OBJECTIVE To understand the related factors,the situation and dynamics of hospital infection in order to effectively prevent and control it.METHODS From 12306 cases of inpatients who had investigated retrospectively,706 cases were with nosocomial infection monitored from Jan to Dec 2006.RESULTS The hospital infection rate was 5.74% in 2006.The hematological disease and,cancer patients and the elderly,were the high-risk population.The main infection site was the respiratory tract.Fungi accounted for 21.35%,the top was the Candida albicans.CONCLUSIONS To strengthen the training of medical staff,to monitor the key departments of hematology and cancer and respiratory diseases and to attend the disease surveillance and rationally use of antibiotics are the effective measures to reduce hospital-acquired infections.

BACKGROUND:Shear stress can directly mediate the expression of endothelial cells, especially some cytokine genes whose codes are related to angiogenesis. Otherwise, flow shear stress of blood plays an importantly biological role in regulating vascular structure and function.OBJECTIVE: To observe the effects of laminar flow shear stress on the proliferation of vascular endothelial cells and the expression of protooncogene c-myc in human cerebral arteriovenous malformation.DESIGN: Randomized controlled study.SETTING: Department of Neurosurgery, Shenyang General Hospital of Military Area Command of Chinese PLA.MATERIALS: The experiment was carried out in the Neuromedical Institute, General Hospital of Shenyang Military Area Command of Chinese PLA from November 2006 to February 2007. Fresh samples of human cerebral arteriovenous malformation were derived from 20 patients who were of grade Spetzler Ⅱ -Ⅲ and received resection of human cerebral arteriovenous malformation in the Department of Neurosurgery, General Hospital of Shenyang Military Area Command of Chinese PLA in 2006. All cases were diagnosed with whole-brain angiography before operation. The main reagents and equipments were detailed as follows: M199 culture media (Gilbco BRL), quality fetal bovine serum (HyClone), endothelial cell growth supplement (ECGS; Sigma, USA), CO2 incubator (Forma Scientific, USA), flow cytometry analysis of cell cycle kit (BD Company), flow cytometer (FACS Calibur, BD Company), rat-anti-human c-myc monoclonal antibody (Santa Cruz Company, USA), and reverse transcription polymerase chain reaction (RT-PCR) kit (Promega).METHODS: Tissue explants adherent method was used to culture vascular endothelial cells of human cerebral arteriovenous malformation, and then the cells were classified into 4 groups based on degree of shear stress, including control group, low shear stress group, moderate shear stress group and high shear stress group. Cultured endothelial cells of human cerebral arteriovenous malformation were put in a parallel plate flow chamber. In addition, cells in the low,moderate and high shear stress groups were stressed by low, moderate and high shear stress for 8 hours, respectively.However, shear stress in the control group was 0 Pa. Flow cytometry was used to measure proliferation index, and the expression of c-myc protein and c-myc mRNA were determined by immnocytochemistry and RT-PCR analysis respectively.MAIN OUTCOME MEASURES: Expressions of c-myc protein and c-myc mRNA and proliferation index in endothelial cells under various degrees of shear stress.RESULTS: ① Proliferation index: Proliferation index was higher in the moderate and high shear stress groups than that in the control group (P ＜ 0.05, 0.01). ② Expression of c-myc protein: Immuneposjtjve expression of c-myc protein was gradually increased with the increase of shear stress and there were significant differences in the three shear stress groups as compared with control group (P ＜ 0.05-0.01). ③ Expression of c-myc mRNA: Proliferation index of endothelial cells was higher in the low and moderate shear stress groups than that in the control group (P ＜ 0.05).CONCLUSION: Flow shear stress can induce expression of c-myc and activate expression of c-myc gene based on gene transcription so as to promote the proliferation of vascular endothelial cells in human cerebral arteriovenous malformation

BACKGROUND:Antisense gene therapy offers immense promise for the management of human cerebral arteriovenous malformation through inhibiting expression of vascular endothelial growth factor and angiogenesis in endothelial cells.OBJECTIVE: To observe the inhibitory effect of vascular endothelial growth factor-antisense oligonucleotide (VEGF-ASODN) on the proliferation of vascular endothelial cells in human cerebral arteriovenous malformation.DESIGN: Observational contrast study.SETTING: Department of Neurosurgery, General Hospital of Shenyang Military Area Command of Chinese PLA.MATERIALS: The experiment was carried out in the Neuromedical Institute, General Hospital of Shenyang Military Area Command of Chinese PLA from August to December 2006. A total of 18 patients with human cerebral arteriovenous malformation were selected from Department of Neurosurgery, Shenyang General Hospital of Military Area Command of Chinese PLA. There were 12 males and 6 females and their mean age was 40 years. Cerebral arteriovenous malformation was classified based on Spetzler grade: grade Ⅱ (n =10) and grade Ⅲ (n=8). All cases were diagnosed with whole cerebral angiography before operation and they provided the confirmed consent. Main reagents were detailed as follows: endothelial cell growth supplements (ECGS, Sigma, USA), 391 DNA automatic synthetic device (Shanghai Shenggong Liyong Company, PE, USA), anaerobic incubator (DY-1, Zhejiang), human vascular endothelial growth factor enzyme-linked kit (TBD Company, Beijing), 96E enzyme-labeling device (ERMA, INC), cell cycle analytical reagent kit (BD Company), and flow cytometer (FACS Calibur, BD Company).METHODS: ①Experimental procedure: Tissue explants adherent method was used to culture vascular endothelial cells from human cerebral arteriovenous malformation. The third generated cells were used and randomly divided into antisense group, sense group and control group with four bottles of cells in each group. Sense and antisense phosphorothioate oligodeoxynucleotides of artificial vascular endothelial growth factor selected from the antisense group and the sense group were covered with positive liposomes, and then they were used to transfected vascular endothelial cells cultured from human cerebral arteriovenous malformation; however, cells in the control group were not dealt with any treatments. Cells in the three groups were incubated in anaerobic incubator (including 0.95 volume fraction of N2 and 0.05 volume fraction of CO2) at 37 ℃ for 2, 4 and 8 hours, respectively. ② Experimental evaluation: Cell cycles were measured, protein content of vascular endothelial growth factor was measured, and mRNA expression of vascular endothelial growth factor was also detected.MAIN OUTCOME MEASURES: Expression of mRNA and protein of vascular endothelial growth factor and proliferation exponent at different times of hypoxia.RESULTS: ①mRNA expression of vascular endothelial growth factor: At 2, 4 and 8 hours after hypoxia, mRNA expression of vascular endothelial growth factor was higher than that before hypoxia in the control group (P ＜ 0.05);however, mRNA expression was lower in the antisense group than that in the control group (P ＜ 0.05). ② Protein content of vascular endothelial growth factor: At 2, 4 and 8 hours after hypoxia, protein content of vascular endothelial growth factor was higher than that before hypoxia in the control group (P ＜ 0.05); however, protein content was lower in the antisense group than that in the control group (P ＜ 0.05). ③ Proliferation exponent: At 4 and 8 hours after hypoxia,proliferation exponent of endothelial cells cultured from human cerebral arteriovenous malformation was higher than that before hypoxia in the control group (P ＜ 0.05); however, proliferation exponent was lower in the antisense group than that in the control group (P ＜ 0.05).CONCLUSION: Hypoxia may induce gene expression of vascular endothelial growth factor in endothelial cells at the transcriptional level. Antisense vascular endothelial growth factor can obviously inhibit gene expression of vascular endothelial growth factor cultured from human cerebral arteriovenous malformation and proliferation under hypoxic conditions.

OBJECTIVE To find the infla mmation bio markers induced by coke oven e missions (COE),we investigated the changes of T helper 17 (Th17 )cytokines in hu man bronchial epithelial (16HBE)cells.METHODS 16HBE cells were exposed to organic extracts of COE collected fro m co-king plant at the concentrations of 5,10 and 20 mg·L -1 for 24 h or 5 d to establish short-term and long-term cell models,respectively.Cell viability was measured by MTT assay and infla mmatory da mage was assessed by lactate dehydrogenase assay (LDH).The cytokines in culture supernatant sa mples was detected by co mmercial hu man Th17 cytokine panel kit.RESULTS COE Can induce infla mmation in COE 20 mg·L -1 group and no expression on IL-17 F and IL-1 β.The concentration of IL-10 was 1 .25 ± 0.54,1 .39 ±0.13 and (1 .90 ±0.73)pg·mL -1 in COE 5,10 and 20 mg·L -1 group showing good con-centration-effect relationship (r=0.98,P <0.05 ).IL-23 expression was found only higher at 10 and 20 mg·L -1 and the concentrations were 3.38 ±3.90 and (1 .74 ±2.00 )pg·mL -1 ,respectively.In 16HBE cells treated by COE for 5 d,elevated expression of IL-17A was found in COE 5 and 10 mg·L -1 group,and there was statistically sigificant difference between COE 10 mg·L -1 and DMSO group (P<0.05).Elevated concentration of IL-17F of 10.2 ±1 1 .78 and (6.79 ±7.84)pg·mL -1 was found in COE 5 and 10 mg·L -1 group.The concentration of IL-10 was 1 .71 ±0.02,1 .49 ±0.25 and (2.82 ± 0.33)pg·mL -1 in COE 5,10 and 20 mg·L -1 group,respectively.We found increased IL-1 βexpression with concentration of 2.72 ±0.62,2.25 ±0.33 and (0.93 ±0.21 )pg·mL -1 in COE 5,10 and 20 mg·L -1 group with negative dose-response relationship.We also found more elevated TNF-αlevels in the 5 d than in the 24 h model with no COE specific relationship.CONCLUSION COE induces expression changes of Th17 cytokines profile in 16HBE cells,including IL-23 and IL-1 βfor early and long-term infla mmation,respectively.IL-10 may be a candidate marker for population study on COE induced infla mmatory injury.

Objective:To prepare a progressive gradient-aperture scaffold composed of silk fibroin(SF)-chitosan(CS)-nano-hydroxyapatite(nHAp)for osteochondral repair.Method:The SF solution, CS solution and nHA suspension were mixed in vitro at equal proportions.The progressive gradient osteochondral(OC)scaffold-1(2%), scaffold-2(3%)and scaffold-3(4%)was respectively prepared by using centrifugation, vacuum freeze-drying, chemical cross-linking and three shaping steps.General conditions, porosity, hot water dissolution rate, water swelling rate, compression water swelling rate, water swelling rate after dissolution, mechanical properties, internal structure observation and pore size were measured.Rat bone marrow mesenchymal stem cells(BMSCs)were cultured and the scaffold extract was prepared.The effect of scaffold extract on the proliferation of BMSCs was detected by the cell counting kit-8(CCK-8)method.BMSCs were co-cultured with the scaffold, and the distribution and morphology of the cells around the scaffold were observed.Results:The structure of scaffold was regular in each group and the porosity was more than 80%.Along with the increase of the material concentration, the water swelling rate of the scaffold was decreased gradually( P<0.05). Compared with before compression, the water swelling rate of scaffold-1 was decreased after compression( P<0.05). There was no significant difference in the hot water dissolution rate among all groups( all P>0.05), and the complete dissolution of the scaffold-1, scaffold-2 and scaffold-3 in vitro required 65.9, 60.9, and 73.9weeks, respectively.The elastic modulus of scaffolds in above three groups were 0.0955, 0.1762 and 0.3468 MPa, respectively.The examination results of scanning electron microscope(SEM)showed that the internal structure of scaffold was honeycomb in each group, the pore shape was regular, which showed an inter-connected pore network.The pore distribution was gradually dense and the pore diameter gradually decreased from the cartilage side to the osteogenic side( P<0.05), and the nHAp content increased gradually.The scaffold extract had no obvious toxicity to the growth and proliferation of BMSCs in each group.After BMSCs were seeded on scaffolds and co-cultured for 5 days, the cells grew well without obvious cell death or morphological abnormalities. Conclusions:In this study, a progressive gradient pore size OC scaffold is successfully prepared with good physical properties and biocompatibility, which is expected to be a new bio-mimetic composite scaffold material for repairing OC defects.

Objective To investigate the identification of octreotide(OCT)modified chitosan(CS)miR-155 molecular beacon nanoparticles(CS-miR-155-MB-OCT)and imaging of lung cancer cells for the early screening of lung cancer.Methods A nude mouse model of lung transplantation tumor was established by injecting A549 lung cancer cells into tail veins to establish lung xenograft models.Cre adenovirus was injected through nasal cavity,and mice were killed at 4,6,8 and 12 weeks after adenovirus injection to establish lung cancer models of atypical hyperplasia,adenoma,carcinoma in situ and adenocarcinoma of lung in LSL K-ras G12D transgenic mice at different pathological stages.Lung tissue samples were taken and observed by HE staining.Immunohistochemistry were used to detect the expression of somatostatin receptor 2(SSTR2).Real-time fluorescence quantitative PCR was used to detect miR-155 expression levels in lung xenograft models and transgenic mice at different stages of lung cancer.Then CS-miR-155-MB and CS-miR-155-MB-OCT were injected via tail vein in lung xenograft models.CS-miR-155-MB-OCT was injected via tail vein in transgenic mice models.The fluorescence signals of lung in nude mice and transgenic mice at different disease stages were imaged by living imaging system.Frozen slices of lung tissue were made.The source of fluorescence signal was detected by laser confocal scanning microscope(CLSM).Results HE staining showed that lung transplantation tumor models and lung cancer models of atypical hyperplasia,adenoma,carcinoma in situ and lung adenocarcinoma at different pathological stages were successfully constructed.Immunohistochemical analysis showed somatostatin receptor 2(SSTR2)was expressed in transplanted lung tumor and tissue at different pathological stages.In transgenic mouse models,the expression of miR-155 was gradually increased as the disease progressed(P＜0.05).In lung xenograft models,the fluorescence signals were significantly higher in the CS-miR-155-MB-OCT group than those of the CS-miR-155-MB group(P＜0.05).In transgenic mouse models,the fluorescence signals gradually increased with the gradual progression of lesions(P＜0.05).After re-imaging the lung tissue,it was found that the fluorescence signal came from lung,and CLSM showed that the fluorescence signal came from cancer cells and some normal alveolar epithelial cells.Conclusion CS-miR-155-MB-OCT can dynamically reflect the occurrence and development of lung cancer according to changes of different fluorescence intensity,thus providing a new technology for the early diagnosis of lung cancer.

Objective:To explore the application effect of micro-video combined with scenario simulation teaching in the training of orthopedic surgery posture placement for intern nursing students, so as to lay a foundation for improving the operation skills of nursing interns.Methods:A total of 86 nursing students in the operating room of Xijing Hospital of Air Force Military Medical University from June 2019 to June 2020 were selected as the research objects. They were divided into the control group ( n=42) and the intervention group ( n=44) according to the time of enrollment. The control group adopted the traditional clinical teaching and learning method, while the intervention group adopted the micro-video combined with scenario simulation teaching method. The effect of intervention was evaluated by theoretical assessment scores, skill operation assessment scores, medical education environmental scores and two-way teaching satisfaction. Results:The theoretical and technical performance assessment scores of the intervention group were higher than those of the control group ( P<0.05) . In addition, the correct rate of surgical positioning in the intervention group increased, while the time required to complete the positioning was reduced ( P<0.05) . In terms of medical education environment scores, students' perception of learning, students' perception of teachers, students' perception of the environment, and students' social self-perception scores and total scores of the intervention group were all higher than those of the control group ( P<0.05) . However, there was no statistically significant difference in academic self-perception of students between the two groups ( P>0.05) . At the same time, the two-way teaching satisfaction of nursing students and teachers in the intervention group was improved ( P<0.05) . Conclusions:The application of micro-video combined with scenario simulation teaching in the training of orthopedic surgical position placement of intern nursing students can effectively improve the teaching quality.

Objective To investigate distribution and antimicrobial resistance among nosocomial pathogens from 13 teaching hospitals in China in 2009. Methods Non-repetitive pathogens from nosocomial BSI, HAP and IAI were collected and sent to the central lab for MIC determination by agar dilution method.WHONET5.6 software was used to analyze the data. Results A total of 2 502 clinical isolates were collected. The top three pathogens of BSI were Escherichia coli [27. 1% (285/1 052 )] , coagulase-negutive staphylococcus [12. 6% ( 133/1 052)] and Klebsiella pneumoniae [10. 8% ( 114/1 052)]. The top three pathogens of HAP were Acinetobacter baumannii [28. 8% (226/785)], Pseudomonas aeruginosa [16. 1% (126/785)] and Klebsiella pneumoniae [14.6% (115/785 )] . The top three pathogens of IAI were Escherichia coli[31.0% ( 206/665 )], Klebsiella pneumonia [11.3% ( 75/665 )] and Enterococcus faecium [10. 8% (72/665)]. Against Escherichia coil and Klebsiella spp. , the antimicrobial agents with higher than 80% susceptibility rate included imipenem and meropenem (98. 1%-100% ), tigecycline (95.3%-100% ), piperacillin-tazobactam ( 88.6% -97. 1% ) and amikacin ( 88. 3% -92. 5% ). Against Enterobacter spp. , Citrobacter spp. and Serratia spp. , the susceptibility rates of tigecycline were 93.5% -100% whereas the value of imipenem and meropenem were 92.9% -100%. Other antimicrobial agents with high activity included amikacin ( 85.2% -96. 7% ), pipcracillin-tazobactam ( 82.4% -96.4% ), cefepime ( 79. 6% -96. 7% ) and cefoperazonc-sulbactam (78. 7%-90. 0% ). Polymyxin B showed the highest susceptibility rateagainst Pseudomonas aeruginosa ( 100% ), followed by amikacin ( 81.9% ) and piperacillin-tazobactam (80.1% ). Polymyxin B also showed the highest susceptibility rate against Acinetobacter baumannii (98. 8% ), followed by tigecycline (90. 1% ) and minocycline (72. 0% ). The incidence of carbapenemresistant Acinetobacter baumannii was 60. 1%. The MRSA rate was 60. 2% and the MRSCoN rate was 84. 2%. All Staphylococcus strains were susceptible to tigecycline, vancomycin, teicoplanin and linezolid except for one isolate of Staphylococcus haemolysis with intermediate to teicoplanin. Two Enterococcus faecalis isolates which were intermediate to linezolid and one Enterococcus faecium isolate which was resistant to vancomycin and teicoplanin was found in this surveillance, while the MICs of tigecycline against these three isolates were 0. 032-0. 064 μg/ml. Conclusions Tigecycline, carbapenems, piperacillin-tazobactam,amikacin and cefepime remain relatively high activity against nosocomial Enterobacteriaceae. Pseudomonas aeruginosa exhibite high susceptibility to polymyxin B, while Acinetobacter baumanni shows high susceptibility to polymyxin B and tigecycline. Tigecycline, vancomycin, teicoplanin and linezolid remain high activity against nosocomial gram-positive cocci.

Objective To investigate antimicrobial resistance among Streptococcus pneumoniae clinically isolated from 14 teaching hospitals located at different areas in China in 2005-2008 and to give logical guidance for clinical empirical therapy.Methods A total of 1 317 non-repetitive S.pneumoniae isolates in 14 teaching hospitals from 2005-2008 were collected and sent to the central lab for reidentification and susceptibility testing, including 271 isolates collected in 2005, 391 isolates collected in 2006, 363 isolates collected in 2007 and 292 isolates collected in 2008. Most of the isolates were from community-acquired respiratory tract infections, which were isolated from outpatient or emergency department patients with respiratory tract infections or those patients with respiratory tract infections within ≤48 hours hospitalization.The districts where the organisms were isolated include North China, Northeast China, South China, Central and Northwest China and East China.The patients included adults, teenagers and children.The minimum inhibitory concentrations (MICs) or inhibitory zone diameter of 17 antimicrobial agents were determined by Etest method, agar dilution method or disk diffusion method.WHONET5.5 software was used to analyze susceptibility rate, intermediate rate, resistance rate, MIC50 and MIC90.Results Linezolid (100%) and fluoroquinolones (95.2%-99.7%) showed excellent activities against S.pneumoniae.Among β-lactams, amoxicillin-clavulanic acid remained high activities (73.8%-92.1%),followed by penicillin, ceftriaxone and cefepime with year-over-year decrease in activities.The activities of three second-generation cephalosporins were low (36.3%-38.4% in 2008).The activities of erythromycin, azithromycin, clindamycin, trimethoprim/sulfamethoxazole and tetracycline against S.pneumoniae were poor and decreased year over year.The incidence of penicillin non-susceptible S.pneumoniae (PNSP) was increasing especially for PISP (from 4.4% in 2005 to 20.2% in 2008).The incidence of PNSP in North China was low (6.0%), while this value were high in central China and East China (30.1% and 38.7%, separately).The incidence of PNSP in adults (15.7%) was obviously lower than that in children(≤5 years:33.0%) and teenagers (6-17 years:38.2%).Conclusions linezolid and fluoroquinolones showed excellent in vitro activity against S.pneumoniae, followed by penicillin and cephalosporins with year-over-year decrease of activity. Clinicians should pay more attention when using those antimicrobial agents with poor activity against S.pneumoniae, which include macrolides, clindamycin, trimethoprim/sulfamethoxazole and tetracycline.