1.Recognition of walking stance phase and swing phase based on moving window.
Xiaobo GENG ; Peng YANG ; Xinran WANG ; Yanli GENG ; Yu HAN
Journal of Biomedical Engineering 2014;31(2):273-278
Wearing transfemoral prosthesis is the only way to complete daily physical activity for amputees. Motion pattern recognition is important for the control of prosthesis, especially in the recognizing swing phase and stance phase. In this paper, it is reported that surface electromyography (sEMG) signal is used in swing and stance phase recognition. sEMG signal of related muscles was sampled by Infiniti of a Canadian company. The sEMG signal was then filtered by weighted filtering window and analyzed by height permitted window. The starting time of stance phase and swing phase is determined through analyzing special muscles. The sEMG signal of rectus femoris was used in stance phase recognition and sEMG signal of tibialis anterior is used in swing phase recognition. In a certain tolerating range, the double windows theory, including weighted filtering window and height permitted window, can reach a high accuracy rate. Through experiments, the real walking consciousness of the people was reflected by sEMG signal of related muscles. Using related muscles to recognize swing and stance phase is reachable. The theory used in this paper is useful for analyzing sEMG signal and actual prosthesis control.
Artificial Limbs
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Electromyography
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Humans
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Leg
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Muscle, Skeletal
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physiology
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Walking
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physiology
2.Effects of physiological testosterone on transcription factor activity in human umbilical vein endothelial cells.
Hong JIN ; Wen-Bing QIU ; Geng PENG
Chinese Journal of Applied Physiology 2008;24(3):347-376
Cells, Cultured
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Flutamide
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pharmacology
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Human Umbilical Vein Endothelial Cells
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cytology
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drug effects
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metabolism
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Humans
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Proto-Oncogene Proteins c-myb
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metabolism
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Sp1 Transcription Factor
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metabolism
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Testosterone
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antagonists & inhibitors
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physiology
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Transcription Factors
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metabolism
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Tumor Suppressor Protein p53
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metabolism
3.The express of angiotensin Ⅱ in lungs during bilateral femoral arteriovenous shunt for extracorporeal membrane oxygenation
Peng XIA ; Xigang GENG ; Yang YAN
Chinese Journal of Thoracic and Cardiovascular Surgery 2008;24(2):119-121
Objective To study the change of angiotensin Ⅱ in the applications of pumpless ECMO, and its effect on prognosis of the acute respiratory failure. Methods The study was performed in ten dogs [ weight 18 - 35 kg, mean weight ( 23.4 ± 4.7 ) kg].A respiratory failure animal model was established end then was treated by bilateral femoral artery-venous ECMO. Collection right atriurn blood end constitution of lung at different time (before ECMO, during ECMO 1h, 2h, 3h, 4h). Angiotensin Ⅱ content in blood and lung homogenate was detected by radio-immunity mothod. Angiotensin Ⅱ expression loci in lung were detected by immunohistochemistry mothod. Results Angiotensin Ⅱ content in plasma was decreased at completion of the model, it was back up at 1 hour and reached the peak at 3 hours, then it slowly declined. Angiotensin Ⅱ content in lung homogenate increased at the beginning, peaked by 2 hours, end then it decreased. Loci angiotensin Ⅱ in lung by immunohistochemistry were expressed in most of epithelial cells cytoplast of bronchiole dissepimont, smooth muscle cell cytoplast of small blood vessel around it end a few macrophage cytoplasts during the model time..Conclusion It is valuable to measure engiotensin Ⅱ in blood through the bilateral femoral artery-venous ECMO, because it can reflect angiotensin Ⅱ in lung and the resume of lung in certain degree.
4.Regulation of miR-1 and miR-133 a on L-type calcium channel Cavβ2 and α1C subunits in rat cardiomyocyte hypertrophy
Yuqin WANG ; Peng GENG ; Yang WU
Basic & Clinical Medicine 2015;(2):196-202
Objective To investigate the regulation of miR-1 and miR-133 a on L-type calcium channel β2 subunit ( Cavβ2 ) and α1C subunit during rat cardiomyocyte hypertrophy .Methods Cardiomyocyte hypertrophy was in-duced by isoproterenol (ISO, 10μmol/L).The targets of miR-1 and miR-133a were predicted by online database microCosm and Targetscan , respectively .The 3′untranslated region sequences of Cavβ2 andα1C were respectively cloned into reporter vector and then transiently transfected into HEK 293 cells.The luciferase activities of samples were measured for demonstrating the expression of luciferase reporter vector .The protein expression of Cavβ2 andα1C were evaluated by Western blot .The expression levels of Cavβ2 andα1C were inhibited by RNAi to determine theeffectsofCavβ2andα1Concardiomyocytehypertrophy.Results 1)Cavβ2wasoneofpotentialtargetsof miR-1,α1C was the one of potential targets of miR-133a.2) The luciferase activities of HEK293 cells with the plasmid containing widetype Cavβ2 3′UTR sequence or α1 C significantly decreased ( P <0.05 , P <0.01 ) . 3 ) Upregulation of the miR-1 and miR-133 a by miR-1 mimic and miR-133 a mimic transfection suppressed pro-tein expression of Cavβ2 and α1C, respectively(P<0.01, P<0.05).4)Downregulation of Cavβ2 andα1C by RNAi could markedly inhibit the increase of cell surface area ( P<0.01 ) , mRNA expression of ANP andβ-MHC (P<0.05).Conclusions Cavβ2 is the target gene of miR-1 and α1C is the target gene of miR-133a.miR-1 and miR-133a can negatively regulate the expression of L-type calcium channel Cavβ2 andα1C subunit, inhibi-ting cardiomyocyte hypertrophy.
5.Hydrodynamic Chromatography and Slalom Chromatography and Their Applications
Jianjun LI ; Peng LIU ; Xindu GENG
Chinese Journal of Analytical Chemistry 2009;37(7):1082-1087
Hydrodynamic chromatography(HDC) and slalom chromatography(SC) called as dynamic liquid chromatography(DLC) were introduced and reviewed, mainly for the recent development of separation principle, theoretical model, and applications. Fifty two
6.Volar locking compression plate fixation for dorsally displaced fractures of distal radius
Peifu TANG ; Peng HUANG ; Geng CUI
Orthopedic Journal of China 2006;0(16):-
[Objective]To evaluate a preliminary outcome of volar surgical treatment of dorsally displaced fractures of distal radius with open reduction and internal fixation with T shape locking compression plate(TLCP).[Method]From Sept.2003 to Nov.2005,9 cases with dorsally unstable distal radius fractures were treated with open reduction and internal fixation with T-LCP.This study involved 3 males and 6 femals with an average age of 63.5 years(ranged from 52 to 74 years old).According to AO classification: 2 cases of types B2;1 case of type B3;2 cases of type C1;3 cases of type C2;1 case of type C3,all of them were closed fractures of distal radius.The fractures of 9 cases were fixated with T-LCP by volar approach and dorsal soft tissues were not dissected during the operation.The Osteosets and the artificial bone substitute were implanted into bone defects if they were large enough.[Result]Nine cases were followed up for 6 to 17 months and the average time was 10.7 months.The X-ray pictures showed that unions have been achieved in all patients and a mean healing time was 7 weeks.The Osteosets were implanted into large bone defects in one case.No complication was found as infection,non-union,loosing of nails,syndrome of wrist,and medium neuritis.The functional recovery was achieved from 6 to 29 weeks with an average time of 12.5 weeks after operation.Passive wrist motion,active finger motion and forearm rotation were encouraged immediately after surgery.Active wrist motion was suggested in 7 days postoperatively.The clinical outcomes were evaluated according to modified Mcbide grading system.There were 7 excellent,1 good and 1 fair,the satisfactory rate was 88.9%.[Conclusion]The volar fixation of T-LCP for dorsally displaced fractures of distal radius has a good clinical outcome.It allows the patients to begin early exercise.
7.THE CHANGES OF MYOCARDIAL ULTRASTRUCTURE AND CELL MEMBRANE CHANNEL IN UREMIC RATS
Jianzhong MENG ; Kanfu PENG ; Min GENG
Medical Journal of Chinese People's Liberation Army 2001;0(11):-
The aim of this study was to explore the myocardial ultrastructure of experimental uremic rats and the effect of myocardiocyte succinate dehydrogenase(SDH) and free cytosolic calcium changes on membrane channel. By making a uremia model in rats, changes of SDH activation was observed by quantitative enzyme cytochemistry methods and membrane calcium channel was checked by laser scanning confocal microscopy. The results showed that with the uremia becoming heavier, myocardiocyte membrane was rolled and broken, myofibrils were swollen and broken. The quantity of mitochondria with SDH products significantly decreased, while activation of cell membrane calcium channel markedly increased and cytosolic calcium piled up. It is suggested that impaired myocardial membrane, decreased contents of mitochondrial function enzyme and cytosolic calcium overload are the pathophisiological basis leading to cardiac dysfunction in uremia.
9.Repetitive transcranial magnetic stimulation for the rehabilitation of vascular dementia: Mechanisms
Fei WANG ; Xin GENG ; Huaying TAO ; Peng ZHAO ; Yan CHENG
Chinese Journal of Physical Medicine and Rehabilitation 2010;32(10):730-734
Objectiye To study the mechanism by which transcranial magnetic stimulation (rTMS) affects cognitive dysfunction in vascular dementia (VD). Methods Thirty-six male Wistar rats were randomly divided into a control group, a VD group, a low frequency rTMS group and a high frequency rTMS group. Two-vessel occlusion was employed to induce VD models. Low frequency rTMS group rats were given 0.5 Hz rTMS for six weeks. High frequency rTMS group rats were given 5 Hz rTMS for six weeks. Morris' water maze test was used to measure their spatial learning ability and memory. The ultrastructures of the synapses in the four groups were detected with transmission electron microscopy. The expression of synaptophysin (SYN), brain derived neurotrophic factor (BDNF) and Nmethyl-D-aspartate receptor 1 ( NMDAR1 ) mRNA and protein in the hippocampus were determined by real-time PCR and Western blotting. Results The behavior and morphology of the rats treated with rTMS improved. The average expression of SYN, BDNF and NMDAR1 mRNA and protein in the low frequency rTMS group and the high frequency rTMS group were significantly higher than in the VD group. Conclusion rTMS can provide a rehabilitative effect for VD. The mechanism might be associated with enhancing the expression of SYN, BDNF and NMDAR1 in the hippocampus.