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author:("Li, fangchi")
1.  Reassortant Eurasian Avian-Like Influenza A(H1N1) Virus from a Severely Ill Child, Hunan Province, China, 2015 
Emerging Infectious Diseases  2016;22(11):1930-1936.
Infectivity and virulence of this virus in mice are higher than for previous human-origin Eurasian avian–like viruses.
In 2015, a novel influenza A(H1N1) virus was isolated from a boy in China who had severe pneumonia. The virus was a genetic reassortant of Eurasian avian-like influenza A(H1N1) (EA-H1N1) virus. The hemagglutinin, neuraminidase, and matrix genes of the reassortant virus were highly similar to genes in EA-H1N1 swine influenza viruses, the polybasic 1 and 2, polymerase acidic, and nucleoprotein genes originated from influenza A(H1N1)pdm09 virus, and the nonstructural protein gene derived from classical swine influenza A(H1N1) (CS H1N1) virus. In a mouse model, the reassortant virus, termed influenza A/Hunan/42443/2015(H1N1) virus, showed higher infectivity and virulence than another human EA-H1N1 isolate, influenza A/Jiangsu/1/2011(H1N1) virus. In the respiratory tract of mice, virus replication by influenza A/Hunan/42443/2015(H1N1) virus was substantially higher than that by influenza A/Jiangsu/1/2011(H1N1) virus. Human-to-human transmission of influenza A/Hunan/42443/2015(H1N1) virus has not been detected; however, given the circulation of novel EA-H1N1 viruses in pigs, enhanced surveillance should be instituted among swine and humans.
PMCID: PMC5088044  PMID: 27767007
viruses; influenza virus; influenza A(H1N1) virus; influenza; reassortant virus; genetic reassortant; Eurasian avian-like virus; EA-H1N1; clinical features; infectivity; virulence; China; novel virus; human origin; swine influenza virus; respiratory infections
2.  The inhibition of EZH2 ameliorates osteoarthritis development through the Wnt/β-catenin pathway 
Scientific Reports  2016;6:29176.
The purpose of our study was to elucidate the role of the histone methyltransferase enhancer of zeste homologue 2 (EZH2) in the pathophysiology of osteoarthritis (OA) and to develop a strategy to modulate EZH2 activity for OA treatment. The expression of EZH2 in normal and OA human cartilage was compared by western blotting. The effect of EZH2 overexpression and inhibition on chondrocyte hypertrophy related gene expression was examined by real-time PCR, and histone methylation on the promoter of the Wnt inhibitor SFRP1 was analyzed using a chromatin immunoprecipitation (ChIP) PCR. Histological assessment of OA mice joint was carried out to assess the in vivo effects of EZH2 inhibitor EPZ005687. We found EZH2 level was significantly increased in the chondrocytes of OA patients compared to normal humans. Overexpression of EZH2 promoted Indian Hedgehog, MMP-13, ADAMTS-5 and COLX expression, while inhibition of EZH2 reversed this trend. Furthermore, the induction of EZH2 led to β-catenin signaling activation by increasing H3K27me3 on the promoter of SFRP1, while the inhibition of EZH2 silenced β-catenin signaling. Finally, intraarticular injection of EPZ005687 delayed OA development in mice. These results implicated EZH2 activity in OA development. Pharmacological inhibition of EZH2 may be an effective therapeutic approach for osteoarthritis.
PMCID: PMC4990905  PMID: 27539752
3.  Overexpression of Sirtuin 6 suppresses cellular senescence and NF-κB mediated inflammatory responses in osteoarthritis development 
Scientific Reports  2015;5:17602.
The aim of our study was to evaluate if Sirt6, a NAD + dependent histone deacetylase, plays a protective role in cartilage degeneration by suppressing cellular senescence and inflammatory responses. The expression level of sirt6 in normal and OA human knee articular cartilage was compared by immunofluorescence and western blotting. The effect of sirt6 overexpression on replicative senescence of chondrocytes and NF-κB target genes expression was evaluated. Histological assessment of OA mice knee joint was carried out to assess the in vivo effects of sirt6 overexpression on mice chondrocytes. We found sirt6 level was significantly decreased in the articular chondrocytes of OA patients compare to normal human. SA-β-gal staining revealed that overexpression of sirt6 suppressed replicative senescence of chondrocytes. Meanwhile, the expression of NF-κB dependent genes were significantly attenuated by sirt6 overxpression. Safranin-O staining and OARSI score of knee joint cartilage in OA mice revealed that Lenti-Sirt6 intraarticular injection could protect mice chondrocytes from degeneration. These data strongly suggest that overexpression of Sirt6 can prevent OA development by reducing both the inflammatory response and chondrocytes senescence. Therefore, the development of specific activators of Sirt6 may have therapeutic potential for the treatment of OA.
PMCID: PMC4671011  PMID: 26639398
4.  Detection and Genetic Characteristics of H9N2 Avian Influenza Viruses from Live Poultry Markets in Hunan Province, China 
PLoS ONE  2015;10(11):e0142584.
H9N2 avian influenza viruses (AIVs) are highly prevalent and of low pathogenicity in domestic poultry. These viruses show a high genetic compatibility with other subtypes of AIVs and have been involved in the genesis of H5N1, H7N9 and H10N8 viruses causing severe infection in humans. The first case of human infection with H9N2 viruses in Hunan province of China have been confirmed in November 2013 and identified that H9N2 viruses from live poultry markets (LPMs) near the patient’s house could be the source of infection. However, the prevalence, distribution and genetic characteristics of H9N2 viruses in LPMs all over the province are not clear. We collected and tested 3943 environmental samples from 380 LPMs covering all 122 counties/districts of Hunan province from February to April, 2014. A total of 618 (15.7%) samples were H9 subtype positive and 200 (52.6%) markets in 98 (80.3%) counties/districts were contaminated with H9 subtype AIVs. We sequenced the entire coding sequences of the genomes of eleven H9N2 isolates from environmental samples. Phylogenetic analysis showed that the gene sequences of the H9N2 AIVs exhibited high homology (94.3%-100%). All eleven viruses were in a same branch in the phylogenetic trees and belonged to a same genotype. No gene reassortment had been found. Molecular analysis demonstrated that all the viruses had typical molecular characteristics of contemporary avian H9N2 influenza viruses. Continued surveillance of AIVs in LPMs is warranted for identification of further viral evolution and novel reassortants with pandemic potential.
PMCID: PMC4640513  PMID: 26554921
5.  Genome-wide association study identifies new susceptibility loci for adolescent idiopathic scoliosis in Chinese girls 
Nature Communications  2015;6:8355.
Adolescent idiopathic scoliosis (AIS) is a structural deformity of the spine affecting millions of children. As a complex disease, the genetic aetiology of AIS remains obscure. Here we report the results of a four-stage genome-wide association study (GWAS) conducted in a sample of 4,317 AIS patients and 6,016 controls. Overall, we identify three new susceptibility loci at 1p36.32 near AJAP1 (rs241215, Pcombined=2.95 × 10−9), 2q36.1 between PAX3 and EPHA4 (rs13398147, Pcombined=7.59 × 10−13) and 18q21.33 near BCL-2 (rs4940576, Pcombined=2.22 × 10−12). In addition, we refine a previously reported region associated with AIS at 10q24.32 (rs678741, Pcombined=9.68 × 10−37), which suggests LBX1AS1, encoding an antisense transcript of LBX1, might be a functional variant of AIS. This is the first GWAS investigating genetic variants associated with AIS in Chinese population, and the findings provide new insight into the multiple aetiological mechanisms of AIS.
The authors perform a genome-wide association study of adolescent idiopathic scoliosis patients of Han Chinese descent, and identify 3 new loci for disease susceptibility.
PMCID: PMC4595747  PMID: 26394188
6.  Cervical Total Disc Replacement is Superior to Anterior Cervical Decompression and Fusion: A Meta-Analysis of Prospective Randomized Controlled Trials 
PLoS ONE  2015;10(3):e0117826.
Despite being considered the standard surgical procedure for symptomatic cervical disc disease, anterior cervical decompression and fusion invariably accelerates adjacent segment degeneration. Cervical total disc replacement is a motion-preserving procedure developed as a substitute to fusion. Whether cervical total disc replacement is superior to fusion remains unclear.
We comprehensively searched PubMed, EMBASE, Medline, and the Cochrane Library in accordance with the inclusion criteria to identify possible studies. The retrieved results were last updated on December 12, 2014. We classified the studies as short-term and midterm follow-up.
Nineteen randomized controlled trials involving 4516 cases were identified. Compared with anterior cervical decompression and fusion, cervical total disc replacement had better functional outcomes (neck disability index [NDI], NDI success, neurological success, neck pain scores reported on a numerical rating scale [NRS], visual analog scales scores and overall success), greater segmental motion at the index level, fewer adverse events and fewer secondary surgical procedures at the index and adjacent levels in short-term follow-up (P < 0.05). With midterm follow-up, the cervical total disc replacement group indicated superiority in the NDI, neurological success, pain assessment (NRS), and secondary surgical procedures at the index level (P < 0.05). The Short Form 36 (SF-36) and segmental motion at the adjacent level in the short-term follow-up showed no significant difference between the two procedures, as did the secondary surgical procedure rates at the adjacent level with midterm follow-up (P > 0.05).
Cervical total disc replacement presented favorable functional outcomes, fewer adverse events, and fewer secondary surgical procedures. The efficacy and safety of cervical total disc replacement are superior to those of fusion. Longer-term, multicenter studies are required for a better evaluation of the long-term efficacy and safety of the two procedures.
PMCID: PMC4379027  PMID: 25822465
7.  Evolutionary analysis of rubella viruses in mainland China during 2010–2012: endemic circulation of genotype 1E and introductions of genotype 2B 
Scientific Reports  2015;5:7999.
Rubella remains a significant burden in mainland China. In this report, 667 viruses collected in 24 of 31 provinces of mainland China during 2010–2012 were sequenced and analyzed, significantly extending previous reports on limited numbers of viruses collected before 2010. Only viruses of genotypes 1E and 2B were found. Genotype 1E viruses were found in all 24 provinces. Genotype 1E viruses were likely introduced into mainland China around 1997 and endemic transmission of primarily one lineage became established. Viruses reported here from 2010–2012 are largely in a single cluster within this lineage. Genotype 2B viruses were rarely detected in China prior to 2010. This report documents a previously undetected 2B lineage, which likely became endemic in eastern provinces of China between 2010 and 2012. Bayesian analyses were performed to estimate the evolutionary rates and dates of appearance of the genotype 1E and 2B viral linages in China. A skyline plot of viral population diversity did not provide evidence of reduction of diversity as a result of vaccination, but should be useful as a baseline for such reductions as vaccination programs for rubella become widespread in mainland China.
PMCID: PMC4303870  PMID: 25613734
8.  Do bisphosphonates affect bone healing? A meta-analysis of randomized controlled trials 
Whether bisphosphonates affect indirect bone healing is still unclear.
We carried out a comprehensive search strategy. Only randomized controlled trials were included. Two reviewers independently assessed methodological qualities and extracted outcome data. Analysis was performed with RevMan 5.2.
Eight eligible randomized controlled trials with 2,508 patients were included. Meta-analysis results showed that no statistically significant differences were founded in indirect bone healing in short time (within 3 months) (relative risk (RR) 1.40, relative the control group; 95% CI 0.36 to 5.49) and in long-term (more than 12 months) postoperation (RR 1.0; 95% CI 0.98 to 1.02) between bisphosphonates infusion groups and control groups. There were no statistically significant differences of indirect bone healing between early and delay bisphosphonates administration groups. Bisphosphonates infusion after lumbar infusion surgery could promote bone healing and shorten fusion time in 6 months postoperation (RR 1.35; 95% CI 1.11 to 1.66).
There was no clinically detectable delay to fracture healing via external callus formation following bisphosphonates treatment. Considering the benefit aspects of bisphosphonates for osteoporosis treatment, we recommend bisphosphonates infusion after fracture fixation surgery and lumbar fusion surgery.
PMCID: PMC4058448  PMID: 24902588
Bisphosphonates; Indirect bone healing; Lumbar fusion; Randomized controlled trials; Meta-analysis
9.  Stromal Cell-derived Factor-1 and its Receptor CXCR4 are Upregulated Expression in Degenerated Intervertebral Discs 
Background: Although chemokine stromal cell-derived factor 1 (SDF-1) and its receptor CXCR4 induce degradation of articular cartilage in rheumatoid arthritis (RA) and osteoarthritis (OA), the association between the SDF-1/CXCR4 pathway and degradation of the cartilaginous endplate and nucleus pulposus has not been thoroughly clarified. We investigated the expression of SDF-1 and CXCR4 in intervertebral discs (IVDs).
Methods: SDF-1 and CXCR4 levels in human IVDs and the rat L5/6 motion segment were quantified by enzyme-linked immunosorbent assay. SDF-1 staining was quantified using a microscope and Image-Pro Plus software. Integrated optical density (IOD) served as the measurement parameter. The number of CXCR4 immunoreactive cells was expressed as a percentage of the total number of cells.
Results: SDF-1 and CXCR4 were both expressed in IVDs, and the levels of SDF-1 and CXCR4 were both significantly higher in the degeneration group than in the normal group of human (or rat) discs. Both nucleus pulposus cells and cartilaginous endplate cells expressed the CXCR4 protein. Furthermore, a positive correlation was observed between the SDF-1 IOD value and the percentage of CXCR4-positive disc cells in the nucleus pulposus and cartilaginous endplate. The SDF-1 IOD values were significantly higher in the outer annular fibrosus and bone/endplate junction region than in the nucleus pulposus and cartilaginous endplate in the rat specimens.
Conclusions: Our findings suggest upregulated expression of SDF-1 and its receptor CXCR4 in degenerated IVD.
PMCID: PMC3917111  PMID: 24516346
SDF-1; CXCR4; intervertebral disc; nucleus pulposus; endplate
10.  Complete Genome Sequence of an H12N8 Avian Influenza Virus Isolated from Wild Bird Feces in Hunan East Dongting Lake National Nature Reserve 
Genome Announcements  2013;1(5):e00891-13.
An H12N8 subtype avian influenza virus (AIV) was isolated from a wild bird in China in 2011. It is the first report of isolation of the H12N8 subtype AIV in Asia. Phylogenetic analysis results suggested it is a reassortant, and all eight gene segments belong to the Eurasian gene pool.
PMCID: PMC3813187  PMID: 24158557
11.  Single Endemic Genotype of Measles Virus Continuously Circulating in China for at Least 16 Years 
PLoS ONE  2012;7(4):e34401.
The incidence of measles in China from 1991 to 2008 was reviewed, and the nucleotide sequences from 1507 measles viruses (MeV) isolated during 1993 to 2008 were phylogenetically analyzed. The results showed that measles epidemics peaked approximately every 3 to 5 years with the range of measles cases detected between 56,850 and 140,048 per year. The Chinese MeV strains represented three genotypes; 1501 H1, 1 H2 and 5 A. Genotype H1 was the predominant genotype throughout China continuously circulating for at least 16 years. Genotype H1 sequences could be divided into two distinct clusters, H1a and H1b. A 4.2% average nucleotide divergence was found between the H1a and H1b clusters, and the nucleotide sequence and predicted amino acid homologies of H1a viruses were 92.3%–100% and 84.7%–100%, H1b were 97.1%–100% and 95.3%–100%, respectively. Viruses from both clusters were distributed throughout China with no apparent geographic restriction and multiple co-circulating lineages were present in many provinces. Cluster H1a and H1b viruses were co-circulating during 1993 to 2005, while no H1b viruses were detected after 2005 and the transmission of that cluster has presumably been interrupted. Analysis of the nucleotide and predicted amino acid changes in the N proteins of H1a and H1b viruses showed no evidence of selective pressure. This study investigated the genotype and cluster distribution of MeV in China over a 16-year period to establish a genetic baseline before MeV elimination in Western Pacific Region (WPR). Continuous and extensive MeV surveillance and the ability to quickly identify imported cases of measles will become more critical as measles elimination goals are achieved in China in the near future. This is the first report that a single endemic genotype of measles virus has been found to be continuously circulating in one country for at least 16 years.
PMCID: PMC3332093  PMID: 22532829
12.  Responses of human adipose-derived mesenchymal stem cells to chemical microenvironment of the intervertebral disc 
Human adipose-derived mesenchymal stem cells (ADMSCs) may be ideal source of cells for intervertebral disc (IVD) regeneration, but the harsh chemical microenvironment of IVD may significantly influence the biological and metabolic vitality of ADMSCs and impair their repair potential. This study aimed to investigate the viability, proliferation and the expression of main matrix proteins of ADMSCs in the chemical microenvironment of IVD under normal and degeneration conditions.
ADMSCs were harvested from young (aged 8-12 years, n = 6) and mature (aged 33-42 years, n = 6) male donors and cultured under standard condition and IVD-like conditions (low glucose, acidity, high osmolarity, and combined conditions) for 2 weeks. Cell viability was measured by annexin V-FITC and PI staining and cell proliferation was measured by MTT assay. The expression of aggrecan and collagen-I was detected by real-time quantitative polymerase chain reaction and Western blot analysis.
IVD-like glucose condition slightly inhibited cell viability, but increased the expression of aggrecan. In contrast, IVD-like osmolarity, acidity and the combined conditions inhibited cell viability and proliferation and the expression of aggrecan and collagen-I. ADMSCs from young and mature donors exhibited similar responses to the chemical microenvironments of IVD.
IVD-like low glucose is a positive factor but IVD-like high osmolarity and low pH are deleterious factors that affect the survival and biological behaviors of ADMSCs. These findings may promote the translational research of ADMSCs in IVD regeneration for the treatment of low back pain.
PMCID: PMC3338074  PMID: 22424131
Adipose-derived mesenchymal stem cells; Intervertebral disc; Chemical microenvironment

Results 1-12 (12)