With the continuously exploration,in recent years,further understanding of anatomical characteristics of the cervical pedicle brings great breakthrough in cervical pedicle screw implantation.In addition,pedicle screw implantation in cervical spine is considered as a technique with high safety and reliability,which can be widely used in cervical trauma fracture,cervical instability,degenerative,inflammatory,benign or malignant tumor,deformity and other neck diseases.Because of the tremendous differences between upper cervical spine (C1,C2) and lower cervical spine (C3-7) in anatomical morphology,cervical pedicle screw implantation in C1 and C2 differs from in lower cervical spine.Due to the similar structure of C3-7,pedicle screw implantation methods are based on the same principle and sharing a few points in common.The pedicle screw technique can be classified in two groups according to the practice methods:navigation technology and manual placement of cervical pedicle screw.Navigation nailing is considered as reliable,easy handing,and with clear operative vision,however,with disadvantages as complex procedures,highly cost operation equipment,and risk in navigation draft.Therefore,manual placement of pedicle screw is more reasonable and practical comparing with the former.In this study,it analyzed anatomical characteristics of lower cervical pedicle and the measurement of pedicle structure,discussed technique of manual placement of pedicle screw in lower cervical spine and biomechanical study of pedicle screw,and summed up the comparison of the advantages and disadvantages of current representative manual placement technology.

Objective: To explore the influence of collagen/fibroin scaffolds containing silver nanoparticles on dermal regeneration of full-thickness skin defect wound in rat. Methods: Eighty-one collagen/fibroin scaffolds containing silver nanoparticles (with the mass concentration of silver nanoparticles as 10 mg/L) and 81 collagen/fibroin scaffolds without silver nanoparticles were produced respectively with freeze-drying method and enrolled as silver nanoparticles scaffold group (SNS) and control scaffold group (CS). Nine scaffolds in each group were cultured with human fibroblasts. At post culture hour (PCH) 2, 12, and 24, the human fibroblasts adherent to the scaffolds (n=3) in two groups were counted. Four full-thickness skin defect wounds were reproduced on the back of each one of the 36 SD rats. The rats were divided into groups SNS (wounds were transplanted with collagen/fibroin scaffolds containing silver nanoparticles) and CS (wounds were transplanted with collagen/fibroin scaffolds without silver nanoparticles) according to the random number table, with 18 rats in each group. In post surgery week (PSW) 1, 2, and 4, 6 rats in each group were sacrificed respectively for general observation, observation of histological structure, inflammatory cell infiltration, and collagen deposition with HE staining, count of CD68 positive cells with immunohistochemical staining, and mRNA expressions of interleukin-6 (IL-6) and IL-10 with real-time fluorescent quantitative reverse transcription polymerase chain reaction. Data were processed with analysis of variance of factorial design, t test, and Bonferroni correction. Results: (1) At PCH 2, 12, and 24, the numbers of human fibroblasts adherent to the scaffolds in the two groups were close (with t values from 1.77 to 2.60, P values above 0.05). (2) In PSW 1, no obvious symptom of infection was observed in wound or wound edge of rats in group SNS with obvious vascularization of scaffolds, while obvious symptoms of infection were observed in wounds of rats in group CS with some scaffolds exfoliated. In PSW 2, the scaffolds were firmly attached to the wounds of rats in group SNS, while obvious contracture was observed in the wounds of rats in group CS with a lot of scaffolds exfoliated. In PSW 4, the scaffolds covered the wounds of rats in group SNS with obvious epithelization on the surface of the scaffolds, while all the scaffolds exfoliated, leaving obvious contracture of residual wounds of rats in group CS. (3) In PSW 1 and 2, compared with those in group CS, more collagen secretion and tissue regeneration and less inflammatory cell infiltration in the scaffolds were observed in the wounds of rats in group SNS. In PSW 4, obvious epithelization was observed in the wounds of rats in group SNS, while inflammatory cell infiltration was observed without obvious epithelization in the wounds of rats in group CS. (4) In PSW 1, the number of CD68 positive cells in the wounds of rats in group SNS [(54±10) /mm²] was similar to that in group CS [(78±7) /mm^2, t=1.52, P>0.05]. In PSW 2 and 4, the numbers of CD68 positive cells in the wounds of rats in group SNS [(154±10) and (77±7) /mm²] were significantly less than those in group CS [(268±16) and (136±13) /mm^2, with t values respectively 7.31 and 3.83, P values below 0.01] respectively. (5) Except for the expression in PSW 4 (t=1.23, P>0.05), the mRNA expressions of IL-6 in the wounds of rats in group SNS in PSW 1 and 2 were significantly lower than those in group CS (with t values respectively 13.12 and 4.65, P values below 0.01). Except for the expression in PSW 1 (t=3.08, P<0.05), the mRNA expressions of IL-10 in PSW 2 and 4 in the wounds of rats in the two groups were similar (with t values respectively 2.14 and 0.49, P values above 0.05). Conclusions Besides good biocompatibility, collagen/fibroin scaffolds containing silver nanoparticles have obvious effect in modulating inflammation, thus they can accelerate dermal regeneration induced by collagen/fibroin scaffolds for wound repair.

Objective To retrospectively analyze the characteristics of events of bus on fire in 6 years in the mainland of China.Methods Events of bus on fire happened between January 2009 and December 2014 were retrieved through Baidu search engine,Chinese Journals Full-text Database,and PubMed database in the search strategy with " bus" and " fire" or " arson" as keywords combined with the name of provinces,autonomous regions,and municipalities of the mainland of China.The occurrence time,region,cause of fire,casualties of each event were recorded,and the correlative analysis was conducted.Data were processed with Microsoft Excel software.Results Totally 287 events of bus on fire were retrieved,among which 49 events happened in 2009,36 events happened in 2010,35 events happened in 2011,37 events happened in 2012,and respectively 65 events happened in 2013 and 2014.The events of bus on fire most frequently happened in June and July,respectively 49 and 39 events.Among the distribution of occurrence regions of events of bus on fire,there were 78 events (27.18％) in east China,52 events (18.12％) in northeast China,41 events (14.29％) both in north China and south China.Among the causes of events of bus on fire,spontaneous combustion of bus ranked in the first (267 events,accounting for 93.03％),followed by arson (13 events,accounting for 4.53％).Among the 13 events of bus on fire caused by arson,7 events happened between 16:00 and 20:00,and 3 events happened between 8:00 and 10:00.Totally 27 events of bus on fire (9.41％) were with casualties,among which 13 events (48.15％)were caused by spontaneous combustion of bus,10 events (37.04％) were caused by arson,and 4 events (14.81％) were caused by traffic accidents.Arson caused the most severe casualties (at least 88 deaths and 287 injuries),followed by spontaneous combustion of bus (at least 35 deaths and 140 injuries) and traffic accidents (at least 9 deaths and 20 injuries).Conclusions Events of bus on fire happened more frequently in recent years in the mainland of China,and the frequencies were much higher especially in June and July.Most events were caused by spontaneous combustion of bus,followed by arson.Most of the events of bus on fire caused by arson happened in the morning and evening rush hours of urban traffic,and althouth the occurrence rate was not high,the casualties were most severe.

Objective:To investigate the correlation between total MRI burden and serum uric acid level in patients with cerebral small vessel disease(CSVD) and its gender differences.Methods:A total of 217 patients with CSVD were retrospectively included as the research objects, and the clinical data such as serum uric acid value were collected.The imaging findings of patients with CSVD were evaluated by MRI, and the total MRI burden score of CSVD was calculated.According to the total MRI burden score of CSVD, patients with CSVD were divided into mild-to-moderate burden group ( n=133) and severe burden group ( n=84). SPSS 20.0 software was used for data analysis and processing.Logistic regression was used to analyze the relationship between uric acid and the total MRI burden score of CSVD. Results:The serum uric acid of severe burden group was higher than that of mild-to-moderate burden group((326.94±70.95)μmol/L, (293.42±80.52)μmol/L, P=0.002). The multivariate logistic regression analysis showed that the elevated level of serum uric acid was an independent risk factors for total MRI burden of CSVD ( β=0.005, OR=1.005, 95% CI=1.001-1.009, P=0.019). The patients with CSVD were equally divided into four group based on the serum uric acid concentration.After controlling the confounding factors, with the increase of uric acid level, the risk of aggravating total MRI burden score of CSVD increased, and the difference was statistically significant( P=0.001). Serum uric acid(for each quartile increase)was an independent risk factor for total MRI burden in male patients with CSVD( β=0.482, OR=1.619, 95% CI=1.125-2.330, P=0.010), while there was no significant difference in female patients( P=0.070). Conclusion:Serum uric acid level is a risk factor for increasing the total MRI burden in male patients with CSVD, but this effect is not found in female patients with CSVD.

Objective To evaluate the role of high-mobility group box 1 protein ( HMGB1)∕Toll-like receptor 4 ( TLR4) signaling pathway in myocardial ischemia-reperfusion ( I∕R) injury in rats. Meth-ods Fifty-four clean-grade healthy male Sprague-Dawley rats, aged 7-8 weeks, weighing 200-250 g, were divided into 3 groups ( n=18 each ) using a random number table method: sham operation group ( group Sham) , myocardial I∕R group ( group I∕R) and specific HMGB1 antibody group ( group H) . Myo-cardial I∕R was produced by 30-min occlusion of left anterior descending branch of coronary artery followed by 180-min reperfusion in anesthetized rats. Specific HMGB1 antibody 2 mg∕kg was injected through the femoral vein at 30 min of reperfusion in group H. Twelve rats in each group were randomly selected at 180 min of reperfusion, and blood samples were collected from the femoral vein for determination of plasma in-terleukin-6 ( IL-6) , IL-8, IL-12, tumor necrosis factor-alpha ( TNF-α) and cardiac troponin I ( cTnI ) concentrations. The rats were then sacrificed, hearts were removed and myocardial tissues were obtained forexamination of the pathological changes and for determination of the expression of intercellular adhesion mol-ecule 1 ( ICAM-1) and E-selectin ( by immunohistochemistry) , expression of TLR4 and NF-κB mRNA and protein (by quantitative real-time polymerase chain reaction or by Western blot), activities of glutathione peroxidase ( GSH-PX) , superoxide dismutase ( SOD) and myeloperoxidase ( MPO) and MDA content. Six rats were selected for measurement of the myocardial infarct volume, and the percentage of myocardial in-farct volume was calculated. Results Compared with group Sham, the serum concentrations of IL-6, IL-8, IL-12, TNF-α and cTnI, MPO activity and MDA content were significantly increased, the expression of ICAM-1, E-selectin, TLR4 and NF-κB protein and mRNA was up-regulated, activities of GSH-PX and SOD were decreased, and the percentage of myocardial infarct volume was increased in group I∕R ( P<0. 01) . Compared with group I∕R, the serum concentrations of IL-6, IL-8, IL-12, TNF-α and cTnI, MPO activity and MDA content were significantly decreased, the expression of ICAM-1, E-selectin, TLR4 and NF-κB protein and mRNA was down-regulated, activities of GSH-PX and SOD were increased, and the percentage of myocardial infarct volume was decreased in group H ( P<0. 01) . Conclusion HMGB1∕TLR4 signaling pathway is involved in myocardial I∕R injury in rats.