Role of exosomes and exosomal microRNA in muscle–Kidney crosstalk in chronic kidney disease

Chronic kidney disease (CKD) is a progressive damage of kidneys that can no longer serve the blood-filtering function, and is a life-threatening condition. Skeletal muscle wasting is a common complication of CKD. Yet the relationship between kidney and skeletal muscle in CKD remains unclear. Exosomes, a type of small membrane-bound vesicles released from cells to the extracellular environment, have increasingly received attention due to their potential as mediators of crosstalk between kidneys and different organs, including skeletal muscle. This mini-review summarizes the recent findings that point to the role of exosomes in the cross-talk between kidney and skeletal muscle in CKD. Understanding of the contents and the mechanism of exosome release may prone exosomes be the potential therapeutic targets for CKD.

Indentation Stiffness Measurement by an Optical Coherence Tomography-Based Air-Jet Indentation System Can Reflect Type I Collagen Abundance and Organisation in Diabetic Wounds

There is a lack of quantitative and non-invasive clinical biomechanical assessment tools for diabetic foot ulcers. Our previous study reported that the indentation stiffness measured by an optical coherence tomography-based air-jet indentation system in a non-contact and non-invasive manner may reflect the tensile properties of diabetic wounds. As the tensile properties are known to be contributed by type I collagen, this study was aimed to establish the correlations between the indentation stiffness, and type I collagen abundance and organisation, in order to further justify and characterise the in vivo indentation stiffness measurement in diabetic wounds. In a male streptozotocin-induced diabetic rat model, indentation stiffness, and type I collagen abundance and organisation of excisional wounds were quantified and examined using the optical coherence tomography-based air-jet indentation system and picrosirius red polarised light microscopy, respectively, on post-wounding days 3, 5, 7, 10, 14, and 21. The results showed significant negative correlations between indentation stiffness at the wound centre, and the collagen abundance and organisation. The correlations between the indentation stiffness, as well as collagen abundance and organisation of diabetic wounds suggest that the optical coherence tomography-based air-jet indentation system can potentially be used to quantitatively and non-invasively monitor diabetic wound healing in clinical settings, clinical research or preclinical research.

Effect of EMG-biofeedback robotic-assisted body weight supported treadmill training on walking ability and cardiopulmonary function on people with subacute spinal cord injuries - a randomized controlled trial

BACKGROUND

Body weight supported treadmill training (BWSTT) is a frequently used approach for restoring the ability to walk after spinal cord injury (SCI). However, the duration of BWSTT is usually limited by fatigue of the therapists and patients. Robotic-assisted body weight supported treadmill training (RABWSTT) was developed to tackle the aforesaid limitation. Currently, limited randomized controlled trials are available to investigate its effectiveness, especially on cardiopulmonary function. The aim of this two-arm, parallel-group randomized controlled trial is to examine the feasibility of adapting an EMG-biofeedback system for assist-as-needed RABWSTT and its effects on walking and cardiopulmonary function in people with SCI.

METHODS

Sixteen incomplete SCI subjects were recruited and randomly allocated into an intervention group or control group. The intervention group received 30 min of RABWSTT with EMG biofeedback system over the vastus lateralis muscle to enhance active participation. Dose equivalent passive lower limbs mobilization exercise was provided to subjects in the control group.

RESULTS

Significant time-group interaction was found in the Walking Index for Spinal Cord Injury version II (WISCI II) (p = 0.020), Spinal Cord Independence Measure version III (SCIM III) mobility sub-score (p < 0.001), bilateral symmetry (p = 0.048), maximal oxygen consumption (p = 0.014) and peak expiratory flow rate (p = 0.048). Wilcoxon signed-rank test showed that the intervention group had significant improvement in the above-mentioned outcomes after the intervention except WISCI II, which also yielded marginal significance level.

CONCLUSION

The present study demonstrated that the use of EMG-biofeedback RABWSTT enhanced the walking performance for SCI subjects and improve cardiopulmonary function. Positive outcomes reflect that RABSTT training may be able to enhance their physical fitness.

TRIAL REGISTRATION

The study protocol was approved by the Research Ethics Committee (Kowloon Central/ Kowloon East), Hospital Authority on 6 December 2013, and the Human Subjects Ethics Sub-committee of The Hong Kong Polytechnic University on 15 May 2013, with reference numbers KC/KC-13-0181/ER-2 and HSEARS20130510002 respectively. The study was registered in ClinicalTrials.gov on 20 November 2013, with reference number NCT01989806 .).

Transcutaneous Electrical Nerve Stimulation for Neuropathic Pain

This study examined the clinical effectiveness of high-frequency transcutaneous electrical nerve stimulation for reducing hypersensitivity of the hand. Nineteen patients suffering from hand hypersensitivity were randomly assigned into either a treatment or a placebo group. A visual analogue scale and the Downey Hand Centre Hand Sensitivity Test were used to measure the tactile tolerance of the hand. Grip strength was assessed by a grip dynamometer. Daily applications of electrical stimulation were provided for 2 weeks. Significantly lower pain scores were found in the treatment group than in the placebo group by Day 7 and Day 11. The ranking of ten dowel textures of the Downey Hand Centre Hand Sensitivity Test in the treatment group was significantly higher than in the placebo group by Day 7 and Day 11. However, no significant intergroup difference was found in grip strength.

A multidisciplinary rehabilitation programme for patients with chronic low back pain: a prospective study

PURPOSE

To examine the effectiveness of a multidisciplinary rehabilitation programme for patients with chronic low back pain in Hong Kong, and to identify factors associated with work resumption.

METHODS

57 men and 8 women aged 20 to 56 (mean, 39) years who had a more than 3-month history of low back pain and were unresponsive to more than 6 months of conventional treatment participated in a 14-week multidisciplinary rehabilitation programme involving physical conditioning, work conditioning, and work readiness. Training protocols entailed flexibility and endurance training, hydrotherapy, weight lifting, and work stimulation. Patients were assessed at baseline (week 1), week 7, week 14, and month 6 with regard to the intensity of low back pain, self-perceived disability, range of lumbar motion, isoinertial performance of the trunk muscles, and depression level. Patient demographics that influenced work resumption were identified using a prediction model. Patients who did and did not return to work were compared.

RESULTS

Of the 54 patients who completed all follow-up assessments, 28 returned to work and 26 did not. The latter was significantly older (37 vs. 42 years, p=0.038) and absent from work longer (11 vs. 22 months, p=0.029) than the former. The rehabilitation programme helped patients regain physical function and the ability to work. Patients who returned to work showed greater improvement in self-perceived disability and physical function.

CONCLUSION

This rehabilitation programme facilitated regain of physical functioning and the ability to return to work. The pre-programme employment status, duration of absence from work, and patient age were the most important predictors for work resumption.