BACKGROUND:Vertebral compression fractures are the most common vertebral fractures in the elderly patients with osteoporosis, and the correlation between the compression of anterior border of vertebral body and adjacent vertebral refractures is not clear.
OBJECTIVE:To establish a model of different compression of T12vertebral body with finite element method, and analyze the relationship between the compression of T12vertebral body and the stress of adjacent vertebral plate.
METHODS:Based on thoracolumbar CT data of normal adult volunteers, MIMICS/3-matic was imported. Through image segmentation, repair and three-dimensional mesh of accessto thoracic and lumbar T11-L1data, grid assigned material properties was imported to ABAQUS so as to establish ligament, joint and other small features and obtain realistic three-dimensional finite element model. The six degrees of freedom, including anteflexion, posterior extension, left and right flexion, left and right rotation, were loaded, to verify the validity of the normal model. With the frontier of vertebral body compression to 90%, 80%, 70%…10% of the nine states, MISES stressesof the T11andL1segment intervertebral disc endplate were extracted; the relationship curve of compression state and endplate stress was obtained.
RESULTS AND CONCLUSION:(1) The model was highly realistic and could reflect the actual stress state. (2) The stress value of T11vertebral body and L1vertebral body was positively correlated with the compression of T12vertebral body. Increased stress may lead to an increased likelihood of end plate fractures, which increases the risk of fractures in the adjacent vertebralbodies.

Objective To explore whether obese adolescents had neurochemical abnormalities in frontal lobe and hippocampus.Methods Anthropometric indicators were measured in all participants.Proton magnetic resonance spectroscopy(1H-MRS)were performed in 9 obese adolescents and 9 non-obese children as controls.Spectral peaks of N-acetylaspartate(NAA),creatine(Cr),choline(Cho)of 2 cortexes were measured and their ratios were computed and compared.Results Values of NAA and Cho in frontal lobe in obese group were significantly lo-wer than those of controls.There was no significant difference of Cr,NAA/Cr,Cho/Cr in frontal lobe and hippocampus between 2 groups.Conclusion The reduced NAA and Cho on 1H-MRS suggests that amount of neural nerve and myelination of white matter may be harmed in frontal lobe of obese adolescents.

A computerized stabilometer was used to evaluate the balance function of 31 subjects with healthy backs and 3l subjects with chronic low back pain. According to the difference of age and sex,they were divided into 2 groups equally. They were told that the feet stood side by side and stood separately with eyes opened and closed. The sensitivity and applying value of all of the test parameters were analyzed. The result showed that the stabilization of the subjects with chronic low back pain was poorer than the healthy subjects. The parameters, such as Sx, Sy, MS, PL, CA and AS, were sensitive, and feet stood side by side was more sensitive than feet stood separately.

Objective To investigate the protective effects of simvastatin on cobalt choride ( CoCl2 ) -induced hypoxia and reoxygenation injury on alveolar type Ⅱ cells and the underlying mechanisms.Methods CoCl2 was used to establish the hypoxia and reoxygenation injury model on AT Ⅱ cells.Blank,control and variant doses simvastatin-treated groups ( 5,10,20,30,50,100 μ mol/L) were designed in the present study.The proliferation of AT Ⅱ cells was evaluated by Cell Counting Kit-8 ( CCK-8 ) assay.The percentage of apoptotic cells was assessed by flow cytometry AV/PI double-staining.The protein levels of surfactant protein-C (SP-C) and proliferating cell nuclear antigen (PCNA) in AT Ⅱ cells was determined by Western blot.Results As compared with the control group,pretreatment with low dose (5 - 20 μmol/L),but not high dose simvastatin (50 - 100 μmol/L) markedly reduced A549 cells apoptosis,and increased their proliferation and the protein levels of SPC and PCNAin vitro.The protective effect could be reversed in vitro by L-mevalonate,a simvastatin competitive inhibitor,which indicated that the inhibition of mevalorate pathway was involved in the simvastatin induced AT Ⅱ cells function restoration.Condusion Low doses simvastatin reversed CoCl2-induced hypoxia and reoxygenation injury of AT Ⅱ cells.The inhibition of mevalonate pathway contributed to simvastatin induced AT Ⅱ cells function restoration.

Objective:To explore changes of central retinal vascular caliber and fractal dimension (Df) and their cor‐relation with blood pressure in hypertensive population .Methods :A total of 2169 subjects>30 years old were en‐rolled in this cross‐sectional study .They were divided into hypertension group (n=819) and non‐hypertension group (n=1350) .Fundus photos were collected in all subjects ,and semi‐automatic software was used to quantitatively ana‐lyze central retinal vascular caliber and Df ,and they were compared between two groups .Results:Compared with non- hypertension group ,there were significant reductions in central retinal arteriolar equivalent [CRAE ,(135.2 ± 10.72) μm vs .(132.25 ± 11.56) μm] ,central retinal venular equivalent [CRVE ,(184.95 ± 16.29) μm vs . (182.52 ± 17.07)μm] and Df [ (1.38 ± 0.05) vs .(1.34 ± 0.05)] in hypertension group , P<0.01 all .After adjus‐ting for age and gender ,analysis of covariance indicated that CRAE and Df of hypertension group were still signifi‐cantly lower than those of non - hypertension group (P<0.01 both) .Linear correlation analysis indicated that sys‐tolic blood pressure (SBP) ,diastolic blood pressure (DBP) and pulse pressure (PP) were inversely correlated with CRAE and Df ( r= -0.340~ -0.174 , P<0.01 all) .After adjusting for cardiovascular risk factors ,multi‐factor linear regression analysis indicated that CRAE and Df were still inversely correlated with SBP ,DBP and PP (stand‐ardizedβ= -0.190~ -0.134 ,P<0.01 all) .Df of hypertension course >5 years group was significantly lower than that of ≤5 years group [ (1.33 ± 0.05) vs .(1.35 ± 0.05)] , P<0.01. Conclusion:CARE ,Df are significantly in‐versely correlated to SBP ,DBP and PP in hypertensive population ,while correlation of Df is most .

AIM: To identify the non-steroid transcription factors upregulating the expression of L-plastin in hormone-independent prostate cancer, and partly elucidate the mechanism of hormone-refractory prostate cancer. METHODS: TF SEARCH software was used to analysis the possible binding sites of transcription factors in the 3’ end of L-plastin promoter that had been identified as important part of regulation response elements. Gel shift assay and supershift assay were used to confirm the transcription factors binding the speculated response elements. PCR site-mutagenesis technique was performed to delete the binding site of transcription factor and luciferase activity assay was carried out after deletion of the binding site. RESULTS: SP-1 respond element GGTGGGGCGGGGA located at -54- -41 of L-plastin promoter was identified with the TF SEARCH software. Gel shift assay and supershift assay confirmed that SP-1 was the transcription factor binding to GGTGGGGCGGGGA. Mutant deleted the SP-1 binding-site had low-luciferase activity than that of the naive. CONCLUSION: SP-1 plays an important role in the up-regulation of L-plastin expression in hormone-independent prostate cancer.

OBJECTIVETo explore the mechanisms involved in the ligustrazine alleviation of the pulmonary artery hypertension (PAH) in patients of chronic obstructive pulmonary disease (COPD) associated with chronic cor pulmonale (CCP) during exacerbation.

METHODSSeventy patients of COPD and CCP with acute exacerbation were randomly and equally divided into control group and treatment group. The control group received standard treatment with antibiotics, antiasthmatic and expectorant medications, and oxygenation; and the ligustrazine treatment group received ligustrazine treatment (80 mg/d; i.v.; for 2 weeks) in addition to the standard treatment. Before and at the end of 2 week treatment, the clinic responses of the two regimens were evaluated, plasma levels of endothelin-1 (ET-1) and nitric oxide (NO) were determined; arterial oxygen partial pressure (PaO2, mean pulmonary arterial pressure (mPAP), outflow tract of right ventricle (RVOT), and internal diameter of right ventricle (RV) were measured.

RESULTSGood clinic benefits were achieved in both the standard and ligustrazine regimens, plasma level of ET-1, values of mPAP, RV and RVOT decreased significantly, plasma level of NO and PaO2 values decreased (all P < 0.01 vs pre-treatment to all parameters). Compared with the control group, ligustrazine greatly enhanced the clinic efficacy from 77.1% to 97.1% (P < 0.05), and also resulted in more significant changes of all these parameters (P < 0.01 vs control group for all parameters). For both groups, the levels of plasma ET-1 were positively correlated with values of mPAP, RVOT, and RV (r = 0.710, 0.853, and 0.766, respectively, all P = 0.000), and negatively correlated with plasma NO and PaO2 (r = - 0.823, and - 0.752, respectively, all P = 0.000).

CONCLUSIONLigustrazine is effective in treating pulmonary artery hypertension during acute exacerbation of COPD and CCP in patients from the plateau area. The observed changes in the plasma levels of NO and ET-1 in response to ligustrazine treatment suggest that ligustrazine may act through the selective effect on pulmonary blood vessels to enhance the synthesis and release of NO and suppress those of ET-1 from lung vascular endothelial cells, thus reducing pulmonary artery pressure and decreasing pulmonary arterial hypertension.

Altitude ; Blood Gas Analysis ; Chronic Disease ; Endothelin-1 ; blood ; Humans ; Hypertension, Pulmonary ; drug therapy ; Nitric Oxide ; blood ; Pulmonary Artery ; physiopathology ; Pulmonary Disease, Chronic Obstructive ; drug therapy ; Pyrazines ; therapeutic use ; Respiration

Microbial lipase,one of important industrial biocatalysts,has been used widely in many industrial and agricultural fields.It is always the research focus to screen,mine and develop the microbial lipases with novel catalytic activity and high stability.This paper introduces briefly the pathways and methods to mine novel microbial lipase resources from six aspects,including extremophile,metagenome,genome database,protein engineering,immobilization,chemical modification,etc.

Microbial lipases are important industrial biocatalysts with the character of stereoselectivity,site selectivity and high catalytic activity with few side effects.They have been used widely in many industrial and agricultural fields.The technology of protein engineering has been successfully applied to improve the activity and stability of microbial lipases,which will raise the competitive capacity of microbial lipase preparations and enlarge theirs application fields.The strategies,the problems and the prospects of protein engineering technology which have been applied to modify the microbial lipases was surveied.

Objective To study the gait of children with spastic cerebral palsy (SCP) using plantar pressure measurement (PPM).Methods Twenty SCP children and 84 healthy children were recruited,and PPM was used to compare their gait cycle time,cadence,and standardized gait cycle parameters.Results Compared with the control group,gait cycle times in the SCP group were obviously prolonged,and their cadence was significantly slower.The side support phase and swing time in the SCP group were shorter,while the double support phase was longer than that of children in the control group.Conclusion PPM can be used to assess the gait of SCP children efficiently.