Exercise-based cardiac rehabilitation increases daily physical activity of patients following myocardial infarction: subanalysis of two randomised controlled trials

OBJECTIVE

To assess the effects of an exercise-based cardiac rehabilitation programme on daily physical activity levels of patients following myocardial infarction.

DESIGN

Subanalysis of two randomised, prospective controlled trials.

SETTING

Outpatient clinic of a secondary hospital.

PARTICIPANTS

Fifty consecutive patients randomised to the exercise group {n=25; 23 males; mean age 54 [standard deviation (SD) 9] years} or the control group [n=25; 20 males; mean age 58 (SD 9) years].

INTERVENTIONS

The exercise group participated in an 8-week aerobic exercise programme plus usual medical care and follow-up. The control group received usual medical care and follow-up.

MAIN OUTCOME MEASURES

The primary outcome measure was change in time spent undertaking moderate-to-vigorous physical activity per day, assessed by accelerometer over 7 consecutive days. Secondary outcome measures were cardiorespiratory fitness, body mass, and resting blood pressure and heart rate.

RESULTS

Moderate-to-vigorous physical activity levels increased significantly in the exercise group [43.2 (SD 36.3) to 53.5 (SD 31.9) minutes/day, P=0.030], and remained unchanged in the control group [40.8 (SD 26.2) to 36.8 (SD 26.5) minutes/day, P=0.241] from baseline to the end of the programme. Cardiorespiratory fitness increased significantly in the exercise group (mean difference 2.8; 95% of the difference 1.3 to 4.4ml/kg/minute, P=0.001) after the 8-week programme.

CONCLUSIONS

In patients under optimal medication following myocardial infarction, participation in an 8-week exercise-based cardiac rehabilitation programme was found to improve physical activity levels consistent with health-related benefits. Future studies are needed to determine whether the increase in physical activity is maintained in the long term.

Development and evaluation of a loop-mediated isothermal amplification assay for detection of Ehrlichia canis DNA in naturally infected dogs using the p30 gene

Canine monocytic ehrlichiosis (CME) is a common tick-borne disease caused by the rickettsial bacterium Ehrlichia canis (Rickettsiales: Anaplasmataceae). In view of the different stages and variable clinical signs of CME, which can overlap with those of other infections, a conclusive diagnosis can more readily be obtained by combining clinical and hematological evaluations with molecular diagnostic methods. In this study, a loop-mediated isothermal amplification (LAMP) assay targeting the p30 gene of E. canis was developed. The assay was developed using DNA extracted from E. canis-infected cultures of the macrophage cell line DH82 and samples from dogs testing positive for E. canis DNA by PCR. The LAMP assay was compared to a p30-based PCR assay, using DNA extracted from EDTA-anticoagulated blood samples of 137 dogs from an endemic region in Brazil. The LAMP assay was sensitive enough to detect a single copy of the target gene, and identified 74 (54.0%) E. canis DNA-positive samples, while the p30 PCR assay detected 50 positive samples (36.5%) among the field samples. Agreement between the two assays was observed in 42 positive and 55 negative samples. However, 32 positive samples that were not detected by the PCR assay were identified by the LAMP assay, while eight samples identified as E. canis-positive by PCR showed negative results in LAMP. The developed E. canis LAMP assay showed the potential to maximize the use of nucleic acid tests in a veterinary clinical laboratory, and to improve the diagnosis of CME.

NAG-1/GDF15 accumulates in the nucleus and modulates transcriptional regulation of the Smad pathway

Protein dynamics, modifications, and trafficking are all processes that can modulate protein activity. Accumulating evidence strongly suggests that many proteins play distinctive roles dependent on cellular location. Nonsteroidal anti-inflammatory drug activated gene-1 (NAG-1) is a TGF-β superfamily protein that plays a role in cancer, obesity, and inflammation. NAG-1 is synthesized and cleaved into a mature peptide, which is ultimately secreted into the extracellular matrix (ECM). In this study, we have found that full-length NAG-1 is expressed in not only the cytoplasm and ECM, but also in the nucleus. NAG-1 is dynamically moved to the nucleus, exported into cytoplasm, and further transported into the ECM. We have also found that nuclear NAG-1 contributes to inhibition of the Smad pathway by interrupting the Smad complex. Overall, our study indicates that NAG-1 is localized in the nucleus and provides new evidence that NAG-1 controls transcriptional regulation in the Smad pathway.