1.Precise mechanical analysis on the femoral three-dimensional finite element model constructed based on DICOM data
Chinese Journal of Tissue Engineering Research 2013;(30):5483-5489
BACKGROUND:The finite element model has been developed from two-dimensional model to three-dimensional model, from linear model to nonlinear model. As the advantage of this method in the analysis of mechanical characteristics of the irregular objects, the finite element model has been widely used in the research of orthopedic biomechanics, especial y in the research of hip joint. OBJECTIVE:To analyze the stress state of human femur with finite element analysis method and to investigate a method that can rapidly construct femoral finite element model and precisely analyze the biomechanics. METHODS:Normal male femur was used as specimen for CT scan to obtain cross-sectional images of femur in each slice. Three-dimensional reconstruction was performed with DICOM data and MIMICS software, then the femoral three-dimensional finite element model was established with the finite element analysis ABQUS 6.8 software, and the stress distribution of the model was analyzed under loading condition. RESULTS AND CONCLUSION:Based on DICOM data, three-dimensional finite element model of femur was constructed more quickly and precisely. The models were divided into 38 636 nodes and 201 422 units. The model included the parts of cortical and cancel ous bone. The biomechanical test results were accorded with the previous results, so the model could objectively reflect the real femur shape and biomechanical behavior with high precision. The Mimics software provided a simpler and effective method for the construction of femur model and improved the efficiency of modeling, and the three-dimensional finite element model based on DICOM data was accurate in shape and can be used for the normal research on biomechanical behavior of femur. The stress distribution analyzed with ABQUS 6.8 software is consistent with the clinical observation.
2.Research advances in tooth agenesis[WT5”BZ]
Hailang FENG ; Xiaoxia ZHANG ; Hua WU
Journal of Peking University(Health Sciences) 2004;0(01):-
Tooth agenesis constitutes one of the most common developmental anomalies in man. Oligodontia is defined as congenital absence of six or more teeth. Based on the studies of our team in cooperation with Peking University Center for Human Disease Genomics in the past five years, this article reviews the current research progress in clinical phenotypes and case collection, epidemiological investigation and etiological genetic studies of oligodontia. The symptoms of oligodontia were classified into syndromic and non-syndromic according to the occurrence of tooth agenesis with or without systemic developmental defects. As for the advancement of theories and techniques of molecular genetics, a number of gene mutations have been identified to be the direct etiological factors causing some specified diseases, especially those with developmental defects. Here, this article summarized the outcomes of molecular genetic study of some cases we collected. Of the systemic oligondontia patients, a new four-base-deletion mutation in PITX2 was identified in a large kindred with typical symptoms of Rieger Syndrome; four different gene mutations in ED1 casing X-linked hypohidrotic ectodermal displasia were found in five nucleus families. Compared with the former, non-syndromic oligodontia has more genetic heterogeneity rather than some specific virulence gene. PAX9 and MSX1 are the identified genes associated with family tooth agenesis without systemic syndrome. Also, in our research, three gene mutations in CBFA1 were detected in four cleidocranial dysplasia families, which is a systemic developmental disease including the symptoms of tooth eruption abnormality and accessory teeth.
3.Granger causality analysis methods on brain functional signals
Weina LI ; Xiaolin ZHENG ; Wensheng HOU ; Guocai WU ; Hua FENG
International Journal of Biomedical Engineering 2011;34(6):375-379
How does brain select and adjust the distributed neural activities to achieve its function? To address this problem,researchers introduce Granger causality analysis method to brain functional study,which deals with the estimation of causal influences among multi-variables.First,basic principles of Granger Causality and its improved algorithm structural vector autoregression (SVAR) are introduced.Then several technical problems are reviewed which should be noted when analyzing brain functional signals by Granger Causality Methods.In the end,the application foreground of Granger Causality in epilepsy localization is introduced by taking idiopathic generalized epilepsy as the example.
5.Management of Parkinson's Diseases with Microelectrode-guided Stereotactic Pallidotomy and Thalamotomy
Gaoyu CUI ; Hua FENG ; Xianrong WANG ; Guocai WU ; Zhi CHEN
Chinese Journal of Tissue Engineering Research 2001;5(10):154-155
Objective To study the methods and outcome of 71 patients with Parkinson's disease treated with microelectrode-guided stereotactic pallidotomy and thalamotomy. Method Pallidal and thalamal target sites are chosen by supervision of microelectrode recording technique in 71 patients with Parkinson's disease. The UPDRS motor score was used to evaluate the outcomes 12 weeks before and after operation Result After 12 months follow-up, tremor disappeared completely or nearly completely in 12 patients who underwent unilateral and l bilateral ventrolateral thalamotomy. Dramatic improvement of tremor, rigidity, bradykinesia were observed in 57 patients underwent posteroventral pallidotomy,including 6 underwent bilateral posteroventral pallidotomy. Intracerebral hemorrhage was observed in l patient. Conclusion Microelectrode-guided stereotactic pallidotomy and thalamotomy are effective in treatmenting Parkinson's disease, but with serious complications
6.Analysis of Klebsiella pneumoniae infection in 75 preterm infants
Shaodong HUA ; Qiuping LI ; Jieting HUANG ; Zhixin WU ; Zhichun FENG
Chinese Journal of Perinatal Medicine 2012;15(2):95-100
Objective To analyze the clinical characteristics of Klebsiella pneumoniae infection in preterm infants. Methods Clinical data of 75 preterm infants infected with Klebsiella pneumoniae treated in BaYi Children's Hospital from February 6,2008 to February 10,2010 were retrospectively analyzed.The difference of auxiliary examination between early-onset and late-onset infection group were compared by two independent samples t test.Spearman correlation analysis and non-conditional Logistic regression analysis were used to analyze the high risk factors and the prognostic factors of Klebsiella pneumoniae infection in preterm infants. Results The incidence of Klebsiella pneumoniae infection was 2.8% (75/2721) in preterm infants,and the mortality rate was 9.3% (7/75). There were 71 cases of Klebsiella pneumoniae sepsis and 4 cases of Klebsiella pneumoniae pneumonia.Among 75 cases,63 cases were early-onset infection (onset age≤72 h) and 12 were late-onset infection (onset age>72 h).All patients presented with poor response,heart rate during quiet sleep > 160/min and low oxygen saturation.The mean corpuscular volume and mean corpuscular hemoglobin concentration in early-onset Klebsiella pneunoniae infection cases were higher than those in late-onset neonates [(128.87±24.60) fl vs (113.72±13.54) fl,t=-2.07,P<0.05and (38.11±2.15) pg vs (36.98±1.05) pg,t=-2.76,P<0.05].Low birth weight and caesarean section were associated with early-onset Klebsiella pneumoniae sepsis (r=0.250 and -0.240,P<0.05). The prognosis of Klebsiella pneumoniae infection was associated with hospital stay and duration of premature rupture of membranes (r=0.368 and 0.318,P<0.05). Conclusions There were no specific clinical manifestations for Klebsiella pneumoniae infection in preterm infants.Preterm infants with low birth weight,long duration of premature rupture of membranes,delivered by caesarean section and received invasive operation are likely to develop Klebsiella pneumoniae infection.
7.Effect of dehydroepiandrosterone on experimental osteoarthritis in rabbits
Hua-Chen YU ; Li-Dong WU ; Yan XIONG ; Jie FENG ;
Chinese Journal of Rheumatology 2003;0(09):-
Objective To observe the effect of intra-articular injection of dehydroepiandrosterone (DHEA)on the experimental osteoarthritis in rabbits and study the mechanism.Methods Forty rabbits un derwent unilateral anterior cruciate ligament transection(ACLT)and then divided into two groups randomly. 100?mol/L DHEA resolved in the dimethylsulphoxide were injected into the knees of experimental rabbits 4 weeks after transection,once a week for five weeks.Rabbits in the control group were treated under the same schedule using dimethylsulphoxide.All rabbits were killed 9 weeks after ACLT and the knee joints were evalu- ated by gross morphology and histology.The mRNA expression of metalloproteinases-3(MMP-3),tissue in- hibitor of metalloproteinases-1(TIMP-1)and interleukin-lbeta(IL-1?)in the cartilage and synovium was analyzed using reverse transcription polymerase chain reaction(RT-PCR).Results Gross morphologic in- spection and histological evaluation showed that the extent and grade of cartilage and synovium damage in the experimental group were less severe than the control group.The mRNA expression of MMP-3 in cartilage and synovium decreased significantly in the experimental group(both P<0.05).The mRNA expression of TIMP-1 in cartilage and synovium increased significantly in the experimental group compared with that in the control group(both P<0.05).No significant difference of IL-1?mRNA expression in cartilage was found between the experimental and the control groups(P>0.05).The mRNA expression of IL-1?in the synovium was signifi- cantly suppressed in the experimental group compared with that in the control group(P<0.01).Conclusion DHEA protects against cartilage degradation,alleviates synovium inflammation and inhibits the progression of osteoarthritis in the experimental model.Down-regulation of MMP-3 and up-regulation of TIMP-1 in cartilage and synovium and IL-1?in the synovium may be the mechanism of the protective effect of DHEA on os- teoarthritis.
8.Endovascular embolization treatment of intracranial aneurysms with Gugliemi detachable coils
Gang ZHU ; Nan WU ; Hua FENG ; Xianrong WANG ;
Journal of Third Military Medical University 1983;0(04):-
Objective To report the experiences in the endovascular embolization treatment of intracranial aneurysm. Methods A total of 29 patients with intracranial aneurism were treated with Gugliemi detachable coils(GDC). Results Complete occlusion was found in 15 cases, 90% occlusion in 12 and 80% in 2. Three patients had different degrees of headache. The coil escaping from the sac of the aneurysm and suspending in the parent artery of the aneurysm was seen in 1 patient. Two patients died: one was due to disruption of aneurysm and another severe bleeding in digestive tube. Conclusion Endovascular embolization of intracranial aneurysm is a minimally traumatic, safe and effective method for the treatment of intracranial aneurysm. GDC system is of easy operation, high safety and low incidence of complications.
9.Comparison of different genesis of olfactory ensheathing cell transplantation for intracerebral hemorrhage
Weijiang WU ; Hua LU ; Feng GE ; Jie XU ; Aihua ZHU
Chinese Journal of Tissue Engineering Research 2007;0(06):-
0.05). CONCLUSION: There are no significant differences in cell characteristics and transplantation outcome using OB-OEC and OM-OEC transplantation for repairing neurological function.
10.Effect of Xingnaojing injection on intestinal mucosal barrier in septicemia and intracerebral hemorrhage mice
Wen-Qian WANG ; Shuang WU ; Feng-Hua FU
Chinese Journal of Pharmacology and Toxicology 2018;32(4):307-307
OBJECTIVE Xingnaojing injection(XNJ)is an extracts of Angong Niuhuang Pill that is a well-known traditional Chinese medicine used for the treatment of septicemia and stroke.This study aims to investigate the effect of XNJ on intestinal mucosal barrier in septicemia and intracerebral hem-orrhage(ICH)mice models.METHODS The septicemia mice models were induced by intravenous in-jection with lipopolysaccharide(20 mg·kg-1).And the ICH mice models were made by intrastriatal injec-tion of bacterial collagenase. The septicemia animals were treated intravenously with XNJ at dose of 2.5,5,10,or 15 mL·kg-1.The ICH animals were treated intravenously with XNJ at dose of 10 mL·kg-1. Thereafter, the permeability of intestinal mucosa was assayed by FITC-D method. RESULTS Com-pared with the control group(44.72±4.30),the permeability of intestinal mucosa in the mice in septice-mia group (233.68±28.18) was significantly increased (P<0.01). Treatment with XNJ at dose of 5, 10, and 15 mL·kg-1reduced the permeability of intestinal mucosa (150.45 ± 17.52,139.21 ± 17.05,132.55 ± 18.88,respectively, P<0.01)except 2.5mL·kg-1(240.71±21.42,P>0.01);Compared with sham group (57.88±7.31),the permeability of intestinal mucosa in the mice of ICH(282.25±23.78)was significantly in-creased(P<0.01). Treatment with XNJ (10 mL·kg-1)in the mice of ICH group ameliorated the change of permeability in intestinal mucosa (148.83±15.86, P<0.01). CONCLUSION XNJ exhibits the protec-tive effect on the intestinal mucosal barrier in septicemia and ICH, which will prevent the endotoxin to penetrate the intestinal mucosa and then to enter the circulation in infections and stress.