1.Single iliac screw and dual iliac screws and titanium mesh cage fixation in the reconstruction of lumbosacral defects with finite element analysis
Liang MA ; Weichun GUO ; Yongtao XU
Chinese Journal of Tissue Engineering Research 2016;20(39):5859-5866
BACKGROUND:The surgical management to reconstruct the stability in lumbosacral region is very chal enging. There are many techniques to reconstruct the stability of the lumbosacral region, but the internal fixation loosening, fracture and pseudoarthosis are not uncommon. OBJECTIVE:Finite element analysis was used to analyze the stability of two types of reconstruction procedures and the stress of the internal fixation system. METHODS:A 64-slice spiral CT scan was used in a subject from L1 to pelvis. The scan data were imported into the Mimics 15.0 software to generate a three-dimensional surface model. The three-dimensional solid model was established using in the SolidWorks software. The solid geometry model of the L3, 4 pedicle screws combined with single iliac screw fixation and L3,4 pedicle screws combined with dual iliac screws and anterior titanium mesh cage support fixation were constructed by the Solidworks software. Two kinds of reconstruction procedures were simulated. The models were given material properties and analyzed by using the ABAQUS software. RESULTS AND CONCLUSION:(1) The maximum stress was 195.3 MPa in the complete model, 189.5 MPa in single iliac screw model, and 149.2 MPa in dual iliac screw+titanium cage model when constrained the roof of double acetabulum and applied a vertical load of 1 000 N. (2) The axial compression rigidity was 551.572 N/mm in the complete model, 613.87 N/mm in the single iliac screw model and 1 683.50 N/mm in the dual iliac screw+titanium cage model. (3) The bending rigidity of the dual iliac screw+titanium cage model was bigger than other models at 6 directions when applied 7 N?m bending loads. The maximum stress of single iliac screw model was bigger than other models. (4) The results suggest that the dual iliac screw+titanium mesh cage reconstruction can effectively restore the stability of the lumbosacral area. The stress of internal fixation system is smal er and more dispersed. There is obvious stress concentration in the connecting rod and the tail of the single iliac screw. The single iliac screw internal fixation system is easy to fatigue fracture and loosening.
2.Analysis on cats' death factors after craniocerebral missile wound under different temperature and humidity
Dexuan MA ; Yanwu GUO ; Ruxiang XU
Chinese Journal of Trauma 1990;0(03):-
ObjectiveTo investigate the changing behavior of cats' vital signs and death factors after craniocerebral missile wound in the environme nt of high temperature and humidity. MethodsA total of 32 hy brid cats were randomly divided into four groups and respectively put into the f ollowing environments after wound, ie, Group A at 25℃ with relative humidity (R H) of 50%, Group B at 35℃ with RH 85%, Group C at 38℃ with RH 90% and Group D at 40℃ with RH 95%. Then, blood pressure, pulse, respiratory frequency and body temperature were recorded every 10 minutes for six hours. Results The vital signs of normal gunshot wound group during the experiment were stable, while body temperature, respiratory frequency and heart rate of cats in each group were significantly different at the same time point with the increa se of temperature and humidity ( P
3.A Study on the Relationship Between the Abnormal Expression of TGF-?_1, TGF-?RⅠand Malignant Biological Behaviors in Ovarian Carcinoma
Yuzhen GUO ; Hua XU ; Wei MA
Journal of Chinese Physician 2001;0(02):-
Objective To investigate the expression and significance of transforming growth factor-beta1(TGF-? 1),transforming growth factor-beta receptor typeⅠ(TGF-? RⅠ) in human ovarian carcinoma. Methods Inmmunohistochemical SP method was used to detect the expression of TGF-? 1 and TGF-? RI in 85 cases of benign and malignant ovarian tumors. Results The positive rate of TGF-? 1 in benign and malignant ovarian tumors was significantly higher than that in the normal ovarian tissues(P
4.Analysis of polysaccharide composition of Hedyotis difusa Willd polysaccarides by pre-column derivatization HPLC
Ludan BAO ; Guofang XU ; Zheng MA ; Na GUO ; Xingjie GUO
Chinese Traditional Patent Medicine 1992;0(03):-
AIM:The polysaccharides of Hedyotis difusa Willd of different sources were extracted and its content and composition of the polysaccharide was analyzed. METHODS: The microwave was employed for the aqueous extract of Hedyotis difusa Willd and the content of total sugar was determined by phenol-sulfur test,the monosaccharides composition was determined by HPLC with pre-column derivatization. RESULTS: The polysaccharide obtained from the samples of Guangdong Province had the highest content.The analytic data showed that the composition of monosaccharides in hydrolytic polysaccharides of Hedyotis difusa Willd were mannose,glucose,galactose,arabinose and rhamnose,the average content of polysaccharides was 9.82%. CONCLUSION: The HPLC method with pre-column derivatization is appropriate for the analysis of monosaccharide composition of Hedyotis difusa Willd polysaccharides and the method is simple,quick and accurate.
6.The protection effect of cysteine rich-protein 61 on renal tubular epithelial cells against apoptosis induced by hypoxia
Yan XU ; Min GUO ; Hui DONG ; Xuemei LIU ; Ruixia MA
Chinese Journal of Nephrology 2015;31(6):451-455
Objective To observe the expression of cysteine rich-protein 61 (Cyr61) on renal tubular cells,to explore its effects against hypoxic induced kidney injury and the underlying mechanisms.Methods A stably Cyr61 expressed tubular cell line Cyr61-HK2 was established based on HK2 cells and recombinant Cyr61-lentivirus.BrdU incorporation assay was used for cell proliferation.The apoptosis of cells was analyzed by flow cytometry with Annexin V and propidiumiodide staining.Western bloting was used to detect the protein expression of BAD,Akt and ERK.Results (1) Cyr61-HK2 cells displayed more proliferation ability than HK2 cells.(2) Under hypoxia condition,the apoptosis of both HK2 and Cyr61-HK2 cells increased,but the apoptosis of Cyr61-HK2 cells was lesser than HK2 cells.(3) The expression of Cyr61 led to the phosphorylation of BAD,Akt and ERK on 0 h,0.5 h,1 h (all P < 0.05).Conclusion The expression of Cyr61 can promote cell proliferation and dampen cell apoptosis induced by hypoxia,which may be involved in the Akt/ERK signal pathway.
7.Late lumen loss of drug eluting stents versus bare mental stents for saphenous vein graft intervention
Jincheng GUO ; Min XU ; Guozhong WANG ; Changsheng MA
Chinese Journal of Tissue Engineering Research 2008;12(35):6971-6975
BACKGROUND:Drug eluting stents(DESs)has been applied in treatment of saphenous vein grafts,but few reports are present.OBJECTIVE:To retrospectively compare the late loss and major adverse cardiac events(MACE)between DES and bare mental stents(BMS)in patients with diseased saphenous vein grafts.DESIGN,TIME AND SETTING:The experiment,a grouping control study and follow-up observation,was performed from January 2002 to February 2007 in Beijing Luhe Hospitat and Beijing Anzhen Hospital.PARTICIPANTS:Ninety-seven consecutive patients with saphenous vein graft lesions were treated with DESs (DESgroup.n=50)or BMSs(BMS group,n=47).METHODS:All patients underwent percutaneous coronary implantation and received clinical follow-ups immediately.They were scheduled to undergo 12-month coronary angiography.MAIN OUTCOME MEASURES:The cardiac events including death,myocardial infarction,target lesion and/or target vessel revascularization.Late lumen loss was recorded and compared between the two groups.RESULTS:There were no significant differences on the gender,age,history of bridge vessels and complication between the two groups(P>0.05).A total of 97 patients with 118 lesions localized in 105 diseased saphenous vein grafts were included:50 patients received 71 DESs for 59 lesions,whereas 47 patients received 62 BMSs for 59 lesions.Procedural success was achieved in 94.0%of patients in the DES group and 93.6%in BMS group(P=0.43).At 12 months,the cumulative incidence of MACE was significantly lower in DES group than in BMS group(1 2.0%vs.29.8%.P=0.03).Angiographic follow-up was available for 54 patients,26 patients in DES group and 28 in BMS group.Late lumen loss was significantly reduced in DES group[(0.32±0.65)mm vs.(0.79±1.23)mm,P=0.01].The DES group had a significantly lower incidence of target lesion revascularization compared with BMS group(6.0%vs.19.1%.P=0.05).By Cox regression analysis,independent predictors for MACE at 12-month follow-ups were diabetes (OR:2.37;CI:0.95 to 5.88;P=0.064),BMS(OR:2.86;CI:0.98 to 8.34;P=0.05),and stent per lesion(OR:2.92;CI:1.25 to 6.82;P=0.01).CONCLUSION:DES is superior to BMS in diseased saphenous vein grafts,and it can significantly reduce late lumen loss and MACE.
8.SoloMo concept-based strategies for the service in medical college and university libraries
Yujia SUN ; Ma SUO ; Hui XU ; Yan GUO
Chinese Journal of Medical Library and Information Science 2016;25(9):55-58
With the arrival of SoloMo era and the change of users need, the passive service has changed to active service in libraries in order to increase the use of their resources. After the SoloMo concept was described, the bar-riers in users of medical libraries were investigated with questionnaires, the strategies for SoloMo innovative service and change of traditional service patterns in medical libraries were elaborated in order to provide personal service for the users at anytime and anywhere.
9.A survey of the situation of medical students’English works reading
Xu MA ; Liping GUO ; Ying NIU ; Zhilan HU
Chinese Journal of Medical Education Research 2006;0(08):-
A survey was conducted to investigate the situation of English works reading activities among medical students and their attitude to the medical contents in English works.The result showed that medical students support the setting-up of literature and medicine course and it was believed that medicine in literature would be helpful to improve the quality of medical humanity education.
10.Video-assisted thoracoscopic surgery and conventional radical operation on stage Ⅰ , Ⅱ esophageal cancer
Baochuan XU ; Meiqing XU ; Dazhong WEI ; Dongchun MA ; Mingfa GUO ; Baolin RONG ; Xinyu MEI ; Shibin XU
Chinese Journal of Postgraduates of Medicine 2010;33(14):13-15
Objective To compare the results and safety between video-assisted thoracoscopic surgery ( VATS ) and conventional radical operation in patients with stage Ⅰ , Ⅱ esophageal cancer. Methods Retrospectively reviewed 43 patients with stage Ⅰ , Ⅱ esophageal cancer,underwent either VATS radical operation (VATS group,16 cases) or conventional radical operation (control group,27 cases ) from September 2007 to September 2009. Patient's operative characteristics and postoperative courses were compared between two groups. Results In VATS group the operation time was ( 115.6 ± 48.0) min,the peri-operative blood loss was ( 131 ± 71 ) ml,the first postoperative day chest lead quantity was (331 ± 170)ml, the time of postoperative chest tube was (7.25 ± 2.35) d,the postoperative 36 h visual analogue scale (VAS) was (3.4 ± 1.2) scores,the postoperative drainage of chest was ( 1281 ± 534) ml,the 72 h postoperative locomotor activity of right upper extremity was (5.1 ± 1.5) cm. While in control group was ( 145.6 ± 20.6)min, (292 ± 111 ) ml, (494 ± 194) ml, ( 10.00 ± 2.79 )d, (7.3 ± 1.4) scores, ( 1780 ± 731 ) ml, ( 15.6 ± 3.1 )cm respectively (P < 0.01 or < 0.05 ). The lymph node dissection number,the total cost of hospital between were no statistically significant differences in two groups (P >0.05). Conclusion Comparing with conventional radical operation, VATS radical operation for patients with stage Ⅰ , Ⅱ esophageal cancer appears to be as effective but less morbid.