A sample mount system has been constructed for the Keele fibre diffraction camera on beamline 7.2 at the Daresbury Laboratory synchrotron radiation source. This allows the sample position and orientation to be controlled remotely, without disturbing the sample environment or the detector, and permits the implementation of efficient data-collection strategies. The system can be used to record entire datasets without incurring any loss of data in the meridional region of the diffraction pattern and has also been used to record three-dimensional datasets from fibres exhibiting `double orientation'. The design incorporates a translation feature so that the effects of radiation damage during data collection can be minimized. An automated humidity control system has also been constructed and can be used in either X-ray or neutron fibre diffraction studies where the water content of samples is a critical parameter and careful control of the relative humidity of the sample environment is required. This system allows the relative humidity to be controlled according to a pre-programmed set of instructions and alleviates some of the common problems that are encountered with conventional methods that require the use of saturated salt solutions. The system is currently installed on instrument D19 at the Institut Laue–Langevin, Grenoble. Results illustrating the application of these facilities in high-angle fibre diffraction studies of DNA are presented.