1.Finite element analysis of anteroposterior integration fixation by posterolateral nail-stick system for thoracolumbar disorders
Chinese Journal of Tissue Engineering Research 2014;(40):6531-6535
BACKGROUND:Currently thoracolumbar fixation techniques have its advantages and disadvantages, it is necessary to explore a new internal fixation to fix the spine effectively and conveniently.
OBJECTIVE:To establish thoracolumbar (T12-L2) three-dimensional finite element model and observe the effect of anteroposterior integration fixation by posterolateral nail-stick system on thoracolumbar stability.
METHODBased on the CT scan data of normal human T12-L2 segments, we used Geomagic 11.0, Ug 7.0, Hypermesh 10.0, Abaqus 6.9.1 software to establish a three-dimensional finite element model of T12-L2 segments. Subsequently we established nail-stick system posterior fixation, anterior fixation, posterolateral anteroposterior integration fixation model. T12 segment was given 500 N preload and 7.5 N·m torque, to simulate thoracolumbar flexion, extension, lateral bending and rotation. The average rigidity of fixed segments under different conditions were observed.
RESULTS AND CONCLUSION:Three fixation models showed a higher average rigidity than normal model under different conditions. The average rigidity in anteroposterior integration fixation by posterolateral nail-stick system was increased by 13%, 28%, 11%, 17%and 9%, compared with simple posterior fixation under the conditions such as anterior flexion, lateral bending and lateral rotation, respectively. Under the posterior extension, the average rigidity was reduced by 6%than the posterior fixation. Compared with the anterior fixation, the average rigidity in anteroposterior integration fixation by posterolateral nail-stick system was reduced by 15%, 10%, and 14%under the conditions of anterior flexion and lateral bending. While the average rigidity was higher than anterior flexion under the posterior extension and lateral rotation, increasing 5%, 12%and 2%. The anteroposterior integration fixation by posterolateral nail-stick system can improve the stability of fixed segments, and the stability is higher than anterior fixation at posterior extension and lateral rotation, while higher than posterior fixation in anterior flexion, lateral bending and lateral rotation. So it is a potential fixation method.
2.Aspirin in the prevention of colorectal cancer
Journal of International Oncology 2013;(1):68-71
A large nunber of studies show that aspirin and other non-steroid anti-inflammatory drugs (NSAID) have chemopreventive effects on several cancer type s,and more specifically in colorectal cancer.Aspirin can help prevent colon cancer,which has a specific advantage of drug prophylaxis.Studies found that aspirin play different roles on high-risk,moderate-risk and low-risk populations in time and dose.There is limited evidence about the influence on incidence of adenoma among the general risk populations.
3.Effects of extraction orthodontic treatment on the upper airway dimensions in young adult patients with malocclusion
Kefeng XU ; Wei CHEN ; Yuehua LIU
Journal of Practical Stomatology 2001;0(03):-
Objective:To investigate the effects of extraction orthodontic treatment on the upper airway dimensions in young adult patients with malocclusion,and to evaluate the relationship between changes in the craniofacial morphology,position of incisor and upper airway dimensions.Methods:26 patients with upper and lower first premolar extraction and 21 patients without extraction were recruited.Cephalometry and dental cast analysis were performed pretreatment and posttreatment.Results:No statistical difference was found in the parameters of the upper airway dimensions in both non-extraction group and extraction group after treatment.In linear correlation analysis,SPAS was positively correlated with cephalometric variables U1-Y and L1-Y.MAS and IAS was positively correlated with cephalometric variables SNB,U1-Y and L1-Y.The multiple regression analysis revealed that the change of U1-Y had a significant positive effect on SPAS and IAS,and the change of L1-Y also had a significant positive effect on SPAS and MAS.Conclusion:The upper airway dimensions can not be altered during extraction orthodontic treatment,while the changes of incisors are significant associated with the change of the upper airway dimensions.
4.Construction and Expression of Hepatocellular Carcinoma-Specific Expressing Eukaryotic Vector for Anti-Angiogenesis Therapy
Hongyong XU ; Li XU ; Jianhong GAO ; Kaizong LI ; Kefeng DOU
Chinese Journal of Bases and Clinics in General Surgery 2004;0(01):-
Objective To construct a mammalian vector encoding angiostatin kringle 5 (K5) under the control of ?-fetoprotein (AFP) enhancer and albumin promoter, and to observe the expression of angiostatin by introducting angiostatin gene into hepatocellular carcinoma cells through gene transfection. Methods Angiostatin cDNA was amplified from normal human eukaryotic cells by using RT-PCR. Meanwhile, AFP enhancer and albumin promoter sequences were directed cloned and were inserted into vector pcDNA3.1. The recombinant vector of pcDNA3.1-AFAB-angiostatin K5-His was constructed, which contained the angiostatin K5 cDNA sequence that was under the control of the AFP enhancer and promoter. Angiostatin K5 cDNA was introduced into human AFP positive hepatocellular carcinoma cell lines with the transfected cultured cells that were mediated with Lipofectamine 2000. The expression of angiostatin K5 was analyzed by Western blot and the protein was dectected with anti-His antibody. Results The 500-base pair of angiostatin K5 was in accordance with the expected sequence and the recombinant vector of pcDNA3.1-AFAB-angiostatin K5-His was also confirmed as the anticipated sequence. The expression of angiostatin K5 in AFP positive hepatocellular carcinoma cells was detected both by SDS-PAGE and Western blot. Conclusion Efficient construction and expression of angiostatin K5 to AFP positive cells make it possible for antiangiogenesis therapy of human hepatocellular carcinomas, which may provide a promising approach.
5.Posterior hip dislocation combined with femoral head fractures:effects of typing and repair methods
Zhangyong TAN ; Jianliang WANG ; Feng GUO ; Weifeng LIU ; Kefeng XU
Chinese Journal of Tissue Engineering Research 2014;(13):1975-1980
BACKGROUND:Posterior hip dislocation combined with femoral head fractures easily induced femoral head necrosis, ectopic ossification, osteoarthritis and deep vein thrombosis. Different therapeutic methods should be utilized according to the type of fracture.
OBJECTIVE:To investigate the factors affecting the therapeutic effects and complications fol owing surgery of posterior hip dislocation combined with femoral head fractures.
METHODS:Twenty-eight patients, who had been diagnosed as posterior hip dislocation combined with femoral head fractures in the 101 Hospital of Chinese PLA from September 2004 to May 2010, were enrol ed in this study. According to Pipkin typing, operative approach and the time from injury to surgery, therapeutic effects were evaluated using radiographs and the recovery conditions of hip function (Epstein method), and the occurrence of complications was recorded.
RESULTS AND CONCLUSION:A total of 28 patients were fol owed up from 1 to 5 years, averagely 2.8 years. Using the Epstein method, there were excellent in 6 cases, good in 12 cases, average in 7 cases, and poor in 3 cases, with an excellent and good rate of 64%. The therapeutic effects in patients with Pipkin I and II were good, with excellent and good rates of 100%and 78%, respectively. Moreover, the complications were less, with a rate of 17%and 22%, respectively. The therapeutic effects of patients with Pipkin III and IV were poor, especial y, Pipkin IV patients, whose excellent and good rate was only 20%and the incidence of complications was 80%. No significant difference in the incidence of complications was detected in patients undergoing Smith-Peterson anterior approach and K-L posterior approach (P>0.05). No significant difference in the incidence of complications was detectable among patients from three groups (the time from fracture to operation<12 hours, 12-48 hours, and>48 hours) (P>0.05). Results indicated that the choice of treatment method should be determined by the type of fracture. The prognosis depends on the patient’s age, time of treatment, types of fracture and dislocation, methods of treatment and related measures of prevention of complications.
6.Content Determination of Quercetin in Polygonum chinense L.from Different Growing Areas
Hua ZHU ; Ya GAO ; Kefeng ZHANG ; Xu ZHAO
Traditional Chinese Drug Research & Clinical Pharmacology 2000;0(06):-
Objective To determine quercetin content in Polygonum chinense L.from different growing areas.Methods RP-HPLC was used to determine quercetin content.Chromatographic conditions were as follows:chromatographic column of Agilent TC-C18 (4.6 mm?250 mm,5 ?m),mobile phase consisting of methanol-0.6 %phosphoric acid (52:48),with a velocity of 1 mL?min-1,column temperature at (25?1)℃,detection wavelength being 365 nm,elution time of 20min,and an injection volume of 20 ?L.Results Standard curve regression equation of quercetin is:Y=85 355X-48.16(r=0.999 3).A good linearity was showed in the range of 0.004~0.012 mg?mL-1,with average recovery being 100.3 %,and RSD of 1.44 %.The content of quercetin in the samples from different growing areas is in the range of 183.0~848.1 ?g?g-1.Conclusions The method is simple and reliable,and can be used to control the quality of Polygonum chinense L.The existence of some differences of quercetin content between medicinal materials from different growing areas indicates that we should make a quality standard to ensure the safety and effectiveness of Polygonum chinense L.in clinic.
7.Bipolar femoral head replacement for unstable femoral intertrochanteric fracture in elderly patients:hip joint function and complications
Zhangyong TAN ; Jianliang WANG ; Feng GUO ; Kefeng XU
Chinese Journal of Tissue Engineering Research 2015;(26):4118-4122
BACKGROUND:In elderly patients with unstable intertrochanteric fracture, because of poor general condition and poor bone condition, on one hand, the internal fixation of fracture may lead to nonunion. On the other hand, patients stil need longer time in bed and hip joint fixation, and may result in complications of long-term bed rest. Artificial femoral head replacement is a safe operation mode, can solve the problem of early ambulation of patients. OBJECTIVE:To observe the repair effect of bipolar artificial femoral head replacement on unstable femoral intertrochanteric fracture in elderly patients. METHODS: A total of 39 elderly patients with unstable femoral intertrochanteric fractures, who were treated in the Department of Orthopedics, 101 Hospital of Chinese PLA from 2005 to 2014, were enroled in this study. There were 21 males and 18 females, at the age of 80-96 years old, averagely 85 years old. They al received bipolar artificial femoral head replacement. Harris score was measured to assess hip joint function at 1 year after replacement. The incidence of complications was recorded. RESULTS AND CONCLUSION:A total of 39 cases were folowed up for 1-5 years. The wound of al patients was healed in the primary stage. No cardiovascular or cerebrovascular accident appeared. Al patients passed safely through the perioperative period. No severe complications occurred. Hip joint function was assessed according to Harris score at 1 year after replacement: excelent in 13 cases, good in 20 cases, average in 4 cases, poor in 2 cases, with an excelent and good rate of 85%. No dislocation appeared. The results suggest that bipolar artificial femoral head replacement can be used to treat femoral intertrochanteric fracture in elderly patients. The postoperative recovery time was short; bleeding was less; complications were few. Hip joint function recovered wel. For elderly patients with femoral intertrochanteric fracture, bipolar artificial femoral head replacement is an ideal safe effective repair method.
8.Research on relationship between expressions of apoptosis-related gene bcl-x and bax in hepatocellular carcinoma and its clinical pathological features
Hongyong XU ; Kaizong LI ; Youchi FU ; Kefeng DOU ; Jingmeng LI
Journal of Cellular and Molecular Immunology 2001;17(4):356-358
Aim To study relationship between expressions of apoptosis-related gene bax and bcl-x in heopatocellular carcinoma (HCC) tissues and its clinical feature. Mothods The expression of Bax and Bcl-x were determined by immunohistochemistry with EnvisionTM system. Results Bcl-x and Bax proteins were detectable in 20 and 19 out of 40 HCCs, respectively. Their expressions in HCC cells were lower than those in cirrhosis(P< 0.05), The expression of Bax and Bcl-x in highly or intermediatly differentiated HCC cells were highed than that in low-diffe-rehtiated HCC cells suggesting that there was significant relationship among bcl-x and bax expressions and differential degree, clinical stages of HCC cells, and AFP level. However, the expression of this proteins showed no relationship with patient's sex and age(> 60 or < 60 years old) (> 0.05). Conclusion Apoptosis-related genes bcl-x and bax participate partially in apoptotic regulation of HCC cells, and show that their expressions have correlation with differential degree, clinical stage of HCC cells and AFP levels.
9.Effects of Monocrotaline on Right Ventricular Function and Expression of Cardiac Canonical Transient Receptor Potential Channels Subfamily in Experimental Rats
Kefeng CAI ; Huiqin CHEN ; Xunfa XU ; Weiqiang LIN ; Chaoxiang XU ; Guozhen CHEN
Chinese Circulation Journal 2014;(11):928-931
Objective: To explore the effects of monocrotaline (MCT) on right ventricular function and expression of cardiac canonical transient receptor potential channels (TRPC) subfamily in experimental rats.
Methods: The SD male rats were randomly divided into 2 groups:Control group, the rats were normally fed and MCT group, the rats received a single dose injection of MCT 60 mg/kg to induce myocardial hypertrophy. n=10 in each group and all animals were treated for 3 weeks. The right ventricular hemodynamics parameters and right ventricular hypertrophy index (RVHI) were measured, right ventricular myocardium tissue section was observed by HE staining, the mRNA and protein expressions of TRPC subfamily were examined by RT-PCR and Western blot analysis.
Results: Compared with Control group, MCT group had increased RVSP, RVHI, RV+dp/dtmax and decreased RV-dp/dtmax, all P<0.01. In MCT group, the right ventricular myocardial cells had the thinker ifber, deeply stained nuclei with irregular shape. Compared with Control group, the mRNA and protein expressions of right ventricular TRPC6 were elevated in MCT group, n=6 and n=4 respectively, all P<0.05.
Conclusion:Right ventricular hypertrophy could be induced by 3 weeks MCT treatment, it up-regulating the mRNA and protein expressions of TRPC6 which might be involved in the occurrence and development of cardiac hypertrophy in experimental rats.
10.Application of factor analysis to evaluate deformation behaviors of frequently-used tablet excipients.
Xiaohai LI ; Meidai LI ; Yan DU ; Lijie ZHAO ; Yi FENG ; Desheng XU ; Kefeng RUAN
Acta Pharmaceutica Sinica 2013;48(9):1475-83
The present work is to investigate the correlation between physical properties and deformation behaviors of tablet excipients, and rank them according to their plastic performances during compaction. The excipients selected were compacted using Korsch XP1 after measuring their physical properties where the compression parameters for evaluating deformation behaviors were Heckle equation, compression work and elastic stretch in die. The correlations between compaction descriptors and physical parameters were analyzed by canonical correlation analysis, and factor analysis was simultaneously employed to synthetically assess deformation behaviors for all our samples. The canonical variables show that true density (Pa) correlated negatively with plastic coefficient (PL) and positively with yield pressure (YP); compression degree (Cp) correlated negatively with fast elastic stretch (FES) as well as YP and positively with PL. When factor scores were used in combination with original data, the plasticity of our samples was sorted and ranked as high (-0.56 < F' < 0.21), intermediate (-0.16 < F' < 0.36), or low (0.38 < F' < 0.84), which are in accord with plasticity rankings previously reported in literature. This study indicates factor analysis can be an approach to evaluate deformation behaviors of pharmaceutical powders.