Objective Impedance control plays an important role in stability.This paper intends to explore such mechanism through modeling human reaching movement.Method Implemented with revised model,we ap-ply optimal control theory to neuro-muscle-skeleton model to calculate the stiffness ellipses.Result Com-pared with the original model and experimental figures,the model we proposed could overcome the shortage of monotonous changing of the original one and fit the data better.Conclusions So that this paper concludes that co-contraction contributes to impedance control even during free upper limb planar movement.

BACKGROUND:Stem cell transplantation and tissue engineering in repairing bone defects is a hotspots of recent study.OBJECTIVE:To observe the therapeutic effect of engineering repair on bone defect by auto-transplantation of bone marrow stromal cells(BMSCs)DESIGN: Left-right comparative studySETTING:Experimental center of the First Affiliated Hospital of Harbin Medical UniversityMATERIALS:Twelve New Zealand rabbits with birth age of 10 days to 2months were selected ,male or female with body mass of 2 to 2.5 kg.METHODS :The experiment was conducted in the Experimental Center of First Clinical Medical College, Harbin Medical University from June 2002to June 2003. Self-BMSCs were separated for subculture. 1.5 cm bone was intercepted at middle of radius in 12 rabbits so as to simulate complete bone defect. Then, the left radius defect was filled with collagen sponge carrying BMSCs ( experimental side),which was replaced by simple collagen sponge in the right side(control side). Twelve weeks later, rabbits were put to death and the outcomes of both sides were compared.X-ray assessment was accorded to the standardized stage of bone defect repair (bone repair was graded into 0 to 5 grades,grade 5 implies that bone defect has been completely replaced by new bone,grade 0 implies that no new bone repair).MAIN OUTCOME MEASURES:The general observations of rabbit radius defects,X-ray scanning, histological and electro-microscopic observations.At week 12, callus became strong and protruded to bone defects in experimental side,well connecting with broken ends. While broken ends in control group were only connected by fibrous tissue and no continuous callus was found continuously crossing through the bone defect of experimental side, marrow cavity was smooth, but molding was incomplete. While in control side, no continuous callus could be observed passing through the broteoblasts and new stroms could be observed in bone defect of experimental side, but only a few of osteocytes appeared in the broken ends of control vations: The osteoblast observed in the experimental side seems normal and was rich in enlarged endoplasmic reticula energetic in ,protein synthesis and abundant in organelle.CONCLUSION :As osteogenetic cells, BMSCs possess better osteogenesis property. They can be used as seed cellsin bone defect repair by using bone-engineering techniques.

AIM: To investigate the effect of insulin on vascular smooth muscle cells (VSMCs) proliferation and to evaluate the intracellular signaling pathways involved. METHODS; VSMCs separated from Sprague - Dawley rats were used in this study. The proliferation of VSMCs induced by insulin was assayed by [~3H ] - thymidin incorporation. The protein expression and activity of p -ERK1/2 were determined by immunblot and [~(γ-32)P]ATP incorporation. RESULTS: Insulin induced cell proliferation in a concentration - dependent manner. The proliferative effect of insulin on VSMCs was inhibited partly by LY294002 (48.8% ) , an inhibitor of PI -3 kinase, and the ERK1/2 inhibitor PD98059 (43.6% ) , respectively. Moreover, phosphorylation of ERK1/2 and activity of ERK1/2 induced by insulin were also inhibited partly by LY294002.CONCLUSION: PI -3 kinase and ERK1/2 are involved in insulin induced VSMCs proliferation.

Objective To explore the clinical application of lesser saphenous-sural nerve adipofascial flap accompanied with a full-thickness skin graft taken from the groin area for reconstruction of the distal one third of anterior tibia,.around the ankle. Methods A distally based lesser saphenous.sural nerve adipofag.cial flap accompanied with a full-thickness skin graft which was taken from the groin area was studied and used to treat 12 patients with soft tissue defects in the distal one third of anterior tibia,3 cases with soft tissue defects and tibia osteomyelitis,2 cases with soft tissue defects and tibia osteomyelitis.The size of the soft tissue defects ranged from 3 cm×5 cm to 9 cm×13 cm,and the biggest donor flap was 13 cm×18 cm.The donor sites at the posterior aspect of the leg and at the groin area were closed primarily. Results All 17 patients were followed up for 6-12 months(average 9 months).All 17 flaps had good perfusion and survived completely,which successfully treated all 17 patients with soft tissue defects or with both soft tissue defects and osteomyelitis.The donor and recipient sites of adipofascial flaps and the groin area healed primarily,and satisfactory appearance and function were achieved.Conclusion Distally based lesser saphenous-sural nerve adipofascial flap accompanied with a full-thickness skin graft which was taken from the groin area can reconstruct the distal one third of anterior tibia,around the ankle,and even treat osetomyelitis successfully,in the same time,which can preserve the function and appearance of the involved limb to the utmost.

ObjectiveTo investigate the clinical effects of systems integrative rehabilitation therapy for cervival spdylotsis myelopathy.MethodsFrom April 2002 to October 2004, 68 cases were intervened with the integrative rehabilitation treatment, which linked up the pre- and post-operational rehabilitation interventions into a continuum. The cases were followed up, and serial radiological evaluations were applied. Then the height of involved interspinal space was measured preoperatively and 12 months after operation, and the spinal function was evaluated according to the standard of Japanese Orthopeadic Association (JOA).ResultsAll the cases were followed up, of which 49 were better, 1 was improved, none was worsened. 12 months after operation, roentgenographic appearance showed that the allograft healing and interbody fusion of all patients were achieved, and the reserving height of involved interspinal space and JOA evaluation postoperatively were significantly superior to preoperatively. There was no complications such as cervical spinal cord injury, internal fixation loosening and hematoma turned up.ConclusionThe integration rehabilitation therapy has satisfactory effects in the cervical spondylotsis myelopathy.

AIM: To investigate the changes of intracellular calcium ion (Ca2+) concentration in mouse H9c2 (2-1) cells transfected with or without FK506 binding protein 12.6(FKBP12.6) gene by ultrasound mediated destruction of microbubbles. METHODS: The pcDNA3.1-FKBP12.6 plasmid, mingled with albumin-coated microbubbles agents, was transfected into H9c2 (2-1) cells by ultrasound-mediated destruction of microbubbles. The H9c2 (2-1) cell growth state was investigated by inverted microscope. The changes of intracellular Ca2+ concentration was determined by laser scanning confocal microscope. The FKBP12.6 protein expression was checked by immunohistochemistry. RESULTS: As compared with control cells, the H9c2 (2-1) cells, transfected with FKBP12.6 gene, grew better, had higher gross intracellular Ca2+ concentration. CONCLUSION: FKBP12.6 gene augments Ca2+ concentration in mouse H9c2 (2-1) cells, enhances the contractibility of the myocardial cell, which may be helpful to improve the myocardial dysfunction.

AIM: To identify proteins involved in insulin stimulation and the molecular mechanism of proliferation and migration in vascular smooth muscle cells (VSMCs). METHODS: A series of methods, including 2-D electrophoresis, PDQuest software analysis of 2-DE gels, peptide mass fingerprinting based on matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) and SWISS-PROT database searching, were used to separate and identify the differentially expressed proteins. The difference of some proteins was proved by Western blotting. Proliferation and migration of VSMCs treated with insulin were also observed. RESULTS: DNA synthesis were increased in VSMCs. ~3H-thymidine incorporation in VSMCs from SHR (14.40?0.85) was higher than that in VSMCs from WKY (9.21?0.93, P

Objective To evaluate the effects on blood pressure and vascular endothelial-1 function of combined therapy of atrovastin and nifedipine controlled released tablet in essential hypertension.Methods A randomized,double-blind,controlled trial was performed.Eighty-two patients with essential hypertension were randomly divided into two groups,receiving nifedipine controlled released tablet 30 mg once daily,or atrovastin 10 mg once daily and nifedipine controlled released tablet 30 mg once daily for 12 weeks.Another 30 subjects with normal blood pressure served as normal blood pressure control.Antihypertensive efficiency was observed during the whole study period.The concentration of plasma endothelin-1(ET-1) nitric oxide(NO) were measured before and after treatment.Results Blood pressure decreased significantly in both groups,but more significant in combined therapy group.In the combined therapy group,atrovastin resulted in a significant reduction of plasma ET-1 and a rise of nitric oxide(NO)(P

OBJECTIVE To analyze the pathogen distribution and resistance pattern of the positive clinical sputum specimens in our hospital.METHODS The bacteria and fungi were identified by API system.The susceptibility of antimicrobial and antifungal agents was tested by KB and Rosco disk diffusion method and the data were analyzed by WHONET 5.4 software.RESULTS In 2008,in our hospital,the majority of the positive specimens were distributed among cerebral surgery department,intensive care unit(ICU),respiratory and pediatric departments.The pathogens of the eight highest isolating rate were Pseudomonas aeruginosa(20%),Candida albicans(18%),Acinetobacter baumannii(10.7%),Staphylococcus aureus(6.5%),Klebsiella pneumoniae(6%),Enterobacter cloacae(4%),Haemophilus influenzae(3.8%),and Stenotropho maltophilia(3.5%).In view of the resistance,no Staphylococcus species were resistant to vancomycin,but they were resistant to many other antimicrobial agents.Gram-negative Enterobactericaeae were sensitive to carbapenems,cefoperazone/sulbactam and piperacillin/tazobactam.Among nonfermenters,P.aeruginosa and S.maltophilia were resistant to the most antimicrobial agents while Acinetobacter were comparatively sensitive to carbapenems and cefoperazone/sulbactam.CONCLUSIONS The pathogens in lower respiratory tract infections have a high resistance rate to many antimicrobial agents.In view of the seriousness of this problem,we should emphasis on it and select antimicrobial agents rationally.

BACKGROUND:Myocardial fibrosis following myocardial infarction is an important mechanism of ventricle reconstitution. However, there are few reports concerning effects of myocardial transplantation related to stern cells on this process. OBJECTIVE: To investigate the effects of auto-skeletal muscle satellite cells implanted into ischemic myocardium on myocardial fibrosis in rats with myocardial infarction and their mechanisms.DESIGN, TIME AND SETTING: The randomized controlled animal study was performed at the Third Research Room, Research Institute of Surgery, Daping Hospital, Third Military Medical University of Chinese PLA from July to September 2007. MATERIALS: A total of 45 Wistar rats, of both genders, weighing 150-200 g, were used in this study. Of them, 30 rats were used to establish models of myocardial infarction.METHODS: A total of 45 rats were assigned to 3 groups (n=15). Rats in the myocardial infarction group received ligation of the left anterior descending coronary artery to induce myocardial infarction. 2 weeks later, 0.2 mL serum-free M199 medium was infused into the juncture between infarct region and normal myocardium through multiple points. In the transplantation group, following model induction, 0.2 mL auto-skeletal muscle satellite cells in rats after 2-weeks in vitro culture were transplanted into the surrounding of infarct region. Rats in the sham operation group were not induced to create models, only injected with 0.2 mL saline in the heart anterior wall surrounding the left anterior descending branch through multiple points. MAIN OUTCOME MEASURES: Four weeks after injection, vascular endothelial growth factor mRNA and vascular endothelial growth factor protein expression in the ischemic myocardium was demonstrated. Capillary density changes in the ischemic myocardium were detected. Growth and proliferation of myocardial cells in the infarct region were observed using hematoxylin-eosin staining.RESULTS: Vascular endothelial growth factor mRNA and vascular endothelial growth factor protein expression was significantly decreased in the sham operation and myocardial infarction groups compared with the transplantation group at 4 weeks following satellite cell transplantation (P<0.01). Capillary density was greater in the myocardial infarction group compared with the sham operation group (P<0.05). Capillary density was significantly higher in the rat ischemic myocardium in the transplantation group compared with the sham operation and myocardial infarction groups (P<0.01). Hematoxylin-eosin staining demonstrated that myocardial morphology was normal in rats of the sham operation group, with clear structure, orderly myocardial fibrosis. There were no fibroblastaggregation and hyperplasia among myocardial fibrosis. Fibroblast hyperplasia and collagent formation were found in the rat myocardium in the myocardial infarction group, with disorderly myocardial structure. Myocardial cells with transverse striation and many nuclei were observed in the rat infarct region of the transplantation group, with orderly arrangement. Fibrous tissue was significantly less in the transplantation group compared with the myocardial infarction group.CONCLUSION: Satellite cells can proliferate and differentiate into striated muscle-like cells with flexible and systolic functions in the infarct region. Satellite cells secrete vascular endothelial growth factor and promote blood capillary hyperplasia in ischemic myocardium by autocrine and paracrine, which finally effectively inhibits fibrosis progress in the ischomic myocardium.