Objective To compare the pressure-controlled ventilation (PCV) and volume-controlled ventilation (VCV) in the patients undergoing spinal surgery in prone position supported by a Wilson frame.Methods Forty patients,of ASA physical status Ⅰ or Ⅱ,aged 30-64 yr,with body mass index ＜ 30 kg/m2,scheduled for elective spinal surgery in prone position supported by a Wilson frame under general anesthesia,were randomly allocated to receive mechanical ventilation using either VCV (n =20) or PCV (n =20) mode.Endotracheal intubation and mechanical ventilation were performed after induction of anesthesia.The tidal volume (VT) was set at 10 ml/kg according to the ideal body weight in group VCV.The maximal inspiratory pressure of the anesthesia machine was adjusted to maintain the VT at 10 ml/kg in group P.Both ventilation modes were required to maintain PET CO2 within the normal range.VT,respiratory rate,minute ventilation (MV),dynamic lung compliance (Cdyn),peak and mean airway pressure (Ppeak,Pmean),mean arterial pressure (MAP) and HR were recorded at 10 min after the patients were turned to supine position and at 30 min after the patients were turned to prone position after intubation.Arterial blood samples were collected for blood gas analysis,and oxygenation index(OI) and physiologic dead space fraction (VD/VT) were calculated.Results Compared with those at 10 min after turning to supine position,Ppeak was significantly increased and Cdyn,VT and MV were decreased at 30 min after turning to prone position in both groups.Compared with group VCV,Ppeak was significantly decreased,respiratory rate and Cdyn were increased,and no significant change was found in VT,MV,OI,VD/VT,Pmean,MAP and HR in PCV group.Conclusion Compared with VCV,PCV can improve the ventilatory efficacy and reduce the influence of prone position on respiratory dynamics in the patients undergoing spinal surgery in prone position supported by a Wilson frame.

BACKGROUND:Bone defects are the leading cause of nonunion after firearm injury. Firearm injury is relatively special. Autograft and alograft al have big drawbacks, which cannot meet the requirements of basic-level hospitals. Using tissue-engineered bone with good blood vessels and osteogenic capability in repair of firearm bone defect wil be an ideal and feasible restoration method. OBJECTIVE: To explore the application of human vascular endothelial growth factor 121 gene-modified materials in the repair of firearm-induced radial injury in rabbits. METHODS: A total of 128 rabbits were randomly divided into surgical injury group and firearm injury group (n=64 per group). In the firearm injury group, 0.25 g steel bal was launched using 56-style musket to establish a firearm radial injury model; in the surgical injury group, surgical methods were used to produce a 1.2 cm radial injury model. Human vascular endothelial growth factor 121 gene-modified materials were used. The related histocytes from rabbits were harvested to obtain bone marrow stromal cels for culture. A porous scaffold material was prepared. The obtained materials were respectively implanted into radial defect sites in the surgical injury and firearm injury groups. The application of human vascular endothelial growth factor 121 gene-modified materials in rabbit radial defect repair was analyzed. RESULTS AND CONCLUSION: Compared with the surgical injury group, at 8, 12 and 16 weeks after repair, the gray level ratio of bone defect site and the anti-compression mechanical ratio at the healthy and repairing sides of the radius in the firearm injury group were decreased (P < 0.05), and the new bone area increased (P < 0.05). At 2 and 4 weeks after repair, the local blood flow at the repair area was significantly increased (P < 0.05). These results suggest that compared with the surgical injury group, the curative effect of human vascular endothelial growth factor 121 gene is more ideal in the firearm injury group because of the emergence of local ischemia and hypoxia in the process of radial defect repair. Human vascular endothelial growth factor 121-modified material can repair bone marrow stromal cels. The application of human vascular endothelial growth factor 121 in firearm burns can enhance the synthesis and secretion of angiogenic factors, improve the local blood flow, reduce anti-compression mechanical ratio, and increase the new bone area.

Objective To investigate the effects of gefitinib on early embryonic development and expression of abcb4 tumor resistance genes in zebrafish.Methods Zebrafish were adopted as experimental animals and divided into gefitinib group,mixture of doxorubicin and gefitinib group and blank group.Zebrafish embryos of 0.5-1.5 hours after fertilization(0.5-1.5 hpf) were exposed to different concentrations of gefitinib,and then embryo development of zebrafish in 24-120 hpf was observed and the number of death,hatch and malformation was recorded.The embryo mortality was calculated under different concentrations of gefitinib at different time points,and the numerical value of IC50 was calculated;Hatching rates of zebrafish embryo in 48 hpf and 72 hpf and malformation rates of zebrafish embryo in 120 hpf were calculated.The zebrafish embryos exposed to different concentrations of gefitinib in different groups were collected,and the expressionof abcb4 gene in zebrafish embryos was detected by real-time quantitative PCR.Results Gefitinib IC50 in zebrafish embryos was 16.18 μmol/L.Compared with the control group,higher dosage (20 μmol/L) of gefitinib in other two groups significantly decreased hatching rates of embryos,and had obvious embryonic lethal effects and teratogenic effects.Moreover,the mRNA levels of the abcb4 gene in the zebrafish embryos of gefitinib group were not significantly changed,whereas the mRNA levels of the abcb4 gene in mixture of doxorubicin and gefitinib group were significantly different(P＜0.05).Conclusion Gefitinib has no significant effects on the expression of abcb4 tumor resistance gene in early development of zebrafish embryos(P＞0.05),but it can reverse the drug resistant effects of doxorubicin,suggesting that zebrafish can construct tumor resistance model.

Objective To explore distribution characteristics and risk factors of cerebral microbleeds (CMBs),and the correlation between CMBs and white matter lesions (WML) in patients with ischemic cerebrovascular disease(ICVD).Methods 180 patients with ICVD in neurology department of Hebei General Hospital from February 2015 to January 2017 were recruited.Those patients were underwent brain magnetic resonance imaging (MRI),and magnetic susceptibility weighted imaging (SWI).Recorded the baseline data and risk factors of high blood pressure,diabetes,hyperlipidemia,and high homocysteine were recorded.Patients with CMBs were counted and graded to understand the characteristics of CMBs distribution.Logisitic regression analysis was used to analyze the influencing factors.ICVD patients were divided into CMBs group and non CMBs group.CMBs group was further divided into 4 groups according to the severity,which was divided into level 1-3.The correlation between CMBs influencing factors and classification was further studied.Then patients with ICVD were divided into WML group and non WML group.WML group scored each region with age-related white matter changes rating scale (ARWMCrs).The correlation between WML and CMBs classification was further studied.Results (1) The overall prevalence of CMBs in patients with ICVD was 61.7％ (111/180).The most common location of CMBs in patients with ICVD was the cortical and subcortical regions (80/111,72.1％),followed by the basal ganglia and thalamus regions (61/111,55.0％),and the infratentorial regions(38/111,34.2％).The difference between them were significant (x2 =32.061,P=0.000).In cortical and subcortical regions of CMBs,temporal lobe was the most common (61.3％).(2) Age(B=0.046,Or=1.047,95％CI =1.017～ 1.077,P=0.002) and the high homocysteine (B =1.458,Or=4.299,95％ CI =2.114 ～ 8.744,P＜0.001) were the risk factors for CMBs.(3) Four classification of CMBs was positively correlated with and WML total score (r=0.393,P=0.393).Conclusion The temporal lobe was the most common region for CMBs in patients with ICVD.Age and high homocysteine were risk factors for CMBs.With the increase of WML total score,severity of CMBs was also increased.

Human APOBEC3G (hA3G) is a cytidine deaminase which inhibits HIV-1 replication. The HIV-1 accessory protein viral infectivity factor (Vif) counteracts with hA3G by targeting it for proteasomal degradation. In this work, we constructed and optimized molecular models of the hA3G dimer and the hA3G-Vif complex. The molecular modeling study revealed that the loop7 motif of hA3G appears on the interfaces of both the hA3G-Vif complex and the hA3G dimer. Biochemical analysis provided evidence suggesting that binding of Vif to hA3G results in steric blocking of hA3G dimerization, implying that monomeric hA3G serves as a substrate for Vif-mediated degradation. Furthermore, we presented evidence for the important roles of the loop7 motif, especially the central residues within the region, in hA3G dimerization, hA3G--Vif interaction, Vif-mediated hA3G degradation as well as subcellular localization of hA3G. This work highlights a multiple-task interface formed by loop7 motif, which regulates biological function of hA3G, thus providing the feasibility of the strategy of blocking Vif-mediated A3G degradation by targeting the putative site around loop7.