Objective? To observe the effects of continuous quality improvement on the incidence rate of ventilator-associated pneumonia (VAP) in intensive care unit (ICU). Methods? Totally 158 patients using ventilators in ICU of Hangzhou Red Cross Hospital between January and June 2016 were selected as the control group using convenient sampling, and another 165 patients using ventilators between January and June 2017 were selected as the observation group. Patients in the control group received conventional nursing care, while patients in the observation group received Plan-Do-Check-Act (PDCA) Cycle Management with the quality of standardized nursing process, standardized upper respiratory tract management and hand hygiene continuously improved. Incidence rate of ventilator-associated pneumonia(VAP), rate of pass in oral nursing care and hand hygiene compliance in medical and nursing workers were compared between the two groups before and after improvement. SPSS 17.0 was used for statistical analysis. Results? The incidence rate of VAP during the first half of 2017 totaled 5.07‰, a decrease of 6.42‰ compared with the first half of 2016. There was statistically significant difference in the incidence rate of VAP between the two groups (P＜0.01); the rate of pass in oral nursing care after improvement (93.17%) was statistically higher than that before improvement (57.31%) (P＜ 0.01); and the hand hygiene compliance after improvement (93.67%) was statistically higher than that before improvement (67.33%) (P＜ 0.01). Conclusions? Continuous quality improvement can reduce the incidence rate of VAP in ICU, which is operable and worth promoting in clinical practice.

Purpose To explore the clinical value of iodine content and energy spectrum in dual-source dual-energy CT scan in the diagnosis of inflammatory bowel disease reactive hyperplasia lymph nodes (LNs) and metastatic LNs in patients with colorectal cancer.Materials and Methods Complete dual energy scanning data of 51 reactive LNs in 30 patients with inflammatory bowel disease (15 cases of ulcerative colitis,15 cases of Crohn's disease) and 35 metastatic LNs in 20 patients with colorectal cancer confirmed by colonoscopy or pathology were collected and retrospectively analyzed.The iodine contents of reactive hyperplasia LNs and metastatic LNs were detected and the slopes of energy spectrum curves were compared between the two different pathological LNs.Moreover,the receiver operating characteristic curve was applied to determine the optimum sensitivity and specificity of differential diagnosis of these two kinds of LNs.Results The iodine contents of inflammatory bowel disease reactive hyperplasia LNs and metastatic LNs in patients with colorectal cancer in arterial phase were (2.66±0.70) mg/ml and (1.65± 0.81) mg/ml,and the slopes of curves were 2.81 ±0.56 and 0.14±0.09,respectively.There were significant differences in the iodine contents and the slopes of the energy spectral curves between these two kinds of LNs in arterial phase (P＜0.05).Moreover,the diagnostic efficacy of energy spectrum curve slope,of which the sensitivity,specificity and area under the curve was 96.7％,76.7％ and 0.846,respectively;was higher than those of iodine content in diagnosing inflammatory bowel disease reactive hyperplasia LNs and metastatic LNs.Conclusion Dual-source dual-energy CT-derived arterial phase measurement of iodine content and slope of energy spectral curve has certain significance for differential diagnosis of inflammatory bowel disease reactive hyperplasia LNs and metastatic LNs,and the slope of spectral curve is superior to iodine.

Purpose To explore the feasibility of dual source CT virtual unenhanced replacing conventional plain scan in parotid gland mass examination.Materials and Methods Thirty-five parotid gland mass (38 focus) confirmed through dual source CT and surgical operative pathology in the First Affiliated Hospital of Kunming Medical University were retrospectively analyzed,including 13 pleomorphic adenoma parotid,14 adenolymphoma (17 focus),5 malignant tumor and 3 inflammatory lesions.All patients received conventional plain scan and dual energy enhanced scan.Liver virtual unenhanced software was adopted to obtain virtual unenhanced image in arterial phase and concordance of parotid gland mass displayed on conventional plain scan and virtual unenhanced images was compared.Normal parotid tissue,focal area,salivary gland,thoracic paraspinal muscle,average CT value of lower jawbone,signal noise ratio noise ratio (SNR),contrast noise ratio noise ratio (CNR),image quality score,radiation dose and effective dose (ED) for conventional plain and virtual unenhanced were compared.Results Subjective image quality score for conventional plain scan and virtual unenhanced was 4.34 ± 0.80 and 4.17 ± 0.82,respectively;and difference between the two was of no statistical significance (P＞0.05).Average CT value difference of angulus mandibulae thoracic paraspinal muscle,submandibular gland and normal parotid for 35 patients with parotid space-occupying lesions with conventional plain scan and virtual plain scan was of no statistical difference (P＞0.05).The average CT value of conventional plain scan parotid mass and mandible compared with the virtual plain scan,the difference was statistically significant (P＜0.05).SNR difference for parotid gland mass was of statistical significance (P＜0.05).Difference of CNR between the two groups was of no statistical significance (P＞0.05).ED of virtual plain scan was lower than that of conventional plain scan and the difference was of statistical significance (P＜0.05).The reduced radiation dose was about 38.6％.Conclusion Conventional plain scan and virtual unenhanced are of highly concordance in examination and diagnosis of parotid gland mass and radiation dose for virtual unenhanced is less.

Objective:To construct a surface display system containing various lengths of the Ag43 passenger domain for an optimal bacterial surface display of foreign protein HPV16L1.Methods:(1) Ag43 gene sequences of different lengths were inserted into pET22b vector to construct four Ag43 surface display vectors (Ag43/138, Ag43/551, Ag43/552 and Ag43/700) using PCR and subcloning strategy. (2) The generation of four HPV16L1-Ag43 fusion constructs was completed by PCR and subcloning methods. (3) HPV16L1-Ag43 fusion proteins were expressed and analyzed by SDS-PAGE. (4) The surface exposure of HPV-16L1 was verified using trypsin digestion.Results:PCR analysis and sequencing results showed that Ag43 surface display vectors and HPV16L1-Ag43 fusions were constructed successfully. SDS-PAGE showed that the expression of HPV16L1-Ag43 fusion proteins could be induced with 0.2 mmol/L IPTG and the protein content was reduced after the cells were treated with trypsin, especially the content of Ag43/700-HPV16L1 that showed a drastic reduction.Conclusions:The Ag43 surface display system was successfully constructed and could be used for a successful display of HPV16L1. This study also showed that Ag43/700 comprising only the α-helix and the β-barrel of Ag43 provided an optimal surface display for HPV16L1.

Objective:To construct an in vitro reconstitution system for inverse autotransporters in order to further investigate their translocation mechanism. Methods:Intimin from Escherichi coli was used as a model substrate. Spheroplasts were prepared from Escherichi coli strains overexpressing Intimin to induce the expression of Intimin. Recombinant β-barrel assembly machinery (BAM) complex was obtained and purified, and then proteoliposomes containing BAM were prepared. Following the digestion with proteinase K, the translocation was detected by SDS-PAGE. Results:Spheroplasts were induced to express Intimin, and then BAM-containing proteoliposomes were added to the system. Compared with control and liposomes groups, the experimental group showed that Intimin was resistant to proteinase K treatment, indicating that Intimin was successfully translocated.Conclusions:The translocation of Intimin required the participation of BAM complex. An in vitro reconstitution system for inverse autotransporters was constructed in this study, providing a method to study the translocation mechanism of inverse autotransporters.

Objective:To screen active antibacterial components from licorice extract using BamA and BamD, the core components of Escherichia coli ( E. coli) β-barrel assembly machinery (BAM), as targets in order to combat the increasingly serious problem of antibiotic resistance. Methods:Affinity ultrafiltration combined with high performance liquid chromatography-mass spectrometry (HPLC-MS) was used to screen the potential components interacting with BamA and BamD from licorice extract. Changes in the expression of bamA and bamD genes of E. coli after treatment with the compounds were detected by fluorescence quantitative PCR, and the effects of the compounds on the function of the BAM complex to integrate outer membrane proteins into the bacterial outer membrane were analyzed using an in vitro recombination system. The influence of the compounds on the integrity of bacterial membranes was evaluated through analyzing the accumulation of SDS within the bacterial cells. Results:Bioaffinity ultrafiltration combined with HPLC-MS screening revealed that 18β-glycyrrhetinic acid could interact with BamD. After 18β-glycyrrhetinic acid treatment, the expression of bamA gene increased by 1.5 times, and the expression of bamD gene increased by 2 times. However, the inhibitory effect of 18β-glycyrrhetinic acid on the membrane insertion function of the BAM complex was not observed in the in vitro recombinant system assay, and the cell membrane integrity assay experiments did not reveal any disruption of the E. coli cell membrane by 18β-glycyrrhetinic acid. Conclusions:Using BamA and BamD proteins as targets, a natural product screening method using affinity ultrafiltration combined with HPLC-MS is established. The screening result shows that 18β-glycyrrhetinic acid can interact with BamD and affect the expression of outer membrane proteins in E. coli. Therefore, the screening and experimental procedures established in this study are of good reference value for the screening of novel antimicrobial drugs from other sources targeting outer membrane proteins, and this study also suggests that the selection of the relevant target sites is crucial for the successful screening of the corresponding natural products.