Objective To understand the incidence.mortality and risk factors of ventilator -associated pneu-monia(VAP)in surgical intensive care unit among elderly patient,in order to direct the clinical prevention and treat-ment of VAP.Methods Retrospective analysis was used on 65 cases of mechanical ventilation elderly patients in our hospital nearly 3 years.Results The incidence of VAP was 66.2%.The mortality of VAP was 67.4%.The factors of long-term mechanical ventilation,high APACHE Ⅱ score,low Glasgow score and inappropriate initial antimicrobial therapy were influenced the prognosis of VAP.Conclusion The incidence of VAP can be decreased and the cure rate can be increased by some effective measures in SICU.

Objective To establish a big animal model of secondary infection of acute necrotizing pancreatitis (ANP). Methods Thirty young pigs were allocated to experiment group ( n = 20 ) or control group (n = 10). The ANP model was induced by retrograde injection of a mixture solution of 5% sodium taurocholate and 5% trypsin (0. 5 ml/kg body weight) into the main pancreatic duct and ligation of the proximal end of the main pancreatic duct, and then the second step was injecting 3 ～ 4 ml living Escherichia coli (E coli) suspension (108/ml) to the necrotic area of the pancreas by fine needle aspiration technique under CT guidance in the experiment group, and by injecting 3 ～ 4 ml inactivated E coli in the control group using the same method. Multi-slice spiral CT dynamic enhanced scan was performed in both groups 1 day and 2 or 3 days after ANP modeling and 5 days after bacterial injection to calculate the CTSI score. Serum amylase, blood WBC count and blood bacterial culture was performed in both groups. 5 days later, the animals were scarified to observe the infected or necrosis foci, and perform smear, bacterial culture and pathologic examinations of the tissue around the infected or necrosis foci. Results The ANP secondary infection model was successfully established in 16 of the 20 animals in the study group, with a success rate of the 80.0% (16/20). There were 17 foci where the positive rate of bacterial culture was 100% (17/17 foci), and the success rate of blood bacterial culture was 68.8%(11/16). In the control group, the ANP model was established successfully in 7 of 10 animals (70%), except for one case of contamination, only one foci was identified;the positive rate of bacterial culture and the success rate of b|ood bacterial culture was 14.3% (1/7). Serum amylase and white blood WBC count increased with similar trends, WBC count in the study group was significantly higher than that in the control group (P<0.01). The mean CT severity index(CTSI) was all ≥4 in beth groups, indicating the severity was moderate to severe. Conclusions A stable and reliable model of secondary infection of ANP in big could be established satisfactorily by injecting active E. coli into the pancreatic necrosis tissue under CT guidance, which helps further pathogenic mechanism studies and clinical studies, especially imaging studies.

Objective To evaluate the feasibility of dopamine D2 receptor imaging agent (s)-(-)-N-(1-allylpyrrolidine-2-N-methyl)-5-(3-18F)-2,3-dimethoxy Benzamide (18F-Fallypride) for targeting islet cell imaging.Methods (1) Cytology experiment:Islet cells of 15×103 cells/well were incubated with 3.70 kBq/well 18F-Fallypride for 1 h and the uptake rate of cells was calculated (cell counts/(supernatant counts + cell counts)× 100％).Under the same experiment conditions,6 inhibiting groups were administrated with different concentration of dopamine inhibitors droperidol (1.0× 10-6,4.0× 10-6,2.0× 10-5,1.0× 10-4,5.0× 10-4 and 1.0× 10-3 mol/L,respectively).After 30 min,3.70 kBq of 18F-Fallypride was added to each inhibiting group,and the inhibiting rate was calculated.(2) Autoradiography:18 normal ICR mice were divided into 6 groups.For group A,ICR mice were injected with 18F-Fallypride (55 ± 5) MBq/mice through tail vein.For the other 5 inhibiting groups (group B-F),ICR mice were injected with different doses of droperidol (0.2,0.4,0.6,0.8 and 1.0 mg/kg,respectively),and after 30 min 18F-Fallypride were injected through tail vein.Ten minutes later,pancreas of ICR mice was taken for preparation of tissue section autoradiography.The data were analyzed by one-way analysis of variance and the least significant difference t test.Results (1) The 18F-Fallypride uptake rate of control group was (18.40± 1.21) ％.The uptake rates of inhibiting groups were (16.11±1.37)％,(15.76±0.99)％,(13.90±1.02)％,(8.86±0.73)％,(7.26±0.62)％ and (6.92±0.58)％,respectively,which decreased with the decreasing concentration of droperidol (F=50.01,P＜0.01).When the concentration of droperidol was 1.0× 10-4 mol/L,the uptake rate reached the lowest with inhibiting rate of 51.85％.(2) The autoradiography showed that the pancreas gray scale value of group A was 1.21×106 digital light units (DLU)/mm2.The pancreas gray scale value of groups B to F decreased with increasing concentration of inhibitor:0.93× 106,0.77× 106,0.59× 106,0.32× 106 and 0.25×106 DLU/mm2,respectively.Conclusions 18F-Fallypride may specifically and efficiently bind to dopamine receptors of islet cells.It may be a potential tracer for islet cells imaging.

Objective To investigate the CT imaging features of solid pseudopapillary tumor of the pancreas (SPTP) and to improve the preoperative diagnostic accuracy. Methods A retrospective analysis was performed on the CT manifestations of 21 cases of SPTP confirmed by pathology and surgery. Results In the 21 cases of SPTP, 19 were young and middle-aged female (range: 9～29 years old). The lesions were located in the pancreatic head and neck in 13 cases, and in the pancreatic body and tail in 4 cases each. The maximum diameter of tumor was 3 ～ 15 cm (mean 7.5cm). CT showed a single, round-like, cystic and solid mass in the pancreas. Eighteen cases had a complete capsule, and 3 cases had poorly defined margin with surrounding tissue. 5 cases of tumor were encapsulated or appeared scattered calcification in the center, only 1 case had pancreatic duct dilation (about 5mm in diameter), and no patient had bile duct changes. After enhanced scanning, the tumor capsule and the solid part were mildly to moderately enhanced during arterial phase, and they were significantly enhanced during portal venous phase and equilibrium phase. The cystic part was not enhanced, but the capsule was significantly enhanced. Conclusions CT manifestations of solid pseudopapillary tumor of the pancreas have certain characteristics, and when combined with clinical and imaging manifestations, accurate diagnosis generally can be made.

Objective To evaluate the diagnostic value of the metabolic parameters for differentiating focal autoimmune pancreatitis (F-AIP) and pancreatic cancer (PC) by dual time 18F-FDG PET/CT scan.Methods Ten F-AIP patients and 20 PC patients in Changhai Hospital from May 2011 to November 2014 were enrolled in this study.All the AIP patients were histological confirmed or diagnosed by clinical follow up.The PC patients were histological confirmed and gender-and age-matched with F-AIP patients.50％ SUVmax was set as the threshold to fine-tune the boundary of interest.The extracted parameters included SUV SUV metabolic tumor volume (MTV),total lesion glycolysis (TLG),target-to-background ratio (TBR) and the retention indexes(RI) of all the parameters above.The PET/CT imaging features were also observed.Results The high metabolic lesions were observed in both F-AIP patients and PC patients.There were 6 F-AIP patients whose lesion was located in pancreas head,4 F-AIP patients whose lesion was located in pancreas body and tail.There were 12 PC patients whose lesion was located in pancreas head,8 PC patients whose lesion was located in pancreas body and tail.In F-AIP patients,2 cases had dilated pancreatic duct,6 had dilated biliary duct,8 had increased metabolism in mediastinal lymph node and 2 had abdominal lymphadenopathy,which were 8,5,5 and 14 cases in PC patients.The positive rate of mdeiastinal lymphadenopathy in F-AIP patients was statistically higher than that in PC patients,while the positivity rate of abdominal lymphadenopathy in AIP patients was lower than that in PC patients.The difference was statistically significant (both P ＜ 0.05).There were no statistical differences on the positivity rate of the dilated pancreatic duct,intra-and extra-hepatic bile duct between two groups.SUVmax,SUVmean and MTV in F-AIP were 5.37 ± 0.88,3.48 ± 0.66,21.79 ±15.60 in early stage and 6.45 ±1.51,4.23 ± 1.10,19.36 ± 14.63 in delayed stage,and those in PC were 8.31 ±3.08,5.41±1.95,9.26±8.35 in early stage,and 9.75±3.86,6.36±2.56,9.09±10.71 in delayed stage.SUVmax and SUVmean in F-AIP were lower than those in PC,whereas MTV were larger in F-AIP than that in PC.ROC curves for SUVmax,SUVmean and MTV were made.The AUC of SUV was the highest at 0.85,the cut-off value was 4.45,the corresponding sensitivity was 65％ and the specificity was 90％.TLG,TBR and RI of all the parameters were not statistically different in F-AIP and PC.Conclusions The 18F-FDG PET/CT metabolic parameters,such as SUVmax,SUVmean,MTV,could be of special diagnostic significance in discriminating F-AIP from PC.

Objective To study diaphragmatic strength in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) during mechanical ventilation (MV), and to explore the predictive value of maximal transdiaphragm pressure (Pdi max) for successful extubation. Methods A prospective study was conducted. Twenty-one patients with AECOPD receiving MV admitted to intensive care unit (ICU) of Shanghai East Hospital of Tongji University of School Medicine from February 2015 to May 2017 were enrolled. Pdi max value was measured by using esophageal and gastric balloon catheters within 24 hours of intubation until the day the patient underwent extubation or died. In addition, the C-reactive protein (CRP), serum albumin (Alb) and prealbumin (PA) during MV were recorded. Pearson correlation was used to analyze the correlations between Pdi max and CRP, Alb and PA. The receiver operating characteristic curve (ROC) was used to cumulate Pdi max value of the successful weaning. Results Tracheotomy was done in 2 patients, and 2 patients quit the study. The remaining 17 patients were included in the investigative protocol. Six of the 17 patients died and 11 patients were successfully extubated. ① Mean Pdi max decreased progressively over time in 17 patients of AECOPD during MV. There were no significant changes in Pdi max at 1-2 days of MV. Mean Pdi max at 7 days was significantly lower than that at 3 days [cmH2O (1 cmH2O = 0.098 kPa): 20.2±4.2 vs. 28.1±4.4, P < 0.01]. By the end of the evaluation period at 11 days of MV, mean Pdi max decreased about 38.7% to the 1 day of MV (cmH2O: 19.8±4.7 vs. 32.3±3.9, P < 0.01). During MV, CRP, Alb and PA showed a downward trend. ② Mean Pdi max and the Pdi max before extubation in patients with difficulty extubation from MV was lower than that in successful weaning [Mean Pdi max (cmH2O): 25.2±5.4 vs. 28.9±5.8, Pdi max before extubation (cmH2O): 16.9±2.8 vs. 26.8±6.6, both P < 0.01]. ③ There was significantly negative correlation between Pdi max value and CRP (r = -0.799, P = 0.000). There was significantly positive correlation between Pdi max value and serum Alb (r = 0.613, P = 0.008) and PA (r = 0.661,P = 0.004). ④ ROC curve analysis showed that the area under the ROC curve (AUC) for predicting weaning success in the patients with AECOPD was 0.902. The sensitivity of the diagnosis was 81.8% and the specificity was 100% when cut-off value of Pdi max was 23.2 cmH2O. Conclusions MV induced the reduction of diaphragmatic contractility in a time-dependent manner. The Pdi max in patients with difficult extubation from MV was lower than that in successful weaning. The Pdi max could be a parameter to predict the successful extubation in patients with AECOPD during MV.

Objective:To explore the value of coronary artery plaque progression parameters based on coronary CT angiography (CCTA) in predicting the occurrence of major adverse cardiovascular events (MACE) in patients with non-obstructive coronary artery disease.Methods:The study included clinical, imaging, and prognosis (MACE) parameters of non-obstructive coronary artery disease patients who underwent CCTA at the First Affiliated Hospital of Nanjing Medical University from September 2010 to December 2022. Patients were grouped based on the occurrence of MACE, and differences in clinical data, plaque baseline, and progression parameters between the two groups were compared. Univariate and multivariate Cox regression analyses were employed to identify factors that could effectively predict the occurrence of MACE in patients. Models were constructed using plaque baseline parameters, plaque progression parameters, and a combination of both. The concordance index-time curve, net reclassification improvement and integrated discrimination improvement were used to evaluate the risk stratification ability of the models.Results:A total of 258 patients were included, of whom 62 cases experienced MACE during the follow-up period. In comparison to the MACE(-) group, patients in the MACE(+) group exhibited longer lesion length, greater degree of stenosis, larger plaque total volume, calcified plaque volume, non-calcified plaque volume, fibrous plaque volume, total plaque burden, lipid-rich plaque burden, higher peri-coronary adipose tissue attenuation index (FAI), and annual change of diameter stenosis(ΔDS/y). There were also more cases of coronary artery disease reporting and data system upgrades and non-obstructive progression to obstructive status ( P<0.05). Multivariate Cox analysis revealed that FAI, ΔDS/y, and non-obstructive progression to obstructive status were independent predictors of MACE occurrence. Concordance index-time curve results indicated that the combined model had a better predictive efficacy for MACE in patients with non-obstructive coronary artery disease compared to models based on plaque baseline parameters and plaque progression parameters. Conclusion:The plaque progression parameters and FAI based on CCTA have the potential to predict the high-risk population for MACE in patients with non-obstructive coronary artery disease, demonstrating good risk stratification value.