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author:("Liu, changing")
1.  Discrimination of sepsis stage metabolic profiles with an LC/MS-MS-based metabolomics approach 
BMJ Open Respiratory Research  2014;1(1):e000056.
Background
To identify metabolic biomarkers that can be used to differentiate sepsis from systemic inflammatory response syndrome (SIRS), assess severity and predict outcomes.
Methods
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.
Results
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.
Conclusions
The body produces significant evidence of metabolic disorder during SIRS or sepsis. Seven metabolites may potentially be used to diagnose sepsis.
Trial registration number
ClinicalTrial.gov identifier NCT01649440.
doi:10.1136/bmjresp-2014-000056
PMCID: PMC4265126  PMID: 25553245
Respiratory Infection
2.  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.
doi:10.1038/srep07212
PMCID: PMC4245530  PMID: 25428613
3.  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.
doi:10.1038/srep06216
PMCID: PMC4147364  PMID: 25163721
4.  Comparative genomic analysis of Klebsiella pneumonia (LCT-KP214) and a mutant strain (LCT-KP289) obtained after spaceflight 
BMC Genomics  2014;15:589.
Background
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.
Results
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.
Conclusions
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.
doi:10.1186/1471-2164-15-589
PMCID: PMC4226956  PMID: 25015528
Klebsiella pneumoniae; Comparative genomic analysis; Virulence gene; Resistance gene
5.  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.
Background
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.
Results
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.
Conclusion
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.
doi:10.1186/1471-2180-13-304
PMCID: PMC3879163  PMID: 24373636
E. faecium; Genome; Transcriptome; Proteome; Multi-omics
6.  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.
doi:10.1007/s10616-011-9417-y
PMCID: PMC3397108  PMID: 22373822
Cell tracking; Green fluorescent protein; Mesenchymal stem cells; paracrine; Myocardial infarction
7.  Diagnostic value of urine sCD163 levels for sepsis and relevant acute kidney injury: a prospective study 
BMC Nephrology  2012;13:123.
Background
Sepsis is a common syndrome in critically ill patients and easily leads to the occurrence of acute kidney injury (AKI), with high mortality rates. This study aimed to investigate the diagnostic value of urine soluble CD163 (sCD163) for identification of sepsis, severity of sepsis, and for secondary AKI, and to assess the patients’ prognosis.
Methods
We enrolled 20 cases with systemic inflammatory response syndrome (SIRS), 40 cases with sepsis (further divided into 17 sepsis cases and 23 severe sepsis cases) admitted to the intensive care unit (ICU), and 20 control cases. Results for urine sCD163 were recorded on the day of admission to the ICU, and AKI occurrence was noted.
Results
On the day of ICU admission, the sepsis group exhibited higher levels of urine sCD163 (74.8 ng/ml; range: 47.9-148.3 ng/ml) compared with those in the SIRS group (31.9 ng/ml; 16.8-48.0, P < 0.001). The area under the curve (AUC) was 0.83 (95% confidence interval [CI]: 0.72-0.94, P < 0.001) the sensitivity was 0.83, and the specificity was 0.75 (based on a cut-off point of 43.0 ng/ml). Moreover, the severe sepsis group appeared to have a higher level of sCD163 compared with that in the sepsis group (76.2; 47.2-167.5 ng/ml vs. 74.2; 46.2-131.6 ng/ml), but this was not significant. For 15 patients with AKI, urine sCD163 levels at AKI diagnosis were significantly higher than those of the remaining 35 sepsis patients upon ICU admission (121.0; 74.6-299.1 ng/ml vs. 61.8; 42.8-128.3 ng/ml, P = 0.049). The AUC for urine sCD163 was 0.688 (95% CI: 0.51-0.87, P = 0.049). Sepsis patients with a poor prognosis showed a higher urine sCD163 level at ICU admission (98.6; 50.3-275.6 ng/ml vs. 68.0; 44.8-114.5 ng/ml), but this was not significant. Patients with AKI with a poor prognosis had higher sCD163 levels than those in patients with a better prognosis (205.9; 38.6-766.0 ng/ml vs. 80.9; 74.9-141.0 ng/ml), but this was not significant.
Conclusions
This study shows, for the first time, the potential value of urine sCD163 levels for identifying sepsis and diagnosing AKI, as well as for assessment of patients’ prognosis.
Trial Registration
ChiCTR-ONC-10000812
doi:10.1186/1471-2369-13-123
PMCID: PMC3506529  PMID: 23013330
Urine; Soluble CD163 (sCD163); Sepsis; Systemic inflammatory response syndrome (SIRS); Prognosis; Acute kidney injury (AKI)
8.  Value of soluble TREM-1, procalcitonin, and C-reactive protein serum levels as biomarkers for detecting bacteremia among sepsis patients with new fever in intensive care units: a prospective cohort study 
BMC Infectious Diseases  2012;12:157.
Background
The purpose of this study was to explore the diagnostic value of soluble triggering receptor expressed on myeloid cells 1 (sTREM-1), procalcitonin (PCT), and C-reactive protein (CRP) serum levels for differentiating sepsis from SIRS, identifying new fever caused by bacteremia, and assessing prognosis when new fever occurred.
Methods
We enrolled 144 intensive care unit (ICU) patients: 60 with systemic inflammatory response syndrome (SIRS) and 84 with sepsis complicated by new fever at more than 48 h after ICU admission. Serum sTREM-1, PCT, and CRP levels were measured on the day of admission and at the occurrence of new fever (>38.3°C) during hospitalization. Based on the blood culture results, the patients were divided into a blood culture-positive bacteremia group (33 patients) and blood culture-negative group (51 patients). Based on 28-day survival, all patients, both blood culture-positive and -negative, were further divided into survivor and nonsurvivor groups.
Results
On ICU day 1, the sepsis group had higher serum sTREM-1, PCT, and CRP levels compared with the SIRS group (P <0.05). The areas under the curve (AUC) for these indicators were 0.868 (95% CI, 0.798–0.938), 0.729 (95% CI, 0.637–0.821), and 0.679 (95% CI, 0.578–0.771), respectively. With 108.9 pg/ml as the cut-off point for serum sTREM-1, sensitivity was 0.83 and specificity was 0.81. There was no statistically significant difference in serum sTREM-1 or PCT levels between the blood culture-positive and -negative bacteremia groups with ICU-acquired new fever. However, the nonsurvivors in the blood culture-positive bacteremia group had higher levels of serum sTREM-1 and PCT (P <0.05), with a prognostic AUC for serum sTREM-1 of 0.868 (95% CI, 0.740–0.997).
Conclusions
Serum sTREM-1, PCT, and CRP levels each have a role in the early diagnosis of sepsis. Serum sTREM-1, with the highest sensitivity and specificity of all indicators studied, is especially notable. sTREM-1, PCT, and CRP levels are of no use in determining new fever caused by bacteremia in ICU patients, but sTREM-1 levels reflect the prognosis of bacteremia.
Trial registration
ClinicalTrial.gov identifier NCT01410578
doi:10.1186/1471-2334-12-157
PMCID: PMC3426475  PMID: 22809118
Soluble triggering receptor expressed on myeloid cells 1 (sTREM-1); Fever; Sepsis; Bacteremia; Diagnosis; Prognosis

Results 1-8 (8)