Sevoflurane impedes glioma progression via regulating circ_0000215/miR-1200/NCR3LG1 axis.

Sevoflurane has been reported to have anti-tumorigenic effects in glioma. Circ_0000215 was found to play vital functions in the pathological progressions of glioma. However, whether circ_0000215 mediates the inhibitory effects of sevoflurane on glioma cells remains unclear. In vitro assays were performed using cell counting kit-8, flow cytometry, transwell and Western blot assays. The expression levels of circ_0000215, microRNA (miR)-1200 and NCR3LG1 (Natural Killer Cell Cytotoxicity Receptor 3 Ligand 1) were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and/or Western blot. The dual-luciferase reporter assay and pull-down assay were used to investigate the relationship between miR-1200 and circ_0000215 or NCR3LG1. In vivo assay was conducted using xenograft nude mice model. In vitro assays suggested that sevoflurane repressed glioma cell proliferation, metastasis and induced apoptosis as well as hindered tumor growth in vivo, which were reversed by circ_0000215 overexpression. Mechanically, circ_0000215 was confirmed to directly target miR-1200, and NCR3LG1 was a target of miR-1200 in glioma cells. Importantly, circ_0000215 could regulate NCR3LG1 expression via miR-1200. Besides that, rescue assay suggested that circ_0000215 attenuated the inhibitory effects of sevoflurane on glioma cell growth and metastasis, which were reversed by miR-1200 overexpression or NCR3LG1 knockdown. Our study revealed that sevoflurane could suppress glioma tumorigenesis by regulating circ_0000215/miR-1200/NCR3LG1 axis, suggesting a new insight into the therapeutic potential of sevoflurane in glioma treatment.

Comparison of sEMG-Based Feature Extraction and Motion Classification Methods for Upper-Limb Movement.

The surface electromyography (sEMG) technique is proposed for muscle activation detection and intuitive control of prostheses or robot arms. Motion recognition is widely used to map sEMG signals to the target motions. One of the main factors preventing the implementation of this kind of method for real-time applications is the unsatisfactory motion recognition rate and time consumption. The purpose of this paper is to compare eight combinations of four feature extraction methods (Root Mean Square (RMS), Detrended Fluctuation Analysis (DFA), Weight Peaks (WP), and Muscular Model (MM)) and two classifiers (Neural Networks (NN) and Support Vector Machine (SVM)), for the task of mapping sEMG signals to eight upper-limb motions, to find out the relation between these methods and propose a proper combination to solve this issue. Seven subjects participated in the experiment and six muscles of the upper-limb were selected to record sEMG signals. The experimental results showed that NN classifier obtained the highest recognition accuracy rate (88.7%) during the training process while SVM performed better in real-time experiments (85.9%). For time consumption, SVM took less time than NN during the training process but needed more time for real-time computation. Among the four feature extraction methods, WP had the highest recognition rate for the training process (97.7%) while MM performed the best during real-time tests (94.3%). The combination of MM and NN is recommended for strict real-time applications while a combination of MM and SVM will be more suitable when time consumption is not a key requirement.

Design of a novel telerehabilitation system with a force-sensing mechanism.

Many stroke patients are expected to rehabilitate at home, which limits their access to proper rehabilitation equipment, treatment, or assessment by therapists. We have developed a novel telerehabilitation system that incorporates a human-upper-limb-like device and an exoskeleton device. The system is designed to provide the feeling of real therapist-patient contact via telerehabilitation. We applied the principle of a series elastic actuator to both the master and slave devices. On the master side, the therapist can operate the device in a rehabilitation center. When performing passive training, the master device can detect the therapist's motion while controlling the deflection of elastic elements to near-zero, and the patient can receive the motion via the exoskeleton device. When performing active training, the design of the force-sensing mechanism in the master device can detect the assisting force added by the therapist. The force-sensing mechanism also allows force detection with an angle sensor. Patients' safety is guaranteed by monitoring the motor's current from the exoskeleton device. To compensate for any possible time delay or data loss, a torque-limiter mechanism was also designed in the exoskeleton device for patients' safety. Finally, we successfully performed a system performance test for passive training with transmission control protocol/internet protocol communication.

H2S Alleviates Propofol-Induced Impaired Learning and Memory by Promoting Nuclear Translocation of Nrf2 and Inhibiting Apoptosis and Pyroptosis in Hippocampal Neurons.

BACKGROUND: Repeated exposure to propofol can affect their learning and memory functions, but the mechanism remains unclear. The current study aimed to investigate the mechanism underlying the effect of hydrogen sulfide (H2S) on the alleviation of propofol-induced learning and memory impairment, mediated by promoting nuclear translocation of the nuclear factor erythroid 2-related factor 2 (Nrf2) and inhibiting apoptosis and pyroptosis in hippocampal neurons. METHODS: Rats used in this study were successively exposed to 200 mg/kg propofol for 8 consecutive weeks, followed by inhalation of 10, 40 or 80 ppm H2S. Subsequently, the effects of different concentrations of H2S on learning and memory were assessed using the water maze assay. Additionally, the effects of H2S on cell apoptosis and pyroptosis and nuclear translocation of Nrf2 in hippocampal neurons were also determined. Furthermore, NaHS (200 µmol/L) was used as an in vitro donor for H2S, and rescue experiments were carried out following Nrf2 knockdown in H19-7 cells. Moreover, Nrf2 function was inhibited following treatment with an intraperitoneal injection of ML385 (30 mg/kg) in the rats. The effects of H2S on reactive oxygen species (ROS) generation, cell apoptosis, and pyroptosis in propofol-treated and Nrf2-deficient H19-7 cells were also investigated. RESULTS: Exposure to propofol for 8 weeks affected the ability of the rats to find underwater platforms (p < 0.01). Further, the exposure induced cell apoptosis and NLR family pyrin domain containing 3 (NLRP3)-related pyroptosis (p < 0.01). Although inhalation of 10 ppm H2S did not attenuate the aforementioned effects (p > 0.05), exposure to 40 and 80 ppm H2S significantly alleviated propofol-induced injury in the hippocampal neurons (p < 0.01). However, the protective effect of 80 ppm H2S was more obvious as compared to that of the other two doses (p < 0.01). In addition, Nrf2 knockdown aggravated the propofol-induced cell pyroptosis and apoptosis as well as reversed the protective effect of H2S against these processes (p < 0.01). In vivo experiments in this study demonstrated that Nrf2 inhibition abrogated the protective effects of H2S inhalation against learning and memory impairment as well as propofol-induced cell apoptosis and pyroptosis in rats (p < 0.01). CONCLUSIONS: H2S could attenuate propofol-induced damage in hippocampal neurons by promoting the nuclear translocation of Nrf2 and inhibiting cell apoptosis and pyroptosis.

Implementation of human-machine synchronization control for active rehabilitation using an inertia sensor.

According to neuro-rehabilitation practice, active training is effective for mild stroke patients, which means these patients are able to recovery effective when they perform the training to overcome certain resistance by themselves. Therefore, for rehabilitation devices without backdrivability, implementation of human-machine synchronization is important and a precondition to perform active training. In this paper, a method to implement this precondition is proposed and applied in a user's performance of elbow flexions and extensions when he wore an upper limb exoskeleton rehabilitation device (ULERD), which is portable, wearable and non-backdrivable. In this method, an inertia sensor is adapted to detect the motion of the user's forearm. In order to get a smooth value of the velocity of the user's forearm, an adaptive weighted average filtering is applied. On the other hand, to obtain accurate tracking performance, a double close-loop control is proposed to realize real-time and stable tracking. Experiments have been conducted to prove that these methods are effective and feasible for active rehabilitation.

A novel soft biomimetic microrobot with two motion attitudes.

 A variety of microrobots have commonly been used in the fields of biomedical engineering and underwater operations during the last few years. Thanks to their compact structure, low driving power, and simple control systems, microrobots can complete a variety of underwater tasks, even in limited spaces. To accomplish our objectives, we previously designed several bio-inspired underwater microrobots with compact structure, flexibility, and multi-functionality, using ionic polymer metal composite (IPMC) actuators. To implement high-position precision for IPMC legs, in the present research, we proposed an electromechanical model of an IPMC actuator and analysed the deformation and actuating force of an equivalent IPMC cantilever beam, which could be used to design biomimetic legs, fingers, or fins for an underwater microrobot. We then evaluated the tip displacement of an IPMC actuator experimentally. The experimental deflections fit the theoretical values very well when the driving frequency was larger than 1 Hz. To realise the necessary multi-functionality for adapting to complex underwater environments, we introduced a walking biomimetic microrobot with two kinds of motion attitudes: a lying state and a standing state. The microrobot uses eleven IPMC actuators to move and two shape memory alloy (SMA) actuators to change its motion attitude. In the lying state, the microrobot implements stick-insect-inspired walking/rotating motion, fish-like swimming motion, horizontal grasping motion, and floating motion. In the standing state, it implements inchworm-inspired crawling motion in two horizontal directions and grasping motion in the vertical direction. We constructed a prototype of this biomimetic microrobot and evaluated its walking, rotating, and floating speeds experimentally. The experimental results indicated that the robot could attain a maximum walking speed of 3.6 mm/s, a maximum rotational speed of 9°/s, and a maximum floating speed of 7.14 mm/s. Obstacle-avoidance and swimming experiments were also carried out to demonstrate its multi-functionality.

[Experimental study of angiography using vascular interventional robot-2(VIR-2)].

OBJECTIVE: To verify the feasibility and safety of new vascular interventional robot system used in vascular interventional procedures. METHODS: Vascular interventional robot type-2 (VIR-2) included master-slave parts of body propulsion system, image navigation systems and force feedback system, the catheter movement could achieve under automatic control and navigation, force feedback was integrated real-time, followed by in vitro pre-test in vascular model and cerebral angiography in dog. Surgeon controlled vascular interventional robot remotely, the catheter was inserted into the intended target, the catheter positioning error and the operation time would be evaluated. RESULTS: In vitro pre-test and animal experiment went well; the catheter can enter any branch of vascular. Catheter positioning error was less than 1 mm. The angiography operation in animal was carried out smoothly without complication; the success rate of the operation was 100% and the entire experiment took 26 and 30 minutes, efficiency was slightly improved compared with the VIR-1, and the time what staff exposed to the DSA machine was 0 minute. The resistance of force sensor can be displayed to the operator to provide a security guarantee for the operation. No surgical complications. CONCLUSIONS: VIR-2 is safe and feasible, and can achieve the catheter remote operation and angiography; the master-slave system meets the characteristics of traditional procedure. The three-dimensional image can guide the operation more smoothly; force feedback device provides remote real-time haptic information to provide security for the operation.

miR-146b level and variants is associated with endometriosis related macrophages phenotype and plays a pivotal role in the endometriotic pain symptom.

OBJECTIVE: The aim of this study was to explore the effect of miR-146b expression and variants on endometriosis and its associated pain symptom. MATERIALS AND METHODS: Genotyping and expression of miR-146b was performed on 74 endometriosis patients and 23 healthy controls. ESCs were subsequently co-cultured with peripheral blood (PB)-derived monocytes (PBMC)-driven macrophages. After overexpression and inhibition of miR-146b, cytokine production from the macrophages were determined by enzyme-linked immunosorbent assay (ELISA). Western blot were done to measure the regulation of IRF5 by miR-146b. RESULTS: We found that miR-146b expression was increased in PF supernatant and PF CD14 + monocytes/Macrophages of endometriosis patients, with endometriosis patients with pain (EPWP) showing higher miR-146b expression compared with the endometriosis patients without pain (EPNP). CT/CC genotype of miR-146b rs1536309 was associated with the risk of pain symptom of endometriosis. For the function studies, we found that miR-146b was involved in the negative regulation of inflammation through attenuating IRF5 expression. Macrophages from patients who carries CT/CC genotype of miR-146b rs1536309 showed decreasing miR-146b expression and enhancement of the ability of pro-inflammation. CONCLUSIONS: Our findings suggest an important role of miR-146b level and variants in endometriosis that helps to regulate the process of endometriosis and its associated pain.

A tensor-mass method-based vascular model and its performance evaluation for interventional surgery virtual reality simulator.

BACKGROUND: Physics-based vascular modelling is an essential issue to be addressed in the development of the endovascular interventional surgery training system, which helps to shorten the training period of novice surgeons to obtain dexterous skills of surgical operation. METHODS: A blood vessel model based on tensor-mass method (TMM) is formulated and implemented in this context. A multimodel representation is adopted for the vascular model, including the mechanical, visual, and collision model. Triangular and tetrahedral TMM are formulated and implemented in Simulation Open-source Framework Architecture (SOFA). An extensional formulation and analysis of two typical methods are implemented in SOFA. Meanwhile, a set of experiments were conducted to test the refresh rate, the stability, and the visual realism of the vascular deformation simulation, integrating with TMM, mass-spring model, and finite element method. RESULTS: The experimental and subjects' testing results prove that TMM outperforms the current physically based methods in realistic and real-time vascular deformation simulation, which provides a refresh rate up to 256 frame per second on a triangular vascular topology. CONCLUSIONS: The vascular model presented herein provides a fundamental module meeting the real-time and realistic requirements of our endovascular interventional surgery simulator.

Real-Time Evaluation of the Signal Processing of sEMG Used in Limb Exoskeleton Rehabilitation System.

As an important branch of medical robotics, a rehabilitation training robot for the hemiplegic upper limbs is a research hotspot of rehabilitation training. Based on the motion relearning program, rehabilitation technology, human anatomy, mechanics, computer science, robotics, and other fields of technology are covered. Based on an sEMG real-time training system for rehabilitation, the exoskeleton robot still has some problems that need to be solved in this field. Most of the existing rehabilitation exoskeleton robotic systems are heavy, and it is difficult to ensure the accuracy and real-time performance of sEMG signals. In this paper, we design a real-time training system for the upper limb exoskeleton robot based on the EMG signal. It has four main characteristics: light weight, portability, high precision, and low delay. This work includes the structure of the rehabilitation robotic system and the method of signal processing of the sEMG. An experiment on the accuracy and time delay of the sEMG signal processing has been done. In the experimental results, the recognition accuracy of the sEMG is 94%, and the average delay time is 300 ms, which meets the accuracy and real-time requirements.

Application of remifentanil for conscious sedation and analgesia in short-term ERCP and EST surgery.

This study aims to observe and evaluate the use of remifentanil in conscious sedation and analgesia for the safety and comfort of patients undergoing short-term endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincterotomy (EST).Sixty-eight patients who underwent ERCP and EST were randomly divided into two groups: research group and control group. Patients in the research group were intravenously injected with remifentanil (80-2/3* age) for 1 to 2 minutes, combined with the intravenous injection of propofol (20-30 mg) during the course of treatment. ERCP surgery was performed when Ramsay sedation scale (RSS) score reached 2-3. During the surgery, patients were closely monitored for cough symptoms, aspiration, and respiratory and circulatory system performance, and timely treatment was performed. Sedative drugs were not given in patients in the control group.In research group, the circulatory and respiratory depression of patients was mild, only one patient needed to be treated, and there was no arrhythmia requiring treatment. Five patients had respiratory depression (blood oxygen saturation decreased to <90%), which was immediately corrected. There were no interruptions during surgery due to body movement, cough, or aspiration.The use of remifentanil for conscious sedation and analgesia can be broadly applied in short-term ERCP, which greatly improves patient comfort during the surgery. This approach may bear promise for a widespread use in future clinical practice.

Effect of subarachnoid nerve block anesthesia on glutamate transporter GLAST and GLT-1 expressions in rabbits.

OBJECTIVE: To observe the effect of subarachnoid nerve block anesthesia on glutamate transporter glutamate-aspartate transporter (GLAST) and GLT-1 expressions in rabbits, and to investigate the effect of peripheral nerve anesthesia on the morphology and function of the spinal cord. METHODS: Twenty healthy New Zealand white rabbits were randomly divided into two groups: the experimental group and control group; with 10 rabbits in each group. For spinal nerve anesthesia, 5 g/L of bupivacaine was used in the experimental group, and sterile saline was used in the control group. After 30 min of cardiac perfusion, GLAST and GLT-1 protein expression in spinal neurons were detected by immunohistochemistry and immunofluorescence staining. RESULTS: GLAST and GLT-1 protein-positive cells increased in neurons in the experimental group, compared with the control group (P < 0.05). CONCLUSIONS: After subarachnoid nerve block anesthesia, rabbit glutamate transporter GLAST and GLT-1 expression is increased; and spinal cord nerve cell function is inhibited.