The effect of motor imagery on quality of movement when performing reaching tasks in healthy subjects: A proof of concept

IntroductionThe use of motor imagery (MI) has been shown to offer significant improvements in movement performance in sports, and is now receiving a lot of attention as a relatively new therapeutic approach which can be applied in rehabilitation. However, the effects of MI on the quality of movement is still unclear. This study explored the immediate effect of MI on reaching tasks in healthy subjects.Methods17 healthy individuals (33 ± 8.2 years) participated in the study. Surface electromyography (sEMG) and inertial measurement units (IMU) were used to identify muscle activity and angular velocity in both upper limbs. Participants performed a reach task using their dominant and non-dominant arms at their most comfortable speed, they were then asked to imagine themselves performing the same reaching task, and finally they were asked to repeat the reaching task.ResultsSignificant decreases were seen in the muscle activity between pre and post MI for Biceps Brachii, Anterior Deltoid and Triceps Brachii. In addition, a significant increase was seen in extension angular velocity post MI.DiscussionThe results indicate that the use of MI just after physical practice appears to have an immediate effect on the muscle activity and kinematics during a reaching task, which may suggest an improved quality of movement.ConclusionThis proof of concept study shows the potential for MI to improve the quality of performing reaching task and offers a possible therapeutic option for Stroke survivors and other neuromuscular disorders.     

Awareness of major cardiovascular risk factors and its relationship with markers of vascular aging: Data from the Brisighella Heart Study

Background and aimGeneral population awareness about cardiovascular risk factors is usually low. The aim of the present study was to evaluate the vascular aging of subjects aware and not aware to be hypertensive, hypercholesterolemic, hypertriglyceridemic or diabetics in a general population sample.Methods and resultsWe interviewed 1652 subjects without atherosclerotic cardiovascular diseases (M: 46.6%, F: 53.4%) about their awareness of hypertension, hypercholesterolemia, hypertriglyceridemia or type 2 diabetes. Then we compared the augmentation index and pulse wave velocity of subjects aware and not aware of the investigated cardiovascular risk factors. 1049 participants declared not to be hypertensive, while 32 were not sure. Among them, respectively, 23.5% and 50% were hypertensive. Subjects not aware of their hypertension had significantly higher aortic blood pressure than aware ones (p < 0.001). 841 participants declared not to be hypercholesterolemic, while 60 were not sure. Among them, respectively, 18.1% and 40% were hypercholesterolemic. Subjects not aware of their hypercholesterolemia had significantly higher augmentation index than the aware ones (p < 0.05). 1226 participants declared not to be hypertriglyceridemic, while 200 were not sure. Among them, respectively, 19.2% and 44% were hypertriglyceridemic. Subjects not aware of their hypertriglyceridemia had significantly higher TG levels aware ones (p < 0.05), although this seemed to not related to increased arterial stiffness. 1472 participants declared not to be diabetic, while 20 were not sure. Among them, respectively, 2.0% and 25.0% were diabetics. Subjects not aware of their diabetes had significantly higher augmentation index than the aware ones (p < 0.05).ConclusionsIn conclusion, the lack of awareness of hypertension and hypercholesterolemia is relatively frequent in the general population and is associated to significantly higher arterial stiffness.     

Visualization of electrophysiological activity at the carpal tunnel area using magnetoneurography

ObjectiveTo establish a noninvasive method to measure the neuromagnetic fields of the median nerve at the carpal tunnel after electrical digital nerve stimulation and evaluate peripheral nerve function.MethodsUsing a vector-type biomagnetometer system with a superconducting quantum interference device, neuromagnetic fields at the carpal tunnel were recorded after electrical stimulation of the index or middle digital nerve in five healthy volunteers. A novel technique for removing stimulus-induced artifacts was applied, and current distributions were calculated using a spatial filter algorithm and superimposed on X-ray.ResultsA neuromagnetic field propagating from the palm to the carpal tunnel was observed in all participants. Current distributions estimated from the magnetic fields had five components: leading and trailing components parallel to the conduction pathway, outward current preceding the leading component, inward currents between the leading and trailing components, and outward current following the trailing component. The conduction velocity and peak latency of the inward current agreed well with those of sensory nerve action potentials.ConclusionRemoving stimulus-induced artifacts enabled magnetoneurography to noninvasively visualize with high spatial resolution the electrophysiological neural activity from the palm to the carpal tunnel.SignificanceThis is the first report of using magnetoneurography to visualize electrophysiological nerve activity at the palm and carpal tunnel.     

中西医联合治疗糖尿病周围神经病变效果观察

目的研究中西医联合治疗糖尿病周围神经病变患者的临床效果。方法按照随机数字表法将2017年7月-2018年6月期间本院收治的72例糖尿病周围神经病变患者分为两组,对照组36例采用常规西医治疗,观察组36例采用中西医联合治疗。将两组的神经传导速度、临床疗效、用药安全性进行比对。结果观察组糖尿病周围神经病变患者治疗后正中神经、尺神经的MNCV、SNCV均快于对照组,临床总有效率高于对照组,P<0.05;两组的不良反应发生率进行比较差异无统计学意义,P>0.05。结论中西医联合治疗糖尿病周围神经病变患者具有较高的有效性和安全性。     

Measuring conduction velocity distributions in peripheral nerves using neurophysiological techniques

ObjectiveTo determine how long it takes for neural impulses to travel along peripheral nerve fibers in living humans.MethodsA collision test was performed to measure the conduction velocity distribution of the ulnar nerve. Two stimuli at the distal and proximal sites were used to produce the collision. Compound muscle or nerve action potentials were recorded to perform the measurements on the motor or mixed nerve, respectively. Interstimulus interval was set at 1–5 ms. A quadri-pulse technique was used to measure the refractory period and calibrate the conduction time.ResultsCompound muscle action potential produced by the proximal stimulation started to emerge at the interstimulus interval of about 1.5 ms and increased with the increment in interstimulus interval. Two groups of motor nerve fibers with different conduction velocities were identified. The mixed nerve showed a wider conduction velocity distribution with identification of more subgroups of nerve fibers than the motor nerve.ConclusionsThe conduction velocity distributions in high resolution on a peripheral motor and mixed nerve are different and this can be measured with the collision test.SignificanceWe provided ground truth data to verify the neuroimaging pipelines for the measurements of latency connectome in the peripheral nervous system.     

冠心康方加减联合西药治疗冠心病合并2型糖尿病气虚痰瘀证疗效研究

目的:探讨冠心康方加减联合西药治疗冠心病合并2型糖尿病气虚痰瘀证的疗效。方法:选择冠心病合并2型糖尿病患者98例,按随机数字表法分为对照组47例和观察组51例。对照组给予西医常规治疗措施; 观察组在对照组治疗基础上加用冠心康方加减治疗,1剂/次,2 次/d。连续治疗6个月后,比较两组血糖血脂水平、中医证候评分、脉搏波传导速度(PWV)以及临床疗效。结果:治疗后,观察组的空腹血糖(6.71±1.04)mmol/L、餐后2 h血糖为(10.63±1.94)mmol/L、HbA1c(7.13±0.97)%、TG(2.50±0.40)mmol/L,TC(3.94±0.55)mmol/L均低于对照组[(6.89±1.13)mmol/L、(10.93±2.03)mmol/L、(7.22±1.25)%、(2.53±0.36)mmol/L、(4.01±0.53)mmol/L],两组间比较差异有统计学意义(P<0.05)。治疗后观察组HDL-C(1.23±0.22)mmol/L 与对照组(1.19±0.21)mmol/L比较上升,而观察组LDL-C(2.61±0.34)mmol/L比对照组(2.67±0.37)mmol/L下降,组间比较差异无统计学意义(P>0.05)。治疗后,观察组患者中医证候评分(1.76±0.27)分及BS-PWV(5.90±0.64)m/s、ES-PWV(7.59±0.94)m/s均明显低于对照组的[(2.13±0.31)分、(6.41±0.77)m/s、(8.43±1.31)m/s](P<0.05)。观察组和对照组的总有效率分别为70.59%和59.57%,两组比较差异有统计学意义(P<0.05)。结论:冠心康方加减联合西药治疗冠心病合并2型糖尿病气虚痰瘀证可有效改善患者的血糖、血脂、中医证候以及动脉硬化,提高临床疗效。     

Motion‐compensated b‐tensor encoding for in vivo cardiac diffusion‐weighted imaging

Motion is a major confound in diffusion‐weighted imaging (DWI) in the body, and it is a common cause of image artefacts. The effects are particularly severe in cardiac applications, due to the nonrigid cyclical deformation of the myocardium. Spin echo‐based DWI commonly employs gradient moment‐nulling techniques to desensitise the acquisition to velocity and acceleration, ie, nulling gradient moments up to the 2nd order (M2‐nulled). However, current M2‐nulled DWI scans are limited to encode diffusion along a single direction at a time. We propose a method for designing b‐tensors of arbitrary shapes, including planar, spherical, prolate and oblate tensors, while nulling gradient moments up to the 2nd order and beyond. The design strategy comprises initialising the diffusion encoding gradients in two encoding blocks about the refocusing pulse, followed by appropriate scaling and rotation, which further enables nulling undesired effects of concomitant gradients. Proof‐of‐concept assessment of in vivo mean diffusivity (MD) was performed using linear and spherical tensor encoding (LTE and STE, respectively) in the hearts of five healthy volunteers. The results of the M2‐nulled STE showed that (a) the sequence was robust to cardiac motion, and (b) MD was higher than that acquired using standard M2‐nulled LTE, where diffusion‐weighting was applied in three orthogonal directions, which may be attributed to the presence of restricted diffusion and microscopic diffusion anisotropy. Provided adequate signal‐to‐noise ratio, STE could significantly shorten estimation of MD compared with the conventional LTE approach. Importantly, our theoretical analysis and the proposed gradient waveform design may be useful in microstructure imaging beyond diffusion tensor imaging where the effects of motion must be suppressed.