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Background Doxorubicin, a widely used anti-tumour drug, is known to cause muscle loss in cancer patients. Methods Following an acute dose of doxorubicin injection (2.5 mg/kg per body weight), we examined macrophage distribution in rat soleus muscle challenged by eccentric exercise (downhill running). Long-term doxorubicin treatment (one injection every 3 days) on muscle mass and survival were also determined. Results Under non-exercised condition, increased tumour necrosis factor (TNF)-alpha mRNA and decreased IL-10 mRNA were observed in soleus muscle of doxorubicin-treated rats, compared with saline-treated control rats. However, increases in inflammation score (leukocyte infiltration), nitrotyrosine level, and M1 macrophage (CD68+) invasion in exercised soleus muscle were absent in doxorubicin-treated rats, whereas increased M2 macrophage (CD163+) localization in exercised muscle was less affected by doxorubicin. Despites coenzyme Q (Q10) supplementation significantly elevated TNF-alpha mRNA, nitrotyrosine, and anti-oxidant gamma-glutamylcysteine synthetase (GCS) levels in non-exercised soleus muscle, these pro-inflammatory responses were also abolished in doxorubicin-treated rats. Results from long-term doxorubicin treatment show a significant muscle loss followed by an accelerated death, which cannot be reversed by Q10 supplementation. Conclusions (i) Doxorubicin impairs inflammation mechanism by depleting M1 macrophage in exercised skeletal muscle; (ii) Muscle loss and accelerated death during prolonged doxorubicin treatment cannot be reversed by Q10 supplementation.

To quantify changes of elbow spasticity over time after botulinum toxin type A (BTX-A) injection in the upper extremity of stroke patients.Before-after trial in which the therapeutic effects were followed up at 2, 6, and 9 weeks after the BTX-A injection (Botox).Hospital.Chronic stroke patients (N=8) with upper-limb spasticity.BTX-A was injected in upper-limb muscles, including the biceps brachii.Treatment effects were quantified as the changes in the velocity and the length dependence of hyperexcitable stretch reflexes. Manual sinusoid stretches of the elbow joint at 4 frequencies (1/3, 1/2, 1, 3/2Hz) over a movement range of 60 degrees were performed on patients by using a portable device. The Modified Ashworth Scale (MAS), biomechanic viscosity, and the reflexive electromyography threshold (RET) of the biceps brachii were used to evaluate the degree of hypertonia.The statistical analyses of the MAS score, biomechanic viscosity, and RET revealed a significant decrease in spasticity after the injection (all P.05). Moreover, our quantitative parameters (biomechanic viscosity, RET) revealed small changes in spasticity after the BTX-A injection that could not be observed from clinical MAS evaluations. Five of 8 subjects showed a maximal reduction in spasticity (in terms of biomechanic viscosity value) within 6 weeks after the injection, whereas it was notable that all subjects exhibited peak RET values at either 2 or 6 weeks after the injection with variable degrees of relapse of spasticity.Early relapse of spasticity (within 9 weeks of the injection) can be detected from biomechanic and neurophysiologic assessments in a clinical setup. These quantitative indices provide valuable information for clinicians when making decisions to perform additional rehabilitation interventions or another BTX-A injection in the early stages of treatment.

This paper propose a six degree-of-freedom (DOF) compact positioner with high resolution and large travel range for the manufacture of injection molded part application. The precise positioner is composed of monolithic parallel flexure mechanism, horizontal and vertical electromagnetic actuators, and optical displacement sensors to achieve the 6-DOF motion. The concept of the system intends to achieve three goals: 1) large travel range, 2) high precision positioning, and 3) fast response. In our system, there are eight sets of permanent magnets attached to the moving platform, and eight sets of electromagnets mounted on the bottom platen. The whole control architecture is to take the six posture data measured by the six optical displacement sensors first and then to control the 6-DOF motion by regulating the current in the electromagnetic actuators. For the purpose of system robustness and stability, an adaptive sliding-mode controller is proposed to validate the system performance. The developed robust adaptive control architecture consists of two components: 1) sliding mode controller, 2) adaptive law. From the simulation and experimental results, satisfactory performances of the hereby developed system, including stiffness and precision, have been successfully demonstrated.

Chen J-JJ, Wu Y-N, Huang S-C, Lee H-M, Wang Y-L. The use of a portable muscle tone measurement device to measure the effects of botulinum toxin type A on elbow flexor spasticity. Objective To use a portable muscle tone assessment device to measure spasticity after a botulinum toxin type A (BTX-A) injection. Design Before-after trial. Setting Hospital. Participants Ten chronic stroke patients with upper-limb spasticity. Intervention BTX-A was injected in the biceps brachii. Main Outcome Measures The biomechanic parameters, viscous component, and averaged viscosity derived from the acquired reactive resistance and angular displacements, as well as the reflex electromyographic threshold of biceps brachii, were used for spasticity evaluation. Results A statistically significant decrease in averaged viscosity and a significant increase in reflex electromyographic threshold ( P Conclusions Our portable design allows for the convenient use of the device for quantifying spasticity in clinics. All quantitative measurements suggest that BTX-A decreases spasticity within 2 weeks of injection. Our portable muscle tone measurement device may be useful for the clinical assessment of elbow flexor spasticity.