[Study on safe depth of needling at acupoints of kidney regions based on MRI imaging].

OBJECTIVE: To measure the dangerous depth and the effective safe depth of needling at acupoints of kidney regions based on MRI imaging, and to provide the imaging support for clinical practice. METHODS: The abdominal enhanced T1 MRI imaging of horizontal plane of 61 healthy subjects was included, the anatomical structure of bilateral Weishu (BL 21), Sanjiaoshu (BL 22), Shenshu (BL 23), Weicang (BL 50), Huangmen (BL 51) and Zhishi (BL 52) was analyzed, and the dangerous depth and effective safe depth of perpendicular and oblique needling were measured between the left and right sides and subjects with different body sizes. RESULTS: There were no significant differences between dangerous depth and effective safe depth of perpendicular and oblique needling at bilateral acupoints of kidney region (P>0.05). The dangerous depth and effective safe depth of perpendicular and oblique needling at bilateral acupoints of kidney region in the moderate group were larger than the underweight group (P<0.05), while those in the overweight group were larger than the moderate group and the underweight group (P<0.05). CONCLUSION: The safe depth of needling at acupoints of kidney region is related to body size, for moderate weight and overweight patients, the needling depth could be increased for better efficacy, while for underweight patients, the recommend direction and depth of needling should be restricted to avoid acupuncture accident.

Multi-shot Diffusion-Weighted MRI With Multiplexed Sensitivity Encoding (MUSE) in the Assessment of Active Inflammation in Crohn's Disease.

BACKGROUND: Single-shot diffusion-weighted imaging (ssDWI) has been shown useful for detecting active bowel inflammation in Crohn's disease (CD) without MRI contrast. However, ssDWI suffers from geometric distortion and low spatial resolution. PURPOSE: To compare conventional ssDWI with higher-resolution ssDWI (HR-ssDWI) and multi-shot DWI based on multiplexed sensitivity encoding (MUSE-DWI) for evaluating bowel inflammation in CD, using contrast-enhanced MR imaging (CE-MRI) as the reference standard. STUDY TYPE: Prospective. SUBJECTS: Eighty nine patients with histological diagnosis of CD from previous endoscopy (55 male/34 female, age: 17-69 years). FIELD STRENGTH/SEQUENCES: ssDWI (2.7 mm × 2.7 mm), HR-ssDWI (1.8 mm × 1.8 mm), MUSE-DWI (1.8 mm × 1.8 mm) based on echo-planar imaging, T2-weighted imaging, and CE-MRI sequences, all at 1.5 T. ASSESSMENT: Five raters independently evaluated the tissue texture conspicuity, geometry accuracy, minimization of artifacts, diagnostic confidence, and overall image quality using 5-point Likert scales. The diagnostic performance (sensitivity, specificity and accuracy) of each DWI sequences was assessed on per-bowel-segment basis. STATISTICAL TESTS: Inter-rater agreement for qualitative evaluation of each parameter was measured by the intra-class correlation coefficient (ICC). Paired Wilcoxon signed-rank tests were performed to evaluate the statistical significance of differences in qualitative scoring between DWI sequences. A P value <0.05 was considered to be statistically significant. RESULTS: Tissue texture conspicuity, geometric distortions, and overall image quality were significantly better for MUSE-DWI than for ssDWI and HR-ssDWI with good agreement among five raters (ICC: 0.70-0.89). HR-ssDWI showed significantly poorer performance to ssDWI and MUSE-DWI for all qualitative scores and had the worst diagnostic performance (sensitivity of 57.0% and accuracy of 87.3%, with 36 undiagnosable cases due to severe artifacts). MUSE-DWI showed significantly higher sensitivity (97.5% vs. 86.1%) and accuracy (98.9% vs. 95.1%) than ssDWI for detecting bowel inflammation. DATA CONCLUSION: MUSE-DWI was advantageous in assessing bowel inflammation in CD, resulting in improved spatial resolution and image quality. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 2.

Speed-adaptive control of functional electrical stimulation for dropfoot correction.

BACKGROUND: Functional electrical stimulation is an important therapy technique for dropfoot correction. In order to achieve natural control, the parameter setting of FES should be associated with the activation of the tibialis anterior. METHODS: This study recruited nine healthy subjects and investigated the relations of walking speed with the onset timing and duration of tibialis anterior activation. Linear models were built for the walking speed with respect to these two parameters. Based on these models, the speed-adaptive onset timing and duration were applied in FES-assisted walking for nine healthy subjects and ten subjects with dropfoot. The kinematic performance of FES-assisted walking triggered by speed-adaptive stimulation were compared with those triggered by the heel-off event, and no-stimulation walking at different walking speeds. RESULTS: Higher ankle dorsiflexion angle was observed in heel-off stimulation and speed-adaptive stimulation conditions than that in no-stimulation walking condition at all the speeds. For subjects with stroke, the ankle plantarflexion angle in speed-adaptive stimulation condition was similar to that in no-stimulation walking condition, and it was significant larger than that in heel-off stimulation condition at all speeds. CONCLUSIONS: The improvement in ankle dorsiflexion without worsening ankle plantarflexion in speed-adaptive stimulation condition could be attributed to the appropriate stimulation timing and duration. These results provide evidence that the proposed stimulation system with speed-related parameters is more physiologically appropriate in dropfoot correction, and it may have great potential value in future clinical applications. TRIAL REGISTRATION: Medical Ethics Committee of Guangdong Work Injury Rehabilitation Center, AF/SC-07/2016.22 . Registered 26 May 2016.

Intensity- and Duration-Adaptive Functional Electrical Stimulation Using Fuzzy Logic Control and a Linear Model for Dropfoot Correction.

Functional electrical stimulation (FES) is important in gait rehabilitation for patients with dropfoot. Since there are time-varying velocities during FES-assisted walking, it is difficult to achieve a good movement performance during walking. To account for the time-varying walking velocities, seven poststroke subjects were recruited and fuzzy logic control and a linear model were applied in FES-assisted walking to enable intensity- and duration-adaptive stimulation (IDAS) for poststroke subjects with dropfoot. In this study, the performance of IDAS was evaluated using kinematic data, and was compared with the performance under no stimulation (NS), FES-assisted walking triggered by heel-off stimulation (HOS), and speed-adaptive stimulation. A larger maximum ankle dorsiflexion angle in the IDAS condition than those in other conditions was observed. The ankle plantar flexion angle in the IDAS condition was similar to that of normal walking. Improvement in the maximum ankle dorsiflexion and plantar flexion angles in the IDAS condition could be attributed to having the appropriate stimulation intensity and duration. In summary, the intensity- and duration-adaptive controller can attain better movement performance and may have great potential in future clinical applications.

Nonlinear disturbance observer based sliding mode control of a cable-driven rehabilitation robot.

This paper introduces a cable-driven robot for upper-limb rehabilitation. Kinematic and dynamic of this rehabilitation robot is analyzed. A sliding mode controller combined with a nonlinear disturbance observer is proposed to control this robot in the presence of disturbances. Simulation is carried out to prove the effectiveness of the proposed control scheme, and the results of the proposed controller is compared with a PID controller and a traditional sliding mode controller. Results show that the proposed controller can effectively improve the tracking performance as compared with the other two controllers and cause lower chattering as compared with a traditional sliding mode controller.

Thermoresponsive polymers based on poly-vinylpyrrolidone: applications in nanoparticle catalysis.

Two thermoresponsive polymers based on alkyl modified poly-vinylpyrrolidone (PVP) that exhibit very sensitive and reversible temperature-dependant water solubility are described. The application of these polymers as Au nanocatalyst stabilizers leads to a "smart" thermoresponsive Au nanoparticle catalyst.

Expression pattern of aquaporin 4 and 5 in the middle ear of guinea pigs with secretory otitis media.

CONCLUSIONS: Our study suggests that aquaporins 4 and 5 (AQP4 and AQP5) in the middle ear cavity may play a vital role in the homeostasis of the tubotympanum and in the course of the accumulation of the effusion in secretory otitis media (SOM). OBJECTIVE: To explore the pathological change in water homeostasis in the middle ear in SOM and to observe the expression and regulation of AQP4 and AQP5 in the middle ear cavity in SOM. MATERIALS AND METHODS: Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting were used to detect AQP4 and AQP5 in the bullae of animal models of SOM and normal animals. The expression patterns of AQP4 and AQP5 in the SOM group were compared with those in the normal group. RESULTS: RT-PCR and immunoblot analyses revealed that mRNAs encoding AQP4 and AQP5 were expressed in the middle ear membrane of the guinea pigs in both groups; AQP4 was also detected as 33 kDa protein in both groups. Quantitative analysis of RT-PCR and Western blotting revealed that expression of AQP4 and AQP5 was higher in the SOM group than in the control group.