BACKGROUND:Scoliosis is a complex spinal pathology characterized as a three-dimensional spine deformity combined with vertebral rotation. The finite element analysis can replace traditional biomechanical experiment for repeated experimental analysis and for processing digital simulation. It has been widely used in the study of scoliotic biomechanics.
OBJECTIVE:To emphasize the application of finite element analysis on the brace and surgical treatment of scoliosis.
METHODS:An online search of PubMed and Wanfang database was performed by using key words of“scoliosis, finite element”in Chinese for articles published between January 1986 and May 2013. A total of 38 papers related to finite element of scoliotic treatment, published in authorized journal and considered to be a representative, were selected.
RESULTS AND CONCLUSION: How to design an individualized brace in accordance with biomechanical characteristics of scoliosis is the hot topic. By using multi-imaging technology, the rib, chest bone and pelvis are introduced into the finite element models, in a broader attempt to analyze the optimal three-dimensional orthopedic force pattern for scoliosis. The results of relative research showed that, the ideal loading pattern is given at the protruding area of scoliosis. Finite element analysis can predict and evaluate the orthopedic procedure and effect of patients, thus assisting the design of reasonable orthopedic treatment scheme. Through finite element analysis, we can simulate and analyze the stress distribution of internal fixator in spine, which contributes to prevent the complications.

Objective To determine the changes of blood cytokines values and inductions of cytokines expressions after CPB and cardiac valve replacement. Methods Thirty patients undergoing cardiac valve replacement were randomly selected, The plasma cytokines levels or activities and inductions of cytokine expressions were measured before CPB, 1st, 3rd, 7th, 14th d after operation.Results Compared with the baselines, IL 1 activity and souluble interleukin 2 receptor(SIL 2R) level increased on the 1st, 3rd d , then decreased significantly on the 7th d, plasma IL 8 level increased in 14 d after CPB, but IL 2 activity decreased during 7 d postoperatively(P0.05); induction of IL 1 expression increased significantly on the 1st d and decreased on the 3rd d (P

Objective To investigate the anatomical and histological features of the rat endolymphatic sac. Methods The temporal bones of the healthy,adult SD rats were removed.The morphology of the endolymphatic sac were studied.Then the decalcified samples were embeded in paraffin.The sections of the endolymphatic sac were stained with HE method and observed histologically,and then examined immunohistochemically by monoclonal antibodies against IgG,CD 3 of the rat to investigate the immunocompetent cells in endolymphatic sac of the rats. Results Simple cuboidal and squamous epithelium were the main types of the epithelium in rat endolymphatic sac CD + 3,IgG + immunoreactive lymphocytes were found mainly in the epithelium of the endolymphatic sac.Conclusion\ The morphology of the rat endolymphatic sac is similar to those of human and guinea pig endolymphatic sacs.Some immunocompetent cells were found in the endolymphatic sac,suggesting that the endolymphatic sac plays an important role in immune of inner ear.\;[

Objective To observe the change of C-reactive protein (CRP), Interleukin-6(IL-6) plasma levels before and after percutaneous coronary intervention(PCI) in angina pectoris patients to evaluate the relationships between the severity of coronary lesions, CRP and IL-6. Methods 36 patients diagnosed as angina pectoris by coronary angiography received PCI and 15 healthy subjects served as the control. Peripheral blood samples were taken before and after PCI, the serum levels of CRP and IL-6 were measured by ELISA. The relationships between serum CRP,IL-6 and the severity of coronary lesions were analyzed. Results The mean levels of serum CRP and IL-6 in the patients were higher than those in the control(P

BACKGROUND:Under the pathological conditions of urethral defect,stricture and diverticulum induce by trauma,congenital malformation,tumor and operation,autogenous tissue are used for defect repair.OBJECTIVE:To verify the feasibility of urethra constructed by tissue engineering.DESIGN,TIME AND SETTING:An observational experiment was performed at Linbaixin Medical Research Center,Sun Yat-sen University,from January 2005 to January 2006.MATERIALS:Ten New Zealand rabbits weighing 3.0-3.5 kg were used to prepare acellular urethras.Twenty BALB/cA-nude mice weighing 18-20 g,4-6 weeks old,were cultured with extracellular matrix materials in vivo.METHODS:The whole urethra harvested from New Zealand rabbit prepared the extracellular matrix materials by acellular treatment.Half a glans harvested from adult New Zealand rabbit was used for smooth muscle cells proliferation by tissue explant.The corpus spongiosum smooth muscle cells were implanted in acellular matrix materials.Then,they were cultured by subcutaneous embedding in nude mice.There were two groups in the experiment:experimental and control.The complexs of corpus spongiosum smooth muscle cells implanted in acellular matrix materials were embedded in the experimental group,while the simple acellular matrix materials were embedded in the control group.MAIN OUTCOME MEASURES:After 1,2,4,6,8 weeks of embedment,the growth of the complexs were examined by gross,histologic and electron microscopic observation.The expression of smooth muscle cells were identified by immunohistochemistry method.RESULTS:①Under the gross observation,incisions on the back of the nude mice healed well,the diets and activities of the nude mice were normal.In the experimental group,there were thin tissue membranes on the surface of the acellular matrix materials at 1-2 weeks after the embedment.The thickness of tissue membrane increased gradually and there were small blood vessels grown at 4 weeks.The new cells were instead of acellular matrix materials at 6-8 weeks.②Under HE straining,the acellular matrix materials were absorbed.Various cells,most of them were smooth muscle cells,would be instead of the acellular matrix materials.And unequal blood vessels grown in matrix materials,most of them had the trend of blood sinus formation.These results suggested that the complexs formed the structure similar to normal urethra in the nude mice.③Under the electron microscopic observation,there were blood vessels grown in the matrix materials from 4 weeks after embedment.More smooth muscle cells,endothelial cells,and little fibroblast cells,macrophages were observed,as well as some apoptotic smooth muscle cells.④After immunohistochemical staining of ?-smooth-muscle actin antibody,the growth of smooth muscle cells could be observed.CONCLUSION:The corpus cavernosum tissue similar to normal urethra can be constructed by using tissue-engineering technique.

Aim To explore effects of TCS on the gene expression profiles of human cervical carcinoma HeLa cells with microarray technique and further investigate its molecular mechanism. Methods RNA from both control and treated HeLa cells were isolated and reversely transcribed to cDNA with the incorporation of cy3 and cy5-labeled dUTP, probes were hybridized with BiostarH-Ⅰ cDNA microarray, chips were scanned and then analyzed by GenePix Pro 3.0 software. Results 78 significantly differently expressed genes were screened out of which up-and down-regulated genes were 62 and 16 respectively. the up-regulated genes were closely related with apoptosis (such as NOP56、TNFSF10、CASP9、DFFB,etc) and the down-regulated genes were associated with the adhesion and interaction between cells (such as COL9A3、LGALS3BP、 MGST3,etc). Conclusion TCS could result in differential expression of multiple genes in HeLa cells, and DNA microarray technique can provide valuable insight into the molecular mechanism of TCS-induced apoptosis.

Objective To investigate the value of perfusion MR imaging in differential diagnosis between primary central nervous system lymphomas(PCNSL)and high grade astrocytomas.Methods Twelve patients with PCNSL and 23 patients with high grade astrocytomas were preoperatively examined using a 1.5T MR unit.Routine MR sequences were performed followed by dynamic susceptibility contrastenhanced MR perfusion imaging.The perfusion color images and the time-signal intensity curves of the two tumor groups were compared.The relative cerebral blood volume(rCBV)within the tumor parenchyma was measured and the data were analyzed with unpaired Student's t-test.Results The rCBVs within the tumor parenchyma of the PCNSL and high grade astrocytomas were 1.78±0.5 1 and 3.87±0.87 respectively.The rCBV in the PCNSL was significantly lower than that of the high grade astrocytoma(P＜0.05).When the time-signal intensity curves were compared,the PCNSL showed a trend towards the baseline after the first pass and the curves even overshot above the baseline in 7 out of 12 cases,whereas the high grade astrocytoma showed a trend to be close to the baseline but couldn't return to the baseline completely.Conclusion The MR perfusion imaging can be very useful in distinguishing the PCNSL from high grade astrocytomas.

Objective To evaluate whether therapeutic ultrasound, applied alone or with urokinase, may have a thrombolytic effect on blood clots in vitro, and the other factors influencing the urokinase-mediated thrombolysis. Methods Experiments were carried out in an in vitro blood clot model.The blood clots were divided into four groups as physiological solution group(NS), urokinase group(UK),physiological solution plus ultrasound group(NS + US), urokinase group plus ultrasound group(UK + US).After intervention of one hour in static 37 ℃ water bath, each group of blood clots was weighed. After that,the weight loss and thrombolysis rate of the blood clots in each group were calculated. To observe the impact of the age of the blood clots on urokinase-mediated thrombolysis rate, the thrombolysis rate of eight time points 3, 4, 5, 6, 7, 8, 9, 10 hours was tested. The time was determined from the blood drawn from the body to the initiation of thrombolysis test. Results In terms of thrombolysis rate, there was significant difference between UK group and UK + US group(LSD-t 12. 1, P ＜ 0.01), with a thrombolysis rate 29. 3% ±8. 2% and 37. 5% ±7. 9%, respectively. However, the difference of thrombolysis rate between NS group and NS + US group with a thrombolysis rate 13. 4% ±4. 4% and 14. 5% ± 5.4%, respectively,was not statistically significant with a P value of 0. 08(LSD-t 1.8). The age of the blood clots had a negative correlation to the thrombolysis rate to some extent. Conclusion Therapeutic ultrasound has a significant effect on thrombolysis in combination with urokinase rather than used alone. To a certain extent,the thrombolysis rate decreases with the age of blood clot.

BACKGROUND: Bone marrow mesenchymal stem cells (BMSCs) have a remarkable differentiation potential and superiority as a type of seed cells,but their application is limited in the presence of certain diseases,such as aplastic anemia and myelogenous neoplasm.The present studies have found that seed cells called muscle-derived stem cells (MDSCs) have brought more and more attention,because of their capability of stir-renewal and multi-diffcrentiation like B MSCs.OBJECTIVE: To explore the biological characterization of the muscle-derived stem cells (MDSCs) from rabbits,and analyze the phenotype.DESIGN,TIME AND SETTING: Cell in vitro observation experiment was performed at the Medical Research Center of Second Affiliated Hospital of Sun Yat-sen University from August 2005 to March 2006.MATERIALS: A New Zealand rabbit (1.5 months old,clean grade) was enrolled for the preparation of Muscle-derived stem cells.Growth medium was DMED-LG added with 10% fetal bovine serum and 10% horse serum and fusion medium was DMEM-LG added with 2% fetal bovine serum.METHODS: The muscle mass was removed from the anesthetized rabbit to isolate MDSCs.These cells were dissociated using three enzymes (collagenase XI,dispase and trypsin) respectively.Sediment was resuspended.Then preplate technique was used.The muscle cell extract was plated on a collagen-coated culture flask with growth medium.The flask was called PP1.PPI was kept overnight in a 37 ℃ incubator containing 5% CO2,After that,the suspension was transferred to another collagen-coated culture flask,which was called PP2.PP3,PP4,PP5 and PP6 were constructed later following the same procedures.The cells adhered in PP6 were collected,plated in 6-well plates,and divided into 2 groups.Growth medium was used in one group,in which the cells were kept growing at a degree of confluence beyond 50%,and fusion medium was used in the other one,in which the cells were passaged with a degree up to 30%.MAIN OUTCOME MEASURES: The cells from PP1 to PP6 were collected,and the characterization was identified preliminary by Flow cytomctry,Immunocytochemistry and Western Blotting.The fusion of cells in PP6 was detected at different confluence degrees and concentration of medium.RESULTS: The cells in PP6 showed ＞ 80% desmin+,＞ 70% Bcl-2+,＞ 95% CD45,which indicated that MDSCs were in a high concentration.The expressions of α-SMA in the cells were decreasing with the Preplate technique used and the cells in PP6 almost had no α -SMA expression.When passaged at a high confluence (＞ 50%) or cultured with low concentrations of serum (2% serum),the cells in PP6 had a strong tendency of fusing into myotubes or cell chains and were skeletal myosin+.CONCLUSION: MDSCs,which are capable of multi-differentiation under a high fusion or low serum conditions,express dcsmin and Bcl-2 highly,but extreruelv little CD45 and no α -SMA.

BACKGROUND: Hyperbaric oxygen may induce cerebral infarction. But what kind of medicine may prevent it and what is the preventive function of the medicine are not clear yet.OBJECTIVE: To compare the preventive function of nitrates with calcium antagonists in cerebral infarction induced by hyperbaric oxygen.DESIGN: Controlled retrospective observation based on patients.SETTING: Department of Hyperbaric Oxygen, Department of Neurology,Guangzhou General Hospital of Guangzhou Military Area Command of Chinese PLA.PARTICIPANTS: Totally 192 patients receiving hyperbaric oxygen treatment in Guangzhou General Hospital of Guangzhou Military Area Command of Chinese PLA, who were 127 males and 65 females, and aged 9 -78 years old. Among them, 6 patients developed into cerebral infarction.METHODS: Totally 192 patients receiving hyperbaric oxygen treatment were old, hypertensive disease, hyperlipemia, cerebral infarction(or cerebral hemorrhage), hyperviscosity in blood and diabetes as dangerous factors, prevention function of medicine was analyzed on the level of grouping different dangerous factors.INTERVENTIONS: Under the prerequisite condition of regular treatment medicine given to the 192 patients of the 3 groups, patients in nitrate group took isosorbide dinitrate or nitroglycerin orally, patients in calcium antagonist group took sibelium or Norvasc and so on orally, and patients in group without special medication did not take preventive drugs.MAIN OUTCOME MEASURES: Dangerous index was dangerous factorsto cerebral infarction.RESULTS: No one developed into cerebral infarction with grouping less than 4 dangerous factors. On the level of grouping 4 or more dangerous factors,nitrates had good preventive function, but in calcium antagonist group,33.3% patients developed into cerebral infarction. There was significant difference between them( P ＜ 0.05).CONCLUSION: Nitrates have significant preventive functions, but calcium antagonists have no such functions.