1.Application of rapid prototype and 3D printing in therapy of complex pilon fractures
Chinese Journal of Orthopaedic Trauma 2016;18(1):42-46
Objective To investigate the value of 3D rapid prototype technology in therapy of complex pilon fractures.Methods In this study,60 patients with pilon fracture who had been hospitalized during January 2013 to May 2014 were randomly and equally divided into a 3D group and a control group according to their hospitalization order.The 3D group:21 males and 9 females,an average age of 34.8 ±6.0 years,13 cases of AO type C2 and 17 ones of AO type C3.The control group:21 males and 9 females,an average age of 35.8 ±6.2 years,12 cases of AO type C2 and 18 ones of AO type C3.The 3D group received surgery aided by rapid prototype and 3D printing while the control group underwent conventional surgery with open reduction and internal fixation.In the 3D group,the distal tibia models were manufactured by 3D rapid prototyping technology based on the 3D reconstructions which were accomplished by computer aided technology.The diagnosis,classification and preoperative plan were then conducted using the models.The 2 groups were compared in terms of operation time,postoperative skin necrosis and infection,and Maryland foot function scoring at the last follow-up.The 2 groups were compatible in preoperative demographic data (P > 0.05).Results There were significant differences between the 3D and control groups in operation time (65.1 ±4.8 minutes versus 80.5 ± 3.6 minutes) and rate of postoperative complications [6.7% (2/30) versus 16.7% (5/30)] (P <0.05).There was no significant difference between the 2 groups in the excellent to good rate by Maryland foot function scoring at the last follow-up [76.7% (23/30) versus 73.3% (22/30)] (P > 0.05).Conclusion Since rapid prototype and 3D printing technology can display the morphology of pilon fracture intuitively and stereoscopically,it helps surgeons with accurate assessment of the fracture.3D printed models of the pilon fracture pre-operatively raise the accuracy of reduction,reduce both operation time and incision complications,and facilitate functional recovery.
2.Alpha 1-antitrypsin Matrix Attachment Region Enhances RNA PolymeraseⅡ-dependent Transcription
Zhi-Yan LI ; Yong ZHANG ;
China Biotechnology 2006;0(04):-
Eukaryotic DNA element called Matrix Attachment Regions (MARs) can function on regulating the structure and activity of chromosome. Traditional quantitation in vitro and indirect functional analysis can not always reflect MAR-involved physiological state. In order to study transcription regulation and make a try in methodism,? 1-antitrypsin MAR (?1-AT MAR) is cloned and incorporated into pEGFP-C1 vector. Non-MAR-containing and MAR-containing plasmids were then transfected into HEK-293 cells with LipofectamineTM 2000 respectively. Positive cell clones were assayed after 20 days of selection by G418. Semiquantitative RT-PCR and fluorescence microscope analysis show that this MAR has a positive effect on modulating nearby gene expression. Further, co-localization with newly CMV promoter and RNA polymeraseⅡ(RNAPⅡ) was detected by chromatin immunoprecipitation (ChIP), The PCR result demonstrates that more RNAPⅡwas recruited to the CMV promoter to initiate transcription in presence of MAR. ChIP can be used to confirm the MAR-mediated transcriptional activation and provide more reliable information than RT-PCR in real time. The technology is also providing a platform for our research in gene expression regulation.
3.DMF-induced adult hepatocyte apoptosis and its effects on expression of Bcl-2, Bax and Caspase-3.
Yan-Yan LU ; Zhi-Qiang XUAN ; Xue-Zhi LI
Chinese Journal of Industrial Hygiene and Occupational Diseases 2008;26(5):276-279
OBJECTIVETo investigate the apoptosis-inducing effect of DMF on the human liver cells (HL-7702) in vitro.
METHODSLiver cells were exposed to different concentrations of DMF (0, 50, 100, 150, 200 mmol/L) for 12 hours. Apoptotic rate, the expression of Bax, Bcl-2 and Caspase-3 in liver cells were measured by FCM and western blotting respectively.
RESULTSThe increase in apoptotic rate of hepatocytes in concentration-manner was shown after DMF treatment for 12 h. After treatment the expression of Bcl-2 was decreased steadily and lower than the control group (P < 0.01), the expression of Bax showed no significant difference among the groups of different dosage by one-factor analysis of variance (P > 0.05), as the increase of the dosage of DMF. The ratio of Bcl-2/Bax dropped with the dosage of DMF increasing, and the ratio in 200 mmol/L of DMF was significantly lower than that of the control (P < 0.01). The new lands of procaspase-3 in 150, 200 mmol/L were observed, which demonstrated that there was active caspase-3.
CONCLUSIONDMF can induce apoptosis of cultured adult normal hepatocytes in vitro, and the mechanism might be related to the decrease of Bcl-2/Bax and the cleavage of Caspase-3.
Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Cells, Cultured ; Dimethylformamide ; pharmacology ; Hepatocytes ; drug effects ; metabolism ; pathology ; Humans ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; bcl-2-Associated X Protein ; metabolism
4.Clinical analysis of 10 patients with hemophagocytic syndrome.
Zhi-hong TAN ; Li-zhi CAO ; Yan YU
Chinese Journal of Pediatrics 2005;43(12):939-940
6.Fracture resistance and failure patterns of open apex root teeth with different posts after endodontic treatment.
Qiuhui, LI ; Ping, YAN ; Zhi, CHEN
Journal of Huazhong University of Science and Technology (Medical Sciences) 2011;31(2):271-6
The aim of this study is to investigate the influence of different posts on the fracture mechanics of endodontically-treated teeth with open apex. Forty-eight human maxillary anterior teeth were collected, and the root was transversely sectioned 12 mm under the cementoenamal junction (CEJ). These samples were then randomly divided into two groups, i.e., minor diameter open apex root (group A) and major diameter open apex root (group B), with mineral trioxide aggregate (MTA) placed into the apical 4 mm in the root canals. Subsequently, both groups were respectively further divided into three subgroups as follows: fiber-post (subgroup 1), metal post (subgroup 2) and non-post (subgroup 3) group. Teeth were restored with a composite resin crown and tested by using a universal testing machine at the rate of 1 mm/min cross-head. Values of the maximum fracture resistance and failure patterns were recorded and compared among all subgroups. In addition, the changes of MTA properties were carefully examined via X-ray photography. Our results indicate that (1) In group A, the mean value of fracture resistance for teeth restored with fiber posts were statistically higher than that with either metal post or non-post; (2) In group B, there was no statistically significant difference in the mean value of fracture resistance among three subgroups; (3) No statistical significance in the mean value of fracture resistance was found between group A and group B; (4) The failure modes of most samples (58%) were irreparable; (5) MTA in two teeth developed cracks after loading tests. In conclusion, endodontically-treated teeth restored with fiber posts are more resistant to fracture than those restored with either metal posts or non-post, and most of the fracture modes are catastrophic in nature.
7.Glyoxalase I-structure,function and role in Alzheimer′s disease
Shijun YAN ; Zhi LI ; Wensheng ZHANG
Chinese Pharmacological Bulletin 2003;0(11):-
Glyoxalase system,a most effective defence system is present in cytosol of cells to scavenge ?-oxoaldehydes,which are reactive intermediates of AGEs formation.Glyoxalase Ⅰ is the key enzyme of this system.?-oxoaldehydes and AGEs are involved in the development of Alzheimer′s disease (AD). Therefore,the expression level and activity of glyoxalase I are essential to pathogenesis of AD.
8.A comparative study between double-threaded compression screws and cannulated lag screws for fixation of Garden type Ⅰ / Ⅱ femoral neck fractures
Yan LI ; Jiang LONG ; Zhi YUAN
Chinese Journal of Orthopaedics 2017;37(17):1069-1074
Objective To compare the results between double-threaded compression screws and cannulated lag screws for Garden type Ⅰ/Ⅱ femoral neck fractures.Methods Data of 56 patients with Garden type Ⅰ/Ⅱ femoral neck fractures who were treated with internal fixation from July 2012 to March 2016 were retrospectively analyzed.According to different fixation,the patients were divided into two groups:double-threaded screws group (group A) including 27 cases (7 males and 20 females,with an average age of 55.5±10.0 years,14 cases Garden type Ⅰ and 13 cases Garden type Ⅱ,the proportion of osteoporosis 10/27;And lag screws group (group B) including 29 cases (8 males and 21 females,with an average age of 57.2±9.5 years,11 cases Garden type Ⅰ and 18 cases Garden type Ⅱ,the proportion of osteoporosis 15/29.The 2 groups were compared with respect to bony fusion time,nonunion,avascular necrosis of femoral head,shortening of femoral neck and Harris Hip Score.Results The average follow-up time was 20.3±8.7 m in Group A and 24.5±7.9 m in Group B.The average bony fusion time was 5.3±0.6 m in Group A and 4.1±0.8 m in Group B,and there was significant difference between the groups (t=5.758,P=0.00).1 avascular necrosis of femoral head was found in both groups.In group A,there were 3 cases of bone nonunion (11.1%,3/27).There were one bone nonunion (3.4%,1/29) case in group B,with no statistically significant difference between groups.Shortening of femoral neck occurred in both groups,the average horizontal shortening was 5.8±2.9 mm and vertical shortening 7.0±3.4 mm in Group A,which were lower than group B (8.2±3.1 mm,9.4±3.6 mm),and the differences showed statistically significant (t=-2.94,P=0.005;t=-2.48,P=0.016).In group A,the average Harris Hip score was 88.2±8.3,while that in group B was 89.9±7.2.There was no statistically significant difference between two groups.Conclusion It seems to us that in the treatment of Garden type Ⅰ/Ⅱ femoral neck fractures,doublethreaded compression screws fixation could reduce femoral neck shortening,but there is no difference on functional outcome compared to cannulated lag screws fixation.On the contrary,double-threaded compression screws fixation is not conducive to fracture healing due to lack of sliding compression.
9.Principles and progress in treatment of talus fracture
Chinese Journal of Orthopaedic Trauma 2021;23(4):329-336
Although talus fractures are not common among foot and ankle injuries, their treatment is difficult because of their complications and poor prognosis. They can be treated conservatively or surgically, with a variety of treatment protocols. At present, the main strategy of surgical treatment is to use strong and effective fixation to restore anatomic structure of the talus and preserve blood supply to the talus as much as possible so that deformity can be avoided and early healing be facilitated. This paper reviews the difficulties and current situation, and summarizes principles and the latest progress in clinical treatment of talus fractures, hoping to provide useful references for the treatment.
10.Screening of Sponge Stelletta tennui Associated Anti-microbial Bacteria and Their Synergistic Effects
Microbiology 1992;0(04):-
A total of 104 marine bacterial strains were isolated from Stelletta tennui around Sanya area of South China Sea by dilution-plate method and were screened for anti-microbial activity on Escherichia coli, Staphylococcus aureu, Pseudomonas fluorescens, Bacillus subtilis, Aspergillus niger, Candida albicans and Pacecilomyces variotii by agar diffusion, paper disc diffusion assay and cell concentration counts methods. It was found that 23 strains, which are 22.2% of the total isolated strains, have anti-microbial activities. Among the 23 strains, A05, A08, A72 and A75 were morphologically, physiologically and biochemically characterized and identified to be the genus Bacillus. At the same time, it was proved that there are positive and negative synergistic effects between or among active strains, e.g., as for A72-75 combination, an obvious enhanced anti-microbial activities on inhibiting Candida albicans and Pseudomomas fluorescens growth was observed than A72 or A75.