Effect of Bone Marrow Mesenchymal Stem Cells on Satellite Cell Proliferation and Apoptosis in Immobilization-Induced Muscle Atrophy in Rats.

BACKGROUND Muscle atrophy due to disuse occurs along with adverse physiological and functional changes, but bone marrow stromal cells (MSCs) may be able to act as muscle satellite cells to restore myofibers. Thus, we investigated whether MSCs could enhance the proliferation of satellite cells and suppress myonuclear apoptosis during immobilization. MATERIAL AND METHODS We isolated, purified, amplified, and identified MSCs. Rats (n=48) were randomized into 3 groups: WB group (n=16), IM-PBS group (n=16), and IM-MSC (n=16). Rat hind limbs were immobilized for 14 d, treated with MSCs or phosphate-buffered saline (PBS), and then studied using immunohistochemistry and Western blot analysis to characterize the proteins involved. Apoptosis was assessed by terminal deoxynucleotidyl transferase (TdT)-mediated deoxy-UTP nick end labeling (TUNEL) method. RESULTS We compared muscle mass, cross-sectional areas, and peak tetanic forces and noted insignificant differences between PBS- and MSC-treated animals, but satellite cell proliferation was significantly greater after MSC treatment (p<0.05). Apoptotic myonuclei were reduced (p<0.05) after MSC treatment as well. Pro-apoptotic Bax was down-regulated and anti-apoptotic Bcl-2 and p-Akt protein were upregulated (p<0.05). CONCLUSIONS MSCs injected during hind limb immobilization can maintain satellite cell activity by suppressing myonuclear apoptosis.

Quantized Output-Feedback Control for Unmanned Marine Vehicles With Thruster Faults via Sliding-Mode Technique.

This article is concerned with the quantized output-feedback control problem for unmanned marine vehicles (UMVs) with thruster faults and ocean environment disturbances via a sliding-mode technique. First, based on output information and compensator states, an augmented sliding surface is constructed and sliding-mode stability through linear matrix inequalities can be guaranteed. An improved quantization parameter dynamic adjustment scheme, with a larger quantization parameter adjustment range, is then given to compensate for quantization errors effectively. Combining the quantization parameter adjustment strategy and adaptive mechanism, a novel robust sliding-mode controller is designed to guarantee the asymptotic stability of a closed-loop UMV system. As a result, a smaller lower bound of the thruster fault factor than that of the existing result can be tolerated, which brings more practical applications. Finally, the comparison simulation results have illustrated the effectiveness of the proposed method.

Exercise for Neuropathic Pain: A Systematic Review and Expert Consensus.

Background: Neuropathic pain (NP), a severe and disruptive symptom following many diseases, normally restricts patients' physical functions and leads to anxiety and depression. As an economical and effective therapy, exercise may be helpful in NP management. However, few guidelines and reviews focused on exercise therapy for NP associated with specific diseases. The study aimed to summarize the effectiveness and efficacy of exercise for various diseases with NP supported by evidence, describe expert recommendations for NP from different causes, and inform policymakers of the guidelines. Design: A systematic review and expert consensus. Methods: A systematic search was conducted in PubMed. We included systematic review and meta-analysis, randomized controlled trials (RCTs), which assessed patients with NP. Studies involved exercise intervention and outcome included pain intensity at least. Physiotherapy Evidence Database and the Assessment of Multiple Systematic reviews tool were used to grade the quality assessment of the included RCTs and systematic reviews, respectively. The final grades of recommendation were based on strength of evidence and a consensus discussion of results of Delphi rounds by the Delphi consensus panel including 21 experts from the Chinese Association of Rehabilitation Medicine. Results: Eight systematic reviews and 21 RCTs fulfilled all of the inclusion criteria and were included, which were used to create the 10 evidence-based consensus statements. The 10 expert recommendations regarding exercise for NP symptoms were relevant to the following 10 different diseases: spinal cord injury, stroke, multiple sclerosis, Parkinson's disease, cervical radiculopathy, sciatica, diabetic neuropathy, chemotherapy-induced peripheral neuropathy, HIV/AIDS, and surgery, respectively. The exercise recommended in the expert consensus involved but was not limited to muscle stretching, strengthening/resistance exercise, aerobic exercise, motor control/stabilization training and mind-body exercise (Tai Chi and yoga). Conclusions: Based on the available evidence, exercise is helpful to alleviate NP intensity. Therefore, these expert consensuses recommend that proper exercise programs can be considered as an effective alternative treatment or complementary therapy for most patients with NP. The expert consensus provided medical staff and policymakers with applicable recommendations for the formulation of exercise prescription for NP. This consensus statement will require regular updates after five-ten years.

English vowels produced by Cantonese-English bilingual speakers.

The present study attempted to test the postulate that sounds of a foreign language that are familiar can be produced with less accuracy than sounds that are new to second language (L2) learners. The first two formant frequencies (F1 and F2) were obtained from the 11 English monophthong vowels produced by 40 Cantonese-English (CE) bilingual and 40 native American English monolingual speakers. Based on F1 and F2, compact-diffuse (C-D) and grave-acute (G-A) values, and Euclidean Distance (ED) associated with the English vowels were evaluated and correlated with the perceived amount of accent present in the vowels. Results indicated that both male and female CE speakers exhibited different vowel spaces compared to their AE counterparts. While C-D and G-A indicated that acquisition of familiar and new vowels were not particularly different, ED values suggested better performance in CE speakers' productions of familiar vowels over new vowels. In conclusion, analyses based on spectral measurements obtained from the English vowel sounds produced by CE speakers did not provide favourable evidence to support the Speech Learning Model (SLM) proposed by Flege (1995) . Nevertheless, for both familiar and new sounds, English back vowels were found to be produced with greater inaccuracy than English front vowels.

Adaptive neural output feedback controller design with reduced-order observer for a class of uncertain nonlinear SISO systems.

An adaptive output feedback control is studied for uncertain nonlinear single-input-single-output systems with partial unmeasured states. In the scheme, a reduced-order observer (ROO) is designed to estimate those unmeasured states. By employing radial basis function neural networks and incorporating the ROO into a new backstepping design, an adaptive output feedback controller is constructively developed. A prominent advantage is its ability to balance the control action between the state feedback and the output feedback. In addition, the scheme can be still implemented when all the states are not available. The stability of the closed-loop system is guaranteed in the sense that all the signals are semiglobal uniformly ultimately bounded and the system output tracks the reference signal to a bounded compact set. A simulation example is given to validate the effectiveness of the proposed scheme.

A DSC approach to robust adaptive NN tracking control for strict-feedback nonlinear systems.

A robust adaptive tracking control approach is presented for a class of strict-feedback single-input-single-output nonlinear systems. By employing radial-basis-function neural networks to account for system uncertainties, the proposed scheme is developed by combining "dynamic surface control" and "minimal learning parameter" techniques. The key features of the algorithm are that, first, the problem of "explosion of complexity" inherent in the conventional backstepping method is avoided, second, the number of parameters updated online for each subsystem is reduced to 2, and, third, the possible controller singularity problem in the approximation-based adaptive control schemes with feedback linearization technique is removed. These features result in a much simpler adaptive control algorithm, which is convenient to implement in applications. In addition, it is shown via input-to-state stability theory and small gain approach that all signals in the closed-loop system are semiglobal uniformly ultimately bounded. Finally, three simulation examples are used to demonstrate the effectiveness of the proposed scheme.