1.Influence of Width and Thickness of DCI's Curved Section on Its Performance.
Jia BAI ; Tao WANG ; Xuejin CHENG ; Lei WU ; Xiangjun HU
Chinese Journal of Medical Instrumentation 2016;40(1):10-12
By establishing a series of Dynamic Cervical Implants (DCI) within C5-C6 cervical spinal segments, the biomechanical finite element analysis for DCI with different width and thickness were carried out to investigate the influence of the width and thickness of DCI's curved section on its equivalent stress and range of motion (ROM), so as to provide some theoretical basis for the optimization of DCI's design. The results show that the width of DCI's curved section has more obvious influence on the ROM of lateral bending and torsion, in comparison with the thickness of DCI's curved section. By appropriate reduction in width, the ROMs of lateral bending and torsion increase obviously, i.e. the overall movement function of patients is improved. Furthermore, the increase of equivalent stress could be counteracted by corresponding increase of thickness.
Biomechanical Phenomena
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Cervical Vertebrae
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Finite Element Analysis
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Humans
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Movement
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Neck
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Prostheses and Implants
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Prosthesis Design
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Range of Motion, Articular
2.Biomimetics of crystal texture in dental enamel prism by self-assembly oligopeptide
Lei WANG ; Wei BAI ; Hailan FENG ; Xinru JIA
Journal of Peking University(Health Sciences) 2004;0(01):-
Objective: To evaluate the possibility of self-assembly oligopeptide(T2) for dental enamel biomimetics, especially for the prism’s crystal texture since it could prompt calcium phosphate precipitated in gel carrier. Methods:SEM (Scaning electron microscope) and TEM (Transmission electron microscope) were used to observe the morphologic presentation and ED(Electron diffraction) to crystal texture comparing with the human molar enamel powder. Results: (a) Flake-like and needle-like octacalcium phosphate precipitated in the gel carrier with self-assemble oligopeptide(T2). They transformed into rod-like hydroxyapatite crystals gradually in the following 2-4 weeks. (b) The rod-like hydroxyapatite may arrange or grow into bundles which are similar to the human enamel prisms in both appearance and size. (c) The rod-like hydroxyapatite showed polycrystal while the enamel prisms showed monocrystal under examination of ED. Conclusion:The self-assemble oligopeptide(T2) could regulate the speed of nucleation and crystallization of hydroxyapatite in morphology and crystalline size. Thus, the self-assembly oligopeptide and the gel carrier mineralization system could be primarily applied in biomimetic use for the crystallization of hydroxyaptite in dental prism in vitro.
3.Safety Evaluation for Interventional Radiotherapy with X-ray Angiography
Yani BAI ; Shu QIAN ; Zifu HE ; Min JIA ; Xiao FAN ; Lei JIN
Chinese Medical Equipment Journal 2003;0(10):-
Objective To evaluate the safety of interventional radiotherapy with X-ray angiography. Methods To compare X-ray radiation levels with and without radioprotect with X-ray protective monitor by simulating operators' body's parts. Results The difference is significant. Conclusion Interventional radiotherapy with angiography with effective protect is safe.
4.Effects of controllable dynamic inhaled exposure of moxa smoke on LDL-r, ICAM-1 and morphology of heart tissue in rats.
Jia YANG ; Bai-Xiao ZHAO ; Li HAN ; Ping LIU ; Lei WANG ; Hua BAI ; Jian HUANG ; Jun-Tian LIU ; Chang HUANG ; Mao-Xiang ZHU ; Zhi-Hua YANG
Chinese Acupuncture & Moxibustion 2014;34(6):573-577
OBJECTIVETo observe the change of lipid metabolism and vascular endothelium as well as morphology of heart tissue in rats who were long-time exposed to moxa smoke with different concentrations in order to provide reference for safety assessment of moxa smoke on cardiovascular system.
METHODSOne hundred and sixty-eighty Wistar rats were randomly divided into a control group, a low-concentration group, a median-concentration group and a high-concentration group, 42 rats in each one. The rats were exposed to moxa smoke with concentration of 0%, 10%, 40% and 70%, respectively, for 20 min per day. After continuous intervention for six months, enzyme-linked immunosorbent assay (ELISA) was applied to measure the level of low density lipoprotein-receptor (LDL-r) and intercellular adhesion molecule-1 (ICAM-1) in blood serum in each group; the slices of heart tissue were stained with hematoxylin-eosin staining method to observe morphology change of heart tissue.
RESULTS(1) After the intervention of moxa smoke, the levels of LDL-r and ICAM-1 in the low-concentration group were not statistically different from those in the control group (both P > 0.05); the level of LDL-r in the median-concentration group was significantly increased, which was statistically different from that in the control group [(3.87 +/- 0.27) mg/mL vs (2.12 +/- 0.13) mg/mL, P < 0.01], however, the content of ICAM-1 was not obviously changed; although the level of LDL-r in the high-concentration group was presented with an escalating trend, it was not statistically different from that in the control group (P > 0.05) while the level of ICAM-1 was obviously increased (P < 0.01). (2) Under the light microscope, the abnormalities of cardiac muscle fibers and myocardial cell in each group were not been observed.
CONCLUSIONThe long-time intervention of low-concentration moxa smoke has no significant effects on lipid metabolism and vascular endothelium of rats, indicating that clinical application of low-concentration moxa smoke is relatively safe. The long-time intervention of moderate-concentration moxa smoke could significantly increase the clearance rate of cholesterol, implying the beneficial regulation of moxa smoke on lipid metabolism. The high-concentration moxa smoke could induce certain damage to vascular endothelium but its mechanism is in need of further research. The pathologic change of heart tissue could not be induced by moxa smoke with any concentration.
Animals ; Heart ; anatomy & histology ; Intercellular Adhesion Molecule-1 ; metabolism ; Lipid Metabolism ; Male ; Moxibustion ; adverse effects ; Myocardium ; pathology ; Rats ; Rats, Wistar ; Receptors, LDL ; metabolism ; Smoke ; adverse effects ; analysis
5.Micronucleus in vitro induced by inhalable particulate matters in moxa smoke.
Li HAN ; Hai HU ; Jia YANG ; Hua BAI ; Lei WANG ; Juntian LIU ; Chang HUANG ; Yaomeng LIU ; Lue HA
Chinese Acupuncture & Moxibustion 2016;36(5):499-503
OBJECTIVETo investigate whether inhalable particulate matters can cause the damage of chromosome or mitotic apparatus to produce micronucleus, and to evaluate genetic toxicology of moxa smoke on chromosome.
METHODSBy MTT method, the 24 h half maximal inhibitory concentration (IC50) of moxa smoke condensation (MSC) on Chinese hamster ovary (CHO) cells was 0.087 mg/mL. CHO cells, which were cultured in vitro, were divided into a solvent control group, a positive control group (cyclophosphamide as solvent), a low concentration group, a moderate concentration group and a high concentration group. The low concentration group, moderate concentration group and high concentration group were set approximately 1/8, 1/4, 1/2 of IC50, respectively. Whether micronucleus had dose-effect response induced by the damage of chromosome or mitotic apparatus was observed after CHO cells were contaminated by MSC in the low concentration group, moderate concentration group and high concentration group.
RESULTSThe rate of micronucleus induced by MSC in the low concentration group, moderate concentration group and high concentration group was higher than that in the solvent control group (all P < 0.05), which presented dosage-effect response. The experiment was repeated 3 times, indicating it was repeatable with statistical significance.
CONCLUSIONHigh concentration of MSC shows toxicity to induce chromosome damage, which disappears at low concentration. The genetic toxicology is also dependent on concentration, and the concentration of moxa smoke is essential. In clinical treatment, it is noted to control the level of moxa smoke, while the clinical safety standard of moxa smoke concentration is in need of further study.
Air Pollutants ; adverse effects ; Animals ; CHO Cells ; Cell Nucleus ; drug effects ; genetics ; Cricetinae ; Cricetulus ; Inhalation Exposure ; adverse effects ; analysis ; Micronucleus Tests ; Moxibustion ; adverse effects ; Particulate Matter ; adverse effects ; Smoke ; adverse effects ; analysis
6.Effect of bone marrow-derived mesenchymal stem cells on mTOR signaling pathways in lung tissues of rats with acute lung injury
Lei WANG ; Yanhui BAI ; Jun JIA ; Qingping WEN ; Yanling DING
Chinese Journal of Anesthesiology 2018;38(4):484-488
Objective To evaluate the effect of bone marrow-derived mesenchymal stem cells (BMSCs) on mammalian target of rapamycin (mTOR) signaling pathways in lung tissues of rats with acute lung injury (ALI).Methods Healthy pathogen-free adult male Sprague-Dawley rats were selected,and the BMSCs were obtained and cultured in vitro.One hundred and five healthy clean adult male SpragueDawley rats,weighing 170-190 g,were divided into 5 groups (n=21 each) using a random number table:control group (group C),PBS group,group ALI,ALI plus BMSC group (group ALI+BMSCs),and ALI plus phosphate buffer solution (PBS) group (group ALI+PBS).Group C received no treatment.PBS 0.5 ml was injected via the tail vein in group PBS.Lipopolysaccharide (LPS,0.5 ml) 5 mg/kg was intraperitoneally injected to establish the model of ALI in group ALI.BMSCs (0.5 ml) 1×104 cells/ml were injected via the tail vein after intraperitoneal injection of LPS in group ALI+ BMSCs.PBS 0.5 ml was injected via the tail vein after intraperitoneal injection of LPS in group ALI+PBS.Arterial blood samples were collected for blood gas analysis at 6,24 and 48 h after injection of BMSCs.Lungs were then removed for determination of wet/dry weight ratio (W/D ratio) and expression of mTOR,nuclear factor kappa B (NF-κB) and tumor necrosis factor-alpha (TNF-o) in lung tissues (by Western blot) and for examination of the pathologic changes of lungs tissues (using haematoxylin and eosin staining).Results Compared with group C,pH value and PaO2 were significantly decreased,PaCO2 and W/D ratio were increased,and the expression of mTOR,NF-κB and TNF-α was up-regulated at each time point in ALI,ALI+BMSCs and ALI+PBS groups (P<0.05).Compared with group ALI,pH value and PaO2 were significantly increased,PaCO2 and W/D ratio were decreased,the expression of mTOR,NF-κB and TNF-α was down-regulated at each time point (P<0.05),and the pathologic changes of lungs tissues were significantly attenuated in group ALI+BMSCs.Conclusion The mechanism by which BMSCs reduce ALI may be associated with inhibiting mTOR signaling pathways in lung tissues of rats.
7.In vitro biomineralization of self-assembly oligopeptide T2.
Lei WANG ; Wei BAI ; Hailan FENG ; Xinru JIA
Journal of Biomedical Engineering 2007;24(4):798-801
Oligopeptide T2, a kind of PA (Peptide Amphiphile) molecule, which could build up nano-fiber by self-assembly was designed and synthesized in this study. And the double-diffusion gel system was applied on this molecule to investigate its biomineralization features in vitro. The results showed that T2 could obviously reduce the hydroxyapatite (HA) formation period. And HA was found to possess the characteristics of non-crystalline by analysis of X-ray diffraction (XRD) and scanning electronic microscopy (SEM). These findings point to the conclusion that the negatively charged zone in T2 might make this molecule have the function of promoting HA biomineralization in vitro. And the mechanism responsible for the procession of HA biomineralization needs further research.
Biocompatible Materials
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chemical synthesis
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chemistry
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Bone Substitutes
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chemistry
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Calcification, Physiologic
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Durapatite
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chemistry
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Oligopeptides
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chemical synthesis
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chemistry
8.Thermal tissue effects of the second-generation argon plasma coagulation on human stomach tissue :An ex vivo study
Li ZHANG ; Lei DONG ; Jia LIU ; ming Yi LI ; yang Shi MA ; cang Bai ZOU
Journal of Xi'an Jiaotong University(Medical Sciences) 2018;39(1):84-87,92
Objective To explore the thermal effects of the second-generation argon plasma coagulation (VIO APC/APC2) on ex vivo human stomach tissue with different mode ,output power and application time .Methods The thermal effects of VIO APC were studied on fresh surgery-resected human stomach tissues .Different output powers were combined with mode "forced (F )","pulse , effect 1 (P1 )" and "pulse , effect 2 (P2 )";three application time ,the depth and maximum diameter of each injury were recorded .Results The depth of tissue injuries was correlated with output power (P<0 .001) ,energy (P=0 .008) and mode (P=0 .013) .The maximum diameter of injuries was correlated with output power (P<0 .001) ,application duration (P=0 .001) ,energy (P<0 .001) and mode (P=0 .001) .The incidence of harmful damage was only related to mode (P=0 .012) .The depth of tissue injuries was P1> F> P2 (P<0 .05) ,and the maximum diameter of injuries was P2> P1> F (P<0 .05) . Conclusion Different modes of VIO APC can create different thermal effects on the gastric tissues .Compared with F mode ,P1 mode creates deeper injuries while P2 mode creates larger but shallow injuries .All the three modes may cause injuries involving muscularis propria .
9.Etiological detection of severe hand-food-mouth disease and related genetic characteristics of enterovirus type 71 infection in Beijing,2010
Jie LI ; Mei QU ; Lei JIA ; Xin ZHANG ; Bai-Wei LIU ; Fang HUANG ; Xin-Yu LI ; Quan-Yi WANG
Chinese Journal of Epidemiology 2012;33(9):926-929
Objective To study the etiological detection on samples from severe hand-footmouth disease (HFMD) cases and the genetic characteristics of enterovirus type 71 (EV71) isolates lrom severe patients in Beijing,2010.Methods Real-time RT-PCR was used to detect EV71 and Coxsackievirus A16 (CoxA16) and RD cells were used to separate virus strains from samples.Homogeneity of EV71 isolated strains were also analyzed. Results Four hundred and fourty-two severe cases were detected and 253 were positive,taking up 57.24% of the total (253/442).The overall positive detection rate on EV71 was 54.55% (138/253),with CoxA16 as 5.93%(15/253),and with other enterovirus group was 39.53%(100/253).The nucleotide homogencity of VP1 within these 12 strains was 97.2% 100.0%,and with Beijing strains in 2007-2010,Shandong strains in 2007 and Anhui Fuyang strains in 2008 and the Guangdong strains in 2008 as 94.0%-99.9%.Conclusion Severe HFMD cases were most oftenly caused by EV71 but less caused by CoxA16 or other cnterovirus.The HFMD in 2010 in Beijing was mainly caused by EV71 subgenotype C4a with 4 transmission chains.Twclve isolated EV71 strains had high homogeneity with strains isolated from severe cases in Anhui Fuyang in 2007.
10.A study on common bile duct primary suture after laparoscopic choledocholithotomy with bile duct decompression tube
Peihu YAN ; Yanling MA ; Yuling BAI ; Fuqiang YU ; Liang GUO ; Guojun WANG ; Lei WANG ; Jiemin WANG ; Ping JIA ; Chunmei ZHAO ; Xiaojuan DONG ; Xia LI ; Hao CHEN
Chinese Journal of General Surgery 2018;33(10):861-864
Objective To evaluate intraoperative placement of bile duct decompression drainage tube in CBD primary suture after laparoscopic choledocholithotomy.Methods 152 patients undergoing laparoscopic choledocholithotomy were divided into group A (placement of bile duct decompression drainage tube during operation,82 cases) and group B (no decompression drainage tube placement,70 casas).Results There was no significant difference in operative time and intraoperative bleeding between the two groups (P > 0.05).In group B patients the abdominal drainage tube indwelling time,abdominal drainage volume,peritoneal drainage fluid bilirubin value,postoperative hospitalization time were significantly longer than group A,the difference was statistically significant (P < 0.05).No recurrence of choledocholithiasis and biliary stricture were found in either groups.Conclusions Placement of bile duct decompression drainage tube in laparoscopic choledocholithotomy and CBD primary suture after laparoscopic choledochotomy can significantly reduce the incidence of biliary leakage and shorten the postoperative hospital stay.