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author:("Liu, changing")
1.  Hospital Acquired Pneumonia Due to Achromobacter spp. in a Geriatric Ward in China: Clinical Characteristic, Genome Variability, Biofilm Production, Antibiotic Resistance and Integron in Isolated Strains 
Background: Hospital-acquired pneumonia (HAP) due to Achromobacter has become a substantial concern in recent years. However, HAP due to Achromobacter in the elderly is rare.
Methods: A retrospective analysis was performed on 15 elderly patients with HAP due to Achromobacter spp., in which the sequence types (STs), integrons, biofilm production and antibiotic resistance of the Achromobacter spp. were examined.
Results: The mean age of the 15 elderly patients was 88.8 ± 5.4 years. All patients had at least three underlying diseases and catheters. Clinical outcomes improved in 10 of the 15 patients after antibiotic and/or mechanical ventilation treatment, but three patients had chronic infections lasting more than 1 year. The mortality rate was 33.3% (5/15). All strains were resistant to aminoglycosides, aztreonam, nitrofurantoin, and third- and fourth-generation cephalosporins (except ceftazidime and cefoperazone). Six new STs were detected. The most frequent ST was ST306. ST5 was identified in two separate buildings of the hospital. ST313 showed higher MIC in cephalosporins, quinolones and carbapenems, which should be more closely considered in clinical practice. All strains produced biofilm and had integron I and blaOXA-114-like. The main type was blaOXA-114q. The variable region of integron I was different among strains, and the resistance gene of the aminoglycosides was most commonly inserted in integron I. Additionally, blaPSE-1 was first reported in this isolate.
Conclusion: Achromobacter spp. infection often occurs in severely ill elders with underlying diseases. The variable region of integrons differs, suggesting that Achromobacter spp. is a reservoir of various resistance genes.
PMCID: PMC4860489  PMID: 27242678
hospital-acquired pneumonia; Achromobacter; biofilm; elderly; integron
2.  NDM-1 encoded by a pNDM-BJ01-like plasmid p3SP-NDM in clinical Enterobacter aerogenes 
A carbapenem-nonsusceptible Enterobacter aerogenes strain named 3-SP was isolated from a human case of pneumonia in a Chinese teaching hospital. NDM-1 carbapenemase is produced by a pNDM-BJ01-like conjugative plasmid designated p3SP-NDM to account for carbapenem resistance of 3-SP. p3SP-NDM was fully sequenced and compared with all publically available pNDM-BJ01-like plasmids. The genetic differences between p3SP-NDM and pNDM-BJ01 include only 18 single nucleotide polymorphisms, a 1 bp deletion and a 706 bp deletion. p3SP-NDM and pNDM-BJ01 harbor an identical Tn125 element organized as ISAba125, blaNDM−1, bleMBL, ΔtrpF, dsbC, cutA, ΔgroES, groEL, ISCR27, and ISAba125. The blaNDM−1 surrounding regions in these pNDM-BJ01-like plasmids have a conserved linear organization ISAba14-aphA6-Tn125-unknown IS, with considerable genetic differences identified within or immediately downstream of Tn125. All reported pNDM-BJ01-like plasmids are exclusively found in Acinetobacter, whereas this is the first report of identification of a pNDM-BJ01-like plasmid in Enterobacteriaceae.
PMCID: PMC4396501  PMID: 25926823
Enterobacter aerogenes; NDM-1; Plasmid; p3SP-NDM
3.  Comparison of Different Drug Susceptibility Test Methods To Detect Rifampin Heteroresistance in Mycobacterium tuberculosis 
We compared the efficiencies of different drug susceptibility testing methods in detecting rifampin (RIF) heteroresistance in Mycobacterium tuberculosis. Our data revealed that the broth dilution method found more resistance than MGIT did (P = 0.046) for the low-resistance group. Similarly, the broth dilution method was more sensitive in detecting RIF heteroresistance in subpopulations with low growth rates than was MGIT (P = 0.033). In conclusion, our data demonstrated that the broth dilution method was more sensitive than MGIT in detecting RIF heteroresistance.
PMCID: PMC4135805  PMID: 25022589
4.  Time course changes of oxidative stress and inflammation in hyperoxia-induced acute lung injury in rats 
Therapies with high levels of oxygen are commonly used in the management of critical care. However, prolonged exposure to hyperoxia can cause acute lung injury. Although oxidative stress and inflammation are purported to play an important role in the pathogenesis of acute lung injury, the exact mechanisms are still less known in the hyperoxic acute lung injury (HALI).
Materials and Methods:
In this study, we investigated the time course changes of oxidative stress and inflammation in lung tissues of rats exposed to >95% oxygen for 12-60 hr.
We found that at 12 hr after hyperoxia challenge, the activities of superoxide dismutase and glutathione peroxidase were significantly reduced with remarkably increased lipid peroxidation. At 12 hr, NF-κB p65 expression was also upregulated, but Iκ-Bα expression showed a remarkable decline. Significant production of inflammatory mediators, e.g, interleukin-1β, occurred 24 hr after hyperoxia exposure. In addition, the expression of intracellular adhesion molecule 1 expression and the activity of myeloperoxidase were significantly increased at 24 hr with a peak at 48 hr.
Our data support that hyperoxia-induced oxidative damage and NF-κB pathway activation implicate in the early phase of HALI pathogenesis.
PMCID: PMC4366750  PMID: 25810882
Acute lung injury; Hyperoxia; Inflammation; Oxidative stress
5.  Discrimination of sepsis stage metabolic profiles with an LC/MS-MS-based metabolomics approach 
BMJ Open Respiratory Research  2014;1(1):e000056.
To identify metabolic biomarkers that can be used to differentiate sepsis from systemic inflammatory response syndrome (SIRS), assess severity and predict outcomes.
65 patients were involved in this study, including 35 patients with sepsis, 15 patients with SIRS and 15 normal patients. Small metabolites that were present in patient serum samples were measured by liquid chromatography mass spectrometry techniques and analysed using multivariate statistical methods.
The metabolic profiling of normal patients and patients with SIRS or sepsis was markedly different. A significant decrease in the levels of lactitol dehydrate and S-phenyl-d-cysteine and an increase in the levels of S-(3-methylbutanoyl)-dihydrolipoamide-E and N-nonanoyl glycine were observed in patients with sepsis in comparison to patients with SIRS (p<0.05). Patients with severe sepsis and septic shock displayed lower levels of glyceryl-phosphoryl-ethanolamine, Ne, Ne dimethyllysine, phenylacetamide and d-cysteine (p<0.05) in their sera. The profiles of patients with sepsis 48 h before death illustrated an obvious state of metabolic disorder, such that S-(3-methylbutanoyl)-dihydrolipoamide-E, phosphatidylglycerol (22:2 (13Z, 16Z)/0:0), glycerophosphocholine and S-succinyl glutathione were significantly decreased (p<0.05). The receiver operating characteristic curve of the differential expression of these metabolites was also performed.
The body produces significant evidence of metabolic disorder during SIRS or sepsis. Seven metabolites may potentially be used to diagnose sepsis.
Trial registration number identifier NCT01649440.
PMCID: PMC4265126  PMID: 25553245
Respiratory Infection
6.  IMP-1 encoded by a novel Tn402-like class 1 integron in clinical Achromobacter xylosoxidans, China 
Scientific Reports  2014;4:7212.
Achromobacter xylosoxidans strain A22732 is isolated from a pneumonia patient in China and produces carbapenemases OXA-114e and IMP-1, which are encoded by chromosome and plasmid, respectively, and confer resistance to multiple ß-lactam antibiotics including carbapenems. The blaIMP-1 gene together with aacA7 and orfE is captured by a novel Tn402-like class 1 integron in a conjugative IncP-1ß plasmid. In addition to the intrinsic integron promoter PcW, there is still a blaIMP-1 gene cassette-specific promoter. This is the first report of carbapenemase-encoding IncP-1ß plasmid in clinical bacterial isolate.
PMCID: PMC4245530  PMID: 25428613
7.  Genomic and transcriptomic analysis of NDM-1 Klebsiella pneumoniae in spaceflight reveal mechanisms underlying environmental adaptability 
Scientific Reports  2014;4:6216.
The emergence and rapid spread of New Delhi Metallo-beta-lactamase-1 (NDM-1)-producing Klebsiella pneumoniae strains has caused a great concern worldwide. To better understand the mechanisms underlying environmental adaptation of those highly drug-resistant K. pneumoniae strains, we took advantage of the China's Shenzhou 10 spacecraft mission to conduct comparative genomic and transcriptomic analysis of a NDM-1 K. pneumoniae strain (ATCC BAA-2146) being cultivated under different conditions. The samples were recovered from semisolid medium placed on the ground (D strain), in simulated space condition (M strain), or in Shenzhou 10 spacecraft (T strain) for analysis. Our data revealed multiple variations underlying pathogen adaptation into different environments in terms of changes in morphology, H2O2 tolerance and biofilm formation ability, genomic stability and regulation of metabolic pathways. Additionally, we found a few non-coding RNAs to be differentially regulated. The results are helpful for better understanding the adaptive mechanisms of drug-resistant bacterial pathogens.
PMCID: PMC4147364  PMID: 25163721
8.  Comparative genomic analysis of Klebsiella pneumonia (LCT-KP214) and a mutant strain (LCT-KP289) obtained after spaceflight 
BMC Genomics  2014;15:589.
With the development of space science, it is important to analyze the relationship between the space environment and genome variations that might cause phenotypic changes in microbes. Klebsiella pneumoniae is commonly found on the human body and is resistant to multiple drugs. To study space-environment-induced genome variations and drug resistance changes, K. pneumoniae was carried into outer space by the Shenzhou VIII spacecraft.
The K. pneumoniae strain LCT-KP289 was selected after spaceflight based on its phenotypic differences compared to the ground-control strain. Analysis of genomic structural variations revealed one inversion, 25 deletions, fifty-nine insertions, two translocations and six translocations with inversions. In addition, 155 and 400 unique genes were observed in LCT-KP214 and LCT-KP289, respectively, including the gene encoding dihydroxyacetone kinase, which generates the ATP and NADH required for microbial growth. Furthermore, a large number of mutant genes were related to transport and metabolism. Phylogenetic analysis revealed that most genes in these two strains had a dN/dS value greater than 1, indicating that the strain diversity increased after spaceflight. Analysis of drug-resistance phenotypes revealed that the K. pneumoniae strain LCT-KP289 was resistant to sulfamethoxazole, whereas the control strain, LCT-KP214, was not; both strains were resistant to benzylpenicillin, ampicillin, lincomycin, vancomycin, chloramphenicol and streptomycin. The sulfamethoxazole resistance may be associated with sequences in Scaffold7 in LCT-KP289, which were not observed in LCT-K214; this scaffold contained the gene sul1. In the strain LCT-KP289, we also observed a drug-resistance integron containing emrE (confers multidrug resistance) and ant (confers resistance to spectinomycin, streptomycin, tobramycin, kanamycin, sisomicin, dibekacin, and gentamicin). The gene ampC (confers resistance to penicillin, cephalosporin-ii and cephalosporin-i) was present near the integron. In addition, 30 and 26 drug-resistance genes were observed in LCT-KP289 and LCT-KP214, respectively.
Comparison of a K. pneumoniae strain obtained after spaceflight with the ground-control strain revealed genome variations and phenotypic changes and elucidated the genomic basis of the acquired drug resistance. These data pave the way for future studies on the effects of spaceflight.
PMCID: PMC4226956  PMID: 25015528
Klebsiella pneumoniae; Comparative genomic analysis; Virulence gene; Resistance gene
9.  Genome Sequence of Pseudomonas aeruginosa Strain LCT-PA220, Which Was Selected after Space Flight by Using Biolog’s Powerful Carbon Source Utilization Technology 
Genome Announcements  2014;2(2):e00169-14.
To explore the changes of Pseudomonas aeruginosa in space flight, we present the draft genome sequence of P. aeruginosa strain LCT-PA220, which originated from a P. aeruginosa strain, ATCC 27853, that traveled on the Shenzhou-VIII spacecraft.
PMCID: PMC3953191  PMID: 24625870
10.  Genome Sequence of Escherichia coli Strain LCT-EC52, Which Acquired Changes in Antibiotic Resistance Properties after the Shenzhou-VIII Mission 
Genome Announcements  2014;2(2):e00081-14.
Escherichia coli is a ubiquitous opportunistic pathogen that colonizes the lower intestines of humans and causes several diseases, such as septicemia, pneumonia, and urinary tract infections. Here, we present the draft genome sequence of E. coli strain LCT-EC52, which originated from E. coli strain CGMCC 1.2385 and acquired changes in antibiotic resistance following travel on the Shenzhou-VIII spacecraft.
PMCID: PMC3945497  PMID: 24604641
11.  Draft Genome Sequence of Enterococcus faecium Strain LCT-EF301, Which Shows Changes in Biochemical Metabolism following Space Flight 
Genome Announcements  2014;2(2):e00103-14.
An Enterococcus faecium strain was sent into space on the Shenzhou-VIII mission. After the space flight, the strain E. faecium LCT-EF301 was isolated and sequenced based on the changes to its metabolic properties.
PMCID: PMC3945498  PMID: 24604642
12.  Genome Sequence of Staphylococcus aureus Strain LCT-SA67, a Space Flight Strain with Altered Carbon Source Utilization Properties 
Genome Announcements  2014;2(1):e00095-14.
An increasing number of studies have confirmed that space flight environments can have a significant effect on a variety of microbial properties. To explore the effect of these environments on Staphylococcus aureus, we present the draft genome sequence of an S. aureus strain, named LCT-SA67, which was isolated after space flight.
PMCID: PMC3931362  PMID: 24558241
13.  Genome Sequence of Enterococcus faecium Strain LCT-EF297, Which Has Specific Biochemical Features 
Genome Announcements  2014;2(1):e00102-14.
An Enterococcus faecium strain was sent into space on the Shenzhou-VIII craft. After space flight, the strain E. faecium LCT-EF297 was selected based on its metabolic properties.
PMCID: PMC3931365  PMID: 24558244
14.  Draft Genome Sequence of Serratia marcescens Strain LCT-SM166, a Space Flight Strain with a Specific Carbon Source Utilization Pattern 
Genome Announcements  2014;2(1):e00069-14.
Serratia marcescens has been detected in space habitats. To explore the influence of the space flight environment on this bacterium, we investigated the genome sequence of LCT-SM166, which was isolated after space flight and has a specific carbon source utilization pattern.
PMCID: PMC3924376  PMID: 24526644
15.  Genome Sequence of Bacillus cereus Strain LCT-BC235, Carried by the Shenzhou VIII Spacecraft 
Genome Announcements  2014;2(1):e00665-13.
In order to explore the effect of space environments on Bacillus cereus, we determined the draft genome sequence of a B. cereus strain, LCT-BC235, which was isolated after space flight.
PMCID: PMC3886938  PMID: 24407625
16.  Genome Sequence of Klebsiella pneumoniae Strain LCT-KP182, Which Acquired Hemolytic Properties after Space Flight 
Genome Announcements  2014;2(1):e01088-13.
The Klebsiella pneumoniae strain LCT-KP182 acquired hemolytic properties after space flight. Here, we present the draft genome sequence of this strain.
PMCID: PMC3886944  PMID: 24407631
17.  Genome Sequence of Pseudomonas aeruginosa Strain LCT-PA41, with Changed Metabolism after Space Flight 
Genome Announcements  2014;2(1):e01124-13.
To explore the effects of space flight on microorganisms, Pseudomonas aeruginosa ATCC 27853 was sent into orbit for 398 h on the spacecraft ShenZhou VIII. Here, we present the draft genome sequence of the P. aeruginosa strain LCT-PA41, determined after space flight.
PMCID: PMC3886951  PMID: 24407638
18.  Draft Genome Sequence of Bacillus cereus LCT-BC25, Isolated from Space Flight 
Genome Announcements  2014;2(1):e00667-13.
Bacillus cereus strain LCT-BC25, which was carried by the Shenzhou VIII spacecraft, traveled in space for about 398 h. To investigate the response of B. cereus to space environments, we determined the genome sequence of B. cereus strain LCT-BC25, which was isolated after space flight.
PMCID: PMC3879601  PMID: 24385570
19.  A multi-omic analysis of an Enterococcus faecium mutant reveals specific genetic mutations and dramatic changes in mRNA and protein expression 
BMC Microbiology  2013;13:304.
For a long time, Enterococcus faecium was considered a harmless commensal of the mammalian gastrointestinal (GI) tract and was used as a probiotic in fermented foods. In recent decades, E. faecium has been recognised as an opportunistic pathogen that causes diseases such as neonatal meningitis, urinary tract infections, bacteremia, bacterial endocarditis and diverticulitis. E. faecium could be taken into space with astronauts and exposed to the space environment. Thus, it is necessary to observe the phenotypic and molecular changes of E. faecium after spaceflight.
An E. faecium mutant with biochemical features that are different from those of the wild-type strain was obtained from subculture after flight on the SHENZHOU-8 spacecraft. To understand the underlying mechanism causing these changes, the whole genomes of both the mutant and the WT strains were sequenced using Illumina technology. The genomic comparison revealed that dprA, a recombination-mediator gene, and arpU, a gene associated with cell wall growth, were mutated. Comparative transcriptomic and proteomic analyses showed that differentially expressed genes or proteins were involved with replication, recombination, repair, cell wall biogenesis, glycometabolism, lipid metabolism, amino acid metabolism, predicted general function and energy production/conversion.
This study analysed the comprehensive genomic, transcriptomic and proteomic changes of an E. faecium mutant from subcultures that were loaded on the SHENZHOU-8 spacecraft. The implications of these gene mutations and expression changes and their underlying mechanisms should be investigated in the future. We hope that the current exploration of multiple “-omics” analyses of this E. faecium mutant will provide clues for future studies on this opportunistic pathogen.
PMCID: PMC3879163  PMID: 24373636
E. faecium; Genome; Transcriptome; Proteome; Multi-omics
20.  Assessment of the green florescence protein labeling method for tracking implanted mesenchymal stem cells 
Cytotechnology  2012;64(4):391-401.
Although green fluorescent protein (GFP) labeling is widely accepted as a tracking method, much remains uncertain regarding the retention of injected GFP-labeled cells implanted in ischemic organs. In this study, we evaluate the effectiveness of GFP for identifying and tracking implanted bone marrow- mesenchymal stem cells (BM-MSCs) and the effect of GFP on the paracrine actions of these cells. MSCs isolated from rat femur marrow were transduced with a recombinant adenovirus carrying GFP. After transplantation of the GFP-labeled BM-MSCs into the infarct zone of rat hearts, the survival, distribution, and migration of the labeled cells were analyzed at 3, 7, 14, and 28 days. To evaluate the effect of GFP on the paracrine actions of BM-MSCs, Western blot analysis was performed to detect the expression of vascular endothelial growth factor (VEGF), b fibroblast growth factor (b FGF), tissue inhibitor of metalloproteinase-1 (TIMP-1) and matrix metalloproteinases-2 (MMP-2). GFP was successfully expressed by BM-MSCs in vitro. At 14 days after cell transplantation the GFP-positive cells could not be detected via confocal microscopy. By using a GFP antibody, distinct GFP-positive cells could be seen and quantitative analysis showed that the expression volume of GFP was 6.42 ± 0.92 mm3 after 3 days, 1.24 ± 0.76 mm3 after 7 days, 0.33 ± 0.03 mm3 after 14 days, and 0.09 ± 0.05 mm3 after 28 days. GFP labeling did not adversely affect the paracrine actions of BM-MSCs. GFP labeling could be used to track MSC distribution and their fate for at least 28 days after delivery to rat hearts with myocardial infarction, and this stem cell tracking strategy did not adversely affect the paracrine actions of BM-MSCs.
PMCID: PMC3397108  PMID: 22373822
Cell tracking; Green fluorescent protein; Mesenchymal stem cells; paracrine; Myocardial infarction
21.  Diagnostic Value of Dynamics Serum sCD163, sTREM-1, PCT, and CRP in Differentiating Sepsis, Severity Assessment, and Prognostic Prediction 
Mediators of Inflammation  2013;2013:969875.
Objective. To describe the dynamics changes of sCD163, soluble serum triggering receptor expressed on myeloid cells-1 (sTREM-1), procalcitonin (PCT), and C-reactive protein (CRP) during the course of sepsis, as well as their outcome prediction. Patients and Methods. An SIRS group (30 cases) and a sepsis group (100 cases) were involved in this study. Based on a 28-day survival, the sepsis was further divided into the survivors' and nonsurvivors' groups. Serum sTREM-1, sCD163, PCT, CRP, and WBC counts were tested on days 1, 3, 5, 7, 10, and 14. Results. On the ICU admission, the sepsis group displayed higher levels of sTREM-1, sCD163, PCT, and CRP than the SIRS group (P < 0.05). Although PCT and sTREM-1 are good markers to identify severity, sTREM-1 is more reliable, which proved to be a risk factor related to sepsis. During a 14-day observation, sCD163, sTREM-1, PCT, and SOFA scores continued to climb among nonsurvivors, while their WBC and CRP went down. Both sCD163 and SOFA scores are risk factors impacting the survival time. Conclusion. With regard to sepsis diagnosis and severity, sTREM-1 is more ideal and constitutes a risk factor. sCD163 is of a positive value in dynamic prognostic assessment and may be taken as a survival-impacting risk factor.
PMCID: PMC3713373  PMID: 23935252
22.  Genome Sequence of Enterococcus faecium Clinical Isolate LCT-EF128 
Journal of Bacteriology  2012;194(17):4765.
Enterococcus faecium, an opportunistic human pathogen that inhabits the gastrointestinal tracts of most mammals, has emerged as an important opportunistic nosocomial pathogen and is a prominent cause of multiresistant nosocomial infections. Here, we report the draft genome sequence of strain LCT-EF128, isolated from clinical specimens.
PMCID: PMC3415489  PMID: 22887667
23.  Draft Genome Sequence of Escherichia coli Strain LCT-EC59 
Genome Announcements  2013;1(1):e00242-12.
The space environment is a very special condition under which many organisms change many features. Escherichia coli is employed widely as a prokaryotic model organism in the fields of biotechnology and microbiology. Here, we present the draft genome sequence of E. coli strain LCT-EC59 exposed to space conditions.
PMCID: PMC3587949  PMID: 23469355
24.  Draft Genome Sequences of the Enterococcus faecium Strain LCT-EF258 
Genome Announcements  2013;1(1):e00147-12.
The space environment has been shown to affect microbes by altering various features, including morphology, growth rate, metabolism, virulence, drug resistance, and gene expression and mutation. Here we present the draft genome sequence of the Enterococcus faecium strain LCT-EF258, derived from the E. faecium strain CGMCC 1.1736, which was exposed to 17-day space flight.
PMCID: PMC3569272  PMID: 23409254
25.  Draft Genome Sequence of Serratia marcescens Strain LCT-SM213 
Journal of Bacteriology  2012;194(16):4477-4478.
Serratia marcescens is a species of Gram-negative, rod-shaped bacterium of the family Enterobacteriaceae. S. marcescens can cause nosocomial infections, particularly catheter-associated bacteremia, urinary tract infections, and wound infections. Here, we present the draft genome sequence of Serratia marcescens strain LCT-SM213, which was isolated from CGMCC 1.1857.
PMCID: PMC3416218  PMID: 22843602

Résultats 1-25 (34)