Objective To investigate the expression of sphingosine kinase 1(SphK1)and NF-κB in colon carcinoma tissues and their correlation with clinicopathologic features.Methods Sixty-six paraffinembedded colon carcinoma samples and 66 fresh colon carcinoma samples were tested using immunohistochemistry,RT-PCR and Western blot,respectively.Results In 66 fresh colon carcinoma samples,the positive rate of SphK1 and NF-κB mRNA expression were 84.85％(56/66)and 74.24％(49/66),while the positive rate of SphK1 and NF-κB protein detected by Western blot were 78.79％(52/66)and 69.70％(46/66).The positive rates were higher than those in the adjacent tissues[mRNA:63.64％(42/66),48.49％(32/66);protein:57.58％(38/66),45.45％(30/66)]and the normal mucosa [mRNA:42.42％(28/66),25.76％(17/66); protein:36.36％(24/66),24.24％(16/66)],with statistical significances(all P values ＜ 0.05).The mean expressive levels of SphK1 and NF-kB mRNA and protein in colon carcinoma were both significantly higher than those in the adjacent tissues and the normal mucosa(mRNA:0.55±0.06 vs0.35 ±0.05 vs0.25±0.05,0.75 ±0.06 vs0.43±0.05 vs0.30±0.04 ; protein:0.77 ± 0.05 vs 0.38 ± 0.06 vs 0.12 ± 0.03,0.45 ± 0.08 vs 0.23 ± 0.05 vs 0.13 ± 0.03 ;all P values ＜ 0.05).There was a close correlation between SphK1 and NF-kB expression levels (r =0.459,P =0.036).The results of immunohistochemistry were similar to those of RT-PCR and Western blot.Overexpression of SphK1 and NF-κB in colon carcinoma was related with depth of invasion,distant and lymph node metastasis and Dukes'stages(all P values ＜0.05).The expression of SphK1 was also related with differentiation(P ＜ 0.05).Conclusions Overexpression of SphK1 and NF-κB may be involved in the pathogenesis and progression of colon carcinoma.Moreover,SphK1 and NF-κB may be correlated with the invasion and metastasis of colon carcinoma.

Objective To investigate the distribution of common carbapenem resistance genes and virulence genes in and understand the molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae (CRKP) strains.Methods A total of 84 non-duplicate CRKP isolates were collected from Renji Hospital,Shanghai Jiao Tong University School of Medicine and Changzheng Hospital,the Second Military Medical University,in 2015.Kirby-Bauer disk diffusion method was used to test their susceptibility to 15 antimicrobial agents.The HM phenotype of K.pneumoniae was determined by string test.Carbapenem-resistant genes and virulence genes were detected by polymerase chain reaction (PCR).The molecular epidemiology of the 84 isolates were further analyzed by multi locus sequence typing (MLST).The population structure of CRKPs was evaluated by eBURST with the results of MLST.Results Antimicrobial susceptibility test showed that 84 isolates were highly resistant to most antimicrobial agents such as carbapenems,penicillins,cephalosporins and aztreonam.More than 90％ of the strains were resistant to most of the antibiotics tested except ciprofloxacin (77.4％,65/84) and amikacin (82.1％,69/84).Two strains showed HM phenotype.PCR results showed that 90.5％ (76/84) of the strains were positive for blaKPC-2,1.2％ (1/84) positive for blaNDM and blaIMP each,but either blaOXA or blaVIM was not identified.The overall prevalence of virulence genes was low except for mrkD (97.6％,82/84),ybtS (92.9％,78/84) and entB (100％,84/84).Eight sequence types (STs) were obtained.The dominant clone was ST11 (84.5％,71/84),and the two strains of HM phenotype were ST11.eBURST analysis identified 2 ST groups among the 84 CRKPs.Each ST group includes 2 ST types (ST11 and ST1869,ST15 and ST709),respectively.The other four ST types were single ST type.In this study,71 strains of ST11,4 ST15 and 4 ST323 belonged to CC258,CC15 and CC163 clones,respectively.Conclusions CRKP is highly resistant to the commonly used antibiotics.The multidrug resistance or pandrug-resistance of K.pneumoniae is mainly associated with the expression of blaKPC-2 gene.Three virulence genes mrkD,ybtS and entB are highly prevalent in the CRKP isolates.The dominant clone of KPC-producing K.pneumoniae is ST11 in both hospitals.

Objective The aim of this study was to evaluate the commercial SepsityperTM kit and serum separator tube coupled with matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry for direct identification of microorganisms in a blood culture system.Methods A total of 138 clinical blood samples from clinical laboratory in Renji hospital were tested with two methods respectively from April to June of 2016.Performance of the assays were compared against that of conventional bacterial culture as a reference.Results A total of 138 nonduplicate positive blood culture samples were collected,including 70 (53.03％) gram negative samples,57 (43.18％) gram positive samples,3 fungus samples,2 mixed samples,and 6 false positive samples which were excluded from further analysis.The accuracy rate of SepsityperTM kit and serum separator tube was 91.67％ and 84.09％ in rapid identification of pathogen from blood samples,83.33％ and 61.36％ in correct identification to species level.The accuracy rate of SepsityperTM kit and serum separator tube was 98.57％ and 95.71％ in identifying gram-negative bacteria,87.72％ and 78.59％ in identifying gram-positive bacteria,respectively.The turnaround time for identification of each sample was 40 min by the commercial SepsityperTM kit and 25 min by serum separator tube.Conclusions MALDI SepsityperTM kit has shown slightly higher accuracy rate in identification of pathogen from blood sample than serum separator tube,but the difference is not significant (91.67％ vs.84.09％,P＞0.05).Compared with MALDI SepsityperTM kit,serum separator tube is a rapid,easy,and cost-effective pretreatment method for direct identification of microorganisms from blood cultures using MALDI-TOF mass spectrometry.

ObjectiveTo investigate a suspected outbreak of carbapenem-resistant Acinetobacter baumannii （CRAB） nosocomial infection in an intensive care unit （ICU） and provide scientific evidence for prevention and control of multi-drug resistant nosocomial infection. MethodsClinical and epidemiological data of 4 patients with CRAB infection were retrospectively investigated in the ICU of Renji Hospital in November 2021. Environmental hygiene monitoring and multilocus sequence typing （MLST） were conducted and intervention measures were taken. ResultsA total of 4 cases with CRAB infection were identified， among which 1 case was determined to be community-acquired and3 cases were hospital-acquired. The isolated strains shared the same drug resistance， and were all classified into ST368 type. In the surface and hand samples （n=40）， 2 CRAB strains were detected in the air filter beside the bed of the first case， with a detection rate of 5%. After adopting comprehensive prevention and control strategies， including environmental cleaning and disinfection， hand hygiene， staff management and training， and supervision， no similar case with CRAB infection was found. ConclusionThis suspected outbreak of CRAB nosocomial infection may be induced by inadequate environmental cleaning and disinfection， and inadequate implementation of hand hygiene. Timely identification， investigation， and targeted measures remain crucial to effective control of possible nosocomial infection.