Finite element analysis (FEA) is broadly used in biomechanics.Being widely used in clinical studies on cervical spine injury,cervical degeneration and stimulating a variety of cervical spine surgeries,cervical finite element model is becoming more and more accurate in recent years.This paper aims to review the development of cervical finite element model,to introduce the application progress of the modeling and analysis in cervical spine injury,cervical disc arthroplasty,cervical interbody fusion,cervical degeneration and cervical instability,and to prospect the foreground of cervical finite element model in future.

Objective To analyze the relationship between pillow height and cervical intervertebral disc stress in lateral decubitus position of the human body using three-dimensional finite element method,and to provide the basis for appropriate pillow selection.Methods A cervical spine CT scan was performed on a normal male volunteer.The medical 3D image reconstruction software (Mimics),reverse engineering software (Geomagic Studio) and finite element software (MSC.Patran) were collectively used to establish three-dimensional finite element models of the whole cervical spine under three lateral decubitus conditions,includes pillow height of 10 cm (cervical spine leftward flexion),17 cm (cervical spine neutral),and 25 cm (cervical spine rightward flexion).Moreover,the finite element analysis and calculation of the three models were conducted.Results The Von-Mises stress,maximal principal stress and maximum shear stress of the model in cervical spine neutral (pillow height=17 cm) were all significantly lower than those of the cervical spine lateral model.Conclusions When the cervical coronal plane is in neutral position,the cervical discs can achieve the best stress distribution state.In lateral decubitus position of the human body,a appropriate pillow height should make the cervical vertebrae in neutral position.

Objective To analyze and investigate the correlation between the CYP2C19 gene polymorphism and clopidogrel cura-tive effect in the patients with coronary heart disease (CHD) to provide valuable reference information for the future clinical work. Methods A total of 128 cases of CHD undergoing PCI in our hospital from January 2015 to January 2016 were selected as the re-search subjects.All of them were treated with clopidogrel ,the loading dose was 300mg ,and the maintenance dose was 75mg.The subjects were divided into the clopidogrel resistance group and response group.The drug-metabolizing CYP2C19 genotype was com-pared between the two groups and the effect of CYP2C19 genotype on the clopidogrel response was observed.Results Among the subjects ,27 cases were clopidogrel resistance.A total of 16 cases of CYP2C19 slow metabolic gene carriers were detected.There was statistically significant difference between the patients with chronic metabolic genotype VASP-PRI with fast metabolic geno-type and intermediate metabolic genotype(P<0.05).The incidence rate of adverse end point events had statistical difference be-tween the clopidogrel resistance group and clopidogrel response group(P<0.05).Conclusion In the risk factors of clopidogrel re-sistance ,slow metabolism CYP2C19 genotype and clopidogrel resistance will increase the risk of clinical adverse endpoint events oc-currence ,clinic should give adequate attention.

Objective To investigate the number, distribution and metastatic rule of lymph nodes in the mesorectum of rectal cancer specimen after processing the recta] cancer specimen with modified fat clearance technique. Methods Sixty patients with mid-low rectal cancer who had been admitted to Peking University School of Ontology from 2003 to 2008 were assigned to test group. All the 60 patients who denied neo-adjuvant therapy were treated with total mesorectal excision, and the rectums resected were processed with the modified fat clearance technique. Rectums from another 50 patients with mid-low rectal cancer in control group were fixed in formalin solution for 24 hours. The mesorectum was divided into anterior, posterior, left and right quadrants, and each quadrant was further divided into upper, middle and lower parts. The numbers of lymph nodes harvested and metastatic rate of lymph nodes between the 2 groups were analyzed by t test and chi-square test. Results (1) The numbers of lymph nodes harvested in the test and control groups were 1436 and 525, with statistical difference between the 2 groups (t =- 12. 153, P <0.05). The number of small lymph nodes(diameter≤5 mm) harvested in test group was 985. (2) The numbers of lymph nodes harvested in the anterior, posterior and bilateral mesorectum were 125,696 and 615, respectively. The numbers of lymph nodes harvested in the upper, middle and lower part of the mesorectum were 395,534 and 507, respectively. The metastatic rate of lymph nodes in the upper part of the mesorectum was 18.5% (37/200), which was significantly lower than in the middle [43.5% (87/200)] and lower [38.0% (76/200)] part of the mesoreetum (X2= 9. 414, 6.406, P < 0.05). Two hundred metastatic lymph nodes in 33 patients were harvested, 48.0% (96/200) of which with a diameter of ≤ 5 mm. Twenty percent patients had their TNM stage changed after the retrieval of metastatic small lymph nodes. Conclusions Modified fat clearance technique significandy improves the retrieval of lymph nodes, and more small lymph nodes retrieved can increase the accuracy of staging. Rectal cancer cells have strong tendency to disseminate to the distal mesorectum. Adequate excision of the distal mesorectum is key in controlling the local recurrence.

Objective To construct the prokaryotic expression and purification protocols for Pseudomonas aeruginosa type E flagellin (FlgE) and to study its bioactivity.Methods With analysis of Pseudomonas aeruginosa flagellin FlgE sequences,the whole-length FlgE gene was amplified from Pseudomonas aeruginosa genomic DNA by using PCR and primers with proper restriction enzyme sites.The amplified FlgE fragment and prokaryotic expression plasmid pET24a were digested with Nde Ⅰ and Hind ⅢⅣ respectively.The target fragment and vector were recovered and ligated to obtain the recombinant plasmid pET24a-FlgE.DNA sequencing of positive clone confirmed that the target gene and the junctions with vectors were all correct.The plasmid pET24a-FlgE was transformed into BL21 bacteria.The culture conditions like temperature,rotation speed,inducer concentrations,time length were optimized to achieve maximal expression of the target recombinant FlgE with 6×His tag at C terminal.FlgE-His proteins were purified using His-Trap affinity chromatography columns and identified by SDS-PAGE.The purified proteins were further subjected to endotoxin elimination with proper kits.The purified recombinant FlgE was added to cultured corneal epithelial cells for 4 h and the expression of several inflammation-related molecules was examined by using real-time quantitative PCR.Results The recombinant plasmid pET24a-FlgE was successfully constructed and high level FlgE expression was achieved in BL21 with rotation at 16℃ and 1 mmol/L isopropyl-β-D-glucopyranosyl-galactosidase induction for 20 h.Purified recombinant FlgE-His was obtained and used for primary bioactivity assay.After treatment of corneal epithelial cells with 20 μg/ml FlgE for 4 h,the expression of inflammatory cytokines IL-6,IL-8 were significantly increased.Inactivation of the FlgE with ethanol abolished its stimulatory activity.Conclusion The prokaryotic expression and purification system for recombinant Pseudomonas aeruginosa flagellin FlgE was set up,and the recombinant FlgE stimulated the expression of inflammatory factors in corneal epithelial cells.

AIM:To discuss the technique for preparing high-purity solanesol from tobacco. METHODS:The pre-treated tobacco leaves were extracted with mixed solvent of petroleum ether and ethanol,and saponified to obtain solanesol extract; The solanesol extract got through redissolution and dewaxing,then crystallized in the temperatare of -18 ℃; Finally purified by macroporous resin(YPR-Ⅱ,D-1300,HZ-816,HZ-802). RESULTS:The ratio of mixed solvent of petroleum ether and ethanol was 1 ∶ 4,ratio of liquid to materials was 1 ∶ 12,solanesol purity was about 32% after saponification,then crystallization made the purity up to 63. 4% ,finally purified through macroporous resin,the solanesol purity reached above 93. 6%. CONCLUSION:Through the general solvent extraction,saponification,crystallization and macroporous resin adsorption process,the solanesol purity of the product reaches higher than commonly expected values.

Objective To evaluate the effect of pitavastatin on blood glucose in patients with hypercholesterolemia,and to investigate the efficacy of pitavastatin in diabetic patients combined with hypercholesterolemia.Method This study was a 12-week,multi-center,open-label,without parallel-group comparison,phase Ⅳ clinical trail.Results Contrasting to baseline,the prevalences at week 4 and 12 post-treatment of abnormal fasting plasma glucose (FPG) and glycosylated hemoglobin Alc (HbA1c)( FPG:14.2％ vs 14.1％ and 11.0％ ; HbA1c:14.3％ vs 15.1％ and 16.1％ ) in the safety set subjects without diabetes mellitus (DM),as well as in those with DM but not taking glucose-lowering drugs (FPG:7/7 vs 4/7 and 5/7; HbAlc:5/5 vs 4/4 and 5/5) had no significant changes (all P vaules ＞0.05).Contrasting to baseline,the levels of TC [ (6.51±0.94) mmol/L vs (5.12 ±0.93) mmol/L and (4.54 ±1.00) mmol/L],LDL-C [(4.11 ±0.79)mmol/L vs (3.02 ±0.81) mmol/L and (2.51 ±0.70)mmol/L] and TG [2.10(1.53,2.54) mmol/L vs 1.62(1.26,2.00) mmol/L and 1.35(1.10,1.86)mmol/L]at week 4 and 12 post-treatment in the per protocol set 55 subjects with DM were significantly reduced (all P values ＜ 0.05 ) ; 33.3％ of subjects at high risk and 10.0％ of subjects at very high risk had achieved a TC target value; 55.6％ of subjects at high risk and 40.0％ of subjects at very high risk had achieved a LDL-C target value.Conclusion Pitavastatin has a safe effect on blood glucose and it could be used to treat diabetic patients combined with hypercholesterolemia in China.

Objective To summarize the experience in the diagnosis and treatment of hepatic trauma. Methods The clinical data of 260 patients with hepatic trauma admitted from January 1988 to December 2007 were retrospectively reviewed with regard to degree of trauma, treatment methods, therapeutical effects, complications and SO on. Results One hundred and fifty-three eases were treated by operative management,1 07 cases by nonoperative management.236 cases were cured,24 cases died,and the case fatality rate was 10.2%.There were no death among 139 patients with hepatic trauma grades Ⅰ～Ⅱ,22 death among 119 grades Ⅲ～Ⅴ patients, all death of 2 in grade VI, which demonstrated the correlation between death and hepatic trauma grade was statistically significant. Complications appeared in 82 eases, mainly including Secondary hemorrhage, abdominal infection and so on. Conclusions Nonoperative management is suitable for hepatic trauma with stable hemodynamics. Operative management is rapidly selected when the hemodynamics aren't stable. The cooperation of many specialities can enlarge the application of nonoperative management and decrease complications.

40 patients,20 males and 20 females,with 52 miniscrews were included.The concentration of IL-1β,IL-6 and IL-8 in the gingival crevicular fluid around the miniscrews were measured.The results showed that the concentrations of IL-1β,IL-6 and IL-8 increased during orthodintic tooth movement(P ＜0.05),indicating that orthodontic force had an effect on the cytokines around the miniscrews,which may be related to orthodontic bone resorption.

PURPOSE: Details of patients hospitalized for asthma exacerbation in mainland China are lacking. To improve disease control and reduce economic burden, a large sample survey among this patient population is indispensable. This study aimed to investigate the clinical characteristics and outcomes of such patients.METHODS: A retrospective study was conducted on patients hospitalized for asthma exacerbation in 29 hospitals of 29 regions in mainland China during the period 2013 to 2014. Demographic features, pre-admission conditions, exacerbation details, and outcomes were summarized. Risk factors for exacerbation severity were analyzed.RESULTS: There were 3,240 asthmatic patients included in this study (57.7% females, 42.3% males). Only 28.0% used daily controller medications; 1,287 (39.7%) patients were not currently on inhaled corticosteroids. Acute upper airway infection was the most common trigger of exacerbation (42.3%). Patients with severe to life-threatening exacerbation tended to have a longer disease course, a smoking history, and had comorbidities such as hypertension, chronic obstructive pulmonary disease (COPD), and food allergy. The multivariate analysis showed that smoking history, comorbidities of hypertension, COPD, and food allergy were independent risk factors for more severe exacerbation. The number of patients hospitalized for asthma exacerbation varied with seasons, peaking in March and September. Eight patients died during the study period (mortality 0.25%).CONCLUSIONS: Despite enhanced education on asthma self-management in China during recent years, few patients were using daily controller medications before the onset of their exacerbation, indicating that more educational efforts and considerations are needed. The findings of this study may improve our understanding of hospital admission for asthma exacerbation in mainland China and provide evidence for decision-making.
Adrenal Cortex Hormones ; Asthma ; China ; Comorbidity ; Disease Progression ; Education ; Female ; Food Hypersensitivity ; Hospitalization ; Humans ; Hypertension ; Inpatients ; Medication Adherence ; Mortality ; Multivariate Analysis ; Pulmonary Disease, Chronic Obstructive ; Retrospective Studies ; Risk Factors ; Seasons ; Self Care ; Smoke ; Smoking