Gram-negative bacteria are the common pathogens causing nosocomial infections.The drug resistance of gram-negative bacteria has become increasingly serious in last two decades.Carbapenems were once considered as the last line of defense against serious infections of gram-negative pathogens.As carbapenemase-producing strains are spreading, the incidence of infections caused by carbapenem-resistant isolates is increasing worldwide.The pathogens are usually multiple drug resistant strains or extensively drug resistant strains, and effective treatment options are limited, even there are no more drugs in certain conditions.This article focuses on appropriate antibiotics and therapeutic strategies for effective control of infections with carbapenem-resistant gram-negative pathogens.

Objective To investigate the ultrasonograms of biliary sludge and its relationship with the prognosis of patients after liver transplantation.Methods Ultrasonograms of 36 patients with biliary sludge after liver transplantation were retrospectively analyzed.These patients were divided into two groups according to the different treatment outcomes:poor prognosis group and favorable prognosis group.The characteristics of initial ultrasonograms of biliary sludge when they were found at first time compared between two groups .Results Biliary sludge combined with ischemic-type biliary lesions accounted for 95% ( 19/20 ) in poor prognosis group while 13%(2/16)in favorable prognosis group.There was significant difference between two groups (P<0.05).In favorable prognosis group , biliary sludge was found locating in hepatic hilar region in all 16 cases (16/16) and the sludge had clear boundaries dissociated with bile duct walls were observed in 14 cases (14/16).There was no incrassation of bile duct walls in hepatic hilar region , nor dilation of intrahepatic bile ducts observed in 14 cases ( 14/16 ).In poor prognosis group , biliary sludge was observed widespread not only in hepatic hilar region but also in intrahepatic biliary ducts in 10 cases ( 10/20 ) , and the boundaries between sludge and bile duct walls were vague in 15 cases (15/20).Obvious incrassation of bile duct walls in hepatic hilar region was observed in 16 cases (16/20), and dilation of intrahepatic bile ducts was observed in 19 cases (19/20).There were significant differences in the above 4 ultrasound features between two groups (all in P<0.05).Conclusions There are differences in the ultrasonograms of biliary sludge between different prognosis groups.Biliary sludge combined with ischemic-type biliary lesions suggests a poor prognosis , which may need more active interventional treatments.

Objective To investigate a diabetic retinopathy ( DR ) detection algorithm based on transfer learning in small sample dataset. Methods Total of 4465 fundus color photographs taken by Gaoyao People ' s Hospital was used as the full dataset. The model training strategies using fixed pre-trained parameters and fine-tuning pre-trained parameters were used as the transfer learning group to compare with the non-transfer learning strategy that randomly initializes parameters. These three training strategies were applied to the training of three deep learning networks:ResNet50,Inception V3 and NASNet. In addition,a small dataset randomly extracted from the full dataset was used to study the impact of the reduction of training data on different strategies. The accuracy and training time of the diagnostic model were used to analyze the performance of different training strategies. Results The best results in different network architectures were chosen. The accuracy of the model obtained by fine-tuning pre-training parameters strategy was 90. 9％,which was higher than the strategy of fixed pre-training parameters (88. 1％) and the strategy of randomly initializing parameters ( 88. 4％) . The training time for fixed pre-training parameters was 10 minutes,less than the strategy of fine-tuning pre-training parameters ( 16 hours ) and the strategy of randomly initializing parameters (24 hours). After the training data was reduced,the accuracy of the model obtained by the strategy of randomly initializing parameters decreased by 8. 6％ on average,while the accuracy of the transfer learning group decreased by 2. 5％ on average. Conclusions The proposed automated and novel DR detection algorithm based on fine-tune and NASNet structure maintains high accuracy in small sample dataset,is found to be robust,and effective for the preliminary diagnosis of DR.

Objective To investigate the value of three-dimensional contrast-enhanced ultrasound (3D-CEUS) in diagnosing the hepatic artery complications after liver transplantation.Methods A total of 26 liver transplant donors or recipients suspected with hepatic artery complications were examined by color Doppler ultrasound, two-dimensional contrast-enhanced ultrasound ( 2D-CEUS ) and 3D-CEUS.The successful reconstruction rates of 3D-CEUS and the three-dimensional image quality of reconstructed hepatic arteries were evaluated.Results In the 26 patients, 21 hepatic arteries could be visualized with a successful reconstruction rate 81%.The three-dimensional images of hepatic arteries by 3D-CEUS were continuous.The coronal ( Z-axle) , fine or circuitous branches or tributaries could be visualized well.The segmental hepatic arteries origin could be determined and the spatial relationship of vessels could be visualized definitely.Conclusions The 3D-CEUS images are intuitive , three-dimensional and clear , and have clinical application value in diagnosing of hepatic artery complications after liver transplantation.

Objective:To analyze the clinical characteristics, therapeutic options and risk factors of mortality in patients with carbapenem-resistant Acinetobacter baumannii (CRAB) bloodstream infection, and to provide evidence for clinical treatment option and prognosis evaluation of CRAB bloodstream infections. Methods:A retrospective study was carried out in 224 patients with confirmed diagnosis of CRAB bloodstream infection during the period from January 2012 to December 2017 in West China Hospital, Sichuan University. The patients were divided into the death group and the survival group according to the survival status 28 days after collecting blood samples. The clinical features and therapeutic options of antibacterial drugs were reviewed. Student′s t test was used for analyzing normally distributed data and Mann-Whitney U test for non-normal data.Chi-square test was used for categorical variables. Univariate and multivariate logistic analysis were used to analyze the risk factors of mortality associated with CRAB bloodstream infection. Results:Among 224 cases of CRAB bloodstream infection, 121 cases died (54.02%). These patients were mainly in intensive care unit (ICU) and hematology department. The common underlying diseases were severe acute pancreatitis and severe cardiovascular events. The interleukin (IL)-6 level (median (interquartile range)) in the death group (480.40 ng/L (1 432.95 ng/L)) was higher than that of the survival group (107.05 ng/L (263.08 ng/L)), the difference was statistically significant ( Z=4.526, P<0.01). The procalcitionin (PCT) levels in the death group and the survival group were 3.81 μg/L (17.26 μg/L) and 2.12 μg/L (12.74 μg/L), respectively, with no difference between the two groups ( P>0.05). The death rate of empirical treatment with a single or more non-active antimicrobial agents was 57.14% (64/112), that of monotherapy with active agent was 45.68% (37/81), and that of combination therapy with at least one active drug was 64.52% (20/31). The differences had no statistical significance ( P=0.130). The logistic regression analysis showed that the risk factors of mortality associated with CRAB bloodstream infection were renal dysfunction (odds ratio ( OR)=2.181, P=0.024) and multiple organ dysfunction syndrome (MODS; OR=20.376, P<0.01). Conclusions:The fatality rate of patients with CRAB bloodstream infection is high. These patients with renal dysfunction or MODS have poor prognosis. In addition to early effective antibacterial therapy, individual comprehensive treatment should be implemented in order to improve the curative effect.