2.Carbon fiber-reinforced polyetgeretherketone for femoral head prosthesis and its stability:a biomechanical analysis
Zhihua JI ; Bingshen JIA ; Liyi ZHOU ; Kun FU ; Zhibin MENG ; Peng YU ; Dake YUN
Chinese Journal of Tissue Engineering Research 2017;21(15):2325-2330
BACKGROUND: Metal implants have been extensively applied in joint arthoplasty, but the stress shielding effect caused by its high elastic modulus results in a series of complications, such as bone resorption, bone atrophy and prosthesis loosening. Carbon fiber-reinforced polyetheretherketone (CF-PEEK) composites are anisotropic and exhibit more advantages used for prosthesis due to its low elastic modulus and high intensity.OBJECTIVE: To investigate the blood compatibility of CF-PEEK composites, and compare the biomechanical properties after arthroplasty between CF-PEEK composites and Co-Cr-Mo used for femoral head prosthesis. METHODS: (1) The blood compatibility of CF-PEEK composites was evaluated through hemolysis test. (2) Femoral samples from eight fresh cadavers were collected and randomly divided into two groups, followed by subjected to CF-PEEK and Co-Cr-Mo prosthesis replacement, respectively. The displacement between the prosthesis and bone was measured under loading 200, 400, 600, 800 and 1000 N, and the torsional strength after arthroplasty was detected.RESULTS AND CONCLUSION: (1) The hemolysis rate of the CF-PEEK composites was 3.23% < 5%, which was in line with the national standards for biological evaluation of medical devices. (2) The micromovement in distal prosthesis was significantly less than that of proximal prosthesis under different loads in both two groups (P < 0.05). (3) The torsion angle under different loads in the CF-PEEK group was significantly less than that in the Co-Cr-Mo group (P < 0.05), and the torsion stiffness in the CF-PEEK group was significantly higher than that in the Co-Cr-Mo group (P < 0.05). (4) To conclude,the CF-PEEK composites possess good blood compatibility and stability, which can be used as a prosthesis material.
4.Influence of bicortical anchorage on the natural frequencies of dental implant.
Kun WANG ; De-hua LI ; Ji-xiang ZHOU ; Cong-ji ZHANG ; Bao-lin LIU ; Yu-long LI
West China Journal of Stomatology 2006;24(1):86-88
OBJECTIVETo investigate the influences of bicortical anchorage on values of natural frequencies of dental implants utilizing the 3-dimensional finite element analysis.
METHODSUsing the commercial code of Solidworks, 3-D models of a screw-shaped dental implant and a mandibular bone segment were generated. After the 3-D implant-bone complex was meshed by ABAQUS software, effects of bicortical anchorage on the buccolingual and axial first-order natural frequencies of the implant were computed.
RESULTSBicortical anchorage increased both the buccolingual and axial natural frequencies remarkably. As the bicortical anchorage got deeper, the frequencies correspondingly got higher.
CONCLUSIONBicortical anchorage can increase the buccolingual and axial primary stability of dental implants.
Dental Implantation, Endosseous ; Dental Implants ; Dental Stress Analysis ; Finite Element Analysis ; Humans ; Mandible
5."Clinical Experience for ""One-stop"" Performance of Thoracic Endovascular Aortic Repair and Coronary Artery Bypass Grafting"
Mingyao LUO ; Qian CHANG ; Cuntao YU ; Xiaogang SUN ; Xiangyang QIAN ; Lei CHEN ; Bingyang JI ; Haitao ZHANG ; Kun FANG ; Zhou ZHOU ; Chang SHU
Chinese Circulation Journal 2017;32(6):556-559
Objective: To explore the safety and strategy of thoracic endovascular aortic repair (TEVAR) combining coronary artery bypass grafting (CABG) as one-stop performance in treating the patients with coronary artery disease (CAD) and thoracic aorta disease. Methods: A total of 20 patients received one-stop treatment of TEVAR combining CABG in our hospital from 2009-04 to 2016-01 were retrospectively analyzed. There were 18 male and the mean age of patients was (65.2±8.5, 51-82) years. The performance strategy and peri-operative management were studied. Results: There were 1/20 patient received 2 stents implantation in thoracic aorta and 19 received 1 stent in thoracic aorta those including 1 case with endovascular repair of abdominal aortic aneurysm, 1 with right iliac artery stent implantation and 1 with carotid endarterectomy at meanwhile. The average number of coronary artery bypass branch was (2.4±0.94, 1-4) and 10 (50%) patients received internal mammary artery grafting. The average in-hospital time in all 20 patients was (22.4±11.6, 8-58) days. There were 6 (30%) patients received blood transfusion; 1 (5%) having low cardiac output syndrome received extracorporeal membrane oxygenation (ECMO), then received the second thoracotomy for hemostasis due to excessive pleural effusion; 2 (10%) patients died at 30 days post-operation. 1 patient lost contact and 17 received clinical or telephone follow-up visit at the average of (13.4+13.6, 1-49) months; 2 patients died for cerebral hemorrhage at 12 and 49 months post-operation, the rest 15 had disappeared symptoms and improved quality of life, no operation related death occurred. Conclusion: TEVAR combining CABG as one-stop performance presented good mid-term effect in treating the patients with CAD and thoracic aorta disease; in otherwise, the operative time and risk might be increased by two step performance.
6.In vivo study of remineralization with trace elements by laser scanning confocal microscope.
Xue-dong ZHOU ; Hong-kun WU ; An-chun MO ; Hong TAN ; Ji-yao LI
Chinese Journal of Stomatology 2003;38(1):59-62
OBJECTIVETo evaluate in vivo the remineralization containing trace elements.
METHODSThe volunteers were selected by pre-designed criteria of adopting and eliminating. Caries-like lesions were prepared in the enamel of extracted human premolars with the use of demineralizing solution. Sections of the normal and lesion enamel (approximately 2 mm x 2 mm) were prepared, with the cut surfaces protected by nail varnish. 2 enamel specimens were mounted in a removable appliance. By measuring lesion parameters (area, total and average dye fluorescence) on a tooth with confocal laser scanning microscopy (CLSM), the effect of remineralization was assessed. Specimens were cut and stained with a fluorescent dye (0.1 mmol/L rhodamine B) for 1 h and analyzed using CLSM.
RESULTSCLSM detected significantly greater remineralization (P < 0.05) in the specimens treated with the trace elements fluoride-containing solution and only containing fluoride (P < 0.05), especially more obvious difference was shown upon remineralized solution with trace elements, which means it produced a greater remineralization. CLSM data of remineralized solution with trace elements were showed: delta Z vs. Area = -50.4 +/- 8.1; delta Z vs. TF = -27.8 +/- 3.8; delta Z vs. AF = -91.5 +/- 8.9.
CONCLUSIONSThe ability of remineralization of the new solution is better than that only containing fluoride in in vivo study. It can potentially prevent initiation of caries. This study provides not only the theoretical foundation for clinical application, but also shows a new kind of experimental method in the study of demineralization and remineralization.
Dental Caries ; drug therapy ; metabolism ; Dental Enamel ; drug effects ; metabolism ; Fluorides ; pharmacology ; Humans ; Microscopy, Confocal ; Tooth Remineralization ; methods ; Trace Elements ; pharmacology
7.Treating Neer two- and three-part of proximal humeral fractures through anterolateral acromial approach and deltopectoral approach.
Qi-ming CHEN ; Lie-feng JI ; Zhi-jun PAN ; Xiao-jun ZHOU ; Jiang ZHU ; Zhe-biao CAO ; Ding XU ; Ju-kun CHEN
China Journal of Orthopaedics and Traumatology 2014;27(12):991-994
OBJECTIVETo compare clinical results of treating Neer two- and three-part of proximal humeral fractures between anterolateral acromial approach and deltopectoral approach.
METHODSFrom January 2009 to December 2012, 49 patients with Neer two- and three-part of proximal humeral fractures were treated with locked plate fixation. In anterolateral acromial approach group, there were 22 patients including 9 males and 13 females with an average of (63.2±7.6) years old, while 27 patients in deltopectoral approach including 12 males and 15 females with an average of (62.9±7.0) years old. Operative time, blood loss during operation, fracture healing time and complications were observed and compared, postoperative Constant-Murley scoring and VAS scoring were applied for evaluate function of shoulder joint and pain at 3 months, 1 and 2 years respectively.
RESULTSAll patients were followed up from 24 to 41 months with an average of 34.5 months. Operative time, blood loss, fracture healing time in anterolateral acromial approach group was (68.20±7.04) min, (151.30±20.57) ml, (10.88±4.90) weeks respectively, and better than that of in deltopectoral approach group which was (75.81±13.70) min, (242.10±37.25) ml and (13.60±2.45) weeks. Three months after operation, Constant-Murley scoring and VAS score in anterolateral acromial approach group was 88.32±5.45, 0.41±0.63 and better that of in deltopectoral approach group which was 63.53±8.31, 1.65±1.02. There was no significant differences between two groups in Constant-Murley scoring and VAS score at 1 and 2 years after operation. Each group has one case occurred loss of length humerus head height, and there was 1 case with subacromial impingement, 1 case with bolt loose and 2 cases with delayed union in deltopectoral approach. No axillary nerve injury, humeral head necrosis and breakage of internal fixation occurred both of two groups.
CONCLUSIONBoth of anterolateral acromial approach and deltopectoral approach are effective in treating Neer two- and three-part of proximal humeral fractures, and can obtain excellent outcomes. Moreover, anterolateral acromial approach has advantage of less trauma, less blood loss, shorter operative time, rapid recovery of shoulder joint function and fracture.
Aged ; Case-Control Studies ; Female ; Fracture Fixation, Internal ; methods ; Fracture Healing ; Humans ; Male ; Middle Aged ; Recovery of Function ; Shoulder Fractures ; physiopathology ; surgery
8.Protective effect of non-mitogenic haFGF on retinal injury induced by N-methyl-N-nitrosourea in Sprague-Dawley rats.
Hua XU ; Jin-nan YANG ; Qing ZHENG ; Cheng-can YAO ; Yan-ping WANG ; Ji-zhou XIANG ; Xiao-kun LI
Acta Pharmaceutica Sinica 2005;40(4):306-310
AIMTo study the effect of non-mitogenic human acidic fibroblast growth factor (nm-haFGF) on retinal injury induced by N-methyl-N-nitrosourea (MNU) in Sprague-Dawley rats and its mechanism.
METHODSFemale rats of 50-days-old were injected with MNU (60 mg x kg(-1)) intraperitoneally, and three doses of nm-haFGF (1.25 microg, 2.5 microg and 5 microg in one eye of each rat) were injected, separately, into vitreous body of one eye of each rat twice a day at 0 and 12 h after MNU treatment. 24 h later, apoptotic index of photoreceptor cells was detected by TUNEL labeling and the expressions of Bcl-2 and Bax were analyzed by Western blotting. At the 7th day, retinal injury was evaluated based on retinal thickness.
RESULTSCompared with model group, apoptotic index of photoreceptor cells was significantly reduced in nm-haFGF groups at the dose of 1.25 microg and 2.5 microg in one eye of each rat at 24 h, and the total retinal thickness as well as the outer retinal thickness markedly increased 7 days after MNU, respectively. The expressions of Bcl-2 increased and that of Bax decreased adversely after being injected with different doses of nm-haFGF.
CONCLUSIONnm-haFGF partially suppressed retinal injury induced by MNU in Sprague-Dawley rats. The mechanism could be related to up-regulation of Bcl-2 and down-regulation of Bax.
Animals ; Apoptosis ; drug effects ; Female ; Fibroblast Growth Factor 1 ; genetics ; pharmacology ; Methylnitrosourea ; Photoreceptor Cells, Vertebrate ; drug effects ; pathology ; Protective Agents ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Retina ; drug effects ; pathology ; Retinitis Pigmentosa ; chemically induced ; metabolism ; pathology ; bcl-2-Associated X Protein ; metabolism
10.Investigating genotype of HCV distribution among residents in a "blood donation" village in Hebei Province.
Chang-Hong HUANG ; Ji-Kun ZHOU ; Li LIU ; Rong-Men JIANG ; Yan-Qiang CAO ; Zhen-Yun MU ; Yong ZHANG
Chinese Journal of Experimental and Clinical Virology 2009;23(1):8-10
OBJECTIVETo investigate genotype of HCV infection among residents in a rural village, Hebei Province.
METHODSBlood samples of the 520 residents were collected, and C/E1 of HCV genome of the 483 samples were obtained by RT-PCR amplifying, and the gene sequences were analyzed and the polygenetic tree were drawn by the software Mega 4.0.
RESULTSIn 483 subjects, HCV-RNA positive objectives are 70, positive prevalence is 14.5%, genotyping for all the samples successfully, including genotypes 1b and 2a, which are 36 (51.4%), 34 (48.6%) respectively.
CONCLUSIONHCV RNA positive rate is 14.5%, which is higher than general people. Subtypes 1b and 2a seemed to be the dominant genotypes of HCV in Zhao county area of Hebei Province.
Adolescent ; Adult ; Blood Donors ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Genotype ; Hepacivirus ; classification ; genetics ; isolation & purification ; Hepatitis C ; epidemiology ; virology ; Humans ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Molecular Sequence Data ; Phylogeny ; Young Adult