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Objective To investigate the effects of ultrashort wave treatment on joint dysfunction and muscle atrophy in a rabbit model of extending knee joint contracture. Methods Forty rabbits were randomly divided into eight groups. In group C, the left knee joint was not fixed. In group I-8, the left knee joint was only fixed for eight weeks. In groups R-1, R-2, and R-4, the left knee joint was fixed for eight weeks before the rabbits underwent one, two, and four weeks of self-recovery, respectively. In groups T-1, T-2, and T-4, the left knee joint was fixed for eight weeks before the rabbits underwent one, two, and four weeks of ultrashort wave treatment, respectively. The degree of total contracture and myogenic contracture were measured, the cross-sectional area (CSA) and protein levels for myogenic differentiation (MyoD) of the rectus femoris were evaluated. Results There was a tendency toward a reduced degree of total and myogenic contracture, and also a tendency toward an increased CSA of the rectus femoris and increased protein levels for MyoD after both self-recovery and ultrashort wave treatment. The ultrashort wave was more effective than self-recovery in reducing the total and myogenic contracture, and increasing the CSA and MyoD protein levels of the rectus femoris. Conclusions Ultrashort wave treatment may ameliorate joint dysfunction and muscle atrophy by upregulating the expression of MyoD protein in a rabbit model of extending knee joint contracture.

Background: The aim of this study was to investigate the therapeutic effect of electrical stimulation on disuse muscular atrophy in a rabbit model of knee joint contracture and explore the role of endoplasmic reticulum stress-induced Parkin-dependent mitophagy in this process.Methods: Two sub-experiments were carried out successively in our study. In the first sub-experiment, 24 rabbits were divided into four groups on average based on the immobilization time: Ctrl 1, I-2, I-4, and I-6 groups. In the second sub-experiment, 24 rabbits were also divided into four groups on average in accordance with the process mode: Ctrl2, ES, NR, and EST groups. To test the time-dependent changes of the rectus femoris muscles after immobilization in rabbits, and to evaluate the effect of electrical stimulation on the atrophic rectus femoris muscles, the wet weights of rectus femoris muscles were assessed in this study, along with the protein levels of atrogin-1, p-PERK, Parkin and COXIV.Results: The wet weights of rectus femoris muscles, the protein levels of atrogin-1, p-PERK and Parkin increased after immobilization. It was also revealed that the protein levels of COXIV decreased after immobilization. Electrical stimulation was effective against muscle atrophy, the elevated expression of atrogin-1, p-PERK, Parkin, and the decreased expression of COXIV.Conclusions: Immobilization of unilateral lower limb could induce rectus femoris muscle atrophy, endoplasmic reticulum stress and Parkin mediated mitophagy. Endoplasmic reticulum stress-induced Parkin-dependent mitophagy may be one of the mechanisms by which electrical stimulation can play a significant role.

Objective: The present study was to investigate the effect of low-frequency electrical stimulation on disuse muscle atrophy and its mechanism in a rabbit model of extending knee joint contracture.Methods: This study designed two experiments. In the time-point experiment, 24 rabbits were randomly divided into Control 1(Ctrl1), immobilization for 2 weeks (I-2), I-4, and I-6 groups. In the intervention experiment, 24 rabbits were also randomly divided into Control 2 (Ctrl2), electrical stimulation (ES), natural recovery (NR) and electrical stimulation treatment (EST) groups. All intervention effects were assessed by evaluating the knee joint range of motion (ROM), cross-sectional area (CSA) of muscle and the expression of autophagy-related proteins.Results: Time-point experiment showed that immobilization reduced knee ROM, muscle CSA, and activated autophagy in skeletal muscle. Levels of four autophagic proteins including p-mTOR, Atg7, p62 and LC3B-II, were significantly elevated in the skeletal muscle of I-4 group. The intervention experiment further presented that LFES significantly improved the immobilization-induced ROM and CSA reduction. Additionally, LFES significantly reversed autophagy activation of skeletal muscle caused by immobilization.Conclusions: Low-frequency electrical stimulation alleviates immobilization-evoked disuse muscle atrophy maybe via inhibiting autophagy in skeletal muscle of rabbits.

Background The study aimed to investigate the effect of low-frequency electrical stimulation (LFES) on disuse muscle atrophy and its mechanism in a rabbit model of knee extension contracture. Methods This study involved two experiments. In the time-point experiment, 24 rabbits were randomly divided into 4 groups: Control 1 (Ctrl1 group), immobilization for 2 weeks (I-2 group), immobilization for 4 weeks (I-4 group), and immobilization for 6 weeks (I-6 group). In the intervention experiment, 24 rabbits were randomly divided into 4 groups: Control 2 (Ctrl2 group), electrical stimulation (ESG group), natural recovery (NRG group), and electrical stimulation treatment (ESTG group). All intervention effects were assessed by evaluating the knee joint range of motion (ROM), cross-sectional area (CSA) of the rectus femoris muscle, and expression of autophagy-related proteins. Results The time-point experiment showed that immobilization reduced the knee ROM, reduced the rectus femoris muscle CSA, and activated autophagy in skeletal muscle. The levels of five autophagy-related proteins [mammalian target of rapamycin (mTOR), phosphorylated mTOR (p-mTOR), autophagy-related protein 7 (Atg7), p62, and microtubule-associated protein light chain 3B-II (LC3B-II)] were significantly elevated in the skeletal muscle of the I-4 group. The intervention experiment further showed that LFES significantly improved the immobilization-induced reductions in ROM and CSA. Additionally, LFES resulted in a significant decrease in the protein expression of mTOR, p-mTOR, Atg7, p62, and LC3B-II in the rectus femoris muscle. Conclusions LFES alleviates immobilization-evoked disuse muscle atrophy possibly by inhibiting autophagy in the skeletal muscle of rabbits.

The clinical treatment of joint contracture due to immobilization remains difficult. The pathological changes of muscle tissue caused by immobilization-induced joint contracture include disuse skeletal muscle atrophy and skeletal muscle tissue fibrosis. The proteolytic pathways involved in disuse muscle atrophy include the ubiquitin-proteasome-dependent pathway, caspase system pathway, matrix metalloproteinase pathway, Ca2+-dependent pathway and autophagy-lysosomal pathway. The important biological processes involved in skeletal muscle fibrosis include intermuscular connective tissue thickening caused by transforming growth factor-β1 and an anaerobic environment within the skeletal muscle leading to the induction of hypoxia-inducible factor-1α. This article reviews the progress made in understanding the pathological processes involved in immobilization-induced muscle contracture and the currently available treatments. Understanding the mechanisms involved in immobilization-induced contracture of muscle tissue should facilitate the development of more effective treatment measures for the different mechanisms in the future. Keywords: Immobilization-induced joint contracture, Disuse skeletal muscle atrophy, Skeletal muscle fibrosis, Treatment

Purpose: We investigate the underlying biological effects and mechanisms of rESWT on myogenic contracture and muscle atrophy in a rabbit model of extending knee joint contracture.Materials and Methods: In group control, the knee joint was not fixed. In group I-4w, the knee joint was only fixed for 4 weeks. In groups SR-1 w, SR-2 w, and SR-4 w, the knee joint was fixed for 4 weeks before the rabbits underwent 1, 2, and 4 weeks of self-recovery, respectively. In groups rESWT-1 w, rESWT 2 w, and rESWT-4 w, the knee joint was fixed for 4 weeks before the rabbits underwent 1, 2, and 4 weeks of rESWT, respectively. The myogenic contracture was measured, the cross-sectional area and key protein levels for NF-κB/HIF-1α signaling pathway and myogenic regulatory factors were evaluated.Results: During the recovery period, biological findings showed that the levels of myogenic contracture and muscle atrophy were milder in group rESWT by compared with group SR after 2 weeks. Molecular biological analysis showed that MyoD protein levels in the group rESWT was significantly higher than those in the group SR, and importantly, phospho-NF-κB p65 and HIF-1α protein levels in the group rESWT were significantly lower than those in the group SR at the same time point.Conclusions: This is the first study demonstrated that rESWT has the potential to reduce myogenic contracture and muscle atrophy after long-term immobilization in animal model. It is a possible mechanism that changing the low oxygen environment in skeletal muscle through rESWT may inhibit activation of NF-κB/HIF-1α signaling pathway.

BackgroundRecent studies have shown that radial extracorporeal shock wave therapy (rESWT) modulates viability and gene expression of human skeletal muscle cells in vitro. However, the underlying biological effects and mechanisms of rESWT on muscle atrophy and myogenic contracture in animal mode have not yet been investigated.ObjectiveTo investigate the underlying biological effects and mechanisms of rESWT on myogenic contracture and muscle atrophy in a rabbit model of extending knee joint contracture.MethodsForty rabbits were randomly divided into eight groups. In group Control, the left knee joint was not fixed. In group I-4w, the left knee joint was only fixed for four weeks. In groups SR-1w, SR-2w, and SR-4w, the left knee joint was fixed for four weeks before the rabbits underwent one, two, and four weeks of self-recovery, respectively. In groups rESWT-1w, rESWT-2w, and rESWT-4w, the left knee joint was fixed for four weeks before the rabbits underwent one, two, and four weeks of rESWT, respectively. The degree of myogenic contracture was measured, the cross-sectional area and key protein levels for NF-κB/HIF-1α signaling pathway and myogenic regulatory factors of the rectus femoris were evaluated.ResultsDuring the recovery period, biological findings in this study showed that the levels of myogenic contracture and muscle atrophy were milder in group rESWT by compared with group SR at the same time point. Molecular biological analysis in the present study showed that MyoD protein levels in the group rESWT was significantly higher than those in the group SR, and importantly, phospho-NF-κB p65 and HIF-1α protein levels in the group rESWT were significantly lower than those in the group SR at the same time point.ConclusionsOur study demonstrates that rESWT has the potential to reduce myogenic contracture and muscle atrophy after long-term immobilization in animal model. It is a possible mechanism that changing the low oxygen environment in skeletal muscle through rESWT may inhibit activation of NF-κB/HIF-1α signaling pathway, thereby enhancing the expression of myogenic regulatory factors.

OBJECTIVE The purpose of this study was to examine the intervention effect of radial extracorporeal shock wave combined with ultrashort wave diathermy on immobilization-induced fibrosis and contracture of muscle. DESIGN The groups included male rabbits for the group (control group). To cause joint contracture, rabbits underwent plaster fixation of a left knee joint at full extension. After immobilization for 4 wks, all rabbits were randomly divided into five groups: model group, natural recovery group, radial extracorporeal shock wave treatment group, ultrashort wave diathermy group, and radial extracorporeal shock wave combined with ultrashort wave diathermy group. All intervention effects were assessed by evaluating the cross-sectional area and the collagen deposition of muscle, the knee joint range of motion and the protein levels for transforming growth factor β1 and hypoxia-inducible factor 1α. RESULTS The combined treatment group got the best recovery of the knee joint function. The combined treatment was more effective than radial extracorporeal shock wave or ultrashort wave diathermy alone against the fibrosis and contracture of muscle, as well as the overexpression of transforming growth factor β1 and hypoxia-inducible factor 1α. CONCLUSIONS Radial extracorporeal shock wave combined with ultrashort wave diathermy was effective in alleviating immobilization-induced contracture and fibrosis of muscle, as well as reducing the molecular manifestations of muscle fibrosis.

Acute inflammation is an anti-injury stress response which is beneficial to the human body. However, if the duration of acute inflammation is prolonged in specific people, such as critically ill patients and people with low resistance, it will worsen the disease and increase complication rates. Most medical researchers are committed to finding an effective method to shorten the duration of acute inflammation. The purpose of our work is to shorten the duration of acute inflammation in a rabbit’s ear wound by dielectric barrier discharge (DBD) low temperature plasma. The distribution and quantity of inflammatory cells in the rabbit’s ear wound treated by plasma were studied and calculated by using a high power optical microscope and Image J software. The reactive species of plasma were characterized by optical emission spectroscopy. The results showed that the number of inflammatory cells decreased from 2312.17 ± 242.52 to 880.17 ± 89.08 after plasma treatment for 3 min. In addition, plasma has a coagulation effect on the rabbit’s ear wound. Our results indicated that DBD low temperature plasma could be an effective tool to decrease the inflammatory response time and the inflammation was further alleviated with increased treatment time.Acute inflammation is an anti-injury stress response which is beneficial to the human body. However, if the duration of acute inflammation is prolonged in specific people, such as critically ill patients and people with low resistance, it will worsen the disease and increase complication rates. Most medical researchers are committed to finding an effective method to shorten the duration of acute inflammation. The purpose of our work is to shorten the duration of acute inflammation in a rabbit’s ear wound by dielectric barrier discharge (DBD) low temperature plasma. The distribution and quantity of inflammatory cells in the rabbit’s ear wound treated by plasma were studied and calculated by using a high power optical microscope and Image J software. The reactive species of plasma were characterized by optical emission spectroscopy. The results showed that the number of inflammatory cells decreased from 2312.17 ± 242.52 to 880.17 ± 89.08 after plasma treatment for 3 min. In addition, plasma has a coagulatio...

By application of the theory and methods of discrete element, a loader loading process three-dimensional simulation model was established, the simulation model established in EDEM software realized the visualization of loader inserting process. By three different particle size materials inserting process simulation, material motion characteristic could be obtained and the laws of motion of different size material were compared. Simulation results show that regardless of the particle size, compaction zone (dense core) were generated. For small particles, during insertion of the material there was a distinct shear slip plane and for coarse particles, slip plane was not obvious. The simulation results were consistent with the results of previous analysis and verified that the discrete element method and the model in the loading process were effective in the study.

Aiming at the design and development of integrated Manufacturing Execution System (MES) of solar photovoltaic modules production, the difficulty of the manufacturing execution management was pointed out combining with solar photovoltaic modules production flow, the goals and main functions of the integrated MES were analyzed and designed based on the analysis of solar photovoltaic modules production enterprise’s main characteristics and management status. The physical data model of MES was designed by Power Designer software and some key function modules which include workshop plans and scheduling management, Workflow management and control system and process quality control were developed based on J2EE. The practical applications in some solar photovoltaic modules production enterprises were proved that the integrated MES could enhance the manufacturing management level of solar photovoltaic modules production effectively.

For the design and development problems about intelligent Manufacturing Execution System of tungsten powder processing, the difficulty in the manufacturing execution management is pointed out combining Tungsten powder process flow. Goal of the system is analyzed and its main function is designed. Collaboration as the core, integrated system architecture is established from three aspects of system function, time and space. The physical data model is designed by using PowerDesigner, the manufacturing execution system is developed based on JSP. Through practical enterprise application, it is proved that the system immensely enhance the manufacturing execution management level for the Tungsten powder processing enterprise.

Considering the practical problems in the threshing and redrying production, in order to improve the manufacturing process quality, by using twice hot-air tobacco embellishing as the critical process in production flow and applying SPC technology, through the online data collection, this paper analyzed the causes of quality defects in the course of production and made adjustments. The conclusion is that SPC technology ensures the quality stability of the tobacco processing progress, and also strongly improves the process capability, which achieves the 3σ Control of product quality.

For the development about Manufacturing Execution System of mould making, the difficulty in manufacturing execution management is pointed out by combining mould making process with current management regulations of mould making enterprises. Goal of the system is analyzed and its main function is designed. System architecture is established based on WEB platform and B/S mode, The physical data model is designed by using PowerDesigner software and implementation methods of some critical functions for manufacturing execution system are developed based on JSP. Through practical enterprise application, it is proved that the system immensely enhance the manufacturing execution management level for mould making enterprises.

According to the work requirements of a production line of sheet metal handling, using the mechanical design principles and methods, pneumatic technology and PLC control technology for sheet metal handling manipulator research and design, and development a style of automatic handling manipulator meeting the requirements. This article introduced the sheet metal handling manipulator and principles of the basic structure of the hand, pneumatic systems and PLC control system design and analysis. Practice shows that the manipulator has a simple structure, reliable, efficient features, which meet actual production needs.