ObjectiveTo study the effects of intermittent subglottic secretion drainage(SSD)with an endotracheal tube on incidience of ventilator- associated pneumonia(VAP). MethodsWe searched computerized databases,including Cochrane library,Pubmed,EMbase,CBM,CNKI,Wanfang and some relevant databases from initializing to March 2012,extracting data about subglottic secretion drainage(SSD)with an endotracheal tube on incidence of VAP using RCT.The data had Meta- analysis by software RevMan5,and to those data which could not be conversed or merged,they underwent descriptive analysis. ResultsWeidentifled 5 randomized clinical trials that met the inclusion criteria with a total of 683 randomized patients.In Meta- analysis,the overall risk ratio for ventilator- associated pneumonia was decreased significantly by intermittent subglottic secretion drainage with an endotracheal tube.There was no significant difference on adverse events or on hospital or intensive care unit mortality.Databases,including ICU and hospital LOS,duration of endotracheal catheterization,bacteria concentration,which were difficult to be conversed and obtained full data,they underwent a descriptive research. ConclusionsCompared with the common endotracheal tubes,the use of endotracheal tubes with subglottic secretion drainage is effective for prevention of ventilatorassociated pneumonia.But it has no effect on adverse events or on hospital or intensive care unit mortality.So large sample RCTs with multiply- center should be carried out to assess the effect of the use of SSD.

Background:Fenretinide,which is capable of generating reactive oxygen species( ROS ),has emerged as a promising antineoplastic agent based on numerous in vitro and in vivo studies and clinical chemoprevention trials. Preliminary studies showed that fenretinide could induce apoptosis in human hepatocellular carcinoma( HCC)cells in vitro, however,the precise mechanism was not clarified. Aims:To elucidate the effect of ROS on apoptosis of human HCC cells induced by fenretinide and the underlying mechanism. Methods:Human HCC cell line Huh-7 was treated with antioxidant vitamin E,fenretinide or their combination,respectively. ROS in live cells was evaluated by confocal microscopy and flow cytometry;cell viability and apoptosis were assessed by CellTiter-Glo Luminescent Cell Viability Assay Kit and Caspase-Glo3/7 Assay Kit;expression and intracellular localization of nuclear receptor Nur77,as well as expression of stress-induced transcription factor GADD153 were measured by immunofluorescence staining and Western blotting,respectively. Results:Vitamin E pretreatment fully blocked the fenretinide-induced ROS production. In Huh-7 cells pretreated with vitamin E,cell apoptosis induced by fenretinide was significantly reduced(P<0. 05). Furthermore,effect of vitamin E pretreatment was noteworthy on reducing fenretinide-induced GADD153 expression, while no significant impact on fenretinide-induced Nur77 expression and translocation was observed. Conclusions:Elimination of ROS by vitamin E can abrogate the pro-apoptotic effect of fenretinide on Huh-7 cells,which indicates the participation of ROS in fenretinide-induced apoptosis of human HCC cells. Its mechanism might be associated with induction of GADD153 protein expression.

Objective To study CT numbers correction of kilo?voltage cone?beam CT (KV?CBCT) images for dose calculation. Method Aligning the CBCT images with plan CT images, then obtain the background scatter by subtracting CT images from CBCT images. The background scatter is then processed by low?pass filter. The final CBCT images are acquired by subtracting the background scatter from the raw CBCT. KV?CBCT images of Catphan600 phantom and four patients with pelvic tumors were obtained with the linac?integrated CBCT system. The CBCT images were modified to correct the CT numbers. Finally, compare HU numbers between corrected CBCT and planning CT by paired T test. Evaluate the image quality and accuracy of dose calculation of the modified CBCT images. Results The proposed method reduces the artifacts of CBCT images significantly. The differences of CT numbers were 232 HU, 89 HU, 29 HU and 66 HU for air, fat, muscle and femoral head between CT and CBCT respectively (P= 0?? 39,0?? 66,0?? 59,1).The differences of CT numbers between CT and CBCT was reduced to within 5 HU. And the error of dose calculation with corrected CBCT images was within 2%. Conclusions The CT numbers of corrected CBCT are similar with plan CT images and dose calculations based on the modified CBCT show good agreement with plan CT.

Erbium，chromium：yttrium scandium gallium garnet（Er，Cr：YSGG）laser is mainly used for root canal treatment，periodontal disease，tooth decay，dentin hypersensitivity，pulp amputation，etc in the field of dentistry.This paper mainly describes the research progress of Er，Cr：YSGG laser in root canal therapy from following four as⁃pects：root canal sealing，sterilization，cavitation effect and the effect on periapical tissue. The experimental results showed that when the operation parameters of Er，Cr：YSGG were 2 ~ 4 w and 20 Hz，it could effectively remove the stained layer of dentin tubules and improve the tightness between materials and dentin. The thermal effect produced by Er，Cr：YSGG energy has a sterilizing effect，while the optical conductivity of the tooth enables the rinse solution to enter deeper tissues，further improving the sterilizing effect. Er，Cr：YSGG also has a cavitation effect，which destroys the surface tension of the deep solution，removing the stain layer and bacteria in the deep layer. However，with the same operation parameters，if Er，Cr：YSGG is not used properly，the thermal effect of Er，Cr：YSGG will cause some damage to the periapical tissues. Therefore，reasonable use time of Er，Cr：YSGG and water cooling conditions are important.

Objective To investigate the mRNA expression and methylation status of IL-13 receptor(IL-13R)α1 gene in peripheral T lymphocytes of patients with systemic lupus erythematosus(SLE).Methods Venous blood samples were obtained from 10 SLE patients(5 in active phase,5 in inactive phase)and 6 normal human controls.CD4+ and CD8+ T cells were isolated from these samples via magnetic activated cell sorting(MACS).Real-time quantitative PCR was used to test the mRNA expression of IL-13Rα1 gene,and methylation specific PCR to detect the methylation status.Results The expression level of IL-13Rα1 mRNA was 2.224±0.251,1.712±0.132.and 1.104±0.044 in CD4+ T cells of active SLE patients,inactive SLE patients and controls,respectively;the difference between the three groups was statistically significant(all P＜0.05).The expression level of IL-13Rα1 mRNA in CD8+T cells was significantly higher in active SLE patients than that in the normal controls(1.672±0.142 vs 1.238±0.106,P＜0.05),while no difference was noted between inactive and active SLE patients or normal controls.The methylation index of IL-13Rα1 gene was 0.454±0.023.0.635±0.065.0.844±0.097 in CD4+T cells of active SLE patients,inactive SLE patients and normal controls,respectively,and the difference between the three groups was significant(all P＜0.05),while no significant difference was observed in the methylation index in CD8+T cells among these groups(P＞0.05).The IL-13Rα1 mRNA expression in CD4+T and CD8+T cells was positively correlated with SLE disease activity index(SLEDAI)score(r=0.79,0.76,P=0.007,0.02 respectively).A negative correlation was found between the methylation level Of IL-13Rα1 in CD4+T cells and SLEDAI score(r=-0.89.P＜0.0 1).as well as between the IL-13Rα1 mRNA expression and its methylation level(r=-0.84,P＜0.0 1).Conclusion The development of SLE may be related to the overexpression of IL-13Rα1 gene induced by DNA hypomethylation in T cells.

Objective:To explore the effect of hydrogen sulfide (H 2S) on modulating the subunit Kir6.2 of adenosine triphosphate sensitive potassium channels via the cyclic guanosine monophosphate-dependent protein kinase (cGMP/PKG) signaling pathway in epileptic rat models. Methods:Sixty adult male SD rats were randomly divided into the following six groups (10 rats in each group) by random number table method: control, epileptic, H 2S donor, H 2S donor+epileptic, KT5823 (one inhibitor of the cyclic guanosine monophosphate-dependent protein kinase)+H 2S donor+epileptic, and glibenclamide (one inhibitor of the adenosine triphosphate sensitive potassium channels)+H 2S donor+epileptic groups. Except the control group, SD rats were intraperitoneally injected with plentylenetetrazole to make the kindling models and their behaviours were recorded including the latency period, the grade, and the duration of the first epileptic seizure according to the Racine′s standard. The waveforms of electroencephalogram (EEG) in hippocampus were also recorded during the seizure. The mRNA and protein levels of PKG and Kir6.2 in hippocampus were evaluated by Western blotting and quantitative real-time polymerase chain reaction, and the hippocampal concentrations of cGMP and phosphorylation of cyclic guanosine monophosphate-dependent protein kinase (p-PKG) were detected by enzyme linked immunosorbent assay. Results:Rats in the epileptic group showed Ⅳ-Ⅴ grade of epileptic seizure [4.500 (4.000, 4.875)], short latency period [(10.37±8.21) min] but long duration [(69.50±24.37) s] of seizure. Compared to the epileptic group, rats in the H 2S donor group showed Ⅱ-Ⅲ grade of epileptic seizure ( P=0.004), significantly longer latency period ( P<0.001), and shorter duration of seizure ( P<0.001). Compared to the H 2S donor+epileptic group, rats in the KT5823+H 2S donor+epileptic group showed Ⅲ-Ⅳ grade of epileptic seizures, significantly shorter latency period ( P<0.001), and longer duration of seizure ( P<0.001). The results of EEG showed that the wave patterns in the epileptic group were spike or sharp waves and the amplitudes were largest [(190.570±23.590) μV]. Compared with the epileptic group, amplitudes were reduced ( P<0.001) in the H 2S donor+epileptic group. PKG mRNA and PKG protein were expressed differently among all groups (PKG mRNA: n=5, H=26.714, P<0.001; PKG protein: n=5, F=30.597, P<0.001). Compared with the control group, the expression of both PKG mRNA and PKG protein was decreased (PKG mRNA: 1.000±0.001 vs 0.782±0.064, P=0.023; PKG protein: 0.550±0.037 vs 0.145±0.020, P=0.042) in the epileptic group. Besides, Kir6.2 mRNA and Kir6.2 protein were expressed differently among all groups (Kir6.2 mRNA: n=5, H=27.761, P<0.001; Kir6.2 protein: n=5, F=60.659, P<0.001). Compared with the control group, the expression of both Kir6.2 mRNA and Kir6.2 protein was decreased (Kir6.2 mRNA: 1.000±0.001 vs 0.897±0.033, P=0.004; Kir6.2 protein: 0.384±0.035 vs 0.215±0.016, P=0.024) in the epileptic group. And the concentrations of cGMP and p-PKG were decreased (cGMP: P<0.001; p-PKG: P<0.001) in the epileptic group. The results in the H 2S donor+epileptic group were up-regulated (PKG mRNA: P=0.047; PKG protein: P<0.001; Kir6.2 mRNA: P=0.011; Kir6.2 protein: P<0.001; cGMP: P<0.001; p-PKG: P<0.001) compared with the epileptic group. However, the results in the KT5823+H 2S donor+epileptic group were down-regulated (PKG mRNA: P=0.015; PKG protein: P=0.027; Kir6.2 mRNA: P=0.013; Kir6.2 protein: P=0.017; cGMP: P=0.005; p-PKG: P<0.001) compared with the H 2S donor+epileptic group. Conclusion:A possible mechanism is that H 2S prevents the epileptic seizure from modulating the subunit Kir6.2 of ATP sensitive potassium channels via the cGMP/PKG signaling pathway.

Objective To evaluate the cancer risk among the inhabitants around a certain nuclear facility of Gansu Province after operation for nearly 50 years.Methods Specially developed forms were filled by countryside doctors in the villages 30 km on the leeward or at the lower reaches of Yumen City,Gansu Province where a nuclear facility had operated for nearly 50 years,to register the relevant data of those who died of solid cancer and leukemia during the period from 1 January 2004 to 31 December 2008 based on the relevant data and household survey.A town 90 km away from the nuclear facility with 4181 people were regarded as control area.Results The crude mortality and standardized mortality rate(SMR) of cancer were 95.51×10-5 and 93.56×10-5.respectively.The crude mortality and SMR of leukemia were 2.44×10-05 and 2.22×10-05, respectively.and the crude mortality and SMR of cancer were 106.88×10-05, and 89.31×10-5, respectively.The crude mortality and SMR of leukemia were 2.44×10-05 and 2.22×10-5, respectively in the investigated area,and the crude mortality of leukemia was 3.56×10-5 (only one leukemia cage died)in the control area in the same time.The cancer and leukemia mortality rates of the investigated area were similar to those of control area.Conclusions Nuclear facility does not significantly increase the cancer mortality among the residents living nearby.

Objective : To evaluate the immune effects of inactivated H7N9 influenza vaccine. Methods : We searched several common databases（The Cochrane Library,PubMed,China Biology Medicine disc,China National Knowledge Infrastructure,etc.）for research articles about immune effects of H7N9 influenza vaccine published from the time the database built to July 10th of 2018,using H7N9 and vaccine as keywords. After screening the articles according to the inclusion and exclusion criteria,we assessed the quality of the studies and then employed seroconversion rate（SCR）as an outcome indicator to analyze the immune effects of different doses and adjuvants. Results : We recruited 5 articles on inactivated H7N9 influenza vaccine from 1 679 articles. The sample size was 2 579. The results of the meta-analysis showed that the rate difference（RD）values of SCR in each dose group after the first dose ranged from 1% to 10%,which indicated a poor protective effect;after the second dose of immunization,the RD values of SCR in the vaccines without adjuvants ranged from 13% to 19%,which was not effective enough;the RD values of SCR in the vaccines with adjuvants ranged from 62% to 69%,which met the licensing criteria for influenza vaccine;better results could be achieved when immunized with two doses of vaccines with adjuvants（ RR=1.19,95%CI：1.02-1.39）;vaccines with AS03 or MF59 at the lowest dose of 3.75 μg had the same immune effects as ones at a dose of 15 μg;vaccines with AS03（RD=89%,95%CI：85%-93%）were superior to those with MF59（RD=42%,95%CI：9%- 75%）. Conclusion Inactivated H7N9 influenza vaccines could achieve good immune effects when inoculated two doses with adjuvants,and the minimum effective dose was 3.75 μg.

Objective To understand the correlation of expression levels of serum stromal cell-derived factor 1α (SDF-1α), osteoprotegerin (OPG) and β2microglobulin (β2-MG) in patients with multiple myeloma (MM) with or without myeloma bone disease (MBD). Methods Eighty patients with MM who were admitted to the Affiliated Hospital of Inner Mongolia Medical University from January 2014 to June 2017 were selected; all of the patients met the international diagnostic criteria for MM. According to the symptoms such as bone pain, the patients were divided into group with MBD (45 cases) and group without MBD (35 cases). Enzyme-linked immunosorbent assay (ELISA) was used to detect the serum levels of SDF-1α and OPG, and radioimmunoassay was used to detect the expression of MM major prognostic indicator β2-MG. The MBD score was evaluated in 45 patients selected by random number table after sacroiliac joint X-ray and three-dimensional bone reconstruction. The χ 2test was used to compare the categorical variables; the two independent sample t-test was used to compare the continuous variables that conformed to the normal distribution between two groups, and the Pearson method was used for the correlation analysis. Results The expression level of serum SDF-1α in the group with MBD was significantly higher than that in the group without MBD [0.31±0.17) pg/ml vs. (0.18±0.06) pg/ml], and the difference was statistically significant (t ＝-4.21, P < 0.001). The expression level of serum OPG in the group with MBD was significantly lower than that in the group without MBD [(0.73±0.50) pg/ml vs. (1.08±0.31) pg/ml], and the difference was statistically significant (t＝ 3.62, P< 0.001). Pearson analysis showed that β2-MG level in the group was positively correlated with SDF-1α level (r＝ 0.84, P< 0.001), and negatively correlated with OPG level (r＝ -0.48, P<0.001). The β2-MG level in the group without MBD did not show a correlation with the SDF-1α and OPG levels. Conclusions In the serum of patients with MBD, the expression levels of β2-MG and SDF-1α are increased, and the expression level of OPG is decreased. SDF-1α and OPG may be new clinical biochemical indicators for diagnosis, treatment and prognosis assessment in MBD.

Objective:To investigate the implementation procedures and dosimetric verification of the first patient treated with total body irradiation (TBI) based on volumetric modulated arc therapy (VMAT).Methods:Two sets of CT images were acquired under the head-in first and foot-in first to contour the planning target volume (PTV) of the cranial and caudal segments to accomplish the treatment of the whole body length, on which two interrelated plans of 5 subsequent isocenters with a total of 15 VMAT fields were performed to cover all PTVs. The plans were prescribed to ensure 90% PTV dose coverage with a total dose of 12 Gy in 6 fractions. Firstly, a dose optimization was performed on the caudal CT images, then the cranial CT images were optimized based on the dose distribution of the caudal CT images. The evaluation of the final treatment plan was carried out based on a plan sum of both two sets of images. The parameters of PTV and organs at risk (OARs) were measured by dose volume histograms from the accumulated plan. The quality assurance comprised the verification of the VMAT plans for each individual isocenter via Delta4 phantom. The dose distribution in the overlapped region between two adjacent central fields was verified with EBT3 film. The absolute dose at the overlapped region between two images was measured via Pinpoint chamber. In vivo dosimetry on the patient′s skin was monitored by MOSFET dosimeters. The results of planning parameters and treatment duration were analyzed. Results:The mean doses of two segments of PTVs were 12.45 Gy and 12.37 Gy. The mean dose for the lung was 10.8 Gy. The machine unit (MU) and mean treatment delivery time were 2 883 MU and 24.3 min, and the mean total time per fraction was 121 min. The mean 3%/3 mmγ-analysis pass rate for each isocenter VMAT plan was (99.74±0.42)%, and the mean 5%/5 mmγ-analysis pass rate for the overlapped region was (90.11±2.72)%. The average deviation of absolute dose in the overlap region of the caudal and cranial images was (3.6±0.4)%. In vivo measurement of 8 points on the patient showed that the dose of each region was ranged from 1.57 Gy to 2.04 Gy. Conclusion:According to the results of dosimetric verification, TBI based on multi-isocenter VMAT can be applied in clinical practice, which remains to be improved in terms of dose distribution, measurement results and clinical efficiency.