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Objective To investigate the distribution and drug resistance of pathogens isolated from blood culture samples from January 2012 to October 2013 to provide the basis for clinical lection of antibacterial drugs.Methods The blood samples were col-lected from the patients with suspected blood infection and cultured by the BD BACTEC 9120 automatic blood culture instrument. The samples with positive results were performed the bacterial identification and the drug sensitivity test by using the VITEK-2 COMPACT automatic bacterial identification instrument.Results A total of 969 strains of pathogens were isolated from blood cul-ture samples,including 540 strains(55.7%)of Gram-positive bacteria,413 strains(42.6%)of Gram-negative bacteria and 16 strains (1.7%)of fungi.The top 3 isolated pathogenic bacteria were Staphylococcus epidermidis,Escherichia coli and Staphylococcus au-reus.Staphylococcus epidermidis and Staphylococcus aureus were highly resistant to penicillin,sensitive to vancomycin and linezol-id;Escherichia coli and Klebsiella pneumoniae were highly sensitive to imipenem and Piperacillin/tazobactam.Conclusion It is nec-essary to understand the blood culture results timely so as to provide the basis for clinical antibacterial therapy and the improvement of the cure rate.
ABSTRACT
Objective To develop a time saving and sensitive cell culture system based on hepatitis C virus chimera expressing enhanced green fluorescent protein(EGFP) and to facilitate the study on HCV pathogenesis and screening of anti-HCV drugs.Methods Enhanced green fluorescent protein reporter gene and a mutation V2440L that can yield higher virus titers were introduced into the C-terminus of non-structural protein 5A (NS5A) of the JFH1 viral genome by using recombinant PCR.The viral RNA was transfected into Huh7.5 cells.Viral RNA in supernatant of HCV RNA-transfected cells was determined after transfection by RT-PCR.HCV replication and infection were determined by immunofluorescence assay.IFN-α was used to evaluate the feasibility of this system for anti-HCV drugs screening.Results The viral RNA replicated efficiently in transfected cells.These cells can produce HCV-EGFP reporter virus.Viral RNA levels in supernatant were 3.06× 105 copies/ml and 7.96×106 copies/ml at 72 h and 9 d after transfection,respectively.The virus titer reached to 104 FFU/ml 9 d after transfection.The expression of EGFP was inhibited by IFN-α in a dose dependent manner in Huh7.5 cells infected by HCV-EGFP reporter virus.Conclusion The recombinant HCV JFH1-EGFP reporter gene system is a time saving,cost effective and sensitive method for studying viral replication cycles and screening of anti-HCV drugs.
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ObjectiveTo develop a cell culture system with consistent expression of whole hepatitis C virus (HCV) gene and Renilla luciferase gene and to facilitate the study on HCV pathogenesis and the screening of new antiviral drugs.MethodsRenilla luciferase (RLuc) reporter gene and a mutation that could yield higher virus gene expression were introduced into the C-terminus of non-structural protein 5A (NS5A) of the JFH1 viral genome by using recombinant PCR.The viral RNA was transfected into Huh7.5 cells.Naǐve Huh7.5 cells were infected by the supernatant from the viral RNA transfected cells.HCV replication and infection were determined by virus titration,Renilla luciferase assay,immunofluorescence assay and western blotting.IFN-α was used to evaluate the feasibility of this system for anti-HCV new drug screening.ResultsThe viral RNA replicated efficiently in transfected cells.These cells could produce high titer of HCV-Rluc reporter virus and the virus titer reached to 1.5 × 104 FFU/ml at day 15 of posttransfection.The activity of Renilla luciferase was inhibited by IFN-α in a dose dependent manner in Huh7.5 cells infected by HCV-Rluc reporter virus.ConclusionThe recombinant HCV-JFH1-Rluc reporter gene system is sensitive and efficient.It can be a useful tool for high throughput screening of anti-HCV drugs.
ABSTRACT
Objective To analyze a population of cells on the right lower lateral of monocyte population in forward scatter/side scatter(FSC/SSC)(X-axis/Y-axis)scatterplot of peripheral blood leucocyte by flow cytometry(FCM)and its influencing factors.Methods The type of cells were identified based on cluster of differentiation antigen(CD)by FCM.The impact of temperature,hemolysin concentration,and incubation time was evaluated.Blood lipid tests were performed to observe the relation between them by statistical methods.Results (1) Phenotypo of this population of cells on the right lower lateral of monocytes in FSc/SSC scatterplot is CD+45 CD+13 CD+14 CD3- CD-19 ,which was the same as monocyte cells:(2)The monocytes in FSC/SSC scatterplot shifted to left side after using haemolysin;(3)The monocytes showed less resistance to antihemolysin in 37℃ than that in 220C:There were more monocytes shifting to left side with the increase of haemolysis time:(4)The swarming ratio of monocytes in patients (31.5%,40/126) Was higher than it in normal controls (5.1%,5/98)(x2=22.74,P<0.01);(5)The levels of total serum cholesterol(TC),triglyeride(TG),low density lipoprotein cholesterol(LDL-C), apoprotein B100(Apo B100) in patients with swarming monocytes were lower than that in the patients without swarming monocytes,(P<0.05).There was no statistical significance between the two groups with respect to levels of total bilirubin(TBIL),albumin(Alb),hish density lipoprotein cholesterol(HDL-C),apoprotein A I(Apo A I),lipoprotein(Lpa).Conclusions Peripheral blood monocytes can be divided in two groups in FSC/SSC scatterplot when analyzed with FCM.The presence of this population of cell Was related to resistance to hemolysin.It can be influenced by haemolysis time and incubation temperature.Therefore,the effect of swarming monocytes and abnormal cell membrane should be taken into consideration when the markers and function of monocytes are detected by FCM.