Objective To investigate the morphological effect of fluid shear stress on pig iliac endothelium cells cultured solely or co-cultured with pig small intestinal submucosa.Methods The shear stress of 40×10-5 N/cm2 were carried out for 12 h on both groups.The images were recorded every 30 min.The directional angles were calculated.Results In the group of cell cultured solely:The defluvium of cells was obvious at the 1st hour,but the shape of cells didn't change.At the 4th hour,the defluvium of cells was little,the cell became round from its initiatory polygon shape.At the 8th hour,the defluvium of cell could not be observed.The shape of cells became fusiform and gracile.The cells arranged along the direction of flow field in the local area.At the 12th hour,the cells became more and more gracile.The trend of realignment of cells along the direction of flow field was obviously.The directional angles of cells at the 12th hour was significantly different from the zero hour.In the group of cell co-cultured with small intestinal submucosa:At the 1st hour,some of cells were brushed off mildly.The defluvium of cells could not been observed since the 2nd hour.The directional angles didn't change significantly in the 12 hours.Conclusion The shear stress of 40×10-55 N/cm2 cannot influence the cell of co-cultured but do influence the cell cultured solely.

Objective To investigate the effects of transient receptor potential vanilloid 1 activation by capsaicin on the oxidative stress in lipopolysaccharide-induced lung injury in mice in order to elucidate the potential mechanisms.Methods A total of 108 specific pathogen free (SPF) ICR male mice were randomly divided into six groups:normal control group (n =18),capsaicin control group (CAP control group,n =18),capsazepine control group (CAPZ control group,n =18),acute lung injury group (n =18),capsaicin treatment group (CAP treatment group,n =18) and capsazepine treatment group (CAPZ treatment group,n =18).After modeling,superoxide dismutase (SOD),catalase (CAT) and malondiachehyche (MDA) levels in lung were measured with the method of chromatometry,and the expression of heme oxygenase 1 (HO-1) in lung tissue was assessed with enzyme linked immunosorbent assay (ELISA),while the level of NF-E2-related factor-2 (Nrf2) was determined by western blotting and the expression of Nrf2 mRNA was measured by RTPCR.Pathological changes of lung tissue were observed under light microscope.Results The activities of SOD and CAT in lung tissue at 3,8,16 h were dramatically lower in acute lung injury group than those in normal control group (P ＜ 0.05),while the level of MDA was higher.Compared with acute lung injury group,the lung levels of SOD and CAT at 8 h and 16 h were higher in CAP treatment group (P ＜0.05),while the lung level of MDA was lower (P ＜ 0.05).The levels of SOD and CAT in CAPZ treatment group were decreased at 8 h and 16 h,while the levels of MDA in this group were increased at 3,8,16 h (P ＜0.05).The pulmonary levels of HO-1,Nrf2 and expression of Nrf2 mRNA were significantly higher in acute lung injury group than those in normal control group (P ＜ 0.05).Compared with acute lung injury group,the levels of HO-1,NRF2 and expression of NRF2 mRNA were increased markedly in CAP treatment group (P ＜ 0.05)and were obviously decreased in CAPZ treatment group (P ＜0.05).At 8 h,16 h after modeling,the degree of lung damage was ameliorated in CAP treatment group compared with acute lung injury group under light microscope,while the lung damage was aggravated in CAPZ treatment group.Conclusions The activation of TRPV1 could apparently up-regulate the levels of CAT,SOD,Nrf2,HO-1,and reduce the MDA level in lung tissue of mice with acute lung injury,ultimately protecting the endotoxemia mice from oxidative stress.

Total hip replacement is a very effective method to cure many kinds of hip joint illnesses. About a century ago, it was first used in clinic. Since then, total hip replacement has been well developed. Hip joints sustain the most load of body, so people pay great attention to the hip prothesis' mechanics property. Especially after the finite element analysis was widely used in biomechanics investigation, the stress distribution of different designs can be easily compared with each other, and the relatively better parameters of the design could be decided. The stress distribution of different materials with the same design also can be valued. However, studies have indicated that total hip joint replacement still has some disadvantages. Loosening of the hip prothesis is still the most likely cause of the failure of surgery, and generally this is believed to stem from either mechanical failure of the fixation in response to over high density stresses, or osteolysis of the surrounding bone stock responsing to particular wear debris. Many researchers on computational studies have considered the potential for the former one, but only a few have attempted to tackle the latter. The process of osteolysis of the bone is not yet completely known. Nowadays, in order to solve the problems of loosening, investigators are trying to find different methods. Some of them are working on improving the geometry parameters and the shape of the hip prothesises, some are trying to find new suitable biomaterials, and, at the same time, the fixation methods are under deliberation.
Arthroplasty, Replacement, Hip ; adverse effects ; Computer-Aided Design ; Finite Element Analysis ; Humans ; Prosthesis Design ; Prosthesis Failure ; Stress, Mechanical ; Weight-Bearing

Objective To compare the value of "linear shadow" of posterior vertebral body wall under standard lateral X-ray fluoroscopy and CT scan in evaluating the reduction of bone fragment retro-pulsed into the spinal canal so as to provide evidence for indirect reduction degree of bone fragment under X-ray fluoroscopy during operation. Methods A retrospective study was done on 25 cases of thoraco-lumbar burst fractures treated at our department. There were 15 males and 10 females, at age range of 24-66 yeas(average 44. 9 years). Preoperative CT scan confirmed burst fractures in all cases. Bone frag-ment occupied mearl 35. 2% of midsngittal diameter of injured segment. All cases were treated by indirect reduction with short-sesment pedicle instrumentation, rather than laminotomy or partial laminectomies. When imging of posterior vertebral body wall manifested a continuous and smooth"linear shadow" under standard lateral X-ray fluoroscopy during operation, bone fragment War considered to be under reduction. CT span was performed to evaluate the reduction of bone fragment postoperatively. Results The bone fragment occupation of midsngittal diameter of injured segment was decreased from preoperative 35. 2%to postoperative 8. 6%, with statistical difference(t=9. 122, P<0. 01). Neurological function of all 25 cases was normal at last follow-up. The decompression of spinal canal was effective. Conclusions A continuous and smooth"linear shadow"on posterior vertebral body wall imaging is a simple and effective way to judge the reduction of bone fragment retropulsed into the spinal canal and can provide evidence for whether laminotomies and pushing bone fragment are necessary during operation.

ObjectiveTo explore the therapeutic effect of selective antagonist-AM630 of cannabionid receptor 2 (CB2) in treatment of the titanium particles-induced inflammatory osteolysis.MethodsForty-five female BALB/c mice, 6-8 weeks old, were involved in the study, of which 15 mice were used as skull donors and the rest experimental animals were randomly divided into three groups, ie, black group, control group and treatment group, 10 mice per group.The mice model with air-pouch osteolysis induced by the titanium particles were established.The mice in the treatment group were injected with CB2 selective antagonist-AM630 (200 μg · kg-1 · d-1) intraperitoneally from two days before establishment of the air-pouch osteolysis model to two weeks after establishment of the model.Then, the mice were sacrificed and the pouch tissues were collected for molecular and histological analyses.The pouch membrane thickness and cell infiltration were tested by using computerized image analysis system and HE staining respectively.Osteoclast-like cells in the pouch membrane were determined by using tartrate-resistant acid phosphatase (TRAP) staining.Quantitative real-time polymerase chain reaction (RT-PCR) was employed to detect the mRNA levels of CB2, IL-1 β, TNF-α, receptor activator of NF-κB ligand (RANKL)and receptor activator of NF-κB (RANK).ResultsThere exhibited apparent erythematous and oedematous changes in the control group, which was mitigated around the bone implants with AM630 treatment.Quantitative image analysis of the histological sections revealed significant difference of the pouch membrane thickness among three groups, (192.2 ± 19.4)μm in control group, (88.5 ± 14.7) μm in blank group and (122.1 ± 15.2) μm in treatment group (F = 101.74, P ＜ 0.05).Intensive TRAP staining was identified much in the control group but markedly reduced after AM630 treatment in the pouch tissues.RT-PCR showed that titanium particle stimulation could enhance the expressions of CB2, IL-1 β, TNF-α, RANKL and RANK gene in the air pouch tissues.However, the mRNA levels of these genes were markedly reduced after AM630 treatment, with statistical difference compared with control group (P ＜ 0.05).ConclusionsCB2 selective antagonist AM630 can inhibit the process of titanium particlesstimulated inflammatory reaction and osteoclast activation.Therefore, CB2 represents a new suitable therapeutic candidate for the prevention and treatment of aseptic loosening of the artificial joint.

Objective To explore the effect of body-weight support treadmill training(BWSTT)on lower extremity muscle atrophy and ambulatory capacity in complete spinal cord injured(SCI)patients.Methods 20 patients with complete SCI at the thoracic level were divided into control and BWSTT group.They all received comprehensive rehabilitation,and patients in BWSTT group also received BWSTT for 3 months when the physical condition was permitted.They were assessed before and after treatment with measurement of thigh girth,ambulatory capacity measure of Functional Independence Measure(FIM),10 meters ambulatory velocity and activity of daily living(ADL)evaluation.Patients in BWSTT group also received middle thigh MRI examination before and after BWSTT.Results The muscles at the mid-thigh of the BWSTT group looked larger after BWSTT than before.The scores of FIM ambulatory function,the 10 miters ambulatory velocity of BWSTT group improved significantly when compared with that of the control group(P<0.05).The thigh girth and the scores of ADL were no different between these two groups before and after treatment(P<0.05).Conclusion BWSTT may ameliorate lower extremities skeletal muscle atrophy and improve ambulatory capacity for SCI patients.

One hundred and fourty-nine normal persons were tested to gain the normal scale of Comprehensive Function Evaluation(CFE).It includes seven items eighteen categories.The result demonstrated that fifteen categories of normal persons in age of twenty to sixty-nine incuding understanding and expressing,feeding,grooming,dressing clothes,dressing trousers and skirts,bathing,bowel and bladder management,control of sphincter of bowel and bladder,bed wheelchair mobility,bathtub-wheelchair mobility,ambulation,up and down the stairs,which gained one hundred degrees each,memory ninty eight to one hundred degrees,problem solving ability eighty-four to one hundred degrees,social communication ninty-nine to one hundred degrees.We conclude preliminarily:CFE is an individual ability evaluation of preson,demonstrating the comprehensive function of presons which were in aga of twenty to sixty nine,educated in and above primary school.It can be used as a main scale to evaluate the guality and effect of rehabilitation sequence,and has practical value to improve rehabilitation medical level.

Presented in this paper is a preliminary report on reliability study of comprehensive function evaluation.One hundred and five normal persons were evaluated twice in the interval of one month.The result revealed significant statistical difference,Kappa=0.79,u=7.938>2.56,P<0.01,demonstrating the substantial agreement of these two evaluations.The result suggests that the scale has substantial intra observer agreement and high reliability.The personal comprehensive function could be evaluated completely in the scale.It would be significant not only in practice but also in theory to improve the rehabilitation evaluation and rehabilitation medical level.

A model of fluid dynamics related to the myocardial bridginged and mural coronary artery was designed and manufactured according to the physical principle and characteristic of the mural coronary artery. The model can imitate systematically well the effect of myocardial bridging on hemodynamic change of the mural coronary artery under different controlled experimental parameter. The methodology is proved to be feasible and has good prosperity of experimental study.
Coronary Vessels ; physiology ; Hemodynamics ; Humans ; Models, Cardiovascular ; Myocardial Bridging

Objective To compare the apparent diffusion coefficients (ADC) between healthy people and patients with early cervical spi nal cord injury (SCI). Methods 18 patients with early cervical SCI and 5 healthy controls were examined with MRI T1WI, T2WI and DWI, and the ADC values and ADC maps were obtained. Results and Conclusion ADC values were less in the patients than in the healthy con trols, and the cut-off point was 800.0×10-6 mm2/s. ADC values also reduced in some patients without obvious abnormal MRI finds.