1.Finite element analysis of femoral neck fracture with different fixation ways
Zhifeng XIA ; Ming LIANG ; Yafeng LI ; Guannan ZENG
Chinese Journal of Tissue Engineering Research 2016;20(31):4630-4636
BACKGROUND:Finite element method is widely used in the femoral neck fracture, but the study concerning different fixation methods of femoral neck fracture is not much. OBJECTIVE:To analyze biomechanical properties of different fixation methods for femoral neck fracture using finite element analysis. METHODS:The femur of voluntters was scanned with CT, at thickness 0.6 mm, from the site above the greater trochanter of the femur. Scanning data were saved in .DICOM format. Data of right proximal femur were imported into Mimics software. Osteotomy was performed according to Pauwels I type fracture. Models of two tensile force screws, ful y threaded hol ow screw and proximal femoral locking plate were established. Three-dimensional finite element method was used to analyze stress distribution, stress concentration position, displacement distribution and maximum displacement in different models of femoral neck fracture with different internal fixation methods. RESULTS AND CONCLUSION:(1) The maximum stress value of two lag screws model was biggest. The maximum stress value of ful y threaded hol ow screw model was minimized. The maximum stresses of two lag screws model, ful y threaded hol ow screw model and proximal femoral locking plate model al were concentrated in the fixed end of fractures. (2) The femoral maximum stress of two lag screws model was biggest. The femoral maximum stress value of proximal femoral locking plate model was minimized. The femoral maximum stresses of two lag screws model, ful y threaded hol ow screw model and proximal femoral locking plate model al were concentrated in the medial femoral smal rotor near and medial femoral and fixation contact points. (3) The maximum displacement of two lag screws model was biggest. The maximum displacement of ful y threaded hol ow screw model was minimized. The maximum displacement of two lag screws model, ful y threaded hol ow screw model and proximal femoral locking plate model al was in the femoral head. (4) The maximum displacement value of two lag screws model fixed place was biggest. The maximum displacement value of ful y threaded hol ow screw model fixed place was minimized. The maximum displacement value of two lag screws model was biggest at femoral head. The maximum displacement value of ful y threaded hol ow screw model was minimized at femoral head. (5) Results showed that the treatment effect of ful y threaded hol ow screw on Pauwels I fractures was better than other two fixation methods.
2.Thermal Desorption-Gas Chromatography or Gas Chromatograph-Mass Spectrometry for Analysis of Semi-Volatile Compounds on Atmospheric Particulate Matters
Hu MENG ; Jinghong ZHAO ; Chunfeng DUAN ; Liang HAO ; Yafeng GUAN
Chinese Journal of Analytical Chemistry 2014;(7):931-936
A thermal desorption ( TD) device was developed and coupled to gas chromatography ( GC) or gas chromatography-mass spectrometry ( GC-MS ) for the qualitative and quantitative analysis of semi-volatile organic compounds on atmospheric particulate matters ( PM ) . The TD was operated by direct heating and placed on the GC injector, leading to high heating rate and easy transfer of analytes to GC without focusing of analytes by cold trap. For establishing the TD-GC method, the materials used for supporting PM samples, temperature and time of thermal desorption, and types of sample injection were investigated for detection of sixteen polycyclic aromatic hydrocarbons ( PAHs) and nine n-alkanes. The limits of detection of the proposed TD-GC method were in the range of 0. 014-0. 093 ng for PAHs, and 0. 016-0. 026 ng for n-alkanes, respectively, with the correlation coefficients of correlation above 0. 9975. The TD-GC method was applied to the determination of trace PAHs and n-alkanes on PM10 samples from three cities. The recoveries were in the range of 95%-135% ( PAHs) and 95%-115% ( n-alkanes) , respectively. Finally, the TD was coupled to GC-MS for comparison of the contents of PAHs and n-alkanes on PMx with different particulate size ( x=10 , 5, 2, 1, 0. 5, 0. 25, 0. 1).
3.Clinical study on blood hemoperfusion resin adsorption series connected continuous venous-venous hemofiltration treating the patients with multiple organ dysfunction syndromes
Luyi LIU ; Yongjian ZHU ; Xiaoli LI ; Yafeng LIANG ; Zuopeng LIANG ; Yonghong XIA
Chinese Journal of Emergency Medicine 2012;21(1):65-69
Objective To investigate the effect of blood hemoperfusion with resin adsorption connected in series to continuous veno-venous hemofiltration ( HP + CVVH) on plasma cytokines such as TNF-α,IL-1β,IL-6 as well as cellular immunity and prognosis of patients with multiple organ dysfunction syndromes (MODS). Methods It was a prospective,randomized clinical trial.A total of 30 patients diagnosed as MODS were randomly (random number) divided into routine treatment + HP + CVVH group (treatment group) and routine treatment + CVVH group (control group).In treatment group,patients received blood hemoperfusion with resin adsorption for 2 hours,and then CVVH for 10 hours every day for 3days.In control group,patients received CVVH for 12 hours every day for 3 days.The plasma samples of patients in treatment group were obtained 0 h,2 h,12 h,24 h,26 h,36 h,48 h,50 h,60 h,5 days,7 days and 10 days after renal replacement therapy.The plasma samples of patients in control group were obtained 0 h,12 h,24 h,36 h,48 h,60 h,5 days,7 days and 10 days after renal replacement therapy.All of these patients were monitored with APACHE Ⅱ score,T-lymphocytes subpopulations,blood lactate acid concentration,heart rate,respiration rate and oxygenation index. Results Plasma levels of TNF-α,IL-1β and IL-6 decreased dramatically after HP (P < 0.01 ) and T-lymphocytes subpopulations CD3+,CD4 +,CD8 + and CD4 +/CD8 + increased after both HP + CVVH and CVVH.The differences in plasma levels of TNF-α,IL-1βand IL-6 of patients between two groups were not noticeably obvious at the intervals of 12 h,36 h,and 50 h after renal replacement therapy. But on the 5 th day after renal replacement therapy,plasma levels of TNF-α,IL-1βand IL-6 of patients in HP + CVVH group were lower than those in control group (P < 0. 05 ).There were 5 fatal patients in HP + CVVH group and 6 patients died off in CVVH group during 28 days after treatment.Conclusions Both HP + CVVH and CVVH could lower the levels of plasma TNF-α,IL-1β and IL-6,and improve cellular immunity and clinical symptoms as well as signs.Compared with CVVH,plasma levels of TNF-α,IL- 1β and IL-6 were lower on the 5th day and increase rate of 28-day survival in HP + CVVH group.
4.Epidemiology and Antibiotic-resistance of Nosocomial Infection Strains of ICU:Ten Year Survey
Yongjian ZHU ; Luyi LIU ; Yafeng LIANG ; Luxin YU ; Zuopeng LIANG ; Yonghong XIA
Chinese Journal of Nosocomiology 2006;0(12):-
OBJECTIVE To observe the type of nosocomial infections in our comprehensive ICU,the prevalence and the vicissitude characteristic of infection strains,and the change of antibiotic-resistance.METHODS To summarize the 10 year results of the monitoring which were divided into three stages to compare the changes with time.RESULTS Gram-negative bacilli were 987(76.4%),Gram-positive cocci 216(16.7%) strains,and 89 strains were fungi(6.9%).The top six strains were in turn:Pseudomonas aeruginosa,Acinetobacter baumannii,Staphylococcus aureus,Klebsiella pneumoniae,Escherichia coli,and Stenotrophomonas maltophilia.Distribution of infection sites: 92.3% infection was in lungs,5.2% in urinary tract infection,2.5% in other sites included lungs,abdomene,CSF,blood etc.CONCLUSIONS The main nosocomial infective pathogens in our ICU are Gram-negative bacilli(75.0%),Gram-positive bacterial infection shows a slight increasing,whereas fungi infection decreasing.In addition to S.maltophilia,the great majority of Gram-negative bacilli,ESBL-producing K.pneumoniae and E.coli maintain a higher sensitivity to carbapenem antibiotic.All Gram-positive cocci to vancomycin and teicoplanin maintain a good sensitivity.In the fungal infection,Candida albicans infection ratio is decreased,while non-C.albicans increases.
5.Geographical distribution rule of normal reference value of old female’s hemoglobin based on factor analysis
Zhiyuan CUI ; Miao GE ; Yafeng LIU ; Shujun ZHANG ; Yan ZHAO ; Wei LIANG
Journal of Jilin University(Medicine Edition) 2006;0(05):-
Objective To reveal the geographical distribution regularity of the normal reference value of old female’s hemoglobin in China,and provide scientific basis for making its unified standards.Methods The normal reference values of 15 690 examples of old female’s hematocrit by the method of hemoglobin cyanide(HiCN)and five geographical factors in 157 areas in China,its distribution regularity and the complex relationship characteristic between geography environment elements were analyzed with the methods of factor analysis,spatial analysis of GIS and correlation analysis.Results By the method of factor analysis,the five factors of geography environment were combined into two common factors F1and F2;the original data was replaced with its scores to infer the regression equation :y^=127.9-0.01009F1-0.01543F2?8.8.And this equation was used to figure out the reference value of 1 288 observation points in China.With support of the model of spatial analysis of GIS,the distribution regulation of old female’s hemoglobin reference value in China and its distribution regularity was west-higher,east-lower,north-higher and south-lower.Conclusion If some area’s altitude(X1),sunshine hours yearly(X2),mean relative humidity yearly(X3),mean temperature yearly(X4),precipitation yearly(X5) are known,this place’s reference value of hemoglobin can be calculated out by using this equation.The reference value of hemoglobin in any areas in China can be gotten from the trend distribution regularity map.
6.CD137 molecule permits single cell sorting and expansion of HIV-specific T cells in vitro
Dan LI ; Hua LIANG ; Bin JU ; Jin FAN ; Yafeng LI ; Shuo WANG ; Yiming SHAO
Chinese Journal of Microbiology and Immunology 2015;(4):305-309
Objective To isolate HIV-specific T cell clone and to expand them in vitro through the activation-induced expression of CD137 molecule.Methods The peripheral blood mononuclear cells were isolated from HIV-infected patients and HIV Gag specific CD3+CD8+CD137+T cell subset were sorted to 96-well plate in 1 cell/well by multicolor flowcytometry and single cell sorting.After 14 days in vitro culture with feeder cells and cytokines, the numbers and phenotypes of the cultured HIV-specific T cells were calcu-lated and identified.Results The CD137 expression was low on rested T cells but up regulated by the stim-ulation with Gag peptide pool.The CD8+CD137+T cells could secret IFN-γ.The number of CD8 T cells reached to 106 after 14 days in culture and expanded to 107-108 cells after 28 days of culture in vitro 100%of the cells remained activated upon Gag stimulation.Conclusion In stead of using IFN-γ, CD137 could be utilized as a novel molecule to isolate and expand HIV specific T cells in vitro.The expanded antigen spe-cific T cell clones could maintain good activation status.
7.Ciliary neurotrophic factor in the regeneration of facial nerve
Zhijun ZHANG ; Bingqing GAO ; Chuanyu LIANG ; Zhigang LIAO ; Jianguo XU ; Yafeng LIU
Chinese Archives of Otolaryngology-Head and Neck Surgery 2006;0(02):-
OBJECTIVE To study the role of ciliary neurotrophic factor(CNTF) in the generation of facial nerve.METHODS Twenty adult New Zealand rabbits' bilateral super buccals of facial nerves were transected and connected with silicone tube.CNTF was injected into a random side of silicone tube and normal saline in the other.At four and eight weeks after the operation, both the CNTF group and the SAL group underwent electrophysiology test and histopathology as well as quantity analysis.RESULTS Four weeks later, both CNTF and SAL group failed in eliciting muscular excitement upon stimulation; T-test showed a signifi-cant difference(P
8.Study of coupled plasma filtration adsorption therapy for patients with severe infection and multiple organ dysfunction syndromes
Xiaoli LI ; Luyi IU ; Jing HU ; Yafeng LIANG ; Meifeng LI ; Xinghan TIAN ; Xifeng WANG ; Qingxia YU ; Jia LIU
Chinese Journal of Emergency Medicine 2017;26(8):919-923
Objective To investigate the effect of coupled plasma filtration adsorption (CPFA) on plasma cytokines:TNF-α,IL-1β,IL-6,cellular immunity,blood lactate acid concentration,heart rate,respiration rate,oxygenation index,hemodynamics,blood cells counts,and prognosis in patients with multiple organ dysfunction syndromes (MODS).Methods This was a prospective,randomized clinical trial in 45 patients diagnosed as MODS.Patients were randomly assigned to hemoperfution with resin adsorption (HP) + continuous venous-venous hemofiltration (CVVH) group,CPFA group and CVVH group.The general clinical data,APACHE Ⅱ score,number of failure organ and previous mentioned biomarkers were documented.Blood samples were collected before and after blood filtration with any one of these procedures.The plasma samples were isolated and stored with frozen at-60 ℃.Data were statistically analyzed with SPSS 13.0 version software.Results In CPFA group,plasma cytokines,TNF-α、IL-1β、IL-6,decreased markedly after plasma adsorption for two hours (P < 0.01);and plasma concentrations of IL-6 were further descended after subsequent CVVH for 10 hours (P < 0.05).In HP + CVVH group,plasma cytokines,TNF-α、IL-1β、IL-6,decreased markedly after HP (P < 0.01),and plasma concentrations of IL-6 were further descended after subsequent CVVH for 10 hours (P < 0.05).In CVVH group,plasma cytokines,TNF-α、IL-1β、IL-6,decreased after CVVH for 12 hours (P < O.05).Blood lactate acid concentration,heart rate,respiration rate,oxygenation index,T-lymphocytes subgroups (CD3 +,CD4 +,CD8 +,CD4 +/CD8 + ratio),clinical symptoms were improved and dose of vasoactive agent was reduced in the patients of three groups without differences among them.The counts of red blood cells,white blood cells and platelets after CPFA and CVVH showed no significant changes.There was no significant difference in blood cell counts between CPFA and CVVH groups.After HP + CVVH,there was a trend of decrease in platelet count (P < 0.05).Platelet counts were significanfly higher in patients treated with CPFA and CVVH group than those in patients treated with HP + CVVH group (P < 0.05).There were 6 patients died in HP + CVVH group,6 patients died in CPFA group and 5 patients died in CVVH group within 28days.Conclusions The comparison of efficacy of blood filtration among 3 modalities of HP + CVVH,CPFA and CVVH showed CPFA had higher capacity of Inflammatory medium scavenging than CVVH,and had less damage effect on blood visible component,especially on platelet compared with HP + CVVH.CPFA was an effective and safety modality in the treatment of the patients with multiple organ dysfunction syndrome.
9.Peptide-RNA complexation-induced fluorescence"turn on"displacement assay for the recognition of small ligands targeting HIV-1 RNA
Liang QI ; Jiayun ZHANG ; Ying GAO ; Pin GONG ; Chengyuan LIANG ; Yao SU ; Qiao ZENG ; Yafeng ZHANG
Journal of Pharmaceutical Analysis 2022;12(6):923-928
The regulator of expression of virion(Rev)protein binds specifically to the Rev-responsive element(RRE)RNA in order to regulate the expression of the human immunodeficiency virus(HIV)-1 genes.Fluores-cence indicator displacement assays have been used to identify ligands that can inhibit the Rev-RRE interaction;however,the small fluorescence indicators cannot fully replace the Rev peptide or protein.As a result,a single rhodamine B labeled Rev(RB-Rev)model peptide was utilized in this study to develop a direct and efficient Rev-RRE inhibitor screening model.Due to photon-induced electron transfer quenching of the tryptophan residue on the RB fluorophore,the fluorescence of RB in Rev was weakened and could be dramatically reactivated by interaction with RRE RNA in ammonium acetate buffer(approximately six times).The interaction could reduce the electron transfer between tryptophan and RB,and RRE could also increase RB fluorescence.The inhibitor screening model was evaluated using three known positive Rev-RRE inhibitors,namely,proflavin,6-chloro-9-[3-(2-chloroethylamino)pro-pylamino]-2-methoxyacridine(ICR 191),and neomycin,as well as a negative drug,arginine.With the addition of the positive drugs,the fluorescence of the Rev-RRE decreased,indicating the displacement of RB-Rev.This was confirmed using atomic force microscopy(AFM)and the fluorescence was essentially unaffected by the addition of arginine.The results demonstrated that RB-Rev can be used as a fluorescent probe for recognizing small ligands that target RRE RNA.The Rev-RRE inhibitor screening model offers a novel approach to evaluating and identifying long-acting Rev inhibitors.
10.Clinical application of bacterial culture and antibody detection for pertussis in children
Wei LIN ; Beibei LIN ; Zhenhai TANG ; Yafeng LIANG ; Guoquan PAN
Chinese Pediatric Emergency Medicine 2020;27(10):737-740
Objective:To explore the application value of bacterial culture and antibody detection of pertussis in children.Methods:A total of 262 children diagnosed with pertussis at the Second Affiliated Hospital and Yuying Children′s Hospital of Wenzhou Medical University from January 2018 to January 2020 were collected as the research objects.Bacterial culture and serum antibody test for pertussis were performed in all cases.According to the gender, age, course of the disease, and whether the children were vaccinated with pertussis vaccine, the patients were divided into different groups and we compared the detection results of different groups.Results:The high incidence age of pertussis was less than 1 year old, mainly less than 6 months old(62.2%). The positive rate of bacterial culture was 82.4%, and the highest positive rate was found in the group of ≤6 months old (94.5%). The positive rate of bacterial culture decreased with the increase of age and course of disease, and the positive rate of children without pertussis vaccination was higher than children with pertussis vaccination( P<0.001). The positive rate of pertussis antibody test was 23.3%.The positive rate of antibody test increased with the increase of age and course of disease and the positive rate of children without pertussis vaccination was lower than children with pertussis vaccination( P<0.001). Conclusion:The high incidence age of pertussis is mainly less than 6 months old.Bacterial culture of pertussis has a good diagnostic value in the early stage of the course, and enzyme linked immunosorbent assay is more helpful in the late stage of the disease.